CIIL - NEWSLETTER , november 2026 - N° 20

After obtaining my Engineering degree in Biochemistry from INSA Lyon in 1997, I pursued a PhD in Fundamental Microbiology at Université Paris VII, within the Microbiology and Genetics Unit at INSA Lyon (CNRS UMR 5122). My early research focused on the transcriptional regulation of virulence factors in the phytopathogenic bacterium Erwinia chrysanthemi.

Following my PhD, I joined the laboratory headed by Dr. C. Locht at Institut Pasteur de Lille, with the aim of pursuing research with a direct impact on human health. I was subsequently recruited in 2003 as a Research Scientist at Institut Pasteur de Lille, within the same team. My work then focused on Mycobacterium tuberculosis, and more specifically on the preclinical evaluation of a novel subunit vaccine candidate against tuberculosis. We investigated the protective efficacy of the mycobacterial antigen HBHA (Heparin-Binding Haemagglutinin), a multifunctional protein involved in adhesion to non-phagocytic cells and extrapulmonary dissemination. We showed that subcutaneous administration of HBHA, in the presence of a Th1-promoting adjuvant, induced protection similar to the one conferred by Bacille Calmette-Guérin (BCG). Given the broad coverage of BCG vaccination worldwide, we also demonstrated that HBHA constitutes a promising booster vaccine candidate, with the potential to enhance and/or prolong the protective immune response induced by previous BCG vaccination.

Building on this work on vaccination strategies, I studied the influence of the co-administration of two live vaccines on their homologous and heterologous protective effects. More precisely, I was interested in BCG, the only vaccine currently available against tuberculosis, and BPZE1, a nasal pertussis vaccine candidate developed within our laboratory. Our data showed that, in a juvenile mouse model, co-administration of BCG and BPZE1 did not result in detrimental immunological interference between the two live vaccines. These findings support the clinical development of BPZE1, which is currently undergoing Phase III clinical trials, and its potential future administration to infants.

Since 2020, I have developed a strong interest in alveolar macrophages, given their strategic position at the interface between inhaled pathogens and the immune system. Understanding their role in the control of respiratory infections, bacterial persistence and trained immunity is now the main focus of my research. In collaboration with Dr. Nathalie Mielcarek, we have investigated the interactions between B. pertussis, the causative agent of whooping cough, and alveolar macrophages. This work led us to study the mechanisms regulating the macrophage inflammatory response and those involved in intracellular bacterial degradation and clearance, with a particular focus on the role of autophagy, which has been little studied in this context. This project is still ongoing and now aims to determine how B. pertussis virulence factors modulate its intracellular fate within alveolar macrophages.

In parallel, in collaboration with Dr. Fernando Real (head of the CVI team, CIIL) and with the support of INSERM Transfert, we are developing innovative models of human alveolar macrophages derived from induced pluripotent stem cells (hiPSCs). These models will enable us to investigate the mechanisms underlying BCG-induced trained immunity.

Altogether, this work is driven by a strong collective effort, supported in particular by close collaboration with Dr. Nathalie Mielcarek and by the strong involvement of Guillaume Camus, who is currently pursuing his PhD at Université de Lille under our joint supervision.