Submitted April 28, 2006
Accepted July 18, 2006
Coordinated acquisition of inhibitory and activating
receptors and functional properties by developing human
natural killer cells
Bartosz Grzywacz, Nandini Kataria, Magdalena Sikora, Robert A. Oostendorp, Elaine A. Dzierzak, Bruce R. Blazar, Jeffrey S. Miller, and Michael R Verneris*
University of Minnesota
Erasmus University
* Corresponding author; email: verneris{at}umn.edu.
The stages of human NK cell differentiation are not well
established. Culturing CD34+ progenitors with IL-7, IL-
15, SCF, FLT-3L and murine fetal liver cell line
(EL08.1D2), we identified 2 non-overlapping subsets of
differentiating CD56+ cells based on CD117 and CD94
(CD117highCD94- and CD117low/-CD94+ cells). Both
populations expressed CD161 and NKp44, but differed with
respect to NKp30, NKp46, NKG2A, NKG2C, NKG2D, CD8, CD16
and KIR. Only the CD117low/-CD94+ population displayed
cytotoxicity and interferon-
production. Both
populations arose from a single CD34+CD38-Lin- cell and
their percentages changed over time in a reciprocal
fashion, with CD117highCD94- cells predominating early
and decreasing due to an increase of the CD117low/-CD94+
population. These two subsets represent distinct stages
of NK cell differentiation, since purified CD117highCD94-
give rise to CD117low/-CD94+ cells. The stromal cell
line (EL08.1D2) facilitated the transition from
CD117highCD94- to CD117low/-CD94++ via an intermediate
phenotype (CD117lowCD94low/-). EL08.1D2 also maintained
the mature phenotype, preventing the reversion of
CD117low/-CD94+ cells to the intermediate
(CD117lowCD94low/-) phenotype. An analogous population
of CD56+ CD117highCD94- cells was found in cord blood.
The identified stages of NK cell differentiation provide
evidence for coordinated acquisition of HLA specific
inhibitory receptors (i.e., CD94/NKG2A) and function in
developing human NK cells.
