FCGR2B and arthritic joint disease: Overexpression of FcγRIIb on B cells, mimicking the endogenous upregulation that occurs during B cell activation, was shown to protect mice in models of arthritis and SLE.13,29 We, therefore, designed experiments to examine the effect of B cell FcγRIIb overexpression on atherosclerosis using this previously described FcγRIIb-Btg mouse.