Profiles of extracellular vesicle shutter proteins from Chlamys farreri stimulated by lipopolysaccharide

Extracellular vesicles (EVs) in aquatic animals can resist pathogen infection by delivering bioactive substances between cells. Chlamys farreri, as a commercial aquaculture species, was used as the research object in this study to explore the possible innate immune regulation mediated by EVs. In this study, data-independent acquisition (DIA) proteomics analysis was performed on EVs in the serum of C. farreri after lipopolysaccharide (LPS) stimulation. A total of 124 upregulated and 205 downregulated differentially expressed proteins (DEPs) were identified through comparative analysis. Related DEPs that may be involved in immune regulation in EVs were further screened, such as glucose-regulated protein 94 (HSP90B1), lysosome-associated membrane glycoprotein 1 (LAMP1), calreticulin (CALR), ras-related protein Rab-11 A (RAB11A), serine/arginine-rich splicing factor 1 (SRSF1), tumor susceptibility gene 101 protein (TSG101), and vesicle-associated membrane protein 3 (VAMP3). Enrichment analysis demonstrated that these DEPs were identified to be involved in the response to stimulus function, immune system process, and classical immune-related signaling pathways, such as the Toll-like receptor signaling pathway and RIG-I-like receptor signaling pathway. Further, PPI analysis was performed to predict the interactions between immune-related DEPs, which were mainly divided into proteins directly involved in immune regulation (such as HSP90B1, LAMP1, CALR, and RAB11A) and proteins indirectly involved in immune regulation by vesicle transport (such as TSG101, VAMP3, SNAP25, RAB14, and RAB2). These findings reveal that EVs play a central role in mediating innate immune regulation in C. farreri via cell communication under LPS stimulation, and are expected to provide important insights into disease-resistant breeding and aquaculture practices in shellfish.