Publishing a scientific study in a high-impact journal is not easy, yet Nathalie Labrecque from the Centre de recherche de l'Hôpital Maisonneuve-Rosemont (CR-HMR) did it twice, with two articles in prestigious publications, the first of which appeared in the Proceedings of the National Academy of Sciences of the United States of America (PNAS).
Nathalie Labrecque is the chief of the Molecular Immunology Unit and the associate chief of the Immunology-Oncology Axis at the CR-HMR. She is also a full professor in the Faculty of Medicine and the Department of Microbiology, Infectious Diseases and Immunology at Université de Montréal.
The role of NR4A3
In collaboration with the teams of Sylvie Lesage at the CR-HMR and the late Dr. Cheolho Cheong at the Montreal Clinical Research Institute, Nathalie Labrecque’s work has elucidated the role of the transcription factor NR4A3 in the differentiation of a subtype of dendritic cells called monocyte-derived dendritic cells. Without NR4A3, these dendritic cells are no longer produced, which demonstrates that this transcription factor plays a key role in initiating the T-lymphocyte response to certain bacterial infections.
These results suggest that targeting NR4A3 could offer new tools to fight bacterial infections and new vaccine strategies using dendritic cells.
Dendritic cells play a sentinel role in the immune system. They recognize infectious agents and inform T lymphocytes of the danger. This triggers the response of T lymphocytes, which play a key role in controlling infection. This T-lymphocyte response also creates immunological memory, which protects us from reinfection from the same infectious agent.
Learn more
- Read the paper : The orphan nuclear receptor NR4A3 controls the differentiation of monocyte-derived dendritic cells following microbial stimulation, Salix Boulet, Jean-François Daudelin, Livia Odagiu, Adam-Nicolas Pelletier, Tae Jin Yun, Sylvie Lesage, Cheolho Cheong, Nathalie Labrecque, PNAS, juillet 2019, 116 (30) 15150-15159; DOI: 10.1073/pnas.1821296116
Influence of the biological clock on the immune response
The second study was conducted by a team led by Nicolas Cermakian of the Douglas Mental Health University Institute Research Centre and Nathalie Labrecque. Their work shows that the biological clock influences immune response efficacy. For example, the function of CD8 T cells, which are essential for controlling infections and cancers, varies greatly depending on the time of day or night.
“Our study shows that T cells are more prone to be activated at certain times of the day. Identifying the mechanisms through which the biological clock modulates the T cell response will help us better understand the processes that regulate optimal T cell responses. This knowledge will contribute to improving vaccination strategies and cancer immune therapies,” said Nathalie Labrecque.
Learn more
- Read the paper: LaPresse+
- Read the paper : Medical Xpress
- Read the paper : The circadian clock of CD8 T cells modulates their early response to vaccination and the rhythmicity of related signaling pathways, Chloé C. Nobis, Geneviève Dubeau Laramée, Laura Kervezee, Dave Maurice De Sousa, Nathalie Labrecque, Nicolas Cermakian, PNAS, Octobre 2019, 116 (40) 20077-20086; DOI: 10.1073/pnas.1905080116