Immunohistological Detection of Fucosyl-Gm1 Ganglioside in Human Lung Cancer and Normal Tissues with Monoclonal Antibodies

Abstract With the aid of a highly specific murine monoclonal antibody, F12, an immunofluorescence method was elaborated that allowed sensitive and specific detection of the ganglioside antigen fucosyl-G M1 (IV 2 FucII 3 NeuAcGgOse 4 Cer) in different types of human lung cancer and normal tissues. Nineteen of 21 cases of small cell lung cancer were positive with the F12 immunofluorescence method as compared to 2 of 10 squamous epithelial cell lung cancers and 1 of 5 large cell lung cancer specimens. Specimens of lung adenocarcinoma (8 cases) and bronchial carcinoid (3 cases) were all negative, as were 2 examined cases of neuroblastoma. No fucosyl-G M1 could be detected in normal lung and bronchus. However, in thymus, spleen, and lamina propria of the small intestine sparsely distributed clusters of small round cells were stained as well as intramural ganglionic cells of the small intestine and islet cells of the pancreas. All other normal tissues tested were negative. Results obtained with immunofluorescence closely agreed with immunochemical determination of fucosyl-G M1 in lipid extracts of tissues. Our findings suggest that fucosyl-G M1 is strongly associated with small cell cancer of the lung and demonstrate that this tumor-associated antigen can be detected with high sensitivity and specificity with an immunofluorescence method based on the use of the F12 monoclonal antibody.