RESUMEN
Myasthenia gravis (MG) is usually caused by antibodies against the muscle acetylcholine receptor (AChR). Plasmapheresis and immunoadsorption are often used to treat non-responsive patients. Antigen-specific immunoadsorption would remove only the pathogenic autoantibodies reducing side-effects. We expressed AChR extracellular domain mutants for use as specific adsorbents, and characterized them. Antigenicity and capacity for autoantibody binding were improved compared to the wild-type proteins. Adsorption appeared to be fast, as high plasma flow-rates could be applied. The bound autoantibodies were eluted repeatedly, allowing column reuse, without compromise in efficiency. Overall, the adsorbents were specific, efficient and suitable for use in therapy.