Gan Cao,1 Xiaoqi Yue,1 Shuhong Chi,2 Yanli Zhang1 

1Department of Pathogen Biology and Immunology, School of Basic Medical Sciences, Ningxia Medical University, Yinchuan, Ningxia, People’s Republic of China; 2Department of Rheumatology, The General Hospital of Ningxia Medical University, Yinchuan, Ningxia, People’s Republic of China

Correspondence: Yanli Zhang, Department of Pathogen Biology and Immunology, School of Basic Medical Sciences, Ningxia Medical University, 1160 Shengli Street, Yinchuan, Ningxia, 750004, People’s Republic of China, Tel/Fax +86951-6980122, Email zhangyl@nxmu.edu.cn

Background: Rheumatoid arthritis (RA) is a chronic autoimmune disease with abnormal differentiation of follicular helper T (Tfh) cells, Total alkaloids of Sophora alopecuroides Linn. (Leguminosae) (TASA) have potential effects on collagen-induced arthritis (CIA) mice, while the mechanism needs further elucidation. The purpose of this study is to explore the regulation of TASA on rheumatoid arthritis and related mechanism.
Methods: The proportion of Tfh and B lymphocytes in peripheral blood lymphocytes of RA patients was examined by flow cytometry. We constructed the collagen induced arthritis DBA/1J mice model. Between days 15 and 45 following the first immunization, the mice were treated intraperitoneally with saline, TASA (100, 50, and 25 mg/kg), and dexamethasone (DXM) for 30 days. Molecular biological techniques such as FCM, PCR, ELISA, and Western-blotting were used to examine Tfh cells and associated signal pathways.
Results: Our results indicated that the follicular helper T cells and B lymphocytes in rheumatoid arthritis patients were significantly increased compared with the healthy control. The percentage of Tfh cells are correlated with RA related inflammatory factors. Total alkaloids of Sophora alopecuroides Linn. could significantly attenuate joint swelling. Meanwhile, it reduced the frequencies of spleen Tfh, B lymphocytes and the expression of TLR2, TLR9, p-NF-κBp65, CXCR5, Bcl-6, ICOS of ankle joints in CIA mice.
Conclusion: Total alkaloids of Sophora alopecuroides Linn. may down-regulate the frequency and function of Tfh cells and inhibit GCB cells via TLRs/NF-κB signal pathway to relieve the immune-pathological progression of CIA mice.

Keywords: collagen-induced arthritis, C-X-C chemokine receptor type 5, total alkaloids of Sophora alopecuroides Linn., toll-like receptors