An Adsorbent for Extracorporeal Elimination of Pathogenic Autoantibodies

This work investigated the potential use of benzoic acid (BA)-based immunoadsorbent, a hydrophobic adsorbent, for autoantibodies selective adsorption therapy. The adsorbent was assessed through chromatographer and batch system assays in terms of adsorption capacity, selectivity for both polycloneantibodies in normal human plasma and pathogenic antibodies in patients´ sera. For human immunoglobulin G (IgG), capacities of >30 mg/mL at 10% breakthrough (pH 7.4, linear flow rate of 212 cm/hr) were regularly achieved without adding salt. Removal percentage of immunoglobulins (Igs) in plasma samples was 34.2±4.0%, while that of albumin was less than 3% at the ratio of 5 sample volumes per adsorbent volume. Rheumatoid factors in serum samples from 8 rheumatoid arthritis (RA) patients were eliminated at different degrees after treatment by the adsorbent. The results indicated that BA-based agrose was effective in selectively adsorbing human antibodies from plasma, could thus have a potential ability to eliminate pathogenic autoantibodies in apheresis.