PGE2 /EP4 Signaling Controls the Transfer of the Mammary Stem Cell State by Lipid Rafts in Extracellular Vesicles.

PubMed

Lin, Meng-Chieh; Chen, Shih-Yin; Tsai, Ho-Min; He, Pei-Lin; Lin, Yen-Chun; Herschman, Harvey; Li, Hua-Jung

2017-02-01

Prostaglandin E 2 (PGE 2 )-initiated signaling contributes to stem cell homeostasis and regeneration. However, it is unclear how PGE 2 signaling controls cell stemness. This study identifies a previously unknown mechanism by which PGE 2 /prostaglandin E receptor 4 (EP 4 ) signaling regulates multiple signaling pathways (e.g., PI3K/Akt signaling, TGFβ signaling, Wnt signaling, EGFR signaling) which maintain the basal mammary stem cell phenotype. A shift of basal mammary epithelial stem cells (MaSCs) from a mesenchymal/stem cell state to a non-basal-MaSC state occurs in response to prostaglandin E receptor 4 (EP 4 ) antagonism. EP 4 antagonists elicit release of signaling components, by controlling their trafficking into extracellular vesicles/exosomes in a lipid raft/caveolae-dependent manner. Consequently, EP 4 antagonism indirectly inactivates, through induced extracellular vesicle/exosome release, pathways required for mammary epithelial stem cell homeostasis, e.g. canonical/noncanonical Wnt, TGFβ and PI3K/Akt pathways. EP 4 antagonism causes signaling receptors and signaling components to shift from non-lipid raft fractions to lipid raft fractions, and to then be released in EP 4 antagonist-induced extracellular vesicles/exosomes, resulting in the loss of the stem cell state by mammary epithelial stem cells. In contrast, luminal mammary epithelial cells can acquire basal stem cell properties following ingestion of EP 4 antagonist-induced stem cell extracellular vesicles/exosomes, and can then form mammary glands. These findings demonstrate that PGE 2 /EP 4 signaling controls homeostasis of mammary epithelial stem cells through regulating extracellular vesicle/exosome release. Reprogramming of mammary epithelial cells can result from EP 4 -mediated stem cell property transfer by extracellular vesicles/exosomes containing caveolae-associated proteins, between mammary basal and luminal epithelial cells. Stem Cells 2017;35:425-444. © 2016 The Authors STEM CELLS published by Wiley Periodicals, Inc. on behalf of AlphaMed Press.

Fluorescent labelling of intestinal epithelial cells reveals independent long-lived intestinal stem cells in a crypt

DOE Office of Scientific and Technical Information (OSTI.GOV)

Horita, Nobukatsu; Tsuchiya, Kiichiro, E-mail: kii.gast@tmd.ac.jp; Hayashi, Ryohei

Highlights: • Lentivirus mixed with Matrigel enables direct infection of intestinal organoids. • Our original approach allows the marking of a single stem cell in a crypt. • Time-lapse imaging shows the dynamics of a single stem cell. • Our lentivirus transgene system demonstrates plural long-lived stem cells in a crypt. - Abstract: Background and aims: The dynamics of intestinal stem cells are crucial for regulation of intestinal function and maintenance. Although crypt stem cells have been identified in the intestine by genetic marking methods, identification of plural crypt stem cells has not yet been achieved as they are visualisedmore » in the same colour. Methods: Intestinal organoids were transferred into Matrigel® mixed with lentivirus encoding mCherry. The dynamics of mCherry-positive cells was analysed using time-lapse imaging, and the localisation of mCherry-positive cells was analysed using 3D immunofluorescence. Results: We established an original method for the introduction of a transgene into an organoid generated from mouse small intestine that resulted in continuous fluorescence of the mCherry protein in a portion of organoid cells. Three-dimensional analysis using confocal microscopy showed a single mCherry-positive cell in an organoid crypt that had been cultured for >1 year, which suggested the presence of long-lived mCherry-positive and -negative stem cells in the same crypt. Moreover, a single mCherry-positive stem cell in a crypt gave rise to both crypt base columnar cells and transit amplifying cells. Each mCherry-positive and -negative cell contributed to the generation of organoids. Conclusions: The use of our original lentiviral transgene system to mark individual organoid crypt stem cells showed that long-lived plural crypt stem cells might independently serve as intestinal epithelial cells, resulting in the formation of a completely functional villus.« less

Progressive Chromatin Condensation and H3K9 Methylation Regulate the Differentiation of Embryonic and Hematopoietic Stem Cells

DOE PAGES

Ugarte, Fernando; Sousae, Rebekah; Cinquin, Bertrand; ...

2015-10-17

Epigenetic regulation serves as the basis for stem cell differentiation into distinct cell types, but it is unclear how global epigenetic changes are regulated during this process. Here, we tested the hypothesis that global chromatin organization affects the lineage potential of stem cells and that manipulation of chromatin dynamics influences stem cell function. Using nuclease sensitivity assays, we found a progressive decrease in chromatin digestion among pluripotent embryonic stem cells (ESCs), multipotent hematopoietic stem cells (HSCs), and mature hematopoietic cells. Quantitative high-resolution microscopy revealed that ESCs contain significantly more euchromatin than HSCs, with a further reduction in mature cells. Increasedmore » cellular maturation also led to heterochromatin localization to the nuclear periphery. Functionally, prevention of heterochromatin formation by inhibition of the histone methyltransferase G9A resulted in delayed HSC differentiation. Lastly, our results demonstrate global chromatin rearrangements during stem cell differentiation and that heterochromatin formation by H3K9 methylation regulates HSC differentiation.« less

Progressive Chromatin Condensation and H3K9 Methylation Regulate the Differentiation of Embryonic and Hematopoietic Stem Cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ugarte, Fernando; Sousae, Rebekah; Cinquin, Bertrand

Epigenetic regulation serves as the basis for stem cell differentiation into distinct cell types, but it is unclear how global epigenetic changes are regulated during this process. Here, we tested the hypothesis that global chromatin organization affects the lineage potential of stem cells and that manipulation of chromatin dynamics influences stem cell function. Using nuclease sensitivity assays, we found a progressive decrease in chromatin digestion among pluripotent embryonic stem cells (ESCs), multipotent hematopoietic stem cells (HSCs), and mature hematopoietic cells. Quantitative high-resolution microscopy revealed that ESCs contain significantly more euchromatin than HSCs, with a further reduction in mature cells. Increasedmore » cellular maturation also led to heterochromatin localization to the nuclear periphery. Functionally, prevention of heterochromatin formation by inhibition of the histone methyltransferase G9A resulted in delayed HSC differentiation. Lastly, our results demonstrate global chromatin rearrangements during stem cell differentiation and that heterochromatin formation by H3K9 methylation regulates HSC differentiation.« less

CD34+ Testicular Stromal Cells Support Long-Term Expansion of Embryonic and Adult Stem and Progenitor Cells

PubMed Central

Kim, Jiyeon; Seandel, Marco; Falciatori, Ilaria; Wen, Duancheng; Rafii, Shahin

2010-01-01

Stem cells reside in specialized microenvironments created by supporting stromal cells that orchestrate self-renewal and lineage-specific differentiation. However, the precise identity of the cellular and molecular pathways that support self-renewal of stem cells is not known. For example, long-term culture of prototypical stem cells, such as adult spermatogonial stem and progenitor cells (SPCs), in vitro has been impeded by the lack of an optimal stromal cell line that initiates and sustains proliferation of these cells. Indeed, current methods, including the use of mouse embryonic fibroblasts (MEFs), have not been efficient and have generally led to inconsistent results. Here, we report the establishment of a novel CD34-positive cell line, referred to as JK1, derived from mouse testicular stromal cells that not only facilitated long-term SPC culture but also allowed faithful generation of SPCs and multipotent stem cells. SPCs generated on JK1 maintained key features of germ line stem cells, including expression of PLZF, DAZL, and GCNA. Furthermore, these feeders also promoted the long-term cultivation of other types of primitive cells including multi-potent adult spermatogonial-derived stem cells, pluripotent murine embryonic stem cells, and embryonic germ cells derived from primordial germ cells. Stem cells could be passaged serially and still maintained expression of characteristic markers such as OCT4 and NANOG in vitro, as well as the ability to generate all three germ layers in vivo. These results indicate that the JK1 cell line is capable of promoting long-term culture of primitive cells. As such, this cell line allows for identification of stromal-derived factors that support long-term proliferation of various types of stem cells and constitutes a convenient alternative to other types of feeder layers. PMID:18669907

Regulatory mechanism of protein metabolic pathway during the differentiation process of chicken male germ cell.

PubMed

Li, Dong; Zuo, Qisheng; Lian, Chao; Zhang, Lei; Shi, Qingqing; Zhang, Zhentao; Wang, Yingjie; Ahmed, Mahmoud F; Tang, Beibei; Xiao, Tianrong; Zhang, Yani; Li, Bichun

2015-08-01

We explored the regulatory mechanism of protein metabolism during the differentiation process of chicken male germ cells and provide a basis for improving the induction system of embryonic stem cell differentiation to male germ cells in vitro. We sequenced the transcriptome of embryonic stem cells, primordial germ cells, and spermatogonial stem cells with RNA sequencing (RNA-Seq), bioinformatics analysis methods, and detection of the key genes by quantitative reverse transcription PCR (qRT-PCR). Finally, we found 16 amino acid metabolic pathways enriched in the biological metabolism during the differentiation process of embryonic stem cells to primordial germ cells and 15 amino acid metabolic pathways enriched in the differentiation stage of primordial germ cells to spermatogonial stem cells. We found three pathways, arginine-proline metabolic pathway, tyrosine metabolic pathway, and tryptophan metabolic pathway, significantly enriched in the whole differentiation process of embryonic stem cells to spermatogonial stem cells. Moreover, for these three pathways, we screened key genes such as NOS2, ADC, FAH, and IDO. qRT-PCR results showed that the expression trend of these genes were the same to RNA-Seq. Our findings showed that the three pathways and these key genes play an important role in the differentiation process of embryonic stem cells to male germ cells. These results provide basic information for improving the induction system of embryonic stem cell differentiation to male germ cells in vitro.

Redox regulation of plant stem cell fate.

PubMed

Zeng, Jian; Dong, Zhicheng; Wu, Haijun; Tian, Zhaoxia; Zhao, Zhong

2017-10-02

Despite the importance of stem cells in plant and animal development, the common mechanisms of stem cell maintenance in both systems have remained elusive. Recently, the importance of hydrogen peroxide (H 2 O 2 ) signaling in priming stem cell differentiation has been extensively studied in animals. Here, we show that different forms of reactive oxygen species (ROS) have antagonistic roles in plant stem cell regulation, which were established by distinct spatiotemporal patterns of ROS-metabolizing enzymes. The superoxide anion (O2·-) is markedly enriched in stem cells to activate WUSCHEL and maintain stemness, whereas H 2 O 2 is more abundant in the differentiating peripheral zone to promote stem cell differentiation. Moreover, H 2 O 2 negatively regulates O2·- biosynthesis in stem cells, and increasing H 2 O 2 levels or scavenging O2·- leads to the termination of stem cells. Our results provide a mechanistic framework for ROS-mediated control of plant stem cell fate and demonstrate that the balance between O2·- and H 2 O 2 is key to stem cell maintenance and differentiation. © 2017 The Authors.

The Endogenous GRP78 Interactome in Human Head and Neck Cancers: A Deterministic Role of Cell Surface GRP78 in Cancer Stemness.

PubMed

Chen, Hsin-Ying; Chang, Joseph Tung-Chieh; Chien, Kun-Yi; Lee, Yun-Shien; You, Guo-Rung; Cheng, Ann-Joy

2018-01-11

Cell surface glucose regulated protein 78 (GRP78), an endoplasmic reticulum (ER) chaperone, was suggested to be a cancer stem cell marker, but the influence of this molecule on cancer stemness is poorly characterized. In this study, we developed a mass spectrometry platform to detect the endogenous interactome of GRP78 and investigated its role in cancer stemness. The interactome results showed that cell surface GRP78 associates with multiple molecules. The influence of cell population heterogeneity of head and neck cancer cell lines (OECM1, FaDu, and BM2) according to the cell surface expression levels of GRP78 and the GRP78 interactome protein, Progranulin, was investigated. The four sorted cell groups exhibited distinct cell cycle distributions, asymmetric/symmetric cell divisions, and different relative expression levels of stemness markers. Our results demonstrate that cell surface GRP78 promotes cancer stemness, whereas drives cells toward a non-stemlike phenotype when it chaperones Progranulin. We conclude that cell surface GRP78 is a chaperone exerting a deterministic influence on cancer stemness.

[Genetic regulation of plant shoot stem cells].

PubMed

Al'bert, E V; Ezhova, T A

2013-02-01

This article describes the main features of plant stem cells and summarizes the results of studies of the genetic control of stem cell maintenance in the apical meristem of the shoot. It is demonstrated that the WUS-CLV gene system plays a key role in the maintenance of shoot apical stem cells and the formation of adventitious buds and somatic embryos. Unconventional concepts of plant stem cells are considered.

Epirubicin-Adsorbed Nanodiamonds Kill Chemoresistant Hepatic Cancer Stem Cells

PubMed Central

2015-01-01

Chemoresistance is a primary cause of treatment failure in cancer and a common property of tumor-initiating cancer stem cells. Overcoming mechanisms of chemoresistance, particularly in cancer stem cells, can markedly enhance cancer therapy and prevent recurrence and metastasis. This study demonstrates that the delivery of Epirubicin by nanodiamonds is a highly effective nanomedicine-based approach to overcoming chemoresistance in hepatic cancer stem cells. The potent physical adsorption of Epirubicin to nanodiamonds creates a rapidly synthesized and stable nanodiamond–drug complex that promotes endocytic uptake and enhanced tumor cell retention. These attributes mediate the effective killing of both cancer stem cells and noncancer stem cells in vitro and in vivo. Enhanced treatment of both tumor cell populations results in an improved impairment of secondary tumor formation in vivo compared with treatment by unmodified chemotherapeutics. On the basis of these results, nanodiamond-mediated drug delivery may serve as a powerful method for overcoming chemoresistance in cancer stem cells and markedly improving overall treatment against hepatic cancers. PMID:25437772

Rats, cats, and elephants, but still no unicorn: induced pluripotent stem cells from new species.

PubMed

Trounson, Alan

2009-01-09

Two independent studies in this issue of Cell Stem Cell (Liao et al., 2009; Li et al., 2009) derive rat induced pluripotent stem cells (iPSCs). In one report, the method used results in rat and human iPSCs that exhibit phenotypic traits similar to mouse embryonic stem cells.

Ocular Stem Cell Research from Basic Science to Clinical Application: A Report from Zhongshan Ophthalmic Center Ocular Stem Cell Symposium

PubMed Central

Ouyang, Hong; Goldberg, Jeffrey L.; Chen, Shuyi; Li, Wei; Xu, Guo-Tong; Li, Wei; Zhang, Kang; Nussenblatt, Robert B.; Liu, Yizhi; Xie, Ting; Chan, Chi-Chao; Zack, Donald J.

2016-01-01

Stem cells hold promise for treating a wide variety of diseases, including degenerative disorders of the eye. The eye is an ideal organ for stem cell therapy because of its relative immunological privilege, surgical accessibility, and its being a self-contained system. The eye also has many potential target diseases amenable to stem cell-based treatment, such as corneal limbal stem cell deficiency, glaucoma, age-related macular degeneration (AMD), and retinitis pigmentosa (RP). Among them, AMD and glaucoma are the two most common diseases, affecting over 200 million people worldwide. Recent results on the clinical trial of retinal pigment epithelial (RPE) cells from human embryonic stem cells (hESCs) and induced pluripotent stem cells (iPSCs) in treating dry AMD and Stargardt’s disease in the US, Japan, England, and China have generated great excitement and hope. This marks the beginning of the ocular stem cell therapy era. The recent Zhongshan Ophthalmic Center Ocular Stem Cell Symposium discussed the potential applications of various stem cell types in stem cell-based therapies, drug discoveries and tissue engineering for treating ocular diseases. PMID:27102165

Recent Progress in Stem Cell Modification for Cardiac Regeneration

PubMed Central

Voronina, Natalia; Steinhoff, Gustav

2018-01-01

During the past decades, stem cell-based therapy has acquired a promising role in regenerative medicine. The application of novel cell therapeutics for the treatment of cardiovascular diseases could potentially achieve the ambitious aim of effective cardiac regeneration. Despite the highly positive results from preclinical studies, data from phase I/II clinical trials are inconsistent and the improvement of cardiac remodeling and heart performance was found to be quite limited. The major issues which cardiac stem cell therapy is facing include inefficient cell delivery to the site of injury, accompanied by low cell retention and weak effectiveness of remaining stem cells in tissue regeneration. According to preclinical and clinical studies, various stem cells (adult stem cells, embryonic stem cells, and induced pluripotent stem cells) represent the most promising cell types so far. Beside the selection of the appropriate cell type, researchers have developed several strategies to produce “second-generation” stem cell products with improved regenerative capacity. Genetic and nongenetic modifications, chemical and physical preconditioning, and the application of biomaterials were found to significantly enhance the regenerative capacity of transplanted stem cells. In this review, we will give an overview of the recent developments in stem cell engineering with the goal to facilitate stem cell delivery and to promote their cardiac regenerative activity. PMID:29535769

Genetics Home Reference: polycythemia vera

MedlinePlus

... mutations occur in the DNA of a hematopoietic stem cell . These stem cells are located in the bone marrow and ... controlling the production of blood cells from hematopoietic stem cells. JAK2 gene mutations result in the production ...

Reduced hematopoietic stem cell frequency predicts outcome in acute myeloid leukemia.

PubMed

Wang, Wenwen; Stiehl, Thomas; Raffel, Simon; Hoang, Van T; Hoffmann, Isabel; Poisa-Beiro, Laura; Saeed, Borhan R; Blume, Rachel; Manta, Linda; Eckstein, Volker; Bochtler, Tilmann; Wuchter, Patrick; Essers, Marieke; Jauch, Anna; Trumpp, Andreas; Marciniak-Czochra, Anna; Ho, Anthony D; Lutz, Christoph

2017-09-01

In patients with acute myeloid leukemia and low percentages of aldehyde-dehydrogenase-positive cells, non-leukemic hematopoietic stem cells can be separated from leukemic cells. By relating hematopoietic stem cell frequencies to outcome we detected poor overall- and disease-free survival of patients with low hematopoietic stem cell frequencies. Serial analysis of matched diagnostic and follow-up samples further demonstrated that hematopoietic stem cells increased after chemotherapy in patients who achieved durable remissions. However, in patients who eventually relapsed, hematopoietic stem cell numbers decreased dramatically at the time of molecular relapse demonstrating that hematopoietic stem cell levels represent an indirect marker of minimal residual disease, which heralds leukemic relapse. Upon transplantation in immune-deficient mice cases with low percentages of hematopoietic stem cells of our cohort gave rise to leukemic or no engraftment, whereas cases with normal hematopoietic stem cell levels mostly resulted in multi-lineage engraftment. Based on our experimental data, we propose that leukemic stem cells have increased niche affinity in cases with low percentages of hematopoietic stem cells. To validate this hypothesis, we developed new mathematical models describing the dynamics of healthy and leukemic cells under different regulatory scenarios. These models suggest that the mechanism leading to decreases in hematopoietic stem cell frequencies before leukemic relapse must be based on expansion of leukemic stem cells with high niche affinity and the ability to dislodge hematopoietic stem cells. Thus, our data suggest that decreasing numbers of hematopoietic stem cells indicate leukemic stem cell persistence and the emergence of leukemic relapse. Copyright© 2017 Ferrata Storti Foundation.

Stem cells and female reproduction.

PubMed

Du, Hongling; Taylor, Hugh S

2009-02-01

Several recent findings in stem cell biology have resulted in new opportunities for the treatment of reproductive disease. Endometrial regeneration can be driven by bone marrow derived stem cells. This finding has potential implications for the treatment of uterine disorders. It also supports a new theory for the etiology of endometriosis. The ovaries have been shown to contain stem cells that form oocytes in adults and can be cultured in vitro to develop mature oocytes. Stem cells from the fetus have been demonstrated to lead to microchimerism in the mother and implicated in several maternal diseases. Additionally the placenta may be another source of hematopoietic stem cell. Finally endometrial derived stem cells have been demonstrated to differentiate into non-reproductive tissues. While we are just beginning to understand stem cells and many key questions remain, the potential advantages of stem cells in reproductive biology and medicine are apparent.

Dipeptide species regulate p38MAPK–Smad3 signalling to maintain chronic myelogenous leukaemia stem cells

PubMed Central

Naka, Kazuhito; Jomen, Yoshie; Ishihara, Kaori; Kim, Junil; Ishimoto, Takahiro; Bae, Eun-Jin; Mohney, Robert P.; Stirdivant, Steven M.; Oshima, Hiroko; Oshima, Masanobu; Kim, Dong-Wook; Nakauchi, Hiromitsu; Takihara, Yoshihiro; Kato, Yukio; Ooshima, Akira; Kim, Seong-Jin

2015-01-01

Understanding the specific survival of the rare chronic myelogenous leukaemia (CML) stem cell population could provide a target for therapeutics aimed at eradicating these cells. However, little is known about how survival signalling is regulated in CML stem cells. In this study, we survey global metabolic differences between murine normal haematopoietic stem cells (HSCs) and CML stem cells using metabolomics techniques. Strikingly, we show that CML stem cells accumulate significantly higher levels of certain dipeptide species than normal HSCs. Once internalized, these dipeptide species activate amino-acid signalling via a pathway involving p38MAPK and the stemness transcription factor Smad3, which promotes CML stem cell maintenance. Importantly, pharmacological inhibition of dipeptide uptake inhibits CML stem cell activity in vivo. Our results demonstrate that dipeptide species support CML stem cell maintenance by activating p38MAPK–Smad3 signalling in vivo, and thus point towards a potential therapeutic target for CML treatment. PMID:26289811

Stem cells: intellectual property issues in regenerative medicine.

PubMed

Zachariades, Nicholas A

2013-12-01

The topic of stem cells for use in regenerative medicine, especially embryonic stem cells, inspires much debate, discussion, and outrage as it slices through the very core moral values of society. These social and moral issues have, in turn, resulted in government policies that have influenced the study of stem cells in regenerative medicine.

Hematopoietic Stem Cell Transplantation in Primary Immunodeficiency Patients in the Black Sea Region of Turkey.

PubMed

Yıldıran, Alişan; Çeliksoy, Mehmet Halil; Borte, Stephan; Güner, Şükrü Nail; Elli, Murat; Fışgın, Tunç; Özyürek, Emel; Sancak, Recep; Oğur, Gönül

2017-12-01

Hematopoietic stem cell transplantation is a promising curative therapy for many combined primary immunodeficiencies and phagocytic disorders. We retrospectively reviewed pediatric cases of patients diagnosed with primary immunodeficiencies and scheduled for hematopoietic stem cell transplantation. We identified 22 patients (median age, 6 months; age range, 1 month to 10 years) with various diagnoses who received hematopoietic stem cell transplantation. The patient diagnoses included severe combined immunodeficiency (n=11), Chediak-Higashi syndrome (n=2), leukocyte adhesion deficiency (n=2), MHC class 2 deficiency (n=2), chronic granulomatous syndrome (n=2), hemophagocytic lymphohistiocytosis (n=1), Wiskott-Aldrich syndrome (n=1), and Omenn syndrome (n=1). Of the 22 patients, 7 received human leukocyte antigen-matched related hematopoietic stem cell transplantation, 12 received haploidentical hematopoietic stem cell transplantation, and 2 received matched unrelated hematopoietic stem cell transplantation. The results showed that 5 patients had graft failure. Fourteen patients survived, yielding an overall survival rate of 67%. Screening newborn infants for primary immunodeficiency diseases may result in timely administration of hematopoietic stem cell transplantation.

The king is dead, long live the king: entering a new era of stem cell research and clinical development.

PubMed

Ichim, Thomas; Riordan, Neil H; Stroncek, David F

2011-12-20

In mid November the biopharma industry was shocked by the announcement from Geron that they were ending work on embryonic stem cell research and therapy. For more than 10 years the public image of all stem cell research has been equated with embryonic stem cells. Unfortunately, a fundamentally important medical and financial fact was being ignored: embryonic stem cell therapy is extremely immature. In parallel to efforts in embryonic stem cell research and development, scientists and physicians in the field of adult stem cells realized that the natural role of adult stem cells in the body is to promote healing and to act like endogenous "repair cells" and, as a result, numerous companies have entered the field of adult stem cell therapy with the goal of expanding numbers of adult stem cells for administration to patients with various conditions. In contrast to embryonic stem cells, which are extremely expensive and potentially dangerous, adult cell cells are inexpensive and have an excellent safety record when used in humans. Many studies are now showing that adult stem cells are practical, patient-applicable, therapeutics that are very close to being available for incorporation into the practice of medicine. These events signal the entrance of the field of stem cells into a new era: an era where hype and misinformation no longer triumph over economic and medical realities.

Human induced pluripotent stem cells can reach complete terminal maturation: in vivo and in vitro evidence in the erythropoietic differentiation model

PubMed Central

Kobari, Ladan; Yates, Frank; Oudrhiri, Noufissa; Francina, Alain; Kiger, Laurent; Mazurier, Christelle; Rouzbeh, Shaghayegh; El-Nemer, Wassim; Hebert, Nicolas; Giarratana, Marie-Catherine; François, Sabine; Chapel, Alain; Lapillonne, Hélène; Luton, Dominique; Bennaceur-Griscelli, Annelise; Douay, Luc

2012-01-01

Background Human induced pluripotent stem cells offer perspectives for cell therapy and research models for diseases. We applied this approach to the normal and pathological erythroid differentiation model by establishing induced pluripotent stem cells from normal and homozygous sickle cell disease donors. Design and Methods We addressed the question as to whether these cells can reach complete erythroid terminal maturation notably with a complete switch from fetal to adult hemoglobin. Sickle cell disease induced pluripotent stem cells were differentiated in vitro into red blood cells and characterized for their terminal maturation in terms of hemoglobin content, oxygen transport capacity, deformability, sickling and adherence. Nucleated erythroblast populations generated from normal and pathological induced pluripotent stem cells were then injected into non-obese diabetic severe combined immunodeficiency mice to follow the in vivo hemoglobin maturation. Results We observed that in vitro erythroid differentiation results in predominance of fetal hemoglobin which rescues the functionality of red blood cells in the pathological model of sickle cell disease. We observed, in vivo, the switch from fetal to adult hemoglobin after infusion of nucleated erythroid precursors derived from either normal or pathological induced pluripotent stem cells into mice. Conclusions These results demonstrate that human induced pluripotent stem cells: i) can achieve complete terminal erythroid maturation, in vitro in terms of nucleus expulsion and in vivo in terms of hemoglobin maturation; and ii) open the way to generation of functionally corrected red blood cells from sickle cell disease induced pluripotent stem cells, without any genetic modification or drug treatment. PMID:22733021

Stromal cell-derived factor 1 (SDF-1) accelerated skin wound healing by promoting the migration and proliferation of epidermal stem cells.

PubMed

Guo, Rui; Chai, Linlin; Chen, Liang; Chen, Wenguang; Ge, Liangpeng; Li, Xiaoge; Li, Hongli; Li, Shirong; Cao, Chuan

2015-06-01

Epidermal stem cells could contribute to skin repair through the migration of cells from the neighboring uninjured epidermis, infundibulum, hair follicle, or sebaceous gland. However, little is known about the factors responsible for the complex biological processes in wound healing. Herein, we will show that the attracting chemokine, SDF-1/CXCR4, is a major regulator involved in the migration of epidermal stem cells during wound repair. We found that the SDF-1 levels were markedly increased at the wound margins following injury and CXCR4 expressed in epidermal stem cells and proliferating epithelial cells. Blocking the SDF-1/CXCR4 axis resulted in a significant reduction in epidermal stem cell migration toward SDF-1 in vitro and delayed wound healing in vivo, while an SDF-1 treatment enhanced epidermal stem cell migration and proliferation and accelerated wound healing. These results provide direct evidence that SDF-1 promotes epidermal stem cell migration, accelerates skin regeneration, and makes the development of new regenerative therapeutic strategies for wound healing possible.

Induction of muscle stem cell quiescence by the secreted niche factor Oncostatin M.

PubMed

Sampath, Srinath C; Sampath, Srihari C; Ho, Andrew T V; Corbel, Stéphane Y; Millstone, Joshua D; Lamb, John; Walker, John; Kinzel, Bernd; Schmedt, Christian; Blau, Helen M

2018-04-18

The balance between stem cell quiescence and proliferation in skeletal muscle is tightly controlled, but perturbed in a variety of disease states. Despite progress in identifying activators of stem cell proliferation, the niche factor(s) responsible for quiescence induction remain unclear. Here we report an in vivo imaging-based screen which identifies Oncostatin M (OSM), a member of the interleukin-6 family of cytokines, as a potent inducer of muscle stem cell (MuSC, satellite cell) quiescence. OSM is produced by muscle fibers, induces reversible MuSC cell cycle exit, and maintains stem cell regenerative capacity as judged by serial transplantation. Conditional OSM receptor deletion in satellite cells leads to stem cell depletion and impaired regeneration following injury. These results identify Oncostatin M as a secreted niche factor responsible for quiescence induction, and for the first time establish a direct connection between induction of quiescence, stemness, and transplantation potential in solid organ stem cells.

In vivo stem cell tracking with imageable nanoparticles that bind bioorthogonal chemical receptors on the stem cell surface.

PubMed

Lee, Sangmin; Yoon, Hwa In; Na, Jin Hee; Jeon, Sangmin; Lim, Seungho; Koo, Heebeom; Han, Sang-Soo; Kang, Sun-Woong; Park, Soon-Jung; Moon, Sung-Hwan; Park, Jae Hyung; Cho, Yong Woo; Kim, Byung-Soo; Kim, Sang Kyoon; Lee, Taekwan; Kim, Dongkyu; Lee, Seulki; Pomper, Martin G; Kwon, Ick Chan; Kim, Kwangmeyung

2017-09-01

It is urgently necessary to develop reliable non-invasive stem cell imaging technology for tracking the in vivo fate of transplanted stem cells in living subjects. Herein, we developed a simple and well controlled stem cell imaging method through a combination of metabolic glycoengineering and bioorthogonal copper-free click chemistry. Firstly, the exogenous chemical receptors containing azide (-N 3 ) groups were generated on the surfaces of stem cells through metabolic glycoengineering using metabolic precursor, tetra-acetylated N-azidoacetyl-d-mannosamine(Ac 4 ManNAz). Next, bicyclo[6.1.0]nonyne-modified glycol chitosan nanoparticles (BCN-CNPs) were prepared as imageable nanoparticles to deliver different imaging agents. Cy5.5, iron oxide nanoparticles and gold nanoparticles were conjugated or encapsulated to BCN-CNPs for optical, MR and CT imaging, respectively. These imageable nanoparticles bound chemical receptors on the Ac 4 ManNAz-treated stem cell surface specifically via bioorthogonal copper-free click chemistry. Then they were rapidly taken up by the cell membrane turn-over mechanism resulting in higher endocytic capacity compared non-specific uptake of nanoparticles. During in vivo animal test, BCN-CNP-Cy5.5-labeled stem cells could be continuously tracked by non-invasive optical imaging over 15 days. Furthermore, BCN-CNP-IRON- and BCN-CNP-GOLD-labeled stem cells could be efficiently visualized using in vivo MR and CT imaging demonstrating utility of our stem cell labeling method using chemical receptors. These results conclude that our method based on metabolic glycoengineering and bioorthogonal copper-free click chemistry can stably label stem cells with diverse imageable nanoparticles representing great potential as new stem cell imaging technology. Copyright © 2017 Elsevier Ltd. All rights reserved.

Automatic cell cloning assay for determining the clonogenic capacity of cancer and cancer stem-like cells.

PubMed

Fedr, Radek; Pernicová, Zuzana; Slabáková, Eva; Straková, Nicol; Bouchal, Jan; Grepl, Michal; Kozubík, Alois; Souček, Karel

2013-05-01

The clonogenic assay is a well-established in vitro method for testing the survival and proliferative capability of cells. It can be used to determine the cytotoxic effects of various treatments including chemotherapeutics and ionizing radiation. However, this approach can also characterize cells with different phenotypes and biological properties, such as stem cells or cancer stem cells. In this study, we implemented a faster and more precise method for assessing the cloning efficiency of cancer stem-like cells that were characterized and separated using a high-speed cell sorter. Cell plating onto a microplate using an automatic cell deposition unit was performed in a single-cell or dilution rank mode by the fluorescence-activated cell sorting method. We tested the new automatic cell-cloning assay (ACCA) on selected cancer cell lines and compared it with the manual approach. The obtained results were also compared with the results of the limiting dilution assay for different cell lines. We applied the ACCA to analyze the cloning capacity of different subpopulations of prostate and colon cancer cells based on the expression of the characteristic markers of stem (CD44 and CD133) and cancer stem cells (TROP-2, CD49f, and CD44). Our results revealed that the novel ACCA is a straightforward approach for determining the clonogenic capacity of cancer stem-like cells identified in both cell lines and patient samples. Copyright © 2013 International Society for Advancement of Cytometry.

Mesenchymal Stem Cell Therapy for the Treatment of Vocal Fold Scarring: A Systematic Review of Preclinical Studies

PubMed Central

Wingstrand, Vibe Lindeblad; Jensen, David H.; Bork, Kristian; Sebbesen, Lars; Balle, Jesper; Fischer-Nielsen, Anne; von Buchwald, Christian

2016-01-01

Objectives Therapy with mesenchymal stem cells exhibits potential for the development of novel interventions for many diseases and injuries. The use of mesenchymal stem cells in regenerative therapy for vocal fold scarring exhibited promising results to reduce stiffness and enhance the biomechanical properties of injured vocal folds. This study evaluated the biomechanical effects of mesenchymal stem cell therapy for the treatment of vocal fold scarring. Data Sources PubMed, Embase, the Cochrane Library and Google Scholar were searched. Methods Controlled studies that assessed the biomechanical effects of mesenchymal stem cell therapy for the treatment of vocal fold scarring were included. Primary outcomes were viscoelastic properties and mucosal wave amplitude. Results Seven preclinical animal studies (n = 152 single vocal folds) were eligible for inclusion. Evaluation of viscoelastic parameters revealed a decreased dynamic viscosity (η’) and elastic modulus (G’), i.e., decreased resistance and stiffness, in scarred vocal folds treated with mesenchymal stem cells compared to non-treated scarred vocal folds. Mucosal wave amplitude was increased in scarred vocal folds treated with mesenchymal stem cells vs. non-treated scarred vocal folds. Conclusion The results from these studies suggest an increased regenerative effect of therapy with mesenchymal stem cells for scarred vocal folds and are encouraging for further clinical studies. PMID:27631373

Lower Oncogenic Potential of Human Mesenchymal Stem Cells Derived from Cord Blood Compared to Induced Pluripotent Stem Cells

PubMed Central

Foroutan, T.; Najmi, M.; Kazemi, N.; Hasanlou, M.; Pedram, A.

2015-01-01

Background: In regenerative medicine, use of each of the mesenchymal stem cells derived from bone marrow, cord blood, and adipose tissue, has several cons and pros. Mesenchymal stem cells derived from cord blood have been considered the best source for precursor transplantation. Direct reprogramming of a somatic cell into induced pluripotent stem cells by over-expression of 6 transcription factors Oct4, Sox2, Klf4, lin28, Nanog, and c-Myc has great potential for regenerative medicine, eliminating the ethical issues of embryonic stem cells and the rejection problems of using non-autologous cells. Objective: To compare reprogramming and pluripotent markers OCT4, Sox-2, c-Myc, Klf4, Nanog, and lin28 in mesenchymal stem cells derived from cord blood and induced pluripotent stem cells. Methods: We analyzed the expression level of OCT4, Sox-2, c-Myc, Klf4, Nanog and lin28 genes in human mesenchymal stem cells derived from cord blood and induced pluripotent stem cells by cell culture and RT-PCR. Results: The expression level of pluripotent genes OCT4 and Sox-2, Nanog and lin28 in mesenchymal stem cells derived from cord blood were significantly higher than those in induced pluripotent stem cells. In contrast to OCT-4A and Sox-2, Nanog and lin28, the expression level of oncogenic factors c-Myc and Klf4 were significantly higher in induced pluripotent stem cells than in mesenchymal stem cells derived from cord blood. Conclusion: It could be concluded that mesenchymal stem cells derived from human cord blood have lower oncogenic potential compared to induced pluripotent stem cells. PMID:26306155

Eckol suppresses maintenance of stemness and malignancies in glioma stem-like cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hyun, Kyung-Hwan; Yoon, Chang-Hwan; Kim, Rae-Kwon

A subpopulation of cancer cells with stem cell properties is responsible for tumor maintenance and progression, and may contribute to resistance to anticancer treatments. Thus, compounds that target cancer stem-like cells could be usefully applied to destroy cancer. In this study, we investigated the effect of Eckol, a phlorotannin compound, on stemness and malignancies in glioma stem-like cells. To determine whether Eckol targets glioma stem-like cells, we examined whether Eckol treatment could change the expression levels of glioma stem-like cell markers and self-renewal-related proteins as well as the sphere forming ability, and the sensitivity to anticancer treatments. Alterations in themore » malignant properties of sphere-derived cells by Eckol were also investigated by soft-agar colony forming assay, by xenograft assay in nude mice, and by cell invasion assay. Treatment of sphere-forming glioma cells with Eckol effectively decreased the sphere formation as well as the CD133{sup +} cell population. Eckol treatment suppressed expression of the glioma stem-like cell markers and the self-renewal-related proteins without cell death. Moreover, treatment of glioma stem-like cells with Eckol significantly attenuated anchorage-independent growth on soft agar and tumor formation in xenograft mice. Importantly, Eckol treatment effectively reduced the resistance of glioma stem-like cells to ionizing radiation and temozolomide. Treatment of glioma stem-like cells with Eckol markedly blocked both phosphoinositide 3-kinase-Akt and Ras-Raf-1-Erk signaling pathways. These results indicate that the natural phlorotannin Eckol suppresses stemness and malignancies in glioma stem-like cells, and thereby makes glioma stem-like cells more sensitive to anticancer treatments, providing novel therapeutic strategies targeting specifically cancer stem-like cells.« less

Therapeutic strategies involving uterine stem cells in reproductive medicine.

PubMed

Simoni, Michael; Taylor, Hugh S

2018-06-01

The current review provides an update on recent advances in stem cell biology relevant to female reproduction. Stem cells are undifferentiated cells that often serve as a reservoir of cells to regenerate tissue in settings or injury or cell loss. The endometrium has progenitor stem cells that can replace all of the endometrium during each menstrual cycle. In addition, multipotent endometrial cells replace these progenitor cells when depleted. Recruitment of stem cells from outside of the uterus occurs in setting of increased demand such as ischemia or injury. Bone marrow-derived multipotent stem cells are recruited to the uterus by estrogen or injury-induced expression of the chemokine CXCL12. In the setting of overwhelming injury, especially in the setting of low estrogen levels, there may be insufficient stem cell recruitment to adequately repair the uterus resulting in conditions such as Asherman syndrome or other endometrial defects. In contrast, excessive recruitment of stem cells underlies endometriosis. Enhanced understanding of stem-cell mobilization, recruitment, and engraftment has created the possibility of improved therapy for endometrial defects and endometriosis through enhanced manipulation of stem-cell trafficking. Further, the normal endometrium is a rich source of multipotent stem cells that can be used for numerous applications in regenerative medicine beyond reproduction. A better understanding of reproductive stem-cell biology may allow improved treatment of endometrial disease such as Asherman syndrome and other endometrial receptivity defects. Inhibiting stem-cell mobilization may also be helpful in endometriosis therapy. Finally, endometrial derived multipotent stem cells may play a crucial role in cell therapy for regenerative medicine.

Stemness of spermatogonial stem cells encapsulated in alginate hydrogel during cryopreservation.

PubMed

Pirnia, A; Parivar, K; Hemadi, M; Yaghmaei, P; Gholami, M

2017-06-01

This study investigated the effect of spermatogonial stem cell encapsulated in alginate hydrogel during cryopreservation, as cells were protected against damage during cryopreservation within the hydrogel. Spermatogonial stem cells were isolated from the testes of Balb/c mice pups (6 days old), purified in laminin-coated dishes and CD90.1 microbeads, encapsulated in alginate hydrogel and then cryopreserved. After thawing, cell viability and Spermatogonial stem cell (SSC) colony diameter were evaluated. After RNA was isolated and cDNA was synthesised, the expression of stemness genes was considered using RT real-time PCR. Finally, spermatogonial stem cells labelled with BrdU were transplanted to busulfan azoospermic mouse models. Lin28a and Sall4 genes were significantly upregulated after cryopreservation in alginate hydrogel. However, cell viability was significantly decreased. The diameter of colonies consisting of spermatogonial stem cells freeze-thawed in alginate microbeads showed no significant difference with fresh spermatogonial stem cells and the control group. The injection of freeze-thawed spermatogonial stem cells encapsulated in alginate hydrogel resulted in spermatogenesis recovery. Alginate mimics the extracellular matrices (ECM) for spermatogonial stem cells; therefore, it can support stemness potential during the cell cryopreservation process and restart spermatogenesis after transplantation. © 2016 Blackwell Verlag GmbH.

IL-17B activated mesenchymal stem cells enhance proliferation and migration of gastric cancer cells.

PubMed

Bie, Qingli; Zhang, Bin; Sun, Caixia; Ji, Xiaoyun; Barnie, Prince Amoah; Qi, Chen; Peng, Jingjing; Zhang, Danyi; Zheng, Dong; Su, Zhaoliang; Wang, Shengjun; Xu, Huaxi

2017-03-21

Mesenchymal stem cells are important cells in tumor microenvironment. We have previously demonstrated that IL-17B/IL-17RB signal promoted progression of gastric cancer. In this study, we further explored the effect of IL-17B on mesenchymal stem cells in tumor microenvironment and its impact on the tumor progression. The results showed that IL-17B induced the expression of stemness-related genes Nanog, Sox2, and Oct4 in mesenchymal stem cells and enhanced its tumor-promoting effect. The supernatant from cultured mesenchymal stem cells after treating with exogenous rIL-17B promoted the proliferation and migration of MGC-803, therefor suggesting that rIL-17B might promote mesenchymal stem cells to produce soluble factors. In addition, rIL-17B also activated the NF-κΒ, STAT3, β-catenin pathway in mesenchymal stem cells. Our data revealed a new mechanism that IL-17B enhanced the progression of gastric cancer by activating mesenchymal stem cells.

A Phenotype-Based RNAi Screening for Ras-ERK/MAPK Signaling-Associated Stem Cell Regulators in C. elegans.

PubMed

Lee, Myon-Hee; Yoon, Dong Suk

2017-01-01

Stem cells have the ability to self-renew and to generate differentiated cell types. A regulatory network that controls this balance is critical for stem cell homeostasis and normal animal development. Particularly, Ras-ERK/MAPK signaling pathway is critical for stem cell self-renewal and differentiation in mammals, including humans. Aberrant regulation of Ras-ERK/MAPK signaling pathway results in either stem cell or overproliferation. Therefore, the identification of Ras-ERK/MAPK signaling pathway-associated regulators is critical to understand the mechanism of stem cell (possibly cancer stem cell) control. In this report, using the nematode C. elegans mutants, we developed a methodology for a phenotype-based RNAi screening that identifies stem cell regulator genes associated with Ras-ERK/MAPK signaling within the context of a whole organism. Importantly, this phenotype-based RNAi screening can be applied for other stem cell-associated signaling pathways such as Wnt/β-catenin and Notch using the C. elegans.

Mycoplasma Infection Alters Cancer Stem Cell Properties in Vitro.

PubMed

Gedye, Craig; Cardwell, Tracy; Dimopoulos, Nektaria; Tan, Bee Shin; Jackson, Heather; Svobodová, Suzanne; Anaka, Matthew; Behren, Andreas; Maher, Christopher; Hofmann, Oliver; Hide, Winston; Caballero, Otavia; Davis, Ian D; Cebon, Jonathan

2016-02-01

Cancer cell lines can be useful to model cancer stem cells. Infection with Mycoplasma species is an insidious problem in mammalian cell culture. While investigating stem-like properties in early passage melanoma cell lines, we noted poorly reproducible results from an aliquot of a cell line that was later found to be infected with Mycoplasma hyorhinis. Deliberate infection of other early passage melanoma cell lines aliquots induced variable and unpredictable effects on expression of putative cancer stem cell markers, clonogenicity, proliferation and global gene expression. Cell lines established in stem cell media (SCM) were equally susceptible. Mycoplasma status is rarely reported in publications using cultured cells to study the cancer stem cell hypothesis. Our work highlights the importance of surveillance for Mycoplasma infection while using any cultured cells to interrogate tumor heterogeneity.

Stem cells for cardiac repair: an introduction

PubMed Central

du Pré, Bastiaan C; Doevendans, Pieter A; van Laake, Linda W

2013-01-01

Cardiovascular disease is a major cause of morbidity and mortality throughout the world. Most cardiovascular diseases, such as ischemic heart disease and cardiomyopathy, are associated with loss of functional cardiomyocytes. Unfortunately, the heart has a limited regenerative capacity and is not able to replace these cardiomyocytes once lost. In recent years, stem cells have been put forward as a potential source for cardiac regeneration. Pre-clinical studies that use stem cell-derived cardiac cells show promising results. The mechanisms, though, are not well understood, results have been variable, sometimes transient in the long term, and often without a mechanistic explanation. There are still several major hurdles to be taken. Stem cell-derived cardiac cells should resemble original cardiac cell types and be able to integrate in the damaged heart. Integration requires administration of stem cell-derived cardiac cells at the right time using the right mode of delivery. Once delivered, transplanted cells need vascularization, electrophysiological coupling with the injured heart, and prevention of immunological rejection. Finally, stem cell therapy needs to be safe, reproducible, and affordable. In this review, we will give an introduction to the principles of stem cell based cardiac repair. PMID:23888179

Targeting colon cancer stem cells using a new curcumin analogue, GO-Y030.

PubMed

Lin, L; Liu, Y; Li, H; Li, P-K; Fuchs, J; Shibata, H; Iwabuchi, Y; Lin, J

2011-07-12

Persistent activation of signal transducers and activators of transcription 3 (STAT3) is commonly detected in many types of cancer, including colon cancer. To date, whether STAT3 is activated and the effects of STAT3 inhibition by a newly developed curcumin analogue, GO-Y030, in colon cancer stem cells are still unknown. Flow cytometry was used to isolate colon cancer stem cells, which are characterised by both aldehyde dehydrogenase (ALDH)-positive and CD133-positive subpopulations (ALDH(+)/CD133(+)). The levels of STAT3 phosphorylation and the effects of STAT3 inhibition by a newly developed curcumin analogue, GO-Y030, that targets STAT3 in colon cancer stem cells were examined. Our results observed that ALDH(+)/CD133(+) colon cancer cells expressed higher levels of phosphorylated STAT3 than ALDH-negative/CD133-negative colon cancer cells, suggesting that STAT3 is activated in colon cancer stem cells. GO-Y030 and curcumin inhibited STAT3 phosphorylation, cell viability, tumoursphere formation in colon cancer stem cells. GO-Y030 also reduced STAT3 downstream target gene expression and induced apoptosis in colon cancer stem cells. Furthermore, GO-Y030 suppressed tumour growth of cancer stem cells from both SW480 and HCT-116 colon cancer cell lines in the mouse model. Our results indicate that STAT3 is a novel therapeutic target in colon cancer stem cells, and inhibition of activated STAT3 in cancer stem cells by GO-Y030 may offer an effective treatment for colorectal cancer.

Linking stem cell function and growth pattern of intestinal organoids.

PubMed

Thalheim, Torsten; Quaas, Marianne; Herberg, Maria; Braumann, Ulf-Dietrich; Kerner, Christiane; Loeffler, Markus; Aust, Gabriela; Galle, Joerg

2018-01-15

Intestinal stem cells (ISCs) require well-defined signals from their environment in order to carry out their specific functions. Most of these signals are provided by neighboring cells that form a stem cell niche, whose shape and cellular composition self-organize. Major features of this self-organization can be studied in ISC-derived organoid culture. In this system, manipulation of essential pathways of stem cell maintenance and differentiation results in well-described growth phenotypes. We here provide an individual cell-based model of intestinal organoids that enables a mechanistic explanation of the observed growth phenotypes. In simulation studies of the 3D structure of expanding organoids, we investigate interdependences between Wnt- and Notch-signaling which control the shape of the stem cell niche and, thus, the growth pattern of the organoids. Similar to in vitro experiments, changes of pathway activities alter the cellular composition of the organoids and, thereby, affect their shape. Exogenous Wnt enforces transitions from branched into a cyst-like growth pattern; known to occur spontaneously during long term organoid expansion. Based on our simulation results, we predict that the cyst-like pattern is associated with biomechanical changes of the cells which assign them a growth advantage. The results suggest ongoing stem cell adaptation to in vitro conditions during long term expansion by stabilizing Wnt-activity. Our study exemplifies the potential of individual cell-based modeling in unraveling links between molecular stem cell regulation and 3D growth of tissues. This kind of modeling combines experimental results in the fields of stem cell biology and cell biomechanics constituting a prerequisite for a better understanding of tissue regeneration as well as developmental processes. Copyright © 2017 Elsevier Inc. All rights reserved.

Personalized Regenerative Medicine.

PubMed

Arjmand, Babak; Goodarzi, Parisa; Mohamadi-Jahani, Fereshteh; Falahzadeh, Khadijeh; Larijani, Bagher

2017-03-01

Personalized medicine as a novel field of medicine refers to the prescription of specific therapeutics procedure for an individual. This approach has established based on pharmacogenetic and pharmacogenomic information and data. The terms precision and personalized medicines are sometimes applied interchangeably. However, there has been a shift from "personalized medicine" towards "precision medicine". Although personalized medicine emerged from pharmacogenetics, nowadays it covers many fields of healthcare. Accordingly, regenerative medicine and cellular therapy as the new fields of medicine use cell-based products in order to develop personalized treatments. Different sources of stem cells including mesenchymal stem cells, embryonic stem cells and induced pluripotent stem cells (iPSCs) have been considered in targeted therapies which could give many advantages. iPSCs as the novel and individual pluripotent stem cells have been introduced as the appropriate candidates for personalized cell therapies. Cellular therapies can provide a personalized approach. Because of person-to-person and population differences in the result of stem cell therapy, individualized cellular therapy must be adjusted according to the patient specific profile, in order to achieve best therapeutic results and outcomes. Several factors should be considered to achieve personalized stem cells therapy such as, recipient factors, donor factors, and the overall body environment in which the stem cells could be active and functional. In addition to these factors, the source of stem cells must be carefully chosen based on functional and physical criteria that lead to optimal outcomes.

Dynamics associated with spontaneous differentiation of ovarian stem cells in vitro

PubMed Central

2014-01-01

Background Recent studies suggest that ovarian germ line stem cells replenish oocyte-pool in adult stage, and challenge the central doctrine of ‘fixed germ cell pool’ in mammalian reproductive biology. Two distinct populations of spherical stem cells with high nucleo-cytoplasmic ratio have been recently identified in the adult mammalian ovary surface epithelium (OSE) including nuclear OCT-4A positive very small embryonic-like (VSELs) and cytoplasmic OCT-4 expressing ovarian germ stem cells (OGSCs). Three weeks culture of scraped OSE cells results in spontaneous differentiation of the stem cells into oocyte-like, parthenote-like, embryoid body-like structures and also embryonic stem cell-like colonies whereas epithelial cells attach and transform into a bed of mesenchymal cells. Present study was undertaken, to further characterize ovarian stem cells and to comprehend better the process of spontaneous differentiation of ovarian stem cells into oocyte-like structures in vitro. Methods Ovarian stem cells were enriched by immunomagnetic sorting using SSEA-4 as a cell surface marker and were further characterized. Stem cells and clusters of OGSCs (reminiscent of germ cell nests in fetal ovaries), were characterized by immuno-localization for stem and germ cell specific markers and spontaneous differentiation in OSE cultures was studied by live cell imaging. Results Differential expression of markers specific for pluripotent VSELs (nuclear OCT-4A, SSEA-4, CD133), OGSCs (cytoplasmic OCT-4) primordial germ cells (FRAGILIS, STELLA, VASA) and germ cells (DAZL, GDF-9, SCP-3) were studied. Within one week of culture, stem cells became bigger in size, developed abundant cytoplasm, differentiated into germ cells, revealed presence of Balbiani body-like structure (mitochondrial cloud) and exhibited characteristic cytoplasmic streaming. Conclusions Presence of germ cell nests, Balbiani body-like structures and cytoplasmic streaming extensively described during fetal ovary development, are indeed well recapitulated during in vitro oogenesis in adult OSE cultures along with characteristic expression of stem/germ cell/oocyte markers. Further studies are required to assess the genetic integrity of in vitro derived oocytes before harnessing their clinical potential. Advance in our knowledge about germ cell differentiation from stem cells will enable researchers to design better in vitro strategies which in turn may have relevance to reproductive biology and regenerative medicine. PMID:24568237

A Comparative Transcriptomic Analysis Reveals Conserved Features of Stem Cell Pluripotency in Planarians and Mammals

PubMed Central

Labbé, Roselyne M.; Irimia, Manuel; Currie, Ko W.; Lin, Alexander; Zhu, Shu Jun; Brown, David D.R.; Ross, Eric J.; Voisin, Veronique; Bader, Gary D.; Blencowe, Benjamin J.; Pearson, Bret J.

2014-01-01

Many long-lived species of animals require the function of adult stem cells throughout their lives. However, the transcriptomes of stem cells in invertebrates and vertebrates have not been compared, and consequently, ancestral regulatory circuits that control stem cell populations remain poorly defined. In this study, we have used data from high-throughput RNA sequencing to compare the transcriptomes of pluripotent adult stem cells from planarians with the transcriptomes of human and mouse pluripotent embryonic stem cells. From a stringently defined set of 4,432 orthologs shared between planarians, mice and humans, we identified 123 conserved genes that are ≥5-fold differentially expressed in stem cells from all three species. Guided by this gene set, we used RNAi screening in adult planarians to discover novel stem cell regulators, which we found to affect the stem cell-associated functions of tissue homeostasis, regeneration, and stem cell maintenance. Examples of genes that disrupted these processes included the orthologs of TBL3, PSD12, TTC27, and RACK1. From these analyses, we concluded that by comparing stem cell transcriptomes from diverse species, it is possible to uncover conserved factors that function in stem cell biology. These results provide insights into which genes comprised the ancestral circuitry underlying the control of stem cell self-renewal and pluripotency. PMID:22696458

The effect of incorporation of SDF-1alpha into PLGA scaffolds on stem cell recruitment and the inflammatory response.

PubMed

Thevenot, Paul T; Nair, Ashwin M; Shen, Jinhui; Lotfi, Parisa; Ko, Cheng-Yu; Tang, Liping

2010-05-01

Despite significant advances in the understanding of tissue responses to biomaterials, most implants are still plagued by inflammatory responses which can lead to fibrotic encapsulation. This is of dire consequence in tissue engineering, where seeded cells and bioactive components are separated from the native tissue, limiting the regenerative potential of the design. Additionally, these interactions prevent desired tissue integration and angiogenesis, preventing functionality of the design. Recent evidence supports that mesenchymal stem cells (MSC) and hematopoietic stem cells (HSC) can have beneficial effects which alter the inflammatory responses and improve healing. The purpose of this study was to examine whether stem cells could be targeted to the site of biomaterial implantation and whether increasing local stem cell responses could improve the tissue response to PLGA scaffold implants. Through incorporation of SDF-1alpha through factor adsorption and mini-osmotic pump delivery, the host-derived stem cell response can be improved resulting in 3X increase in stem cell populations at the interface for up to 2 weeks. These interactions were found to significantly alter the acute mast cell responses, reducing the number of mast cells and degranulated mast cells near the scaffold implants. This led to subsequent downstream reduction in the inflammatory cell responses, and through altered mast cell activation and stem cell participation, increased angiogenesis and decreased fibrotic responses to the scaffold implants. These results support that enhanced recruitment of autologous stem cells can improve the tissue responses to biomaterial implants through modifying/bypassing inflammatory cell responses and jumpstarting stem cell participation in healing at the implant interface. Copyright 2010 Elsevier Ltd. All rights reserved.

The Effect of Incorporation of SDF-1α into PLGA Scaffolds on Stem Cell Recruitment and the Inflammatory Response

PubMed Central

Thevenot, Paul; Nair, Ashwin; Shen, Jinhui; Lotfi, Parisa; Ko, Cheng Yu; Tang, Liping

2010-01-01

Despite significant advances in the understanding of tissue responses to biomaterials, most implants are still plagued by inflammatory responses which can lead to fibrotic encapsulation. This is of dire consequence in tissue engineering, where seeded cells and bioactive components are separated from the native tissue, limiting the regenerative potential of the design. Additionally, these interactions prevent desired tissue integration and angiogenesis, preventing functionality of the design. Recent evidence supports that mesenchymal stem cells (MSC) and hematopoietic stem cells (HSC) can have beneficial effects which alter the inflammatory responses and improve healing. The purpose of this study was to examine whether stem cells could be targeted to the site of biomaterial implantation and whether increasing local stem cell responses could improve the tissue response to PLGA scaffold implants. Through incorporation of SDF-1α through factor adsorption and mini-osmotic pump delivery, the host-derived stem cell response can be improved resulting in 3X increase in stem cell populations at the interface for up to 2 weeks. These interactions were found to significantly alter the acute mast cell responses, reducing the number of mast cells and degranulated mast cells near the scaffold implants. This led to subsequent downstream reduction in the inflammatory cell responses, and through altered mast cell activation and stem cell participation, increased angiogenesis and decreased fibrotic responses to the scaffold implants. These results support that enhanced recruitment of autologous stem cells can improve the tissue responses to biomaterial implants through modifying/bypassing inflammatory cell responses and jumpstarting stem cell participation in healing at the implant interface. PMID:20185171

STAT3 signaling pathway is necessary for cell survival and tumorsphere forming capacity in ALDH{sup +}/CD133{sup +} stem cell-like human colon cancer cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lin, Li, E-mail: lin.796@osu.edu; Division of Cardiology, Department of Internal Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030; Fuchs, James

2011-12-16

Highlights: Black-Right-Pointing-Pointer The phosphorylated or activated form of STAT3 was expressed in colon cancer stem-like cells. Black-Right-Pointing-Pointer STAT3 inhibitor, FLLL32 inhibits P-STAT3 and STAT3 target genes in colon cancer stem-like cells. Black-Right-Pointing-Pointer Inhibition of STAT3 resulted in decreased cell viability and reduced numbers of tumorspheres. Black-Right-Pointing-Pointer STAT3 is required for survival and tumorsphere forming capacity in colon cancer stem-like cells. Black-Right-Pointing-Pointer Targeting STAT3 in cancer stem-like cells may offer a novel treatment approach for colon cancer. -- Abstract: Persistent activation of Signal Transducers and Activators of Transcription 3 (STAT3) is frequently detected in colon cancer. Increasing evidence suggests the existencemore » of a small population of colon cancer stem or cancer-initiating cells may be responsible for tumor initiation, metastasis, and resistance to chemotherapy and radiation. Whether STAT3 plays a role in colon cancer-initiating cells and the effect of STAT3 inhibition is still unknown. Flow cytometry was used to isolate colon cancer stem-like cells from three independent human colon cancer cell lines characterized by both aldehyde dehydrogenase (ALDH)-positive and CD133-positive subpopulation (ALDH{sup +}/CD133{sup +}). The effects of STAT3 inhibition in colon cancer stem-like cells were examined. The phosphorylated or activated form of STAT3 was expressed in colon cancer stem-like cells and was reduced by a STAT3-selective small molecular inhibitor, FLLL32. FLLL32 also inhibited the expression of potential STAT3 downstream target genes in colon cancer stem-like cells including survivin, Bcl-XL, as well as Notch-1, -3, and -4, which may be involved in stem cell function. Furthermore, FLLL32 inhibited cell viability and tumorsphere formation as well as induced cleaved caspase-3 in colon cancer stem-like cells. FLLL32 is more potent than curcumin as evidenced with lower IC50 in colon cancer stem-like cells. In summary, our results indicate that STAT3 is a novel therapeutic target in colon cancer stem-like cells and inhibition of STAT3 in cancer stem-like cells may offer a potential treatment for colorectal cancer.« less

Parthenogenesis-derived Multipotent Stem Cells Adapted for Tissue Engineering Applications

PubMed Central

Koh, Chester J.; Delo, Dawn M.; Lee, Jang Won; Siddiqui, M. Minhaj; Lanza, Robert P.; Soker, Shay; Yoo, James J.; Atala, Anthony

2009-01-01

Embryonic stem cells are envisioned as a viable source of pluripotent cells for use in regenerative medicine applications when donor tissue is not available. However, most current harvest techniques for embryonic stem cells require the destruction of embryos, which has led to significant political and ethical limitations on their usage. Parthenogenesis, the process by which an egg can develop into an embryo in the absence of sperm, may be a potential source of embryonic stem cells that may avoid some of the political and ethical concerns surrounding embryonic stem cells. Here we provide the technical aspects of embryonic stem cell isolation and expansion from the parthenogenetic activation of oocytes. These cells were characterized for their stem-cell properties. In addition, these cells were induced to differentiate to the myogenic, osteogenic, adipogenic, and endothelial lineages, and were able to form muscle-like and bony-like tissue in vivo. Furthermore, parthenogenetic stem cells were able to integrate into injured muscle tissue. Together, these results demonstrate that parthenogenetic stem cells can be successfully isolated and utilized for various tissue engineering applications. PMID:18799133

The Evolution of the Stem Cell Theory for Heart Failure.

PubMed

Silvestre, Jean-Sébastien; Menasché, Philippe

2015-12-01

Various stem cell-based approaches for cardiac repair have achieved encouraging results in animal experiments, often leading to their rapid proceeding to clinical testing. However, freewheeling evolutionary developments of the stem cell theory might lead to dystopian scenarios where heterogeneous sources of therapeutic cells could promote mixed clinical outcomes in un-stratified patient populations. This review focuses on the lessons that should be learnt from the first generation of stem cell-based strategies and emphasizes the absolute requirement to better understand the basic mechanisms of stem cell biology and cardiogenesis. We will also discuss about the unexpected "big bang" in the stem cell theory, "blasting" the therapeutic cells to their unchallenged ability to release paracrine factors such as extracellular membrane vesicles. Paradoxically, the natural evolution of the stem cell theory for cardiac regeneration may end with the development of cell-free strategies with multiple cellular targets including cardiomyocytes but also other infiltrating or resident cardiac cells.

Mesenchymal Stem Cell-Mediated Functional Tooth Regeneration in Swine

PubMed Central

Fang, Dianji; Yamaza, Takayoshi; Seo, Byoung-Moo; Zhang, Chunmei; Liu, He; Gronthos, Stan; Wang, Cun-Yu; Shi, Songtao; Wang, Songlin

2006-01-01

Mesenchymal stem cell-mediated tissue regeneration is a promising approach for regenerative medicine for a wide range of applications. Here we report a new population of stem cells isolated from the root apical papilla of human teeth (SCAP, stem cells from apical papilla). Using a minipig model, we transplanted both human SCAP and periodontal ligament stem cells (PDLSCs) to generate a root/periodontal complex capable of supporting a porcelain crown, resulting in normal tooth function. This work integrates a stem cell-mediated tissue regeneration strategy, engineered materials for structure, and current dental crown technologies. This hybridized tissue engineering approach led to recovery of tooth strength and appearance. PMID:17183711

Influence of exercise and aging on extracellular matrix composition in the skeletal muscle stem cell niche.

PubMed

Garg, Koyal; Boppart, Marni D

2016-11-01

Skeletal muscle is endowed with a remarkable capacity for regeneration, primarily due to the reserve pool of muscle resident satellite cells. The satellite cell is the physiologically quiescent muscle stem cell that resides beneath the basal lamina and adjacent to the sarcolemma. The anatomic location of satellite cells is in close proximity to vasculature where they interact with other muscle resident stem/stromal cells (e.g., mesenchymal stem cells and pericytes) through paracrine mechanisms. This mini-review describes the components of the muscle stem cell niche, as well as the influence of exercise and aging on the muscle stem cell niche. Although exercise promotes ECM reorganization and stem cell accumulation, aging is associated with dense ECM deposition and loss of stem cell function resulting in reduced regenerative capacity and strength. An improved understanding of the niche elements will be valuable to inform the development of therapeutic interventions aimed at improving skeletal muscle regeneration and adaptation over the life span. Copyright © 2016 the American Physiological Society.

Incorporation of Biomaterials in Multicellular Aggregates Modulates Pluripotent Stem Cell Differentiation

PubMed Central

Bratt-Leal, Andrés M.; Carpenedo, Richard L.; Ungrin, Mark; Zandstra, Peter W.; McDevitt, Todd C.

2010-01-01

Biomaterials are increasingly being used to engineer the biochemical and biophysical properties of the extracellular stem cell microenvironment in order to tailor niche characteristics and direct cell phenotype. To date, stem cell-biomaterial interactions have largely been studied by introducing stem cells into artificial environments, such as 2D cell culture on biomaterial surfaces, encapsulation of cell suspensions within hydrogel materials, or cell seeding on 3D polymeric scaffolds. In this study, microparticles fabricated from different materials, such as agarose, PLGA and gelatin, were stably integrated, in a dose-dependent manner, within aggregates of pluripotent stem cells (PSCs) prior to differentiation as a means to directly examine stem cell-biomaterial interactions in 3D. Interestingly, the presence of the materials within the stem cell aggregates differentially modulated the gene and protein expression patterns of several differentiation markers without adversely affecting cell viability. Microparticle incorporation within 3D stem cell aggregates can control the spatial presentation of extracellular environmental cues (i.e. soluble factors, extracellular matrix and intercellular adhesion molecules) as a means to direct the differentiation of stem cells for tissue engineering and regenerative medicine applications. In addition, these results suggest that the physical presence of microparticles within stem cell aggregates does not compromise PSC differentiation, but in fact the choice of biomaterials can impact the propensity of stem cells to adopt particular differentiated cell phenotypes. PMID:20864164

Mobilization of Hematopoietic Stem and Progenitor Cells Using Inhibitors of CXCR4 and VLA-4

PubMed Central

Rettig, Michael P.; Ansstas, George; DiPersio, John F.

2012-01-01

Successful hematopoietic stem cell transplant (HSCT) requires the infusion of a sufficient number of hematopoietic stem/progenitor cells (HSPCs) that are capable of homing to the bone marrow cavity and regenerating durable trilineage hematopoiesis in a timely fashion. Stem cells harvested from peripheral blood are the most commonly used graft source in HSCT. While granulocyte colony-stimulating factor (G-CSF) is the most frequently used agent for stem cell mobilization, the use of G-CSF alone results in suboptimal stem cell yields in a significant proportion of patients. Both the chemokine receptor CXCR4 and the integrin α4β1 (VLA-4) play important roles in the homing and retention of HSPCs within the bone marrow microenvironment. Preclinical and/or clinical studies have shown that targeted disruption of the interaction of CXCR4 or VLA-4 with their ligands results in the rapid and reversible mobilization of hematopoietic stem cells into the peripheral circulation and is synergistic when combined with G-CSF. In this review we discuss the development of small molecule CXCR4 and VLA-4 inhibitors and how they may improve the utility and convenience of peripheral blood stem cell transplantation. PMID:21886173

Tissue damage-induced intestinal stem cell division in Drosophila

PubMed Central

Amcheslavsky, Alla; Jiang, Jin; Ip, Y. Tony

2009-01-01

SUMMARY Stem cell division is essential for tissue integrity during growth, aging, and pathogenic assaults. Adult gastrointestinal tract encounters numerous stimulations and impaired tissue regeneration may lead to inflammatory diseases and cancer. Intestinal stem cells in adult Drosophila have recently been identified and shown to replenish the various cell types within the midgut. However, it is not known whether these intestinal stem cells can respond to environmental challenges. By feeding dextran sulfate sodium and bleomycin to flies and by expressing apoptotic proteins, we show that Drosophila intestinal stem cells can increase the rate of division in response to tissue damage. Moreover, if tissue damage results in epithelial cell loss, the newly formed enteroblasts can differentiate into mature epithelial cells. By using this newly established system of intestinal stem cell proliferation and tissue regeneration, we find that the insulin receptor signaling pathway is required for intestinal stem cell division. PMID:19128792

Role of bioinspired polymers in determination of pluripotent stem cell fate

PubMed Central

Abraham, Sheena; Eroshenko, Nikolai; Rao, Raj R

2009-01-01

Human pluripotent stem cells, including embryonic and induced pluripotent stem cells, hold enormous potential for the treatment of many diseases, owing to their ability to generate cell types useful for therapeutic applications. Currently, many stem cell culture propagation and differentiation systems incorporate animal-derived components for promoting self-renewal and differentiation. However, use of these components is labor intensive, carries the risk of xenogeneic contamination and yields compromised experimental results that are difficult to duplicate. From a biomaterials perspective, the generation of an animal- and cell-free biomimetic microenvironment that provides the appropriate physical and chemical cues for stem cell self-renewal or differentiation into specialized cell types would be ideal. This review presents the use of natural and synthetic polymers that support propagation and differentiation of stem cells, in an attempt to obtain a clear understanding of the factors responsible for the determination of stem cell fate. PMID:19580405

Orphan nuclear receptor TLX activates Wnt/β-catenin signalling to stimulate neural stem cell proliferation and self-renewal

PubMed Central

Qu, Qiuhao; Sun, Guoqiang; Li, Wenwu; Yang, Su; Ye, Peng; Zhao, Chunnian; Yu, Ruth T.; Gage, Fred H.; Evans, Ronald M.; Shi, Yanhong

2010-01-01

The nuclear receptor TLX (also known as NR2E1) is essential for adult neural stem cell self-renewal; however, the molecular mechanisms involved remain elusive. Here we show that TLX activates the canonical Wnt/β-catenin pathway in adult mouse neural stem cells. Furthermore, we demonstrate that Wnt/β-catenin signalling is important in the proliferation and self-renewal of adult neural stem cells in the presence of epidermal growth factor and fibroblast growth factor. Wnt7a and active β-catenin promote neural stem cell self-renewal, whereas the deletion of Wnt7a or the lentiviral transduction of axin, a β-catenin inhibitor, led to decreased cell proliferation in adult neurogenic areas. Lentiviral transduction of active β-catenin led to increased numbers of type B neural stem cells in the subventricular zone of adult brains, whereas deletion of Wnt7a or TLX resulted in decreased numbers of neural stem cells retaining bromodeoxyuridine label in the adult brain. Both Wnt7a and active β-catenin significantly rescued a TLX (also known as Nr2e1) short interfering RNA-induced deficiency in neural stem cell proliferation. Lentiviral transduction of an active β-catenin increased cell proliferation in neurogenic areas of TLX-null adult brains markedly. These results strongly support the hypothesis that TLX acts through the Wnt/β-catenin pathway to regulate neural stem cell proliferation and self-renewal. Moreover, this study suggests that neural stem cells can promote their own self-renewal by secreting signalling molecules that act in an autocrine/paracrine mode. PMID:20010817

Orphan nuclear receptor TLX activates Wnt/beta-catenin signalling to stimulate neural stem cell proliferation and self-renewal.

PubMed

Qu, Qiuhao; Sun, Guoqiang; Li, Wenwu; Yang, Su; Ye, Peng; Zhao, Chunnian; Yu, Ruth T; Gage, Fred H; Evans, Ronald M; Shi, Yanhong

2010-01-01

The nuclear receptor TLX (also known as NR2E1) is essential for adult neural stem cell self-renewal; however, the molecular mechanisms involved remain elusive. Here we show that TLX activates the canonical Wnt/beta-catenin pathway in adult mouse neural stem cells. Furthermore, we demonstrate that Wnt/beta-catenin signalling is important in the proliferation and self-renewal of adult neural stem cells in the presence of epidermal growth factor and fibroblast growth factor. Wnt7a and active beta-catenin promote neural stem cell self-renewal, whereas the deletion of Wnt7a or the lentiviral transduction of axin, a beta-catenin inhibitor, led to decreased cell proliferation in adult neurogenic areas. Lentiviral transduction of active beta-catenin led to increased numbers of type B neural stem cells in the subventricular zone of adult brains, whereas deletion of Wnt7a or TLX resulted in decreased numbers of neural stem cells retaining bromodeoxyuridine label in the adult brain. Both Wnt7a and active beta-catenin significantly rescued a TLX (also known as Nr2e1) short interfering RNA-induced deficiency in neural stem cell proliferation. Lentiviral transduction of an active beta-catenin increased cell proliferation in neurogenic areas of TLX-null adult brains markedly. These results strongly support the hypothesis that TLX acts through the Wnt/beta-catenin pathway to regulate neural stem cell proliferation and self-renewal. Moreover, this study suggests that neural stem cells can promote their own self-renewal by secreting signalling molecules that act in an autocrine/paracrine mode.

Electroactive 3D materials for cardiac tissue engineering

NASA Astrophysics Data System (ADS)

Gelmi, Amy; Zhang, Jiabin; Cieslar-Pobuda, Artur; Ljunngren, Monika K.; Los, Marek Jan; Rafat, Mehrdad; Jager, Edwin W. H.

2015-04-01

By-pass surgery and heart transplantation are traditionally used to restore the heart's functionality after a myocardial Infarction (MI or heart attack) that results in scar tissue formation and impaired cardiac function. However, both procedures are associated with serious post-surgical complications. Therefore, new strategies to help re-establish heart functionality are necessary. Tissue engineering and stem cell therapy are the promising approaches that are being explored for the treatment of MI. The stem cell niche is extremely important for the proliferation and differentiation of stem cells and tissue regeneration. For the introduction of stem cells into the host tissue an artificial carrier such as a scaffold is preferred as direct injection of stem cells has resulted in fast stem cell death. Such scaffold will provide the proper microenvironment that can be altered electronically to provide temporal stimulation to the cells. We have developed an electroactive polymer (EAP) scaffold for cardiac tissue engineering. The EAP scaffold mimics the extracellular matrix and provides a 3D microenvironment that can be easily tuned during fabrication, such as controllable fibre dimensions, alignment, and coating. In addition, the scaffold can provide electrical and electromechanical stimulation to the stem cells which are important external stimuli to stem cell differentiation. We tested the initial biocompatibility of these scaffolds using cardiac progenitor cells (CPCs), and continued onto more sensitive induced pluripotent stem cells (iPS). We present the fabrication and characterisation of these electroactive fibres as well as the response of increasingly sensitive cell types to the scaffolds.

FSH-FSHR3-stem cells in ovary surface epithelium: basis for adult ovarian biology, failure, aging, and cancer.

PubMed

Bhartiya, Deepa; Singh, Jarnail

2015-01-01

Despite extensive research, genetic basis of premature ovarian failure (POF) and ovarian cancer still remains elusive. It is indeed paradoxical that scientists searched for mutations in FSH receptor (FSHR) expressed on granulosa cells, whereas more than 90% of cancers arise in ovary surface epithelium (OSE). Two distinct populations of stem cells including very small embryonic-like stem cells (VSELs) and ovarian stem cells (OSCs) exist in OSE, are responsible for neo-oogenesis and primordial follicle assembly in adult life, and are modulated by FSH via its alternatively spliced receptor variant FSHR3 (growth factor type 1 receptor acting via calcium signaling and the ERK/MAPK pathway). Any defect in FSH-FSHR3-stem cell interaction in OSE may affect folliculogenesis and thus result in POF. Ovarian aging is associated with a compromised microenvironment that does not support stem cell differentiation into oocytes and further folliculogenesis. FSH exerts a mitogenic effect on OSE and elevated FSH levels associated with advanced age may provide a continuous trigger for stem cells to proliferate resulting in cancer, thus supporting gonadotropin theory for ovarian cancer. Present review is an attempt to put adult ovarian biology, POF, aging, and cancer in the perspective of FSH-FSHR3-stem cell network that functions in OSE. This hypothesis is further supported by the recent understanding that: i) cancer is a stem cell disease and OSE is the niche for ovarian cancer stem cells; ii) ovarian OCT4-positive stem cells are regulated by FSH; and iii) OCT4 along with LIN28 and BMP4 are highly expressed in ovarian cancers. © 2015 Society for Reproduction and Fertility.

Stem cell-associated genes are extremely poor prognostic factors for soft-tissue sarcoma patients.

PubMed

Taubert, H; Würl, P; Greither, T; Kappler, M; Bache, M; Bartel, F; Kehlen, A; Lautenschläger, C; Harris, L C; Kaushal, D; Füssel, S; Meye, A; Böhnke, A; Schmidt, H; Holzhausen, H-J; Hauptmann, S

2007-11-01

Cancer stem cells can play an important role in tumorigenesis and tumor progression. However, it is still difficult to detect and isolate cancer stem cells. An alternative approach is to analyse stem cell-associated gene expression. We investigated the coexpression of three stem cell-associated genes, Hiwi, hTERT and survivin, by quantitative real-time-PCR in 104 primary soft-tissue sarcomas (STS). Multivariate Cox's proportional hazards regression analyses allowed correlating gene expression with overall survival for STS patients. Coexpression of all three stem cell-associated genes resulted in a significantly increased risk of tumor-related death. Importantly, tumors of patients with the poorest prognosis were of all four tumor stages, suggesting that their risk is based upon coexpression of stem cell-associated genes rather than on tumor stage.

Development of tyrosinase-based reporter genes for preclinical photoacoustic imaging of mesenchymal stem cells

NASA Astrophysics Data System (ADS)

Märk, Julia; Ruschke, Karen; Dortay, Hakan; Schreiber, Isabelle; Sass, Andrea; Qazi, Taimoor; Pumberger, Matthias; Laufer, Jan

2014-03-01

The capability to image stem cells in vivo in small animal models over extended periods of time is important to furthering our understanding of the processes involved in tissue regeneration. Photoacoustic imaging is suited to this application as it can provide high resolution (tens of microns) absorption-based images of superficial tissues (cm depths). However, stem cells are rare, highly migratory, and can divide into more specialised cells. Genetic labelling strategies are therefore advantageous for their visualisation. In this study, methods for the transfection and viral transduction of mesenchymal stem cells with reporter genes for the co-expression of tyrosinase and a fluorescent protein (mCherry). Initial photoacoustic imaging experiments of tyrosinase expressing cells in small animal models of tissue regeneration were also conducted. Lentiviral transduction methods were shown to result in stable expression of tyrosinase and mCherry in mesenchymal stem cells. The results suggest that photoacoustic imaging using reporter genes is suitable for the study of stem cell driven tissue regeneration in small animals.

Tanshinone IIA inhibits cervix carcinoma stem cells migration and invasion via inhibiting YAP transcriptional activity.

PubMed

Qin, Jinghao; Shi, Hongbing; Xu, Yanjie; Zhao, Fang; Wang, Qing

2018-06-14

This study aims to explore the effects and related mechanisms of Tanshinone IIA in cervix carcinoma (CC) stemness-like cells migration, invasion, stemness and chemotherapeutical sensitivity. Here, we found that Tanshinone IIA suppressed CC stemness-like cells migration and invasion in a concentration- and time-dependent manner. And consistent results were obtained in CC cells stemness characterized as the decrease of CC stemness markers expression and cells spheroid formation ability. Mechanistically, we found that Tanshinone IIA suppressed RNA binding protein HuR translocation from nuclear to cytoplasm, and thus reduced YAP mRNAs stability and transcriptional activity. Importantly, overexpression YAP-5SA rescued the inhibition of Tanshinone IIA on CC cells stemness. Furthermore, Tanshinone IIA enhanced adriamycin sensitivity in CC stemness-like cells, this effect was attenuated by YAP-5SA overexpression too. Therefore, Tanshinone IIA could suppress CC stemness-like cells migration and invasion by inhibiting YAP transcriptional activity. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

Review article: stem cells in human reproduction.

PubMed

Gargett, Caroline E

2007-07-01

The derivation of human embryonic stem (hES) cells heralds a new era in stem cell research, generating excitement for their therapeutic potential in regenerative medicine. Pioneering work of embryologists, developmental biologists, and reproductive medicine practitioners in in vitro fertilization clinics has facilitated hES cell research. This review summarizes current research focused on optimizing hES cell culture conditions for good manufacturing practice, directing hES cell differentiation toward trophectoderm and germ cells, and approaches used to reprogram cells for pluripotent cell derivation. The identification of germ stem cells in the testis and the recent controversy over their existence in the ovary raise the possibility of harnessing them for treating young cancer survivors. There is also the potential to harvest fetal stem cells with pluripotent cell-like properties from discarded placental tissues. The recent identification of adult stem/progenitor cell activity in the human endometrium offers a new understanding of common gynecological diseases. Discoveries resulting from research into embryonic, germ, fetal, and adult stem cells are highly relevant to human reproduction.

The neural stem cell fate determinant TLX promotes tumorigenesis and genesis of cells resembling glioma stem cells.

PubMed

Park, Hyo-Jung; Kim, Jun-Kyum; Jeon, Hye-Min; Oh, Se-Yeong; Kim, Sung-Hak; Nam, Do-Hyun; Kim, Hyunggee

2010-11-01

A growing body of evidence indicates that deregulation of stem cell fate determinants is a hallmark of many types of malignancies. The neural stem cell fate determinant TLX plays a pivotal role in neurogenesis in the adult brain by maintaining neural stem cells. Here, we report a tumorigenic role of TLX in brain tumor initiation and progression. Increased TLX expression was observed in a number of glioma cells and glioma stem cells, and correlated with poor survival of patients with gliomas. Ectopic expression of TLX in the U87MG glioma cell line and Ink4a/Arf-deficient mouse astrocytes (Ink4a/Arf(-/-) astrocytes) induced cell proliferation with a concomitant increase in cyclin D expression, and accelerated foci formation in soft agar and tumor formation in in vivo transplantation assays. Furthermore, overexpression of TLX in Ink4a/Arf(-/-) astrocytes inhibited cell migration and invasion and promoted neurosphere formation and Nestin expression, which are hallmark characteristics of glioma stem cells, under stem cell culture conditions. Our results indicate that TLX is involved in glioma stem cell genesis and represents a potential therapeutic target for this type of malignancy.

Regulation and Function of TIFAB in Myelodysplastic Syndrome

DTIC Science & Technology

2014-08-01

knockdown of TIFAB in human CD34+ hematopoietic stem /progenitor cells results in increased survival and proliferation, TIFAB inhibits TRAF6 protein...regulator of human hematopoietic cells . Our key observations show that knockdown of TIFAB in human CD34+ hematopoietic stem /progenitor cells results in...reveals an essential role of mTOR in hematopoietic stem cell engraftment and hematopoiesis. (2013). Haematologica,!98(9):!135381358.! PMID:!23716557

Increased circulating stem cells and better cognitive performance in traumatic brain injury subjects following hyperbaric oxygen therapy.

PubMed

Shandley, Sabrina; Wolf, E George; Schubert-Kappan, Christine M; Baugh, Laura M; Richards, Michael F; Prye, Jennifer; Arizpe, Helen M; Kalns, John

2017-01-01

Traumatic brain injury (TBI) may cause persistent cognitive dysfunction. A pilot clinical study was performed to determine if hyperbaric oxygen (HBO₂) treatment improves cognitive performance. It was hypothesized that stem cells, mobilized by HBO₂ treatment, are recruited to repair damaged neuronal tissue. This hypothesis was tested by measuring the relative abundance of stem cells in peripheral blood and cognitive performance during this clinical trial. The subject population consisted of 28 subjects with persistent cognitive impairment caused by mild to moderate TBI suffered during military deployment to Iraq or Afghanistan. Fluorescence-activated cell sorting (FACS) analysis was performed for stem cell markers in peripheral blood and correlated with variables resulting from standard tests of cognitive performance and post-traumatic stress disorder: ImPACT, BrainCheckers and PCL-M test results. HBO₂ treatment correlated with stem cell mobilization as well as increased cognitive performance. Together these results support the hypothesis that stem cell mobilization may be required for cognitive improvement in this population. Copyright© Undersea and Hyperbaric Medical Society.

The human stem cell hierarchy is defined by a functional dependence on Mcl-1 for self-renewal capacity.

PubMed

Campbell, Clinton J V; Lee, Jung Bok; Levadoux-Martin, Marilyne; Wynder, Tracy; Xenocostas, Anargyros; Leber, Brian; Bhatia, Mickie

2010-09-02

The molecular basis for the unique proliferative and self-renewal properties that hierarchically distinguish human stem cells from progenitors and terminally differentiated cells remains largely unknown. We report a role for the Bcl-2 family member myeloid cell leukemia-1 (Mcl-1) as an indispensable regulator of self-renewal in human stem cells and show that a functional dependence on Mcl-1 defines the human stem cell hierarchy. In vivo pharmacologic targeting of the Bcl-2 family members in human hematopoietic stem cells (HSCs) and human leukemic stem cells reduced stem cell regenerative and self-renewal function. Subsequent protein expression studies showed that, among the Bcl-2 family members, only Mcl-1 was up-regulated exclusively in the human HSC fraction on in vivo regeneration of hematopoiesis. Short hairpin RNA-knockdown of Mcl-1 in human cord blood cells did not affect survival in the HSC or hematopoietic progenitor cell fractions in vitro but specifically reduced the in vivo self-renewal function of human HSCs. Moreover, knockdown of Mcl-1 in ontogenetically primitive human pluripotent stem cells resulted in almost complete ablation of stem cell self-renewal function. Our findings show that Mcl-1 is an essential regulator of stem cell self-renewal in humans and therefore represents an axis for therapeutic interventions.

miR-21 promotes the differentiation of hair follicle-derived neural crest stem cells into Schwann cells

PubMed Central

Ni, Yuxin; Zhang, Kaizhi; Liu, Xuejuan; Yang, Tingting; Wang, Baixiang; Fu, Li; A, Lan; Zhou, Yanmin

2014-01-01

Hair follicle-derived neural crest stem cells can be induced to differentiate into Schwann cells in vivo and in vitro. However, the underlying regulatory mechanism during cell differentiation remains poorly understood. This study isolated neural crest stem cells from human hair follicles and induced them to differentiate into Schwann cells. Quantitative RT-PCR showed that microRNA (miR)-21 expression was gradually increased during the differentiation of neural crest stem cells into Schwann cells. After transfection with the miR-21 agonist (agomir-21), the differentiation capacity of neural crest stem cells was enhanced. By contrast, after transfection with the miR-21 antagonist (antagomir-21), the differentiation capacity was attenuated. Further study results showed that SOX-2 was an effective target of miR-21. Without compromising SOX2 mRNA expression, miR-21 can down-regulate SOX protein expression by binding to the 3′-UTR of miR-21 mRNA. Knocking out the SOX2 gene from the neural crest stem cells significantly reversed the antagomir-21 inhibition of neural crest stem cells differentiating into Schwann cells. The results suggest that miR-21 expression was increased during the differentiation of neural crest stem cells into Schwann cells and miR-21 promoted the differentiation through down-regulating SOX protein expression by binding to the 3′-UTR of SOX2 mRNA. PMID:25206896

Fraudsters operate and officialdom turns a blind eye: a proposal for controlling stem cell therapy in China.

