scholarly journals The Urodele Limb Regeneration Blastema: The Cell Potential

2010 ◽  
Vol 10 ◽  
pp. 954-971 ◽  
Author(s):  
Kenyon S. Tweedell
Keyword(s):  
Stem Cells ◽  
Progenitor Cells ◽  
Cell Activation ◽  
Limb Regeneration ◽  
Cell Types ◽  
Dermal Fibroblasts ◽  
Specific Cell ◽  
Cell Potential ◽  
Developmental Potential ◽  
Regeneration Blastema

The developmental potential of the limb regeneration blastema, a mass of mesenchymal cells of mixed origins, was once considered as being pluripotent, capable of forming all cell types. Now evidence asserts that the blastema is a heterogeneous mixture of progenitor cells derived from tissues of the amputation site, with limited developmental potential, plus various stem cells with multipotent abilities. Many specialized cells, bone, cartilage, muscle, and Schwann cells, at the injury site undergo dedifferentiation to a progenitor state and maintain their cell lineage as they redifferentiate in the regenerate. Muscle satellite reserve stem cells that are active in repair of injured muscle may also dedifferentiate and contribute new muscle cells to the limb blastema. Other cells from the dermis act as multipotent stem cells that replenish dermal fibroblasts and differentiate into cartilage. The blastema primordium is a self-organized, equipotential system, but at the cellular level can compensate for specific cell loss. It is able to induce dedifferentiation of introduced exogenous cells and such cells may be transformed into new cell types. Indigenous cells of the blastema associated with amputated tissues may also transform or possibly transdifferentiate into new cell types. The blastema is a microenvironment that enables dedifferentiation, redifferentiation, transdifferentiation, and stem cell activation, leading to progenitor cells of the limb regenerate.

55 INFLUENCE OF DONOR CELL TYPE ON THE DEVELOPMENT OF PORCINE NUCLEAR TRANSFER EMBRYOS

2006 ◽  
Vol 18 (2) ◽  
pp. 136
Author(s):  
K. Lee ◽  
W. L. Fodor ◽  
Z. Machaty
Keyword(s):  
Stem Cells ◽  
Olfactory Bulb ◽  
Progenitor Cells ◽  
Nuclear Transfer ◽  
Cell Types ◽  
Blastocyst Stage ◽  
Blastocyst Formation ◽  
Developmental Potential ◽  
Differentiated Cells ◽  
Fetal Fibroblasts

Embryonic development after nuclear transfer is very low; the majority of cloned embryos do not survive the pre-implantation stage. Recent reports indicate that the characteristics of nuclear transfer embryos depend on the type of nuclear donor cells. It has been suggested that development after nuclear transfer improves if less differentiated cells are used as nuclear donors. The aim of the present study was to investigate the developmental potential of nuclear transfer embryos reconstructed using differentiated and non-differentiated cells. Two types of non-differentiated cells, skin stem cells and olfactory bulb progenitor cells, were used; fetal fibroblasts were used as differentiated control. Prior to nuclear transfer, the differentiated state of the cells was characterized by Oct-4 immunocytochemistry (Chemicon International, Inc., Temecula, CA, USA); Oct-4 is known to be expressed by pluripotent cells only. During nuclear transfer, the cells were transferred into the perivitelline space of in vitro-matured enucleated oocytes. After fusion, reconstructed oocytes were activated by an electrical pulse followed by incubation in 10 �g/mL cycloheximide and 5 �g/mL cytochalasin B for 5 h. The embryos were subsequently cultured in NCSU-23 medium for 6 days; their developmental data were recorded and compared by ANOVA. Non-differentiated cell types showed strong Oct-4 expression, whereas the marker protein was completely absent in fetal fibroblast cells. A total of 161 embryos were reconstructed using skin stem cells, 171 embryos from olfactory bulb progenitor cells, and 189 embryos from fibroblasts. Of the skin stem cell-derived embryos, 32.9% cleaved, and during subsequent culture, 5.6% developed to the morula/blastocyst stage. In the olfactory bulb progenitor cell group, 19.8% cleaved, and the percentage of embryos that developed to the morula/blastocyst stage was 4.7%. In the control group, 22.7% cleaved; the morula/blastocyst formation was 2.6%. Embryos reconstructed from skin stem cells showed superior cleavage rate compared to embryos from the other cell types (P < 0.05). Also, morula/blastocyst formation from skin stem cells was significantly higher than that from fetal fibroblasts (P < 0.05), and morula/blastocyst formation from olfactory bulb progenitor cell-derived embryos also tended to be higher compared to control embryos (P = 0.08). Furthermore, the formation of morulae/blastocysts per cleaved embryos was the highest in embryos reconstructed with olfactory bulb progenitor cells (23.5% vs. 17.0% using skin stem cells and 11.6% using fibroblasts) implying that embryos from olfactory bulb progenitor cells may have higher developmental potential in later stages of development. The results demonstrate that nuclei of different donor cells support development to various degrees and confirm previous reports that using non-differentiated cells as nuclear donors increases the efficiency of nuclear transfer in the pig.

