CD4 and rheumatoid arthritis: The rheumatoid synovium consists of a large number of CD4+ T cells and activation of CD4+ T cells is considered to be antigen driven, signifying a pathogenic function for T cells in this joint disease.71 It is proposed that persistent inflammation in RA is due to the interactions among T-cells, macrophages, and fibroblasts.72 Breach of self-tolerance and activation of naive antigen specific T cells by antigen presenting cells particularly by dendritic cells is a crucial step in the development of autoimmune disorders.73