Efficacy of cell transplantation for ischemic stroke: A meta-analysis of randomized controlled trials.

Cell transplantation is a potential therapeutic strategy for ischemic stroke, but its clinical efficacy remains inconsistent. This meta-analysis evaluated functional outcomes at different follow-up time points, as well as neuroimaging and paracrine biomarkers. A systematic search of Embase, PubMed, Web of Science, and the Cochrane Library up to December 31, 2025 identified 21 randomized controlled trials involving 1,269 patients. The analysis showed that cell transplantation improved NIHSS at 6 and 12 months and final follow-up; mRS at 12 months and final follow-up; and BI at 3 and 6 months and final follow-up. Functional independence increased as measured by mRS scores at 0-1 and 0-2 at 12 months and by BI ≥90 or 95 at 3 and 12 months and final follow-up. MSCs improved NIHSS and BI, EPCs improved NIHSS and mRS, whereas MNCs showed no statistically significant effects. BBB-bypassing delivery demonstrated consistent efficacy. Transplantation within 10 days or after 90 days showed beneficial effects. Fugl-Meyer assessment scores and VEGF increased after cell transplantation, while infarct volume and DTI-FA showed no change. Cell transplantation induced functional benefits. Efficacy may depend on cell type, delivery strategy, and timing of transplantation, underscoring the critical influence of these variables on therapeutic outcomes.