CD8A and Cognitive impairment: Recently, one study showed that depletion of CD8+ T cells using a β2m-deficient mouse or impairing the accumulation or clonal expansion of CD8+ T cells by CCR6-deficiency increased Aβ deposition and cognitive impairment in 5XFAD mice by restraining the proinflammatory response of microglia (Su et al., 2023), which is in contrast with Fernando et al. (2023) study that also used β2m-deficient 5XFAD mice.