GENERATION OF HUMAN NATURAL-KILLER-CELLS FROM PERIPHERAL-BLOOD CD34(-COLONY-STIMULATING FACTOR() CELLS MOBILIZED BY GRANULOCYTE)

We studied the generation of human natural killer (NK) cells from CD34 (+) cells that were isolated from peripheral blood stem cells (PBSC) m obilized by granulocyte colony-stimulating factor (G-CSF). The isolate d CD34(+) cells were cultured in the presence of a combination of inte rleukin-1 (IL-1 alpha), IL-2, and stem cell factor for 5 weeks without marrow stroma. We found that the CD34(+) cells isolated from G-CSF-mo bilized PBSC (G-CSF/PBSC) could differentiate into a population of NK cells which were CD56(+(bright))/CD3(-) and showed morphologic charact eristics of large granular lymphocytes. Immunophenotypic analysis of t he NK cells thus generated showed that a small proportion of them expr essed CD2, CD8 and CD16 surface markers and approximately half of them coexpressed CD7. This NK population exhibited cytotoxic activity agai nst a NK-sensitive cell line, K562. These observations suggest that CD 34(+) cells from G-CSF/PBSC contain precursors of NK cells that can di fferentiate into functional NK cells.