Effect of Chidamide on the Killing Acitivity of NK Cells Targeting K562 Cells and Its Related Mechanism In Vitro / 中国实验血液学杂志

OBJECTIVE@#To investigate the effect of chidamide on the killing activity of NK (Natural killer cell, NK) cells targeting K562 cells and its related mechanism.@*METHODS@#K562 cells were pretreated with chidamide at different concentrations and cocultured with NK cells at different effect-target ratios. The killing effect of chidamide on K562 cells by NK cells, the expression of natural killer group 2 member D (NKG2D) ligands and apoptosis rate of K562 cells were detected by flow cytometry.@*RESULTS@#The killing sensitivity of NK cells to K562 cells could be enhanced by chidamide. The expression of ULBP2 on K562 cell surface could be up-regulate, however, the expression of ULBP1 and MICA/MICB showed no statistically difference as compared with control group. Chidamide showed no obvious cytotoxicity to K562 cells.@*CONCLUSION@#Chidamide can significantly improve killing efficiency of NK cells on K562 cells, which may be related to the up-regulation of ULBP2 expression.

Effect of MiR-99a-5p on the Differential Ability of Human Bone Marrow Mesenchymal Stem Cells / 中国实验血液学杂志

<p><b>OBJECTIVE</b>To investigate the effect of microRNA-99a-5p (miR-99a-5p) on differentiation ability of human bone marrow mesenchymal stem cells (BM-MSC).</p><p><b>METHODS</b>BM-MSC was cultured and then transfected with miR-99a-5p mimics or inhibitors. The transfection efficiency was detected by real-time quantitative PCR. The effects of miR-99a-5p on the adipogenic and osteogenic differentiation ability of BM-MSC were detected by differentiation experiment.</p><p><b>RESULTS</b>As compared with the negative control group, the expression of miR-99a-5p was significantly up-regulated after transfection with miR-99a-5p mimics(P<0.001), the expression of miR-99a-5p was down-regulated after transfection with miR-99a-5p inhibitor (P<0.001). In osteogenic differentiation experiments, the miR-99a-5p overexpression could promote the osteogenic differentiation, while the downregulation of miR-99a-5p expression inhibited the osteogenic differentiation. The same results were obtained by semi-quantitative detection through spectrophotometry. In the adipogenic differentiation test, transfection of miR-99a-5p mimics or inhibitors had no significant effect on the adipogenic differentiation of BM-MSC.</p><p><b>CONCLUSION</b>Overexpression of miR-99a-5p can promote the osteogenic differentiation of BM-MSC, but no significant effects are observed in the adipogenic differentiation.</p>