AB0381 Expression of Toll-like Receptors and Distribution of Immune-Cells in Rheumatoid Synovial Tissues of The Patients Treated by Abatacept

BackgroundRheumatoid arthritis (RA) is a progressive chronic autoimmune and autoinflammatory disease affecting multiple joints simultaneously1. Abatacept (ABT) which is cytotoxic T-lymphocyte-associated protein (CTLA) 4-Ig agent is one of biologics2.ObjectivesThe aim of this study is to examine the effect of ABT for evaluating immune-reactive cells with toll-like receptors in the synovial tissue samples of RA patients with ABT therapy (ABT groups) compared to them with non-biological therapy (Non-BIO groups).MethodsSynovial tissue samples of 20 RA (10 ABT and 10 Non-BIO samples) were immunohistochemically stained with TLR+ and immune-reactive cells including T cells (CD2), B cells (CD20), macrophage (CD68), conventional dendritic cells (cDC; S100, DC-LAMP), regulatory T cells (FoxP3) and indoleamine 2,3-dioxygenase+ cells (IDO). Positive cells were counted per 10 fields (x 200) by microscopy. TLR positive cells were analyzed by double Immunofluorescent methods with T cell, B cell, macrophage, cDC and plasmacytoid DC (pDC; CD123)-markers and IDO. Synovial inflammation was estimated by Krenn grading score.ResultsABT and non-BIO group was shown the similar grading scores (2.3 vs 2.0), DAS28CRP4 (5.1 vs 4.3) and CRP (1.3 vs 0.9). IDO+ and FoxP3+ cells, not CD3+, CD20+ and CD68+ cells were correlated significant with DAS28CRP (4) in lymphoid aggregation in ABT groups (p