title: Comparative analysis of hemocyte properties from Mytilus edulis desolationis and Aulacomya ater in the Kerguelen Islands.
abstract: The capability of bivalve molluscs to respond to environmental stresses largely depends upon their cellular immunity. Accordingly, shift in habitat conditions following thermal stress or exposure to pollutants may harm sensitive species differently, thereby modulating the biodiversity of a given ecosystem by favoring stress-tolerant species. Here, we have compared the sensitivity of hemocytes from Mytilus edulis desolationis (M. edulis desolationis) and Aulacomya ater (A. ater) to acute thermal stress and exposure to cadmium. The two subantarctic species are commonly found in the same habitat in the isolated Kerguelen archipelago. Our results showed that the phagocytic activity and viability of hemocytes from both species were equally sensitive to increasing concentrations of cadmium. However, although in vitro exposure to cadmium induced apoptosis in hemocytes of M. edulis desolationis and A. ater, flow cytometric analyses showed that the apoptotic profile of both species differed greatly when using Annexin V and YO-PRO-1 as apoptotic markers. We also found that the total hemocyte counts decreased strongly in A. ater but not in M. edulis desolationis following an acute thermal stress. Taken together, these results showed that stress responses differed significantly in hemocytes from both species. This suggests that the co-existence of both species may be at risk following exposure to pollutants and/or changes in temperature.
authors.affiliation: INRS-Institut Armand-Frappier, 531 Boul. des Prairies, Laval, Québec H7V 1B7, Canada.
authors.forename: France
authors.initials: F
authors.lastname: Caza
authors.affiliation: Université Reims Champagne-Ardenne, UMR-I 02 SEBIO Stress environnementaux et Biosurveillance des milieux aquatiques, Campus Moulin de la Housse, 51687 Reims, France.
authors.forename: Stéphane
authors.initials: S
authors.lastname: Betoulle
authors.affiliation: Laboratoire des Sciences de l'Environnement Marin, UMR CNRS 6539-LEMAR, Technopôle Brest-Iroise, 29280 Plouzane, France.
authors.forename: Michel
authors.initials: M
authors.lastname: Auffret
authors.affiliation: INRS-Institut Armand-Frappier, 531 Boul. des Prairies, Laval, Québec H7V 1B7, Canada.
authors.forename: Pauline
authors.initials: P
authors.lastname: Brousseau
authors.affiliation: INRS-Institut Armand-Frappier, 531 Boul. des Prairies, Laval, Québec H7V 1B7, Canada.
authors.forename: Michel
authors.initials: M
authors.lastname: Fournier
authors.affiliation: INRS-Institut Armand-Frappier, 531 Boul. des Prairies, Laval, Québec H7V 1B7, Canada. Electronic address: yves.st-pierre@iaf.inrs.ca.
authors.forename: Yves
authors.initials: Y
authors.lastname: St-Pierre
mesh_terms: D000818:Animals; D002104:Cadmium / Q000633:toxicity*; D005434:Flow Cytometry; D006434:Hemocytes / Q000187:drug effects / Q000502:physiology*; D007195:Indian Ocean Islands; D049879:Mytilidae / Q000187:drug effects / Q000502:physiology*; D049880:Mytilus edulis / Q000187:drug effects / Q000502:physiology; D013312:Stress, Physiological; D061350:Sympatry; D013696:Temperature; D014874:Water Pollutants, Chemical / Q000633:toxicity*
chemical_list: D014874:Water Pollutants, Chemical; D002104:Cadmium
keywords: Apoptosis; Cadmium; Flow cytometry; Hemocytes; Kerguelen; Phagocytosis