Flagellin enhances shrimp antiviral immunity through the Shoc2/Erk/Stat/Ficolin pathway

Abstract

Pathogenic infections, particularly viral and bacterial infections (such as white spot syndrome virus and vibrio species), have emerged more frequently with the increase in aquaculture density and environmental stress, resulting in significant economic losses for the shrimp industry. Bacterial flagellin A (FlaA), a pathogen-associated molecular pattern, activates nuclear factor-kappa beta and mitogen activated protein kinase signaling pathways in mammals through the Toll-like receptor 5, thereby triggering an inflammatory response. This study is the first to demonstrate that FlaA regulates the expression of the antiviral molecule ficolin through the Shoc2/Erk/Stat pathway, thereby enhancing antiviral capacity in shrimp. Our results indicate that FlaA induces antibacterial molecules and activates antiviral molecules, showcasing broad-spectrum immune-activating potential. These findings advance our understanding of the role of FlaA in host immunity and offer valuable insights for developing immune-modulatory antiviral strategies in aquaculture.