Developmental immunotoxicity of di-n-octyltin dichloride (DOTC) in an extended one-generation reproductive toxicity study

Department of Toxicogenomics, Maastricht University, Maastricht, The Netherlands.
Toxicology Letters (Impact Factor: 3.26). 07/2011; 204(2-3):156-63. DOI: 10.1016/j.toxlet.2011.04.027
Source: PubMed


Developmental immunotoxicity assessment is considered ready for inclusion in developmental toxicity studies. Further evaluation of proposed and additional assays is needed to determine their utility in assessing developmental immunotoxicity. In this study, a wide range of immunological parameters was included in an extended one-generation reproductive toxicity protocol. F(0) Wistar rats were exposed to DOTC via the feed (0, 3, 10, and 30mg/kg) during pre-mating, mating, gestation and lactation and subsequently F(1) were exposed from weaning until sacrifice. Immune assessments by several immune parameters were performed at PNDs 21, 42 and 70. The T cell-dependent antibody response to Keyhole Limpet hemocyanin (KLH) was assessed following subcutaneous immunizations with KLH on PNDs 21 and 35 and the delayed-type hypersensitivity response (DTH) against KLH was evaluated at PND 49. No effects were found on PND 21. While effects on lymphocyte subpopulations in the thymus were only observed in the 30mg/kg group on PND 42, effects on lymphocyte subpopulations in the spleen were found in the 30mg/kg group on both PNDs 42 and 70. The DTH response already showed an effect at 3mg/kg and was the overall critical endpoint. The results from this study support the inclusion of splenocyte subpopulation parameters in developmental toxicity studies and identified the DTH response as an important functional parameter.

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Available from: Andre Wolterbeek, Sep 25, 2014
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    • "Of all compounds tested in this study only DOTC inhibited CYP17 activity in H295R assay but not in the PACM assay. Regarding this inhibition of CYP17 by DOTC it is interesting to note that this compound is primarily a developmental immunotoxicant (Tonk et al., 2011a, 2011b). Organotin compounds are known to interfere with the male– female sex hormone balance by binding to various enzymes in this steroidogenic pathway (Cooke, 2002; Heidrich et al., 2001; Lo et al., 2003). "
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