Høgh A M, Hviid T V, Christensen B, Sørensen S, Larsen R D, Smidt-Jensen S, Bang J, Philip J
Department of Clinical Biochemistry 339, Copenhagen University Hospital, H:S Hvidovre Hospital, 30 Kettegaard Allé, DK-2650 Hvidovre, Denmark.
Clin Chem. 2001 Apr;47(4):645-53.
Information about the appearance of gamma-, epsilon-, and zeta-globin mRNAs in fetal erythroblasts during gestation and about the presence and amounts of these mRNAs in pregnant and nonpregnant women is important from the perspective of using these molecules as a marker of fetal erythroblasts. A specific marker is necessary for isolation and identification of fetal nucleated red blood cells from maternal blood samples for use in antenatal diagnosis of fetal genetic or chromosomal abnormalities.
We used a very sensitive reverse transcription-PCR (RT-PCR) method, coamplification analysis of gamma- and epsilon-globin cDNA, and quantitative analysis of gamma-globin mRNA based on competitive RT-PCR to investigate these aspects.
All adult whole-blood samples were negative for epsilon- and zeta-globin mRNA. Analyses of CD71(+) cell fractions showed that specimens from 19 of 20 nonpregnant and 10 of 14 pregnant women (at 9-13 weeks of gestation) were positive for gamma-globin mRNA (Fisher's exact test, P = 0.13), and those from 3 of 20 nonpregnant and 5 of 14 pregnant women were positive for zeta-globin mRNA (Fisher's exact test, P = 0.23). No epsilon-globin mRNA was detected in CD71(+) cell fractions from 1-mL blood samples from adults. CD71(+) cell fractions from eight fetal blood samples (at 17-20 weeks of gestation) were positive for all three globin mRNAs. We found no statistically significant difference between the amounts of gamma-globin mRNA in pregnant and nonpregnant women.
This study indicates that epsilon-globin mRNA might function as a marker for fetal CD71(+) cells early in pregnancy. Although gamma-globin mRNA can be detected in CD71(+) cell fractions from most adults, these transcripts also may be of use because of a marked difference between adult and fetal values.
从将这些分子用作胎儿成红细胞标志物的角度来看，了解孕期胎儿成红细胞中γ-、ε-和ζ-珠蛋白mRNA的出现情况以及这些mRNA在孕妇和非孕妇中的存在情况和数量很重要。从母体血样中分离和鉴定胎儿有核红细胞以用于胎儿遗传或染色体异常的产前诊断需要一种特异性标志物。
我们使用了一种非常灵敏的逆转录-聚合酶链反应（RT-PCR）方法、γ-和ε-珠蛋白cDNA的共扩增分析以及基于竞争性RT-PCR的γ-珠蛋白mRNA定量分析来研究这些方面。
所有成人全血样本的ε-和ζ-珠蛋白mRNA均为阴性。对CD71(+)细胞组分的分析表明，20名非孕妇中的19名以及14名孕妇（妊娠9至13周）中的10名的样本γ-珠蛋白mRNA呈阳性（Fisher精确检验，P = 0.13），20名非孕妇中的3名以及14名孕妇中的5名的样本ζ-珠蛋白mRNA呈阳性（Fisher精确检验，P = 0.23）。在来自成人的1 mL血样的CD71(+)细胞组分中未检测到ε-珠蛋白mRNA。来自8份胎儿血样（妊娠17至20周）的CD71(+)细胞组分中所有三种珠蛋白mRNA均呈阳性。我们发现孕妇和非孕妇中γ-珠蛋白mRNA的量没有统计学上的显著差异。
本研究表明，ε-珠蛋白mRNA可能在妊娠早期作为胎儿CD71(+)细胞的标志物发挥作用。尽管在大多数成人的CD71(+)细胞组分中可检测到γ-珠蛋白mRNA，但由于成人和胎儿的值存在显著差异，这些转录本也可能有用。
