Cytokine Profile of T-Cell Response

The production of T_H1 (IFNγ, TNFα, IL-2, MIP-1α, and MIP-1β) and T_H2 (IL-4 and IL-5) cytokines and IL-10 was evaluated after 20 h stimulation of T cells with S protein or human actin peptides. Briefly, PBMCs were stimulated for 20 h with SARS-CoV-2-specific peptide pools from S and a peptide pool of human actin (1 µg/mL) in the presence of co-stimulator molecules CD28 and CD49d (BD Bioscience). Cells were seeded in 96-wells round-bottom plates at a density of 0.5–1 × 10⁶ cells/200 µL culture medium per well. The concentrations of cytokines and chemokines were measured in duplicate in cell culture supernatants using BioPlex Pro Human Cytokine Screening Panel (27-Plex #M500KCAF0Y, Bio-Rad, Hercules, CA, USA) as previously described [3 (link)]. All the results were analysed with BIO-PLEX Manager software version 6.2 (Bio-Rad).