Amniotic fluid collected from vaginal birth as a source of stem cells for clinical applications and disease modeling

IMPORTANCE:  Amniotic fluid is a promising source of autologous cells for disease modeling, drug screening, and regenerative medicine applications. However, current methods of collecting amniotic fluid are invasive, and samples are limited to pregnancies that require amniocentesis or cesarean section. OBJECTIVE:  The purpose of this study was to determine whether amniotic fluid cells could be isolated and cultured from amniotic fluid collected during vaginal deliveries. INTERVENTION:  Amniotic fluid samples were obtained during delivery of 4 neonates, 3 of which had been prenatally diagnosed with hypoplastic left heart syndrome (HLHS) in utero. Adherent amniotic fluid cells were assessed for maternal cell contamination, proliferation rate, surface marker expression, and differentiation potential. Amniotic fluid cells were also reprogrammed to induced pluripotent stem cells (iPSCs) and differentiated into functional cardiomyocytes. RESULTS: Amniotic fluid cells collected from vaginal deliveries showed similar surface marker phenotype and differentiation characteristics to amniotic fluid-derived mesenchymal stem cells collected from amniocentesis and cesarean section. Amniotic fluid cells collected during vaginal births of both neonates with HLHS and one neonate with typical heart geometry could be reprogrammed to iPSCs and differentiated to a cardiac lineage with high efficiency. Conclusions and Relevence: These findings suggest that amniotic fluid collected from vaginal births is a readily available source of patient-specific stem cells for banking, in vitro disease modeling, and regenerative medicine applications.