Comparison of antiviral efficiency of immune responses in shrimp.

The antiviral effectiveness of three major immune responses including phagocytosis, apoptosis and proPO system in the shrimp Marsupenaeus japonicus was characterized. It was found that the suppression of apoptosis and phagocytosis in vivo by their corresponding inhibitors resulted in the increase of white spot syndrome virus (WSSV) copies and shrimp mortality, whereas the inhibition of phenol oxidase generated the least influence on WSSV infection and shrimp mortality. These results suggest that apoptosis and phagocytosis were the essential immune responses to protect shrimp from virus infection, while the phenol-oxidase-dependent proPO system plays a comparatively minor role in antiviral defense of shrimp.