Study of Immune Response During SARS-CoV-2 Infection

Since March 2020, Europe has been facing the spread of Coronavirus disease 2019 (COVID-19), an emerging infectious disease of viral zoonosis type, caused by the coronavirus SARS-CoV-21. This virus is responsible for an epidemic in Wuhan in November 2019 and a pandemic in March 2020. The mode of transmission, both respiratory and by contact, carried by microdroplets emitted by an infected person and inhaled by a person nearby, induces a very high contagiousness rate2. In the majority of cases, CoV-2-SARS infection is not very symptomatic, but some evolve into severe forms, particularly in frail people: elderly subjects, those affected by chronic diseases (diabetes, obesity or cancer) or those undergoing immunosuppressive treatments. There is still little information on the reasons why some will develop a severe form while others will remain asymptomatic. The immune response is little studied in this context.

Functional study of the cellular immune response has shown its interest in predicting the risk of infection in different cohorts, particularly in renal insufficiency subjects awaiting transplantation with an over-risk of developing an infection within a year in patients with a low level of gamma interferon (INFγ: main anti-viral cytokine) after non-specific stimulation of T lymphocytes.

A study published the clinical characteristics of 41 patients infected with coronavirus at the Huanan seafood market (first contact cases). Despite a similar clinical symptomatology: cough (76%) and fever (98%), some patients required rapid ventilatory assistance. These patients had an increased production of inflammatory cytokines: IL2, IL7, IL10, GSCF, IP10, MCP1, MIP1A, and TNFα3.

Here, the objective is to identify cytokine profiles in subjects exposed to or infected with SARS-CoV-2 that can predict their risk of developing a severe pauci-symptomatic form at the time of exposure or during the development of a severe form. the team believes that the immune response to this infection is a major factor in the risk of developing an asymptomatic infection, a flu-like symptomatology or a respiratory failure syndrome (ARDS).3,4 The team believes that the immune response to this infection is a major factor in the risk of developing an asymptomatic infection, a flu-like symptomatology or a respiratory failure syndrome (ARDS). The team thus wishes to better direct patients to appropriate care structures to optimise the care pathway (ambulatory, infectiology, intensive care), respirators and number of beds so as not to overload the staff) and to enable treatments to be personalised and adapted as best as possible: corticosteroids, immunomodulators, antivirals.

The study will be based on 2 axes: a first clinical axis (i) and a cellular axis (ii).