Impact of implanted bone marrow progenitor cell composition on limb salvage after cell implantation in patients with critical limb ischemia.

OBJECTIVE

The aim of this study is to identify which factors influence limb salvage after bone marrow mononuclear cell implantation (BMI) in patients with chronic critical limb ischemia (CLI).

METHODS

Thirteen no-option CLI patients treated with BMI were enrolled in the present study. Limb ischemia was assessed using the ankle-brachial index (ABI), transcutaneous oxygen tension (TcO(2)), and rest pain score. The cell populations among the implanted cells were determined by May-Giemsa staining and flow cytometry.

RESULTS

Major lower extremity amputations after BMI were performed in seven patients. Before implantation, there were no significant differences between the amputation group (n=7) and the salvage group (n=6) in clinical characteristics, the ABI, the TcO(2) level, or the rest pain score. After implantation, there were no differences between the groups in the serum levels of angiogenic or inflammatory cytokines. The number of implanted BM cells was the same in the two groups, but the cells implanted in the limb salvage group were composed of significantly higher numbers of hematopoietic progenitors (erythroblasts and myeloblasts) and lymphocytes (p<0.05, respectively). The number of CD34-positive cells was somewhat greater in the salvage group than in the amputation group (p=0.09) and was positively associated with the number of erythroblasts (r(2)=0.29, p=0.06) and the number of myeloblasts (r(2)=0.59, p<0.01).

CONCLUSIONS

The cellular composition of the BM cells injected may affect limb salvage after the implantation in patients with severe CLI. The favorable effects of BMI appear to reflect the impact of the progenitor cell doses.