Experimental demyelination of nerve induced by serum of patients with neuropathy and an anti-MAG IgM M-protein.
Demyelination of feline sciatic nerve was induced by intraneural injection of serum from three patients with neuropathy and an IgM M-protein that reacted with myelin-associated glycoprotein (MAG). Demyelination exceeded that induced by serum from 18 other individuals, including six IgM M-proteins unreactive with MAG. The myelinolytic effect required active human complement and was abolished by exposure of serum to homogenate of human peripheral nerve that removed 90% of the M-protein. Immunofluorescence studies demonstrated deposition of the injected M-protein and complement on the surface of myelin sheaths, implying that the M-protein reacted with epitopes of myelin exposed to the extracellular space.
D000818:Animals; D001327:Autoimmune Diseases / Q000276:immunology; D002415:Cats; D003165:Complement System Proteins / Q000032:analysis / Q000276:immunology; D003711:Demyelinating Diseases / Q000209:etiology* / Q000276:immunology / Q000473:pathology; D006023:Glycoproteins / Q000032:analysis / Q000276:immunology*; D006801:Humans; D007120:Immunochemistry; D007075:Immunoglobulin M / Q000032:analysis / Q000276:immunology*; D009185:Myelin Proteins / Q000032:analysis / Q000276:immunology*; D018992:Myelin-Associated Glycoprotein; D010265:Paraproteinemias / Q000276:immunology*; D010525:Peripheral Nerves / Q000276:immunology / Q000473:pathology
D006023:Glycoproteins; D007075:Immunoglobulin M; D009185:Myelin Proteins; D018992:Myelin-Associated Glycoprotein; C023587:protein M (glycoprotein); D003165:Complement System Proteins