Plasma exchange with selective immunoadsorption of anti-acetylcholine receptor antibodies.
Protein A-Sepharose and tryptophan polyvinyl alcohol affinity gels have been evaluated as possible agents for the selective, extracorporeal removal of anti-acetylcholine receptor (AChR) antibodies from the sera of patients with myasthenia gravis. Protein A-Sepharose was shown to be very effective. Specific anti-AChR IgG antibodies of subclasses 1 and 2 were reduced to the same extent (i.e. from 50 to 60% decrease) as the total IgG, although the latter was present at concentrations more than a 1000-fold greater. Anti-AChR antibody of subclass IgG3 was less effectively adsorbed. A full-scale in vitro experiment using one plasma volume and an automatic continuous monitor demonstrated the removal of 43% of the circulating anti-AChR antibodies and the IgG within 70 min, which is comparable to the amount removed by the present, unselective, membrane plasma exchange technique. In contrast, tryptophan polyvinyl alcohol was not effective in immunoadsorption under these circumstances.
Somnier
F E
FE
Department of Neurology, Rigshospitalet, Copenhagen, Denmark.
Langvad
E
E
D000906:Antibodies / Q000276:immunology*; D006801:Humans; D007074:Immunoglobulin G / Q000276:immunology / Q000378:metabolism; D007163:Immunosorbent Techniques; D009157:Myasthenia Gravis / Q000276:immunology / Q000628:therapy*; D010951:Plasma Exchange; D011950:Receptors, Cholinergic / Q000276:immunology* / Q000378:metabolism; D013205:Staphylococcal Protein A / Q000276:immunology / Q000378:metabolism
D000906:Antibodies; D007074:Immunoglobulin G; D011950:Receptors, Cholinergic; D013205:Staphylococcal Protein A