Proteomic analysis of salivary extracellular vesicles from COVID-19 patients reveals a specific anti-COVID-19 response protein signature

ABSTRACT: Saliva, a biofluid enriched in biological omic constituents, has emerged as a promising source for exosomal biomarkers due to its easy accessibility. Despite the understanding of the coronavirus disease-19 (COVID-19), the role of Salivary Extracellular Vesicles (sEVs) in COVID-19 remains poorly understood. Exploring the proteomic cargo of sEVs could prove valuable for diagnostic and prognostic purposes in assessing COVID-19. The proteomic cargo of sEVs from COVID-19 (+) subjects and their healthy close contacts (HCC) was explored. Nine COVID-19 positive (+) patients and eleven in-house close contact patients identified by real-time quantitative polymerase chain reaction (RT-qPCR) of nasopharyngeal swabs were included. In-house close contacts were defined as individuals with a negative RT-qPCR result sharing a residence with a confirmed COVID-19 case. sEVs were isolated by ultracentrifugation from unstimulated saliva samples, and subsequently characterized through nanoparticle tracking, transmission electron microscopy, and western-blot analyses. The proteomic cargo of sEVs was processed by LC-MS/MS. sEVs were morphologically compatible with EVs, with the presence of Syntenin-1 and CD81 EVs markers. The sEVs proteome showed 1,417 proteins: 1,288 in COVID-19 (+) cases and 1,382 in HCC. 35 proteins were found exclusively and 89 were more abundant in sEVs from COVID-19 (+) subjects. “Coronavirus disease response”, “complement and coagulation cascades”, and “PMN extracellular trap formation” were the most enriched KEGG pathways in COVID-19 (+) cases. The most represented biological processes were “Hemoglobin and haptoglobin binding” and “oxygen carrier activity”, and the best-denoted molecular functions were “regulated exocytosis and secretion” and “leucocyte and PMN mediated immunity”. We suggest that sEVs proteomic cargo in COVID-19 is related to immune response processes, oxygen transport, and antioxidant mechanisms. In contrast, in HCC, sEVs signature profiles are mainly associated with epithelial homeostasis.

INSTRUMENT(S): timsTOF Pro

ORGANISM(S): Homo Sapiens (human)

TISSUE(S): Saliva

SUBMITTER: Guillermo Nourdin  

LAB HEAD: Alejandra Chaparro

PROVIDER: PXD047446 | Pride | 2024-05-21

REPOSITORIES: Pride