FcRL6 can be down-regulated on NK cells by activating cytokines. Activation of NK cells with IL-2 or IL-15 leads to up-regulation of the surface marker CD56 and down-regulation of FcRL6. The differentiation of resting NK cells from CD56^dim “cytotoxic” to CD56^bright “regulatory” NK-cell phenotypes with IL-12 stimulation also leads to down-regulation of FcRL6.