CD5 induces prolonged STAT3 activation and RORC transcription via elevation of IL-23R. (A) Naive T cells were stimulated with plate-bound antibodies directed against CD3/CD5 and cultured in presence in Th17-polarizing conditions (IL-23, IL-1β, IL-6, TGF-β, and anti-IFN-γ), or cultured without IL-23. At day 11, IL-17 production was measured by intracellular FACS staining, after 5 hours of restimulation with PMA, ionomycin, and BFA. Data shown are from 12 individual experiments using different donors. (B) Naive T cells were stimulated via CD3/CD28 or CD3/CD5 and cultured with Th17-inducing cytokines or without IL-23. Phospho-STAT3 levels were measured by FACS. Data shown are means from 6 individual experiments using different donors. (C) Phospho-STAT3 levels were measured at 72 hours by FACS, as described under panel B. Data shown are means from 6 individual experiments using different donors. (D-E) mRNA expression of RORC (D) and IL23R (E) was measured of naive T cells, stimulated as described under panel C. Data shown are mean ± SD of triplo measurement from one representative experiment of 2 individual experiments with different donors. (F) Naive T cells were stimulated with plate-bound antibodies directed against CD3/CD5 and cultured in presence in Th17 polarizing conditions without IL-23. IL-23R expression was measured by FACS at day 3, day 6, and day 11. Data shown are from 1 representative experiment of 4 independent experiments using different donors.