LAUSR

Background Regulatory T-cells (T-reg) may play an inhibitory role in the development of autoimmune diseases (AID) by suppressing the immune response to autoantigens. Impaired or decreased T-reg and/or increased Th17 cells may be responsible for the development of AID. However, studies about the association of T-reg and systemic scleroderma (SSc) are limited and conflicting. Objectives Our aim is to determine whether there is a relationship between T-reg and Th-17 levels and disease activation in patients with SSc. Methods 17 patients with SSc who met 2013 ACR/EULAR SSc criteria were included in the study. Clinical and laboratory parameters, Rodnan skin scores, Valentini disease activity index, were evaluated in detail. Concurrent peripheral blood T-regs (CD4 +CD25+, CD4 +FOXP3+T reg, CD4 +CD25+FOXP3+T reg) and Th17 (IL-17 producing T cells) were studied. Age and sex matched 11 subjects were included as healthy control (HC) in this study. Results Fifteen of seventeen patients were female, median age was 52.8±9.36 years, median disease duration was 5.41±4.51 years. While skin involvement and Raynaud’s phenomenon were determined in all of the patients, esophageal involvement was determined in 13 of the patients (76.5%), digital ulcer in 2 patients (11.7%), and lung involvement in 14 (94.1%) patients. Median ESR level was 31.29±12.7 mm/hour, median CRP level was 0.573±0.474 mg/dl, median Valentini disease activity index was 3.23±1.53. The medications of the patients during the follow up period were as; nifedipine n=15 (88.2%), hydroxychloroquine n=14 (82.4%), corticosteroids n=14 (82.4%), azathioprine n=10 (58.6%), mycophenolate mofetil n=1 (5.9%), cyclophosphamide n=7 (41.2%). In comparison of SSc and HC, all the T-reg cell levels were significantly higher in SSc group than HC (p≤0.0001, p≤0.0001 and p≤0.0001, respectively). Although the levels of CD4 +IL-17 cells in SSc group were high compared to HC, it was not significant (p=0.100). A positive correlation between CD4 +IL-17+cell levels and CRP (r=0.613, p=0.009), a negative correlation between CD4 +CD25+T reg cell levels and dosage of corticosteroid (r=−0.513, p=0.035), a negative correlation between CD4 +CD25+T reg cell levels and platelet levels (r=−0.560, p=0.019) and a negative correlation between CD4 +CD25+FOXP3+T reg cell levels and platelet levels (r=−0.500, p=0.041) were determined. Conclusions In a cross-sectional study, it is rather difficult to explaine the meaning of increased T-reg cell in SSc patients. These results may be due to modification of the cells by immunosuppressive treatment. It might be more meaningful to evaluate T-reg cell before and after the treatment. References [1] Liu X, Gao N, Li M, Xu D, Hou Y, Wang Q, Zhang G, Sun Q, Zhang H, Zeng X. Elevated levels of CD4(+) CD25(+) FoxP3(+) T cells in systemic sclerosis patients contribute to the secretion of IL-17 and immunosuppression dysfunction. PLoS One. 2013;8: e64531. [2] Slobodin G, Ahmad MS, Rosner I, Peri R, Rozenbaum M, Kessel A, Toubi E, Odeh M. Regulatory T cells (CD4(+) CD25(bright)FoxP3(+)) expansion in systemic sclerosis correlates with disease activity and severity. Cell Immunol. 2010; 261:77–80. [3] Fenglio G, Battaglia F, Parodi A, Stringara S, Negrini S, Panico N, Rizzi M, Kalli F, Conteduca G, Ghio M, De Palma R, Indiveri F, Filaci G. Alteration of Th17 and Treg cell subpopulations co-exist in patients affected with systemic sclerosis. Clin Immunol. 2011139:249–57. Acknowledgements None Disclosure of Interest None declared