Greetings all, My co-authors and I are pleased to share three publications that were published during the course of my PhD project on the immunotoxicity of pharmaceuticals on harbour seal (Phoca vitulina) leukocytes.
Immunotoxic effects of single and combined pharmaceuticals exposure on a harbor seal (Phoca vitulina) B lymphoma cell line C. Kleinert, E. Lacaze, M. Mounier, S. DeGuise, M. Fournier The potential risk of pharmaceuticals in the environment to top-predators is still largely unknown. In this study, we assessed the immunotoxic effects of ten pharmaceuticals individually and as mixtures on a harbor seal (Phoca vitulina) B lymphoma cell line. A significant reduction in lymphocyte transformation was observed following an exposure to 12,500 μg/L 17α-ethinyl estradiol and 25,000 μg/L naproxen. Exposure to 12,500 μg/L 17α-ethinyl estradiol decreased the percentage of cell in the G0/G1 phase of the cell cycle while increasing the percentage of cells in the S phase. Carbamazepine exposure increased the amount of cells in the G2/M phase. Binary mixtures showed synergistic effects in lymphocyte transformation, cell cycle and apoptosis assays. Concentrations inducing toxic effects in the cell line were similar to those affecting fish in previous studies. The reduction of functional activities of the immune system may lead to altered host resistance to pathogens in free-ranging pinnipeds. http://www.sciencedirect.com/science/article/pii/S0025326X1730156X?via%3Dihub <http://www.sciencedirect.com/science/article/pii/S0025326X1730156X?via=ihub> T lymphocyte-proliferative responses of harbor seal (Phoca vitulina) peripheral blood mononuclear cells (PBMCs) exposed to pharmaceuticals in vitro C. Kleinert, E. Lacaze, M. Fortier, M. Hammill, S. DeGuise, M. Fournier The ubiquity of pharmaceuticals in the aquatic environment and the accumulation in organisms of lower trophic levels have been documented. The immunotoxicity of these xenobiotics has however been little investigated. This study assessed the effects of pharmaceuticals on the immune responses of harbor seal lymphocytes. Peripheral blood mononuclear cells isolated from harbor seal pups were exposed to varying concentrations of 17α-ethinyl estradiol (250–50,000 μg/L), naproxen (500–100,000 μg/L), carbamazepine (500–100,000 μg/L), erythromycin (750–150,000 μg/L) and binary mixtures thereof in vitro. All individual compounds and mixtures inhibited lymphocyte proliferation. Mixture effects were non-additive and predictive values overestimated the inhibition of proliferation. Male pups were more sensitive to erythromycin exposure. Comparison with the sensitivity of the 11B7501 cell line showed a higher sensitivity of pups to individual compounds and the inverse trend for mixtures. Based on our results, we hypothesize that pharmaceuticals may have the potential to in- terrupt immune functions in harbor seals. https://www.sciencedirect.com/science/article/pii/S0025326X17310287 <https://www.sciencedirect.com/science/article/pii/S0025326X17310287> Dose-response relationships in gene expression profiles in a harbor seal B lymphoma cell line exposed to 17α-ethinyl estradiol C. Kleinert, M. Blanchet, F. Gagné, M. Fournier The determination of changes in gene expression profiles with xenobiotic dose will allow identifying biomarkers and modes of toxicant action. The harbor seal (Phoca vitulina) 11B7501 B lymphoma cell line was exposed to 1, 10, 100, 1000, 10,000, or 25,000 μg/L 17α-ethinyl estradiol (EE2, the active compound of the contraceptive pill) for 24 h. Following exposure, RNA was extracted and transformed into cDNA. Transcript expression in exposed vs. control lymphocytes was analyzed via RT-qPCR to identify genes with altered expression. Our analysis indicates that gene expression for all but the reference gene varied with dose, suggesting that different doses induce distinct physiological responses. These findings demonstrate that RT-qPCR could be used to identify immunotoxicity and relative dose in harbor seal leukocytes. http://www.pagepressjournals.org/index.php/xeno/article/view/6702 <http://www.pagepressjournals.org/index.php/xeno/article/view/6702> If you have problems accessing the publications, please let me know and I’ll send you the pdfs. Best wishes, Christine Kleinert, Ph.D. NSERC Visiting Fellow in a Canadian Government Laboratory Environment and Climate Change Canada Centre Saint-Laurent, Montréal, QC, Canada Aquatic Contaminants Research Division // Division de la recherche sur les contaminants aquatiques
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