ESTABLISHMENT AND CHARACTERIZATION OF A PRIMARY EFFUSION (BODY CAVITY-BASED) LYMPHOMA CELL-LINE (BC-3) HARBORING KAPOSIS SARCOMA-ASSOCIATEDHERPESVIRUS (KSHV HHV-8) IN THE ABSENCE OF EPSTEIN-BARR-VIRUS/

The recently identified Kaposi's sarcoma-associated herpesvirus (KSHV) , also known as human herpesvirus 8 (HHV-8), has been found to be cons istently associated with an unusual subset of acquired immunodeficienc y syndrome-related lymphomas, the so-called body cavity-based lymphoma s (BCBL) or primary effusion lymphomas (PEL). These lymphomas are char acterized by a unique spectrum of morphologic and molecular characteri stics, and grow as lymphomatous effusions without an identifiable cont iguous tumor mass. Until now, efforts to delineate the role of KSHV in the pathogenesis of PELs have been hampered by the lack of appropriat e model systems and the concomitant presence of Epstein-Barr virus (EB V) in nearly ail cases examined, and in all previously established cel l lines. We now report the establishment and characterization of a nov el PEL cell line, BC-3, which is KSHV+ by polymerase chain reaction (P CR) but EBV(-) as assessed by a variety of methods including PCR for E BER, EBNA-2, and EBNA-3C, This cell line was established from a lympho matous effusion obtained from an HIV- patient, and has immunophenotypi c and molecular features consistent with the diagnosis of PEL, includi ng an indeterminate immunophenotype with a B-cell immunogenotype and l ack of c-myc proto-oncogene rearrangements, Pulsed-field gel electroph oresis shows an intact KSHV genome of about 170 kb both in the cell li ne and in the viral isolate, whereas herpesvirus-like capsids are visi ble by electron microscopy. Consequently, the BC-3 cell line represent s an invaluable tool as a source of KSHV, for both the evaluation of t he pathogenic potential of this virus and the mechanistic characteriza tion of its role in the development of Kaposi's sarcoma and malignant lymphoma. (C) 1996 by The American Society of Hematology.