Circulating Calprotectin as a Biomarker of COVID-19 Severity

Expert Rev Clin Immunol. 2021 May;17(5):431-443. doi: 10.1080/1744666X.2021.1905526. Epub 2021 Apr 13.

Abstract

Introduction: Coronavirus disease 2019 (COVID-19) is an infectious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Although demographic and clinical parameters such as sex, age, comorbidities, genetic background and various biomarkers have been identified as risk factors, there is an unmet need to predict the risk and onset of severe inflammatory disease leading to poor clinical outcomes. In addition, very few mechanistic biomarkers are available to inform targeted treatment of severe (auto)-inflammatory conditions associated with COVID-19. Calprotectin, also known as S100A8/S100A9, MRP8/14 (Myeloid-Related Protein) or L1, is a heterodimer involved in neutrophil-related inflammatory processes. In COVID-19 patients, calprotectin levels were reported to be associated with poor clinical outcomes such as significantly reduced survival time, especially in patients with severe pulmonary disease.

Areas covered: Pubmed was searched using the following keywords: Calprotectin + COVID19, S100A8/A9 + COVID19, S100A8 + COVID-19, S100A9 + COVID-19, MRP8/14 + COVID19; L1 + COVID-19 between May 2020 and 8 March 2021. The results summarized in this review provide supporting evidence and propose future directions that define calprotectin as an important biomarker in COVID-19.

Expert opinion: Calprotectin represents a promising serological biomarker for the risk assessment of COVID-19 patients.

Keywords: COVID-19; calprotectin; inflammation; mrp8/14; s100a8/a9.

Publication types

  • Review
  • Video-Audio Media

MeSH terms

  • ATP-Binding Cassette Transporters* / blood
  • ATP-Binding Cassette Transporters* / immunology
  • Biomarkers / blood
  • COVID-19* / blood
  • COVID-19* / immunology
  • Calgranulin A* / blood
  • Calgranulin A* / immunology
  • Calgranulin B* / blood
  • Calgranulin B* / immunology
  • Humans
  • Severity of Illness Index*

Substances

  • ABCC11 protein, human
  • ATP-Binding Cassette Transporters
  • Biomarkers
  • Calgranulin A
  • Calgranulin B
  • S100A8 protein, human
  • S100A9 protein, human

Grants and funding

This paper was not funded.