Figure 2. SFB-containing flora promotes the differentiation of arthritis-inducing Th1 cells.

(A–C) 4 days post transfer of naïve 5C.C7 T cells into mPCC, Cd3e^−/− hosts, the cells were stained for intracellular IL-17A and IFN-γ following a 3h stimulation with PMA and ionomycin. (A) Representative IFN-γ and IL-17A expression profiles, gated on live, CD4⁺Vβ3⁺ T cells and (B) frequencies of IFN-γ⁺ or IL17A⁺ CD4⁺Vβ3⁺ T cells in the indicated organs. (C) Frequencies of IFN-γ⁺ in CD4⁺Vβ3⁺ T cells in mLN of indicated host. Data (mean±SEM) pooled from 3 independent experiments each (n=7 (A–B) and n=5–6 (C) mice per group).

(D) 10 days post transfer of naïve CD45.1⁺ 5C.C7 T cells into 8–12 wk. old mPCC, Cd3e^+/+ hosts, the cells were stained for intracellular IL-17A and IFN-γ following a 5.5h stimulation with PMA and ionomycin. Frequencies of IFN-γ⁺ or IL17A⁺ in CD45.1⁺ CD4⁺Vβ3⁺ T cells in indicated organs. Data (mean±SEM) pooled from 5 independent experiments, each representing one pool of 6 RF-housed or 2 cohoused-RF(MPF) mice. RF(MPF) hosts were cohoused for 2 weeks with MPF-housed mPCC, Cd3e^−/− mice prior to T cell transfer.

(E) Bi-weekly arthritis scores of MPF-housed mPCC, Cd3e^−/− mice post transfer of naïve 5C.C7 WT or Ifng^−/− 5C.C7, Rag2^−/− T cells. Data (mean±SEM) pooled from two independent experiments (n=10 mice per group). See also Figure S2.