Arenaviruses include several causative agents of hemorrhagic fever disease in humans. In addition, the prototypic arenavirus lymphocytic choriomeningitis virus (LCMV) is a superb model for the study of virus-host interactions, including the basis of viral persistence and associated diseases. The molecular mechanisms concerning the regulation and specific role of viral proteins in modulating arenavirus-host cell interactions associated either with an acute or persistent infection and associated disease remain little understood. In this project I have performed the genomic and biological characterization of LCMV strains Docile (persistent) and Aggressive (not persistent) recovered from cloned cDNA via reverse genetics. The results confirmed that the cloned viruses accurately recreated the in vivo phenotypes associated with the corresponding natural Docile and Aggressive viral isolates. In addition, we provide evidence that the ability of the Docile strain to persist is determined by the nature of both S and L RNA segments. Thus, our findings provide the foundation for studies aimed at gaining a detailed understanding of viral determinants of LCMV persistence in its natural host that may aid in the development of vaccines to prevent or treat the diseases caused by arenaviruses in humans.

Index Words: Viral infection, LCMV, Arenaviruses, RNA virus, T-cell response, Reverse genetics technique, Viral persistence.