ISOLATING FETAL NUCLEATED RED-BLOOD-CELLS FROM MATERNAL BLOOD - THE BAYLOR EXPERIENCE, 1995

In our previous work we have isolated fetal cells from maternal blood and used fluorescent in situ hybridization (FISH) for chromosome-speci fic probes to detect aneuploidy. Current efforts in the Baylor College of Medicine programme are focusing on obtaining consistency in flow-s orting methodology and on determining sensitivity and specificity. To this end, systematic evaluation of Eve glycophorin A (gly A) antibodie s all produced agglutination, leading us to abandon the use of gly A a ntibodies for positive selection of fetal cells. Conversely, we have f ound LDS-751 to be useful for nuclear selection. CD45 negative selecti on can best be accomplished by the use of flasks coated with goat anti bodies against mouse antibodies. Positive selection by flow sorting fo r either CD71(+) cells or gamma-globin-positive cells seems to be succ essful. Using these two approaches, we have recently detected male (fe tal) cells in pregnancies in which the fetus was 46,XY in 10 of 18 and in 12 of 14 cases, respectively.