Date of Award
D. Randall Armant
Trophoblast cells migrate from the placenta into the endocervical canal early in the first trimester and can be collected non-invasively by transcervical sampling (TCS), potentially providing fetal DNA for prenatal genetic diagnosis. Experiments were conducted to separate fetal cells from maternal cells within the TCS specimens and use the fetal cells to perform genetic analysis. Trophoblast cells were efficiently isolated from TCS specimens during weeks 5-18 of gestation using HLA-G antibody coupled to magnetic nanoparticles. Immunofluorescence microscopy revealed that 99% of isolated cells expressed the chorionic gonadotropin β subunit (β-CG), while the non-bound cell fraction expressed none. Immunomagnetically isolated cells from 20 patient specimens were used to determine fetal gender in single cell assays, amplifying sequences in genes on the X (DMD) and Y (SRY) chromosomes by multiplex polymerase chain reaction (PCR). Of 270 total cells, PCR products were detected in 256 cells and identified gender (11 male; 9 female) without error. PCR-based genetic testing is highly reliable as early as week 5 of gestation after immunomagnetic isolation of extravillous trophoblast cells obtained by TCS.
Bajpayee, Swati, "Prenatal Genetic Diagnosis Using Transcervically Derived and Immunomagnetically Isolated Trophoblast Cells" (2012). Honors College Theses. 7.