Mesenchymal stem/stromal cells (MSC) are promising candidates for use in cell-based therapies. (typically 500-750 g 4), which can be harvested aseptically during cesarean section with no risk to the donor. MSC derived from placenta have long-term proliferation 5 and immunomodulatory capacity 6, superior to bone marrow-derived MSC. In a previous study, we demonstrated that a single term placenta contained sufficient MSC for the manufacture of up to 7,000 clinical doses 4. These characteristics make placenta an ideal source tissue for the manufacture of allogeneic MSC. The placenta is usually a fetomaternal organ consisting of both fetal and maternal tissue 7, and thus MSC of fetal or maternal origin can be, theoretically, isolated. The following references provide detailed information around TH-302 manufacturer the development and pathology, as well as microscopic and macroscopic examination of the human placenta and adnexa 8,9. The placenta proper is usually comprised largely of fetal blood vessels and secretory TH-302 manufacturer and supporting cells called trophoblasts, making up the chorionic villi covered by the chorion frondosum (plate) 8. The branched placental villi are bathed in maternal blood delivered from the uterine spiral arteries, enabling nutrient, hormone and gas exchange between BGLAP fetus and mother. The placenta is usually anchored to the endometrium via maternal decidual stromal cells and fetal extravillious trophoblasts are interspersed in extracellular matrix 8. The villi converge onto the fetal chorionic plate where they?form the umbilical TH-302 manufacturer cord 8. An outcome of the first International Workshop on Placental-Derived Stem Cells (2008) was an appreciation of the need to standardize the isolation and characterization of cells from human term placenta 10. Because of the anatomy of the placenta, dissection of the different tissues, isolation of MSC and anticipated culture outcomes can be overwhelming for newcomers to the field. In this protocol, the harvest of placental chorionic tissues, followed by MSC isolation and expansion is usually thoroughly detailed. MSC characterization via flow cytometry and differentiation are considered routine 5,11-13, and thus only briefly detailed here. As highlighted in a recent systematic literature review 14, MSC obtained from the placental chorionic villi are generally assumed to be fetal. Although, only 18% of studies examined the origin of the MSC obtained, and of those, only half of TH-302 manufacturer the studies reported fetal MSC and the other half reported maternal or mixed MSC populations. Each of the three tissue components described herein (chorionic villi, chorionic plate and decidua basalis) are composed primarily of the fetal membrane/villi, and a small proportion of uterine-derived maternal cells, which remain attached to the delivered placenta. We provide data demonstrating that isolating MSC from the maternal side of the placenta, rather than the fetal side of the placenta, as we have previously reported 5,11, is usually a more appropriate starting material if maternal MSC are desired. This protocol also describes the use of XY FISH to validate fetal or maternal contribution to cell cultures. While this is a standard protocol from the manufacturer, this analysis is usually often neglected and its importance underestimated 14. Protocol The Human Research Ethics Committees at Mater Health Services, Royal Brisbane and Women’s Hospital, Queensland University of Technology and the University of Queensland approved the research and collection of human placenta samples used in the study. All protocols complied with national research guidelines. Patients provided informed written consent for the use of tissue for research purposes. Third trimester placentas were obtained from healthful mothers following regular Caesarean section (CS) births at term through the above-mentioned private hospitals in Brisbane, Australia. Man discordant pregnancies for term examples were employed in this scholarly research to tell apart fetal from maternal cells. Fetal gender have been determined.