A multi-omics investigation of the composition and function of extracellular vesicles along the temporal trajectory of COVID-19

Exosomes represent a subtype of extracellular vesicle that is released through retrograde transport and fusion of multivesicular bodies with the plasma membrane(1). Although no perfect methodologies currently exist for the high-throughput, unbiased isolation of pure plasma exosomes(2,3), investigation of exosome-enriched plasma fractions of extracellular vesicles can confer a glimpse into the endocytic pathway on a systems level. Here we conduct high-coverage lipidomics with an emphasis on sterols and oxysterols, and proteomic analyses of exosome-enriched extracellular vesicles (EVs hereafter) from patients at different temporal stages of COVID-19, including the presymptomatic, hyperinflammatory, resolution and convalescent phases. Our study highlights dysregulated raft lipid metabolism that underlies changes in EV lipid membrane anisotropy that alter the exosomal localization of presenilin-1 (PS-1) in the hyperinflammatory phase. We also show in vitro that EVs from different temporal phases trigger distinct metabolic and transcriptional responses in recipient cells, including in alveolar epithelial cells, which denote the primary site of infection, and liver hepatocytes, which represent a distal secondary site. In comparison to the hyperinflammatory phase, EVs from the resolution phase induce opposing effects on eukaryotic translation and Notch signalling. Our results provide insights into cellular lipid metabolism and inter-tissue crosstalk at different stages of COVID-19 and are a resource to increase our understanding of metabolic dysregulation in COVID-19.

Automated summary

This study analyzed exosome-enriched extracellular vesicles from patients at different stages of COVID-19, highlighting dysregulated lipid metabolism in the hyperinflammatory phase and distinct metabolic and transcriptional responses triggered by EVs from different temporal phases in recipient cells. The results provide insights into cellular lipid metabolism and inter-tissue crosstalk at different stages of COVID-19 and contribute to understanding metabolic dysregulation in COVID-19.