Assessment of the Efficacy and Tolerance of Sub-cutaneous Re-injection of Autologous Adipose-derived REGEnerative Cells in the Local Treatment of Neuropathic Diabetic Foot ulcERs

Diabetic foot ulcer (DFU) is a major complication and the leading cause of hospitalization among people with diabetes mellitus. It occurs in 15% of all patients with diabetes and precedes 84% of all lower leg amputations. Despite many therapeutic advances over the past decades, including dressings (hydrocolloids, alginate, skin substitutes) and growth factors, healing rates of DFU remain low.

Mechanisms of faulty wound healing in diabetic patients are complex, related to both intrinsic and extrinsic factors. The main reasons for impaired healing appears to be: 1/exhaustion of local cell populations that promote wound healing; 2/excessive production of matrix metalloproteases (MMPs) coupled with reduced expression of the tissue inhibitors of MMPs; 3/impaired neovascularisation coupled with reduced numbers of endothelial progenitor cells and impairment of their functioning. These imbalances may result in excessive degradation of extracellular matrix components, as well as an inappropriate local inflammatory response .

Adipose-derived stroma vascular fraction provides a rich and easily accessible source of autologous cells for regenerative medicine applications. Il contains multipotent stem cells and progenitors called adipose-derived regenerative cells (ADRCs) able to stimulate wound healing. There are attracted to the wound site where they supplement the wound bed with similar cell types, secrete numerous growth factors and cytokines, increase macrophage recruitment, enhance granulation tissue, and improve vascularisation . The reparative capabilities coupled with good safety of ADRCs have been illustrated in a study for treating severe and irreversible radiation-induced lesions, and in a study for treating sclerodactyly in patients with diffuse scleroderma. Numerous case reports showing healing of refractory wounds following treatment with autologous ADRCs have also been reported.

Based on these previous reports, the present study aims to assess the efficacy and tolerance of injection of ADRCs for the local treatment of neuropathic or neuro-ischemic DFU.