title: Effects of chlordimeform and its metabolite 4-chloro-o-toluidine on rat splenic T, B and tumoricidal effector cells.
abstract: The pesticide chlordimeform (CDF) and its metabolite 4-chloro-o-toluidine (4CT) are documented animal carcinogens. Various immunological and toxicological parameters were examined following CDF or 4CT exposure in Sprague-Dawley rats: spleen wt./body wt. ratio; spleen cells/mg; splenocyte viability; T and B cell mitogenesis; natural killer (NK) and natural cytotoxic (NC) cell activity. In this study CDF produced a dose-dependent inhibition of NK activity (E:T ratio 100:1). Significant decreases in NK activity also occurred at all CDF doses, while the spleen wt./body wt. ratio was reduced only by the highest CDF dose. The compound 4CT produced no significant effects on NK or NC activity. No changes were observed in spleen cells/mg, splenocyte viability, or in T and B cell proliferation mediated by concanavalin A (Con-A) and lipopolysaccharide (LPS), respectively, with either CDF or 4CT treatment. These results have demonstrated that CDF exposure has a selective effect on splenic functionally distinct tumoricidal effector cell populations, and that this effect is evident at 1 mg/kg, a dose not inconsistent with the maximum exposure levels in workers.
authors.affiliation: National Institute of Occupational Health and Safety, University of Sydney, N.S.W., Australia.
authors.forename: W D
authors.initials: WD
authors.lastname: Thomas
authors.forename: G K
authors.initials: GK
authors.lastname: Craig
authors.forename: N H
authors.initials: NH
authors.lastname: Stacey
mesh_terms: D000578:Amidines / Q000633:toxicity*; D000818:Animals; D001402:B-Lymphocytes / Q000187:drug effects / Q000276:immunology; D002742:Chlorphenamidine / Q000633:toxicity*; D007694:Killer Cells, Natural / Q000187:drug effects / Q000276:immunology; D008213:Lymphocyte Activation / Q000187:drug effects; D008214:Lymphocytes / Q000187:drug effects* / Q000276:immunology; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D013154:Spleen / Q000166:cytology / Q000187:drug effects / Q000276:immunology; D013601:T-Lymphocytes / Q000187:drug effects / Q000276:immunology; D013602:T-Lymphocytes, Cytotoxic / Q000187:drug effects / Q000276:immunology; D014052:Toluidines / Q000633:toxicity*
chemical_list: D000578:Amidines; D014052:Toluidines; C556393:p-chloro-o-toluidine hydrochloride; D002742:Chlorphenamidine