Publications

Stanford University Professor in Pulmonary and Critical Care Medicine

Publications

  • The Hallmarks of Severe Pulmonary Arterial Hypertension: The Cancer Hypothesis - Ten years later. American journal of physiology. Lung cellular and molecular physiology Cool, C. D., Kuebler, W. M., Bogaard, H. J., Spiekerkoetter, E., Nicolls, M. R., Voelkel, N. F. 2020

    Abstract

    Severe forms of pulmonary arterial hypertension (PAH) are most frequently the consequence of a lumen-obliterating angiopathy. One pathobiological model is, that the initial pulmonary vascular endothelial cell injury and apoptosis is followed by the evolution of phenotypically altered, apoptosis-resistant, proliferating cells and an inflammatory vascular immune response. Although there may be a vasoconstrictive disease component, the increased pulmonary vascular shear stress in established PAH is caused largely by the vascular wall pathology. In this review, we revisit the "quasi-malignancy concept" of severe PAH and examine to what extent the hallmarks of PAH can be compared to the hallmarks of cancer. The cancer model of severe PAH, based on the growth of abnormal vascular and bone marrow-derived cells, may enable the emergence of novel cell-based PAH treatment strategies.

    View details for DOI 10.1152/ajplung.00476.2019

    View details for PubMedID 32023082

  • Machine learning algorithms to differentiate among pulmonary complications after hematopoietic cell transplant. Chest Sharifi, H., Lai, Y. K., Guo, H., Hoppenfeld, M., Guenther, Z. D., Johnston, L., Brondstetter, T., Chhatwani, L., Nicolls, M. R., Hsu, J. L. 2020

    Abstract

    Pulmonary complications, including infections, are highly prevalent in patients after hematopoietic cell transplant with chronic graft-versus-host disease. These comorbid diseases can make the diagnosis of early lung graft-versus-host disease (bronchiolitis obliterans syndrome) challenging. A quantitative method to differentiate among these pulmonary diseases can address diagnostic challenges and facilitate earlier and more targeted therapy.We conducted a single center study of 66 patients with computed tomography chest scans analyzed with a quantitative imaging tool known as parametric response mapping. Parametric response mapping results were correlated with pulmonary function tests and clinical characteristics. Five parametric response mapping metrics were applied to K-means clustering and support vector machine models to distinguish among post-transplant lung complications solely from quantitative output.Compared to parametric response mapping, spirometry showed a moderate correlation with radiographic air trapping, and total lung capacity and residual volume showed a strong correlation with radiographic lung volumes. K-means clustering analysis distinguished 4 unique clusters. Clusters 2 and 3 represented obstructive physiology (encompassing 81% of patients with bronchiolitis obliterans syndrome) in increasing severity (percent air trapping 15.6% and 43.0%, respectively). Cluster 1 was dominated by normal lung, and cluster 4 was characterized by patients with parenchymal opacities. A support vector machine algorithm differentiated bronchiolitis obliterans syndrome with specificity of 88%, sensitivity of 83%, accuracy of 86% and an area under the receiver operating characteristic curve of 0.85.Our machine learning models offer a quantitative approach for the identification of bronchiolitis obliterans syndrome versus other lung diseases, including late pulmonary complications after hematopoietic cell transplant.

    View details for DOI 10.1016/j.chest.2020.02.076

    View details for PubMedID 32343962

  • Mural Cell SDF1 Signaling is Associated with the Pathogenesis of Pulmonary Arterial Hypertension. American journal of respiratory cell and molecular biology Yuan, K., Liu, Y., Zhang, Y., Nathan, A., Tian, W., Yu, J., Sweatt, A. J., Condon, D., Chakraborty, A., Agarwal, S., Auer, N., Zhang, S., Wu, J. C., Zamanian, R. T., Nicolls, M. R., de Jesus Perez, V. A. 2020

    Abstract

    Pulmonary artery smooth muscle cells (PASMCs) and pericytes are NG2+ mural cells that provide structural support to pulmonary arteries and capillaries. In pulmonary arterial hypertension (PAH), both mural cell types contribute to PA muscularization but whether similar mechanisms are responsible for their behavior is unknown.RNA-Seq was used to compare the gene profile of pericytes and PASMCs from PAH and healthy lungs. NG2-Cre-ER mice were used to generate NG2-selective reporter mice (NG2tdT) for cell lineage identification and tamoxifen-inducible mice for NG2-selective SDF1 knockout (SDF1NG2-KO).Hierarchical clustering of RNA-seq data demonstrated that the genetic profile of PAH pericytes and PASMCs is highly similar. Cellular lineage staining studies on NG2tdT mice in chronic hypoxia showed that similar to PAH, tdT+ cells accumulate in muscularized microvessels and demonstrate significant upregulation of SDF1, a chemokine involved in chemotaxis and angiogenesis. Compared to controls, SDF1NG2-KO mice in chronic hypoxia had reduced muscularization and lower abundance of NG2+ cells around microvessels. SDF1 stimulation in healthy pericytes induced greater contractility and impaired their capacity to establish endothelial-pericyte communications. In contrast, SDF1 knockdown reduced PAH pericyte contractility and improved their capacity to associate with vascular tubes in co-culture.SDF1 is upregulated in NG2+ mural cells and is associated with PA muscularization. Targeting SDF1 could help prevent and/or reverse muscularization in PAH.

    View details for DOI 10.1165/rcmb.2019-0401OC

    View details for PubMedID 32084325

  • Safety and Efficacy of B-cell Depletion with Rituximab for the Treatment of Systemic Sclerosis-associated Pulmonary Arterial Hypertension in a Multi-center NIH Clinical Trial Nicolls, M., Badesch, D., Chung, L., Domsic, R., Medsger, T., Pinckney, A., Keyes-Elstein, L., D'Aveta, C., Spychala, M., White, R., Hassoun, P., Torres, F., Molitor, J., Khanna, D., Maeker, H., Welch, B., Goldmuntz, E., Zamanian, R., ASC01 Investigators WILEY. 2019
  • Late Breaking Abstract - Safety and efficacy of B-cell depletion with rituximab for the treatment of systemic sclerosis-associated pulmonary arterial hypertension Zamanian, R., Badesch, D., Chung, L., Domsic, R., Medsger, T., Pinckney, A., Keyes-Elstein, L., D'Aveta, C., Spychala, M., White, J., Hassoun, P., Torres, F., Molitor, J., Khanna, D., Maeker, H., Welch, B., Goldmuntz, E., Nicolls, M., Asco1 Investigators EUROPEAN RESPIRATORY SOC JOURNALS LTD. 2019
  • Preservation of Microvascular Integrity in Murine Orthotopic Tracheal Allografts by Clopidogrel TRANSPLANTATION Heim, C., Khan, M., von Silva-Tarouca, B., Kuckhahn, A., Stamminger, T., Ramsperger-Gleixner, M., Nicolls, M. R., Weyand, M., Ensminger, S. M. 2019; 103 (5): 899–908
  • Inducible expression of immediate early genes is regulated through dynamic chromatin association by NF45/ILF2 and NF90/NF110/ILF3 PLOS ONE Wu, T., Shi, L., Lowe, A. W., Nicolls, M. R., Kao, P. N. 2019; 14 (4)
  • Loss of Endothelium-Derived Wnt5a Is Associated With Reduced Pericyte Recruitment and Small Vessel Loss in Pulmonary Arterial Hypertension CIRCULATION Yuan, K., Shamskhou, E. A., Orcholski, M. E., Nathan, A., Reddy, S., Honda, H., Mani, V., Zeng, Y., Ozen, M. O., Wang, L., Demirci, U., Tian, W., Nicolls, M. R., Perez, V. 2019; 139 (14): 1710–24
  • Discovery of Distinct Immune Phenotypes Using Machine Learning in Pulmonary Arterial Hypertension CIRCULATION RESEARCH Sweatt, A. J., Hedlin, H. K., Balasubramanian, V., Hsi, A., Blum, L. K., Robinson, W. H., Haddad, F., Hickey, P. M., Condliffe, R., Lawrie, A., Nicolls, M. R., Rabinovitch, M., Khatri, P., Zamanian, R. T. 2019; 124 (6): 904–19
  • Preservation of microvascular integrity in murine orthotopic tracheal allografts by clopidogrel. Transplantation Heim, C., Khan, M. A., Silva-Tarouca, B. v., Kuckhahn, A., Stamminger, T., Ramsperger-Gleixner, M., Nicolls, M. R., Weyand, M., Ensminger, S. M. 2019

    Abstract

    BACKGROUND: Survival after lung transplantation is mainly limited by the development of chronic lung allograft dysfunction (CLAD). The aim of this study was to investigate if platelet inhibition by clopidogrel has a functionally relevant influence on the microvascular integrity of orthotopic tracheal allografts as an anatomic basis for the development of CLAD.METHODS: We orthotopically transplanted C57Bl/6 (H-2) tracheas into CBA.J (H-2) recipients which afterwards received clopidogrel (1mg/kg). Morphometric analysis was performed by measuring epithelial height in proportion to thickness of the lamina propria (ELR). Tissue oxygenation was determined using a fluorescence quenching technique and graft perfusion monitoring was performed by Laser Doppler Flowmetry and lectin-binding assay. Immunohistochemistry was used for detection of CD31 and iNOS while iron deposition was shown with Prussian blue reaction. Quantitative RT-PCR analysis was used for gene expression analysis.RESULTS: Isografts maintained good oxygenation and perfusion throughout the experiment, while both were drastically reduced in allografts. Treatment with clopidogrel attenuated graft hypoxia and reduced loss of perfusion. Additionally, clopidogrel led to increased ELR while iron deposition was impaired. Gene expression analysis revealed elevated levels of angiogenic VEGF in the clopidogrel group. Improved endothelial function shown by immunohistochemistry (CD31, iNOS).CONCLUSIONS: Continuous administration of clopidogrel significantly improved tissue oxygenation, limited microvascular leakiness, and prevented airway ischemia. These data demonstrate that clopidogrel ameliorates microvascular injury during acute airway rejection which is a known predisposing factor for the development of CLAD.

    View details for PubMedID 30801550

  • Anti-hyperlipidaemic effects of synthetic analogues of nordihydroguaiaretic acid in dyslipidaemic rats BRITISH JOURNAL OF PHARMACOLOGY Singh, M., Bittner, S., Li, Y., Bittner, A., Han, L., Cortez, Y., Inayathullah, M., Arif, Z., Parthasarathi, R., Rajadas, J., Shen, W., Nicolls, M. R., Kraemer, F. B., Azhar, S. 2019; 176 (3): 369–85

    View details for DOI 10.1111/bph.14528

    View details for Web of Science ID 000455517100003

  • Airway hypoxia in lung transplantation CURRENT OPINION IN PHYSIOLOGY Pasupneti, S., Nicolls, M. R. 2019; 7: 21–26
  • The Lymphatic System in Obesity, Insulin Resistance, and Cardiovascular Diseases. Frontiers in physiology Jiang, X., Tian, W., Nicolls, M. R., Rockson, S. G. 2019; 10: 1402

    Abstract

    Obesity, insulin resistance, dyslipidemia, and hypertension are fundamental clinical manifestations of the metabolic syndrome. Studies over the last few decades have implicated chronic inflammation and microvascular remodeling in the development of obesity and insulin resistance. Newer observations, however, suggest that dysregulation of the lymphatic system underlies the development of the metabolic syndrome. This review summarizes recent advances in the field, discussing how lymphatic abnormality promotes obesity and insulin resistance, and, conversely, how the metabolic syndrome impairs lymphatic function. We also discuss lymphatic biology in metabolically dysregulated diseases, including type 2 diabetes, atherosclerosis, and myocardial infarction.

    View details for DOI 10.3389/fphys.2019.01402

    View details for PubMedID 31798464

    View details for PubMedCentralID PMC6868002

  • Phenotypically-Silent Bone Morphogenetic Protein Receptor 2 (Bmpr2) Mutations Predispose Rats to Inflammation-Induced Pulmonary Arterial Hypertension by Enhancing The Risk for Neointimal Transformation. Circulation Tian, W., Jiang, X., Sung, Y. K., Shuffle, E., Wu, T. H., Kao, P. N., Tu, A. B., Dorfmüller, P., Cao, A., Wang, L., Peng, G., Kim, Y., Zhang, P., Chappell, J., Pasupneti, S., Dahms, P., Maguire, P., Chaib, H., Zamanian, R., Peters-Golden, M., Snyder, M. P., Voelkel, N. F., Humbert, M., Rabinovitch, M., Nicolls, M. R. 2019

    Abstract

    Bmpr2 mutations are critical risk factors for hereditary pulmonary arterial hypertension (hPAH) with approximately 20% of carriers developing disease. There is an unmet medical need to understand how environmental factors, such as inflammation, render Bmpr2 mutants susceptible to PAH. Overexpressing 5-lipoxygenase (5-LO) provokes lung inflammation and transient PAH in Bmpr2+/- mice. Accordingly, 5-LO and its metabolite, leukotriene B4 (LTB4), are candidates for the 'second hit'. The purpose of this study was to determine how 5-LO-mediated pulmonary inflammation synergized with phenotypically-silent Bmpr2 defects to elicit significant pulmonary vascular disease in rats.Monoallelic Bmpr2 mutant rats were generated and found phenotypically normal for up to one year of observation. To evaluate whether a second hit would elicit disease, animals were exposed to 5-LO-expressing adenovirus (AdAlox5), monocrotaline, SU5416, SU5416 with chronic hypoxia or chronic hypoxia alone. Bmpr2-mutant hPAH patient samples were assessed for neointimal 5-LO expression. Pulmonary artery endothelial cells (PAECs) with impaired BMPR2 signaling were exposed to increased 5-LO-mediated inflammation and were assessed for phenotypic and transcriptomic changes.Lung inflammation, induced by intratracheal delivery of AdAlox5, elicited severe PAH with intimal remodeling in Bmpr2+/- rats but not in their wild-type littermates. Neointimal lesions in the diseased Bmpr2+/- rats gained endogenous 5-LO expression associated with elevated LTB4 biosynthesis. Bmpr2-mutant hPAH patients similarly expressed 5-LO in the neointimal cells. In vitro, BMPR2 deficiency, compounded by 5-LO-mediated inflammation, generated apoptosis-resistant, and proliferative PAECs with mesenchymal characteristics. These transformed cells expressed nuclear envelope-localized 5-LO consistent with induced LTB4 production, as well as a transcriptomic signature similar to clinical disease, including upregulated NF-κB, IL-6, and TGF-β signaling pathways. The reversal of PAH and vasculopathy in Bmpr2 mutants by TGF-β antagonism suggests that TGF-β is critical for neointimal transformation.In a new 'two-hit' model of disease, lung inflammation induced severe PAH pathology in Bmpr2+/- rats. Endothelial transformation required the activation of canonical and noncanonical TGF-β signaling pathways and was characterized by 5-LO nuclear envelope translocation with enhanced LTB4 production. This study offers one explanation of how an environmental injury unleashes the destructive potential of an otherwise-silent genetic mutation.