PubMed

Jiang, Li; Dong, Bing He

2016-09-01

Stem cell tourism-the flow of patients from home countries to destination countries to obtain stem cell treatment-is a growing business in China. Many concerns have been raised regarding fraudsters that operate unsafe stem cell therapies and an officialdom that turns a blind eye to the questionable technology. The Chinese regulatory approach to stem cell research is based on Guidelines and Administrative Measures, rather than legislation, and may have no binding force on certain institutions, such as military hospitals. There is no liability and traceability system and no visible set of penalties for non-compliance in the stem cell legal framework. In addition to the lack of safety and efficacy systems in the regulations, no specific expert authority has been established to monitor stem cell therapy to date. Recognizing the global nature of stem cell tourism, this article argues that resolving stem cell tourism issues may require not only the Chinese government but also an international mechanism for transparency and ethical oversight. A stringent set of international regulations that govern stem cell therapies can encourage China to improve stem cell regulation and enforcement to fulfill its obligations. Through an international consensus, a minimum standard for clinical stem cell research and a central enforcement system will be provided. As a result, rogue clinics that conduct unauthorized stem cell therapies can be penalized, and countries that are reluctant to implement the reconciled regulations should be sanctioned.

Ablation of proliferating neural stem cells during early life is sufficient to reduce adult hippocampal neurogenesis.

PubMed

Youssef, Mary; Krish, Varsha S; Kirshenbaum, Greer S; Atsak, Piray; Lass, Tamara J; Lieberman, Sophie R; Leonardo, E David; Dranovsky, Alex

2018-05-09

Environmental exposures during early life, but not during adolescence or adulthood, lead to persistent reductions in neurogenesis in the adult hippocampal dentate gyrus (DG). The mechanisms by which early life exposures lead to long-term deficits in neurogenesis remain unclear. Here, we investigated whether targeted ablation of dividing neural stem cells during early life is sufficient to produce long-term decreases in DG neurogenesis. Having previously found that the stem cell lineage is resistant to long-term effects of transient ablation of dividing stem cells during adolescence or adulthood (Kirshenbaum et al., 2014), we used a similar pharmacogenetic approach to target dividing neural stem cells for elimination during early life periods sensitive to environmental insults. We then assessed the Nestin stem cell lineage in adulthood. We found that the adult neural stem cell reservoir was depleted following ablation during the first postnatal week, when stem cells were highly proliferative, but not during the third postnatal week, when stem cells were more quiescent. Remarkably, ablating proliferating stem cells during either the first or third postnatal week led to reduced adult neurogenesis out of proportion to the changes in the stem cell pool, indicating a disruption of the stem cell function or niche following stem cell ablation in early life. These results highlight the first three postnatal weeks as a series of sensitive periods during which elimination of dividing stem cells leads to lasting alterations in adult DG neurogenesis and stem cell function. These findings contribute to our understanding of the relationship between DG development and adult neurogenesis, as well as suggest a possible mechanism by which early life experiences may lead to lasting deficits in adult hippocampal neurogenesis. This article is protected by copyright. All rights reserved. © 2018 Wiley Periodicals, Inc.

Effect of Dedifferentiation on Time to Mutation Acquisition in Stem Cell-Driven Cancers

PubMed Central

Jilkine, Alexandra; Gutenkunst, Ryan N.

2014-01-01

Accumulating evidence suggests that many tumors have a hierarchical organization, with the bulk of the tumor composed of relatively differentiated short-lived progenitor cells that are maintained by a small population of undifferentiated long-lived cancer stem cells. It is unclear, however, whether cancer stem cells originate from normal stem cells or from dedifferentiated progenitor cells. To address this, we mathematically modeled the effect of dedifferentiation on carcinogenesis. We considered a hybrid stochastic-deterministic model of mutation accumulation in both stem cells and progenitors, including dedifferentiation of progenitor cells to a stem cell-like state. We performed exact computer simulations of the emergence of tumor subpopulations with two mutations, and we derived semi-analytical estimates for the waiting time distribution to fixation. Our results suggest that dedifferentiation may play an important role in carcinogenesis, depending on how stem cell homeostasis is maintained. If the stem cell population size is held strictly constant (due to all divisions being asymmetric), we found that dedifferentiation acts like a positive selective force in the stem cell population and thus speeds carcinogenesis. If the stem cell population size is allowed to vary stochastically with density-dependent reproduction rates (allowing both symmetric and asymmetric divisions), we found that dedifferentiation beyond a critical threshold leads to exponential growth of the stem cell population. Thus, dedifferentiation may play a crucial role, the common modeling assumption of constant stem cell population size may not be adequate, and further progress in understanding carcinogenesis demands a more detailed mechanistic understanding of stem cell homeostasis. PMID:24603301

Knowledge and Attitude about Stem Cells and Their Application in Medicine among Nursing Students in Universiti Sains Malaysia, Malaysia

PubMed Central

LYE, Jee Leng; SOON, Lean Keng; WAN AHMAD, Wan Amir Nizam; TAN, Suat Cheng

2015-01-01

Background: Stem cell research has been extensively explored worldwide to enhance human health in medical setting. Nevertheless, there is currently no full understanding of the stem cell knowledge and attitude levels among student nurses in Malaysia. This study aimed to assess the level of stem cell knowledge, attitude toward stem cell application in medicine, and its association with years of education, among Universiti Sains Malaysia (USM) undergraduate nursing students. Methods: A cross-sectional study (n = 88) was conducted using self-administered questionnaire consisted of demographic information, stem cells knowledge and attitude statements. Data was analysed using Statistical Package Social Software 20.0. Results: The majority of participants (92%) had moderate knowledge score about stem cells. Many students (33%) worried that stem cell application might cause a harm to humanity yet had a positive (76.1%) attitude towards its therapeutic potential (45.5%). Poor correlation between knowledge and attitude (r = 0.08) indicated that acceptance towards stem cell is not solely based on the knowledge level but also on other factors including religion and culture. Conclusion: Therefore, this study suggests that various educational programs on stem cell should be implemented considering the religion, cultural, social, and behavioural determinants in the population to improve stem cell knowledge and encourage a more positive attitude towards stem cells in medicine among these nursing students. PMID:26715905

Stem cells are dispensable for lung homeostasis but restore airways after injury.

PubMed

Giangreco, Adam; Arwert, Esther N; Rosewell, Ian R; Snyder, Joshua; Watt, Fiona M; Stripp, Barry R

2009-06-09

Local tissue stem cells have been described in airways of the lung but their contribution to normal epithelial maintenance is currently unknown. We therefore developed aggregation chimera mice and a whole-lung imaging method to determine the relative contributions of progenitor (Clara) and bronchiolar stem cells to epithelial maintenance and repair. In normal and moderately injured airways chimeric patches were small in size and not associated with previously described stem cell niches. This finding suggested that single, randomly distributed progenitor cells maintain normal epithelial homeostasis. In contrast we found that repair following severe lung injury resulted in the generation of rare, large clonal cell patches that were associated with stem cell niches. This study provides evidence that epithelial stem cells are dispensable for normal airway homeostasis. We also demonstrate that stem cell activation and robust clonal cellular expansion occur only during repair from severe lung injury.

Genetic modification of hematopoietic stem cells: recent advances in the gene therapy of inherited diseases.

PubMed

Bueren, Juan A; Guenechea, Guillermo; Casado, José A; Lamana, María Luisa; Segovia, José C

2003-01-01

Hematopoietic stem cells constitute a rare population of precursor cells with remarkable properties for being used as targets in gene therapy protocols. The last years have been particularly productive both in the fields of gene therapy and stem cell biology. Results from ongoing clinical trials have shown the first unquestionable clinical benefits of immunodeficient patients transplanted with genetically modified autologous stem cells. On the other hand, severe side effects in a few patients treated with gene therapy have also been reported, indicating the usefulness of further improving the vectors currently used in gene therapy clinical trials. In the field of stem cell biology, evidence showing the plastic potential of adult hematopoietic stem cells and data indicating the multipotency of adult mesenchymal precursor cells have been presented. Also, the generation of embryonic stem cells by means of nuclear transfer techniques has appeared as a new methodology with direct implications in gene therapy.

Canonical Wnt Signaling as a Specific Marker of Normal and Tumorigenic Mammary Stem Cells

DTIC Science & Technology

2010-02-01

for mammary stem cells and be a target for transformation that results in the formation of aggressive mammary tumors. Breast cancer stem cells, Wnt...tumorigenesis, and human breast cancer. In addition, increasing evidence suggests that tumors arise from either normal stem or progenitor cells...population of mammary tumor cells that are CD24+/CD49++. Since Wnt pathway activation occurs in human breast cancer and is required for

Combining targeted drugs to overcome and prevent resistance of solid cancers with some stem-like cell features

PubMed Central

Koivunen, Peppi; Koivunen, Jussi P.

2014-01-01

Treatment resistance significantly inhibits the efficiency of targeted cancer therapies in drug-sensitive genotypes. In the current work, we studied mechanisms for rapidly occurring, adaptive resistance in targeted therapy-sensitive lung, breast, and melanoma cancer cell lines. The results show that in ALK translocated lung cancer lines H3122 and H2228, cells with cancer stem-like cell features characterized by high expression of cancer stem cell markers and/or in vivo tumorigenesis can mediate adaptive resistance to oncogene ablative therapy. When pharmacological ablation of ALK oncogene was accompanied with PI3K inhibitor or salinomycin therapy, cancer stem-like cell features were reversed which was accompanied with decreased colony formation. Furthermore, co-targeting was able to block the formation of acquired resistance in H3122 line. The results suggest that cells with cancer stem-like cell features can mediate adaptive resistance to targeted therapies. Since these cells follow the stochastic model, concurrent therapy with an oncogene ablating agent and a stem-like cell-targeting drug is needed for maximal therapeutic efficiency. PMID:25238228

Human adipose-derived stem cells promote vascularization of collagen-based scaffolds transplanted into nude mice

PubMed Central

Cherubino, Mario; Valdatta, Luigi; Balzaretti, Riccardo; Pellegatta, Igor; Rossi, Federica; Protasoni, Marina; Tedeschi, Alessandra; Accolla, Roberto S; Bernardini, Giovanni; Gornati, Rosalba

2016-01-01

Aim: After in vivo implantation of cell-loaded devices, only the cells close to the capillaries can obtain nutrients to maintain their functions. It is known that factors secreted by stem cells, rather than stem cells themselves, are fundamental to guarantee new vascularization in the area of implant. Materials & methods: To investigate this possibility, we have grafted mice with Bilayer and Flowable Integra® scaffolds, loaded or not with human adipose-derived stem cells. Results: Our results support the therapeutic potential of human adipose-derived stem cells to induce new vascular networks of engineered organs and tissues. Conclusion: This finding suggests that our approach can help to form new vascular networks that allow sufficient vascularization of engineered organs and tissues in cases of difficult wound healing due to ischemic conditions. PMID:26965659

Radiobiological characteristics of cancer stem cells from esophageal cancer cell lines

PubMed Central

Wang, Jian-Lin; Yu, Jing-Ping; Sun, Zhi-Qiang; Sun, Su-Ping

2014-01-01

AIM: To study the cancer stem cell population in esophageal cancer cell lines KYSE-150 and TE-1 and identify whether the resulting stem-like spheroid cells display cancer stem cells and radiation resistance characteristics. METHODS: A serum-free medium (SFM) suspension was used to culture esophageal cancer stem cell lines and enrich the esophageal stem-like spheres. A reverse transcription polymerase chain reaction assay was used to detect stem cell gene expression in the spheroid cells. Radiosensitivity of stem-like spheres and parental cells were evaluated by clonogenic assays. Furthermore, different cells after different doses of irradiation were tested to evaluate the change in sphere formation, cell cycle and CD44+CD271+ expression of tumor stem-like spheroid cells using flow cytometry before and after irradiation. RESULTS: The cells were observed to generate an increased number of spheres in SFM with increasing cell passage. Radiation increased the rate of generation of stem-like spheres in both types of cells. The average survival fraction (SF2) of the cultured KYSE-150 compared with TE-1 stem-like spheres after 2 Gy of radiation was 0.81 ± 0.03 vs 0.87 ± 0.01 (P < 0.05), while the average SF2 of KYSE-150 compared with TE-1 parental cells was 0.69 ± 0.04 vs 0.80 ± 0.03, P < 0.05. In the esophageal parental cells, irradiation dose-dependently induced G2 arrest. Stem-like esophageal spheres were resistant to irradiation-induced G2 arrest without significant changes in the percentage population of irradiated stem-like cells. Under irradiation at 0, 4, and 8 Gy, the CD44+CD271+ cell percentage for KYSE150 parental cells was 1.08% ± 0.03% vs 1.29% ± 0.07% vs 1.11% ± 0.09%, respectively; the CD44+CD271+ cell percentage for TE1 parental cells was 1.16% ± 0.11% vs 0.97% ± 0.08% vs 1.45% ± 0.35%, respectively. The differences were not statistically significant. Under irradiation at 0, 4, and 8 Gy, the CD44+CD271+ cell percentage for KYSE-150 stem-like spheres was 35.83% ± 1.23% vs 44.9% ± 1.67% vs 57.77% ± 1.88%, respectively; the CD44+CD271+ cell percentage for TE1 stem-like spheres was 16.07% ± 0.91% vs 22.67% ± 1.12%, 16.07% ± 0.91% vs 33.27% ± 1.07%, respectively. The 4 and 8 Gy irradiated KYSE-150 and TE-1 stem-like spheres were compared with the 0 Gy irradiated group, and the differences were statistically significant (P < 0.05). CONCLUSION: The KYSE-150 and TE-1 stem-like spheres are more radioresistant than their parental cells which may suggest that cancer stem cells are related to radioresistance. PMID:25561796

Transplant of Hepatocytes, Undifferentiated Mesenchymal Stem Cells, and In Vitro Hepatocyte-Differentiated Mesenchymal Stem Cells in a Chronic Liver Failure Experimental Model: A Comparative Study.

PubMed

El Baz, Hanan; Demerdash, Zeinab; Kamel, Manal; Atta, Shimaa; Salah, Faten; Hassan, Salwa; Hammam, Olfat; Khalil, Heba; Meshaal, Safa; Raafat, Inas

2018-02-01

Liver transplant is the cornerstone line of treatment for chronic liver diseases; however, the long list of complications and obstacles stand against this operation. Searching for new modalities for treatment of chronic liver illness is a must. In the present research, we aimed to compare the effects of transplant of undifferentiated human mesenchymal stem cells, in vitro differentiated mesenchymal stem cells, and adult hepatocytes in an experimental model of chronic liver failure. Undifferentiated human cord blood mesenchymal stem cells were isolated, pro-pagated, and characterized by morphology, gene expression analysis, and flow cytometry of surface markers and in vitro differentiated into hepatocyte-like cells. Rat hepatocytes were isolated by double perfusion technique. An animal model of chronic liver failure was developed, and undifferentiated human cord blood mesenchymal stem cells, in vitro hepato-genically differentiated mesenchymal stem cells, or freshly isolated rat hepatocytes were transplanted into a CCL4 cirrhotic experimental model. Animals were killed 3 months after transplant, and liver functions and histopathology were assessed. Compared with the cirrhotic control group, the 3 cell-treated groups showed improved alanine aminotransferase, aspartate aminotransferase, albumin, and bilirubin levels, with best results shown in the hepatocyte-treated group. Histopathologic examination of the treated groups showed improved fibrosis, with best results obtained in the undifferentiated mesenchymal stem cell-treated group. Both adult hepatocytes and cord blood mesenchymal stem cells proved to be promising candidates for cell-based therapy in liver regeneration on an experimental level. Improved liver function was evident in the hepatocyte-treated group, and fibrosis control was more evident in the undifferentiated mesenchymal stem cell-treated group.

New perspectives in human stem cell therapeutic research.

PubMed

Trounson, Alan

2009-06-11

Human stem cells are in evaluation in clinical stem cell trials, primarily as autologous bone marrow studies, autologous and allogenic mesenchymal stem cell trials, and some allogenic neural stem cell transplantation projects. Safety and efficacy are being addressed for a number of disease state applications. There is considerable data supporting safety of bone marrow and mesenchymal stem cell transplants but the efficacy data are variable and of mixed benefit. Mechanisms of action of many of these cells are unknown and this raises the concern of unpredictable results in the future. Nevertheless there is considerable optimism that immune suppression and anti-inflammatory properties of mesenchymal stem cells will be of benefit for many conditions such as graft versus host disease, solid organ transplants and pulmonary fibrosis. Where bone marrow and mesenchymal stem cells are being studied for heart disease, stroke and other neurodegenerative disorders, again progress is mixed and mostly without significant benefit. However, correction of multiple sclerosis, at least in the short term is encouraging. Clinical trials on the use of embryonic stem cell derivatives for spinal injury and macular degeneration are beginning and a raft of other clinical trials can be expected soon, for example, the use of neural stem cells for killing inoperable glioma and embryonic stem cells for regenerating beta islet cells for diabetes. The change in attitude to embryonic stem cell research with the incoming Obama administration heralds a new co-operative environment for study and evaluation of stem cell therapies. The Californian stem cell initiative (California Institute for Regenerative Medicine) has engendered global collaboration for this new medicine that will now also be supported by the US Federal Government. The active participation of governments, academia, biotechnology, pharmaceutical companies, and private investment is a powerful consortium for advances in health.

Oscillatory Protein Expression Dynamics Endows Stem Cells with Robust Differentiation Potential

PubMed Central

Kaneko, Kunihiko

2011-01-01

The lack of understanding of stem cell differentiation and proliferation is a fundamental problem in developmental biology. Although gene regulatory networks (GRNs) for stem cell differentiation have been partially identified, the nature of differentiation dynamics and their regulation leading to robust development remain unclear. Herein, using a dynamical system modeling cell approach, we performed simulations of the developmental process using all possible GRNs with a few genes, and screened GRNs that could generate cell type diversity through cell-cell interactions. We found that model stem cells that both proliferated and differentiated always exhibited oscillatory expression dynamics, and the differentiation frequency of such stem cells was regulated, resulting in a robust number distribution. Moreover, we uncovered the common regulatory motifs for stem cell differentiation, in which a combination of regulatory motifs that generated oscillatory expression dynamics and stabilized distinct cellular states played an essential role. These findings may explain the recently observed heterogeneity and dynamic equilibrium in cellular states of stem cells, and can be used to predict regulatory networks responsible for differentiation in stem cell systems. PMID:22073296

TGFβ lengthens the G1 phase of stem cells in aged mouse brain.

PubMed

Daynac, Mathieu; Pineda, Jose R; Chicheportiche, Alexandra; Gauthier, Laurent R; Morizur, Lise; Boussin, François D; Mouthon, Marc-André

2014-12-01

Neurogenesis decreases during aging causing a progressive cognitive decline but it is still controversial whether proliferation defects in neurogenic niches result from a loss of neural stem cells or from an impairment of their progression through the cell cycle. Using an accurate fluorescence-activated cell sorting technique, we show that the pool of neural stem cells is maintained in the subventricular zone of middle-aged mice while they have a reduced proliferative potential eventually leading to the subsequent decrease of their progeny. In addition, we demonstrate that the G1 phase is lengthened during aging specifically in activated stem cells, but not in transit-amplifying cells, and directly impacts on neurogenesis. Finally, we report that inhibition of TGFβ signaling restores cell cycle progression defects in stem cells. Our data highlight the significance of cell cycle dysregulation in stem cells in the aged brain and provide an attractive foundation for the development of anti-TGFβ regenerative therapies based on stimulating endogenous neural stem cells. © 2014 AlphaMed Press.

[Using cell technologies to treat urologic diseases].

PubMed

Glybochko, P V; Olefir, Yu V; Alyaev, Yu G; Butnaru, D V; Bezrukov, E A; Chaplenko, A A; Zharikova, T M

2016-08-01

Stem and progenitor cells being introduced into the body have the ability to stimulate regeneration of tissues and organs by differentiating into specialized cells. Stem cell therapy is used in urology to treat various disorders, including erectile dysfunction, urinary incontinence, Peyronies disease, and male infertility. This review presents the results of international preclinical and clinical research on stem cell based medications for treating the above diseases. The most promising appears to be the use of adipose tissue-derived mesenchymal stem cells.

Inhibition of Aurora-A kinase induces cell cycle arrest in epithelial ovarian cancer stem cells by affecting NFκB pathway

PubMed Central

Alvero, Ayesha B; Visintin, Irene

2011-01-01

Recurrent ovarian cancer is resistant to conventional chemotherapy. A sub-population of ovarian cancer cells, the epithelial ovarian cancer stem cells (EOC stem cells) have stemness properties, constitutive NFκB activity, and represent the chemoresistant population. Currently, there is no effective treatment that targets these cells. Aurora-A kinase (Aurora-A) is associated with tumor initiation and progression and is overexpressed in numerous malignancies. The aim of this study is to determine the effect of Aurora-A inhibition in EOC stem cells. EOC stem cells were treated with the Aurora-A inhibitor, MK-5108. Cell growth was monitored by Incucyte real-time imaging system, cell viability was measured using the Celltiter 96 assay and cytokine levels were quantified using xMAP technology. The intracellular changes associated with MK-5108 treatment are: (1) polyploidy and cell cycle arrest; (2) inhibition of NFκB activity; (3) decreased cytokine production; and (4) nuclear accumulation of IκBα. Thus, inhibition of Aurora-A decreases cell proliferation in the EOC stem cells by inducing cell cycle arrest and affecting the NFκB pathway. As EOC stem cells represent a source of recurrence and chemoresistance, these results suggest that Aurora-A inhibition may effectively target the cancer stem cell population in ovarian cancer. PMID:21623171

Androgen deprivation and stem cell markers in prostate cancers

PubMed Central

Tang, Yao; Hamburger, Anne W; Wang, Linbo; Khan, Mohammad Afnan; Hussain, Arif

2010-01-01

In our previous studies using human LNCaP xenografts and TRAMP (transgenic adenocarcinoma of mouse prostate) mice, androgen deprivation therapy (ADT) resulted in a temporary cessation of prostate cancer (PCa) growth, but then tumors grew faster with more malignant behaviour. To understand whether cancer stem cells might play a role in PCa progression in these animal models, we investigated the expressions of stem cell-related markers in tumors at different time points after ADT. In both animal models, enhanced expressions of stem cell markers were observed in tumors of castrated mice, as compared to non-castrated controls. This increased cell population that expressed stem cell markers is designated as stem-like cells (SLC) in this article. We also observed that the SLC peaked at relatively early time points after ADT, before tumors resumed their growth. These results suggest that the SLC population may play a role in tumor re-growth and disease progression, and that targeting the SLC at their peak-expression time point may prevent tumor recurrence following ADT. PMID:20126580

Therapeutic application of stem cells in gastroenterology: an up-date.

PubMed

Burra, Patrizia; Bizzaro, Debora; Ciccocioppo, Rachele; Marra, Fabio; Piscaglia, Anna Chiara; Porretti, Laura; Gasbarrini, Antonio; Russo, Francesco Paolo

2011-09-14

Adult stem cells represent the self-renewing progenitors of numerous body tissues, and they are currently classified according to their origin and differentiation ability. In recent years, the research on stem cells has expanded enormously and holds therapeutic promises for many patients suffering from currently disabling diseases. This paper focuses on the possible use of stem cells in the two main clinical settings in gastroenterology, i.e., hepatic and intestinal diseases, which have a strong impact on public health worldwide. Despite encouraging results obtained in both regenerative medicine and immune-mediated conditions, further studies are needed to fully understand the biology of stem cells and carefully assess their putative oncogenic properties. Moreover, the research on stem cells arouses fervent ethical, social and political debate. The Italian Society of Gastroenterology sponsored a workshop on stem cells held in Verona during the XVI Congress of the Federation of Italian Societies of Digestive Diseases (March 6-9, 2010). Here, we report on the issues discussed, including liver and intestinal diseases that may benefit from stem cell therapy, the biology of hepatic and intestinal tissue repair, and stem cell usage in clinical trials.

Evaluation of the osteogenic differentiation of gingiva-derived stem cells grown on culture plates or in stem cell spheroids: Comparison of two- and three-dimensional cultures.

PubMed

Lee, Sung-Il; Ko, Youngkyung; Park, Jun-Beom

2017-09-01

Three-dimensional cell culture systems provide a convenient in vitro model for the study of complex cell-cell and cell-matrix interactions in the absence of exogenous substrates. The current study aimed to evaluate the osteogenic differentiation potential of gingiva-derived stem cells cultured in two-dimensional or three-dimensional systems. To the best of our knowledge, the present study is the first to compare the growth of gingiva-derived stem cells in monolayer culture to a three-dimensional culture system with microwells. For three-dimensional culture, gingiva-derived stem cells were isolated and seeded into polydimethylsiloxane-based concave micromolds. Alkaline phosphatase activity and alizarin red S staining assays were then performed to evaluate osteogenesis and the degree of mineralization, respectively. Stem cell spheroids had a significantly increased level of alkaline phosphatase activity and mineralization compared with cells from the two-dimensional culture. In addition, an increase in mineralized deposits was observed with an increase in the loading cell number. The results of present study indicate that gingiva-derived stem cell spheroids exhibit an increased osteogenic potential compared with stem cells from two-dimensional culture. This highlights the potential of three-dimensional culture systems using gingiva-derived stem cells for regenerative medicine applications requiring stem cells with osteogenic potential.

Stem cells and cancer of the stomach and intestine.

PubMed

Vries, Robert G J; Huch, Meritxell; Clevers, Hans

2010-10-01

Cancer in the 21st century has become the number one cause of death in developed countries. Although much progress has been made in improving patient survival, tumour relapse is one of the important causes of cancer treatment failure. An early observation in the study of cancer was the heterogeneity of tumours. Traditionally, this was explained by a combination of genomic instability of tumours and micro environmental factors leading to diverse phenotypical characteristics. It was assumed that cells in a tumour have an equal capacity to propagate the cancer. This model is currently known as the stochastic model. Recently, the Cancer stem cell model has been proposed to explain the heterogeneity of a tumour and its progression. According to this model, the heterogeneity of tumours is the result of aberrant differentiation of tumour cells into the cells of the tissue the tumour originated from. Tumours were suggested to contain stem cell-like cells, the cancer stem cells or tumour-initiating cells, which are uniquely capable of propagating a tumour much like normal stem cells fuel proliferation and differentiation in normal tissue. In this review we discuss the normal stem cell biology of the stomach and intestine followed by both the stochastic and cancer stem cell models in light of recent findings in the gastric and intestinal systems. The molecular pathways underlying normal and tumourigenic growth have been well studied, and recently the stem cells of the stomach and intestine have been identified. Furthermore, intestinal stem cells were identified as the cells-of-origin of colon cancer upon loss of the tumour suppressor APC. Lastly, several studies have proposed the positive identification of a cancer stem cell of human colon cancer. At the end we compare the cancer stem cell model and the stochastic model. We conclude that clonal evolution of tumour cells resulting from genetic mutations underlies tumour initiation and progression in both cancer models. This implies that at any point during tumour development any tumour cell can revert to a cancer stem cell after having gained a clonal advantage over the original cancer stem cell. Therefore, these models represent two sides of the same coin. Copyright © 2010 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.

Hyperglycemic Stress Impairs the Stemness Capacity of Kidney Stem Cells in Rats.

PubMed

Yang, Guang; Jia, Yali; Li, Chunlin; Cheng, Qingli; Yue, Wen; Pei, Xuetao

2015-01-01

The incidence of acute kidney injury in patients with diabetes is significantly higher than that of patients without diabetes, and may be associated with the poor stemness capacity of kidney stem cells (KSCs) and limited recovery of injured renal tubules. To investigate the effects of hyperglycemic stress on KSC stemness, KSCs were isolated from the rat renal papilla and analyzed for their self-renewal and differentiation abilities. Our results showed that isolated KSCs expressed the mesenchymal stem cell markers N-cadherin, Nestin, CD133, CD29, CD90, and CD73. Moreover, KSCs co-cultured with hypoxia-injured renal tubular epithelial cell (RTECs) induced the expression of the mature epithelial cell marker CK18, suggesting that the KSCs could differentiate into RTECs in vitro. However, KSC proliferation, differentiation ability and tolerance to hypoxia were decreased in high-glucose cultures. Taken together, these results suggest the high-glucose microenvironment can damage the reparative ability of KSCs. It may result in a decreased of recovery capability of renal tubules from injury.

MicroRNA let-7b regulates neural stem cell proliferation and differentiation by targeting nuclear receptor TLX signaling

PubMed Central

Zhao, Chunnian; Sun, GuoQiang; Li, Shengxiu; Lang, Ming-Fei; Yang, Su; Li, Wendong; Shi, Yanhong

2010-01-01

Neural stem cell self-renewal and differentiation is orchestrated by precise control of gene expression involving nuclear receptor TLX. Let-7b, a member of the let-7 microRNA family, is expressed in mammalian brains and exhibits increased expression during neural differentiation. However, the role of let-7b in neural stem cell proliferation and differentiation remains unknown. Here we show that let-7b regulates neural stem cell proliferation and differentiation by targeting the stem cell regulator TLX and the cell cycle regulator cyclin D1. Overexpression of let-7b led to reduced neural stem cell proliferation and increased neural differentiation, whereas antisense knockdown of let-7b resulted in enhanced proliferation of neural stem cells. Moreover, in utero electroporation of let-7b to embryonic mouse brains led to reduced cell cycle progression in neural stem cells. Introducing an expression vector of Tlx or cyclin D1 that lacks the let-7b recognition site rescued let-7b-induced proliferation deficiency, suggesting that both TLX and cyclin D1 are important targets for let-7b-mediated regulation of neural stem cell proliferation. Let-7b, by targeting TLX and cyclin D1, establishes an efficient strategy to control neural stem cell proliferation and differentiation. PMID:20133835

MicroRNA let-7b regulates neural stem cell proliferation and differentiation by targeting nuclear receptor TLX signaling.

PubMed

Zhao, Chunnian; Sun, GuoQiang; Li, Shengxiu; Lang, Ming-Fei; Yang, Su; Li, Wendong; Shi, Yanhong

2010-02-02

Neural stem cell self-renewal and differentiation is orchestrated by precise control of gene expression involving nuclear receptor TLX. Let-7b, a member of the let-7 microRNA family, is expressed in mammalian brains and exhibits increased expression during neural differentiation. However, the role of let-7b in neural stem cell proliferation and differentiation remains unknown. Here we show that let-7b regulates neural stem cell proliferation and differentiation by targeting the stem cell regulator TLX and the cell cycle regulator cyclin D1. Overexpression of let-7b led to reduced neural stem cell proliferation and increased neural differentiation, whereas antisense knockdown of let-7b resulted in enhanced proliferation of neural stem cells. Moreover, in utero electroporation of let-7b to embryonic mouse brains led to reduced cell cycle progression in neural stem cells. Introducing an expression vector of Tlx or cyclin D1 that lacks the let-7b recognition site rescued let-7b-induced proliferation deficiency, suggesting that both TLX and cyclin D1 are important targets for let-7b-mediated regulation of neural stem cell proliferation. Let-7b, by targeting TLX and cyclin D1, establishes an efficient strategy to control neural stem cell proliferation and differentiation.

Foxi3 deficiency compromises hair follicle stem cell specification and activation

PubMed Central

Shirokova, Vera; Biggs, Leah C.; Jussila, Maria; Ohyama, Takahiro; Groves, Andrew K.; Mikkola, Marja L.

2017-01-01

The hair follicle is an ideal system to study stem cell specification and homeostasis due to its well characterized morphogenesis and stereotypic cycles of stem cell activation upon each hair cycle to produce a new hair shaft. The adult hair follicle stem cell niche consists of two distinct populations, the bulge and the more activation-prone secondary hair germ. Hair follicle stem cells are set aside during early stages of morphogenesis. This process is known to depend on the Sox9 transcription factor, but otherwise the establishment of the hair follicle stem cell niche is poorly understood. Here we show that that mutation of Foxi3, a Forkhead family transcription factor mutated in several hairless dog breeds, compromises stem cell specification. Further, loss of Foxi3 impedes hair follicle downgrowth and progression of the hair cycle. Genome-wide profiling revealed a number of downstream effectors of Foxi3 including transcription factors with a recognized function in hair follicle stem cells such as Lhx2, Runx1, and Nfatc1, suggesting that the Foxi3 mutant phenotype results from simultaneous downregulation of several stem cell signature genes. We show that Foxi3 displays a highly dynamic expression pattern during hair morphogenesis and cycling, and identify Foxi3 as a novel secondary hair germ marker. Absence of Foxi3 results in poor hair regeneration upon hair plucking, and a sparse fur phenotype in unperturbed mice that exacerbates with age, caused by impaired secondary hair germ activation leading to progressive depletion of stem cells. Thus, Foxi3 regulates multiple aspects of hair follicle development and homeostasis. PMID:26992132

The Evolution of the Stem Cell Theory for Heart Failure

PubMed Central

Silvestre, Jean-Sébastien; Menasché, Philippe

2015-01-01

Various stem cell-based approaches for cardiac repair have achieved encouraging results in animal experiments, often leading to their rapid proceeding to clinical testing. However, freewheeling evolutionary developments of the stem cell theory might lead to dystopian scenarios where heterogeneous sources of therapeutic cells could promote mixed clinical outcomes in un-stratified patient populations. This review focuses on the lessons that should be learnt from the first generation of stem cell-based strategies and emphasizes the absolute requirement to better understand the basic mechanisms of stem cell biology and cardiogenesis. We will also discuss about the unexpected “big bang” in the stem cell theory, “blasting” the therapeutic cells to their unchallenged ability to release paracrine factors such as extracellular membrane vesicles. Paradoxically, the natural evolution of the stem cell theory for cardiac regeneration may end with the development of cell-free strategies with multiple cellular targets including cardiomyocytes but also other infiltrating or resident cardiac cells. PMID:26844266

Stem Cell-Based Therapies for Polyglutamine Diseases.

PubMed

Mendonça, Liliana S; Onofre, Isabel; Miranda, Catarina Oliveira; Perfeito, Rita; Nóbrega, Clévio; de Almeida, Luís Pereira

2018-01-01

Polyglutamine (polyQ) diseases are a family of neurodegenerative disorders with very heterogeneous clinical presentations, although with common features such as progressive neuronal death. Thus, at the time of diagnosis patients might present an extensive and irreversible neuronal death demanding cell replacement or support provided by cell-based therapies. For this purpose stem cells, which include diverse populations ranging from embryonic stem cells (ESCs), to fetal stem cells, mesenchymal stromal cells (MSCs) or induced pluripotent stem cells (iPSCs) have remarkable potential to promote extensive brain regeneration and recovery in neurodegenerative disorders. This regenerative potential has been demonstrated in exciting pre and clinical assays. However, despite these promising results, several drawbacks are hampering their successful clinical implementation. Problems related to ethical issues, quality control of the cells used and the lack of reliable models for the efficacy assessment of human stem cells. In this chapter the main advantages and disadvantages of the available sources of stem cells as well as their efficacy and potential to improve disease outcomes are discussed.

Isolation and evaluation of dental pulp stem cells from teeth with advanced periodontal disease.

PubMed

Derakhshani, Ali; Raoof, Maryam; Dabiri, Shahriar; Farsinejad, Ali Reza; Gorjestani, Hedayat; Yaghoobi, Mohammad Mehdi; Shokouhinejad, Noushin; Ehsani, Maryam

2015-04-01

Successful isolation of mesenchymal stem cells from waste tissues might be extremely promising for developing stem cell-based therapies. This study aimed to explore whether cells retrieved from teeth extracted due to advanced periodontal disease present mesenchymal stem cell-like properties. Pulp cells were isolated from 15 intact molars and 15 teeth with advanced periodontal disease. Cell proliferation and markers of mesenchymal stem cells were evaluated. Based on the RT-PCR and agarose gel electrophoresis, nucleostemin, Oct-4 and jmj2c, but not Nanog, were expressed in undifferentiated mesenchymal stem cells of both groups. Interestingly, diseased pulp exhibited higher gene expressions although it was not statistically significant. The average percentage of BrdU positive cells in the diseased group (84.4%, n = 5) was significantly higher than that of the control group (65.4%, n = 5) (t-test, P = 0.001). Our results indicate the successful isolation of mesenchymal stem cells from the pulp tissue of hopeless periodontally involved teeth.

Loss of Anterior Gradient 2 (Agr2) Expression Results in Hyperplasia and Defective Lineage Maturation in the Murine Stomach*

PubMed Central

Gupta, Aparna; Wodziak, Dariusz; Tun, May; Bouley, Donna M.; Lowe, Anson W.

2013-01-01

Recent studies of epithelial tissues have revealed the presence of tissue-specific stem cells that are able to establish multiple cell lineages within an organ. The stem cells give rise to progenitors that replicate before differentiating into specific cell lineages. The mechanism by which homeostasis is established between proliferating stem or progenitor cells and terminally differentiated cells is unclear. This study demonstrates that Agr2 expression by mucous neck cells in the stomach promotes the differentiation of multiple cell lineages while also inhibiting the proliferation of stem or progenitor cells. When Agr2 expression is absent, gastric mucous neck cells increased in number as does the number of proliferating cells. Agr2 expression loss also resulted in the decline of terminally differentiated cells, which was supplanted by cells that exhibited nuclear SOX9 labeling. Sox9 expression has been associated with progenitor and stem cells. Similar effects of the Agr2 null on cell proliferation in the intestine were also observed. Agr2 consequently serves to maintain the balance between proliferating and differentiated epithelial cells. PMID:23209296

Development of iPS (induced pluripotent stem cells) using natural product from extract of fish oocyte to provide stem cell for regenerative therapy

NASA Astrophysics Data System (ADS)

Meilany, Sofy; Firdausiyah, Qonitha S.; Naroeni, Aroem

2017-02-01

In this study, we developed a method to induce pluripotency of adult cells (fibroblast) into stem cells using a natural product, extract of fish oocyte, by comparing the extract concentration, 1 mg/ml and 2 mg/ml. The analyses were done by measuring the Nanog gene expression in cells using qPCR and detecting fibroblast marker anti H2-KK. The results revealed existence of a colony of stem cells in the cell that was induced with 2mg/ml concentration of oocytes. Nanoggene expression was analyzed by qPCR and the results showed expression of Nanog gene compared to the control. Analysis of result of fibroblast using Tali Cytometer and anti H2KK antibody showed loss of expression of Anti H2KK meaning there was transformation from fibroblast type cell to pluripotent cell type.

Mesenchymal Stem Cell Therapy for the Treatment of Vocal Fold Scarring: A Systematic Review of Preclinical Studies.

PubMed

Wingstrand, Vibe Lindeblad; Grønhøj Larsen, Christian; Jensen, David H; Bork, Kristian; Sebbesen, Lars; Balle, Jesper; Fischer-Nielsen, Anne; von Buchwald, Christian

2016-01-01

Therapy with mesenchymal stem cells exhibits potential for the development of novel interventions for many diseases and injuries. The use of mesenchymal stem cells in regenerative therapy for vocal fold scarring exhibited promising results to reduce stiffness and enhance the biomechanical properties of injured vocal folds. This study evaluated the biomechanical effects of mesenchymal stem cell therapy for the treatment of vocal fold scarring. PubMed, Embase, the Cochrane Library and Google Scholar were searched. Controlled studies that assessed the biomechanical effects of mesenchymal stem cell therapy for the treatment of vocal fold scarring were included. Primary outcomes were viscoelastic properties and mucosal wave amplitude. Seven preclinical animal studies (n = 152 single vocal folds) were eligible for inclusion. Evaluation of viscoelastic parameters revealed a decreased dynamic viscosity (η') and elastic modulus (G'), i.e., decreased resistance and stiffness, in scarred vocal folds treated with mesenchymal stem cells compared to non-treated scarred vocal folds. Mucosal wave amplitude was increased in scarred vocal folds treated with mesenchymal stem cells vs. non-treated scarred vocal folds. The results from these studies suggest an increased regenerative effect of therapy with mesenchymal stem cells for scarred vocal folds and are encouraging for further clinical studies.

CXCR4/CXCL12 signaling impacts enamel progenitor cell proliferation and motility in the dental stem cell niche

PubMed Central

Otsu, Keishi; Harada, Hidemitsu; Shibata, Shunichi; Obara, Nobuko; Irie, Kazuharu; Taniguchi, Akiyoshi; Nagasawa, Takashi; Aoki, Kazunari; Caliari, Steven R.; Weisgerber, Daniel W.

2015-01-01

Dental stem cells are located at the proximal ends of rodent incisors. These stem cells reside in the dental epithelial stem cell niche, termed the apical bud. We focused on identifying critical features of a chemotactic signal in the niche. Here, we report that CXCR4/CXCL12 signaling impacts enamel progenitor cell proliferation and motility in dental stem cell niche cells. We report cells in the apical bud express CXCR4 mRNA at high levels while expression is restricted in the basal epithelium (BE) and transit-amplifying (TA) cell regions. Furthermore, the CXCL12 ligand is present in mesenchymal cells adjacent to the apical bud. We then performed gain- and loss-of-function analyses to better elucidate the role of CXCR4 and CXCL12. CXCR4-deficient mice contain epithelial cell aggregates, while cell proliferation in mutant incisors was also significantly reduced. We demonstrate in vitro that dental epithelial cells migrate toward sources of CXCL12, whereas knocking down CXCR4 impaired motility and resulted in formation of dense cell colonies. These results suggest that CXCR4 expression may be critical for activation of enamel progenitor cell division and that CXCR4/CXCL12 signaling may control movement of epithelial progenitors from the dental stem cell niche. PMID:26246398

Generation of hematopoietic stem cells from human embryonic stem cells using a defined, stepwise, serum-free, and serum replacement-free monolayer culture method.

PubMed

Kim, So-Jung; Jung, Ji-Won; Ha, Hye-Yeong; Koo, Soo Kyung; Kim, Eung-Gook; Kim, Jung-Hyun

2017-03-01

Embryonic stem cells (ESCs) can be expanded infinitely in vitro and have the potential to differentiate into hematopoietic stem cells (HSCs); thus, they are considered a useful source of cells for HSC production. Although several technical in vitro methods for engineering HSCs from pluripotent stem cells have been developed, clinical application of HSCs engineered from pluripotent stem cells is restricted because of the possibility of xenogeneic contamination resulting from the use of murine materials. Human ESCs (CHA-hES15) were cultured on growth factor-reduced Matrigel-coated dishes in the mTeSR1 serum-free medium. When the cells were 70% confluent, we initiated HSC differentiation by three methods involving (1) knockout serum replacement (KSR), cytokines, TGFb1, EPO, and FLT3L; (2) KSR, cytokines, and bFGF; or (3) cytokines and bFGF. Among the three differentiation methods, the minimal number of cytokines without KSR resulted in the greatest production of HSCs. The optimized method resulted in a higher proportion of CD34 + CD43 + hematopoietic progenitor cells (HPCs) and CD34 + CD45 + HPCs compared to the other methods. In addition, the HSCs showed the potential to differentiate into multiple lineages of hematopoietic cells in vitro . In this study, we optimized a two-step, serum-free, animal protein-free, KSR-free, feeder-free, chemically defined monolayer culture method for generation of HSCs and hematopoietic stem and progenitor cells (HSPCs) from human ESCs.

Stem cells in clinical practice: applications and warnings.

PubMed

Lodi, Daniele; Iannitti, Tommaso; Palmieri, Beniamino

2011-01-17

Stem cells are a relevant source of information about cellular differentiation, molecular processes and tissue homeostasis, but also one of the most putative biological tools to treat degenerative diseases. This review focuses on human stem cells clinical and experimental applications. Our aim is to take a correct view of the available stem cell subtypes and their rational use in the medical area, with a specific focus on their therapeutic benefits and side effects. We have reviewed the main clinical trials dividing them basing on their clinical applications, and taking into account the ethical issue associated with the stem cell therapy. We have searched Pubmed/Medline for clinical trials, involving the use of human stem cells, using the key words "stem cells" combined with the key words "transplantation", "pathology", "guidelines", "properties" and "risks". All the relevant clinical trials have been included. The results have been divided into different categories, basing on the way stem cells have been employed in different pathological conditions.

Leptin enhances the invasive ability of glioma stem-like cells depending on leptin receptor expression.

PubMed

Han, Guosheng; Zhao, Wenyuan; Wang, Laixing; Yue, Zhijian; Zhao, Rui; Li, Yanan; Zhou, Xiaoping; Hu, Xiaowu; Liu, Jianmin

2014-01-16

Glioma stem-like cells have been demonstrated to have highly invasive activity, which is the major cause of glioma recurrence after therapy. Leptin plays a role in glioma invasion, however, whether and how leptin contributes to the biological properties of glioma stem-like cells, such as invasion, remains to be explored. In the current study, we aimed to explore the role of leptin during glioma stem-like cells invasion as well as the signaling pathway. We found that glioma stem-like cells exhibited high invasive potential, especially in the presence of leptin, Ob-R coexpressed with CD133 in glioma stem-like cells was showed to be responsible for leptin mediated invasion of glioma stem-like cells. Our results indicated that leptin served as a key intermediary linking the accumulation of excess adipokine to the invasion of glioma stem-like cells, which may be a novel therapeutic target for suppressing tumor invasion and recurrence. © 2013 Published by Elsevier B.V.

Adult Stem Cells and Diseases of Aging

PubMed Central

Boyette, Lisa B.; Tuan, Rocky S.

2014-01-01

Preservation of adult stem cells pools is critical for maintaining tissue homeostasis into old age. Exhaustion of adult stem cell pools as a result of deranged metabolic signaling, premature senescence as a response to oncogenic insults to the somatic genome, and other causes contribute to tissue degeneration with age. Both progeria, an extreme example of early-onset aging, and heritable longevity have provided avenues to study regulation of the aging program and its impact on adult stem cell compartments. In this review, we discuss recent findings concerning the effects of aging on stem cells, contributions of stem cells to age-related pathologies, examples of signaling pathways at work in these processes, and lessons about cellular aging gleaned from the development and refinement of cellular reprogramming technologies. We highlight emerging therapeutic approaches to manipulation of key signaling pathways corrupting or exhausting adult stem cells, as well as other approaches targeted at maintaining robust stem cell pools to extend not only lifespan but healthspan. PMID:24757526

The epithelial-mesenchymal transition generates cells with properties of stem cells.

PubMed

Mani, Sendurai A; Guo, Wenjun; Liao, Mai-Jing; Eaton, Elinor Ng; Ayyanan, Ayyakkannu; Zhou, Alicia Y; Brooks, Mary; Reinhard, Ferenc; Zhang, Cheng Cheng; Shipitsin, Michail; Campbell, Lauren L; Polyak, Kornelia; Brisken, Cathrin; Yang, Jing; Weinberg, Robert A

2008-05-16

The epithelial-mesenchymal transition (EMT) is a key developmental program that is often activated during cancer invasion and metastasis. We here report that the induction of an EMT in immortalized human mammary epithelial cells (HMLEs) results in the acquisition of mesenchymal traits and in the expression of stem-cell markers. Furthermore, we show that those cells have an increased ability to form mammospheres, a property associated with mammary epithelial stem cells. Independent of this, stem cell-like cells isolated from HMLE cultures form mammospheres and express markers similar to those of HMLEs that have undergone an EMT. Moreover, stem-like cells isolated either from mouse or human mammary glands or mammary carcinomas express EMT markers. Finally, transformed human mammary epithelial cells that have undergone an EMT form mammospheres, soft agar colonies, and tumors more efficiently. These findings illustrate a direct link between the EMT and the gain of epithelial stem cell properties.

Cellular internalization of LiNbO3 nanocrystals for second harmonic imaging and the effects on stem cell differentiation

NASA Astrophysics Data System (ADS)

Li, Jianhua; Qiu, Jichuan; Guo, Weibo; Wang, Shu; Ma, Baojin; Mou, Xiaoning; Tanes, Michael; Jiang, Huaidong; Liu, Hong

2016-03-01

Second harmonic generation (SHG) nanocrystals have recently been reported to label cancer cells and other functional cell lines due to their unique double-frequency property. In this paper, we report for the first time the use of lithium niobate (LiNbO3, LN) nanocrystals as SHG labels for imaging stem cells. Rat mesenchymal stem cells (rMSCs) were labeled with LN nanocrystals in order to study the cellular internalization of the nanocrystals and the influence on stem cell differentiation. The results showed that LN nanocrystals were endocytosed by the rMSCs and the distribution of the internalized nanoparticles demonstrated a high consistency with the orientation of the actin filaments. Besides, LN-labeled rMSCs showed a concentration-dependent viability. Most importantly, rMSCs labeled with 50 μg per mL of LN nanocrystals retained their ability to differentiate into both osteogenic and adipogenic lineages. The results prove that LN nanocrystals can be used as a cytocompatible, near-infrared (NIR) light driven cell label for long-term imaging, without hindering stem cell differentiation. This work will promote the use of LN nanocrystals to broader applications like deep-tissue tracking, remote drug delivery and stem cell therapy.Second harmonic generation (SHG) nanocrystals have recently been reported to label cancer cells and other functional cell lines due to their unique double-frequency property. In this paper, we report for the first time the use of lithium niobate (LiNbO3, LN) nanocrystals as SHG labels for imaging stem cells. Rat mesenchymal stem cells (rMSCs) were labeled with LN nanocrystals in order to study the cellular internalization of the nanocrystals and the influence on stem cell differentiation. The results showed that LN nanocrystals were endocytosed by the rMSCs and the distribution of the internalized nanoparticles demonstrated a high consistency with the orientation of the actin filaments. Besides, LN-labeled rMSCs showed a concentration-dependent viability. Most importantly, rMSCs labeled with 50 μg per mL of LN nanocrystals retained their ability to differentiate into both osteogenic and adipogenic lineages. The results prove that LN nanocrystals can be used as a cytocompatible, near-infrared (NIR) light driven cell label for long-term imaging, without hindering stem cell differentiation. This work will promote the use of LN nanocrystals to broader applications like deep-tissue tracking, remote drug delivery and stem cell therapy. Electronic supplementary information (ESI) available. See DOI: 10.1039/c6nr00785f

Complexity in cancer stem cells and tumor evolution: Toward precision medicine.

PubMed

La Porta, Caterina A M; Zapperi, Stefano

2017-06-01

In this review, we discuss recent advances on the plasticity of cancer stem cells and highlight their relevance to understand the metastatic process and to guide therapeutic interventions. Recent results suggest that the strict hierarchical structure of cancer cell populations advocated by the cancer stem cell model must be reconsidered since the depletion of cancer stem cells leads the other tumor cells to switch back into the cancer stem cell phenotype. This plasticity has important implications for metastasis since migrating cells do not need to be cancer stem cells in order to seed a metastasis. We also discuss the important role of the immune system and the microenvironment in modulating phenotypic switching and suggest possible avenues to exploit our understanding of this process to develop an effective strategy for precision medicine. Copyright © 2017 Elsevier Ltd. All rights reserved.

β-Cell Replacement in Mice Using Human Type 1 Diabetes Nuclear Transfer Embryonic Stem Cells.

PubMed

Sui, Lina; Danzl, Nichole; Campbell, Sean R; Viola, Ryan; Williams, Damian; Xing, Yuan; Wang, Yong; Phillips, Neil; Poffenberger, Greg; Johannesson, Bjarki; Oberholzer, Jose; Powers, Alvin C; Leibel, Rudolph L; Chen, Xiaojuan; Sykes, Megan; Egli, Dieter

2018-01-01

β-Cells derived from stem cells hold great promise for cell replacement therapy for diabetes. Here we examine the ability of nuclear transfer embryonic stem cells (NT-ESs) derived from a patient with type 1 diabetes to differentiate into β-cells and provide a source of autologous islets for cell replacement. NT-ESs differentiate in vitro with an average efficiency of 55% into C-peptide-positive cells, expressing markers of mature β-cells, including MAFA and NKX6.1. Upon transplantation in immunodeficient mice, grafted cells form vascularized islet-like structures containing MAFA/C-peptide-positive cells. These β-cells adapt insulin secretion to ambient metabolite status and show normal insulin processing. Importantly, NT-ES-β-cells maintain normal blood glucose levels after ablation of the mouse endogenous β-cells. Cystic structures, but no teratomas, were observed in NT-ES-β-cell grafts. Isogenic induced pluripotent stem cell lines showed greater variability in β-cell differentiation. Even though different methods of somatic cell reprogramming result in stem cell lines that are molecularly indistinguishable, full differentiation competence is more common in ES cell lines than in induced pluripotent stem cell lines. These results demonstrate the suitability of NT-ES-β-cells for cell replacement for type 1 diabetes and provide proof of principle for therapeutic cloning combined with cell therapy. © 2017 by the American Diabetes Association.

From fibroblasts and stem cells: implications for cell therapies and somatic cloning.

PubMed

Kues, Wilfried A; Carnwath, Joseph W; Niemann, Heiner

2005-01-01

Pluripotent embryonic stem cells (ESCs) from the inner cell mass of early murine and human embryos exhibit extensive self-renewal in culture and maintain their ability to differentiate into all cell lineages. These features make ESCs a suitable candidate for cell-replacement therapy. However, the use of early embryos has provoked considerable public debate based on ethical considerations. From this standpoint, stem cells derived from adult tissues are a more easily accepted alternative. Recent results suggest that adult stem cells have a broader range of potency than imagined initially. Although some claims have been called into question by the discovery that fusion between the stem cells and differentiated cells can occur spontaneously, in other cases somatic stem cells have been induced to commit to various lineages by the extra- or intracellular environment. Recent data from our laboratory suggest that changes in culture conditions can expand a subpopulation of cells with a pluripotent phenotype from primary fibroblast cultures. The present paper critically reviews recent data on the potency of somatic stem cells, methods to modify the potency of somatic cells and implications for cell-based therapies.

Cerebellar stem cells do not produce neurons and astrocytes in adult mouse

DOE Office of Scientific and Technical Information (OSTI.GOV)

Su, Xin; Guan, Wuqiang; Yu, Yong-Chun

Highlights: • No new neurons and astrocytes are generated in adult mouse cerebellum. • Very few mash1{sup +} or nestin{sup +} stem cells exist, and most of them are quiescent. • Cell proliferation rate is diversified among cerebellar regions and decreases over time. - Abstract: Although previous studies implied that cerebellar stem cells exist in some adult mammals, little is known about whether these stem cells can produce new neurons and astrocytes. In this study by bromodeoxyuridine (BrdU) intraperitoneal (i.p.) injection, we found that there are abundant BrdU{sup +} cells in adult mouse cerebellum, and their quantity and density decreasesmore » significantly over time. We also found cell proliferation rate is diversified in different cerebellar regions. Among these BrdU{sup +} cells, very few are mash1{sup +} or nestin{sup +} stem cells, and the vast majority of cerebellar stem cells are quiescent. Data obtained by in vivo retrovirus injection indicate that stem cells do not produce neurons and astrocytes in adult mouse cerebellum. Instead, some cells labeled by retrovirus are Iba1{sup +} microglia. These results indicate that very few stem cells exist in adult mouse cerebellum, and none of these stem cells contribute to neurogenesis and astrogenesis under physiological condition.« less

Deubiquitylating enzymes as cancer stem cell therapeutics.

PubMed

Haq, Saba; Suresh, Bharathi; Ramakrishna, Suresh

2018-01-01

The focus of basic and applied research on core stem cell transcription factors has paved the way to initial delineation of their characteristics, their regulatory mechanisms, and the applicability of their regulatory proteins for protein-induced pluripotent stem cells (protein-IPSC) generation and in further clinical settings. Striking parallels have been observed between cancer stem cells (CSCs) and stem cells. For the maintenance of stem cells and CSC pluripotency and differentiation, post translational modifications (i.e., ubiquitylation and deubiquitylation) are tightly regulated, as these modifications result in a variety of stem cell fates. The identification of deubiquitylating enzymes (DUBs) involved in the regulation of core stem cell transcription factors and CSC-related proteins might contribute to providing novel insights into the implications of DUB regulatory mechanisms for governing cellular reprogramming and carcinogenesis. Moreover, we propose the novel possibility of applying DUBs coupled with core transcription factors to improve protein-iPSC generation efficiency. Additionally, this review article further illustrates the potential of applying DUB inhibitors as a novel therapeutic intervention for targeting CSCs. Thus, defining DUBs as core pharmacological targets implies that future endeavors to develop their inhibitors may revolutionize our ability to regulate stem cell maintenance and differentiation, somatic cell reprogramming, and cancer stem cells. Copyright © 2017 Elsevier B.V. All rights reserved.

Ocular stem cells: a status update!

PubMed Central

2014-01-01

Stem cells are unspecialized cells that have been a major focus of the field of regenerative medicine, opening new frontiers and regarded as the future of medicine. The ophthalmology branch of the medical sciences was the first to directly benefit from stem cells for regenerative treatment. The success stories of regenerative medicine in ophthalmology can be attributed to its accessibility, ease of follow-up and the eye being an immune-privileged organ. Cell-based therapies using stem cells from the ciliary body, iris and sclera are still in animal experimental stages but show potential for replacing degenerated photoreceptors. Limbal, corneal and conjunctival stem cells are still limited for use only for surface reconstruction, although they might have potential beyond this. Iris pigment epithelial, ciliary body epithelial and choroidal epithelial stem cells in laboratory studies have shown some promise for retinal or neural tissue replacement. Trabecular meshwork, orbital and sclera stem cells have properties identical to cells of mesenchymal origin but their potential has yet to be experimentally determined and validated. Retinal and retinal pigment epithelium stem cells remain the most sought out stem cells for curing retinal degenerative disorders, although treatments using them have resulted in variable outcomes. The functional aspects of the therapeutic application of lenticular stem cells are not known and need further attention. Recently, embryonic stem cell-derived retinal pigment epithelium has been used for treating patients with Stargardts disease and age-related macular degeneration. Overall, the different stem cells residing in different components of the eye have shown some success in clinical and animal studies in the field of regenerative medicine. PMID:25158127

Induction of endoplasmic reticulum stress by deletion of Grp78 depletes Apc mutant intestinal epithelial stem cells.

PubMed

van Lidth de Jeude, J F; Meijer, B J; Wielenga, M C B; Spaan, C N; Baan, B; Rosekrans, S L; Meisner, S; Shen, Y H; Lee, A S; Paton, J C; Paton, A W; Muncan, V; van den Brink, G R; Heijmans, J

2017-06-15

Intestinal epithelial stem cells are highly sensitive to differentiation induced by endoplasmic reticulum (ER) stress. Colorectal cancer develops from mutated intestinal epithelial stem cells. The most frequent initiating mutation occurs in Apc, which results in hyperactivated Wnt signalling. This causes hyperproliferation and reduced sensitivity to chemotherapy, but whether these mutated stem cells are sensitive to ER stress induced differentiation remains unknown. Here we examined this by generating mice in which both Apc and ER stress repressor chaperone Grp78 can be conditionally deleted from the intestinal epithelium. For molecular studies, we used intestinal organoids derived from these mice. Homozygous loss of Apc alone resulted in crypt elongation, activation of the Wnt signature and accumulation of intestinal epithelial stem cells, as expected. This phenotype was however completely rescued on activation of ER stress by additional deletion of Grp78. In these Apc-Grp78 double mutant animals, stem cells were rapidly lost and repopulation occurred by non-mutant cells that had escaped recombination, suggesting that Apc-Grp78 double mutant stem cells had lost self-renewal capacity. Although in Apc-Grp78 double mutant mice the Wnt signature was lost, these intestines exhibited ubiquitous epithelial presence of nuclear β-catenin. This suggests that ER stress interferes with Wnt signalling downstream of nuclear β-catenin. In conclusion, our findings indicate that ER stress signalling results in loss of Apc mutated intestinal epithelial stem cells by interference with the Wnt signature. In contrast to many known inhibitors of Wnt signalling, ER stress acts downstream of β-catenin. Therefore, ER stress poses a promising target in colorectal cancers, which develop as a result of Wnt activating mutations.

Paneth and intestinal stem cells preserve their functional integrity during worsening of acute cellular rejection in small bowel transplantation.

PubMed

Pucci Molineris, M; Gonzalez Polo, V; Perez, F; Ramisch, D; Rumbo, M; Gondolesi, G E; Meier, D

2018-04-01

Graft survival after small bowel transplantation remains impaired due to acute cellular rejection (ACR), the leading cause of graft loss. Although it was shown that the number of enteroendocrine progenitor cells in intestinal crypts was reduced during mild ACR, no results of Paneth and intestinal stem cells localized at the crypt bottom have been shown so far. Therefore, we wanted to elucidate integrity and functionality of the Paneth and stem cells during different degrees of ACR, and to assess whether these cells are the primary targets of the rejection process. We compared biopsies from ITx patients with no, mild, or moderate ACR by immunohistochemistry and quantitative PCR. Our results show that numbers of Paneth and stem cells remain constant in all study groups, whereas the transit-amplifying zone is the most impaired zone during ACR. We detected an unchanged level of antimicrobial peptides in Paneth cells and similar numbers of Ki-67 + IL-22R + stem cells revealing cell functionality in moderate ACR samples. We conclude that Paneth and stem cells are not primary target cells during ACR. IL-22R + Ki-67 + stem cells might be an interesting target cell population for protection and regeneration of the epithelial monolayer during/after a severe ACR in ITx patients. © 2017 The American Society of Transplantation and the American Society of Transplant Surgeons.

Neural Stem Cells Injected into the Sound-Damaged Cochlea Migrate Throughout the Cochlea and Express Markers of Hair Cells, Supporting Cells, and Spiral Ganglion Cells

PubMed Central

Corliss, Deborah A.; Gray, Brianna; Anderson, Julia K.; Bobbin, Richard P.; Snyder, Evan Y.; Cotanche, Douglas A.

2007-01-01

Most cases of hearing loss are caused by the death or dysfunction of one of the many cochlear cell types. We examined whether cells from a neural stem cell line could replace cochlear cell types lost after exposure to intense noise. For this purpose, we transplanted a clonal stem cell line into the scala tympani of sound damaged mice and guinea pigs. Utilizing morphological, protein expression and genetic criteria, stem cells were found with characteristics of both neural tissues (satellite, spiral ganglion and Schwann cells) and cells of the organ of Corti (hair cells, supporting cells). Additionally, noise-exposed, stem cell-injected animals exhibited a small but significant increase in the number of satellite cells and Type I spiral ganglion neurons compared to non-injected noise-exposed animals. These results indicate that cells of this neural stem cell line migrate from the scala tympani to Rosenthal's canal and the organ of Corti. Moreover, it suggests that cells of this neural stem cell line may derive some information needed from the microenvironment of the cochlea to differentiate into replacement cells in the cochlea. PMID:17659854

Manifestations and mechanisms of stem cell aging

PubMed Central

Liu, Ling

2011-01-01

Adult stem cells exist in most mammalian organs and tissues and are indispensable for normal tissue homeostasis and repair. In most tissues, there is an age-related decline in stem cell functionality but not a depletion of stem cells. Such functional changes reflect deleterious effects of age on the genome, epigenome, and proteome, some of which arise cell autonomously and others of which are imposed by an age-related change in the local milieu or systemic environment. Notably, some of the changes, particularly epigenomic and proteomic, are potentially reversible, and both environmental and genetic interventions can result in the rejuvenation of aged stem cells. Such findings have profound implications for the stem cell–based therapy of age-related diseases. PMID:21502357

Origins and implications of pluripotent stem cell variability and heterogeneity

PubMed Central

Cahan, Patrick; Daley, George Q.

2014-01-01

Pluripotent stem cells constitute a platform to model disease and developmental processes and can potentially be used in regenerative medicine. However, not all pluripotent cell lines are equal in their capacity to differentiate into desired cell types in vitro. Genetic and epigenetic variations contribute to functional variability between cell lines and heterogeneity within clones. These genetic and epigenetic variations could ‘lock’ the pluripotency network resulting in residual pluripotent cells or alter the signalling response of developmental pathways leading to lineage bias. The molecular contributors to functional variability and heterogeneity in both embryonic stem (ES) cells and induced pluripotent stem (iPS) cells are only beginning to emerge, yet they are crucial to the future of the stem cell field. PMID:23673969

Unraveling the non-senescence phenomenon in Hydra.

PubMed

Dańko, Maciej J; Kozłowski, Jan; Schaible, Ralf

2015-10-07

Unlike other metazoans, Hydra does not experience the distinctive rise in mortality with age known as senescence, which results from an increasing imbalance between cell damage and cell repair. We propose that the Hydra controls damage accumulation mainly through damage-dependent cell selection and cell sloughing. We examine our hypothesis with a model that combines cellular damage with stem cell renewal, differentiation, and elimination. The Hydra individual can be seen as a large single pool of three types of stem cells with some features of differentiated cells. This large stem cell community prevents "cellular damage drift," which is inevitable in complex conglomerate (differentiated) metazoans with numerous and generally isolated pools of stem cells. The process of cellular damage drift is based on changes in the distribution of damage among cells due to random events, and is thus similar to Muller's ratchet in asexual populations. Events in the model that are sources of randomness include budding, cellular death, and cellular damage and repair. Our results suggest that non-senescence is possible only in simple Hydra-like organisms which have a high proportion and number of stem cells, continuous cell divisions, an effective cell selection mechanism, and stem cells with the ability to undertake some roles of differentiated cells. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

Safeguarding Stem Cell-Based Regenerative Therapy against Iatrogenic Cancerogenesis: Transgenic Expression of DNASE1, DNASE1L3, DNASE2, DFFB Controlled By POLA1 Promoter in Proliferating and Directed Differentiation Resisting Human Autologous Pluripotent Induced Stem Cells Leads to their Death

PubMed Central

Malecki, Marek; LaVanne, Christine; Alhambra, Dominique; Dodivenaka, Chaitanya; Nagel, Sarah; Malecki, Raf

2014-01-01

Introduction The worst possible complication of using stem cells for regenerative therapy is iatrogenic cancerogenesis. The ultimate goal of our work is to develop a self-triggering feedback mechanism aimed at causing death of all stem cells, which resist directed differentiation, keep proliferating, and can grow into tumors. Specific aim The specific aim was threefold: (1) to genetically engineer the DNA constructs for the human, recombinant DNASE1, DNASE1L3, DNASE2, DFFB controlled by POLA promoter; (2) to bioengineer anti-SSEA-4 antibody guided vectors delivering transgenes to human undifferentiated and proliferating pluripotent stem cells; (3) to cause death of proliferating and directed differentiation resisting stem cells by transgenic expression of the human recombinant the DNases (hrDNases). Methods The DNA constructs for the human, recombinant DNASE1, DNASE1L3, DNASE2, DFFB controlled by POLA promoter were genetically engineered. The vectors targeting specifically SSEA-4 expressing stem cells were bioengineered. The healthy volunteers’ bone marrow mononuclear cells (BMMCs) were induced into human, autologous, pluripotent stem cells with non-integrating plasmids. Directed differentiation of the induced stem cells into endothelial cells was accomplished with EGF and BMP. The anti-SSEA 4 antibodies’ guided DNA vectors delivered the transgenes for the human recombinant DNases’ into proliferating stem cells. Results Differentiation of the pluripotent induced stem cells into the endothelial cells was verified by highlighting formation of tight and adherens junctions through transgenic expression of recombinant fluorescent fusion proteins: VE cadherin, claudin, zona occludens 1, and catenin. Proliferation of the stem cells was determined through highlighting transgenic expression of recombinant fluorescent proteins controlled by POLA promoter, while also reporting expression of the transgenes for the hrDNases. Expression of the transgenes for the DNases resulted in complete collapse of the chromatin architecture and degradation of the proliferating cells’ genomic DNA. The proliferating stem cells, but not the differentiating ones, were effectively induced to die. Conclusion Herein, we describe attaining the proof-of-concept for the strategy, whereby transgenic expression of the genetically engineered human recombinant DNases in proliferating and directed differentiation resisting stem cells leads to their death. This novel strategy reduces the risk of iatrogenic neoplasms in stem cell therapy. PMID:25045589

Cancer stem cells of the digestive system.

PubMed

Colvin, Hugh S; Nishida, Naohiro; Koseki, Jun; Konno, Masamitsu; Kawamoto, Koichi; Tsunekuni, Kenta; Doki, Yuichiro; Mori, Masaki; Ishii, Hideshi

2014-12-01

Stem cells of the digestive system are ideal in many ways for research, given they are abundant, highly proliferative and have a uniform structural arrangement. This in turn has enormously aided the research of cancer stem cells of the digestive system, which is now shaping our understanding of cancer stem cells. In this review, the recent advances in the understanding of cancer stem cells of the digestive system have been summarized, including aspects such as their identification, origin, cell-cycle dormancy, relationship with epithelial-mesenchymal transition, cellular metabolism and the underlying molecular mechanisms. Newly acquired knowledge concerning cancer stem cells have led to the development of novel cancer therapeutics with provisional yet encouraging results. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

The (not so) immortal strand hypothesis.

PubMed

Tomasetti, Cristian; Bozic, Ivana

2015-03-01

Non-random segregation of DNA strands during stem cell replication has been proposed as a mechanism to minimize accumulated genetic errors in stem cells of rapidly dividing tissues. According to this hypothesis, an "immortal" DNA strand is passed to the stem cell daughter and not the more differentiated cell, keeping the stem cell lineage replication error-free. After it was introduced, experimental evidence both in favor and against the hypothesis has been presented. Using a novel methodology that utilizes cancer sequencing data we are able to estimate the rate of accumulation of mutations in healthy stem cells of the colon, blood and head and neck tissues. We find that in these tissues mutations in stem cells accumulate at rates strikingly similar to those expected without the protection from the immortal strand mechanism. Utilizing an approach that is fundamentally different from previous efforts to confirm or refute the immortal strand hypothesis, we provide evidence against non-random segregation of DNA during stem cell replication. Our results strongly suggest that parental DNA is passed randomly to stem cell daughters and provides new insight into the mechanism of DNA replication in stem cells. Copyright © 2015. Published by Elsevier B.V.

The (not so) Immortal Strand Hypothesis

PubMed Central

Tomasetti, Cristian; Bozic, Ivana

2015-01-01

Background Non-random segregation of DNA strands during stem cell replication has been proposed as a mechanism to minimize accumulated genetic errors in stem cells of rapidly dividing tissues. According to this hypothesis, an “immortal” DNA strand is passed to the stem cell daughter and not the more differentiated cell, keeping the stem cell lineage replication error-free. After it was introduced, experimental evidence both in favor and against the hypothesis has been presented. Principal Findings Using a novel methodology that utilizes cancer sequencing data we are able to estimate the rate of accumulation of mutations in healthy stem cells of the colon, blood and head and neck tissues. We to find that in these tissues mutations in stem cells accumulate at rates strikingly similar to those expected without the protection from the immortal strand mechanism. Significance Utilizing an approach that is fundamentally different from previous efforts to confirm or refute the immortal strand hypothesis, we provide strong evidence against non-random segregation of DNA during stem cell replication. Our results strongly suggest that parental DNA is passed randomly to stem cell daughters and provides new insight into the mechanism of DNA replication in stem cells. PMID:25700960

Network-based expression analyses and experimental validations revealed high co-expression between Yap1 and stem cell markers compared to differentiated cells.

PubMed

Dehghanian, Fariba; Hojati, Zohreh; Esmaeili, Fariba; Masoudi-Nejad, Ali

2018-05-21

The Hippo signaling pathway is identified as a potential regulatory pathway which plays critical roles in differentiation and stem cell self-renewal. Yap1 is a primary transcriptional effector of this pathway. The importance of Yap1 in embryonic stem cells (ESCs) and differentiation procedure remains a challenging question, since two different observations have been reported. To answer this question we used co-expression network and differential co-expression analyses followed by experimental validations. Our results indicate that Yap1 is highly co-expressed with stem cell markers in ESCs but not in differentiated cells (DCs). The significant Yap1 down-regulation and also translocation of Yap1 into the cytoplasm during P19 differentiation was also detected. Moreover, our results suggest the E2f7, Lin28a and Dppa4 genes as possible regulatory nuclear factors of Hippo pathway in stem cells. The present findings are actively consistent with studies that suggested Yap1 as an essential factor for stem cell self-renewal. Copyright © 2018 Elsevier Inc. All rights reserved.

Health Span-Extending Activity of Human Amniotic Membrane- and Adipose Tissue-Derived Stem Cells in F344 Rats

PubMed Central

Kim, Dajeong; Kyung, Jangbeen; Park, Dongsun; Choi, Ehn-Kyoung; Kim, Kwang Sei; Shin, Kyungha; Lee, Hangyoung; Shin, Il Seob; Kang, Sung Keun

2015-01-01

Aging brings about the progressive decline in cognitive function and physical activity, along with losses of stem cell population and function. Although transplantation of muscle-derived stem/progenitor cells extended the health span and life span of progeria mice, such effects in normal animals were not confirmed. Human amniotic membrane-derived mesenchymal stem cells (AMMSCs) or adipose tissue-derived mesenchymal stem cells (ADMSCs) (1 × 106 cells per rat) were intravenously transplanted to 10-month-old male F344 rats once a month throughout their lives. Transplantation of AMMSCs and ADMSCs improved cognitive and physical functions of naturally aging rats, extending life span by 23.4% and 31.3%, respectively. The stem cell therapy increased the concentration of acetylcholine and recovered neurotrophic factors in the brain and muscles, leading to restoration of microtubule-associated protein 2, cholinergic and dopaminergic nervous systems, microvessels, muscle mass, and antioxidative capacity. The results indicate that repeated transplantation of AMMSCs and ADMSCs elongate both health span and life span, which could be a starting point for antiaging or rejuvenation effects of allogeneic or autologous stem cells with minimum immune rejection. Significance This study demonstrates that repeated treatment with stem cells in normal animals has antiaging potential, extending health span and life span. Because antiaging and prolonged life span are issues currently of interest, these results are significant for readers and investigators. PMID:26315571

Clinical-Grade Human Multipotent Adult Progenitor Cells Block CD8+ Cytotoxic T Lymphocytes

PubMed Central

Dekimpe, Emily; Van Woensel, Matthias; Roobrouck, Valerie D.; Bullens, Dominique M.; Pinxteren, Jef; Verfaillie, Catherine M.; Van Gool, Stefaan W.

2016-01-01

MultiStem cells are clinical-grade multipotent adult bone marrow-derived progenitor cells (MAPCs), with extensive replication potential and broader differentiation capacity compared with mesenchymal stem cells. Human MAPCs suppress T-cell proliferation induced by alloantigens and mutually interact with allogeneic natural killer cells. In this study, the interaction between MultiStem and CD8+ cytotoxic T lymphocytes (CTLs) was addressed for the first time. In an in vitro setting, the immunogenicity of MultiStem, the susceptibility of MultiStem toward CTL-mediated lysis, and its effects on CTL function were investigated. MultiStem was nonimmunogenic for alloreactive CTL induction and was—even after major histocompatibility complex class I upregulation—insensitive to alloantigen-specific CTL-mediated lysis. Furthermore, MultiStem reduced CTL proliferation and significantly decreased perforin expression during the T-cell activation phase. As a consequence, MultiStem dose-dependently impaired the induction of CTL function. These effects of MultiStem were mediated predominantly through contact-dependent mechanisms. Moreover, MultiStem cells considerably influenced the expression of T-cell activation markers CD25, CD69, and human leukocyte antigen-DR. The MultiStem-induced CD8−CD69+ T-cell population displayed a suppressive effect on the induction of CTL function during a subsequent mixed-lymphocyte culture. Finally, the killer activity of activated antigen-specific CTLs during their cytolytic effector phase was also diminished in the presence of MultiStem. This study confirms that these clinical-grade MAPCs are an immune-modulating population that inhibits CTL activation and effector responses and are, consequently, a highly valuable cell population for adoptive immunosuppressive therapy in diseases where damage is induced by CTLs. Significance Because multipotent adult progenitor cells (MAPCs) are among the noteworthy adult mesenchymal stem cell populations for immune therapy and have the advantage over mesenchymal stem cells (MSCs) of large-scale manufacturing and banking potential and thus prompt availability, it is important to understand how MAPCs interact with immune cells to validate their widespread therapeutic applicability. Cytotoxic immune effector cells play a crucial role in immune homeostasis and in the pathogenesis of some autoimmune diseases. This study assessed for the first time the in vitro influence of a clinical-grade human MAPC product (MultiStem) on the cytotoxic function of CD8+ T cells (CTLs) by evaluating the immunogenicity of MAPCs and the susceptibility of MAPCs toward CTL-mediated lysis and by analyzing the mechanism of MAPC-mediated modulation of CTL functionality. These results may represent a highly relevant contribution to the current knowledge and, in combination with the results of future phase II/III trials using MultiStem, could lead to an intriguing continuation of stem cell-based research for immunotherapy. PMID:27465071

Clinical-Grade Human Multipotent Adult Progenitor Cells Block CD8+ Cytotoxic T Lymphocytes.

PubMed

Plessers, Jeroen; Dekimpe, Emily; Van Woensel, Matthias; Roobrouck, Valerie D; Bullens, Dominique M; Pinxteren, Jef; Verfaillie, Catherine M; Van Gool, Stefaan W

2016-12-01

: MultiStem cells are clinical-grade multipotent adult bone marrow-derived progenitor cells (MAPCs), with extensive replication potential and broader differentiation capacity compared with mesenchymal stem cells. Human MAPCs suppress T-cell proliferation induced by alloantigens and mutually interact with allogeneic natural killer cells. In this study, the interaction between MultiStem and CD8 + cytotoxic T lymphocytes (CTLs) was addressed for the first time. In an in vitro setting, the immunogenicity of MultiStem, the susceptibility of MultiStem toward CTL-mediated lysis, and its effects on CTL function were investigated. MultiStem was nonimmunogenic for alloreactive CTL induction and was-even after major histocompatibility complex class I upregulation-insensitive to alloantigen-specific CTL-mediated lysis. Furthermore, MultiStem reduced CTL proliferation and significantly decreased perforin expression during the T-cell activation phase. As a consequence, MultiStem dose-dependently impaired the induction of CTL function. These effects of MultiStem were mediated predominantly through contact-dependent mechanisms. Moreover, MultiStem cells considerably influenced the expression of T-cell activation markers CD25, CD69, and human leukocyte antigen-DR. The MultiStem-induced CD8 - CD69 + T-cell population displayed a suppressive effect on the induction of CTL function during a subsequent mixed-lymphocyte culture. Finally, the killer activity of activated antigen-specific CTLs during their cytolytic effector phase was also diminished in the presence of MultiStem. This study confirms that these clinical-grade MAPCs are an immune-modulating population that inhibits CTL activation and effector responses and are, consequently, a highly valuable cell population for adoptive immunosuppressive therapy in diseases where damage is induced by CTLs. Because multipotent adult progenitor cells (MAPCs) are among the noteworthy adult mesenchymal stem cell populations for immune therapy and have the advantage over mesenchymal stem cells (MSCs) of large-scale manufacturing and banking potential and thus prompt availability, it is important to understand how MAPCs interact with immune cells to validate their widespread therapeutic applicability. Cytotoxic immune effector cells play a crucial role in immune homeostasis and in the pathogenesis of some autoimmune diseases. This study assessed for the first time the in vitro influence of a clinical-grade human MAPC product (MultiStem) on the cytotoxic function of CD8 + T cells (CTLs) by evaluating the immunogenicity of MAPCs and the susceptibility of MAPCs toward CTL-mediated lysis and by analyzing the mechanism of MAPC-mediated modulation of CTL functionality. These results may represent a highly relevant contribution to the current knowledge and, in combination with the results of future phase II/III trials using MultiStem, could lead to an intriguing continuation of stem cell-based research for immunotherapy. ©AlphaMed Press.

Feasibility of Cell Therapy in Multiple Sclerosis: A Systematic Review of 83 Studies

PubMed Central

Ardeshiry lajimi, Abdolreza; Hagh, Majid Farshdousti; Saki, Najmaldin; Mortaz, Esmaeil; Soleimani, Masoud; Rahim, Fakher

2013-01-01

Multiple Sclerosis is an inflammatory disease of the central nervous system in which T cells experience a second phase of activation, which ultimately leads to axonal demyelination and neurological disability. The recent advances in stem cell therapies may serve as potential treatments for neurological disorders. There are broad types of stem cells such as neural, embryonic, mesenchymal and hematopoietic stem cells with unprecedented hope in treating many debilitating diseases. In this paper we will review the substantial literature regarding experimental and clinical use of these stem cells and possible mechanisms in the treatment of MS. These results may pave the road for the utilization of stem cells for the treatment of MS. PMID:24505515

Isolation of hair follicle bulge stem cells from YFP-expressing reporter mice.

PubMed

Nakrieko, Kerry-Ann; Irvine, Timothy S; Dagnino, Lina

2013-01-01

In this article we provide a method to isolate hair follicle stem cells that have undergone targeted gene inactivation. The mice from which these cells are isolated are bred into a Rosa26-yellow fluorescent protein (YFP) reporter background, which results in YFP expression in the targeted stem cell population. These cells are isolated and purified by fluorescence-activated cell sorting, using epidermal stem cell-specific markers in conjunction with YFP fluorescence. The purified cells can be used for gene expression studies, clonogenic experiments, and biological assays, such as viability and capacity for directional migration.

Midbody Accumulation in Breast Cancer Stem Cells

DTIC Science & Technology

2011-08-01

transit amplifying or differentiating cells. These results suggest that MBds are in almost exclusively in stem cells and putative breast cancer stem...confer tumor-like properties to these cells. We were unable to establish GFP-MKLP1 breast cancer cell lines for this analysis for some reason that we...and nonpolarized cells (Fig. 1c, d). Immuno- electron microscopy confirmed this localization and revealed ultrastructural features characteristic of

Elucidating the identity and behavior of spermatogenic stem cells in the mouse testis.

PubMed

Yoshida, Shosei

2012-09-01

Spermatogenesis in mice and other mammalians is supported by a robust stem cell system. Stem cells maintain themselves and continue to produce progeny that will differentiate into sperm over a long period. The pioneering studies conducted from the 1950s to the 1970s, which were based largely on extensive morphological analyses, have established the fundamentals of mammalian spermatogenesis and its stem cells. The prevailing so-called A(single) (A(s)) model, which was originally established in 1971, proposes that singly isolated A(s) spermatogonia are in fact the stem cells. In 1994, the first functional stem cell assay was established based on the formation of repopulating colonies after transplantation in germ cell-depleted host testes, which substantially accelerated the understanding of spermatogenic stem cells. However, because testicular tissues are dissociated into single-cell suspension before transplantation, it was impossible to evaluate the A(s) and other classical models solely by this technique. From 2007 onwards, functional assessment of stem cells without destroying the tissue architecture has become feasible by means of pulse-labeling and live-imaging strategies. Results obtained from these experiments have been challenging the classical thought of stem cells, in which stem cells are a limited number of specialized cells undergoing asymmetric division to produce one self-renewing and one differentiating daughter cells. In contrast, the emerging data suggest that an extended and heterogeneous population of cells exhibiting different degrees of self-renewing and differentiating probabilities forms a reversible, flexible, and stochastic stem cell system as a population. These features may lead to establishment of a more universal principle on stem cells that is shared by other systems.

Quality Assurance in Stem Cell Banking: Emphasis on Embryonic and Induced Pluripotent Stem Cell Banking.

PubMed

Kallur, Therése; Blomberg, Pontus; Stenfelt, Sonya; Tryggvason, Kristian; Hovatta, Outi

2017-01-01

For quality assurance (QA) in stem cell banking, a planned system is needed to ensure that the banked products, stem cells, meet the standards required for research, clinical use, and commercial biotechnological applications. QA is process oriented, avoids, or minimizes unacceptable product defects, and particularly encompasses the management and operational systems of the bank, as well as the ethical and legal frameworks. Quality control (QC ) is product oriented and therefore ensures the stem cells of a bank are what they are expected to be. Testing is for controlling, not assuring, product quality, and is therefore a part of QC , not QA. Like QA, QC is essential for banking cells for quality research and translational application (Schwartz et al., Lancet 379:713-720, 2012). Human embryonic stem cells (hESCs), as cells derived from donated supernumerary embryos from in vitro fertilization (IVF) therapy, are different from other stem cell types in resulting from an embryo that has had two donors . This imposes important ethical and legal constraints on the utility of the cells, which, together with quite specific culture conditions, require special attention in the QA system. Importantly, although the origin and derivation of induced pluripotent stem cells (iPSCs ) differ from that of hESCs, many of the principles of QA for hESC banking are applicable to iPSC banking (Stacey et al., Cell Stem Cell 13:385-388, 2013). Furthermore, despite differences between the legal and regulatory frameworks for hESC and iPSC banking between different countries, the requirements for QA are being harmonized (Stacey et al., Cell Stem Cell 13:385-388, 2013; International Stem Cell Banking Initiative, Stem Cell Rev 5:301-314, 2009).

Chromosome microduplication in somatic cells decreases the genetic stability of human reprogrammed somatic cells and results in pluripotent stem cells.

PubMed

Yu, Yang; Chang, Liang; Zhao, Hongcui; Li, Rong; Fan, Yong; Qiao, Jie

2015-05-12

Human pluripotent stem cells, including cloned embryonic and induced pluripotent stem cells, offer a limitless cellular source for regenerative medicine. However, their derivation efficiency is limited, and a large proportion of cells are arrested during reprogramming. In the current study, we explored chromosome microdeletion/duplication in arrested and established reprogrammed cells. Our results show that aneuploidy induced by somatic cell nuclear transfer technology is a key factor in the developmental failure of cloned human embryos and primary colonies from implanted cloned blastocysts and that expression patterns of apoptosis-related genes are dynamically altered. Overall, ~20%-53% of arrested primary colonies in induced plurpotent stem cells displayed aneuploidy, and upregulation of P53 and Bax occurred in all arrested primary colonies. Interestingly, when somatic cells with pre-existing chromosomal mutations were used as donor cells, no cloned blastocysts were obtained, and additional chromosomal mutations were detected in the resulting iPS cells following long-term culture, which was not observed in the two iPS cell lines with normal karyotypes. In conclusion, aneuploidy induced by the reprogramming process restricts the derivation of pluripotent stem cells, and, more importantly, pre-existing chromosomal mutations enhance the risk of genome instability, which limits the clinical utility of these cells.

