Table 1.

Cytokine production by CD4 and CD8 T cells after polyclonal and antigen-specific stimulationa

Mouse genotypeDays after LCMVValue after polyclonal activationValue after antigen-specific activation for CD8 T cells
CD4 T cellsCD8 T cells
% IL-2+% IFN-γ+% IL-2+% IFN-γ+% IFN-γ+MFI over backgroundb
B+/+83.3 ± 0.19.6 ± 0.63.1 ± 0.845 ± 162 ± 1120.3 ± 8.3
B−/−83.2 ± 0.46.5 ± 0.83.3 ± 0.132 ± 673 ± 521.3 ± 6.5
B+/+303.0 ± 0.56.4 ± 1.97.0 ± 1.248 ± 176 ± 847.3 ± 1.9
B−/−301.6 ± 0.22.8 ± 0.31.4 ± 0.441 ± 174 ± 630.3 ± 2.8
B+/+602.8 ± 0.32.6 ± 0.36.8 ± 1.032 ± 382 ± 357.1 ± 10.9
B−/−603.1 ± 0.42.0 ± 1.02.6 ± 1.036 ± 778 ± 727.1 ± 6.9
  • a Splenocytes were polyclonally or antigen specifically activated as described in Materials and Methods. At 30 and 60 days after LCMV infection, more B+/+ CD8 T cells but not CD4 T cells produced IL-2 (P < 0.04). More B+/+ CD4 and CD8 T cells produced IFN-γ 8 and 30 days after infection. At all time points, equal numbers of CD8 T cells in B+/+ and B−/− mice produced IFN-γ after antigen-specific stimulation. However, 30 and 60 days after infection, CD8 T cells from B−/− mice produced less IFN-γ, as determined by mean fluorescence intensity. Three mice per group were tested in two to three independent experiments.

  • b MFI over background, geometric mean of fluorescence intensity of cytokine-positive cells divided by the geometric mean of fluorescence intensity of cytokine-negative cells.