Background— Patients with severe limb ischemia may not be eligible for conventional therapeutic interventions. Pioneering clinical trials suggest that bone marrow–derived cell therapy enhances neovascularization, improves tissue perfusion, and prevents amputation. The objective of this trial was to determine whether repetitive intra-arterial infusion of bone marrow mononuclear cells (BMMNCs) in patients with severe, nonrevascularizable limb ischemia can prevent major amputation. Methods and Results— The Rejuvenating Endothelial Progenitor Cells via Transcutaneous Intra-arterial Supplementation (JUVENTAS) trial is a randomized, double-blind, placebo-controlled clinical trial in 160 patients with severe, nonrevascularizable limb ischemia. Patients were randomly assigned to repetitive (3 times; 3-week interval) intra-arterial infusion of BMMNC or placebo. No significant differences were observed for the primary outcome, ie, major amputation at 6 months, with major amputation rates of 19% in the BMMNC versus 13% in the placebo group (relative risk, 1.46; 95% confidence interval, 0.62–3.42). The safety outcome (all-cause mortality, occurrence of malignancy, or hospitalization due to infection) was not significantly different between the groups (relative risk, 1.46; 95% confidence interval, 0.63–3.38), neither was all-cause mortality at 6 months with 5% versus 6% (relative risk, 0.78; 95% confidence interval, 0.22–2.80). Secondary outcomes quality of life, rest pain, ankle-brachial index, and transcutaneous oxygen pressure improved during follow-up, but there were no significant differences between the groups. Conclusions— Repetitive intra-arterial infusion of autologous BMMNCs into the common femoral artery did not reduce major amputation rates in patients with severe, nonrevascularizable limb ischemia in comparison with placebo. The general improvement in secondary outcomes during follow-up in both the BMMNC and the placebo group, as well, underlines the essential role for placebo-controlled design of future trials. Clinical Trial Registration— URL: http://www.clinicaltrials.gov . Unique identifier: NCT00371371.

on behalf of the JUVENTAS and SMART study groups, Utrecht and Bilthoven, The Netherlands Objective: To provide a solid baseline reference for quality of life (QoL) in patients with no-option critical limb ischemia (CLI). CLI is associated with surgery, endovascular interventions, hospitalization, and a poor prognosis. An increasing number of clinical trials are, therefore, investigating new treatment strategies (eg, therapeutic neovascularization) in patients with CLI. QoL serves as an important secondary endpoint in many of these trials, but solid reference QoL data for patients with no-option CLI are lacking. Methods: The Medical Outcomes Study Short Form 36 (SF-36) and the EuroQol-5D (EQ-5D) questionnaires were used to obtain baseline QoL scores from 47 patients with no-option CLI participating in a therapeutic neovascularization trial. To allow for easy comparability, a norm-based scoring (NBS) method was used to report the results of the SF-36. Scores of patients with CLI were furthermore compared with scores of patients with milder forms of peripheral arterial disease (PAD) and with patients with cardiovascular risk factors only. Determinants of QoL in patients with PAD were identified using multiple linear regression methods. Results: Patients with no-option CLI reported QoL scores below the general population mean on every health dimensionof the SF-36. Physical functioning, role physical functioning, and bodily pain were affected most intensively. These poor physical QoL scores were further underlined when compared with other patients with milder forms of PAD or patients with cardiovascular risk factors only. Patients with CLI scored poorly on the pain/discomfort and the usual activities domain of the EQ-5D. Diabetes, female gender, body mass index, and the ankle-brachial index at rest were significant determinants of the QoL in PAD on multivariate analysis. Conclusion: The QoL data of patients with no-option CLI using NBS methods for the SF-36 provide a baseline reference for ongoing clinical trials on new treatment strategies. Our data stress the need for new revascularization therapies in patients with no-option CLI. ( J Vasc Surg 2010;52:843-9.)

This meta-analysis underlines the promising potential of BM-derived cell therapy in CLI patients. Importantly, the results of placebo-controlled and non-placebo-controlled RCTs seem to diverge, which stresses the necessity to use placebo in the control arms of these trials. Future well-designed larger placebo-controlled RCTs are needed and should include long-term follow-up data to assess durability of treatment effects.

BackgroundCritical limb ischemia (CLI) is characterized by lower extremity artery obstruction and a largely unexplained impaired ischemic neovascularization response. Bone marrow (BM) derived endothelial progenitor cells (EPC) contribute to neovascularization. We hypothesize that reduced levels and function of circulating progenitor cells and alterations in the BM contribute to impaired neovascularization in CLI.MethodsLevels of primitive (CD34+ and CD133+) progenitors and CD34+KDR+ EPC were analyzed using flow cytometry in blood and BM from 101 CLI patients in the JUVENTAS-trial (NCT00371371) and healthy controls. Blood levels of markers for endothelial injury (sE-selectin, sICAM-1, sVCAM-1, and thrombomodulin), and progenitor cell mobilizing and inflammatory factors were assessed by conventional and multiplex ELISA. BM levels and activity of the EPC mobilizing protease MMP-9 were assessed by ELISA and zymography. Circulating angiogenic cells (CAC) were cultured and their paracrine function was assessed.ResultsEndothelial injury markers were higher in CLI (P<0.01). CLI patients had higher levels of VEGF, SDF-1α, SCF, G-CSF (P<0.05) and of IL-6, IL-8 and IP-10 (P<0.05). Circulating EPC and BM CD34+ cells (P<0.05), lymphocytic expression of CXCR4 and CD26 in BM (P<0.05), and BM levels and activity of MMP-9 (P<0.01) were lower in CLI. Multivariate regression analysis showed an inverse association between IL-6 and BM CD34+ cell levels (P = 0.007). CAC from CLI patients had reduced paracrine function (P<0.0001).ConclusionCLI patients have reduced levels of circulating EPC, despite profound endothelial injury and an EPC mobilizing response. Moreover, CLI patients have lower BM CD34+-cell levels, which were inversely associated with the inflammatory marker IL-6, and lower BM MMP-9 levels and activity. The results of this study suggest that inflammation-induced BM exhaustion and a disturbed progenitor cell mobilization response due to reduced levels and activity of MMP-9 in the BM and alterations in the SDF-1α/CXCR4 interaction contribute to the attenuated neovascularization in CLI patients.

CLI patients with DM are at a significantly higher risk of major amputation than CLI patients without DM. This increased risk is associated with a higher prevalence of baseline ABI >1.4 and more severe ischemia at initial presentation in patients with DM.