Lung Recovery and Bioengineering Laboratory

Brandon A. Guenthart Lab

Brandon A. Guenthart, MD

Clinical Assistant Professor of Cardiothoracic Surgery

The Laboratory for Lung Recovery and Bioengineering is a collaborative research group working on expanding the pool of donor lungs and developing novel therapeutics to alleviate end-stage lung disease. Working to advance the field of ex vivo lung perfusion and advanced mechanical support, Dr. Guenthart and his colleagues have developed systems capable of prolonged normothermic organ support by harnessing the systemic regulation of the body. This radical advance allows for interventional therapies, functional recovery, cellular regeneration, and whole organ bioengineering.

With the bold vision to address the challenges and limitations in organ transplantation and regenerative medicine, the lab explores bioengineered solutions inspired by nature. Current work is focused on investigating cell-based therapeutics and extracellular matrix biomaterials in human ex vivo platforms and large animal models. Through this work, additional enabling technologies have been developed, including an airway cell replacement device, biomimetic lung sealant, and non-invasive lung imaging diagnostics. 

Publications

Publications

  • Pathological remodeling of distal lung matrix in end-stage cystic fibrosis patients. Journal of cystic fibrosis : official journal of the European Cystic Fibrosis Society Pinezich, M. R., Tamargo, M. A., Fleischer, S., Reimer, J. A., Hudock, M. R., Hozain, A. E., Kaslow, S. R., Tipograf, Y., Soni, R. K., Gavaudan, O. P., Guenthart, B. A., Marboe, C. C., Bacchetta, M., O'Neill, J. D., Dorrello, N. V., Vunjak-Novakovic, G. 2022

    Abstract

    Manifestations of cystic fibrosis, although well-characterized in the proximal airways, are understudied in the distal lung. Characterization of the cystic fibrosis lung 'matrisome' (matrix proteome) has not been previously described, and could help identify biomarkers and inform therapeutic strategies.We performed liquid chromatography-mass spectrometry, gene ontology analysis, and multi-modal imaging, including histology, immunofluorescence, and electron microscopy for a comprehensive evaluation of distal human lung extracellular matrix (matrix) structure and composition in end-stage cystic fibrosis.Quantitative proteomic profiling identified sixty-eight (68) matrix constituents with significantly altered expression in end-stage cystic fibrosis. Over 90% of significantly different matrix peptides detected, including structural and basement membrane proteins, were expressed at lower levels in cystic fibrosis. However, the total abundance of matrix in cystic fibrosis lungs was not significantly different from control lungs, suggesting that cystic fibrosis leads to loss of diversity among lung matrix proteins rather than an absolute loss of matrix. Visualization of distal lung matrix via immunofluorescence and electron microscopy revealed pathological remodeling of distal lung tissue architecture and loss of alveolar basement membrane, consistent with significantly altered pathways identified by gene ontology analysis.Dysregulation of matrix organization and aberrant wound healing pathways are associated with loss of matrix protein diversity and obliteration of distal lung tissue structure in end-stage cystic fibrosis. While many therapeutics aim to functionally restore defective cystic fibrosis transmembrane conductance regulator (CFTR), drugs that target dysregulated matrix pathways may serve as adjunct interventions to support lung recovery.

    View details for DOI 10.1016/j.jcf.2022.04.016

    View details for PubMedID 35525782

  • Imaging-Guided Bioreactor for Generating Bioengineered Airway Tissue. Journal of visualized experiments : JoVE Mir, S. M., Chen, J., Pinezich, M. R., O'Neill, J. D., Guenthart, B. A., Vunjak-Novakovic, G., Kim, J. 2022

    Abstract

    Repeated injury to airway tissue can impair lung function and cause chronic lung disease, such as chronic obstructive pulmonary disease. Advances in regenerative medicine and bioreactor technologies offer opportunities to produce lab-grown functional tissue and organ constructs that can be used to screen drugs, model disease, and engineer tissue replacements. Here, a miniaturized bioreactor coupled with an imaging modality that allows in situ visualization of the inner lumen of explanted rat trachea during in vitro tissue manipulation andculture is described. Using this bioreactor, the protocol demonstrates imaging-guided selective removal of endogenous cellular components while preserving the intrinsic biochemical features and ultrastructure of the airway tissue matrix. Furthermore, the delivery, uniform distribution, and subsequent prolonged culture of exogenous cells on the decellularized airway lumen with optical monitoring in situ are shown. The results highlight that the imaging-guided bioreactor can potentially be used to facilitate the generation of functional in vitro airway tissues.

