ISOLATION AND CHARACTERIZATION OF TRANSFORMED HUMAN T-CELL LINES INFECTED BY EPSTEIN-BARR-VIRUS

Epstein-Barr virus (EBV) is a human lymphotropic virus whose main targ ets have traditionally been described as B lymphocytes and epithelial cells. Here we report the isolation and characterization of largely mo noclonal transformed human T-cell lines infected by EBV, The transform ed T cells expressed CD2, CD3, and either CD4 or CD8 surface molecules and more generally displayed the phenotype of naive T cells with a co mplete and clonal rearrangement of the T-cell receptor, None of the ce ll lines expressed B cells, natural killer, or myeloid antigens or had immunoglobulins genes rearrangement. They grew in the absence of grow th factor; however, they all secreted interleukin-2 after mitogenic ac tivation, Polymerase chain reaction (PCR) analysis showed the presence of EBV DMA in all these cell lines. Moreover, Southern blot analysis of one of these cell lines shows the presence of circular episomic EBV DNA, and by Northern blot or reverse transcriptase-PCR analysis, only the expression of Epstein-Barr nuclear antigen-1 (EBNA-1) and latent membrane protein-1 (LMP-1) genes was detected. Finally, the complete t ransformed phenotype of this T-cell line was shown by its injection in to nude or recombination activating gene 2 (RAG2)-deficient mice that led to the formation of solid tumors. (C) 1997 by The American Society of Hematology.