Isolation of Fetal Cells from Maternal Blood - From Fact to Reality

(Abstract presented at IFPA 2009, Adelaide)

Ripudaman Singh*, Andreas Eckelt, Ann Birte Bro, Britta Christensen, Hanne Skannerup, Helle Kristensen, Kristine Møller, Lotte Hatt, Maja B. Kristensen, Marianne Rasmussen, Marie Brinch, Otto Bjerg Hausgaard, Rune Hoff Lauridsen, Simon Tabi  Arrey, Steen Kølvraa, Trine Overgaard Petersen.

FCMB ApS. Tysklandsvej 7. Vejle 7100. Denmark. *Email: This e-mail address is being protected from spambots. You need JavaScript enabled to view it

“Foreign cells from the fetus do circulate in mother’s blood” – This was the fact known to the biologists since late 19th century when Georg Schmorl first described the presence of trophoblast sprouts in the lungs of women who died of eclampsia. It has taken biologists another century to decipher methods to isolate the rare fetal cells from maternal circulation, which have great potential in non-invasive prenatal diagnosis. We have developed a novel method of consistently separating rare fetal cells from maternal circulation. Intravenous blood was collected from pregnant women (gestation age 11 to 14 weeks). Gender of the fetus was checked by performing Y specific PCR. 24ml blood from mothers carrying male fetus was prepared for antibody labeling using a proprietary preparation technology. The cells were then incubated with ‘FCMB cocktail-1’ antibodies, fetal cells isolated by magnetic cell sorting and later identified by automated scanning of XY-FISH. 754 fetal cells, on an average of 1cell/5ml of whole blood, were isolated. Some cells were rehybridized using reverse-colour XY-FISH to confirm their fetal origin. 100 fetal cells (in a biological replicate of 2) were used to prepare cDNA for microarray analysis. A comparison of the array data from the fetal cells with the control maternal blood cells gave us a clear indication of the unique markers that are expressed in the fetal cells. We have based this knowledge to further develop a method for isolation/detection of fetal cells from maternal circulation. We have also been successful in staining fetal cells with a cocktail of intracellular antibodies. This has further enhanced our ability to perform a gender-free isolation/detection of fetal cells from maternal blood. Taking a lead from our ability to successfully and consistently isolate fetal cells, we are now in the process of doing a feasibility study on high risk pregnancies.