    View details for DOI 10.3791/63544

    View details for PubMedID 35467661

  • Exvivo aortic valve replacement before orthotopic heart transplantation. JTCVS techniques Elde, S. F., Guenthart, B. A., Shudo, Y., Woo, Y. J. 2022; 12: 118-120

    View details for DOI 10.1016/j.xjtc.2022.01.008

    View details for PubMedID 35403016

  • Cannulation Strategies in Ex Vivo Lung Perfusion. ASAIO journal (American Society for Artificial Internal Organs : 1992) Guenthart, B. A., O'Neill, J. D., Bacchetta, M. 2021

    View details for DOI 10.1097/MAT.0000000000001621

    View details for PubMedID 34882646

  • Homogeneous Distribution of Exogenous Cells onto De-epithelialized Rat Trachea via Instillation of Cell-Loaded Hydrogel. ACS biomaterials science & engineering Chen, J., Mir, S. M., Pinezich, M. R., O'Neill, J. D., Guenthart, B. A., Bacchetta, M., Vunjak-Novakovic, G., Huang, S. X., Kim, J. 2021

    Abstract

    Injured or diseased airway epithelium due to repeated environmental insults or genetic mutations can lead to a functional decline of the lung and incurable lung diseases. Bioengineered airway tissue constructs can facilitate in vitro investigation of human lung diseases and accelerate the development of effective therapeutics. Here, we report robust tissue manipulation modalities that allow: (i) selective removal of the endogenous epithelium of in vitro cultured airway tissues and (ii) spatially uniform distribution and prolonged cultivation of exogenous cells that are implanted topically onto the denuded airway lumen. Results obtained highlight that our approach to airway tissue manipulation can facilitate controlled removal of the airway epithelium and subsequent homogeneous distribution of newly implanted cells. This study can contribute to the creation of innovative tissue engineering methodologies that can facilitate the treatment of lung diseases, such as cystic fibrosis, primary ciliary dyskinesia, and chronic obstructive pulmonary disease.

    View details for DOI 10.1021/acsbiomaterials.1c01031

    View details for PubMedID 34874712

  • Extended Static Hypothermic Preservation In Cardiac Transplantation: A Case Report. Transplantation proceedings Guenthart, B. A., Krishnan, A., Koyano, T., La Francessca, S., Chan, J., Alassar, A., Macarthur, J. W., Shudo, Y., Hiesinger, W., Woo, Y. J. 2021

    Abstract

    BACKGROUND: The donor shortage poses a major limitation to use of heart transplantation. Novel strategies such as use of expanded-criteria donors with prolonged ischemia times are being employed to address this need. Recent developments in static hypothermia have allowed for the safe use of cardiac allografts with prolonged ischemic times.CASE REPORT: We present the case of a 68-year-old woman with valvular cardiomyopathy refractory to medical therapy who underwent orthotopic heart transplantation with a cardiac allograft exposed to elevated ischemic times. This was achieved through use of the federally approved SherpaPak Cardiac Transport System for transportation of the allograft. This method of static hypothermic organ preservation allowed for a 330-minute total ischemic time, including 283 minutes of storage within the preservation system. The patient tolerated the procedure well and was discharged on postoperative day 10, with excellent graft function and no evidence of rejection 3 months postoperatively.CONCLUSIONS: Though traditionally ischemic times of 240 minutes or less are recommended for cardiac allografts, we demonstrate, to our knowledge, the longest reported ischemic time of 330 minutes via use of a novel method of static hypothermia for organ preservation. The recipient had an excellent outcome postoperatively, demonstrating the potential for this new organ preservation system to expand the donor pool and improve access and use of heart transplantation.

    View details for DOI 10.1016/j.transproceed.2021.08.021

    View details for PubMedID 34521542

  • Xenogeneic support for the recovery of human donor organs. The Journal of thoracic and cardiovascular surgery O'Neill, J. D., Guenthart, B. A., Hozain, A. E., Bacchetta, M. 2021

    Abstract

    VIDEO ABSTRACT.

