CD4 and rheumatoid arthritis: The level of reduced glutathione in intestinal tissue increased significantly and the ratio of CD4+/CD8+ in different parts of intestinal mucosal immunity decreased significantly after 8 weeks of TGP administration in this study, suggesting that TGP may regulate lymphocytes in intestinal mucosal immunity and epithelial barrier through glutathione metabolism, thereby exerting an anti-RA effect.