Tilapia (Oreochromis niloticus) and rodents exhibit similar patterns of inhibited antibody production following exposure to immunotoxic chemicals.
The hemolytic plaque forming cell assay (PFC), a measure of ability to produce specific antibodies following challenge with antigen, is a powerful predictor of immunosuppression in chemical-exposed rodents. The efficacy of this assay for predicting humoral immunosuppression in non-rodent species remains unknown. In the present report, tilapia (Oreochromis niloticus) were exposed to 9 chemical agents known to inhibit antibody production in mice (benzo[a]pyrene, 7,12-dimethylbenzanthracene, 2,3,7,8-tetrachlorodibenzo-p-dioxin, dimethyl nitrosamine, cadmium chloride, azathioprine, hexachlorocyclohexane, T2 mycotoxin and toluene) and 5 chemical agents which do not inhibit this response (oxymethalone, acetonitrile, diethylstilbesterol, t-butylhydroquinone and formaldehyde). Eight of 9 agents which inhibit antibody production in rodents caused decreased PFC responses in fish. All 5 compounds with negative humoral effects in rodents were also negative in fish. Thus, 13/14 chemical agents tested gave similar results in tilapia as reported in rodents, suggesting a comparable pattern of humoral immunosuppression in chemical-exposed tilapia to that seen in laboratory rodent models.
Smith
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Department of Biomedical Sciences and Pathobiology, Virginia-Maryland Regional College of Veterinary Medicine, Virginia Polytechnic Institute and State University, Blacksburg 24061-0442, USA.
Schurig
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GG
Smith
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Holladay
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SD
D000818:Animals; D000917:Antibody Formation / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D006462:Hemolytic Plaque Technique; D007166:Immunosuppressive Agents / Q000633:toxicity*; D066298:In Vitro Techniques; D012756:Sheep; D017210:Tilapia / Q000276:immunology*
D007166:Immunosuppressive Agents