Bio

Professional Education


  • Master of Science, University College London (2012)
  • Bachelor of Science, University of Bristol (2011)
  • B of Medicine and B of Surgery, King's College School (2017)

Publications

All Publications


  • Embryonic skin development and repair. Organogenesis Hu, M. S., Borrelli, M. R., Hong, W. X., Malhotra, S., Cheung, A. T., Ransom, R. C., Rennert, R. C., Morrison, S. D., Lorenz, H. P., Longaker, M. T. 2018: 1–18

    Abstract

    Fetal cutaneous wounds have the unique ability to completely regenerate wounded skin and heal without scarring. However, adult cutaneous wounds heal via a fibroproliferative response which results in the formation of a scar. Understanding the mechanism(s) of scarless wound healing leads to enormous clinical potential in facilitating an environment conducive to scarless healing in adult cutaneous wounds. This article reviews the embryonic development of the skin and outlines the structural and functional differences in adult and fetal wound healing phenotypes. A review of current developments made towards applying this clinical knowledge to promote scarless healing in adult wounds is addressed.

    View details for DOI 10.1080/15476278.2017.1421882

    View details for PubMedID 29420124

  • An Improved Humanized Mouse Model for Excisional Wound Healing Using Double Transgenic Mice ADVANCES IN WOUND CARE Hu, M. S., Cheng, J., Borrelli, M. R., Leavitt, T., Walmsley, G. G., Zielins, E. R., Hong, W., Cheung, A. M., Duscher, D., Maan, Z. N., Irizarry, D. M., Stephan, B., Parsa, F., Wan, D. C., Gurtner, G. C., Lorenz, H., Longaker, M. T. 2018; 7 (1): 11–17

    Abstract

    Objective: Splinting full-thickness cutaneous wounds in mice has allowed for a humanized model of wound healing. Delineating the epithelial edge and assessing time to closure of these healing wounds via macroscopic visualization have remained a challenge. Approach: Double transgenic mice were created by crossbreeding K14-Cre and ROSAmT/mG reporter mice. Full-thickness excisional wounds were created in K14-Cre/ROSAmT/mG mice (n = 5) and imaged using both normal and fluorescent light on the day of surgery, and every other postoperative day (POD) until wound healing was complete. Ten blinded observers analyzed a series of images from a single representative healing wound, taken using normal or fluorescent light, to decide the POD when healing was complete. K14-Cre/ROSAmT/mG mice (n = 4) were subsequently sacrificed at the four potential days of rated wound closure to accurately determine the histological point of wound closure using microscopic fluorescence imaging. Results: Average time to wound closure was rated significantly longer in the wound series images taken using normal light, compared with fluorescent light (mean POD 13.6 vs. 11.6, *p = 0.008). Fluorescence imaging of histological samples indicated that reepithelialization was complete at 12 days postwounding. Innovation: We describe a novel technique, using double transgenic mice K14-Cre/ROSAmT/mG and fluorescence imaging, to more accurately determine the healing time of wounds in mice upon macroscopic evaluation. Conclusion: The accuracy by which wound healing can be macroscopically determined in vivo in mouse models of wound healing is significantly enhanced using K14-Cre/ROSAmT/mG double transgenic mice and fluorescence imaging.

    View details for DOI 10.1089/wound.2017.0772

    View details for Web of Science ID 000417829500001

    View details for PubMedID 29344430

    View details for PubMedCentralID PMC5770115

  • Pathway Analysis of Gene Expression of E14 Versus E18 Fetal Fibroblasts ADVANCES IN WOUND CARE Hu, M. S., Borrelli, M. R., Januszyk, M., Luan, A., Malhotra, S., Walmsley, G. G., Hong, W., Tevlin, R., Gurtner, G. C., Longaker, M. T., Lorenz, H. P. 2018; 7 (1): 1–10

    Abstract

    Objective: Fetuses early in gestation heal skin wounds without forming scars. The biological mechanisms behind this process are largely unknown. Fibroblasts, however, are cells known to be intimately involved in wound healing and scar formation. We examined fibroblasts in different stages of development to characterize differences in gene expression that may result in the switch from regenerative wound repair to repair with scarring. Approach: Fibroblasts were isolated and cultured from the back skin of BALB/c wild-type mouse fetuses at embryonic day (E)14 and E18 (n = 10). The fibroblast total RNA was extracted, and microarray analysis was conducted using chips containing 42,000 genes. Significance analysis of microarrays was performed to identify genes with greater than twofold expression difference and a false discovery rate of less than two. Identified genes subsequently underwent enrichment analysis to detect differentially expressed pathways. Results: Two hundred seventy-five genes were differentially expressed between E14 and E18 in fetal fibroblasts. Thirty genes were significantly downregulated and 245 genes were significantly upregulated at E18 compared with E14. Ingenuity pathway analysis identified the top 20 signaling pathways differentially activated in fetal fibroblasts between the E18 and E14 time points. Innovation: To our knowledge, this work represents the first instance where differentially expressed genes and signaling pathways between fetal fibroblasts at E14 and E18 have been studied. Conclusion: The genes and pathways identified here potentially underlie the mechanism behind the transition from fetal wound healing via regeneration to wound healing by repair, and may prove to be key targets for future therapeutics.

    View details for DOI 10.1089/wound.2017.0763

    View details for Web of Science ID 000417133000001

    View details for PubMedID 29344429

    View details for PubMedCentralID PMC5770085

  • Mesenchymal Stromal Cells and Cutaneous Wound Healing: A Comprehensive Review of the Background, Role, and Therapeutic Potential STEM CELLS INTERNATIONAL Hu, M. S., Borrelli, M. R., Lorenz, H., Longaker, M. T., Wan, D. C. 2018: 6901983

    Abstract

    Cutaneous wound repair is a highly coordinated cascade of cellular responses to injury which restores the epidermal integrity and its barrier functions. Even under optimal healing conditions, normal wound repair of adult human skin is imperfect and delayed healing and scarring are frequent occurrences. Dysregulated wound healing is a major concern for global healthcare, and, given the rise in diabetic and aging populations, this medicoeconomic disease burden will continue to rise. Therapies to reliably improve nonhealing wounds and reduce scarring are currently unavailable. Mesenchymal stromal cells (MSCs) have emerged as a powerful technique to improve skin wound healing. Their differentiation potential, ease of harvest, low immunogenicity, and integral role in native wound healing physiology make MSCs an attractive therapeutic remedy. MSCs promote cell migration, angiogenesis, epithelialization, and granulation tissue formation, which result in accelerated wound closure. MSCs encourage a regenerative, rather than fibrotic, wound healing microenvironment. Recent translational research efforts using modern bioengineering approaches have made progress in creating novel techniques for stromal cell delivery into healing wounds. This paper discusses experimental applications of various stromal cells to promote wound healing and discusses the novel methods used to increase MSC delivery and efficacy.

    View details for DOI 10.1155/2018/6901983

    View details for Web of Science ID 000434189400001

    View details for PubMedID 29887893

    View details for PubMedCentralID PMC5985130