Immunochemical characterization of the specificities of two human monoclonal IgM's reacting with chondroitin sulfates.
We have studied the specificities of two human monoclonal, IgM containing sera, s/IgMMAC and s/IgMFIS, from patients with polyneuropathy. s/IgMMAC precipitates only with chondroitin sulfate C and not with A and B whereas s/IgMFIS is precipitated by chondroitins A, B (dermatan sulfate), and C. Inhibition assays using 2-acetamido-2-deoxy-3-O-(4-deoxy-beta-L-threo-hex-4-enopyranosyluroni c acid)-D-galactose and its 6- and 4-sulfate derivatives showed that the disaccharide 6-sulfate was the best inhibitor of precipitation of s/IgMMAC by chondroitin sulfate C, and the disaccharide 4-sulfate the best inhibitor of precipitation of s/IgMFIS by either chondroitin sulfates C or B. The nonsulfated disaccharide was a good inhibitor in each instance. D-Glucose 6-sulfate, Na2SO4, several sugar phosphates, and phosphate buffer also inhibited but to different extents with the s/IgMMAC and s/IgMFIS. All studies were carried out in 0.15M NaCl. The data indicate that both monoclonal proteins are antibodies comparable to the phosphorylcholine-binding myeloma proteins, and that the reactions show specificities above and beyond charge effects. The relation of various cross-reacting macromolecules to the monoclonal antibody was studied by diffusion in gels.
D000911:Antibodies, Monoclonal; D000936:Antigen-Antibody Complex; D002241:Carbohydrates; D002807:Chondroitin / Q000031:analogs & derivatives*; D002809:Chondroitin Sulfates / Q000276:immunology*; D000939:Epitopes / Q000032:analysis; D006801:Humans; D007075:Immunoglobulin M; D009422:Nervous System Diseases / Q000276:immunology*; D013329:Structure-Activity Relationship
D000911:Antibodies, Monoclonal; D000936:Antigen-Antibody Complex; D002241:Carbohydrates; D000939:Epitopes; D007075:Immunoglobulin M; D002807:Chondroitin; D002809:Chondroitin Sulfates