Figure 5.

PD-1 blockade restores bacteria-specific CD4 T cell proliferation in CVID patients. Blood mononuclear cells were labeled with CFSE and stimulated with bacteria- or virus-derived antigens in the presence or in the absence of α–PDL-1/2 Abs and proliferation was measured in CD4-positive T cells at day 6. (A) Representative flow cytometry profiles of bacteria-specific and virus-specific CD4 T cell proliferation in one representative CVID patient (CVID-02). Unstimulated cell cultures (negative control) and cell cultures stimulated with SEB (positive control) are also shown. (B and C) Percentage of bacteria-specific (B) or virus-specific (C) proliferating CD4 T cells in the presence or absence of α–PD-L1/2 Abs in CVID patients (n = 10). P-values were calculated using paired Student’s t test. *, P < 0.05.