ABSTRACT
Polyspecific immunoglobulin G (IgG) for intravenous use (IVIG) was originally developed as a substitution therapy for hypo-and agammaglobulinemic patients. However, Imbach and colleagues observed that IVIG supplementation was in fact effective as a treatment in idiopathic thrombocytopenia purpura (ITP)1. This has led to the widespread use of IVIG in various immune diseases. Yet, the biological effects of IVIG explaining its efficacy in these diseases are still poorly understood, although they are frequently referred to as ‘immunemodulatory’ effects. One could postulate various mechanisms for these immunemodulatory effects of IVIG, some of which are dependent on a productive interaction of the Fcγ portion of infused immunoglobulin with the Fcγ receptors on effector cells1-4 or with proteins of the complement system5,6. Here we discuss briefly some of our studies of the interaction of IVIG with Fc receptors.
