Gestational tissue such as the placenta, placental membranes and amniotic fluid are untapped reserves of stem cells. Human amniotic fluid has been utilized in prenatal diagnosis for over 70 years. However, there is now evidence that amniotic fluid may have more utility than only as a diagnostic tool and may be a source of a powerful therapy for a multitude of congenital and adult disorders
Recently, researchers have isolated and characterized highly multipotent cells from the amniotic fluid and placental membranes. Amniotic fluid-derived stem cells (AFSC) can be isolated from a small amount of the fluid obtained during amniocentesis, a procedure that is already performed in many pregnancies to screen for congenital abnormalities. Mesenchymal and epithelial stem cells can be obtained from the placenta and placental membranes, which are usually discarded following birth. Epithelial cells from the amnion membrane have been found to be multipotent with low immunogenicity and immunosuppressive functions.
Recently our group demonstrated the isolation of human amniotic epithelial cells (hAECs) using methods suitable for clinical applications. Stem cells derived from the amniotic fluid and placental tissues have been show to differentiate into hematopoietic, osteogenic, chondrogenic, adipogenic, endothelial, myogenic, neural, and lung cells among other cell lineages. These cells also possess potent immunomodulatory properties, such as production of anti-inflammatory factors as well as interacting with immune cells to modulate the immune response. These properties make amniotic fluid and human amniotic epithelial cells an attractive alternative for cell therapy.