Rapid protection induced by a single-shot Lassa vaccine in male cynomolgus monkeys

Mathieu Mateo (1, 2) , Stéphanie Reynard (1, 2) , Natalia Pietrosemoli (3) , Emeline Perthame (3) , Alexandra Journeaux (1, 2) , Kodie Noy (1, 2) , Clara Germain (1, 2) , Xavier Carnec (1, 2) , Caroline Picard (1, 2) , Virginie Borges-Cardoso (1, 2) , Jimmy Hortion (1, 2) , Hélène Lopez-Maestre (3) , Pierrick Regnard (4) , Lyne Fellmann (5) , Audrey Vallve (6) , Stéphane Barron (6) , Ophélie Jourjon (6) , Orianne Lacroix (6) , Aurélie Duthey (6) , Manon Dirheimer (7) , Maïlys Daniau (8) , Catherine Legras-Lachuer (8) , Caroline Carbonnelle (6) , Hervé Raoul (6) , Frédéric Tangy (9) , Sylvain Baize (1, 2)

1 UBIVE - Biologie des Infections Virales Émergentes - Biology of Emerging Viral Infections
2 CIRI - Centre International de Recherche en Infectiologie
3 Hub Bioinformatique et Biostatistique - Bioinformatics and Biostatistics HUB
4 UNISTRA - Université de Strasbourg
5 SILABE - Simian Laboratory Europe
6 Unité de service 3 - Laboratoire P4 Jean Mérieux-Inserm [Lyon]
7 Délégation régionale Auvergne Rhône-Alpes [Bron, France]
8 ViroScan3D SAS [Trévoux, France]
9 Laboratoire d’innovation : vaccins – Innovation lab : vaccines

Lassa fever hits West African countries annually in the absence of licensed vaccine to limit the burden of this viral hemorrhagic fever. We previously developed MeV-NP, a single-shot vaccine protecting cynomolgus monkeys against divergent strains one month or more than a year before Lassa virus infection. Given the limited dissemination area during outbreaks and the risk of nosocomial transmission, a vaccine inducing rapid protection could be useful to protect exposed people during outbreaks in the absence of preventive vaccination. Here, we test whether the time to protection can be reduced after immunization by challenging measles virus pre-immune male cynomolgus monkeys sixteen or eight days after a single shot of MeV-NP. None of the immunized monkeys develop disease and they rapidly control viral replication. Animals immunized eight days before the challenge are the best controllers, producing a strong CD8 T-cell response against the viral glycoprotein. A group of animals was also vaccinated one hour after the challenge, but was not protected and succumbed to the disease as the control animals. This study demonstrates that MeV-NP can induce a rapid protective immune response against Lassa fever in the presence of MeV pre-existing immunity but can likely not be used as therapeutic vaccine.

Domaines: Sciences du Vivant [q-bio]

Mathieu Mateo, Stéphanie Reynard, Natalia Pietrosemoli, Emeline Perthame, Alexandra Journeaux, et al.. Rapid protection induced by a single-shot Lassa vaccine in male cynomolgus monkeys. Nature Communications, 2023, 14 (1), pp.1352. ⟨10.1038/s41467-023-37050-6⟩. ⟨pasteur-04122340⟩