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Respiratory Research
Published in: Respiratory Research 1/2022

Open Access 01-12-2022 | SARS-CoV-2 | Research

Plasma markers of COVID-19 severity: a pilot study

Authors: Julia Beimdiek, Sabina Janciauskiene, Sabine Wrenger, Sonja Volland, Adriana Rozy, Jan Fuge, Beata Olejnicka, Isabell Pink, Thomas Illig, Alexander Popov, Joanna Chorostowska, Falk F. R. Buettner, Tobias Welte

Published in: Respiratory Research | Issue 1/2022

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Abstract

Background

SARS-CoV-2 infected patients show heterogeneous clinical presentations ranging from mild symptoms to severe respiratory failure and death. Consequently, various markers reflect this wide spectrum of disease presentations.

Methods

Our pilot cohort included moderate (n = 10) and severe (n = 10) COVID-19 patients, and 10 healthy controls. We determined plasma levels of nine acute phase proteins (APPs) by nephelometry, and full-length (M65), caspase-cleaved (M30) cytokeratin 18, and ADAMTS13 (a disintegrin-like and metalloprotease with thrombospondin type-1 motif 13) by ELISA. In addition, we examined whole plasma N-glycosylation by capillary gel electrophoresis coupled to laser-induced fluorescence detection (CGE-LIF).

Results

When compared to controls, COVID-19 patients had significantly lower concentrations of ADAMTS13 and albumin (ALB) but higher M30, M65, α1-acid glycoprotein (AGP), α1-antitrypsin (AAT), ceruloplasmin (CP), haptoglobin (HP), and high-sensitivity C-reactive protein (hs-CRP). The concentrations of α1-antichymotrypsin (ACT), α2-macroglobulin (A2MG) and serum amyloid A (SAA) proteins did not differ. We found significantly higher levels of AAT and M65 but lower ALB in severe compared to moderate COVID-19 patients. N-glycan analysis of the serum proteome revealed increased levels of oligomannose- and sialylated di-antennary glycans and decreased non-sialylated di-antennary glycan A2G2 in COVID-19 patients compared to controls.

Conclusions

COVID-19-associated changes in levels and N-glycosylation of specific plasma proteins highlight complexity of inflammatory process and grant further investigations.
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Metadata
Title
Plasma markers of COVID-19 severity: a pilot study
Authors
Julia Beimdiek
Sabina Janciauskiene
Sabine Wrenger
Sonja Volland
Adriana Rozy
Jan Fuge
Beata Olejnicka
Isabell Pink
Thomas Illig
Alexander Popov
Joanna Chorostowska
Falk F. R. Buettner
Tobias Welte
Publication date
01-12-2022
Publisher
BioMed Central
Published in
Respiratory Research / Issue 1/2022
Electronic ISSN: 1465-993X
DOI
https://doi.org/10.1186/s12931-022-02272-7

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