Effect of high and low virulent strains of Flavobacterium psychrophilum on oxidative activity of rainbow trout (Oncorhynchus mykiss) spleen macrophages

Objective: Effect of F. psychrophilum strains with different virulence on oxidative activity of rainbow trout spleen macrophages were studied, using chemiluminescence technique (CL). Method & Materials: Spleen macrophages were collected from rainbow trout. Luminol was used as chemiluminigenic probe. Phorbol myristate acetate (PMA) also was used as positive control activating agent of the respiratory burst and this significantly stimulated reactive oxygen species (ROS) production by normal macrophages. Spleen macrophages produced ROS upon stimulation with both bacterial strains. Results & Conclusion: Approximately threefold as much ROS production was induced by the high virulence strain compared to the low virulence strain. In order to determine the role of ROS in bacterial killing, the antibacterial effect of hydrogen peroxide (H2O2) was evaluated for both strains. The low virulence strain was killed approximately eleven times more by H2O2 compared to the high virulence strain. In conclusion, this study demonstrated the capacity of differing virulence strains of F. psychrophilum to stimulate spleen macrophages of rainbow trout. Moreover, significant differences between the strains in their capacity to stimulate the macrophages were observed

کلیدواژه ها:

Rainbow trout ، Flavobacterium psychrophilum ، Reactive oxygen species ، Chemiluminescence ، Macrophage