Generation of a doxycycline-inducible KSHV producer cell line of endothelial origin: Maintenance of tight latency with efficient reactivation upon induction

Kaposi's sarcoma-associated herpesvirus (KSHV) is the etiological agent of Kaposi's sarcoma (KS) and at least two B cell lymphoproliferative diseases: primary effusion lymphoma (PEL) and multicentric Castleman's disease (MCD). B cells derived from PEL are latently infected, and can be induced to lytic replication by treatment with chemical agents like TPA or butyrate, which have pleiotropic effects on host cell signaling and chromatin structure. Most of these lines also display moderate levels of spontaneous lytic induction, which complicates analysis of latency. Here we describe the creation of latently infected cell lines derived from SLK endothelial cells that (i) display tight control of KSHV latency, with little spontaneous reactivation and (ii) are efficiently inducible by doxycycline, avoiding the need for pleiotropic inducing agents. These cells produce substantial quantities of infectious KSHV, and should be useful for studies of the latent-lytic switch and the impact of lytic replication on host cell biology.