    View details for DOI 10.1161/CIRCULATIONAHA.119.040629

    View details for PubMedID 31462075

  • Inducible expression of immediate early genes is regulated through dynamic chromatin association by NF45/ILF2 and NF90/NF110/ILF3. PloS one Wu, T. H., Shi, L., Lowe, A. W., Nicolls, M. R., Kao, P. N. 2019; 14 (4): e0216042

    Abstract

    Immediate early gene (IEG) transcription is rapidly activated by diverse stimuli. This transcriptional regulation is assumed to involve constitutively expressed nuclear factors that are targets of signaling cascades initiated at the cell membrane. NF45 (encoded by ILF2) and its heterodimeric partner NF90/NF110 (encoded by ILF3) are chromatin-interacting proteins that are constitutively expressed and localized predominantly in the nucleus. Previously, NF90/NF110 chromatin immunoprecipitation followed by deep sequencing (ChIP-seq) in K562 erythroleukemia cells revealed its enriched association with chromatin at active promoters and strong enhancers. NF90/NF110 specifically occupied the promoters of IEGs. Here, ChIP in serum-starved HEK293 cells demonstrated that NF45 and NF90/NF110 pre-exist and specifically occupy the promoters of IEG transcription factors EGR1, FOS and JUN. Cellular stimulation with phorbol myristyl acetate increased NF90/NF110 chromatin association, while decreasing NF45 chromatin association at promoters of EGR1, FOS and JUN. In HEK293 cells stably transfected with doxycycline-inducible shRNA vectors targeting NF90/NF110 or NF45, doxycycline-mediated knockdown of NF90/NF110 or NF45 attenuated the inducible expression of EGR1, FOS, and JUN at the levels of transcription, RNA and protein. Dynamic chromatin association of NF45 and NF90/NF110 at IEG promoters are observed upon stimulation, and NF45 and NF90/NF110 contribute to inducible transcription of IEGs. NF45 and NF90/NF110 operate as chromatin regulators of the immediate early response.

    View details for PubMedID 31022259

  • Discovery of Distinct Immune Phenotypes Using Machine Learning in Pulmonary Arterial Hypertension. Circulation research Sweatt, A. J., Hedlin, H. K., Balasubramanian, V., Hsi, A., Blum, L. K., Robinson, W. H., Haddad, F., Hickey, P. M., Condliffe, R. A., Lawrie, A., Nicolls, M. R., Rabinovitch, M., Khatri, P., Zamanian, R. T. 2019

    Abstract

    Accumulating evidence implicates inflammation in pulmonary arterial hypertension (PAH) and therapies targeting immunity are under investigation, though it remains unknown if distinct immune phenotypes exist.Identify PAH immune phenotypes based on unsupervised analysis of blood proteomic profiles.In a prospective observational study of Group 1 PAH patients evaluated at Stanford University (discovery cohort, n=281) and University of Sheffield (validation cohort, n=104) between 2008-2014, we measured a circulating proteomic panel of 48 cytokines, chemokines, and factors using multiplex immunoassay. Unsupervised machine learning (consensus clustering) was applied in both cohorts independently to classify patients into proteomic immune clusters, without guidance from clinical features. To identify central proteins in each cluster, we performed partial correlation network analysis. Clinical characteristics and outcomes were subsequently compared across clusters. Four PAH clusters with distinct proteomic immune profiles were identified in the discovery cohort. Cluster 2 (n=109) had low cytokine levels similar to controls. Other clusters had unique sets of upregulated proteins central to immune networks- cluster 1 (n=58)(TRAIL, CCL5, CCL7, CCL4, MIF), cluster 3 (n=77)(IL-12, IL-17, IL-10, IL-7, VEGF), and cluster 4 (n=37)(IL-8, IL-4, PDGF-β, IL-6, CCL11). Demographics, PAH etiologies, comorbidities, and medications were similar across clusters. Non-invasive and hemodynamic surrogates of clinical risk identified cluster 1 as high-risk and cluster 3 as low-risk groups. Five-year transplant-free survival rates were unfavorable for cluster 1 (47.6%, CI 35.4-64.1%) and favorable for cluster 3 (82.4%, CI 72.0-94.3%)(across-cluster p<0.001). Findings were replicated in the validation cohort, where machine learning classified four immune clusters with comparable proteomic, clinical, and prognostic features.Blood cytokine profiles distinguish PAH immune phenotypes with differing clinical risk that are independent of World Health Organization Group 1 subtypes. These phenotypes could inform mechanistic studies of disease pathobiology and provide a framework to examine patient responses to emerging therapies targeting immunity.

    View details for PubMedID 30661465

  • High Dose Ubenimex Interferes with the Efficacy of Sildenafil in Experimental Pulmonary Hypertension Dahms, P., Tian, A., Zhang, P., Tu, A. B., Jiang, X., Pasupneti, S., Peng, G., Nicolls, M. R. AMER THORACIC SOC. 2019
  • The Role of Iron-Induced Macrophage Dysregulation in Aspergillus Fumigatus Invasion in Airway Transplantation Matthaiou, E., Manouvakhova, O. M., Sinha, M., Tu, A. B., Clemons, K. V., Stevens, D. A., Nicolls, M. R., Hsu, J. L. AMER THORACIC SOC. 2019
  • HIF1 alpha-Mediated Lymphangiogenesis Influences Airway Transplant Rejection Tu, A. B., Jiang, X., Tian, A., Dahms, P., Zhang, P., Pasupneti, S., Nicolls, M. R. AMER THORACIC SOC. 2019
  • Endothelial HIF-2alpha is Required for the Maintenance of Airway Microvasculature. Circulation Jiang, X., Tian, W., Tu, A. B., Pasupneti, S., Shuffle, E., Dahms, P., Zhang, P., Cai, H., Dinh, T. T., Liu, B., Cain, C., Giaccia, A. J., Butcher, E. C., Simon, C., Semenza, G. L., Nicolls, M. R. 2018

    Abstract

    BACKGROUND: Hypoxia-inducible factors (HIFs), especially HIF-1alpha and HIF-2alpha, are key mediators of the adaptive response to hypoxic stress and play essential roles in maintaining lung homeostasis. Human and animal genetics studies confirm that abnormal HIF correlates with pulmonary vascular pathology and chronic lung diseases, but it remains unclear whether endothelial cell (EC) HIF production is essential for microvascular health. The large airway has an ideal circulatory bed for evaluating histologic changes and physiology in genetically-modified rodents.METHODS: The tracheal microvasculature of mice, with conditionally-deleted or overexpressed HIF-1alpha or HIF-2alpha, was evaluated for anatomy, perfusion, and permeability. Angiogenic signaling studies assessed vascular changes attributable to dysregulated HIF expression. An orthotopic tracheal transplantation model further evaluated the contribution of individual HIF isoforms in airway ECs.RESULTS: The genetic deletion of Hif-2alpha, but not Hif-1alpha, caused tracheal EC apoptosis, diminished pericyte coverage, reduced vascular perfusion, defective barrier function, overlying epithelial abnormalities and subepithelial fibrotic remodeling. HIF-2alpha promoted microvascular integrity in airways through endothelial angiopoietin-1/TIE2 signaling and Notch activity. In functional tracheal transplants, HIF-2alpha deficiency in airway donors accelerated graft microvascular loss, whereas HIF-2alpha or angiopoietin-1 overexpression prolonged transplant microvascular perfusion. Augmented endothelial HIF-2alpha in transplant donors promoted airway microvascular integrity and diminished alloimmune inflammation.CONCLUSIONS: Our findings reveal that the constitutive expression of endothelial HIF-2alpha is required for airway microvascular health.

    View details for PubMedID 30586708

  • Circulating plasmablasts are elevated and produce pathogenic anti-endothelial cell autoantibodies in idiopathic pulmonary arterial hypertension. European journal of immunology Blum, L. K., Cao, R. R., Sweatt, A. J., Bill, M., Lahey, L. J., Hsi, A. C., Lee, C. S., Kongpachith, S., Ju, C. H., Mao, R., Wong, H. H., Nicolls, M. R., Zamanian, R. T., Robinson, W. H. 2018

    Abstract

    Idiopathic pulmonary arterial hypertension (IPAH) is a devastating pulmonary vascular disease in which autoimmune and inflammatory phenomena are implicated. B cells and autoantibodies have been associated with IPAH and identified as potential therapeutic targets. However, the specific populations of B cells involved and their roles in disease pathogenesis are not clearly defined. We aimed to assess the levels of activated B cells (plasmablasts) in IPAH, and to characterize recombinant antibodies derived from these plasmablasts. Blood plasmablasts are elevated in IPAH, remain elevated over time, and produce IgA autoantibodies. Single-cell sequencing of plasmablasts in IPAH revealed repertoires of affinity-matured antibodies with small clonal expansions, consistent with an ongoing autoimmune response. Recombinant antibodies representative of these clonal lineages bound known autoantigen targets and displayed an unexpectedly high degree of polyreactivity. Representative IPAH plasmablast recombinant antibodies stimulated human umbilical vein endothelial cells to produce cytokines and overexpress the adhesion molecule ICAM-1. Together, our results demonstrate an ongoing adaptive autoimmune response involving IgA plasmablasts that produce anti-endothelial cell autoantibodies in IPAH. These antibodies stimulate endothelial cell production of cytokines and adhesion molecules, which may contribute to disease pathogenesis. These findings suggest a role for mucosally-driven autoimmunity and autoimmune injury in the pathogenesis of IPAH. This article is protected by copyright. All rights reserved.

    View details for PubMedID 29369345

  • Loss of Endothelial Derived WNT5A is Associated with Reduced Pericyte Recruitment and Small Vessel Loss in Pulmonary Arterial Hypertension. Circulation Yuan, K., Shamskhou, E. A., Orcholski, M. E., Nathan, A., Reddy, S., Honda, H., Mani, V., Zeng, Y., Ozen, M. O., Wang, L., Demirci, U., Tian, W., Nicolls, M. R., de Jesus Perez, V. A. 2018

    Abstract

    Pulmonary arterial hypertension (PAH) is a life-threatening disorder of the pulmonary circulation associated with loss and impaired regeneration of microvessels. Reduced pericyte coverage of pulmonary microvessels is a pathological feature of PAH and is partly due to the inability of pericytes to respond to signaling cues from neighboring pulmonary microvascular endothelial cells (PMVECs). We have shown that activation of the Wnt/PCP pathway is required for pericyte recruitment but whether production and release of specific Wnt ligands by PMVECs is responsible for Wnt/PCP activation in pericytes is unknown.Isolation of pericytes and PMVECs from healthy donor and PAH lungs was carried out using 3G5 or CD31 antibody conjugated magnetic beads. Wnt expression profile of PMVECs was documented via qPCR using a Wnt primer library. Exosome purification from PMVEC media was carried out using the ExoTIC device. Hemodynamic profile, right ventricular function and pulmonary vascular morphometry were obtained in a conditional endothelial specific Wnt5a knockout ( Wnt5aECKO) mouse model under normoxia, chronic hypoxia and hypoxia recovery.Quantification of Wnt ligand expression in healthy PMVECs co-cultured with pericytes demonstrated a 35-fold increase in Wnt5a, a known Wnt/PCP ligand. This Wnt5a spike was not seen in PAH PMVECs, which correlated with inability to recruit pericytes in matrigel co-culture assays. Exosomes purified from media demonstrated an increase in Wnt5a content when healthy PMVECs were co-cultured with pericytes, a finding that was not observed in exosomes of PAH PMVECs. Furthermore, the addition of either recombinant Wnt5a or purified healthy PMVEC exosomes increased pericyte recruitment to PAH PMVECs in co-culture studies. While no differences were noted in normoxia and chronic hypoxia, Wnt5aECKO mice demonstrated persistent pulmonary hypertension and right ventricular failure four weeks after recovery from chronic hypoxia, which correlated with significant reduction, muscularization and decreased pericyte coverage of microvessels.We identify Wnt5a as a key mediator for the establishment of pulmonary endothelial-pericyte interactions and its loss could contribute to PAH by reducing the viability of newly formed vessels. We speculate that therapies that mimic or restore Wnt5a production could help prevent loss of small vessels in PAH.

