FIGURE 1.

PBMCs were stimulated in vitro with medium (RPMI plus 5% human AB serum) or with SARS‐CoV‐2 S, N, and M proteins peptide pool (Miltenyi Biotech) for 6 h. Then CD3⁺CD4⁺ T cells were evaluated by flow cytometry for CD154 expression and IFN‐γ and IL‐2 intracellular production