Seppo Antti, Frisova Veronika, Ichetovkin Ilia, Kim Youngmin, Evans Mark I, Antsaklis Aristeidis, Nicolaides Kypros H, Tafas Triantafyllos, Tsipouras Petros, Kilpatrick Michael W
Ikonisys Inc, 5 Science Park, New Haven, CT 06511, USA.
Prenat Diagn. 2008 Sep;28(9):815-21. doi: 10.1002/pd.1987.
As fetal cells can be indisputably identified through detection of Y FISH signals, we utilized an automated microscopy system developed to identify and enumerate cells bearing X and Y FISH signals. We further investigated the potential of fetal hemoglobin expression as a gender independent marker for automated identification of fetal cells.
For FISH-based scanning, verified fetal cells were identified based on the presence of a single X-signal and individual signals for each of the two Y FISH probes. For cell identification based on fetal hemoglobin expression, putative fetal cells were verified based on the presence of signals for anti-gamma or anti-epsilon globin antibody, and FISH signals for the X- and Y- chromosomes.
Fetal cells were identified, by FISH-based scanning, in 28 of the 29 maternal samples from pregnancies with male fetuses. Simple density gradient centrifugation achieved a 3- to 5-fold increase in the number of fetal cells detected.
Automated microscopy identified fetal cells in both first and second trimester maternal blood samples. Although we were unable to detect fetal erythroblasts in numbers sufficient for clinical diagnosis, the ability to reliably detect fetal cells by FISH-based scanning opens the possibility for prenatal detection of chromosomal aberrations utilizing circulating fetal cells.
由于通过检测Y FISH信号能够明确识别胎儿细胞，我们使用了一种开发用于识别和计数带有X和Y FISH信号细胞的自动显微镜系统。我们进一步研究了胎儿血红蛋白表达作为性别独立标记用于自动识别胎儿细胞的潜力。
对于基于FISH的扫描，根据单个X信号以及两个Y FISH探针各自的单个信号来识别经过验证的胎儿细胞。对于基于胎儿血红蛋白表达的细胞识别，根据抗γ或抗ε珠蛋白抗体的信号以及X和Y染色体的FISH信号来验证假定的胎儿细胞。
在29例怀有男性胎儿的孕妇样本中，通过基于FISH的扫描在28例样本中识别出了胎儿细胞。简单的密度梯度离心法使检测到的胎儿细胞数量增加了3至5倍。
自动显微镜在孕早期和孕中期孕妇血样中均识别出了胎儿细胞。尽管我们未能检测到数量足以用于临床诊断的胎儿成红细胞，但通过基于FISH的扫描可靠地检测胎儿细胞的能力为利用循环胎儿细胞进行产前染色体畸变检测开辟了可能性。
