Figure 8: Orai1/Orai2-deficient T cells fail to induce colitis after adoptive transfer into lymphopenic host mice.

(a) Weight loss of Rag1^−/− host mice after transfer of 5 × 10⁵ CD4⁺CD25⁻CD62L^hi naive T cells from WT, Orai1^fl/flCd4cre, Orai2^−/− and Orai1^fl/flOrai2^−/−Cd4cre (DKO) mice; means±s.e.m. of 9–13 mice. (b) Representative macroscopic pictures of colon samples from mice described in a. Scale bar, 4 cm. (c) Representative H&E colon histologies 12 weeks after naive T cell transfer. Scale bar 75 μm. (d) Histopathological examination of H&E-stained colon sections as shown in c; means±s.e.m. of three to four mice. (e) Frequency of CD4⁺ T cells in spleen, mesenteric LNs (mLNs) and LP of Rag1^−/− mice 12 weeks after naive T cell transfer; means±s.e.m. of four to five mice. (f) Cytokine production by T cells isolated from spleen, mLNs and lamina propria (LP) 12 weeks after naive T cell transfer. Intracellular IFNγ, TNFα and IL-17 levels were measured after stimulation with phorbol myristate acetate (PMA)/ionomycin and analysed by flow cytometry; means±s.e.m. of four to five mice. *P<0.05; **P<0.005; ***P<0.001 using unpaired Student’s t-test in (e) and two-way analysis of variance (ANOVA) in f.