Séminaire CIRI (25.09.2025): Akatsuki SAITO

Akatsuki SAITO, University of Miyazaki Miyazaki, Japan), “ Non-human primate models for viral infections ”

Abstract: Due to their physiological and genetic similarities to humans, non-human primates (NHPs), such as rhesus and cynomolgus monkeys, serve as indispensable models for evaluating vaccines and therapeutics, as well as for studying the pathogenesis of human viral infections. However, not all viruses that cause human diseases replicate efficiently or manifest comparable pathologies in macaques. Therefore, understanding virus–host interactions, often referred to as the “arms race,” is critical for the rational development of primate models.
The host range of HIV-1, the causative agent of acquired immunodeficiency syndrome (AIDS), is extremely narrow, with productive replication occurring only in humans and chimpanzees. For many years, the reason why HIV-1 fails to replicate in macaque cells remained unclear. About two decades ago, several host cellular factors that restrict HIV-1 replication in macaque cells were identified. Among these, tripartite motif-containing protein 5α (TRIM5α) was found to be a major anti-HIV-1 restriction factor in macaque cells. TRIM5α potently inhibits HIV-1 replication after viral entry by blocking uncoating and subsequent reverse transcription.
Subsequent studies clarified the functional domains of viral proteins that interact with these HIV-1 restriction factors and elucidated their molecular mechanisms. These insights facilitated the development of HIV-1 variants capable of replicating in macaque cells, known as macaque-tropic HIV-1. During these studies, we found that specific genetic backgrounds have a strong influence on susceptibility to macaque-tropic HIV-1. This finding has enabled the prediction of viral susceptibility, thereby contributing to the establishment of more accurate and reliable animal models.
Furthermore, our laboratory is actively utilizing animal models for other viruses, including SARS-CoV-2, hepatitis B virus, and Zika virus. In addition to human viral infections, we are also investigating viral diseases in animals.
In this seminar, I will introduce our ongoing collaborative studies on domestic cat hepatitis B virus in partnership with Dr. David Durantel (INSERM), as well as our joint research on retroviruses in sheep and goats with Dr. Jocelyn Turpin and Dr. Caroline Leroux. I will also share some of our latest findings from these projects during today’s seminar.

Hôte : Caroline Leroux & David Durantel