[Effect of carcinogenic exposure and tumor growth on the sensitization of C3HA mouse lymphoid cells to normal cell antigens]. / Vliianie kantserogennogo vozdeistviia i opukholevogo rosta na sensibilizatsiiu limfoidnykh kletok myshei linii C3HA k normal'nym kletochynm antigenam.

The reaction of indirect inhibition of peritoneal cell adherence to glass was used for a comparative study of the reactivity of lymph node cells of mice injected with the hepatocarcinogen DAB (4-dimethylaminoazobenzene) or with its non-carcinogenic analogue DEAB (4-diethylaminozobenzene, or with hepatoma 22a cells. The ability of regional lymph node cells to sensibilization towards normal cellular antigens decreased following the DAB treatment stronger and for a longer time period than that DEAB treatment. To the contrary, the growth or hepatoma 22a was accompanied by an appreciable sensibilization of cells of the regional lymph nodes. The results obtained are discussed in context of of the problem of immune surveillance of cytodifferentiation.

[Evaluation of the antigenic structural changes in the rat liver after a single carcinogenic exposure]. / K otsenke izmenenii antigennoi struktury pecheni krys posle odonkratnogo kantserogennogo vozdeistviia.

A single injection of hepatocarcinogen (4-dimethylaminoazobenzene) to rats resulted in antigenic rearrangement in rat liver, typical of hepatocellular tumors, whereas the treatment with a non-carcinogen isomere (4-diethylaminoazobenzene) did not have the same effect. It is assumed that antigenic rearrangement in hepatocytes caused by 4-dimethylaminoazobenzene might be due to its carcinogenity.

[Antigenic rearrangement in the liver of mice and rats as a result of simultaneous effect of the carcinogens]. / Antigennaia perestroika v pecheni myshei i krys vsledstvie odnokratnogo kantserogennogo vozdeistviia.

The antigenic structure of the livers of mice and rats after a single hepatocarcinogenic treatment was investigated using the immunodiffuse and immunofluorescent methods. The next day after carcinogen application changes characteristic of hepatocellular tumors were observed: decrease in the synthesis of organospecific antigens and intensification of the synthesis of heteroorganic antigens.

The effect of 4-dimethylaminoazobenzene and azobenzene on the immune reaction of male Sprague-Dawley rats.

The carcinogenic substance 4-dimethylaminoazobenzene and the non-carcinogen azobenzene were administered orally once a day to male Sprague-Dawley rats over several weeks at an equimolar dosage of 5-10(-5) moles/kg. Their immunological properties were examined in four different tests. The two substances suppress the cellular immune reactions of the rats already during the first month of treatment. The degree of efficiency of the immunosuppressive property decrease with the degree of antigenicity of the test antigen. Even a two-month treatment of the animals with the two substances had no evident influence on antibody formation. Correlations between the immune response and the carcinogenic effect were not demonstrable.

Detection of liver-bound metabolites of azocarcinogens by the use of anti-hapten antibodies.

The presence of the azocompounds, p-dimethylaminoazobenzene and 3'-methyl-p-dimethylaminoazobenzene, and p-amino-N-acetyl-N-methylaniline (or their metabolites) bound to components of the liver cells of rats fed a single large dose of each compound has been detected using rabbit antibodies raised against the p-azo-N-acetyl-N-methylaniline hapten in the indirect fluorescent antibody technique. Binding of these antibodies was seen on liver sections from rats fed any one of these compounds. When the anti-p-azo-N-acetyl-N-methylaniline antiserum was absorbed with either liver sediments or cytosol fractions from rats fed p-amino-N-acetyl-N-methylaniline, the antibodies reacting with the liver-bound compounds were removed from the antiserum. Also, absorption of the antiserum with liver sediments or cytosol fractions of rats fed either one of the azocompounds selectively removed all of the antibodies reacting with the livers of rats fed that compound but did not remove other antibodies that were still capable of reacting with liver cells of rats fed the other azocompound or p-amino-N-acetyl-N-methylaniline. Thus this antiserum appears to contain several different anti-p-azo-N-acetyl-N-methylaniline antibodies with different structural requirements for reaction. Some can react with the azocompounds or certain of their metabolites, while others require more of the p-azo-N-acetyl-N-methylaniline structure for reaction. Some of the antibodies appear to react with liver-bound p-dimethylaminoazobenzene but not with liver-bound 3'-methyl-p-dimethylaminoazobenzene, while still others react with 3'-methyl-p-dimethylaminoazobenzene but not with p-dimethylaminoazobenzene.