title: Antibody specific for lung cancer cells detected in sera of patients with bronchogenic carcinoma.
abstract: Two hundred and seventy-one sera from patients with lung cancer were checked to determine whether they exerted a blocking or potentiating effect on normal lymphocyte-cytotoxicity against lung cancer targets using a microcytotoxicity assay. A blocking effect was observed in 15 of 49 untreated patients (30.6%), but a potentiating effect was detected in 10 of 49 (20.4%). Such effects were not correlated with stages of the disease or the clinical status of patients. Such a blocking effect was also detected in patients with pneumonia, pulmonary tuberculosis, benign mediastinal tumor and malignancies other than lung cancer, but the potentiating effect could not detected in such patients. Using an indirect membrane immunofluorescence test, IgG antibodies against QG-56 of a lung cancer cell line were detected in 54.3% of potentiating sera and in 20.5% of blocking sera. Such antibodies were cross-reactive with 2 other lung cancer cell lines and one of 4 uterine cancer lines, however, no cross-reaction was observed against 3 breast cancer lines, 3 of 4 uterine cancer lines, one malignant melanoma line and one pancreas cancer line. The effector cells exerting the potentiating effect were identified as non-adherent, Fc receptor-bearing lymphocytes. Therefore, the potentiating effect might be typical antibody-dependent cell-mediated cytotoxicity.
mesh_terms: D000912:Antibodies, Neoplasm / Q000032:analysis*; D000918:Antibody Specificity; D000920:Antibody-Dependent Cell Cytotoxicity; D001769:Blood; D002283:Carcinoma, Bronchogenic / Q000276:immunology*; D002460:Cell Line; D003429:Cross Reactions; D003602:Cytotoxicity, Immunologic; D005260:Female; D006801:Humans; D007074:Immunoglobulin G / Q000032:analysis; D008175:Lung Neoplasms / Q000276:immunology* / Q000628:therapy; D008214:Lymphocytes / Q000276:immunology; D008297:Male; D011961:Receptors, Fc / Q000032:analysis
chemical_list: D000912:Antibodies, Neoplasm; D007074:Immunoglobulin G; D011961:Receptors, Fc