CHARACTERIZATION OF A NOVEL HUMAN NATURAL-KILLER-CELL LINE (NK-YS) ESTABLISHED FROM NATURAL-KILLER-CELL LYMPHOMA LEUKEMIA ASSOCIATED WITH EPSTEIN-BARR-VIRUS INFECTION/

A novel cell line was established from a patient with a leukemic-state nasal angiocentric natural killer (NK) cell lymphoma with systemic sk in infiltration. The morphology of the leukemic cells was large-granul ar-lymphocyte (LGL), and their immunophenotype was CD2(+), CD3(-), CD5 (+), CD7(+), CD16(-), CD56(+), and CD57(-). Phe presence of Epstein-Ba rr viral (EBV) genome was shown in specimens from the patient's nose, shin, and peripheral blood by in situ hybridization using an EBV-encod ed small RNA-1 probe or by Southern blotting using a terminal-repeat p robe of the EBV genome. Leukemic cells were cocultured with a mouse st romal cell line (SPY3-2) in the presence of 100 U/mL recombinant human interleukin-9 and a novel stromal cell-independent cell line, NK-YS, was established. The NK-YS cells showed LGL morphology and expressed s urface CD2, CD5, CD7, CD25, CD56, and CD95. The NK-YS cells retained c ytotoxicity against K562 and Jurkat cells. A Southern blotting using a terminal-repeat probe of EBV showed that NK-YS and fresh leukemic cel ls had a clonal EBV genome, whereas the T-cell receptor beta and gamma chain genes of NK-YS were not rearranged. In an immunocytochemical an alysis, the NK-YS cells showed a type-II latent infection of EBV. The NK-YS cells preserved the original characteristics of NK cell lymphoma /leukemia and will be a useful tool for the study of biological charac teristics of EBV-associated nasal angiocentric NK cell lymphoma/leukem ia. (C) 1998 by The American Society of Hematology.