Fig. 3

Cigarette smoke and polycyclic aromatic hydrocarbons affect Th17 differentiation and arthritis aggravation. a RLU (relative luminescence unit) in Hepa1–6.pGL4.43 cells induced by FICZ (300 nM) or cigarette smoke-enriched medium (CSEM: 5, 0.5, 0.05, 0.005 cigarettes/L). Mean ± SEM, n = 3, ^*P < 0.05, one-way ANOVA followed by Bonferroni post hoc test. b and c Naive CD4⁺ T cells from C57BL/6 mice were polarized under Th17 conditions under control medium or CSEM (five cigarettes/L) ± AHR antagonist (CH223191, 30 μM). (d) RLU in Hepa1–6.pGL4.43 cells induced by FICZ (200 nM) or benzo(b)fluoranthene (BFA: 200, 20, 2 and 0.2 nM). Data are mean ± SEM, n = 3, ^*P < 0.05 and ^***P < 0.001 by one-way ANOVA followed by Bonferroni post hoc test. e and f Naive CD4⁺ T cells were polarized under Th17 conditions in the presence of BFA (200 nM), FICZ (200 nM) or CSEM (five cigarettes/L). Mean ± SEM, n = 3, ^*P < 0.05, ^**P < 0.01, one-way ANOVA followed by Bonferroni post hoc test. g AIA mice were exposed to cigarette smoke (two cigarettes) or treated with BFA (100 μg/kg) or FICZ (90 μg/kg). Number of neutrophils in the joints, articular hyperalgesia and Th17 cells in DLNs. Mean ± SEM, n = 5/group, ^*P < 0.05, ^**P < 0.01, ^***P < 0.001, one-way ANOVA followed by Bonferroni post hoc test. Data are representative of two to three independent experiments. BFA benzo[b]fluoranthen, CH223191 1-Methyl-N-[2-methyl-4-[2-(2-methylphenyl)diazenyl]phenyl-1H-pyrazole-5-carboxamide, CSEM cigarette smoke-enriched medium, DLN draining lymph nodes, FICZ 6-formylindolo[3,2-b]carbazole, IL-17 interleukin 17