Fig. 2

CXCR7 inhibition reduced homing of U937 and normal CD34⁺ cells to hematopoietic organs. U937 and CD34⁺ cells in which CXCR7 and/or CXCR4 were inhibited were labeled with CFSE and then injected into the tail vein of sub-lethally irradiated (3.75 Gy) female NOD/SCID mice. Bone marrow and spleen were harvested and analyzed by flow cytometry for CFSE⁺ cells 16 h after transplantation. a The inhibition of CXCR7 by shRNA or by blocking CXCR4 using monoclonal antibody CXCR4-clone 12G5 reduced U937 cell homing to bone marrow. CXCR7 inhibition plus CXCR4 blocking promoted the same effect. b Blocking of CXCR7 by CXCR7 mAb-clone 11G8 or CXCR4 by CXCR4 mAb-clone 12G5 or both receptors together reduced the homing of CD34⁺ cells to bone marrow. Reduction of homing to spleen was also observed for U937 (c) and CD34⁺ (d) cells with inhibition of CXCR7 or CXCR4 or both receptors together. Data represent four independent experiments using two different donors. **p < 0.01; ***p < 0.001; 1-way ANOVA and Tukey’s multiple comparison test. Error bars represent standard deviation