GSE125592
A Patient specific iPSC-based model of Hydatidiform mole reveals abnormal BMP4 signaling caused by NLRP7 deficiency
Complete Hydatidiform Mole (HM) is a gestational trophoblastic disease resulting in hyper proliferation of trophoblast cells and absence of embryo development. Mutations in NLRP7 gene is a  major cause of familial recurrent complete HM, where no embryonic tissue is present during the pregnancy. NLRP7 is a novel protein and its function is poorly understood. Lack of NLRP7 in the mouse genome and challenges in studying  human embryogenesis as well as human trophoblast differentiation has prevented elucidation of the pathophysiology of this disease and the function of NLRP7 in HM. Here, we established an in vitro model of HM using NLRP7 deficient patient-derived human induced pluripotent stem cells (iPSCs). Whole transcriptome profiling during trophoblast differentiation revealed that NLRP7 deficiency results in precocious downregulation of pluripotency factors, activation of trophoblast genes and promotes maturation of differentiated extraembryonic cell types such as syncytiotrophoblasts. We further showed that these phenotypes are dependent on BMP4 signaling and BMP pathway inhibition prevented excessive trophoblast differentiation of HM-iPSCs. Taken together, this novel human iPSC model of a genetic placental disease recapitulates aspect of trophoblast biology and sheds light on early human embryogenesis by identifying NLRP7 as an important regulator of this process. Overall design: mRNA profiles were obtained from trophoblast-like cells derived from patient specific iPSCs and unrelated healty control iPSCs upon treatment via FGF and ACTIVIN/NODAL inhibitors together with either BMP4 or BMP inhibitor.