Staphylococcus Aureus Protein A Immunoadsorption: The Rationale for Systemic Protein A Immunotherapy

Abstract

Summary: Staphylococcus aureus protein A (SPA) bound to affinity column matrixes has been used for extracorporeal immunoadsorption for the treatment of human autoimmune and neoplastic diseases. SPA is a bacterial immunoglobulin binding factor (IBF) that binds to the Fc region of antibody. The mechanism(s) of action of protein A immunoadsorption is not known. However, protein A immunoadsorption and systemic injection of SPA have demonstrated similar anti-neo6plastic and anti-retroviral responses in animals. Cellular Fc receptor (FcR) immunity and humoral IBF status are often abnormal in autoimmunity, cancer, and AIDS. The immunotherapeutic activity of protein A immunoadsorption may be produced by SPA leaching off columns and acting as a soluble FcR-like IBF, capable of influencing FcR dependent immunity. If this is the case then systemic SPA therapy may provide a simpler, safer, and more predicable mode of immunotherapy than immunoadsorption.

Keywords: :

• [K]Key [K]Words: Extracorporeal, Fc Receptor, Immunoglobulin Binding Factor, Staphylococcus Aureus Protein A.