[Demonstration of antibodies against tumor-associated antigens in the serum patients with bronchogenic carcinoma using anticomplement immunofluorescence on xenotransplants of human tumors].

209 sera of tumor-bearing patients and 133 control sera were tested by anti-complement immunofluorescence (ACIF) on 2 xenotransplants of human bronchogenic cancer and on 2 xenotransplants of rectum carcinoma passaged in nu/nu mice. Testing of sera from patients with bronchogenic carcinoma resulted in a positive reaction with the xenotransplants of bronchogenic cancer in 48.5 to 58.5%, and sera of patients with digestive tract cancer in 6.6 to 16.1%. On xenotransplants of rectum carcinoma 73.2 to 78.1% of the sera from patients with bronchogenic carcinomas and 22.6 to 29.1% of the sera of patients with digestive tract cancer reacted positively. Control sera were positive dependent on the xenotransplants in 2.0 to 12.5%. These results indicate that there are antibodies in the sera of tumor-bearing patients against one or more non organ specific tumor-associated antigen(s) occurring in an elevated concentration in carcinomas of the digestive tract than in bronchogenic carcinomas. After absorption of the sera with homogenates of bronchogenic carcinoma and liver metastases of colon carcinoma the reaction was inhibited in the ACIF, reaching control values.