    View details for PubMedID 30586764

  • Pilot studies demonstrate the potential benefits of antiinflammatory therapy in human lymphedema. JCI insight Rockson, S. G., Tian, W., Jiang, X., Kuznetsova, T., Haddad, F., Zampell, J., Mehrara, B., Sampson, J. P., Roche, L., Kim, J., Nicolls, M. R. 2018; 3 (20)

    Abstract

    Lymphedema is a common condition affecting millions around the world that still lacks approved medical therapy. Because ketoprofen, an NSAID, has been therapeutic in experimental lymphedema, we evaluated its efficacy in humans.We first performed an exploratory open-label trial. Patients with either primary or secondary lymphedema received ketoprofen 75 mg by mouth 3 times daily for 4 months. Subjects were evaluated for changes in histopathology, with skin thickness, limb volume, and tissue bioimpedance changes serving as secondary endpoints. Based on our encouraging findings, we next conducted a placebo-controlled trial, with the primary outcome defined as a change in skin thickness, as measured by skin calipers. Secondary endpoints for this second study included histopathology, limb volume, bioimpedance, and systemic inflammatory mediators.We enrolled 21 lymphedema patients in the open-label trial, from November 2010 to July 2011. Histopathology and skin thickness were significantly improved at 4 months compared with baseline. In the follow-up, double-blind, placebo-controlled trial, we enrolled 34 patients from August 2011 to October 2015, with 16 ketoprofen recipients and 18 placebo-treated subjects. No serious adverse events occurred. The ketoprofen recipients demonstrated reduced skin thickness, as well as improved composite measures of histopathology and decreased plasma granulocyte CSF (G-CSF) expression.These 2 exploratory studies together support the utility of targeted antiinflammatory therapy with ketoprofen in patients with lymphedema. Our results highlight the promise of such approaches to help restore a failing lymphatic circulation.ClinicalTrials.gov NCT02257970.

    View details for PubMedID 30333315

  • Increased Lymphangiogenesis in Animal Models of Pulmonary Arterial Hypertension Zhang, P., Tian, A. W., Tu, A. B., Jiang, X., Nicolls, M. R. AMER THORACIC SOC. 2018
  • Endothelial HIF-2 alpha Maintains Airway Microvasculature Through Angiopoietin-1/TIE2 Signaling Tu, A., Jiang, X., Tian, W., Nicolls, M. R. AMER THORACIC SOC. 2018
  • The Role of Hypoxia Inducible Factors in Maintenance of Airway Epithelial Health Pasupneti, S., Tian, A., Jiang, X., Nicolls, M. R. AMER THORACIC SOC. 2018
  • Pathology and pathobiology of pulmonary hypertension: state of the art and research perspectives. The European respiratory journal Humbert, M., Guignabert, C., Bonnet, S., Dorfmüller, P., Klinger, J. R., Nicolls, M. R., Olschewski, A. J., Pullamsetti, S. S., Schermuly, R. T., Stenmark, K. R., Rabinovitch, M. 2018

    Abstract

    Clinical and translational research has played a major role in advancing our understanding of pulmonary hypertension (PH), including pulmonary arterial hypertension and other forms of PH with severe vascular remodelling (e.g. chronic thromboembolic PH and pulmonary veno-occlusive disease). However, PH remains an incurable condition with a high mortality rate, underscoring the need for a better transfer of novel scientific knowledge into healthcare interventions. Herein, we review recent findings in pathology (with the questioning of the strict morphological categorisation of various forms of PH into pre- or post-capillary involvement of pulmonary vessels) and cellular mechanisms contributing to the onset and progression of pulmonary vascular remodelling associated with various forms of PH. We also discuss ways to improve management and to support and optimise drug development in this research field.

    View details for PubMedID 30545970

  • A Pro - Con debate: Current Controversies in PAH Pathogenesis at the American Thoracic Society International Meeting in 2017. American journal of physiology. Lung cellular and molecular physiology Kuebler, W. M., Nicolls, M. R., Olschewski, A., Abe, K., Rabinovitch, M., Stewart, D. J., Chan, S. Y., Morrell, N. W., Archer, S. L., Spiekerkoetter, E. 2018

    Abstract

    The following review summarizes the pro-con debate about current controversies regarding the pathogenesis of pulmonary arterial hypertension (PAH) that took place at the American Thoracic Society Conference in May 2017. Leaders in the field of PAH research discussed the importance of the immune system, the role of hemodynamic stress and endothelial apoptosis as well as bone morphogenetic protein receptor 2 (BMPR2) signaling in PAH pathogenesis. While this summary does not intend to resolve obvious conflicts in opinion, we hope that the presented arguments entice further discussions and draw a new generation of enthusiastic researchers into this vibrant field of science to bridge existing gaps for a better understanding and therapy of this fatal disease.

    View details for PubMedID 29877097

  • Microhemorrhage-associated tissue iron enhances the risk forAspergillus fumigatusinvasion in a mouse model of airway transplantation. Science translational medicine Hsu, J. L., Manouvakhova, O. V., Clemons, K. V., Inayathullah, M., Tu, A. B., Sobel, R. A., Tian, A., Nazik, H., Pothineni, V. R., Pasupneti, S., Jiang, X., Dhillon, G. S., Bedi, H., Rajadas, J., Haas, H., Aurelian, L., Stevens, D. A., Nicolls, M. R. 2018; 10 (429)

    Abstract

    Invasive pulmonary disease due to the moldAspergillus fumigatuscan be life-threatening in lung transplant recipients, but the risk factors remain poorly understood. To study this process, we used a tracheal allograft mouse model that recapitulates large airway changes observed in patients undergoing lung transplantation. We report that microhemorrhage-related iron content may be a major determinant ofA. fumigatusinvasion and, consequently, its virulence. Invasive growth was increased during progressive alloimmune-mediated graft rejection associated with high concentrations of ferric iron in the graft. The role of iron inA. fumigatusinvasive growth was further confirmed by showing that this invasive phenotype was increased in tracheal transplants from donor mice lacking the hemochromatosis gene (Hfe -/- ). The invasive phenotype was also increased in mouse syngrafts treated with topical iron solution and in allograft recipients receiving deferoxamine, a chelator that increases iron bioavailability to the mold. The invasive growth of the iron-intolerantA. fumigatusdouble-knockout mutant (ΔsreA/ΔcccA) was lower than that of the wild-type mold. Alloimmune-mediated microvascular damage and iron overload did not appear to impair the host's immune response. In human lung transplant recipients, positive staining for iron in lung transplant tissue was more commonly seen in endobronchial biopsy sections from transplanted airways than in biopsies from the patients' own airways. Collectively, these data identify iron as a major determinant ofA. fumigatusinvasive growth and a potential target to treat or preventA. fumigatusinfections in lung transplant patients.

    View details for PubMedID 29467298

  • Nordihydroguaiaretic acid, a lignan from Larrea tridentata (Creosote bush) protects against ALIOS diet-induced metabolic dysfunction in mice. The Journal of pharmacology and experimental therapeutics Chan, J. K., Bittner, S., Bittner, A., Atwal, S., Shen, W. J., Inayathullah, M., Rajada, J., Nicolls, M. R., Kraemer, F. B., Azhar, S. 2018

    Abstract

    To determine the effects of NDGA on metabolic and molecular changes in response to feeding mice typical American fast food or Western diet, mice were fed with ALIOS diet and subjected to metabolic analysis. Male C57BL/6J mice were randomly assigned to: ALIOS, ALIOS + NDGA, or control diet and maintained on the specific diet for 8 weeks. Mice fed ALIOS diet, showed increased body, liver and epididymal fat pad weight, plasma ALT and AST levels (a measure of liver injury), and liver triglyceride (TG) content. Co-administration of NDGA normalized body and epididymal fat pad weight, ALT and AST levels, and liver TG. NDGA treatment also improved insulin sensitivity but not glucose intolerance in ALIOS diet fed mice. In ALIOS diet fed mice, NDGA supplementation induced PPARα (the master regulator of fatty acid oxidation) and mRNA levels of Cpt1c and Cpt2, key genes involved in fatty acid oxidation as compared to ALIOS diet. NDGA significantly reduced liver ER stress response CHOP protein, as compared to chow or ALIOS diet and also ameliorated ALIOS diet-induced elevation of apoptosis signaling protein, CASP3. Likewise, NDGA downregulated the ALIOS-diet induced mRNA levels of Pparg, Fasn, and Dgat2. NDGA treatment of ALIOS fed mice upregulated the hepatic expression of antioxidant enzymes, GPX4 and PRDX3 proteins. In conclusion, we provide evidence that NDGA improves metabolic dysregulation by simultaneously modulating PPARα transcription factor and key genes involved in fatty acid oxidation, key antioxidant and lipogenic enzymes, and apoptosis and ER stress signaling pathways.

    View details for PubMedID 29472517

  • A Dominant Role for Regulatory T Cells in Protecting Females Against Pulmonary Hypertension. Circulation research Tamosiuniene, R., Manouvakhova, O., Mesange, P., Saito, T., Qian, J., Sanyal, M., Lin, Y. C., Nguyen, L. P., Luria, A., Tu, A. B., Sante, J. M., Rabinovitch, M., Fitzgerald, D. J., Graham, B. B., Habtezion, A., Voelkel, N. F., Aurelian, L., Nicolls, M. R. 2018

    Abstract

    Rationale: Pulmonary arterial hypertension (PH) is a life-threatening condition associated with immune dysregulation and abnormal regulatory T cell (Treg) activity, but it is currently unknown whether and how abnormal Treg function differentially affects males and females. Objective: To evaluate whether and how Treg-deficiency differentially affects male and female rats in experimental PH. Methods and Results: Male and female athymicrnu/rnurats, lacking Tregs, were treated with the vascular endothelial growth factor receptor-2 (VEGFR2) inhibitor SU5416 or chronic hypoxia and evaluated for PH; some animals underwent Treg immune reconstitution (IR) before SU5416 administration. Plasma prostacyclin (PGI2) levels were measured. Lung and right ventricles (RVs) were assessed for the expression of the vasoprotective proteins cyclooxygenase-2 (COX-2), prostacyclin synthase (PTGIS), programmed death ligand-1 (PDL-1), and heme oxygenase-1 (HO-1). Inhibitors of these pathways were administered to athymic rats undergoing Treg IR. Finally, human cardiac microvascular endothelial cells co-cultured with Tregs were evaluated for COX-2, PDL-1, HO-1, and estrogen receptor (ER) expression, and culture supernatants were assayed for PGI2 and IL-10. SU5416-treatment and chronic hypoxia produced more severe PH in female than male athymic rats. Females were distinguished by greater pulmonary inflammation, augmented RV fibrosis, lower plasma PGI2 levels, decreased lung COX-2, PTGIS, HO-1 and PDL-1 expression and reduced RV PDL-1 levels. In both sexes, Treg IR protected against PH development and raised levels of plasma PGI2 and cardiopulmonary COX-2, PTGIS, PDL-1, and HO-1. Inhibiting COX-2, HO-1, and programmed death-1 (PD1)/PDL1 pathways abrogated Treg protection. In vitro, human Tregs directly upregulated endothelial COX-2, PDL1, HO-1, ERs and increased supernatant levels of PGI2 and IL-10. Conclusions: In two animal models of PH based on Treg deficiency, females developed more severe PH than males. The data suggest that females are especially reliant on normal Treg function to counteract the effects of pulmonary vascular injury leading to PH.

    View details for PubMedID 29545367

  • Dynamics of the human antibody repertoire after B cell depletion in systemic sclerosis SCIENCE IMMUNOLOGY de Bourcy, C. A., Dekker, C. L., Davis, M. M., Nicolls, M. R., Quake, S. R. 2017; 2 (15)
  • The Roles of Immunity in the Prevention and Evolution of Pulmonary Arterial Hypertension AMERICAN JOURNAL OF RESPIRATORY AND CRITICAL CARE MEDICINE Nicolls, M. R., Voelkel, N. F. 2017; 195 (10): 1292-1299

    Abstract

    This Perspective provides an in depth overview of the many aspects of inflammation which are associated with many forms of severe pulmonary hypertension.Details of the pathobiology of severe pulmonary hypertension are discussed in the context of the multicellular inflammatory vascular infiltrates which represent a lung vessel response to injury and and a localized immune response.The important question whether inflammation is cause or consequence of pulmonary hypertension should not distract from designing and conducting clinical pilot studies which examine the efficacy of existing immune system modulating drugs.

    View details for DOI 10.1164/rccm.201608-1630PP

    View details for Web of Science ID 000401501400008

  • Leukotriene B-4 antagonism ameliorates experimental lymphedema SCIENCE TRANSLATIONAL MEDICINE Tian, W., Rockson, S. G., Jiang, X., Kim, J., Begaye, A., Shuffle, E. M., Tu, A. B., Cribb, M., Nepiyushchikh, Z., Feroze, A. H., Zamanian, R. T., Dhillon, G. S., Voelkel, N. F., Peters-Golden, M., Kitajewski, J., Dixon, J. B., Nicolls, M. R. 2017; 9 (389)
  • Simultaneously Targeting Myofibroblast Contractility and Extracellular Matrix Cross-Linking as a Therapeutic Concept in Airway Fibrosis AMERICAN JOURNAL OF TRANSPLANTATION Lin, Y., Sung, Y. K., Jiang, X., Peters-Golden, M., Nicolls, M. R. 2017; 17 (5): 1229-1241

    Abstract

    Fibrosis after solid organ transplantation is considered an irreversible process and remains the major cause of graft dysfunction and death with limited therapies. This remodeling is characterized by aberrant accumulation of contractile myofibroblasts that deposit excessive extracellular matrix (ECM) and increase tissue stiffness. However, studies demonstrate that a stiff ECM, itself, promotes fibroblast-to-myofibroblast differentiation, stimulating further ECM production. This creates a positive feedback loop that perpetuates fibrosis. We hypothesized that simultaneously targeting myofibroblast contractility with relaxin and ECM stiffness with lysyl oxidase inhibitors could break the feedback loop, thereby, reversing established fibrosis. To test this, we used the orthotopic tracheal transplanted (OTT) mouse model, which develops robust fibrotic airway remodeling. Mice with established fibrosis were treated with saline, mono-, or combination therapies. While monotherapies had no effect, combining these agents decreased collagen deposition and promoted re-epithelialization of remodeled airways. Relaxin inhibited myofibroblast differentiation and contraction, in a matrix-stiffness-dependent manner through prostaglandin E2 (PGE2 ). Furthermore, the effect of combination therapy was lost in PGE2 receptor knockout and PGE2 inhibited OTT mice. This study reveals the important synergistic roles of cellular contractility and tissue stiffness in the maintenance of fibrotic tissue and suggests a new therapeutic principle for fibrosis. This article is protected by copyright. All rights reserved.

