Fig. 4.

PSA-dependent GSK3β inhibition promotes CREB-mediated transcription. (A) Western blot analysis of phospho-GSK3β in macrophages stimulated with PSA and Pam₃CSK₄. (B) CD4⁺ T cells cocultured with splenic DCs for 5 d in the presence of anti-CD3 and GSK3β inhibitor SB216763. Cocultures were either treated or not treated with PSA (50 μg/mL), and IL-10 was measured by ELISA of culture supernatants. These data are representative of 2 independent experiments. (C) Real-time PCR analysis of PSA-stimulated DCs with and without CREB inhibitors for transcript levels of costimulatory molecules. These data areaverage of 2 independent experiments. (D) IL-10 secretion from CD4⁺ T cells cocultured with splenic DCs in response to PSA in the presence of CREB inhibitor 666-15. These data are representative of 2 independent experiments. In B–D, error bars indicate SD. ND, not detected.