Figure 1. Expansion and immunophenotypes of NK cells cocultured with K562-mb15-41BBL cells.
(A) Peripheral blood mononuclear cells from five healthy donors and from four pediatric patients in first hematological remission of B-cell precursor ALL were cocultured with irradiated K562mb15-4-1BBL at a 0.75:1 ratio in the presence of rhIL-2 (40 IU/ml), and absolute numbers of NK cells were calculated every 5 days after staining of viable cells with CD3- and CD56-specific antibodies. (B) Cell surface expression of CD3 and CD56 prior to and on days 5 and 10 after stimulation by flow cytometry, and expression of CD56, CD16, CD244 (2B4) and CD48 on day 10 of coculture with K562-mb15-41BBL cells. Shown are representative histograms for one of five cell cultures obtained from four donors.