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Mutations in STAMBP have been well-established to cause congenital human microcephaly-capillary malformation (MIC-CAP) syndrome, a rare genetic disorder characterized by global developmental delay, severe microcephaly, capillary malformations, etc. Previous biochemical investigations and loss-of-function studies in mice have provided insights into the mechanism of STAMBP, however, it remains controversial how STAMBP deficiency leads to malformation of those affected tissues in patients. In this study, we investigated the function and underlying mechanism of STAMBP during neural differentiation of human embryonic stem cells (hESCs). We found that STAMBP is dispensable for the pluripotency maintenance or neural differentiation of hESCs. However, neural progenitor cells (NPCs) derived from STAMBP-deficient hESCs fail to be long-term maintained/expanded in vitro. We identified the anti-apoptotic protein CFLAR is down-regulated in those affected NPCs and ectopic expression of CFLAR rescues NPC defects induced by STAMBP-deficiency. Our study not only provides novel insight into the mechanism of neural defects in STAMBP mutant patients, it also indicates that the death receptor mediated apoptosis is an obstacle for long-term maintenance/expansion of NPCs in vitro thus counteracting this cell death pathway could be beneficial to the generation of NPCs in vitro., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

TGF-β signaling family plays an essential role to regulate fate decisions in pluripotency and lineage specification. How the action of TGF-β family signaling is intrinsically executed remains not fully elucidated. Here, we show that HBO1, a MYST histone acetyltransferase (HAT) is an essential cell intrinsic determinant for TGF-β signaling in human embryonic stem cells (hESCs). HBO1-/- hESCs fail to response to TGF-β signaling to maintain pluripotency and spontaneously differentiate into neuroectoderm. Moreover, HBO1 deficient hESCs show complete defect in mesendoderm specification in BMP4-triggered gastruloids or teratomas. Molecularly, HBO1 interacts with SMAD4 and co-binds the open chromatin labeled by H3K14ac and H3K4me3 in undifferentiated hESCs. Upon differentiation, HBO1/SMAD4 co-bind and maintain the mesoderm genes in BMP4-triggered mesoderm cells while lose chromatin occupancy in neural cells induced by dual-SMAD inhibition. Our data reveal an essential role of HBO1, a chromatin factor to determine the action of SMAD in both human pluripotency and mesendoderm specification., (© The Author(s) 2024. Published by Oxford University Press on behalf of Nucleic Acids Research.)

A stable, rapid and effective neural differentiation method is essential for the clinical applications of human embryonic stem cells (ESCs) or induced pluripotent stem cells (iPSCs) in treating neurological disorders and diseases. Herein, we established a novel and robust monolayer differentiation method to produce functional neural progenitor cells (NPCs) from human ESC/iPSCs on Type I Collagen. The derived cells not only displayed the requisite markers, but also behaved similarly to classic NPCs both in vitro and in vivo. Upon transplantation into traumatic brain injury model, the derived NPCs facilitated recovery from injury. We also found that SMAD signaling stayed down throughout the differentiation process on Type I Collagen, and the pluripotent signals were rapidly downregulated along with raising up of neural early markers on the third day. Meanwhile, ATAC-seq data showed the related mediation of distinct transcriptome and global chromatin dynamics during NPC induction. Totally, our results thus provide a convenient way to generate NPCs from human ESC/iPSCs for neural diseases' treatment., (© 2021. Science China Press and Springer-Verlag GmbH Germany, part of Springer Nature.)

Neurogenesis, a highly orchestrated process, entails the transition from a pluripotent to neural state and involves neural progenitor cells (NPCs) and neuronal/glial subtypes. However, the precise epigenetic mechanisms underlying fate decision remain poorly understood. Here, we delete KDM6s (JMJD3 and/or UTX), the H3K27me3 demethylases, in human embryonic stem cells (hESCs) and show that their deletion does not impede NPC generation from hESCs. However, KDM6-deficient NPCs exhibit poor proliferation and a failure to differentiate into neurons and glia. Mechanistically, both JMJD3 and UTX are found to be enriched in gene loci essential for neural development in hNPCs, and KDM6 impairment leads to H3K27me3 accumulation and blockade of DNA accessibility at these genes. Interestingly, forced expression of neuron-specific chromatin remodelling BAF (nBAF) rescues the neuron/glia defect in KDM6-deficient NPCs despite H3K27me3 accumulation. Our findings uncover the differential requirement of KDM6s in specifying NPCs and neurons/glia and highlight the contribution of individual epigenetic regulators in fate decisions in a human development model.

Human induced pluripotent stem cells (hiPSCs) may provide potential resource for regenerative medicine research, including generation of insulin-producing cells for diabetes research and insulin production. Testosterone (T) is an androgen hormone which promotes protein synthesis and improves the management of type 2 diabetes in clinical studies. Concurrently, co-existed hyperandrogenism and hyperinsulinism is frequently observed in polycystic ovary syndrome, congenital adrenal hyperplasia and some of Wermer's syndrome. However, the relationship among androgens, insulin and the differentiation of pancreatic β cells is still not fully clear. Here we find that T improves the differentiation efficiency of insulin-producing cells from hiPSCs. The addition of T into routine differentiation formula for pancreatic β cells increases the differentiation efficiency from 12% to 35%. The administration of T promotes the expression of key genes associated with β cells differentiation including NGN3, NEUROD1 and INS. This finding benefits the ongoing process to optimize the differentiation protocol of pancreatic β cells from hiPSCs, and provides some degree of understanding the clinical management of T for type 2 diabetes.

Generation of induced pluripotent stem cells (iPSCs) from human urine-derived cells (hUCs) provides a convenient and non-invasive way to obtain patient-specific iPSCs. However, many isolated hUCs exhibit very poor proliferation and are difficult to reprogram. In this study, we optimized reprogramming approaches for hUCs with very poor proliferation. We report here that a compound cocktail containing cyclic pifithrin-a (a P53 inhibitor), A-83-01, CHIR99021, thiazovivin, NaB, and PD0325901 significantly improves the reprogramming efficiency (170-fold more) for hUCs. In addition, we showed that replacement of Matrigel with autologous hUC feeders can overcome the reprogramming failure due to the massive cell death that occurs during delivery of reprogramming factors. In summary, we describe improved approaches to enable iPSC generation from hUCs that were otherwise difficult to reprogram, a valuable asset for banking patient-specific iPSCs., (Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.)