Analysis of CXCR7 expression and function in MZ B cells. (A) Splenocytes were analyzed for expression of CXCR7 by indicated cell population by flow cytometry. Non-B indicates CD19⁻ cells; FO, follicular B cells; MZ, MZ B cells; Tr, transitional B cells (refer to panel B for gating schemes). (B) The percentages of splenic B-cell subsets in mice treated with CCX754 or vehicle for 2 days. The numbers indicate percentages of cells falling in each gate. (C) Changes in the indicated cell subsets after CCX754 treatment for 2 days. Data represent 3 independent experiments, totaling 9 mice (means ± SEM). (D) Splenic frozen sections of indicated mice were stained with fluorescent Abs (indicated). The triangles in the right panel indicate disorganized MZ B-cell band. Original magnification ×10 for all images. (E) Percentages of MZ and FO B cells in mice treated with CCX771 or vehicle for 3 days. Each symbol represents a mouse. Data are representative of 3 separate experiments with similar results. Horizontal bars represent the median values.