338 IN VITRO GENERATION OF LENTOID BODIES FROM INDUCED PLURIPOTENT STEM CELLS OF TRANSGENIC MICE

2015 ◽  
Vol 27 (1) ◽  
pp. 257
Author(s):  
T. Anand ◽  
D. Kumar ◽  
T. R. Talluri ◽  
H. Niemann ◽  
W. A. Kues
Keyword(s):  
Stem Cells ◽  
Cell Types ◽  
Ips Cells ◽  
Sleeping Beauty ◽  
Specific Cell ◽  
Fluorescence Excitation ◽  
Ips Cell ◽  
Developmental Potential ◽  
Induced Pluripotent

Pluripotent cells have the developmental potential to generate all adult cell types, so ocular diseases resulting from the failure of specific cell types could be potentially treatable through the transplantation of differentiated cells derived from stem cells. The present study was conducted with the aim of generating a cataract model. We attempted to derive the induced pluripotent stem (iPS) cells from fibroblast cells of transgenic (crytom) mice carrying a transgenic construct-alphaA crystallin promoter driving the tandem dimer (td) Tomato marker transgene, integrated in the genome. The 4- to 6-week-old female crytom mice were selected, superovulated, and mated. The fetuses were recovered and examined on various different days (10.5 to 15.5 days postfertilization), and the reporter expression was found to be initiated 12.5 days postfertilization and the intensity was increased thereafter. The expression of tdTomato was confirmed in the fetuses by Western blotting. Murine embryonic fibroblast (MEF) cultures were generated and electroporated with a reprogramming transposon cassette carrying Yamanaka factors (OCT4, SOX2, KLF4, and MYC) and Sleeping Beauty transposase to generate iPS cells which were picked up and clonally expanded. The cells were confirmed by PCR for tdTomato in the genome and characterised for the expression of Oct4 and cryAB by immunofluorescence. The iPS cells were also injected into the nude CD1 mice to test for teratoma formation. The generated cells were allowed to differentiate spontaneously on 3 different types (viz. P19, NTERA, and STO) of cell lines as feeders, in the absence of LIF, and cells were expected to fluoresce if differentiated to eye lens lineage. After long-term cultures, the iPS cells were found to differentiate and form lentoid bodies which expressed tdTomato. Thus, alphaA crystallin-tdTomato construct was allowed following lens cell formation by specific fluorescence excitation in a spatial and temporal manner. The employment of cell type-specific reporters for establishing and optimizing targeted differentiation in vitro seems to be an efficient and generally applicable approach for developing differentiation protocols for desired cell populations. Hence a transgenic murine iPS cell line was generated which exhibited potential to be used as a model for eye cataracts and other eye abnormalities.

scholarly journals Vascular Stem Cells in Vascular Remodeling and Diseases

2013 ◽  
Vol 5 (3) ◽  
pp. 151
Author(s):  
Anna Meiliana ◽  
Andi Wijaya
Keyword(s):  
Stem Cells ◽  
Mesenchymal Stem Cells ◽  
Blood Vessels ◽  
Progenitor Cells ◽  
Tissue Expansion ◽  
Cell Types ◽  
Specific Cell ◽  
Vascular Stem Cells

BACKGROUND: Blood vessels are a source of stem and progenitor cells, which likely contribute to a variety of vascular processes and diseases. Emerging concepts in this field could influence therapeutic approaches to diseases of blood vessels such as atherosclerosis.CONTENT: Vascular Stem Cells (VSCs) field is only beginning to emerge, and thus, many issues regarding VSCs’s identity and function remain poorly understood. In fact, even after decades of intensive research, Mesenchymal Stem Cells (MSC), which is suggested to be VSCs, is still having many outstanding issues of its own. And, on top of this, likewise decades-long intensive pericyte research has not been able resolve the identity issue. While favors Adventitial Progenitor Cells (APCs) over pericytes as the likely VSC candidate, it should be pointed out that currently the opposite view (i.e., pericytes as VSCs) is more prevalent, and many excellent reviews, including a recent one, have discussed this issue extensively.SUMMARY: It has been postulated that, within the vasculature, APCs could differentiate into pericytes (CD34- CD31- CD140b+ SMA-), endothelial cells (CD34+ CD31+ CD140b- SMA-), and smooth muscle cells (SMCs) (CD34- CD31- CD140b- SMA+); and during tissue expansion or repair, APCs could also differentiate into tissue-specific cell types (e.g., muscle and fat) Thus, in vitro, APCs fulfill all criteria for being VSCs. Meanwhile, in vivo evidence is still limited and will require further investigation.KEYWORDS: vascular stem cells, VSC, mesenchymal stem cells, MSC, endothelial progenitor cells, EPC, adventitial progenitor cells, APC

