Anti-tumor antibodies in lung cancer patients. Immunofluorescence study using various indicator cells.

By means of indirect immunofluorescence a number of primary lung cancer patient sera and control sera were tested for anti-tumor antibody activity on living tumor cells as a substrate. Antibodies against surface antigens were the most frequently detected in autologous system (in 65%) on cells derived from fresh surgical material of lung cancer. They were also found in 50% of cases using tumor cells from primary short-term culture. When established cell line of lung cancer was used (E-14) in allogeneic system, the antibodies were detected in only 22% of examined lung cancer sera. Absorption of positive sera with homogenates of normal tissues did not abolish their specific activity. Positive reactions were confined to squamous cell type of bronchogenic carcinoma.