Cellular localization of IκBζ in human NK cells. The cellular localization of IκBζ expression was evaluated in CD56⁺ human NK cells stimulated with recombinant IL-12 and IL-18 (10 ng/mL each) over time. The cellular lysates were fractionated into the nucleus and the cytosol separately. The cell lysates were immunoblotted for IκBζ, lamin B1 (nuclear marker), and LDH (cytosolic marker–lactate dehydrogenase). The immunoblot is representative of 3 independent experiments. *Nonspecific band. **Nonspecific band.