AB0047 T-CELL IMMUNOGLOBULIN AND MUCIN DOMAIN–CONTAINING PROTEIN 3 EXPRESSION IN REGULATORY T CELLS OF ANKYLOSING SPONDYLITIS PATIENTS AND THE CORRELATION WITH DISEASE ACTIVITY

Abstract

Background:Ankylosing spondylitis (AS) is a chronic inflammatory autoimmune disease. Regulatory T cells have been found in peripheral blood of AS patients. However, there is a controversy regarding the relative number and function of regulatory T cells in AS. T-cell immunoglobulin and mucin domain–containing protein 3 (Tim-3) is a negative immune regulator that participates in immune responses and widely expresses on a variety of immune cells. Many studies have shown that Tim-3 participates in tumors, infections, hematological system diseases and autoimmune diseases (such as systemic lupus erythematosus, rheumatoid arthritis, autoimmune hepatitis, etc). While there has not yet clinical trials with large samples to verify whether or not Tim-3 is involved in the incidence of AS and the relationship between the disease activity of AS and the expression of Tim-3 in regulatory T cells.Objectives:The present study aimed to identify the Tim-3 expression in regulatory T cells in AS patients, and the association between Tim-3 and the disease activity of AS.Methods:There were 47 patients diagnosed as AS and 51 age- and sex-matched healthy controls (HCs) from Guangdong Second Provincial Central Hospital enrolled in the study. The clinical information of the AS patients was recorded in detail and the disease activity was calculated. The positive expression rates and medium fuorescence intensity (MFI) of Tim-3 in regulatory T cells were examined by fow cytometry. Statistical approaches were used to analyze the experimental data of patients and controls.Results:The Treg cells level was significantly decreased in AS patients compared to the healthy controls (5.14±0.27 vs 4.38±0.23, P = 0.032, Fig 1 A). Tim-3 expression in regulatory T cells was lower in AS patients than the HCs (63.29±2.39 vs 52.56±3.49, P = 0.013, Fig1 B). And Tim-3 MFI in regulatory T cells was significantly decreased too(1355.04±171.44 vs 859.19±105.11, P = 0.016, Fig1 C).The Treg cells ratio negatively correlated with BASDAI (r=-0395, p=0.014) and BASFI (r=-0391, p=0.015) in AS patients. However, the Tim-3 expression in the Treg cells has no correlation with diseases activity in patients.Conclusion:According to the test results, we could confirm that regulatory T cells participate in the progression of AS, and it has negative relationship with disease activity. Tim-3 can express in Treg, but whether Tim-3 can be used as a potential target for AS treatment in future need further verified.Disclosure of Interests:None declared