Bayrak-Toydemir Pinar, Pergament Eugene, Fiddler Morris
Reprogenetics Research, Inc., Chicago, Illinois, USA.
Prenat Diagn. 2003 Aug;23(8):619-24. doi: 10.1002/pd.656.
The objectives of this study were to enhance and apply a simple system capable of testing the capacity of putative, gender-independent fetal cell markers, individually and in combination, to discriminate between fetal and maternal cells.
Chorionic villi tissue obtained from 25 male pregnancies at 10 to 12 weeks' gestation served as the experimental group. Following removal of villi pieces for clinical use, unattached cells were collected by centrifugation of the CVS fluid, fixed in the tube, and used as a source of mixed fetal and maternal cells. Blood obtained from a fetus at 13 weeks' gestation served as a positive control. Peripheral blood from two adult males served as negative controls. Antibodies to three possible fetal markers were tested using immunohistochemical techniques: anti-Flk-1, anti-epsilon globin, and anti-CD71. Each antibody was used alone and in combination in conjunction with fluorescent in situ hybridization (FISH) of X and Y chromosomes to confirm that positively stained cells were in fact fetal in origin.
On CVS samples, the average predictive value for anti-Flk-1 was 35.8%, 76.2% for anti-CD71, and 90.5% for anti-epsilon. The combination of anti-epsilon and anti-CD71 antibodies identifying a fetal cell was 87.2% and the combined use of single and double antibodies gave a value of 82.7%. The combination of anti-epsilon globin and anti-CD71 increased the sensitivity of identifying pure fetal blood cells from 63%, for anti-epsilon alone, and 67%, for anti-CD71 alone, to 86%.
Although anti-Flk-1 has been reported to be a successful marker of fetal cells, the results in this test system did not support this finding. This work supports the use of CVS washings containing both fetal and maternal cells as a viable test system for assessing antigenic markers. The combination of anti-CD71 and anti-epsilon as fetal identifiers may increase the chances of identifying a fetal cell without compromising the predictive value.
本研究的目的是改进并应用一个简单的系统，该系统能够单独或联合检测假定的、与性别无关的胎儿细胞标志物区分胎儿细胞和母体细胞的能力。
从25例妊娠10至12周的男性胎儿的绒毛组织中获取样本作为实验组。在取走用于临床的绒毛组织块后，通过对绒毛取样液进行离心收集未附着的细胞，固定于试管中，并用作混合胎儿细胞和母体细胞的来源。妊娠13周胎儿的血液用作阳性对照。两名成年男性的外周血用作阴性对照。使用免疫组化技术检测针对三种可能的胎儿标志物的抗体：抗Flk-1、抗ε珠蛋白和抗CD71。每种抗体单独及联合使用，并结合X和Y染色体的荧光原位杂交（FISH），以确认阳性染色的细胞实际上源自胎儿。
在绒毛取样样本上，抗Flk-1的平均预测值为35.8%，抗CD71为76.2%，抗ε为90.5%。抗ε和抗CD71抗体联合识别胎儿细胞的比例为87.2%，单抗体和双抗体联合使用的值为82.7%。抗ε珠蛋白和抗CD71联合使用将识别纯胎儿血细胞的灵敏度从单独使用抗ε时的63%和单独使用抗CD71时的67%提高到了86%。
尽管有报道称抗Flk-1是胎儿细胞的成功标志物，但本测试系统中的结果并不支持这一发现。这项工作支持将含有胎儿细胞和母体细胞的绒毛取样冲洗液用作评估抗原标志物的可行测试系统。抗CD71和抗ε联合作为胎儿识别物可能会增加识别胎儿细胞的机会，同时不影响预测值。
