Flow Cytometric Analysis of In Vitro Cytotoxicity of Cadmium in Haemocytes from the Tiger Shrimp, Penaeus monodon

This study investigated the toxic effects of cadmium on viability, reactive oxygen species (ROS) production and non-specific esterase activity of Penaeus monodon haemocytes in vitro, using a flow cytometric assay. After 6 h in vitro exposure with 10−9–10−3 M Cd2+, cell viability, ROS production and esterase activity of haemocytes from P. monodon were determined. Results showed that at the lowest exposures (10−9–10−6 M), Cd2+ induced no effect on cell viability, ROS production and esterase activity. At a higher level (10−5 M) of exposure, production of ROS was stimulated while Cd2+ had no effect on cell viability and esterase activity. At the two highest concentrations (10−4 and 10−3 M), Cd2+ caused increased ROS production, cell death and inhibited esterase activity. These results showed a relationship between Cd2+ exposure dose and its cytotoxicity on shrimp haemocytes. Cadmium was cytotoxic and immunotoxic for P. monodon haemocytes in vitro when the dose reached 10−4 M. The study also suggested that flow cytometry could be used as a tool for cytotoxic research of aquatic contamination on shrimp.