|Field contamination of the starfish Asterias rubens by metals. Part 2: effects on cellular immunity|Coteur, G.; Gillan, D.; Joly, G.; Pernet, P.; Dubois, P. (2003). Field contamination of the starfish Asterias rubens by metals. Part 2: effects on cellular immunity. Environ. Toxicol. Chem. 22(9): 2145-2151. dx.doi.org/10.1897/02-490
In: Environmental Toxicology and Chemistry. Setac Press: New York. ISSN 0730-7268, more
cellular immunity; heavy metals; amoebocytes; Asterias rubens;echinoderms
To study the effects of matals on starfish in field conditions, immune responses measured in starfish from natural populations along a metal pollution gradient (long-term contamination) and in starfish that were transferred up the gradient (short-term contamination). Coelomic amoebocyte concentration (CAC) and production oh reactive oxygen species (ROS) by amoebocytes were measured in two varieties oh Asterias rubens occurring in the fjord: The black variety which lives only in the low salinity upper waters (22-26‰) and the red variety which live both in the upper layer and in the deeper layer characteruzed by a salinity close to that oh seawater (30‰). The studied immune response were stimulated in starfish living along the metal pollution gradient according to the contamination oh these starfish by cadmium. However, the sensitivity oh these responses toward metals appeared to be strongly modulated by the salinity stress. In red starfish living at 30‰ and transferred up the contamination gradient, the immune responses were inhibited and closely hollowed the short-term accumulation oh metals in the animal organs. Starfish transferred down the gradient did not recover normal immune responses in the short-term and appeared highly sensitive to caging stress. It is suggested that the impact oh metals on the immune responses oh A. rubens in field conditions occurs in three phases. Short-term inhibitory effects are exerted by a direct action of metals on the immune cells and are followed by a recovery due to the induction oh protective mechanisms. Eventually, when these mechanisms are overwhelmed by a long-term contamination, indirect and durable stimulatory effects on the immune responses appear due to a global disruption oh the animal physiology.