    View details for DOI 10.1111/ajt.14103

    View details for Web of Science ID 000400382300012

  • Microvascular Integrity Can Be Preserved by Anti-Platelet Therapy and in Combination with mTOR Inhibitor Heim, C., Khan, M. A., Motsch, B., Gocht, A., Ramsperger-Gleixner, M., Stamminger, T., Nicolls, M. R., Weyand, M., Ensminger, S. M. ELSEVIER SCIENCE INC. 2017: S376
  • Donor-Derived Cell-Free DNA Associates with Rejection in Lung Transplantation Using Clinical-Grade Targeted Next-Generation Sequencing Khush, K. K., Beausang, J. F., Woodward, R. N., Lew, D., Sninsky, J., De Vlaminck, I., Strehl, C., Luikart, H., Nicolls, M., Weill, D. ELSEVIER SCIENCE INC. 2017: S146
  • Translating Research into Improved Patient Care in Pulmonary Arterial Hypertension AMERICAN JOURNAL OF RESPIRATORY AND CRITICAL CARE MEDICINE Bonnet, S., Provencher, S., Guignabert, C., Perros, F., Boucherat, O., Schermuly, R. T., Hassoun, P. M., Rabinovitch, M., Nicolls, M. R., Humbert, M. 2017; 195 (5): 583-595

    Abstract

    Despite important advances in its therapeutic management, pulmonary arterial hypertension (PAH) remains an incurable disease. Although numerous drugs exhibited beneficial effects in preclinical settings, only few have reached clinical trial phases, highlighting the challenges of translating preclinical investigations into clinical trials. Potential reasons for delayed PAH drug development may include the inherent limitations of the currently available animal and in vitro models, potential lack of appropriate standardization of the experimental design, regulatory agencies requirements, competing clinical trials and insufficient funding. Although this is not unique to PAH, there is urgency for reducing the number of false positive signals in preclinical studies and optimizing the development of innovative therapeutic targets through performance of clinical trials based on more robust experimental data. The current review discusses the challenges and opportunities in preclinical research to foster drug development in PAH.

    View details for DOI 10.1164/rccm.201607-1515PP

    View details for Web of Science ID 000395357400008

  • Discovery Of Proteomic Immune Signatures In Pulmonary Arterial Hypertension By Unsupervised Consensus Clustering Sweatt, A., Hedlin, H., Balasubramanian, V., Hsi, A., Blum, L., Robinson, W., Nicolls, M. R., Rabinovitch, M., Khatri, P., Zamanian, R. T. AMER THORACIC SOC. 2017
  • Hypoxia Inducible Factor-1 alpha Increases Bone Morphogenetic Protein Receptor 2 Signaling In Pulmonary Artery Endothelial Cells (paecs) Kuang, J., Tian, X., Prosseda, S., Tian, A., Cornfield, D., Nicolls, M. R., Spiekerkoetter, E. F. AMER THORACIC SOC. 2017
  • Dynamics of the human antibody repertoire after B cell depletion in systemic sclerosis Dynamics of the human antibody repertoire after B cell depletion in systemic sclerosis de Bourcy, C. F., Dekker, C. L., Davis, M. M., Nicolls, M. R., Quake, S. R. 2017; 2 (15)
  • Upregulation of HERV-K is Linked to Immunity and Inflammation in Pulmonary Arterial Hypertension. Circulation Saito, T., Miyagawa, K., Chen, S. Y., Tamosiuniene, R., Wang, L., Sharp, O., Samayoa, E., Harada, D., Moonen, J. A., Cao, A., Chen, P. I., Hennigs, J. K., Gu, M., Li, C. G., Leib, R. D., Li, D., Adams, C. M., Del Rosario, P. A., Bill, M. A., Haddad, F., Montoya, J. G., Robinson, W., Fantl, W. J., Nolan, G. P., Zamanian, R. T., Nicolls, M. R., Chiu, C. Y., Ariza, M. E., Rabinovitch, M. 2017

    Abstract

    Background -Immune dysregulation has been linked to occlusive vascular remodeling in pulmonary arterial hypertension (PAH) that is hereditary, idiopathic or associated with other conditions. Circulating autoantibodies, lung perivascular lymphoid tissue and elevated cytokines have been related to PAH pathogenesis but without clear understanding of how these abnormalities are initiated, perpetuated and connected in the progression of disease. We therefore set out to identify specific target antigens in PAH lung immune complexes as a starting point toward resolving these issues to better inform future application of immunomodulatory therapies. Methods -Lung immune complexes were isolated and PAH target antigens were identified by liquid chromatography tandem mass spectrometry (LCMS), confirmed by ELISA, and localized by confocal microscopy. One PAH antigen linked to immunity and inflammation was pursued and a link to PAH pathophysiology was investigated by next generation sequencing, functional studies in cultured monocytes and endothelial cells (EC) and hemodynamic and lung studies in a rat. Results -SAM domain and HD1 domain-containing protein (SAMHD1), an innate immune factor that suppresses HIV replication was identified and confirmed as highly expressed in immune complexes from 16 hereditary and idiopathic PAH vs. 12 control lungs. Elevated SAMHD1 was localized to endothelial cells (EC), perivascular dendritic cells and macrophages and SAMHD1 antibodies were prevalent in tertiary lymphoid tissue. An unbiased screen using metagenomic sequencing related SAMHD1 to increased expression of human endogenous retrovirus K (HERV-K) in PAH vs. control lungs (n=4 each). HERV-K envelope and deoxyuridine triphosphate nucleotidohydrolase (dUTPase) mRNAs were elevated in PAH vs. control lungs (n=10) and proteins were localized to macrophages. HERV-K dUTPase induced SAMHD1 and pro-inflammatory cytokines (e.g., IL6, IL1β and TNFα) in circulating monocytes and pulmonary arterial (PA) EC, and activated B cells. Vulnerability of PAEC to apoptosis was increased by HERV-K dUTPase in an IL6 independent manner. Furthermore, three weekly injections of HERV-K dUTPase induced hemodynamic and vascular changes of pulmonary hypertension in rats (n=8), and elevated IL6. Conclusions -Our study reveals that upregulation of the endogenous retrovirus HERV-K could both initiate and sustain activation of the immune system and cause vascular changes associated with PAH.

    View details for PubMedID 28935667

  • Lymphatic Dysfunction, Leukotrienes, and Lymphedema. Annual review of physiology Jiang, X., Nicolls, M. R., Tian, W., Rockson, S. G. 2017

    Abstract

    The lymphatic system is essential for the maintenance of tissue fluid homeostasis, gastrointestinal lipid absorption, and immune trafficking. Whereas lymphatic regeneration occurs physiologically in wound healing and tissue repair, pathological lymphangiogenesis has been implicated in a number of chronic diseases such as lymphedema, atherosclerosis, and cancer. Insight into the regulatory mechanisms of lymphangiogenesis and the manner in which uncontrolled inflammation promotes lymphatic dysfunction is urgently needed to guide the development of novel therapeutics: These would be designed to reverse lymphatic dysfunction, either primary or acquired. Recent investigation has demonstrated the mechanistic role of leukotriene B4 (LTB4) in the molecular pathogenesis of lymphedema. LTB4, a product of the innate immune response, is a constituent of the eicosanoid inflammatory mediator family of molecules that promote both physiological and pathological inflammation. Here we provide an overview of lymphatic development, the pathophysiology of lymphedema, and the role of leukotrienes in lymphedema pathogenesis. Expected final online publication date for the Annual Review of Physiology Volume 80 is February 10, 2018. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

    View details for PubMedID 29029593

  • Introduction to the 59th Annual Thomas L. Petty Aspen Lung Conference. Lung Transplantation: Opportunities for Repair and Regeneration. Annals of the American Thoracic Society Zamora, M. R., Martinu, T., Nicolls, M. R. 2017; 14 (Supplement_3): S209

    View details for PubMedID 28945478

  • Dynamics of the human antibody repertoire after B cell depletion in systemic sclerosis. Science immunology de Bourcy, C. F., Dekker, C. L., Davis, M. M., Nicolls, M. R., Quake, S. R. 2017; 2 (15)

    Abstract

    Systemic sclerosis with pulmonary arterial hypertension (SSc-PAH) is a debilitating and frequently lethal disease of unknown cause lacking effective treatment options. Lymphocyte anomalies and autoantibodies observed in systemic sclerosis have suggested an autoimmune character. We study the clonal structure of the B cell repertoire in SSc-PAH using immunoglobulin heavy chain (IGH) sequencing before and after B cell depletion. We found SSc-PAH to be associated with anomalies in B cell development, namely, altered VDJ rearrangement frequencies (reduced IGHV2-5 segment usage) and an increased somatic mutation-fixation probability in expanded B cell lineages. SSc-PAH was also characterized by anomalies in B cell homeostasis, namely, an expanded immunoglobulin D-positive (IgD(+)) proportion with reduced mutation loads and an expanded proportion of highly antibody-secreting cells. Disease signatures pertaining to IGHV2-5 segment usage, IgD proportions, and mutation loads were temporarily reversed after B cell depletion. Analyzing the time course of B cell depletion, we find that the kinetics of naïve replenishment are predictable from baseline measurements alone, that release of plasma cells into the periphery can precede naïve replenishment, and that modes of B cell receptor diversity are highly elastic. Our findings reveal humoral immune signatures of SSc-PAH and uncover determinism in the effects of B cell depletion on the antibody repertoire.

    View details for PubMedID 28963118

  • Aspergillus-related pulmonary diseases in lung transplantation MEDICAL MYCOLOGY Pasupneti, S., Manouvakhova, O., Nicolls, M. R., Hsu, J. L. 2017; 55 (1): 96-102

    Abstract

    While lung transplantation is an attractive treatment option for many end stage lung diseases, the relatively high 5-year mortality continues to be a significant limiting factor. Among the foremost reasons for this is the eventual development of obstructive chronic lung allograft dysfunction. Infections, which the lung allograft is especially prone to, are a major risk factor. Specifically, the Aspergillus species cause a higher burden of disease among lung transplant recipients, due to unique risk factors, such as relative hypoxemia. However, these risk factors also provide unique opportunities for treatment and preventative strategies, as outlined in this review.

    View details for DOI 10.1093/mmy/myw121

    View details for Web of Science ID 000393896500013

  • Models of Lung Transplant Research: a consensus statement from the National Heart, Lung, and Blood Institute workshop. JCI insight Lama, V. N., Belperio, J. A., Christie, J. D., El-Chemaly, S., Fishbein, M. C., Gelman, A. E., Hancock, W. W., Keshavjee, S., Kreisel, D., Laubach, V. E., Looney, M. R., McDyer, J. F., Mohanakumar, T., Shilling, R. A., Panoskaltsis-Mortari, A., Wilkes, D. S., Eu, J. P., Nicolls, M. R. 2017; 2 (9)

    Abstract

    Lung transplantation, a cure for a number of end-stage lung diseases, continues to have the worst long-term outcomes when compared with other solid organ transplants. Preclinical modeling of the most common and serious lung transplantation complications are essential to better understand and mitigate the pathophysiological processes that lead to these complications. Various animal and in vitro models of lung transplant complications now exist and each of these models has unique strengths. However, significant issues, such as the required technical expertise as well as the robustness and clinical usefulness of these models, remain to be overcome or clarified. The National Heart, Lung, and Blood Institute (NHLBI) convened a workshop in March 2016 to review the state of preclinical science addressing the three most important complications of lung transplantation: primary graft dysfunction (PGD), acute rejection (AR), and chronic lung allograft dysfunction (CLAD). In addition, the participants of the workshop were tasked to make consensus recommendations on the best use of these complimentary models to close our knowledge gaps in PGD, AR, and CLAD. Their reviews and recommendations are summarized in this report. Furthermore, the participants outlined opportunities to collaborate and directions to accelerate research using these preclinical models.

