Proteomic and metabolomic profiling of plasma uncovers immune responses
in patients with Long COVID-19
Abstract
Long COVID is an often-debilitating condition with severe, multisystem
symptoms that can persist for weeks or months and increase the risk of
various diseases. Currently, there is a lack of diagnostic tools for
Long COVID in clinical practice. Therefore, this study utilizes plasma
proteomics and metabolomics technologies to understand the molecular
profile and pathophysiological mechanisms of Long COVID, providing
clinical evidence for the development of potential biomarkers. This
study included three age- and gender-matched cohorts: healthy controls
(n=18), COVID-19 recovered patients (n=17), and Long COVID patients
(n=15). The proteomics results revealed significant differences in
proteins between Long COVID-19 patients and COVID-19 recovered patients,
with dysregulation mainly focused on pathways such as coagulation,
platelets, complement cascade reactions, GPCR cell signal transduction,
and substance transport, which can participate in regulating immune
responses, inflammation, and tissue vascular repair. Metabolomics
results showed that Long COVID patients and COVID-19 recovered patients
have similar metabolic disorders, mainly involving dysregulation in
lipid metabolites and fatty acid metabolism, such as
glycerophospholipids, sphingolipid metabolism, and arachidonic acid
metabolism processes. In summary, our study results indicate significant
protein dysregulation and metabolic abnormalities in the plasma of Long
COVID patients, leading to coagulation dysfunction, impaired energy
metabolism, and chronic immune dysregulation, which are more pronounced
than in COVID-19 recovered patients.