Targeted quantitative amniotic cell profiling: A potential diagnostic tool in the prenatal management of neural tube defects

PurposeWe sought to determine whether amniotic cell profiles correlate quantitatively with neural tube defect (NTD) type and/or size.MethodsSprague–Dawley fetuses exposed to retinoic acid (n = 61) underwent amniotic fluid sample procurement before term. Samples were analyzed by flow cytometry for the presence of cells concomitantly expressing Nestin and Sox-2 (neural stem cells, aNSCs), and cells concomitantly expressing CD29 and CD44 (mesenchymal stem cells, aMSCs). Statistical analysis included ANOVA and post-hoc Bonferroni adjusted comparisons (P < 0.05).ResultsThere was a statistically significant increase in the proportion of aNSCs in fetuses with spina bifida (6.78% ± 1.87%) when compared to those with exencephaly (0.64% ± 0.23%) or with both spina bifida and exencephaly (0.22% ± 0.09%). Conversely, there was a statistically significant decrease in the proportion of aMSCs in fetuses with exencephaly, either isolated (1.09% ± 0.42%) or in combination defects (2.37% ± 0.63%) when compared with normal fetuses (8.83% ± 1.38%). In fetuses with isolated exencephaly, there was a statistically significant inverse correlation between the proportion of aNSCs and defect size.ConclusionsThe proportions of neural and mesenchymal stem cells in the amniotic fluid correlate with the type and size of experimental NTDs. Targeted quantitative amniotic cell profiling may become a useful diagnostic tool in the prenatal evaluation of these anomalies.