Culture of cells from maternal circulation, in conditions favoring fetal endothelial cell expansion, does not facilitate the preferential expansion of circulating fetal cells.

Objectives: To establish optimal culture conditions for fetal endothelial cells, and determine whether these can be used for preferential expansion of fetal cells from maternal blood.

Methods: Human adult microvascular and umbilical vein endothelial cells were cultured in the presence of colony-stimulating factor-1 (CSF-1), placental growth factor (PlGF), and transforming growth factor-beta1 (TGF-beta1). The effect of each cytokine was assessed. We expanded peripheral blood mononuclear cells (PBMCs) from 18 pregnant women using the conditions most favorable to fetal cells; in specimens from women carrying male fetuses (n = 9), cell origin was determined by PCR (SRY locus).

Results: The optimal concentrations of CSF-1, PlGF and TGF-beta1 were 10, 100, and 5 ng/ml, respectively. PBMCs from maternal blood expanded in the presence or absence of the cytokines; PCR analysis showed no Y sequences in cultured maternal samples.

Conclusion: Optimal concentrations of CSF-1, PlGF and TGF-beta1 for preferential expansion of fetal endothelial cells were determined in model cultures. However, when these conditions were applied to maternal blood samples, no fetal cells could be detected based on PCR for SRY in women carrying male fetuses.