CD96 and HIV-1 infection: In detail, CD96 expression on NK cells was transiently and significantly upregulated in the first month after HIV-1 infection (Figure 2C, P = 0.013) but not in the third and twelfth month of infection, and then the significant CD96 upregulation on NK cells was exhibited in chronic infection over 2 years (Figure 2C, P = 0.012).