Compared to sham mice, mice subjected to ileocecal resection showed an obvious increase in the number of CD44hiCD62LloCD8+ T effector lymphocytes in peripheral and ischemic brain tissues at Day 7 after ischemic stroke, whereas the number of brain-infiltrating CD4+ T lymphocytes and neutrophils was not significantly different. The gene discussed is CD4; the disease is ischemic stroke.