CD4 and brain infarction: It was found that CD8+ T-cells appeared as early as 3 h after cerebral infarction, whereas CD4+ T-cells appeared as early as 24 h after cerebral infarction, in which CD8+ T-cells may be related to neuronal death while CD4+ T-cells may play a role in tissue repair (Liesz and Kleinschnitz, 2016).