人脐静脉内皮细胞支持体外造血和造血干／祖细胞扩增

目的 :研究人脐静脉内皮细胞 (humanumbilicalveinendothelialcell ,HUVEC)对体外造血和造血干 /祖细胞扩增的支持作用 ,为造血干 /祖细胞体外扩增提供新的实验资料。方法 :用甲基纤维素集落形成实验检测集落形成情况 ,采用HUVEC与脐血单个核细胞和CD34+细胞直接接触共培养的方法观察HUVEC对体外造血和造血干 /祖细胞扩增的支持作用。结果 :HUVEC上清具有集落刺激活性。将HUVEC与脐血单个核细胞直接接触共培养 ,结果表明HUVEC能维持脐血单个核细胞体外存活至少 4周。将脐血CD34+细胞与HUVEC直接接触共培养 ,动态地观察有核细胞扩增倍数、CD34+细胞扩增倍数、CD4 1a+细胞百分比和CFU GM扩增倍数的变化。结果发现 ,有核细胞扩增倍数、CD34+细胞扩增倍数和CD4 1a+细胞百分率均在第 3周达最高 ,分别为 (6 8.1± 14.8)倍、(6 .6± 1.4 )倍和 15.6 % ,而CFU GM扩增倍数则于第 2周达最高 ,为 (5.7± 2 .1)倍。结论 :HUVEC能支持体外造血和造血干 /祖细胞扩增并具有促进巨核系细胞分化的能力

Human umbilical vein endothelial cells support hematopoiesis and expansion of hematopoietic stem/progenitor cells in vitro

Objective: To investigate the role of human umbilical vein endothelial cells (HUVEC) in supporting hematopoiesis and the expansion of hematopoietic stem/progenitor cells in vitro. Methods: According to the fact that HUVEC supernatant has colony stimulating activity shown by methylcellulose colony-forming assay and HUVEC can maintain the survival of mononuclear cells for at least four weeks in vitro, CD34+ cells from umbilical cord blood were seeded with (HUVEC group) or without (control group) HUVEC monolayer. Every week cells were collected and counted, the frequency of CFU-GM was measured by using methylcellulose colony-forming assay, and the percentage of CD34+ and CD41a+ cells was measured by flow cytometry. Results: In control group，all the CD34+ cells died in two weeks. However, in HUVEC group,most nucleated cells and CD34+ cells were expanded by 68.1±14.8 fold and 6.6±1.4 fold，respectively at the third week while CFU-GM expansion reached its peak (5.7±2.1 fold) at the week 2. Moreover, the percentage of CD41a+ cells was enhanced significantly, reaching a maximum (15.6%) at the week 3. Conclusions:HUVEC can support hematopoiesis in vitro and expand the hematopoietic progenitor cells and CD41a+ cells in direct contact coculture.