Figure 3.

Examination of ovalbumin-specific T cell responses in mice injected with a mixture of ovalbumin and hsp70. Mice were injected twice as described in the legend of Fig. 1 with 120 pmol of recombinant ovalbumin, with 120 pmol of ova-hsp70 fusion protein, or with 120 pmol each of ovalbumin and hsp70. Ten days after the boost 5–10 spleens from each mouse group were pooled and processed. (A) IFN-γ secretion by splenocytes stimulated 72 h in vitro with 5 μg/ml recombinant ovalbumin protein (filled bars), SIINFEKL peptide (hatched bars), RGYVYQGL peptide (shaded bars), or tissue culture medium alone (empty bars). All samples were examined in triplicate. (B) Generation of ovalbumin-specific CTL by immunization with ova-hsp70 fusion protein in saline. Splenocyte cultures from mice immunized with recombinant ova □, ova-hsp70 fusion protein ▪, or a mixture of ovalbumin and hsp70 proteins ▵, were used as effector cells in a standard cytotoxicity assay. The following ⁵¹Cr-labeled target cells were used: E.G7-OVA (solid line) and EL4 cells alone (broken line).