Gene profiling in enteroviral heart disease

The application of high-throughput genomical strategies and bioinformatical tools coupled with established molecular techniques allows researchers to gain new insights into the pathogenesis of infectious diseases. In humans, coxsackievirus B3 (CVB3) is the primary etiological agent of viral myocarditis, an inflammatory disease process involving the heart muscle. Specific therapy is currently unavailable. Viral myocarditis is a complex multiphasic infectious-inflammatory-reparative process. To address this temporal dimensionality, microarrays and non-array-based molecular techniques and histological and functional assays were used to further define enteroviral pathogenesis and its relation to heart failure. A re-analysed cDNA array-based dataset and an Affymetrix GeneChip®- based dataset from the murine heart during acute viremic, inflammatory and reparative stages were mined and compared. Global decreases in expression of metabolic and mitochondrial genes, increases in signalling, matrix and contractile protein genes, and distinctive patterns for genes in other functional groups are described. The transcript and protein profiles of heat shock protein 27, Muscle LIM protein and cathepsin L were confirmed using RT-PCR and immunohistochemistry, respectively. To focus on direct virus and host cell interactions, the transcriptional profile of CVB3-infected HeLa cells was investigated. Notably, increased expression of transcription factor c-fos downstream of extracellular signal-related kinase was found, a pathway our laboratory has previously shown to be important for virus replication and pathogenesis. The in vitro array experiment included a MEKl inhibitor treatment group. Commercial and in-house bioinformatical filtration, cluster analysis and visualization tools were used to determine potential gene targets downstream in the ERK pathway in the setting of CVB3 infection. Marked upregulation of oncogenes, serpins and matrix metalloproteinase genes, among others, were found in infected HeLa cells and in the heart. Together, our animal and cell culture array studies have contributed insight into host responses to enteroviral infections from which new testable hypotheses have been generated.Medicine, Faculty ofPathology and Laboratory Medicine, Department ofGraduat