Figure 2
S protein-specific T cell immune responses in young and older subjects. PBMCs from HCoVs high-responders, 5 young (red dot) and 5 older (black dot) adults, were cultured in the presence of NL63 and OC43 inactivated virus (inact. virus; 2.5 µg/ml) recombinant spike proteins (rec. Spike; 2.5 µg/ml) or peptide pools (S1 and S2; 0.4 µg/ml each peptide) and frequency of IFN-γ producing T cells measured by ELISpot. Data were background-subtracted and expressed as SFC/106 PBMCs. Each dot represents a single subject. Statistical comparison between the two groups was performed using non-parametric Mann–Whitney test for unpaired samples (**p = 0.0079; *p < 0.05; ns: not significant).
