Relationships between in vitro lymphoproliferative responses and levels of contaminants in blood of free-ranging adult harbour seals (Phoca vitulina) from the North Sea

• Published in: Aquatic Toxicology
• Main Authors: Dupont, Aurélie, Siebert, Ursula, Covaci, Adrian, Weijs, Liesbeth, Eppe, Gauthier, Debier, Cathy, De Pauw-Gillet, Marie-Claire, Das, Krishna
• Other Authors: MARE - Centre Interfacultaire de Recherches en Océanologie - ULiège
• Format: Article in Journal/Newspaper
• Language: English
• Published: Elsevier Science 2013
• Subjects: marine mammals; pollutants; in vitro; Phoca vitulina; blood; contaminants; lymphoproliferation; immune parameters; immunotoxicology; Life sciences; Aquatic sciences & oceanology; Environmental sciences & ecology; Sciences du vivant; Sciences aquatiques & océanologie; Sciences de l’environnement & écologie
• Online Access: https://orbi.uliege.be/handle/2268/156095; https://orbi.uliege.be/bitstream/2268/156095/1/2013%20Aquat%20Tox%20142-3%20p210%20Dupont.pdf; https://doi.org/10.1016/j.aquatox.2013.08.014

peer reviewed tIn vitro culture of peripheral blood leucocytes (PBLs) is currently used in toxicological studies of marinemammals. However, blood cells of wild individuals are exposed in vivo to environmental contaminantsbefore being isolated and exposed to contaminants in vitro. The aim of this study was to highlightpotential relationships between blood contaminant levels and in vitro peripheral blood lymphocyteproliferation in free-ranging adult harbour seals (Phoca vitulina) from the North Sea. Blood samplesof 18 individuals were analyzed for trace elements (Fe, Zn, Se, Cu, Hg, Pb, Cd) and persistent organiccontaminants and metabolites ( PCBs, HO-PCBs, PBDEs, 2-MeO-BDE68 and 6-MeO-BDE47, DDXs,hexachlorobenzene, oxychlordane, trans-nonachlor, pentachlorophenol and tribromoanisole). The samesamples were used to determine the haematology profiles, cell numbers and viability, as well as thein vitro ConA-induced lymphocyte proliferation expressed as a stimulation index (SI). Correlation tests(Bravais-Pearson) and Principal Component Analysis with multiple regression revealed no statisticallysignificant relationship between the lymphocyte SI and the contaminants studied. However, the numberof lymphocytes per millilitre of whole blood appeared to be negatively correlated to pentachlorophenol(r = −0.63, p = 0.005). In adult harbour seals, the interindividual variations of in vitro lymphocyte pro-liferation did not appear to be directly linked to pollutant levels present in the blood, and it is likelythat other factors such as age, life history, or physiological parameters have an influence. In a generalmanner, experiments with in vitro immune cell cultures of wild marine mammals should be designed soas to minimize confounding factors in which case they remain a valuable tool to study pollutant effectsin vitro.