scholarly journals Adult tissue-resident stem cells—fact or fiction?

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Deepa Bhartiya
Keyword(s):  
Stem Cells ◽  
Single Cell ◽  
Adult Stem Cells ◽  
Cell Types ◽  
Specific Cell ◽  
Tissue Specific ◽  
Cardiac Tissues ◽  
Adult Tissues ◽  
Resident Stem Cells ◽  
Abundant Cytoplasm

AbstractLife-long tissue homeostasis of adult tissues is supposedly maintained by the resident stem cells. These stem cells are quiescent in nature and rarely divide to self-renew and give rise to tissue-specific “progenitors” (lineage-restricted and tissue-committed) which divide rapidly and differentiate into tissue-specific cell types. However, it has proved difficult to isolate these quiescent stem cells as a physical entity. Recent single-cell RNAseq studies on several adult tissues including ovary, prostate, and cardiac tissues have not been able to detect stem cells. Thus, it has been postulated that adult cells dedifferentiate to stem-like state to ensure regeneration and can be defined as cells capable to replace lost cells through mitosis. This idea challenges basic paradigm of development biology regarding plasticity that a cell enters point of no return once it initiates differentiation. The underlying reason for this dilemma is that we are putting stem cells and somatic cells together while processing for various studies. Stem cells and adult mature cell types are distinct entities; stem cells are quiescent, small in size, and with minimal organelles whereas the mature cells are metabolically active and have multiple organelles lying in abundant cytoplasm. As a result, they do not pellet down together when centrifuged at 100–350g. At this speed, mature cells get collected but stem cells remain buoyant and can be pelleted by centrifuging at 1000g. Thus, inability to detect stem cells in recently published single-cell RNAseq studies is because the stem cells were unknowingly discarded while processing and were never subjected to RNAseq. This needs to be kept in mind before proposing to redefine adult stem cells.

scholarly journals Histone Acetyltransferases and Stem Cell Identity

Cancers ◽  
2021 ◽  
Vol 13 (10) ◽  
pp. 2407
Author(s):  
Ruicen He ◽  
Arthur Dantas ◽  
Karl Riabowol
Keyword(s):  
Stem Cells ◽  
Stem Cell ◽  
Cell Fate ◽  
Epigenetic Modification ◽  
Cell Types ◽  
Histone Acetyltransferases ◽  
Specific Cell ◽  
Cell Fates ◽  
Cell Identity ◽  
Hematopoietic Stem

Acetylation of histones is a key epigenetic modification involved in transcriptional regulation. The addition of acetyl groups to histone tails generally reduces histone-DNA interactions in the nucleosome leading to increased accessibility for transcription factors and core transcriptional machinery to bind their target sequences. There are approximately 30 histone acetyltransferases and their corresponding complexes, each of which affect the expression of a subset of genes. Because cell identity is determined by gene expression profile, it is unsurprising that the HATs responsible for inducing expression of these genes play a crucial role in determining cell fate. Here, we explore the role of HATs in the maintenance and differentiation of various stem cell types. Several HAT complexes have been characterized to play an important role in activating genes that allow stem cells to self-renew. Knockdown or loss of their activity leads to reduced expression and or differentiation while particular HATs drive differentiation towards specific cell fates. In this study we review functions of the HAT complexes active in pluripotent stem cells, hematopoietic stem cells, muscle satellite cells, mesenchymal stem cells, neural stem cells, and cancer stem cells.

scholarly journals Collagen gel three-dimensional matrices combined with adhesive proteins stimulate neuronal differentiation of mesenchymal stem cells

2011 ◽  
Vol 8 (60) ◽  
pp. 998-1010 ◽  
Author(s):  
Jae Ho Lee ◽  
Hye-Sun Yu ◽  
Gil-Su Lee ◽  
Aeri Ji ◽  
Jung Keun Hyun ◽  
...  
Keyword(s):  
Stem Cells ◽  
Mesenchymal Stem Cells ◽  
Neuronal Differentiation ◽  
Large Population ◽  
Three Dimensional ◽  
Collagen Gel ◽  
Cell Types ◽  
Specific Cell ◽  
Neuronal Outgrowth ◽  
Adhesive Proteins

