scholarly journals Tripartite Inhibition of SRC-WNT-PKC Signalling Consolidates Human Naïve Pluripotency

2020 ◽  
Author(s):  
Jonathan Bayerl ◽  
Muneef Ayyash ◽  
Tom Shani ◽  
Yair Manor ◽  
Ohad Gafni ◽  
...  

AbstractDifferent conditions have been devised to isolate MEK/ERK signalling independent human naïve pluripotent stem cells (PSCs) that are distinct from conventional primed PSCs and better correspond to pre-implantation developmental stages. While the naïve conditions described thus far endow human PSCs with different extents of naivety features, isolating human pluripotent cells that retain characteristics of ground state pluripotency while maintaining differentiation potential and genetic integrity, remains a major challenge. Here we engineer reporter systems that allow functional screening for conditions that can endow both the molecular and functional features expected from human naive pluripotency. We establish that simultaneous inhibition of SRC-NFκB, WNT/ßCATENIN and PKC signalling pathways is essential for enabling expansion of teratoma competent fully naïve human PSCs in defined or xeno-free conditions. Divergent signalling and transcriptional requirements for maintaining naïve pluripotency were found between mouse and human. Finally, we establish alternative naïve conditions in which MEK/ERK inhibition is substituted with inhibition for NOTCH/RBPj signalling, which allow obtaining alternative human naïve PSCs with diminished risk for loss of imprinting and deleterious global DNA hypomethylation. Our findings set a framework for the signalling foundations of human naïve pluripotency and may advance its utilization in future translational applications.Highlights of key findingsCombined inhibition of SRC, WNT and PKC signaling consolidates human naïve pluripotencyStable expansion of DNA/RNA methylation-independent and TGF/ACTIVIN-independent human naïve PSCsOpposing roles for ACTIVIN and WNT/ßCATENIN signaling on mouse vs. human naive pluripotency2i and MEK/ERKi independent alternative human naïve PSC conditions via inhibiting NOTCH/RBPj signaling

2020 ◽  
Vol 15 (4) ◽  
pp. 301-307 ◽  
Author(s):  
Gaifang Wang ◽  
Maryam Farzaneh

Primary Ovarian Insufficiency (POI) is one of the main diseases causing female infertility that occurs in about 1% of women between 30-40 years of age. There are few effective methods for the treatment of women with POI. In the past few years, stem cell-based therapy as one of the most highly investigated new therapies has emerged as a promising strategy for the treatment of POI. Human pluripotent stem cells (hPSCs) can self-renew indefinitely and differentiate into any type of cell. Human Embryonic Stem Cells (hESCs) as a type of pluripotent stem cells are the most powerful candidate for the treatment of POI. Human-induced Pluripotent Stem Cells (hiPSCs) are derived from adult somatic cells by the treatment with exogenous defined factors to create an embryonic-like pluripotent state. Both hiPSCs and hESCs can proliferate and give rise to ectodermal, mesodermal, endodermal, and germ cell lineages. After ovarian stimulation, the number of available oocytes is limited and the yield of total oocytes with high quality is low. Therefore, a robust and reproducible in-vitro culture system that supports the differentiation of human oocytes from PSCs is necessary. Very few studies have focused on the derivation of oocyte-like cells from hiPSCs and the details of hPSCs differentiation into oocytes have not been fully investigated. Therefore, in this review, we focus on the differentiation potential of hPSCs into human oocyte-like cells.


2021 ◽  
Vol 9 (Suppl 3) ◽  
pp. A114-A114
Author(s):  
Daniel Blumenthal ◽  
Linara Gabitova ◽  
Brett Menchel ◽  
Patricia Reyes-Uribe ◽  
Andrew Best ◽  
...  

