FIG. 1.

rIL-21-IgFc treatment temporarily reduces T cell activation. (A–D) Longitudinal representation of the frequency of CD38⁺HLA-DR⁺ cells among total, naive, central memory, and effector memory CD4⁺ T cells. (E) Positive trend between plasma viremia and the CD38⁺HLA-DR⁺ phenotype among effector memory CD4⁺ T cells. (F) Frequency of CD38⁺HLA-DR⁺ cells among total CD4⁺ T cells under conditions of no stimulation (Control), PMA/ionomycin stimulation (PMA/iono), and PMA/ionomycin stimulation +10 ng/ml rIL-21-IgFc (PMA/ionomycin + IL-21-IgFc). (G) Frequency of CD38⁺HLA-DR⁺ cells among naive, central memory, and effector memory CD4⁺ T cells under conditions of no stimulation, PMA/ionomycin stimulation, or PMA/ionomycin with 10 ng/ml rIL-21-IgFc. PMA, phorbol 12-myristate 13-acetate.