Autologous stem cell therapy in the treatment of limb ischaemia induced chronic tissue ulcers of diabetic foot patients.

BACKGROUND AND AIM Despite improvements in surgical revascularisation, limitations like anatomical factors or atherosclerosis limit the success of revascularisation in diabetic patients with critical limb ischaemia. Stem cells were shown to improve microcirculation in published studies. The aim of this study was to evaluate safety, feasibility and efficacy of transplantation of bone marrow derived cellular products regarding improvement in microcirculation and lowering of amputation rate. METHODS Bone marrow mononuclear cells (BMCs) in comparison with expanded bone marrow cells enriched in CD90+ cells ('tissue repair cells', TRCs) were used in the treatment of diabetic ulcers to induce revascularisation. Diabetic foot patients with critical limb ischaemia without option for surgical or interventional revascularisation were eligible. Parameters examined were ABI, TcPO(2) , reactive hyperaemia and angiographic imaging before and after therapy. RESULTS Of 30 patients included in this trial, 24 were randomised to receive either BMCs or TRCs. The high number of drop-outs in the control group (4 of 6) led to exclusion from evaluation. A total of 22 patients entered treatment; one patient in the TRC group and two in the BMC group did not show wound healing during follow up, one patient in each treatment group died before reaching the end of the study; one after having achieved wound healing (BMC group), the other one without having achieved wound healing (TRC group). Thus, 18 patients showed wound healing after 45 weeks. The total number of applicated cells was 3.8 times lower in the TRC group, but TRC patients received significantly higher amounts of CD90+ cells. Improvement in microvascularisation was detected in some, but not all patients by angiography, TcPO(2) improved significantly compared with baseline in both therapy groups. CONCLUSION The transplantation of BMCs as well as TRCs proved to be safe and feasible. Improvements of microcirculation and complete wound healing were observed in the transplant groups.