    View details for PubMedID 28469087

  • Leukotriene B4 Potentiates Bmpr2 Deficiency And Causes Paec Endmt In Pah Tian, A., Jiang, X., Shuffle, E., Tu, A., Jin, Q., Zamanian, R. T., Voelkel, N., Peters-Golden, M., Tuder, R., Rabinovitch, M., Nicolls, M. AMER THORACIC SOC. 2017
  • Delivery Of Il-10 Using A Novel High Molecular Weight Hyaluronan Vehicle Reduces Lung Fibrosis In A Bleomycin Mouse Model Of Lung Injury Shamskhou, E., Orcholski, M., Kaber, G., Yuan, K., Danielson, B., Chapman, H., Nicolls, M., Bollyky, P., Perez, V. AMER THORACIC SOC. 2017
  • Clinical Heterogeneity Across Proteomic Immunophenotypes In Pulmonary Arterial Hypertension Sweatt, A., Hedlin, H., Balasubramanian, V., Hsi, A., Blum, L., Robinson, W., Nicolls, M., Rabinovitch, M., Khatri, P., Zamanian, R. T. AMER THORACIC SOC. 2017
  • Simultaneously Targeting Myofibroblast Contractility and Extracellular Matrix Cross-Linking as a Therapeutic Concept in Airway Fibrosis. American journal of transplantation Lin, Y., Sung, Y. K., Jiang, X., Peters-Golden, M., Nicolls, M. R. 2016

    Abstract

    Fibrosis after solid organ transplantation is considered an irreversible process and remains the major cause of graft dysfunction and death with limited therapies. This remodeling is characterized by aberrant accumulation of contractile myofibroblasts that deposit excessive extracellular matrix (ECM) and increase tissue stiffness. However, studies demonstrate that a stiff ECM, itself, promotes fibroblast-to-myofibroblast differentiation, stimulating further ECM production. This creates a positive feedback loop that perpetuates fibrosis. We hypothesized that simultaneously targeting myofibroblast contractility with relaxin and ECM stiffness with lysyl oxidase inhibitors could break the feedback loop, thereby, reversing established fibrosis. To test this, we used the orthotopic tracheal transplanted (OTT) mouse model, which develops robust fibrotic airway remodeling. Mice with established fibrosis were treated with saline, mono-, or combination therapies. While monotherapies had no effect, combining these agents decreased collagen deposition and promoted re-epithelialization of remodeled airways. Relaxin inhibited myofibroblast differentiation and contraction, in a matrix-stiffness-dependent manner through prostaglandin E2 (PGE2 ). Furthermore, the effect of combination therapy was lost in PGE2 receptor knockout and PGE2 inhibited OTT mice. This study reveals the important synergistic roles of cellular contractility and tissue stiffness in the maintenance of fibrotic tissue and suggests a new therapeutic principle for fibrosis. This article is protected by copyright. All rights reserved.

    View details for DOI 10.1111/ajt.14103

    View details for PubMedID 27804215

  • Enhanced Electrochemical Sensing with Carbon Nanotubes Modified with Bismuth and Magnetic Nanoparticles in a Lab-on-a-Chip CHEMNANOMAT Jothimuthu, P., Hsu, J. L., Chen, R., Inayathullah, M., Pothineni, V. R., Jan, A., Gurtner, G. C., Rajadas, J., Nicolls, M. R. 2016; 2 (9): 904-910

    Abstract

    Iron plays an especially important role in human physiological functions and pathological impairments. The superior properties of carbon nanotubes (CNTs) and their modification with bismuth and magnetic nanoparticles as developed in this work have led to an extraordinary and novel material to facilitate ultrasensitive detection in the nanomolar range. Here, we present the development of an electrochemical sensor for detection of ferrous (Fe(2+)) and ferric (Fe(3+)) iron by means of CNTs modified with bismuth and magnetic nanoparticles for higher sensitivity of detection. The sensor fabrication includes microfabrication methodologies, soft lithography, and electrodeposition. Cyclic voltammetry and differential pulse voltammetry are used for the electroanalytical studies and detection of the ions in samples. The sensor has a dynamic range of detection from 0.01 nm to 10 mm. The performance of the sensor with modified CNTs was explored for sensitivity and specificity. CNTs, modified with bismuth and magnetic nanoparticles by means of electrodeposition, enhanced the detection limit significantly down to 0.01 nm.

    View details for DOI 10.1002/cnma.201600174

    View details for Web of Science ID 000383766800009

    View details for PubMedCentralID PMC5110256

  • Challenges and opportunities in treating inflammation associated with pulmonary hypertension. Expert review of cardiovascular therapy Voelkel, N. F., Tamosiuniene, R., Nicolls, M. R. 2016; 14 (8): 939-951

    Abstract

    Inflammatory cells are present in the lungs from patients with many, if not all, forms of severe pulmonary hypertension. Historically the first inflammatory cell identified in the pulmonary vascular lesions was the mast cell. T and B lymphocytes, as well as macrophages, are present in and around the pulmonary arterioles and many patients have elevated blood levels of interleukin 1 and 6; some patients show elevated levels of leukotriene B4. An overlap between collagen-vascular disease-associated pulmonary arterial hypertension (PAH) and idiopathic PAH exists, yet only a few studies have been designed that evaluate the effect of anti-inflammatory treatments. Here we review the pertinent data that connect PAH and inflammation/immune dysregulation and evaluate experimental models of severe PAH with an emphasis on the Sugen/athymic rat model of severe PAH. We postulate that there are more than one inflammatory phenotype and predict that there will be several anti-inflammatory treatment strategies for severe PAH.

    View details for DOI 10.1080/14779072.2016.1180976

    View details for PubMedID 27096622

  • Effect of Transplant Center Volume on Cost and Readmissions in Medicare Lung Transplant Recipients. Annals of the American Thoracic Society Mooney, J. J., Weill, D., Boyd, J. H., Nicolls, M. R., Bhattacharya, J., Dhillon, G. S. 2016; 13 (7): 1034-1041

    Abstract

    While lung transplant recipient survival is better at higher volume centers, the effect of center volume on admission cost and early hospital readmission is unknown.To understand the association between transplant center volume and recipient risk-adjusted transplant admission cost, in-hospital mortality, and early hospital readmission in lung transplant recipients.Medicare lung transplant recipients from May 4, 2005 to December 31, 2011 were identified through linkage of transplant registry and Medicare administrative claims. Transplant admission cost was extracted, adjusted for regional price variation, and compared across low, intermediate, and high volume centers. A multivariable hierarchical generalized linear regression model was used to assess the effect of transplant center volume on recipient adjusted cost. Modified Poisson regression models were used to assess adjusted in-hospital mortality and early hospital readmission by transplant center volume.There were 3,128 Medicare lung transplant recipients identified. Unadjusted transplant cost was lower at high volume centers (mean

  • Microvascular injury after lung transplantation CURRENT OPINION IN ORGAN TRANSPLANTATION Nicolls, M. R., Hsu, J. L., Jiang, X. 2016; 21 (3): 279-284

    Abstract

    Airway microvessel injury following transplantation has been implicated in the development of chronic rejection. This review focuses on the most recent developments in the field describing preclinical and clinical findings that further implicate the loss of microvascular integrity as an important pathological event in the evolution of irreversible fibrotic remodeling.When lungs are transplanted, the airways appear vulnerable from the perspective of perfusion. Two vascular systems are lost, the bronchial artery and the lymphatic circulations, and the remaining vasculature in the airways expresses donor antigens susceptible to alloimmune-mediated injury via innate and adaptive immune mechanisms. Preclinical studies indicate the importance of hypoxia-inducible factor-1α in mediating microvascular repair and that hypoxia-inducible factor-1α can be upregulated to bolster endogenous repair.Airway microvascular injury is a feature of lung transplantation that limits short-term and long-term organ health. Although some problems are attributable to a missing bronchial artery circulation, another significant issue involves alloimmune-mediated injury to transplant airway microvessels. For a variety of reasons, bronchial artery revascularization surgery at the time of transplantation has not been widely adopted, and the current best hope for this era may be new medical approaches that offer protection against immune-mediated vascular injury or that promote microvascular repair.

    View details for DOI 10.1097/MOT.0000000000000307

    View details for Web of Science ID 000376015500007

    View details for PubMedID 26967995

  • Lung Quality and Utilization in Controlled Donation After Circulatory Determination of Death Within the United States AMERICAN JOURNAL OF TRANSPLANTATION Mooney, J. J., Hedlin, H., Mohabir, P. K., Vazquez, R., Nguyen, J., Ha, R., Chiu, P., Patel, K., Zamora, M. R., Weill, D., Nicolls, M. R., Dhillon, G. S. 2016; 16 (4): 1207-1215

    Abstract

    Although controlled donation after circulatory determination of death (cDCDD) could increase the supply of donor lungs within the United States, the yield of lungs from cDCDD donors remains low compared with donation after neurologic determination of death (DNDD). To explore the reason for low lung yield from cDCDD donors, Scientific Registry of Transplant Recipient data were used to assess the impact of donor lung quality on cDCDD lung utilization by fitting a logistic regression model. The relationship between center volume and cDCDD use was assessed, and the distance between center and donor hospital was calculated by cDCDD status. Recipient survival was compared using a multivariable Cox regression model. Lung utilization was 2.1% for cDCDD donors and 21.4% for DNDD donors. Being a cDCDD donor decreased lung donation (adjusted odds ratio 0.101, 95% confidence interval [CI] 0.085-0.120). A minority of centers have performed cDCDD transplant, with higher volume centers generally performing more cDCDD transplants. There was no difference in center-to-donor distance or recipient survival (adjusted hazard ratio 1.03, 95% CI 0.78-1.37) between cDCDD and DNDD transplants. cDCDD lungs are underutilized compared with DNDD lungs after adjusting for lung quality. Increasing transplant center expertise and commitment to cDCDD lung procurement is needed to improve utilization.

    View details for DOI 10.1111/ajt.13599

    View details for Web of Science ID 000373075400021

  • A Critical Role for Airway Microvessels in Lung Transplantation. American journal of respiratory and critical care medicine Nicolls, M. R., Dhillon, G. S., Daddi, N. 2016; 193 (5): 479-481

    View details for DOI 10.1164/rccm.201511-2117ED

    View details for PubMedID 26930430

  • Limitations Of Pulmonary Vascular Resistance As A Primary Endpoint For Therapeutic Trials Of Systemic Sclerosis Associated Pulmonary Arterial Hypertension Zamanian, R. T., Rhee, R., Pinckney, A., Goldmuntz, E., Welch, B., D'Aveta, C., Badesch, D., Nicolls, M., Kawut, S. M., Spychala, M., Autoimmunity Ctr Excellence ASC01 AMER THORACIC SOC. 2016
  • Circulating Elastase Confers A High Risk For The Development Of Bronchiolitis Obliterans Syndrome Milla, C. E., Zirbes, J. M., Yacob, A., Tian, L., Zamanian, R. T., Bental-Roof, M., Bland, R., Rabinovitch, M., Dhillon, G., Nicolls, M. AMER THORACIC SOC. 2016
  • Lung Quality and Utilization in Controlled Donation After Circulatory Determination of Death Within the United States. American journal of transplantation : official journal of the American Society of Transplantation and the American Society of Transplant Surgeons Mooney, J. J., Hedlin, H., Mohabir, P. K., Vazquez, R., Nguyen, J., Ha, R., Chiu, P., Patel, K., Zamora, M. R., Weill, D., Nicolls, M. R., Dhillon, G. S. 2016

    Abstract

    Although controlled donation after circulatory determination of death (cDCDD) could increase the supply of donor lungs within the United States, the yield of lungs from cDCDD donors remains low compared with donation after neurologic determination of death (DNDD). To explore the reason for low lung yield from cDCDD donors, Scientific Registry of Transplant Recipient data were used to assess the impact of donor lung quality on cDCDD lung utilization by fitting a logistic regression model. The relationship between center volume and cDCDD use was assessed, and the distance between center and donor hospital was calculated by cDCDD status. Recipient survival was compared using a multivariable Cox regression model. Lung utilization was 2.1% for cDCDD donors and 21.4% for DNDD donors. Being a cDCDD donor decreased lung donation (adjusted odds ratio 0.101, 95% confidence interval [CI] 0.085-0.120). A minority of centers have performed cDCDD transplant, with higher volume centers generally performing more cDCDD transplants. There was no difference in center-to-donor distance or recipient survival (adjusted hazard ratio 1.03, 95% CI 0.78-1.37) between cDCDD and DNDD transplants. cDCDD lungs are underutilized compared with DNDD lungs after adjusting for lung quality. Increasing transplant center expertise and commitment to cDCDD lung procurement is needed to improve utilization.

    View details for PubMedID 26844673

  • Enhanced Electrochemical Sensing with Carbon Nanotubes Modified with Bismuth and Magnetic Nanoparticles in a Lab-on-a-Chip. ChemNanoMat : chemistry of nanomaterials for energy, biology and more Jothimuthu, P., Hsu, J. L., Chen, R., Inayathullah, M., Pothineni, V. R., Jan, A., Gurtner, G. C., Rajadas, J., Nicolls, M. R. 2016; 2 (9): 904–10

    Abstract

    Iron plays an especially important role in human physiological functions and pathological impairments. The superior properties of carbon nanotubes (CNTs) and their modification with bismuth and magnetic nanoparticles as developed in this work have led to an extraordinary and novel material to facilitate ultrasensitive detection in the nanomolar range. Here, we present the development of an electrochemical sensor for detection of ferrous (Fe(2+)) and ferric (Fe(3+)) iron by means of CNTs modified with bismuth and magnetic nanoparticles for higher sensitivity of detection. The sensor fabrication includes microfabrication methodologies, soft lithography, and electrodeposition. Cyclic voltammetry and differential pulse voltammetry are used for the electroanalytical studies and detection of the ions in samples. The sensor has a dynamic range of detection from 0.01 nm to 10 mm. The performance of the sensor with modified CNTs was explored for sensitivity and specificity. CNTs, modified with bismuth and magnetic nanoparticles by means of electrodeposition, enhanced the detection limit significantly down to 0.01 nm.

