Collagen nanofibril self-assembly on a natural polymeric material for the osteoinduction of stem cells in vitro and biocompatibility in vivo

RSC Advances ◽  
2016 ◽  
Vol 6 (84) ◽  
pp. 80851-80866 ◽  
Author(s):  
A. Aravamudhan ◽  
D. M. Ramos ◽  
N. A. Jenkins ◽  
N. A. Dyment ◽  
M. M. Sanders ◽  
...  
Keyword(s):  
Stem Cells ◽  
Stem Cell ◽  
Self Assembly ◽  
Stem Cell Differentiation ◽  
Host Tissue ◽  
Tissue Response ◽  
Microporous Structure

This manuscript reports the characterization of molecularly self-assembled collagen nanofibers on a natural polymeric microporous structure and their ability to support stem cell differentiation in vitro and host tissue response in vivo.

Isolation and characterization of human CD34−Lin− and CD34+Lin− hematopoietic stem cells using cell surface markers AC133 and CD7

Blood ◽  
2000 ◽  
Vol 95 (9) ◽  
pp. 2813-2820 ◽  
Author(s):  
Lisa Gallacher ◽  
Barbara Murdoch ◽  
Dongmei M. Wu ◽  
Francis N. Karanu ◽  
Mike Keeney ◽  
...  
Keyword(s):  
Stem Cells ◽  
Stem Cell ◽  
Surface Markers ◽  
Cell Surface Markers ◽  
Hematopoietic Stem ◽  
Human Cd34 ◽  
Cd34 Cells

Recent evidence indicates that human hematopoietic stem cell properties can be found among cells lacking CD34 and lineage commitment markers (CD34−Lin−). A major barrier in the further characterization of human CD34− stem cells is the inability to detect this population using in vitro assays because these cells only demonstrate hematopoietic activity in vivo. Using cell surface markers AC133 and CD7, subfractions were isolated within CD34−CD38−Lin− and CD34+CD38−Lin− cells derived from human cord blood. Although the majority of CD34−CD38−Lin− cells lack AC133 and express CD7, an extremely rare population of AC133+CD7− cells was identified at a frequency of 0.2%. Surprisingly, these AC133+CD7− cells were highly enriched for progenitor activity at a frequency equivalent to purified fractions of CD34+ stem cells, and they were the only subset among the CD34−CD38−Lin− population capable of giving rise to CD34+ cells in defined liquid cultures. Human cells were detected in the bone marrow of non-obese/severe combined immunodeficiency (NOD/SCID) mice 8 weeks after transplantation of ex vivo–cultured AC133+CD7− cells isolated from the CD34−CD38−Lin− population, whereas 400-fold greater numbers of the AC133−CD7− subset had no engraftment ability. These studies provide novel insights into the hierarchical relationship of the human stem cell compartment by identifying a rare population of primitive human CD34− cells that are detectable after transplantation in vivo, enriched for in vitro clonogenic capacity, and capable of differentiation into CD34+ cells.

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

Blood ◽  
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.

scholarly journals Functions of Circular RNAs in Regulating Adipogenesis of Mesenchymal Stem Cells

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.

Nanocarrier Mediated siRNA Delivery Targeting Stem Cell Differentiation

2020 ◽  
Vol 15 (2) ◽  
pp. 155-172 ◽  
Author(s):  
Fiona Fernandes ◽  
Pooja Kotharkar ◽  
Adrija Chakravorty ◽  
Meenal Kowshik ◽  
Indrani Talukdar
Keyword(s):  
Stem Cells ◽  
Stem Cell ◽  
Viral Vectors ◽  
Therapeutic Potential ◽  
Transfection Efficiency ◽  
Polymeric Nanoparticles ◽  
Sirna Delivery ◽  
Stem Cell Differentiation

Stem cell-based regenerative medicine holds exceptional therapeutic potential and hence the development of efficient techniques to enhance control over the rate of differentiation has been the focus of active research. One of the strategies to achieve this involves delivering siRNA into stem cells and exploiting the RNA interference (RNAi) mechanism. Transport of siRNA across the cell membrane is a challenge due to its anionic property, especially in primary human cells and stem cells. Moreover, naked siRNA incites immune responses, may cause off-target effects, exhibits low stability and is easily degraded by endonucleases in the bloodstream. Although siRNA delivery using viral vectors and electroporation has been used in stem cells, these methods demonstrate low transfection efficiency, cytotoxicity, immunogenicity, events of integration and may involve laborious customization. With the advent of nanotechnology, nanocarriers which act as novel gene delivery vehicles designed to overcome the problems associated with safety and practicality are being developed. The various nanomaterials that are currently being explored and discussed in this review include liposomes, carbon nanotubes, quantum dots, protein and peptide nanocarriers, magnetic nanoparticles, polymeric nanoparticles, etc. These nanodelivery agents exhibit advantages such as low immunogenic response, biocompatibility, design flexibility allowing for surface modification and functionalization, and control over the surface topography for achieving the desired rate of siRNA delivery and improved gene knockdown efficiency. This review also includes discussion on siRNA co-delivery with imaging agents, plasmid DNA, drugs etc. to achieve combined diagnostic and enhanced therapeutic functionality, both for in vitro and in vivo applications.

