Placental-Derived Stem Cells: Potential Clinical Applications

Abstract

Placental-derived stem cells are easily accessible and do not have many of the limitations of embryonic stem cells and their derivatives for use in clinical trials. Preclinical animal studies using amnion and, more recently, human amnion epithelial cells (hAECs) have provided evidence of many exciting potential clinical applications. We have characterized hAECs derived from term gestational tissues and investigated their potential application in the treatment of adult and perinatal lung injury. Studies by our group have shown that hAECs display key features of pluripotent stem cells. They do not form teratomas after transplantation into the testes of immunodeficient mice, and they have restricted expression of major histocompatibility antigens in vitro. hAECs also appear to suppress lymphocyte proliferation. Collectively, these findings indicate that hAECs may elicit minimal immune recognition following transplantation to an allogeneic recipient in their native form. Our observations on the reparative effects of hAECs in adult models of lung injury have encouraged us to investigate their potential use as a cellular therapy in the treatment of bronchopulmonary dysplasia and respiratory distress syndrome of preterm infants. In an in utero ventilation model in fetal sheep, our preliminary results indicate that administration of hAECs reduces inflammation and fibrosis, thus providing a potential novel cellular therapy in the treatment of the very preterm infant. Our research on multipotential amnion-derived epithelial stem cells may well revolutionize the approach to the use of stem cells in clinical therapies.