Cystic fibrosis: regulation of chronic infections

A bacterium with a strong adaptive capacity

The Pseudomonas aeruginosa bacterium has a strong adaptability to a large number of hostile environments. It can also quickly develop a resistance to antibiotics following chronic infections and become very virulent. This leads to a therapeutic impasse and represents a global health threat today.

The Pseudomonas aeruginosa bacterium is classified by the World Health Organization in the critical priority list of multi-resistant bacteria.

Controlling lung infection

The goal of Dr. Touqui and his team at the Institut Pasteur is to find an interesting therapeutic target for the control of pulmonary infection by Pseudomonas aeruginosa, one of the major causes of mortality in patients with cystic fibrosis. The virulence of this bacterium is enhanced by its ability to inject exotoxins directly into the host cell. A better understanding of the role and mode of action of exotoxins would allow a better understanding of how this bacterium settles in a long-term and irreversible manner in the airways of cystic fibrosis patients, but also of immunocompromised patients infected by the bacterium.

ExoY, a key to understanding Pseudomonas aeruginosa

The aim of this research project is to study in particular the exotoxin ExoY, one of the four exotoxins produced by Pseudomonas aeruginosa. Preliminary studies suggest that the exotoxin ExoY stimulates the cellular defense process - phagocytosis - of this bacteria. It may even have an inhibitory effect in inducing the process of self-destruction (apoptosis) of the cells that the bacteria attacks. The study of this exotoxin remains to be developed. Therefore this project aims to analyse the role of ExoY in:

• the regulation of the phagocytosis of Pseudomonas aeruginosa by white blood cells (macrophages) 
• the inflammatory response of human respiratory epithelial cells and macrophages 
• Pseudomonas aeruginosa-induced self-destruction (apoptosis) of human respiratory cells

How the Air Liquide Foundation is participating

The Air Liquide Foundation is contributing to the acquisition of the consumables necessary for the research project and the operating costs from 2021 to 2024. The project is monitored by an Air Liquide Medical Systems Expert.