RT Journal Article SR Electronic T1 Effect of All-transretinoic Acid on Th17 and T Regulatory Cell Subsets in Patients with Ankylosing Spondylitis JF The Journal of Rheumatology JO J Rheumatol FD The Journal of Rheumatology SP 476 OP 483 DO 10.3899/jrheum.121100 VO 40 IS 4 A1 Katayoon Bidad A1 Eisa Salehi A1 Ahmadreza Jamshidi A1 Ali Akbar Saboor-Yaraghi A1 Mona Oraei A1 Alipasha Meysamie A1 Mahdi Mahmoudi A1 Mohammad Hossein Nicknam YR 2013 UL http://www.jrheum.org/content/40/4/476.abstract AB Objective. We compared Th17 and T regulatory cells in patients with ankylosing spondylitis (AS) and in healthy controls. The effect of all-transretinoic acid (ATRA) was studied on cultured CD4+ T cells of patients with AS compared to controls. Methods. Eighteen patients with AS and 18 age- and sex-matched healthy controls were included. CD4+ T cells were separated and cultured in conditions of anti-CD3 and anti-CD28 stimulation with and without ATRA. Intracellular and secreted cytokines, transcription factors, and gene expression were evaluated after 72 h. Results. The frequency of CD4+IL-17+ T cells was significantly higher in patients with AS compared to controls, and ATRA could significantly decrease it. The frequency of forkhead box protein 3 (FOXP3)+ retinoic acid-related orphan receptor γt (RORγt) negative T-bet negative CD4+ cells was significantly lower in cases compared to controls. Intracellular and secreted interferon-γ (IFN-γ) was not significantly different between cases and controls. ATRA significantly increased intracellular IFN-γ in cases but not in controls. Tumor necrosis factor-α (TNF-α) secretion was significantly higher and interleukin 10 secretion was significantly lower in culture supernatant of cases compared to controls. ATRA could significantly decrease TNF-α secretion in cases. Conclusion. Our findings favor a pathogenic role for Th17 cells in AS. Th1 cells did not seem to contribute in the pathogenesis of this disease. The effect of ATRA as an immunomodulator on deviated immune cells was associated with decreased inflammatory markers. This association could be a reason for a clinical trial of ATRA in patients with AS.