目的 探讨CD133（AC133）在急性白血病（AL）中的表达及其意义。方法 采用三色荧光流式细胞术测定76 例AL患者白血病细胞膜上CD133的表达；采用半定量逆转录2聚合酶链反应（RT-PCR）方法测定CD133mRNA表达。结果 ①正常对照和AL患者的CD133mRNA表达与CD133蛋白表达相一致，AL患者CD133表达水平显著高于正常对照。②AL患者CD133及CD133mRNA高表达阳性率分别为42.1%和46.1%。急性髓系白血病（AML）M3患者CD133均高表达阴性，AML和急性淋巴细胞白血病（ALL）的CD133高表达率分别为43.4%和38.1%，差异无显著性。AML-M4CD133高表达阳性率显著高于其它AML亚型，而T-ALL和B-ALL的CD133高表达率分别为20.0%和43.7%，差异也无显著性。③AML患者骨髓细胞CD133表达与CD34、HLA-DR显著相关，ALL患者骨髓细胞CD133表达与CD34无关。④CD133表达与细胞或分子遗传学异常、发病时外周血白细胞数、乳酸脱氢酶水平、多药耐药基因（mdr1）表达及年龄等预后因素无显著相关。⑤CD133高表达阳性组完全缓解（CR）率及总反应（OR）率低于高表达阴性组，但仅有CD34/CD133共高表达阳性组CR率低于阴性组（44.4% vs 71.4%，P<0.05），差异有显著性。结论 AL 患者骨髓细胞CD133表达高于正常对照；检测CD133表达可能有助于AL各亚型的鉴别及疗效判断；CD133/CD34共同高表达可能是AL的一个不良预后因素。

目的 探讨体外扩增对脐血（UCB）造血干P祖细胞（HSPC）原有粘附功能的影响。方法 将从新鲜UCB标本中纯化的CD34+ 细胞接种于无血清、无基质的悬浮扩增体系，分别于培养第7天、第10天和第14天从扩增产物中再次纯化CD34+ 细胞，比较扩增前后CD34+ 细胞表面VLA24（CD49d）、VLA25（CD49e） 、LFA-1 （CD11a） 、Lselectin （CD6-L） 、PECAM-1 （CD31）、ICAM-1 （CD54） 和HCAM（CD44）等归巢相关粘附分子（CAMs）的表达情况，并检测CD34+ 细胞与纤连蛋白（FN）间的自发粘附率和基质细胞来源因子-1（SDF-1）诱导粘附率。结果　①在第14天的培养扩增中，表达上述CAMs的各CD34+ 细胞亚群均有不同程度（15～72倍）的扩增；②扩增后CD34+ 细胞表面粘附分子CD44、CD11a 、CD49e和CD49d的表达与原代CD34+ 细胞持平或高于培养开始时水平，而CD6-L 、CD54和CD31的表达则有不同程度下调；③在前10d的扩增中，CD34+细胞与FN 间的自发粘附率和SDF-1诱导粘附率均呈上升趋势。结论　所建立的短期培养体系不仅可以支持表达重要CAMs 的UCB CD34 + 细胞亚群的有效扩增，而且扩增后的HSPC总体上保持原有的粘附功能。

To investigate the clinically applicable conditions that support substantial expansion of both primitive and more mature hematopoietic cells of umbilical cord blood (UCB) for transplantation in adults, enriched CD34+ cells from 8 fresh UCB samples and 4 expanded UCB products were cultured in defined serum-free medium (QBSF-60) in the presence of a cytokine combination of SCF, Flt-3-ligand (FL), thrombopoietin (TPO), IL-3 for up to 2 weeks. Fresh medium with cytokines was supplemented or exchanged at day 4, day 7, and day 10. The proliferative response was assessed at day 7, day 10, and day 14 by evaluating the following parameters: nucleated cell (NC), clonogenic progenitors (colony-forming unit-granulocyte-macrophage [CFU-GM], burst-forming unit-erythrocyte [BFU-E], CFU-GEMM, and high-proliferative potential colony-forming cell [HPP-CFC]), immunophenotypes (CD34+ cells and CD34+ subpopulations), and LTCIC. Simultaneously numerical expansion of various stem/progenitor cells, including primitive CD34+ CD38- HLA-DR- subpopulation and LTCIC, CD34+ cells, and clonogenic progenitors to mature nucleated cells, were continuously observed during the culture. An average 103.32±71.37×106 CD34+ cells (range 10.12×106-317.9×106) could be obtained from initial 1.72±1.13×106 UCB CD34+ cells after 10-14 days cultured under the described conditions. Sufficient CD341 cells (＞50.0×106) for transplantation in adults would be available in all but one UCB collections after 10-14 days expansion. The expanded CD34+ cells sustained most of the in vitro characteristics of initial unmanipulated CD34+ cells, including clonogenic efficiency (of both primitive and committed progenitors), the proportion of CD34+ CD38-HLA-DR- subpopulation, and the expansion potential. Initial addition of IL-3 to the cocktail of SCF+ FL+ TPO had positive effects on the expansion of both primitive and, especially, the more mature hematopoietic cells. It accelerated the expansion speed and shortened the optimal culture time from 14 days to 10 days. These results indicated that our proposed shortterm culture system, consisting of QBSF-60 serum-free medium with a simple early acting cytokine combination of SCF+ FL+TPO, could substantially support simultaneous expansion of various stem/progenitor cell populations involved in the different phases of engraftment. It would be a clinically applicable protocol for ex vivo expansion of CD34+ UCB cells.