Optogenetic engineered umbilical cord MSC-derived exosomes for remodeling of the immune microenvironment in diabetic wounds and the promotion of tissue repair

Abstract

Background Angiogenesis and tissue repair in chronic non-healing diabetic wounds remain critical clinical problems. Engineered MSC-derived exosomes have significant potential for the promotion of wound healing. Here, we discuss the effects and mechanisms of eNOS-rich umbilical cord MSC exosomes (UCMSC-exo/eNOS) modified by genetic engineering and optogenetic techniques on diabetic chronic wound repair. Methods Umbilical cord mesenchymal stem cells were engineered to express two recombinant proteins. Large amounts of eNOS were loaded into UCMSC-exo using the EXPLOR system under blue light irradiation. The effects of UCMSC-exo/eNOS on the biological functions of fibroblasts and vascular endothelial cells in vitro were evaluated. Full-thickness skin wounds were constructed on the backs of diabetic mice to assess the role of UCMSC-exo/eNOS in vascular neogenesis and the immune microenvironment, and to explore the related molecular mechanisms. Results eNOS was substantially enriched in UCMSCs-exo by endogenous cellular activities under blue light irradiation. UCMSC-exo/eNOS significantly improved the biological functions of cells after high-glucose treatment and reduced the expression of inflammatory factors and apoptosis induced by oxidative stress. In vivo, UCMSC-exo/eNOS significantly improved the rate of wound closure and enhanced vascular neogenesis and matrix remodeling in diabetic mice. UCMSC-exo/eNOS also improved the inflammatory profile at the wound site and modulated the associated immune microenvironment, thus significantly promoting tissue repair. Conclusion This study provides a novel therapeutic strategy based on engineered stem cell-derived exosomes for the promotion of angiogenesis and tissue repair in chronic diabetic wounds. Graphic Abstract

Stem Cell-Derived Extracellular Vesicles: Promising Therapeutic Opportunities for Diabetic Wound Healing

“… 88 Therefore, Zhao et al discovered that eNOS-loaded hUC-MSC-exos under blue light irradiation promoted tissue repair and reduced inflammatory cell infiltration and inflammation in diabetic wounds. 89 These EVs could promote diabetic wound tissue regeneration through activation of the PI3K/AKT/mTOR and FAK/ERK1/2 pathways and induction of autophagy.…”

Engineered Extracellular Vesicles in Wound Healing: Design, Paradigms, and Clinical Application

“…[104] Zhao et al constructed umbilical cord MSCs (UCMSCs) overexpressing CIBN-EGFP-CD9 and eNOS-mCherry-CRY2 to obtain eNOS-rich UCMSC-EV. [105] Under blue light irradiation, eNOS was spontaneously enriched in UCMSC-EV, and this process was realized by the EXPLOR (Blue Light Mediated Protein Interaction Technology) system. [105] 2) The second design direction for drug encapsulation in eEVs involves directly loading drugs into the EVs.…”

“…[105] Under blue light irradiation, eNOS was spontaneously enriched in UCMSC-EV, and this process was realized by the EXPLOR (Blue Light Mediated Protein Interaction Technology) system. [105] 2) The second design direction for drug encapsulation in eEVs involves directly loading drugs into the EVs. This approach often utilizes techniques such as electroporation, co-extrusion, and ultrasound due to their simplicity and high-loading efficiency.…”

“…[150] Interestingly, both calcein and PI-DNA can be excited by 490 nm, so that live and dead cells can be observed simultaneously by fluorescence microscopy. [105] The capacity for cell migration is another vital aspect investigated in wh-eEVs studies, involving methodologies such as scratch assays and transwell assays (Figure 6C). The scratch assay is a measure of various cells' migration ability, emulating the in vitro healing process.…”

Umbilical cord‐derived mesenchymal stem cell secretome promotes skin regeneration and rejuvenation: From mechanism to therapeutics

“…The endothelial NO synthase promotes diabetic wound healing, which can be spontaneously loaded into UCMSC‐exo by EXPLOR, a blue light‐mediated reversible protein–protein interaction approach. Finally, this kind of endothelial NO synthase‐loaded exosome has been shown to remodel the immune microenvironment, which is beneficial for tissue repair 120 …”