Clinical Trial Summary
As of March 25, 2020, 414,179 cases and 18,440 deaths secondary to Coronavirus 2019 disease
(COVID-19) have been reported worldwide. The unfavorable course of the patients is
characterized on the immunological level by an intense pro-inflammatory response which can go
as far as a cytokinic storm. This pandemic affects a naive world population from an
immunological point of view with respect to SARS-CoV-2 responsible for COVID-19. The
evolution is favorable without hospitalization in almost 85% of cases. Among patients
hospitalized for pneumonia, some will not require ventilatory support while others will need
intensive care. To date, two main types of unfavorable evolution have been described. The
first is a bi-phasic evolution beginning with a paucisymptomatic form which is worsened
secondarily with respiratory distress associated with a decrease in the viral load in the
airways. The second is associated with persistent high viral loads in the airways and
detection of the virus in the blood. These different clinical profiles could depend on the
quantitative and qualitative response of the innate immune system.
At the early stage of a viral infection the innate immunity is capable of detecting certain
conserved microbial patterns (PAMP, pathogen-associated molecular pattern) recognized by
receptors dedicated to these patterns (PRR, pattern recognition receptor). This process
allows to initiate the pro-inflammatory response via different signaling pathways.
Activating multiprotein complexes called inflammasomes, which cause pro-IL-1β and pro-IL-18
to be transformed into active pro-inflammatory cytokines are one of these pathways.
The central role of inflammasomes in the secretion of these pro-inflammatory cytokines
deserves an in-depth study of their activation during COVID-19, whereas the inadequate
inflammatory response appears to be the determining factor in the unfavorable development of
patients.
The objective of this project is to analyze the level of activation of the inflammasomes and
then to search for inactivating or activating mutations among the genes which code for the
proteins constituting the inflammasomes in Covid-19 patients. The identification of mutations
in patients with a serious clinical presentation or even death would be followed by
fundamental work by analyzing in a cellular model the impact of these mutations on the
secretion of IL-1β.