Three-dimensional gel matrices provide specialized microenvironments that mimic native tissues and enable stem cells to grow and differentiate into specific cell types. Here, we show that collagen three-dimensional gel matrices prepared in combination with adhesive proteins, such as fibronectin (FN) and laminin (LN), provide significant cues to the differentiation into neuronal lineage of mesenchymal stem cells (MSCs) derived from rat bone marrow. When cultured within either a three-dimensional collagen gel alone or one containing either FN or LN, and free of nerve growth factor (NGF), the MSCs showed the development of numerous neurite outgrowths. These were, however, not readily observed in two-dimensional culture without the use of NGF. Immunofluorescence staining, western blot and fluorescence-activated cell sorting analyses demonstrated that a large population of cells was positive for NeuN and glial fibrillary acidic protein, which are specific to neuronal cells, when cultured in the three-dimensional collagen gel. The dependence of the neuronal differentiation of MSCs on the adhesive proteins containing three-dimensional gel matrices is considered to be closely related to focal adhesion kinase (FAK) activation through integrin receptor binding, as revealed by an experiment showing no neuronal outgrowth in the FAK-knockdown cells and stimulation of integrin β1 gene. The results provided herein suggest the potential role of three-dimensional collagen-based gel matrices combined with adhesive proteins in the neuronal differentiation of MSCs, even without the use of chemical differentiation factors. Furthermore, these findings suggest that three-dimensional gel matrices might be useful as nerve-regenerative scaffolds.

scholarly journals Cellular Functions of OCT-3/4 Regulated by Ubiquitination in Proliferating Cells

Cancers ◽  
2020 ◽  
Vol 12 (3) ◽  
pp. 663
Author(s):  
Kwang-Hyun Baek ◽  
Jihye Choi ◽  
Chang-Zhu Pei
Keyword(s):  
Stem Cells ◽  
Cellular Proliferation ◽  
Critical Role ◽  
Embryonic Stem ◽  
Cell Types ◽  
Ubiquitin Proteasome System ◽  
Specific Cell ◽  
Cellular Mechanisms ◽  
Proliferating Cells ◽  
Proliferation And Differentiation

Octamer-binding transcription factor 3/4 (OCT-3/4), which is involved in the tumorigenesis of somatic cancers, has diverse functions during cancer development. Overexpression of OCT-3/4 has been detected in various human somatic tumors, indicating that OCT-3/4 activation may contribute to the development and progression of cancers. Stem cells can undergo self-renewal, pluripotency, and reprogramming with the help of at least four transcription factors, OCT-3/4, SRY box-containing gene 2 (SOX2), Krüppel-like factor 4 (KLF4), and c-MYC. Of these, OCT-3/4 plays a critical role in maintenance of undifferentiated state of embryonic stem cells (ESCs) and in production of induced pluripotent stem cells (iPSCs). Stem cells can undergo partitioning through mitosis and separate into specific cell types, three embryonic germ layers: the endoderm, the mesoderm, and the trophectoderm. It has been demonstrated that the stability of OCT-3/4 is mediated by the ubiquitin-proteasome system (UPS), which is one of the key cellular mechanisms for cellular homeostasis. The framework of the mechanism is simple, but the proteolytic machinery is complicated. Ubiquitination promotes protein degradation, and ubiquitination of OCT-3/4 leads to regulation of cellular proliferation and differentiation. Therefore, it is expected that OCT-3/4 may play a key role in proliferation and differentiation of proliferating cells.

Abstract 65: Latrophilin-2 is a Specific Cell-surface Marker for Cardiac Progenitor Cells and Specifies Cardiac Lineage Commitment and Development

2016 ◽  
Vol 119 (suppl_1) ◽  
Author(s):  
Hyun-Jai Cho ◽  
Choon-Soo Lee ◽  
Jin-Woo Lee ◽  
Jung-Kyu Han ◽  
Han-Mo Yang ◽  
...  
Keyword(s):  
Stem Cells ◽  
Cell Surface ◽  
Progenitor Cells ◽  
Pluripotent Stem Cells ◽  
Cardiac Development ◽  
Cardiac Differentiation ◽  
Specific Cell ◽  
Specific Marker ◽  
Cardiac Progenitor Cells ◽  
Cardiac Lineage

