Bioactive self-healing umbilical cord blood exosomes hydrogel for promoting chronic diabetic wound healing.

The deleterious effects of diabetes mellitus on wound healing have become a major public health concern worldwide. Given the complex microenvironment of diabetic wounds and the high prevalence of diabetes, the design and development of novel wound dressing materials with versatile capabilities is urgent. Extracellular vesicles (EVs) derived from human umbilical cord blood have demonstrated the potential to counter inflammation and accelerate wound healing. Herein, we explored the efficacy of incorporating human umbilical cord blood-derived exosomes (UCB-Exos) into an ABA-type amphiphilic hydrogel, which possesses the attributes of exosome (Exo) encapsulation, temperature-triggered reversible sol-gel conversion, and Exo-regulated release, for enhancing the stability and retention of Exos. We sought to examine the feasibility of this strategy in augmenting the therapeutic efficacy of UCB-Exos for the healing of diabetes-related wounds. The injectable hydrogel was conveniently applied directly onto the wound surface and the enclosed Exo significantly facilitated the healing process, resulting in faster wound closure, enhanced collagen deposition, accelerated re-epithelialization, and enhanced neo-vascularization within two weeks compared with the hydrogel-only treatment group. In summary, some hydrogels hold great promise for promoting wound healing in diabetics and represent a novel therapeutic option for diabetes-related ulcers.