Tumor stem cells: A new approach for tumor therapy (Review)

PubMed Central

MENG, MIN; ZHAO, XIN-HAN; NING, QIAN; HOU, LEI; XIN, GUO-HONG; LIU, LI-FENG

2012-01-01

Recent studies have demonstrated the existence of a minority of tumor cells possessing the stem cell properties of self-renewal and differentiation in leukemia and several solid tumors. However, these cells do not possess the normal regulatory mechanisms of stem cells. Following transplantation, they are capable of initiating tumorigenesis and are therefore known as ‘tumor stem cells’. Cellular origin analysis of tumor stem cells has resulted in three hypotheses: Embryonal rest hypothesis, anaplasia and maturation arrest. Several signaling pathways which are involved in carcinogenesis, including Wnt/β-catenin, Notch and Oct-4 signaling pathways are crucial in normal stem cell self-renewal decisions, suggesting that breakdown in the regulation of self-renewal may be a key event in the development of tumors. Thus, tumors can be regarded as an abnormal organ in which stem cells have escaped from the normal constraints on self-renewal, thus, leading to abnormally differentiated tumor cells that lose the ability to form tumors. This new model for maligancies has significance for clinical research and treatment. PMID:22844351

Cellular and epigenetic drivers of stem cell ageing.

PubMed

Ermolaeva, Maria; Neri, Francesco; Ori, Alessandro; Rudolph, K Lenhard

2018-06-01

Adult tissue stem cells have a pivotal role in tissue maintenance and regeneration throughout the lifespan of multicellular organisms. Loss of tissue homeostasis during post-reproductive lifespan is caused, at least in part, by a decline in stem cell function and is associated with an increased incidence of diseases. Hallmarks of ageing include the accumulation of molecular damage, failure of quality control systems, metabolic changes and alterations in epigenome stability. In this Review, we discuss recent evidence in support of a novel concept whereby cell-intrinsic damage that accumulates during ageing and cell-extrinsic changes in ageing stem cell niches and the blood result in modifications of the stem cell epigenome. These cumulative epigenetic alterations in stem cells might be the cause of the deregulation of developmental pathways seen during ageing. In turn, they could confer a selective advantage to mutant and epigenetically drifted stem cells with altered self-renewal and functions, which contribute to the development of ageing-associated organ dysfunction and disease.

Stem Cell Therapy for the Central Nervous System in Lysosomal Storage Diseases.

PubMed

Siddiqi, Faez; Wolfe, John H

2016-10-01

Neurological diseases with genetic etiologies result in the loss or dysfunction of neural cells throughout the CNS. At present, few treatment options exist for the majority of neurogenetic diseases. Stem cell transplantation (SCT) into the CNS has the potential to be an effective treatment modality because progenitor cells may replace lost cells in the diseased brain, provide multiple trophic factors, or deliver missing proteins. This review focuses on the use of SCT in lysosomal storage diseases (LSDs), a large group of monogenic disorders with prominent CNS disease. In most patients the CNS disease results in intellectual disability that is refractory to current standard-of-care treatment. A large amount of preclinical work on brain-directed SCT has been performed in rodent LSD models. Cell types that have been used for direct delivery into the CNS include neural stem cells, embryonic and induced pluripotent stem cells, and mesenchymal stem cells. Hematopoietic stem cells have been an effective therapy for the CNS in a few LSDs and may be augmented by overexpression of the missing gene. Current barriers and potential strategies to improve SCT for translation into effective patient therapies are discussed.

MiR-7 inhibited peripheral nerve injury repair by affecting neural stem cells migration and proliferation through cdc42.

PubMed

Zhou, Nan; Hao, Shuang; Huang, Zongqiang; Wang, Weiwei; Yan, Penghui; Zhou, Wei; Zhu, Qihang; Liu, Xiaokang

2018-01-01

Objective Neural stem cells play an important role in the recovery and regeneration of peripheral nerve injury, and the microRNA-7 (miR-7) regulates differentiation of neural stem cells. This study aimed to explore the role of miR-7 in neural stem cells homing and proliferation and its influence on peripheral nerve injury repair. Methods The mice model of peripheral nerve injury was created by segmental sciatic nerve defect (sciatic nerve injury), and neural stem cells treatment was performed with a gelatin hydrogel conduit containing neural stem cells inserted into the sciatic nerve injury mice. The Sciatic Function Index was used to quantify sciatic nerve functional recovery in the mice. The messenger RNA and protein expression were detected by reverse transcription polymerase chain reaction and Western blot, respectively. Luciferase reporter assay was used to confirm the binding between miR-7 and the 3'UTR of cell division cycle protein 42 (cdc42). The neural stem cells migration and proliferation were analyzed by transwell assay and a Cell-LightTM EdU DNA Cell Proliferation kit, respectively. Results Neural stem cells treatment significantly promoted nerve repair in sciatic nerve injury mice. MiR-7 expression was decreased in sciatic nerve injury mice with neural stem cells treatment, and miR-7 mimic transfected into neural stem cells suppressed migration and proliferation, while miR-7 inhibitor promoted migration and proliferation. The expression level and effect of cdc42 on neural stem cells migration and proliferation were opposite to miR-7, and the luciferase reporter assay proved that cdc42 was a target of miR-7. Using co-transfection into neural stem cells, we found pcDNA3.1-cdc42 and si-cdc42 could reverse respectively the role of miR-7 mimic and miR-7 inhibitor on neural stem cells migration and proliferation. In addition, miR-7 mimic-transfected neural stem cells could abolish the protective role of neural stem cells on peripheral nerve injury. Conclusion MiR-7 inhibited peripheral nerve injury repair by affecting neural stem cells migration and proliferation through cdc42.

Isolation, characterization, and differentiation of stem cells for cartilage regeneration.

PubMed

Beane, Olivia S; Darling, Eric M

2012-10-01

The goal of tissue engineering is to create a functional replacement for tissues damaged by injury or disease. In many cases, impaired tissues cannot provide viable cells, leading to the investigation of stem cells as a possible alternative. Cartilage, in particular, may benefit from the use of stem cells since the tissue has low cellularity and cannot effectively repair itself. To address this need, researchers are investigating the chondrogenic capabilities of several multipotent stem cell sources, including adult and extra-embryonic mesenchymal stem cells (MSCs), embryonic stem cells (ESCs), and induced pluripotent stem cells (iPSCs). Comparative studies indicate that each cell type has advantages and disadvantages, and while direct comparisons are difficult to make, published data suggest some sources may be more promising for cartilage regeneration than others. In this review, we identify current approaches for isolating and chondrogenically differentiating MSCs from bone marrow, fat, synovium, muscle, and peripheral blood, as well as cells from extra-embryonic tissues, ESCs, and iPSCs. Additionally, we assess chondrogenic induction with growth factors, identifying standard cocktails used for each stem cell type. Cell-only (pellet) and scaffold-based studies are also included, as is a discussion of in vivo results.

Stem cell plasticity.

PubMed

Lakshmipathy, Uma; Verfaillie, Catherine

2005-01-01

The central dogma in stem cell biology has been that cells isolated from a particular tissue can renew and differentiate into lineages of the tissue it resides in. Several studies have challenged this idea by demonstrating that tissue specific cell have considerable plasticity and can cross-lineage restriction boundary and give rise to cell types of other lineages. However, the lack of a clear definition for plasticity has led to confusion with several reports failing to demonstrate that a single cell can indeed differentiate into multiple lineages at significant levels. Further, differences between results obtained in different labs has cast doubt on some results and several studies still await independent confirmation. In this review, we critically evaluate studies that report stem cell plasticity using three rigid criteria to define stem cell plasticity; differentiation of a single cell into multiple cell lineages, functionality of differentiated cells in vitro and in vivo, robust and persistent engraft of transplanted cells.

Comparison of stem morphology and anatomy of two alfalfa clonal lines exhibiting divergent cell wall composition.

PubMed

Gronwald, John W; Bucciarelli, Bruna

2013-08-30

In previous research, two alfalfa clonal lines (252 and 1283) were identified that exhibited environmentally stable differences in stem cell walls. Compared with stems of 1283, stems of 252 have a higher cell wall concentration and greater amounts of lignin and cellulose but reduced levels of pectic sugar residues. These results suggest greater deposition of secondary xylem and a reduction in pith in stems of 252 compared with 1283. The stem morphology and anatomy of first-cut and second-cut harvests of field-grown 1283 and 252 were examined. For both harvests, stems of 1283 were thicker and had a higher leaf/stem ratio compared with stems of 252. Stem cross-sections of both genotypes were stained for lignin, and the proportions of stem area that were pith and secondary xylem were measured using ImageJ. Stems of 252 exhibited greater deposition of secondary xylem and a reduction in pith proportion compared with stems of 1283 for the first-cut harvest, but this difference was not statistically significant for the second-cut harvest. The results indicate that the proportions of secondary xylem and pith are not environmentally stable in these two genotypes and hence cannot be the sole basis for the differences in cell wall concentration/composition. © 2012 Society of Chemical Industry.

Acute myeloid leukemia originates from a hierarchy of leukemic stem cell classes that differ in self-renewal capacity.

PubMed

Hope, Kristin J; Jin, Liqing; Dick, John E

2004-07-01

Emerging evidence suggests cancer stem cells sustain neoplasms; however, little is understood of the normal cell initially targeted and the resultant cancer stem cells. We show here, by tracking individual human leukemia stem cells (LSCs) in nonobese diabetic-severe combined immunodeficiency mice serially transplanted with acute myeloid leukemia cells, that LSCs are not functionally homogeneous but, like the normal hematopoietic stem cell (HSC) compartment, comprise distinct hierarchically arranged LSC classes. Distinct LSC fates derived from heterogeneous self-renewal potential. Some LSCs emerged only in recipients of serial transplantation, indicating they divided rarely and underwent self-renewal rather than commitment after cell division within primary recipients. Heterogeneity in LSC self-renewal potential supports the hypothesis that they derive from normal HSCs. Furthermore, normal developmental processes are not completely abolished during leukemogenesis. The existence of multiple stem cell classes shows the need for LSC-targeted therapies.

SU-E-I-39: Molecular Image Guided Cancer Stem Cells Therapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Abdollahi, H

Purpose: Cancer stem cells resistance to radiation is a problematic issue that has caused a big fail in cancer treatment. Methods: As a primary work, molecular imaging can indicate the main mechanisms of radiation resistance of cancer stem cells. By developing and commissioning new probes and nanomolecules and biomarkers, radiation scientist will able to identify the essential pathways of radiation resistance of cancer stem cells. As the second solution, molecular imaging is a best way to find biological target volume and delineate cancer stem cell tissues. In the other hand, by molecular imaging techniques one can image the treatment responsemore » in tumor and also in normal tissue. In this issue, the response of cancer stem cells to radiation during therapy course can be imaged, also the main mechanisms of radiation resistance and finding the best radiation modifiers (sensitizers) can be achieved by molecular imaging modalities. In adaptive radiotherapy the molecular imaging plays a vital role to have higher tumor control probability by delivering high radiation doses to cancer stem cells in any time of treatment. The outcome of a feasible treatment is dependent to high cancer stem cells response to radiation and removing all of which, so a good imaging modality can show this issue and preventing of tumor recurrence and metastasis. Results: Our results are dependent to use of molecular imaging as a new modality in the clinic. We propose molecular imaging as a new radiobiological technique to solve radiation therapy problems due to cancer stem cells. Conclusion: Molecular imaging guided cancer stem cell diagnosis and therapy is a new approach in the field of cancer treatment. This new radiobiological imaging technique should be developed in all clinics as a feasible tool that is more biological than physical imaging.« less

s-SHIP expression identifies a subset of murine basal prostate cells as neonatal stem cells

PubMed Central

Brocqueville, Guillaume; Chmelar, Renee S.; Bauderlique-Le Roy, Hélène; Deruy, Emeric; Tian, Lu; Vessella, Robert L.; Greenberg, Norman M.; Bourette, Roland P.

2016-01-01

Isolation of prostate stem cells (PSCs) is crucial for understanding their biology during normal development and tumorigenesis. In this aim, we used a transgenic mouse model expressing GFP from the stem cell-specific s-SHIP promoter to mark putative stem cells during postnatal prostate development. Here we show that cells identified by GFP expression are present transiently during early prostate development and localize to the basal cell layer of the epithelium. These prostate GFP+ cells are a subpopulation of the Lin− CD24+ Sca-1+ CD49f+ cells and are capable of self-renewal together with enhanced growth potential in sphere-forming assay in vitro, a phenotype consistent with that of a PSC population. Transplantation assays of prostate GFP+ cells demonstrate reconstitution of prostate ducts containing both basal and luminal cells in renal grafts. Altogether, these results demonstrate that s-SHIP promoter expression is a new marker for neonatal basal prostate cells exhibiting stem cell properties that enables PSCs in situ identification and isolation via a single consistent parameter. Transcriptional profiling of these GFP+ neonatal stem cells showed an increased expression of several components of the Wnt signaling pathway. It also identified stem cell regulators with potential applications for further analyses of normal and cancer stem cells. PMID:27081082

Enhancer of polycomb coordinates multiple signaling pathways to promote both cyst and germline stem cell differentiation in the Drosophila adult testis

PubMed Central

Feng, Lijuan; Shi, Zhen; Chen, Xin

2017-01-01

Stem cells reside in a particular microenvironment known as a niche. The interaction between extrinsic cues originating from the niche and intrinsic factors in stem cells determines their identity and activity. Maintenance of stem cell identity and stem cell self-renewal are known to be controlled by chromatin factors. Herein, we use the Drosophila adult testis which has two adult stem cell lineages, the germline stem cell (GSC) lineage and the cyst stem cell (CySC) lineage, to study how chromatin factors regulate stem cell differentiation. We find that the chromatin factor Enhancer of Polycomb [E(Pc)] acts in the CySC lineage to negatively control transcription of genes associated with multiple signaling pathways, including JAK-STAT and EGF, to promote cellular differentiation in the CySC lineage. E(Pc) also has a non-cell-autonomous role in regulating GSC lineage differentiation. When E(Pc) is specifically inactivated in the CySC lineage, defects occur in both germ cell differentiation and maintenance of germline identity. Furthermore, compromising Tip60 histone acetyltransferase activity in the CySC lineage recapitulates loss-of-function phenotypes of E(Pc), suggesting that Tip60 and E(Pc) act together, consistent with published biochemical data. In summary, our results demonstrate that E(Pc) plays a central role in coordinating differentiation between the two adult stem cell lineages in Drosophila testes. PMID:28196077

mir-300 promotes self-renewal and inhibits the differentiation of glioma stem-like cells.

PubMed

Zhang, Daming; Yang, Guang; Chen, Xin; Li, Chunmei; Wang, Lu; Liu, Yaohua; Han, Dayong; Liu, Huailei; Hou, Xu; Zhang, Weiguang; Li, Chenguang; Han, Zhanqiang; Gao, Xin; Zhao, Shiguang

2014-08-01

MicroRNAs (miRNAs) are small noncoding RNAs that have been critically implicated in several human cancers. miRNAs are thought to participate in various biological processes, including proliferation, cell cycle, apoptosis, and even the regulation of the stemness properties of cancer stem cells. In this study, we explore the potential role of miR-300 in glioma stem-like cells (GSLCs). We isolated GSLCs from glioma biopsy specimens and identified the stemness properties of the cells through neurosphere formation assays, multilineage differentiation ability analysis, and immunofluorescence analysis of glioma stem cell markers. We found that miR-300 is commonly upregulated in glioma tissues, and the expression of miR-300 was higher in GSLCs. The results of functional experiments demonstrated that miR-300 can enhance the self-renewal of GSLCs and reduce differentiation toward both astrocyte and neural fates. In addition, LZTS2 is a direct target of miR-300. In conclusion, our results demonstrate the critical role of miR-300 in GSLCs and its functions in LZTS2 inhibition and describe a new approach for the molecular regulation of tumor stem cells.

Delayed animal aging through the recovery of stem cell senescence by platelet rich plasma.

PubMed

Liu, Hen-Yu; Huang, Chiung-Fang; Lin, Tzu-Chieh; Tsai, Ching-Yu; Tina Chen, Szu-Yu; Liu, Alice; Chen, Wei-Hong; Wei, Hong-Jian; Wang, Ming-Fu; Williams, David F; Deng, Win-Ping

2014-12-01

Aging is related to loss of functional stem cell accompanying loss of tissue and organ regeneration potentials. Previously, we demonstrated that the life span of ovariectomy-senescence accelerated mice (OVX-SAMP8) was significantly prolonged and similar to that of the congenic senescence-resistant strain of mice after platelet rich plasma (PRP)/embryonic fibroblast transplantation. The aim of this study is to investigate the potential of PRP for recovering cellular potential from senescence and then delaying animal aging. We first examined whether stem cells would be senescent in aged mice compared to young mice. Primary adipose derived stem cells (ADSCs) and bone marrow derived stem cells (BMSCs) were harvested from young and aged mice, and found that cell senescence was strongly correlated to animal aging. Subsequently, we demonstrated that PRP could recover cell potential from senescence, such as promote cell growth (cell proliferation and colony formation), increase osteogenesis, decrease adipogenesis, restore cell senescence related markers and resist the oxidative stress in stem cells from aged mice. The results also showed that PRP treatment in aged mice could delay mice aging as indicated by survival, body weight and aging phenotypes (behavior and gross morphology) in term of recovering the cellular potential of their stem cells compared to the results on aged control mice. In conclusion these findings showed that PRP has potential to delay aging through the recovery of stem cell senescence and could be used as an alternative medicine for tissue regeneration and future rejuvenation. Copyright © 2014 Elsevier Ltd. All rights reserved.

A modified efficient method for dental pulp stem cell isolation.

PubMed

Raoof, Maryam; Yaghoobi, Mohammad Mehdi; Derakhshani, Ali; Kamal-Abadi, Ali Mohammadi; Ebrahimi, Behnam; Abbasnejad, Mehdi; Shokouhinejad, Noushin

2014-03-01

Dental pulp stem cells can be used in regenerative endodontic therapy. The aim of this study was to introduce an efficient method for dental pulp stem cells isolation. In this in-vitro study, 60 extracted human third molars were split and pulp tissue was extracted. Dental pulp stem cells were isolated by the following three different methods: (1) digestion of pulp by collagenase/dispase enzyme and culture of the released cells; (2) outgrowth of the cells by culture of undigested pulp pieces; (3) digestion of pulp tissue pieces and fixing them. The cells were cultured in minimum essential medium alpha modification (αMEM) medium supplemented with 20% fetal bovine serum(FBS) in humid 37°C incubator with 5% CO 2. The markers of stem cells were studied by reverse transcriptase polymerase chain reaction (PCR). The student t-test was used for comparing the means of independent groups. P <0.05 was considered as significant. The results indicated that by the first method a few cell colonies with homogenous morphology were detectable after 4 days, while in the outgrowth method more time was needed (10-12 days) to allow sufficient numbers of heterogeneous phenotype stem cells to migrate out of tissue. Interestingly, with the improved third method, we obtained stem cells successfully with about 60% efficiency after 2 days. The results of RT-PCR suggested the expression of Nanog, Oct-4, and Nucleostemin markers in the isolated cells from dental pulps. This study proposes a new method with high efficacy to obtain dental pulp stem cells in a short time.

Stem cell banking: between traceability and identifiability

PubMed Central

2010-01-01

Stem cell banks are increasingly seen as an essential resource of biological materials for both basic and translational research. Stem cell banks support transnational access to quality-controlled and ethically sourced stem cell lines from different origins and of varying grades. According to the Organisation for Economic Co-operation and Development, advances in regenerative medicine are leading to the development of a bioeconomy, 'a world where biotechnology contributes to a significant share of economic output'. Consequently, stem cell banks are destined to constitute a pillar of the bioeconomy in many countries. While certain ethical and legal concerns are specific to the nature of stem cells, stem cell banking could do well to examine the approaches fostered by tissue banking generally. Indeed, the past decade has seen a move to simplify and harmonize biological tissue and data banking so as to foster international interoperability. In particular, the issues of consent and of traceability illustrate not only commonalities but the opportunity for stem cell banking to appreciate the lessons learned in biobanking generally. This paper analyzes convergence and divergence in issues surrounding policy harmonization, transnational sharing, informed consent, traceability and return of results in the context of stem cell banks. PMID:20923580

Therapeutic application of stem cells in gastroenterology: An up-date

PubMed Central

Burra, Patrizia; Bizzaro, Debora; Ciccocioppo, Rachele; Marra, Fabio; Piscaglia, Anna Chiara; Porretti, Laura; Gasbarrini, Antonio; Russo, Francesco Paolo

2011-01-01

Adult stem cells represent the self-renewing progenitors of numerous body tissues, and they are currently classified according to their origin and differentiation ability. In recent years, the research on stem cells has expanded enormously and holds therapeutic promises for many patients suffering from currently disabling diseases. This paper focuses on the possible use of stem cells in the two main clinical settings in gastroenterology, i.e., hepatic and intestinal diseases, which have a strong impact on public health worldwide. Despite encouraging results obtained in both regenerative medicine and immune-mediated conditions, further studies are needed to fully understand the biology of stem cells and carefully assess their putative oncogenic properties. Moreover, the research on stem cells arouses fervent ethical, social and political debate. The Italian Society of Gastroenterology sponsored a workshop on stem cells held in Verona during the XVI Congress of the Federation of Italian Societies of Digestive Diseases (March 6-9, 2010). Here, we report on the issues discussed, including liver and intestinal diseases that may benefit from stem cell therapy, the biology of hepatic and intestinal tissue repair, and stem cell usage in clinical trials. PMID:22025875

Potential of human dental stem cells in repairing the complete transection of rat spinal cord

NASA Astrophysics Data System (ADS)

Yang, Chao; Li, Xinghan; Sun, Liang; Guo, Weihua; Tian, Weidong

2017-04-01

Objective. The adult spinal cord of mammals contains a certain amount of neural precursor cells, but these endogenous cells have a limited capacity for replacement of lost cells after spinal cord injury. The exogenous stem cells transplantation has become a therapeutic strategy for spinal cord repairing because of their immunomodulatory and differentiation capacity. In addition, dental stem cells originating from the cranial neural crest might be candidate cell sources for neural engineering. Approach. Human dental follicle stem cells (DFSCs), stem cells from apical papilla (SCAPs) and dental pulp stem cells (DPSCs) were isolated and identified in vitro, then green GFP-labeled stem cells with pellets were transplanted into completely transected spinal cord. The functional recovery of rats and multiple neuro-regenerative mechanisms were explored. Main results. The dental stem cells, especially DFSCs, demonstrated the potential in repairing the completely transected spinal cord and promote functional recovery after injury. The major involved mechanisms were speculated below: First, dental stem cells inhibited the expression of interleukin-1β to reduce the inflammatory response; second, they inhibited the expression of ras homolog gene family member A (RhoA) to promote neurite regeneration; third, they inhibited the sulfonylurea receptor1 (SUR-1) expression to reduce progressive hemorrhagic necrosis; lastly, parts of the transplanted cells survived and differentiated into mature neurons and oligodendrocytes but not astrocyte, which is beneficial for promoting axons growth. Significance. Dental stem cells presented remarkable tissue regenerative capability after spinal cord injury through immunomodulatory, differentiation and protection capacity.

Links between DNA Replication, Stem Cells and Cancer

PubMed Central

Vassilev, Alex; DePamphilis, Melvin L.

2017-01-01

Cancers can be categorized into two groups: those whose frequency increases with age, and those resulting from errors during mammalian development. The first group is linked to DNA replication through the accumulation of genetic mutations that occur during proliferation of developmentally acquired stem cells that give rise to and maintain tissues and organs. These mutations, which result from DNA replication errors as well as environmental insults, fall into two categories; cancer driver mutations that initiate carcinogenesis and genome destabilizing mutations that promote aneuploidy through excess genome duplication and chromatid missegregation. Increased genome instability results in accelerated clonal evolution leading to the appearance of more aggressive clones with increased drug resistance. The second group of cancers, termed germ cell neoplasia, results from the mislocation of pluripotent stem cells during early development. During normal development, pluripotent stem cells that originate in early embryos give rise to all of the cell lineages in the embryo and adult, but when they mislocate to ectopic sites, they produce tumors. Remarkably, pluripotent stem cells, like many cancer cells, depend on the Geminin protein to prevent excess DNA replication from triggering DNA damage-dependent apoptosis. This link between the control of DNA replication during early development and germ cell neoplasia reveals Geminin as a potential chemotherapeutic target in the eradication of cancer progenitor cells. PMID:28125050

Responsible Translation of Stem Cell Research: An Assessment of Clinical Trial Registration and Publications.

PubMed

Fung, Moses; Yuan, Yan; Atkins, Harold; Shi, Qian; Bubela, Tania

2017-05-09

We assessed the extent to which the publication of clinical trial results of innovative cell-based interventions reflects International Society for Stem Cell Research best practice guidelines. We assessed: (1) characteristics and time to publication of completed trials; (2) quality of reported trials; and (3) results of published trials. We identified and analyzed publications from 1,052 novel stem cell clinical trials: 179 (45.4%) of 393 completed trials had published results; 48 trials were registered by known stem cell tourism clinics, none of which reported results. Completed non-industry-sponsored trials initially published more rapidly, but differences with industry-sponsored trials decreased over time. Most publications reported safety, and 67.3% (mainly early-stage trials) reported positive outcomes. A higher proportion of industry trials reported positive efficacy. Heightened patient expectations for stem cell therapies give rise to ethical obligations for the transparent conduct of clinical trials. Reporting guidelines need to be developed that are specific to early-phase clinical trials. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

CD133 Is Not Suitable Marker for Isolating Melanoma Stem Cells from D10 Cell Line

PubMed Central

Rajabi Fomeshi, Motahareh; Ebrahimi, Marzieh; Mowla, Seyed Javad; Firouzi, Javad; Khosravani, Pardis

2016-01-01

Objective Cutaneous melanoma is the most hazardous malignancy of skin cancer with a high mortality rate. It has been reported that cancer stem cells (CSCs) are responsible for malignancy in most of cancers including melanoma. The aim of this study is to compare two common methods for melanoma stem cell enriching; isolating based on the CD133 cell surface marker and spheroid cell culture. Materials and Methods In this experimental study, melanoma stem cells were enriched by fluorescence activated cell sorting (FACS) based on the CD133 protein expression and spheroid culture of D10 melanoma cell line,. To determine stemness features, the mRNA expression analysis of ABCG2, c-MYC, NESTIN, OCT4-A and -B genes as well as colony and spheroid formation assays were utilized in unsorted CD133+, CD133- and spheroid cells. Significant differences of the two experimental groups were compared using student’s t tests and a two-tailed value of P<0.05 was statistically considered as a significant threshold. Results Our results demonstrated that spheroid cells had more colony and spheroid forming ability, rather than CD133+ cells and the other groups. Moreover, melanospheres expressed higher mRNA expression level of ABCG2, c-MYC, NESTIN and OCT4-A com- pared to other groups (P<0.05). Conclusion Although CD133+ derived melanoma cells represented stemness fea- tures, our findings demonstrated that spheroid culture could be more effective meth- od to enrich melanoma stem cells. PMID:27054115

Understanding the role of growth factors in modulating stem cell tenogenesis.

PubMed

Gonçalves, Ana I; Rodrigues, Márcia T; Lee, Sang-Jin; Atala, Anthony; Yoo, James J; Reis, Rui L; Gomes, Manuela E

2013-01-01

Current treatments for tendon injuries often fail to fully restore joint biomechanics leading to the recurrence of symptoms, and thus resulting in a significant health problem with a relevant social impact worldwide. Cell-based approaches involving the use of stem cells might enable tailoring a successful tendon regeneration outcome. As growth factors (GFs) powerfully regulate the cell biological response, their exogenous addition can further stimulate stem cells into the tenogenic lineage, which might eventually depend on stem cells source. In the present study we investigate the tenogenic differentiation potential of human- amniotic fluid stem cells (hAFSCs) and adipose-derived stem cells (hASCs) with several GFs associated to tendon development and healing; namely, EGF, bFGF, PDGF-BB and TGF-β1. Stem cells response to biochemical stimuli was studied by screening of tendon-related genes (collagen type I, III, decorin, tenascin C and scleraxis) and proteins found in tendon extracellular matrix (ECM) (Collagen I, III, and Tenascin C). Despite the fact that GFs did not seem to influence the synthesis of tendon ECM proteins, EGF and bFGF influenced the expression of tendon-related genes in hAFSCs, while EGF and PDGF-BB stimulated the genetic expression in hASCs. Overall results on cellular alignment morphology, immunolocalization and PCR analysis indicated that both stem cell source can be biochemically induced towards tenogenic commitment, validating the potential of hASCs and hAFSCs for tendon regeneration strategies.

Cell fiber-based three-dimensional culture system for highly efficient expansion of human induced pluripotent stem cells.

PubMed

Ikeda, Kazuhiro; Nagata, Shogo; Okitsu, Teru; Takeuchi, Shoji

2017-06-06

Human pluripotent stem cells are a potentially powerful cellular resource for application in regenerative medicine. Because such applications require large numbers of human pluripotent stem cell-derived cells, a scalable culture system of human pluripotent stem cell needs to be developed. Several suspension culture systems for human pluripotent stem cell expansion exist; however, it is difficult to control the thickness of cell aggregations in these systems, leading to increased cell death likely caused by limited diffusion of gases and nutrients into the aggregations. Here, we describe a scalable culture system using the cell fiber technology for the expansion of human induced pluripotent stem (iPS) cells. The cells were encapsulated and cultured within the core region of core-shell hydrogel microfibers, resulting in the formation of rod-shaped or fiber-shaped cell aggregations with sustained thickness and high viability. By encapsulating the cells with type I collagen, we demonstrated a long-term culture of the cells by serial passaging at a high expansion rate (14-fold in four days) while retaining its pluripotency. Therefore, our culture system could be used for large-scale expansion of human pluripotent stem cells for use in regenerative medicine.

Differentiation and characteristics of the enhanced green fluorescent protein gene transgenic goat neural stem cells cultured in attached and non-attached plates.

PubMed

Zheng, Yue-Mao; Dang, Yong-Hui; Qiu, Shuang; Qi, Ying-Pei; Xu, Yong-Ping; Sai, Wu-Jia-Fu

2011-08-01

The aims of this study were (i) to determine whether NSCs (neural stem cells) could be isolated from the brain of embryonic day 98 fetal goat, (ii) to determine if these stem cells have the capability of multipotent differentiation following transfection with a reporter gene, EGFP (enhanced green fluorescent protein) and (iii) to study the characteristics of the stem cells cultured in attached and non-attached plates. NSCs were isolated from embryonic day 98 fetal goat brain, transfected with EGFP gene using lipofection, and subcultured in attached and non-attached plates respectively. The transgenic stem cells were induced to differentiate into osteogenic and endothelial cells in vitro respectively. Markers associated with undifferentiated NSCs and their differentiated cells were tested by RT-PCR (reverse transcription-PCR). The results demonstrated that stem cells could be isolated from embryonic day 98 fetal goat brain, and EGFP gene could be transfected into the cells. The transgenic NSCs were capable of self-renewal, a defining property of stem cells, and were grown as free-floating neurospheres in non-attached plates. When the neurospheres were transferred and cultured in attached plates, cells migrate from the neurospheres and are grown as spindle cells. The stem cells were grown as quasi-circular cells when the single stem cells were cultured in attached plates. Both the NSCs cultured in non-attached and attached plates could express Hes1 (hairy and enhancer of split 1), Oct4 (octamer-binding protein 4), Nanog, Sox2 [SRY (sex-determining region Y)-box 2] and Nestin, while following differentiation cells expressed markers for osteogenic cells (Osteocalcin+ and Osteonectin+) and endothelium (CD34+ and eNOS+). The results demonstrated that the goat EGFP gene transgenic NSCs have the capability of multipotent differentiation, which means that the transgenic NSCs may be useful in cell transplantation studies in future.

Cell differentiation: therapeutical challenges in diabetes.

PubMed

Roche, Enrique; Vicente-Salar, Nestor; Arribas, Maribel; Paredes, Beatriz

2012-01-01

Stem cells, derived from either embryonic or adult tissues, are considered to be potential sources of insulin-secreting cells to be transplanted into type 1 and advanced stages of type 2 diabetic patients. Many laboratories have considered this possibility, resulting in a large amount of published protocols, with a wide degree of complexity among them. Our group was the first to report that it was possible to obtain insulin-secreting cells from mouse embryonic stem cells, proving the feasibility of this new challenge. The same observation was immediately reported using human embryonic stem cells. However, the resulting cell product was not properly characterised, affecting the reproducibility of the protocol by other groups. A more elaborated protocol was developed by Lumelsky and co-workers, demonstrating that neuroectodermal cells could be an alternative source for insulin-producing cells. However, the resulting cells of this protocol produced low amounts of the hormone. This aimed other groups to perform key changes in order to improve the insulin content of the resulting cells. Recently, Baetge's group has published a new protocol based on the knowledge accumulated in pancreatic development. In this protocol, human embryonic stem cells were differentiated into islet-like structures through a five step protocol, emulating the key steps during embryonic development of the endocrine pancreas. The final cell product, however, seemed to be in an immature state, thus further improvement is required. Despite this drawback, the protocol represents the culmination of work performed by different groups and offers new research challenges for the investigators in this exciting field. Concerning adult stem cells, the possibility of identifying pancreatic precursors or of reprogramming extrapancreatic derived cells are key possibilities that may circumvent the problems that appear when using embryonic stem cells, such as immune rejection and tumour formation.

Blastocyst-Derived Stem Cell Populations under Stress: Impact of Nutrition and Metabolism on Stem Cell Potency Loss and Miscarriage.

PubMed

Yang, Yu; Bolnick, Alan; Shamir, Alexandra; Abdulhasan, Mohammed; Li, Quanwen; Parker, G C; Puscheck, Elizabeth E; Rappolee, D A

2017-08-01

Data from in vitro and in vivo models suggest that malnutrition and stress trigger adaptive responses, leading to small for gestational age (SGA) blastocysts with fewer cell numbers. These stress responses are initially adaptive, but become maladaptive with increasing stress exposures. The common stress responses of the blastocyst-derived stem cells, pluripotent embryonic and multipotent placental trophoblast stem cells (ESCs and TSCs), are decreased growth and potency, and increased, imbalanced and irreversible differentiation. SGA embryos may fail to produce sufficient antiluteolytic placental hormone to maintain corpus luteum progesterone secretion that provides nutrition at the implantation site. Myriad stress inputs for the stem cells in the embryo can occur in vitro during in vitro fertilization/assisted reproductive technology (IVF/ART) or in vivo. Paradoxically, stresses that diminish stem cell growth lead to a higher level of differentiation simultaneously which further decreases ESC or TSC numbers in an attempt to functionally compensate for fewer cells. In addition, prolonged or strong stress can cause irreversible differentiation. Resultant stem cell depletion is proposed as a cause of miscarriage via a "quiet" death of an ostensibly adaptive response of stem cells instead of a reactive, violent loss of stem cells or their differentiated progenies.

Stem-cell-activated organ following ultrasound exposure: better transplant option for organ transplantation.

PubMed

Wang, Sen; Li, Yu; Ji, Ying-Chang; Lin, Chang-Min; Man, Cheng; Zheng, Xiao-Xuan

2010-01-01

Although doctors try their best to protect transplants during surgery, there remain great challenges for the higher survival rate and less rejection of transplants after organ transplantation. Growing evidence indicates that the stem cells could function after injury rather than aging, implying that suitable injury may activate the stem cells of damaged organs. Furthermore, it has been revealed that stem cells can be used to induce tolerance in transplantation and the ultrasound has great biological effects on organs. Basing on these facts, we hypothesize that the stem cells within the transplants can be activated by ultrasound with high-frequency and medium-intensity. Therefore, the stem-cell-activated organs (SCAO) can be derived, and the SCAO will be better transplant option for organ transplantation. We postulate the ultrasound can change the molecular activity and/or quantity of the stem cells, the membrane permeability, the cell-cell junctions, and their surrounding microenvironments. As a result, the stem cells are activated, and the SCAO will acquire more regenerative capacity and less rejection. In the paper, we also discuss the process, methods and models for verifying the theory, and the consequences. We believe the theory may provide a practical method for the clinical application of the ultrasound and stem cells in organ transplantation.

Hedgehog signaling regulates the generation of ameloblast progenitors in the continuously growing mouse incisor

PubMed Central

Seidel, Kerstin; Ahn, Christina P.; Lyons, David; Nee, Alexander; Ting, Kevin; Brownell, Isaac; Cao, Tim; Carano, Richard A. D.; Curran, Tom; Schober, Markus; Fuchs, Elaine; Joyner, Alexandra; Martin, Gail R.; de Sauvage, Frederic J.; Klein, Ophir D.

2010-01-01

In many organ systems such as the skin, gastrointestinal tract and hematopoietic system, homeostasis is dependent on the continuous generation of differentiated progeny from stem cells. The rodent incisor, unlike human teeth, grows throughout the life of the animal and provides a prime example of an organ that rapidly deteriorates if newly differentiated cells cease to form from adult stem cells. Hedgehog (Hh) signaling has been proposed to regulate self-renewal, survival, proliferation and/or differentiation of stem cells in several systems, but to date there is little evidence supporting a role for Hh signaling in adult stem cells. We used in vivo genetic lineage tracing to identify Hh-responsive stem cells in the mouse incisor and we show that sonic hedgehog (SHH), which is produced by the differentiating progeny of the stem cells, signals to several regions of the incisor. Using a hedgehog pathway inhibitor (HPI), we demonstrate that Hh signaling is not required for stem cell survival but is essential for the generation of ameloblasts, one of the major differentiated cell types in the tooth, from the stem cells. These results therefore reveal the existence of a positive-feedback loop in which differentiating progeny produce the signal that in turn allows them to be generated from stem cells. PMID:20978073

Advances of Stem Cell Therapeutics in Cutaneous Wound Healing and Regeneration.

PubMed

Kanji, Suman; Das, Hiranmoy

2017-01-01

Cutaneous wound healing is a complex multiple phase process, which overlaps each other, where several growth factors, cytokines, chemokines, and various cells interact in a well-orchestrated manner. However, an imbalance in any of these phases and factors may lead to disruption in harmony of normal wound healing process, resulting in transformation towards chronic nonhealing wounds and abnormal scar formation. Although various therapeutic interventions are available to treat chronic wounds, current wound-care has met with limited success. Progenitor stem cells possess potential therapeutic ability to overcome limitations of the present treatments as it offers accelerated wound repair with tissue regeneration. A substantial number of stem cell therapies for cutaneous wounds are currently under development as a result of encouraging preliminary findings in both preclinical and clinical studies. However, the mechanisms by which these stem cells contribute to the healing process have yet to be elucidated. In this review, we emphasize on the major treatment modalities currently available for the treatment of the wound, role of various interstitial stem cells and exogenous adult stem cells in cutaneous wound healing, and possible mechanisms involved in the healing process.

Brain Cancer Stem Cells Display Preferential Sensitivity to Akt Inhibition

PubMed Central

Eyler, Christine E.; Foo, Wen-Chi; LaFiura, Katherine M.; McLendon, Roger E.; Hjelmeland, Anita B.; Rich, Jeremy N.

2009-01-01

Malignant brain tumors are among the most lethal cancers, and conventional therapies are largely limited to palliation. Novel therapies targeted against specific molecular pathways may offer improved efficacy and reduced toxicity compared to conventional therapies, but initial clinical trials of molecular targeted agents in brain cancer therapy have been frequently disappointing. In brain tumors and other cancers, subpopulations of tumor cells have recently been characterized by their ability to self-renew and initiate tumors. Although these cancer stem cells, or tumor initiating cells, are often only present in small numbers in human tumors, mounting evidence suggests that cancer stem cells contribute to tumor maintenance and therapeutic resistance. Thus, the development of therapies that target cancer stem cell signal transduction and biologies may improve brain tumor patient survival. We now demonstrate that populations enriched for cancer stem cells are preferentially sensitive to an inhibitor of Akt, a prominent cell survival and invasion signaling node. Treatment with an Akt inhibitor more potently reduced the numbers of viable brain cancer stem cells relative to matched non-stem cancer cells associated with a preferential induction of apoptosis and a suppression of neurosphere formation. Akt inhibition also reduced the motility and invasiveness of all tumor cells but had a greater impact on cancer stem cell behaviors. Furthermore, inhibition of Akt activity in cancer stem cells increased survival of immunocompromised mice bearing human glioma xenografts in vivo. Together, these results suggest that Akt inhibitors may function as effective anti-cancer stem cell therapies. PMID:18802038

What do we know about the participation of hematopoietic stem cells in hematopoiesis?

PubMed

Drize, Nina; Petinati, Nataliya

2015-01-01

The demonstrated presence in adult tissues of cells with sustained tissue regenerative potential has given rise to the concept of tissue stem cells. Assays to detect and measure such cells indicate that they have enormous proliferative potential and usually an ability to produce all or many of the mature cell types that define the specialized functionality of the tissue. In the hematopoietic system, one or only a few cells can restore lifelong hematopoiesis of the whole organism. To what extent is the maintenance of hematopoietic stem cells required during normal hematopoiesis? How does the constant maintenance of hematopoiesis occur and what is the behavior of the hematopoietic stem cells in the normal organism? How many of the hematopoietic stem cells are created during the development of the organism? How many hematopoietic stem cells are generating more mature progeny at any given moment? What happens to the population of hematopoietic stem cells in aging? This review will attempt to describe the results of recent research which contradict some of the ideas established over the past 30 years about how hematopoiesis is regulated.

Muscle Stem Cells Undergo Extensive Clonal Drift during Tissue Growth via Meox1-Mediated Induction of G2 Cell-Cycle Arrest.

PubMed

Nguyen, Phong Dang; Gurevich, David Baruch; Sonntag, Carmen; Hersey, Lucy; Alaei, Sara; Nim, Hieu Tri; Siegel, Ashley; Hall, Thomas Edward; Rossello, Fernando Jaime; Boyd, Sarah Elizabeth; Polo, Jose Maria; Currie, Peter David

2017-07-06

Organ growth requires a careful balance between stem cell self-renewal and lineage commitment to ensure proper tissue expansion. The cellular and molecular mechanisms that mediate this balance are unresolved in most organs, including skeletal muscle. Here we identify a long-lived stem cell pool that mediates growth of the zebrafish myotome. This population exhibits extensive clonal drift, shifting from random deployment of stem cells during development to reliance on a small number of dominant clones to fuel the vast majority of muscle growth. This clonal drift requires Meox1, a homeobox protein that directly inhibits the cell-cycle checkpoint gene ccnb1. Meox1 initiates G 2 cell-cycle arrest within muscle stem cells, and disrupting this G 2 arrest causes premature lineage commitment and the resulting defects in muscle growth. These findings reveal that distinct regulatory mechanisms orchestrate stem cell dynamics during organ growth, beyond the G 0 /G 1 cell-cycle inhibition traditionally associated with maintaining tissue-resident stem cells. Copyright © 2017. Published by Elsevier Inc.

Induced Pluripotent Stem Cells: A novel frontier in the study of human primary immunodeficiencies

PubMed Central

Pessach, Itai M.; Ordovas-Montanes, Jose; Zhang, Shen-Ying; Casanova, Jean-Laurent; Giliani, Silvia; Gennery, Andrew R.; Al-Herz, Waleed; Manos, Philip D.; Schlaeger, Thorsten M.; Park, In-Hyun; Rucci, Francesca; Agarwal, Suneet; Mostoslavsky, Gustavo; Daley, George Q.; Notarangelo, Luigi D.

2010-01-01

Background The novel ability to epigenetically reprogram somatic cells into induced pluripotent stem cells through the exogenous expression of transcription promises to revolutionize the study of human diseases. Objective Here we report on the generation of 25 induced pluripotent stem cell lines from 6 patients with various forms of Primary Immunodeficiencies, affecting adaptive and/or innate immunity. Methods Patients’ dermal fibroblasts were reprogrammed by expression of four transcription factors, OCT4, SOX2, KLF4, and c-MYC using a single excisable polycistronic lentiviral vector. Results Induced pluripotent stem cells derived from patients with primary immunodeficiencies show a stemness profile that is comparable to that observed in human embryonic stem cells. Following in vitro differentiation into embryoid bodies, pluripotency of the patient-derived indiced pluripotent stem cells lines was demonstrated by expression of genes characteristic of each of the three embryonic layers. We have confirmed the patient-specific origin of the induced pluripotent stem cell lines, and ascertained maintenance of karyotypic integrity. Conclusion By providing a limitless source of diseased stem cells that can be differentiated into various cell types in vitro, the repository of induced pluripotent stem cell lines from patients with primary immunodeficiencies represents a unique resource to investigate the pathophysiology of hematopoietic and extra-hematopoietic manifestations of these diseases, and may assist in the development of novel therapeutic approaches based on gene correction. PMID:21185069

The effect of diabetes on the wound healing potential of adipose-tissue derived stem cells.

PubMed

Kim, Sue Min; Kim, Yun Ho; Jun, Young Joon; Yoo, Gyeol; Rhie, Jong Won

2016-03-01

To investigate whether diabetes mellitus affects the wound-healing-promoting potential of adipose tissue-derived stem cells, we designed a wound-healing model using diabetic mice. We compared the degree of wound healing between wounds treated with normal adipose tissue-derived stem cells and wounds treated with diabetic adipose tissue-derived stem cells. We evaluated the wound-healing rate, the epithelial tongue distance, the area of granulation tissue, the number of capillary and the number of Ki-67-stained cells. The wound-healing rate was significantly higher in the normal adipose tissue-derived stem cells group than in the diabetic adipose tissue-derived stem cells group; it was also significantly higher in the normal adipose tissue-derived stem cells group than in the control group. Although the diabetic adipose tissue-derived stem cells group showed a better wound-healing rate than the control group, the difference was not statistically significant. Similar trends were observed for the other parameters examined: re-epithelisation and keratinocyte proliferation; granulation tissue formation; and dermal regeneration. However, with regard to the number of capillary, diabetic adipose tissue-derived stem cells retained their ability to promote neovasculisation and angiogenesis. These results reflect the general impairment of the therapeutic potential of diabetic adipose tissue-derived stem cells in vivo. © 2016 Medicalhelplines.com Inc and John Wiley & Sons Ltd.

Isolation and purification of rabbit mesenchymal stem cells using an optimized protocol.

PubMed

Lin, Chunbo; Shen, Maorong; Chen, Weiping; Li, Xiaofeng; Luo, Daoming; Cai, Jinhong; Yang, Yuan

2015-11-01

Mesenchymal stem cells were first isolated and grown in vitro by Friedenstein over 40 yr ago; however, their isolation remains challenging as they lack unique markers for identification and are present in very small quantities in mesenchymal tissues and bone marrow. Using whole marrow samples, common methods for mesenchymal stem cell isolation are the adhesion method and density gradient fractionation. The whole marrow sample adhesion method still results in the nonspecific isolation of mononuclear cells, and activation and/or potential loss of target cells. Density gradient fractionation methods are complicated, and may result in contamination with toxic substances that affect cell viability. In the present study, we developed an optimized protocol for the isolation and purification of mesenchymal stem cells based on the principles of hypotonic lysis and natural sedimentation.

Label-Free, High Resolution, Multi-Modal Light Microscopy for Discrimination of Live Stem Cell Differentiation Status.

PubMed

Zhang, Jing; Moradi, Emilia; Somekh, Michael G; Mather, Melissa L

2018-01-15

A label-free microscopy method for assessing the differentiation status of stem cells is presented with potential application for characterization of therapeutic stem cell populations. The microscopy system is capable of characterizing live cells based on the use of evanescent wave microscopy and quantitative phase contrast (QPC) microscopy. The capability of the microscopy system is demonstrated by studying the differentiation of live immortalised neonatal mouse neural stem cells over a 15 day time course. Metrics extracted from microscope images are assessed and images compared with results from endpoint immuno-staining studies to illustrate the system's performance. Results demonstrate the potential of the microscopy system as a valuable tool for cell biologists to readily identify the differentiation status of unlabelled live cells.

Pituitary stem cells drop their mask.

PubMed

Vankelecom, Hugo

2012-01-01

The pituitary gland represents the organism's endocrine hub, integrating central and peripheral inputs to generate the appropriate hormonal signals that govern key physiological processes. To meet the changing endocrine demands, the gland has to flexibly remodel its hormone-producing cell compartment. Mechanisms underlying pituitary cellular plasticity, as well as homeostatic turnover, are poorly understood. Similar to other tissues, resident stem cells may participate in the generation of newborn cells. Although in the past recurrently postulated to exist, pituitary stem cells remained obscure until the quest recently regained momentum, resulting in a surge of studies that designated very strong candidates for the stem/progenitor cell position. The cells identified express stem cell-associated markers and signaling factors, as well as transcriptional regulators that play essential roles during pituitary embryogenesis. They exhibit the stem cell properties of multilineage differentiation and prominent efflux capacity ("side population" phenotype), and display a topographical pattern reminiscent of niche-like configurations. Yet, the stem cell tenet of long-term self-renewal remains to be unequivocally demonstrated. Taken together, pituitary stem cells commence to drop their mask. While their "face gradually becomes visible, the "character" they play in the pituitary awaits further disclosure. The aim of this review is to highlight the recent progress in pituitary stem/progenitor cell identification by sketching the historical context, describing the new findings with inclusion of critical and cautionary reflections, proposing a tentative stem/progenitor cell model, and pointing out remaining gaps and challenges. The recent acceleration in pituitary stem cell research may announce an exciting era in this endocrine field.

Sodium Caseinate (CasNa) Induces Mobilization of Hematopoietic Stem Cells in a BALB/c Mouse Model

PubMed Central

Santiago-Osorio, Edelmiro; Ledesma-Martínez, Edgar; Aguiñiga-Sánchez, Itzen; Poblano-Pérez, Ignacio; Weiss-Steider, Benny; Montesinos-Montesinos, Juan José; de Lourdes Mora-García, María

2015-01-01

Background Hematopoietic stem cells transplantation has high clinical potential against a wide variety of hematologic, metabolic, and autoimmune diseases and solid tumors. Clinically, hematopoietic stem cells derived from peripheral blood are currently used more than those obtained from sources such as bone marrow. However, mobilizing agents used in the clinic tend to fail in high rates, making the number of mobilized cells insufficient for transplantation. We investigated whether sodium caseinate induces functional mobilization of hematopoietic stem cells into peripheral blood of Balb/c mice. Material/Methods Using a mouse model, we administrated sodium caseinate or Plerixafor, a commercial mobilizing agent, and analyzed counts of hematopoietic stem cells in peripheral blood, and then cells were transplanted into lethally irradiated mice to restore hematopoiesis. All assays were performed at least twice. Results We found that sodium caseinate increases the number of mononuclear cells in peripheral blood with the immunophenotype of hematopoietic stem cells (0.2 to 0.5% LSK cells), allowing them to form colonies of various cell lineages in semisolid medium (p<0.05). This effect is similar to that of Plerixafor, and cells transplanted into lethally irradiated mice can restore hematopoiesis at higher percentages than mononuclear cells mobilized by Plerixafor (40% vs. 20%, respectively). Further, a secondary transplant rescued a separate group of irradiated mice from death, proving definitive evidence of hematopoietic reconstitution after hematopoietic stem cells transplantation. Data are presented as mean ± standard deviation. To determine significant differences between the data, one-way ANOVA and the Tukey test were used. Conclusions Collectively these results show the utility of sodium caseinate as a mobilizer of hematopoietic stem cells and its potential clinical application in transplantation settings. PMID:26409928

Glycyrrhizic acid attenuates stem cell-like phenotypes of human dermal papilla cells.

PubMed

Kiratipaiboon, Chayanin; Tengamnuay, Parkpoom; Chanvorachote, Pithi

2015-12-15

Although the growth of unwanted hair or hirsutism is a harmless condition, many people find it bothersome and embarrassing. Maintaining stem cell features of dermal papilla cells is a critical biological process that keeps the high rate of hair growth. Glycyrrhizic acid has been reported to impair hair growth in some studies; however, its underlying mechanism has not yet been investigated. This study aimed to explore the effect and underlying mechanism of glycyrrhizic acid on stemness of human dermal papilla cells. The stem cell molecular markers, epithelial to mesenchymal markers and Wnt/β-catenin-associated proteins of human dermal papilla cell line and primary human dermal papilla cells were analysed by western blot analysis and immunocytochemistry. The present study demonstrated that glycyrrhizic acid significantly depressed the stemness of dermal papilla cells in dose- and time-dependent manners. Clonogenicity and stem cell markers in the glycyrrhizic acid-treated cells were found to gradually decrease in the culture in a time-dependent manner. Our results demonstrated that glycyrrhizic acid exerted the stem cell suppressing effects through the interruption of ATP-dependent tyrosine kinase/glycogen synthase kinase3β-dependent mechanism which in turn down-regulated the β-catenin signalling pathway, coupled with decreased its down-stream epithelial-mesenchymal transition and self-renewal transcription factors, namely, Oct-4, Nanog, Sox2, ZEB1 and Snail. The effect of glycyrrhizic acid on the reduction of stem cell features was also observed in the primary dermal papilla cells directly obtained from human hair follicles. These results revealed a novel molecular mechanism of glycyrrhizic acid in regulation of dermal papilla cells and provided the evidence supporting the use of this compound in suppressing the growth of unwanted hair. Copyright © 2015 Elsevier GmbH. All rights reserved.

Sodium Caseinate (CasNa) Induces Mobilization of Hematopoietic Stem Cells in a BALB/c Mouse Model.

PubMed

Santiago-Osorio, Edelmiro; Ledesma-Martínez, Edgar; Aguiñiga-Sánchez, Itzen; Poblano-Pérez, Ignacio; Weiss-Steider, Benny; Montesinos-Montesinos, Juan José; Mora-García, María de Lourdes

2015-09-25

BACKGROUND Hematopoietic stem cells transplantation has high clinical potential against a wide variety of hematologic, metabolic, and autoimmune diseases and solid tumors. Clinically, hematopoietic stem cells derived from peripheral blood are currently used more than those obtained from sources such as bone marrow. However, mobilizing agents used in the clinic tend to fail in high rates, making the number of mobilized cells insufficient for transplantation. We investigated whether sodium caseinate induces functional mobilization of hematopoietic stem cells into peripheral blood of Balb/c mice. MATERIAL AND METHODS Using a mouse model, we administrated sodium caseinate or Plerixafor, a commercial mobilizing agent, and analyzed counts of hematopoietic stem cells in peripheral blood, and then cells were transplanted into lethally irradiated mice to restore hematopoiesis. All assays were performed at least twice. RESULTS We found that sodium caseinate increases the number of mononuclear cells in peripheral blood with the immunophenotype of hematopoietic stem cells (0.2 to 0.5% LSK cells), allowing them to form colonies of various cell lineages in semisolid medium (p<0.05). This effect is similar to that of Plerixafor, and cells transplanted into lethally irradiated mice can restore hematopoiesis at higher percentages than mononuclear cells mobilized by Plerixafor (40% vs. 20%, respectively). Further, a secondary transplant rescued a separate group of irradiated mice from death, proving definitive evidence of hematopoietic reconstitution after hematopoietic stem cells transplantation. Data are presented as mean ± standard deviation. To determine significant differences between the data, one-way ANOVA and the Tukey test were used. CONCLUSIONS Collectively these results show the utility of sodium caseinate as a mobilizer of hematopoietic stem cells and its potential clinical application in transplantation settings.

Mesenchymal Stem Cells From Bone Marrow, Adipose Tissue, and Lung Tissue Differentially Mitigate Lung and Distal Organ Damage in Experimental Acute Respiratory Distress Syndrome.

PubMed

Silva, Johnatas D; Lopes-Pacheco, Miquéias; Paz, Ana H R; Cruz, Fernanda F; Melo, Elga B; de Oliveira, Milena V; Xisto, Débora G; Capelozzi, Vera L; Morales, Marcelo M; Pelosi, Paolo; Cirne-Lima, Elizabeth; Rocco, Patricia R M

2018-02-01

Mesenchymal stem cells-based therapies have shown promising effects in experimental acute respiratory distress syndrome. Different mesenchymal stem cells sources may result in diverse effects in respiratory diseases; however, there is no information regarding the best source of mesenchymal stem cells to treat pulmonary acute respiratory distress syndrome. We tested the hypothesis that mesenchymal stem cells derived from bone marrow, adipose tissue, and lung tissue would lead to different beneficial effects on lung and distal organ damage in experimental pulmonary acute respiratory distress syndrome. Animal study and primary cell culture. Laboratory investigation. Seventy-five Wistar rats. Wistar rats received saline (control) or Escherichia coli lipopolysaccharide (acute respiratory distress syndrome) intratracheally. On day 2, acute respiratory distress syndrome animals were further randomized to receive saline or bone marrow, adipose tissue, or lung tissue mesenchymal stem cells (1 × 10 cells) IV. Lung mechanics, histology, and protein levels of inflammatory mediators and growth factors were analyzed 5 days after mesenchymal stem cells administration. RAW 264.7 cells (a macrophage cell line) were incubated with lipopolysaccharide followed by coculture or not with bone marrow, adipose tissue, and lung tissue mesenchymal stem cells (10 cells/mL medium). Regardless of mesenchymal stem cells source, cells administration improved lung function and reduced alveolar collapse, tissue cellularity, collagen, and elastic fiber content in lung tissue, as well as decreased apoptotic cell counts in liver. Bone marrow and adipose tissue mesenchymal stem cells administration also reduced levels of tumor necrosis factor-α, interleukin-1β, keratinocyte-derived chemokine, transforming growth factor-β, and vascular endothelial growth factor, as well as apoptotic cell counts in lung and kidney, while increasing expression of keratinocyte growth factor in lung tissue. Additionally, mesenchymal stem cells differently modulated the secretion of biomarkers by macrophages depending on their source. Mesenchymal stem cells from different sources led to variable responses in lungs and distal organs. Bone marrow and adipose tissue mesenchymal stem cells yielded greater beneficial effects than lung tissue mesenchymal stem cells. These findings may be regarded as promising in clinical trials.

Bone Marrow Stem Cells in Clinical Application: Harnessing Paracrine Roles and Niche Mechanisms

NASA Astrophysics Data System (ADS)

Backly, Rania M. El; Cancedda, Ranieri

The being of any individual throughout life is a dynamic process relying on the capacity to retain processes of self-renewal and differentiation, both of which are hallmarks of stem cells. Although limited in the adult human organism, regeneration and repair do take place in virtue of the presence of adult stem cells. In the bone marrow, two major populations of stem cells govern the dynamic equilibrium of both hemopoiesis and skeletal homeostasis; the hematopoietic and the mesenchymal stem cells. Recent cell based clinical trials utilizing bone marrow-derived stem cells as therapeutic agents have revealed promising results, while others have failed to display as such. It is therefore imperative to strive to understand the mechanisms by which these cells function in vivo, how their properties can be maintained ex-vivo, and to explore further their recently highlighted immunomodulatory and trophic effects.

Transcriptomic profiling of curcumin treated human breast stem cells identifies a role for stearoyl coa-desaturase in breast cancer prevention

PubMed Central

Colacino, Justin A.; McDermott, Sean P.; Sartor, Maureen A.; Wicha, Max S.; Rozek, Laura S.

2017-01-01

Curcumin is a potential agent for both the prevention and treatment of cancers. Curcumin treatment alone, or in combination with piperine, limits breast stem cell self-renewal while remaining non-toxic to normal differentiated cells. We paired fluorescence activated cell sorting with RNA sequencing to characterize the genome-wide changes induced specifically in normal breast stem cells following treatment with these compounds. We generated genome-wide maps of the transcriptional changes that occur in epithelial-like (ALDH+) and mesenchymal-like (ALDH−/CD44+/CD24−) normal breast stem/progenitor cells following treatment with curcumin and piperine. We show that curcumin targets both stem cell populations by down-regulating expression of breast stem cell genes including ALDH1A3, CD49f, PROM1, and TP63. We also identified novel genes and pathways targeted by curcumin, including downregulation of SCD. Transient siRNA knockdown of SCD in MCF10A cells significantly inhibited mammosphere formation and the mean proportion of CD44+/CD24− cells, suggesting that SCD is a regulator of breast stemness and a target of curcumin in breast stem cells. These findings extend previous reports of curcumin targeting stem cells, here in two phenotypically distinct stem/progenitor populations isolated from normal human breast tissue. We identified novel mechanisms by which curcumin and piperine target breast stem cell self-renewal, such as by targeting lipid metabolism, providing a mechanistic link between curcumin treatment and stem cell self renewal. These results elucidate the mechanisms by which curcumin may act as a cancer preventive compound and provide novel targets for cancer prevention and treatment. PMID:27306423

Transcriptomic profiling of curcumin-treated human breast stem cells identifies a role for stearoyl-coa desaturase in breast cancer prevention.

PubMed

Colacino, Justin A; McDermott, Sean P; Sartor, Maureen A; Wicha, Max S; Rozek, Laura S

2016-07-01

Curcumin is a potential agent for both the prevention and treatment of cancers. Curcumin treatment alone, or in combination with piperine, limits breast stem cell self-renewal, while remaining non-toxic to normal differentiated cells. We paired fluorescence-activated cell sorting with RNA sequencing to characterize the genome-wide changes induced specifically in normal breast stem cells following treatment with these compounds. We generated genome-wide maps of the transcriptional changes that occur in epithelial-like (ALDH+) and mesenchymal-like (ALDH-/CD44+/CD24-) normal breast stem/progenitor cells following treatment with curcumin and piperine. We show that curcumin targets both stem cell populations by down-regulating expression of breast stem cell genes including ALDH1A3, CD49f, PROM1, and TP63. We also identified novel genes and pathways targeted by curcumin, including downregulation of SCD. Transient siRNA knockdown of SCD in MCF10A cells significantly inhibited mammosphere formation and the mean proportion of CD44+/CD24- cells, suggesting that SCD is a regulator of breast stemness and a target of curcumin in breast stem cells. These findings extend previous reports of curcumin targeting stem cells, here in two phenotypically distinct stem/progenitor populations isolated from normal human breast tissue. We identified novel mechanisms by which curcumin and piperine target breast stem cell self-renewal, such as by targeting lipid metabolism, providing a mechanistic link between curcumin treatment and stem cell self-renewal. These results elucidate the mechanisms by which curcumin may act as a cancer-preventive compound and provide novel targets for cancer prevention and treatment.

Pink1 and Parkin regulate Drosophila intestinal stem cell proliferation during stress and aging.

PubMed

Koehler, Christopher L; Perkins, Guy A; Ellisman, Mark H; Jones, D Leanne

2017-08-07

Intestinal stem cells (ISCs) maintain the midgut epithelium in Drosophila melanogaster Proper cellular turnover and tissue function rely on tightly regulated rates of ISC division and appropriate differentiation of daughter cells. However, aging and epithelial injury cause elevated ISC proliferation and decreased capacity for terminal differentiation of daughter enteroblasts (EBs). The mechanisms causing functional decline of stem cells with age remain elusive; however, recent findings suggest that stem cell metabolism plays an important role in the regulation of stem cell activity. Here, we investigate how alterations in mitochondrial homeostasis modulate stem cell behavior in vivo via RNA interference-mediated knockdown of factors involved in mitochondrial dynamics. ISC/EB-specific knockdown of the mitophagy-related genes Pink1 or Parkin suppresses the age-related loss of tissue homeostasis, despite dramatic changes in mitochondrial ultrastructure and mitochondrial damage in ISCs/EBs. Maintenance of tissue homeostasis upon reduction of Pink1 or Parkin appears to result from reduction of age- and stress-induced ISC proliferation, in part, through induction of ISC senescence. Our results indicate an uncoupling of cellular, tissue, and organismal aging through inhibition of ISC proliferation and provide insight into strategies used by stem cells to maintain tissue homeostasis despite severe damage to organelles. © 2017 Koehler et al.

TOO MANY MOUTHS promotes cell fate progression in stomatal development of Arabidopsis stems.

PubMed

Bhave, Neela S; Veley, Kira M; Nadeau, Jeanette A; Lucas, Jessica R; Bhave, Sanjay L; Sack, Fred D

2009-01-01

Mutations in TOO MANY MOUTHS (TMM), which encodes a receptor-like protein, cause stomatal patterning defects in Arabidopsis leaves but eliminate stomatal formation in stems. Stomatal development in wild-type and tmm stems was analyzed to define TMM function. Epidermal cells in young tmm stems underwent many asymmetric divisions characteristic of entry into the stomatal pathway. The resulting precursor cells, meristemoids, appropriately expressed cell fate markers such as pTMM:GFP. However, instead of progressing developmentally by forming a guard mother cell, the meristemoids arrested, dedifferentiated, and enlarged. Thus asymmetric divisions are necessary but not sufficient for stomatal formation in stems, and TMM promotes the fate and developmental progression of early precursor cells. Comparable developmental and mature stomatal phenotypes were also found in tmm hypocotyls and in the proximal flower stalk. TMM is also a positive regulator of meristemoid division in leaves suggesting that TMM generally promotes meristemoid activity. Our results are consistent with a model in which TMM interacts with other proteins to modulate precursor cell fate and progression in an organ and domain-specific manner. Finally, the consistent presence of a small number of dedifferentiated meristemoids in mature wild-type stems suggests that precursor cell arrest is a normal feature of Arabidopsis stem development.

A Systematic Review of Mesenchymal Stem Cells in Spinal Cord Injury, Intervertebral Disc Repair and Spinal Fusion.

PubMed

Khan, Shujhat; Mafi, Pouya; Mafi, Reza; Khan, Wasim

2018-01-01

Spinal surgery presents a challenge for both neurosurgery and orthopaedic surgery. Due to the heterogeneous differentiation potential of mesenchymal stem cells, there is much interest in the treatment of spine surgery. Animal and human trials focussing on the efficacy of mesenchymal stem cells in spinal cord injury, spine fusion and disc degeneration were included in this systematic review. Published articles up to January 2016 from MEDLINE, PubMed and Ovid were used by searching for specific terms. Of the 2595 articles found, 53 met the selection criteria and were included for analysis (16 on spinal cord injury, 28 on intervertebral disc repair and 9 on spinal fusion). Numerous studies reported better results when the mesenchymal stem cells were used in co-culture with other cells or used in scaffolds. Mesenchymal stem cells were also found to have an immune-modulatory role, which can improve surgical outcome. This systematic review suggests that mesenchymal stem cells can be used safely and effectively for these spinal surgery treatments. Whilst, in certain studies, mesenchymal stem cells did not necessarily show improved results from existing treatments, they provide an alternative option. This can reduce morbidity that arises from current surgical treatment. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Stem cell sources for clinical islet transplantation in type 1 diabetes: embryonic and adult stem cells.

PubMed

Miszta-Lane, Helena; Mirbolooki, Mohammadreza; James Shapiro, A M; Lakey, Jonathan R T

2006-01-01

Lifelong immunosuppressive therapy and inadequate sources of transplantable islets have led the islet transplantation benefits to less than 0.5% of type 1 diabetics. Whereas the potential risk of infection by animal endogenous viruses limits the uses of islet xeno-transplantation, deriving islets from stem cells seems to be able to overcome the current problems of islet shortages and immune compatibility. Both embryonic (derived from the inner cell mass of blastocysts) and adult stem cells (derived from adult tissues) have shown controversial results in secreting insulin in vitro and normalizing hyperglycemia in vivo. ESCs research is thought to have much greater developmental potential than adult stem cells; however it is still in the basic research phase. Existing ESC lines are not believed to be identical or ideal for generating islets or beta-cells and additional ESC lines have to be established. Research with ESCs derived from humans is controversial because it requires the destruction of a human embryo and/or therapeutic cloning, which some believe is a slippery slope to reproductive cloning. On the other hand, adult stem cells are already in some degree specialized, recipients may receive their own stem cells. They are flexible but they have shown mixed degree of availability. Adult stem cells are not pluripotent. They may not exist for all organs. They are difficult to purify and they cannot be maintained well outside the body. In order to draw the future avenues in this field, existent discrepancies between the results need to be clarified. In this study, we will review the different aspects and challenges of using embryonic or adult stem cells in clinical islet transplantation for the treatment of type 1 diabetes.

Stimulatory effect of icariin on the proliferation of neural stem cells from rat hippocampus.

PubMed

Fu, Xiaolong; Li, Shujun; Zhou, Shaoyu; Wu, Qin; Jin, Feng; Shi, Jingshan

2018-01-29

Icariin (ICA), a major ingredient of Epimediumbrevicornum, has various pharmacological activities including central nervous system protective functions such as the improvement of learning and memory function in mice models of Alzheimer's disease. It has been reported that ICA can promote regeneration of peripheral nerve and functional recovery. The purpose of this study was to investigate the potentiating effect of ICA on the proliferation of rat hippocampal neural stem cells, and explore the possible mechanism involved. Primary neural stem cells were prepared from the hippocampus of newly born SD rats, and cells were cultured in special stem cell culture medium. Neural stem cells were confirmed by immunofluorescence detection of nestin, NSE and GFAP expression. The effect of ICA on the growth and proliferation of the neural stem cells was evaluated by 5-ethynyl-2-deoxyuridine (EdU) labeling of proliferating cells, and photomicrographic images of the cultured neural stem cells. Further, the mechanism of ICA-induced cell proliferation of neural stem cells was investigated by analyzing the gene and protein expression of cell cycle related genes cyclin D1 and p21. The present study showed that icariin promotes the growth and proliferation of neural stem cells from rat hippocampus in a dose-dependent manner. Incubation of cells with icariin resulted in significant increase in the number of stem cell spheres as well as the increased incorporation of EdU when compared with cells exposed to control vehicle. In addition, it was found that icariin-induced effect on neural stem cells is associated with increased mRNA and protein expression of cell cycle genes cyclin D1 and p21. This study evidently demonstrates the potentiating effect of ICA on neural stem cell growth and proliferation, which might be mediated through regulation of cell cycle gene and protein expression promoting cell cycle progression.

Effects of different feeder layers on culture of bovine embryonic stem cell-like cells in vitro.

PubMed

Cong, Shan; Cao, Guifang; Liu, Dongjun

2014-12-01

To find a suitable feeder layer is important for successful culture conditions of bovine embryonic stem cell-like cells. In this study, expression of pluripotency-related genes OCT4, SOX2 and NANOG in bovine embryonic stem cell-like cells on mouse embryonic fibroblast feeder layers at 1-5 passages were monitored in order to identify the possible reason that bovine embryonic stem cell-like cells could not continue growth and passage. Here, we developed two novel feeder layers, mixed embryonic fibroblast feeder layers of mouse and bovine embryonic fibroblast at different ratios and sources including mouse fibroblast cell lines. The bovine embryonic stem cell-like cells generated in our study displayed typical stem cell morphology and expressed specific markers such as OCT4, stage-specific embryonic antigen 1 and 4, alkaline phosphatase, SOX2, and NANOG mRNA levels. When feeder layers and cell growth factors were removed, the bovine embryonic stem cell-like cells formed embryoid bodies in a suspension culture. Furthermore, we compared the expression of the pluripotent markers during bovine embryonic stem cell-like cell in culture on mixed embryonic fibroblast feeder layers, including mouse fibroblast cell lines feeder layers and mouse embryonic fibroblast feeder layers by real-time quantitative polymerase chain reaction. Results suggested that mixed embryonic fibroblast and sources including mouse fibroblast cell lines feeder layers were more suitable for long-term culture and growth of bovine embryonic stem cell-like cells than mouse embryonic fibroblast feeder layers. The findings may provide useful experimental data for the establishment of an appropriate culture system for bovine embryonic stem cell lines.

Characterization of TLX expression in neural stem cells and progenitor cells in adult brains.

PubMed

Li, Shengxiu; Sun, Guoqiang; Murai, Kiyohito; Ye, Peng; Shi, Yanhong

2012-01-01

TLX has been shown to play an important role in regulating the self-renewal and proliferation of neural stem cells in adult brains. However, the cellular distribution of endogenous TLX protein in adult brains remains to be elucidated. In this study, we used immunostaining with a TLX-specific antibody to show that TLX is expressed in both neural stem cells and transit-amplifying neural progenitor cells in the subventricular zone (SVZ) of adult mouse brains. Then, using a double thymidine analog labeling approach, we showed that almost all of the self-renewing neural stem cells expressed TLX. Interestingly, most of the TLX-positive cells in the SVZ represented the thymidine analog-negative, relatively quiescent neural stem cell population. Using cell type markers and short-term BrdU labeling, we demonstrated that TLX was also expressed in the Mash1+ rapidly dividing type C cells. Furthermore, loss of TLX expression dramatically reduced BrdU label-retaining neural stem cells and the actively dividing neural progenitor cells in the SVZ, but substantially increased GFAP staining and extended GFAP processes. These results suggest that TLX is essential to maintain the self-renewing neural stem cells in the SVZ and that the GFAP+ cells in the SVZ lose neural stem cell property upon loss of TLX expression. Understanding the cellular distribution of TLX and its function in specific cell types may provide insights into the development of therapeutic tools for neurodegenerative diseases by targeting TLX in neural stem/progenitors cells.

Characterization of TLX Expression in Neural Stem Cells and Progenitor Cells in Adult Brains

PubMed Central

Li, Shengxiu; Sun, Guoqiang; Murai, Kiyohito; Ye, Peng; Shi, Yanhong

2012-01-01

TLX has been shown to play an important role in regulating the self-renewal and proliferation of neural stem cells in adult brains. However, the cellular distribution of endogenous TLX protein in adult brains remains to be elucidated. In this study, we used immunostaining with a TLX-specific antibody to show that TLX is expressed in both neural stem cells and transit-amplifying neural progenitor cells in the subventricular zone (SVZ) of adult mouse brains. Then, using a double thymidine analog labeling approach, we showed that almost all of the self-renewing neural stem cells expressed TLX. Interestingly, most of the TLX-positive cells in the SVZ represented the thymidine analog-negative, relatively quiescent neural stem cell population. Using cell type markers and short-term BrdU labeling, we demonstrated that TLX was also expressed in the Mash1+ rapidly dividing type C cells. Furthermore, loss of TLX expression dramatically reduced BrdU label-retaining neural stem cells and the actively dividing neural progenitor cells in the SVZ, but substantially increased GFAP staining and extended GFAP processes. These results suggest that TLX is essential to maintain the self-renewing neural stem cells in the SVZ and that the GFAP+ cells in the SVZ lose neural stem cell property upon loss of TLX expression.Understanding the cellular distribution of TLX and its function in specific cell types may provide insights into the development of therapeutic tools for neurodegenerative diseases by targeting TLX in neural stem/progenitors cells. PMID:22952666

Fanconi anemia genes are highly expressed in primitive CD34+ hematopoietic cells

PubMed Central

Aubé, Michel; Lafrance, Matthieu; Brodeur, Isabelle; Delisle, Marie-Chantal; Carreau, Madeleine

2003-01-01

Background Fanconi anemia (FA) is a complex recessive genetic disease characterized by progressive bone marrow failure (BM) and a predisposition to cancer. We have previously shown using the Fancc mouse model that the progressive BM failure results from a hematopoietic stem cell defect suggesting that function of the FA genes may reside in primitive hematopoietic stem cells. Methods Since genes involved in stem cell differentiation and/or maintenance are usually regulated at the transcription level, we used a semiquantitative RT-PCR method to evaluate FA gene transcript levels in purified hematopoietic stem cells. Results We show that most FA genes are highly expressed in primitive CD34-positive and negative cells compared to lower levels in more differentiated cells. However, in CD34- stem cells the Fancc gene was found to be expressed at low levels while Fancg was undetectable in this population. Furthermore, Fancg expression is significantly decreased in Fancc -/- stem cells as compared to wild-type cells while the cancer susceptibility genes Brca1 and Fancd1/Brac2 are upregulated in Fancc-/- hematopoietic cells. Conclusions These results suggest that FA genes are regulated at the mRNA level, that increased Fancc expression in LTS-CD34+ cells correlates with a role at the CD34+ differentiation stage and that lack of Fancc affects the expression of other FA gene, more specifically Fancg and Fancd1/Brca2, through an unknown mechanism. PMID:12809565

[Stem cells therapy in amyotrophic lateral sclerosis treatment. A critical view].

PubMed

Soler, Bernardita; Fadic, Ricardo; von Bernhardi, Rommy

2011-04-01

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease. At present, there are not curative therapies for ALS. Pathogenic and progression mechanisms suggest the existence of oxidative stress, abnormal intracellular protein aggregation, mitochondrial dysfunction, axonal transport impairment, impairment of trophic support, altered glial cell function, and glutamate excitoxicity. To evaluate therapeutic results with adult stem cell for ALS treatment. Stem cells represent a potential therapeutic strategy, because their biological mechanisms could act on several of the pathogenic mechanisms proposed for ALS. Bone marrow mesenchymal stem cells are especially interesting among adult stem cells. Mesenchymal stem cells can differentiate in all central nervous system cells and potentially replace them. Furthermore, they have immunomodulatory effects, secreting, especially in neuroinflammatory environments, neurotrophic and antiinflammatory factors. Studies in murine models of ALS show decrease of inflammation and disease progression, and increase on animal highly heterogeneous, suggest that mesenchymal stem cells transplant in ALS appears to be safe. However, they fail showing clinical improvement of patients. Additional preclinical studies are necessary to refine this therapeutic approach, to assess long term survival and differentiation of mesenchymal stem cells, dosing, biological activity and safety should be conducted before any planning further human testing occurs.

Tuning of major signaling networks (TGF-β, Wnt, Notch and Hedgehog) by miRNAs in human stem cells commitment to different lineages: Possible clinical application.

PubMed

Aval, Sedigheh Fekri; Lotfi, Hajie; Sheervalilou, Roghayeh; Zarghami, Nosratollah

2017-07-01

Two distinguishing characteristics of stem cells, their continuous division in the undifferentiated state and growth into any cell types, are orchestrated by a number of cell signaling pathways. These pathways act as a niche factor in controlling variety of stem cells. The core stem cell signaling pathways include Wingless-type (Wnt), Hedgehog (HH), and Notch. Additionally, they critically regulate the self-renewal and survival of cancer stem cells. Conversely, stem cells' main properties, lineage commitment and stemness, are tightly controlled by epigenetic mechanisms such as DNA methylation, histone modifications and non-coding RNA-mediated regulatory events. MicroRNAs (miRNAs) are cellular switches that modulate stem cells outcomes in response to diverse extracellular signals. Numerous scientific evidences implicating miRNAs in major signal transduction pathways highlight new crosstalks of cellular processes. Aberrant signaling pathways and miRNAs levels result in developmental defects and diverse human pathologies. This review discusses the crosstalk between the components of main signaling networks and the miRNA machinery, which plays a role in the context of stem cells development and provides a set of examples to illustrate the extensive relevance of potential novel therapeutic targets. Copyright © 2017. Published by Elsevier Masson SAS.

BDNF improves the efficacy ERG amplitude maintenance by transplantation of retinal stem cells in RCS rats.

PubMed

Tian, Chunyu; Weng, Chuan Chuang; Yin, Zheng Qin

2010-01-01

The aim of this study was to evaluate the efficacy of subretinal transplantation of rat retinal stem cell when combined with Brain-derived neurotrophic factor (BDNF) in a rat model of retinal degeneration - Royal College of Surgeons (RCS) rats. Retinal stem cells were derived from embryonic day 17 Long-Evans rats and pre-labeled with fluorescence pigment-DiI prior to transplant procedures. RCS rats received injections of retinal stem cells, stem cells+BDNF, phosphate buffered saline or BNDF alone (n = 3 eyes for each procedure). At 1, 2 and 3 months after transplantation, the electroretinogram (ERG) was assessed and the outer nuclear layer thickness measured. The eyes receiving retinal stem cell and stem cell+BDNF transplants showed better photoreceptor maintenance than the other groups (P < 0.01) at all time points. One month after retina transplantation, the amplitudes of rod-ERG and Max-ERG b waves were significantly higher the eyes with stem cells+BDNF (P < 0.01), however, this difference was not seen at two and three months post transplantation. BDNF treatment alone group (without transplanted cells) had no effect when compared to buffer injections. The present results indicate that BDNF can enhance the short-term efficacy of the retinal stem cell transplantation in treating retinal degenerative disease.

[Characterization of stem cells derived from the neonatal auditory sensory epithelium].

PubMed

Diensthuber, M; Heller, S

2010-11-01

In contrast to regenerating hair cell-bearing organs of nonmammalian vertebrates the adult mammalian organ of Corti appears to have lost its ability to maintain stem cells. The result is a lack of regenerative ability and irreversible hearing loss following auditory hair cell death. Unexpectedly, the neonatal auditory sensory epithelium has recently been shown to harbor cells with stem cell features. The origin of these cells within the cochlea's sensory epithelium is unknown. We applied a modified neurosphere assay to identify stem cells within distinct subregions of the neonatal mouse auditory sensory epithelium. Sphere cells were characterized by multiple markers and morphologic techniques. Our data reveal that both the greater and the lesser epithelial ridge contribute to the sphere-forming stem cell population derived from the auditory sensory epithelium. These self-renewing sphere cells express a variety of markers for neural and otic progenitor cells and mature inner ear cell types. Stem cells can be isolated from specific regions of the auditory sensory epithelium. The distinct features of these cells imply a potential application in the development of a cell replacement therapy to regenerate the damaged sensory epithelium.

Increased centrosome amplification in aged stem cells of the Drosophila midgut

DOE Office of Scientific and Technical Information (OSTI.GOV)

Park, Joung-Sun; Pyo, Jung-Hoon; Na, Hyun-Jin

Highlights: • Increased centrosome amplification in ISCs of aged Drosophila midguts. • Increased centrosome amplification in ISCs of oxidative stressed Drosophila midguts. • Increased centrosome amplification in ISCs by overexpression of PVR, EGFR, and AKT. • Supernumerary centrosomes can be responsible for abnormal ISC polyploid cells. • Supernumerary centrosomes can be a useful marker for aging stem cells. - Abstract: Age-related changes in long-lived tissue-resident stem cells may be tightly linked to aging and age-related diseases such as cancer. Centrosomes play key roles in cell proliferation, differentiation and migration. Supernumerary centrosomes are known to be an early event in tumorigenesismore » and senescence. However, the age-related changes of centrosome duplication in tissue-resident stem cells in vivo remain unknown. Here, using anti-γ-tubulin and anti-PH3, we analyzed mitotic intestinal stem cells with supernumerary centrosomes in the adult Drosophila midgut, which may be a versatile model system for stem cell biology. The results showed increased centrosome amplification in intestinal stem cells of aged and oxidatively stressed Drosophila midguts. Increased centrosome amplification was detected by overexpression of PVR, EGFR, and AKT in intestinal stem cells/enteroblasts, known to mimic age-related changes including hyperproliferation of intestinal stem cells and hyperplasia in the midgut. Our data show the first direct evidence for the age-related increase of centrosome amplification in intestinal stem cells and suggest that the Drosophila midgut is an excellent model for studying molecular mechanisms underlying centrosome amplification in aging adult stem cells in vivo.« less

Expansion of Multipotent Stem Cells from the Adult Human Brain

PubMed Central

Murrell, Wayne; Palmero, Emily; Bianco, John; Stangeland, Biljana; Joel, Mrinal; Paulson, Linda; Thiede, Bernd; Grieg, Zanina; Ramsnes, Ingunn; Skjellegrind, Håvard K.; Nygård, Ståle; Brandal, Petter; Sandberg, Cecilie; Vik-Mo, Einar; Palmero, Sheryl; Langmoen, Iver A.

2013-01-01

The discovery of stem cells in the adult human brain has revealed new possible scenarios for treatment of the sick or injured brain. Both clinical use of and preclinical research on human adult neural stem cells have, however, been seriously hampered by the fact that it has been impossible to passage these cells more than a very few times and with little expansion of cell numbers. Having explored a number of alternative culturing conditions we here present an efficient method for the establishment and propagation of human brain stem cells from whatever brain tissue samples we have tried. We describe virtually unlimited expansion of an authentic stem cell phenotype. Pluripotency proteins Sox2 and Oct4 are expressed without artificial induction. For the first time multipotency of adult human brain-derived stem cells is demonstrated beyond tissue boundaries. We characterize these cells in detail in vitro including microarray and proteomic approaches. Whilst clarification of these cells’ behavior is ongoing, results so far portend well for the future repair of tissues by transplantation of an adult patient’s own-derived stem cells. PMID:23967194

Stem cell therapy: A novel & futuristic treatment modality for disaster injuries

PubMed Central

Gurudutta, G.U.; Satija, Neeraj Kumar; Singh, Vimal Kishor; Verma, Yogesh Kumar; Gupta, Pallavi; Tripathi, R.P.

2012-01-01

Stem cell therapy hold the potential to meet the demand for transplant cells/tissues needed for treating damages resulting from both natural and man-made disasters. Pluripotency makes embryonic stem cells and induced pluripotent stem cells ideal for use, but their teratogenic character is a major hindrance. Therapeutic benefits of bone marrow transplantation are well known but characterizing the potentialities of haematopoietic and mesenchymal cells is essential. Haematopoietic stem cells (HSCs) have been used for treating both haematopoietic and non-haematopoietic disorders. Ease of isolation, in vitro expansion, and hypoimmunogenecity have brought mesenchymal stem cells (MSCs) into limelight. Though differentiation of MSCs into tissue-specific cells has been reported, differentiation-independent mechanisms seem to play a more significant role in tissue repair which need to be addressed further. The safety and feasibility of MSCs have been demonstrated in clinical trials, and their use in combination with HSC for radiation injury treatment seems to have extended benefit. Therefore, using stem cells for treatment of disaster injuries along with the conventional medical practice would likely accelerate the repair process and improve the quality of life of the victim. PMID:22382178

mtDNA Mutagenesis Disrupts Pluripotent Stem Cell Function by Altering Redox Signaling

PubMed Central

Hämäläinen, Riikka H.; Ahlqvist, Kati J.; Ellonen, Pekka; Lepistö, Maija; Logan, Angela; Otonkoski, Timo; Murphy, Michael P.; Suomalainen, Anu

2015-01-01

Summary mtDNA mutagenesis in somatic stem cells leads to their dysfunction and to progeria in mouse. The mechanism was proposed to involve modification of reactive oxygen species (ROS)/redox signaling. We studied the effect of mtDNA mutagenesis on reprogramming and stemness of pluripotent stem cells (PSCs) and show that PSCs select against specific mtDNA mutations, mimicking germline and promoting mtDNA integrity despite their glycolytic metabolism. Furthermore, mtDNA mutagenesis is associated with an increase in mitochondrial H2O2, reduced PSC reprogramming efficiency, and self-renewal. Mitochondria-targeted ubiquinone, MitoQ, and N-acetyl-L-cysteine efficiently rescued these defects, indicating that both reprogramming efficiency and stemness are modified by mitochondrial ROS. The redox sensitivity, however, rendered PSCs and especially neural stem cells sensitive to MitoQ toxicity. Our results imply that stem cell compartment warrants special attention when the safety of new antioxidants is assessed and point to an essential role for mitochondrial redox signaling in maintaining normal stem cell function. PMID:26027936

Health Span-Extending Activity of Human Amniotic Membrane- and Adipose Tissue-Derived Stem Cells in F344 Rats.

