Figure 2. Functional inactivation of CD25⁺ cells significantly increases the magnitude of the TMEV-specific CD8⁺ T cell response in TMEV-infected SJL/J, but not C57BL/6 mice.

Groups of 4–5 SJL/J mice were treated with control Ig or 500 μg of anti-CD25 mAb (clone PC-61) i.p. on days -2 and 0 relative to i.c. infection with 5×10⁶ pfu/mouse of TMEV on day 0. At 7 days (A) and 26 days (C) PI, splenic IFN-γ ELISPOT responses to the to the immunodominant (VP3₁₅₉) and subdominant (VP3₁₇₃ and VP1₁₁) SJL TMEV epitopes were assessed. In vivo lysis responses were also assessed on day 7 PI (B) to VP3₁₅₉- and VP3₁₇₃-pulsed targets and on day 26 PI (D) to VP3₁₅₉-pulsed targets. C57BL/6 mice were also treated with control Ig or 500 μg of PC-61 i.p. on days -2 and 0 relative to TMEV infection and IFN-γ ELISPOT responses to the immunodominant (VP2₁₂₁) and subdominant (VP2₁₆₅ and VP3₁₁₀) B6 epitopes (E) as well as in vivo lysis responses to VP3₁₂₁-pulsed targets (F) were determined 7 days PI. The indicated ELISPOT and in vivo lytic responses in SJL mice were significantly enhanced in PC-61 treated mice (*p<0.05; **p<0.01). Data represent 2–3 individual experiments carried out at similar time points. Error bars are representative of the standard deviation within a sample group.