Novel Gene-Modified Mesenchymal Stem Cell Therapy Reverses Impaired Wound Healing in Ischemic Limbs.

Objective: Here, we report a new method to increase the therapeutic potential of mesenchymal stem/stromal cells (MSCs) for ischemic wound healing. We tested biological effects of MSCs modified with E-selectin, a cell adhesion molecule capable of inducing postnatal neovascularization, on a translational murine model.
Background: Tissue loss significantly worsens the risk of extremity amputation for patients with chronic limb-threatening ischemia. MSC-based therapeutics hold major promise for wound healing and therapeutic angiogenesis, but unmodified MSCs demonstrate only modest benefits.
Methods: Bone marrow cells harvested from FVB/ROSA26Sor mTmG donor mice were transduced with E-selectin-green fluorescent protein (GFP)/AAV-DJ or GFP/AAV-DJ (control). Ischemic wounds were created via a 4 mm punch biopsy in the ipsilateral limb after femoral artery ligation in recipient FVB mice and subsequently injected with phosphate-buffered saline or 1×10 6 donor MSC GFP or MSC E-selectin-GFP . Wound closure was monitored daily for 7 postoperative days, and tissues were harvested for molecular and histologic analysis and immunofluorescence. Whole-body DiI perfusion and confocal microscopy were utilized to evaluate wound angiogenesis.
Results: Unmodified MSCs do not express E-selectin, and MSC E-selectin-GFP gain stronger MSC phenotype yet maintain trilineage differentiation and colony-forming capability. MSC E-selectin-GFP therapy accelerates wound healing compared with MSC GFP and phosphate-buffered saline treatment. Engrafted MSC E-selectin-GFP manifest stronger survival and viability in wounds at postoperative day 7. Ischemic wounds treated with MSC E-selectin-GFP exhibit more abundant collagen deposition and enhanced angiogenic response.
Conclusions: We establish a novel method to potentiate regenerative and proangiogenic capability of MSCs by modification with E-selectin/adeno-associated virus. This innovative therapy carries the potential as a platform worthy of future clinical studies.
Competing Interests: The E-selectin gene modification technologies described in referenced articles by Z.J.L. and O.C.V. were developed in our research laboratory and patented/licensed by the University of Miami. This technology is currently under preclinical development by Ambulero Inc., a new start-up company out of the University of Miami that focuses on developing new vascular treatments for ischemic conditions. Z.J.L. and O.C.V. are coinventors, serve as consultants and scientific and medical advisory officers in Ambulero Inc. and are Ambulero Inc. minority shareholders. The remaining authors report no conflicts of interest.
(Copyright © 2023 The Author(s). Published by Wolters Kluwer Health, Inc.)