Lymphocyte cytotoxicity in x-irradiation-induced rat small bowel adenocarcinoma. III. Blocking by 3 M KCL extract.
Hypertonic salt extracts (3 M KCl) of x-irradiation-induced Holtzman rat small bowel adenocarcinomas blocked the in vitro destruction of allogeneic cultured cells of this malignancy by sensitized lymphoid cells obtained from tumor-bearing animals. The protective effect were mediated by a blocking action at both the effector and the target cell level. The extracts were separated into 50% ammonium sulfate soluble and insoluble fractions with the soluble fraction being more effective in blocking the cytotoxic responses through interaction with the lymphoid cells whereas the insoluble one had a greater effect upon tumor target cells. Associated with both fractions was the oncofetal glycoprotein previously identified with the cellular membrane of this x-ray-induced malignancy. Immunoglobulins were identified with insoluble fraction; some were able to bind the oncofetal protein, thus clasifying it as a fetal antigen. The protective effects of the soluble fraction and this neoantigen were found to be citric acid labile, whereas the effects due to the insoluble fraction were unchanged.
D000230:Adenocarcinoma / Q000276:immunology*; D000645:Ammonium Sulfate; D000818:Animals; D000951:Antigens, Neoplasm; D003602:Cytotoxicity, Immunologic / Q000187:drug effects; D005333:Fetus / Q000276:immunology; D007414:Intestinal Neoplasms / Q000276:immunology*; D008214:Lymphocytes / Q000187:drug effects / Q000276:immunology*; D008297:Male; D009374:Neoplasms, Experimental / Q000276:immunology; D009381:Neoplasms, Radiation-Induced / Q000276:immunology*; D011189:Potassium Chloride / Q000494:pharmacology*; D051381:Rats
D000951:Antigens, Neoplasm; D011189:Potassium Chloride; D000645:Ammonium Sulfate