CONSTRUCTION OF AN ADENOVIRUS VECTOR EXPRESSING THE LATENT LOCUS OF KAPOSI'S SARCOMA-ASSOCIATED HERPESVIRUS
Breanna Wentz, Michael Lagunoff.
University of Washington, Seattle, WA.
Kaposi’s sarcoma-associated herpesvirus (KSHV) is a human pathogenic γ-herpes virus and is the infectious cause of Kaposi’s sarcoma (KS). The KS tumor is highly vascularized and is characterized by latently infected spindle cells of endothelial origin. While in the KS tumor 1 to 5% of the cells are lytic and producing new virons, greater than 90% are latently infected and not producing virus. Our lab and others have previously shown that KSHV induces angiogenic phenotypes, altered cell metabolism, and oncogenic signal transduction. The current goal is to investigate if the major latent locus genes expressed by KSHV are sufficient to alter endothelial cells to induce the described phenotypes or if the small percentage of lytic genes play a paracrine role. We have cloned the entire 12 kbp KSHV latent locus into a gutted adenovirus expression vector that eliminates the contamination from expression of adenovirus genes. The latent locus includes the 4 genes expressed during latency and the 12 virally encoded microRNA loci. The adenovirus vector expressing the latent locus will be used to infect endothelial cells, and we will examine the cells expressing the KSHV latent locus for changes in factors involved in angiogenesis, metabolic pathways, and oncogenic cell signaling. If the latent genes recapitulate the pathways of a KS infection, this will indicate that latent gene expression alone, without the low percentage of lytic genes in the culture, is sufficient to induce many cellular pathways activated by KSHV that are relevant for the pathogenesis of KS tumors.