Trophoblast‐like cells sorted from peripheral maternal blood using flow cytometry: A multiparametric study involving transmission electron microscopy and fetal dna amplification

Abstract

Three monoclonal antibodies (MAbs) against trophoblast (GB17, GB21, and GB25) and flow cytometry were used to sort trophoblast-like cells (TLCs) from peripheral blood of pregnant women. Sorted TLCs were processed for electron microscopy and fetal DNA amplification of the Y-specific sequences from mothers carrying male fetuses. At the ultra-structural level, most of the nucleated cells had the morphology of leucocytes, suggesting maternal contaminants, and we did not find the characteristic features of the free intervillous trophoblast cells. Nevertheless, polymerase chain reaction (PCR) analysis showed an amplification of Y-specific sequences in two out of three samples of sorted TLCs. These results suggest that besides the maternal leucocytes, sufficient trophoblast nucleated fetal cells can be obtained using cell enrichment by sorting. This sensitive method holds promise for non-invasive prenatal diagnosis of fetal sex and if sufficient Y(positive) nuclei are found, for the diagnosis of selected numerical chromosome abnormalities.

Demonstration of a Tissue Factor Pathway Inhibitor 2 Messenger RNA Synthesis by Pure Villous Cytotrophoblast Cells Isolated from Term Human Placentas1

“…GB25, a monoclonal antibody specific to the villous trophoblast [32,33], was used to stain all cells, as demonstrated by flow cytometry analysis. In contrast, no staining was observed with the anti-CD9 monoclonal antibody, confirming the absence of contaminating platelets, B and T lymphocytes, polynuclear cells, endothelial cells, epithelial and vascular smooth muscle cells [33], and extravillous trophoblast cells [34].…”

Remarkable placenta

“…Small portions of this syncytium bud off and reach the maternal lung through the intervillous circulation. Most of these deported syncytial buds are destroyed here; a few are passed, however, and these are being sought in the maternal peripheral blood for genetic diagnosis of the fetus (Bruch et al, 1991). As intervillous circulation is hampered occasionally by disease states (preeclampsia), there is less fluid transfer to the villous circulation; the consequence of this is fetal growth retardation.…”

Prenatal diagnosis using fetal cells in the maternal circulation

“…26 Camashella et al 2 7 Lo et al 2 8 Weier et al 29 Ganshirt-Ahlert et al 30 Wessman et al 31 Hamada et al 32 Thomas et al 33 PCR 24 Adinolfi et al 35 Mueller et al 34 Bruch et al 36 Cacheux et al 3 7 Hawes et al 38 McAb H315 Trophoblast cells Trophoblast cells, although the first to be described in the maternal circulation, are difficult to enrich. There are three kinds of nucleated fetal cells which are believed to be present in maternal circulation: trophoblast cells, lymphocytes and nucleated erythrocytes.…”