C5AR1 and autoimmune disease: Moreover, the recently discovered negative feedback loop in the C5aR-FcγR cross-talk via dectin-1 (18) and galactosylated IgG1 Abs (33) may have an impact on the development of glycoengineered intravenous immunoglobulins (IVIG) analogous to the IVIG preparations administered in autoimmune diseases as an anti-inflammatory therapy (34).