Bio-mimicking Shear Stress Environments for Enhancing Mesenchymal Stem Cell Differentiation

2020 ◽  
Vol 15 (5) ◽  
pp. 414-427
Author(s):  
Seep Arora ◽  
Akshaya Srinivasan ◽  
Chak Ming Leung ◽  
Yi-Chin Toh
Keyword(s):  
Stem Cells ◽  
Shear Stress ◽  
Stem Cell ◽  
Stem Cell Differentiation ◽  
In Vitro Differentiation ◽  
Msc Differentiation ◽  
Biophysical Cues

Mesenchymal stem cells (MSCs) are multipotent stromal cells, with the ability to differentiate into mesodermal (e.g., adipocyte, chondrocyte, hematopoietic, myocyte, osteoblast), ectodermal (e.g., epithelial, neural) and endodermal (e.g., hepatocyte, islet cell) lineages based on the type of induction cues provided. As compared to embryonic stem cells, MSCs hold a multitude of advantages from a clinical translation perspective, including ease of isolation, low immunogenicity and limited ethical concerns. Therefore, MSCs are a promising stem cell source for different regenerative medicine applications. The in vitro differentiation of MSCs into different lineages relies on effective mimicking of the in vivo milieu, including both biochemical and mechanical stimuli. As compared to other biophysical cues, such as substrate stiffness and topography, the role of fluid shear stress (SS) in regulating MSC differentiation has been investigated to a lesser extent although the role of interstitial fluid and vascular flow in regulating the normal physiology of bone, muscle and cardiovascular tissues is well-known. This review aims to summarise the current state-of-the-art regarding the role of SS in the differentiation of MSCs into osteogenic, cardiovascular, chondrogenic, adipogenic and neurogenic lineages. We will also highlight and discuss the potential of employing SS to augment the differentiation of MSCs to other lineages, where SS is known to play a role physiologically but has not yet been successfully harnessed for in vitro differentiation, including liver, kidney and corneal tissue lineage cells. The incorporation of SS, in combination with biochemical and biophysical cues during MSC differentiation, may provide a promising avenue to improve the functionality of the differentiated cells by more closely mimicking the in vivo milieu.

scholarly journals Decellularized Extracellular Matrix as anIn VitroModel to Study the Comprehensive Roles of the ECM in Stem Cell Differentiation

2016 ◽  
Vol 2016 ◽  
pp. 1-10 ◽  
Author(s):  
Takashi Hoshiba ◽  
Guoping Chen ◽  
Chiho Endo ◽  
Hiroka Maruyama ◽  
Miyuki Wakui ◽  
...  
Keyword(s):  
Stem Cells ◽  
Extracellular Matrix ◽  
Stem Cell ◽  
Cell Differentiation ◽  
Regenerative Medicine ◽  
Intracellular Signaling ◽  
Complex Structure ◽  
Stem Cell Differentiation

Stem cells are a promising cell source for regenerative medicine. Stem cell differentiation must be regulated for applications in regenerative medicine. Stem cells are surrounded by extracellular matrix (ECM)in vivo. The ECM is composed of many types of proteins and glycosaminoglycans that assemble into a complex structure. The assembly of ECM molecules influences stem cell differentiation through orchestrated intracellular signaling activated by many ECM molecules. Therefore, it is important to understand the comprehensive role of the ECM in stem cell differentiation as well as the functions of the individual ECM molecules. Decellularized ECM is a usefulin vitromodel for studying the comprehensive roles of ECM because it retains a native-like structure and composition. Decellularized ECM can be obtained fromin vivotissue ECM or ECM fabricated by cells culturedin vitro. It is important to select the correct decellularized ECM because each type has different properties. In this review, tissue-derived and cell-derived decellularized ECMs are compared asin vitroECM models to examine the comprehensive roles of the ECM in stem cell differentiation. We also summarize recent studies using decellularized ECM to determine the comprehensive roles of the ECM in stem cell differentiation.

scholarly journals Regulation of sarcomagenesis by the empty spiracles homeobox genes EMX1 and EMX2

2021 ◽  
Vol 12 (6) ◽  
Author(s):  
Manuel Pedro Jimenez-García ◽  
Antonio Lucena-Cacace ◽  
Daniel Otero-Albiol ◽  
Amancio Carnero
Keyword(s):  
Stem Cells ◽  
Stem Cell ◽  
Transcription Factors ◽  
Neural Crest ◽  
Tumor Suppressors ◽  
Homeobox Genes ◽  
Neuronal Cell ◽  
Cell Gene Expression

