Infection of primary dermal microvascular endothelial cells by Kaposi's sarcoma-associated herpesvirus.

Abstract

To develop an in vitro model for infection of primary human cells with Kaposi's sarcoma (KS) herpesvirus (KSHV). The recent identification of a herpesvirus associated with KS, its successful isolation in vitro, and its complete DNA sequencing facilitates experiments on the pathogenesis of AIDS-related KS. Completed studies demonstrate that the endothelial cells lining the vascular slits in KS lesions are productively infected with KSHV and may be the principal site of virus replication. We have designed a model system to study the infection of primary human cells with KSHV. A coculture technique was used with KS cells (KS-1) and primary dermal microvascular endothelial cells. We detected increasing viral DNA concentrations as well as viral mRNA suggesting that a productive virus infection occurs in the target cells. Infection of these cells is dose- and time-dependent and is inhibited by lobucavir, foscarnet and 9-(2-phosphomethoxyethyl) adenine. With a modification of the model, KSHV can be serially passaged in primary cells in excess of 16 passages. This novel model assay system makes new studies on the role of KSHV and KSHV-induced cellular products on the pathogenesis of KS possible. It also provides a high volume screening method to detect agents that inhibit KSHV infection of primary endothelial cells.