CD4 and rheumatoid arthritis: In the case of rheumatoid arthritis, CD4+CD28- T lymphocytes produced higher levels of RANKL as compared with CD4+CD28+ T lymphocytes, and these senescent CD4+CD28- T lymphocytes showed a greater capacity to induce the differentiation of TRAP+ osteoclasts and bone resorption when compared with non-senescent CD4+CD28+ T lymphocytes [62].