PDCD1 and Kaposi's sarcoma: Regarding CD57+ NKThigh cells, the MFI of PD-1 was higher in KS/HIV than in HIV+ asymptomatic men [CT, p = 0.0021; MT, p = 0.0010]; and CT increased the PD-1 expression on CD57+ NKThigh cells at W4 compared to W0 (p = 0.0287) (Figure 9E).