Monday, June 22, 2020

Dr. Eric Vivier: Association of COVID-19 inflammation with activation of the C5a-C5aR1 axis

9:00 AM to 10:00 AM

Eric Vivier is a professor of immunology at Aix-Marseille and hospital practitioner at Marseille Public University Hospital. He is also Chief Scientific Officer at Innate Pharma and coordinator of the Marseille Immunopôle cluster. He is also currently working at the Centre d’Immunologie de Marseille-Luminy (Ciml), being the director from 2008 to 2017.

Vivier has made contributions to the understanding of the molecular basis of the ontogeny, function, and therapeutic manipulation of natural killer (NK) cells, and the identification of innate lymphoid cells (ILCs) in mice and humans. His research has had a profound influence on the field of innate immunology.

His early work determined the mode of action of the inhibitory MHC class I receptors expressed on NK cells and extended the concept of ITIM-bearing molecules to multiple cell types and multiple biologic functions. In parallel, his group identified the ITAM-bearing polypeptide, KARAP/DAP12/Tyrobp.

These studies on NK cells led to the involvement of the Vivier laboratory in the discovery of ILCs through the detection and characterization of the ILC3 cell subset in human and mouse intestine.

Eric Vivier provides a longitudinal analysis of immune responses, including immune cell phenotyping and assessments of the soluble factors present in the blood and broncho-alveolar lavage fluid (BALF) of patients at various stages of COVID-19 severity: paucisymptomatic, pneumonia and acute respiratory distress syndrome (ARDS).

He reports an increase in soluble C5a levels proportional to COVID-19 severity and high levels of C5aR1 expression in blood and pulmonary myeloid cells, supporting a role for the C5a-C5aR1 axis in the pathophysiology of ARDS.

Anti-C5aR1 therapeutic monoclonal antibodies (mAbs) prevented C5a-mediated human myeloid cell recruitment and activation, and inhibited acute lung injury (ALI) in human C5aR1 knockin mice.

These results support C5a-C5aR1 axis blockade as a means of limiting myeloid cell infiltration in damaged organs and preventing the excessive lung inflammation and endothelialitis associated with ARDS in COVID-19 patients.

This webinar will be moderated by Dr. Abdallah Badou, Professor of Immunology at the Faculty of Medicine and Pharmacy, University Hassan II of Casablanca, Morocco.