Detection of circulating fetal cells utilizing automated microscopy: potential for noninvasive prenatal diagnosis of chromosomal aneuploidies.
OBJECTIVE
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.


METHODS
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.


RESULTS
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.


CONCLUSIONS
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.
Seppo
Antti
A
Ikonisys Inc, 5 Science Park, New Haven, CT 06511, USA.
Frisova
Veronika
V
Ichetovkin
Ilia
I
Kim
Youngmin
Y
Evans
Mark I
MI
Antsaklis
Aristeidis
A
Nicolaides
Kypros H
KH
Tafas
Triantafyllos
T
Tsipouras
Petros
P
Kilpatrick
Michael W
MW
D000782:Aneuploidy; D041321:Chromosomes, Human, X; D041322:Chromosomes, Human, Y; D005260:Female; D005331:Fetomaternal Transfusion / Q000097:blood*; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D008297:Male; D008856:Microscopy, Fluorescence; D011247:Pregnancy; D011261:Pregnancy Trimester, First; D011296:Prenatal Diagnosis / Q000379:methods*; D012732:Sex Determination Analysis; D055547:epsilon-Globins / Q000302:isolation & purification; D055545:gamma-Globins / Q000302:isolation & purification
D055547:epsilon-Globins; D055545:gamma-Globins