    View details for PubMedID 27857882

  • Bmpr2 Deficiency Potentiates The Ltb4 Mediated Paec Transformation In Pah Tian, W., Jiang, X., Qian, J., Tu, A., Shuffle, E., Mesange, P., Nicolls, M. AMER THORACIC SOC. 2016
  • Inhibition Of Connective Tissue Growth Factor Promotes Healthy Revascularization And Ameliorates Fibrosis In Orthotopic Tracheal Transplantation Lin, Y., Jiang, X., Nicolls, M. AMER THORACIC SOC. 2016
  • Acute Microvascular Rejection Increases Graft Iron, Promoting Aspergillus Fumigatus Allograft Invasion Hsu, J. L., Inayathulla, M., Tu, A. B., Clemons, K. V., Rajadas, J., Stevens, D. A., Nicolls, M. AMER THORACIC SOC. 2016
  • Endothelial Hif-2a Deficiency Disrupts Airway Microvascular Structure And Impairs The Repair Of Vessels Of Transplanted Airways Jiang, X., Tian, W., Tu, A., Nicolls, M. AMER THORACIC SOC. 2016
  • Leukotriene B-4 Activates Pulmonary Artery Adventitial Fibroblasts in Pulmonary Hypertension HYPERTENSION Qian, J., Tian, W., Jiang, X., Tamosiuniene, R., Sung, Y. K., Shuffle, E. M., Tu, A. B., Valenzuela, A., Jiang, S., Zamanian, R. T., Fiorentino, D. F., Voelkel, N. F., Peters-Golden, M., Stenmark, K. R., Chung, L., Rabinovitch, M., Nicolls, M. R. 2015; 66 (6): 1227-1239

    Abstract

    A recent study demonstrated a significant role for leukotriene B4 (LTB4) causing pulmonary vascular remodeling in pulmonary arterial hypertension. LTB4 was found to directly injure luminal endothelial cells and promote growth of the smooth muscle cell layer of pulmonary arterioles. The purpose of this study was to determine the effects of LTB4 on the pulmonary adventitial layer, largely composed of fibroblasts. Here, we demonstrate that LTB4 enhanced human pulmonary artery adventitial fibroblast proliferation, migration, and differentiation in a dose-dependent manner through its cognate G-protein-coupled receptor, BLT1. LTB4 activated human pulmonary artery adventitial fibroblast by upregulating p38 mitogen-activated protein kinase as well as Nox4-signaling pathways. In an autoimmune model of pulmonary hypertension, inhibition of these pathways blocked perivascular inflammation, decreased Nox4 expression, reduced reactive oxygen species production, reversed arteriolar adventitial fibroblast activation, and attenuated pulmonary hypertension development. This study uncovers a novel mechanism by which LTB4 further promotes pulmonary arterial hypertension pathogenesis, beyond its established effects on endothelial and smooth muscle cells, by activating adventitial fibroblasts.

    View details for DOI 10.1161/HYPERTENSIONAHA.115.06370

    View details for PubMedID 26558820

  • Noninvasive monitoring of infection and rejection after lung transplantation. Proceedings of the National Academy of Sciences of the United States of America De Vlaminck, I., Martin, L., Kertesz, M., Patel, K., Kowarsky, M., Strehl, C., Cohen, G., Luikart, H., Neff, N. F., Okamoto, J., Nicolls, M. R., Cornfield, D., Weill, D., Valantine, H., Khush, K. K., Quake, S. R. 2015; 112 (43): 13336-13341

    Abstract

    The survival rate following lung transplantation is among the lowest of all solid-organ transplants, and current diagnostic tests often fail to distinguish between infection and rejection, the two primary posttransplant clinical complications. We describe a diagnostic assay that simultaneously monitors for rejection and infection in lung transplant recipients by sequencing of cell-free DNA (cfDNA) in plasma. We determined that the levels of donor-derived cfDNA directly correlate with the results of invasive tests of rejection (area under the curve 0.9). We also analyzed the nonhuman cfDNA as a hypothesis-free approach to test for infections. Cytomegalovirus is most frequently assayed clinically, and the levels of CMV-derived sequences in cfDNA are consistent with clinical results. We furthermore show that hypothesis-free monitoring for pathogens using cfDNA reveals undiagnosed cases of infection, and that certain infectious pathogens such as human herpesvirus (HHV) 6, HHV-7, and adenovirus, which are not often tested clinically, occur with high frequency in this cohort.

    View details for DOI 10.1073/pnas.1517494112

    View details for PubMedID 26460048

  • Cyclosporine Does Not Prevent Microvascular Loss in Transplantation but Can Synergize With a Neutrophil Elastase Inhibitor, Elafin, to Maintain Graft Perfusion During Acute Rejection AMERICAN JOURNAL OF TRANSPLANTATION Jiang, X., Nguyen, T. T., Tian, W., Sung, Y. K., Yuan, K., Qian, J., Rajadas, J., Sallenave, J., Nickel, N. P., Perez, V. d., RABINOVITCH, M., Nicolls, M. R. 2015; 15 (7): 1768-1781

    Abstract

    The loss of a functional microvascular bed in rejecting solid organ transplants is correlated with fibrotic remodeling and chronic rejection; in lung allografts, this pathology is predicted by bronchoalveolar fluid neutrophilia which suggests a role for polymorphonuclear cells in microcirculatory injury. In a mouse orthotopic tracheal transplant model, cyclosporine, which primarily inhibits T cells, failed as a monotherapy for preventing microvessel rejection and graft ischemia. To target neutrophil action that may be contributing to vascular injury, we examined the effect of a neutrophil elastase inhibitor, elafin, on the microvascular health of transplant tissue. We showed that elafin monotherapy prolonged microvascular perfusion and enhanced tissue oxygenation while diminishing the infiltration of neutrophils and macrophages and decreasing tissue deposition of complement C3 and the membrane attack complex, C5b-9. Elafin was also found to promote angiogenesis through activation of the extracellular signal-regulated kinase (ERK) signaling pathway but was insufficient as a single agent to completely prevent tissue ischemia during acute rejection episodes. However, when combined with cyclosporine, elafin effectively preserved airway microvascular perfusion and oxygenation. The therapeutic strategy of targeting neutrophil elastase activity alongside standard immunosuppression during acute rejection episodes may be an effective approach for preventing the development of irreversible fibrotic remodeling.

    View details for DOI 10.1111/ajt.13189

    View details for Web of Science ID 000356494300013

    View details for PubMedID 25727073

  • Elafin Reverses Pulmonary Hypertension via Caveolin-1-Dependent Bone Morphogenetic Protein Signaling AMERICAN JOURNAL OF RESPIRATORY AND CRITICAL CARE MEDICINE Nickel, N. P., Spiekerkoetter, E., Gu, M., Li, C. G., Li, H., Kaschwich, M., Diebold, I., Hennigs, J. K., Kim, K., Miyagawa, K., Wang, L., Cao, A., Sa, S., Jiang, X., Stockstill, R. W., Nicolls, M. R., Zamanian, R. T., Bland, R. D., Rabinovitch, M. 2015; 191 (11): 1273-1286

    Abstract

    Pulmonary arterial hypertension is characterized by endothelial cell dysfunction, impaired BMPR2 signaling, and increased elastase activity. Synthetic elastase inhibitors reverse experimental pulmonary hypertension but cause hepatotoxicity in clinical studies. The endogenous elastase inhibitor elafin attenuates the development of hypoxic pulmonary hypertension in mice, but its potential to improve endothelial cell function and BMPR2 signaling, and to reverse severe experimental pulmonary hypertension or vascular pathology in the human disease was unknown.To assess elafin-mediated regression of pulmonary vascular pathology in rats with pulmonary hypertension induced by VEGF receptor blockade and hypoxia (Sugen/Hypoxia), and in lung explants from pulmonary hypertension patients. To determine if elafin amplifies BMPR2 signaling in pulmonary artery endothelial cells from controls and patients, and to elucidate the underlying mechanism. Methods, Measurements and Main Results: In Sugen/Hypoxia rats, elafin reduced elastase activity and reversed pulmonary hypertension, judged by regression of right ventricular systolic pressure and hypertrophy and pulmonary artery occlusive changes. Elafin improved endothelial function by increasing apelin, a product of BMPR2 signaling. Elafin induced apoptosis in human pulmonary arterial smooth muscle cells and in lung organ culture elafin decreased neointimal lesions. In normal and patient pulmonary artery endothelial cells, elafin enhanced survival and promoted angiogenesis by increasing pSMAD dependent and independent BMPR2 signaling. This was linked mechanistically to augmented interaction of BMPR2 with caveolin-1 via elafin-mediated stabilization of caveolin-1 on endothelial surfaces.Elafin reverses obliterative changes in rat and human pulmonary arteries via elastase inhibition and caveolin-1 dependent amplification of BMPR2 signaling.

    View details for DOI 10.1164/rccm.201412-2291OC

    View details for Web of Science ID 000356105000014

    View details for PubMedID 25853696

  • Non-Invasive Monitoring of Infection and Rejection After Lung Transplantation Vlaminck, I. D., Martin, L., Kertesz, M., Patel, K. N., Kowarsky, M., Strehl, C., Cohen, G., Luikart, H., Neff, N., Okamoto, J., Nicolls, M. N., Cornfield, D. N., Weill, D., Valantine, H. A., Khush, K. K., Quake, S. R. ELSEVIER SCIENCE INC. 2015: S137
  • Increased Resource Use in Lung Transplant Admissions in the Lung Allocation Score Era AMERICAN JOURNAL OF RESPIRATORY AND CRITICAL CARE MEDICINE Maxwelll, B. G., Mooney, J. J., Lee, P. H., Levitt, J. E., Chhatwani, L., Nicolls, M. R., Zamora, M. R., Valentine, V., Weill, D., Dhillon, G. S. 2015; 191 (3): 302-308

    Abstract

    Rationale: In 2005, the lung allocation score (LAS) was implemented to prioritize organ allocation to minimize waiting-list mortality and maximize one-year survival. It resulted in transplantation of older and sicker patients without changing one-year survival. Its effect on resource utilization is unknown. Objective: To determine changes in resource utilization over time in lung transplant admissions Methods: Solid organ transplant recipients were identified within the Nationwide Inpatient Sample (NIS) data from 2000 to 2011. Joinpoint regression methodology was performed to identify a time point of change in mean total hospital charges amongst lung transplant and other solid organ transplant recipients. Two temporal lung transplant recipient cohorts identified by joinpoint regression were compared for baseline characteristics and resource utilization, including total charges for index hospitalization, charges per day, length of stay, discharge disposition, tracheostomy, and need for extracorporeal membrane oxygenation (ECMO). Measurements and Main Results: A significant point of increased total hospital charges occurred for lung transplant recipients in 2005, corresponding to LAS implementation, that was not seen in other solid organ transplant recipients. Total transplant hospital charges increased by 40% in the post-LAS cohort [

  • Activation of the Wnt/Planar Cell Polarity Pathway Is Required for Pericyte Recruitment during Pulmonary Angiogenesis. American journal of pathology Yuan, K., Orcholski, M. E., Panaroni, C., Shuffle, E. M., Huang, N. F., Jiang, X., Tian, W., Vladar, E. K., Wang, L., Nicolls, M. R., Wu, J. Y., de Jesus Perez, V. A. 2015; 185 (1): 69-84

    Abstract

    Pericytes are perivascular cells localized to capillaries that promote vessel maturation, and their absence can contribute to vessel loss. Whether impaired endothelial-pericyte interaction contributes to small vessel loss in pulmonary arterial hypertension (PAH) is unclear. Using 3G5-specific, immunoglobulin G-coated magnetic beads, we isolated pericytes from the lungs of healthy subjects and PAH patients, followed by lineage validation. PAH pericytes seeded with healthy pulmonary microvascular endothelial cells failed to associate with endothelial tubes, resulting in smaller vascular networks compared to those with healthy pericytes. After the demonstration of abnormal polarization toward endothelium via live-imaging and wound-healing studies, we screened PAH pericytes for abnormalities in the Wnt/planar cell polarity (PCP) pathway, which has been shown to regulate cell motility and polarity in the pulmonary vasculature. PAH pericytes had reduced expression of frizzled 7 (Fzd7) and cdc42, genes crucial for Wnt/PCP activation. With simultaneous knockdown of Fzd7 and cdc42 in healthy pericytes in vitro and in a murine model of angiogenesis, motility and polarization toward pulmonary microvascular endothelial cells were reduced, whereas with restoration of both genes in PAH pericytes, endothelial-pericyte association was improved, with larger vascular networks. These studies suggest that the motility and polarity of pericytes during pulmonary angiogenesis are regulated by Wnt/PCP activation, which can be targeted to prevent vessel loss in PAH.

    View details for DOI 10.1016/j.ajpath.2014.09.013

    View details for PubMedID 25447046

  • Activation of the Wnt/Planar Cell Polarity Pathway Is Required for Pericyte Recruitment during Pulmonary Angiogenesis AMERICAN JOURNAL OF PATHOLOGY Yuan, K., Orcholski, M. E., Panaroni, C., Shuffle, E. M., Huang, N. F., Jiang, X., Tian, W., Vladar, E. K., Wang, L., Nicolls, M. R., Wu, J. Y., Perez, V. A. 2015; 185 (1): 69-84

    Abstract

    Pericytes are perivascular cells localized to capillaries that promote vessel maturation, and their absence can contribute to vessel loss. Whether impaired endothelial-pericyte interaction contributes to small vessel loss in pulmonary arterial hypertension (PAH) is unclear. Using 3G5-specific, immunoglobulin G-coated magnetic beads, we isolated pericytes from the lungs of healthy subjects and PAH patients, followed by lineage validation. PAH pericytes seeded with healthy pulmonary microvascular endothelial cells failed to associate with endothelial tubes, resulting in smaller vascular networks compared to those with healthy pericytes. After the demonstration of abnormal polarization toward endothelium via live-imaging and wound-healing studies, we screened PAH pericytes for abnormalities in the Wnt/planar cell polarity (PCP) pathway, which has been shown to regulate cell motility and polarity in the pulmonary vasculature. PAH pericytes had reduced expression of frizzled 7 (Fzd7) and cdc42, genes crucial for Wnt/PCP activation. With simultaneous knockdown of Fzd7 and cdc42 in healthy pericytes in vitro and in a murine model of angiogenesis, motility and polarization toward pulmonary microvascular endothelial cells were reduced, whereas with restoration of both genes in PAH pericytes, endothelial-pericyte association was improved, with larger vascular networks. These studies suggest that the motility and polarity of pericytes during pulmonary angiogenesis are regulated by Wnt/PCP activation, which can be targeted to prevent vessel loss in PAH.

