title: Simultaneous immunophenotyping and FISH on fetal cells from maternal blood.
abstract: Current methods for the prenatal diagnosis of genetic disorders from fetal cells in the maternal circulation are restricted by maternal cell contamination and therefore must rely on the presence of features (such as Y-specific DNA sequences) absent from maternal cells. We have used density gradient centrifugation and magnetic-activated cell sorting to enrich maternal blood samples for fetal nucleated red cells. Mouse monoclonal antibodies for CD45 and CD32 were used to reduce the proportion of leukocytes. Unequivocal identification of fetal cells was achieved using an immunophenotypic test for fetal hemoglobin that allowed the simultaneous application of a diagnostic FISH analysis with chromosome-specific DNA probes. A positive diagnosis of female fetal sex (among other diagnoses) is thus possible even in the presence of an excess of maternal cells. The method, which appears to represent an advance over previous techniques, has considerable application in the development of noninvasive prenatal diagnosis from maternal blood.
authors.affiliation: Department of Pathology, Cambridge University, United Kingdom.
authors.forename: M A
authors.initials: MA
authors.lastname: Ferguson-Smith
authors.forename: Y L
authors.initials: YL
authors.lastname: Zheng
authors.forename: N P
authors.initials: NP
authors.lastname: Carter
mesh_terms: D001773:Blood Cells / Q000166:cytology; D015342:DNA Probes; D005260:Female; D006801:Humans; D018189:Immunomagnetic Separation; D016130:Immunophenotyping; D017404:In Situ Hybridization, Fluorescence / Q000379:methods*; D017493:Leukocyte Common Antigens / Q000032:analysis; D008280:Magnetics; D008297:Male; D008431:Maternal-Fetal Exchange; D011247:Pregnancy / Q000097:blood*; D017452:Receptors, IgG / Q000032:analysis; D012732:Sex Determination Analysis
chemical_list: D015342:DNA Probes; D017452:Receptors, IgG; D017493:Leukocyte Common Antigens