PubMedDate not supplied
Certain immunopathologic conditions, such as hypersensitivity and autoimmune diseases, are characterized by quantitative and/or qualitative alterations of immune reactions. It is now believed that such immunologic disturbances generate from inadequate internal control and regulation of immunologic reactivity. Important member of the complex regulatory network that supervises an immune response are antibodies themselves. Since antibody is bifunctional molecule, its regulatory action deals with two separate molecular structures denoted as Fab and Fc portion. By Fab fragment, antibody interferes with the reaction with antigens, or participates in the regulatory idiotype/antiidiotype interactions. Fc-mediated regulation includes influence on complement activation cascade, formation and clearance of immune complexes, phagocytosis, ADCC activity, T- and B-cell function, cytokine profile, etc. In general, antibody triggers immune reactions, but also has the capacity to suppress them. Exogenous antibodies are likely to elicit similar effects on immune processes. Actually, it has been demonstrated that intravenously given immunoglobulins, particularly high-dose IgG, effectively combat harmful immune response in some chronic inflammatory and autoimmune disorders. Hence, preparations of immunoglobulins for intravenous use (IVIG) can be considered as an immunomodulatory agent. To achieve the property of modulating the immune response, IVIG products must contain intact (7S) IgG molecule and maintain sufficient concentrations in plasma.