After the onset of ischemic stroke, upon activation, γδ T cells can release IL-17a, IL-21, IL-22, and IFN-γ, and then participated in the pathogenic process, including secretion of pro-inflammatory factors, breakdown of the integrity of BBB, and recruitment of inflammatory cells into the affected tissues, and eventually cause irreversible brain injury. The gene discussed is IFNG; the disease is ischemic stroke.