Figure 5.

Stimulation of naïve T cells. CD4⁺CD25⁻ naïve T cells were purified from 2-3 month old mice (for details see Materials and Methods). Cells were cultured alone (w/o) or in the presence of plated-bound anti-CD3 antibody (aCD3) (A) or PHA (B) at different concentrations. Cell proliferation was determined by thymidine incorporation after 3 days of stimulation (³H thymidine added for the last 16hours). C) Serum IL-2 levels were determined in the culture supernatants after stimulation with plated-bound anti-CD3 Ab (1μg/ml) using ELISA. Shown are data (mean ± SD) representative of 3 independent experiments. The data were analysed by two-tailed Student’s t-test. The genotypes of the mice are shown.