CTLA4 and rheumatoid arthritis: Based on these observations, the aim of the present study was to investigate the potential role of CTLA4-Ig to promote the shift from M1 to M2 in cultured human M1-polarised monocyte-derived macrophages (M1-MDMs) obtained from healthy subjects (HS) and RA patients, by evaluating the modulation of specific surface and functional markers.