Injectable decellularzied extracellular matrix hydrogel derived from human umbilical cord: A novel perspective to deal with refractory wound via medical wastes

Refractory wounds are frequent and protracted diabetes or postoperative complications that greatly affect the quality of life and mental health of patients. As a result of repeated dressing replacements and local debridement of the existing therapeutic therapies, freshly formed granulation is once more infiltrated by inflammation and eliminated, which delays the healing process. Herein, the improved Fryetes' method, which retained most of the active factors in the extracellular matrix, was developed to prepare injectable decellularized extracellular matrix hydrogels (dECMH) from human umbilical cord tissue. The physical, biochemical, in vivo and in vitro biological properties were analysed in detail. The results showed that the pre-gel exhibited good injectability and could form the hydrogel within 30 min. Biochemical analysis indicated that the prepared decellularized extracellular matrix retained abundant structural proteins and wound healing-related growth factors. In vitro and in vivo experiments confirmed the excellent biocompatibility of dECMH and the extremely high migration and proliferation capacities of human umbilical vein endothelial cells in the hydrogels. Thus, the injectability, gel-forming ability, and excellent biological characteristics of the hydrogel are highly compatible with refractory wounds with various irregular shapes, showing great potential for clinical application in wound repair.