Webinar: Do Human Endogenous Retroviruses (HERVs) Contribute to COVID-19 Immunopathology?
Human Endogenous Retroviruses (HERVs) have been described as genetic elements present in the human genome arising from the integration and ancestral fixing of proviruses in our genome. HERVs today represent 8% of the human genome (against 3% for the coding genome) but the vast majority of them are transcriptionally inactive. However, under certain conditions, some of these sequences can be awakened and play a pathogenic role. Their activation has increasingly been found to be associated with various diseases including multiple sclerosis, type 1 diabetes, cancers,… which are all underlying diseases in patients developing severe forms of COVID-19. Several studies confirmed that the immunopathogenic envelope protein of HERV family W (HERV-W ENV) is involved in inflammatory and neurological diseases (reviewed in 2). Moreover, HERV-W was shown to be directly activated by exogenous viruses (including SARS-CoV-2) with various outcomes depending on triggering viruses and susceptible cells or tissues.
We demonstrate for the first time an elevated expression of the HERV-W ENV protein in the blood cells and sera of COVID-19 (detection on Simple Western™ capillary based immunoassay) patients compared to that of healthy donors and its correlation with markers of inflammation including cytokines expression (performed on Ella™ with the COVID-19 Simple Plex cytokine storm panel), T cell differentiation and exhaustion, and the IgGs anti-SARS-CoV-2 serology (performed on Simple Western using the SARS-CoV-2 Multi-Antigen Serology Module). Based on the potential early reactivation by SARS-CoV-2, we propose HERV-W ENV protein as a contributing factor to the immunopathology of COVID-19.
In addition, lymphopenia observed in COVID-19 patients causes an absence of IgG production in a significant number of patients inducing false negatives during SARS-CoV-2 serology. In order to limit these false negatives, and obtain additional results on COVID-19 physiopathology, we are currently developing a detection system for anti-SARS-CoV-2 IgMs for use on Simple Western which could complement the SARS-CoV-2 Multi-Antigen Serology Module which is based solely on the detection of IgGs.