    View details for DOI 10.1016/j.ajpath.2014.09.013

    View details for Web of Science ID 000346887200008

  • Hypoxia Inducible Factor-1 alpha Increases Bone Morphogenetic Protein Signaling In Pulmonary Artery Endothelial Cells Kuang, J., Tian, X., Tian, A., Semenza, G., Nicolls, M. R., Spiekerkoetter, E. AMER THORACIC SOC. 2015
  • Unique predictors of mortality in patients with pulmonary arterial hypertension associated with systemic sclerosis in the REVEAL registry. Chest Chung, L., Farber, H. W., Benza, R., Miller, D. P., Parsons, L., Hassoun, P. M., McGoon, M., Nicolls, M. R., Zamanian, R. T. 2014; 146 (6): 1494-1504

    Abstract

    Background:Patients with pulmonary arterial hypertension associated with systemic sclerosis (SSc-APAH) experience higher mortality rates than patients with idiopathic disease and those with other connective tissue diseases (CTD-APAH). We sought to identify unique predictors of mortality associated with SSc-APAH in the CTD-APAH population. Methods:The Registry to Evaluate Early and Long-Term PAH Management (REVEAL) is a multicenter, prospective US-based registry of patients with previously and newly diagnosed (enrollment within 90 days of diagnostic right heart catheterization) PAH. Cox regression models evaluated all previously identified candidate predictors of mortality in the overall REVEAL population to identify significant predictors of mortality in the SSc-APAH (n=500) versus non-SSc-CTD-APAH (n=304) populations. Results:Three-year survival in the previously diagnosed and newly diagnosed SSc-APAH group was 61.4±2.7% and 51.2±4.0%, respectively, compared with 80.9±2.7% and 76.4±4.6%, respectively, in the non-SSc-CTD-APAH group (P<.001). In multivariate analyses, males aged >60 years, systolic blood pressure (SBP) ≤110 mmHg, 6-minute walk distance (6MWD) <165 m, mean right atrial pressure (mRAP) >20 mmHg within 1 year, and pulmonary vascular resistance (PVR) >32 WU remained unique predictors of mortality in the SSc-APAH group; 6MWD ≥440 m was protective in the non-SSc-CTD-APAH group, but not the SSc-APAH group. Conclusions:Patients with SSc-APAH have higher mortality rates than non-SSc-CTD-APAH patients. Identifying SSc-APAH patients who are at particularly high risk of death, including elderly males and patients with low baseline SBP or 6MWD, or markedly elevated mRAP or PVR, will enable clinicians to identify patients who may benefit from closer monitoring and more aggressive treatment. Registered at:www.clinicaltrials.gov #NCT00370214.Patients with pulmonary arterial hypertension associated with systemic sclerosis (SSc-APAH) experience higher mortality rates than patients with idiopathic disease and those with other connective tissue diseases (CTD-APAH). We sought to identify unique predictors of mortality associated with SSc-APAH in the CTD-APAH population.The Registry to Evaluate Early and Long-Term PAH Management (REVEAL) is a multicenter, prospective US-based registry of patients with previously and newly diagnosed (enrollment within 90 days of diagnostic right heart catheterization) PAH. Cox regression models evaluated all previously identified candidate predictors of mortality in the overall REVEAL population to identify significant predictors of mortality in the SSc-APAH (n=500) versus non-SSc-CTD-APAH (n=304) populations.Three-year survival in the previously diagnosed and newly diagnosed SSc-APAH group was 61.4±2.7% and 51.2±4.0%, respectively, compared with 80.9±2.7% and 76.4±4.6%, respectively, in the non-SSc-CTD-APAH group (P<.001). In multivariate analyses, males aged >60 years, systolic blood pressure (SBP) ≤110 mmHg, 6-minute walk distance (6MWD) <165 m, mean right atrial pressure (mRAP) >20 mmHg within 1 year, and pulmonary vascular resistance (PVR) >32 WU remained unique predictors of mortality in the SSc-APAH group; 6MWD ≥440 m was protective in the non-SSc-CTD-APAH group, but not the SSc-APAH group.Patients with SSc-APAH have higher mortality rates than non-SSc-CTD-APAH patients. Identifying SSc-APAH patients who are at particularly high risk of death, including elderly males and patients with low baseline SBP or 6MWD, or markedly elevated mRAP or PVR, will enable clinicians to identify patients who may benefit from closer monitoring and more aggressive treatment.www.clinicaltrials.gov #NCT00370214.

    View details for DOI 10.1378/chest.13-3014

    View details for PubMedID 24992469

  • Impact of the lung allocation score on survival beyond 1 year. American journal of transplantation Maxwell, B. G., Levitt, J. E., Goldstein, B. A., Mooney, J. J., Nicolls, M. R., Zamora, M., Valentine, V., Weill, D., Dhillon, G. S. 2014; 14 (10): 2288-2294

    Abstract

    Implementation of the lung allocation score (LAS) in 2005 led to transplantation of older and sicker patients without altering 1-year survival. However, long-term survival has not been assessed and emphasizing the 1-year survival metric may actually sustain 1-year survival while not reflecting worsening longer-term survival. Therefore, we assessed overall and conditional 1-year survival; and the effect of crossing the 1-year threshold on hazard of death in three temporal cohorts: historical (1995-2000), pre-LAS (2001-2005) and post-LAS (2005-2010). One-year survival post-LAS remained similar to pre-LAS (83.1% vs. 82.1%) and better than historical controls (75%). Overall survival in the pre- and post-LAS cohorts was also similar. However, long-term survival among patients surviving beyond 1 year was worse than pre-LAS and similar to historical controls. Also, the hazard of death increased significantly in months 13 (1.44, 95% CI 1.10-1.87) and 14 (1.43, 95% CI 1.09-1.87) post-LAS but not in the other cohorts. While implementation of the LAS has not reduced overall survival, decreased survival among patients surviving beyond 1 year in the post-LAS cohort and the increased mortality occurring immediately after 1 year suggest a potential negative long-term effect of the LAS and an unintended consequence of increased emphasis on the 1-year survival metric.

    View details for DOI 10.1111/ajt.12903

    View details for PubMedID 25208599

  • Impact of the Lung Allocation Score on Survival Beyond 1 Year AMERICAN JOURNAL OF TRANSPLANTATION Maxwell, B. G., Levitt, J. E., Goldstein, B. A., Mooney, J. J., Nicolls, M. R., Zamora, M., Valentine, V., Weill, D., Dhillon, G. S. 2014; 14 (10): 2288-2294

    Abstract

    Implementation of the lung allocation score (LAS) in 2005 led to transplantation of older and sicker patients without altering 1-year survival. However, long-term survival has not been assessed and emphasizing the 1-year survival metric may actually sustain 1-year survival while not reflecting worsening longer-term survival. Therefore, we assessed overall and conditional 1-year survival; and the effect of crossing the 1-year threshold on hazard of death in three temporal cohorts: historical (1995-2000), pre-LAS (2001-2005) and post-LAS (2005-2010). One-year survival post-LAS remained similar to pre-LAS (83.1% vs. 82.1%) and better than historical controls (75%). Overall survival in the pre- and post-LAS cohorts was also similar. However, long-term survival among patients surviving beyond 1 year was worse than pre-LAS and similar to historical controls. Also, the hazard of death increased significantly in months 13 (1.44, 95% CI 1.10-1.87) and 14 (1.43, 95% CI 1.09-1.87) post-LAS but not in the other cohorts. While implementation of the LAS has not reduced overall survival, decreased survival among patients surviving beyond 1 year in the post-LAS cohort and the increased mortality occurring immediately after 1 year suggest a potential negative long-term effect of the LAS and an unintended consequence of increased emphasis on the 1-year survival metric.

    View details for DOI 10.1111/ajt.12903

    View details for Web of Science ID 000342663300014

  • CLOPIDOGREL PRESERVES MICROVASCULAR VASCULAR INTEGRITY IN ORTHOTOPIC TRACHEAL TRANSPLANTS AFFECTED BY OBLITERATIVE BRONCHIOLITIS Heim, C., Khan, M. A., Motsch, B., Mueller, S., Stamminger, T., Nicolls, M. R., Weyand, M., Ensminger, S. WILEY-BLACKWELL. 2014: 11
  • Nuclear Factor ?B Inhibition Reduces Lung Vascular Lumen Obliteration in Severe Pulmonary Hypertension in Rats. American journal of respiratory cell and molecular biology Farkas, D., Alhussaini, A. A., Kraskauskas, D., Kraskauskiene, V., Cool, C. D., Nicolls, M. R., Natarajan, R., Farkas, L. 2014; 51 (3): 413-425

    Abstract

    Nuclear factor-κB (NF-κB) and interleukin-6 (IL-6), a NF-κB downstream mediator, play a central role in the inflammatory response of tissues. We aimed to determine the role of the classical NF-κB pathway in severe pulmonary arterial hypertension (PAH) induced by SU5416 and chronic hypoxia (SuHx) in rats. Tissue samples from patients with idiopathic PAH (iPAH) and control subjects were investigated. SuHx rats were treated from days 1-3, 1-21 and 29-42 with the NF-κB inhibitor pyrrolidine dithiocarbamate (PDTC) and/or from days 1-21 with anti-IL-6 antibody. Nuclear staining for NF-κB, an indicator of the activation of the classical NF-κB pathway, was detected in pulmonary arterial lesions of iPAH patients and SuHx rats. NF-κB inhibition with PDTC prevented and reduced pulmonary arterial obliteration without reducing muscularization. However, the elevated lung levels of IL-6 were not reduced in PDTC-treated SuHx animals. PDTC treatment prevented or reduced apoptosis of pulmonary artery wall cells and pulmonary arterial obliteration. IL-6 inhibition had only a partial effect on apoptosis and obliteration. Pulmonary arterial media wall thickness was not affected by any of these treatments. Preventive and therapeutic PDTC treatment promoted immune regulation by increasing the number of perivascular CD4+ T cells, in particular regulatory T cells (early treatment) and by reducing the number of perivascular CD8+ T lymphocytes and CD45RA+ B lymphocytes. Therapeutic PDTC treatment further preserved right ventricular function in SuHx animals. Inhibition of NF-κB may represent a therapeutic option for pulmonary arterial obliteration via reduced vessel wall cell apoptosis and improved regulation of the immune system.

    View details for DOI 10.1165/rcmb.2013-0355OC

    View details for PubMedID 24684441

  • Graft microvascular disease in solid organ transplantation. Journal of molecular medicine (Berlin, Germany) Jiang, X., Sung, Y. K., Tian, W., Qian, J., Semenza, G. L., Nicolls, M. R. 2014; 92 (8): 797-810

    Abstract

    Alloimmune inflammation damages the microvasculature of solid organ transplants during acute rejection. Although immunosuppressive drugs diminish the inflammatory response, they do not directly promote vascular repair. Repetitive microvascular injury with insufficient regeneration results in prolonged tissue hypoxia and fibrotic remodeling. While clinical studies show that a loss of the microvascular circulation precedes and may act as an initiating factor for the development of chronic rejection, preclinical studies demonstrate that improved microvascular perfusion during acute rejection delays and attenuates tissue fibrosis. Therefore, preservation of a functional microvasculature may represent an effective therapeutic strategy for preventing chronic rejection. Here, we review recent advances in our understanding of the role of the microvasculature in the long-term survival of transplanted solid organs. We also highlight microvessel-centered therapeutic strategies for prolonging the survival of solid organ transplants.

    View details for DOI 10.1007/s00109-014-1173-y

    View details for PubMedID 24880953

  • Relaxin Increases Cellular Softening Which Synergizes With ECM-Softening LOX Inhibitor to Attenuates Airway Fibrosis in Mouse Orthotopic Tracheal Transplantation Lin, Y., Jiang, X., Nicolls, M. LIPPINCOTT WILLIAMS & WILKINS. 2014: 400
  • Clopidogrel Preserves Microvascular Integrity in Orthotopic Tracheal Transplants Affected By Obliterative Bronchiolitis. Heim, C., Khan, M., Motsch, B., Mueller, S., Stamminger, T., Nicolls, M., Weyand, M., Ensminger, S. LIPPINCOTT WILLIAMS & WILKINS. 2014: 327
  • Hypoxia Inducible Factor-1 alpha Limits Aspergillus fumigatus Invasion in the Rejecting Airway Allograft. Hsu, J., Jiang, X., Clemons, K., Stevens, D., Nicolls, M. LIPPINCOTT WILLIAMS & WILKINS. 2014: 270
  • Inflammation and Immunity in the Pathogenesis of Pulmonary Arterial Hypertension CIRCULATION RESEARCH Rabinovitch, M., Guignabert, C., Humbert, M., Nicolls, M. R. 2014; 115 (1): 165-175

    Abstract

    This review summarizes an expanding body of knowledge indicating that failure to resolve inflammation and altered immune processes underlie the development of pulmonary arterial hypertension. The chemokines and cytokines implicated in pulmonary arterial hypertension that could form a biomarker platform are discussed. Pre-clinical studies that provide the basis for dysregulated immunity in animal models of the disease are reviewed. In addition, we present therapies that target inflammatory/immune mechanisms that are currently enrolling patients, and discuss others in development. We show how genetic and metabolic abnormalities are inextricably linked to dysregulated immunity and adverse remodeling in the pulmonary arteries.

