Chemokine receptor expression profile and chemotaxis of iNK and mNK cells from different anatomic compartments. (A) Freshly isolated cells from BM, spleen, and blood of individual C57BL/6 mice were stained with specific antibodies against CXCR4, CXCR3, CCR5, and CCR1 in combination with anti-NK1.1–, anti-CD3ϵ–, and DX5-specific antibodies. Expression of chemokine receptors was analyzed on DX5⁻ and DX5⁺ NK cells (NK1.1⁺CD3⁻) of the electronically gated lymphocytes. Numbers in the dot plots indicate the percentage of positive cells within the iNK (DX5⁻, bottom left and right) and mNK (DX5⁺, top left and right) cell populations. A representative experiment of 6 performed is shown. (B,C) In vitro chemotaxis assay of cells isolated from different organs was performed as described in “Methods” and in Figure 1B legend. mNK and iNK cell migration was quantified by enumerating the positive events contained in the NK1.1⁺/CD3⁻/DX5⁺ gate (mNK, B) and in the NK1.1⁺/CD3⁻/DX5⁻ gate (iNK, C) after 150-second acquisition for BM and blood cells and 75-second acquisition for spleen cells. Results presented are the means plus or minus SD of 6 independent experiments. Student t test was performed by comparing migration of mNK cells (B) or iNK cells (C) from different anatomic compartments from each other; *P < .05. Differences that are not statistically significant are omitted for sake of simplicity.