Sepsis Biomarker Identification in Extracellular Vesicles of Dogs

Sepsis, the organ dysfunction triggered as a consequence of deleterious inflammatory host response to infection, has a 26% mortality rate in humans. However, there is a lack of reliable biomarkers for its accurate diagnosis. Extracellular vesicles (EVs) are small particles naturally released from the cells with promising applications in diagnosis and disease monitoring. This Project aims to evaluate salivary and serum EVs as sources of novel biomarkers in a naturally occurring model of sepsis using a multidisciplinary approach. For this, canine pyometra, a naturally occurring animal model for human sepsis, will be used. Different isolation methods for EVs and their subpopulations will be evaluated, and the most feasible will be selected. Isolated EVs will be characterized using proteomics, metabolomics, and biochemical analyses. Last, the quantity and characterization of EVs will be compared between dogs meeting sepsis criteria and those obtained from healthy individuals and animals with inflammation. This would point out different biomarkers of sepsis to be further evaluated.The results of this Project would help improve sepsis diagnostics, which can highly increase patient survival and promote adequate use of antibiotics, ultimately fighting against antimicrobial resistance. Plus, it will support using saliva as a non-invasive sample for sepsis diagnosis. Last, it is expected that the sepsis biomarkers identified in this Project could be extrapolated to other species, including humans.