    View details for DOI 10.1016/j.jtcvs.2021.07.055

    View details for PubMedID 34607726

  • Resection of a Giant Epithelioid Hemangioendothelioma Arising from the Superior Vena Cava. The Annals of thoracic surgery Elliott, I. A., Kasinpila, P., Guenthart, B. A., MacArthur, J. W., Berry, M. F. 2021

    Abstract

    Epithelioid hemangioendothelioma is a rare malignant vascular sarcoma. Here we present a patient with a very large tumor arising from the superior vena cava (SVC), in whom a resection with negative margins was accomplished using veno-venous bypass and bovine pericardial patch reconstruction of the SVC.

    View details for DOI 10.1016/j.athoracsur.2021.01.034

    View details for PubMedID 33529605

  • First lung and kidney multi-organ transplant following COVID-19 Infection. The Journal of heart and lung transplantation : the official publication of the International Society for Heart Transplantation Guenthart, B. A., Krishnan, A., Alassar, A., Madhok, J., Kakol, M., Miller, S., Cole, S. P., Rao, V. K., Acero, N. M., Hill, C. C., Cheung, C., Jackson, E. C., Feinstein, I., Tsai, A. H., Mooney, J. J., Pham, T., Elliott, I. A., Liou, D. Z., La Francesca, S., Shudo, Y., Hiesinger, W., MacArthur, J. W., Brar, N., Berry, G. J., McCarra, M. B., Desai, T. J., Dhillon, G. S., Woo, Y. J. 2021

    Abstract

    As the world responds to the global crisis of the COVID-19 pandemic an increasing number of patients are experiencing increased morbidity as a result of multi-organ involvement. Of these, a small proportion will progress to end-stage lung disease, become dialysis dependent, or both. Herein, we describe the first reported case of a successful combined lung and kidney transplantation in a patient with COVID-19. Lung transplantation, isolated or combined with other organs, is feasible and should be considered for select patients impacted by this deadly disease.

    View details for DOI 10.1016/j.healun.2021.02.015

    View details for PubMedID 34059432

  • Non-destructive vacuum-assisted measurement of lung elastic modulus. Acta biomaterialia Chen, J., Mir, S. M., Pinezich, M. R., O'Neill, J. D., Guenthart, B. A., Bacchetta, M., Vunjak-Novakovic, G., Huang, S. X., Kim, J. 2021

    Abstract

    In living tissues, mechanical stiffness and biological function are intrinsically linked. Alterations in the stiffness of tissues can induce pathological interactions that affect cellular activity and tissue function. Underlying connections between tissue stiffness and disease highlights the importance of accurate quantitative characterizations of soft tissue mechanics, which can improve our understanding of disease and inform therapeutic development. In particular, accurate measurement of lung mechanical properties has been especially challenging due to the anatomical and mechanobiological complexities of the lung. Discrepancies between measured mechanical properties of dissected lung tissue samples and intact lung tissues in vivo has limited the ability to accurately characterize integral lung mechanics. Here, we report a non-destructive vacuum-assisted method to evaluate mechanical properties of soft biomaterials, including intact tissues and hydrogels. Using this approach, we measured elastic moduli of rat lung tissue that varied depending on stress-strain distribution throughout the lung. We also observed that the elastic moduli of enzymatically disrupted lung parenchyma increased by at least 64%. The reported methodology enables assessment of the nonlinear viscoelastic characteristics of intact lungs under normal and abnormal (i.e., injured, diseased) conditions and allows measurement of mechanical properties of tissue-mimetic biomaterials for use in therapeutics or in vitro models. STATEMENT OF SIGNIFICANCE: Accurate quantification of tissue stiffness is critical for understanding mechanisms of disease and developing effective therapeutics. Current modalities to measure tissue stiffness are destructive and preclude accurate assessment of lung mechanical properties, as lung mechanics are determined by complex features of the intact lung. To address the need for alternative methods to assess lung mechanics, we report a non-destructive vacuum-based approach to quantify tissue stiffness. We applied this method to correlate lung tissue mechanics with tissue disruption, and to assess the stiffness of biomaterials. This method can be used to inform the development of tissue-mimetic materials for use in therapeutics and disease models, and could potentially be applied for in-situ evaluation of tissue stiffness as a diagnostic or prognostic tool.

    View details for DOI 10.1016/j.actbio.2021.06.037

    View details for PubMedID 34192570