VCAM-1修饰人脐血基质细胞对造血干／祖细胞扩增作用的实验研究
摘要
AIM: To investigate the effect of vascular cell adhesion molecule-1 (VCAM-1) modified human umbilical cord blood stromal cells (hUCBSCs) on the expansion of hematopoietie stem cells/progenitor cells in vitro. METHODS: After the VCAM-1-pcDNA3.1(+) eukaryotic expression vector was constructed successfully, the recombinant vector was transfected into hUCBSCs via liposome mediation. The expression of the VCAM-1 was detected by semiquantitative RT-PCR and immunocytochemistry. The expansion abilities of hematopoietie cell in vitro under different conditions were compared, including cytokine stimulation, hUCBSCs feeder layer and VCAM-1 modified hUCBSCs feeder layer etc. The effect on hematopoietic reconstitution of different expanded hematopoietic cell groups was compared after CFU-GM, CFU-E and CFU-Mg semi-solid culture were proceed, respectively. RESULTS: The positive clone and Neo(superscript R) gene detection proved that recombinant vector had been transfected into hUCBSCs. The results of semiquantitative RT-PCR and immunocytochemistry manifested that VCAM-1 was high expressed not only at transcriptional level in the stable-transfected hUCBSCs (P＜0.05), but also on the membrane of hUCBSCs (P＜0.05). VCAM-1 modified hUCBSCs feeder layer was used for expansion of CD34(superscript +) cells. It expanded CFU-Mg more effectively than untransfected hUCBSCs did (P＜0.05). CONCLUSION: VCAM-1 modified human umbilical cord blood stromal cells could be useful for expansion of hematopoietie stem/progenitor cells in vitro. It shows that VCAM-1 modified hUCBSCs has potential capability on supportting hematopoiesis.