Fig. 5.

IL-17 induces class switching in vitro. B cells were purified and activated in the presence of increasing doses of the indicated cytokines. Antibody production and class switch recombination were analyzed in response to stimulation with anti-CD40 (5 μg/mL)/IgM (5 μg/mL) plus IL-17 (0.1/1/10 ng/mL) or IL-21 (10/25/50 ng/mL) or no cytokine as a control. Columns for each cytokine represent increasing concentrations from left to right. Graphs show mean concentration (in nanograms per milliliter) ± SEM, representing 10 cultures per condition. *P < 0.05; **P < 0.01, IL-17 or IL-21 vs. no cytokine.