Immunogenicity and antigenicity of immunoglobulins: detection of human immunoglobulin light-chain carbohydrate, using concanavalin A.
Concanavalin A binding to glycoprotein bands on nitrocellulose blots was used to detect mannose, sorbose, N-acetylgalactosamine and/or glucose residues on 100% (31/31) of human Bence Jones protein light chains, following sodium dodecyl sulphate-polyacrylamide gel electrophoresis. All (20/20) light chains form IgG myeloma proteins and light chains from a preparation of normal polyclonal human IgG were also bound by concanavalin A. The specificity of concanavalin A for glycoproteins was demonstrated by its binding to human Fc fragments and a human monoclonal anti-Rhesus D antibody (REG-A), but not to human albumin pFc' fragments and aglycosylated REG-A derived from cells grown in the presence of the glycosylation inhibitor tunicamycin. These results suggest that all Bence Jones proteins and light chains from myeloma IgG proteins contain mono- or oligosaccharides linked O-glycosidically to serine or threonine residues.
D000116:Acetylgalactosamine / Q000032:analysis; D000911:Antibodies, Monoclonal / Q000032:analysis; D001536:Bence Jones Protein / Q000032:analysis; D002241:Carbohydrates / Q000032:analysis*; D003208:Concanavalin A; D004591:Electrophoresis, Polyacrylamide Gel; D005947:Glucose / Q000032:analysis; D006801:Humans; D007118:Immunoassay; D007141:Immunoglobulin Fc Fragments / Q000032:analysis; D007074:Immunoglobulin G / Q000032:analysis; D007147:Immunoglobulin Light Chains / Q000032:analysis*; D008358:Mannose / Q000032:analysis; D012204:Rh-Hr Blood-Group System / Q000276:immunology; D013013:Sorbose / Q000032:analysis
D000911:Antibodies, Monoclonal; D002241:Carbohydrates; D007141:Immunoglobulin Fc Fragments; D007074:Immunoglobulin G; D007147:Immunoglobulin Light Chains; D012204:Rh-Hr Blood-Group System; D003208:Concanavalin A; D001536:Bence Jones Protein; D005947:Glucose; D000116:Acetylgalactosamine; D013013:Sorbose; D008358:Mannose