Genetic Determinants of Coxsackievirus B3 Pathogenesis

Abstract

Enteric viruses are among the most common infectious human viruses worldwide, causing an estimated 10-15 million infections per year in the United States. Among enteric viruses, Coxsackievirus is commonly isolated and can lead to the development of meningitis, encephalitis, pancreatitis, and hepatitis. Furthermore, Coxsackievirus B3 is the primary cause of viral myocarditis and can lead to pleurodynia, with nearly 40,000 symptomatic cases reported in the United States each year. The enteroviral ssRNA genome contains a 5’ untranslated region (5’UTR) which consists of two structural components, the cloverleaf and the internal ribosome entry site (IRES), both shown to be integral to viral success. Additionally, the viral genome encodes four structural VP proteins as well as 11 non-structural proteins. Polymorphisms found within the CVB3 population have been linked to viral virulence. Here, we compare two CVB3 Nancy variants to elucidate the downstream effects observed in response to mutations found in the CVB3 genome. Implementing our novel oral inoculation model, we aimed to determine the impact mutations found in the 5’UTR and VP regions exert on viral pathogenesis. We also aimed to delineate the in vitro effects of the observed mutations. We investigated the role mutations found in the structural regions played in virus host cell attachment, in vitro cell viability, and replication. Our work has further confirmed the relevance and impact of mutations found in the VP region of the CVB3 genome.