TNF and rheumatoid arthritis: The expression of HLA class II genes, the major ligand in the MHC-II pathway, was significantly downregulated in classic monocytes in RA, and there was a relationship between this class of genes and inflammatory factors such as TNF and IL1B, and chemokines such as CCL3 and CCL3L1, and chemokines such as CCL3 and CCL3L1.