FCGR2B and rheumatoid arthritis: In our sample of healthy subjects, we detected that most individuals upregulate the expression of FcγRIIb from naïve to memory B cells (8/13), in contrast with the RA group, in which 15 out of 18 patients were downregulators (ΔMFI of greater than 10 between naïve and memory populations) (P = 0.029).