Figure 3.

T-cells proliferation is recovered by PD-L1/PD-1 axis blockage. PBMCs from healthy volunteers were labelled with CFSE, then cells were exposed or not (open circle) to S, N and P proteins for 5 days (solid black square). Anti-PD-L1 (solid black triangle) or anti-PD-1 (solid grey inverted triangle) were added. All cultures were also stimulated with Pokeweed (PWD, 2.5 μg/mL). Percentage of proliferative (CFSE^dim) CD4⁺ (A) and CD8⁺ (B) populations, measured by flow cytometry, are shown (∗, p < 0.05, paired t-test), n = 5. (C) An array analysis is shown for indicated cytokines, that were analyzed in the supernatant by Cytometric Bead Array (CBA) after stimulation with S, N and P proteins from SARS-CoV-2 (S + N + P) or not (control) of PBMCs from healthy volunteers for 5 days; n = 5.