title: Induction of immunotoxicity in mice by polyhalogenated biphenyls.
abstract: Acute administration of Aroclor-1254 (500 mg/kg) or 3,4,5,3',4',5'-hexabromobiphenyl (HBB) (2-6 mg/kg) IP, profoundly inhibited the plaque forming response to subsequent challenge with sheep erythrocytes in Ah locus positive (C57Bl/6N or B6C3F1N) mice. These studies showed: the immunotoxicity results paralleled enzyme induction results insofar as HBB was approximately 100 times more potent than Aroclor 1254; neither Aroclor nor HBB treatment caused significant induction in the Ah locus negative DBA/2N mice; when B6C3F1 mice were challenged with sheep red blood cells (SRBC) 6 or 16 weeks post Aroclor 1254 treatment, substantial recovery of a PFC response was observed; when these compounds were administered to older (76-week-old) (B6C3F1 mice, severe depression of a PFC response was observed. In contrast to its profound depression of a PFC response, Aroclor-1254 (up to 1250 mg/kg) caused slight increases in lymphocyte proliferation induced by either T or B cell mitogens. A single 500 mg/kg dose of Aroclor-1254 also suppressed the ability of recipient B6C3F1 animals to reject a challenge with either the syngenic fibrosarcoma (PYB6) or the gram negative pathogen (Listeria monocytogenes).
mesh_terms: D000375:Aging; D000818:Animals; D001140:Aroclors / Q000633:toxicity*; D020111:Chlorodiphenyl (54% Chlorine); D003520:Cyclophosphamide / Q000494:pharmacology; D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism; D003640:Dealkylation; D005354:Fibrosarcoma / Q000276:immunology; D006462:Hemolytic Plaque Technique; D007109:Immunity / Q000187:drug effects*; D008089:Listeria monocytogenes / Q000276:immunology; D008213:Lymphocyte Activation / Q000187:drug effects; D051379:Mice; D008809:Mice, Inbred C3H; D008810:Mice, Inbred C57BL; D008811:Mice, Inbred DBA; D011078:Polychlorinated Biphenyls / Q000633:toxicity*
chemical_list: D001140:Aroclors; D020111:Chlorodiphenyl (54% Chlorine); D003520:Cyclophosphamide; D003577:Cytochrome P-450 Enzyme System; D011078:Polychlorinated Biphenyls; C027309:3,4,5,3',4',5'-hexachlorobiphenyl