PubMed

Kim, Dajeong; Kyung, Jangbeen; Park, Dongsun; Choi, Ehn-Kyoung; Kim, Kwang Sei; Shin, Kyungha; Lee, Hangyoung; Shin, Il Seob; Kang, Sung Keun; Ra, Jeong Chan; Kim, Yun-Bae

2015-10-01

Aging brings about the progressive decline in cognitive function and physical activity, along with losses of stem cell population and function. Although transplantation of muscle-derived stem/progenitor cells extended the health span and life span of progeria mice, such effects in normal animals were not confirmed. Human amniotic membrane-derived mesenchymal stem cells (AMMSCs) or adipose tissue-derived mesenchymal stem cells (ADMSCs) (1×10(6) cells per rat) were intravenously transplanted to 10-month-old male F344 rats once a month throughout their lives. Transplantation of AMMSCs and ADMSCs improved cognitive and physical functions of naturally aging rats, extending life span by 23.4% and 31.3%, respectively. The stem cell therapy increased the concentration of acetylcholine and recovered neurotrophic factors in the brain and muscles, leading to restoration of microtubule-associated protein 2, cholinergic and dopaminergic nervous systems, microvessels, muscle mass, and antioxidative capacity. The results indicate that repeated transplantation of AMMSCs and ADMSCs elongate both health span and life span, which could be a starting point for antiaging or rejuvenation effects of allogeneic or autologous stem cells with minimum immune rejection. This study demonstrates that repeated treatment with stem cells in normal animals has antiaging potential, extending health span and life span. Because antiaging and prolonged life span are issues currently of interest, these results are significant for readers and investigators. ©AlphaMed Press.

Temporal and spatial changes of cells positive for stem-like markers in different compartments and stages of human colorectal adenoma-carcinoma sequence

PubMed Central

Cui, Guanglin; Xu, Gang; Zhu, Li; Pang, Zhigang; Zheng, Wei; Li, Zhenfeng; Yuan, Aping

2017-01-01

Considerable evidence supports the idea that stem-like cells may play an essential role during the development of colorectal cancer (CRC). To accomplish this aim, we use immunohistochemistry (IHC) and double IHC with different potential stem-like markers, anti-musashi (Msi), anti-CD133, anti- LGR5 and anti-ALDH1 to examine the presentation of stem-like cells in different compartments including adenoma/CRC epithelium, transitional crypts and tumor stroma in colorectal adenoma and CRC. The results showed that cells positive for stem-like markers were remarkably increased in number and frequently observed in the adenoma/CRC epithelium, transitional crypts and tumor stroma. Notably, the population of cells positive for stem-liker markers was expanded from the base to the middle part of the transitional crypt in both adenoma and CRC tissues, reflecting that stem-like cells are likely involved in the process of colorectal tumorigenesis. Counting results showed that the grading scores of cells positive for LGR5 and ALDH1 in the adenoma/CRC epithelium were significantly increased relative with the control epithelium, and associated with the degree of dysplasia in the adenoma and node involvement in the CRC (all P < 0.05). In addition, the density of cells positive for stem–like markers in the adenomatous/cancerous stroma was also increased and paralleled an increase in the density of proliferative stromal cells labeled by PCNA, which were primarily identified as vimentin positive fibroblasts. Our results have revealed a changed temporal and spatial presentation of stem-like markers in different stages of human colorectal adenoma-carcinoma sequence, which might be a hallmark of the adenoma-carcinoma transition. PMID:28484082

IDH1R132H in Neural Stem Cells: Differentiation Impaired by Increased Apoptosis

PubMed Central

Rosiak, Kamila; Smolarz, Maciej; Stec, Wojciech J.; Peciak, Joanna; Grzela, Dawid; Winiecka-Klimek, Marta; Stoczynska-Fidelus, Ewelina; Krynska, Barbara; Piaskowski, Sylwester; Rieske, Piotr

2016-01-01

Background The high frequency of mutations in the isocitrate dehydrogenase 1 (IDH1) gene in diffuse gliomas indicates its importance in the process of gliomagenesis. These mutations result in loss of the normal function and acquisition of the neomorphic activity converting α-ketoglutarate to 2-hydroxyglutarate. This potential oncometabolite may induce the epigenetic changes, resulting in the deregulated expression of numerous genes, including those related to the differentiation process or cell survivability. Methods Neural stem cells were derived from human induced pluripotent stem cells following embryoid body formation. Neural stem cells transduced with mutant IDH1R132H, empty vector, non-transduced and overexpressing IDH1WT controls were differentiated into astrocytes and neurons in culture. The neuronal and astrocytic differentiation was determined by morphology and expression of lineage specific markers (MAP2, Synapsin I and GFAP) as determined by real-time PCR and immunocytochemical staining. Apoptosis was evaluated by real-time observation of Caspase-3 activation and measurement of PARP cleavage by Western Blot. Results Compared with control groups, cells expressing IDH1R132H retained an undifferentiated state and lacked morphological changes following stimulated differentiation. The significant inhibitory effect of IDH1R132H on neuronal and astrocytic differentiation was confirmed by immunocytochemical staining for markers of neural stem cells. Additionally, real-time PCR indicated suppressed expression of lineage markers. High percentage of apoptotic cells was detected within IDH1R132H-positive neural stem cells population and their derivatives, if compared to normal neural stem cells and their derivatives. The analysis of PARP and Caspase-3 activity confirmed apoptosis sensitivity in mutant protein-expressing neural cells. Conclusions Our study demonstrates that expression of IDH1R132H increases apoptosis susceptibility of neural stem cells and their derivatives. Robust apoptosis causes differentiation deficiency of IDH1R132H-expressing cells. PMID:27145078

Imaging transplanted stem cells in real time using an MRI dual-contrast method

PubMed Central

Ngen, Ethel J.; Wang, Lee; Kato, Yoshinori; Krishnamachary, Balaji; Zhu, Wenlian; Gandhi, Nishant; Smith, Barbara; Armour, Michael; Wong, John; Gabrielson, Kathleen; Artemov, Dmitri

2015-01-01

Stem cell therapies are currently being investigated for the repair of brain injuries. Although exogenous stem cell labelling with superparamagnetic iron oxide nanoparticles (SPIONs) prior to transplantation provides a means to noninvasively monitor stem cell transplantation by magnetic resonance imaging (MRI), monitoring cell death is still a challenge. Here, we investigate the feasibility of using an MRI dual-contrast technique to detect cell delivery, cell migration and cell death after stem cell transplantation. Human mesenchymal stem cells were dual labelled with SPIONs and gadolinium-based chelates (GdDTPA). The viability, proliferation rate, and differentiation potential of the labelled cells were then evaluated. The feasibility of this MRI technique to distinguish between live and dead cells was next evaluated using MRI phantoms, and in vivo using both immune-competent and immune-deficient mice, following the induction of brain injury in the mice. All results were validated with bioluminescence imaging. In live cells, a negative (T2/T2*) MRI contrast predominates, and is used to track cell delivery and cell migration. Upon cell death, a diffused positive (T1) MRI contrast is generated in the vicinity of the dead cells, and serves as an imaging marker for cell death. Ultimately, this technique could be used to manage stem cell therapies. PMID:26330231

Imaging transplanted stem cells in real time using an MRI dual-contrast method.

PubMed

Ngen, Ethel J; Wang, Lee; Kato, Yoshinori; Krishnamachary, Balaji; Zhu, Wenlian; Gandhi, Nishant; Smith, Barbara; Armour, Michael; Wong, John; Gabrielson, Kathleen; Artemov, Dmitri

2015-09-02

Stem cell therapies are currently being investigated for the repair of brain injuries. Although exogenous stem cell labelling with superparamagnetic iron oxide nanoparticles (SPIONs) prior to transplantation provides a means to noninvasively monitor stem cell transplantation by magnetic resonance imaging (MRI), monitoring cell death is still a challenge. Here, we investigate the feasibility of using an MRI dual-contrast technique to detect cell delivery, cell migration and cell death after stem cell transplantation. Human mesenchymal stem cells were dual labelled with SPIONs and gadolinium-based chelates (GdDTPA). The viability, proliferation rate, and differentiation potential of the labelled cells were then evaluated. The feasibility of this MRI technique to distinguish between live and dead cells was next evaluated using MRI phantoms, and in vivo using both immune-competent and immune-deficient mice, following the induction of brain injury in the mice. All results were validated with bioluminescence imaging. In live cells, a negative (T2/T2*) MRI contrast predominates, and is used to track cell delivery and cell migration. Upon cell death, a diffused positive (T1) MRI contrast is generated in the vicinity of the dead cells, and serves as an imaging marker for cell death. Ultimately, this technique could be used to manage stem cell therapies.

Apigenin inhibited hypoxia induced stem cell marker expression in a head and neck squamous cell carcinoma cell line.

PubMed

Ketkaew, Yuwaporn; Osathanon, Thanaphum; Pavasant, Prasit; Sooampon, Sireerat

2017-02-01

Cancer stem cells contribute to tumor recurrence, and a hypoxic environment is critical for maintaining cancer stem cells. Apigenin is a natural product with anticancer activity. However, the effect of apigenin on cancer stem cells remains unclear. Our aim was to investigate the effect of apigenin on cancer stem cell marker expression in head and neck squamous cell carcinoma cells under hypoxia. We used three head and neck squamous cell carcinoma cell lines; HN-8, HN-30, and HSC-3. The mRNA expression of cancer stem cell markers was determined by semiquantitative RT-PCR and Real-time PCR. The cytotoxic effect of apigenin was determined by MTT colorimetric assay. Flow cytometry was used to reveal the number of cells expressing cancer stem cell surface markers. HN-30 cells, a cancer cell line from the pharynx, showed the greatest response to hypoxia by increasing their expression of CD44, CD105, NANOG, OCT-4, REX-1, and VEGF. Apigenin significantly decreased HN-30 cell viability in dose- and time-dependent manners. In addition, 40μM apigenin significantly down-regulated the mRNA expression of CD44, NANOG, and CD105. Consistent with these results, the hypoxia-induced increase in CD44 + cells, CD105 + cells, and STRO-1 + cells was significantly abolished by apigenin. Apigenin suppresses cancer stem cell marker expression and the number of cells expressing cell surface markers under hypoxia. Copyright © 2016 Elsevier Ltd. All rights reserved.

Stem cells in degenerative orthopaedic pathologies: effects of aging on therapeutic potential.

PubMed

Atesok, Kivanc; Fu, Freddie H; Sekiya, Ichiro; Stolzing, Alexandra; Ochi, Mitsuo; Rodeo, Scott A

2017-02-01

The purpose of this study was to summarize the current evidence on the use of stem cells in the elderly population with degenerative orthopaedic pathologies and to highlight the pathophysiologic mechanisms behind today's therapeutic challenges in stem cell-based regeneration of destructed tissues in the elderly patients with osteoarthritis (OA), degenerative disc disease (DDD), and tendinopathies. Clinical and basic science studies that report the use of stem cells in the elderly patients with OA, DDD, and tendinopathies were identified using a PubMed search. The studies published in English have been assessed, and the best and most recent evidence was included in the current study. Evidence suggests that, although short-term results regarding the effects of stem cell therapy in degenerative orthopaedic pathologies can be promising, stem cell therapies do not appear to reverse age-related tissue degeneration. Causes of suboptimal outcomes can be attributed to the decrease in the therapeutic potential of aged stem cell populations and the regenerative capacity of these cells, which might be negatively influenced in an aged microenvironment within the degenerated tissues of elderly patients with OA, DDD, and tendinopathies. Clinical protocols guiding the use of stem cells in the elderly patient population are still under development, and high-level randomized controlled trials with long-term outcomes are lacking. Understanding the consequences of age-related changes in stem cell function and responsiveness of the in vivo microenvironment to stem cells is critical when designing cell-based therapies for elderly patients with degenerative orthopaedic pathologies.

CD133(+)/CD44(+)/Oct4(+)/Nestin(+) stem-like cells isolated from Panc-1 cell line may contribute to multi-resistance and metastasis of pancreatic cancer.

PubMed

Wang, Dongqing; Zhu, Haitao; Zhu, Ying; Liu, Yanfang; Shen, Huiling; Yin, Ruigen; Zhang, Zhijian; Su, Zhaoliang

2013-05-01

Pancreatic cancer is an aggressive malignant disease. Owing to the lack of early symptoms, accompanied by extensive metastasis and high resistance to chemotherapy, pancreatic adenocarcinoma becomes the fourth leading cause of cancer-related deaths. In this study, we identified a subpopulation of cells isolated from the Panc-1 cell line and named pancreatic cancer stem-like cells. These Panc-1 stem-like cells expressed high levels of CD133/CD44/Oct4/Nestin. Compared to Panc-1 cells, Panc-1 stem-like cells were resistant to gemcitabine and expressed high levels of MDR1; furthermore, Panc-1 stem-like cells have high anti-apoptotic, but weak proliferative potential. These results indicated that Panc-1 stem-like cells, as a novel group, may be a potential major cause of pancreatic cancer multidrug resistance and extensive metastasis. Copyright © 2012 Elsevier GmbH. All rights reserved.

Induced Pluripotent Stem Cells for Disease Modeling and Evaluation of Therapeutics for Niemann-Pick Disease Type A.

PubMed

Long, Yan; Xu, Miao; Li, Rong; Dai, Sheng; Beers, Jeanette; Chen, Guokai; Soheilian, Ferri; Baxa, Ulrich; Wang, Mengqiao; Marugan, Juan J; Muro, Silvia; Li, Zhiyuan; Brady, Roscoe; Zheng, Wei

2016-12-01

: Niemann-Pick disease type A (NPA) is a lysosomal storage disease caused by mutations in the SMPD1 gene that encodes acid sphingomyelinase (ASM). Deficiency in ASM function results in lysosomal accumulation of sphingomyelin and neurodegeneration. Currently, there is no effective treatment for NPA. To accelerate drug discovery for treatment of NPA, we generated induced pluripotent stem cells from two patient dermal fibroblast lines and differentiated them into neural stem cells. The NPA neural stem cells exhibit a disease phenotype of lysosomal sphingomyelin accumulation and enlarged lysosomes. By using this disease model, we also evaluated three compounds that reportedly reduced lysosomal lipid accumulation in Niemann-Pick disease type C as well as enzyme replacement therapy with ASM. We found that α-tocopherol, δ-tocopherol, hydroxypropyl-β-cyclodextrin, and ASM reduced sphingomyelin accumulation and enlarged lysosomes in NPA neural stem cells. Therefore, the NPA neural stem cells possess the characteristic NPA disease phenotype that can be ameliorated by tocopherols, cyclodextrin, and ASM. Our results demonstrate the efficacies of cyclodextrin and tocopherols in the NPA cell-based model. Our data also indicate that the NPA neural stem cells can be used as a new cell-based disease model for further study of disease pathophysiology and for high-throughput screening to identify new lead compounds for drug development. Currently, there is no effective treatment for Niemann-Pick disease type A (NPA). To accelerate drug discovery for treatment of NPA, NPA-induced pluripotent stem cells were generated from patient dermal fibroblasts and differentiated into neural stem cells. By using the differentiated NPA neuronal cells as a cell-based disease model system, α-tocopherol, δ-tocopherol, and hydroxypropyl-β-cyclodextrin significantly reduced sphingomyelin accumulation in these NPA neuronal cells. Therefore, this cell-based NPA model can be used for further study of disease pathophysiology and for high-throughput screening of compound libraries to identify lead compounds for drug development. ©AlphaMed Press.

RNA-Sequencing Gene Expression Profiling of Orbital Adipose-Derived Stem Cell Population Implicate HOX Genes and WNT Signaling Dysregulation in the Pathogenesis of Thyroid-Associated Orbitopathy

PubMed Central

Tao, Wensi; Ayala-Haedo, Juan A.; Field, Matthew G.; Pelaez, Daniel; Wester, Sara T.

2017-01-01

Purpose The purpose of this study was to characterize the intrinsic cellular properties of orbital adipose-derived stem cells (OASC) from patients with thyroid-associated orbitopathy (TAO) and healthy controls. Methods Orbital adipose tissue was collected from a total of nine patients: four controls and five patients with TAO. Isolated OASC were characterized with mesenchymal stem cell–specific markers. Orbital adipose-derived stem cells were differentiated into three lineages: chondrocytes, osteocytes, and adipocytes. Reverse transcription PCR of genes involved in the adipogenesis, chondrogenesis, and osteogenesis pathways were selected to assay the differentiation capacities. RNA sequencing analysis (RNA-seq) was performed and results were compared to assess for differences in gene expression between TAO and controls. Selected top-ranked results were confirmed by RT-PCR. Results Orbital adipose-derived stem cells isolated from orbital fat expressed high levels of mesenchymal stem cell markers, but low levels of the pluripotent stem cell markers. Orbital adipose-derived stem cells isolated from TAO patients exhibited an increase in adipogenesis, and a decrease in chondrogenesis and osteogenesis. RNA-seq disclosed 54 differentially expressed genes. In TAO OASC, expression of early neural crest progenitor marker (WNT signaling, ZIC genes and MSX2) was lost. Meanwhile, ectopic expression of HOXB2 and HOXB3 was found in the OASC from TAO. Conclusion Our results suggest that there are intrinsic genetic and cellular differences in the OASC populations derived from TAO patients. The upregulation in adipogenesis in OASC of TAO may be is consistent with the clinical phenotype. Downregulation of early neural crest markers and ectopic expression of HOXB2 and HOXB3 in TAO OASC demonstrate dysregulation of developmental and tissue patterning pathways. PMID:29214313

Stem cell-based gene therapy activated using magnetic hyperthermia to enhance the treatment of cancer

PubMed Central

Yin, Perry T.; Shah, Shreyas; Pasquale, Nicholas J.; Garbuzenko, Olga B.; Minko, Tamara; Lee, Ki-Bum

2015-01-01

Stem cell-based gene therapies, wherein stem cells are genetically engineered to express therapeutic molecules, have shown tremendous potential for cancer applications owing to their innate ability to home to tumors. However, traditional stem cell-based gene therapies are hampered by our current inability to control when the therapeutic genes are actually turned on, thereby resulting in detrimental side effects. Here, we report the novel application of magnetic core-shell nanoparticles for the dual purpose of delivering and activating a heat-inducible gene vector that encodes TNF-related apoptosis-inducing ligand (TRAIL) in adipose-derived mesenchymal stem cells (AD-MSCs). By combining the tumor tropism of the AD-MSCs with the spatiotemporal MCNP-based delivery and activation of TRAIL expression, this platform provides an attractive means with which to enhance our control over the activation of stem cell-based gene therapies. In particular, we found that these engineered AD-MSCs retained their innate ability to proliferate, differentiate, and, most importantly, home to tumors, making them ideal cellular carriers. Moreover, exposure of the engineered AD-MSCS to mild magnetic hyperthermia resulted in the selective expression of TRAIL from the engineered AD-MSCs and, as a result, induced significant ovarian cancer cell death in vitro and in vivo. PMID:26720500

Stem cell-based gene therapy activated using magnetic hyperthermia to enhance the treatment of cancer.

PubMed

Yin, Perry T; Shah, Shreyas; Pasquale, Nicholas J; Garbuzenko, Olga B; Minko, Tamara; Lee, Ki-Bum

2016-03-01

Stem cell-based gene therapies, wherein stem cells are genetically engineered to express therapeutic molecules, have shown tremendous potential for cancer applications owing to their innate ability to home to tumors. However, traditional stem cell-based gene therapies are hampered by our current inability to control when the therapeutic genes are actually turned on, thereby resulting in detrimental side effects. Here, we report the novel application of magnetic core-shell nanoparticles for the dual purpose of delivering and activating a heat-inducible gene vector that encodes TNF-related apoptosis-inducing ligand (TRAIL) in adipose-derived mesenchymal stem cells (AD-MSCs). By combining the tumor tropism of the AD-MSCs with the spatiotemporal MCNP-based delivery and activation of TRAIL expression, this platform provides an attractive means with which to enhance our control over the activation of stem cell-based gene therapies. In particular, we found that these engineered AD-MSCs retained their innate ability to proliferate, differentiate, and, most importantly, home to tumors, making them ideal cellular carriers. Moreover, exposure of the engineered AD-MSCS to mild magnetic hyperthermia resulted in the selective expression of TRAIL from the engineered AD-MSCs and, as a result, induced significant ovarian cancer cell death in vitro and in vivo. Copyright © 2015 Elsevier Ltd. All rights reserved.

Nano Let‑7b sensitization of eliminating esophageal cancer stem‑like cells is dependent on blockade of Wnt activation of symmetric division.

PubMed

Pang, Yamei; Liu, Jian; Li, Xiang; Zhang, Yiwen; Zhang, Boxiang; Zhang, Jing; Du, Ning; Xu, Chongwen; Liang, Rui; Ren, Hong; Tang, Shou-Ching; Sun, Xin

2017-10-01

The poor therapy response and poor prognosis of esophageal cancer has made it one of the most malignant carcinoma, and the complicated multidisciplinary treatment failed to achieve a long-term disease-free survival. To diagnose esophageal cancer at an earlier stage, and to improve the effect of anticancer therapy would improve the therapeutic efficacy. After retrospective analysis of the cancer samples of patients who received esophagectomy, we found the relevance between ratio of either ALDH1 or CD133-positive cancer stem cells and 2-year recurrence. Higher ratios of cancer stem cells indicated later clinical stages, and Wnt signaling activation was more frequent in later esophageal carcinoma. Further in bench studies, we explored the suppressive roles and the mechanisms involved in Let‑7 on self-renewal in ECA‑109 and ECA‑9706 esophageal cancer stem cells. Isolated cancer stem cells naturally divide symmetrically and are therapy resistant. Therapy of fluorouracil and docetaxel both enriched the stem cells, proving the resistant characteristics of cancer stem cells. Wnt activation stimulated more symmetric division of stem cells, resulting in self-renewal promotion, which could be blocked by Let‑7 overexpression. Furthermore, enforced Let‑7 sensitized the stem cells to chemotherapies in a Wnt pathway inhibition-dependent manner, contributing to Let‑7 sensitization of chemotherapeutic response. Wnt activation weakened the suppressive Let‑7b through the sponge functions of CCAT-1, forming the negative feedback loop of Let‑7b/Wnt/CCAT1. These results identified the crucial participation of stem cells in esophageal cancer occurrence and progression as the potent indicator, and also indicate the potential powerful agent of Let‑7 nano-particles in treatment of cancer.

Towards a quantitative understanding of stem cell-niche interaction: experiments, models, and technologies.

PubMed

Roeder, Ingo; Loeffler, Markus; Glauche, Ingmar

2011-04-15

Here we report about an interdisciplinary workshop focusing on the effects of the local growth-environment on the regulation of stem cell development. Under the title "Towards a quantitative understanding of stem cell/ niche interaction: Experiments, models, and technologies", 33 experts from eight countries discussed current knowledge, new experimental and theoretical results as well as innovative measurement technologies. Specifically, the workshop addressed the following questions: What defines a stem cell niche? What are functional/regulatory characteristics of stem cell- microenvironment interactions? What experimental systems and technologies for quantifying niche function are available? As a consensus result it was recorded that there is no unique niche architecture across tissues but that there are generic principles of niche organization guaranteeing a proper function of stem cells. This functional aspect, as the major defining criterion, leads to the conclusion that stem cells and their niches need to be considered as an inseparable pair with implications for their experimental assessment: To be able to study any of those two components, the other component has to be accounted for. In this context, a number of classical in vitro assays using co-cultures of stem and stroma cells, but also new, specifically bioengineered culture systems have been discussed with respect to their advantages and disadvantages. Finally, there was a general agreement that the comprehensive understanding of niche-mediated stem cell regulation will, due to the complexity of involved mechanisms, require an interdisciplinary, systems biological approach. In addition to cell and molecular biology, biochemistry, biophysics and bioengineering also bioinformatics and mathematical modeling will play a major role in the future of this field. Copyright © 2011 Elsevier Inc. All rights reserved.

Notch-Dependent Pituitary SOX2+ Stem Cells Exhibit a Timed Functional Extinction in Regulation of the Postnatal Gland

PubMed Central

Zhu, Xiaoyan; Tollkuhn, Jessica; Taylor, Havilah; Rosenfeld, Michael G.

2015-01-01

Summary Although SOX2+ stem cells are present in the postnatal pituitary gland, how they are regulated molecularly and whether they are required for pituitary functions remain unresolved questions. Using a conditional knockout animal model, here we demonstrate that ablation of the canonical Notch signaling in the embryonic pituitary gland leads to progressive depletion of the SOX2+ stem cells and hypoplastic gland. Furthermore, we show that the SOX2+ stem cells initially play a significant role in contributing to postnatal pituitary gland expansion by self-renewal and differentiating into distinct lineages in the immediate postnatal period. However, we found that within several weeks postpartum, the SOX2+ stem cells switch to an essentially dormant state and are no longer required for homeostasis/tissue adaptation. Our results present a dynamic tissue homeostatic model in which stem cells provide an initial contribution to the growth of the neonatal pituitary gland, whereas the mature gland can be maintained in a stem cell-independent fashion. PMID:26651607

Conserved functional antagonism of CELF and MBNL proteins controls stem cell-specific alternative splicing in planarians

PubMed Central

Solana, Jordi; Irimia, Manuel; Ayoub, Salah; Orejuela, Marta Rodriguez; Zywitza, Vera; Jens, Marvin; Tapial, Javier; Ray, Debashish; Morris, Quaid; Hughes, Timothy R; Blencowe, Benjamin J; Rajewsky, Nikolaus

2016-01-01

In contrast to transcriptional regulation, the function of alternative splicing (AS) in stem cells is poorly understood. In mammals, MBNL proteins negatively regulate an exon program specific of embryonic stem cells; however, little is known about the in vivo significance of this regulation. We studied AS in a powerful in vivo model for stem cell biology, the planarian Schmidtea mediterranea. We discover a conserved AS program comprising hundreds of alternative exons, microexons and introns that is differentially regulated in planarian stem cells, and comprehensively identify its regulators. We show that functional antagonism between CELF and MBNL factors directly controls stem cell-specific AS in planarians, placing the origin of this regulatory mechanism at the base of Bilaterians. Knockdown of CELF or MBNL factors lead to abnormal regenerative capacities by affecting self-renewal and differentiation sets of genes, respectively. These results highlight the importance of AS interactions in stem cell regulation across metazoans. DOI: http://dx.doi.org/10.7554/eLife.16797.001 PMID:27502555

Human neural progenitor cells retain viability, phenotype, proliferation, and lineage differentiation when labeled with a novel iron oxide nanoparticle, Molday ION Rhodamine B

PubMed Central

Shen, Wei-Bin; Plachez, Celine; Chan, Amanda; Yarnell, Deborah; Puche, Adam C; Fishman, Paul S; Yarowsky, Paul

2013-01-01

Ultrasmall superparamagnetic iron-oxide particles (USPIOs) loaded into stem cells have been suggested as a way to track stem cell transplantation with magnetic resonance imaging, but the labeling, and post-labeling proliferation, viability, differentiation, and retention of USPIOs within the stem cells have yet to be determined for each type of stem cell and for each type of USPIO. Molday ION Rhodamine B™ (BioPAL, Worcester, MA, USA) (MIRB) has been shown to be a USPIO labeling agent for mesenchymal stem cells, glial progenitor cells, and stem cell lines. In this study, we have evaluated MIRB labeling in human neuroprogenitor cells and found that human neuroprogenitor cells are effectively labeled with MIRB without use of transfection reagents. Viability, proliferation, and differentiation properties are unchanged between MIRB-labeled neuroprogenitors cells and unlabeled cells. Moreover, MIRB-labeled human neuroprogenitor cells can be frozen, thawed, and replated without loss of MIRB or even without loss of their intrinsic biology. Overall, those results show that MIRB has advantageous properties that can be used for cell-based therapy. PMID:24348036

The cell fate determinant Scribble is required for maintenance of hematopoietic stem cell function.

PubMed

Mohr, Juliane; Dash, Banaja P; Schnoeder, Tina M; Wolleschak, Denise; Herzog, Carolin; Tubio Santamaria, Nuria; Weinert, Sönke; Godavarthy, Sonika; Zanetti, Costanza; Naumann, Michael; Hartleben, Björn; Huber, Tobias B; Krause, Daniela S; Kähne, Thilo; Bullinger, Lars; Heidel, Florian H

2018-05-01

Cell fate determinants influence self-renewal potential of hematopoietic stem cells. Scribble and Llgl1 belong to the Scribble polarity complex and reveal tumor-suppressor function in drosophila. In hematopoietic cells, genetic inactivation of Llgl1 leads to expansion of the stem cell pool and increases self-renewal capacity without conferring malignant transformation. Here we show that genetic inactivation of its putative complex partner Scribble results in functional impairment of hematopoietic stem cells (HSC) over serial transplantation and during stress. Although loss of Scribble deregulates transcriptional downstream effectors involved in stem cell proliferation, cell signaling, and cell motility, these effectors do not overlap with transcriptional targets of Llgl1. Binding partner analysis of Scribble in hematopoietic cells using affinity purification followed by mass spectometry confirms its role in cell signaling and motility but not for binding to polarity modules described in drosophila. Finally, requirement of Scribble for self-renewal capacity also affects leukemia stem cell function. Thus, Scribble is a regulator of adult HSCs, essential for maintenance of HSCs during phases of cell stress.

Functional characterization of human pluripotent stem cell-derived arterial endothelial cells.

PubMed

Zhang, Jue; Chu, Li-Fang; Hou, Zhonggang; Schwartz, Michael P; Hacker, Timothy; Vickerman, Vernella; Swanson, Scott; Leng, Ning; Nguyen, Bao Kim; Elwell, Angela; Bolin, Jennifer; Brown, Matthew E; Stewart, Ron; Burlingham, William J; Murphy, William L; Thomson, James A

2017-07-25

Here, we report the derivation of arterial endothelial cells from human pluripotent stem cells that exhibit arterial-specific functions in vitro and in vivo. We combine single-cell RNA sequencing of embryonic mouse endothelial cells with an EFNB2-tdTomato/EPHB4-EGFP dual reporter human embryonic stem cell line to identify factors that regulate arterial endothelial cell specification. The resulting xeno-free protocol produces cells with gene expression profiles, oxygen consumption rates, nitric oxide production levels, shear stress responses, and TNFα-induced leukocyte adhesion rates characteristic of arterial endothelial cells. Arterial endothelial cells were robustly generated from multiple human embryonic and induced pluripotent stem cell lines and have potential applications for both disease modeling and regenerative medicine.

Skeletal tissue engineering using mesenchymal or embryonic stem cells: clinical and experimental data.

PubMed

Gamie, Zakareya; MacFarlane, Robert J; Tomkinson, Alicia; Moniakis, Alexandros; Tran, Gui Tong; Gamie, Yehya; Mantalaris, Athanasios; Tsiridis, Eleftherios

2014-11-01

Mesenchymal stem cells (MSCs) can be obtained from a wide variety of tissues for bone tissue engineering such as bone marrow, adipose, birth-associated, peripheral blood, periosteum, dental and muscle. MSCs from human fetal bone marrow and embryonic stem cells (ESCs) are also promising cell sources. In vitro, in vivo and clinical evidence was collected using MEDLINE® (1950 to January 2014), EMBASE (1980 to January 2014) and Google Scholar (1980 to January 2014) databases. Enhanced results have been found when combining bone marrow-derived mesenchymal stem cells (BMMSCs) with recently developed scaffolds such as glass ceramics and starch-based polymeric scaffolds. Preclinical studies investigating adipose tissue-derived stem cells and umbilical cord tissue-derived stem cells suggest that they are likely to become promising alternatives. Stem cells derived from periosteum and dental tissues such as the periodontal ligament have an osteogenic potential similar to BMMSCs. Stem cells from human fetal bone marrow have demonstrated superior proliferation and osteogenic differentiation than perinatal and postnatal tissues. Despite ethical concerns and potential for teratoma formation, developments have also been made for the use of ESCs in terms of culture and ideal scaffold.

Stem Cells in Skin Regeneration, Wound Healing, and Their Clinical Applications

PubMed Central

Ojeh, Nkemcho; Pastar, Irena; Tomic-Canic, Marjana; Stojadinovic, Olivera

2015-01-01

The skin is the largest organ of the body and has an array of functions. Skin compartments, epidermis, and hair follicles house stem cells that are indispensable for skin homeostasis and regeneration. These stem cells also contribute to wound repair, resulting in restoration of tissue integrity and function of damaged tissue. Unsuccessful wound healing processes often lead to non-healing wounds. Chronic wounds are caused by depletion of stem cells and a variety of other cellular and molecular mechanisms, many of which are still poorly understood. Current chronic wound therapies are limited, so the search to develop better therapeutic strategies is ongoing. Adult stem cells are gaining recognition as potential candidates for numerous skin pathologies. In this review, we will discuss epidermal and other stem cells present in the skin, and highlight some of the therapeutic applications of epidermal stem cells and other adult stem cells as tools for cell/scaffold-based therapies for non-healing wounds and other skin disorders. We will also discuss emerging concepts and offer some perspectives on how skin tissue-engineered products can be optimized to provide efficacious therapy in cutaneous repair and regeneration. PMID:26512657

Stem Cells in Skin Regeneration, Wound Healing, and Their Clinical Applications.

PubMed

Ojeh, Nkemcho; Pastar, Irena; Tomic-Canic, Marjana; Stojadinovic, Olivera

2015-10-23

The skin is the largest organ of the body and has an array of functions. Skin compartments, epidermis, and hair follicles house stem cells that are indispensable for skin homeostasis and regeneration. These stem cells also contribute to wound repair, resulting in restoration of tissue integrity and function of damaged tissue. Unsuccessful wound healing processes often lead to non-healing wounds. Chronic wounds are caused by depletion of stem cells and a variety of other cellular and molecular mechanisms, many of which are still poorly understood. Current chronic wound therapies are limited, so the search to develop better therapeutic strategies is ongoing. Adult stem cells are gaining recognition as potential candidates for numerous skin pathologies. In this review, we will discuss epidermal and other stem cells present in the skin, and highlight some of the therapeutic applications of epidermal stem cells and other adult stem cells as tools for cell/scaffold-based therapies for non-healing wounds and other skin disorders. We will also discuss emerging concepts and offer some perspectives on how skin tissue-engineered products can be optimized to provide efficacious therapy in cutaneous repair and regeneration.

Conditional mutation of Smc5 in mouse embryonic stem cells perturbs condensin localization and mitotic progression.

PubMed

Pryzhkova, Marina V; Jordan, Philip W

2016-04-15

Correct duplication of stem cell genetic material and its appropriate segregation into daughter cells are requisites for tissue, organ and organism homeostasis. Disruption of stem cell genomic integrity can lead to developmental abnormalities and cancer. Roles of the Smc5/6 structural maintenance of chromosomes complex in pluripotent stem cell genome maintenance have not been investigated, despite its important roles in DNA synthesis, DNA repair and chromosome segregation as evaluated in other model systems. Using mouse embryonic stem cells (mESCs) with a conditional knockout allele of Smc5, we showed that Smc5 protein depletion resulted in destabilization of the Smc5/6 complex, accumulation of cells in G2 phase of the cell cycle and apoptosis. Detailed assessment of mitotic mESCs revealed abnormal condensin distribution and perturbed chromosome segregation, accompanied by irregular spindle morphology, lagging chromosomes and DNA bridges. Mutation of Smc5 resulted in retention of Aurora B kinase and enrichment of condensin on chromosome arms. Furthermore, we observed reduced levels of Polo-like kinase 1 at kinetochores during mitosis. Our study reveals crucial requirements of the Smc5/6 complex during cell cycle progression and for stem cell genome maintenance. © 2016. Published by The Company of Biologists Ltd.

P63 EXPRESSION LEVELS IN SIDE POPULATION AND LOW LIGHT SCATTERING OCULAR SURFACE EPITHELIAL CELLS

PubMed Central

Epstein, Seth P; Wolosin, J. Mario; Asbell, Penny A

2005-01-01

Purpose Because stem cells exhibit high self-renewal capacity, slow cycling, and high proliferative potential, and one of many markers postulated for epithelial stem cells, p63, is challenged by widespread expression within stem cell–free regions, we examined p63 expression in these stem cell–associated cohorts compared with their controls. Methods Rabbit limbocorneal cryosections, cytospun cell-sorted (by fluorescence-activated cell sorter) side population (SP) and low side scatter (LSSC) cells, and limbal epithelial cells over feeders were stained for p63 by indirect immunofluorescence. Clones were fixed and stained daily for 7 days. Image analysis measured p63 intensity, plotting it against colony size. Results All basal limbal cells were positive for p63, yet only 5% to 7% expressed high p63 intensities, 40% intermediate, and the majority low. Side population cells were less than 1% of total cells. The average intensity of SP staining was three times that of controls. Subpopulations displaying stemlike features exhibited highest p63 expression. Replication rates of isolated cells differed. Day 5 colonies contained 256 (16 hours/cycle) to two (96 hours/cycle) cells. Whereas all cells were positive for p63, intensity in slow-cycling cells was three to four times that in rapidly proliferating congeners. Increased cell doublings did not decrease fluorescence. Conclusions Results suggest that p63 concentration is maximal in stem cells and decreases with differentiation. High p63 levels seem to correlate with cells of the SP and LSSC phenotypes, indicating high cell stemness. With identification of stem cells, further studies can elucidate their use in supporting ocular surface health. PMID:17057802

Governing stem cell banks and registries: emerging issues.

PubMed

Isasi, Rosario M; Knoppers, Bartha M

2009-01-01

The expansion of national and international research efforts in stem cell research is increasingly paired with the trend of establishing stem cell banks and registries. In jurisdictions crossing the spectrum of restrictive to liberal stem cell policies, banks and registries are emerging as an essential resource for transnational access to quality-controlled and ethically sourced stem cell lines. In this study, we report the preliminary findings of a survey of stem cell banks participating in the International Stem Cell Forum's International Stem Cell Banking Initiative (ISCBI). The questionnaire circulated to all ISCBI members addressed both general issues surrounding research policies (e.g., national policies regulating the permissibility of conducting embryonic stem cell research (hESCR)) and, more specifically, issues relating to the governance of stem cell banking projects. The results of the questionnaire were complemented by scholarly research conducted by the authors. This article provides an overview of the current international hESC banking landscape (I). For this purpose, the policy and governance approaches adopted in the surveyed stem cell banks at the national level will be analyzed and areas of convergence and variance will be identified (II). It is beyond the scope of this paper to provide a comprehensive analysis of the wide range of possible governance approaches, policy responses, and their implications. However, we want to provide a starting point for discussion surrounding key questions and challenges as concerns provenance, access, and deposit of hESC lines (III). Finally, while our analysis is focused on research grade hESCs, the lessons to be gleaned from this examination will encourage further thought, analysis, and research into the issues raised in the banking and governance of other sources of stem cell lines (e.g., SCNT, parthenogenesis, iPs) (IV).

Targeted inactivation of integrin-linked kinase in hair follicle stem cells reveals an important modulatory role in skin repair after injury.

PubMed

Nakrieko, Kerry-Ann; Rudkouskaya, Alena; Irvine, Timothy S; D'Souza, Sudhir J A; Dagnino, Lina

2011-07-15

Integrin-linked kinase (ILK) is key for normal epidermal morphogenesis, but little is known about its role in hair follicle stem cells and epidermal regeneration. Hair follicle stem cells are important contributors to newly formed epidermis following injury. We inactivated the Ilk gene in the keratin 15--expressing stem cell population of the mouse hair follicle bulge. Loss of ILK expression in these cells resulted in impaired cutaneous wound healing, with substantially decreased wound closure rates. ILK-deficient stem cells produced very few descendants that moved toward the epidermal surface and into the advancing epithelium that covers the wound. Furthermore, those few mutant cells that homed in the regenerated epidermis exhibited a reduced residence time. Paradoxically, ILK-deficient bulge stem cells responded to anagen growth signals and contributed to newly regenerated hair follicles during this phase of hair follicle growth. Thus ILK plays an important modulatory role in the normal contribution of hair follicle stem cell progeny to the regenerating epidermis following injury.

Targeted inactivation of integrin-linked kinase in hair follicle stem cells reveals an important modulatory role in skin repair after injury

PubMed Central

Nakrieko, Kerry-Ann; Rudkouskaya, Alena; Irvine, Timothy S.; D'souza, Sudhir J. A.; Dagnino, Lina

2011-01-01

Integrin-linked kinase (ILK) is key for normal epidermal morphogenesis, but little is known about its role in hair follicle stem cells and epidermal regeneration. Hair follicle stem cells are important contributors to newly formed epidermis following injury. We inactivated the Ilk gene in the keratin 15–expressing stem cell population of the mouse hair follicle bulge. Loss of ILK expression in these cells resulted in impaired cutaneous wound healing, with substantially decreased wound closure rates. ILK-deficient stem cells produced very few descendants that moved toward the epidermal surface and into the advancing epithelium that covers the wound. Furthermore, those few mutant cells that homed in the regenerated epidermis exhibited a reduced residence time. Paradoxically, ILK-deficient bulge stem cells responded to anagen growth signals and contributed to newly regenerated hair follicles during this phase of hair follicle growth. Thus ILK plays an important modulatory role in the normal contribution of hair follicle stem cell progeny to the regenerating epidermis following injury. PMID:21593206

A novel intranuclear RNA vector system for long-term stem cell modification

PubMed Central

Ikeda, Yasuhiro; Makino, Akiko; Matchett, William E.; Holditch, Sara J.; Lu, Brian; Dietz, Allan B.; Tomonaga, Keizo

2015-01-01

Genetically modified stem and progenitor cells have emerged as a promising regenerative platform in the treatment of genetic and degenerative disorders, highlighted by their successful therapeutic use in inherent immunodeficiencies. However, biosafety concerns over insertional mutagenesis resulting from integrating recombinant viral vectors have overshadowed the widespread clinical applications of genetically modified stem cells. Here, we report an RNA-based episomal vector system, amenable for long-term transgene expression in stem cells. Specifically, we used a unique intranuclear RNA virus, Borna disease virus (BDV), as the gene transfer vehicle, capable of persistent infections in various cell types. BDV-based vectors allowed for long-term transgene expression in mesenchymal stem cells (MSCs) without affecting cellular morphology, cell surface CD105 expression, or the adipogenicity of MSCs. Similarly, replication-defective BDV vectors achieved long-term transduction of human induced pluripotent stem cells (iPSCs), while maintaining the ability to differentiate into three embryonic germ layers. Thus, the BDV-based vectors offer a genomic modification-free, episomal RNA delivery system for sustained stem cell transduction. PMID:26632671

Representations of stem cell clinics on Twitter.

PubMed

Kamenova, Kalina; Reshef, Amir; Caulfield, Timothy

2014-12-01

The practice of travelling abroad to receive unproven and unregulated stem cell treatments has become an increasingly problematic global phenomenon known as 'stem cell tourism'. In this paper, we examine representations of nine major clinics and providers of such treatments on the microblogging network Twitter. We collected and conducted a content analysis of Twitter posts (n = 363) by these establishments and by other users mentioning them, focusing specifically on marketing claims about treatment procedures and outcomes, discussions of safety and efficacy of stem cell transplants, and specific representations of patients' experiences. Our analysis has shown that there were explicit claims or suggestions of benefits associated with unproven stem cell treatments in approximately one third of the tweets and that patients' experiences, whenever referenced, were presented as invariably positive and as testimonials about the efficacy of stem cell transplants. Furthermore, the results indicated that the tone of most tweets (60.2 %) was overwhelmingly positive and there were rarely critical discussions about significant health risks associated with unproven stem cell therapies. When placed in the context of past research on the problems associated with the marketing of unproven stem cell therapies, this analysis of representations on Twitter suggests that discussions in social media have also remained largely uncritical of the stem cell tourism phenomenon, with inaccurate representations of risks and benefits for patients.

Niche matters: The comparison between bone marrow stem cells and endometrial stem cells and stromal fibroblasts reveal distinct migration and cytokine profiles in response to inflammatory stimulus

PubMed Central

Sorjamaa, Anna; Kangasniemi, Marika; Sutinen, Meeri; Salo, Tuula; Liakka, Annikki; Lehenkari, Petri; Tapanainen, Juha S.; Vuolteenaho, Olli; Chen, Joseph C.; Lehtonen, Siri; Piltonen, Terhi T.

2017-01-01

Objective Intrinsic inflammatory characteristics play a pivotal role in stem cell recruitment and homing through migration where the subsequent change in niche has been shown to alter these characteristics. The bone marrow mesenchymal stem cells (bmMSCs) have been demonstrated to migrate to the endometrium contributing to the stem cell reservoir and regeneration of endometrial tissue. Thus, the aim of the present study was to compare the inflammation-driven migration and cytokine secretion profile of human bmMSCs to endometrial mesenchymal stem cells (eMSCs) and endometrial fibroblasts (eSFs). Materials and methods The bmMSCs were isolated from bone marrow aspirates through culturing, whereas eMSCs and eSFs were FACS-isolated. All cell types were tested for their surface marker, proliferation profiles and migration properties towards serum and inflammatory attractants. The cytokine/chemokine secretion profile of 35 targets was analysed in each cell type at basal level along with lipopolysaccharide (LPS)-induced state. Results Both stem cell types, bmMSCs and eMSCs, presented with similar stem cell surface marker profiles as well as possessed high proliferation and migration potential compared to eSFs. In multiplex assays, the secretion of 16 cytokine targets was detected and LPS stimulation expanded the cytokine secretion pattern by triggering the secretion of several targets. The bmMSCs exhibited higher cytokine secretion of vascular endothelial growth factor (VEGF)-A, stromal cell-derived factor-1 alpha (SDF)-1α, interleukin-1 receptor antagonist (IL-1RA), IL-6, interferon-gamma inducible protein (IP)-10, monocyte chemoattractant protein (MCP)-1, macrophage inflammatory protein (MIP)1α and RANTES compared to eMSCs and/or eSFs after stimulation with LPS. The basal IL-8 secretion was higher in both endometrial cell types compared to bmMSCs. Conclusion Our results highlight that similar to bmMSCs, the eMSCs possess high migration activity while the differentiation process towards stromal fibroblasts seemed to result in loss of stem cell surface markers, minimal migration activity and a subtler cytokine profile likely contributing to normal endometrial function. PMID:28419140

Chemical Activation of the Hypoxia-Inducible Factor Reversibly Reduces Tendon Stem Cell Proliferation, Inhibits Their Differentiation, and Maintains Cell Undifferentiation.

PubMed

Menon, Alessandra; Creo, Pasquale; Piccoli, Marco; Bergante, Sonia; Conforti, Erika; Banfi, Giuseppe; Randelli, Pietro; Anastasia, Luigi

2018-01-01

Adult stem cell-based therapeutic approaches for tissue regeneration have been proposed for several years. However, adult stem cells are usually limited in number and difficult to be expanded in vitro, and they usually tend to quickly lose their potency with passages, as they differentiate and become senescent. Culturing stem cells under reduced oxygen tensions (below 21%) has been proposed as a tool to increase cell proliferation, but many studies reported opposite effects. In particular, cell response to hypoxia seems to be very stem cell type specific. Nonetheless, it is clear that a major role in this process is played by the hypoxia inducible factor (HIF), the master regulator of cell response to oxygen deprivation, which affects cell metabolism and differentiation. Herein, we report that a chemical activation of HIF in human tendon stem cells reduces their proliferation and inhibits their differentiation in a reversible and dose-dependent manner. These results support the notion that hypoxia, by activating HIF, plays a crucial role in preserving stem cells in an undifferentiated state in the "hypoxic niches" present in the tissue in which they reside before migrating in more oxygenated areas to heal a damaged tissue.

Generation of diverse neuronal subtypes in cloned populations of stem-like cells

PubMed Central

Varga, Balázs V; Hádinger, Nóra; Gócza, Elen; Dulberg, Vered; Demeter, Kornél; Madarász, Emília; Herberth, Balázs

2008-01-01

Background The central nervous tissue contains diverse subtypes of neurons with characteristic morphological and physiological features and different neurotransmitter phenotypes. The generation of neurons with defined neurotransmitter phenotypes seems to be governed by factors differently expressed along the anterior-posterior and dorsal-ventral body axes. The mechanisms of the cell-type determination, however, are poorly understood. Selected neuronal phenotypes had been generated from embryonic stem (ES) cells, but similar results were not obtained on more restricted neural stem cells, presumably due to the lack of homogeneous neural stem cell populations as a starting material. Results In the presented work, the establishment of different neurotransmitter phenotypes was investigated in the course of in vitro induced neural differentiation of a one-cell derived neuroectodermal cell line, in conjunction with the activation of various region-specific genes. For comparison, similar studies were carried out on the R1 embryonic stem (ES) and P19 multipotent embryonic carcinoma (EC) cells. In response to a short treatment with all-trans retinoic acid, all cell lines gave rise to neurons and astrocytes. Non-induced neural stem cells and self-renewing cells persisting in differentiated cultures, expressed "stemness genes" along with early embryonic anterior-dorsal positional genes, but did not express the investigated CNS region-specific genes. In differentiating stem-like cell populations, on the other hand, different region-specific genes, those expressed in non-overlapping regions along the body axes were activated. The potential for diverse regional specifications was induced in parallel with the initiation of neural tissue-type differentiation. In accordance with the wide regional specification potential, neurons with different neurotransmitter phenotypes developed. Mechanisms inherent to one-cell derived neural stem cell populations were sufficient to establish glutamatergic and GABAergic neuronal phenotypes but failed to manifest cathecolaminergic neurons. Conclusion The data indicate that genes involved in positional determination are activated along with pro-neuronal genes in conditions excluding any outside influences. Interactions among progenies of one cell derived neural stem cells are sufficient for the activation of diverse region specific genes and initiate different routes of neuronal specification. PMID:18808670

Adipose tissue-derived stem cells enhance bioprosthetic mesh repair of ventral hernias.

PubMed

Altman, Andrew M; Abdul Khalek, Feras J; Alt, Eckhard U; Butler, Charles E

2010-09-01

Bioprosthetic mesh used for ventral hernia repair becomes incorporated into the musculofascial edge by cellular infiltration and vascularization. Adipose tissue-derived stem cells promote tissue repair and vascularization and may increase the rate or degree of tissue incorporation. The authors hypothesized that introducing these cells into bioprosthetic mesh would result in adipose tissue-derived stem cell engraftment and proliferation and enhance incorporation of the bioprosthetic mesh. Adipose tissue-derived stem cells were isolated from the subcutaneous adipose tissue of syngeneic Brown Norway rats, expanded in vitro, and labeled with green fluorescent protein. Thirty-six additional rats underwent inlay ventral hernia repair with porcine acellular dermal matrix. Two 12-rat groups had the cells (1.0 x 10(6)) injected directly into the musculofascial/porcine acellular dermal matrix interface after repair or received porcine acellular dermal matrix on which the cells had been preseeded; the 12-rat control group received no stem cells. At 2 weeks, adipose tissue-derived stem cells in both stem cell groups engrafted, survived, migrated, and proliferated. Mean cellular infiltration into porcine acellular dermal matrix at the musculofascial/graft interface was significantly greater in the preseeded and injected stem cell groups than in the control group. Mean vascular infiltration of the porcine acellular dermal matrix was significantly greater in both stem cell groups than in the control group. Preseeded and injected adipose tissue-derived stem cells engraft, migrate, proliferate, and enhance the vascularity of porcine acellular dermal matrix grafts at the musculofascial/graft interface. These cells can thus enhance incorporation of porcine acellular dermal matrix into the abdominal wall after repair of ventral hernias.

Stem cell research in cell transplantation: sources, geopolitical influence, and transplantation.

PubMed

Eve, David J; Fillmore, Randolph W; Borlongan, Cesar V; Sanberg, Paul R

2010-01-01

If the rapidly progressing field of stem cell research reaches its full potential, successful treatments and enhanced understanding of many diseases are the likely results. However, the full potential of stem cell science will only be reached if all possible avenues can be explored and on a worldwide scale. Until 2009, the US had a highly restrictive policy on obtaining cells from human embryos and fetal tissue, a policy that pushed research toward the use of adult-derived cells. Currently, US policy is still in flux, and retrospective analysis does show the US lagging behind the rest of the world in the proportional increase in embryonic/fetal stem cell research. The majority of US studies being on either a limited number of cell lines, or on cells derived elsewhere (or funded by other sources than Federal) rather than on freshly isolated embryonic or fetal material. Neural, mesenchymal, and the mixed stem cell mononuclear fraction are the most commonly investigated types, which can generally be classified as adult-derived stem cells, although roughly half of the neural stem cells are fetal derived. Other types, such as embryonic and fat-derived stem cells, are increasing in their prominence, suggesting that new types of stem cells are still being pursued. Sixty percent of the reported stem cell studies involved transplantation, of which over three quarters were allogeneic transplants. A high proportion of the cardiovascular systems articles were on allogeneic transplants in a number of different species, including several autologous studies. A number of pharmaceutical grade stem cell products have also recently been tested and reported on. Stem cell research shows considerable promise for the treatment of a number of disorders, some of which have entered clinical trials; over the next few years it will be interesting to see how these treatments progress in the clinic.

High Glucose Inhibits Neural Stem Cell Differentiation Through Oxidative Stress and Endoplasmic Reticulum Stress.

PubMed

Chen, Xi; Shen, Wei-Bin; Yang, Penghua; Dong, Daoyin; Sun, Winny; Yang, Peixin

2018-06-01

Maternal diabetes induces neural tube defects by suppressing neurogenesis in the developing neuroepithelium. Our recent study further revealed that high glucose inhibited embryonic stem cell differentiation into neural lineage cells. However, the mechanism whereby high glucose suppresses neural differentiation is unclear. To investigate whether high glucose-induced oxidative stress and endoplasmic reticulum (ER) stress lead to the inhibition of neural differentiation, the effect of high glucose on neural stem cell (the C17.2 cell line) differentiation was examined. Neural stem cells were cultured in normal glucose (5 mM) or high glucose (25 mM) differentiation medium for 3, 5, and 7 days. High glucose suppressed neural stem cell differentiation by significantly decreasing the expression of the neuron marker Tuj1 and the glial cell marker GFAP and the numbers of Tuj1 + and GFAP + cells. The antioxidant enzyme superoxide dismutase mimetic Tempol reversed high glucose-decreased Tuj1 and GFAP expression and restored the numbers of neurons and glial cells differentiated from neural stem cells. Hydrogen peroxide treatment imitated the inhibitory effect of high glucose on neural stem cell differentiation. Both high glucose and hydrogen peroxide triggered ER stress, whereas Tempol blocked high glucose-induced ER stress. The ER stress inhibitor, 4-phenylbutyrate, abolished the inhibition of high glucose or hydrogen peroxide on neural stem cell differentiation. Thus, oxidative stress and its resultant ER stress mediate the inhibitory effect of high glucose on neural stem cell differentiation.

Differential Gene Expression Profiling of Dystrophic Dog Muscle after MuStem Cell Transplantation

PubMed Central

Babarit, Candice; Larcher, Thibaut; Dubreil, Laurence; Leroux, Isabelle; Zuber, Céline; Ledevin, Mireille; Deschamps, Jack-Yves; Fromes, Yves; Cherel, Yan; Guevel, Laetitia; Rouger, Karl

2015-01-01

Background Several adult stem cell populations exhibit myogenic regenerative potential, thus representing attractive candidates for therapeutic approaches of neuromuscular diseases such as Duchenne Muscular Dystrophy (DMD). We have recently shown that systemic delivery of MuStem cells, skeletal muscle-resident stem cells isolated in healthy dog, generates the remodelling of muscle tissue and gives rise to striking clinical benefits in Golden Retriever Muscular Dystrophy (GRMD) dog. This global effect, which is observed in the clinically relevant DMD animal model, leads us to question here the molecular pathways that are impacted by MuStem cell transplantation. To address this issue, we compare the global gene expression profile between healthy, GRMD and MuStem cell treated GRMD dog muscle, four months after allogenic MuStem cell transplantation. Results In the dystrophic context of the GRMD dog, disease-related deregulation is observed in the case of 282 genes related to various processes such as inflammatory response, regeneration, calcium ion binding, extracellular matrix organization, metabolism and apoptosis regulation. Importantly, we reveal the impact of MuStem cell transplantation on several molecular and cellular pathways based on a selection of 31 genes displaying signals specifically modulated by the treatment. Concomitant with a diffuse dystrophin expression, a histological remodelling and a stabilization of GRMD dog clinical status, we show that cell delivery is associated with an up-regulation of genes reflecting a sustained enhancement of muscle regeneration. We also identify a decreased mRNA expression of a set of genes having metabolic functions associated with lipid homeostasis and energy. Interestingly, ubiquitin-mediated protein degradation is highly enhanced in GRMD dog muscle after systemic delivery of MuStem cells. Conclusions Overall, our results provide the first high-throughput characterization of GRMD dog muscle and throw new light on the complex molecular/cellular effects associated with muscle repair and the clinical efficacy of MuStem cell-based therapy. PMID:25955839

Retracted article: In vitro derivation of mammalian germ cells from stem cells and their potential therapeutic application.

PubMed

Saito, Shigeo; Lin, Ying-Chu; Murayama, Yoshinobu; Nakamura, Yukio; Eckner, Richard; Niemann, Heiner; Yokoyama, Kazunari K

2015-12-01

Pluripotent stem cells (PSCs) are a unique type of cells because they exhibit the characteristics of self-renewal and pluripotency. PSCs may be induced to differentiate into any cell type, even male and female germ cells, suggesting their potential as novel cell-based therapeutic treatment for infertility problems. Spermatogenesis is an intricate biological process that starts from self-renewal of spermatogonial stem cells (SSCs) and leads to differentiated haploid spermatozoa. Errors at any stage in spermatogenesis may result in male infertility. During the past decade, much progress has been made in the derivation of male germ cells from various types of progenitor stem cells. Currently, there are two main approaches for the derivation of functional germ cells from PSCs, either the induction of in vitro differentiation to produce haploid cell products, or combination of in vitro differentiation and in vivo transplantation. The production of mature and fertile spermatozoa from stem cells might provide an unlimited source of autologous gametes for treatment of male infertility. Here, we discuss the current state of the art regarding the differentiation potential of SSCs, embryonic stem cells, and induced pluripotent stem cells to produce functional male germ cells. We also discuss the possible use of livestock-derived PSCs as a novel option for animal reproduction and infertility treatment.

HPV-Induced Field Cancerisation: Transformation of Adult Tissue Stem Cell Into Cancer Stem Cell.

PubMed

Olivero, Carlotta; Lanfredini, Simone; Borgogna, Cinzia; Gariglio, Marisa; Patel, Girish K

2018-01-01

Field cancerisation was originally described as a basis for multiple head and neck squamous cell carcinoma (HNSCC) and is a pre-malignant phenomenon that is frequently attributable to oncogenic human papillomavirus (HPV) infection. Our work on β-HPV-induced cutaneous squamous cell carcinomas identified a novel Lrig1+ hair follicle junctional zone keratinocyte stem cell population as the basis for field cancerisation. Herein, we describe the ability for HPV to infect adult tissue stem cells in order to establish persistent infection and induce their proliferation and displacement resulting in field cancerisation. By review of the HPV literature, we reveal how this mechanism is conserved as the basis of field cancerisation across many tissues. New insights have identified the capacity for HPV early region genes to dysregulate adult tissue stem cell self-renewal pathways ensuring that the expanded population preserve its stem cell characteristics beyond the stem cell niche. HPV-infected cells acquire additional transforming mutations that can give rise to intraepithelial neoplasia (IEN), from environmental factors such as sunlight or tobacco induced mutations in skin and oral cavity, respectively. With establishment of IEN, HPV viral replication is sacrificed with loss of the episome, and the tissue is predisposed to multiple cancer stem cell-driven carcinomas.

HMGA1 silencing reduces stemness and temozolomide resistance in glioblastoma stem cells.

PubMed

Colamaio, Marianna; Tosti, Nadia; Puca, Francesca; Mari, Alessia; Gattordo, Rosaria; Kuzay, Yalçın; Federico, Antonella; Pepe, Anna; Sarnataro, Daniela; Ragozzino, Elvira; Raia, Maddalena; Hirata, Hidenari; Gemei, Marica; Mimori, Koshi; Del Vecchio, Luigi; Battista, Sabrina; Fusco, Alfredo

2016-10-01

Glioblastoma multiforme (GBM) develops from a small subpopulation of stem-like cells, which are endowed with the ability to self-renew, proliferate and give rise to progeny of multiple neuroepithelial lineages. These cells are resistant to conventional chemo- and radiotherapy and are hence also responsible for tumor recurrence. HMGA1 overexpression has been shown to correlate with proliferation, invasion, and angiogenesis of GBMs and to affect self-renewal of cancer stem cells from colon cancer. The role of HMGA1 in GBM tumor stem cells is not completely understood. We have investigated the role of HMGA1 in brain tumor stem cell (BTSC) self-renewal, stemness and resistance to temozolomide by shRNA- mediated HMGA1 silencing. We first report that HMGA1 is overexpressed in a subset of BTSC lines from human GBMs. Then, we show that HMGA1 knockdown reduces self-renewal, sphere forming efficiency and stemness, and sensitizes BTSCs to temozolomide. Interestingly, HMGA1 silencing also leads to reduced tumor initiation ability in vivo. These results demonstrate a pivotal role of HMGA1 in cancer stem cell gliomagenesis and endorse HMGA1 as a suitable target for CSC-specific GBM therapy.

Investigation of the expression of RIF1 gene on head and neck, pancreatic and brain cancer and cancer stem cells.

PubMed

GursesCila, Hacer E; Acar, Muradiye; Barut, Furkan B; Gunduz, Mehmet; Grenman, Reidar; Gunduz, Esra

2016-12-01

Recent studies have shown that cancer stem cells are resistant to chemotherapy. The aim of this study was to compare RIF1 gene expression in head and neck, pancreatic cancer and glioma cell lines and the cancer stem cells isolated from these cell lines. UT-SCC-74 from Turku University and UT-SCC-74B primary tumor metastasis and neck cancer cell lines, YKG-1 glioma cancer cell line from RIKEN, pancreatic cancer cell lines and ASPC-1 cells from ATCC were grown in cell culture. To isolate cancer stem cells, ALDH-1 for UT-SCC-74 and UT-SCC-74B cell line, CD-133 for YKG-1 cell line and CD-24 for ASPC-1 cell line, were used as markers of cancer stem cells. RNA isolation was performed for both cancer lines and cancer stem cells. RNAs were converted to cDNA. RIF1 gene expression was performed by qRT-PCR analysis. RIF1 gene expression was compared with cancer cell lines and cancer stem cells isolated from these cell lines. The possible effect of RIF1 gene was evaluated. In the pancreatic cells, RIF1 gene expression in the stem cell-positive cell line was 256 time that seen in the stem cell-negative cell line. Considering the importance of RIF1 in NHEJ and of NHEJ in pancreatic cancer, RIF1 may be one of the genes that plays an important role in the diagnoses and therapeutic treatment of pancreatic cancer. The results of head and neck and brain cancers are inconclusive and further studies are required to elucidate the connection between RIF1 gene and these other types of cancers.

FoxO is a critical regulator of stem cell maintenance in immortal Hydra.

PubMed

Boehm, Anna-Marei; Khalturin, Konstantin; Anton-Erxleben, Friederike; Hemmrich, Georg; Klostermeier, Ulrich C; Lopez-Quintero, Javier A; Oberg, Hans-Heinrich; Puchert, Malte; Rosenstiel, Philip; Wittlieb, Jörg; Bosch, Thomas C G

2012-11-27

Hydra's unlimited life span has long attracted attention from natural scientists. The reason for that phenomenon is the indefinite self-renewal capacity of its stem cells. The underlying molecular mechanisms have yet to be explored. Here, by comparing the transcriptomes of Hydra's stem cells followed by functional analysis using transgenic polyps, we identified the transcription factor forkhead box O (FoxO) as one of the critical drivers of this continuous self-renewal. foxO overexpression increased interstitial stem cell and progenitor cell proliferation and activated stem cell genes in terminally differentiated somatic cells. foxO down-regulation led to an increase in the number of terminally differentiated cells, resulting in a drastically reduced population growth rate. In addition, it caused down-regulation of stem cell genes and antimicrobial peptide (AMP) expression. These findings contribute to a molecular understanding of Hydra's immortality, indicate an evolutionarily conserved role of FoxO in controlling longevity from Hydra to humans, and have implications for understanding cellular aging.

Stem cell-based therapies for tumors in the brain: are we there yet?

PubMed Central

Shah, Khalid

2016-01-01

Advances in understanding adult stem cell biology have facilitated the development of novel cell-based therapies for cancer. Recent developments in conventional therapies (eg, tumor resection techniques, chemotherapy strategies, and radiation therapy) for treating both metastatic and primary tumors in the brain, particularly glioblastoma have not resulted in a marked increase in patient survival. Preclinical studies have shown that multiple stem cell types exhibit inherent tropism and migrate to the sites of malignancy. Recent studies have validated the feasibility potential of using engineered stem cells as therapeutic agents to target and eliminate malignant tumor cells in the brain. This review will discuss the recent progress in the therapeutic potential of stem cells for tumors in the brain and also provide perspectives for future preclinical studies and clinical translation. PMID:27282399

Kidney specific protein-positive cells derived from embryonic stem cells reproduce tubular structures in vitro and differentiate into renal tubular cells.

PubMed

Morizane, Ryuji; Monkawa, Toshiaki; Fujii, Shizuka; Yamaguchi, Shintaro; Homma, Koichiro; Matsuzaki, Yumi; Okano, Hideyuki; Itoh, Hiroshi

2014-01-01

Embryonic stem cells and induced pluripotent stem cells have the ability to differentiate into various organs and tissues, and are regarded as new tools for the elucidation of disease mechanisms as well as sources for regenerative therapies. However, a method of inducing organ-specific cells from pluripotent stem cells is urgently needed. Although many scientists have been developing methods to induce various organ-specific cells from pluripotent stem cells, renal lineage cells have yet to be induced in vitro because of the complexity of kidney structures and the diversity of kidney-component cells. Here, we describe a method of inducing renal tubular cells from mouse embryonic stem cells via the cell purification of kidney specific protein (KSP)-positive cells using an anti-KSP antibody. The global gene expression profiles of KSP-positive cells derived from ES cells exhibited characteristics similar to those of cells in the developing kidney, and KSP-positive cells had the capacity to form tubular structures resembling renal tubular cells when grown in a 3D culture in Matrigel. Moreover, our results indicated that KSP-positive cells acquired the characteristics of each segment of renal tubular cells through tubular formation when stimulated with Wnt4. This method is an important step toward kidney disease research using pluripotent stem cells, and the development of kidney regeneration therapies.

Pipette-based Method to Study Embryoid Body Formation Derived from Mouse and Human Pluripotent Stem Cells Partially Recapitulating Early Embryonic Development Under Simulated Microgravity Conditions

NASA Astrophysics Data System (ADS)

Shinde, Vaibhav; Brungs, Sonja; Hescheler, Jürgen; Hemmersbach, Ruth; Sachinidis, Agapios

2016-06-01

The in vitro differentiation of pluripotent stem cells partially recapitulates early in vivo embryonic development. More recently, embryonic development under the influence of microgravity has become a primary focus of space life sciences. In order to integrate the technique of pluripotent stem cell differentiation with simulated microgravity approaches, the 2-D clinostat compatible pipette-based method was experimentally investigated and adapted for investigating stem cell differentiation processes under simulated microgravity conditions. In order to keep residual accelerations as low as possible during clinorotation, while also guaranteeing enough material for further analysis, stem cells were exposed in 1-mL pipettes with a diameter of 3.5 mm. The differentiation of mouse and human pluripotent stem cells inside the pipettes resulted in the formation of embryoid bodies at normal gravity (1 g) after 24 h and 3 days. Differentiation of the mouse pluripotent stem cells on a 2-D pipette-clinostat for 3 days also resulted in the formation of embryoid bodies. Interestingly, the expression of myosin heavy chain was downregulated when cultivation was continued for an additional 7 days at normal gravity. This paper describes the techniques for culturing and differentiation of pluripotent stem cells and exposure to simulated microgravity during culturing or differentiation on a 2-D pipette clinostat. The implementation of these methodologies along with -omics technologies will contribute to understand the mechanisms regulating how microgravity influences early embryonic development.

RNA-Sequencing Gene Expression Profiling of Orbital Adipose-Derived Stem Cell Population Implicate HOX Genes and WNT Signaling Dysregulation in the Pathogenesis of Thyroid-Associated Orbitopathy.

PubMed

Tao, Wensi; Ayala-Haedo, Juan A; Field, Matthew G; Pelaez, Daniel; Wester, Sara T

2017-12-01

The purpose of this study was to characterize the intrinsic cellular properties of orbital adipose-derived stem cells (OASC) from patients with thyroid-associated orbitopathy (TAO) and healthy controls. Orbital adipose tissue was collected from a total of nine patients: four controls and five patients with TAO. Isolated OASC were characterized with mesenchymal stem cell-specific markers. Orbital adipose-derived stem cells were differentiated into three lineages: chondrocytes, osteocytes, and adipocytes. Reverse transcription PCR of genes involved in the adipogenesis, chondrogenesis, and osteogenesis pathways were selected to assay the differentiation capacities. RNA sequencing analysis (RNA-seq) was performed and results were compared to assess for differences in gene expression between TAO and controls. Selected top-ranked results were confirmed by RT-PCR. Orbital adipose-derived stem cells isolated from orbital fat expressed high levels of mesenchymal stem cell markers, but low levels of the pluripotent stem cell markers. Orbital adipose-derived stem cells isolated from TAO patients exhibited an increase in adipogenesis, and a decrease in chondrogenesis and osteogenesis. RNA-seq disclosed 54 differentially expressed genes. In TAO OASC, expression of early neural crest progenitor marker (WNT signaling, ZIC genes and MSX2) was lost. Meanwhile, ectopic expression of HOXB2 and HOXB3 was found in the OASC from TAO. Our results suggest that there are intrinsic genetic and cellular differences in the OASC populations derived from TAO patients. The upregulation in adipogenesis in OASC of TAO may be is consistent with the clinical phenotype. Downregulation of early neural crest markers and ectopic expression of HOXB2 and HOXB3 in TAO OASC demonstrate dysregulation of developmental and tissue patterning pathways.

Investigation of adhesion and mechanical properties of human glioma cells by single cell force spectroscopy and atomic force microscopy.

PubMed

Andolfi, Laura; Bourkoula, Eugenia; Migliorini, Elisa; Palma, Anita; Pucer, Anja; Skrap, Miran; Scoles, Giacinto; Beltrami, Antonio Paolo; Cesselli, Daniela; Lazzarino, Marco

2014-01-01

Active cell migration and invasion is a peculiar feature of glioma that makes this tumor able to rapidly infiltrate into the surrounding brain tissue. In our recent work, we identified a novel class of glioma-associated-stem cells (defined as GASC for high-grade glioma--HG--and Gasc for low-grade glioma--LG) that, although not tumorigenic, act supporting the biological aggressiveness of glioma-initiating stem cells (defined as GSC for HG and Gsc for LG) favoring also their motility. Migrating cancer cells undergo considerable molecular and cellular changes by remodeling their cytoskeleton and cell interactions with surrounding environment. To get a better understanding about the role of the glioma-associated-stem cells in tumor progression, cell deformability and interactions between glioma-initiating stem cells and glioma-associated-stem cells were investigated. Adhesion of HG/LG-cancer cells on HG/LG-glioma-associated stem cells was studied by time-lapse microscopy, while cell deformability and cell-cell adhesion strengths were quantified by indentation measurements by atomic force microscopy and single cell force spectroscopy. Our results demonstrate that for both HG and LG glioma, cancer-initiating-stem cells are softer than glioma-associated-stem cells, in agreement with their neoplastic features. The adhesion strength of GSC on GASC appears to be significantly lower than that observed for Gsc on Gasc. Whereas, GSC spread and firmly adhere on Gasc with an adhesion strength increased as compared to that obtained on GASC. These findings highlight that the grade of glioma-associated-stem cells plays an important role in modulating cancer cell adhesion, which could affect glioma cell migration, invasion and thus cancer aggressiveness. Moreover this work provides evidence about the importance of investigating cell adhesion and elasticity for new developments in disease diagnostics and therapeutics.

Multipotent adult germ-line stem cells, like other pluripotent stem cells, can be killed by cytotoxic T lymphocytes despite low expression of major histocompatibility complex class I molecules

PubMed Central

Dressel, Ralf; Guan, Kaomei; Nolte, Jessica; Elsner, Leslie; Monecke, Sebastian; Nayernia, Karim; Hasenfuss, Gerd; Engel, Wolfgang

2009-01-01

Background Multipotent adult germ-line stem cells (maGSCs) represent a new pluripotent cell type that can be derived without genetic manipulation from spermatogonial stem cells (SSCs) present in adult testis. Similarly to induced pluripotent stem cells (iPSCs), they could provide a source of cellular grafts for new transplantation therapies of a broad variety of diseases. To test whether these stem cells can be rejected by the recipients, we have analyzed whether maGSCs and iPSCs can become targets for cytotoxic T lymphocytes (CTL) or whether they are protected, as previously proposed for embryonic stem cells (ESCs). Results We have observed that maGSCs can be maintained in prolonged culture with or without leukemia inhibitory factor and/or feeder cells and still retain the capacity to form teratomas in immunodeficient recipients. They were, however, rejected in immunocompetent allogeneic recipients, and the immune response controlled teratoma growth. We analyzed the susceptibility of three maGSC lines to CTL in comparison to ESCs, iPSCs, and F9 teratocarcinoma cells. Major histocompatibility complex (MHC) class I molecules were not detectable by flow cytometry on these stem cell lines, apart from low levels on one maGSC line (maGSC Stra8 SSC5). However, using a quantitative real time PCR analysis H2K and B2m transcripts were detected in all pluripotent stem cell lines. All pluripotent stem cell lines were killed in a peptide-dependent manner by activated CTLs derived from T cell receptor transgenic OT-I mice after pulsing of the targets with the SIINFEKL peptide. Conclusion Pluripotent stem cells, including maGSCs, ESCs, and iPSCs can become targets for CTLs, even if the expression level of MHC class I molecules is below the detection limit of flow cytometry. Thus they are not protected against CTL-mediated cytotoxicity. Therefore, pluripotent cells might be rejected after transplantation by this mechanism if specific antigens are presented and if specific activated CTLs are present. Our results show that the adaptive immune system has in principle the capacity to kill pluripotent and teratoma forming stem cells. This finding might help to develop new strategies to increase the safety of future transplantations of in vitro differentiated cells by exploiting a selective immune response against contaminating undifferentiated cells. Reviewers This article was reviewed by Bhagirath Singh, Etienne Joly and Lutz Walter. PMID:19715575

Differentiation of oligodendrocyte progenitor cells from dissociated monolayer and feeder-free cultured pluripotent stem cells.

PubMed

Yamashita, Tomoko; Miyamoto, Yuki; Bando, Yoshio; Ono, Takashi; Kobayashi, Sakurako; Doi, Ayano; Araki, Toshihiro; Kato, Yosuke; Shirakawa, Takayuki; Suzuki, Yutaka; Yamauchi, Junji; Yoshida, Shigetaka; Sato, Naoya

2017-01-01

Oligodendrocytes myelinate axons and form myelin sheaths in the central nervous system. The development of therapies for demyelinating diseases, including multiple sclerosis and leukodystrophies, is a challenge because the pathogenic mechanisms of disease remain poorly understood. Primate pluripotent stem cell-derived oligodendrocytes are expected to help elucidate the molecular pathogenesis of these diseases. Oligodendrocytes have been successfully differentiated from human pluripotent stem cells. However, it is challenging to prepare large amounts of oligodendrocytes over a short amount of time because of manipulation difficulties under conventional primate pluripotent stem cell culture methods. We developed a proprietary dissociated monolayer and feeder-free culture system to handle pluripotent stem cell cultures. Because the dissociated monolayer and feeder-free culture system improves the quality and growth of primate pluripotent stem cells, these cells could potentially be differentiated into any desired functional cells and consistently cultured in large-scale conditions. In the current study, oligodendrocyte progenitor cells and mature oligodendrocytes were generated within three months from monkey embryonic stem cells. The embryonic stem cell-derived oligodendrocytes exhibited in vitro myelinogenic potency with rat dorsal root ganglion neurons. Additionally, the transplanted oligodendrocyte progenitor cells differentiated into myelin basic protein-positive mature oligodendrocytes in the mouse corpus callosum. This preparative method was used for human induced pluripotent stem cells, which were also successfully differentiated into oligodendrocyte progenitor cells and mature oligodendrocytes that were capable of myelinating rat dorsal root ganglion neurons. Moreover, it was possible to freeze, thaw, and successfully re-culture the differentiating cells. These results showed that embryonic stem cells and human induced pluripotent stem cells maintained in a dissociated monolayer and feeder-free culture system have the potential to generate oligodendrocyte progenitor cells and mature oligodendrocytes in vitro and in vivo. This culture method could be applied to prepare large amounts of oligodendrocyte progenitor cells and mature oligodendrocytes in a relatively short amount of time.

Influence of different types of pulp treatment during isolation in the obtention of human dental pulp stem cells

PubMed Central

Viña-Almunia, Jose; Borras, Consuelo; Gambini, Juan; El Alamy, Marya; Viña, Jose

2016-01-01

Background Different methods have been used in order to isolate dental pulp stem cells. The aim of this study was to study the effect of different types of pulp treatment during isolation, under 3% O2 conditions, in the time needed and the efficacy for obtaining dental pulp stem cells. Material and Methods One hundred and twenty dental pulps were used to isolate dental pulp stem cells treating the pulp tissue during isolation using 9 different methods, using digestive, disgregation, or mechanical agents, or combining them. The cells were positive for CD133, Oct4, Nestin, Stro-1, CD34 markers, and negative for the hematopoietic cell marker CD-45, thus confirming the presence of mesenchymal stem cells. The efficacy of dental pulp stem cells obtention and the minimum time needed to obtain such cells comparing the 9 different methods was analyzed. Results Dental pulp stem cells were obtained from 97 of the 120 pulps used in the study, i.e. 80.8% of the cases. They were obtained with all the methods used except with mechanical fragmentation of the pulp, where no enzymatic digestion was performed. The minimum time needed to isolate dental pulp stem cells was 8 hours, digesting with 2mg/ml EDTA for 10 minutes, 4mg/ml of type I collagenase, 4mg/ml of type II dispase for 40 minutes, 13ng/ml of thermolysine for 40 minutes and sonicating the culture for one minute. Conclusions Dental pulp stem cells were obtained in 97 cases from a series of 120 pulps. The time for obtaining dental pulp stem cells was reduced maximally, without compromising the obtention of the cells, by combining digestive, disgregation, and mechanical agents. Key words:Dental pulp stem cells, mesenchymal stem cells, isolation method. PMID:26946201

Adenoviral overexpression of Lhx2 attenuates cell viability but does not preserve the stem cell like phenotype of hepatic stellate cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Genz, Berit; Thomas, Maria; Pützer, Brigitte M.

2014-11-01

Hepatic stellate cells (HSC) are well known initiators of hepatic fibrosis. After liver cell damage, HSC transdifferentiate into proliferative myofibroblasts, representing the major source of extracellular matrix in the fibrotic organ. Recent studies also demonstrate a role of HSC as progenitor or stem cell like cells in liver regeneration. Lhx2 is described as stem cell maintaining factor in different organs and as an inhibitory transcription factor in HSC activation. Here we examined whether a continuous expression of Lhx2 in HSC could attenuate their activation and whether Lhx2 could serve as a potential target for antifibrotic gene therapy. Therefore, we evaluatedmore » an adenoviral mediated overexpression of Lhx2 in primary HSC and investigated mRNA expression patterns by qRT-PCR as well as the activation status by different in vitro assays. HSC revealed a marked increase in activation markers like smooth muscle actin alpha (αSMA) and collagen 1α independent from adenoviral transduction. Lhx2 overexpression resulted in attenuated cell viability as shown by a slightly hampered migratory and contractile phenotype of HSC. Expression of stem cell factors or signaling components was also unaffected by Lhx2. Summarizing these results, we found no antifibrotic or stem cell maintaining effect of Lhx2 overexpression in primary HSC. - Highlights: • We performed adenoviral overexpression of Lhx2 in primary hepatic stellate cells. • Hepatic stellate cells expressed stem cell markers during cultivation. • Cell migration and contractility was slightly hampered upon Lhx2 overexpression. • Lhx2 overexpression did not affect stem cell character of hepatic stellate cells.« less

Induced stem cell neoplasia in a cnidarian by ectopic expression of a POU domain transcription factor.

PubMed

Millane, R Cathriona; Kanska, Justyna; Duffy, David J; Seoighe, Cathal; Cunningham, Stephen; Plickert, Günter; Frank, Uri

2011-06-01

The evolutionary origin of stem cell pluripotency is an unresolved question. In mammals, pluripotency is limited to early embryos and is induced and maintained by a small number of key transcription factors, of which the POU domain protein Oct4 is considered central. Clonal invertebrates, by contrast, possess pluripotent stem cells throughout their life, but the molecular mechanisms that control their pluripotency are poorly defined. To address this problem, we analyzed the expression pattern and function of Polynem (Pln), a POU domain gene from the marine cnidarian Hydractinia echinata. We show that Pln is expressed in the embryo and adult stem cells of the animal and that ectopic expression in epithelial cells induces stem cell neoplasms and loss of epithelial tissue. Neoplasm cells downregulated the transgene but expressed the endogenous Pln gene and also Nanos, Vasa, Piwi and Myc, which are all known cnidarian stem cell markers. Retinoic acid treatment caused downregulation of Pln and the differentiation of neoplasm cells to neurosensory and epithelial cells. Pln downregulation by RNAi led to differentiation. Collectively, our results suggest an ancient role of POU proteins as key regulators of animal stem cells.

Single-cell telomere-length quantification couples telomere length to meristem activity and stem cell development in Arabidopsis.

PubMed

González-García, Mary-Paz; Pavelescu, Irina; Canela, Andrés; Sevillano, Xavier; Leehy, Katherine A; Nelson, Andrew D L; Ibañes, Marta; Shippen, Dorothy E; Blasco, Maria A; Caño-Delgado, Ana I

2015-05-12

Telomeres are specialized nucleoprotein caps that protect chromosome ends assuring cell division. Single-cell telomere quantification in animals established a critical role for telomerase in stem cells, yet, in plants, telomere-length quantification has been reported only at the organ level. Here, a quantitative analysis of telomere length of single cells in Arabidopsis root apex uncovered a heterogeneous telomere-length distribution of different cell lineages showing the longest telomeres at the stem cells. The defects in meristem and stem cell renewal observed in tert mutants demonstrate that telomere lengthening by TERT sets a replicative limit in the root meristem. Conversely, the long telomeres of the columella cells and the premature stem cell differentiation plt1,2 mutants suggest that differentiation can prevent telomere erosion. Overall, our results indicate that telomere dynamics are coupled to meristem activity and continuous growth, disclosing a critical association between telomere length, stem cell function, and the extended lifespan of plants. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

The Extracellular Environment's Effect on Cellular Processes: An In Vitro Study of Mechanical and Chemical Cues on Human Mesenchymal Stem Cells and C17.2 Neural Stem Cells

NASA Astrophysics Data System (ADS)

Casey, Meghan E.

Stem cells are widely used in the area of tissue engineering. The ability of cells to interact with materials on the nano- and micro- level is important in the success of the biomaterial. It is well-known that cells respond to their micro- and nano-environments through a process termed chemo-mechanotransduction. It is important to establish standard protocols for cellular experiments, as chemical modifications to maintenance environments can alter long-term research results. In this work, the effects of different media compositions on human mesenchymal stem cells (hMSCs) throughout normal in vitro maintenance are investigated. Changes in RNA regulation, protein expression and proliferation are studied via quantitative polymerase chain reaction (qPCR), immunocytochemistry (ICC) and cell counts, respectively. Morphological differences are also observed throughout the experiment. Results of this study illustrate the dynamic response of hMSC maintenance to differences in growth medium and passage number. These experiments highlight the effect growth medium has on in vitro experiments and the need of consistent protocols in hMSC research. A substantial opportunity exists in neuronal research to develop a material platform that allows for both the proliferation and differentiation of stem cells into neurons and the ability to quantify the secretome of neuronal cells. Anodic aluminum oxide (AAO) membranes are fabricated in a two-step anodization procedure where voltage is varied to control the pore size and morphology of the membranes. C17.2 neural stem cells are differentiated on the membranes via serum-withdrawal. Cellular growth is characterized by scanning electron microscopy (SEM), ICC and qPCR. ImageJ software is used to obtain phenotypic cell counts and neurite outgrowth lengths. Results indicate a highly tunable correlation between AAO nanopore sizes and differentiated cell populations. By selecting AAO membranes with specific pore size ranges, control of neuronal network density and neurite outgrowth length is achievable. To understand differentiation marker expressions in C17.2 NSCs and how material stiffness affects differentiation, cells are cultured on substrates of varying stiffness. qPCR is used to analyze neural stem cell, neural progenitor cell, neuron-restricted progenitor and differentiated post-mitotic neuronal cell RNA expression. Results suggest a relationship between material stiffness and neuronal development in C17.2 neural stem cells.

