Figure 18.  Lack of synergy between IL15 and IL2 for the growth of immature NK cells

The finding that immature and mature NK cells express IL2Ra chains that appear to be present in

high affinity complexes suggested that low concentrations of IL2 may be able to enhance the growth

of NK cells in the presence of limiting doses of IL15.  To examine this possibility, E14 progenitors

were grown for 2 days in IL4 + PMA then transferred to medium containing various dose of IL15

in combination with various amounts of IL2.  Growth was measured 3 days later.

Conclusions

1.  IL2 at low concentrations [0.2nM and 2nM] did not enhance the growth of immature NK cells at any

dose of IL15 tested.

2.  A similar lack of synergy between IL15 and IL2 for the growth of mature adult NK cells was found

[data not shown].