Mark R. Etherton, MD, PhD

Despite the advent of efficacious treatments for acute ischemic stroke, in the form of intravenous tPA and endovascular thrombectomy, post stroke disability is frequent. The prevalence of post stroke disability has served as the impetus for significant research into modalities to augment post stroke recovery. One promising approach is cellular therapy; including bone marrow derived mono-nuclear cells (BMMNCs), which have shown beneficial effects in animal models of ischemic stroke.

In this study, the authors conducted a systematic review of manuscripts using intravenous BMMNCs in animal models of ischemic stroke and performed a meta-analysis of histological and behavioral outcomes. They identified 22 studies in which the majority had assessments of common variables pertaining to infarct size and motor/functional outcomes.
While there was obvious heterogeneity among the individual studies with regards to methodologies and outcomes assessed. The pooled analysis was possible, in part, because the authors identified important shared approaches in the selection of specific animal models, timing of BMMNC injection, and outcome variables assessed (e.g. reduction in infarct size, cylinder test). BMMNC treated animals had significantly reduced infarct size (standardized mean difference -3.3, 95% CI: -4.3, -2.3) and enhanced performance on tests of sensorimotor function (cylinder test SMD -2.4, 95%CI: -3.1, -1.6).

This meta-analysis serves as an important summary of the pre-clinical data for one subtype of cellular therapy in ischemic stroke. BMMNCs have beneficial effects on infarct size and behavioral outcomes in animal models of ischemic stroke. Ideally, this study will serve as a platform on which future studies can build to target clinical trials for cellular therapies in human post stroke recovery.