Therapeutic Efficacy of Mesenchymal Stem Cell-Derived Extracellular Vesicles for Critical Limb Ischemia: A Preclinical Systematic Review and Meta-Analysis with Source-Specific Subgroup Analysis.

Background

Critical limb ischemia (CLI), the most advanced stage of peripheral arterial disease, is associated with substantial risks of limb loss and mortality. As many patients are ineligible for revascularization, novel regenerative therapies are needed. Mesenchymal stem cell-derived extracellular vesicles (MSC-EVs) have emerged as promising cell-free therapeutics due to their pro-angiogenic, anti-inflammatory, and tissue-repair properties.

Objective

To systematically evaluate and quantitatively synthesize preclinical evidence regarding the efficacy of MSC-EVs in animal models of critical limb ischemia or hindlimb ischemia.

Methods

This systematic review and meta-analysis was conducted in accordance with PRISMA 2020 guidelines and registered in PROSPERO. PubMed, ScienceDirect, and Europe PMC were searched from inception to March 2026 for in vivo preclinical studies investigating MSC-EV therapy in CLI or hindlimb ischemia models. Random-effects meta-analysis was performed using Hedges' g. Subgroup analyses were conducted according to MSC source.

Results

Thirteen studies met the inclusion criteria for qualitative synthesis, and seven studies provided sufficient quantitative data and were included in the meta-analysis. Pooled analysis demonstrated a large and significant improvement in perfusion recovery following MSC-EV therapy compared with controls (Hedges' g = 4.02, 95% CI 3.03-5.01; p < 0.00001). No statistical heterogeneity was observed (I2 = 0%). Subgroup analyses showed consistent therapeutic benefits across adipose-derived MSC-EVs (g = 4.46, 95% CI 2.81-6.12), bone marrow-derived MSC-EVs (g = 3.71, 95% CI 2.10-5.31), and umbilical cord-derived MSC-EVs (g = 3.87, 95% CI 1.92-5.82), with no significant differences between sources (p = 0.80).

Conclusions

MSC-EVs significantly enhance perfusion recovery in preclinical CLI models, with comparable efficacy across different MSC sources. These findings support the translational potential of MSC-EVs as a regenerative therapy for CLI and justify further investigation in rigorously designed clinical trials.