SAT0183 STATUS OF LYMPHOCYTE SUBSETS IN PERIPHERAL BLOOD OF PATIENTS WITH PRIMARY SJÖGREN’S SYNDROME AND THEIR CHANGES AFTER RECEIVING OUR NEW IMMUNOREGULATORY COMBINATION THERAPY: A RETROSPECTIVE CROSS-SECTIONAL STUDY

Background:Primary Sjögren’s syndrome (pSS) is a chronic inflammatory autoimmune disease mainly involving exocrine glands and involving multiple organs and systems1. Recent studies have reported that peripheral lymphocyte subsets such as Th1, Th2, Th17, and regulatory cells (Tregs), have been implicated in the pathogenesis of pSS2. However, the detailed statuses of lymphocyte subsets of pSS patients remain to be clearly evaluate and effects of immunomodulatory therapies on the lymphocyte subsets are unknown.Objectives:To explore the pathogenesis and evaluate the therapeutic effect of immunomodulatory drugs (IMiDs) by comparing the changes of lymphocyte subsets in peripheral blood (PB) before and after treatment.Methods:This study included 1,221 pSS patients and 206 healthy controls (HCs). Among these patient, 759 patients were received our new immunoregulatory therapies such as low-dose interleukin-2, rapamycin, metformin, retinoic acid etc. The absolute numbers of T, B, NK, CD4+T, CD8+T, Th1, Th2, Th17 and Tregs in PB of these subjects were detected by flow cytometry combined with standard absolute counting beads. Data were expressed as mean ± standard deviation to the distribution. Independent-samples T test and paired-samples T test were applied.Pvalue <0.05 were considered statistically significant.Results:The absolute numbers of circulating Tregs as well as T, NK cells in pSS patients were significantly lower than those of HCs (P<0.05). After immunoregulatory combination treatments, the number of Tregs was significantly increased (P<0.05). Though the absolute numbers of T, NK, CD4+T, CD8+T, Th1, and Th17 cells were also increased to some degree (P<0.05), the increased amount of Tregs was much more than other cells, resulting a new balance between pro- and anti- inflammatory lymphocyte homeostasis.Conclusion:The decrease of peripheral Tregs played an important role in the pathogenesis of primary Sjögren’s syndrome. Immunoregulatory combination therapies promoted the increase of Tregs and might help for the recovery of pSS.References:[1]Mariette X, Criswell LA. Primary Sjogren’s Syndrome. N Engl J Med 2018;378(10):931-39. doi: 10.1056/NEJMcp1702514 [published Online First: 2018/03/08][2]Miao M, Hao Z, Guo Y, et al. Short-term and low-dose IL-2 therapy restores the Th17/Treg balance in the peripheral blood of patients with primary Sjogren’s syndrome. Ann Rheum Dis 2018;77(12):1838-40. doi: 10.1136/annrheumdis-2018-213036 [published Online First: 2018/06/25]Acknowledgments :None.Disclosure of Interests:None declared