Jump to main content
Jump to site search

Issue 8, 2010
Previous Article Next Article

Immunocompetence and alterations in hepatic gene expression in rainbow trout exposed to CdS/CdTe quantum dots

Author affiliations

Abstract

Cadmium (Cd) tellurium quantum dots (QDs) are long-lived fluorescent nanocrystals that have the ability to produce potentially toxic reactive oxygen species at the surface of the nanoparticle and release toxic cadmium ions. The purpose of this study was to examine the sublethal effects of CdS/CdTe QDs and dissolved Cd on the immune system of rainbow trout. Changes in hepatic gene expression were also monitored to provide insight on the mode of action of both forms of cadmium. Oncorhynchus mykiss fish were exposed to increasing concentrations of CdS/CdTe or dissolved Cd (CdSO4) for 48 h at 15 °C. The anterior head kidney was analyzed for leukocyte count, viability and phagocytic activity. The livers were harvested and prepared for gene expression analysis using a DNA microarray comprised of 207 stress-related genes. An analysis of total Cd in the aquarium water revealed that the nominal concentrations corresponded well to the actual concentrations and that a small proportion (0.4%) of Cd in the QDs was found in the dissolved fraction. Exposure to QDs led to significant reductions in leukocyte counts, viability and both resting and active phagocytic activity. On a mass concentration basis, QDs were more potent than dissolved Cd in suppressing immunocompetence in rainbow trout. The analysis revealed that both forms of Cd were strong inducers of metallothionein and CP2K1 gene expressions, which are respectively involved in metal detoxification processes and xenobiotic transformation/inflammation conditions. The analysis revealed different modes of action for each form of Cd. For QDs, 25 genes specific to QDs and related to the immune endpoints were found. The genes were involved in inflammation, xenobiotic biotransformation and endocrine system (including the induction of vitellogenin and its receptor). The effect for dissolved Cd was narrower than for QDs, with 9 genes specific to dissolved Cd being strongly correlated with the observed effects on immunocompetence. The involved genes were binding and transport of various solutes (urea, sodium, potassium) and the complement system. The present study revealed that each form of Cd produced a different pattern of gene expression and lowered fish immunocompetence.

Graphical abstract: Immunocompetence and alterations in hepatic gene expression in rainbow trout exposed to CdS/CdTe quantum dots

Back to tab navigation

Publication details

The article was received on 02 Mar 2010, accepted on 28 Apr 2010 and first published on 01 Jul 2010


Article type: Paper
DOI: 10.1039/C0EM00031K
Citation: J. Environ. Monit., 2010,12, 1556-1565
  •   Request permissions

    Immunocompetence and alterations in hepatic gene expression in rainbow trout exposed to CdS/CdTe quantum dots

    F. Gagné, M. Fortier, L. Yu, H. L. Osachoff, R. C. Skirrow, G. van Aggelen, C. Gagnon and M. Fournier, J. Environ. Monit., 2010, 12, 1556
    DOI: 10.1039/C0EM00031K

Search articles by author

Spotlight

Advertisements