Immunosuppressive Effects of Benzidine in BCF Mice

Abstract

Benzidine (4, 4′-diaminobiphenyl) is an acknowledged carcinogen, employed industrially in the synthesis of dyes as well as analytic reagents in various laboratory tests (rev. by Haley, 1975). Benzidine exposure is associated with urinary bladder tumors in humans and with hepatomas, mammary tumors, and, to a lesser extent lymphomas in rodents (IARC, 1982a, b; Baker, 1953; Grieswold, et al,., 1968). Numerous studies have suggested that the immune response can modulate the growth of antigenic tumors (rev. by Stutman, 1975). Thus, it follows that an increased incidence or progression of neoplastic disease may occur by chemical carcinogens that are also immunosuppressive. In this respect, a strikingly high percentage of carcinogens are also immunosuppressive in experimental studies including diethylstilbestrol, certain polycyclic aromatic hydrocarbons, cyclophosphamide, benzene, nitrosamines, and phenytoin (rev. by Dean, et al., 1982). Furthermore, studies in laboratory animals have demonstrated an enhanced incidence of tumors induced by UV, methylcholanthrene or benzo(a)pyrene in mice treated with immunosuppressive agents (e.g. Kalland and Forsberg, 1981; Stjensward, 1966; Outzen, 1980). Of particular relevance to the present studies is a recent report which indicated a direct relationship between immunosuppression and neoplasia in workers engaged in the manufacture of benzidine (Gorodilova and Mandrik 1978).