Within 24 hours of onset, the stroke patients showed elevated levels of sCD137 (2.7 pg/ml) and CD137 expression on CD4+ T cells (4.9 ± 3.2%) compared with normal controls (1.1 pg/ml, P < 0.01; 1.3 ± 1.0%, P < 0.01). The gene discussed is CD4; the disease is Stroke.