A Mouse Model of Chronic West Nile Virus Infection

Here, we characterize the RIX line CC(032x013)F1, which serves as a mouse model of chronic WNV infection. While studies using C57BL/6 mice have shown that WNV RNA can persist in the CNS up to 3 months post infection in a limited fraction of mice (Appler et al., 2010), to date there is a lack of a robust mouse model of chronic West Nile virus infection that can be used to elucidate the immune responses associated with this viral persistence and chronicity of symptoms described in human patients. Here, we characterize this line in comparison with lines showing either no disease symptoms or significant disease, and suggest a mechanism by which WNV infection can become chronic through alterations in immune responses. Microarrays were performed on spleen samples from mice collected at days 7,12,21,28 post-infection with west nile virus or from time-matched mock-infected animals.