Cell therapy for ischemic stroke

Stroke is the second, and in some countries the third cause of mortality in the population and one of the causes of disability in the adult population. According to statistics, in 2018, 15 million cases of stroke and 6 million deaths were diagnosed,The only currently approved treatments for acute stroke are intravenous tissue plasminogen activator (rtPA) and intra-arterial thrombectomy, which are used in less than 10% and 1% of patients, respectively.The literature review is devoted to the pathophysiology and molecular mechanisms of damage in cerebral ischemia. The modern concept of two strategies of cell therapy is discussed: neuroprotection and remodeling; the role of stem cells in reducing local and systemic inflammation, neurogenesis and angiogenesis, increasing neuronal plasticity, and protecting the blood-brain barrier, the role of paracrine factors and extracellular vesicles is shown.Methods of stem cell delivery are described: direct intracerebral transplantation, intraventricular and intrathecal, intravenous and intraarterial; the number of cells, their type and optimal delivery time depending on the acute, subacute and chronic periods of stroke. We also described recently designed the radially branched deployment (RBD) device and Cleveland multiport catheter for convection-enhanced delivery in which a cell-delivery catheter can be deployed at various angles and depths from a single longitudinal cannula. Finally, data on the completed 15 clinical trials from 2015 to the present, in which 513 patients took part, are presented. A detailed analysis of the efficacy and safety of cell therapy has been carried out.