Interferon Content of Intravenous Immunoglobulin: Variation Between Preparations

Abstract

The use of intravenous immune globulin (IVIG) has presented many confusing questions as to the diverse usefulness in various unrelated disease states. Approved for the primary immunodeficiencies, IVIG as a therapeutic modality has proven benefit in disease states such as Kawasaki's disease, Guillain-Barre syndrome, idiopathic thrombocytopenic purpura, and recently relapsing multiple sclerosis. Evidence has surfaced about the ability of IVIG to reverse the immune responses, much like steroids, through such modalities as Fc receptor blockade and cytokine regulation. We present further evidence of the as yet unknown array of cytokines present in commercial IVIG preparations. The cocktail-like availability of these cytokines have the potential to influence immune mechanisms; specifically, levels of the interferons present in commercial IVIG products vary from source to source. Without knowing the cytokine profile present in the products, the usefulness of these IVIG preparations in altering immune function may be misleading to researchers and clinicians.