Characterization and evaluation of sCD163 potential as severity biomarker in SARS-CoV-2 infection

• Grant number: 20/13120-8
• Support Opportunities: Scholarships in Brazil - Master
• Effective date (Start): April 01, 2021
• Effective date (End): January 31, 2023
• Field of knowledge: Biological Sciences - Immunology - Cellular Immunology
• Principal Investigator: Larissa Dias da Cunha
• Grantee: Marlon Fortes Rocha
• Host Institution: Faculdade de Medicina de Ribeirão Preto (FMRP). Universidade de São Paulo (USP). Ribeirão Preto , SP, Brazil
• Associated research grant: 18/25559-4 - Molecular mechanisms of LC3-associated phagocytosis and its role in macrophage function, AP.JP

Abstract

SARS-CoV-2 infected patients that become critically ill develop symptoms similar to Macrophage Activation Syndrome (MAS): hypercytokinemia, increased LDH and markers of tissue damage - and thay may progress to multiple organs failure. Recent publications about COVID-19 immunopathology suggest a dysfunctional immune system: patients with acute leukopenia, with T cells lymphopenia and neutrophilia associated to presence of immature neutrophils. In the monophagocytic system, the exacerbated activation of monocytes/macrophages may contribute to the morbidity and mortality in the patients. Our analysis of COVID-19 patients indicate dysfunctional monocytes with reduction of resolution related monocytes, increase in inflammatory monocytes and lower levels of HLA-DR on the cell surface. Moreover, we observe higher CD163 expression on the membrane that correlates directly with the rise of LDH serum levels. CD163 is an exclusive macrophage/monocyte markers and its high expression is associated with MAS. The soluble form (sCD163) has been described as severity biomarker for this syndrome in multiple contexts of chronic inflammation. Our hypothesis is that sCD163 can act as a prognostic biomarker for the COVID-19 immunopathologic evolution associate with exaggerated macrophage and monocyte activation in severe patients. Thus, we propose to investigate the sCD163 potential as severe prognostic biomarker in patients infected with SARS-CoV-2. (AU)