A Cerebral Organoid Connectivity Apparatus to Model Neuronal Tract Circuitry

Mental disorders have high prevalence, but the efficacy of existing therapeutics is limited, in part, because the pathogenic mechanisms remain enigmatic. Current models of neural circuitry include animal models and post-mortem brain tissue, which have allowed enormous progress in understanding the pathophysiology of mental disorders. However, these models limit the ability to assess the functional alterations in short-range and long-range network connectivity between brain regions that are implicated in many mental disorders, e.g., schizophrenia and autism spectrum disorders. This work addresses these limitations by developing an in vitro model of the human brain that models the in vivo cerebral tract environment. In this study, microfabrication and stem cell differentiation techniques were combined to develop an in vitro cerebral tract model that anchors human induced pluripotent stem cell-derived cerebral organoids (COs) and provides a scaffold to promote the formation of a functional connecting neuronal tract. Two designs of a Cerebral Organoid Connectivity Apparatus (COCA) were fabricated using SU-8 photoresist. The first design contains a series of spikes which anchor the CO to the COCA (spiked design), whereas the second design contains flat supporting structures with open holes in a grid pattern to anchor the organoids (grid design); both designs allow effective media exchange. Morphological and functional analyses reveal the expression of key neuronal markers as well as functional activity and signal propagation along cerebral tracts connecting CO pairs. The reported in vitro models enable the investigation of critical neural circuitry involved in neurodevelopmental processes and has the potential to help devise personalized and targeted therapeutic strategies.

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Non-Ionizing Radiation for Cardiac Human Amniotic Mesenchymal Stromal Cell Commitment: A Physical Strategy in Regenerative Medicine

International Journal of Molecular Sciences ◽

10.3390/ijms19082324 ◽

2018 ◽

Vol 19 (8) ◽

pp. 2324 ◽

Cited By ~ 1

Author(s):

Mario Ledda ◽

Enrico D’Emilia ◽

Maria Lolli ◽

Rodolfo Marchese ◽

Claudio De Lazzari ◽

...

Keyword(s):

Stem Cell ◽

Cell Therapy ◽

Adult Stem Cells ◽

Myocardial Damage ◽

Stem Cell Differentiation ◽

Differentiation Markers ◽

Innovative Strategy ◽

Cell Commitment

Cell therapy is an innovative strategy for tissue repair, since adult stem cells could have limited regenerative ability as in the case of myocardial damage. This leads to a local contractile dysfunction due to scar formation. For these reasons, refining strategy approaches for “in vitro” stem cell commitment, preparatory to the “in vivo” stem cell differentiation, is imperative. In this work, we isolated and characterized at molecular and cellular level, human Amniotic Mesenchymal Stromal Cells (hAMSCs) and exposed them to a physical Extremely Low Frequency Electromagnetic Field (ELF-EMF) stimulus and to a chemical Nitric Oxide treatment. Physically exposed cells showed a decrease of cell proliferation and no change in metabolic activity, cell vitality and apoptotic rate. An increase in the mRNA expression of cardiac and angiogenic differentiation markers, confirmed at the translational level, was also highlighted in exposed cells. Our data, for the first time, provide evidence that physical ELF-EMF stimulus (7 Hz, 2.5 µT), similarly to the chemical treatment, is able to trigger hAMSC cardiac commitment. More importantly, we also observed that only the physical stimulus is able to induce both types of commitments contemporarily (cardiac and angiogenic), suggesting its potential use to obtain a better regenerative response in cell-therapy protocols.

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Human adipose stem cell differentiation is highly affected by cancer cells both in vitro and in vivo: implication for autologous fat grafting

Cell Death and Disease ◽

10.1038/cddis.2016.308 ◽

2017 ◽

Vol 8 (1) ◽

pp. e2568-e2568 ◽

Cited By ~ 31

Author(s):

Francesca Paino ◽

Marcella La Noce ◽

Diego Di Nucci ◽

Giovanni Francesco Nicoletti ◽

Rosa Salzillo ◽

...

