CXCL12过表达促进骨髓基质干细胞整合素 /介导的黏附和增殖

目的 研究利用骨髓基质干细胞移植治疗急性心肌梗死时趋化因子CXCL12过表达对由整合素介导αV/β3的干细胞黏附和增殖过程的影响。方法 采用重组DNA技术使得骨髓基质干细胞过表达趋化因子CXCL12，采用Western-blot法检测CXCL12过表达后骨髓基质干细胞整合素αV/β3表达量的变化。在体外通过黏附实验观察趋化因子CXCL12过表达对整合素介导的细胞与细胞外基质黏附过程的影响，并在心肌梗死大鼠模型中通过检测报告基因观测CXCL12对移植后整合素介导骨髓基质干细胞增殖的作用。结果 基因重组后骨髓基质干细胞过表达了具有生物活性的趋化因子CXCL12，趋化因子CXCL12过表达使骨髓基质干细胞整合素αV/β3表达明显增多，并促进了整合素介导的细胞与细胞外基质黏附。CXCL12还使细胞移植后位于梗死区的细胞数量增多，且这一作用也与整合素αV/β3有关。结论CXCL12过表达通过促进骨髓基质干细胞整合素αV/β3表达提高了移植干细胞黏附和增殖能力，有利于骨髓基质干细胞移植后在心肌梗死区域的生长和分化。

CXCL12 Chemokine Mediates Mesenchymal Stem Cell Adhesion and Proliferation throughαV andβ3 Integrins

Abstract Background The identification of mesenchymal stem cells (MSCs) have provided exciting prospects for cell-based regeneration after myocardic infraction.However cell therapy have inherent limitations such as low sur- vival rate of transplanted cells and insufficient cell number.It is known that cell-matrix adhesion plays a key role in cell proliferation,differentia-tion and survival,and chemokine CXCL12 may involvedin these prcesses.Thus we transfected mesenchymalstem cells with CXCL12 for local secretion of CXCL12 and then explored CXCL12 triggered adhesion of mesenchymal stem cells to extracellular matrix proteins.Methods Mesenchymal stem cells was transfected with CXCL12.αV andβ3 integrins content was evaluated by Western blot analysis. Cell adhesion to extracellular matrix was examined in-vitro and cell prolife-ration after transplantation in-vivo. Results Transfection of CXCL12 resulted in increased CXCL12 in situ.Increased CXCL12 induced elevated adhesion to fibronectin in-vitro and higher survival invivo.CXCL12 mediated adhesion and proliferation was established by αV andβ3 integrin subunits.Conclusions Che- moattractive mechanisms are involved in adhesion processes of mesenchymal stem cells.Increased CXCL12 leads to enhanced expression of αV andβ3 inte- grins,which may augment cell survival,proliferation and differrentiation.