A new marker set that identifies fetal cells in maternal circulation with high specificity

ABSTRACT Objective Fetal cells from the maternal circulation (FCMBs) have the potential to replace cells from amniotic fluid or chorionic villi in a diagnosis of common chromosomal aneuploidies. Good markers for enrichment and identification are lacking. Method Blood samples from 78 normal pregnancies were used for testing the marker‐set CD105 and CD141 for fetal cell enrichment. Fetal cell candidates were subsequently stained by a cocktail of cytokeratin antibodies, and the gender of the fetal cells was explored by fluorescence in situ hybridization (FISH) of the X and Y chromosomes. Results Fetal cell candidates could be detected in 91% of the samples, and in 85% of the samples, it was possible to obtain X and Y chromosomal FISH results for gender determination. The concordance between gender determined by FISH on fetal cells in maternal blood and gender found at birth reached 100% if three or more fetal cells with FISH signals could be found in a sample. Conclusion The marker set identifies fetal cells with specificity high enough to make cell‐based noninvasive prenatal diagnosis realistic. © 2014 John Wiley & Sons, Ltd. What's already known about this topic?Optimal markers for enrichment and detection of sufficient numbers of fetal cells from maternal blood are lacking if fetal cells are to be used in noninvasive prenatal diagnosis.Fetal extravillous trophoblasts (EVTs) are present in the maternal blood circulation, but enrichment and specific identification have been suboptimal. What does this study add?This study presents a new marker set for enrichment and identification of fetal EVT cells.Fetal EVT cells can be detected with a high specificity of 96%.