Keyword(s):

Stem Cell ◽

Cell Differentiation ◽

Stem Cell Differentiation ◽

Fat Grafting ◽

Adipose Stem Cell ◽

Autologous Fat Grafting ◽

Autologous Fat ◽

Human Adipose Stem Cell

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MHC class II cell-autonomously regulates self-renewal and differentiation of normal and malignant B cells

Blood ◽

10.1182/blood-2018-11-885467 ◽

2019 ◽

Vol 133 (10) ◽

pp. 1108-1118 ◽

Cited By ~ 3

Author(s):

Julia Merkenschlager ◽

Urszula Eksmond ◽

Luca Danelli ◽

Jan Attig ◽

George R. Young ◽

...

Keyword(s):

Stem Cell ◽

B Cells ◽

B Cell ◽

Stem Cell Differentiation ◽

Class Ii ◽

Cell Phenotype ◽

Self Renewal ◽

Mhc Ii

Abstract Best known for presenting antigenic peptides to CD4+ T cells, major histocompatibility complex class II (MHC II) also transmits or may modify intracellular signals. Here, we show that MHC II cell-autonomously regulates the balance between self-renewal and differentiation in B-cell precursors, as well as in malignant B cells. Initiation of MHC II expression early during bone marrow B-cell development limited the occupancy of cycling compartments by promoting differentiation, thus regulating the numerical output of B cells. MHC II deficiency preserved stem cell characteristics in developing pro-B cells in vivo, and ectopic MHC II expression accelerated hematopoietic stem cell differentiation in vitro. Moreover, MHC II expression restrained growth of murine B-cell leukemia cell lines in vitro and in vivo, independently of CD4+ T-cell surveillance. Our results highlight an important cell-intrinsic contribution of MHC II expression to establishing the differentiated B-cell phenotype.

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Abstract 78: Pnmt+ "Primer" Cells Give Rise to Cardiac Myocytes and Neurons in the Mammalian Heart: Development of New Experimental Tools for Cardiac Regenerative Medicine Applications

Circulation Research ◽

10.1161/res.111.suppl_1.a78 ◽

2012 ◽

Vol 111 (suppl_1) ◽

Author(s):

Namita M Varudkar ◽

Jixiang Xia ◽

Ibrahim Abukenda ◽

Karl Pfeifer ◽

Steven Ebert

Keyword(s):

Stem Cell ◽

Regenerative Medicine ◽

Neural Crest ◽

Heart Development ◽

Embryonic Stem ◽

Mouse Embryonic Stem Cell ◽

Stem Cell Differentiation ◽

Left Ventricular

Phenylethanolamine n-methyltransferase (Pnmt) catalyzes the conversion of norepinephrine to epinephrine, and thus serves as a marker for adrenergic cells. We employed a combination of immunofluorescent histochemical staining and genetic fate-mapping strategies to show that two separate Pnmt+ cell populations contribute to heart development. Intrinsic cardiac adrenergic (ICA) cells originate from the primary heart field, and contribute to pacemaking, conduction, and working (contractile) myocardium. A second population of cardiac Pnmt+ cells is derived from migrating neural crest. These neural crest adrenergic (NCA) cells appear to contribute to cardiac neurons. By adulthood, most of the Pnmt+ cells show a distinctively left-sided orientation in the heart, with nearly 90% of them being found in the left atrium and ventricle. Surprisingly large swaths of ventricular muscle are derived from Pnmt+ primer cells. Since this region of the heart is highly vulnerable to coronary artery disease and often sustains varying degrees of damage following myocardial infarction, we hypothesize that directed stem cell differentiation into Pnmt+ primer cells could serve as a valuable resource for repair and/or regeneration of left ventricular myocardium for heart disease patients. To test this hypothesis, we have generated stable recombinant mouse embryonic stem cell (mESC) lines that express various fluorescent marker proteins under the control of the endogenous Pnmt gene regulatory network. These cells can be rapidly expanded in culture, sorted, and used for transplantation studies in animal models to determine their therapeutic effectiveness. The cells can be induced along cardiogenic or neurogenic pathways in vitro, and the resulting Pnmt+ cells from each population can then be collected and tested in vivo. To achieve this goal, we have knocked-in a nuclear-localized enhanced green fluorescent protein into the Pnmt locus to create Pnmt-nEGFP recombinant mESCs and mice. We show that nEGFP expression is specifically expressed in Pnmt+ cells in vitro and in vivo. This strategy allows us to identify and isolate Pnmt+ cells to evaluate their effectiveness for cardiac regenerative medicine applications. .

