Modification of the immunologic properties of the cell surface

Living CF1 mouse-transplantable spontaneous mammary adenocarcinoma cells were modified with glutaraldehyde, formalin, 2,4,6-trinitrophenylate, Vibrio cholerae neurominidase, iodoacetate, heparin, histamine and adenosine 3'5'-monophosphate (cAMP), then used to immunize syngeneic CF1 mice. Animals immunized with the fixed (formalinized or glutaraldehyde fixed) neuraminidase-treated cells or the membrane of these cells, rejected two challenging doses of 10(8) viable unmodified adenocarcinoma cells. Animals immunized with adenocarcinoma cells treated with neuraminidase (170 IU/5x10(5) cells) or with the spontaneous adenocarcinoma-cell surface glycoprotein, rejected the first challenging dose but developed tumors and died on the second challenge with the viable untreated adenocarcinoma cells. Animals immunized with the adenocarcinoma cells pretreated with trinitrophenylate, glutaraldehyde or formalin, developed temporary resistance to the spontaneous mammary adenocarcinoma. Adenocarcinoma cells pretreated with NaF, iodoacetate, heparin, EDTA, Colchicine or histamine showed reduced oncogenicity and stronger resistance in mice to the development of a mammary tumor than to a smaller number (10(3) AdCa cells) of untreated viable adenocarcinoma cells. Cells treated with adenosine 3'5'-monophosphate accelerated tumor development.