In Vivo Localization of Anticarciiiogen Antibody in Organs of Carcinogen-treated Rats1

Rabbit antibody against the 2-azofluorenyl group was pre pared and purified specifically by the use of a hapten-specific solid adsorbent. These antibodies, when radiolabeled and in jected i.V., were shown to localize1specifically in the liver and kidney of rats previously injected with 2-aminofluorene and 2acetylaminofluorene and also in the liver and kidney of rats fed 2-acetylaminofluorene. The antibodies did not localize in the organs of untreated normal rats or of untreated rats with tumors induced by feeding 2-acetylaminofluorene. The latter rats had not received any carcinogen 0.5-1 year prior to the antibody injection. However, when such tumor-bearing rats were in jected with 2-aminoor 2-acetylaminofluorene prior to antibody injection, the antibodies did localize in the apparently healthy portions of liver and kidney, but not in the tumor itself. When rats were injected with 2,7-diacetylaminofluorene, 2-amino-7acetylaminofluorene, 2,7-diaminofluorene, 2,7-dinitrofluorene, and fluorene, they did not show any localization of the radiolabeled anti-2-azofluorene antibodies above control globulin. The anti-2-azofliiorenyl antibody was shown by radioimimmoeiectrophoresis experiments to be directed against the 2azofluorenyl group since the combination of antibody with antigen was inhibited by the presence of 2-aminofluorene and to a lesser degree by 2-acetylaminofluorene and 2-amino-7acetylaminofluorene. The results indicate that some eom]>onents of the hepatic cell surface are able to combine with fed or injected 2-amino fluorene and 2-acetylaminofluorene and then to fix the antibody in vivo, when the antibody is injected i.v. These components are not present in the tumor.