    View details for DOI 10.1161/CIRCRESAHA.113.301141

    View details for Web of Science ID 000337738900018

    View details for PubMedID 24951765

  • Clopidogrel Preserves Microvascular Integrity in Orthotopic Tracheal Transplants Affected By Obliterative Bronchiolitis Heim, C., Khan, M., Motsch, B., Mueller, S., Stamminger, T., Nicolls, M., Weyand, M., Ensminger, S. WILEY-BLACKWELL. 2014: 327
  • Hypoxia Inducible Factor-1 alpha Limits Aspergillus fumigatus Invasion in the Rejecting Airway Allograft. Hsu, J., Jiang, X., Clemons, K., Stevens, D., Nicolls, M. WILEY-BLACKWELL. 2014: 270
  • Relaxin Increases Cellular Softening Which Synergizes With ECM-Softening LOX Inhibitor to Attenuates Airway Fibrosis in Mouse Orthotopic Tracheal Transplantation Lin, Y., Jiang, X., Nicolls, M. WILEY-BLACKWELL. 2014: 400
  • Leukotrienes in pulmonary arterial hypertension. Immunologic research Tian, W., Jiang, X., Sung, Y. K., Qian, J., Yuan, K., Nicolls, M. R. 2014; 58 (2-3): 387-393

    Abstract

    Leukotrienes (LTs) are lipid mediators derived from the 5-lipoxygenase (5-LO) pathway of arachidonic acid metabolism and are markers and mediators of pulmonary inflammation. Research over the past two decades has established that LTs modulate inflammation in pulmonary arterial hypertension (PAH). The purpose of this review was to summarize the current knowledge of LTs in the pathophysiology of PAH and to highlight a recent study that advances our understanding of how leukotriene B4 (LTB4) specifically contributes to pulmonary vascular remodeling. The results of these studies suggest that pharmacological inhibition of LT pathways, especially LTB4, has high potential for the treatment of PAH.

    View details for DOI 10.1007/s12026-014-8492-5

    View details for PubMedID 24570092

  • Complement components as potential therapeutic targets for asthma treatment RESPIRATORY MEDICINE Khan, M. A., Nicolls, M. R., Surguladze, B., Saadoun, I. 2014; 108 (4): 543-549

    Abstract

    Asthma is the most common respiratory disorder, and is characterized by distal airway inflammation and hyperresponsiveness. This disease challenges human health because of its increasing prevalence, severity, morbidity, and the lack of a proper and complete cure. Asthma is characterized by TH2-skewed inflammation with elevated pulmonary levels of IL-4, IL-5, and IL-13 levels. Although there are early forays into targeting TH2 immunity, less-specific corticosteroid therapy remains the immunomodulator of choice. Innate immune injury mediated by complement components also act as potent mediators of the allergic inflammatory responses and offer a new and exciting possibility for asthma immunotherapy. The complement cascade consists of a number of plasma- and membrane-bound proteins, and the cleavage products of these proteins (C3 and C5) regulate the magnitude of adaptive immune responses. Complement protein are responsible for many pathophysiological features of asthma, including inflammatory cell infiltration, mucus secretion, increases in vascular permeability, and smooth muscle cell contraction. This review highlights the complement-mediated injury during asthma inflammation, and how blockade of active complement mediators may have therapeutic application.

    View details for DOI 10.1016/j.rmed.2014.01.005

    View details for Web of Science ID 000333856400001

    View details for PubMedID 24468195

  • Clopidogrel Preserves Microvascular Integrity in Orthotopic Tracheal Transplants affected by Obliterative Bronchiolitis Heim, C., Khan, M. A., Motsch, B., Mueller, S., Ramsperger-Gleixner, M., Stamminger, T., Nicolls, M. R., Weyand, M., Ensminger, S. ELSEVIER SCIENCE INC. 2014: S255
  • Efficacy of Transthoracic Echocardiography for Diagnosing Heart Failure in Septic Shock AMERICAN JOURNAL OF THE MEDICAL SCIENCES Beraud, A., Guillamet, C. V., Hammes, J. L., Meng, L., Nicolls, M. R., Hsu, J. L. 2014; 347 (4): 295-298

    Abstract

    Cardiac dysfunction occurs in up to 80% of patients with septic shock. Transthoracic echocardiography (TTE) is an ideal tool for the detailed characterization of cardiac function. Its feasibility is perceived to be poor in critically ill patients, but this has never been studied. To address this question, the authors evaluated the efficacy of TTE to diagnose heart failure in septic shock.This was a retrospective study. Patients admitted to the intensive care unit with septic shock and who had a TTE within 72 hours of intensive care unit admission were identified by a computer algorithm and validated by chart review. Echocardiography images were reviewed by a single cardiologist blinded to clinical outcomes. Clinical information was collected from patients' medical record.Seventy-six patients met the studies' inclusion criteria. The feasibility of TTE to calculate left ventricular ejection fraction was 90% and to assess diastolic function was 74%. Significant mitral regurgitation or aortic stenosis was the most frequent impediments for the assessment of diastolic function. Seventy-four percent of all patients showed some type of cardiac dysfunction (left or right ventricular systolic dysfunction and/or left ventricular diastolic dysfunction). In regression analyses, TTE feasibility was not impacted by factors previously associated with poor image acquisition: high body mass index, mechanical ventilation, tachycardia, advanced age or high severity of illness.This study demonstrated that TTE is a useful tool to assess myocardial function in critically ill patients and suggested its potential to assist in the management of patients with septic shock.

    View details for DOI 10.1097/MAJ.0b013e318297d616

    View details for Web of Science ID 000335788700008

    View details for PubMedID 24051955

  • Application of a non-amplification-based technology to detect invasive fungal pathogens DIAGNOSTIC MICROBIOLOGY AND INFECTIOUS DISEASE Hsu, J. L., Binkley, J., Clemons, K. V., Stevens, D. A., Nicolls, M. R., Holodniy, M. 2014; 78 (2): 137-140

    Abstract

    Current diagnostic techniques for fungal diseases could be improved with respect to sensitivity, specificity, and timeliness. To address this clinical need, we adapted a non-amplification-based nucleic acid detection technology to identify fungal pathogens. We demonstrate a high-specificity, detection sensitivity, reproducibility, and multiplex capacity for detecting fungal strains.

    View details for DOI 10.1016/j.diagmicrobio.2013.11.013

    View details for Web of Science ID 000330149700007

    View details for PubMedID 24359934

  • Working toward immune tolerance in lung transplantation. The Journal of clinical investigation Jiang, X., Nicolls, M. R. 2014: 1–4

    Abstract

    Long-term allograft survival is a major challenge facing solid organ transplantation. Recent studies have shown a negative correlation between infiltration of memory T cells and allograft survival. Furthermore, blockade of leukocyte activation increases acceptance of transplanted organs, including heart, liver, and kidney. Lung allografts are associated with high rates of rejection, and therapies that increase acceptance of other transplanted organs have not translated into the lung. In this issue of the JCI, Krupnick and colleagues demonstrate in a murine model that lung allograft acceptance requires infiltration of a specific T cell population into the graft. This study highlights the unique immunobiology of the lung and the complexity of lung transplant tolerance.

    View details for DOI 10.1172/JCI74701

    View details for PubMedID 24569371

  • Inhibition Of Nf-kappa b Improves Immune Regulation In The Su5416 And Chronic Hypoxia Model Of Severe Obliterative Pah Farkas, D., Kraskauskas, D., Kraskauskiene, V., Voelkel, N. F., Fowler, A. A., Natarajan, R., Nicolls, M. R., Farkas, L. AMER THORACIC SOC. 2014
  • Novel Risk Score Prediction Using Inflammatory Cytokines In Pulmonary Arterial Hypertension Selej, M., Tian, L., Scalfone, L., Lawrie, A., Nicolls, M. R., Robinson, W., Rabinovitch, M., Zamanian, R. T. AMER THORACIC SOC. 2014
  • Traumatic Brain Injury: Lungs in a RAGE. Science translational medicine Nicolls, M. R., Laubach, V. E. 2014; 6 (252): 252fs34

    Abstract

    Individuals who die of traumatic brain injury show damage to the lungs mediated by the HMGB1-RAGE axis, which renders the lungs suboptimal for transplantation (Weber et al.).

    View details for PubMedID 25186173

  • Macrophages in solid organ transplantation. Vascular cell Jiang, X., Tian, W., Sung, Y. K., Qian, J., Nicolls, M. R. 2014; 6 (1): 5-?

    Abstract

    Macrophages are highly plastic hematopoietic cells with diversified functions related to their anatomic location and differentiation states. A number of recent studies have examined the role of macrophages in solid organ transplantation. These studies show that macrophages can induce allograft injury but, conversely, can also promote tissue repair in ischemia-reperfusion injury and acute rejection. Therapeutic strategies that target macrophages to improve outcomes in solid organ transplant recipients are being examined in preclinical and clinical models. In this review, we discuss the role of macrophages in different types of injury and rejection, with a focus on macrophage-mediated tissue injury, specifically vascular injury, repair and remodeling. We also discuss emerging macrophage-centered therapeutic opportunities in solid organ transplantation.

    View details for DOI 10.1186/2045-824X-6-5

    View details for PubMedID 24612731

  • Promotion of airway anastomotic microvascular regeneration and alleviation of airway ischemia by deferoxamine nanoparticles. Biomaterials Jiang, X., Malkovskiy, A. V., Tian, W., Sung, Y. K., Sun, W., Hsu, J. L., Manickam, S., Wagh, D., Joubert, L., Semenza, G. L., Rajadas, J., Nicolls, M. R. 2014; 35 (2): 803-813

    Abstract

    Airway tissue ischemia and hypoxia in human lung transplantation is a consequence of the sacrifice of the bronchial circulation during the surgical procedure and is a major risk factor for the development of airway anastomotic complications. Augmented expression of hypoxia-inducible factor (HIF)-1α promotes microvascular repair and alleviates allograft ischemia and hypoxia. Deferoxamine mesylate (DFO) is an FDA-approved iron chelator which has been shown to upregulate cellular HIF-1α. Here, we developed a nanoparticle formulation of DFO that can be topically applied to airway transplants at the time of surgery. In a mouse orthotopic tracheal transplant (OTT) model, the DFO nanoparticle was highly effective in enhancing airway microvascular perfusion following transplantation through the production of the angiogenic factors, placental growth factor (PLGF) and stromal cell-derived factor (SDF)-1. The endothelial cells in DFO treated airways displayed higher levels of p-eNOS and Ki67, less apoptosis, and decreased production of perivascular reactive oxygen species (ROS) compared to vehicle-treated airways. In summary, a DFO formulation topically-applied at the time of surgery successfully augmented airway anastomotic microvascular regeneration and the repair of alloimmune-injured microvasculature. This approach may be an effective topical transplant-conditioning therapy for preventing airway complications following clinical lung transplantation.

    View details for DOI 10.1016/j.biomaterials.2013.09.092

    View details for PubMedID 24161166

  • The Critical Role of mRNA Destabilizing Protein Heterogeneous Nuclear Ribonucleoprotein D in 3 ' Untranslated Region-Mediated Decay of Low-Density Lipoprotein Receptor mRNA in Liver Tissue ARTERIOSCLEROSIS THROMBOSIS AND VASCULAR BIOLOGY Singh, A. B., Li, H., Kan, C. F., Dong, B., Nicolls, M. R., Liu, J. 2014; 34 (1): 8-?

    Abstract

    Previous studies showed that low-density lipoprotein receptor (LDLR) mRNA 3' untranslated region (UTR) contains regulatory elements responsible for rapid mRNA turnover in hepatic cells and mediates the mRNA stabilization induced by berberine (BBR). Here, we elucidate the underlying mechanism of BBR's action by characterizing mRNA-binding proteins that modulate LDLR mRNA decay via 3'UTR in liver tissue in vivo.We generated a transgenic mouse model (Alb-Luc-UTR) that expresses Luc-LDLR3'UTR reporter gene driven by the albumin promoter to study 3'UTR function in mediating LDLR mRNA decay in liver tissue. We show that treating Alb-Luc-UTR mice with BBR led to significant increases in hepatic bioluminescence signals, Luc-UTR mRNA, and LDLR mRNA levels as compared with control mice. These effects were accompanied by specific reductions of mRNA decay-promoting factor heterogeneous nuclear ribonucleoprotein D (hnRNP D) in liver of BBR-treated mice. Knockdown and overexpression studies further demonstrated that hnRNP D p37 isoform plays a major role in promoting hepatic LDLR mRNA degradation. In addition, we examined LDLR mRNA half-life, Luc-UTR reporter activity, and hnRNP D expression levels in cell lines derived from extrahepatic tissues. We demonstrated that strengths of 3'UTR in promoting mRNA degradation correlate with hnRNP D cellular abundances in nonhepatic cell lines, thereby suggesting its involvement in LDLR mRNA degradation beyond liver tissue.hnRNP D is critically involved in LDLR mRNA degradation in liver tissue in vivo. The inverse relationship of hnRNP D abundance with LDLR mRNA levels after BBR treatment suggests the potential of hnRNP D of being a novel therapeutic target for LDL cholesterol lowering.

    View details for DOI 10.1161/ATVBAHA.112.301131

    View details for Web of Science ID 000337731100005

    View details for PubMedID 24158514

  • Nf-?B Inhibition Prevents Vascular Obliteration and Improves Immune Regulation in Severe Pulmonary Arterial Hypertension Farkas, D., Alhussaini, A. A., Kraskauskas, D., Kraskauskiene, V., Nicolls, M. R., Voelkel, N. F., Natarajan, R., Farkas, L. LIPPINCOTT WILLIAMS & WILKINS. 2013