In a recent study, scientists discovered specific molecular markers in the blood that predict serious outcomes from SARS-CoV-2 coronavirus infection. The results of this study expand the understanding of the pathophysiology and clinical progression of COVID-19 and have the potential to identify early in the infectious process which individuals are most likely to develop serious disease and require hospitalization.
In addition to pneumonia and septic syndrome, a small percentage of patients also experience severe gastrointestinal and/or cardiovascular symptoms and neurological symptoms after SARS-COV-2 infection.
This study used a multi-omics approach to integrate data from different omics disciplines, including cutting-edge transcriptomic, proteomic and metabolomic technologies, to identify significantly associated molecular alterations in COVID-19 patients (especially critically ill patients). This work evaluated data from 83 patients in three groups, including 16 severe cases, 50 mild cases and 17 virus-free healthy controls.
Serial blood and throat swab samples were collected from all participants and determined whether COVID-19 pathophysiology was related to specific molecular changes, with a total of 23,373 expressed genes, 9,439 proteins, 327 metabolites and 769 extracellular RNA molecule fragments.
Between mild and severe cases, there are significant differences between various immune markers (e.g., type 1 interferons and inflammatory cytokines), the latter being elevated in the latter, which shows a robust T cell response that may help prevent disease progression.
In addition, there was a significant correlation between multi-omics data and classical diagnostic blood or biochemical parameters. This is particularly reflected in the proteomic analysis, where tricarboxylic acid cycle (TCA) and glycolytic pathways were significantly downregulated in mild and severe patients compared to healthy controls. In contrast, in patients with COVID-19, host defense pathways (e.g., T-cell receptor signaling pathways) express elevated activity.
Another potentially valuable finding for future clinical use is the association between viral load and disease prognosis in patients with severe COVID-19. Unfortunately, six severely symptomatic patients died, and their SARS-CoV-2 RNA load obtained by sampling in the throat before admission was significantly higher than that of survivors. The notable finding here is that proteins involved in antiviral processes, including T-cell and B-cell receptor signaling pathways, are positively correlated with viral load changes in surviving severe patients.
Introduction to biomarker
Biomarker refers to indicators that can be used to indicate physiological processes, pathological processes, and pharmacological responses to therapeutic measures. Biomarkers can sensitively reflect disease states and can be used for disease screening, disease diagnosis, predictive drug adverse reactions, and drug dose response studies, as well as prognostic indicators for disease treatment.