Phagocytosis as a biomarker of immunotoxicity in wildlife species exposed to environmental xenobiotics

In the present paper, we are reviewing experimental evidence demonstrating that phagocytic cells, such as macrophages, may be used as a biomarker of i mmunotoxicity in wildlife studies. We will first present data obtained afte r exposure in vitro with selected chemicals showing the comparative sensiti vity of phagocytic cells from different species. These results demonstrate that, at least for metals, each species produce a similar shaped dose-respo nse curve, although considerate interspecies sensitivity is evident. These results also demonstrate the sensitivity of the phagocytic activity, sugges ting indeed that this function could be used to monitor exposure to chemica ls. The similar shaped dose-response curves imply that mechanisms of action may also be similar. Furthermore, based on the relative speices sensitivit y, sentinel species could be selected for field monitoring. Such an approac h may also be useful to establish correction factors required to extrapolat e results between species. This sensitivity of the phagocytic activity of m acrophages will be further under controlled conditions in laboratory animal models. Finally, the reliability of this approach will be demonstrated usi ng case studies with wildlife species.