title: Distribution of a squamous cell lung carcinoma-associated antigen, KA-32, in human tissues and sera defined by monoclonal antibody KM-32.
abstract: The distribution of a variant of blood group A antigen recognized by a murine monoclonal antibody, KM-32, generated against human squamous cell lung carcinoma was investigated in various tissues and sera. By immunoperoxidase staining, the antibody was found to react with a number of lung carcinoma tissues of squamous cell carcinoma, adenocarcinoma, and small cell carcinoma, and several other tumor tissues. Positive staining was also observed in a small number of cells of some normal tissues, such as bronchiolar epithelium, gastrointestinal glands, and convoluted tubules of the kidney. The antibody could also be used in detecting macromolecular antigens, designated KA-32, in sera of patients with lung cancer. The antigen level in serum was determined by an inhibition assay using purified KM-32. The higher level of inhibition was seen in sera from over half of patients with lung cancer and patients with benign diseases when compared with those in sera from healthy adults. Purification of the antigen in serum was performed by gel filtration chromatography, immunoaffinity chromatography, and polyacrylamide gradient gel electrophoresis. Purified antigen exhibited a glycoprotein nature, and its molecular weight was estimated at more than 500,000.
mesh_terms: D000017:ABO Blood-Group System / Q000276:immunology*; D000911:Antibodies, Monoclonal / Q000276:immunology*; D000951:Antigens, Neoplasm / Q000032:analysis* / Q000302:isolation & purification; D002294:Carcinoma, Squamous Cell / Q000276:immunology*; D002846:Chromatography, Affinity; D002850:Chromatography, Gel; D006801:Humans; D007124:Immunoenzyme Techniques; D008175:Lung Neoplasms / Q000276:immunology*; D008970:Molecular Weight
chemical_list: D000017:ABO Blood-Group System; D000911:Antibodies, Monoclonal; D000951:Antigens, Neoplasm