Proteins associated with neutrophil degranulation are upregulated in nasopharyngeal swabs from SARS-CoV-2 patients

PLoS One. 2020 Oct 20;15(10):e0240012. doi: 10.1371/journal.pone.0240012. eCollection 2020.


COVID-19 or severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) appeared throughout the World and currently affected more than 9 million people and caused the death of around 470,000 patients. The novel strain of the coronavirus disease is transmittable at a devastating rate with a high rate of severe hospitalization even more so for the elderly population. Naso-oro-pharyngeal swab samples as the first step towards detecting suspected infection of SARS-CoV-2 provides a non-invasive method for PCR testing at a high confidence rate. Furthermore, proteomics analysis of PCR positive and negative naso-oropharyngeal samples provides information on the molecular level which highlights disease pathology. Samples from 15 PCR positive cases and 15 PCR negative cases were analyzed with nanoLC-MS/MS to identify the differentially expressed proteins. Proteomic analyses identified 207 proteins across the sample set and 17 of them were statistically significant. Protein-protein interaction analyses emphasized pathways like Neutrophil degranulation, Innate Immune System, Antimicrobial Peptides. Neutrophil Elastase (ELANE), Azurocidin (AZU1), Myeloperoxidase (MPO), Myeloblastin (PRTN3), Cathepsin G (CTSG) and Transcobalamine-1 (TCN1) were found to be significantly altered in naso-oropharyngeal samples of SARS-CoV-2 patients. The identified proteins are linked to alteration in the innate immune system specifically via neutrophil degranulation and NETosis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Betacoronavirus / genetics*
  • COVID-19
  • Cell Degranulation / immunology*
  • Chromatography, Liquid / methods
  • Coronavirus Infections / immunology*
  • Coronavirus Infections / virology
  • Female
  • Humans
  • Male
  • Middle Aged
  • Nasopharynx / virology*
  • Neutrophil Activation / immunology*
  • Neutrophils / immunology*
  • Pandemics
  • Pneumonia, Viral / immunology*
  • Pneumonia, Viral / virology
  • Protein Interaction Maps
  • Proteome*
  • Proteomics / methods
  • Real-Time Polymerase Chain Reaction
  • SARS-CoV-2
  • Tandem Mass Spectrometry / methods
  • Up-Regulation*
  • Young Adult


  • Proteome

Grants and funding

Acibadem Labmed Clinical Laboratory provided support for this study in the form of salaries for MBT, BS, CK, HNC, and IU. The specific roles of these authors are articulated in the ‘author contributions’ section. Data acquisition was also conducted in Acibadem Labmed Clinical Laboratory’s proteomics facility. The funders had no further role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. The authors received no other specific funding for this work.