What are the pathogenic mechanisms of rheumatoid arthritis?
The pathogenesis of rheumatoid arthritis generally involves antigens entering the body and being first phagocytized by antigen-presenting cells such as macrophages. After processing and concentration, these antigens combine with molecules on the surface of phagocytic cells to form complexes. Once recognized by T-cell receptors, a three-molecule complex is formed. Through the secretion of various cytokines and mediators, inflammation and joint destruction occur. Meanwhile, activated B lymphocytes differentiate into plasma cells, secreting large amounts of immunoglobulins including rheumatoid factor and other antibodies. These form antigen-antibody immune complexes that further promote inflammatory responses.