Biology of human primitive erythroblasts for application in noninvasive prenatal diagnosis

• Published in: Prenatal diagnosis 2018-08, Vol.38 (9), p.673-684
• Main Authors: Huang, Zhou‐Wei, Fong, Chui‐Yee, Gauthaman, Kalamegam, Sukumar, Ponnusamy, Mahyuddin, Aniza P., Barrett, Angela N., Bongso, Ariff, Choolani, Mahesh
• Format: Article
• Language: English
• Subjects: Apoptosis; Biological properties; Biology; Cell culture; Cell surface; Chromatin; Degeneration; Diagnosis; Embryogenesis; Embryonic growth stage; Enucleation; Erythroblasts; Gene expression; Genetic analysis; Gestation; Histology; Medical diagnosis; Nuclei (cytology); Placenta; Prenatal diagnosis; Surface markers; Viability
• ISSN: 0197-3851; 1097-0223
• DOI: 10.1002/pd.5295

Objective Human primitive erythroblasts produced during early embryogenesis have been found in maternal circulation at early gestation and are considered good target cells for noninvasive prenatal diagnosis. We aimed to gain a better understanding of the biology of primitive erythroblasts and maximize their potential utility for noninvasive prenatal diagnosis. Methods Cells were obtained from first trimester human placental tissues. Biological properties including surface antigen composition, differentiation, proliferation, enucleation, and degeneration were studied as gestation progressed. A microdroplet culture system was developed to observe the behavior of these cells in vitro. Results Histology showed that primitive erythroblasts undergo maturation from polychromatic to orthochromatic erythroblasts and can differentiate spontaneously in vitro. Cell surface markers and nuclear gene expression suggest that the cells do not possess stemness properties, despite being primitive in nature. They have limited proliferative activity and highly deacetylated chromatin, but a microdroplet culture system can prolong their viability under normoxic conditions. No apoptosis was seen by 11 weeks' gestation, and there was no enucleation in vitro. Conclusion These properties confirm that viable cells with intact nuclei can be obtained at very early gestation for genetic analysis. What's already known about this topic? Human primitive erythroblasts have been proposed to be the ideal fetal cell type for definitive noninvasive prenatal diagnosis of aneuploidy and single gene disorders. Isolation of these cells is challenging due to limited numbers and lack of cell‐specific surface markers. What does this study add? Human primitive erythroblasts exhibited a lack of “stemness” and lack of enucleation prior to 11 weeks' gestation. These characteristics support their use for NIPD. Their limited proliferation may be due to chromatin condensation, and so it is possible that histone deacetylase inhibitors could drive them back into the proliferative state, overcoming the issue of low cell numbers in maternal blood.