AbstractThe EMX (Empty Spiracles Homeobox) genes EMX1 and EMX2 are two homeodomain gene members of the EMX family of transcription factors involved in the regulation of various biological processes, such as cell proliferation, migration, and differentiation, during brain development and neural crest migration. They play a role in the specification of positional identity, the proliferation of neural stem cells, and the differentiation of certain neuronal cell phenotypes. In general, they act as transcription factors in early embryogenesis and neuroembryogenesis from metazoans to higher vertebrates. The EMX1 and EMX2’s potential as tumor suppressor genes has been suggested in some cancers. Our work showed that EMX1/EMX2 act as tumor suppressors in sarcomas by repressing the activity of stem cell regulatory genes (OCT4, SOX2, KLF4, MYC, NANOG, NES, and PROM1). EMX protein downregulation, therefore, induced the malignance and stemness of cells both in vitro and in vivo. In murine knockout (KO) models lacking Emx genes, 3MC-induced sarcomas were more aggressive and infiltrative, had a greater capacity for tumor self-renewal, and had higher stem cell gene expression and nestin expression than those in wild-type models. These results showing that EMX genes acted as stemness regulators were reproduced in different subtypes of sarcoma. Therefore, it is possible that the EMX genes could have a generalized behavior regulating proliferation of neural crest-derived progenitors. Together, these results indicate that the EMX1 and EMX2 genes negatively regulate these tumor-altering populations or cancer stem cells, acting as tumor suppressors in sarcoma.

scholarly journals “Empowering” Cardiac Cells via Stem Cell Derived Mitochondrial Transplantation- Does Age Matter?

2021 ◽  
Vol 22 (4) ◽  
pp. 1824
Author(s):  
Matthias Mietsch ◽  
Rabea Hinkel
Keyword(s):  
Stem Cells ◽  
Stem Cell ◽  
Treatment Strategies ◽  
Cardiac Cells ◽  
Aging Effects ◽  
Beneficial Effects ◽  
Micro Rnas ◽  
New Treatment

With cardiovascular diseases affecting millions of patients, new treatment strategies are urgently needed. The use of stem cell based approaches has been investigated during the last decades and promising effects have been achieved. However, the beneficial effect of stem cells has been found to being partly due to paracrine functions by alterations of their microenvironment and so an interesting field of research, the “stem- less” approaches has emerged over the last years using or altering the microenvironment, for example, via deletion of senescent cells, application of micro RNAs or by modifying the cellular energy metabolism via targeting mitochondria. Using autologous muscle-derived mitochondria for transplantations into the affected tissues has resulted in promising reports of improvements of cardiac functions in vitro and in vivo. However, since the targeted treatment group represents mainly elderly or otherwise sick patients, it is unclear whether and to what extent autologous mitochondria would exert their beneficial effects in these cases. Stem cells might represent better sources for mitochondria and could enhance the effect of mitochondrial transplantations. Therefore in this review we aim to provide an overview on aging effects of stem cells and mitochondria which might be important for mitochondrial transplantation and to give an overview on the current state in this field together with considerations worthwhile for further investigations.

Biomaterials Nano Geometry for Control of Stem Cell Differentiation

2009 ◽  
Vol 1239 ◽  
Author(s):  
Karla Brammer ◽  
Seunghan Oh ◽  
Sungho Jin
Keyword(s):  
Stem Cells ◽  
Stem Cell ◽  
Mesenchymal Stem Cell ◽  
Stem Cell Differentiation ◽  
Human Mesenchymal Stem Cell ◽  
Oxide Surface ◽  
Specific Cell ◽  
Implant Surface ◽  
Multipotent Stem Cells

AbstractTwo important goals in stem cell research are to control the cell proliferation without differentiation, and also to direct the differentiation into a specific cell lineage when desired. Recent studies indicate that the nanostructures substantially influence the stem cell behavior. It is well known that mesenchymal stem cells (MSCs) are multipotent stem cells that can differentiate into stromal lineages such as adipocyte, chondrocyte, fibroblast, myocyte, and osteoblast cell types. By examining the cellular behavior of MSCs cultured in vitro on nanostructures, some understanding of the effects that the nanostructures have on the stem cell’s response has been obtained. Here we demonstrate that TiO2 nanotubes produced by anodization on Ti implant surface can regulate human mesenchymal stem cell (hMSC) differentiation towards an osteoblast lineage in the absence of osteogenic inducing factors. Altering the dimensions of nanotubular-shaped titanium oxide surface structures independently allowed either augmented human mesenchymal stem cell (hMSC) adhesion at smaller diameter levels or a specific differentiation of hMSCs into osteoblasts using only the geometric cues. Small (˜30 nm diameter) nanotubes promoted adhesion without noticeable differentiation, while larger (˜70 - 100 nm diameter) nanotubes elicited a dramatic, ˜10 fold stem cell elongation, which induced cytoskeletal stress and selective differentiation into osteoblast-like cells, offering a promising nanotechnology-based route for novel orthopaedics-related hMSC treatments. The fact that a guided and preferential osteogenic differentiation of stem cells can be achieved using substrate nanotopography alone without using potentially toxic, differentiation-inducing chemical agents is significant, which can be useful for future development of novel and enhanced stem cell control and therapeutic implant development.

Sign in / Sign up

Export Citation Format

Share Document