Adult Palatum as a Novel Source of Neural Crest-Related Stem Cells

PubMed Central

Widera, Darius; Zander, Christin; Heidbreder, Meike; Kasperek, Yvonne; Noll, Thomas; Seitz, Oliver; Saldamli, Belma; Sudhoff, Holger; Sader, Robert; Kaltschmidt, Christian; Kaltschmidt, Barbara

2009-01-01

Somatic neural and neural crest stem cells are promising sources for cellular therapy of several neurodegenerative diseases. However, because of practical considerations such as inadequate accessibility of the source material, the application of neural crest stem cells is strictly limited. The secondary palate is a highly regenerative and heavily innervated tissue, which develops embryonically under direct contribution of neural crest cells. Here, we describe for the first time the presence of nestin-positive neural crest-related stem cells within Meissner corpuscles and Merkel cell-neurite complexes located in the hard palate of adult Wistar rats. After isolation, palatal neural crest-related stem cells (pNC-SCs) were cultivated in the presence of epidermal growth factor and fibroblast growth factor under serum-free conditions, resulting in large amounts of neurospheres. We used immunocytochemical techniques and reverse transcriptase-polymerase chain reaction to assess the expression profile of pNC-SCs. In addition to the expression of neural crest stem cell markers such as Nestin, Sox2, and p75, we detected the expression of Klf4, Oct4, and c-Myc. pNC-SCs differentiated efficiently into neuronal and glial cells. Finally, we investigated the potential expression of stemness markers within the human palate. We identified expression of stem cell markers nestin and CD133 and the transcription factors needed for reprogramming of somatic cells into pluripotent cells: Sox2, Oct4, Klf4, and c-Myc. These data show that cells isolated from palatal rugae form neurospheres, are highly plastic, and express neural crest stem cell markers. In addition, pNC-SCs may have the ability to differentiate into functional neurons and glial cells, serving as a starting point for therapeutic studies. Stem Cells 2009;27:1899–1910 PMID:19544446

Interplay of migratory and division forces as a generic mechanism for stem cell patterns

NASA Astrophysics Data System (ADS)

Hannezo, Edouard; Coucke, Alice; Joanny, Jean-François

2016-02-01

In many adult tissues, stem cells and differentiated cells are not homogeneously distributed: stem cells are arranged in periodic "niches," and differentiated cells are constantly produced and migrate out of these niches. In this article, we provide a general theoretical framework to study mixtures of dividing and actively migrating particles, which we apply to biological tissues. We show in particular that the interplay between the stresses arising from active cell migration and stem cell division give rise to robust stem cell patterns. The instability of the tissue leads to spatial patterns which are either steady or oscillating in time. The wavelength of the instability has an order of magnitude consistent with the biological observations. We also discuss the implications of these results for future in vitro and in vivo experiments.

Slow-cycling stem cells in hydra contribute to head regeneration

PubMed Central

Govindasamy, Niraimathi; Murthy, Supriya; Ghanekar, Yashoda

2014-01-01

ABSTRACT Adult stem cells face the challenge of maintaining tissue homeostasis by self-renewal while maintaining their proliferation potential over the lifetime of an organism. Continuous proliferation can cause genotoxic/metabolic stress that can compromise the genomic integrity of stem cells. To prevent stem cell exhaustion, highly proliferative adult tissues maintain a pool of quiescent stem cells that divide only in response to injury and thus remain protected from genotoxic stress. Hydra is a remarkable organism with highly proliferative stem cells and ability to regenerate at whole animal level. Intriguingly, hydra does not display consequences of high proliferation, such as senescence or tumour formation. In this study, we investigate if hydra harbours a pool of slow-cycling stem cells that could help prevent undesirable consequences of continuous proliferation. Hydra were pulsed with the thymidine analogue 5-ethynyl-2′-deoxyuridine (EdU) and then chased in the absence of EdU to monitor the presence of EdU-retaining cells. A significant number of undifferentiated cells of all three lineages in hydra retained EdU for about 8–10 cell cycles, indicating that these cells did not enter cell cycle. These label-retaining cells were resistant to hydroxyurea treatment and were predominantly in the G2 phase of cell cycle. Most significantly, similar to mammalian quiescent stem cells, these cells rapidly entered cell division during head regeneration. This study shows for the first time that, contrary to current beliefs, cells in hydra display heterogeneity in their cell cycle potential and the slow-cycling cells in this population enter cell cycle during head regeneration. These results suggest an early evolution of slow-cycling stem cells in multicellular animals. PMID:25432513

Erosion of the chronic myeloid leukaemia stem cell pool by PPARγ agonists.

PubMed

Prost, Stéphane; Relouzat, Francis; Spentchian, Marc; Ouzegdouh, Yasmine; Saliba, Joseph; Massonnet, Gérald; Beressi, Jean-Paul; Verhoeyen, Els; Raggueneau, Victoria; Maneglier, Benjamin; Castaigne, Sylvie; Chomienne, Christine; Chrétien, Stany; Rousselot, Philippe; Leboulch, Philippe

2015-09-17

Whether cancer is maintained by a small number of stem cells or is composed of proliferating cells with approximate phenotypic equivalency is a central question in cancer biology. In the stem cell hypothesis, relapse after treatment may occur by failure to eradicate cancer stem cells. Chronic myeloid leukaemia (CML) is quintessential to this hypothesis. CML is a myeloproliferative disorder that results from dysregulated tyrosine kinase activity of the fusion oncoprotein BCR-ABL. During the chronic phase, this sole genetic abnormality (chromosomal translocation Ph(+): t(9;22)(q34;q11)) at the stem cell level causes increased proliferation of myeloid cells without loss of their capacity to differentiate. Without treatment, most patients progress to the blast phase when additional oncogenic mutations result in a fatal acute leukaemia made of proliferating immature cells. Imatinib mesylate and other tyrosine kinase inhibitors (TKIs) that target the kinase activity of BCR-ABL have improved patient survival markedly. However, fewer than 10% of patients reach the stage of complete molecular response (CMR), defined as the point when BCR-ABL transcripts become undetectable in blood cells. Failure to reach CMR results from the inability of TKIs to eradicate quiescent CML leukaemia stem cells (LSCs). Here we show that the residual CML LSC pool can be gradually purged by the glitazones, antidiabetic drugs that are agonists of peroxisome proliferator-activated receptor-γ (PPARγ). We found that activation of PPARγ by the glitazones decreases expression of STAT5 and its downstream targets HIF2α and CITED2, which are key guardians of the quiescence and stemness of CML LSCs. When pioglitazone was given temporarily to three CML patients in chronic residual disease in spite of continuous treatment with imatinib, all of them achieved sustained CMR, up to 4.7 years after withdrawal of pioglitazone. This suggests that clinically relevant cancer eradication may become a generally attainable goal by combination therapy that erodes the cancer stem cell pool.

Smed-SmB, a member of the LSm protein superfamily, is essential for chromatoid body organization and planarian stem cell proliferation.

PubMed

Fernandéz-Taboada, Enrique; Moritz, Sören; Zeuschner, Dagmar; Stehling, Martin; Schöler, Hans R; Saló, Emili; Gentile, Luca

2010-04-01

Planarians are an ideal model system to study in vivo the dynamics of adult pluripotent stem cells. However, our knowledge of the factors necessary for regulating the 'stemness' of the neoblasts, the adult stem cells of planarians, is sparse. Here, we report on the characterization of the first planarian member of the LSm protein superfamily, Smed-SmB, which is expressed in stem cells and neurons in Schmidtea mediterranea. LSm proteins are highly conserved key players of the splicing machinery. Our study shows that Smed-SmB protein, which is localized in the nucleus and the chromatoid body of stem cells, is required to safeguard the proliferative ability of the neoblasts. The chromatoid body, a cytoplasmatic ribonucleoprotein complex, is an essential regulator of the RNA metabolism required for the maintenance of metazoan germ cells. However, planarian neoblasts and neurons also rely on its functions. Remarkably, Smed-SmB dsRNA-mediated knockdown results in a rapid loss of organization of the chromatoid body, an impairment of the ability to post-transcriptionally process the transcripts of Smed-CycB, and a severe proliferative failure of the neoblasts. This chain of events leads to a quick depletion of the neoblast pool, resulting in a lethal phenotype for both regenerating and intact animals. In summary, our results suggest that Smed-SmB is an essential component of the chromatoid body, crucial to ensure a proper RNA metabolism and essential for stem cell proliferation.

Prion diseases and adult neurogenesis: how do prions counteract the brain's endogenous repair machinery?

PubMed

Relaño-Ginés, Aroa; Lehmann, Sylvain; Crozet, Carole

2014-01-01

Scientific advances in stem cell biology and adult neurogenesis have raised the hope that neurodegenerative disorders could benefit from stem cell-based therapy. Adult neurogenesis might be part of the physiological regenerative process, however it might become impaired by the disease's mechanism and therefore contribute to neurodegeneration. In prion disorders this endogenous repair system has rarely been studied. Whether adult neurogenesis plays a role or not in brain repair or in the propagation of prion pathology remains unclear. We have recently investigated the status of adult neural stem cells isolated from prion-infected mice. We were able to show that neural stem cells accumulate and replicate prions thus resulting in an alteration of their neuronal destiny. We also reproduced these results in adult neural stem cells, which were infected in vitro. The fact that endogenous adult neurogenesis could be altered by the accumulation of misfolded prion protein represents another great challenge. Inhibiting prion propagation in these cells would thus help the endogenous neurogenesis to compensate for the injured neuronal system. Moreover, understanding the endogenous modulation of the neurogenesis system would help develop effective neural stem cell-based therapies.

Advances of Stem Cell Therapeutics in Cutaneous Wound Healing and Regeneration

PubMed Central

Kanji, Suman

2017-01-01

Cutaneous wound healing is a complex multiple phase process, which overlaps each other, where several growth factors, cytokines, chemokines, and various cells interact in a well-orchestrated manner. However, an imbalance in any of these phases and factors may lead to disruption in harmony of normal wound healing process, resulting in transformation towards chronic nonhealing wounds and abnormal scar formation. Although various therapeutic interventions are available to treat chronic wounds, current wound-care has met with limited success. Progenitor stem cells possess potential therapeutic ability to overcome limitations of the present treatments as it offers accelerated wound repair with tissue regeneration. A substantial number of stem cell therapies for cutaneous wounds are currently under development as a result of encouraging preliminary findings in both preclinical and clinical studies. However, the mechanisms by which these stem cells contribute to the healing process have yet to be elucidated. In this review, we emphasize on the major treatment modalities currently available for the treatment of the wound, role of various interstitial stem cells and exogenous adult stem cells in cutaneous wound healing, and possible mechanisms involved in the healing process. PMID:29213192

Balanced cell proliferation and expansion is essential for flowering stem growth control.

PubMed

Ferjani, Ali; Hanai, Kenya; Gunji, Shizuka; Maeda, Saori; Sawa, Shinichiro; Tsukaya, Hirokazu

2015-01-01

The postembryonic development of aboveground plant organs relies on a continuous supply of cells from the shoot apical meristem. Previous studies of developmental regulation in leaves and flowers have revealed the crucial role of coordinated cell proliferation and differentiation during organogenesis. However, the importance of this coordination has not been examined in flowering stems. Very recently, we attempted to identify regulatory factors that maintain flowering stem integrity. We found that the increased cell number in clavata (clv) mutants and the decreased cell size in de-etiolated (det)3-1 resulted in flowering stems that were thicker and thinner, respectively, than in wild-type (WT) plants. Interestingly, in the cell proliferation- and cell expansion-defective double mutant clv det3-1, the flowering stems often exhibited severe cracking, resulting in exposure of their inner tissues. In this study, further quantification of the cellular phenotypes in the cotyledons and leaves revealed no differences between det3-1 and clv3 det3-1. Together, the above findings suggest that the clv3 mutation in a det3-1 background primarily affects flowering stems, while its effect on other organs is likely negligible. We propose that the coordination between cell proliferation and differentiation is not only important during leaf development, but also plays a role in the growth control of Arabidopsis flowering stems.

SCF increases in utero-labeled stem cells migration and improves wound healing.

PubMed

Zgheib, Carlos; Xu, Junwang; Mallette, Andrew C; Caskey, Robert C; Zhang, Liping; Hu, Junyi; Liechty, Kenneth W

2015-01-01

Diabetic skin wounds lack the ability to heal properly and constitute a major and significant complication of diabetes. Nontraumatic lower extremity amputations are the number one complication of diabetic skin wounds. The complexity of their pathophysiology requires an intervention at many levels to enhance healing and wound closure. Stem cells are a promising treatment for diabetic skin wounds as they have the ability to correct abnormal healing. Stem cell factor (SCF), a chemokine expressed in the skin, can induce stem cells migration, however the role of SCF in diabetic skin wound healing is still unknown. We hypothesize that SCF would correct the impairment and promote the healing of diabetic skin wounds. Our results show that SCF improved wound closure in diabetic mice and increased HIF-1α and vascular endothelial growth factor (VEGF) expression levels in these wounds. SCF treatment also enhanced the migration of red fluorescent protein (RFP)-labeled skin stem cells via in utero intra-amniotic injection of lenti-RFP at E8. Interestingly these RFP+ cells are present in the epidermis, stain negative for K15, and appear to be distinct from the already known hair follicle stem cells. These results demonstrate that SCF improves diabetic wound healing in part by increasing the recruitment of a unique stem cell population present in the skin. © 2015 by the Wound Healing Society.

Directing Stem Cell Differentiation via Electrochemical Reversible Switching between Nanotubes and Nanotips of Polypyrrole Array.

PubMed

Wei, Yan; Mo, Xiaoju; Zhang, Pengchao; Li, Yingying; Liao, Jingwen; Li, Yongjun; Zhang, Jinxing; Ning, Chengyun; Wang, Shutao; Deng, Xuliang; Jiang, Lei

2017-06-27

Control of stem cell behaviors at solid biointerfaces is critical for stem-cell-based regeneration and generally achieved by engineering chemical composition, topography, and stiffness. However, the influence of dynamic stimuli at the nanoscale from solid biointerfaces on stem cell fate remains unclear. Herein, we show that electrochemical switching of a polypyrrole (Ppy) array between nanotubes and nanotips can alter surface adhesion, which can strongly influence mechanotransduction activation and guide differentiation of mesenchymal stem cells (MSCs). The Ppy array, prepared via template-free electrochemical polymerization, can be reversibly switched between highly adhesive hydrophobic nanotubes and poorly adhesive hydrophilic nanotips through an electrochemical oxidation/reduction process, resulting in dynamic attachment and detachment to MSCs at the nanoscale. Multicyclic attachment/detachment of the Ppy array to MSCs can activate intracellular mechanotransduction and osteogenic differentiation independent of surface stiffness and chemical induction. This smart surface, permitting transduction of nanoscaled dynamic physical inputs into biological outputs, provides an alternative to classical cell culture substrates for regulating stem cell fate commitment. This study represents a general strategy to explore nanoscaled interactions between stem cells and stimuli-responsive surfaces.

Is There Any Reason to Prefer Cord Blood Instead of Adult Donors for Hematopoietic Stem Cell Transplants?

PubMed

Beksac, Meral

2015-01-01

As cord blood (CB) enables rapid access and tolerance to HLA mismatches, a number of unrelated CB transplants have reached 30,000. Such transplant activity has been the result of international accreditation programs maintaining highly qualified cord blood units (CBUs) reaching more than 600,000 CBUs stored worldwide. Efforts to increase stem cell content or engraftment rate of the graft by ex vivo expansion, modulation by molecules such as fucose, prostaglandin E2 derivative, complement CD26 inhibitors, or CXCR4/CXCL12 axis have been able to accelerate engraftment speed and rate. Furthermore, introduction of reduced intensity conditioning protocols, better HLA matching, and recognition of the importance of HLA-C have improved CB transplants success by decreasing transplant-related mortality. CB progenitor/stem cell content has been compared with adult stem cells revealing higher long-term repopulating capacity compared to bone marrow-mesenchymal stromal cells and lesser oncogenic potential than progenitor-induced stem cells. This chapter summarizes the advantages and disadvantages of CB compared to adult stem cells within the context of stem cell biology and transplantation.

Integrating human stem cell expansion and neuronal differentiation in bioreactors

PubMed Central

Serra, Margarida; Brito, Catarina; Costa, Eunice M; Sousa, Marcos FQ; Alves, Paula M

2009-01-01

Background Human stem cells are cellular resources with outstanding potential for cell therapy. However, for the fulfillment of this application, major challenges remain to be met. Of paramount importance is the development of robust systems for in vitro stem cell expansion and differentiation. In this work, we successfully developed an efficient scalable bioprocess for the fast production of human neurons. Results The expansion of undifferentiated human embryonal carcinoma stem cells (NTera2/cl.D1 cell line) as 3D-aggregates was firstly optimized in spinner vessel. The media exchange operation mode with an inoculum concentration of 4 × 105 cell/mL was the most efficient strategy tested, with a 4.6-fold increase in cell concentration achieved in 5 days. These results were validated in a bioreactor where similar profile and metabolic performance were obtained. Furthermore, characterization of the expanded population by immunofluorescence microscopy and flow cytometry showed that NT2 cells maintained their stem cell characteristics along the bioreactor culture time. Finally, the neuronal differentiation step was integrated in the bioreactor process, by addition of retinoic acid when cells were in the middle of the exponential phase. Neurosphere composition was monitored and neuronal differentiation efficiency evaluated along the culture time. The results show that, for bioreactor cultures, we were able to increase significantly the neuronal differentiation efficiency by 10-fold while reducing drastically, by 30%, the time required for the differentiation process. Conclusion The culture systems developed herein are robust and represent one-step-forward towards the development of integrated bioprocesses, bridging stem cell expansion and differentiation in fully controlled bioreactors. PMID:19772662

Designing the stem cell microenvironment for guided connective tissue regeneration.

PubMed

Bogdanowicz, Danielle R; Lu, Helen H

2017-12-01

Adult mesenchymal stem cells (MSCs) are an attractive cell source for regenerative medicine because of their ability to self-renew and their capacity for multilineage differentiation and tissue regeneration. For connective tissues, such as ligaments or tendons, MSCs are vital to the modulation of the inflammatory response following acute injury while also interacting with resident fibroblasts to promote cell proliferation and matrix synthesis. To date, MSC injection for connective tissue repair has yielded mixed results in vivo, likely due to a lack of appropriate environmental cues to effectively control MSC response and promote tissue healing instead of scar formation. In healthy tissues, stem cells reside within a complex microenvironment comprising cellular, structural, and signaling cues that collectively maintain stemness and modulate tissue homeostasis. Changes to the microenvironment following injury regulate stem cell differentiation, trophic signaling, and tissue healing. Here, we focus on models of the stem cell microenvironment that are used to elucidate the mechanisms of stem cell regulation and inspire functional approaches to tissue regeneration. Recent studies in this frontier area are highlighted, focusing on how microenvironmental cues modulate MSC response following connective tissue injury and, more importantly, how this unique cell environment can be programmed for stem cell-guided tissue regeneration. © 2017 New York Academy of Sciences.

Fundamental Principles of Stem Cell Banking.

PubMed

Sun, Changbin; Yue, Jianhui; He, Na; Liu, Yaqiong; Zhang, Xi; Zhang, Yong

2016-01-01

Stem cells are highly promising resources for application in cell therapy, regenerative medicine, drug discovery, toxicology and developmental biology research. Stem cell banks have been increasingly established all over the world in order to preserve their cellular characteristics, prevent contamination and deterioration, and facilitate their effective use in basic and translational research, as well as current and future clinical application. Standardization and quality control during banking procedures are essential to allow researchers from different labs to compare their results and to develop safe and effective new therapies. Furthermore, many stem cells come from once-in-a-life time tissues. Cord blood for example, thrown away in the past, can be used to treat many diseases such as blood cancers nowadays. Meanwhile, these cells stored and often banked for long periods can be immediately available for treatment when needed and early treatment can minimize disease progression. This paper provides an overview of the fundamental principles of stem cell banking, including: (i) a general introduction of the construction and architecture commonly used for stem cell banks; (ii) a detailed section on current quality management practices; (iii) a summary of questions we should consider for long-term storage, such as how long stem cells can be stored stably, how to prevent contamination during long term storage, etc.; (iv) the prospects for stem cell banking.

Direct Reprogramming of Human Amniotic Fluid Stem Cells by OCT4 and Application in Repairing of Cerebral Ischemia Damage

PubMed Central

Qin, Mingde; Chen, Ruihua; Li, Hong; Liang, Hansi; Xue, Qun; Li, Fang; Chen, Ying; Zhang, Xueguang

2016-01-01

Amniotic fluid stem cells (AFSCs) are a type of fetal stem cell whose stemness encompasses both embryonic and adult stem cells, suggesting that they may be easily and efficiently reprogrammed into induced pluripotent stem cells (iPSCs). To further simplify the reprogramming process, the creation of AFSC-derived iPSCs using a single factor is desirable. Here we report the generation of one-factor human AFSC-iPSCs (AiPSCs) from human AFSCs by ectopic expression of the transcription factor OCT4. Just like human embryonic stem cells, AiPSCs exhibited similar epigenetic status, global gene expression profiles, teratoma formation and in vitro & in vivo pluripotency. Our results indicate that the OCT4 is necessary and sufficient to directly reprogram human AFSCs into pluripotent AiPSCs. Moreover, reflecting the similar memory characteristics of AFSCs and neural stem cells, we show that AiPSC membrane-derived vesicles (MVs) repair cerebral ischemia damage. We anticipate that the successful generation of one-factor AiPSCs will facilitate the creation of patient-specific pluripotent stem cells without the need for transgenic expression of oncogenes. Moreover, MVs from tissue-specific AiPSCs have potential in tissue repair, representing a novel application of iPSCs. PMID:27019637

Stem cell signaling as a target for novel drug discovery: recent progress in the WNT and Hedgehog pathways.

PubMed

An, Songzhu Michael; Ding, Qiang Peter; Li, Ling-song

2013-06-01

One of the most exciting fields in biomedical research over the past few years is stem cell biology, and therapeutic application of stem cells to replace the diseased or damaged tissues is also an active area in development. Although stem cell therapy has a number of technical challenges and regulatory hurdles to overcome, the use of stem cells as tools in drug discovery supported by mature technologies and established regulatory paths is expected to generate more immediate returns. In particular, the targeting of stem cell signaling pathways is opening up a new avenue for drug discovery. Aberrations in these pathways result in various diseases, including cancer, fibrosis and degenerative diseases. A number of drug targets in stem cell signaling pathways have been identified. Among them, WNT and Hedgehog are two most important signaling pathways, which are the focus of this review. A hedgehog pathway inhibitor, vismodegib (Erivedge), has recently been approved by the US FDA for the treatment of skin cancer, while several drug candidates for the WNT pathway are entering clinical trials. We have discovered that the stem cell signaling pathways respond to traditional Chinese medicines. Substances isolated from herbal medicine may act specifically on components of stem cell signaling pathways with high affinities. As many of these events can be explained through molecular interactions, these phenomena suggest that discovery of stem cell-targeting drugs from natural products may prove to be highly successful.

Notch1 stimulation induces a vascularization switch with pericyte-like cell differentiation of glioblastoma stem cells.

PubMed

Guichet, Pierre-Olivier; Guelfi, Sophie; Teigell, Marisa; Hoppe, Liesa; Bakalara, Norbert; Bauchet, Luc; Duffau, Hugues; Lamszus, Katrin; Rothhut, Bernard; Hugnot, Jean-Philippe

2015-01-01

Glioblastoma multiforms (GBMs) are highly vascularized brain tumors containing a subpopulation of multipotent cancer stem cells. These cells closely interact with endothelial cells in neurovascular niches. In this study, we have uncovered a close link between the Notch1 pathway and the tumoral vascularization process of GBM stem cells. We observed that although the Notch1 receptor was activated, the typical target proteins (HES5, HEY1, and HEY2) were not or barely expressed in two explored GBM stem cell cultures. Notch1 signaling activation by expression of the intracellular form (NICD) in these cells was found to reduce their growth rate and migration, which was accompanied by the sharp reduction in neural stem cell transcription factor expression (ASCL1, OLIG2, and SOX2), while HEY1/2, KLF9, and SNAI2 transcription factors were upregulated. Expression of OLIG2 and growth were restored after termination of Notch1 stimulation. Remarkably, NICD expression induced the expression of pericyte cell markers (NG2, PDGFRβ, and α-smooth muscle actin [αSMA]) in GBM stem cells. This was paralleled with the induction of several angiogenesis-related factors most notably cytokines (heparin binding epidermal growth factor [HB-EGF], IL8, and PLGF), matrix metalloproteinases (MMP9), and adhesion proteins (vascular cell adhesion molecule 1 [VCAM1], intercellular adhesion molecule 1 [ICAM1], and integrin alpha 9 [ITGA9]). In xenotransplantation experiments, contrasting with the infiltrative and poorly vascularized tumors obtained with control GBM stem cells, Notch1 stimulation resulted in poorly disseminating but highly vascularized grafts containing large vessels with lumen. Notch1-stimulated GBM cells expressed pericyte cell markers and closely associated with endothelial cells. These results reveal an important role for the Notch1 pathway in regulating GBM stem cell plasticity and angiogenic properties. © 2014 AlphaMed Press.

A block in lineage differentiation of immortal human mammary stem / progenitor cells by ectopically-expressed oncogenes

PubMed Central

Zhao, Xiangshan; Malhotra, Gautam K.; Band, Hamid; Band, Vimla

2011-01-01

Introduction: Emerging evidence suggests a direct role of cancer stem cells (CSCs) in the development of breast cancer. In vitro cellular models that recapitulate properties of CSCs are therefore highly desirable. We have previously shown that normal human mammary epithelial cells (hMECs) immortalized with human telomerase reverse transcriptase (hTERT) possess properties of mammary stem / progenitor cells. Materials and Methods: In the present study, we used this cell system to test the idea that other known hMEC-immortalizing oncogenes (RhoA, HPVE6, HPVE7, p53 mutant, and treatment with γ-radiation), share with hTERT, the ability to maintain mammary stem / progenitor cells. Results: The results presented here demonstrate that similar to hMECs immortalized with hTERT, all hMEC cell lines immortalized using various oncogenic strategies express stem / progenitor cell markers. Furthermore, analyses using 2D and 3D culture assays demonstrate that all the immortal cell lines retain their ability to self-renew and to differentiate along the luminal lineage. Remarkably, the stem / progenitor cell lines generated using various oncogenic strategies exhibit a block in differentiation along the myoepithelial lineage, a trait that is retained on hTERT-immortalized stem / progenitors. The inability to differentiate along the myoepithelial lineage could be induced by ectopic mutant p53 expression in hTERT-immortalized hMEC. Conclusions: Our studies demonstrate that stem / progenitor cell characteristics of hMECs are maintained upon immortalization by using various cancer-relevant oncogenic strategies. Oncogene-immortalized hMECs show a block in their ability to differentiate along the myoepithelial lineage. Abrogation of the myoepithelial differentiation potential by a number of distinct oncogenic insults suggests a potential explanation for the predominance of luminal and rarity of myoepithelial breast cancers. PMID:22279424

Symmetric vs. Asymmetric Stem Cell Divisions: An Adaptation against Cancer?

PubMed Central

Shahriyari, Leili; Komarova, Natalia L.

2013-01-01

Traditionally, it has been held that a central characteristic of stem cells is their ability to divide asymmetrically. Recent advances in inducible genetic labeling provided ample evidence that symmetric stem cell divisions play an important role in adult mammalian homeostasis. It is well understood that the two types of cell divisions differ in terms of the stem cells' flexibility to expand when needed. On the contrary, the implications of symmetric and asymmetric divisions for mutation accumulation are still poorly understood. In this paper we study a stochastic model of a renewing tissue, and address the optimization problem of tissue architecture in the context of mutant production. Specifically, we study the process of tumor suppressor gene inactivation which usually takes place as a consequence of two “hits”, and which is one of the most common patterns in carcinogenesis. We compare and contrast symmetric and asymmetric (and mixed) stem cell divisions, and focus on the rate at which double-hit mutants are generated. It turns out that symmetrically-dividing cells generate such mutants at a rate which is significantly lower than that of asymmetrically-dividing cells. This result holds whether single-hit (intermediate) mutants are disadvantageous, neutral, or advantageous. It is also independent on whether the carcinogenic double-hit mutants are produced only among the stem cells or also among more specialized cells. We argue that symmetric stem cell divisions in mammals could be an adaptation which helps delay the onset of cancers. We further investigate the question of the optimal fraction of stem cells in the tissue, and quantify the contribution of non-stem cells in mutant production. Our work provides a hypothesis to explain the observation that in mammalian cells, symmetric patterns of stem cell division seem to be very common. PMID:24204602

Autophagy in stem cells

PubMed Central

Guan, Jun-Lin; Simon, Anna Katharina; Prescott, Mark; Menendez, Javier A.; Liu, Fei; Wang, Fen; Wang, Chenran; Wolvetang, Ernst; Vazquez-Martin, Alejandro; Zhang, Jue

2013-01-01

Autophagy is a highly conserved cellular process by which cytoplasmic components are sequestered in autophagosomes and delivered to lysosomes for degradation. As a major intracellular degradation and recycling pathway, autophagy is crucial for maintaining cellular homeostasis as well as remodeling during normal development, and dysfunctions in autophagy have been associated with a variety of pathologies including cancer, inflammatory bowel disease and neurodegenerative disease. Stem cells are unique in their ability to self-renew and differentiate into various cells in the body, which are important in development, tissue renewal and a range of disease processes. Therefore, it is predicted that autophagy would be crucial for the quality control mechanisms and maintenance of cellular homeostasis in various stem cells given their relatively long life in the organisms. In contrast to the extensive body of knowledge available for somatic cells, the role of autophagy in the maintenance and function of stem cells is only beginning to be revealed as a result of recent studies. Here we provide a comprehensive review of the current understanding of the mechanisms and regulation of autophagy in embryonic stem cells, several tissue stem cells (particularly hematopoietic stem cells), as well as a number of cancer stem cells. We discuss how recent studies of different knockout mice models have defined the roles of various autophagy genes and related pathways in the regulation of the maintenance, expansion and differentiation of various stem cells. We also highlight the many unanswered questions that will help to drive further research at the intersection of autophagy and stem cell biology in the near future. PMID:23486312

Tracking the rise of stem cell tourism.

PubMed

Ryan, Kirsten A; Sanders, Amanda N; Wang, Dong D; Levine, Aaron D

2010-01-01

Driven by hype surrounding stem cell research, a number of clinics around the world currently offer 'stem cell therapies' to patients. These unproven interventions have attracted policy interest owing to the risks they may pose to patients and to the progress of legitimate translational stem cell research, yet remarkably little data exists about the patients who undergo these unproven therapies or their experiences. We sought to characterize this patient population. We developed a comprehensive data set of blogs written by patients (or their caretakers) about their experiences with unproven stem cell therapies. Analyzing these data suggests that unproven stem cell therapies are increasing rapidly in popularity and are attracting a wide range of patients--both young and old and with a diverse collection of medical conditions. These results should help clinicians advise individual patients and help policymakers devise strategies to mitigate the risks these treatments pose.

Reassessing direct-to-consumer portrayals of unproven stem cell therapies: is it getting better?

PubMed

Ogbogu, Ubaka; Rachul, Christen; Caulfield, Timothy

2013-05-01

To determine whether increased scrutiny of 'stem cell tourism' has resulted in changes to online claims by clinics that provide putative unproven stem cell treatments. We analyzed historical and current versions of clinics' websites. The study sample consisted of 18 websites included in a 2008 peer-reviewed study and an additional 12 clinics identified through the Google™ search engine. Our analysis revealed similarities between historical and current stem cell treatment offerings, claims, representations of risk, benefit and efficacy and attention to social, ethical and regulatory concerns. Claims and representations remain overly optimistic. Current websites provide more detailed descriptions of treatment procedures and outcomes and are more aesthetically appealing. Noteworthy trends in the movements and locations of clinics was observed. Increased scrutiny of stem cell tourism has not had much impact on the online claims of clinics that provide putative unproven stem cell treatments.

In Vivo Imaging and Monitoring of Transplanted Stem Cells: Clinical Applications

PubMed Central

Rodriguez-Porcel, Martin

2010-01-01

Regenerative medicine using stem cells has appeared as a potential therapeutic alternative for coronary artery disease, and stem cell clinical studies are currently on their way. However, initial results of these studies have provided mixed information, in part because of the inability to correlate organ functional information with the presence/absence of transplanted stem cells. Recent advances in molecular biology and imaging have allowed the successful noninvasive monitoring of transplanted stem cells in the living subject. In this article, different imaging strategies (direct labeling, indirect labeling with reporter genes) to study the viability and biology of stem cells are discussed. In addition, the limitations of each approach and imaging modality (eg, single photon emission computed tomography, positron emission tomography, and MRI) and their requirements for clinical use are addressed. Use of these strategies will be critical as the different regenerative therapies are being tested for clinical use. PMID:20425184

The Effect of In Vivo Mobilization of Bone Marrow Stem Cells on the Pancreas of Diabetic Albino Rats (A Histological & Immunohistochemical Study)

PubMed Central

Ismail, Zeinab Mohamed Kamel; Kamel, Ashraf Mahmoud Fawzy; Yacoub, Mira Farouk Youssef; Aboulkhair, Alshaymaa Gamal

2013-01-01

Background and Objectives The rapidly increasing number of diabetic patients across the world drew the attention to develop more effective therapeutic approaches. Recent investigations on newly differentiated insulin producing cells (IPCs) revealed that they could be derived from embryonic, adult mesenchymal and hematopoietic stem cells. This work was planned to evaluate the role of StemEnhance (Aphanizomenon flos-aquae [AFA] plant extract) in mobilizing naturally occurring bone marrow stem cells as well as in improving streptozotocin-induced diabetic rats. Methods and Results Twenty adult male albino rats were divided into four groups namely the control, the diabetic, the positive control-StemEnhance and the diabetic-StemEnhance groups. After diabetes induction by streptozotocin (STZ), rats received StemEnhance for four weeks. The mean number of blood CD34 immunopositive cells was measured by flowcytometry and random blood sugar was measured weekly. The pancreas was removed from the sacrificed rats and processed for staining with H&E and immunohistochemical staining for CD34+ve and insulin +ve cells. CD34+ve cells increased in the blood after introduction of StemEnhance. CD34+ve cells were observed in the pancreas and the insulin producing cells in the islets of Langerhans were increased from the second to the fourth week of treatment. Blood glucose level improved but it was still higher than the control level after four weeks of StemEnhance treatment. Conclusions This work points to the significant role of StemEnhance in stem cell mobilization and the improvement of diabetes mellitus. PMID:24298369

Relationship between ketamine-induced developmental neurotoxicity and NMDA receptor-mediated calcium influx in neural stem cell-derived neurons.

PubMed

Wang, Cheng; Liu, Fang; Patterson, Tucker A; Paule, Merle G; Slikker, William

2017-05-01

Ketamine, a noncompetitive NMDA receptor antagonist, is used as a general anesthetic and recent data suggest that general anesthetics can cause neuronal damage when exposure occurs during early brain development. To elucidate the underlying mechanisms associated with ketamine-induced neurotoxicity, stem cell-derived models, such as rodent neural stem cells harvested from rat fetuses and/or neural stem cells derived from human induced pluripotent stem cells (iPSC) can be utilized. Prolonged exposure of rodent neural stem cells to clinically-relevant concentrations of ketamine resulted in elevated NMDA receptor levels as indicated by NR1subunit over-expression in neurons. This was associated with enhanced damage in neurons. In contrast, the viability and proliferation rate of undifferentiated neural stem cells were not significantly affected after ketamine exposure. Calcium imaging data indicated that 50μM NMDA did not cause a significant influx of calcium in typical undifferentiated neural stem cells; however, it did produce an immediate elevation of intracellular free Ca 2+ [Ca 2+ ] i in differentiated neurons derived from the same neural stem cells. This paper reviews the literature on this subject and previous findings suggest that prolonged exposure of developing neurons to ketamine produces an increase in NMDA receptor expression (compensatory up-regulation) which allows for a higher/toxic influx of calcium into neurons once ketamine is removed from the system, leading to neuronal cell death likely due to elevated reactive oxygen species generation. The absence of functional NMDA receptors in cultured neural stem cells likely explains why clinically-relevant concentrations of ketamine did not affect undifferentiated neural stem cell viability. Published by Elsevier B.V.

Sepsis induces long-term metabolic and mitochondrial muscle stem cell dysfunction amenable by mesenchymal stem cell therapy

PubMed Central

Rocheteau, P.; Chatre, L.; Briand, D.; Mebarki, M.; Jouvion, G.; Bardon, J.; Crochemore, C.; Serrani, P.; Lecci, P. P.; Latil, M.; Matot, B.; Carlier, P. G.; Latronico, N.; Huchet, C.; Lafoux, A.; Sharshar, T.; Ricchetti, M.; Chrétien, F.

2015-01-01

Sepsis, or systemic inflammatory response syndrome, is the major cause of critical illness resulting in admission to intensive care units. Sepsis is caused by severe infection and is associated with mortality in 60% of cases. Morbidity due to sepsis is complicated by neuromyopathy, and patients face long-term disability due to muscle weakness, energetic dysfunction, proteolysis and muscle wasting. These processes are triggered by pro-inflammatory cytokines and metabolic imbalances and are aggravated by malnutrition and drugs. Skeletal muscle regeneration depends on stem (satellite) cells. Herein we show that mitochondrial and metabolic alterations underlie the sepsis-induced long-term impairment of satellite cells and lead to inefficient muscle regeneration. Engrafting mesenchymal stem cells improves the septic status by decreasing cytokine levels, restoring mitochondrial and metabolic function in satellite cells, and improving muscle strength. These findings indicate that sepsis affects quiescent muscle stem cells and that mesenchymal stem cells might act as a preventive therapeutic approach for sepsis-related morbidity. PMID:26666572

Sepsis induces long-term metabolic and mitochondrial muscle stem cell dysfunction amenable by mesenchymal stem cell therapy.

PubMed

Rocheteau, P; Chatre, L; Briand, D; Mebarki, M; Jouvion, G; Bardon, J; Crochemore, C; Serrani, P; Lecci, P P; Latil, M; Matot, B; Carlier, P G; Latronico, N; Huchet, C; Lafoux, A; Sharshar, T; Ricchetti, M; Chrétien, F

2015-12-15

Sepsis, or systemic inflammatory response syndrome, is the major cause of critical illness resulting in admission to intensive care units. Sepsis is caused by severe infection and is associated with mortality in 60% of cases. Morbidity due to sepsis is complicated by neuromyopathy, and patients face long-term disability due to muscle weakness, energetic dysfunction, proteolysis and muscle wasting. These processes are triggered by pro-inflammatory cytokines and metabolic imbalances and are aggravated by malnutrition and drugs. Skeletal muscle regeneration depends on stem (satellite) cells. Herein we show that mitochondrial and metabolic alterations underlie the sepsis-induced long-term impairment of satellite cells and lead to inefficient muscle regeneration. Engrafting mesenchymal stem cells improves the septic status by decreasing cytokine levels, restoring mitochondrial and metabolic function in satellite cells, and improving muscle strength. These findings indicate that sepsis affects quiescent muscle stem cells and that mesenchymal stem cells might act as a preventive therapeutic approach for sepsis-related morbidity.

The efficacy of polycaprolactone/hydroxyapatite scaffold in combination with mesenchymal stem cells for bone tissue engineering.

PubMed

Chuenjitkuntaworn, Boontharika; Osathanon, Thanaphum; Nowwarote, Nunthawan; Supaphol, Pitt; Pavasant, Prasit

2016-01-01

Major drawbacks of using an autograft are the possibilities of insufficient bony source and patient's morbidity after operation. Bone tissue engineering technology, therefore, has been applied for repairing bony defects. Previous study showed that a novel fabricated 3D-Polycaprolactone/Hydroxyapatite (PCL/HAp) scaffold possessed a good biocompatibility for bone cells. This study aimed to determine the ability of PCL/HAp for supporting cell growth, gene expression, and osteogenic differentiation in three types of mesenchymal stem cells, including bone marrow-derived mesenchymal stem cells (BMSCs), dental pulp stem cells (DPSCs), and adiposed-derived mesenchymal stem cells (ADSCs). These were assessed by cell viability assay (MTT), reverse-transcription polymerase chain reaction (RT-PCR) analysis, alkaline phosphatase activity, and osteogenic differentiation by alizarin red-S staining. The results showed that PCL/HAp scaffold could support growth of all three types of mesenchymal stem cells. In addition, DPSCs with PCL/HAp showed the highest level of calcium deposition compared to other groups. In conclusion, DPSCs exhibited a better compatibility with these scaffolds compared to BMSCs and ADSCs. However, the PCL/HAp could be a good candidate scaffold for all tested mesenchymal stem cells in bone tissue engineering. © 2015 Wiley Periodicals, Inc.

Transplantation of autologous bone marrow-derived mesenchymal stem cells for traumatic brain injury☆

PubMed Central

Jiang, Jindou; Bu, Xingyao; Liu, Meng; Cheng, Peixun

2012-01-01

Results from the present study demonstrated that transplantation of autologous bone marrow-derived mesenchymal stem cells into the lesion site in rat brain significantly ameliorated brain tissue pathological changes and brain edema, attenuated glial cell proliferation, and increased brain-derived neurotrophic factor expression. In addition, the number of cells double-labeled for 5-bromodeoxyuridine/glial fibrillary acidic protein and cells expressing nestin increased. Finally, blood vessels were newly generated, and the rats exhibited improved motor and cognitive functions. These results suggested that transplantation of autologous bone marrow-derived mesenchymal stem cells promoted brain remodeling and improved neurological functions following traumatic brain injury. PMID:25806058

Pluripotent Conversion of Muscle Stem Cells Without Reprogramming Factors or Small Molecules.

PubMed

Bose, Bipasha; Shenoy P, Sudheer

2016-02-01

Muscle derived stem cells (MDSCs) are multipotent stem cells that can differentiate into several lineages including skeletal muscle precursor cells. Here, we show that MDSCs from myostatin null mice (Mstn (-/-) ) can be readily induced into pluripotent stem cells without using reprogramming factors. Microarray studies revealed a strong upregulation of markers like Leukemia Inhibitory factor (LIF) and Leukemia Inhibitory factor receptor (LIFR) in Mstn (-/-) MDSCs as compared to wild type MDSCs (WT-MDSCs). Furthermore when cultured in mouse embryonic stem cell media with LIF for 95 days, Mstn (-/-) MDSCs formed embryonic stem cell (ES) like colonies. We termed such ES like cells as the culture-induced pluripotent stem cells (CiPSC). CiPSCs from Mstn (-/-) MDSCs were phenotypically similar to ESCs, expressed high levels of Oct4, Nanog, Sox2 and SSEA-1, maintained a normal karyotype. Furthermore, CiPSCs formed embryoid bodies and teratomas when injected into immunocompromised mice. In addition, CiPSCs differentiated into somatic cells of all three lineages. We further show that culturing in ES cell media, resulted in hypermethylation and downregulation of BMP2 in Mstn(-/-) MDSCs. Western blot further confirmed a down regulation of BMP2 signaling in Mstn (-/-) MDSCs in supportive of pluripotent reprogramming. Given that down regulation of BMP2 has been shown to induce pluripotency in cells, we propose that lack of myostatin epigenetically reprograms the MDSCs to become pluripotent stem cells. Thus, here we report the successful establishment of ES-like cells from adult stem cells of the non-germline origin under culture-induced conditions without introducing reprogramming genes.

Cisplatin selects for stem-like cells in osteosarcoma by activating Notch signaling

PubMed Central

Yang, Jian; Gao, Tian; Simões, Bruno M.; Eyre, Rachel; Guo, Weichun; Clarke, Robert B.

2016-01-01

Notch signaling regulates normal stem cells and is also thought to regulate cancer stem cells (CSCs). Recent data indicate that Notch signaling plays a role in the development and progression of osteosarcoma, however the regulation of Notch in chemo-resistant stem-like cells has not yet been fully elucidated. In this study we generated cisplatin-resistant osteosarcoma cells by treating them with sub-lethal dose of cisplatin, sufficient to induce DNA damage responses. Cisplatin-resistant osteosarcoma cells exhibited lower proliferation, enhanced spheroid formation and more mesenchymal characteristics than cisplatin-sensitive cells, were enriched for Stro-1+/CD117+ cells and showed increased expression of stem cell-related genes. A similar effect was observed in vivo, and in addition in vivo tumorigenicity was enhanced during serial transplantation. Using several publicly available datasets, we identified that Notch expression was closely associated with osteosarcoma stem cells and chemotherapy resistance. We confirmed that cisplatin-induced enrichment of osteosarcoma stem cells was mediated through Notch signaling in vitro, and immunohistochemistry showed that cleaved Notch1 (NICD1) positive cells were significantly increased in a relapsed xenograft which had received cisplatin treatment. Furthermore, pretreatment with a γ-secretase inhibitor (GSI) to prevent Notch signalling inhibited cisplatin-enriched osteosarcoma stem cell activity in vitro, including Stro-1+/CD117+ double positive cells and spheroid formation capacity. The Notch inhibitor DAPT also prevented tumor recurrence in resistant xenograft tumors. Overall, our results show that cisplatin induces the enrichment of osteosarcoma stem-like cells through Notch signaling, and targeted inactivation of Notch may be useful for the elimination of CSCs and overcoming drug resistance. PMID:27102300

Concise Review: Pluripotent Stem Cell-Based Regenerative Applications for Failing β-Cell Function

PubMed Central

Holditch, Sara J.; Terzic, Andre

2014-01-01

Diabetes engenders the loss of pancreatic β-cell mass and/or function, resulting in insulin deficiency relative to the metabolic needs of the body. Diabetic care has traditionally relied on pharmacotherapy, exemplified by insulin replacement to target peripheral actions of the hormone. With growing understanding of the pathogenesis of diabetic disease, alternative approaches aiming at repair and restoration of failing β-cell function are increasingly considered as complements to current diabetes therapy regimens. To this end, emphasis is placed on transplantation of exogenous pancreas/islets or artificial islets, enhanced proliferation and maturation of endogenous β cells, prevention of β-cell loss, or fortified renewal of β-like-cell populations from stem cell pools and non-β-cell sources. In light of emerging clinical experiences with human embryonic stem cells and approval of the first in-human trial with induced pluripotent stem cells, in this study we highlight advances in β-cell regeneration strategies with a focus on pluripotent stem cell platforms in the context of translational applications. PMID:24646490

Cellular reprogramming in skin cancer.

PubMed

Song, Ihn Young; Balmain, Allan

2015-06-01

Early primitive stem cells have long been viewed as the cancer cells of origin (tumor initiating target cells) due to their intrinsic features of self-renewal and longevity. However, emerging evidence suggests a surprising capacity for normal committed cells to function as reserve stem cells upon reprogramming as a consequence of tissue damage resulting in inflammation and wound healing. This results in an alternative concept positing that tumors may originate from differentiated cells that can re-acquire stem cell properties due to genetic or epigenetic reprogramming. It is likely that both models are correct, and that a continuum of potential cells of origin exists, ranging from early primitive stem cells to committed progenitor or even terminally differentiated cells. A combination of the nature of the target cell and the specific types of gene mutations introduced determine tumor cell lineage, as well as potential for malignant conversion. Evidence from mouse skin models of carcinogenesis suggests that initiated cells at different stages within a stem cell hierarchy have varying degrees of requirement for reprogramming (e.g. inflammation stimuli), depending on their degree of differentiation. This article will present evidence in favor of these concepts that has been developed from studies of several mouse models of skin carcinogenesis. Copyright © 2014 Elsevier Ltd. All rights reserved.

Prospect of stem cell conditioned medium in regenerative medicine.

PubMed

Pawitan, Jeanne Adiwinata

2014-01-01

Stem cell-derived conditioned medium has a promising prospect to be produced as pharmaceuticals for regenerative medicine. To investigate various methods to obtain stem cell-derived conditioned medium (CM) to get an insight into their prospect of application in various diseases. Systematic review using keywords "stem cell" and "conditioned medium" or "secretome" and "therapy." Data concerning treated conditions/diseases, type of cell that was cultured, medium and supplements to culture the cells, culture condition, CM processing, growth factors and other secretions that were analyzed, method of application, and outcome were noted, grouped, tabulated, and analyzed. Most of CM using studies showed good results. However, the various CM, even when they were derived from the same kind of cells, were produced by different condition, that is, from different passage, culture medium, and culture condition. The growth factor yields of the various types of cells were available in some studies, and the cell number that was needed to produce CM for one application could be computed. Various stem cell-derived conditioned media were tested on various diseases and mostly showed good results. However, standardized methods of production and validations of their use need to be conducted.

A review of human pluripotent stem cell-derived cardiomyocytes for high-throughput drug discovery, cardiotoxicity screening, and publication standards.

PubMed

Mordwinkin, Nicholas M; Burridge, Paul W; Wu, Joseph C

2013-02-01

Drug attrition rates have increased in past years, resulting in growing costs for the pharmaceutical industry and consumers. The reasons for this include the lack of in vitro models that correlate with clinical results and poor preclinical toxicity screening assays. The in vitro production of human cardiac progenitor cells and cardiomyocytes from human pluripotent stem cells provides an amenable source of cells for applications in drug discovery, disease modeling, regenerative medicine, and cardiotoxicity screening. In addition, the ability to derive human-induced pluripotent stem cells from somatic tissues, combined with current high-throughput screening and pharmacogenomics, may help realize the use of these cells to fulfill the potential of personalized medicine. In this review, we discuss the use of pluripotent stem cell-derived cardiomyocytes for drug discovery and cardiotoxicity screening, as well as current hurdles that must be overcome for wider clinical applications of this promising approach.

Commentary: on bone marrow stem cells and openmindedness.

PubMed

Mezey, Eva

2004-02-01

Several lines of evidence support the concept that pluripotent stem cells reside in the hematopoietic system of adults, but each has been questioned for valid reasons. Thus, the results reported to date after infusion of bone marrow stem cells, may be due to cell fusion, non-physiological de-differentiation and subsequent differentiation to lineages directed by the culture environment, microchimerism, or transdifferentiation. Several authors have suggested complex ways of investigating each of these possibilities, but in no case are any of the suggested protocols complete, nor will they rule out other possible causes of the results observed to date. Determining the nature, origin, and characteristics of adult cells is important and interesting, but the important question at this time is not what happens physiologically, but what we can do with these cells therapeutically. Research addressing therapeutic endpoints now takes a pivotal position in studies of nonembryonic stem cells.

Isolation and Propagation of Mesenchymal Stem Cells from the Lacrimal Gland

PubMed Central

You, Samantha; Kublin, Claire L.; Avidan, Orna; Miyasaki, David

2011-01-01

Purpose. Previously, it was reported that the murine lacrimal gland is capable of repair after experimentally induced injury and that the number of stem/progenitor cells was increased during the repair phase (2–3 days after injury). The aim of the present study was to determine whether these cells can be isolated from the lacrimal gland and propagated in vitro. Methods. Lacrimal gland injury was induced by injection of interleukin (IL)-1, and injection of saline vehicle served as control. Two and half days after injection, the lacrimal glands were removed and used to prepare explants or acinar cells for tissue culture. Cells derived from the explants and the acinar cells were grown in DMEM supplemented with 10% fetal bovine serum. Cells were stained for the stem cells markers, nestin, vimentin, ABCG2, and Sca-1. Cell proliferation was measured using an antibody against Ki67 or a cell-counting kit. The adipogenic capability of these cells was also tested in vitro. Results. Results show that nestin-positive cells can be isolated from IL-1–injected, but not saline-injected, lacrimal glands. A population of nestin-positive cells was also positive for vimentin, an intermediate filament protein expressed by mesenchymal cells. In addition, cultured cells expressed two other markers of stem cells, ABCG2 and Sca-1. These cells proliferated in vitro and can be induced to form adipocytes, attesting to their mesenchymal stem cell property. Conclusions. Murine lacrimal glands contain mesenchymal stem cells that seem to play a pivotal role in tissue repair. PMID:21178145

Telomerase-immortalized non-malignant human prostate epithelial cells retain the properties of multipotent stem cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li Hongzhen; Zhou Jianjun; Miki, Jun

2008-01-01

Understanding prostate stem cells may provide insight into the origin of prostate cancer. Primary cells have been cultured from human prostate tissue but they usually survive only 15-20 population doublings before undergoing senescence. We report here that RC-170N/h/clone 7 cells, a clonal cell line from hTERT-immortalized primary non-malignant tissue-derived human prostate epithelial cell line (RC170N/h), retain multipotent stem cell properties. The RC-170N/h/clone 7 cells expressed a human embryonic stem cell marker, Oct-4, and potential prostate epithelial stem cell markers, CD133, integrin {alpha}2{beta}1{sup hi} and CD44. The RC-170N/h/clone 7 cells proliferated in KGM and Dulbecco's Modified Eagle Medium with 10% fetalmore » bovine serum and 5 {mu}g/ml insulin (DMEM + 10% FBS + Ins.) medium, and differentiated into epithelial stem cells that expressed epithelial cell markers, including CK5/14, CD44, p63 and cytokeratin 18 (CK18); as well as the mesenchymal cell markers, vimentin, desmin; the neuron and neuroendocrine cell marker, chromogranin A. Furthermore the RC170 N/h/clone 7 cells differentiated into multi tissues when transplanted into the sub-renal capsule and subcutaneously of NOD-SCID mice. The results indicate that RC170N/h/clone 7 cells retain the properties of multipotent stem cells and will be useful as a novel cell model for studying the mechanisms of human prostate stem cell differentiation and transformation.« less

Stem cell exhaustion due to Runx1 deficiency is prevented by Evi5 activation in leukemogenesis

PubMed Central

Jacob, Bindya; Yamashita, Namiko; Wang, Chelsia Qiuxia; Taniuchi, Ichiro; Littman, Dan R.; Asou, Norio

2010-01-01

The RUNX1/AML1 gene is the most frequently mutated gene in human leukemia. Conditional deletion of Runx1 in adult mice results in an increase of hematopoietic stem cells (HSCs), which serve as target cells for leukemia; however, Runx1−/− mice do not develop spontaneous leukemia. Here we show that maintenance of Runx1−/− HSCs is compromised, progressively resulting in HSC exhaustion. In leukemia development, the stem cell exhaustion was rescued by additional genetic changes. Retroviral insertional mutagenesis revealed Evi5 activation as a cooperating genetic alteration and EVI5 overexpression indeed prevented Runx1−/− HSC exhaustion in mice. Moreover, EVI5 was frequently overexpressed in human RUNX1-related leukemias. These results provide insights into the mechanism for maintenance of pre-leukemic stem cells and may provide a novel direction for therapeutic applications. PMID:20008790

A Novel Combinatorial Therapy With Pulp Stem Cells and Granulocyte Colony-Stimulating Factor for Total Pulp Regeneration

PubMed Central

Iohara, Koichiro; Murakami, Masashi; Takeuchi, Norio; Osako, Yohei; Ito, Masataka; Ishizaka, Ryo; Utunomiya, Shinji; Nakamura, Hiroshi; Matsushita, Kenji

2013-01-01

Treatment of deep caries with pulpitis is a major challenge in dentistry. Stem cell therapy represents a potential strategy to regenerate the dentin-pulp complex, enabling conservation and restoration of teeth. The objective of this study was to assess the efficacy and safety of pulp stem cell transplantation as a prelude for the impending clinical trials. Clinical-grade pulp stem cells were isolated and expanded according to good manufacturing practice conditions. The absence of contamination, abnormalities/aberrations in karyotype, and tumor formation after transplantation in an immunodeficient mouse ensured excellent quality control. After autologous transplantation of pulp stem cells with granulocyte-colony stimulating factor (G-CSF) in a dog pulpectomized tooth, regenerated pulp tissue including vasculature and innervation completely filled in the root canal, and regenerated dentin was formed in the coronal part and prevented microleakage up to day 180. Transplantation of pulp stem cells with G-CSF yielded a significantly larger amount of regenerated dentin-pulp complex compared with transplantation of G-CSF or stem cells alone. Also noteworthy was the reduction in the number of inflammatory cells and apoptotic cells and the significant increase in neurite outgrowth compared with results without G-CSF. The transplanted stem cells expressed angiogenic/neurotrophic factors. It is significant that G-CSF together with conditioned medium of pulp stem cells stimulated cell migration and neurite outgrowth, prevented cell death, and promoted immunosuppression in vitro. Furthermore, there was no evidence of toxicity or adverse events. In conclusion, the combinatorial trophic effects of pulp stem cells and G-CSF are of immediate utility for pulp/dentin regeneration, demonstrating the prerequisites of safety and efficacy critical for clinical applications. PMID:23761108

Radiobiological characteristics of cancer stem cells from esophageal cancer cell lines.

PubMed

Wang, Jian-Lin; Yu, Jing-Ping; Sun, Zhi-Qiang; Sun, Su-Ping

2014-12-28

To study the cancer stem cell population in esophageal cancer cell lines KYSE-150 and TE-1 and identify whether the resulting stem-like spheroid cells display cancer stem cells and radiation resistance characteristics. A serum-free medium (SFM) suspension was used to culture esophageal cancer stem cell lines and enrich the esophageal stem-like spheres. A reverse transcription polymerase chain reaction assay was used to detect stem cell gene expression in the spheroid cells. Radiosensitivity of stem-like spheres and parental cells were evaluated by clonogenic assays. Furthermore, different cells after different doses of irradiation were tested to evaluate the change in sphere formation, cell cycle and CD44(+)CD271(+) expression of tumor stem-like spheroid cells using flow cytometry before and after irradiation. The cells were observed to generate an increased number of spheres in SFM with increasing cell passage. Radiation increased the rate of generation of stem-like spheres in both types of cells. The average survival fraction (SF2) of the cultured KYSE-150 compared with TE-1 stem-like spheres after 2 Gy of radiation was 0.81 ± 0.03 vs 0.87 ± 0.01 (P < 0.05), while the average SF2 of KYSE-150 compared with TE-1 parental cells was 0.69 ± 0.04 vs 0.80 ± 0.03, P < 0.05. In the esophageal parental cells, irradiation dose-dependently induced G2 arrest. Stem-like esophageal spheres were resistant to irradiation-induced G2 arrest without significant changes in the percentage population of irradiated stem-like cells. Under irradiation at 0, 4, and 8 Gy, the CD44(+)CD271(+) cell percentage for KYSE150 parental cells was 1.08% ± 0.03% vs 1.29% ± 0.07% vs 1.11% ± 0.09%, respectively; the CD44(+)CD271(+) cell percentage for TE1 parental cells was 1.16% ± 0.11% vs 0.97% ± 0.08% vs 1.45% ± 0.35%, respectively. The differences were not statistically significant. Under irradiation at 0, 4, and 8 Gy, the CD44(+)CD271(+) cell percentage for KYSE-150 stem-like spheres was 35.83% ± 1.23% vs 44.9% ± 1.67% vs 57.77% ± 1.88%, respectively; the CD44(+)CD271(+) cell percentage for TE1 stem-like spheres was 16.07% ± 0.91% vs 22.67% ± 1.12%, 16.07% ± 0.91% vs 33.27% ± 1.07%, respectively. The 4 and 8 Gy irradiated KYSE-150 and TE-1 stem-like spheres were compared with the 0 Gy irradiated group, and the differences were statistically significant (P < 0.05). The KYSE-150 and TE-1 stem-like spheres are more radioresistant than their parental cells which may suggest that cancer stem cells are related to radioresistance.

Retinal Pigment Epithelium Culture;a Potential Source of Retinal Stem Cells

PubMed Central

Akrami, Hassan; Soheili, Zahra-Soheila; Khalooghi, Keynoush; Ahmadieh, Hamid; Rezaie-Kanavi, Mojgan; Samiei, Shahram; Davari, Malihe; Ghaderi, Shima; Sanie-Jahromi, Fatemeh

2009-01-01

Purpose To establish human retinal pigment epithelial (RPE) cell culture as a source for cell replacement therapy in ocular diseases. Methods Human cadaver globes were used to isolate RPE cells. Each globe was cut into several pieces of a few millimeters in size. After removing the sclera and choroid, remaining tissues were washed in phosphate buffer saline and RPE cells were isolated using dispase enzyme solution and cultured in Dulbecco’s Modified Eagle’s Medium: Nutrient Mixture F-12 supplemented with 10% fetal calf serum. Results Primary cultures of RPE cells were established and spheroid colonies related to progenitor/stem cells developed in a number of cultures. The colonies included purely pigmented or mixed pigmented and non-pigmented cells. After multiple cellular passages, several types of photoreceptors and neural-like cells were detected morphologically. Conclusion Cellular plasticity in RPE cell cultures revealed promising results in terms of generation of stem/progenitor cells from human RPE cells. Whether the spheroids and neural-like retinal cells were directly derived from retinal stem cells or offspring of trans-differentiating or de-differentiating RPE cells remains to be answered. PMID:23198062

Therapeutics with SPION-labeled stem cells for the main diseases related to brain aging: a systematic review.

PubMed

Alvarim, Larissa T; Nucci, Leopoldo P; Mamani, Javier B; Marti, Luciana C; Aguiar, Marina F; Silva, Helio R; Silva, Gisele S; Nucci-da-Silva, Mariana P; DelBel, Elaine A; Gamarra, Lionel F

2014-01-01

The increase in clinical trials assessing the efficacy of cell therapy for structural and functional regeneration of the nervous system in diseases related to the aging brain is well known. However, the results are inconclusive as to the best cell type to be used or the best methodology for the homing of these stem cells. This systematic review analyzed published data on SPION (superparamagnetic iron oxide nanoparticle)-labeled stem cells as a therapy for brain diseases, such as ischemic stroke, Parkinson's disease, amyotrophic lateral sclerosis, and dementia. This review highlights the therapeutic role of stem cells in reversing the aging process and the pathophysiology of brain aging, as well as emphasizing nanotechnology as an important tool to monitor stem cell migration in affected regions of the brain.

Label-free detection of surface markers on stem cells by oblique-incidence reflectivity difference microscopy

PubMed Central

Lo, Kai-Yin; Sun, Yung-Shin; Landry, James P.; Zhu, Xiangdong; Deng, Wenbin

2012-01-01

Conventional fluorescent microscopy is routinely used to detect cell surface markers through fluorophore-conjugated antibodies. However, fluorophore-conjugation of antibodies alters binding properties such as strength and specificity of the antibody in ways often uncharacterized. The binding between antibody and antigen might not be in the native situation after such conjugation. Here, we present an oblique-incidence reflectivity difference (OI-RD) microscope as an effective method for label-free, real-time detection of cell surface markers and apply such a technique to analysis of Stage-Specific Embryonic Antigen 1 (SSEA1) on stem cells. Mouse stem cells express SSEA1 on their surfaces and the level of SSEA1 decreases when the cells start to differentiate. In this study, we immobilized mouse stem cells and non-stem cells (control) on a glass surface as a microarray and reacted the cell microarray with unlabeled SSEA1 antibodies. By monitoring the reaction with an OI-RD microscope in real time, we confirmed that the SSEA1 antibodies only bind to the surface of the stem cells while not to the surface of non-stem cells. From the binding curves, we determined the equilibrium dissociation constant (Kd) of the antibody with the SSEA1 markers on the stem cell surface. The results concluded that OI-RD microscope can be used to detect binding affinities between cell surface markers and unlabeled antibodies bound to the cells. The information could be another indicator to determine the cell stages. PMID:21781038

Evolution of Energy Metabolism, Stem Cells and Cancer Stem Cells: How the Warburg and Barker Hypotheses Might Be Linked

PubMed Central

Trosko, James E.; Kang, Kyung-Sun

2012-01-01

The evolutionary transition from single cells to the metazoan forced the appearance of adult stem cells and a hypoxic niche, when oxygenation of the environment forced the appearance of oxidative phosphorylation from that of glycolysis. The prevailing paradigm in the cancer field is that cancers start from the “immortalization” or “re-programming” of a normal, differentiated cell with many mitochondria, that metabolize via oxidative phosphorylation. This paradigm has been challenged with one that assumes that the target cell for carcinogenesis is the normal, immortal adult stem cell, with few mitochondria. This adult organ-specific stem cell is blocked from “mortalizing” or from “programming” to be terminally differentiated. Two hypotheses have been offered to explain cancers, namely, the “stem cell theory” and the “de-differentiation” or “re-programming” theory. This Commentary postulates that the paleochemistry of the oceans, which, initially, provided conditions for life’ s energy to arise via glycolysis, changed to oxidative phosphorylation for life’ s processes. In doing so, stem cells evolved, within hypoxic niches, to protect the species germinal and somatic genomes. This Commentary provides support for the “stem cell theory”, in that cancer cells, which, unlike differentiated cells, have few mitochondria and metabolize via glycolysis. The major argument against the “de-differentiation theory” is that, if re-programming of a differentiated cell to an “induced pluri-potent stem cell” happened in an adult, teratomas, rather than carcinomas, should be the result. PMID:24298354

Scientists' perspectives on the ethical issues of stem cell research.

PubMed

Longstaff, Holly; Schuppli, Catherine A; Preto, Nina; Lafrenière, Darquise; McDonald, Michael

2009-06-01

This paper describes findings from an ethics education project funded by the Canadian Stem Cell Network (SCN). The project is part of a larger research initiative entitled "The Stem Cell Research Environment: Drawing the Evidence and Experience Together". The ethics education study began with a series of focus groups with SCN researchers and trainees as part of a "needs assessment" effort. The purpose of these discussions was to identify the main ethical issues associated with stem cell (SC) research from the perspective of the stem cell community. This paper will focus on five prominent themes that emerged from the focus group data including: (1) the source of stem cells; (2) the power of stem cells; (3) working within a charged research environment; (4) the regulatory context; and (5) ethics training for scientists. Additional discussions are planned with others involved in Canadian stem cell research (e.g., research ethics board members, policy makers) to supplement initial findings. These assessment results combined with existing bioethics literature will ultimately inform a web-based ethics education module for the SCN. We believe that our efforts are important for those analyzing the ethical, legal, and social issues (ELSI) in this area because our in depth understanding of stem cell researcher perspectives will enable us to develop more relevant and effective education material, which in turn should help SC researchers address the important ethical challenges in their area.

Stem cells in asexual reproduction of Enchytraeus japonensis (Oligochaeta, Annelid): proliferation and migration of neoblasts.

PubMed

Sugio, Mutsumi; Yoshida-Noro, Chikako; Ozawa, Kaname; Tochinai, Shin

2012-05-01

Enchytraeus japonensis is a small oligochaete that reproduces mainly asexually by fragmentation (autotomy) and regeneration. As sexual reproduction can also be induced, it is a good animal model for the study of both somatic and germline stem cells. To clarify the features of stem cells in regeneration, we investigated the proliferation and lineage of stem cells in E. japonensis. Neoblasts, which have the morphological characteristics of undifferentiated cells, were found to firmly adhere to the posterior surface of septa in each trunk segment. Also, smaller neoblast-like cells, which are designated as N-cells in this study, were located dorsal to the neoblasts on the septa. By conducting 5-bromo-2'-deoxyuridine (BrdU)-labeling-experiments, we have shown that neoblasts are slow-cycling (or quiescent) in intact growing worms, but proliferate rapidly in response to fragmentation. N-cells proliferate more actively than do neoblasts in intact worms. The results of pulse-chase experiments indicated that neoblast and N-cell lineage mesodermal cells that incorporated BrdU early in regeneration migrated toward the autotomized site to form the mesodermal region of the blastema, while the epidermal and intestinal cells also contributed to the blastema locally near the autotomized site. We have also shown that neoblasts have stem cell characteristics by expressing Ej-vlg2 and by the activity of telomerase during regeneration. Telomerase activity was high in the early stage of regeneration and correlated with the proliferation activity in the neoblast lineage of mesodermal stem cells. Taken together, our results indicate that neoblasts are mesodermal stem cells involved in the regeneration of E. japonensis. © 2012 The Authors. Development, Growth & Differentiation © 2012 Japanese Society of Developmental Biologists.

Hematopoietic stem cell engineering at a crossroads.

PubMed

Rivière, Isabelle; Dunbar, Cynthia E; Sadelain, Michel

2012-02-02

The genetic engineering of hematopoietic stem cells is the basis for potentially treating a large array of hereditary and acquired diseases, and stands as the paradigm for stem cell engineering in general. Recent clinical reports support the formidable promise of this approach but also highlight the limitations of the technologies used to date, which have on occasion resulted in clonal expansion, myelodysplasia, or leukemogenesis. New research directions, predicated on improved vector designs, targeted gene delivery or the therapeutic use of pluripotent stem cells, herald the advent of safer and more effective hematopoietic stem cell therapies that may transform medical practice. In this review, we place these recent advances in perspective, emphasizing the solutions emerging from a wave of new technologies and highlighting the challenges that lie ahead.

"Nutrient-sensing" and self-renewal: O-GlcNAc in a new role.

PubMed

Sharma, Nikita S; Saluja, Ashok K; Banerjee, Sulagna

2018-06-01

Whether embryonic, hematopoietic or cancer stem cells, this metabolic reprogramming is dependent on the nutrient-status and bioenergetic pathways that is influenced by the micro-environmental niches like hypoxia. Thus, the microenvironment plays a vital role in determining the stem cell fate by inducing metabolic reprogramming. Under the influence of the microenvironment, like hypoxia, the stem cells have increased glucose and glutamine uptake which result in activation of hexosamine biosynthesis pathway (HBP) and increased O-GlcNAc Transferase (OGT). The current review is focused on understanding how HBP, a nutrient-sensing pathway (that leads to increased OGT activity) is instrumental in regulating self-renewal not only in embryonic and hematopoietic stem cells (ESC/HSC) but also in cancer stem cells.

Transplantation of neurotrophin-3-transfected bone marrow mesenchymal stem cells for the repair of spinal cord injury.

PubMed

Dong, Yuzhen; Yang, Libin; Yang, Lin; Zhao, Hongxing; Zhang, Chao; Wu, Dapeng

2014-08-15

Bone marrow mesenchymal stem cell transplantation has been shown to be therapeutic in the repair of spinal cord injury. However, the low survival rate of transplanted bone marrow mesenchymal stem cells in vivo remains a problem. Neurotrophin-3 promotes motor neuron survival and it is hypothesized that its transfection can enhance the therapeutic effect. We show that in vitro transfection of neurotrophin-3 gene increases the number of bone marrow mesenchymal stem cells in the region of spinal cord injury. These results indicate that neurotrophin-3 can promote the survival of bone marrow mesenchymal stem cells transplanted into the region of spinal cord injury and potentially enhance the therapeutic effect in the repair of spinal cord injury.

Gene expression profile in mesenchymal stem cells derived from dental tissues and bone marrow

PubMed Central

Kim, Su-Hwan; Kim, Young-Sung; Lee, Su-Yeon; Kim, Kyoung-Hwa; Lee, Yong-Moo; Kim, Won-Kyung

2011-01-01

Purpose The aim of this study is to compare the gene expression profile in mesenchymal stem cells derived from dental tissues and bone marrow for characterization of dental stem cells. Methods We employed GeneChip analysis to the expression levels of approximately 32,321 kinds of transcripts in 5 samples of bone-marrow-derived mesenchymal stem cells (BMSCs) (n=1), periodontal ligament stem cells (PDLSCs) (n=2), and dental pulp stem cells (DPSCs) (n=2). Each cell was sorted by a FACS Vantage Sorter using immunocytochemical staining of the early mesenchymal stem cell surface marker STRO-1 before the microarray analysis. Results We identified 379 up-regulated and 133 down-regulated transcripts in BMSCs, 68 up-regulated and 64 down-regulated transcripts in PDLSCs, and 218 up-regulated and 231 down-regulated transcripts in DPSCs. In addition, anatomical structure development and anatomical structure morphogenesis gene ontology (GO) terms were over-represented in all three different mesenchymal stem cells and GO terms related to blood vessels, and neurons were over-represented only in DPSCs. Conclusions This study demonstrated the genome-wide gene expression patterns of STRO-1+ mesenchymal stem cells derived from dental tissues and bone marrow. The differences among the expression profiles of BMSCs, PDLSCs, and DPSCs were shown, and 999 candidate genes were found to be definitely up- or down-regulated. In addition, GOstat analyses of regulated gene products provided over-represented GO classes. These data provide a first step for discovering molecules key to the characteristics of dental stem cells. PMID:21954424

Bulge Region as a Putative Hair Follicle Stem Cells Niche: A Brief Review

PubMed Central

JOULAI VEIJOUYE, Sanaz; YARI, Abazar; HEIDARI, Fatemeh; SAJEDI, Nayereh; GHOROGHI MOGHANI, Fatemeh; NOBAKHT, Maliheh

2017-01-01

Background: Hair follicle stem cells exist in different sites. Most of the hair follicle stem cells are reside in niche called bulge. Bulge region is located between the opening of sebaceous gland and the attachment site of the arrector pili muscle. Methods: Data were collected using databases and resources of PubMed, Web of Science, Science Direct, Scopus, MEDLINE and their references from the earliest available published to identify English observational studies on hair follicle bulge region. Results: Bulge stem cells are pluripotent with high proliferative capacity. Specific markers allow the bulge cells to be isolated from mouse or human hair follicle. Stem cells isolated from bulge region are label retaining and slow cycling hence these cells are defined as label-retaining cells. Bulge cell populations, due to their plasticity nature are able to differentiate into distinct linage and could contribute in tissue regeneration. Conclusion: The current review discuss about bulge stem cells characteristics and biology including their cycle, location, plasticity, specific markers and regenerative nature. Also the differences between mouse and human hair follicles are investigated. PMID:29026781

Evaluation of porcine stem cell competence for somatic cell nuclear transfer and production of cloned animals.

PubMed

Secher, Jan O; Liu, Ying; Petkov, Stoyan; Luo, Yonglun; Li, Dong; Hall, Vanessa J; Schmidt, Mette; Callesen, Henrik; Bentzon, Jacob F; Sørensen, Charlotte B; Freude, Kristine K; Hyttel, Poul

2017-03-01

Porcine somatic cell nuclear transfer (SCNT) has been used extensively to create genetically modified pigs, but the efficiency of the methodology is still low. It has been hypothesized that pluripotent or multipotent stem cells might result in increased SCNT efficacy as these cells are closer than somatic cells to the epigenetic state found in the blastomeres and therefore need less reprogramming. Our group has worked with porcine SCNT during the last 20 years and here we describe our experience with SCNT of 3 different stem cell lines. The porcine stem cells used were: Induced pluripotent stem cells (iPSCs) created by lentiviral doxycycline-dependent reprogramming and cultered with a GSK3β- and MEK-inhibitor (2i) and leukemia inhibitor factor (LIF) (2i LIF DOX-iPSCs), iPSCs created by a plasmid-based reprogramming and cultured with 2i and fibroblast growth factor (FGF) (2i FGF Pl-iPSCs) and embryonic germ cells (EGCs), which have earlier been characterized as being multipotent. The SCNT efficiencies of these stem cell lines were compared with that of the two fibroblast cell lines from which the iPSC lines were derived. The blastocyst rates for the 2i LIF DOX-iPSCs were 14.7%, for the 2i FGF Pl-iPSC 10.1%, and for the EGCs 34.5% compared with the fibroblast lines yielding 36.7% and 25.2%. The fibroblast- and EGC-derived embryos were used for embryo transfer and produced live offspring at similar low rates of efficiency (3.2 and 4.0%, respectively) and with several instances of malformations. In conclusion, potentially pluripotent porcine stem cells resulted in lower rates of embryonic development upon SCNT than multipotent stem cells and differentiated somatic cells. Copyright © 2017 Elsevier B.V. All rights reserved.

Distinct Responses of Stem Cells to Telomere Uncapping-A Potential Strategy to Improve the Safety of Cell Therapy.

PubMed

Liu, Chang Ching; Ma, Dong Liang; Yan, Ting-Dong; Fan, XiuBo; Poon, Zhiyong; Poon, Lai-Fong; Goh, Su-Ann; Rozen, Steve G; Hwang, William Ying Khee; Tergaonkar, Vinay; Tan, Patrick; Ghosh, Sujoy; Virshup, David M; Goh, Eyleen L K; Li, Shang

2016-10-01

In most human somatic cells, the lack of telomerase activity results in progressive telomere shortening during each cell division. Eventually, DNA damage responses triggered by critically short telomeres induce an irreversible cell cycle arrest termed replicative senescence. However, the cellular responses of human pluripotent stem cells to telomere uncapping remain unknown. We generated telomerase knockout human embryonic stem (ES) cells through gene targeting. Telomerase inactivation in ES cells results in progressive telomere shortening. Telomere DNA damage in ES cells and neural progenitor cells induces rapid apoptosis when telomeres are uncapped, in contrast to fibroblast cells that enter a state of replicative senescence. Significantly, telomerase inactivation limits the proliferation capacity of human ES cells without affecting their pluripotency. By targeting telomerase activity, we can functionally separate the two unique properties of human pluripotent stem cells, namely unlimited self-renewal and pluripotency. We show that the potential of ES cells to form teratomas in vivo is dictated by their telomere length. By controlling telomere length of ES cells through telomerase inactivation, we can inhibit teratoma formation and potentially improve the safety of cell therapies involving terminally differentiated cells as well as specific progenitor cells that do not require sustained cellular proliferation in vivo, and thus sustained telomerase activity. Stem Cells 2016;34:2471-2484. © 2016 AlphaMed Press.

A systematic review on the role of environmental toxicants in stem cells aging.

PubMed

Hodjat, Mahshid; Rezvanfar, Mohammad Amin; Abdollahi, Mohammad

2015-12-01

Stem cells are an important target for environmental toxicants. As they are the main source for replenishing of organs in the body, any changes in their normal function could affect the regenerative potential of organs, leading to the appearance of age-related disease and acceleration of the aging process. Environmental toxicants could exert their adverse effect on stem cell function via multiple cellular and molecular mechanisms, resulting in changes in the stem cell differentiation fate and cell transformation, and reduced self-renewal capacity, as well as induction of stress-induced cellular senescence. The present review focuses on the effect of environmental toxicants on stem cell function associated with the aging process. We categorized environmental toxicants according to their preferred molecular mechanism of action on stem cells, including changes in genomic, epigenomic, and proteomic levels and enhancing oxidative stress. Pesticides, tobacco smoke, radiation and heavy metals are well-studied toxicants that cause stem cell dysfunction via induction of oxidative stress. Transgenerational epigenetic changes are the most important effects of a variety of toxicants on germ cells and embryos that are heritable and could affect health in the next several generations. A better understanding of the underlying mechanisms of toxicant-induced stem cell aging will help us to develop therapeutic intervention strategies against environmental aging. Meanwhile, more efforts are required to find the direct in vivo relationship between adverse effect of environmental toxicants and stem cell aging, leading to organismal aging. Copyright © 2015 Elsevier Ltd. All rights reserved.

Allogenic banking of dental pulp stem cells for innovative therapeutics.

PubMed

Collart-Dutilleul, Pierre-Yves; Chaubron, Franck; De Vos, John; Cuisinier, Frédéric J

2015-08-26

Medical research in regenerative medicine and cell-based therapy has brought encouraging perspectives for the use of stem cells in clinical trials. Multiple types of stem cells, from progenitors to pluripotent stem cells, have been investigated. Among these, dental pulp stem cells (DPSCs) are mesenchymal multipotent cells coming from the dental pulp, which is the soft tissue within teeth. They represent an interesting adult stem cell source because they are recovered in large amount in dental pulps with non-invasive techniques compared to other adult stem cell sources. DPSCs can be obtained from discarded teeth, especially wisdom teeth extracted for orthodontic reasons. To shift from promising preclinical results to therapeutic applications to human, DPSCs must be prepared in clinical grade lots and transformed into advanced therapy medicinal products (ATMP). As the production of patient-specific stem cells is costly and time-consuming, allogenic biobanking of clinical grade human leukocyte antigen (HLA)-typed DPSC lines provides efficient innovative therapeutic products. DPSC biobanks represent industrial and therapeutic innovations by using discarded biological tissues (dental pulps) as a source of mesenchymal stem cells to produce and store, in good manufacturing practice (GMP) conditions, DPSC therapeutic batches. In this review, we discuss about the challenges to transfer biological samples from a donor to HLA-typed DPSC therapeutic lots, following regulations, GMP guidelines and ethical principles. We also present some clinical applications, for which there is no efficient therapeutics so far, but that DPSCs-based ATMP could potentially treat.

Allogenic banking of dental pulp stem cells for innovative therapeutics

PubMed Central

Collart-Dutilleul, Pierre-Yves; Chaubron, Franck; De Vos, John; Cuisinier, Frédéric J

2015-01-01

Medical research in regenerative medicine and cell-based therapy has brought encouraging perspectives for the use of stem cells in clinical trials. Multiple types of stem cells, from progenitors to pluripotent stem cells, have been investigated. Among these, dental pulp stem cells (DPSCs) are mesenchymal multipotent cells coming from the dental pulp, which is the soft tissue within teeth. They represent an interesting adult stem cell source because they are recovered in large amount in dental pulps with non-invasive techniques compared to other adult stem cell sources. DPSCs can be obtained from discarded teeth, especially wisdom teeth extracted for orthodontic reasons. To shift from promising preclinical results to therapeutic applications to human, DPSCs must be prepared in clinical grade lots and transformed into advanced therapy medicinal products (ATMP). As the production of patient-specific stem cells is costly and time-consuming, allogenic biobanking of clinical grade human leukocyte antigen (HLA)-typed DPSC lines provides efficient innovative therapeutic products. DPSC biobanks represent industrial and therapeutic innovations by using discarded biological tissues (dental pulps) as a source of mesenchymal stem cells to produce and store, in good manufacturing practice (GMP) conditions, DPSC therapeutic batches. In this review, we discuss about the challenges to transfer biological samples from a donor to HLA-typed DPSC therapeutic lots, following regulations, GMP guidelines and ethical principles. We also present some clinical applications, for which there is no efficient therapeutics so far, but that DPSCs-based ATMP could potentially treat. PMID:26328017

The CCR4-NOT complex mediates deadenylation and degradation of stem cell mRNAs and promotes planarian stem cell differentiation.

PubMed

Solana, Jordi; Gamberi, Chiara; Mihaylova, Yuliana; Grosswendt, Stefanie; Chen, Chen; Lasko, Paul; Rajewsky, Nikolaus; Aboobaker, A Aziz

2013-01-01

Post-transcriptional regulatory mechanisms are of fundamental importance to form robust genetic networks, but their roles in stem cell pluripotency remain poorly understood. Here, we use freshwater planarians as a model system to investigate this and uncover a role for CCR4-NOT mediated deadenylation of mRNAs in stem cell differentiation. Planarian adult stem cells, the so-called neoblasts, drive the almost unlimited regenerative capabilities of planarians and allow their ongoing homeostatic tissue turnover. While many genes have been demonstrated to be required for these processes, currently almost no mechanistic insight is available into their regulation. We show that knockdown of planarian Not1, the CCR4-NOT deadenylating complex scaffolding subunit, abrogates regeneration and normal homeostasis. This abrogation is primarily due to severe impairment of their differentiation potential. We describe a stem cell specific increase in the mRNA levels of key neoblast genes after Smed-not1 knock down, consistent with a role of the CCR4-NOT complex in degradation of neoblast mRNAs upon the onset of differentiation. We also observe a stem cell specific increase in the frequency of longer poly(A) tails in these same mRNAs, showing that stem cells after Smed-not1 knock down fail to differentiate as they accumulate populations of transcripts with longer poly(A) tails. As other transcripts are unaffected our data hint at a targeted regulation of these key stem cell mRNAs by post-transcriptional regulators such as RNA-binding proteins or microRNAs. Together, our results show that the CCR4-NOT complex is crucial for stem cell differentiation and controls stem cell-specific degradation of mRNAs, thus providing clear mechanistic insight into this aspect of neoblast biology.

The CCR4-NOT Complex Mediates Deadenylation and Degradation of Stem Cell mRNAs and Promotes Planarian Stem Cell Differentiation

PubMed Central

Solana, Jordi; Gamberi, Chiara; Mihaylova, Yuliana; Grosswendt, Stefanie; Chen, Chen; Lasko, Paul; Rajewsky, Nikolaus; Aboobaker, A. Aziz

2013-01-01

Post-transcriptional regulatory mechanisms are of fundamental importance to form robust genetic networks, but their roles in stem cell pluripotency remain poorly understood. Here, we use freshwater planarians as a model system to investigate this and uncover a role for CCR4-NOT mediated deadenylation of mRNAs in stem cell differentiation. Planarian adult stem cells, the so-called neoblasts, drive the almost unlimited regenerative capabilities of planarians and allow their ongoing homeostatic tissue turnover. While many genes have been demonstrated to be required for these processes, currently almost no mechanistic insight is available into their regulation. We show that knockdown of planarian Not1, the CCR4-NOT deadenylating complex scaffolding subunit, abrogates regeneration and normal homeostasis. This abrogation is primarily due to severe impairment of their differentiation potential. We describe a stem cell specific increase in the mRNA levels of key neoblast genes after Smed-not1 knock down, consistent with a role of the CCR4-NOT complex in degradation of neoblast mRNAs upon the onset of differentiation. We also observe a stem cell specific increase in the frequency of longer poly(A) tails in these same mRNAs, showing that stem cells after Smed-not1 knock down fail to differentiate as they accumulate populations of transcripts with longer poly(A) tails. As other transcripts are unaffected our data hint at a targeted regulation of these key stem cell mRNAs by post-transcriptional regulators such as RNA-binding proteins or microRNAs. Together, our results show that the CCR4-NOT complex is crucial for stem cell differentiation and controls stem cell-specific degradation of mRNAs, thus providing clear mechanistic insight into this aspect of neoblast biology. PMID:24367277

Effect of stromal-cell-derived factor 1 on stem-cell homing and tissue regeneration in ischaemic cardiomyopathy

NASA Technical Reports Server (NTRS)

Askari, Arman T.; Unzek, Samuel; Popovic, Zoran B.; Goldman, Corey K.; Forudi, Farhad; Kiedrowski, Matthew; Rovner, Aleksandr; Ellis, Stephen G.; Thomas, James D.; DiCorleto, Paul E.;

A Unique Opportunity to Test Whether Cell Fusion is a Mechanism of Breast Cancer Metastasis

DTIC Science & Technology

2015-06-01

conditions for T47D and human mesenchymal stem cell populations. As a result we have been able to conduct our first co-culture experiments to determine...spontaneously and reliably with mesenchymal stem cells . We found that fusion occurs more frequently with hypoxia and that one means by which...in hypoxic conditions, we decided to investigate whether the mechanism of breast cancer cell fusion with mesenchymal stem /multipotent stromal cells

Efficient expansion of human keratinocyte stem/progenitor cells carrying a transgene with lentiviral vector

PubMed Central

2013-01-01

Introduction The development of an appropriate procedure for lentiviral gene transduction into keratinocyte stem cells is crucial for stem cell biology and regenerative medicine for genetic disorders of the skin. However, there is little information available on the efficiency of lentiviral transduction into human keratinocyte stem/progenitor cells and the effects of gene transduction procedures on growth potential of the stem cells by systematic assessment. Methods In this study, we explored the conditions for efficient expansion of human keratinocyte stem/progenitor cells carrying a transgene with a lentiviral vector, by using the culture of keratinocytes on a feeder layer of 3 T3 mouse fibroblasts. The gene transduction and expansion of keratinocytes carrying a transgene were analyzed by Western blotting, quantitative PCR, and flow cytometry. Results Polybrene (hexadiamine bromide) markedly enhanced the efficiency of lentiviral gene transduction, but negatively affected the maintenance of the keratinocyte stem/progenitor cells at a concentration higher than 5 μg/ml. Rho-assiciated kinase (ROCK) inhibitor Y-27632, a small molecule which enhanced keratinocyte proliferation, significantly interfered with the lentiviral transduction into cultured human keratinocytes. However, a suitable combination of polybrene and Y-27632 effectively expanded keratinocytes carrying a transgene. Conclusions This study provides information for effective expansion of cultured human keratinocyte stem/progenitor cells carrying a transgene. This point is particularly significant for the application of genetically modified keratinocyte stem/progenitor stem cells in regenerative medicine. PMID:24406242

Human immature dental pulp stem cells (hIDPSCs), their application to cell therapy and bioengineering: an analysis by systematic revision of the last decade of literature.

