FL对脐血造血细胞长期液体培养的影响

The Influence of FL on in vitro Expansion of Hematopoietic Cells from Cord Blood in Long term Liquid CulturesThis Work Was Partially

用脐血进行干细胞移植有许多优点，但有一个主要的缺点是可获得的细胞数量有限，因此脐血干细胞的体外扩增对于其临床应用具有重要意义。考察了Ｆｌｔ３配体（ＦＬ）和干细胞因子（ＳＣＦ）、白介素３（ＩＬ３）、ＩＬ６、粒细胞集落刺激因子（ＧＣＳＦ）、粒细胞巨噬细胞集落刺激因子（ＧＭＣＳＦ）的组合对脐血细胞扩增和分化的影响。培养４２ｄ，总细胞最多扩增了３８５３０±１６３．５１倍（ＦＬ＋ＳＣＦ＋ＧＣＳＦ＋ＧＭＣＳＦ），粒细胞巨噬细胞集落形成单位（ＣＦＵＧＭ）在第２８天达到最高，最高扩增了４０９５２±１８９５０倍（ＦＬ＋ＳＣＦ＋ＩＬ３＋ＩＬ６）。ＦＬ与ＳＣＦ等细胞因子具有协同作用，对所有考察的细胞因子组合中，加入ＦＬ都使总细胞和ＣＦＵＧＭ的扩增倍数增加。ＦＬ＋ＳＣＦ培养的总细胞扩增最小，而ＣＦＵＧＭ长时间保持在较高水平，表明这ＦＬ和ＳＣＦ有利于保持造血干细胞的活性，防止细胞分化。在存在ＧＣＳＦ和ＧＭＣＳＦ的培养中，总细胞获得了最大的扩增，但ＣＦＵＧＭ达到最大后很快下降至０，表明ＧＣＳＦ和ＧＭＣＳＦ促进了细胞的分化。结果提示，细胞因子组合对脐血造血细胞的扩增和分化具有重要的作用，ＦＬ和ＳＣ?

Though use of umbilical cord blood (CB) for stem cell transplantation has a number of advantages, a major disadvantage is the rathar low cell number available. Therefore, in vitro expansion were proposed to overcome this limitation. In this paper the effect of flt 3 ligand (FL), stem cell factor(SCF), interleukin(IL) 3, IL 6, granulocyte colony stimulating factor(G CSF) and granulocyte monocyte colony stimulating factor(GM CSF) on long term in vivo expansion and differentiation of cord blood hematopoietic cells was investigated. In the culture containing FL+SCF+G CSF+GM CSF,the total cell expansion ratios reached the maximum (385.30±163.51 fold) at 28 day, whereas grown with FL+SCF+IL 3+IL 6, CFU GM expansion ratios reached a plateau(409.52±189.50 flod) at 28 day. FL synergized with SCF and other cytokines. In all the conditions investigated, the culture with FL obtained an increase of both total cell and CFU GM expansion. Combination of FL+SCF don't benefit to the proliferation of the total cells, however, the expansion of CFU GM keep at high level. Apparently both cytokines keep the activities of stem/progenitor cells and hamper differentiation. In the presence of G CSF and GM CSF, total cells enhanced quickly, and had the most. expansion of total cells in comparison with other combinations. However, CFU GM output peaked at 18 day and subsequently dropped to 0 promptly, suggesting that G CSF and GM CSF inspired differentiation.