FCGR2B and systemic lupus erythematosus: As the gut leakage brought on spontaneous endotoxemia in full-blown FcgRIIb-/- mice at 40 wks old and in patients with active lupus [5], FcgRIIb-/- mice at 24 wks old, which demonstrated only increased anti-dsDNA but not lupus nephritis, were selected for use in the NSAIDs evaluation.