CiCXCL14 Exhibits Broad-Spectrum Bactericidal Activity and Protects Grass Carp Against Aeromonas hydrophila Infection

Abstract

Simple Summary Bacterial diseases are a major challenge in aquaculture, creating an urgent need for new disease-control strategies. In this study, we investigated the role of a natural immune protein, CXCL14, from grass carp in protecting fish against bacterial infections. We found that this protein was highly expressed in immune-related tissues and was upregulated after bacterial challenge. Recombinant CXCL14 showed broad-spectrum antibacterial activity against several important fish pathogens and protected grass carp by reducing bacterial burdens and improving survival after infection. Laboratory experiments also showed that the protein disrupted bacterial membranes and interacted with purified bacterial DNA in vitro. These findings improve our understanding of the antibacterial function of fish CXCL14 and provide a basis for future studies on its potential application in aquaculture.