PubMed

de Souza, Priscilla Vianna; Alves, Fabiana Bucholdz Teixeira; Costa Ayub, Cristina Lucia Sant'Ana; de Miranda Soares, Maria Albertina; Gomes, Jose Rosa

2013-12-01

During recent years, attention has been given to the potential of therapeutic approaches using stem cells obtained from dental pulp tissue. The aim of this study, therefore, was to give an overview of the papers produced during the last 10 years that have described the use of stem cells obtained from human deciduous teeth in cell therapy or bioengineering. The PubMed database was investigated from January 2002 until July 2011 and the papers published during this period were analyzed according to criteria previously established, using the methodology of systematic review. The measurements were done using "stem cell" as the primary keyword, and "human deciduous teeth dental pulp cell" and "human exfoliated deciduous teeth" as the secondary keywords. Four hundred and seventy-five papers were found. The first screening resulted in 276 papers, from which 84 papers were selected. However, only 11 of them attained the aim proposed in our approach. There were few scientific studies related to direct therapeutic application using stem cells of human deciduous teeth and none of them had been applied to humans. However, the results indicated important and promising applications of the pulp stem-cells in cell therapy and bioengineering as demonstrated by studies in animal models of muscular dystrophy, Parkison's disease, and lupus erythematosus. Copyright © 2013 Wiley Periodicals, Inc.

STAT3 as a potential therapeutic target in ALDH+ and CD44+/CD24+ stem cell-like pancreatic cancer cells.

PubMed

Lin, Li; Jou, David; Wang, Yina; Ma, Haiyan; Liu, Tianshu; Fuchs, James; Li, Pui-Kai; Lü, Jiagao; Li, Chenglong; Lin, Jiayuh

2016-12-01

Persistent activation of signal transducers and activators of transcription 3 (STAT3) is commonly detected in many types of cancer including pancreatic cancer. Whether STAT3 is activated in stem cell-like pancreatic cancer cells and the effect of STAT3 inhibition, is still unknown. Flow cytometry was used to isolate pancreatic cancer stem-like cells which are identified by both aldehyde dehydrogenase (ALDH)-positive (ALDH+) as well as cluster of differentiation (CD) 44-positive/CD24-positive subpopulations (CD44+/CD24+). STAT3 activation and the effects of STAT3 inhibition by STAT3 inhibitors, LLL12, FLLL32, and Stattic in ALDH+ and CD44+/CD24+ cells were examined. Our results showed that ALDH+ and CD44+/CD24+ pancreatic cancer stem-like cells expressed higher levels of phosphorylated STAT3, an active form of STAT3, compared to ALDH-negative (ALDH-) and CD44-negative/CD24-negative (CD44-/CD24-) pancreatic cancer cells, suggesting that STAT3 is activated in pancreatic cancer stem-like cells. Small molecular STAT3 inhibitors inhibited STAT3 phosphorylation, STAT3 downstream target gene expression, cell viability, and tumorsphere formation in ALDH+ and CD44+/CD24+ cells. Our results indicate that STAT3 is a novel therapeutic target in pancreatic cancer stem-like cells and inhibition of activated STAT3 in these cells by STAT3 inhibitors may offer an effective treatment for pancreatic cancer.

Chemical Activation of the Hypoxia-Inducible Factor Reversibly Reduces Tendon Stem Cell Proliferation, Inhibits Their Differentiation, and Maintains Cell Undifferentiation

PubMed Central

Creo, Pasquale; Bergante, Sonia; Conforti, Erika; Banfi, Giuseppe

2018-01-01

Adult stem cell-based therapeutic approaches for tissue regeneration have been proposed for several years. However, adult stem cells are usually limited in number and difficult to be expanded in vitro, and they usually tend to quickly lose their potency with passages, as they differentiate and become senescent. Culturing stem cells under reduced oxygen tensions (below 21%) has been proposed as a tool to increase cell proliferation, but many studies reported opposite effects. In particular, cell response to hypoxia seems to be very stem cell type specific. Nonetheless, it is clear that a major role in this process is played by the hypoxia inducible factor (HIF), the master regulator of cell response to oxygen deprivation, which affects cell metabolism and differentiation. Herein, we report that a chemical activation of HIF in human tendon stem cells reduces their proliferation and inhibits their differentiation in a reversible and dose-dependent manner. These results support the notion that hypoxia, by activating HIF, plays a crucial role in preserving stem cells in an undifferentiated state in the “hypoxic niches” present in the tissue in which they reside before migrating in more oxygenated areas to heal a damaged tissue. PMID:29713352

Types of Stem Cells

MedlinePlus

... Cell Glossary Search Toggle Nav Types of Stem Cells Stem cells are the foundation from which all ... About Stem Cells > Types of Stem Cells Stem cells Stem cells are the foundation for every organ ...

The molecular signature of muscle stem cells is driven by nutrient availability and innate cell metabolism.

PubMed

Ryall, James G; Lynch, Gordon S

2018-07-01

To discuss how innate muscle stem-cell metabolism and nutrient availability can provide temporal regulation of chromatin accessibility and transcription. Fluorescence-activated cell sorting coupled with whole transcriptome sequencing revealed for the first time that quiescent and proliferating skeletal muscle stem cells exhibit a process of metabolic reprogramming, from fatty-acid oxidation during quiescence to glycolysis during proliferation. Using a combination of immunofluorescence and chromatin immunoprecipitation sequencing, this shift in metabolism has been linked to altered availability of key metabolites essential for histone (de)acetylation and (de)methylation, including acetyl-CoA, s-adenosylmethionine and α-ketoglutarate. Importantly, these changes in metabolite availability have been linked to muscle stem-cell function. Together, these results provide greater insight into how muscle stem cells interact with their local environment, with important implications for metabolic diseases, skeletal muscle regeneration and cell-transplantation therapies.

Agonism of Wnt/β-catenin signaling promotes mesenchymal stem cell (MSC) expansion

PubMed Central

Hoffman, Michael D.; Benoit, Danielle S.W.

2014-01-01

Promoting mesenchymal stem cell (MSC) proliferation has numerous applications in stem cell therapies, particularly in the area of regenerative medicine. In order for cell-based regenerative approaches to be realized, MSC proliferation must be achieved in a controlled manner without compromising stem cell differentiation capacities. Here we demonstrate that 6-bromoindirubin-3’-oxime (BIO) increases MSC β-catenin activity 106-fold and stem cell-associated gene expression ~33-fold respectively over untreated controls. Subsequently, BIO treatment increases MSC populations 1.8-fold in typical 2D culture conditions, as well as 1.3-fold when encapsulated within hydrogels compared to untreated cells. Furthermore, we demonstrate that BIO treatment does not reduce MSC multipotency, where MSCs maintain their ability to differentiate into osteoblasts, chondrocytes, and adipocytes using standard conditions. Taken together, our results demonstrate BIOs potential utility as a proliferative agent for cell transplantation and tissue regeneration. PMID:23554411

Ground-state transcriptional requirements for skin-derived precursors.

PubMed

Suflita, Michael T; Pfaltzgraff, Elise R; Mundell, Nathan A; Pevny, Larysa H; Labosky, Patricia A

2013-06-15

Skin-derived precursors (SKPs) are an attractive stem cell model for cell-based therapies. SKPs can be readily generated from embryonic and adult mice and adult humans, exhibit a high degree of multipotency, and have the potential to serve as a patient autologous stem cell. The advancement of these cells toward therapeutic use depends on the ability to control precisely the self-renewal and differentiation of SKPs. Here we show that two well-known stem cell factors, Foxd3 and Sox2, are critical regulators of the stem cell properties of SKPs. Deletion of Foxd3 completely abolishes the sphere-forming potential of these cells. In the absence of Sox2, SKP spheres can be formed, but with reduced size and frequency. Our results provide entry points into the gene regulatory networks dictating SKP behavior, and pave the way for future studies on a therapeutically relevant stem cell.

Ground-State Transcriptional Requirements for Skin-Derived Precursors

PubMed Central

Suflita, Michael T.; Pfaltzgraff, Elise R.; Mundell, Nathan A.; Pevny, Larysa H.

2013-01-01

Skin-derived precursors (SKPs) are an attractive stem cell model for cell-based therapies. SKPs can be readily generated from embryonic and adult mice and adult humans, exhibit a high degree of multipotency, and have the potential to serve as a patient autologous stem cell. The advancement of these cells toward therapeutic use depends on the ability to control precisely the self-renewal and differentiation of SKPs. Here we show that two well-known stem cell factors, Foxd3 and Sox2, are critical regulators of the stem cell properties of SKPs. Deletion of Foxd3 completely abolishes the sphere-forming potential of these cells. In the absence of Sox2, SKP spheres can be formed, but with reduced size and frequency. Our results provide entry points into the gene regulatory networks dictating SKP behavior, and pave the way for future studies on a therapeutically relevant stem cell. PMID:23316968

Predicting gene regulatory networks by combining spatial and temporal gene expression data in Arabidopsis root stem cells

PubMed Central

de Luis Balaguer, Maria Angels; Fisher, Adam P.; Clark, Natalie M.; Fernandez-Espinosa, Maria Guadalupe; Möller, Barbara K.; Weijers, Dolf; Williams, Cranos; Lorenzo, Oscar; Sozzani, Rosangela

2017-01-01

Identifying the transcription factors (TFs) and associated networks involved in stem cell regulation is essential for understanding the initiation and growth of plant tissues and organs. Although many TFs have been shown to have a role in the Arabidopsis root stem cells, a comprehensive view of the transcriptional signature of the stem cells is lacking. In this work, we used spatial and temporal transcriptomic data to predict interactions among the genes involved in stem cell regulation. To accomplish this, we transcriptionally profiled several stem cell populations and developed a gene regulatory network inference algorithm that combines clustering with dynamic Bayesian network inference. We leveraged the topology of our networks to infer potential major regulators. Specifically, through mathematical modeling and experimental validation, we identified PERIANTHIA (PAN) as an important molecular regulator of quiescent center function. The results presented in this work show that our combination of molecular biology, computational biology, and mathematical modeling is an efficient approach to identify candidate factors that function in the stem cells. PMID:28827319

Diabetes and Stem Cell Function

PubMed Central

Fujimaki, Shin; Wakabayashi, Tamami; Takemasa, Tohru; Asashima, Makoto; Kuwabara, Tomoko

2015-01-01

Diabetes mellitus is one of the most common serious metabolic diseases that results in hyperglycemia due to defects of insulin secretion or insulin action or both. The present review focuses on the alterations to the diabetic neuronal tissues and skeletal muscle, including stem cells in both tissues, and the preventive effects of physical activity on diabetes. Diabetes is associated with various nervous disorders, such as cognitive deficits, depression, and Alzheimer's disease, and that may be caused by neural stem cell dysfunction. Additionally, diabetes induces skeletal muscle atrophy, the impairment of energy metabolism, and muscle weakness. Similar to neural stem cells, the proliferation and differentiation are attenuated in skeletal muscle stem cells, termed satellite cells. However, physical activity is very useful for preventing the diabetic alteration to the neuronal tissues and skeletal muscle. Physical activity improves neurogenic capacity of neural stem cells and the proliferative and differentiative abilities of satellite cells. The present review proposes physical activity as a useful measure for the patients in diabetes to improve the physiological functions and to maintain their quality of life. It further discusses the use of stem cell-based approaches in the context of diabetes treatment. PMID:26075247

Comparative Chondrogenesis of Human Cell Sources in 3D Scaffolds

PubMed Central

Tıg̑lı, R. Seda; Ghosh, Sourabh; Laha, Michael M.; Shevde, Nirupama K.; Daheron, Laurence; Gimble, Jeffrey; Gümüşdereliog̑lu, Menemşe; Kaplan, David L.

2009-01-01

Cartilage tissue can be engineered by starting from a diversity of cell sources, including stem-cell based and primary cell-based platforms. Selecting an appropriate cell source for the process of cartilage tissue engineering or repair is critical and challenging due to the variety of cell options available. In this study, cellular responses of isolated human chondrocytes, human embryonic stem cells and mesenchymal stem cells (MSCs) derived from three sources, human embryonic stem cells, bone marrow and adipose tissue, were assessed for chondrogenic potential in 3D culture. All cell sources were characterized by FACS analysis to compare expression of some surface markers. The cells were differentiated in two different biomaterial matrices, silk and chitosan scaffolds, in the presence and absence of bone morphogenetic protein 6 (BMP-6) along with the standard chondrogenic differentiating factors. Embryonic stem cells derived MSCs showed unique characteristics with preserved chondrogenic phenotype in both scaffolds with regard to chondrogenesis, as determined by real time RT-PCR, histological and microscopic analyses. After 4 weeks of cultivation, embryonic stem cells derived MSCs were promising for chondrogenesis, particularly in the silk scaffolds with BMP-6. The results suggest that cell source differences are important to consider with regard to chondrogenic outcomes and with the variables addressed here, the human embryonic stem cells derived MSCs were the preferred cell source. PMID:19382119

Mesenchymal stem cells attenuate blood-brain barrier leakage after cerebral ischemia in mice.

PubMed

Cheng, Zhuo; Wang, Liping; Qu, Meijie; Liang, Huaibin; Li, Wanlu; Li, Yongfang; Deng, Lidong; Zhang, Zhijun; Yang, Guo-Yuan

2018-05-03

Ischemic stroke induced matrixmetallo-proteinase-9 (MMP-9) upregulation, which increased blood-brain barrier permeability. Studies demonstrated that mesenchymal stem cell therapy protected blood-brain barrier disruption from several cerebrovascular diseases. However, the underlying mechanism was largely unknown. We therefore hypothesized that mesenchymal stem cells reduced blood-brain barrier destruction by inhibiting matrixmetallo-proteinase-9 and it was related to intercellular adhesion molecule-1 (ICAM-1). Adult ICR male mice (n = 118) underwent 90-min middle cerebral artery occlusion and received 2 × 10 5 mesenchymal stem cell transplantation. Neurobehavioral outcome, infarct volume, and blood-brain barrier permeability were measured after ischemia. The relationship between myeloperoxidase (MPO) activity and ICAM-1 release was further determined. We found that intracranial injection of mesenchymal stem cells reduced infarct volume and improved behavioral function in experimental stroke models (p < 0.05). IgG leakage, tight junction protein loss, and inflammatory cytokines IL-1β, IL-6, and TNF-α reduced in mesenchymal stem cell-treated mice compared to the control group following ischemia (p < 0.05). After transplantation, MMP-9 was decreased in protein and activity levels as compared with controls (p < 0.05). Furthermore, myeloperoxidase-positive cells and myeloperoxidase activity were decreased in mesenchymal stem cell-treated mice (p < 0.05). The results showed that mesenchymal stem cell therapy attenuated blood-brain barrier disruption in mice after ischemia. Mesenchymal stem cells attenuated the upward trend of MMP-9 and potentially via downregulating ICAM-1 in endothelial cells. Adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK) pathway may influence MMP-9 expression of neutrophils and resident cells, and ICAM-1 acted as a key factor in the paracrine actions of mesenchymal stem cell.

Temozolomide downregulates P-glycoprotein expression in glioblastoma stem cells by interfering with the Wnt3a/glycogen synthase-3 kinase/β-catenin pathway

PubMed Central

Riganti, Chiara; Salaroglio, Iris Chiara; Caldera, Valentina; Campia, Ivana; Kopecka, Joanna; Mellai, Marta; Annovazzi, Laura; Bosia, Amalia; Ghigo, Dario; Schiffer, Davide

2013-01-01

Background Glioblastoma multiforme stem cells display a highly chemoresistant phenotype, whose molecular basis is poorly known. We aim to clarify this issue and to investigate the effects of temozolomide on chemoresistant stem cells. Methods A panel of human glioblastoma cultures, grown as stem cells (neurospheres) and adherent cells, was used. Results Neurospheres had a multidrug resistant phenotype compared with adherent cells. Such chemoresistance was overcome by apparently noncytotoxic doses of temozolomide, which chemosensitized glioblastoma cells to doxorubicin, vinblastine, and etoposide. This effect was selective for P-glycoprotein (Pgp) substrates and for stem cells, leading to an investigation of whether there was a correlation between the expression of Pgp and the activity of typical stemness pathways. We found that Wnt3a and ABCB1, which encodes for Pgp, were both highly expressed in glioblastoma stem cells and reduced by temozolomide. Temozolomide-treated cells had increased methylation of the cytosine–phosphate–guanine islands in the Wnt3a gene promoter, decreased expression of Wnt3a, disrupted glycogen synthase-3 kinase/β-catenin axis, reduced transcriptional activation of ABCB1, and a lower amount and activity of Pgp. Wnt3a overexpression was sufficient to transform adherent cells into neurospheres and to simultaneously increase proliferation and ABCB1 expression. On the contrary, glioblastoma stem cells silenced for Wnt3a lost the ability to form neurospheres and reduced at the same time the proliferation rate and ABCB1 levels. Conclusions Our work suggests that Wnt3a is an autocrine mediator of stemness, proliferation, and chemoresistance in human glioblastoma and that temozolomide may chemosensitize the stem cell population by downregulating Wnt3a signaling. PMID:23897632

Stem Cell Therapies for Knee Cartilage Repair: The Current Status of Preclinical and Clinical Studies

PubMed Central

Anderson, John A.; Little, Dianne; Toth, Alison P.; Moorman, Claude T.; Tucker, Bradford S.; Ciccotti, Michael G.; Guilak, Farshid

2014-01-01

Background Articular cartilage damage of the knee is common, causing significant morbidity worldwide. Many adult tissues contain cells that are able to differentiate into multiple cell types, including chondrocytes. These stem cells have gained significant attention over the past decade and may become frontline management for cartilage defects in the very near future. Purpose The role of stem cells in the treatment of knee osteochondral defects was reviewed. Recent animal and clinical studies were reviewed to determine the benefits and potential outcomes of using stem cells for cartilage defects. Study Design Literature review. Methods A PubMed search was undertaken. The key phrase “stem cells and knee” was used. The search included reviews and original articles over an unlimited time period. From this search, articles outlining animal and clinical trials were selected. A search of current clinical trials in progress was performed on the clinicaltrials.gov website, and “stem cells and knee” was used as the search phrase. Results Stem cells have been used in many recent in vitro and animal studies. A number of cell-based approaches for cartilage repair have progressed from preclinical animal studies into clinical trials. Conclusion The use of stem cells for the treatment of cartilage defects is increasing in animal and clinical studies. Methods of delivery of stem cells to the knee’s cartilage vary from direct injection to implantation with scaffolds. While these approaches are highly promising, there is currently limited evidence of a direct clinical benefit, and further research is required to assess the overall outcome of stem cell therapies for knee cartilage repair. PMID:24220016

Neural Stem Cells Derived Directly from Adipose Tissue.

PubMed

Petersen, Eric D; Zenchak, Jessica R; Lossia, Olivia V; Hochgeschwender, Ute

2018-05-01

Neural stem cells (NSCs) are characterized as self-renewing cell populations with the ability to differentiate into the multiple tissue types of the central nervous system. These cells can differentiate into mature neurons, astrocytes, and oligodendrocytes. This category of stem cells has been shown to be a promisingly effective treatment for neurodegenerative diseases and neuronal injury. Most treatment studies with NSCs in animal models use embryonic brain-derived NSCs. This approach presents both ethical and feasibility issues for translation to human patients. Adult tissue is a more practical source of stem cells for transplantation therapies in humans. Some adult tissues such as adipose tissue and bone marrow contain a wide variety of stem cell populations, some of which have been shown to be similar to embryonic stem cells, possessing many pluripotent properties. Of these stem cell populations, some are able to respond to neuronal growth factors and can be expanded in vitro, forming neurospheres analogous to cells harvested from embryonic brain tissue. In this study, we describe a method for the collection and culture of cells from adipose tissue that directly, without going through intermediates such as mesenchymal stem cells, results in a population of NSCs that are able to be expanded in vitro and be differentiated into functional neuronal cells. These adipose-derived NSCs display a similar phenotype to those directly derived from embryonic brain. When differentiated into neurons, cells derived from adipose tissue have spontaneous spiking activity with network characteristics similar to that of neuronal cultures.

Clonal analysis of lineage fate in native haematopoiesis.

PubMed

Rodriguez-Fraticelli, Alejo E; Wolock, Samuel L; Weinreb, Caleb S; Panero, Riccardo; Patel, Sachin H; Jankovic, Maja; Sun, Jianlong; Calogero, Raffaele A; Klein, Allon M; Camargo, Fernando D

2018-01-11

Haematopoiesis, the process of mature blood and immune cell production, is functionally organized as a hierarchy, with self-renewing haematopoietic stem cells and multipotent progenitor cells sitting at the very top. Multiple models have been proposed as to what the earliest lineage choices are in these primitive haematopoietic compartments, the cellular intermediates, and the resulting lineage trees that emerge from them. Given that the bulk of studies addressing lineage outcomes have been performed in the context of haematopoietic transplantation, current models of lineage branching are more likely to represent roadmaps of lineage potential than native fate. Here we use transposon tagging to clonally trace the fates of progenitors and stem cells in unperturbed haematopoiesis. Our results describe a distinct clonal roadmap in which the megakaryocyte lineage arises largely independently of other haematopoietic fates. Our data, combined with single-cell RNA sequencing, identify a functional hierarchy of unilineage- and oligolineage-producing clones within the multipotent progenitor population. Finally, our results demonstrate that traditionally defined long-term haematopoietic stem cells are a significant source of megakaryocyte-restricted progenitors, suggesting that the megakaryocyte lineage is the predominant native fate of long-term haematopoietic stem cells. Our study provides evidence for a substantially revised roadmap for unperturbed haematopoiesis, and highlights unique properties of multipotent progenitors and haematopoietic stem cells in situ.

miRNA-regulated cancer stem cells: understanding the property and the role of miRNA in carcinogenesis.

PubMed

Chakraborty, Chiranjib; Chin, Kok-Yong; Das, Srijit

2016-10-01

Over the last few years, microRNAs (miRNA)-controlled cancer stem cells have drawn enormous attention. Cancer stem cells are a small population of tumor cells that possess the stem cell property of self-renewal. Recent data shows that miRNA regulates this small population of stem cells. In the present review, we explained different characteristics of cancer stem cells as well as miRNA regulation of self-renewal and differentiation in cancer stem cells. We also described the migration and tumor formation. Finally, we described the different miRNAs that regulate various types of cancer stem cells, such as prostate cancer stem cells, head and neck cancer stem cells, breast cancer stem cells, colorectal cancer stem cells, lung cancer stem cells, gastric cancer stem cells, pancreatic cancer stem cells, etc. Extensive research is needed in order to employ miRNA-based therapeutics to control cancer stem cell population in various cancers in the future.

Role of geometrical cues in bone marrow-derived mesenchymal stem cell survival, growth and osteogenic differentiation.

PubMed

Gupta, Dhanak; Grant, David M; Zakir Hossain, Kazi M; Ahmed, Ifty; Sottile, Virginie

2018-02-01

Mesenchymal stem cells play a vital role in bone formation process by differentiating into osteoblasts, in a tissue that offers not a flat but a discontinuous three-dimensional (3D) topography in vivo. In order to understand how geometry may be affecting mesenchymal stem cells, this study explored the influence of 3D geometry on mesenchymal stem cell-fate by comparing cell growth, viability and osteogenic potential using monolayer (two-dimensional, 2D) with microsphere (3D) culture systems normalised to surface area. The results suggested lower cell viability and reduced cell growth in 3D. Alkaline phosphatase activity was higher in 3D; however, both collagen and mineral deposition appeared significantly lower in 3D, even after osteogenic supplementation. Also, there were signs of patchy mineralisation in 3D with or without osteogenic supplementation as early as day 7. These results suggest that the convex surfaces on microspheres and inter-particulate porosity may have led to variable cell morphology and fate within the 3D culture. This study provides deeper insights into geometrical regulation of mesenchymal stem cell responses applicable for bone tissue engineering.

Melatonin promotes goat spermatogonia stem cells (SSCs) proliferation by stimulating glial cell line-derived neurotrophic factor (GDNF) production in Sertoli cells.

PubMed

Niu, Bowen; Li, Bo; Wu, Chongyang; Wu, Jiang; Yan, Yuan; Shang, Rui; Bai, Chunling; Li, Guangpeng; Hua, Jinlian

2016-11-22

Melatonin has been reported to be an important endogenous hormone for regulating neurogenesis, immunityand the biological clock. Recently, the effects of melatonin on neural stem cells (NSCs), mesenchymal stem cells(MSCs), and induced pluripotent stem cells(iPSCs) have been reported; however, the effects of melatonin on spermatogonia stem cells (SSCs) are not clear. Here, 1μM and 1nM melatonin was added to medium when goat SSCs were cultured in vitro, the results showed that melatonin could increase the formation and size of SSC colonies. Real-time quantitative PCR (QRT-PCR) and western blot analysis showed that the expression levels of SSC proliferation and self-renewal markers were up-regulated. Meanwhile, QRT-PCR results showed that melatonin inhibit the mRNA expression level of SSC differentiation markers. ELISA analysis showed an obvious increase in the concentration of GDNF (a niche factor secreted by Sertoli cells) in the medium when treated with melatonin. Meanwhile, the phosphorylation level of AKT, a downstream of GDNF-GFRa1-RET pathway was activated. In conclusion, melatonin promotes goat SSC proliferation by stimulating GDNF production in Sertoli cells.

On the Stem Cell Origin of Cancer

PubMed Central

Sell, Stewart

2010-01-01

In each major theory of the origin of cancer—field theory, chemical carcinogenesis, infection, mutation, or epigenetic change—the tissue stem cell is involved in the generation of cancer. Although the cancer type is identified by the more highly differentiated cells in the cancer cell lineage or hierarchy (transit-amplifying cells), the property of malignancy and the molecular lesion of the cancer exist in the cancer stem cell. In the case of teratocarcinomas, normal germinal stem cells have the potential to become cancers if placed in an environment that allows expression of the cancer phenotype (field theory). In cancers due to chemically induced mutations, viral infections, somatic and inherited mutations, or epigenetic changes, the molecular lesion or infection usually first occurs in the tissue stem cells. Cancer stem cells then give rise to transit-amplifying cells and terminally differentiated cells, similar to what happens in normal tissue renewal. However, the major difference between cancer growth and normal tissue renewal is that whereas normal transit amplifying cells usually differentiate and die, at various levels of differentiation, the cancer transit-amplifying cells fail to differentiate normally and instead accumulate (ie, they undergo maturation arrest), resulting in cancer growth. PMID:20431026

Hopes and fears for professional movement in the stem cell community.

PubMed

Longstaff, Holly; Khramova, Vera; Eijkholt, Marleen; Mizgalewicz, Ania; Illes, Judy

2013-05-02

We examine here how the issue of professional migration in stem cell research has been explored in news media, government documents, and the peer-reviewed literature. The results shed light on how patterns of and forces that motivate these movements are depicted and highlight issues of significance to the stem cell community. Copyright © 2013 Elsevier Inc. All rights reserved.

Integrative Technologies and Knowledge Gatekeepers: Bridging the Gap between Epistemic Communities in the Case of Stem Cell Science

ERIC Educational Resources Information Center

Wink, Rudiger

2008-01-01

The article analyses the role of gatekeepers between regional and disciplinary innovation systems in stem cell research as a case of integrative technologies. Which kind of gatekeepers is needed and which function can be fulfilled, differs along the knowledge value chain. Empirical results are used to explain the rationality of stem cell policies…

The novel tumour suppressor Madm regulates stem cell competition in the Drosophila testis

PubMed Central

Singh, Shree Ram; Liu, Ying; Zhao, Jiangsha; Zeng, Xiankun; Hou, Steven X.

2016-01-01

Stem cell competition has emerged as a mechanism for selecting fit stem cells/progenitors and controlling tumourigenesis. However, little is known about the underlying molecular mechanism. Here we identify Mlf1-adaptor molecule (Madm), a novel tumour suppressor that regulates the competition between germline stem cells (GSCs) and somatic cyst stem cells (CySCs) for niche occupancy. Madm knockdown results in overexpression of the EGF receptor ligand vein (vn), which further activates EGF receptor signalling and integrin expression non-cell autonomously in CySCs to promote their overproliferation and ability to outcompete GSCs for niche occupancy. Conversely, expressing a constitutively activated form of the Drosophila JAK kinase (hopTum−l) promotes Madm nuclear translocation, and suppresses vn and integrin expression in CySCs that allows GSCs to outcompete CySCs for niche occupancy and promotes GSC tumour formation. Tumour suppressor-mediated stem cell competition presented here could be a mechanism of tumour initiation in mammals. PMID:26792023

The novel tumour suppressor Madm regulates stem cell competition in the Drosophila testis.

PubMed

Singh, Shree Ram; Liu, Ying; Zhao, Jiangsha; Zeng, Xiankun; Hou, Steven X

2016-01-21

Stem cell competition has emerged as a mechanism for selecting fit stem cells/progenitors and controlling tumourigenesis. However, little is known about the underlying molecular mechanism. Here we identify Mlf1-adaptor molecule (Madm), a novel tumour suppressor that regulates the competition between germline stem cells (GSCs) and somatic cyst stem cells (CySCs) for niche occupancy. Madm knockdown results in overexpression of the EGF receptor ligand vein (vn), which further activates EGF receptor signalling and integrin expression non-cell autonomously in CySCs to promote their overproliferation and ability to outcompete GSCs for niche occupancy. Conversely, expressing a constitutively activated form of the Drosophila JAK kinase (hop(Tum-l)) promotes Madm nuclear translocation, and suppresses vn and integrin expression in CySCs that allows GSCs to outcompete CySCs for niche occupancy and promotes GSC tumour formation. Tumour suppressor-mediated stem cell competition presented here could be a mechanism of tumour initiation in mammals.

What is a stem cell?

PubMed

Slack, Jonathan M W

2018-05-15

The historical roots of the stem cell concept are traced with respect to its usage in embryology and in hematology. The modern consensus definition of stem cells, comprising both pluripotent stem cells in culture and tissue-specific stem cells in vivo, is explained and explored. Methods for identifying stem cells are discussed with respect to cell surface markers, telomerase, label retention and transplantability, and properties of the stem cell niche are explored. The CreER method for identifying stem cells in vivo is explained, as is evidence in favor of a stochastic rather than an obligate asymmetric form of cell division. In conclusion, it is found that stem cells do not possess any unique and specific molecular markers; and stem cell behavior depends on the environment of the cell as well as the stem cell's intrinsic qualities. Furthermore, the stochastic mode of division implies that stem cell behavior is a property of a cell population not of an individual cell. In this sense, stem cells do not exist in isolation but only as a part of multicellular system. This article is categorized under: Adult Stem Cells, Tissue Renewal, and Regeneration > Tissue Stem Cells and Niches Adult Stem Cells, Tissue Renewal, and Regeneration > Methods and Principles Adult Stem Cells, Tissue Renewal, and Regeneration > Environmental Control of Stem Cells. © 2018 Wiley Periodicals, Inc.

Preclinical Assessment of the Proliferation Capacity of Gingival and Periodontal Ligament Stem Cells from Diabetic Patients.

PubMed

Assem, Mostafa; Kamal, Samia; Sabry, Dina; Soliman, Nadia; Aly, Riham M

2018-02-15

Stem cells have recently received great interest as potential therapeutics alternative for a variety of diseases. The oral and maxillofacial region, in particular, encompasses a variety of distinctive mesenchymal (MSC) populations and is characterized by a potent multilineage differentiation capacity. In this report, we aimed to investigate the effect of diabetes on the proliferation potential of stem cells isolated from controlled diabetic patients (type 2) and healthy individuals. The proliferation rate of gingival and periodontal derived stem cells isolated from diabetic & healthy individuals were compared using MTT Assay. Expression levels of Survivin in isolated stem cells from all groups were measured by qRt - PCR. There was a significantly positive correlation between proliferation rate and expression of Survivin in all groups which sheds light on the importance of Survivin as a reliable indicator of proliferation. The expression of Survivin further confirmed the proliferation results from MTT Assay where the expression of stem cells from non - diabetic individuals was higher than diabetic patients. Taking together all the results, it could be concluded that PDLSC and GSC are promising candidates for autologous regenerative therapy due to their ease of accessibility in addition to their high proliferative rates.

Diabetes-Induced Dysfunction of Mitochondria and Stem Cells in Skeletal Muscle and the Nervous System

PubMed Central

Fujimaki, Shin; Kuwabara, Tomoko

2017-01-01

Diabetes mellitus is one of the most common metabolic diseases spread all over the world, which results in hyperglycemia caused by the breakdown of insulin secretion or insulin action or both. Diabetes has been reported to disrupt the functions and dynamics of mitochondria, which play a fundamental role in regulating metabolic pathways and are crucial to maintain appropriate energy balance. Similar to mitochondria, the functions and the abilities of stem cells are attenuated under diabetic condition in several tissues. In recent years, several studies have suggested that the regulation of mitochondria functions and dynamics is critical for the precise differentiation of stem cells. Importantly, physical exercise is very useful for preventing the diabetic alteration by improving the functions of both mitochondria and stem cells. In the present review, we provide an overview of the diabetic alterations of mitochondria and stem cells and the preventive effects of physical exercise on diabetes, focused on skeletal muscle and the nervous system. We propose physical exercise as a countermeasure for the dysfunction of mitochondria and stem cells in several target tissues under diabetes complication and to improve the physiological function of patients with diabetes, resulting in their quality of life being maintained. PMID:29036909

Diabetes-Induced Dysfunction of Mitochondria and Stem Cells in Skeletal Muscle and the Nervous System.

PubMed

Fujimaki, Shin; Kuwabara, Tomoko

2017-10-14

Diabetes mellitus is one of the most common metabolic diseases spread all over the world, which results in hyperglycemia caused by the breakdown of insulin secretion or insulin action or both. Diabetes has been reported to disrupt the functions and dynamics of mitochondria, which play a fundamental role in regulating metabolic pathways and are crucial to maintain appropriate energy balance. Similar to mitochondria, the functions and the abilities of stem cells are attenuated under diabetic condition in several tissues. In recent years, several studies have suggested that the regulation of mitochondria functions and dynamics is critical for the precise differentiation of stem cells. Importantly, physical exercise is very useful for preventing the diabetic alteration by improving the functions of both mitochondria and stem cells. In the present review, we provide an overview of the diabetic alterations of mitochondria and stem cells and the preventive effects of physical exercise on diabetes, focused on skeletal muscle and the nervous system. We propose physical exercise as a countermeasure for the dysfunction of mitochondria and stem cells in several target tissues under diabetes complication and to improve the physiological function of patients with diabetes, resulting in their quality of life being maintained.

Dormancy activation mechanism of oral cavity cancer stem cells.

PubMed

Chen, Xiang; Li, Xin; Zhao, Baohong; Shang, Dehao; Zhong, Ming; Deng, Chunfu; Jia, Xinshan

2015-07-01

Radiotherapy and chemotherapy are targeted primarily at rapidly proliferating cancer cells and are unable to eliminate cancer stem cells in the G0 phase. Thus, these treatments cannot prevent the recurrence and metastasis of cancer. Understanding the mechanisms by which cancer stem cells are maintained in the dormant G0 phase, and how they become active is key to developing new cancer therapies. The current study found that the anti-cancer drug 5-fluorouracil, acting on the oral squamous cell carcinoma KB cell line, selectively killed proliferating cells while sparing cells in the G0 phase. Bisulfite sequencing PCR showed that demethylation of the Sox2 promoter led to the expression of Sox2. This then resulted in the transformation of cancer stem cells from the G0 phase to the division stage and suggested that the transformation of cancer stem cells from the G0 phase to the division stage is closely related to an epigenetic modification of the cell.

NANOG priming before full reprogramming may generate germ cell tumours.

PubMed

Grad, I; Hibaoui, Y; Jaconi, M; Chicha, L; Bergström-Tengzelius, R; Sailani, M R; Pelte, M F; Dahoun, S; Mitsiadis, T A; Töhönen, V; Bouillaguet, S; Antonarakis, S E; Kere, J; Zucchelli, M; Hovatta, O; Feki, A

2011-11-09

Reprogramming somatic cells into a pluripotent state brings patient-tailored, ethical controversy-free cellular therapy closer to reality. However, stem cells and cancer cells share many common characteristics; therefore, it is crucial to be able to discriminate between them. We generated two induced pluripotent stem cell (iPSC) lines, with NANOG pre-transduction followed by OCT3/4, SOX2, and LIN28 overexpression. One of the cell lines, CHiPS W, showed normal pluripotent stem cell characteristics, while the other, CHiPS A, though expressing pluripotency markers, failed to differentiate and gave rise to germ cell-like tumours in vivo. Comparative genomic hybridisation analysis of the generated iPS lines revealed that they were genetically more stable than human embryonic stem cell counterparts. This analysis proved to be predictive for the differentiation potential of analysed cells. Moreover, the CHiPS A line expressed a lower ratio of p53/p21 when compared to CHiPS W. NANOG pre-induction followed by OCT3/4, SOX2, MYC, and KLF4 induction resulted in the same tumour-inducing phenotype. These results underline the importance of a re-examination of the role of NANOG during reprogramming. Moreover, this reprogramming method may provide insights into primordial cell tumour formation and cancer stem cell transformation.

Evidence for circulating cancer stem-like cells and epithelial-mesenchymal transition phenotype in the pleurospheres derived from lung adenocarcinoma using liquid biopsy.

PubMed

Mirza, Sheefa; Jain, Nayan; Rawal, Rakesh

2017-03-01

Lung cancer stem cells are supposed to be the main drivers of tumor initiation, maintenance, drug resistance, and relapse of the disease. Hence, identification of the cellular and molecular aspects of these cells is a prerequisite for targeted therapy of lung cancer. Currently, analysis of circulating tumor cells has the potential to become the main diagnostic technique to monitor disease progression or therapeutic response as it is non-invasive. However, accurate detection of circulating tumor cells has remained a challenge, as epithelial cell markers used so far are not always trustworthy for detecting circulating tumor cells, especially during epithelial-mesenchymal transition. As cancer stem cells are the only culprit to initiate metastatic tumors, our aim was to isolate and characterize circulating tumor stem cells rather than circulating tumor cells from the peripheral blood of NSCLC adenocarcinoma as limited data are available addressing the gene expression profiling of lung cancer stem cells. Here, we reveal that CD44(+)/CD24(-) population in circulation not only exhibit stem cell-related genes but also possess epithelial-mesenchymal transition characteristics. In conclusion, the use of one or more cancer stem cell markers along with epithelial, mesenchymal and epithelial mesenchymal transition markers will prospectively provide the most precise assessment of the threat for recurrence and metastatic disease and has a great potential for forthcoming applications in harvesting circulating tumor stem cells and their downstream applications. Our results will aid in developing diagnostic and prognostic modalities and personalized treatment regimens like dendritic cell-based immunotherapy that can be utilized for targeting and eliminating circulating tumor stem cells, to significantly reduce the possibility of relapse and improve clinical outcomes.

Near-field photothermal microspectroscopy for adult stem-cell identification and characterization.

PubMed

Grude, Olaug; Hammiche, Azzedine; Pollock, Hubert; Bentley, Adam J; Walsh, Michael J; Martin, Francis L; Fullwood, Nigel J

2007-12-01

The identification of stem cells in adult tissue is a challenging problem in biomedicine. Currently, stem cells are identified by individual epitopes, which are generally tissue specific. The discovery of a stem-cell marker common to other adult tissue types could open avenues in the development of therapeutic stem-cell strategies. We report the use of the novel technique of Fourier transform infrared near-field photothermal microspectroscopy (FTIR-PTMS) for the characterization of stem cells, transit amplifying (TA) cells and terminally differentiated (TD) cells in the corneal epithelium. Principal component analysis (PCA) data demonstrate excellent discrimination of cell type by spectra. PCA in combination with linear discriminant analysis (PCA-LDA) shows that FTIR-PTMS very effectively discriminates between the three cell populations. Statistically significant differences above the 99% confidence level between IR spectra from stem cells and TA cells suggest that nucleic acid conformational changes are an important component of the differences between spectral data from the two cell types. FTIR-PTMS is a new addition to existing spectroscopy methods based on the concept of interfacing a conventional FTIR spectrometer with an atomic force microscope equipped with a near-field thermal sensing probe. FTIR-PTMS spectroscopy currently has spatial resolution that is similar to that of diffraction-limited optical detection FTIR spectroscopy techniques, but as a near-field probing technique has considerable potential for further improvement. Our work also suggests that FTIR-PTMS is potentially more sensitive than synchrotron radiation FTIR spectroscopy for some applications. Microspectroscopy techniques like FTIR-PTMS provide information about the entire molecular composition of cells, in contrast to epitope recognition that only considers the presence or absence of individual molecules. Our results with FTIR-PTMS on corneal stem cells are promising for the potential development of an IR spectral fingerprint for stem cells.

Slow and sustained nitric oxide releasing compounds inhibit multipotent vascular stem cell proliferation and differentiation without causing cell death

DOE Office of Scientific and Technical Information (OSTI.GOV)

Curtis, Brandon M.; Leix, Kyle Alexander; Ji, Yajing

Highlights: • Multipotent vascular stem cells (MVSCs) proliferate and differentiate. • Nitric oxide inhibits proliferation of MVSCs. • Nitric oxide inhibits MVSC differentiation to mesenchymal-like stem cells (MSCs). • Smooth muscle cells (SMCs) neither de-differentiate nor proliferate. - Abstract: Atherosclerosis is the leading cause of cerebral and myocardial infarction. It is believed that neointimal growth common in the later stages of atherosclerosis is a result of vascular smooth muscle cell (SMC) de-differentiation in response to endothelial injury. However, the claims of the SMC de-differentiation theory have not been substantiated by monitoring the fate of mature SMCs in response to suchmore » injuries. A recent study suggests that atherosclerosis is a consequence of multipotent vascular stem cell (MVSC) differentiation. Nitric oxide (NO) is a well-known mediator against atherosclerosis, in part because of its inhibitory effect on SMC proliferation. Using three different NO-donors, we have investigated the effects of NO on MVSC proliferation. Results indicate that NO inhibits MVSC proliferation in a concentration dependent manner. A slow and sustained delivery of NO proved to inhibit proliferation without causing cell death. On the other hand, larger, single-burst NO concentrations, inhibits proliferation, with concurrent significant cell death. Furthermore, our results indicate that endogenously produced NO inhibits MVSC differentiation to mesenchymal-like stem cells (MSCs) and subsequently to SMC as well.« less

Cell surface glycan engineering of neural stem cells augments neurotropism and improves recovery in a murine model of multiple sclerosis

PubMed Central

Merzaban, Jasmeen S; Imitola, Jaime; Starossom, Sarah C; Zhu, Bing; Wang, Yue; Lee, Jack; Ali, Amal J; Olah, Marta; Abuelela, Ayman F; Khoury, Samia J; Sackstein, Robert

2015-01-01

Neural stem cell (NSC)-based therapies offer potential for neural repair in central nervous system (CNS) inflammatory and degenerative disorders. Typically, these conditions present with multifocal CNS lesions making it impractical to inject NSCs locally, thus mandating optimization of vascular delivery of the cells to involved sites. Here, we analyzed NSCs for expression of molecular effectors of cell migration and found that these cells are natively devoid of E-selectin ligands. Using glycosyltransferase-programmed stereosubstitution (GPS), we glycan engineered the cell surface of NSCs (“GPS-NSCs”) with resultant enforced expression of the potent E-selectin ligand HCELL (hematopoietic cell E-/L-selectin ligand) and of an E-selectin-binding glycoform of neural cell adhesion molecule (“NCAM-E”). Following intravenous (i.v.) injection, short-term homing studies demonstrated that, compared with buffer-treated (control) NSCs, GPS-NSCs showed greater neurotropism. Administration of GPS-NSC significantly attenuated the clinical course of experimental autoimmune encephalomyelitis (EAE), with markedly decreased inflammation and improved oligodendroglial and axonal integrity, but without evidence of long-term stem cell engraftment. Notably, this effect of NSC is not a universal property of adult stem cells, as administration of GPS-engineered mouse hematopoietic stem/progenitor cells did not improve EAE clinical course. These findings highlight the utility of cell surface glycan engineering to boost stem cell delivery in neuroinflammatory conditions and indicate that, despite the use of a neural tissue-specific progenitor cell population, neural repair in EAE results from endogenous repair and not from direct, NSC-derived cell replacement. PMID:26153105

Human induced pluripotent stem cell differentiation and direct transdifferentiation into corneal epithelial-like cells

PubMed Central

Cieślar-Pobuda, Artur; Rafat, Mehrdad; Knoflach, Viktoria; Skonieczna, Magdalena; Hudecki, Andrzej; Małecki, Andrzej; Urasińska, Elżbieta; Ghavami, Seaid; Łos, Marek J.

2016-01-01

The corneal epithelium is maintained by a small pool of tissue stem cells located at the limbus. Through certain injuries or diseases this pool of stem cells may get depleted. This leads to visual impairment. Standard treatment options include autologous or allogeneic limbal stem cell (LSC) transplantation, however graft rejection and chronic inflammation lowers the success rate over long time. Induced pluripotent stem (iPS) cells have opened new possibilities for treating various diseases with patient specific cells, eliminating the risk of immune rejection. In recent years, several protocols have been developed, aimed at the differentiation of iPS cells into the corneal epithelial lineage by mimicking the environmental niche of limbal stem cells. However, the risk of teratoma formation associated with the use of iPS cells hinders most applications from lab into clinics. Here we show that the differentiation of iPS cells into corneal epithelial cells results in the expression of corneal epithelial markers showing a successful differentiation, but the process is long and the level of gene expression for the pluripotency markers does not vanish completely. Therefore we set out to determine a direct transdifferentiation approach to circumvent the intermediate state of pluripotency (iPS-stage). The resulting cells, obtained by direct transdifferentiation of fibroblasts into limbal cells, exhibited corneal epithelial cell morphology and expressed corneal epithelial markers. Hence we shows for the first time a direct transdifferentiation of human dermal fibroblasts into the corneal epithelial lineage that may serve as source for corneal epithelial cells for transplantation approaches. PMID:27275539

Feeder-cell-independent culture of the pig-embryonic-stem-cell-derived exocrine pancreatic cell line, PICM-31

USDA-ARS?s Scientific Manuscript database

The adaptation to feeder-independent growth of a pig embryonic stem cell-derived pancreatic cell line is described. The parental PICM-31 cell line, previously characterized as an exocrine pancreas cell line, was colony-cloned two times in succession resulting in the subclonal cell line, PICM-31A1. P...

The intersection of cancer, cancer stem cells, and the immune system: therapeutic opportunities.

PubMed

Silver, Daniel J; Sinyuk, Maksim; Vogelbaum, Michael A; Ahluwalia, Manmeet S; Lathia, Justin D

2016-02-01

During brain neoplasia, malignant cells subjugate the immune system to provide an environment that favors tumor growth. These mechanisms capitalize on tumor-promoting functions of various immune cell types and typically result in suppression of tumor immune rejection. Immunotherapy efforts are underway to disrupt these mechanisms and turn the immune system against developing tumors. While many of these therapies are already in early-stage clinical trials, understanding how these therapies impact various tumor cell populations, including self-renewing cancer stem cells, may help to predict their efficacy and clarify their mechanisms of action. Moreover, interrogating the biology of glioma cell, cancer stem cell, and immune cell interactions may provide additional therapeutic targets to leverage against disease progression. In this review, we begin by highlighting a series of investigations into immune cell-mediated tumor promotion that do not parse the tumor into stem and non-stem components. We then take a closer look at the immune-suppressive mechanisms derived specifically from cancer stem cell interactions with the immune system and end with an update on immunotherapy and cancer stem cell-directed clinical trials in glioblastoma. © The Author(s) 2015. Published by Oxford University Press on behalf of the Society for Neuro-Oncology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Comparison of differentiation potential of male mouse adipose tissue and bone marrow derived-mesenchymal stem cells into germ cells

PubMed Central

Hosseinzadeh Shirzeily, Maryam; Pasbakhsh, Parichehr; Amidi, Fardin; Mehrannia, Kobra; Sobhani, Aligholi

2013-01-01

Background: Recent publications about differentiation of stem cells to germ cells have motivated researchers to make new approaches to infertility. In vitro production of germ cells improves understanding differentiation process of male and female germ cells. Due to the problem of using embryonic stem cells (ESC), it’s necessary the mentioned cells be replaced with some adult multi-potent stem cells in laboratories. Objective: The aim of this study was to obtain germ cells from appropriate source beyond ESC and compare differential potentials of adipocytes derived stem cells (ADMSCs) with bone marrow derived stem cells (BMMSCs). Materials and Methods: To find multi-potential entity, after providing purified ADMSCs and BMMSCs, differentiation to osteoblast and adipocyte was confirmed by using appropriate culture medium. To confirm mesenchymal lineage production superficial markers (expression of CD90 and CD44 and non-expression of CD45 and CD31) were investigated by flowcytometry. Then the cells were differentiated to germ cells in inductive medium containing retinoic acid for 7days. To evaluate germ cells characteristic markers [Dazl (Deleted in azoospermia-like), Mvh (Mouse vasa homolog gene), Stra8 (Stimulated by retinoic acid) and Scp3 (Synaptonemal complex protein 3)] flowcytometry, imunoflorescence and real time PCR were used. Results: Both types of cells were able to differentiate into osteoblast and adipocyte cells and presentation of stem cell superficial markers (CD90, CD44) and absence of endothelial and blood cell markers (CD31, CD45) were confirmative The flowcytometry, imunoflorescence and real time PCR results showed remarkable expression of germ cells characteristic markers (Mvh, Dazl, Stra8, and Scp3). Conclusion: It was found that although ADMSCs were attained easier and also cultured and differentiated rapidly, germ cell markers were expressed in BMMSCs significantly more than ADMSCs. This article extracted from M.Sc. thesis. (Maryam Hosseinzadeh Shirzeily) PMID:24639722

Cancer stem cells: A product of clonal evolution?

PubMed

van Niekerk, Gustav; Davids, Lester M; Hattingh, Suzèl M; Engelbrecht, Anna-Mart

2017-03-01

The cancer stem cell (CSC) model has emerged as a prominent paradigm for explaining tumour heterogeneity. CSCs in tumour recurrence and drug resistance have also been implicated in a number of studies. In fact, CSCs are often identified by their expression of drug-efflux proteins which are also highly expressed in normal stem cells. Similarly, pro-survival or proliferation signalling often exhibited by stem cells is regularly reported as being upregulated by CSC. Here we review evidence suggesting that many aspects of CSCs are more readily described by clonal evolution. As an example, cancer cells often exhibit copy number gains of genes involved in drug-efflux proteins and pro-survival signalling. Consequently, clonal selection for stem cell traits may result in cancer cells developing "stemness" traits which impart a fitness advantage, without strictly following a CSC model. Finally, since symmetric cell division would give rise to more cells than asymmetric division, it is expected that more advanced tumours would depart from a CSC. Collectively, these observations suggest clonal evolution may explain many aspects of the CSC. © 2016 UICC.

miR-335 negatively regulates osteosarcoma stem cell-like properties by targeting POU5F1.

PubMed

Guo, Xiaodong; Yu, Ling; Zhang, Zhengpei; Dai, Guo; Gao, Tian; Guo, Weichun

2017-01-01

Evidence is accumulating to link cancer stem cells to the pathogenesis and progression of osteosarcoma. The aim of this study is to investigate the role of miR-335 in osteosarcoma stem cells. Tumor spheroid culture and flow cytometry were applied to screen out osteosarcoma stem cells. Real-time quantitative PCR was used to detect the expression level of miR-335 in MG63, U2OS and 143B osteosarcoma stem cells. The relationship of miR-335 expression with osteosarcoma stem cells was then analyzed. Transwell assay and transplantation assay were performed to elucidate biological effects of miR-335 on cell invasion and vivo tumor formation. Western Blot and luciferase assays were executed to investigate the regulation of POU5F1 by miR-335. The expression of miR-335 in osteosarcoma stem cells was lower than their differentiated counterparts. Cells expressing miR-335 possessed decreased stem cell-like properties. Gain or loss of function assays were applied to find that miR-335 antagonist promoted stem cell-like properties as well as invasion. Luciferase report and transfection assay showed that POU5F1 was downregulated by miR-335. Pre-miR-335 resulted in tumor enhanced sensitivity to traditional chemotherapy, whereas anti-miR-335 promoted chemoresistance. Finally, the inhibitory effect of miR-335 on in vivo tumor formation showed that combination of pre-miR-335 with cisplatin further reduced the tumor size, and miR-335 brought down the sphere formation capacity induced by cisplatin. The current study demonstrates that miR-335 negatively regulates osteosarcoma stem cell-like properties by targeting POU5F1, and miR-335 could target CSCs to synergize with traditional chemotherapeutic agents to overcome osteosarcoma.

Mechanical stimulation of cyclic tensile strain induces reduction of pluripotent related gene expressions via activation of Rho/ROCK and subsequent decreasing of AKT phosphorylation in human induced pluripotent stem cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Teramura, Takeshi, E-mail: teramura@med.kindai.ac.jp; Takehara, Toshiyuki; Onodera, Yuta

2012-01-13

Highlights: Black-Right-Pointing-Pointer Mechanical stimulation is an important factor for regulation of stem cell fate. Black-Right-Pointing-Pointer Cyclic stretch to human induced pluripotent stem cells activated small GTPase Rho. Black-Right-Pointing-Pointer Rho-kinase activation attenuated pluripotency via inhibition of AKT activation. Black-Right-Pointing-Pointer This reaction could be reproduced only by transfection of dominant active Rho. Black-Right-Pointing-Pointer Rho/ROCK are important molecules in mechanotransduction and control of stemness. -- Abstract: Mechanical stimulation has been shown to regulate the proliferation and differentiation of stem cells. However, the effects of the mechanical stress on the stemness or related molecular mechanisms have not been well determined. Pluripotent stem cells suchmore » as embryonic stem (ES) cells and induced pluripotent stem (iPS) cells are used as good materials for cell transplantation therapy and research of mammalian development, since they can self-renew infinitely and differentiate into various cell lineages. Here we demonstrated that the mechanical stimulation to human iPS cells altered alignment of actin fibers and expressions of the pluripotent related genes Nanog, POU5f1 and Sox2. In the mechanically stimulated iPS cells, small GTPase Rho was activated and interestingly, AKT phosphorylation was decreased. Inhibition of Rho-associated kinase ROCK recovered the AKT phosphorylation and the gene expressions. These results clearly suggested that the Rho/ROCK is a potent primary effector of mechanical stress in the pluripotent stem cells and it participates to pluripotency-related signaling cascades as an upper stream regulator.« less

Therapeutic Effect of Human Adipose Tissue-Derived Mesenchymal Stem Cells in Experimental Corneal Failure Due to Limbal Stem Cell Niche Damage.

PubMed

Galindo, Sara; Herreras, José M; López-Paniagua, Marina; Rey, Esther; de la Mata, Ana; Plata-Cordero, María; Calonge, Margarita; Nieto-Miguel, Teresa

2017-10-01

Limbal stem cells are responsible for the continuous renewal of the corneal epithelium. The destruction or dysfunction of these stem cells or their niche induces limbal stem cell deficiency (LSCD) leading to visual loss, chronic pain, and inflammation of the ocular surface. To restore the ocular surface in cases of bilateral LSCD, an extraocular source of stem cells is needed to avoid dependence on allogeneic limbal stem cells that are difficult to obtain, isolate, and culture. The aim of this work was to test the tolerance and the efficacy of human adipose tissue-derived mesenchymal stem cells (hAT-MSCs) to regenerate the ocular surface in two experimental models of LSCD that closely resemble different severity grades of the human pathology. hAT-MSCs transplanted to the ocular surface of the partial and total LSCD models developed in rabbits were well tolerated, migrated to inflamed tissues, reduced inflammation, and restrained the evolution of corneal neovascularization and corneal opacity. The expression profile of the corneal epithelial cell markers CK3 and E-cadherin, and the limbal epithelial cell markers CK15 and p63 was lost in the LSCD models, but was partially recovered after hAT-MSC transplantation. For the first time, we demonstrated that hAT-MSCs improve corneal and limbal epithelial phenotypes in animal LSCD models. These results support the potential use of hAT-MSCs as a novel treatment of ocular surface failure due to LSCD. hAT-MSCs represent an available, non-immunogenic source of stem cells that may provide therapeutic benefits in addition to reduce health care expenses. Stem Cells 2017;35:2160-2174. © 2017 AlphaMed Press.

Stem cell tourism--a web-based analysis of clinical services available to international travellers.

PubMed

Connolly, Ruairi; O'Brien, Timothy; Flaherty, Gerard

2014-01-01

Stem cell therapies are advertised through online resources which describe a range of treatments with diverse clinical indications. Stem cell tourists may not be aware of the information they should seek when consulting these clinics, or of the potential risks involved. The aim of this study was to characterise the therapies offered by online stem cell clinics. A web based search utilising five search terms was employed. The first twenty pages of each search result were screened against 340 variables. 224 out of 1091 websites advertised stem cell clinics. 68 eligible sites covering 21 countries were evaluated. The top five clinical indications for stem cell therapy were multiple sclerosis, anti-ageing, Parkinson's disease, stroke and spinal cord injury. Adult, autologous stem cells were the most commonly utilised stem cell, and these were frequently sourced from bone marrow and adipose tissue and administered intravenously. Thirty-four per cent of sites mentioned the number of patients treated while one quarter of clinics provided outcome data. Twenty-nine per cent of clinics had an internationally recognised accreditation. Fifteen per cent of clinics stated that their therapies posed no risk. Eighty-eight per cent of clinics claimed treatment effectiveness, with 16% describing their curative potential. Over 40% of sites did not specify the number or duration of treatments. Fifty-three per cent of clinics requested access to patients' medical records, and 12% recommended patients discuss the proposed therapy with their doctor. No clinic recommended that travellers consult a travel medicine specialist or receive vaccinations prior to their intended travel. One quarter of sites discussed contraindications to treatment, with 41% of sites detailing follow up patient care. There is potential for stem cell tourists to receive misleading or deficient information from online stem cell clinics. Both the stem cell tourist and travel medicine practitioner should be educated on the potential risks associated with stem cell clinical services advertised online.

Quercetin potentiates transdifferentiation of bone marrow mesenchymal stem cells into the beta cells in vitro.

PubMed

Miladpour, B; Rasti, M; Owji, A A; Mostafavipour, Z; Khoshdel, Z; Noorafshan, A; Zal, F

2017-05-01

Type 1 diabetes is an autoimmune disease caused by the destruction of β-cells in the pancreas. Bone marrow mesenchymal stem cells are multipotent and easy accessible adult stem cells that may provide options in the treatment of type 1 diabetes. Injured pancreatic extract can promote the differentiation of rat bone marrow mesenchymal stem cells into β-cells. We aimed to observe the effect of quercetin in differentiation and insulin secretion in β-cells. Bone marrow mesenchymal stem cells were obtained from the tibiae of rats. Cell surface markers were analyzed by flow cytometry. The cells were treated with rat injured pancreatic extract and quercetin for 2 weeks. Insulin secretion was measured by ELISA. Insulin expression and some islet factors were evaluated by RT-PCR. PDX1, a marker for β-cell function and differentiation, was evaluated by both immunocytochemistry and Western blot. β-cell count was determined by stereology and cell count assay. ELISA showed significant differences in insulin secretion in the cells treated with RIPE + 20 μM quercetin (0.55 ± 0.01 µg/L) compared with the cells treated with RIPE alone (0.48 ± 0.01 µg/L) (P = 0.026). RT-PCR results confirmed insulin expression in both groups. PDX1 protein was detected in both groups by Western blot and immunocytochemistry. Stereology results showed a significant increase in β-cell number in the RIPE + quercetin-treated cells (47 ± 2.0) when compared with RIPE treatment alone (44 ± 2.5) (P = 0.015). Quercetin has a strengthening effect on the differentiation of rat bone marrow mesenchymal stem cells into β-cells and increases insulin secretion from the differentiated β-cells in vitro.

Importance of the stem cell microenvironment for ophthalmological cell-based therapy

PubMed Central

Wan, Peng-Xia; Wang, Bo-Wen; Wang, Zhi-Chong

2015-01-01

Cell therapy is a promising treatment for diseases that are caused by cell degeneration or death. The cells for clinical transplantation are usually obtained by culturing healthy allogeneic or exogenous tissue in vitro. However, for diseases of the eye, obtaining the adequate number of cells for clinical transplantation is difficult due to the small size of tissue donors and the frequent needs of long-term amplification of cells in vitro, which results in low cell viability after transplantation. In addition, the transplanted cells often develop fibrosis or degrade and have very low survival. Embryonic stem cells (ESCs) and induced pluripotent stem cells (iPS) are also promising candidates for cell therapy. Unfortunately, the differentiation of ESCs can bring immune rejection, tumorigenicity and undesired differentiated cells, limiting its clinical application. Although iPS cells can avoid the risk of immune rejection caused by ES cell differentiation post-transplantation, the low conversion rate, the risk of tumor formation and the potentially unpredictable biological changes that could occur through genetic manipulation hinder its clinical application. Thus, the desired clinical effect of cell therapy is impaired by these factors. Recent research findings recognize that the reason for low survival of the implanted cells not only depends on the seeded cells, but also on the cell microenvironment, which determines the cell survival, proliferation and even reverse differentiation. When used for cell therapy, the transplanted cells need a specific three-dimensional structure to anchor and specific extra cellular matrix components in addition to relevant cytokine signaling to transfer the required information to support their growth. These structures present in the matrix in which the stem cells reside are known as the stem cell microenvironment. The microenvironment interaction with the stem cells provides the necessary homeostasis for cell maintenance and growth. A large number of studies suggest that to explore how to reconstruct the stem cell microenvironment and strengthen its combination with the transplanted cells are key steps to successful cell therapy. In this review, we will describe the interactions of the stem cell microenvironment with the stem cells, discuss the importance of the stem cell microenvironment for cell-based therapy in ocular diseases, and introduce the progress of stem cell-based therapy for ocular diseases. PMID:25815128

Senescence-associated reprogramming promotes cancer stemness.

PubMed

Milanovic, Maja; Fan, Dorothy N Y; Belenki, Dimitri; Däbritz, J Henry M; Zhao, Zhen; Yu, Yong; Dörr, Jan R; Dimitrova, Lora; Lenze, Dido; Monteiro Barbosa, Ines A; Mendoza-Parra, Marco A; Kanashova, Tamara; Metzner, Marlen; Pardon, Katharina; Reimann, Maurice; Trumpp, Andreas; Dörken, Bernd; Zuber, Johannes; Gronemeyer, Hinrich; Hummel, Michael; Dittmar, Gunnar; Lee, Soyoung; Schmitt, Clemens A

2018-01-04

Cellular senescence is a stress-responsive cell-cycle arrest program that terminates the further expansion of (pre-)malignant cells. Key signalling components of the senescence machinery, such as p16 INK4a , p21 CIP1 and p53, as well as trimethylation of lysine 9 at histone H3 (H3K9me3), also operate as critical regulators of stem-cell functions (which are collectively termed 'stemness'). In cancer cells, a gain of stemness may have profound implications for tumour aggressiveness and clinical outcome. Here we investigated whether chemotherapy-induced senescence could change stem-cell-related properties of malignant cells. Gene expression and functional analyses comparing senescent and non-senescent B-cell lymphomas from Eμ-Myc transgenic mice revealed substantial upregulation of an adult tissue stem-cell signature, activated Wnt signalling, and distinct stem-cell markers in senescence. Using genetically switchable models of senescence targeting H3K9me3 or p53 to mimic spontaneous escape from the arrested condition, we found that cells released from senescence re-entered the cell cycle with strongly enhanced and Wnt-dependent clonogenic growth potential compared to virtually identical populations that had been equally exposed to chemotherapy but had never been senescent. In vivo, these previously senescent cells presented with a much higher tumour initiation potential. Notably, the temporary enforcement of senescence in p53-regulatable models of acute lymphoblastic leukaemia and acute myeloid leukaemia was found to reprogram non-stem bulk leukaemia cells into self-renewing, leukaemia-initiating stem cells. Our data, which are further supported by consistent results in human cancer cell lines and primary samples of human haematological malignancies, reveal that senescence-associated stemness is an unexpected, cell-autonomous feature that exerts its detrimental, highly aggressive growth potential upon escape from cell-cycle blockade, and is enriched in relapse tumours. These findings have profound implications for cancer therapy, and provide new mechanistic insights into the plasticity of cancer cells.

iPSC-derived cancer stem cells provide a model of tumor vasculature.

PubMed

Prieto-Vila, Marta; Yan, Ting; Calle, Anna Sanchez; Nair, Neha; Hurley, Laura; Kasai, Tomonari; Kakuta, Hiroki; Masuda, Junko; Murakami, Hiroshi; Mizutani, Akifumi; Seno, Masaharu

2016-01-01

To grow beyond a size of approximately 1-2 mm 3 , tumor cells activate many processes to develop blood vasculature. Growing evidences indicate that the formation of the tumor vascular network is very complex, and is not restricted to angiogenesis. Cancer cell-derived tumor vasculatures have been recently described. Among them, endothelial differentiation of tumor cells have been directly related to cancer stem cells, which are cells within a tumor that possess the capacity to self-renew, and to exhibit multipotential heterogeneous lineages of cancer cells. Vasculogenic mimicry has been described to be formed by cancer cells expressing stemness markers. Thus, cancer stem cells have been proposed to contribute to vasculogenic mimicry, though its relation is yet to be clarified. Here, we analyzed the tumor vasculature by using a model of mouse cancer stem cells, miPS-LLCcm cells, which we have previously established from mouse induced pluripotent stem cells and we introduced the DsRed gene in miPS-LLCcm to trace them in vivo . Various features of vasculature were evaluated in ovo , in vitro , and in vivo . The tumors formed in allograft nude mice exhibited angiogenesis in chick chorioallantoic membrane assay. In those tumors, along with penetrated host endothelial vessels, we detected endothelial differentiation from cancer stem cells and formation of vasculogenic mimicry. The angiogenic factors such as VEGF-A and FGF2 were expressed predominantly in the cancer stem cells subpopulation of miPS-LLCcm cells. Our results suggested that cancer stem cells play key roles in not only the recruitment of host endothelial vessels into tumor, but also in maturation of endothelial linage of cancer stem cell's progenies. Furthermore, the undifferentiated subpopulation of the miPS-LLCcm participates directly in the vasculogenic mimicry formation. Collectively, we show that miPS-LLCcm cells have advantages to further study tumor vasculature and to develop novel targeting strategies in the future.

The Use Of Laser Irradiation To Stimulate Adipose Derived Stem Cell Proliferation And Differentiation For Use In Autologous Grafts

NASA Astrophysics Data System (ADS)

Abrahamse, Heidi

2009-09-01

Stem cells are characterized by the qualities of self-renewal, long term viability, and the ability to differentiate into various cell types. Historically, stem cells have been isolated from the inner cell mass of blastocysts and harvesting these cells resulted in the death of the embryo leading to religious, political and ethical issues. The identification and subsequent isolation of adult stem cells from bone marrow stroma have been welcomed as an alternate source for stem cells. The clinical use of Mesenchymal Stem Cells (MSCs) presented problems such as limited cell number, pain and morbidity upon isolation. Adipose tissue is derived from the mesenchyme, is easily isolated, a reliable source of stem cells and able to differentiate into different cell types including smooth muscle. Over the past few years, the identification and characterization of stem cells has led the potential use of these cells as a promising alternative to cell replacement therapy. Smooth muscle is a major component of human tissues and is essential for the normal functioning of many different organs. Low intensity laser irradiation has been shown to increase viability, protein expression and migration of stem cells in vitro, and to stimulate proliferation of various types of stem cells. In addition, the use of laser irradiation to stimulate differentiation in the absence of growth factors has also been demonstrated in normal human neural progenitor cells (NHNPCs) in vitro where NHNPCs are not only capable of being sustained by light in the absence of growth factors, but that they are also able to differentiate normally as assessed by neurite formation. Our work has focused on the ability of laser irradiation to proliferate adipose derived stem cells (ADSCs), maintain ADSC character and increase the rate and maintenance of differentiation of ADSCs into smooth muscle and skin fibroblast cells. Current studies are also investigating the effect of different irradiation wavelengths and fluences on ADSC viability and proliferation. This paper reviews the development of MSCs as potential therapeutic interventions such as autologous grafts as well as the contribution of low intensity laser irradiation on the maintenance of these cells.

Synergetic effect of topological cue and periodic mechanical tension-stress on osteogenic differentiation of rat bone mesenchymal stem cells.

PubMed

Liu, Yao; Yang, Guang; Ji, Huanzhong; Xiang, Tao; Luo, En; Zhou, Shaobing

2017-06-01

Mesenchymal stem cells (MSCs) are able to self-renew and differentiate into tissues of mesenchymal origin, making them to be significant for cell-based therapies, such as metabolic bone diseases and bone repair. Regulating the differentiation of MSCs is significant for bone regeneration. Electrospun fibers mimicking natural extracellular matrix (ECM), is an effective artificial ECM to regulate the behaviors and fates of MSCs. The aligned electrospun fibers can modulate polar cell pattern of bone mesenchymal stem cells, which leads to more obvious osteogenic differentiation. Apart from the topographic effect of electrospun fibers, mechanical cues can also intervene the cell behaviors. In this study, the osteogenic differentiation of rat bone mesenchymal stem cells was evaluated, which were cultured on aligned/random electrospun fiber mats materials under mechanical tension intervention. Scanning electron microscope and immune-fluorescent staining were used to directly observe the polarity changing of cellular morphology and cytoskeleton. The results proved that aligned electrospun fibers could be more conducive to promote osteogenic differentiation of rat bone mesenchymal stem cells and this promotion of osteogenic differentiation was enhanced by tension intervention. These results were correlated to the quantitative real-time PCR assay. In general, culturing rat bone mesenchymal stem cells on electrospun fibers under the intervention of mechanical tension is an effective way to mimic a more real cellular microenvironment. Copyright © 2017 Elsevier B.V. All rights reserved.

A Bibliometric Analysis of Publications on Pluripotent Stem Cell Research

PubMed Central

Lin, Changshuan L.; Ho, Yuh-Shan

2015-01-01

Objective Human pluripotent stem cells are self-renewing cells with the ability to differentiate into a variety of cells and are viewed to have great potential in the field of regenerative medicine. Research in pluripotent stem cells holds great promise for patient specific therapy in various diseases. In this study, pluripotent stem cell articles published from 1991 to 2012 were screened and retrieved from Science Citation Index Expanded (SCI-EXPANDED). Materials and Methods In this retrospective study, the publication trend, citation trends for top articles, distributions of journals and Web of Science categories were analyzed. Five bibliometric indicators including total articles, independent articles, collaborative articles, first author articles, and corresponding author articles were applied to compare publications between countries and institutions. Results The impact of top articles changed from year to year. Top cited articles in previous publication years were not the same as recent years. "Induced pluripotent stem cell (s)" and "embryonic stem cell (s)" were the most used author keywords in pluripotent stem cell research. In addition, the winner of the Nobel Prize in physiology or medicine in 2012, Prof. Shinya Yamanaka, published four of the top ten most frequently cited articles. Conclusion The comprehensive analysis of highly cited articles in the stem cell field could identify milestones and important contributors, giving a historic perspective on scientific progress. PMID:25870835

Conditioned medium as a strategy for human stem cells chondrogenic differentiation.

PubMed

Alves da Silva, M L; Costa-Pinto, A R; Martins, A; Correlo, V M; Sol, P; Bhattacharya, M; Faria, S; Reis, R L; Neves, Nuno M

2015-06-01

Paracrine signalling from chondrocytes has been reported to increase the synthesis and expression of cartilage extracellular matrix (ECM) by stem cells. The use of conditioned medium obtained from chondrocytes for stimulating stem cells chondrogenic differentiation may be a very interesting alternative for moving into the clinical application of these cells, as chondrocytes could be partially replaced by stem cells for this type of application. In the present study we aimed to achieve chondrogenic differentiation of two different sources of stem cells using conditioned medium, without adding growth factors. We tested both human bone marrow-derived mesenchymal stem cells (hBSMCs) and human Wharton's jelly-derived stem cells (hWJSCs). Conditioned medium obtained from a culture of human articular chondrocytes was used to feed the cells during the experiment. Cultures were performed in previously produced three-dimensional (3D) scaffolds, composed of a blend of 50:50 chitosan:poly(butylene succinate). Both types of stem cells were able to undergo chondrogenic differentiation without the addition of growth factors. Cultures using hWJSCs showed significantly higher GAGs accumulation and expression of cartilage-related genes (aggrecan, Sox9 and collagen type II) when compared to hBMSCs cultures. Conditioned medium obtained from articular chondrocytes induced the chondrogenic differentiation of MSCs and ECM formation. Obtained results showed that this new strategy is very interesting and should be further explored for clinical applications. Copyright © 2013 John Wiley & Sons, Ltd.

Pancreatic stellate cells enhance stem cell-like phenotypes in pancreatic cancer cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hamada, Shin; Masamune, Atsushi, E-mail: amasamune@med.tohoku.ac.jp; Takikawa, Tetsuya

2012-05-04

Highlights: Black-Right-Pointing-Pointer Pancreatic stellate cells (PSCs) promote the progression of pancreatic cancer. Black-Right-Pointing-Pointer Pancreatic cancer cells co-cultured with PSCs showed enhanced spheroid formation. Black-Right-Pointing-Pointer Expression of stem cell-related genes ABCG2, Nestin and LIN28 was increased. Black-Right-Pointing-Pointer Co-injection of PSCs enhanced tumorigenicity of pancreatic cancer cells in vivo. Black-Right-Pointing-Pointer This study suggested a novel role of PSCs as a part of the cancer stem cell niche. -- Abstract: The interaction between pancreatic cancer cells and pancreatic stellate cells (PSCs), a major profibrogenic cell type in the pancreas, is receiving increasing attention. There is accumulating evidence that PSCs promote the progression ofmore » pancreatic cancer by increasing cancer cell proliferation and invasion as well as by protecting them from radiation- and gemcitabine-induced apoptosis. Recent studies have identified that a portion of cancer cells, called 'cancer stem cells', within the entire cancer tissue harbor highly tumorigenic and chemo-resistant phenotypes, which lead to the recurrence after surgery or re-growth of the tumor. The mechanisms that maintain the 'stemness' of these cells remain largely unknown. We hypothesized that PSCs might enhance the cancer stem cell-like phenotypes in pancreatic cancer cells. Indirect co-culture of pancreatic cancer cells with PSCs enhanced the spheroid-forming ability of cancer cells and induced the expression of cancer stem cell-related genes ABCG2, Nestin and LIN28. In addition, co-injection of PSCs enhanced tumorigenicity of pancreatic cancer cells in vivo. These results suggested a novel role of PSCs as a part of the cancer stem cell niche.« less

Differential Radiosensitizing Effect of Valproic Acid in Differentiation Versus Self-Renewal Promoting Culture Conditions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Debeb, Bisrat G.; Xu Wei; Mok, Henry

2010-03-01

Purpose: It has been shown that valproic acid (VA) enhances the proliferation and self-renewal of normal hematopoietic stem cells and that breast cancer stem/progenitor cells can be resistant to radiation. From these data, we hypothesized that VA would fail to radiosensitize breast cancer stem/progenitor cells grown to three-dimensional (3D) mammospheres. Methods and Materials: We used the MCF7 breast cancer cell line grown under stem cell-promoting culture conditions (3D mammosphere) and standard nonstem cell monolayer culture conditions (two-dimensional) to examine the effect of pretreatment with VA on radiation sensitivity in clonogenic survival assays and on the expression of embryonic stem cellmore » transcription factors. Results: 3D-cultured MCF-7 cells expressed higher levels of Oct4, Nanog, and Sox2. The 3D passage enriched self-renewal and increased radioresistance in the 3D mammosphere formation assays. VA radiosensitized adherent cells but radioprotected 3D cells in single-fraction clonogenic assays. Moreover, fractionated radiation sensitized VA-treated adherent MCF7 cells but did not have a significant effect on VA-treated single cells grown to mammospheres. Conclusion: We have concluded that VA might preferentially radiosensitize differentiated cells compared with those expressing stem cell surrogates and that stem cell-promoting culture is a useful tool for in vitro evaluation of novel cancer therapeutic agents and radiosensitizers.« less

The SKI proto-oncogene enhances the in vivo repopulation of hematopoietic stem cells and causes myeloproliferative disease.

PubMed

Singbrant, Sofie; Wall, Meaghan; Moody, Jennifer; Karlsson, Göran; Chalk, Alistair M; Liddicoat, Brian; Russell, Megan R; Walkley, Carl R; Karlsson, Stefan

2014-04-01

The proto-oncogene SKI is highly expressed in human myeloid leukemia and also in murine hematopoietic stem cells. However, its operative relevance in these cells remains elusive. We have over-expressed SKI to define its intrinsic role in hematopoiesis and myeloid neoplasms, which resulted in a robust competitive advantage upon transplantation, a complete dominance of the stem and progenitor compartments, and a marked enhancement of myeloid differentiation at the expense of other lineages. Accordingly, enforced expression of SKI induced a gene signature associated with hematopoietic stem cells and myeloid differentiation, as well as hepatocyte growth factor signaling. Here we demonstrate that, in contrast to what has generally been assumed, the significant impact of SKI on hematopoiesis is independent of its ability to inhibit TGF-beta signaling. Instead, myeloid progenitors expressing SKI are partially dependent on functional hepatocyte growth factor signaling. Collectively our results demonstrate that SKI is an important regulator of hematopoietic stem cell activity and its overexpression leads to myeloproliferative disease.

The SKI proto-oncogene enhances the in vivo repopulation of hematopoietic stem cells and causes myeloproliferative disease

PubMed Central

Singbrant, Sofie; Wall, Meaghan; Moody, Jennifer; Karlsson, Göran; Chalk, Alistair M.; Liddicoat, Brian; Russell, Megan R.; Walkley, Carl R.; Karlsson, Stefan

2014-01-01

The proto-oncogene SKI is highly expressed in human myeloid leukemia and also in murine hematopoietic stem cells. However, its operative relevance in these cells remains elusive. We have over-expressed SKI to define its intrinsic role in hematopoiesis and myeloid neoplasms, which resulted in a robust competitive advantage upon transplantation, a complete dominance of the stem and progenitor compartments, and a marked enhancement of myeloid differentiation at the expense of other lineages. Accordingly, enforced expression of SKI induced a gene signature associated with hematopoietic stem cells and myeloid differentiation, as well as hepatocyte growth factor signaling. Here we demonstrate that, in contrast to what has generally been assumed, the significant impact of SKI on hematopoiesis is independent of its ability to inhibit TGF-beta signaling. Instead, myeloid progenitors expressing SKI are partially dependent on functional hepatocyte growth factor signaling. Collectively our results demonstrate that SKI is an important regulator of hematopoietic stem cell activity and its overexpression leads to myeloproliferative disease. PMID:24415629

Differentiation of Human Dental Stem Cells Reveal a Role for microRNA-218

PubMed Central

Gay, Isabel; Cavender, Adriana; Peto, David; Sun, Zhao; Speer, Aline; Cao, Huojun; Amendt, Brad A.

2013-01-01

Background Regeneration of the lost periodontium is the ultimate goal of periodontal therapy. Advances in tissue engineering have demonstrated the multilineage potential and plasticity of adult stem cells located in the periodontal apparatus. However, it remains unclear how epigenetic mechanisms controlling signals determine tissue specification and cell lineage decisions. To date, no data is available on micro-RNAs (miRNAs) activity behind human-derived dental stem cells. Methods In this study, we isolated periodontal ligament stem cells (PDLSCs), dental pulp stem cells (DPSCs), and gingival stem cells (GSCs) from extracted third molars; human bone marrow stem cells (BMSCs) were used as a positive control. The expression of OCT4A and NANOG was confirmed in these undifferentiated cells. All cells were cultured under osteogenic inductive conditions and RUNX2 expression was analyzed as a marker of mineralized tissue differentiation. A miRNA expression profile was obtained at baseline and after osteogenic induction in all cell types. Results RUNX2 expression demonstrated the successful osteogenic induction of all cell types, which was confirmed by alizarin red stain. The analysis of 765 miRNAs demonstrated a shift in miRNA expression occurred in all four stem cell types, including a decrease in hsa-mir-218 across all differentiated cell populations. Hsa-mir-218 targets RUNX2 and decreases RUNX2 expression in undifferentiated human dental stem cells (DSCs). DSC mineralized tissue type differentiation is associated with a decrease in hsa-mir-218 expression. Conclusions These data reveal a miRNA regulated pathway for the differentiation of human DSCs and a select network of human microRNAs that control DSC osteogenic differentiation. PMID:23662917

The human urothelium consists of multiple clonal units, each maintained by a stem cell.

PubMed

Gaisa, Nadine T; Graham, Trevor A; McDonald, Stuart A C; Cañadillas-Lopez, Sagrario; Poulsom, Richard; Heidenreich, Axel; Jakse, Gerhard; Tadrous, Paul J; Knuechel, Ruth; Wright, Nicholas A

2011-10-01

Little is known about the clonal architecture of human urothelium. It is likely that urothelial stem cells reside within the basal epithelial layer, yet lineage tracing from a single stem cell as a means to show the presence of a urothelial stem cell has never been performed. Here, we identify clonally related cell areas within human bladder mucosa in order to visualize epithelial fields maintained by a single founder/stem cell. Sixteen frozen cystectomy specimens were serially sectioned. Patches of cells deficient for the mitochondrially encoded enzyme cytochrome c oxidase (CCO) were identified using dual-colour enzyme histochemistry. To show that these patches represent clonal proliferations, small CCO-proficient and -deficient areas were individually laser-capture microdissected and the entire mitochondrial genome (mtDNA) in each area was PCR amplified and sequenced to identify mtDNA mutations. Immunohistochemistry was performed for the different cell layers of the urothelium and adjacent mesenchyme. CCO-deficient patches could be observed in normal urothelium of all cystectomy specimens. The two-dimensional length of these negative patches varied from 2-3 cells (about 30 µm) to 4.7 mm. Each cell area within a CCO-deficient patch contained an identical somatic mtDNA mutation, indicating that the patch was a clonal unit. Patches contained all the mature cell differentiation stages present in the urothelium, suggesting the presence of a stem cell. Our results demonstrate that the normal mucosa of human bladder contains stem cell-derived clonal units that actively replenish the urothelium during ageing. The size of the clonal unit attributable to each stem cell was broadly distributed, suggesting replacement of one stem cell clone by another. Copyright © 2011 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Epimorphin Regulates the Intestinal Stem Cell Niche via Effects on the Stromal Microenvironment.

PubMed

Vishy, Courtney E; Swietlicki, Elzbieta A; Gazit, Vered; Amara, Suneetha; Heslop, Gabriela; Lu, Jianyun; Levin, Marc S; Rubin, Deborah C

2018-04-06

Stem cell therapy is a potential therapeutic approach for disorders characterized by intestinal injury or loss of functional surface area. Stem cell function and proliferation are mediated by the stem cell niche. Stromal cells such as intestinal subepithelial myofibroblasts (ISEMFs) are important but poorly studied components of the stem cell niche. To examine the role of ISEMFs, we have previously generated mice with deletion of epimorphin (Epim), an ISEMF protein and member of the syntaxin family of intracellular vesicle docking proteins that regulate cell secretion. Herein we explore the mechanisms for previous observations that Epim deletion increases gut crypt cell proliferation, crypt fission and small bowel length in vivo. Stem cell derived crypt culture techniques were used to explore the interaction between enteroids and myofibroblasts from Epim -/- and WT mice. Enteroids co-cultured with ISEMFS had increased growth and crypt-like budding compared to enteroids cultured without stromal support. Epim deletion in ISEMFs resulted in increased enteroid budding and surface area compared to co-cultures with WT ISEMFs. In primary crypt cultures, Epim -/- enteroids had significantly increased surface area and budding compared WTs. However stem cell assays comparing the number of Epim -/- vs WT colony forming units after first passage showed no differences in the absence of ISEMF support. Epim -/- vs. WT ISEMFs had increased Wnt4 expression and addition of Wnt4 to WT co-cultures enhanced budding. We conclude that ISEMFs play an important role in the stem cell niche. Epim regulates stem cell proliferation and differentiation via stromal contributions to the niche microenvironment.

Modeling the Chagas’ disease after stem cell transplantation

NASA Astrophysics Data System (ADS)

Galvão, Viviane; Miranda, José Garcia Vivas

2009-04-01

A recent model for Chagas’ disease after stem cell transplantation is extended for a three-dimensional multi-agent-based model. The computational model includes six different types of autonomous agents: inflammatory cell, fibrosis, cardiomyocyte, proinflammatory cytokine tumor necrosis factor- α, Trypanosoma cruzi, and bone marrow stem cell. Only fibrosis is fixed and the other types of agents can move randomly through the empty spaces using the three-dimensional Moore neighborhood. Bone marrow stem cells can promote apoptosis in inflammatory cells, fibrosis regression and can differentiate in cardiomyocyte. T. cruzi can increase the number of inflammatory cells. Inflammatory cells and tumor necrosis factor- α can increase the quantity of fibrosis. Our results were compared with experimental data giving a fairly fit and they suggest that the inflammatory cells are important for the development of fibrosis.

Endogenous, very small embryonic-like stem cells: critical review, therapeutic potential and a look ahead.

