Andrews K, Wienberg J, Ferguson-Smith M A, Rubinsztein D C
Department of Pathology, Cambridge University, U.K.
Prenat Diagn. 1995 Oct;15(10):913-9. doi: 10.1002/pd.1970151006.
The presence of small numbers of fetal nucleated red cells in the maternal circulation has been a stimulus for the development of technologies for non-invasive prenatal genetic analysis. Our laboratory has been assessing the feasibility of density gradient centrifugation followed by magnetic activated cell sorting (MACS) of cells expressing CD32 and CD45, to deplete maternal nucleated blood cells. We have examined the efficiency of each of the steps of this procedure using cord blood from term pregnancies as a source of nucleated red blood cells. Cord blood was shown to contain highly variable numbers of nucleated red cells. Three different density gradients were examined. There was no major difference in the performances of the double and triple gradients. Density gradient centrifugation resulted in enrichments of nucleated red blood cells of about 1000-fold relative to the total cell count. However, it was apparent that the selection of the cell layers which were most enriched for these cells would result in significant losses of nucleated red cells in other layers. MACS sorting of cells using CD45 resulted in white cell depletions ranging from 7 to 34-fold. These data provide a foundation for comparison with other methods and for optimization of the MACS technique.
母体外周血中存在少量胎儿有核红细胞，这推动了无创产前基因分析技术的发展。我们实验室一直在评估密度梯度离心结合对表达CD32和CD45的细胞进行磁性激活细胞分选（MACS）以去除母有核血细胞的可行性。我们使用足月妊娠脐带血作为有核红细胞来源，检验了该程序每个步骤的效率。结果显示脐带血中所含的有核红细胞数量差异很大。我们检测了三种不同的密度梯度。双重梯度和三重梯度的性能没有重大差异。密度梯度离心使有核红细胞相对于总细胞计数富集了约1000倍。然而，很明显，选择这些细胞富集程度最高的细胞层会导致其他层中有核红细胞大量损失。使用CD45对细胞进行MACS分选使白细胞减少了7至34倍。这些数据为与其他方法进行比较以及优化MACS技术提供了基础。
