Figure 8.

(a) Generation of B cells with “protective” phenotype is controlled by endogenous IL-10. Splenocytes isolated from DBA/1-TcR-β-Tg were cultured with CII/isotype control, or CII/anti-CD40 for 48 h alone or in the presence of neutralizing anti–IL-10R mAb (1B1.2) or anti–IL-4 mAb (11B11). 5 × 10⁵ B cells were purified and transferred intraperitoneally to DBA/1-TcR-β-Tg mice at the time of CII/CFA immunization. Data are representative of two experiments. Groups of mice were compared by statistical analysis using the Fisher exact test. (b) Antigen-specific CD4⁺ T cells also play a crucial role in the generation of B cells with “protective” phenotype. CD4⁺ T cells were depleted by positive selection from splenocytes isolated from arthritic DBA/1-TcR-β Tg mice. Undepleted or depleted splenocytes were stimulated with CII/isotype control, CII/anti-CD40. After 48 h incubation, 5 × 10⁶ nondepleted or depleted cells were transferred intraperitoneally, at the time of CII/CFA immunization, to DBA/1-TcR-β Tg mice. Incidence of arthritis. Mice groups were compared by statistical analysis using the Fisher exact test. Data are representative of three experiments.