A preliminary investigation of immune-related components in the carapace of Litopenaeus vannamei

The carapace of arthropods not only served as a protective exoskeleton, but also performed a wide range of physiological and biochemical functions. In this study, we preliminarily investigated the protein and metabolite components of the carapace of Pacific white shrimp Litopenaeus vannamei and their biological functions, focusing on their roles in the process of innate immunity. The structure of the carapace was analyzed by scanning electron microscopy (SEM), while quantitative proteomics and metabolomics were used to investigate its components and functions. A total of 1,108 proteins and 725 metabolites were identified in the carapace of L. vannamei, including 69 immune-related proteins and 9 immune-related metabolites. These diverse components are involved in metabolism, environmental responses and immunity, enriched in pathways such as Toll-like receptor, IMD, NOD-like receptor and melanogenesis, demonstrating the shrimp's ability to combat pathogens through both active and passive immune mechanisms. In conclusion, this study demonstrated that shrimp carapace plays an essential role in the innate immune process.