Figure 2

Effects of HSP70, CMVpp65 _495-503 peptide, and HSP70/CMV-PC in the presence/absence of α2-macroglobulin on T-cell proliferation. PBMCs were labeled with CSFE and cultured with HSP70-peptide-binding buffer (NC), HSP70, CMVpp65_495-503 peptide, or HSP70/CMV-PC for 4 days. Cell proliferation within the CD8⁺ (A) and the A2/CMV-pentamer-positive CD8⁺ (B) T-cell populations was evaluated by CFSE dilution. In order to determine whether antiviral T-cell induction occurred due to cross-presentation of peptides by HSP70, the uptake of HSP70/CMV-PC was blocked by adding α2-macroglobulin (A2M). The results of 5 independent experiments using cells from medium responder are expressed as mean ± SD. Asterisks shown in the Figure indicate only statistically significant differences between levels in CMVpp65_495-503 peptide- and HSP70/CMV-PC-stimulated cells (* p < 0.05, ** p < 0.01, *** p < 0.001).