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A Fast Optical Method to Direct High Linage-Commitment Stem-Cell Differentiation by a Short Flash of Ultrafast Laser Activation In vitro and In vivo

SSRN Electronic Journal ◽

10.2139/ssrn.3758208 ◽

2020 ◽

Author(s):

Wanyi Tang ◽

Haipeng Wang ◽

Shiyue Liu ◽

Siu Kai Kong ◽

Aaron Ho ◽

...

Keyword(s):

Stem Cell ◽

Cell Differentiation ◽

Optical Method ◽

Stem Cell Differentiation ◽

Ultrafast Laser

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MT1-MMP Plays a Critical Role in Hematopoiesis by Regulating HIF-Mediated Chemo-/Cytokine Gene Transcription within Niche Cells.

Blood ◽

10.1182/blood.v120.21.2351.2351 ◽

2012 ◽

Vol 120 (21) ◽

pp. 2351-2351

Author(s):

Chiemi Nishida ◽

Kaori Sato-Kusubata ◽

Yoshihiko Tashiro ◽

Ismael Gritli ◽

Aki Sato ◽

...

Keyword(s):

Stem Cells ◽

Stem Cell ◽

Gene Transcription ◽

Stromal Cells ◽

Stromal Cell ◽

Stem Cell Differentiation ◽

Cell Phenotype ◽

Hematopoietic Stem

Abstract Abstract 2351 Stem cells reside in a physical niche. The organization of cellular niches has been shown to play a key role in regulating normal stem cell differentiation, stem cell maintenance and regeneration. Various stem cell niches have been shown to be hypoxic, thereby maintaining the stem cell phenotype of e.g. hematopoietic stem cells (HSCs) or cancer stem cells. The bone marrow (BM) niche is a rich reservoir of tissue-specific pluripotent HSCs. Proteases such as matrix metalloproteinases (MMPs) have been implicated in cell movement, partly due to their proteolytic function, and they have been linked to cellular processes such as cell proliferation and differentiation. The proteolytic function of Membrane-type 1 MMP (MT1-MMP/MMP-14) is essential for angiogenesis, arthritis and tumour growth. Recently, it has been reported that MT1-MMP is highly expressed in HSCs and stromal/niche cells. However the clear function of MT1-MMP in hematopoiesis is not well understood. To reveal the functional consequences of MT1-MMP deficiency for post-natal hematopoiesis in vivo, we have taken advantage of MT1-MMP−/− mice to demonstrate that MT1-MMP deficiency leads to impaired steady state hematopoiesis of all hematopoietic cell lineages. In a search for factors whose deficiency could cause this hematopoietic phenotype, we found not only reduced protein release, but also reduced transcription of the following growth factors/chemokines in MT1-MMP−/− mice: erythropoietin (Epo), stromal cell-derived factor-1 (SDF-1a/CXCL12), interleukin-7 (IL-7) and Kit ligand (KitL, also known as stem cell factor). All of these factors, except for Epo, are typical stromal cell-derived factors. To ensure that impaired gene transcription in vivo was not due to a lower number of stromal cells in vivo, we demonstrated that MT1-MMP knockdown in stromal cells in vitro also reduced transcription of the stromal cell derived factors SDF-1a/CXCL12, IL-7 and KitL. In contrast, overexpression of MT1-MMP in stromal cells enhanced gene transcription of these factors. All genes, whose transcription was altered in vitro and in vivo due to MT1-MMP deficiency, had one thing in common: their gene transcription is regulated by the hypoxia inducible factor-1 (HIF-1) pathway. Further mechanistic studies revealed that MT1-MMP activates the HIF-1 pathway via factor inhibiting HIF-1 (FIH-1) within niche cells, thereby inducing the transcription of HIF-responsive genes, which induce terminal hematopoietic differentiation. Thus, MT1-MMP in niche cells regulates postnatal hematopoiesis by modulating hematopoietic HIF-dependent niche factors that are critical for terminal differentiation and migration. Disclosures: No relevant conflicts of interest to declare.