BackgroundEngineered cell therapies have demonstrated significant clinical activity against hematologic malignancies, but solid tumors remain an intractable challenge. We have previously developed a human chimeric antigen receptor macrophage (CAR-M) platform for adoptive cell therapy and shown potent anti-tumor activity in pre-clinical solid tumor models.1 CAR-M overcome critical solid tumor challenges such as tumor infiltration, immunosuppression within the tumor microenvironment, lymphocyte exclusion, and target antigen heterogeneity. Currently, CAR-M are generated in a week-long ex-vivo process in which peripheral blood monocytes are differentiated into macrophages prior to genetic manipulation. Here, we demonstrate the production feasibility, phenotype, pharmacokinetics, cellular fate, specificity, and anti-tumor activity of human CD14+ CAR monocytes.MethodsUsing the chimeric adenoviral vector Ad5f35, we engineered primary human CD14+ monocytes to express a CAR targeted against human epidermal growth factor receptor 2 (HER2) (CAR-mono). Using a partially automated approach, we established a process that allowed for same day manufacturing (from Leukopak to cryopreserved CAR-mono cell product).ResultsCAR expression and cell viability exceeded 90%, and cells efficiently differentiated into CAR-expressing macrophages. The adenoviral based gene modification method led to pre-conditioning of CAR-mono cells resulting in a strong M1 phenotype upon differentiation, and potent anti-tumor activity regardless of exposure to GM-CSF, M-CSF, or immunosuppressive factors. Treating CAR-mono cells with GM-CSF and IL-4 resulted in their differentiation to monocyte-derived CAR-DCs, indicating that these cells retain their myeloid differentiation potential. In vivo, CAR-mono treatment induced anti-tumor activity in various HER2+ solid tumor xenograft models. Following intravenous administration, CAR-mono demonstrated the ability to traffic to both GM-CSF < sup >high</sup > and GM-CSF< sup >low</sup >expressing tumors. Notably, CAR-mono showed long-term CAR expression and persistence (>100 days) in both NSG and NSG-S mouse models, demonstrating lasting persistence irrespective of human cytokine support.ConclusionsThe CAR-mono platform allows for a rapid, same-day manufacturing process while maintaining the key characteristics of CAR-M therapy. Ad5f35 engineered human monocytes are primed toward M1 macrophage differentiation and produce a cell population highly similar to our established CAR-M platform. Collectively, these findings provide strong pre-clinical support to advance the CAR-mono platform into clinical testing.ReferenceKlichinsky M, et al. Human chimeric antigen receptor macrophages for cancer immunotherapy. Nature Biotechnology March 2020.


Author(s):  
Carol X.-Q. Chen ◽  
Narges Abdian ◽  
Gilles Maussion ◽  
Rhalena A. Thomas ◽  
Iveta Demirova ◽  
...  

AbstractInduced pluripotent stem cells (iPSCs) derived from human somatic cells have created new opportunities to generate disease-relevant cells. Thus, as the use of patient-derived stem cells has become more widespread, having a workflow to monitor each line is critical. This ensures iPSCs pass a suite of quality control measures, promoting reproducibility across experiments and between labs. With this in mind, we established a four-step workflow to assess our newly generated iPSCs for variations and reproducibility relative to each other and iPSCs obtained from external sources. Our benchmarks for evaluating iPSCs include examining iPSC morphology and proliferation in two different media conditions (mTeSR1 and Essential 8) and evaluating their ability to differentiate into each of the three germ layers, with a particular focus on neurons. Genomic stability in the human iPSCs was analyzed by G-band karyotyping and a qPCR-based stability test, and cell-line identity authenticated by Short Tandem Repeat (STR) analysis. Using standardized dual SMAD inhibition methods, all iPSC lines gave rise to neural progenitors that could subsequently be differentiated into cortical neurons. Neural differentiation was analyzed qualitatively by immunocytochemistry and quantitatively by q-PCR for progenitor, neuronal, cortical and glial markers. Taken together, we present a standardized quality control workflow to evaluate variability and reproducibility across and between iPSCs.HighlightsValidation of culture conditions is critical in the expansion and maintenance of an iPSC line.Characterization of pluripotency and genomic stability ensures each line is free of defects at the DNA level, while maintaining its ability to be directed into any of the three germ layers.Forebrain cortical neurons can be generated from all iPSC line tested; however, the morphology and expression pattern of these neurons can vary from line to line.


2018 ◽  
Vol 46 (sup3) ◽  
pp. S734-S739 ◽  
Author(s):  
Reyhaneh Nassiri Mansour ◽  
Fatemeh Soleimanifar ◽  
Mohamad Foad Abazari ◽  
Sepehr Torabinejad ◽  
Abdolreza Ardeshirylajimi ◽  
...  

