Immunotoxic effects of triclosan in the clam Ruditapes philippinarum

Abstract

The effects of Triclosan (TCS) on the immune parameters of the clam Ruditapes philippinarum were investigated after a 7-day exposure to sublethal TCS concentrations (300, 600, and 900 ng l(-1)). Hemocytes from controls and exposed clams were collected, and the effects of TCS on total hemocyte count (THC), hemocyte diameter and volume, uptake of the vital dye Neutral Red (an indicator of pinocytosis), lysozyme activity, and proliferation were evaluated. The cytotoxicity, which was evaluated using the lactate dehydrogenase assay, and the capability of TCS to induce DNA fragmentation, which indicated apoptosis, were also investigated. The exposure of clams to all tested TCS concentrations significantly decreased THC, whereas the highest tested TCS concentration significantly reduced the diameter and volume of hemocytes. TCS negatively affected pinocytosis and the proliferation of hemocytes, but it did not alter hemocyte lysozyme activity. TCS exerted cytotoxic effects and induced DNA fragmentation in hemocytes of R. philippinarum. Overall, these results suggest a relationship between TCS exposure and changes in the measured immune parameters and indicate immunosuppression in TCS-treated clams.

The cell cultures and the use of haemocytes from marine molluscs for ecotoxicology assessment

“…Those statements were reviewed by Hine (1999) who suggested, in the absence of granuloblasts, a model with only one precursor cell type giving rise to hyalinocytes which further mature into granulocytes. Granules were never observed in blast-like cells from disk abalone, spiny top shell (Donaghy et al 2010), and V. philippinarum (Cima et al 2000;Matozzo et al 2011) supporting the hypothesis presented by Hine (1999). …”

“…Immunotoxic effects of environmental exposure to chemical contaminants could be evaluated by monitoring cellular immune parameters of sentinel species (Wong et al 1992). During the last decade, in vitro approaches were used to study physiological processes (Lebel et al 1996;Poncet et al 2000;Serpentini et al 2000;Riinkevich 2005; Auzoux-Bordenave and Domart-Coulon 2010) and the effects of pollutants (Domart-Coulon et al 2000;Canesi et al 2007a;Binelli et al 2009;Matozzo et al 2011). In fact, in vitro approaches are very useful, sensitive and selective for the detection, evaluation and monitoring of anthropogenic contaminants in aquatic environments.…”

The nonsteroidal anti-inflammatory drug, ibuprofen, affects the immune parameters in the clam Ruditapes philippinarum

“…The cationic probe NR was used to evaluate the capability of haemocytes to perform pinocytosis (Cajaraville et al, 1996;Matozzo et al, 2002Matozzo et al, , 2012. Pooled haemolymph (500 mL) from both untreated (controls) clams and clams treated with IBU was centrifuged at 780Â g for 10 min.…”

“…A commercial kit (Cytotoxicity Detection Kit, Roche) was used to assess IBU-induced cell damage. The assay used in this study has previously been validated (Matozzo et al, 2012).…”

“…In this study, the DNA fragments of apoptotic haemocytes were determined using a commercial kit (Cell Death Detection ELISA, Roche) and according to the manufacturer's instructions. This assay has already been validated in our recent study (Matozzo et al, 2012). A final volume of 500 mL of pooled haemolymph was used.…”