PubMed

Bhartiya, Deepa; Shaikh, Ambreen; Anand, Sandhya; Patel, Hiren; Kapoor, Sona; Sriraman, Kalpana; Parte, Seema; Unni, Sreepoorna

2016-12-01

Both pluripotent very small embryonic-like stem cells (VSELs) and induced pluripotent stem (iPS) cells were reported in 2006. In 2012, a Nobel Prize was awarded for iPS technology whereas even today the very existence of VSELs is not well accepted. The underlying reason is that VSELs exist in low numbers, remain dormant under homeostatic conditions, are very small in size and do not pellet down at 250-280g. The VSELs maintain life-long tissue homeostasis, serve as a backup pool for adult stem cells and are mobilized under stress conditions. An imbalance in VSELs function (uncontrolled proliferation) may result in cancer. The electronic database 'Medline/Pubmed' was systematically searched with the subject heading term 'very small embryonic-like stem cells'. The most primitive stem cells that undergo asymmetric cell divisions to self-renew and give rise to progenitors still remain elusive in the hematopoietic system and testes, while the presence of stem cells in ovary is still being debated. We propose to review the available literature on VSELs, the methods of their isolation and characterization, their ontogeny, how they compare with embryonic stem (ES) cells, primordial germ cells (PGCs) and iPS cells, and their role in maintaining tissue homeostasis. The review includes a look ahead on how VSELs will result in paradigm shifts in basic reproductive biology. Adult tissue-specific stem cells including hematopoietic, spermatogonial, ovarian and mesenchymal stem cells have good proliferation potential and are indeed committed progenitors (with cytoplasmic OCT-4), which arise by asymmetric cell divisions of pluripotent VSELs (with nuclear OCT-4). VSELs are the most primitive stem cells and postulated to be an overlapping population with the PGCs. Rather than migrating only to the gonads, PGCs migrate and survive in various adult body organs throughout life as VSELs. VSELs express both pluripotent and PGC-specific markers and are epigenetically and developmentally more mature compared with ES cells obtained from the inner cell mass of a blastocyst-stage embryo. As a result, VSELs readily differentiate into three embryonic germ layers and spontaneously give rise to both sperm and oocytes in vitro. Like PGCs, VSELs do not divide readily in culture, nor produce teratoma or integrate in the developing embryo. But this property of being relatively quiescent allows endogenous VSELs to survive various kinds of toxic insults. VSELs that survive oncotherapy can be targeted to induce endogenous regeneration of non-functional gonads. Transplanting healthy niche (mesenchymal) cells have resulted in improved gonadal function and live births. Being quiescent, VSELs possibly do not accumulate genomic (nuclear or mitochondrial) mutations and thus may be ideal endogenous, pluripotent stem cell candidates for regenerative and reproductive medicine. The presence of VSELs in adult gonads and the fact that they survive oncotherapy may obviate the need to bank gonadal tissue for fertility preservation prior to oncotherapy. VSELs and their ability to undergo spermatogenesis/neo-oogenesis in the presence of a healthy niche will help identify newer strategies toward fertility restoration in cancer survivors, delaying menopause and also enabling aged mothers to have better quality eggs. © The Author 2016. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Stable chromosomal aberrations in haemopoietic stem cells in the blood of radiation accident victims.

PubMed

Kreja, L; Greulich, K M; Fliedner, T M; Heinze, B

1999-10-01

The detection of long-term persistent chromosome aberrations in circulating haemopoietic stem cells after accidental radiation exposure. Peripheral blood samples from highly exposed persons were collected 7-25 years after the radiation accidents in Moscow (1971), Kazan (1975) and Chernobyl (1996). Haemopoietic blood stem cells were analysed when investigating individual colonies derived from haemopoietic progenitor cells: burst-forming units-erythroid (BFU-E), granulocyte-macrophage-colony-forming cells (GM-CFC) and multipotent granulocyte-erythrocyte-macrophage- megakaryocyte-colony-forming cells (GEMM-CFC). Colony formation was obtained in methylcellulose cultures. Chromosome preparations in single colonies were performed using a microtechnique. Nine patients were investigated at 1 to 4 follow-up time points after radiation exposure. Three hundred and thirty-four single colonies were analyzed resulting in 1375 mitoses. It was found that colonies showed chromosome aberrations (ChA) up to 25 years after radiation exposure by classical cytogenetics and by fluorescence in situ hybridization (FISH). Stable aberrations were detected in 21% of colonies. They were clonal in 19% of colonies, i.e. the same abnormality was found in all cells derived from a single colony. In 2% of colonies ChA were stable but non-clonal; unstable ChA were not observed. The results indicate that blood-derived haemopoietic stem cells may serve as a biological indicator to detect radiation-induced ChA. Since they are considered to be in dynamic and functional exchange with stem cells in the medullary sites of blood cell formation such as bone marrow, the use of blood stem cells as a marker of radiation effects should be explored to assess the repair status of the stem cell pool as such.

MtDNA depleted PC3 cells exhibit Warburg effect and cancer stem cell features

PubMed Central

Li, Xiaoran; Zhong, Yali; Lu, Jie; Axcrona, Karol; Eide, Lars; Syljuåsen, Randi G.; Peng, Qian; Wang, Junbai; Zhang, Hongquan; Goscinski, Mariusz Adam; Kvalheim, Gunnar; Nesland, Jahn M.; Suo, Zhenhe

2016-01-01

Reducing mtDNA content was considered as a critical step in the metabolism restructuring for cell stemness restoration and further neoplastic development. However, the connections between mtDNA depletion and metabolism reprograming-based cancer cell stemness in prostate cancers are still lack of studies. Here, we demonstrated that human CRPC cell line PC3 tolerated high concentration of the mtDNA replication inhibitor ethidium bromide (EtBr) and the mtDNA depletion triggered a universal metabolic remodeling process. Failure in completing that process caused lethal consequences. The mtDNA depleted (MtDP) PC3 cells could be steadily maintained in the special medium in slow cycling status. The MtDP PC3 cells contained immature mitochondria and exhibited Warburg effect. Furthermore, the MtDP PC3 cells were resistant to therapeutic treatments and contained greater cancer stem cell-like subpopulations: CD44+, ABCG2+, side-population and ALDHbright. In conclusion, these results highlight the association of mtDNA content, mitochondrial function and cancer cell stemness features. PMID:27248169

Chapter 17 Sterile Plate-Based Vitrification of Adherent Human Pluripotent Stem Cells and Their Derivatives Using the TWIST Method.

PubMed

Neubauer, Julia C; Stracke, Frank; Zimmermann, Heiko

2017-01-01

Due to their high biological complexity, e.g., their close cell-to-cell contacts, cryopreservation of human pluripotent stem cells with standard slow-rate protocols often is inefficient and can hardly be standardized. Vitrification that means ultrafast freezing already showed very good viability and recovery rates for this sensitive cell system, but is only applicable for low cell numbers, bears a high risk of contamination, and can hardly be implemented under GxP regulations. In this chapter, a sterile plate-based vitrification method for adherent pluripotent stem cells and their derivatives is presented based on a procedure and device for human embryonic stem cells developed by Beier et al. (Cryobiology 66:8-16, 2013). This protocol overcomes the limitations of conventional vitrification procedures resulting in the highly efficient preservation of ready-to-use adherent pluripotent stem cells with the possibility of vitrifying cells in multi-well formats for direct application in high-throughput screenings.

Regulation of stem cell-based therapies in Canada: current issues and concerns.

PubMed

von Tigerstrom, Barbara; Nguyen, Thu Minh; Knoppers, Bartha Maria

2012-09-01

Stem cell therapies offer enormous potential for the treatment of a wide range of diseases and conditions. Despite the excitement over such advances, regulators are faced with the challenge of determining criteria to ensure stem cells and their products are safe and effective for human use. However, stem cell-based products and therapies present unique regulatory challenges because standard drug development models do not wholly apply given the complexity and diversity of these products and therapies. As a result, regulatory requirements are often unclear and ambiguous creating unnecessary barriers for research. In order to better understand the barriers that might affect Canadian stem cell researchers, we sought feedback from stakeholders regarding areas of uncertainty or concern about existing regulatory oversight of cell therapies. A selection of Canadian researchers and clinicians working in the area of stem cell research were interviewed to assess certain key questions: 1) whether current regulatory requirements are easily accessible and well understood; 2) whether regulatory requirements create important challenges or barriers; and 3) whether there is a need for further guidance on the issue. The results of this survey are summarized and compared to issues and concerns experienced in other countries, as reported in the literature, to identify challenges which may be on the horizon and to provide possible solutions for regulatory reform.

Cryopreserved, Xeno-Free Human Umbilical Cord Mesenchymal Stromal Cells Reduce Lung Injury Severity and Bacterial Burden in Rodent Escherichia coli-Induced Acute Respiratory Distress Syndrome.

PubMed

Curley, Gerard F; Jerkic, Mirjana; Dixon, Steve; Hogan, Grace; Masterson, Claire; O'Toole, Daniel; Devaney, James; Laffey, John G

2017-02-01

Although mesenchymal stem/stromal cells represent a promising therapeutic strategy for acute respiratory distress syndrome, clinical translation faces challenges, including scarcity of bone marrow donors, and reliance on bovine serum during mesenchymal stem/stromal cell proliferation. We wished to compare mesenchymal stem/stromal cells from human umbilical cord, grown in xeno-free conditions, with mesenchymal stem/stromal cells from human bone marrow, in a rat model of Escherichia coli pneumonia. In addition, we wished to determine the potential for umbilical cord-mesenchymal stem/stromal cells to reduce E. coli-induced oxidant injury. Randomized animal study. University research laboratory. Male Sprague-Dawley rats. Acute respiratory distress syndrome was induced in rats by intratracheal instillation of E. coli (1.5-2 × 10 CFU/kg). "Series 1" compared the effects of freshly thawed cryopreserved umbilical cord-mesenchymal stem/stromal cells with bone marrow-mesenchymal stem/stromal cells on physiologic indices of lung injury, cellular infiltration, and E. coli colony counts in bronchoalveolar lavage. "Series 2" examined the effects of cryopreserved umbilical cord-mesenchymal stem/stromal cells on survival, as well as measures of injury, inflammation and oxidant stress, including production of reactive oxidative species, reactive oxidative species scavenging by superoxide dismutase-1 and superoxide dismutase-2. In "Series 1," animals subjected to E. coli pneumonia who received umbilical cord-mesenchymal stem/stromal cells had improvements in oxygenation, respiratory static compliance, and wet-to-dry ratios comparable to bone marrow-mesenchymal stem/stromal cell treatment. E. coli colony-forming units in bronchoalveolar lavage were reduced in both cell therapy groups, despite a reduction in bronchoalveolar lavage neutrophils. In series 2, umbilical cord-mesenchymal stem/stromal cells enhanced animal survival and decreased alveolar protein and proinflammatory cytokine concentrations, whereas increasing interleukin-10 concentrations. Umbilical cord-mesenchymal stem/stromal cell therapy decreased nicotinamide adenine dinucleotide phosphate-oxidase 2 and inducible nitric oxide synthase and enhanced lung concentrations of superoxide dismutase-2, thereby reducing lung tissue reactive oxidative species concentrations. Our results demonstrate that freshly thawed cryopreserved xeno-free human umbilical cord-mesenchymal stem/stromal cells reduce the severity of rodent E. coli-induced acute respiratory distress syndrome. Umbilical cord-mesenchymal stem/stromal cells, therefore, represent an attractive option for future clinical trials in acute respiratory distress syndrome.

Oxidative stress of neural, hematopoietic, and stem cells: protection by natural compounds.

PubMed

Shytle, R Douglas; Ehrhart, Jared; Tan, Jun; Vila, Jennifer; Cole, Michael; Sanberg, Cyndy D; Sanberg, Paul R; Bickford, Paula C

2007-06-01

During natural aging, adult stem cells are known to have a reduced restorative capacity and are more vulnerable to oxidative stress resulting in a reduced ability of the body to heal itself. We report here that the proprietary natural product formulation, NT020, previously found to promote proliferation of human hematopoietic stem cells, reduced oxidative stress-induced apoptosis of murine neurons and microglial cells in vitro. Furthermore, when taken orally for 2 weeks, cultured bone marrow stem cells from these mice exhibited a dose-related reduction of oxidative stress-induced apoptosis. This preclinical study demonstrates that NT020 can act to promote healing via an interaction with stem cell populations and forms the basis of conducting a clinical trial to determine if NT020 exhibits similar health promoting effects in humans when used as a dietary supplement.

Transcriptional programming during cell wall maturation in the expanding Arabidopsis stem.

PubMed

Hall, Hardy; Ellis, Brian

2013-01-25

Plant cell walls are complex dynamic structures that play a vital role in coordinating the directional growth of plant tissues. The rapid elongation of the inflorescence stem in the model plant Arabidopsis thaliana is accompanied by radical changes in cell wall structure and chemistry, but analysis of the underlying mechanisms and identification of the genes that are involved has been hampered by difficulties in accurately sampling discrete developmental states along the developing stem. By creating stem growth kinematic profiles for individual expanding Arabidopsis stems we have been able to harvest and pool developmentally-matched tissue samples, and to use these for comparative analysis of global transcript profiles at four distinct phases of stem growth: the period of elongation rate increase, the point of maximum growth rate, the point of stem growth cessation and the fully matured stem. The resulting profiles identify numerous genes whose expression is affected as the stem tissues pass through these defined growth transitions, including both novel loci and genes identified in earlier studies. Of particular note is the preponderance of highly active genes associated with secondary cell wall deposition in the region of stem growth cessation, and of genes associated with defence and stress responses in the fully mature stem. The use of growth kinematic profiling to create tissue samples that are accurately positioned along the expansion growth continuum of Arabidopsis inflorescence stems establishes a new standard for transcript profiling analyses of such tissues. The resulting expression profiles identify a substantial number of genes whose expression is correlated for the first time with rapid cell wall extension and subsequent fortification, and thus provide an important new resource for plant biologists interested in gene discovery related to plant biomass accumulation.

The novel steroidal alkaloids dendrogenin A and B promote proliferation of adult neural stem cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Khalifa, Shaden A.M., E-mail: shaden.khalifa@ki.se; Medina, Philippe de; INSERM UMR 1037, Team “Sterol Metabolism and Therapeutic Innovations in Oncology”, Cancer Research Center of Toulouse, F-31052 Toulouse

2014-04-11

Highlights: • Dendrogenin A and B are new aminoalkyl oxysterols. • Dendrogenins stimulated neural stem cells proliferation. • Dendrogenins induce neuronal outgrowth from neurospheres. • Dendrogenins provide new therapeutic options for neurodegenerative disorders. - Abstract: Dendrogenin A (DDA) and dendrogenin B (DDB) are new aminoalkyl oxysterols which display re-differentiation of tumor cells of neuronal origin at nanomolar concentrations. We analyzed the influence of dendrogenins on adult mice neural stem cell proliferation, sphere formation and differentiation. DDA and DDB were found to have potent proliferative effects in neural stem cells. Additionally, they induce neuronal outgrowth from neurospheres during in vitro cultivation.more » Taken together, our results demonstrate a novel role for dendrogenins A and B in neural stem cell proliferation and differentiation which further increases their likely importance to compensate for neuronal cell loss in the brain.« less

Concise Review: Adult Mesenchymal Stem Cells, Adult Neural Crest Stem Cells, and Therapy of Neurological Pathologies: A State of Play

PubMed Central

Neirinckx, Virginie; Coste, Cécile; Rogister, Bernard

2013-01-01

Adult stem cells are endowed with in vitro multilineage differentiation abilities and constitute an attractive autologous source of material for cell therapy in neurological disorders. With regard to lately published results, the ability of adult mesenchymal stem cells (MSCs) and neural crest stem cells (NCSCs) to integrate and differentiate into neurons once inside the central nervous system (CNS) is currently questioned. For this review, we collected exhaustive data on MSC/NCSC neural differentiation in vitro. We then analyzed preclinical cell therapy experiments in different models for neurological diseases and concluded that neural differentiation is probably not the leading property of adult MSCs and NCSCs concerning neurological pathology management. A fine analysis of the molecules that are secreted by MSCs and NCSCs would definitely be of significant interest regarding their important contribution to the clinical and pathological recovery after CNS lesions. PMID:23486833

Isolation and Characterization of Canine Amniotic Membrane-Derived Multipotent Stem Cells

PubMed Central

Kim, Hyung-Sik; Kang, Kyung-Sun

2012-01-01

Recent studies have shown that amniotic membrane tissue is a rich source of stem cells in humans. In clinical applications, the amniotic membrane tissue had therapeutic effects on wound healing and corneal surface reconstruction. Here, we successfully isolated and identified multipotent stem cells (MSCs) from canine amniotic membrane tissue. We cultured the canine amniotic membrane-derived multipotent stem cells (cAM-MSCs) in low glucose DMEM medium. cAM-MSCs have a fibroblast-like shape and adhere to tissue culture plastic. We characterized the immunophenotype of cAM-MSCs by flow cytometry and measured cell proliferation by the cumulative population doubling level (CPDL). We performed differentiation studies for the detection of trilineage multipotent ability, under the appropriate culture conditions. Taken together, our results show that cAM-MSCs could be a rich source of stem cells in dogs. Furthermore, cAM-MSCs may be useful as a cell therapy application for veterinary regenerative medicine. PMID:23024756

Neural stem cells induce the formation of their physical niche during organogenesis

PubMed Central

Riebesehl, Bea F; Ambrosio, Elizabeth M; Stolper, Julian S; Lischik, Colin Q; Dross, Nicolas

2017-01-01

Most organs rely on stem cells to maintain homeostasis during post-embryonic life. Typically, stem cells of independent lineages work coordinately within mature organs to ensure proper ratios of cell types. Little is known, however, on how these different stem cells locate to forming organs during development. Here we show that neuromasts of the posterior lateral line in medaka are composed of two independent life-long lineages with different embryonic origins. Clonal analysis and 4D imaging revealed a hierarchical organisation with instructing and responding roles: an inner, neural lineage induces the formation of an outer, border cell lineage (nBC) from the skin epithelium. Our results demonstrate that the neural lineage is necessary and sufficient to generate nBCs highlighting self-organisation principles at the level of the entire embryo. We hypothesise that induction of surrounding tissues plays a major role during the establishment of vertebrate stem cell niches. PMID:28950935

iPSC-derived cancer stem cells provide a model of tumor vasculature

PubMed Central

Prieto-Vila, Marta; Yan, Ting; Calle, Anna Sanchez; Nair, Neha; Hurley, Laura; Kasai, Tomonari; Kakuta, Hiroki; Masuda, Junko; Murakami, Hiroshi; Mizutani, Akifumi; Seno, Masaharu

2016-01-01

To grow beyond a size of approximately 1-2 mm3, tumor cells activate many processes to develop blood vasculature. Growing evidences indicate that the formation of the tumor vascular network is very complex, and is not restricted to angiogenesis. Cancer cell-derived tumor vasculatures have been recently described. Among them, endothelial differentiation of tumor cells have been directly related to cancer stem cells, which are cells within a tumor that possess the capacity to self-renew, and to exhibit multipotential heterogeneous lineages of cancer cells. Vasculogenic mimicry has been described to be formed by cancer cells expressing stemness markers. Thus, cancer stem cells have been proposed to contribute to vasculogenic mimicry, though its relation is yet to be clarified. Here, we analyzed the tumor vasculature by using a model of mouse cancer stem cells, miPS-LLCcm cells, which we have previously established from mouse induced pluripotent stem cells and we introduced the DsRed gene in miPS-LLCcm to trace them in vivo. Various features of vasculature were evaluated in ovo, in vitro, and in vivo. The tumors formed in allograft nude mice exhibited angiogenesis in chick chorioallantoic membrane assay. In those tumors, along with penetrated host endothelial vessels, we detected endothelial differentiation from cancer stem cells and formation of vasculogenic mimicry. The angiogenic factors such as VEGF-A and FGF2 were expressed predominantly in the cancer stem cells subpopulation of miPS-LLCcm cells. Our results suggested that cancer stem cells play key roles in not only the recruitment of host endothelial vessels into tumor, but also in maturation of endothelial linage of cancer stem cell’s progenies. Furthermore, the undifferentiated subpopulation of the miPS-LLCcm participates directly in the vasculogenic mimicry formation. Collectively, we show that miPS-LLCcm cells have advantages to further study tumor vasculature and to develop novel targeting strategies in the future. PMID:27725898

Stem cells in pharmaceutical biotechnology.

PubMed

Zuba-Surma, Ewa K; Józkowicz, Alicja; Dulak, Józef

2011-11-01

Multiple populations of stem cells have been indicated to potentially participate in regeneration of injured organs. Especially, embryonic stem cells (ESC) and recently inducible pluripotent stem cells (iPS) receive a marked attention from scientists and clinicians for regenerative medicine because of their high proliferative and differentiation capacities. Despite that ESC and iPS cells are expected to give rise into multiple regenerative applications when their side effects are overcame during appropriate preparation procedures, in fact their most recent application of human ESC may, however, reside in their use as a tool in drug development and disease modeling. This review focuses on the applications of stem cells in pharmaceutical biotechnology. We discuss possible relevance of pluripotent cell stem populations in developing physiological models for any human tissue cell type useful for pharmacological, metabolic and toxicity evaluation necessary in the earliest steps of drug development. The present models applied for preclinical drug testing consist of primary cells or immortalized cell lines that show limitations in terms of accessibility or relevance to their in vivo counterparts. The availability of renewable human cells with functional similarities to their in vivo counterparts is the first landmark for a new generation of cell-based assays. We discuss the approaches for using stem cells as valuable physiological targets of drug activity which may increase the strength of target validation and efficacy potentially resulting in introducing new safer remedies into clinical trials and the marketplace. Moreover, we discuss the possible applications of stem cells for elucidating mechanisms of disease pathogenesis. The knowledge about the mechanisms governing the development and progression of multitude disorders which would come from the cellular models established based on stem cells, may give rise to new therapeutical strategies for such diseases. All together, the applications of various cell types derived from patient specific pluripotent stem cells may lead to targeted drug and cellular therapies for certain individuals.

Early Prognostic Value of Monitoring Serum Free Light Chain in Patients with Multiple Myeloma Undergoing Autologous Stem Cell Transplantation.

PubMed

Özkurt, Zübeyde Nur; Sucak, Gülsan Türköz; Akı, Şahika Zeynep; Yağcı, Münci; Haznedar, Rauf

2017-03-16

We hypothesized the levels of free light chains obtained before and after autologous stem cell transplantation can be useful in predicting transplantation outcome. We analyzed 70 multiple myeloma patients. Abnormal free light chain ratios before stem cell transplantation were found to be associated early progression, although without any impact on overall survival. At day +30, the normalization of levels of involved free light chain related with early progression. According to these results almost one-third reduction of free light chain levels can predict favorable prognosis after autologous stem cell transplantation.

OVCAR-3 Spheroid-Derived Cells Display Distinct Metabolic Profiles

PubMed Central

Vermeersch, Kathleen A.; Wang, Lijuan; Mezencev, Roman; McDonald, John F.; Styczynski, Mark P.

2015-01-01

Introduction Recently, multicellular spheroids were isolated from a well-established epithelial ovarian cancer cell line, OVCAR-3, and were propagated in vitro. These spheroid-derived cells displayed numerous hallmarks of cancer stem cells, which are chemo- and radioresistant cells thought to be a significant cause of cancer recurrence and resultant mortality. Gene set enrichment analysis of expression data from the OVCAR-3 cells and the spheroid-derived putative cancer stem cells identified several metabolic pathways enriched in differentially expressed genes. Before this, there had been little previous knowledge or investigation of systems-scale metabolic differences between cancer cells and cancer stem cells, and no knowledge of such differences in ovarian cancer stem cells. Methods To determine if there were substantial metabolic changes corresponding with these transcriptional differences, we used two-dimensional gas chromatography coupled to mass spectrometry to measure the metabolite profiles of the two cell lines. Results These two cell lines exhibited significant metabolic differences in both intracellular and extracellular metabolite measurements. Principal components analysis, an unsupervised dimensional reduction technique, showed complete separation between the two cell types based on their metabolite profiles. Pathway analysis of intracellular metabolomics data revealed close overlap with metabolic pathways identified from gene expression data, with four out of six pathways found enriched in gene-level analysis also enriched in metabolite-level analysis. Some of those pathways contained multiple metabolites that were individually statistically significantly different between the two cell lines, with one of the most broadly and consistently different pathways, arginine and proline metabolism, suggesting an interesting hypothesis about cancerous and stem-like metabolic phenotypes in this pair of cell lines. Conclusions Overall, we demonstrate for the first time that metabolism in an ovarian cancer stem cell line is distinct from that of more differentiated isogenic cancer cells, supporting the potential importance of metabolism in the differences between cancer cells and cancer stem cells. PMID:25688563

Characterization of Cancer Stem-Like Cells Derived from Mouse Induced Pluripotent Stem Cells Transformed by Tumor-Derived Extracellular Vesicles

PubMed Central

Yan, Ting; Mizutani, Akifumi; Chen, Ling; Takaki, Mai; Hiramoto, Yuki; Matsuda, Shuichi; Shigehiro, Tsukasa; Kasai, Tomonari; Kudoh, Takayuki; Murakami, Hiroshi; Masuda, Junko; Hendrix, Mary J. C.; Strizzi, Luigi; Salomon, David S.; Fu, Li; Seno, Masaharu

2014-01-01

Several studies have shown that cancer niche can perform an active role in the regulation of tumor cell maintenance and progression through extracellular vesicles-based intercellular communication. However, it has not been reported whether this vesicle-mediated communication affects the malignant transformation of normal stem cells/progenitors. We have previously reported that the conditioned medium derived from the mouse Lewis Lung Carcinoma (LLC) cell line can convert mouse induced pluripotent stem cells (miPSCs) into cancer stem cells (CSCs), indicating that normal stem cells when placed in an aberrant microenvironment can give rise to functionally active CSCs. Here, we focused on the contribution of tumor-derived extracellular vesicles (tEVs) that are secreted from LLC cells to induce the transformation of miPSCs into CSCs. We isolated tEVs from the conditioned medium of LLC cells, and then the differentiating miPSCs were exposed to tEVs for 4 weeks. The resultant tEV treated cells (miPS-LLCev) expressed Nanog and Oct3/4 proteins comparable to miPSCs. The frequency of sphere formation of the miPS-LLCev cells in suspension culture indicated that the self-renewal capacity of the miPS-LLCev cells was significant. When the miPS-LLCev cells were subcutaneously transplanted into Balb/c nude mice, malignant liposarcomas with extensive angiogenesis developed. miPS-LLCevPT and miPS-LLCevDT, the cells established from primary site and disseminated liposarcomas, respectively, showed their capacities to self-renew and differentiate into adipocytes and endothelial cells. Moreover, we confirmed the secondary liposarcoma development when these cells were transplanted. Taken together, these results indicate that miPS-LLCev cells possess CSC properties. Thus, our current study provides the first evidence that tEVs have the potential to induce CSC properties in normal tissue stem cells/progenitors. PMID:25057308

The mechanics of gravitropic bending in leafy dicot stems

NASA Technical Reports Server (NTRS)

Salisbury, F. B.; Mueller, W. J.; Blotter, P. T.; Harris, C. S.; White, R. G.; Gillespie, L. S.; Sliwinski, J. E.

1982-01-01

The mechanism of the gravitropic bending in stems of the cocklebur and castor bean are investigated. The results of these experiments demonstrate the quick stopping of growth and the increased tensions on the upper layer of a horizontal stem. It is suggested that bending apparently occurs as the resistance of the upper surface layers is extended to the inner cells below. A model of stem bending is developed which can explain the asymmetry of the stem-cell response.

Cryopreservation of Hair-Follicle Associated Pluripotent (HAP) Stem Cells Maintains Differentiation and Hair-Growth Potential.

PubMed

Hoffman, Robert M; Kajiura, Satoshi; Cao, Wenluo; Liu, Fang; Amoh, Yasuyuki

2016-01-01

Hair follicles contain nestin-expressing pluripotent stem cells which originate above the bulge area of the follicle, below the sebaceous gland. We have termed these cells hair follicle-associated pluripotent (HAP) stem cells. We have established efficient cryopreservation methods of the hair follicle that maintain the pluripotency of HAP stem cells as well as hair growth. We cryopreserved the whole hair follicle by slow-rate cooling in TC-Protector medium or in DMSO-containing medium and storage in liquid nitrogen or at -80 °C. After thawing and culture of the cryopreserved whisker follicles, growing HAP stem cells formed hair spheres. The hair spheres contained cells that differentiated to neurons, glial cells, and other cell types. The hair spheres derived from slow-cooling cryopreserved hair follicles were as pluripotent as hair spheres from fresh hair follicles. We have also previously demonstrated that cryopreserved mouse whisker hair follicles maintain their hair-growth potential. DMSO better cryopreserved mouse whisker follicles compared to glycerol. DMSO-cryopreserved hair follicles also maintained the HAP stem cells, evidenced by P75 ntr expression. Subcutaneous transplantation of DMSO-cryopreserved hair follicles in nude mice resulted in extensive hair fiber growth over 8 weeks, indicating the functional recovery of hair-shaft growth of cryopreserved hair follicles. HAP stem cells can be used for nerve and spinal-cord repair. This biobanking of hair follicles can allow each patient the potential for their own stem cell use for regenerative medicine or hair transplantation.

Hematopoietic stem cell loss and hematopoietic failure in severe aplastic anemia is driven by macrophages and aberrant podoplanin expression.

PubMed

McCabe, Amanda; Smith, Julianne N P; Costello, Angelica; Maloney, Jackson; Katikaneni, Divya; MacNamara, Katherine C

2018-05-17

Severe aplastic anemia results from profound hematopoietic stem cell loss. T cells and interferon gamma have long been associated with severe aplastic anemia, yet the underlying mechanisms driving hematopoietic stem cell loss remain unknown. Using a mouse model of severe aplastic anemia, we demonstrate that interferon gamma-dependent hematopoietic stem cell loss required macrophages. Interferon gamma was necessary for bone marrow macrophage persistence, despite loss of other myeloid cells and hematopoietic stem cells. Depleting macrophages or abrogating interferon gamma signaling specifically in macrophages did not impair T cell activation or interferon gamma production in the bone marrow but rescued hematopoietic stem cells and reduced mortality. Thus, macrophages are not required for induction of interferon gamma in severe aplastic anemia and rather act as sensors of interferon gamma. Macrophage depletion rescued thrombocytopenia, increased bone marrow megakaryocytes, preserved platelet-primed stem cells, and increased the platelet-repopulating capacity of transplanted hematopoietic stem cells. In addition to the hematopoietic effects, severe aplastic anemia induced loss of non-hematopoietic stromal populations, including podoplanin-positive stromal cells. However, a subset of podoplanin-positive macrophages was increased during disease, and blockade of podoplanin in mice was sufficient to rescue disease. Our data further our understanding of disease pathogenesis demonstrating a novel role for macrophages as sensors of interferon gamma, thus illustrating an important role for the microenvironment in pathogenesis of severe aplastic anemia. Copyright © 2018, Ferrata Storti Foundation.

Recent advances in acute myeloid leukemia stem cell biology.

PubMed

Horton, Sarah J; Huntly, Brian J P

2012-07-01

The existence of cancer stem cells has long been postulated, but was proven less than 20 years ago following the demonstration that only a small sub-fraction of leukemic cells from acute myeloid leukemia patients were able to propagate the disease in xenografts. These cells were termed leukemic stem cells since they exist at the apex of a loose hierarchy, possess extensive self-renewal and the ability to undergo limited differentiation into leukemic blasts. Acute myeloid leukemia is a heterogeneous condition at both the phenotypic and molecular level with a variety of distinct genetic alterations giving rise to the disease. Recent studies have highlighted that this heterogeneity extends to the leukemic stem cell, with this dynamic compartment evolving to overcome various selection pressures imposed upon it during disease progression. The result is a complex situation in which multiple pools of leukemic stem cells may exist within individual patients which differ both phenotypically and molecularly. Since leukemic stem cells are thought to be resistant to current chemotherapeutic regimens and mediate disease relapse, their study also has potentially profound clinical implications. Numerous studies have generated important recent advances in the field, including the identification of novel leukemic stem cell-specific cell surface antigens and gene expression signatures. These tools will no doubt prove invaluable for the rational design of targeted therapies in the future.

The continued promise of stem cell therapy in regenerative medicine.

PubMed

Eve, David J

2011-12-01

The use of stem cells is galvanizing regenerative medicine research. An analysis of recent trends as typified by articles published between 2009 and 2010 in the journals Cell Transplantation--The Regenerative Medicine Journal and Medical Science Monitor demonstrate the increasing importance of stem cell research as being on the cutting edge of regenerative medicine research. The analysis revealed an even split between transplantation and non-transplantation studies, showing that both the applicability and general research is being pursued. New methods and tissue engineering are also highly important components of regenerative medicine as demonstrated by a number of the stem cell studies being involved with either ex vivo manipulation, or cotransplantation with other cells or biomaterials. This suggests that the best results may be achieved with adjuvant therapies. The non-transplantation studies were more focused on manipulation of transplantable agents including cells and scaffold systems, as well as the use of medicines and dietary supplements. The further elucidation of disease mechanisms was a major contribution. This analysis suggests that regenerative medicine is proceeding at a rapid pace and the next few years should be of considerable interest with the initial results of pioneering stem cell therapies being announced.

Mathematical modelling of phenotypic plasticity and conversion to a stem-cell state under hypoxia

NASA Astrophysics Data System (ADS)

Dhawan, Andrew; Madani Tonekaboni, Seyed Ali; Taube, Joseph H.; Hu, Stephen; Sphyris, Nathalie; Mani, Sendurai A.; Kohandel, Mohammad

2016-02-01

Hypoxia, or oxygen deficiency, is known to be associated with breast tumour progression, resistance to conventional therapies and poor clinical prognosis. The epithelial-mesenchymal transition (EMT) is a process that confers invasive and migratory capabilities as well as stem cell properties to carcinoma cells thus promoting metastatic progression. In this work, we examined the impact of hypoxia on EMT-associated cancer stem cell (CSC) properties, by culturing transformed human mammary epithelial cells under normoxic and hypoxic conditions, and applying in silico mathematical modelling to simulate the impact of hypoxia on the acquisition of CSC attributes and the transitions between differentiated and stem-like states. Our results indicate that both the heterogeneity and the plasticity of the transformed cell population are enhanced by exposure to hypoxia, resulting in a shift towards a more stem-like population with increased EMT features. Our findings are further reinforced by gene expression analyses demonstrating the upregulation of EMT-related genes, as well as genes associated with therapy resistance, in hypoxic cells compared to normoxic counterparts. In conclusion, we demonstrate that mathematical modelling can be used to simulate the role of hypoxia as a key contributor to the plasticity and heterogeneity of transformed human mammary epithelial cells.

Biomimetic extracellular matrix mediated somatic stem cell differentiation: applications in dental pulp tissue regeneration

PubMed Central

Ravindran, Sriram; George, Anne

2015-01-01

Dental caries is one of the most widely prevalent infectious diseases in the world. It affects more than half of the world's population. The current treatment for necrotic dental pulp tissue arising from dental caries is root canal therapy. This treatment results in loss of tooth sensitivity and vitality making it prone for secondary infections. Over the past decade, several tissue-engineering approaches have attempted regeneration of the dental pulp tissue. Although several studies have highlighted the potential of dental stem cells, none have transitioned into a clinical setting owing to limited availability of dental stem cells and the need for growth factor delivery systems. Our strategy is to utilize the intact ECM of pulp cells to drive lineage specific differentiation of bone marrow derived mesenchymal stem cells. From a clinical perspective, pulp ECM scaffolds can be generated using cell lines and patient specific somatic stem cells can be used for regeneration. Our published results have shown the feasibility of using pulp ECM scaffolds for odontogenic differentiation of non-dental mesenchymal cells. This focused review discusses the issues surrounding dental pulp tissue regeneration and the potential of our strategy to overcome these issues. PMID:25954205

Endogenous Stem Cells Were Recruited by Defocused Low-Energy Shock Wave in Treating Diabetic Bladder Dysfunction.

PubMed

Jin, Yang; Xu, Lina; Zhao, Yong; Wang, Muwen; Jin, Xunbo; Zhang, Haiyang

2017-04-01

Defocused low-energy shock wave (DLSW) has been shown effects on activating mesenchymal stromal cells (MSCs) in vitro. In this study, recruitment of endogenous stem cells was firstly examined as an important pathway during the healing process of diabetic bladder dysfunction (DBD) treated by DLSW in vivo. Neonatal rats received intraperitoneal injection of 5-ethynyl-2-deoxyuridine (EdU) and then DBD rat model was created by injecting streptozotocin. Four weeks later, DLSW treatment was performed. Afterward, their tissues were examined by histology. Meanwhile, adipose tissue-derived stem cells (ADSCs) were treated by DLSW in vitro. Results showed DLSW ameliorated voiding function of diabetic rats by recruiting EdU + Stro-1 + CD34 - endogenous stem cells to release abundant nerve growth factor (NGF) and vascular endothelial growth factor (VEGF). Some EdU + cells overlapped with staining of smooth muscle actin. After DLSW treatment, ADSCs showed higher migration ability, higher expression level of stromal cell-derived factor-1 and secreted more NGF and VEGF. In conclusion, DLSW could ameliorate DBD by recruiting endogenous stem cells. Beneficial effects were mediated by secreting NGF and VEGF, resulting into improved innervation and vascularization in bladder.

Hematopoietic stem cell engineering at a crossroads

PubMed Central

Rivière, Isabelle; Dunbar, Cynthia E.

2012-01-01

The genetic engineering of hematopoietic stem cells is the basis for potentially treating a large array of hereditary and acquired diseases, and stands as the paradigm for stem cell engineering in general. Recent clinical reports support the formidable promise of this approach but also highlight the limitations of the technologies used to date, which have on occasion resulted in clonal expansion, myelodysplasia, or leukemogenesis. New research directions, predicated on improved vector designs, targeted gene delivery or the therapeutic use of pluripotent stem cells, herald the advent of safer and more effective hematopoietic stem cell therapies that may transform medical practice. In this review, we place these recent advances in perspective, emphasizing the solutions emerging from a wave of new technologies and highlighting the challenges that lie ahead. PMID:22096239

Recurrent genomic instability of chromosome 1q in neural derivatives of human embryonic stem cells

PubMed Central

Varela, Christine; Denis, Jérôme Alexandre; Polentes, Jérôme; Feyeux, Maxime; Aubert, Sophie; Champon, Benoite; Piétu, Geneviève; Peschanski, Marc; Lefort, Nathalie

2012-01-01

Human pluripotent stem cells offer a limitless source of cells for regenerative medicine. Neural derivatives of human embryonic stem cells (hESCs) are currently being used for cell therapy in 3 clinical trials. However, hESCs are prone to genomic instability, which could limit their clinical utility. Here, we report that neural differentiation of hESCs systematically produced a neural stem cell population that could be propagated for more than 50 passages without entering senescence; this was true for all 6 hESC lines tested. The apparent spontaneous loss of evolution toward normal senescence of somatic cells was associated with a jumping translocation of chromosome 1q. This chromosomal defect has previously been associated with hematologic malignancies and pediatric brain tumors with poor clinical outcome. Neural stem cells carrying the 1q defect implanted into the brains of rats failed to integrate and expand, whereas normal cells engrafted. Our results call for additional quality controls to be implemented to ensure genomic integrity not only of undifferentiated pluripotent stem cells, but also of hESC derivatives that form cell therapy end products, particularly neural lines. PMID:22269325

The maintenance of pluripotency following laser direct-write of mouse embryonic stem cells.

PubMed

Raof, Nurazhani Abdul; Schiele, Nathan R; Xie, Yubing; Chrisey, Douglas B; Corr, David T

2011-03-01

The ability to precisely pattern embryonic stem (ES) cells in vitro into predefined arrays/geometries may allow for the recreation of a stem cell niche for better understanding of how cellular microenvironmental factors govern stem cell maintenance and differentiation. In this study, a new gelatin-based laser direct-write (LDW) technique was utilized to deposit mouse ES cells into defined arrays of spots, while maintaining stem cell pluripotency. Results obtained from these studies showed that ES cells were successfully printed into specific patterns and remained viable. Furthermore, ES cells retained the expression of Oct4 in nuclei after LDW, indicating that the laser energy did not affect their maintenance of an undifferentiated state. The differentiation potential of mouse ES cells after LDW was confirmed by their ability to form embryoid bodies (EBs) and to spontaneously become cell lineages representing all three germ layers, revealed by the expression of marker proteins of nestin (ectoderm), Myf-5 (mesoderm) and PDX-1 (endoderm), after 7 days of cultivation. Gelatin-based LDW provides a new avenue for stem cell patterning, with precision and control of the cellular microenvironment. Copyright © 2010 Elsevier Ltd. All rights reserved.

Stem Cell Therapy for the Inner Ear

PubMed Central

Okano, Takayuki

2012-01-01

In vertebrates, perception of sound, motion, and balance is mediated through mechanosensory hair cells located within the inner ear. In mammals, hair cells are only generated during a short period of embryonic development. As a result, loss of hair cells as a consequence of injury, disease, or genetic mutation, leads to permanent sensory deficits. At present, cochlear implantation is the only option for profound hearing loss. However, outcomes are still variable and even the best implant cannot provide the acuity of a biological ear. The recent emergence of stem cell technology has the potential to open new approaches for hair cell regeneration. The goal of this review is to summarize the current state of inner ear stem cell research from a viewpoint of its clinical application for inner ear disorders to illustrate how complementary studies have the potential to promote and refine stem cell therapies for inner ear diseases. The review initially discusses our current understanding of the genetic pathways that regulate hair cell formation from inner ear progenitors during normal development. Subsequent sections discuss the possible use of endogenous inner ear stem cells to induce repair as well as the initial studies aimed at transplanting stem cells into the ear. PMID:22514095

Bio-engineering inslulin-secreting cells from embryonic stem cells: a review of progress.

PubMed

Roche, E; Sepulcre, M P; Enseñat-Waser, R; Maestre, I; Reig, J A; Soria, B

2003-07-01

According to the Edmonton protocol, human islet transplantation can result in insulin independency for periods longer than 3 years. However, this therapy for type 1 diabetes is limited by the scarcity of cadaveric donors. Owing to the ability of embryonic stem cells to expand in vitro and differentiate into a variety of cell types, research has focused on ways to manipulate these cells to overcome this problem. It has been demonstrated that mouse embryonic stem cells can differentiate into insulin-containing cells, restoring normoglycaemia in diabetic mice. To this end, mouse embryonic stem cells were transfected with a DNA construct that provides resistance to neomycin under the control of the regulatory regions of the human insulin gene. However, this protocol has a very low efficiency, needing improvements for this technology to be transferred to human stem cells. Optimum protocols will be instrumental in the production of an unlimited source of cells that synthesise, store and release insulin in a physiological manner. The review focuses on the alternative source of tissue offered by embryonic stem cells for regenerative medicine in diabetes and some key points that should be considered in order for a definitive protocol for in vitro differentiation to be established.

Dependence of Corneal Stem/Progenitor Cells on Ocular Surface Innervation

PubMed Central

Ueno, Hiroki; Ferrari, Giulio; Hattori, Takaaki; Saban, Daniel R.; Katikireddy, Kishore R.; Chauhan, Sunil K.

2012-01-01

Purpose. Neurotrophic keratopathy (NK) is a corneal degeneration associated with corneal nerve dysfunction. It can cause corneal epithelial defects, stromal thinning, and perforation. However, it is not clear if and to which extent epithelial stem cells are affected in NK. The purpose of this study was to identify the relationship between corneolimbal epithelial progenitor/stem cells and sensory nerves using a denervated mouse model of NK. Methods. NK was induced in mice by electrocoagulation of the ophthalmic branch of the trigeminal nerve. The absence of corneal nerves was confirmed with β-III tubulin immunostaining and blink reflex test after 7 days. ATP-binding cassette subfamily G member 2 (ABCG2), p63, and hairy enhancer of split 1 (Hes1) were chosen as corneolimbal stem/progenitor cell markers and assessed in denervated mice versus controls by immunofluorescent microscopy and real-time PCR. In addition, corneolimbal stem/progenitor cells were detected as side population cells using flow cytometry, and colony-forming efficiency assay was performed to assess their function. Results. ABCG2, p63, and Hes1 immunostaining were significantly decreased in denervated eyes after 7 days. Similarly, the expression levels of ABCG2, p63, K15, Hes1, and N-cadherin transcripts were also significantly decreased in denervated eyes. Stem/progenitor cells measured as side population from NK mice were decreased by approximately 75% compared with normals. In addition, the authors found a significant (P = 0.038) reduction in colony-forming efficiency of stem/progenitor cells harvested from denervated eyes. Conclusions. Corneolimbal stem/progenitor cells are significantly reduced after depletion of sensory nerves. The data suggest a critical role of innervation in maintaining stem cells and/or the stem cell niche. PMID:22232434

Entropy, Ergodicity, and Stem Cell Multipotency

NASA Astrophysics Data System (ADS)

Ridden, Sonya J.; Chang, Hannah H.; Zygalakis, Konstantinos C.; MacArthur, Ben D.

2015-11-01

Populations of mammalian stem cells commonly exhibit considerable cell-cell variability. However, the functional role of this diversity is unclear. Here, we analyze expression fluctuations of the stem cell surface marker Sca1 in mouse hematopoietic progenitor cells using a simple stochastic model and find that the observed dynamics naturally lie close to a critical state, thereby producing a diverse population that is able to respond rapidly to environmental changes. We propose an information-theoretic interpretation of these results that views cellular multipotency as an instance of maximum entropy statistical inference.

MUC4 stabilizes HER2 expression and maintains the cancer stem cell population in ovarian cancer cells

PubMed Central

2011-01-01

Background Recent evidence has suggested that the capability of cancer to grow, propagate and relapse after therapy is dependent on a small subset of the cell population within the tumor, called cancer stem cells. Therefore, this subpopulation of cells needs to be targeted with different approaches by identification of unique stem-cell specific target antigens. One of the well known tumor antigens is the epithelial cell mucin MUC4, which is aberrantly expressed in ovarian cancer as compared to the normal ovary and plays a pivotal role in the aggressiveness and metastasis of ovarian cancer cells. In the present study, we aimed to analyze the cancer stem cell population in MUC4 overexpressed ovarian cancer cells. Methods MUC4 was ectopically overexpressed in SKOV3 ovarian cancer cells. Western blot analysis was performed for MUC4, HER2, CD133, ALDH1 and Shh expression in MUC4 overexpressed cells. Confocal analysis of MUC4, HER2 and CD133 was also done in the MUC4 overexpressed cells. CD133 and Hoechst33342 dye staining was used to analyze the cancer stem cell population via FACS method in SKOV3-MUC4 cells. Results MUC4 overexpressed SKOV3 cells showed an increased expression of HER2 compared to control cells. MUC4 overexpression leads to increased (0.1%) side population (SP) and CD133-positive cancer stem cells compared to the control cells. Interestingly, the tumor sphere type circular colony formation was observed only in the MUC4 overexpressed ovarian cancer cells. Furthermore, the cancer stem cell marker CD133 was expressed along with MUC4 in the isolated circular colonies as analyzed by both confocal and western blot analysis. HER2 and cancer stem cell specific marker ALDH1 along with Shh, a self-renewal marker, showed increased expression in the isolated circular colonies compared to MUC4-transfected cells. Conclusion These studies demonstrate that MUC4 overexpression leads to an enriched ovarian cancer stem cell population either directly or indirectly through HER2. In future, this study would be helpful for MUC4-directed therapy for the ovarian cancer stem cell population. PMID:21521521

Osteopontin attenuates aging-associated phenotypes of hematopoietic stem cells.

PubMed

Guidi, Novella; Sacma, Mehmet; Ständker, Ludger; Soller, Karin; Marka, Gina; Eiwen, Karina; Weiss, Johannes M; Kirchhoff, Frank; Weil, Tanja; Cancelas, Jose A; Florian, Maria Carolina; Geiger, Hartmut

2017-04-03

Upon aging, hematopoietic stem cells (HSCs) undergo changes in function and structure, including skewing to myeloid lineages, lower reconstitution potential and loss of protein polarity. While stem cell intrinsic mechanisms are known to contribute to HSC aging, little is known on whether age-related changes in the bone marrow niche regulate HSC aging. Upon aging, the expression of osteopontin (OPN) in the murine bone marrow stroma is reduced. Exposure of young HSCs to an OPN knockout niche results in a decrease in engraftment, an increase in long-term HSC frequency and loss of stem cell polarity. Exposure of aged HSCs to thrombin-cleaved OPN attenuates aging of old HSCs, resulting in increased engraftment, decreased HSC frequency, increased stem cell polarity and a restored balance of lymphoid and myeloid cells in peripheral blood. Thus, our data suggest a critical role for reduced stroma-derived OPN for HSC aging and identify thrombin-cleaved OPN as a novel niche informed therapeutic approach for ameliorating HSC phenotypes associated with aging. © 2017 The Authors. Published under the terms of the CC BY NC ND 4.0 license.

Restoring Ureagenesis in Hepatocytes by CRISPR/Cas9-mediated Genomic Addition to Arginase-deficient Induced Pluripotent Stem Cells.

PubMed

Lee, Patrick C; Truong, Brian; Vega-Crespo, Agustin; Gilmore, W Blake; Hermann, Kip; Angarita, Stephanie Ak; Tang, Jonathan K; Chang, Katherine M; Wininger, Austin E; Lam, Alex K; Schoenberg, Benjamen E; Cederbaum, Stephen D; Pyle, April D; Byrne, James A; Lipshutz, Gerald S

2016-11-29

Urea cycle disorders are incurable enzymopathies that affect nitrogen metabolism and typically lead to hyperammonemia. Arginase deficiency results from a mutation in Arg1, the enzyme regulating the final step of ureagenesis and typically results in developmental disabilities, seizures, spastic diplegia, and sometimes death. Current medical treatments for urea cycle disorders are only marginally effective, and for proximal disorders, liver transplantation is effective but limited by graft availability. Advances in human induced pluripotent stem cell research has allowed for the genetic modification of stem cells for potential cellular replacement therapies. In this study, we demonstrate a universally-applicable CRISPR/Cas9-based strategy utilizing exon 1 of the hypoxanthine-guanine phosphoribosyltransferase locus to genetically modify and restore arginase activity, and thus ureagenesis, in genetically distinct patient-specific human induced pluripotent stem cells and hepatocyte-like derivatives. Successful strategies restoring gene function in patient-specific human induced pluripotent stem cells may advance applications of genetically modified cell therapy to treat urea cycle and other inborn errors of metabolism.

Tracking stem cell migration and survival in brain injury: current approaches and future prospects.

PubMed

Darkazalli, Ali; Levenson, Cathy W

2012-10-01

In recent years, stem cell-mediated therapies have gained considerable ground as potential treatments for a wide variety of brain pathologies including traumatic brain injury, stroke and neurodegenerative diseases. Despite extensive preclinical studies, many of these therapies have not been fully translated into viable clinical approaches. This is partly due to our inability to reliably track and monitor transplanted stem cells longitudinally over long periods of time in vivo. In this review, we discuss the predominant histological cell tracing methodologies, such as immunohistochemistry, and fluorescent cellular dyes and proteins, and compare them to emerging cellular imaging technologies. We show that advances in magnetic resonance imaging (MRI) have resulted in opportunities to use this technology to further our understanding of stem cell characteristics and behaviors in vivo. While MRI may not completely replace conventional cell tracking methods in pre-clinical, mechanistic work, it is clear that it has the potential to function as a powerful diagnostic tool for tracking stem cell migration and survival as well as for evaluating the efficacy of stem cell-mediated therapies.

Stem cells therapy for ALS.

PubMed

Mazzini, Letizia; Vescovi, Angelo; Cantello, Roberto; Gelati, Maurizio; Vercelli, Alessandro

2016-01-01

Despite knowledge on the molecular basis of amyotrophic lateral sclerosis (ALS) having quickly progressed over the last few years, such discoveries have not yet translated into new therapeutics. With the advancement of stem cell technologies there is hope for stem cell therapeutics as novel treatments for ALS. We discuss in detail the therapeutic potential of different types of stem cells in preclinical and clinical works. Moreover, we address many open questions in clinical translation. SC therapy is a potentially promising new treatment for ALS and the need to better understand how to develop cell-based experimental treatments, and how to implement them in clinical trials, becomes more pressing. Mesenchymal stem cells and neural fetal stem cells have emerged as safe and potentially effective cell types, but there is a need to carry out appropriately designed experimental studies to verify their long-term safety and possibly efficacy. Moreover, the cost-benefit analysis of the results must take into account the quality of life of the patients as a major end point. It is our opinion that a multicenter international clinical program aime d at fine-tuning and coordinating transplantation procedures and protocols is mandatory.

Engineered stem cell mimics to enhance stroke recovery.

PubMed

George, Paul M; Oh, Byeongtaek; Dewi, Ruby; Hua, Thuy; Cai, Lei; Levinson, Alexa; Liang, Xibin; Krajina, Brad A; Bliss, Tonya M; Heilshorn, Sarah C; Steinberg, Gary K

2018-06-13

Currently, no medical therapies exist to augment stroke recovery. Stem cells are an intriguing treatment option being evaluated, but cell-based therapies have several challenges including developing a stable cell product with long term reproducibility. Since much of the improvement observed from cellular therapeutics is believed to result from trophic factors the stem cells release over time, biomaterials are well-positioned to deliver these important molecules in a similar fashion. Here we show that essential trophic factors secreted from stem cells can be effectively released from a multi-component hydrogel system into the post-stroke environment. Using our polymeric system to deliver VEGF-A and MMP-9, we improved recovery after stroke to an equivalent degree as observed with traditional stem cell treatment in a rodent model. While VEGF-A and MMP-9 have many unique mechanisms of action, connective tissue growth factor (CTGF) interacts with both VEGF-A and MMP-9. With our hydrogel system as well as with stem cell delivery, the CTGF pathway is shown to be downregulated with improved stroke recovery. Copyright © 2018 Elsevier Ltd. All rights reserved.

Canine Adipose-Derived Stem Cells: Purinergic Characterization and Neurogenic Potential for Therapeutic Applications.

PubMed

Roszek, Katarzyna; Makowska, Noemi; Czarnecka, Joanna; Porowińska, Dorota; Dąbrowski, Marcin; Danielewska, Justyna; Nowak, Wiesław

2017-01-01

The presented results evidence that canine adipose-derived stem cells (ADSCs) represent the premature population of stem cells with great biological potential and properties. ADCS are easy to obtain and culture, able to differentiate into the neurogenic lineage as well as it is easy to control their proliferation rate with nucleotides and nucleosides or analogues. We report that in vitro cultured canine ADSCs response to adenosine- and ATP-mediated stimulation. Differences in canine ADSCs and human mesenchymal stem cells in ecto-nucleotidase activity have been observed. The ecto-nucleotidase activity changes during ADSCs in vitro transdifferentiation into neurogenic lineage are fast and simple to analyze. Therefore, the simple analysis of ecto-enzymes activity allows for verification of the stem cells quality: their stemness or initiation of the differentiation process. The biological potential of the cells isolated from canine fat, as well as the good quality control of this cell culture, make them a promising tool for both experimental and therapeutic usage. J. Cell. Biochem. 118: 58-65, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Gene expression profiling of rat spermatogonia and Sertoli cells reveals signaling pathways from stem cells to niche and testicular cancer cells to surrounding stroma

PubMed Central

2011-01-01

Background Stem cells and their niches are studied in many systems, but mammalian germ stem cells (GSC) and their niches are still poorly understood. In rat testis, spermatogonia and undifferentiated Sertoli cells proliferate before puberty, but at puberty most spermatogonia enter spermatogenesis, and Sertoli cells differentiate to support this program. Thus, pre-pubertal spermatogonia might possess GSC potential and pre-pubertal Sertoli cells niche functions. We hypothesized that the different stem cell pools at pre-puberty and maturity provide a model for the identification of stem cell and niche-specific genes. We compared the transcript profiles of spermatogonia and Sertoli cells from pre-pubertal and pubertal rats and examined how these related to genes expressed in testicular cancers, which might originate from inappropriate communication between GSCs and Sertoli cells. Results The pre-pubertal spermatogonia-specific gene set comprised known stem cell and spermatogonial stem cell (SSC) markers. Similarly, the pre-pubertal Sertoli cell-specific gene set comprised known niche gene transcripts. A large fraction of these specifically enriched transcripts encoded trans-membrane, extra-cellular, and secreted proteins highlighting stem cell to niche communication. Comparing selective gene sets established in this study with published gene expression data of testicular cancers and their stroma, we identified sets expressed genes shared between testicular tumors and pre-pubertal spermatogonia, and tumor stroma and pre-pubertal Sertoli cells with statistic significance. Conclusions Our data suggest that SSC and their niche specifically express complementary factors for cell communication and that the same factors might be implicated in the communication between tumor cells and their micro-enviroment in testicular cancer. PMID:21232125

Human skeletal muscle-derived stem cells retain stem cell properties after expansion in myosphere culture

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wei, Yan; Department of Otolaryngology, Head and Neck Surgery, The Third Affiliated Hospital of Sun Yat-sen University, Guang Zhou; Li, Yuan

2011-04-15

Human skeletal muscle contains an accessible adult stem-cell compartment in which differentiated myofibers are maintained and replaced by a self-renewing stem cell pool. Previously, studies using mouse models have established a critical role for resident stem cells in skeletal muscle, but little is known about this paradigm in human muscle. Here, we report the reproducible isolation of a population of cells from human skeletal muscle that is able to proliferate for extended periods of time as floating clusters of rounded cells, termed 'myospheres' or myosphere-derived progenitor cells (MDPCs). The phenotypic characteristics and functional properties of these cells were determined usingmore » reverse transcription-polymerase chain reaction (RT-PCR), flow cytometry and immunocytochemistry. Our results showed that these cells are clonogenic, express skeletal progenitor cell markers Pax7, ALDH1, Myod, and Desmin and the stem cell markers Nanog, Sox2, and Oct3/4 significantly elevated over controls. They could be maintained proliferatively active in vitro for more than 20 weeks and passaged at least 18 times, despite an average donor-age of 63 years. Individual clones (4.2%) derived from single cells were successfully expanded showing clonogenic potential and sustained proliferation of a subpopulation in the myospheres. Myosphere-derived cells were capable of spontaneous differentiation into myotubes in differentiation media and into other mesodermal cell lineages in induction media. We demonstrate here that direct culture and expansion of stem cells from human skeletal muscle is straightforward and reproducible with the appropriate technique. These cells may provide a viable resource of adult stem cells for future therapies of disease affecting skeletal muscle or mesenchymal lineage derived cell types.« less

Physiologic oxygen concentration enhances the stem-like properties of CD133+ human glioblastoma cells in vitro.

PubMed

McCord, Amy M; Jamal, Muhammad; Shankavaram, Uma T; Shankavarum, Uma T; Lang, Frederick F; Camphausen, Kevin; Tofilon, Philip J

2009-04-01

In vitro investigations of tumor stem-like cells (TSC) isolated from human glioblastoma (GB) surgical specimens have been done primarily at an atmospheric oxygen level of 20%. To determine whether an oxygen level more consistent with in situ conditions affects their stem cell-like characteristics, we compared GB TSCs grown under conditions of 20% and 7% oxygen. Growing CD133(+) cells sorted from three GB neurosphere cultures at 7% O(2) reduced their doubling time and increased the self-renewal potential as reflected by clonogenicity. Furthermore, at 7% oxygen, the cultures exhibited an enhanced capacity to differentiate along both the glial and neuronal pathways. As compared with 20%, growth at 7% oxygen resulted in an increase in the expression levels of the neural stem cell markers CD133 and nestin as well as the stem cell markers Oct4 and Sox2. In addition, whereas hypoxia inducible factor 1alpha was not affected in CD133(+) TSCs grown at 7% O(2), hypoxia-inducible factor 2alpha was expressed at higher levels as compared with 20% oxygen. Gene expression profiles generated by microarray analysis revealed that reducing oxygen level to 7% resulted in the up-regulation and down-regulation of a significant number of genes, with more than 140 being commonly affected among the three CD133(+) cultures. Furthermore, Gene Ontology categories up-regulated at 7% oxygen included those associated with stem cells or GB TSCs. Thus, the data presented indicate that growth at the more physiologically relevant oxygen level of 7% enhances the stem cell-like phenotype of CD133(+) GB cells.

Cell culture density affects the stemness gene expression of adipose tissue-derived mesenchymal stem cells.

PubMed

Kim, Dae Seong; Lee, Myoung Woo; Lee, Tae-Hee; Sung, Ki Woong; Koo, Hong Hoe; Yoo, Keon Hee

2017-03-01

The results of clinical trials using mesenchymal stem cells (MSCs) are controversial due to the heterogeneity of human MSCs and differences in culture conditions. In this regard, it is important to identify gene expression patterns according to culture conditions, and to determine how the cells are expanded and when they should be clinically used. In the current study, stemness gene expression was investigated in adipose tissue-derived MSCs (AT-MSCs) harvested following culture at different densities. AT-MSCs were plated at a density of 200 or 5,000 cells/cm 2 . After 7 days of culture, stemness gene expression was examined by reverse transcription-quantitative polymerase chain reaction (RT-qPCR) analysis. The proliferation rate of AT-MSCs harvested at a low density (~50% confluent) was higher than that of AT-MSCs harvested at a high density (~90% confluent). Although there were differences in the expression levels of stemness gene, such as octamer-binding transcription factor 4, nanog homeobox ( Nanog ), SRY-box 2, Kruppel like factor 4, v-myc avian myelocytomatosis viral oncogene homolog ( c-Myc ), and lin-28 homolog A, in the AT-MSCs obtained from different donors, RT-qPCR analysis demonstrated differential gene expression patterns according to the cell culture density. Expression levels of stemness genes, particularly Nanog and c-Myc , were upregulated in AT-MSCs harvested at a low density (~50% confluent) in comparison to AT-MSCs from the same donor harvested at a high density (~90% confluent). These results imply that culture conditions, such as the cell density at harvesting, modulate the stemness gene expression and proliferation of MSCs.

Adipose-derived Stem Cells Stimulated with n-Butylidenephthalide Exhibit Therapeutic Effects in a Mouse Model of Parkinson's Disease.

PubMed

Chi, Kang; Fu, Ru-Huei; Huang, Yu-Chuen; Chen, Shih-Yin; Hsu, Ching-Ju; Lin, Shinn-Zong; Tu, Chi-Tang; Chang, Li-Hsun; Wu, Ping-An; Liu, Shih-Ping

2018-03-01

Parkinson's disease (PD) causes motor dysfunction and dopaminergic cell death. Drug treatments can effectively reduce symptoms but often cause unwanted side effects. Stem cell therapies using cell replacement or indirect beneficial secretomes have recently emerged as potential therapeutic strategies. Although various types of stem cells have been proposed as possible candidates, adipose-derived stem cells (ADSCs) are easily obtainable, more abundant, less ethically disputed, and able to differentiate into multiple cell lineages. However, treatment of PD using adult stem cells is known to be less efficacious than neuron or embryonic stem cell transplantation. Therefore, improved therapies are urgently needed. n-Butylidenephthalide (BP), which is extracted from Angelica sinensis, has been shown to have anti-inflammatory and neuroprotective effects. Indeed, we previously demonstrated that BP treatment of ADSCs enhances the expression of neurogenesis and homing factors such as nuclear receptor related 1 protein, stromal-derived factor 1, and brain-derived neurotrophic factor. In the present study, we examined the ability of BP-pretreated ADSC transplantation to improve PD motor symptoms and protect dopamine neurons in a mouse model of PD. We evaluated the results using neuronal behavior tests such as beam walking, rotarod, and locomotor activity tests. ADSCs with or without BP pretreatment were transplanted into the striatum. Our findings demonstrated that ADSC transplantation improved motor abilities with varied efficacies and that BP stimulation improved the therapeutic effects of transplantation. Dopaminergic cell numbers returned to normal in ADSC-transplanted mice after 22 d. In summary, stimulating ADSCs with BP improved PD recovery efficiency. Thus, our results provide important new strategies to improve stem cell therapies for neurodegenerative diseases in future studies.

Parameter estimation for an immortal model of colonic stem cell division using approximate Bayesian computation.

PubMed

Walters, Kevin

2012-08-07

In this paper we use approximate Bayesian computation to estimate the parameters in an immortal model of colonic stem cell division. We base the inferences on the observed DNA methylation patterns of cells sampled from the human colon. Utilising DNA methylation patterns as a form of molecular clock is an emerging area of research and has been used in several studies investigating colonic stem cell turnover. There is much debate concerning the two competing models of stem cell turnover: the symmetric (immortal) and asymmetric models. Early simulation studies concluded that the observed methylation data were not consistent with the immortal model. A later modified version of the immortal model that included preferential strand segregation was subsequently shown to be consistent with the same methylation data. Most of this earlier work assumes site independent methylation models that do not take account of the known processivity of methyltransferases whilst other work does not take into account the methylation errors that occur in differentiated cells. This paper addresses both of these issues for the immortal model and demonstrates that approximate Bayesian computation provides accurate estimates of the parameters in this neighbour-dependent model of methylation error rates. The results indicate that if colonic stem cells divide asymmetrically then colon stem cell niches are maintained by more than 8 stem cells. Results also indicate the possibility of preferential strand segregation and provide clear evidence against a site-independent model for methylation errors. In addition, algebraic expressions for some of the summary statistics used in the approximate Bayesian computation (that allow for the additional variation arising from cell division in differentiated cells) are derived and their utility discussed. Copyright © 2012 Elsevier Ltd. All rights reserved.

CD44 staining of cancer stem-like cells is influenced by down-regulation of CD44 variant isoforms and up-regulation of the standard CD44 isoform in the population of cells that have undergone epithelial-to-mesenchymal transition.

PubMed

Biddle, Adrian; Gammon, Luke; Fazil, Bilal; Mackenzie, Ian C

2013-01-01

CD44 is commonly used as a cell surface marker of cancer stem-like cells in epithelial tumours, and we have previously demonstrated the existence of two different CD44(high) cancer stem-like cell populations in squamous cell carcinoma, one having undergone epithelial-to-mesenchymal transition and the other maintaining an epithelial phenotype. Alternative splicing of CD44 variant exons generates a great many isoforms, and it is not known which isoforms are expressed on the surface of the two different cancer stem-like cell phenotypes. Here, we demonstrate that cancer stem-like cells with an epithelial phenotype predominantly express isoforms containing the variant exons, whereas the cancer stem-like cells that have undergone an epithelial-to-mesenchymal transition down-regulate these variant isoforms and up-regulate expression of the standard CD44 isoform that contains no variant exons. In addition, we find that enzymatic treatments used to dissociate cells from tissue culture or fresh tumour specimens cause destruction of variant CD44 isoforms at the cell surface whereas expression of the standard CD44 isoform is preserved. This results in enrichment within the CD44(high) population of cancer stem-like cells that have undergone an epithelial-to-mesenchymal transition and depletion from the CD44(high) population of cancer stem-like cells that maintain an epithelial phenotype, and therefore greatly effects the characteristics of any cancer stem-like cell population isolated based on expression of CD44. As well as effecting the CD44(high) population, enzymatic treatment also reduces the percentage of the total epithelial cancer cell population staining CD44-positive, with potential implications for studies that aim to use CD44-positive staining as a prognostic indicator. Analyses of the properties of cancer stem-like cells are largely dependent on the ability to accurately identify and assay these populations. It is therefore critical that consideration be given to use of multiple cancer stem-like cell markers and suitable procedures for cell isolation in order that the correct populations are assayed.

Efficient femtosecond driven SOX 17 delivery into mouse embryonic stem cells: differentiation studies

NASA Astrophysics Data System (ADS)

Thobakgale, Lebogang; Manoto, Sello Lebohang; Lemboumba, Satuurnin Ombinda; Maaza, Malik; Mthunzi-Kufa, Patience

2017-02-01

Embryonic stem cells have great promise in regenerative medicine because of their ability to self-renew and differentiate into various cell types. Delivery of therapeutic genes into cells has already been achieved using of chemical agents and viral vectors with high transfection efficiencies. However, these methods have also been documented as toxic and in the latter case they can cause latent cell infections. In this study we use femtosecond laser pulses to optically deliver genetic material in mouse embryonic stem cells. Femtosecond laser pulses in contrast to the conventional approach, minimises the risk of unwanted side effects because photons are used to create transient pores on the membrane which allow free entry of molecules with no need for delivery agents. Using an Olympus microscope, fluorescence imaging of the samples post irradiation was performed and decreased expression of stage specific embryonic antigen one (SSEA-1) consistent with on-going cellular differentiation was observed. Our results also show that femtosecond laser pulses were effective in delivering SOX 17 plasmid DNA (pSOX17) which resulted in the differentiation of mouse embryonic stem cells into endoderm cells. We thus concluded that laser transfection of stem cells for the purpose of differentiation, holds potential for applications in tissue engineering as a method of generating new cell lines.

Functional genomic characterization of neoblast-like stem cells in larval Schistosoma mansoni

PubMed Central

Wang, Bo; Collins, James J; Newmark, Phillip A

2013-01-01

Schistosomes infect hundreds of millions of people in the developing world. Transmission of these parasites relies on a stem cell-driven, clonal expansion of larvae inside a molluscan intermediate host. How this novel asexual reproductive strategy relates to current models of stem cell maintenance and germline specification is unclear. Here, we demonstrate that this proliferative larval cell population (germinal cells) shares some molecular signatures with stem cells from diverse organisms, in particular neoblasts of planarians (free-living relatives of schistosomes). We identify two distinct germinal cell lineages that differ in their proliferation kinetics and expression of a nanos ortholog. We show that a vasa/PL10 homolog is required for proliferation and maintenance of both populations, whereas argonaute2 and a fibroblast growth factor receptor-encoding gene are required only for nanos-negative cells. Our results suggest that an ancient stem cell-based developmental program may have enabled the evolution of the complex life cycle of parasitic flatworms. DOI: http://dx.doi.org/10.7554/eLife.00768.001 PMID:23908765

Estimation of the effectiveness ratio (α/β) for resistant cancer cells in U87MG human glioblastoma.

PubMed

Marmolejo-León, Perla; Azorín-Vega, Erika Patricia; Jiménez-Mancilla, Nallely; Mendoza-Nava, Héctor Javier; Mitsoura, Eleni; Pineda, Benjamín; Torres-García, Eugenio

2018-01-11

Glioblastoma contains self-renewing, tumorigenic cancer stem-like cells that contribute to tumor initiation and therapeutic resistance. The aim of this research was to estimate and compare the effectiveness ratio (α/β) of stem-like cells and differentiated glioma cells derived from the U87MG glioblastoma cell line. Cell survival experiments were obtained in a dose range of 0-20 Gy (13.52 ± 0.09 Gy/h) as a hyperfractionationated accelerated radiotherapy scheme. Biochemical characterization of the post-irradiated cells was performed by flow cytometry analysis and the percentage of stem-like cells that resisted irradiation was determined by the CD133 expression. Results showed that U87MG stem-like cells are highly proliferative and more radioresistant than the U87MG adherent group (with a lesser stem-like character), this in association with the calculated α/β ratio of 17 and 14.1, respectively. Copyright © 2018 Elsevier Ltd. All rights reserved.

Stem cell senescence drives age-attenuated induction of pituitary tumours in mouse models of paediatric craniopharyngioma.

PubMed

Mario Gonzalez-Meljem, Jose; Haston, Scott; Carreno, Gabriela; Apps, John R; Pozzi, Sara; Stache, Christina; Kaushal, Grace; Virasami, Alex; Panousopoulos, Leonidas; Neda Mousavy-Gharavy, Seyedeh; Guerrero, Ana; Rashid, Mamunur; Jani, Nital; Goding, Colin R; Jacques, Thomas S; Adams, David J; Gil, Jesus; Andoniadou, Cynthia L; Martinez-Barbera, Juan Pedro

2017-11-28

Senescent cells may promote tumour progression through the activation of a senescence-associated secretory phenotype (SASP), whether these cells are capable of initiating tumourigenesis in vivo is not known. Expression of oncogenic β-catenin in Sox2+ young adult pituitary stem cells leads to formation of clusters of stem cells and induction of tumours resembling human adamantinomatous craniopharyngioma (ACP), derived from Sox2- cells in a paracrine manner. Here, we uncover the mechanisms underlying this paracrine tumourigenesis. We show that expression of oncogenic β-catenin in Hesx1+ embryonic precursors also results in stem cell clusters and paracrine tumours. We reveal that human and mouse clusters are analogous and share a common signature of senescence and SASP. Finally, we show that mice with reduced senescence and SASP responses exhibit decreased tumour-inducing potential. Together, we provide evidence that senescence and a stem cell-associated SASP drive cell transformation and tumour initiation in vivo in an age-dependent fashion.

Concise reviews: cancer stem cells: from concept to cure.

PubMed

Matchett, K B; Lappin, T R

2014-10-01

In 1953, noting a remarkable consistency between the agents causing mutations and those associated with cancer, Carl Nordling, a Finnish-born architect, proposed that cancer results from an accumulation of genetic mutations. It is now generally accepted that inherited mutations and environmental carcinogens can lead to the development of premalignant clones. After further mutations, one cell reaches a critical state which confers a survival or growth advantage over normal cells. Such cells have the ability to initiate a malignant tumour. They share many of the features of normal stem cells, including the capacity for self-renewal and differentiation, and are widely termed cancer stem cells (CSCs). Although CSCs have been well characterized in hematological malignancies, their existence in some other tissues has been questioned. Here, we review recent work in which stem cells and stem cell-like cells have been used to investigate the pathogenesis of cancer and potential anticancer treatment strategies, in the context of both hematological and somatic tissue disease. © 2014 AlphaMed Press.

The suture provides a niche for mesenchymal stem cells of craniofacial bones

PubMed Central

Zhao, Hu; Feng, Jifan; Ho, Thach-Vu; Grimes, Weston; Urata, Mark; Chai, Yang

2015-01-01

Bone tissue undergoes constant turnover supported by stem cells. Recent studies showed that perivascular mesenchymal stem cells (MSCs) contribute to the turnover of long bones. Craniofacial bones are flat bones derived from a different embryonic origin than the long bones. The identity and regulating niche for craniofacial bone MSCs remain unknown. Here, we identify Gli1+ cells within the suture mesenchyme as the major MSC population for craniofacial bones. They are not associated with vasculature, give rise to all craniofacial bones in the adult and are activated during injury repair. Gli1+ cells are typical MSCs in vitro. Ablation of Gli1+ cells leads to craniosynostosis and arrest of skull growth, indicating these cells are an indispensible stem cell population. Twist1+/− mice with craniosynostosis show reduced Gli1+ MSCs in sutures, suggesting that craniosynostosis may result from diminished suture stem cells. Our study indicates that craniofacial sutures provide a unique niche for MSCs for craniofacial bone homeostasis and repair. PMID:25799059

Pancreatic exocrine adult cells and placental stem cells co-culture. Working together is always the best way to go.

PubMed

Suşman, S; Rus-Ciucă, D; Soriţău, Olga; Tomuleasa, C; Buigă, R; Mihu, D; Pop, V I; Mihu, Carmen Mihaela

2011-01-01

The progress made in the last few years have managed to come up withy the possibility of using different stem cell types in an endeavor to correct the alterations that appear in different degenerative diseases. The pancreas, an organ with extremely low regenerative capacity, both for the endocrine and for the exocrine component, is an organ perfect for cell therapy in the hope of restoring its function and cure diabetes mellitus or chronic pancreatitis. One main issue in the stem cell transplantation problem is represented by the influence of the cellular niche, formed by completely differentiated cells, on the phenotype and function of the transplanted cells. In this study, we challenge current knowledge in the field by evaluating the influence of exocrine pancreatic cells on placental stem-like cells using the co-culture technique. In our experiments, we used two different protocols in which adult pancreatic cells were cultured together with mesenchymal stem cells isolated from human placenta. In the case of the first protocol, we seeded pancreatic cells on a pre-adhered single-cell layer of mesenchymal stem cells and in the second one, the seeding of two cell populations in suspension was done at the same time, after passage. During the experiment, we evaluated the alteration of the morphology of the placental cells using and inverted phase microscope and reverse transcriptase-PCR. Based on morphology, in both cases the interaction between epithelial pancreatic cells and placental ones have determined a change in phenotype from mesenchymal to epithelial-like. Taking into consideration the gene expression, placental stem cells have maintained pluripotency gene expression throughout the study. They also expressed pancreatic amylase. These experiments bring out the plasticity of placental stem cells, the cell microenvironment with a decisive part in phenotype and the level of gene expression. The results obtained in vitro can bring a new picture on the effects of the pancreatic stem cell niche.

Detonation nanodiamond complexes with cancer stem cells inhibitors or paracrine products of mesenchymal stem cells as new potential medications

NASA Astrophysics Data System (ADS)

Konoplyannikov, A. G.; Alekseenskiy, A. E.; Zlotin, S. G.; Smirnov, B. B.; Kalsina, S. Sh.; Lepehina, L. A.; Semenkova, I. V.; Agaeva, E. V.; Baboyan, S. B.; Rjumshina, E. A.; Nosachenko, V. V.; Konoplyannikov, M. A.

2015-09-01

Combined use of complexes of the most active chemotherapeutic drugs and detonation nanodiamonds (DND) is a new trend in cancer therapy, which is probably related to selective chemotherapeutic drug delivery by DND to the zone of so-called cancer stem cells (CSC). Stable DND complexes of 4-5 nm size with salinomycin—a strong CSC inhibitor—have been obtained (as a suspension). It has been demonstrated that a complex administration considerably increases the drug antitumor effect on the transplantable tumor of LLC mice. A similar effect has been observed in CSC models in vivo, obtained by exposure of stem cells of normal mice tissues to a carcinogen 1,2-dimethylhydrazine. It has also been found out, that administration of DND complexes with the conditioned medium from mesenchymal stem cells (MSC) cultures to mice results in a considerable stimulation of stem cell pools in normal mice tissues, which can be used in regenerative medicine.

Stem cells and aging from a quasi-immortal point of view.

PubMed

Boehm, Anna-Marei; Rosenstiel, Philip; Bosch, Thomas C G

2013-11-01

Understanding aging and how it affects an organism's lifespan is a fundamental problem in biology. A hallmark of aging is stem cell senescence, the decline of functionality, and number of somatic stem cells, resulting in an impaired regenerative capacity and reduced tissue function. In addition, aging is characterized by profound remodeling of the immune system and a quantitative decline of adequate immune responses, a phenomenon referred to as immune-senescence. Yet, what is causing stem cell and immune-senescence? This review discusses experimental studies of potentially immortal Hydra which have made contributions to answering this question. Hydra transcription factor FoxO has been shown to modulate both stem cell proliferation and innate immunity, lending strong support to a role of FoxO as critical rate-of-aging regulator from Hydra to human. Constructing a model of how FoxO responds to diverse environmental factors provides a framework for how stem cell factors might contribute to aging. © 2013 WILEY Periodicals, Inc.

The effect of Bcr-Abl protein tyrosine kinase on maturation and proliferation of primitive haematopoietic cells.

PubMed Central

Buckle, A. M.; Mottram, R.; Pierce, A.; Lucas, G. S.; Russell, N.; Miyan, J. A.; Whetton, A. D.

2000-01-01

BACKGROUND: Chronic Myeloid Leukaemia (CML) is characterised by the chromosomal translocation resulting in expression of the Bcr-Abl protein tyrosine kinase (PTK) in early stem cells and their progeny. However the precise nature of Bcr-Abl effects in primitive CML stem cells remains a matter of active debate. MATERIALS AND METHODS: Extremely primitive Bcr-Abl fusion positive cells were purified from patients with CML using multiparameter flow cytometric analysis of CD34, Thy, and lineage marker (Lin) expression, plus rhodamine-123 (Rh-123) brightness. Progenitor cells of increasing maturity were examined for cycling status by flow cytometry and their proliferative status directly correlated with cell phenotype. The activation status of a key transcription factor, signal transducers and activators of transcription (STAT-5), was also analyzed by immunocytochemistry. RESULTS: The most primitive stem cells currently defined (CD34+Lin-Thy+ Rh-1231o) were present as a lower proportion of the stem cell compartment (CD34+Lin-) of CML patients at presentation than of normal individuals (2.3% +/- 0.4 compared with 5.1% +/- 0.6 respectively). Conversely there was a significantly higher proportion of the more mature cells (CD34+Lin-Thy-Rh-123 hi) in CML patients than in normal individuals (79.3 +/- 1.8 compared with 70.9 +/- 3.3). No primitive subpopulation of CML CD34+Lin- cells was cycling to a significantly greater degree than cells from normal donors, in fact, late progenitor cells (CD34+Lin+) were cycling significantly less in CML samples than normal samples. STAT5, however, was observed to be activated in CML cells. CONCLUSIONS: We conclude that no subpopulation of CML stem cells displays significantly increased cell cycling. Thus, increased cycling cannot be a direct consequence of Bcr-Abl PTK acquisition in highly enriched stem cells from patients with CML. In vivo CML need not be considered a disease of unbridled stem cell proliferation, but a subtle defect in the balance between self renewal and maturation. PMID:11126203

Characterization and Classification of Mesenchymal Stem Cells in Several Species Using Surface Markers for Cell Therapy Purposes.

PubMed

Ghaneialvar, Hori; Soltani, Leila; Rahmani, Hamid Reza; Lotfi, Abbas Sahebghadam; Soleimani, Masoud

2018-01-01

Mesenchymal stem cells are multipotent cells capable of replicating as undifferentiated cells, and have the potential of differentiating into mesenchymal tissue lineages such as osteocytes, adipocytes and chondrocytes. Such lineages can then be used in cell therapy. The aim of present study was to characterize bone marrow derived mesenchymal stem cells in four different species, including: sheep, goat, human and mouse. Human bone-marrow mesenchymal stem cells were purchased, those of sheep and goat were isolated from fetal bone marrow, and those of mouse were collected by washing bone cavity of femur and tibia with DMEM/F12. Using flow-cytometry, they were characterized by CD surface antigens. Furthermore, cells of third passage were examined for their osteogenic and adipogenic differentiation potential by oil red and alizarin red staining respectively. According to the results, CD markers studied in the four groups of mesenchymal stem cells showed a different expression. Goat and sheep expressed CD44 and CD166, and weakly expressed CD34, CD45, CD105 and CD90. Similarly, human and mouse mesenchymal cells expressed CD44, CD166, CD105 and CD90 whereas the expression of CD34 and CD45 was negative. In conclusion, although all mesenchymal stem cells display plastic adherence and tri-lineage differentiation, not all express the same panel of surface antigens described for human mesenchymal stem cells. Additional panel of CD markers are necessary to characterize regenerative potential and possible application of these stem cells in regenerative medicine and implantology.

The potential of chondrogenic pre-differentiation of adipose-derived mesenchymal stem cells for regeneration in harsh nucleus pulposus microenvironment.

PubMed

Wang, Jingkai; Tao, Yiqing; Zhou, Xiaopeng; Li, Hao; Liang, Chengzhen; Li, Fangcai; Chen, Qi-Xin

2016-12-01

Recent studies indicated that cell-based therapy could be a promising approach to treat intervertebral disc degeneration. Though the harsh microenvironment in disc is still challenging to implanted cells, it could be overcome by pre-conditioning graft cells before transplantation, suggested by previous literatures. Therefore, we designed this study to identify the potential effect of chondrogenic pre-differentiation on adipose-derived mesenchymal stem cells in intervertebral disc-like microenvironment, characterized by limited nutrition, acidic, and high osmosis in vitro. Adipose-derived mesenchymal stem cells of rat were divided into five groups, embedded in type II collagen scaffold, and cultured in chondrogenic differentiation medium for 0, 3, 7, 10, and 14 days. Then, the adipose-derived mesenchymal stem cells were implanted and cultured in intervertebral disc-like condition. The proliferation and differentiation of adipose-derived mesenchymal stem cells were evaluated by cell counting kit-8 test, real-time quantitative polymerase chain reaction, and Western blotting and immunofluorescence analysis. Analyzed by the first week in intervertebral disc-like condition, the results showed relatively greater proliferative capability and extracellular matrix synthesis ability of the adipose-derived mesenchymal stem cells pre-differentiated for 7 and 10 days than the control. We concluded that pre-differentiation of rat adipose-derived mesenchymal stem cells in chondrogenic culture medium for 7 to 10 days could promote the regeneration effect of adipose-derived mesenchymal stem cells in intervertebral disc-like condition, and the pre-differentiated cells could be a promising cell source for disc regeneration medicine.

Embryonic stem cells and prospects for their use in regenerative medicine approaches to motor neurone disease.

PubMed

Christou, Y A; Moore, H D; Shaw, P J; Monk, P N

2007-10-01

Human embryonic stem cells are pluripotent cells with the potential to differentiate into any cell type in the presence of appropriate stimulatory factors and environmental cues. Their broad developmental potential has led to valuable insights into the principles of developmental and cell biology and to the proposed use of human embryonic stem cells or their differentiated progeny in regenerative medicine. This review focuses on the prospects for the use of embryonic stem cells in cell-based therapy for motor neurone disease or amyotrophic lateral sclerosis, a progressive neurodegenerative disease that specifically affects upper and lower motor neurones and leads ultimately to death from respiratory failure. Stem cell-derived motor neurones could conceivably be used to replace the degenerated cells, to provide authentic substrates for drug development and screening and for furthering our understanding of disease mechanisms. However, to reliably and accurately culture motor neurones, the complex pathways by which differentiation occurs in vivo must be understood and reiterated in vitro by embryonic stem cells. Here we discuss the need for new therapeutic strategies in the treatment of motor neurone disease, the developmental processes that result in motor neurone formation in vivo, a number of experimental approaches to motor neurone production in vitro and recent progress in the application of stem cells to the treatment and understanding of motor neurone disease.

Loss of DNA mismatch repair imparts a selective advantage in planarian adult stem cells.

PubMed

Hollenbach, Jessica P; Resch, Alissa M; Palakodeti, Dasaradhi; Graveley, Brenton R; Heinen, Christopher D

2011-01-01

Lynch syndrome (LS) leads to an increased risk of early-onset colorectal and other types of cancer and is caused by germline mutations in DNA mismatch repair (MMR) genes. Loss of MMR function results in a mutator phenotype that likely underlies its role in tumorigenesis. However, loss of MMR also results in the elimination of a DNA damage-induced checkpoint/apoptosis activation barrier that may allow damaged cells to grow unchecked. A fundamental question is whether loss of MMR provides pre-cancerous stem cells an immediate selective advantage in addition to establishing a mutator phenotype. To test this hypothesis in an in vivo system, we utilized the planarian Schmidtea mediterranea which contains a significant population of identifiable adult stem cells. We identified a planarian homolog of human MSH2, a MMR gene which is mutated in 38% of LS cases. The planarian Smed-msh2 is expressed in stem cells and some progeny. We depleted Smed-msh2 mRNA levels by RNA-interference and found a striking survival advantage in these animals treated with a cytotoxic DNA alkylating agent compared to control animals. We demonstrated that this tolerance to DNA damage is due to the survival of mitotically active, MMR-deficient stem cells. Our results suggest that loss of MMR provides an in vivo survival advantage to the stem cell population in the presence of DNA damage that may have implications for tumorigenesis.

