HLA-G and rheumatoid arthritis: Several studies in the last years have demonstrated that HLA-G plays an important role in the control of autoimmune/inflammatory diseases, such as multiple sclerosis (MS) [86], Crohn's disease (CD) [87], psoriasis [88], pemphigus [89], celiac disease [90], systemic lupus erythematosus (SLE) [91], asthma [92], juvenile idiopathic arthritis [93], and rheumatoid arthritis (RA) [94].