Engineered skin graft with stromal vascular fraction cells encapsulated in fibrin–collagen hydrogel: A clinical study for diabetic wound healing

Despite the abundance of skin substitutes in the worldwide market, major hurdles in developing more complex tissues include the addition of skin appendages and vascular networks as the most important structure. The aim of this research was a clinical feasibility study of a novel prevascularized skin grafts containing the dermal and epidermal layer using the adipose stromal vascular fraction (SVF)-derived endothelial cell population for vascular network regeneration. Herein, we characterized hydrogel with emphasis on biological compatibility and cell proliferation, migration, and vitality. The therapeutic potential of the prevascularized hydrogel transplanted on five human subjects as an intervention group with diabetic wounds was compared with nonvascularized skin grafts as the control on five patients. Wound planimetric and biometric analysis was performed using a Mann-Whitney nonparametric t-test (p ≤ .05). The fibrin-collagen hydrogel was suitable for skin organotypic cell culture. There was a significant (p ≤ .05) increased in skin thickness and density in the vascular beds of the hypodermis measured with skin scanner compared with that in the control group. No significant macroscopic differences were observed between the intervention and control groups (p ≤ .05). In summary, we report for the first time the use of autologous dermal-epidermal skin grafts with intrinsic vascular plexus in a clinical feasibility study. The preliminary data showed that SVF-based full-thickness skin grafts are safe and accelerate the wound healing process. The next stage of the study is a full-scale randomized clinical trial for the treatment of patients with chronic wounds.