Cervera Aurea, Lillo Rosa, García-Sánchez Félix, Madero Luis, Madero Rosario, Vicario José L
Service of Pediatrics, Hospital de Móstoles, Móstoles, Madrid, Spain.
Am J Hematol. 2006 Jun;81(6):397-410. doi: 10.1002/ajh.20598.
The aim of this study was to characterize the lymphocyte and the hematopoietic stem and progenitor cell (HPC) subsets of cryopreserved premature cord blood (PCB) compared to term cord blood (TCB) by flow cytometry, to study the influence of birth conditions, and to assess its availability for transplantation.
Four-color flow cytometric analysis was performed on 43 PCB and 40 TCB cryopreserved samples using a panel of 24 different mAbs, directed against lymphoid and HPC surface markers. The CB volume was estimated by the weight of the newborn to determine the absolute MNC and CD34(+) cell content/CB sample. Clinical and obstetrical data were recovered. Statistical comparisons and a multiple regression analysis were performed.
No consistent differences were found in the mononuclear cell (MNC) or CD34(+) cell concentration (x10(6)/L) between PCB and TCB. The percentage of primitive HPC (CD34(+)CD38(-), CD34(+)CD38(-)CD90(-)HLA-DR(-), CD34(+)CD38(-)CD90(-)HLA-DR(+)) and primitive lymphoid progenitors (CD34(+)CD7(+), CD34(+)CD7(+)CD19(-)CD117(-)) were higher in PCB than in TCB. Correspondingly, TCB had an increased percentage of committed HPC. No sample of PCB contained >2 x 10(7) MNC/kg (and only 48% had >1 x 10(5) CD34(+) cells) for a recipient of 20 kg body wt, as the minimum threshold recommended for CB transplantation. Obstetrical factors modulated mainly lymphocyte subsets and fewer HPC subpopulations. Acute fetal distress increased CD34(+) cells, especially the immature subsets. Maternal treatment with dexamethasone and intrauterine growth retardation decreased CD3(+) cells. No other obstetrical factors played a detrimental effect on CB cells if used for transplantation.
PCB is richer in immature cells both in lymphocyte and HPC populations, and its use for transplantation, at least in special cases, should be reconsidered.
本研究旨在通过流式细胞术对冷冻保存的早产脐带血（PCB）与足月脐带血（TCB）的淋巴细胞以及造血干细胞和祖细胞（HPC）亚群进行特征分析，研究出生条件的影响，并评估其移植可用性。
使用一组针对淋巴样和HPC表面标志物的24种不同单克隆抗体（mAb），对43份PCB和40份TCB冷冻保存样本进行四色流式细胞术分析。通过新生儿体重估算脐带血体积，以确定每个脐带血样本中的绝对单核细胞（MNC）和CD34(+)细胞含量。收集临床和产科数据。进行统计比较和多元回归分析。
PCB和TCB之间在单核细胞（MNC）或CD34(+)细胞浓度（x10(6)/L）方面未发现一致差异。PCB中原始HPC（CD34(+)CD38(-)、CD34(+)CD38(-)CD90(-)HLA-DR(-)、CD34(+)CD38(-)CD90(-)HLA-DR(+)）和原始淋巴样祖细胞（CD34(+)CD7(+)、CD34(+)CD7(+)CD19(-)CD117(-)）的百分比高于TCB。相应地，TCB中定向HPC的百分比增加。对于体重20 kg的受体，没有一份PCB样本含有>2 x 10(7) MNC/kg（只有48%的样本含有>1 x 10(5) CD34(+)细胞），这是脐带血移植推荐的最低阈值。产科因素主要调节淋巴细胞亚群，对HPC亚群的调节较少。急性胎儿窘迫会增加CD34(+)细胞，尤其是未成熟亚群。母亲使用地塞米松治疗和宫内生长迟缓会降低CD3(+)细胞。如果用于移植，没有其他产科因素对脐带血细胞产生不利影响。
PCB在淋巴细胞和HPC群体中未成熟细胞更丰富，至少在特殊情况下，应重新考虑将其用于移植。
