Fig. 1

Inhibition of HDAC upregulates surface CXCR4 expression and promotes homing of human hematopoietic stem and progenitor cells. a Mean fluorescence intensity (MFI) of surface CXCR4 of human CB CD34⁺ cells after treating cells for 16 h with compounds (1 μM) from the SCREEN-WELL Epigenetics Library. One compound, BML-266, was excluded from the results because of unspecific autofluorescence. b Histogram of surface CXCR4 expression of human CB CD34⁺ cells treated with vehicle or HDAC inhibitor M344. Representative histogram from five independent experiments is shown. c Quantification of mean fluorescence intensity (MFI) of surface CXCR4 of human CB CD34⁺ cells treated with vehicle or HDAC inhibitor M344. None indicates the group without any treatment. Data pooled from five independent experiments are shown (n = 5, one-way ANOVA, ***p < 0.001). d Confocal imaging analysis of surface CXCR4 expression of human CB CD34⁺ cells treated with vehicle or M344. FITC (green) indicates CXCR4 expression; DAPI (blue) labels the cell nucleus. Representative images from two independent experiments are shown (the inset shows the amplified part of the image). Scale bar: 20 μm. e Quantification of mean fluorescence intensity (MFI) of surface CXCR4 of human CB HSCs (CD34⁺CD38⁻CD45RA⁻CD90⁺CD49f⁺) treated with vehicle or M344. None indicates the group without any treatment. Data pooled from five independent experiments are shown (n = 5, one-way ANOVA, ***p < 0.001). f Chemotaxis of human CB CD34⁺ cells toward human recombinant SDF-1, as quantified by flow cytometry. Data pooled from three independent experiments are shown (each dot represents an independent chemotaxis, n = 3 CB samples, one-way ANOVA, **p < 0.01, ***p < 0.001). g Migration of human phenotypic HSCs in CB CD34⁺ cells toward human recombinant SDF-1 (50 ng/mL), as quantified by flow cytometry. The migration percentage of HSCs was calculated by analyzing the HSC (CD34⁺CD38⁻CD45RA⁻CD90⁺CD49f⁺) frequency using flow cytometry. Data pooled from three independent experiments are shown (each dot represents an independent chemotaxis, n = 3 CB samples, t-test, **p < 0.01). h The percentage of human CD45⁺ cells in the BM and spleen of NSG mice 24 h after transplantation with 500,000 CB CD34⁺ cells that had been treated with vehicle or M344. Data pooled from seven independent experiments are shown (n = 7 mice per group, t-test, **p < 0.01, ***p < 0.001). For all panels, data are shown as dot plots (mean ± SEM)