Modulation of SARS-CoV-2 cell entry – COVENTRY

There is indeed an urgent need to develop treatments for COVID-19. COVID-19 pandemic is due to the SARS-CoV-2 coronavirus that infects human cells through binding of its spike S protein to cell receptors including the ACE2 protein. The entry of virus into the cell after binding to its receptor is still not clearly deciphered. It is expected that preventing SARS-CoV-2 cell entry and intracellular trafficking may prevent or revert the progression of COVID-19.
The goal of this project is to identify drugs preventing or decreasing SARS-CoV-2 cell entry and trafficking. To shorten clinical applications, drugs already approved for human usage will be screened in view of repurposing towards COVID-19 treatment.
The ubiquitously expressed mechanoenzyme dynamin (DNM2) is the key regulator of endocytosis and membrane trafficking as it mediates the fission of membrane to promote vesicle release from the plasma membrane and from other organelles. SARS-CoV-2 enter into cell through both dynamin-dependent endocytosis and direct membrane fusion, then traffic and mature inside the cell partly in vesicles. DNM2 inhibition is thus a promising target and was shown to prevent cell entry of a plethora of viruses including coronoviruses.
We previously identified FDA-approved drugs that inhibit DNM2 GTPase activity in vitro, highlighting candidate drugs that will now be tested for their effect on SARS-CoV-2 cell entry. We also validated Spike protein-typed MLV pseudovirus bearing the common G614 variant and expressing GFP or luciferase as a surogate to assess SARS-CoV-2 cell entry and trafficking. To assess the efficacy of selected FDA-approved drugs to impair SARS-CoV-2 cell entry the project includes several workpackages :
- WP1. SARS-CoV-2 pseudovirus production expressing GFP or luciferase.
- WP2. In cellulo drug medium throughput screening for reducing SARS-CoV-2 pseudovirus entry, using BGM and Vero E6 cells that are permissive to SARS-CoV-2 infection. Cell toxicity and inhibition efficacy (IC50) will be determined.
- WP3. Mechanism of inhibition, and dependence on dynamin.
- WP4. Validation in human cells and determination of IC50.
This work should lead to the validation of one or several FDA-approved drugs for the inhibition of SARS-CoV-2 cell entry in a cellular assay. Indeed, drugs have simple chemical structures that can have several biomolecule targets. Drug repurposing is advantageous as their clinical effects, potential toxicity and production are already mastered. Depending on the drug, massive amount of compound may be already available for use. Drugs that could decrease SARS-CoV-2 cell entry should reduce the unfavorable course and potentially the contagiousness of COVID-19. They could be used in infected individuals to better prevent the development of severe forms, and potentially as a prophylaxis on a short term period. Clinical trials for validation in Human and therapeutic usage could be envisaged by the end of this project (9 mo).