Benoît Chassaing : Tracking the Intestinal Microbiota "Invaders"

Inserm Research Officer Benoît Chassaing has recently created his Mucosal Microbiota in Chronic Inflammatory Diseases team at Institut Cochin (Paris) – an opportunity that he owes to European Research Council funding. A world of intestinal bacteria awaits him, particularly those implicated in the development of inflammatory and metabolic diseases.

Benoît Chassaing is tracking the billions of bacteria present in our intestines. His aim? To describe their identity, functioning, interactions with the rest of the body, and how they impact our health. A mammoth task! It all began with his PhD, which he did in the Microbes, Intestine, Inflammation and Host Susceptibility unit* in Clermont Ferrand, and obtained in 2011. With his thesis supervisor and molecular biology professor Arlette Darfeuille-Michaud, he studied certain strains of bacteria implicated in intestinal inflammation. "Her enthusiasm for research was infectious, he jokes. I caught my passion for the subject from her". And that was how Chassaing began to develop an interest in the intestinal microbiota – the communities of microorganisms that colonize our intestines.

His next step took him to the Institute for Biomedical Sciences of Georgia State University (Atlanta, USA), to do a postdoctoral fellowship dedicated to studying the microbiota under the leadership of Andrew Gewirtz. "It was a very rewarding experience and really broadened my expertise in the field. We developed new tools and analysis techniques for studying the intestinal microbiota", he explains. He studied its regulation and particularly the genetic and environmental factors that affect its make-up. He then decided to stay on for another four years as Assistant Professor, in order to develop his research independently. It was during that period that he discovered that the mucus layer covering the intestinal wall – which is meant to be sterile in order to isolate the rest of the body from the intestinal bacteria – can be colonized by certain bacteria that he has decided to call Invaders. And that is not all: their presence is linked to the development of chronic inflammatory diseases and metabolic deregulation, not just in animals but also in humans!

Chassaing then decided to pursue his investigations. He wanted to identify these Invaders that are capable of penetrating this forbidden territory, to understand how they do this and under what circumstances – in order to develop novel therapeutic approaches to prevent the presence of these harmful bacteria. He applied for European Research Council funding and obtained a Starting Grant of 1.85 million euros over five years. It its wake, he was appointed Inserm Research Officer and founded his Mucosal Microbiota in Chronic Inflammatory Diseases team in the Endocrinology, Metabolism and Diabetes Department** of Institut Cochin in Paris. "Our laboratory only opened its doors in October 2019, but there are already four of us on the team – me, two postdocs and an Assistant Engineer. Students will also be joining us soon", he says. Now there will be nothing stopping him from revealing the secrets of the microbiota and its Invaders! 👾

Microbiote, les fabuleux pouvoirs du ventre - documentary by Sylvie Gilman and Thierry de Lestrade – 59 min- 2019 (available only in French)

Notes :
* unit 1071 Inserm/Université Clermont Auvergne, Clermont-Ferrand
** unit 1016 Inserm/CNRS/Université Paris Descartes, Paris