Immunoadsorption
This chapter discusses the therapeutic procedure known as immunoadsorption (IA). Immunoadsorption utilizes columns that adsorb out immunoglobulin (Ig) by their binding to Staphylococcal protein A and this protein has a high affinity for the Fc portion of IgG and for aggregated IgG and IgG containing immune complexes. The effect of IA may not be secondary to antibody removal but by immunomodulation by the release of protein A into the patient, which subsequently induce B-cell depletion. Patients with congenital factor deficiencies can develop alloantibodies against the factor, known as inhibitors and some of these deficiencies place patients at risk for bleeding. Inhibitor suppression therapy is usually through immunosuppressants and inhibitor removal either through IA or plasma exchange and IA has been seen to be more effective than plasma exchange. IA is performed daily until antibody titer decreases and bleeding can be easily controlled with other therapeutic modalities. IA is also indicated in the treatment of idiopathic thrombocytopenic purpura and rheumatoid arthritis. © 2009 Elsevier Inc. All rights reserved.