2018 ◽  
Vol 115 (25) ◽  
pp. 6369-6374 ◽  
Author(s):  
Yonatan Y. Lipsitz ◽  
Curtis Woodford ◽  
Ting Yin ◽  
Jacob H. Hanna ◽  
Peter W. Zandstra

The development of cell-based therapies to replace missing or damaged tissues within the body or generate cells with a unique biological activity requires a reliable and accessible source of cells. Human pluripotent stem cells (hPSC) have emerged as a strong candidate cell source capable of extended propagation in vitro and differentiation to clinically relevant cell types. However, the application of hPSC in cell-based therapies requires overcoming yield limitations in large-scale hPSC manufacturing. We explored methods to convert hPSC to alternative states of pluripotency with advantageous bioprocessing properties, identifying a suspension-based small-molecule and cytokine combination that supports increased single-cell survival efficiency, faster growth rates, higher densities, and greater expansion than control hPSC cultures. ERK inhibition was found to be essential for conversion to this altered state, but once converted, ERK inhibition led to a loss of pluripotent phenotype in suspension. The resulting suspension medium formulation enabled hPSC suspension yields 5.7 ± 0.2-fold greater than conventional hPSC in 6 d, for at least five passages. Treated cells remained pluripotent, karyotypically normal, and capable of differentiating into all germ layers. Treated cells could also be integrated into directed differentiated strategies as demonstrated by the generation of pancreatic progenitors (NKX6.1+/PDX1+ cells). Enhanced suspension-yield hPSC displayed higher oxidative metabolism and altered expression of adhesion-related genes. The enhanced bioprocess properties of this alternative pluripotent state provide a strategy to overcome cell manufacturing limitations of hPSC.


2020 ◽  
Author(s):  
Seung-Hun Kim ◽  
Kwang-Hwan Choi ◽  
Mingyun Lee ◽  
Dong-Kyung Lee ◽  
Chang-Kyu Lee

Abstract l Background: The present study examined the activity and function of pig OCT4 enhancer in porcine reprogramming cells. Dual fluorescent protein reporter systems controlled by the upstream regulatory region of OCT4, which is one of the master regulators for pluripotency, are widely used in studies of the mechanism of pluripotency. We analyzed how this reporter system functions in FGF- or LIF-dependent reprogrammed porcine pluripotent stem cells using the previously established porcine-specific reporter system. l Results: Porcine embryonic fibroblasts were coinfected with the pOCT4-∆PE-eGFP (DE-GFP) and pOCT4-∆DE-DsRed2 (PE-RFP) vectors, and GFP and RFP expression was verified during a DOX-dependent reprogramming process. We demonstrated that the porcine OCT4 distal enhancer and proximal enhancer were activated in different expression patterns simultaneously as the changes in the expression of pluripotent marker genes during the establishment of porcine-induced pluripotent stem cells (iPSCs). l Conclusions: Porcine OCT4 upstream region-derived dual fluorescent protein reporter systems serve as live naïve/primed pluripotency indicators for porcine induced pluripotent cell establishment. This work demonstrates the applicability of the porcine OCT4 upstream region-derived dual fluorescence reporter system, which may be applied to investigations of species-specific pluripotency in porcine-origin cells. These reporter systems may be useful tools for studies of porcine-specific pluripotency, early embryo development and embryonic stem cells.


Author(s):  
Chiara Magliaro ◽  
Arti Ahluwalia

The aim of this study was to apply a workflow, integrating delipidation methods and advanced 3D imaging techniques for mapping of the global neuronal organization of brain organoids. These are self-organizing constructs in vitro generated from human pluripotent stem cells encased in a Matrigel shell, which resemble downscaled structural and functional features of human brains. In particular, we focused on midbrain organoids, widely considered a promising tool for studying dopaminergic neuron degeneration in Parkinson’s Disease. The evaluation of the microanatomical alterations at a patient-level will potentially guide future research of this neuropathy, providing meaningful human specific data in line with the European Directives and the 3Rs principles.


2015 ◽  
Vol 210 (7) ◽  
pp. 1257-1268 ◽  
Author(s):  
Sundari Chetty ◽  
Elise N. Engquist ◽  
Elie Mehanna ◽  
Kathy O. Lui ◽  
Alexander M. Tsankov ◽  
...  

Driving human pluripotent stem cells (hPSCs) into specific lineages is an inefficient and challenging process. We show that a potent Src inhibitor, PP1, regulates expression of genes involved in the G1 to S phase transition of the cell cycle, activates proteins in the retinoblastoma family, and subsequently increases the differentiation propensities of hPSCs into all three germ layers. We further demonstrate that genetic suppression of Src regulates the activity of the retinoblastoma protein and enhances the differentiation potential of hPSCs across all germ layers. These positive effects extend beyond the initial germ layer specification and enable efficient differentiation at subsequent stages of differentiation.


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