Backgrounds: The identification of a lineage-specific marker plays a pivotal role in understanding developmental process and is utilized to isolate a certain cell type with high purity for the therapeutic purpose. We here report a new cardiac-specific marker, and demonstrate its functional significance in the cardiac development. Methods and Results: When mouse pluripotent stem cells (ES and iPS cells) were stimulated with BMP4, Activin A, bFGF and VEGF, they differentiated into cardiac cells. To screen cell-surface expressing molecules on cardiac progenitor cells compared to undifferentiated mouse iPS and ES cells, we isolated Flk1+/PDGFRa+ cells at differentiation day 4 and performed microarray analysis. Among candidates, we identified a new G protein-coupled receptor, Latrophilin-2 (LPHN2) whose signaling pathway and its effect on cardiac differentiation is unknown. In sorting experiments under cardiac differentiation condition, LPHN2+ cells derived from pluripotent stem cells strongly expressed cardiac-related genes (Mesp1, Nkx2.5, aMHC and cTnT) and exclusively gave rise to beating cardiomyocytes, as compared with LPHN2- cells. LPHN2-/- mice revealed embryonically lethal and huge defects in cardiac development. Interestingly, LPHN2+/- heterozygotes were alive and fertile. For the purpose of cardiac regeneration, we transplanted iPS-derived LPHN2+ cells into the infarcted heart of adult mice. LPHN2+ cells differentiated into cardiomyocytes, and systolic function of left ventricle was improved and infarct size was reduced. We confirmed LPHN2 expression on human iPS and ES cell-derived cardiac progenitor cells and human heart. Conclusions: We demonstrate that LPHN2 is a functionally significant and cell-surface expressing marker for both mouse and human cardiac progenitor and cardiomyocytes. Our findings provide a valuable tool for isolating cardiac lineage cells from pluripotent stem cells and an insight into cardiac development and regeneration.

scholarly journals Adaptation to oxygen deprivation in cultures of human pluripotent stem cells, endothelial progenitor cells, and umbilical vein endothelial cells

2010 ◽  
Vol 298 (6) ◽  
pp. C1527-C1537 ◽  
Author(s):  
Hasan Erbil Abaci ◽  
Rachel Truitt ◽  
Eli Luong ◽  
German Drazer ◽  
Sharon Gerecht
Keyword(s):  
Stem Cells ◽  
Endothelial Cells ◽  
Oxygen Consumption ◽  
Progenitor Cells ◽  
Pluripotent Stem Cells ◽  
Cell Types ◽  
Cellular Responses ◽  
Glut 1 ◽  
Lower Oxygen ◽  
Oxygen Tensions

Hypoxia plays an important role in vascular development through hypoxia-inducible factor-1α (HIF-1α) accumulation and downstream pathway activation. We sought to explore the in vitro response of cultures of human embryonic stem cells (hESCs), induced pluripotent stem cells (iPSCs), human endothelial progenitor cells (hEPCs), and human umbilical cord vein endothelial cells (HUVECs) to normoxic and hypoxic oxygen tensions. We first measured dissolved oxygen (DO) in the media of adherent cultures in atmospheric (21% O2), physiological (5% O2), and hypoxic oxygen conditions (1% O2). In cultures of both hEPCs and HUVECs, lower oxygen consumption was observed when cultured in 1% O2. At each oxygen tension, feeder-free cultured hESCs and iPSCs were found to consume comparable amounts of oxygen. Transport analysis revealed that the oxygen uptake rate (OUR) of hESCs and iPSCs decreased distinctly as DO availability decreased, whereas the OUR of all cell types was found to be low when cultured in 1% O2, demonstrating cell adaptation to lower oxygen tensions by limiting oxygen consumption. Next, we examined HIF-1α accumulation and the expression of target genes, including VEGF and angiopoietins ( ANGPT; angiogenic response), GLUT-1 (glucose transport), BNIP3, and BNIP3L (autophagy and apoptosis). Accumulations of HIF-1α were detected in all four cell lines cultured in 1% O2. Corresponding upregulation of VEGF, ANGPT2, and GLUT-1 was observed in response to HIF-1α accumulation, whereas upregulation of ANGPT1 was detected only in hESCs and iPSCs. Upregulation of BNIP3 and BNIP3L was detected in all cells after 24-h culture in hypoxic conditions, whereas apoptosis was not detectable using flow cytometry analysis, suggesting that BNIP3 and BNIP3L can lead to cell autophagy rather than apoptosis. These results demonstrate adaptation of all cell types to hypoxia but different cellular responses, suggesting that continuous measurements and control over oxygen environments will enable us to guide cellular responses.

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