Stroke is a leading cause of death and disability, affecting 1 in 4 people during their lifetime. Stroke happens when blood vessels in the brain get clogged or damaged, impairing blood flow and oxygen supply to the brain, which leads to death of neurons and other brain cells. Although brain damage can be limited by interventions to restore blood flow, most stroke survivors experience some lifelong impairments of e.g. speech, movement, or cognitive function.  

Despite the existence of immature stem cells in the brain, their role in repair is uncertain and the brain’s ability to recover from stroke remains limited. Takakuni Maki, Ken Yasuda, Kazuto Tsukita, and colleagues from Kyoto University, Japan, have now demonstrated that oligodendrocyte progenitor cells (OPCs)—a well-known immature glial cell type in the brain—can promote new blood vessel formation after stroke under hypoxic conditions. The research was published today in Stem Cell Reports.