title: Cross-reactive cellular and humoral immunity to carcinogen-induced chicken fibrosarcomas. II. Effect of prior immunization with transplantable tumors on primary tumor incidence.
abstract: Primary carcinogen-induced (7,12-dimethyl-benz[a]anthracene; DMBA) tumor-bearing SC chickens (B2/B2) frequently showed antibodies in their sera which reacted with cells from their autochthonous tumors, chicken embryo fibroblasts (CEF), tumor cells from some transplantable tumor lines, and from approximately 10% of other primary tumors. Similar results were obtained by ELISA on glutaraldehyde-fixed cells and by immunofluorescence on viable cells. The serum antibody reactivity could be removed by absorption with CEF but not with non-cross-reacting primary tumor cells or a variety of normal tissues. Although sera from normal chickens never showed significant reactivity, a high percentage of sera from chickens that had been injected with DMBA but failed to develop detectable tumors showed antibody activity to a transplantable DMBA-induced tumor and to CEF. On the basis of previously established cross-reactivity patterns in protective immunity to transplantable carcinogen-induced fibrosarcomas, attempts were made to protect against chemical carcinogenesis by prior immunization with selected DMBA-induced transplantable tumors. Tumor-immune chickens showed a significant decrease in the development of tumors during the first 3 mo after injection of DMBA (p = 0.001) or methylcholanthrene (p = 0.033) when compared to controls. This resistance to tumor induction in immune chickens was correlated to the degree of tumor immunity to the immunizing tumor present 1 mo after carcinogen injection (p = 0.046). There was, however, no detectable difference in the incidence of tumors arising later than 3 mo after carcinogen injection. The reduction in tumor incidence in immune as compared to control chickens at 5 mo was therefore less striking than the reduction seen at 3 mo. Immunization with CEF and adjuvants or with adjuvants alone afforded no protection to tumor induction.
mesh_terms: D015127:9,10-Dimethyl-1,2-benzanthracene; D000818:Animals; D000912:Antibodies, Neoplasm / Q000096:biosynthesis; D000917:Antibody Formation; D000918:Antibody Specificity; D002642:Chick Embryo; D002645:Chickens; D003429:Cross Reactions; D005347:Fibroblasts / Q000276:immunology; D005354:Fibrosarcoma / Q000139:chemically induced / Q000276:immunology; D007114:Immunization; D008748:Methylcholanthrene; D012513:Sarcoma, Experimental / Q000139:chemically induced / Q000276:immunology*
chemical_list: D000912:Antibodies, Neoplasm; D008748:Methylcholanthrene; D015127:9,10-Dimethyl-1,2-benzanthracene