Project description:Human pluripotent cells were reset to ground state pluripotency by transient overexpression of NANOG and KLF2 and subsequent inhibition of ERK and protein kinase C. Transcriptional profiling of reset cells and conventional pluripotent stem cell cultures was carried out by RNA-seq, in tandem with mouse embryonic stem cells propagated under similar conditions to assess the combinatorial effects of MEK inhibitor PD0325901, GSK3 inhibitor CHIR99021 and PKC inhibitor Go6983.
Project description:Human pluripotent cells were reset to ground state pluripotency by transient overexpression of NANOG and KLF2 and subsequent inhibition of ERK and protein kinase C. Transcriptional profiling of H9 parental and clonal lines, and induced pluripotent stem cells derived from adult fibroblast and adipose cell types was carried out in reset and conventional culture conditions.
Project description:In human embryos, naive pluripotent cells of the inner cell mass (ICM) generate epiblast, primitive endoderm and trophectoderm (TE) lineage, whence trophoblast cells derive. In vitro, naive pluripotent stem cells (PSCs) retain this potential and efficiently generate trophoblast stem cells (TSCs), while conventional PSCs form TSCs at low efficiency. Transient histone deacetylase and MEK inhibitions with LIF stimulation is used to chemically reset conventional to naive PSCs. Here we report that chemical resetting induces expression of both naive and TSC markers and of placental imprinted genes. A modified chemical resetting protocol allows for the fast and efficient conversion of conventional PSCs into TSCs, entailing shutdown of pluripotency genes and full activation of the trophoblast master regulators, without induction of amnion markers. Chemical resetting generates a plastic intermediate state, characterised by co-expression of naive and TSC markers, after which cells steer towards one of the two fates in response to the signalling environment. The efficiency and rapidity of our system will be useful to study cell fate transitions, and to generate models of placental disorders.
Project description:A simple method is presented to reset human pluripotent cells to a naive state via transient histone deacetylase inhibition and maintenance in chemically-defined naive stem cell culture media. Cells can be reset without transgenes and expanded continuously either on feeders or alternative substrates in feeder-free conditions. Multiple cell lines of varying origin were reset and characterised in parallel with conventionally cultured counterparts.
Project description:Generation of T cells from pluripotent stem cells (PSC) has the potential to transform adoptive immunotherapy for cancer into universal donor, off-the-shelf cellular therapies. However, differentiation of human PSCs into fully mature T cells has been challenging with existing methods. We report that a 3D organoid method permitted efficient differentiation of human embryonic stem cell and induced pluripotent stem cell-derived mesoderm progenitors to mature, functional conventional T cells with a diverse T cell receptor (TCR) repertoire. This continuous culture system supported both hematopoietic induction and terminal differentiation to naïve, conventional CD3+CD8αβ+ and CD3+CD4+ T cells. Introduction of a Class I-restricted TCR in PSCs produced antigen-specific CD8αβ+ T cells lacking endogenous TCR expression. Functional assays and RNA sequencing aligned PSC-derived T cells with primary naïve conventional CD8+ T cells. The organoid system presented here provides an effective and scalable platform to generate functional mature T cells from human PSCs.
Project description:Current human pluripotent stem cells lack the transcription factor circuitry that governs the ground state of mouse embryonic stem cells (ESC). Here we report that short-term expression of two components, NANOG and KLF2, is sufficient to ignite other elements of the network and reset the human pluripotent state. Inhibition of ERK and protein kinase C signalling sustains a transgene-independent rewired state. Reset cells self-renew continuously without ERK signalling, are phenotypically stable and karyotypically intact. They differentiate in vitro and form teratomas in vivo. Metabolism is reprogrammed in reset cells with activation of mitochondrial respiration as in ESC. DNA methylation is dramatically reduced and transcriptome state is globally realigned across multiple cell lines. Depletion of ground state transcription factors, TFCP2L1 or KLF4 has marginal impact on conventional human pluripotent stem cells, but collapses the reset state. These findings demonstrate feasibility of installing and propagating functional control circuitry for ground state pluripotency in human cells. DNA methylation analysis in Conventional and Reset human embryonic stem cells by whole genome bisulfite sequencing, in triplicate, using the Illumina platform
Project description:Metabolism is vital to cellular function and tissue homeostasis during human lung development. In utero, embryonic pluripotent stem cells undergo endodermal differentiation towards a lung progenitor cell fate that can be mimicked in vitro using induced human pluripotent stem cells (hiPSCs) to study genetic mutations. To identify differences between wild type and surfactant protein B (SFTPB)-deficient cell lines during endoderm specification towards lung, we used an untargeted metabolomics approach to evaluate the developmental changes in metabolites. We found that the metabolites most enriched during the differentiation from pluripotent stem cell to lung progenitor cell, regardless of cell line, were sphingomyelins and phosphatidylcholines, two important lipid classes in fetal lung development. The SFTPB mutation had no metabolic impact on early endodermal lung development. The identified metabolite signatures during lung progenitor cell differentiation may be utilized as biomarkers for normal embryonic lung development.