title: The RBP-Jκ binding sites within the RTA promoter regulate KSHV latent infection and cell proliferation.
abstract: Kaposi's sarcoma-associated herpesvirus (KSHV) is tightly linked to at least two lymphoproliferative disorders, primary effusion lymphoma (PEL) and multicentric Castleman's disease (MCD). However, the development of KSHV-mediated lymphoproliferative disease is not fully understood. Here, we generated two recombinant KSHV viruses deleted for the first RBP-Jκ binding site (RTA(1st)) and all three RBP-Jκ binding sites (RTA(all)) within the RTA promoter. Our results showed that RTA(1st) and RTA(all) recombinant viruses possess increased viral latency and a decreased capability for lytic replication in HEK 293 cells, enhancing colony formation and proliferation of infected cells. Furthermore, recombinant RTA(1st) and RTA(all) viruses showed greater infectivity in human peripheral blood mononuclear cells (PBMCs) relative to wt KSHV. Interestingly, KSHV BAC36 wt, RTA(1st) and RTA(all) recombinant viruses infected both T and B cells and all three viruses efficiently infected T and B cells in a time-dependent manner early after infection. Also, the capability of both RTA(1st) and RTA(all) recombinant viruses to infect CD19+ B cells was significantly enhanced. Surprisingly, RTA(1st) and RTA(all) recombinant viruses showed greater infectivity for CD3+ T cells up to 7 days. Furthermore, studies in Telomerase-immortalized human umbilical vein endothelial (TIVE) cells infected with KSHV corroborated our data that RTA(1st) and RTA(all) recombinant viruses have enhanced ability to persist in latently infected cells with increased proliferation. These recombinant viruses now provide a model to explore early stages of primary infection in human PBMCs and development of KSHV-associated lymphoproliferative diseases.
authors.affiliation: Department of Microbiology and Tumor Virology Program of the Abramson Cancer Center, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania, United States of America.
authors.forename: Jie
authors.initials: J
authors.lastname: Lu
authors.forename: Subhash C
authors.initials: SC
authors.lastname: Verma
authors.forename: Qiliang
authors.initials: Q
authors.lastname: Cai
authors.forename: Abhik
authors.initials: A
authors.lastname: Saha
authors.forename: Richard Kuo
authors.initials: RK
authors.lastname: Dzeng
authors.forename: Erle S
authors.initials: ES
authors.lastname: Robertson
mesh_terms: D001665:Binding Sites / Q000235:genetics; D049109:Cell Proliferation; D002478:Cells, Cultured; D015967:Gene Expression Regulation, Viral; D057809:HEK293 Cells; D006566:Herpesviridae Infections / Q000150:complications / Q000235:genetics / Q000378:metabolism / Q000821:virology; D019288:Herpesvirus 8, Human / Q000235:genetics* / Q000254:growth & development / Q000502:physiology*; D006801:Humans; D017874:Immediate-Early Proteins / Q000235:genetics* / Q000378:metabolism; D051819:Immunoglobulin J Recombination Signal Sequence-Binding Protein / Q000737:chemistry / Q000378:metabolism*; D008232:Lymphoproliferative Disorders / Q000209:etiology / Q000235:genetics / Q000821:virology; D011401:Promoter Regions, Genetic / Q000235:genetics; D011485:Protein Binding; D015534:Trans-Activators / Q000235:genetics* / Q000378:metabolism; D017735:Virus Latency / Q000235:genetics*
chemical_list: D017874:Immediate-Early Proteins; D051819:Immunoglobulin J Recombination Signal Sequence-Binding Protein; C417604:Rta protein, Human herpesvirus 8; D015534:Trans-Activators