Figure 4.
Increased numbers of IFN-γ–secreting (A) CD8+ and (B) CD4+ T cells in the peritoneum of LCMV-immune mice challenged with VV (Day 3). Peritoneal cells were harvested from age-matched naive and LCMV-immune C57BL/6 mice challenged with purified VV at day 3 of infection or from LCMV-immune mice challenged with control purified cell supernatant (day 3). The total number of CD8+ and CD4+ cells (cross-hatched bars) and total number of IFN-γ secreting CD8+ and CD4+ cells (solid bars) was determined as described in Materials and Methods. *Represents a statistically significant difference from the LCMV-immune+VV group (P < 0.01).