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Functions of Circular RNAs in Regulating Adipogenesis of Mesenchymal Stem Cells

Stem Cells International ◽

10.1155/2020/3763069 ◽

2020 ◽

Vol 2020 ◽

pp. 1-12

Author(s):

Fanglin Wang ◽

Xiang Li ◽

Zhiyuan Li ◽

Shoushuai Wang ◽

Jun Fan

Keyword(s):

Stem Cells ◽

Mesenchymal Stem Cells ◽

Stem Cell ◽

Cell Differentiation ◽

Stem Cell Differentiation ◽

Circular Rna ◽

Circular Rnas ◽

Differentiation Process

The mesenchymal stem cells (MSCs) are known as highly plastic stem cells and can differentiate into specialized tissues such as adipose tissue, osseous tissue, muscle tissue, and nervous tissue. The differentiation of mesenchymal stem cells is very important in regenerative medicine. Their differentiation process is regulated by signaling pathways of epigenetic, transcriptional, and posttranscriptional levels. Circular RNA (circRNA), a class of noncoding RNAs generated from protein-coding genes, plays a pivotal regulatory role in many biological processes. Accumulated studies have demonstrated that several circRNAs participate in the cell differentiation process of mesenchymal stem cells in vitro and in vivo. In the current review, characteristics and functions of circRNAs in stem cell differentiation will be discussed. The mechanism and key role of circRNAs in regulating mesenchymal stem cell differentiation, especially adipogenesis, will be reviewed and discussed. Understanding the roles of these circRNAs will present us with a more comprehensive signal path network of modulating stem cell differentiation and help us discover potential biomarkers and therapeutic targets in clinic.

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Blockage of neddylation modification stimulates tumor sphere formation in vitro and stem cell differentiation and wound healing in vivo

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1522367113 ◽

2016 ◽

Vol 113 (21) ◽

pp. E2935-E2944 ◽

Cited By ~ 23

Author(s):

Xiaochen Zhou ◽

Mingjia Tan ◽

Mukesh K. Nyati ◽

Yongchao Zhao ◽

Gongxian Wang ◽

...

Keyword(s):

Wound Healing ◽

Stem Cell ◽

Human Cancer ◽

Embryonic Stem ◽

Stem Cell Differentiation ◽

Skin Wound Healing ◽

Tumor Sphere ◽

Sphere Formation

MLN4924, also known as pevonedistat, is the first-in-class inhibitor of NEDD8-activating enzyme, which blocks the entire neddylation modification of proteins. Previous preclinical studies and current clinical trials have been exclusively focused on its anticancer property. Unexpectedly, we show here, to our knowledge for the first time, that MLN4924, when applied at nanomolar concentrations, significantly stimulates in vitro tumor sphere formation and in vivo tumorigenesis and differentiation of human cancer cells and mouse embryonic stem cells. These stimulatory effects are attributable to (i) c-MYC accumulation via blocking its degradation and (ii) continued activation of EGFR (epidermal growth factor receptor) and its downstream pathways, including PI3K/AKT/mammalian target of rapamycin and RAS/RAF/MEK/ERK, via inducing EGFR dimerization. Finally, MLN4924 accelerates EGF-mediated skin wound healing in mouse and stimulates cell migration in an in vitro culture setting. Taking these data together, our study reveals that neddylation modification could regulate stem cell proliferation and differentiation and that a low dose of MLN4924 might have a therapeutic value for stem cell therapy and tissue regeneration.

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Stem cell factor enhances the survival but not the self-renewal of murine hematopoietic long-term repopulating cells

Blood ◽

10.1182/blood.v84.2.408.bloodjournal842408 ◽

1994 ◽

Vol 84 (2) ◽

pp. 408-414 ◽

Cited By ~ 6

Author(s):

CL Li ◽

GR Johnson

Keyword(s):

Stem Cell ◽

Stem Cell Factor ◽

Cultured Cells ◽

Stem Cell Differentiation ◽

The Self ◽

Isolated Cells ◽

Self Renewal

The effects of stem cell factor (SCF) have been tested on a murine bone marrow subpopulation (RH123lo, Lin-, Ly6A/E+) that is highly enriched for long-term hematopoietic repopulating cells. SCF maintained cells from this population with long-term repopulating ability for up to 10 days in vitro. However, compared with freshly isolated cells, the level of engraftment in vivo by the cultured cells declined during the in vitro culture period, suggesting that SCF alone was unable to stimulate the self-renewal of long-term repopulating cells. By direct visualization of cultures, only small numbers of cells survived and rarely underwent cell division. However, SCF did directly stimulate proliferation of a population (Rh123med/hi,Lin-,Ly6A/E+) enriched for short-term repopulating cells. These data suggest that stem cell differentiation is associated with the development of mitogenic activity by SCF at least in some progenitor cell populations.

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