CD4 and sarcoidosis: Tfh cells (CD4+CXCR5+PD1+) in the peripheral blood of patients with active sarcoidosis were significantly higher as compared with patients with stable sarcoidosis (P = 0.041) and the healthy control group (P = 0.0061), while Tfh cells in patients with stable sarcoidosis were also higher when compared to the healthy control group (P = 0.0097; Figures 4B,E).