Human placenta-derived stem cells (PDSCs)

Placenta is an organ within the uterus that provides the mechanical and physiological connection between fetal and maternal tissues for the nutrition, respiration and excretion of the fetus. It also functions as a gland secreting various hormones and acts as an immunological barrier between the fetus and the maternal immune system. The placenta besides supporting fetal development, may also represent a valuable, promising and significant reservoir of stem cells. Stem cells derived from placental layers and membranes (amnion, chorione, decidual) have shown high proliferative capacity and differentiation into multilineage cells, demonstrating even stronger capacity than those shown for bone marrow-derived stem cells. PDSCs display a fibroblastoid phenotype upon adherence and express the range of markers used to characterise MSCs. Since the placenta is fundamental for maintaining fetomaternal tolerance during pregnancy, the cells present in placental tissue may have immunomodulatory characteristics; this aspect contributes to make cells from placenta good candidates for possible use in cell therapy approaches, with the possibility of providing cells that display immunological properties that would allow their use in an all-transplantation setting. Currently there are several ongoing clinical trials which are using specific formulations of placenta-derived adherent cells for peripheral artery disease with diabetic foot ulcer, Crohn’s disease and for patients with malignant and non-malignant diseases.