[Tumor-associated hetero-organic antigens as markers of deranged cell differentiation and malignancy]

We used rat liver tissue slices and isolated hepatocytes to demonstrate that single exposures to a "weak" carcinogen 4-dimethylaminoazobenzol (DAB) or to a "strong" one, such as N-diethylnitrosamine (DENA), cause identical antigenic restructuring to occur. It presented as formation of membranous heteroorganic antigens of renal origin on hepatocyte surfaces. Antigens were associated with Zajdela's hepatoma; their synthesis lasted longer after exposure to DENA. They, however, were not identified in intact rat liver. Their synthesis, following single exposure, was assayed immunocytofluorimetrically. It is suggested that the antigens be used as markers of cell dysdifferentiation and malignancy and testing substances for carcinogenicity.