2.5. Reactive oxygen species (ROS) production
To monitor the level of ROS, the cell-permeant probe 2′,7′-dichlorofluorescein diacetate (DCFH-DA, Sigma) was used as described
previously (Xian et al., 2010). A volume of 200μL haemocyte suspension was incubated with 10μM DCFH-DA for 30 min at room temperature in the dark. Then thefluorescence of cells was recorded on FL1
detector offlow cytometer. ROS production was expressed as mean
fluorescence of DCF.