Figure 4.

15d-PGJ₂ suppresses the collagen-induced Th17 immune response. ROR-γt mRNA expression was quantified by real-time PCR in draining lymph nodes from naïve mice (white bar) or collagen-immunized and challenged DBA/1 mice treated with vehicle (PBS) (black bar) or – 15d-PGJ₂ (1 mg/Kg) (hatched bar) for 7 days (a). ^# P < 0.05 when compared with naïve mice. ^∗ P < 0.05 when compared with vehicle (PBS). 15d-PGJ₂-pretreated nonadherent cells (2 × 10⁶ cells/mL) (1 hour before) from draining LNs from the mice above were stimulated in vitro with C-II (5 μg/mL) or plate-bound α-CD3 (5 μg/mL) for 96 h. Culture supernatants were harvested to measure IL-17 (b) levels from C-II- or α-CD3-stimulated cultures. The specific C-II (c) or αCD3 polyclonal (d) stimuli proliferation assay was assessed by overnight [³H]thymidine incorporation. The results are expressed as the mean ± SEM obtained from triplicate samples from two or three independent experiments (N = 3 per group). ^# P < 0.05 when compared with medium. ^∗ P < 0.05 compared with vehicle (PBS).