| Abstract: | The localization of immunogenic proteins of chromatin in the nuclease-hypersensitive regions was investigated by means of polyclonal antibodies against the total chromatin from cells N-nitrosodiethylamine-induced hepatoma of rats and from hepatocytes. The fractions released after digestion by Ca-dependent endonuclease and by exogenous DNasa-1 were considerably enriched with immunogenic determinants. The enrichment of nuclease-hypersensitive sites of chromatin with tumour-associated antigens was observed in experiments with antihepatoma antibodies preincubated with chromatin from the normal liver cells. Higher immunoreactivity was typical of fractions obtained during Ca-dependent endonuclease segregation of the hepatoma chromatin, while products of digestion by exogenous DNasa-1 possessed higher tumour specificity. |
