Antiviral activity of cathelicidin 5, a peptide from Alligator sinensis, against WSSV in caridean shrimp Exopalaemon modestus

White spot disease caused by white spot syndrome virus (WSSV) is responsible for harming shrimp aquaculture industry and results in a pandemic throughout the world. Cathelicidin 5 treatment enhanced immune parameters including antioxidant enzyme activity and immune-related genes expression in shrimp Exopalaemon modestus. Shrimp treated with cathelicidin 5 and inoculated with white spot syndrome virus (WSSV) exhibited a significantly lower mortality rate and lower viral VP28 amplification and expression than control. This study addresses the role of cathelicidin 5 in immune stimulatory and antiviral activities that could protect E. modestus from WSSV infection. •There is no Cytotoxicity of cathelicidin 5 in vitro and in vivo.•Cathelicidin 5 could inhibit WSSV infection in vivo.•Cathelicidin 5 could protect hepatopancreas during WSSV challenge.•Cathelicidin 5 could increase caridean shrimp antioxidant enzyme activity.•Cathelicidin 5 could up-regulate caridean shrimp immune-related genes expression.