Human amniotic epithelial cells: proliferation and apoptosis during their hepatic differentiation

JULIETA L. MAYMÓ; ANTONIO PÉREZ PÉREZ; RODRIGO RIEDEL; BERNARDO MASKIN; MARIANA JAIME; ORNELLA PAROLINI; VÍCTOR SÁNCHEZ MARGALET; CECILIA L. VARONE

Simposio; VI SLIMP- Latin American Symposium on Maternal Fetal Interaction & Placenta; 2015

Objective: The placenta and fetal membranes have recently been proposed as an important stem cells source for regenerative medicine. Gestational cells offer considerable advantages over other stem cells such as bone marrow or embryo-derived cells. There is a virtually unlimited potential supply of, an easy access, and minimal ethical and legal barriers are associated with the collection and use of such tissues. Epithelial amniotic cells (hAECs) can be isolated from the amnion of the human placenta at term. They express embryonic stem cells markers and have the ability to differentiate toward all three germ layers. HAECs are non tumorigenic and have immunosuppressive properties. These characteristics would make hAECs ideal candidates for tissue engineering and application in regenerative medicine. Hepatic failure is one of the major causes of morbidity and mortality worldwide. Recently, stem cells have been spotlighted as alternative sources of hepatocytes because their specific potential for differentiation. The aim of this work was to study the proliferation and apoptosis of hAECs, during early and late hepatic differentiation. We have also analyzed hepatic markers expression through this process. Methods and results: Hepatic differentiation was assayed by specific factors (EGF + dexamethasone) or by HepG2 conditioned medium (CM). We have found a significant increment of caspase-3 fragmentation, after 72 h of CM treatment, measured by western blot. We observed an augmentation in p53 and p21 genes expression and a decline in cyclin D1, measured by qRT-PCR. The opposite effects were observed with the specific factors treatment. We have also determined by 3H-thymidine incorporation, that EGF significant increased cell proliferation while CM diminished it. During hAECs differentiation we observed a significant increment in hepatocytes-related genes expression (α-fetoprotein, α1-AT, albumin, CYP7A1) and in albumin expression, measured by qRT-PCR and Western blot, respectively. Conclusions. Our results begin to unravel molecular and cellular process that take place during hepatic differentiation of hAECs