Granulocyte colony-stimulating factor (GCSF) is currently used to treat neutropenia due to chemotherapy and has been successfully used for patients who require bone marrow transplants. The study is the first to report on the neuroprotective effect of GCSF in vivo and showed that it improved neurological deficits that occur in the first few days following cerebral ischemia. GCSF improved long-term behavioral outcomes while also stimulating a neural progenitor recovery response in a mouse model.