CTLA4 and rheumatoid arthritis: The results of the present in vitro study, together with the knowledges reported in previous studies by our group as well as other groups, suggest a contribution of CTLA4-Ig treatment in ameliorating the clinical aspect in RA patients through the downregulation of the pro-inflammatory status that is determined by the presence at peripheral and tissue level of M1 polarised monocytes/macrophages which cooperate in the high disease activity.