Permanent expression of midbrain dopaminergic neurons traits in differentiated amniotic epithelial cells.

ABSTRACT

Amniotic epithelial cells (AECs) have been the subject of interest due to their stem cells characteristics. Pluripotency, lack of teratoma formation, low immunogenicity and no ethical issues make them an alternative source of stem cells for generation of dopaminergic neurons in vitro. AECs may differentiate into midbrain dopaminergic neurons in the presence of induction factors which trigger pathway naturally occurring in the mesencephalon during embryogenesis. In this study, we examined whether FGF8 and Sonic hedgehog (Shh) can induce AECs to express permanently midbrain dopaminergic neurons traits. We found that fresh isolated AECs temporarily expressed some neural markers which decreased 7 days after culture. Co-treatment of cells with FGF8 and Shh had synergistic effect on expression of TH, DAT, Pax2, Lmx1b and En1. Shh ceased differentiation in dopaminergic state and decreased DßH. HPLC analysis revealed that dopamine was released into the medium upon depolarization, indicating that functional dopaminergic neurons were present in the culture. These results demonstrate that AECs have capability to differentiate into dopaminergic neurons and can be a candidate for cell replacement therapy of Parkinson's disease.