Loss of DNA Mismatch Repair Imparts a Selective Advantage in Planarian Adult Stem Cells

PubMed Central

Hollenbach, Jessica P.; Resch, Alissa M.; Palakodeti, Dasaradhi; Graveley, Brenton R.; Heinen, Christopher D.

2011-01-01

Lynch syndrome (LS) leads to an increased risk of early-onset colorectal and other types of cancer and is caused by germline mutations in DNA mismatch repair (MMR) genes. Loss of MMR function results in a mutator phenotype that likely underlies its role in tumorigenesis. However, loss of MMR also results in the elimination of a DNA damage-induced checkpoint/apoptosis activation barrier that may allow damaged cells to grow unchecked. A fundamental question is whether loss of MMR provides pre-cancerous stem cells an immediate selective advantage in addition to establishing a mutator phenotype. To test this hypothesis in an in vivo system, we utilized the planarian Schmidtea mediterranea which contains a significant population of identifiable adult stem cells. We identified a planarian homolog of human MSH2, a MMR gene which is mutated in 38% of LS cases. The planarian Smed-msh2 is expressed in stem cells and some progeny. We depleted Smed-msh2 mRNA levels by RNA-interference and found a striking survival advantage in these animals treated with a cytotoxic DNA alkylating agent compared to control animals. We demonstrated that this tolerance to DNA damage is due to the survival of mitotically active, MMR-deficient stem cells. Our results suggest that loss of MMR provides an in vivo survival advantage to the stem cell population in the presence of DNA damage that may have implications for tumorigenesis. PMID:21747960

Learn About Stem Cells

MedlinePlus

... Handbook Stem Cell Glossary Search Toggle Nav Stem Cell Basics Stem cells are the foundation from which ... Home > Learn About Stem Cells > Stem Cell Basics Cells in the human body The human body comprises ...

In vitro long-term development of cultured inner ear stem cells of newborn rat.

PubMed

Carricondo, Francisco; Iglesias, Mari Cruz; Rodríguez, Fernando; Poch-Broto, Joaquin; Gil-Loyzaga, Pablo

2010-10-01

The adult mammalian auditory receptor lacks any ability to repair and/or regenerate after injury. However, the late developing cochlea still contains some stem-cell-like elements that might be used to regenerate damaged neurons and/or cells of the organ of Corti. Before their use in any application, stem cell numbers need to be amplified because they are usually rare in late developing and adult tissues. The numerous re-explant cultures required for the progressive amplification process can result in a spontaneous differentiation process. This aspect has been implicated in the tumorigenicity of stem cells when transplanted into a tissue. The aim of this study has been to determine whether cochlear stem cells can proliferate and differentiate spontaneously in long-term cultures without the addition of any factor that might influence these processes. Cochlear stem cells, which express nestin protein, were cultured in monolayers and fed with DMEM containing 5% FBS. They quickly organized themselves into typical spheres exhibiting a high proliferation rate, self-renewal property, and differentiation ability. Secondary cultures of these stem cell spheres spontaneously differentiated into neuroectodermal-like cells. The expression of nestin, glial-fibrillary-acidic protein, vimentin, and neurofilaments was evaluated to identify early differentiation. Nestin expression appeared in primary and secondary cultures. Other markers were also identified in differentiating cells. Further research might demonstrate the spontaneous differentiation of cochlear stem cells and their teratogenic probability when they are used for transplantation.

Efficient generation of transgene- and feeder-free induced pluripotent stem cells from human dental mesenchymal stem cells and their chemically defined differentiation into cardiomyocytes.

PubMed

Tan, Xiaobing; Dai, Qingli; Guo, Tao; Xu, Jingshu; Dai, Qingyuan

2018-01-22

Advance in stem cell research resulted in several processes to generate induced pluripotent stem cells (iPSCs) from adult somatic cells. In our previous study, the reprogramming of iPSCs from human dental mesenchymal stem cells (MSCs) including SCAP and DPSCs, has been reported. Herein, safe iPSCs were reprogrammed from SCAP and DPSCs using non-integrating RNA virus vector, which is an RNA virus carrying no risk of altering host genome. DPSCs- and SCAP-derived iPSCs exhibited the characteristics of the classical morphology with human embryonic stem cells (hESCs) without integration of foreign genes, indicating the potential of their clinical application. Moreover, induced PSCs showed the capacity of self-renewal and differentiation into cardiac myocytes. We have achieved the differentiation of hiPSCs to cardiomyocytes lineage under serum and feeder-free conditions, using a chemically defined medium CDM3. In CDM3, hiPSCs differentiation is highly generating cardiomyocytes. The results showed this protocol produced contractile sheets of up to 97.2% TNNT2 cardiomyocytes after purification. Furthermore, derived hiPSCs differentiated to mature cells of the three embryonic germ layers in vivo and in vitro of beating cardiomyocytes. The above whole protocol enables the generation of large scale of highly pure cardiomyocytes as needed for cellular therapy. Copyright © 2017. Published by Elsevier Inc.

Tumor-stem cells interactions by fluorescence imaging

NASA Astrophysics Data System (ADS)

Meleshina, Aleksandra V.; Cherkasova, Elena I.; Sergeeva, Ekaterina; Turchin, Ilya V.; Kiseleva, Ekaterina V.; Dashinimaev, Erdem B.; Shirmanova, Marina V.; Zagaynova, Elena V.

2013-02-01

Recently, great deal of interest is investigation the function of the stem cells (SC) in tumors. In this study, we studied «recipient-tumor- fluorescent stem cells » system using the methods of in vivo imaging and laser scanning microscopy (LSM). We used adipose-derived adult stem (ADAS) cells of human lentiviral transfected with the gene of fluorescent protein Turbo FP635. ADAS cells were administrated into nude mice with transplanted tumor HeLa Kyoto (human cervical carcinoma) at different stages of tumor growth (0-8 days) intravenously or into tumor. In vivo imaging was performed on the experimental setup for epi - luminescence bioimaging (IAP RAS, Nizhny Novgorod). The results of the imaging showed localization of fluorophore tagged stem cells in the spleen on day 5-9 after injection. The sensitivity of the technique may be improved by spectral separation autofluorescence and fluorescence of stem cells. We compared the results of in vivo imaging and confocal laser scanning microscopy (LSM 510 META, Carl Zeiss, Germany). Internal organs of the animals and tumor tissue were investigated. It was shown that with i.v. injection of ADAS, bright fluorescent structures with spectral characteristics corresponding to TurboFP635 protein are locally accumulated in the marrow, lungs and tumors of animals. These findings indicate that ADAS cells integrate in the animal body with transplanted tumor and can be identified by fluorescence bioimaging techniques in vivo and ex vivo.

Erythroid differentiation of human induced pluripotent stem cells is independent of donor cell type of origin.

PubMed

Dorn, Isabel; Klich, Katharina; Arauzo-Bravo, Marcos J; Radstaak, Martina; Santourlidis, Simeon; Ghanjati, Foued; Radke, Teja F; Psathaki, Olympia E; Hargus, Gunnar; Kramer, Jan; Einhaus, Martin; Kim, Jeong Beom; Kögler, Gesine; Wernet, Peter; Schöler, Hans R; Schlenke, Peter; Zaehres, Holm

2015-01-01

Epigenetic memory in induced pluripotent stem cells, which is related to the somatic cell type of origin of the stem cells, might lead to variations in the differentiation capacities of the pluripotent stem cells. In this context, induced pluripotent stem cells from human CD34(+) hematopoietic stem cells might be more suitable for hematopoietic differentiation than the commonly used fibroblast-derived induced pluripotent stem cells. To investigate the influence of an epigenetic memory on the ex vivo expansion of induced pluripotent stem cells into erythroid cells, we compared induced pluripotent stem cells from human neural stem cells and human cord blood-derived CD34(+) hematopoietic stem cells and evaluated their potential for differentiation into hematopoietic progenitor and mature red blood cells. Although genome-wide DNA methylation profiling at all promoter regions demonstrates that the epigenetic memory of induced pluripotent stem cells is influenced by the somatic cell type of origin of the stem cells, we found a similar hematopoietic induction potential and erythroid differentiation pattern of induced pluripotent stem cells of different somatic cell origin. All human induced pluripotent stem cell lines showed terminal maturation into normoblasts and enucleated reticulocytes, producing predominantly fetal hemoglobin. Differences were only observed in the growth rate of erythroid cells, which was slightly higher in the induced pluripotent stem cells derived from CD34(+) hematopoietic stem cells. More detailed methylation analysis of the hematopoietic and erythroid promoters identified similar CpG methylation levels in the induced pluripotent stem cell lines derived from CD34(+) cells and those derived from neural stem cells, which confirms their comparable erythroid differentiation potential. Copyright© Ferrata Storti Foundation.

Indispensable role of Notch ligand-dependent signaling in the proliferation and stem cell niche maintenance of APC-deficient intestinal tumors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nakata, Toru; Shimizu, Hiromichi; Department of Medicine, University of California, San Francisco, San Francisco, CA

Ligand-dependent activation of Notch signaling is required to maintain the stem-cell niche of normal intestinal epithelium. However, the precise role of Notch signaling in the maintenance of the intestinal tumor stem cell niche and the importance of the RBPJ-independent non-canonical pathway in intestinal tumors remains unknown. Here we show that Notch signaling was activated in LGR5{sup +ve} cells of APC-deficient mice intestinal tumors. Accordingly, Notch ligands, including Jag1, Dll1, and Dll4, were expressed in these tumors. In vitro studies using tumor-derived organoids confirmed the intrinsic Notch activity-dependent growth of tumor cells. Surprisingly, the targeted deletion of Jag1 but not RBPJ inmore » LGR5{sup +ve} tumor-initiating cells resulted in the silencing of Hes1 expression, disruption of the tumor stem cell niche, and dramatic reduction in the proliferation activity of APC-deficient intestinal tumors in vivo. Thus, our results highlight the importance of ligand-dependent non-canonical Notch signaling in the proliferation and maintenance of the tumor stem cell niche in APC-deficient intestinal adenomas. - Highlights: • Notch signaling is activated in LGR5{sup +ve} cells of APC-deficient intestinal tumors. • Lack of Jag1 but not RBPJ disrupts stem cell niche formation in those tumors. • Lack of Jag1 reduces the proliferation activity of APC-deficient intestinal tumors.« less

Isolation and Expansion of Hepatic Stem-like Cells from a Healthy Rat Liver and their Efficient Hepatic Differentiation of under Well-defined Vivo Hepatic like Microenvironment in a Multiwell Bioreactor

PubMed Central

Giri, Shibashish; Acikgöz, Ali; Bader, Augustinus

2015-01-01

Background Currently, undifferentiated cells are found in all tissue and term as local stem cells which are quiescent in nature and less in number under normal healthy conditions but activate upon injury and repair the tissue or organs via automated activating mechanism. Due to very scanty presence of local resident somatic local stem cells in healthy organs, isolation and expansion of these adult stems is an immense challenge for medical research and cell based therapy. Particularly organ like liver, there is an ongoing controversy about existence of liver stem cells. Methods Herein, Hepatic stem cells population was identified during culture of primary hepatocyte cells upon immediate isolation of primary hepatocyte cells. These liver stem cells has been expanded extensively and differentiated into primary hepatocytes under defined culture conditions in a nanostructured self assembling peptides modular bioreactor that mimic the state of art of liver microenvironment and compared with Matrigel as a positive control. Nanostructured self assembling peptides were used a defined extracellular matrix and Matrigel was used for undefined extracellular matrix. Proliferation of hepatic stem cells was investigated by two strategies. First strategy is to provide high concentration of hepatocyte growth factor (HGF) and second strategy is to evaluate the role of recombinant human erythropoietin (rHuEPO) in presence of trauma/ischemia cytokines (IL-6, TNF-α). Expansion to hepatic differentiation is observed by morphological analysis and was evaluated for the expression of hepatocyte-specific genes using RT-PCR and biochemical methods. Results Hepatocyte-specific genes are well expressed at final stage (day 21) of differentiation period. The differentiated hepatocytes exhibited functional hepatic characteristics such as albumin secretion, urea secretion and cytochrome P450 expression. Additionally, immunofluorescence analysis revealed that hepatic stem cells derived hepatocytes exhibited mature hepatocyte markers (albumin, CK-19, CPY3A1, alpha 1-antitrypsin). Expansion and hepatic differentiation was efficiently in nanostructured self assembling peptides without such batch to batch variation while there was much variation in Matrigel coated bioreactor. In conclusion, the results of the study suggest that the nanostructured self assembling peptides coated bioreactor supports expansion as well as hepatic differentiation of liver stem cells which is superior than Matrigel. Conclusion This defined microenvironment conditions in bioreactor module can be useful for research involving bioartificial liver system, stem cell research and engineered liver tissue which could contribute to regenerative cell therapies or drug discovery and development. PMID:26155038

[Progress in stem cells and regenerative medicine].

PubMed

Wang, Libin; Zhu, He; Hao, Jie; Zhou, Qi

2015-06-01

Stem cells have the ability to differentiate into all types of cells in the body and therefore have great application potential in regenerative medicine, in vitro disease modelling and drug screening. In recent years, stem cell technology has made great progress, and induced pluripotent stem cell technology revolutionizes the whole stem cell field. At the same time, stem cell research in our country has also achieved great progress and becomes an indispensable power in the worldwide stem cell research field. This review mainly focuses on the research progress in stem cells and regenerative medicine in our country since the advent of induced pluripotent stem cell technology, including induced pluripotent stem cells, transdifferentiation, haploid stem cells, and new gene editing tools.

Application of Graphene Based Nanotechnology in Stem Cells Research.

PubMed

Hu, Shanshan; Zeng, Yongxiang; Yang, Shuying; Qin, Han; Cai, He; Wang, Jian

2015-09-01

The past several years have witnessed significant advances in stem cell therapy, tissue engineering and regenerative medicine. Graphene, with its unique properties such as high electrical conductivity, elasticity and good molecule absorption, have potential for creating the next generation of biomaterials. This review summarizes the interrelationship between graphene and stem cells. The analysis of graphene when applied on mesenchymal stem cells, neural stem cells, induced pluripotent stem cells, embryonic stem cells, periodontal ligament stem cells, human adipose-derived stem cells and cancer stem cells, and how graphene influences cell behavior and differentiation are discussed in details.

Epigenetic modulation of the miR-200 family is associated with transition to a breast cancer stem-cell-like state.

PubMed

Lim, Yat-Yuen; Wright, Josephine A; Attema, Joanne L; Gregory, Philip A; Bert, Andrew G; Smith, Eric; Thomas, Daniel; Lopez, Angel F; Drew, Paul A; Khew-Goodall, Yeesim; Goodall, Gregory J

2013-05-15

The miR-200 family is a key regulator of the epithelial-mesenchymal transition, however, its role in controlling the transition between cancer stem-cell-like and non-stem-cell-like phenotypes is not well understood. We utilized immortalized human mammary epithelial (HMLE) cells to investigate the regulation of the miR-200 family during their conversion to a stem-like phenotype. HMLE cells were found to be capable of spontaneous conversion from a non-stem to a stem-like phenotype and this conversion was accompanied by the loss of miR-200 expression. Stem-like cell fractions isolated from metastatic breast cancers also displayed loss of miR-200 indicating similar molecular changes may occur during breast cancer progression. The phenotypic change observed in HMLE cells was directly controlled by miR-200 because restoration of its expression decreased stem-like properties while promoting a transition to an epithelial phenotype. Investigation of the mechanisms controlling miR-200 expression revealed both DNA methylation and histone modifications were significantly altered in the stem-like and non-stem phenotypes. In particular, in the stem-like phenotype, the miR-200b-200a-429 cluster was silenced primarily through polycomb group-mediated histone modifications whereas the miR-200c-141 cluster was repressed by DNA methylation. These results indicate that the miR-200 family plays a crucial role in the transition between stem-like and non-stem phenotypes and that distinct epigenetic-based mechanisms regulate each miR-200 gene in this process. Therapy targeted against miR-200 family members and epigenetic modifications might therefore be applicable to breast cancer.

Biosimilar G-CSF Based Mobilization of Peripheral Blood Hematopoietic Stem Cells for Autologous and Allogeneic Stem Cell Transplantation

PubMed Central

Schmitt, Michael; Publicover, Amy; Orchard, Kim H; Görlach, Matthias; Wang, Lei; Schmitt, Anita; Mani, Jiju; Tsirigotis, Panagiotis; Kuriakose, Reeba; Nagler, Arnon

2014-01-01

The use of granulocyte colony stimulating factor (G-CSF) biosimilars for peripheral blood hematopoietic stem cell (PBSC) mobilization has stimulated an ongoing debate regarding their efficacy and safety. However, the use of biosimilar G-CSF was approved by the European Medicines Agency (EMA) for all the registered indications of the originator G-CSF (Neupogen®) including mobilization of stem cells. Here, we performed a comprehensive review of published reports on the use of biosimilar G-CSF covering patients with hematological malignancies as well as healthy donors that underwent stem cell mobilization at multiple centers using site-specific non-randomized regimens with a biosimilar G-CSF in the autologous and allogeneic setting. A total of 904 patients mostly with hematological malignancies as well as healthy donors underwent successful autologous or allogeneic stem cell mobilization, respectively, using a biosimilar G-CSF (520 with Ratiograstim®/Tevagrastim, 384 with Zarzio®). The indication for stem cell mobilization in hematology patients included 326 patients with multiple myeloma, 273 with Non-Hodgkin's lymphoma (NHL), 79 with Hodgkin's lymphoma (HL), and other disease. 156 sibling or volunteer unrelated donors were mobilized using biosimilar G-CSF. Mobilization resulted in good mobilization of CD34+ stem cells with side effects similar to originator G-CSF. Post transplantation engraftment did not significantly differ from results previously documented with the originator G-CSF. The side effects experienced by the patients or donors mobilized by biosimilar G-CSF were minimal and were comparable to those of originator G-CSF. In summary, the efficacy of biosimilar G-CSFs in terms of PBSC yield as well as their toxicity profile are equivalent to historical data with the reference G-CSF. PMID:24505236

Biosimilar G-CSF based mobilization of peripheral blood hematopoietic stem cells for autologous and allogeneic stem cell transplantation.

PubMed

Schmitt, Michael; Publicover, Amy; Orchard, Kim H; Görlach, Matthias; Wang, Lei; Schmitt, Anita; Mani, Jiju; Tsirigotis, Panagiotis; Kuriakose, Reeba; Nagler, Arnon

2014-01-01

The use of granulocyte colony stimulating factor (G-CSF) biosimilars for peripheral blood hematopoietic stem cell (PBSC) mobilization has stimulated an ongoing debate regarding their efficacy and safety. However, the use of biosimilar G-CSF was approved by the European Medicines Agency (EMA) for all the registered indications of the originator G-CSF (Neupogen (®) ) including mobilization of stem cells. Here, we performed a comprehensive review of published reports on the use of biosimilar G-CSF covering patients with hematological malignancies as well as healthy donors that underwent stem cell mobilization at multiple centers using site-specific non-randomized regimens with a biosimilar G-CSF in the autologous and allogeneic setting. A total of 904 patients mostly with hematological malignancies as well as healthy donors underwent successful autologous or allogeneic stem cell mobilization, respectively, using a biosimilar G-CSF (520 with Ratiograstim®/Tevagrastim, 384 with Zarzio®). The indication for stem cell mobilization in hematology patients included 326 patients with multiple myeloma, 273 with Non-Hodgkin's lymphoma (NHL), 79 with Hodgkin's lymphoma (HL), and other disease. 156 sibling or volunteer unrelated donors were mobilized using biosimilar G-CSF. Mobilization resulted in good mobilization of CD34+ stem cells with side effects similar to originator G-CSF. Post transplantation engraftment did not significantly differ from results previously documented with the originator G-CSF. The side effects experienced by the patients or donors mobilized by biosimilar G-CSF were minimal and were comparable to those of originator G-CSF. In summary, the efficacy of biosimilar G-CSFs in terms of PBSC yield as well as their toxicity profile are equivalent to historical data with the reference G-CSF.

A stem cell apostasy: A tale of 4 H words

PubMed Central

Quesenberry, Peter J.; Goldberg, Laura R.; Dooner, Mark S.

2014-01-01

The field of hematopoietic stem cell biology has become increasingly dominated by the pursuit and study of highly purified populations of hematopoietic stem cells (HSCs). Such HSCs are typically isolated based on their cell surface marker expression patterns and ultimately defined by their multipotency and capacity for self-generation. However, even with progressively more stringent stem cell separation techniques, the resultant HSC population remains heterogeneous with respect to both self-renewal and differentiation capacity. Critical studies on un-separated whole bone marrow (WBM) have definitively shown that long-term engraftable hematopoietic stem cells are in active cell cycle and thus continually changing phenotype. Therefore, they cannot be purified by current approaches dependent on stable surface epitope expression because the surface markers are continually changing as well. These critical cycling cells are discarded with current stem cell purifications. Despite this, research defining such characteristics as self-renewal capacity, lineage-commitment, bone marrow niches, and proliferative state of HSCs continues to focus predominantly on this small sub-population of purified marrow cells. This review discusses the research leading to the hierarchical model of hematopoiesis and questions the dogmas pertaining to HSC quiescence and purification. PMID:25183450

Improved Survival After Transplantation of More Donor Plasmacytoid Dendritic or Naïve T Cells From Unrelated-Donor Marrow Grafts: Results From BMTCTN 0201

PubMed Central

Waller, Edmund K.; Logan, Brent R.; Harris, Wayne A.C.; Devine, Steven M.; Porter, David L.; Mineishi, Shin; McCarty, John M.; Gonzalez, Corina E.; Spitzer, Thomas R.; Krijanovski, Oleg I.; Linenberger, Michael L.; Woolfrey, Ann; Howard, Alan; Wu, Juan; Confer, Dennis L.; Anasetti, Claudio

2014-01-01

Purpose To characterize relationships between specific immune cell subsets in bone marrow (BM) or granulocyte colony-stimulating factor–mobilized peripheral blood (PB) stem cells collected from unrelated donors and clinical outcomes of patients undergoing transplantation in BMTCTN 0201. Patients and Methods Fresh aliquots of 161 BM and 147 PB stem-cell allografts from North American donors randomly assigned to donate BM or PB stem cells and numbers of transplanted cells were correlated with overall survival (OS), relapse, and graft-versus-host disease (GvHD). Results Patients with evaluable grafts were similar to all BMTCTN 0201 patients. The numbers of plasmacytoid dendritic cells (pDCs) and naïve T cells (Tns) in BM allografts were independently associated with OS in multivariable analyses including recipient and donor characteristics, such as human leukocyte antigen mismatch, age, and use of antithymocyte globulin. BM recipients of > median number of pDCs, naïve CD8+ T cells (CD8Tns), or naïve CD4+ T cells (CD4Tns) had better 3-year OS (pDCs, 56% v 35%; P = .025; CD8Tns, 56% v 37%; P = .012; CD4Tns, 55% v 37%; P = .009). Transplantation of more BM Tns was associated with less grade 3 to 4 acute GvHD but similar rates of relapse. Transplantation of more BM pDCs was associated with fewer deaths resulting from GvHD or from graft rejection. Analysis of PB grafts did not identify a donor cell subset significantly associated with OS, relapse, or GvHD. Conclusion Donor immune cells in BM but not PB stem-cell grafts were associated with survival after unrelated-donor allogeneic hematopoietic stem-cell transplantation. The biologic activity of donor immune cells in allogeneic transplantation varied between graft sources. Donor grafts with more BM-derived Tns and pDCs favorably regulated post-transplantation immunity in allogeneic hematopoietic stem-cell transplantation. PMID:24982459

Lipogems Product Treatment Increases the Proliferation Rate of Human Tendon Stem Cells without Affecting Their Stemness and Differentiation Capability

PubMed Central

Randelli, Pietro; Menon, Alessandra; Ragone, Vincenza; Creo, Pasquale; Bergante, Sonia; Randelli, Filippo; De Girolamo, Laura; Alfieri Montrasio, Umberto; Banfi, Giuseppe; Cabitza, Paolo; Tettamanti, Guido; Anastasia, Luigi

2016-01-01

Increasing the success rate of rotator cuff healing remains tremendous challenge. Among many approaches, the possibility of activating resident stem cells in situ, without the need to isolate them from biopsies, could represent valuable therapeutic strategy. Along this line, it has been recently demonstrated that lipoaspirate product, Lipogems, contains and produces growth-factors that may activate resident stem cells. In this study, human tendon stem cells (hTSCs) from the rotator cuff were cocultured in a transwell system with the Lipogems lipoaspirate product and compared to control untreated cells in terms of cell proliferation, morphology, stem cell marker and VEGF expression, and differentiation and migration capabilities. Results showed that the Lipogems product significantly increases the proliferation rate of hTSCs without altering their stemness and differentiation capability. Moreover, treated cells increase the expression of VEGF, which is crucial for the neovascularization of the tissue during the healing process. Overall, this study supports that directly activating hTSCs with the Lipogems lipoaspirate could represent a new practical therapeutic approach. In fact, obtaining a lipoaspirate is easier, safer, and more cost-effective than harvesting cells from tendon or bone marrow biopsies, expanding them in GMP facility and then reinjecting them in the patient. PMID:27057170

Lipogems Product Treatment Increases the Proliferation Rate of Human Tendon Stem Cells without Affecting Their Stemness and Differentiation Capability.

PubMed

Randelli, Pietro; Menon, Alessandra; Ragone, Vincenza; Creo, Pasquale; Bergante, Sonia; Randelli, Filippo; De Girolamo, Laura; Alfieri Montrasio, Umberto; Banfi, Giuseppe; Cabitza, Paolo; Tettamanti, Guido; Anastasia, Luigi

2016-01-01

Increasing the success rate of rotator cuff healing remains tremendous challenge. Among many approaches, the possibility of activating resident stem cells in situ, without the need to isolate them from biopsies, could represent valuable therapeutic strategy. Along this line, it has been recently demonstrated that lipoaspirate product, Lipogems, contains and produces growth-factors that may activate resident stem cells. In this study, human tendon stem cells (hTSCs) from the rotator cuff were cocultured in a transwell system with the Lipogems lipoaspirate product and compared to control untreated cells in terms of cell proliferation, morphology, stem cell marker and VEGF expression, and differentiation and migration capabilities. Results showed that the Lipogems product significantly increases the proliferation rate of hTSCs without altering their stemness and differentiation capability. Moreover, treated cells increase the expression of VEGF, which is crucial for the neovascularization of the tissue during the healing process. Overall, this study supports that directly activating hTSCs with the Lipogems lipoaspirate could represent a new practical therapeutic approach. In fact, obtaining a lipoaspirate is easier, safer, and more cost-effective than harvesting cells from tendon or bone marrow biopsies, expanding them in GMP facility and then reinjecting them in the patient.

Prion potency in stem cells biology.

PubMed

Lopes, Marilene H; Santos, Tiago G

2012-01-01

Prion protein (PrP) can be considered a pivotal molecule because it interacts with several partners to perform a diverse range of critical biological functions that might differ in embryonic and adult cells. In recent years, there have been major advances in elucidating the putative role of PrP in the basic biology of stem cells in many different systems. Here, we review the evidence indicating that PrP is a key molecule involved in driving different aspects of the potency of embryonic and tissue-specific stem cells in self-perpetuation and differentiation in many cell types. It has been shown that PrP is involved in stem cell self-renewal, controlling pluripotency gene expression, proliferation, and neural and cardiomyocyte differentiation. PrP also has essential roles in distinct processes that regulate tissue-specific stem cell biology in nervous and hematopoietic systems and during muscle regeneration. Results from our own investigations have shown that PrP is able to modulate self-renewal and proliferation in neural stem cells, processes that are enhanced by PrP interactions with stress inducible protein 1 (STI1). Thus, the available data reveal the influence of PrP in acting upon the maintenance of pluripotent status or the differentiation of stem cells from the early embryogenesis through adulthood.

A revisionist history of adult marrow stem cell biology or 'they forgot about the discard'.

PubMed

Quesenberry, P; Goldberg, L

2017-08-01

The adult marrow hematopoietic stem cell biology has largely been based on studies of highly purified stem cells. This is unfortunate because during the stem cell purification the great bulk of stem cells are discarded. These cells are actively proliferating. The final purified stem cell is dormant and not representative of the whole stem cell compartment. Thus, a large number of studies on the cellular characteristics, regulators and molecular details of stem cells have been carried on out of non-represented cells. Niche studies have largely pursued using these purified stem cells and these are largely un-interpretable. Other considerations include the distinction between baseline and transplant stem cells and the modulation of stem cell phenotype by extracellular vesicles, to cite a non-inclusive list. Work needs to proceed on characterizing the true stem cell population.

The usefulness of three-dimensional cell culture in induction of cancer stem cells from esophageal squamous cell carcinoma cell lines

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fujiwara, Daisuke; Kato, Kazunori, E-mail: kzkatou@juntendo.ac.jp; Department of Atopy Research Center, Juntendo University School of Medicine, 2-1-1 Hongo, Bunkyo-ku, Tokyo 113-8421

2013-05-17

Highlights: •Spheroids were created from esophageal carcinoma cells using NanoCulture® Plates. •The proportion of strongly ALDH-positive cells increased in 3-D culture. •Expression of cancer stem cell-related genes was enhanced in 3-D culture. •CA-9 expression was enhanced, suggesting hypoxia had been induced in 3-D culture. •Drug resistance was increased. 3-D culture is useful for inducing cancer stem cells. -- Abstract: In recent years, research on resistance to chemotherapy and radiotherapy in cancer treatment has come under the spotlight, and researchers have also begun investigating the relationship between resistance and cancer stem cells. Cancer stem cells are assumed to be present inmore » esophageal cancer, but experimental methods for identification and culture of these cells have not yet been established. To solve this problem, we created spheroids using a NanoCulture® Plate (NCP) for 3-dimensional (3-D) cell culture, which was designed as a means for experimentally reproducing the 3-D structures found in the body. We investigated the potential for induction of cancer stem cells from esophageal cancer cells. Using flow cytometry we analyzed the expression of surface antigen markers CD44, CD133, CD338 (ABCG2), CD318 (CDCP1), and CD326 (EpCAM), which are known cancer stem cell markers. None of these surface antigen markers showed enhanced expression in 3-D cultured cells. We then analyzed aldehyde dehydrogenase (ALDH) enzymatic activity using the ALDEFLUOR reagent, which can identify immature cells such as stem cells and precursor cells. 3-D-cultured cells were strongly positive for ALDH enzyme activity. We also analyzed the expression of the stem cell-related genes Sox-2, Nanog, Oct3/4, and Lin28 using RT-PCR. Expression of Sox-2, Nanog, and Lin28 was enhanced. Analysis of expression of the hypoxic surface antigen marker carbonic anhydrase-9 (CA-9), which is an indicator of cancer stem cell induction and maintenance, revealed that CA-9 expression was enhanced, suggesting that hypoxia had been induced. Comparison of cancer drug resistance using cisplatin and doxorubicin in 3-D-cultured esophageal cancer cells showed that cancer drug resistance had increased. These results indicate that 3-D culture of esophageal squamous cell carcinoma lines is a useful method for inducing cancer stem cells.« less

Peripheral blood stem cell mobilization: the CXCR2 ligand GRObeta rapidly mobilizes hematopoietic stem cells with enhanced engraftment properties.

PubMed

Pelus, Louis M; Fukuda, Seiji

2006-08-01

Chemokines direct the movement of leukocytes, including hematopoietic stem and progenitor cells, and can mobilize hematopoietic cells from marrow to peripheral blood where they can be used for transplantation. In this review, we will discuss the stem cell mobilizing activities and mechanisms of action of GRObeta, a CXC chemokine ligand for the CXCR2 receptor. GRObeta rapidly mobilizes short- and long-term repopulating cells in mice and/or monkeys and synergistically enhances mobilization responses when combined with the widely used clinical mobilizer, granulocyte colony-stimulating factor (G-CSF). The hematopoietic graft mobilized by GRObeta contains significantly more CD34(neg), Sca-1+, c-kit+, lineage(neg) (SKL) cells than the graft mobilized by G-CSF. In mice, stem cells mobilized by GRObeta demonstrate a competitive advantage upon long-term repopulation analysis and restore neutrophil and platelet counts significantly faster than cells mobilized by G-CSF. Even greater advantage in repopulation and restoration of hematopoiesis are observed with stem cells mobilized by the combination of GRObeta and G-CSF. GRObeta-mobilized SKL cells demonstrate enhanced adherence to vascular cell adhesion molecule-1 and VCAM(pos) endothelial cells and home more efficiently to bone marrow in vivo. The marrow homing ability of GRObeta-mobilized cells is less dependent on the CXCR4/SDF-1 axis than cells mobilized by G-CSF. The mechanism of mobilization by GRObeta requires active matrix metalloproteinase-9 (MMP-9), which results from release of pro-MMP-9 from peripheral blood, and marrow neutrophils, which alters the stoichiometry between pro-MMP-9 and its inhibitor tissue inhibitor of metalloproteinase-1, resulting in MMP-9 activation. The efficacy and rapid action of GRObeta and lack of proinflammatory activity make it an attractive agent to supplement mobilization by G-CSF. In addition, GRObeta may also have clinical mobilizing efficacy on its own, reducing the overall time and costs associated with peripheral blood stem cell transplantation.

Cell surface glycan engineering of neural stem cells augments neurotropism and improves recovery in a murine model of multiple sclerosis.

PubMed

Merzaban, Jasmeen S; Imitola, Jaime; Starossom, Sarah C; Zhu, Bing; Wang, Yue; Lee, Jack; Ali, Amal J; Olah, Marta; Abuelela, Ayman F; Khoury, Samia J; Sackstein, Robert

2015-12-01

Neural stem cell (NSC)-based therapies offer potential for neural repair in central nervous system (CNS) inflammatory and degenerative disorders. Typically, these conditions present with multifocal CNS lesions making it impractical to inject NSCs locally, thus mandating optimization of vascular delivery of the cells to involved sites. Here, we analyzed NSCs for expression of molecular effectors of cell migration and found that these cells are natively devoid of E-selectin ligands. Using glycosyltransferase-programmed stereosubstitution (GPS), we glycan engineered the cell surface of NSCs ("GPS-NSCs") with resultant enforced expression of the potent E-selectin ligand HCELL (hematopoietic cell E-/L-selectin ligand) and of an E-selectin-binding glycoform of neural cell adhesion molecule ("NCAM-E"). Following intravenous (i.v.) injection, short-term homing studies demonstrated that, compared with buffer-treated (control) NSCs, GPS-NSCs showed greater neurotropism. Administration of GPS-NSC significantly attenuated the clinical course of experimental autoimmune encephalomyelitis (EAE), with markedly decreased inflammation and improved oligodendroglial and axonal integrity, but without evidence of long-term stem cell engraftment. Notably, this effect of NSC is not a universal property of adult stem cells, as administration of GPS-engineered mouse hematopoietic stem/progenitor cells did not improve EAE clinical course. These findings highlight the utility of cell surface glycan engineering to boost stem cell delivery in neuroinflammatory conditions and indicate that, despite the use of a neural tissue-specific progenitor cell population, neural repair in EAE results from endogenous repair and not from direct, NSC-derived cell replacement. © The Author 2015. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Defining a stem cell hierarchy in the intestine: markers, caveats and controversies

PubMed Central

Smith, Nicholas R.; Gallagher, Alexandra C.

2016-01-01

Abstract The past decade has appreciated rapid advance in identifying the once elusive intestinal stem cell (ISC) populations that fuel the continual renewal of the epithelial layer. This advance was largely driven by identification of novel stem cell marker genes, revealing the existence of quiescent, slowly‐ and active‐cycling ISC populations. However, a critical barrier for translating this knowledge to human health and disease remains elucidating the functional interplay between diverse stem cell populations. Currently, the precise hierarchical and regulatory relationships between these ISC populations are under intense scrutiny. The classical theory of a linear hierarchy, where quiescent and slowly‐cycling stem cells self‐renew but replenish an active‐cycling population, is well established in other rapidly renewing tissues such as the haematopoietic system. Efforts to definitively establish a similar stem cell hierarchy within the intestinal epithelium have yielded conflicting results, been difficult to interpret, and suggest non‐conventional alternatives to a linear hierarchy. While these new and potentially paradigm‐shifting discoveries are intriguing, the field will require development of a number of critical tools, including highly specific stem cell marker genes along with more rigorous experimental methodologies, to delineate the complex cellular relationships within this dynamic organ system. PMID:26864260

Lung Regeneration: Endogenous and Exogenous Stem Cell Mediated Therapeutic Approaches.

PubMed

Akram, Khondoker M; Patel, Neil; Spiteri, Monica A; Forsyth, Nicholas R

2016-01-19

The tissue turnover of unperturbed adult lung is remarkably slow. However, after injury or insult, a specialised group of facultative lung progenitors become activated to replenish damaged tissue through a reparative process called regeneration. Disruption in this process results in healing by fibrosis causing aberrant lung remodelling and organ dysfunction. Post-insult failure of regeneration leads to various incurable lung diseases including chronic obstructive pulmonary disease (COPD) and idiopathic pulmonary fibrosis. Therefore, identification of true endogenous lung progenitors/stem cells, and their regenerative pathway are crucial for next-generation therapeutic development. Recent studies provide exciting and novel insights into postnatal lung development and post-injury lung regeneration by native lung progenitors. Furthermore, exogenous application of bone marrow stem cells, embryonic stem cells and inducible pluripotent stem cells (iPSC) show evidences of their regenerative capacity in the repair of injured and diseased lungs. With the advent of modern tissue engineering techniques, whole lung regeneration in the lab using de-cellularised tissue scaffold and stem cells is now becoming reality. In this review, we will highlight the advancement of our understanding in lung regeneration and development of stem cell mediated therapeutic strategies in combating incurable lung diseases.

A Review of Human Pluripotent Stem Cell-Derived Cardiomyocytes for High-Throughput Drug Discovery, Cardiotoxicity Screening and Publication Standards

PubMed Central

Mordwinkin, Nicholas M.; Burridge, Paul W.; Wu, Joseph C.

2013-01-01

Drug attrition rates have increased in past years, resulting in growing costs for the pharmaceutical industry and consumers. The reasons for this include the lack of in vitro models that correlate with clinical results, and poor preclinical toxicity screening assays. The in vitro production of human cardiac progenitor cells and cardiomyocytes from human pluripotent stem cells provides an amenable source of cells for applications in drug discovery, disease modeling, regenerative medicine, and cardiotoxicity screening. In addition, the ability to derive human induced pluripotent stem cells from somatic tissues, combined with current high-throughput screening and pharmacogenomics, may help realize the use of these cells to fulfill the potential of personalized medicine. In this review, we discuss the use of pluripotent stem cell-derived cardiomyocytes for drug discovery and cardiotoxicity screening, as well as current hurdles that must be overcome for wider clinical applications of this promising approach. PMID:23229562

Induction of differentiation of human embryonic stem cells into functional hair-cell-like cells in the absence of stromal cells.

PubMed

Ding, Jie; Tang, Zihua; Chen, Jiarong; Shi, Haosong; Chen, Jianling; Wang, Cuicui; Zhang, Cui; Li, Liang; Chen, Ping; Wang, Jinfu

2016-12-01

Sensorineural hearing loss and vestibular dysfunction have become the most common forms of sensory defects. Stem cell-based therapeutic strategies for curing hearing loss are being developed. Several attempts to develop hair cells by using chicken utricle stromal cells as feeder cells have resulted in phenotypic conversion of stem cells into inner ear hair-cell-like cells. Here, we induced the differentiation of human embryonic stem cells (hESCs) into otic epithelial progenitors (OEPs), and further induced the differentiation of OEPs into hair-cell-like cells using different substrates. Our results showed that OEPs cultured on the chicken utricle stromal cells with the induction medium could differentiate into hair-cell-like cells with stereociliary bundles. Co-culture with stromal cells, however, may be problematic for subsequent examination of the induced hair-cell-like cells. In order to avoid the interference from stromal cells, we cultured OEPs on laminin with different induction media and examined the effects of the induction medium on the differentiation potentials of OEPs into hair-cell-like cells. The results revealed that the culture of OEPs on laminin with the conditioned medium from chicken utricle stromal cells supplemented with EGF and all-trans retinoic acid (RA) could promote the organization of cells into epithelial clusters displaying hair-cell-like cells with stereociliary bundles. These cells also displayed the expected electrophysiological properties. Copyright © 2015 Elsevier Ltd. All rights reserved.

Mitochondrial pyruvate carrier function determines cell stemness and metabolic reprogramming in cancer cells

PubMed Central

Li, Xiaoran; Kan, Quancheng; Fan, Zhirui; Li, Yaqing; Ji, Yasai; Zhao, Jing; Zhang, Mingzhi; Grigalavicius, Mantas; Berge, Viktor; Goscinski, Mariusz Adam; M. Nesland, Jahn; Suo, Zhenhe

2017-01-01

One of the remarkable features of cancer cells is aerobic glycolysis, a phenomenon known as the “Warburg Effect”, in which cells rely preferentially on glycolysis instead of oxidative phosphorylation (OXPHOS) as the main energy source even in the presence of high oxygen tension. Cells with dysfunctional mitochondria are unable to generate sufficient ATP from mitochondrial OXPHOS, and then are forced to rely on glycolysis for ATP generation. Here we report our results in a prostate cancer cell line in which the mitochondrial pyruvate carrier 1 (MPC1) gene was knockout. It was discovered that the MPC1 gene knockout cells revealed a metabolism reprogramming to aerobic glycolysis with reduced ATP production, and the cells became more migratory and resistant to both chemotherapy and radiotherapy. In addition, the MPC1 knockout cells expressed significantly higher levels of the stemness markers Nanog, Hif1α, Notch1, CD44 and ALDH. To further verify the correlation of MPC gene function and cell stemness/metabolic reprogramming, MPC inhibitor UK5099 was applied in two ovarian cancer cell lines and similar results were obtained. Taken together, our results reveal that functional MPC may determine the fate of metabolic program and the stemness status of cancer cells in vitro. PMID:28624784

New advances in stem cell research: practical implications for regenerative medicine.

PubMed

Ratajczak, Mariusz Z; Jadczyk, Tomasz; Pędziwiatr, Daniel; Wojakowski, Wojciech

2014-01-01

Regenerative medicine is searching for stem cells that can be safely and efficiently employed for regeneration of damaged solid organs (e.g., the heart, brain, or liver). Ideal for this purpose would be pluripotent stem cells, which, according to their definition, have broad potential to differentiate into all types of adult cells. For almost 20 years, there have been unsuccessful attempts to harness controversial embryonic stem cells (ESCs) isolated from embryos. Induced pluripotent stem cells (iPSCs), generated by genetic modification of adult somatic cells, are a more promising source. However, both iPSC and ESCs are associated with a risk of teratoma formation. At the same time, various types of more‑differentiated adult stem and progenitor cells derived from the bone marrow, umbilical cord blood, mobilized peripheral blood, or fat tissue are being employed in clinical trials to regenerate damaged solid organs. However, for most of these cells, there is a lack of convincing documentation for successful regeneration of the treated organs. Beneficial effects of those cells might be explained by paracrine effects of growth factors, cytokines, chemokines, bioactive lipids, and extracellular microvesicles, which are released from the cells and have trophic, antiapoptotic, and angiopoietic effects. Nevertheless, there is evidence that adult tissues harbor a promising population of very rare dormant stem cells with broad differentiation potential. In this review, we will discuss various potential sources of stem cells for regenerative medicine and the mechanisms that explain some of their beneficial effects as well as highlight the results of the first clinical trials.  

Efficient and rapid derivation of primitive neural stem cells and generation of brain subtype neurons from human pluripotent stem cells.

PubMed

Yan, Yiping; Shin, Soojung; Jha, Balendu Shekhar; Liu, Qiuyue; Sheng, Jianting; Li, Fuhai; Zhan, Ming; Davis, Janine; Bharti, Kapil; Zeng, Xianmin; Rao, Mahendra; Malik, Nasir; Vemuri, Mohan C

2013-11-01

Human pluripotent stem cells (hPSCs), including human embryonic stem cells and human induced pluripotent stem cells, are unique cell sources for disease modeling, drug discovery screens, and cell therapy applications. The first step in producing neural lineages from hPSCs is the generation of neural stem cells (NSCs). Current methods of NSC derivation involve the time-consuming, labor-intensive steps of an embryoid body generation or coculture with stromal cell lines that result in low-efficiency derivation of NSCs. In this study, we report a highly efficient serum-free pluripotent stem cell neural induction medium that can induce hPSCs into primitive NSCs (pNSCs) in 7 days, obviating the need for time-consuming, laborious embryoid body generation or rosette picking. The pNSCs expressed the neural stem cell markers Pax6, Sox1, Sox2, and Nestin; were negative for Oct4; could be expanded for multiple passages; and could be differentiated into neurons, astrocytes, and oligodendrocytes, in addition to the brain region-specific neuronal subtypes GABAergic, dopaminergic, and motor neurons. Global gene expression of the transcripts of pNSCs was comparable to that of rosette-derived and human fetal-derived NSCs. This work demonstrates an efficient method to generate expandable pNSCs, which can be further differentiated into central nervous system neurons and glia with temporal, spatial, and positional cues of brain regional heterogeneity. This method of pNSC derivation sets the stage for the scalable production of clinically relevant neural cells for cell therapy applications in good manufacturing practice conditions.

Perspectives on stem cell therapy for cardiac regeneration. Advances and challenges.

PubMed

Choi, Sung Hyun; Jung, Seok Yun; Kwon, Sang-Mo; Baek, Sang Hong

2012-01-01

Ischemic heart disease (IHD) accelerates cardiomyocyte loss, but the developing stem cell research could be useful for regenerating a variety of tissue cells, including cardiomyocytes. Diverse sources of stem cells for IHD have been reported, including embryonic stem cells, induced pluripotent stem cells, skeletal myoblasts, bone marrow-derived stem cells, mesenchymal stem cells, and cardiac stem cells. However, stem cells have unique advantages and disadvantages for cardiac tissue regeneration, which are important considerations in determining the specific cells for improving cell survival and long-term engraftment after transplantation. Additionally, the dosage and administration method of stem cells need to be standardized to increase stability and efficacy for clinical applications. Accordingly, this review presents a summary of the stem cell therapies that have been studied for cardiac regeneration thus far, and discusses the direction of future cardiac regeneration research for stem cells.

The Diverse Roles of Hydrogel Mechanics in Injectable Stem Cell Transplantation.

PubMed

Foster, Abbygail A; Marquardt, Laura M; Heilshorn, Sarah C

2017-02-01

Stem cell delivery by local injection has tremendous potential as a regenerative therapy but has seen limited clinical success. Several mechanical challenges hinder therapeutic efficacy throughout all stages of cell transplantation, including mechanical forces during injection and loss of mechanical support post-injection. Recent studies have begun exploring the use of biomaterials, in particular hydrogels, to enhance stem cell transplantation by addressing the often-conflicting mechanical requirements associated with each stage of the transplantation process. This review explores recent biomaterial approaches to improve the therapeutic efficacy of stem cells delivered through local injection, with a focus on strategies that specifically address the mechanical challenges that result in cell death and/or limit therapeutic function throughout the stages of transplantation.

Regulation of hematopoietic stem cell aging by the small RhoGTPase Cdc42

PubMed Central

Geiger, Hartmut; Zheng, Yi

2015-01-01

Summary Aging of stem cells might be the underlying cause of tissue aging in tissue that in the adult heavily rely on stem cell activity, like the blood forming system. Hematopoiesis, the generation of blood forming cells, is sustained by hematopoietic stem cells. In this review article, we introduce the canonical set of phenotypes associated with aged HSCs, focus on the novel aging-associated phenotype apolarity caused by elevated activity of the small RhoGTPase in aged HSCs, disuccs the role of Cdc42 in hematopoiesis and describe that pharmacological inhibition of Cdc42 activity in aged HSCs results in functionally young and thus rejuvenated HSCs. PMID:25220425

Stem Cells

MedlinePlus

Stem cells are cells with the potential to develop into many different types of cells in the body. They serve as a repair ... body. There are two main types of stem cells: embryonic stem cells and adult stem cells. Stem ...

In vitro proliferation and osteogenic differentiation of human dental pulp stem cells in injectable thermo-sensitive chitosan/β-glycerophosphate/hydroxyapatite hydrogel.

PubMed

Chen, Yantian; Zhang, Fengli; Fu, Qiang; Liu, Yong; Wang, Zejian; Qi, Nianmin

2016-09-01

Injectable thermo-sensitive hydrogels have a potential application in bone tissue engineering for their sensitivities and minimal invasive properties. Human dental pulp stem cells have been considered a promising tool for tissue reconstruction. The objective of this study was to investigate the proliferation and osteogenic differentiation of dental pulp stem cells in injectable thermo-sensitive chitosan/β-glycerophosphate/hydroxyapatite hydrogel in vitro. The chitosan /β-glycerophosphate hydrogel and chitosan/β-glycerophosphate/hydroxyapatite hydrogel were prepared using the sol-gel method. The injectability of chitosan /β-glycerophosphate hydrogel and chitosan/β-glycerophosphate/hydroxyapatite hydrogel was measured using a commercial disposable syringe. Scanning electron microscopy was used to observe the inner structure of hydrogels. Then dental pulp stem cells were seeded in chitosan /β-glycerophosphate hydrogel and chitosan/β-glycerophosphate/hydroxyapatite hydrogel, respectively. The growth of dental pulp stem cells was periodically observed under an inverted microscope. The proliferation of dental pulp stem cells was detected by using an Alamar Blue kit, while cell apoptosis was determined by using a Live/Dead Viability/Cytotoxicity kit. The osteogenic differentiations of dental pulp stem cells in chitosan /β-glycerophosphate hydrogel and chitosan/β-glycerophosphate/hydroxyapatite hydrogel were evaluated by alkaline phosphatase activity assay and mRNA expression of osteogenesis gene for 21 days in osteogenic medium. The results indicated that there was no significant difference between chitosan /β-glycerophosphate hydrogel and chitosan/β-glycerophosphate/hydroxyapatite hydrogel in injectability. Cells within the chitosan/β-glycerophosphate/hydroxyapatite hydrogel displayed a typical adherent cell morphology and rapid proliferation with high cellular viability after 14 days of culture. Dental pulp stem cells seeded in chitosan/β-glycerophosphate/hydroxyapatite hydrogels had a higher alkaline phosphatase activity and better up-regulation of gene expression levels of Runx-2, Collagen I, alkaline phosphatase and osteocalcin than in chitosan /β-glycerophosphate hydrogels after osteogenic differentiation. These results demonstrated that the chitosan/β-glycerophosphate/hydroxyapatite hydrogel had excellent cellular compatibility and the superiority in promoting dental pulp stem cells osteogenic differentiation in vitro, showing that the combination of dental pulp stem cells and chitosan/β-glycerophosphate/hydroxyapatite hydrogel has the potential to be used for bone tissue engineering. © The Author(s) 2016.

Establishment of mouse embryonic stem cells from isolated blastomeres and whole embryos using three derivation methods

PubMed Central

González, Sheyla; Ibáñez, Elena

2010-01-01

Purpose The aim of the present study is to compare three previously described mouse embryonic stem cell derivation methods to evaluate the influence of culture conditions, number of isolated blastomeres and embryonic stage in the derivation process. Methods Three embryonic stem cell derivation methods: standard, pre-adhesion and defined culture medium method, were compared in the derivation from isolated blastomeres and whole embryos at 4- and 8-cell stages. Results A total of 200 embryonic stem cell lines were obtained with an efficiency ranging from 1.9% to 72%. Conclusions Using either isolated blastomeres or whole embryos, the highest rates of mouse embryonic stem cell establishment were achieved with the defined culture medium method and efficiencies increased as development progressed. Using isolated blastomeres, efficiencies increased in parallel to the proportion of the embryo volume used to start the derivation process. PMID:20862536

Of mice and women: a comparative tissue biology perspective of breast stem cells and differentiation.

PubMed

Dontu, Gabriela; Ince, Tan A

2015-06-01

Tissue based research requires a background in human and veterinary pathology, developmental biology, anatomy, as well as molecular and cellular biology. This type of comparative tissue biology (CTB) expertise is necessary to tackle some of the conceptual challenges in human breast stem cell research. It is our opinion that the scarcity of CTB expertise contributed to some erroneous interpretations in tissue based research, some of which are reviewed here in the context of breast stem cells. In this article we examine the dissimilarities between mouse and human mammary tissue and suggest how these may impact stem cell studies. In addition, we consider the differences between breast ducts vs. lobules and clarify how these affect the interpretation of results in stem cell research. Lastly, we introduce a new elaboration of normal epithelial cell types in human breast and discuss how this provides a clinically useful basis for breast cancer classification.

Boron neutron capture therapy induces cell cycle arrest and cell apoptosis of glioma stem/progenitor cells in vitro

PubMed Central

2013-01-01

Background Glioma stem cells in the quiescent state are resistant to clinical radiation therapy. An almost inevitable glioma recurrence is due to the persistence of these cells. The high linear energy transfer associated with boron neutron capture therapy (BNCT) could kill quiescent and proliferative cells. Methods The present study aimed to evaluate the effects of BNCT on glioma stem/progenitor cells in vitro. The damage induced by BNCT was assessed using cell cycle progression, apoptotic cell ratio and apoptosis-associated proteins expression. Results The surviving fraction and cell viability of glioma stem/progenitor cells were decreased compared with differentiated glioma cells using the same boronophenylalanine pretreatment and the same dose of neutron flux. BNCT induced cell cycle arrest in the G2/M phase and cell apoptosis via the mitochondrial pathway, with changes in the expression of associated proteins. Conclusions Glioma stem/progenitor cells, which are resistant to current clinical radiotherapy, could be effectively killed by BNCT in vitro via cell cycle arrest and apoptosis using a prolonged neutron irradiation, although radiosensitivity of glioma stem/progenitor cells was decreased compared with differentiated glioma cells when using the same dose of thermal neutron exposure and boronophenylalanine pretreatment. Thus, BNCT could offer an appreciable therapeutic advantage to prevent tumor recurrence, and may become a promising treatment in recurrent glioma. PMID:23915425

Cell-Type-Specific Predictive Network Yields Novel Insights into Mouse Embryonic Stem Cell Self-Renewal and Cell Fate

PubMed Central

Dowell, Karen G.; Simons, Allen K.; Wang, Zack Z.; Yun, Kyuson; Hibbs, Matthew A.

2013-01-01

Self-renewal, the ability of a stem cell to divide repeatedly while maintaining an undifferentiated state, is a defining characteristic of all stem cells. Here, we clarify the molecular foundations of mouse embryonic stem cell (mESC) self-renewal by applying a proven Bayesian network machine learning approach to integrate high-throughput data for protein function discovery. By focusing on a single stem-cell system, at a specific developmental stage, within the context of well-defined biological processes known to be active in that cell type, we produce a consensus predictive network that reflects biological reality more closely than those made by prior efforts using more generalized, context-independent methods. In addition, we show how machine learning efforts may be misled if the tissue specific role of mammalian proteins is not defined in the training set and circumscribed in the evidential data. For this study, we assembled an extensive compendium of mESC data: ∼2.2 million data points, collected from 60 different studies, under 992 conditions. We then integrated these data into a consensus mESC functional relationship network focused on biological processes associated with embryonic stem cell self-renewal and cell fate determination. Computational evaluations, literature validation, and analyses of predicted functional linkages show that our results are highly accurate and biologically relevant. Our mESC network predicts many novel players involved in self-renewal and serves as the foundation for future pluripotent stem cell studies. This network can be used by stem cell researchers (at http://StemSight.org) to explore hypotheses about gene function in the context of self-renewal and to prioritize genes of interest for experimental validation. PMID:23468881

Combination therapy with carfilzomib, lenalidomide and dexamethasone (KRd) results in an unprecedented purity of the stem cell graft in newly diagnosed patients with myeloma.

PubMed

Tageja, Nishant; Korde, Neha; Kazandjian, Dickran; Panch, Sandhya; Manasanch, Elisabet; Bhutani, Manisha; Kwok, Mary; Mailankody, Sham; Yuan, Constance; Stetler-Stevenson, Maryalice; Leitman, Susan F; Sportes, Claude; Landgren, Ola

2018-05-04

Still, many physicians give 4 cycles of combination therapy to multiple myeloma patients prior to collection of stem cells for autologous bone marrow transplant. This tradition originates from older doxorubicin-containing regiments which limited the number of cycles due to cumulative cardiotoxicity. Using older regiments, most patients had residual myeloma cells in their autologous stem-cell grafts during collection. Emerging data show that newly diagnosed multiple myeloma patients treated with modern carfilzomib/lenalidomide/dexamethasone (KRd) therapy, on average, take 6 cycles until reaching minimal residual disease (MRD) negativity. We assessed newly diagnosed patients treated with KRd focusing MRD status both in the individual patient's bone marrow, and the corresponding autologous hematopoietic progenitor cell grafts during collection. Per protocol, stem-cell collection was allowed after 4 to 8 cycles of KRd. We found similar stem-cell yield independent of the number of cycles of KRd. At stem-cell collection, 11/30 patients (36.6%) were MRD negative in their bone marrow; all 11 patients had MRD negative hematopoietic progenitor cell grafts. Furthermore, 18/19 patients who were MRD positive in their bone marrows also had MRD negative hematopoietic progenitor cell grafts. These observations support 6 cycles of KRd as an efficacious and safe induction strategy prior to stem-cell collection.

A new method for cryopreserving adipose-derived stem cells: an attractive and suitable large-scale and long-term cell banking technology.

PubMed

De Rosa, Alfredo; De Francesco, Francesco; Tirino, Virginia; Ferraro, Giuseppe A; Desiderio, Vincenzo; Paino, Francesca; Pirozzi, Giuseppe; D'Andrea, Francesco; Papaccio, Gianpaolo

2009-12-01

Recent studies have shown potential ways for improving stem cell cryopreservation. The major need for autologous stem cell use is a long-term storage: this arises from the humans' hope of future use of their own cells. Therefore, it is important to evaluate the cell potential of vitality and differentiation before and after cryopreservation. Although several studies have shown a long-term preservation of adipose tissue, a few of them focused their attention to stem cells. The aim of this study was to evaluate the fate of cryopreserved stem cells collected from adipose tissue and stored at low a temperature in liquid nitrogen through an optimal cryopreservation solution (using slowly cooling in 6% threalose, 4% dimethyl sulfoxide, and 10% fetal bovine serum) and to develop a novel approach to efficiently preserve adipose-derived stem cells (ASCs) for future clinical applications. Results showed that stem cells, after being thawed, are still capable of differentiation and express all surface antigens detected before storage, confirming the integrity of their biology. In particular, ASCs differentiated into adipocytes, showed diffuse positivity for PPARgamma and adiponectin, and were also able to differentiate into endothelial cells without addition of angiogenic factors. Therefore, ASCs can be long-term cryopreserved, and this, due to their great numbers, is an attractive tool for clinical applications as well as of impact for the derived market.

Biocompatibility of quantum dots (CdSe/ZnS ) in human amniotic membrane-derived mesenchymal stem cells in vitro.

PubMed

Wang, Gongping; Zeng, Guangwei; Wang, Caie; Wang, Huasheng; Yang, Bo; Guan, Fangxia; Li, Dongpeng; Feng, Xiaoshan

2015-06-01

Amniotic membrane-derived mesenchymal stem cells (hAM-dMSCs) are a potential source of mesenchymal stem cells which could be used to repair skin damage. The use of mesenchymal stem cells to repair skin damage requires safe, effective and biocompatible agents to evaluate the effectiveness of the result. Quantum dots (QDs) composed of CdSe/ZnS are semiconductor nanocrystals with broad excitation and narrow emission spectra, which have been considered as a new chemical and fluorescent substance for non-invasively labeling different cells in vitro and in vivo. This study investigated the cytotoxic effects of QDs on hAM-dMSCs at different times following labeling. Using 0.75, 1.5 and 3.0 μL between quantum dots, labeled human amniotic mesenchymal stem cells were collected on days 1, 2 and 4 and observed morphological changes, performed an MTT cell growth assay and flow cytometry for mesenchymal stem cells molecular markers. Quantum dot concentration 0.75 μg/mL labeled under a fluorescence microscope, cell morphology was observed, The MTT assay showed cells in the proliferative phase. Flow cytometry expression CD29, CD31, CD34, CD44, CD90, CD105 and CD106. Within a certain range of concentrations between quantum dots labeled human amniotic mesenchymal stem cells has good biocompatibility.

Human cadaver multipotent stromal/stem cells isolated from arteries stored in liquid nitrogen for 5 years

PubMed Central

2014-01-01

Introduction Regenerative medicine challenges researchers to find noncontroversial, safe and abundant stem cell sources. In this context, harvesting from asystolic donors could represent an innovative and unlimited reservoir of different stem cells. In this study, cadaveric vascular tissues were established as an alternative source of human cadaver mesenchymal stromal/stem cells (hC-MSCs). We reported the successful cell isolation from postmortem arterial segments stored in a tissue-banking facility for at least 5 years. Methods After thawing, hC-MSCs were isolated with a high efficiency (12 × 106) and characterized with flow cytometry, immunofluorescence, molecular and ultrastructural approaches. Results In early passages, hC-MSCs were clonogenic, highly proliferative and expressed mesenchymal (CD44, CD73, CD90, CD105, HLA-G), stemness (Stro-1, Oct-4, Notch-1), pericyte (CD146, PDGFR-β, NG2) and neuronal (Nestin) markers; hematopoietic and vascular markers were negative. These cells had colony and spheroid-forming abilities, multipotency for their potential to differentiate in multiple mesengenic lineages and immunosuppressive activity to counteract proliferation of phytohemagglutinin-stimulated blood mononuclear cells. Conclusions The efficient procurement of stem cells from cadaveric sources, as postmortem vascular tissues, demonstrates that such cells can survive to prolonged ischemic insult, anoxia, freezing and dehydration injuries, thus paving the way for a scientific revolution where cadaver stromal/stem cells could effectively treat patients demanding cell therapies. PMID:24429026

The Role of Integrin α6 (CD49f) in Stem Cells: More than a Conserved Biomarker.

PubMed

Krebsbach, Paul H; Villa-Diaz, Luis G

2017-08-01

Stem cells have the capacity for self-renewal and differentiation into specialized cells that form and repopulated all tissues and organs, from conception to adult life. Depending on their capacity for differentiation, stem cells are classified as totipotent (ie, zygote), pluripotent (ie, embryonic stem cells), multipotent (ie, neuronal stem cells, hematopoietic stem cells, epithelial stem cells, etc.), and unipotent (ie, spermatogonial stem cells). Adult or tissue-specific stem cells reside in specific niches located in, or nearby, their organ or tissue of origin. There, they have microenvironmental support to remain quiescent, to proliferate as undifferentiated cells (self-renewal), and to differentiate into progenitors or terminally differentiated cells that migrate from the niche to perform specialized functions. The presence of proteins at the cell surface is often used to identify, classify, and isolate stem cells. Among the diverse groups of cell surface proteins used for these purposes, integrin α6, also known as CD49f, may be the only biomarker commonly found in more than 30 different populations of stem cells, including some cancer stem cells. This broad expression among stem cell populations indicates that integrin α6 may play an important and conserved role in stem cell biology, which is reaffirmed by recent demonstrations of its role maintaining self-renewal of pluripotent stem cells and breast and glioblastoma cancer stem cells. Therefore, this review intends to highlight and synthesize new findings on the importance of integrin α6 in stem cell biology.

Morphological description of limbal epithelium: searching for stem cells crypts in the dog, cat, pig, cow, sheep and horse.

PubMed

Patruno, M; Perazzi, A; Martinello, T; Blaseotto, A; Di Iorio, E; Iacopetti, I

2017-06-01

The cornea provides protection and transparency to the eye, allowing an optimal sharpness view. In some pathological conditions the cornea is able to regenerate thanks to the presence of a stem cells reservoir present at the level of the transition area between cornea and sclera (limbus). Corneal cell therapies in Veterinary Medicine are really limited due to the lacking of knowledge about the anatomy of the limbal area, the putative presence of stem cells and their identification in domestic species. The aim of this study was to provide an overview of the main distinctive structural features of the sclero-corneal junction and conjunctival-corneal junction areas in some species of veterinary importance, using optic microscope observations of histological sections. The resulting data were compared with cornea from humans adapting protocols already used to identify stem cells by means of a specific cellular marker. We tested the expression of ΔNp63α isoform in the cornea basal cells, trying to correlate the distribution profile with areas of highly proliferative turnover. The results obtained from this study represent a first step towards the identification of a corneal stem cells reservoir in different animals.

A novel long non-coding RNA, hypoxia-inducible factor-2α promoter upstream transcript, functions as an inhibitor of osteosarcoma stem cells in vitro.

PubMed

Wang, Yongcheng; Yao, Jie; Meng, Haoye; Yu, Zhiguo; Wang, Zhigang; Yuan, Xueling; Chen, Hong; Wang, Aiyuan

2015-04-01

Long non‑coding RNAs (lncRNAs) have recently been identified as novel modulators of malignant tumors. However, the function of lncRNAs in cancer stem cells (CSCs) remains to be elucidated. The present study aimed to investigate the regulating role of a novel lncRNA, hypoxia‑inducible factor‑2α (HIF‑2α) promoter upstream transcript (HIF2PUT), in osteosarcoma stem cells. The expression levels of HIF2PUT were assessed by quantitative polymerase chain reaction in 17 osteosarcoma tissue specimens, and the correlation between the expression of HIF2PUT and its host transcript‑HIF‑2α was determined. In functional experiments, HIF2PUT expression was knocked down by small interfering RNAs, or overexpressed by transfection with pcDNA‑HIF2PUT, in order to evaluate the effects of HIF2PUT on cell proliferation, migration, expression rate of osteosarcoma stem cell marker CD133, and stem sphere‑forming ability in MG63 cells. HIF2PUT expression levels were positively correlated with HIF‑2α in osteosarcoma tissues. Overexpression of HIF2PUT markedly inhibited cell proliferation and migration, decreased the percentage of CD133 expressing cells, and impaired the osteosarcoma stem sphere‑forming ability of the MG63 cells. Whereas, knockdown of HIF2PUT expression had the opposite effect. Furthermore, altering the expression of HIF2PUT resulted in a concomitant change to HIF‑2α mRNA expression. These results indicate that the lncRNA HIF2PUT may be a novel regulatory factor of osteosarcoma stem cells, which may exert its function partly by controlling HIF‑2α expression. Further studies regarding HIF2PUT may provide a novel therapeutic target of osteosarcoma in the future.

Disruption of the actin cytoskeleton results in the promotion of gravitropism in inflorescence stems and hypocotyls of Arabidopsis

NASA Technical Reports Server (NTRS)

Yamamoto, Kazuyoshi; Kiss, John Z.

2002-01-01

The actin cytoskeleton is hypothesized to play a major role in gravity perception and transduction mechanisms in roots of plants. To determine whether actin microfilaments (MFs) are involved in these processes in stem-like organs, we studied gravitropism in Arabidopsis inflorescence stems and hypocotyls. Localization studies using Alexa Fluor-phalloidin in conjugation with confocal microscopy demonstrated a longitudinally and transversely oriented actin MF network in endodermal cells of stems and hypocotyls. Latrunculin B (Lat-B) treatment of hypocotyls caused depolymerization of actin MFs in endodermal cells and a significant reduction of hypocotyl growth rates. Actin MFs in Lat-B-treated inflorescence stems also were disrupted, but growth rates were not affected. Despite disruption of the actin cytoskeleton in these two organs, Lat-B-treated stems and hypocotyls exhibited a promotion of gravitropic curvature in response to reorientation. In contrast, Lat-B reduced gravitropic curvature in roots but also reduced the growth rate. Thus, in contrast to prevailing hypotheses, our results suggest that actin MFs are not a necessary component of gravitropism in inflorescence stems and hypocotyls. Furthermore, this is the first study to demonstrate a prominent actin MF network in endodermal cells in the putative gravity-perceiving cells in stems.

Disruption of the Actin Cytoskeleton Results in the Promotion of Gravitropism in Inflorescence Stems and Hypocotyls of Arabidopsis1

PubMed Central

Yamamoto, Kazuyoshi; Kiss, John Z.

2002-01-01

The actin cytoskeleton is hypothesized to play a major role in gravity perception and transduction mechanisms in roots of plants. To determine whether actin microfilaments (MFs) are involved in these processes in stem-like organs, we studied gravitropism in Arabidopsis inflorescence stems and hypocotyls. Localization studies using Alexa Fluor-phalloidin in conjugation with confocal microscopy demonstrated a longitudinally and transversely oriented actin MF network in endodermal cells of stems and hypocotyls. Latrunculin B (Lat-B) treatment of hypocotyls caused depolymerization of actin MFs in endodermal cells and a significant reduction of hypocotyl growth rates. Actin MFs in Lat-B-treated inflorescence stems also were disrupted, but growth rates were not affected. Despite disruption of the actin cytoskeleton in these two organs, Lat-B-treated stems and hypocotyls exhibited a promotion of gravitropic curvature in response to reorientation. In contrast, Lat-B reduced gravitropic curvature in roots but also reduced the growth rate. Thus, in contrast to prevailing hypotheses, our results suggest that actin MFs are not a necessary component of gravitropism in inflorescence stems and hypocotyls. Furthermore, this is the first study to demonstrate a prominent actin MF network in endodermal cells in the putative gravity-perceiving cells in stems. PMID:11842170

Pretreatment of Adipose Derived Stem Cells with Curcumin Facilitates Myocardial Recovery via Antiapoptosis and Angiogenesis

PubMed Central

Liu, Jianfeng; Zhu, Ping; Song, Peng; Xiong, Weiping; Chen, Haixu; Peng, Wenhui; Wang, Shuxia; Li, Shan; Fu, Zhiqing; Wang, Yutang; Wang, Haibin

2015-01-01

The poor survival rate of transplanted stem cells in ischemic myocardium has limited their therapeutic efficacy. Curcumin has potent antioxidant property. This study investigates whether prior curcumin treatment protects stem cells from oxidative stress injury and improves myocardial recovery following cells transplantation. Autologous Sprague-Dawley rat adipose derived mesenchymal stem cells (ADSCs) were pretreated with or without curcumin. The hydrogen peroxide/serum deprivation (H2O2/SD) medium was used to mimic the ischemic condition in vitro. Cytoprotective effects of curcumin on ADSCs were evaluated. Curcumin pretreatment significantly increased cell viability and VEGF secretion, and decreased cell injury and apoptosis via regulation of PTEN/Akt/p53 and HO-1 signal proteins expression. The therapeutic potential of ADSCs implantation was investigated in myocardial ischemia-reperfusion injury (IRI) model. Transplantation of curcumin pretreated ADSCs not only resulted in better heart function, higher cells retention, and smaller infarct size, but also decreased myocardial apoptosis, promoted neovascularization, and increased VEGF level in ischemic myocardium. Together, priming of ADSCs with curcumin improved tolerance to oxidative stress injury and resulted in enhancement of their therapeutic potential of ADSCs for myocardial repair. Curcumin pretreatment is a promising adjuvant strategy for stem cells transplantation in myocardial restoration. PMID:26074974

[PML-RARα and p21 are key factors for maintaining acute promyelocytic leukemia stem cells survival].

PubMed

Ding, Fei; Li, Jun-Min

2011-10-01

Tumor stem/progenitor cells are the cells with the characteristics of self-renewal, differentiating to all the other cell populations within tumor, which are also regarded as the source of tumor relapse, drug-resistance and metastasis. As a subtype of acute myeloid leukemia, acute promyelocytic leukemia (APL) represents the target of therapy due to the good response of the oncogenic protein PML-RARα to all-trans retinoic acid (ATRA) and arsenic trioxide (ATO). This review summarizes the latest research results of APL as follows: (1) there probably are two APL stem/progenitor cell populations within APL, and self-renewal and survival of APL stem/progenitor cells highly depend on PML-RARα expression, cell cycle inhibitor p21, self-renewal associated molecules and chemokines; and (2) ATRA and ATO eradicate APL stem/progenitor cells mainly by PML-RARα degradation, FOXO3A activation and the inhibition of self-renewal-associated signaling pathway of sonic hedgehog. These findings are helpful to improve other tumor therapy.

Transcriptional and Cell Cycle Alterations Mark Aging of Primary Human Adipose-Derived Stem Cells.

PubMed

Shan, Xiaoyin; Roberts, Cleresa; Kim, Eun Ji; Brenner, Ariana; Grant, Gregory; Percec, Ivona

2017-05-01

Adult stem cells play a critical role in the maintenance of tissue homeostasis and prevention of aging. While the regenerative potential of stem cells with low cellular turnover, such as adipose-derived stem cells (ASCs), is increasingly recognized, the study of chronological aging in ASCs is technically difficult and remains poorly understood. Here, we use our model of chronological aging in primary human ASCs to examine genome-wide transcriptional networks. We demonstrate first that the transcriptome of aging ASCs is distinctly more stable than that of age-matched fibroblasts, and further, that age-dependent modifications in cell cycle progression and translation initiation specifically characterize aging ASCs in conjunction with increased nascent protein synthesis and a distinctly shortened G1 phase. Our results reveal novel chronological aging mechanisms in ASCs that are inherently different from differentiated cells and that may reflect an organismal attempt to meet the increased demands of tissue and organ homeostasis during aging. Stem Cells 2017;35:1392-1401. © 2017 AlphaMed Press.

CD133 Is Not Suitable Marker for Isolating Melanoma Stem Cells from D10 Cell Line.

PubMed

Rajabi Fomeshi, Motahareh; Ebrahimi, Marzieh; Mowla, Seyed Javad; Firouzi, Javad; Khosravani, Pardis

2016-01-01

Cutaneous melanoma is the most hazardous malignancy of skin cancer with a high mortality rate. It has been reported that cancer stem cells (CSCs) are responsible for malignancy in most of cancers including melanoma. The aim of this study is to compare two common methods for melanoma stem cell enriching; isolating based on the CD133 cell surface marker and spheroid cell culture. In this experimental study, melanoma stem cells were enriched by fluorescence activated cell sorting (FACS) based on the CD133 protein expression and spheroid culture of D10 melanoma cell line,. To determine stemness features, the mRNA expression analysis of ABCG2, c-MYC, NESTIN, OCT4-A and -B genes as well as colony and spheroid formation assays were utilized in unsorted CD133(+), CD133(-) and spheroid cells. Significant differences of the two experimental groups were compared using student's t tests and a two-tailed value of P<0.05 was statistically considered as a significant threshold. Our results demonstrated that spheroid cells had more colony and spheroid forming ability, rather than CD133(+) cells and the other groups. Moreover, melanospheres expressed higher mRNA expression level of ABCG2, c-MYC, NESTIN and OCT4-A com- pared to other groups (P<0.05). Although CD133(+) derived melanoma cells represented stemness fea- tures, our findings demonstrated that spheroid culture could be more effective meth- od to enrich melanoma stem cells.

Application of stem cell-derived retinal pigmented epithelium in retinal degenerative diseases: present and future.

PubMed

Luo, Mingyue; Chen, Youxin

2018-01-01

As a constituent of blood-retinal barrier and retinal outer segment (ROS) scavenger, retinal pigmented epithelium (RPE) is fundamental to normal function of retina. Malfunctioning of RPE contributes to the onset and advance of retinal degenerative diseases. Up to date, RPE replacement therapy is the only possible method to completely reverse retinal degeneration. Transplantation of human RPE stem cell-derived RPE (hRPESC-RPE) has shown some good results in animal models. With promising results in terms of safety and visual improvement, human embryonic stem cell-derived RPE (hESC-RPE) can be expected in clinical settings in the near future. Despite twists and turns, induced pluripotent stem cell-derived RPE (iPSC-RPE) is now being intensely investigated to overcome genetic and epigenetic instability. By far, only one patient has received iPSC-RPE transplant, which is a hallmark of iPSC technology development. During follow-up, no major complications such as immunogenicity or tumorigenesis have been observed. Future trials should keep focusing on the safety of stem cell-derived RPE (SC-RPE) especially in long period, and better understanding of the nature of stem cell and the molecular events in the process to generate SC-RPE is necessary to the prosperity of SC-RPE clinical application.

Porous microscaffolds for 3D culture of dental pulp mesenchymal stem cells.

PubMed

Bhuptani, Ronak S; Patravale, Vandana B

2016-12-30

The collective power of stem cells due to their evident advantages is incessantly investigated in regenerative medicine to be the next generation exceptional remedy for tissue regeneration and treatment of diseases. Stem cells are highly sensitive and a 3D culture environment is a requisite for its successful transplantation and integration with tissues. Porous microscaffolds can create a 3D microenvironment for growing stems cells, controlling their fate both in vitro and in vivo. In the present study, interconnected porous PLGA microscaffolds were fabricated, characterized and employed to propagate human dental pulp mesenchymal stem cells (DPMSCs) in vitro. The porous topography was investigated by scanning electron microscopy and the pore size was controlled by fabrication conditions such as the concentration of porogen. DPMSCs were cultured on microscaffolds and were evaluated for their morphology, attachment, proliferation, cell viability via MTT and molecular expression (RT-PCR). DPMSCs were adequately proliferated and adhered over the microscaffolds forming a 3D cell-microscaffold construct. The average number of DPMSCs grown on PLGA microscaffolds was significantly higher than monolayer 2D culture during 5th and 7th day. Moreover, cell viability and gene expression results together corroborated that microscaffolds maintained the viability, stemness and plasticity of the cultured dental pulp mesenchymal stem cells. The novel porous microscaffold developed acts as promising scaffold for 3D culture and survival and transplantation of stem cells for tissue engineering. Copyright © 2016 Elsevier B.V. All rights reserved.

Phenformin-loaded polymeric micelles for targeting both cancer cells and cancer stem cells in vitro and in vivo.

PubMed

Krishnamurthy, Sangeetha; Ng, Victor W L; Gao, Shujun; Tan, Min-Han; Yang, Yi Yan

2014-11-01

Conventional cancer chemotherapy often fails as most anti-cancer drugs are not effective against drug-resistant cancer stem cells. These surviving cancer stem cells lead to relapse and metastasis. In this study, an anti-diabetic drug, phenformin, capable of eliminating cancer stem cells was loaded into micelles via self-assembly using a mixture of a diblock copolymer of poly(ethylene glycol) (PEG) and urea-functionalized polycarbonate and a diblock copolymer of PEG and acid-functionalized polycarbonate through hydrogen bonding. The phenformin-loaded micelles, having an average diameter of 102 nm with narrow size distribution, were stable in serum-containing solution over 48 h and non-cytotoxic towards non-cancerous cells. More than 90% of phenformin was released from the micelles over 96 h. Lung cancer stem cells (side population cells, i.e. SP cells) and non-SP cells were sorted from H460 human lung cancer cell line, and treated with free phenformin and phenformin-loaded micelles. The results showed that the drug-loaded micelles were more effective in inhibiting the growth of both SP and non-SP cells. In vivo studies conducted in an H460 human lung cancer mouse model demonstrated that the drug-loaded micelles had greater anti-tumor efficacy, and reduced the population of SP cells in the tumor tissues more effectively than free phenformin. Liver function analysis was performed following drug treatments, and the results indicated that the drug-loaded micelles did not cause liver damage, a harmful side-effect of phenformin when used clinically. These phenformin-loaded micelles may be used to target both cancer cells and cancer stem cells in chemotherapy for the prevention of relapse and metastasis. Copyright © 2014 Elsevier Ltd. All rights reserved.

Targeting stemness is an effective strategy to control EML4-ALK+ non-small cell lung cancer cells

PubMed Central

Oh, Se Jin; Noh, Kyung Hee; Lee, Young-Ho; Hong, Soon-Oh; Song, Kwon-Ho; Lee, Hyo-Jung; Kim, Soyeon; Kim, Tae Min; Jeon, Ju-Hong; Seo, Jae Hong; Kim, Dong-Wan; Kim, Tae Woo

2015-01-01

The fusion between anaplastic lymphoma kinase (ALK) and echinoderm microtubule-associated protein-like 4 (EML4) is a causative factor in a unique subset of patients with non-small cell lung carcinoma (NSCLC). Although the inhibitor crizotinib, as it blocks the kinase activity of the resulting EML4-ALK fusion protein, displays remarkable initial responses, a fraction of NSCLC cases eventually become resistant to crizotinib by acquiring mutations in the ALK domain or activating bypass pathways via EGFR, KIT, or KRAS. Cancer stem cell (CSC) theory provides a plausible explanation for acquisition of tumorigenesis and resistance. However, the question as to whether EML4-ALK-driven tumorigenesis is linked with the stem-like property and whether the stemness is an effective target in controlling EML4-ALK+ NSCLC including crizotinib-resistant NSCLC cells has not been addressed. Here, we report that stem-like properties stem from ALK activity in EML4-ALK+ NSCLC cells. Notably, treatment with rapamycin, a CSC targeting agent, attenuates stem-like phenotypes of the EML4-ALK+ cells, which increased capability of tumor formation and higher expression of stemness-associated molecules such as ALDH, NANOG, and OCT4. Importantly, combinational treatment with rapamycin and crizotinib leads to synergistic anti-tumor effects on EML4-ALK+ NSCLC cells as well as on those resistant to crizotinib. Thus, we provide a proof of principle that targeting stemness would be a novel strategy to control intractable EML4-ALK+ NSCLC. PMID:26517679

Targeting stemness is an effective strategy to control EML4-ALK+ non-small cell lung cancer cells.

PubMed

Oh, Se Jin; Noh, Kyung Hee; Lee, Young-Ho; Hong, Soon-Oh; Song, Kwon-Ho; Lee, Hyo-Jung; Kim, Soyeon; Kim, Tae Min; Jeon, Ju-Hong; Seo, Jae Hong; Kim, Dong-Wan; Kim, Tae Woo

2015-11-24

The fusion between anaplastic lymphoma kinase (ALK) and echinoderm microtubule-associated protein-like 4 (EML4) is a causative factor in a unique subset of patients with non-small cell lung carcinoma (NSCLC). Although the inhibitor crizotinib, as it blocks the kinase activity of the resulting EML4-ALK fusion protein, displays remarkable initial responses, a fraction of NSCLC cases eventually become resistant to crizotinib by acquiring mutations in the ALK domain or activating bypass pathways via EGFR, KIT, or KRAS. Cancer stem cell (CSC) theory provides a plausible explanation for acquisition of tumorigenesis and resistance. However, the question as to whether EML4-ALK-driven tumorigenesis is linked with the stem-like property and whether the stemness is an effective target in controlling EML4-ALK+ NSCLC including crizotinib-resistant NSCLC cells has not been addressed. Here, we report that stem-like properties stem from ALK activity in EML4-ALK+ NSCLC cells. Notably, treatment with rapamycin, a CSC targeting agent, attenuates stem-like phenotypes of the EML4-ALK+ cells, which increased capability of tumor formation and higher expression of stemness-associated molecules such as ALDH, NANOG, and OCT4. Importantly, combinational treatment with rapamycin and crizotinib leads to synergistic anti-tumor effects on EML4-ALK+ NSCLC cells as well as on those resistant to crizotinib. Thus, we provide a proof of principle that targeting stemness would be a novel strategy to control intractable EML4-ALK+ NSCLC.

A PITX3-EGFP Reporter Line Reveals Connectivity of Dopamine and Non-dopamine Neuronal Subtypes in Grafts Generated from Human Embryonic Stem Cells.

PubMed

Niclis, Jonathan C; Gantner, Carlos W; Hunt, Cameron P J; Kauhausen, Jessica A; Durnall, Jennifer C; Haynes, John M; Pouton, Colin W; Parish, Clare L; Thompson, Lachlan H

2017-09-12

Development of safe and effective stem cell-based therapies for brain repair requires an in-depth understanding of the in vivo properties of neural grafts generated from human stem cells. Replacing dopamine neurons in Parkinson's disease remains one of the most anticipated applications. Here, we have used a human PITX3-EGFP embryonic stem cell line to characterize the connectivity of stem cell-derived midbrain dopamine neurons in the dopamine-depleted host brain with an unprecedented level of specificity. The results show that the major A9 and A10 subclasses of implanted dopamine neurons innervate multiple, developmentally appropriate host targets but also that the majority of graft-derived connectivity is non-dopaminergic. These findings highlight the promise of stem cell-based procedures for anatomically correct reconstruction of specific neuronal pathways but also emphasize the scope for further refinement in order to limit the inclusion of uncharacterized and potentially unwanted cell types. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

Silk fibroin/chitosan thin film promotes osteogenic and adipogenic differentiation of rat bone marrow-derived mesenchymal stem cells.

PubMed

Li, Da-Wei; He, Jin; He, Feng-Li; Liu, Ya-Li; Liu, Yang-Yang; Ye, Ya-Jing; Deng, Xudong; Yin, Da-Chuan

2018-04-01

As a biodegradable polymer thin film, silk fibroin/chitosan composite film overcomes the defects of pure silk fibroin and chitosan films, respectively, and shows remarkable biocompatibility, appropriate hydrophilicity and mechanical properties. Silk fibroin/chitosan thin film can be used not only as metal implant coating for bone injury repair, but also as tissue engineering scaffold for skin, cornea, adipose, and other soft tissue injury repair. However, the biocompatibility of silk fibroin/chitosan thin film for mesenchymal stem cells, a kind of important seed cell of tissue engineering and regenerative medicine, is rarely reported. In this study, silk fibroin/chitosan film was prepared by solvent casting method, and the rat bone marrow-derived mesenchymal stem cells were cultured on the silk fibroin/chitosan thin film. Osteogenic and adipogenic differentiation of rat bone marrow-derived mesenchymal stem cells were induced, respectively. The proliferation ability, osteogenic and adipogenic differentiation abilities of rat bone marrow-derived mesenchymal stem cells were systematically compared between silk fibroin/chitosan thin film and polystyrene tissue culture plates. The results showed that silk fibroin/chitosan thin film not only provided a comparable environment for the growth and proliferation of rat bone marrow-derived mesenchymal stem cells but also promoted their osteogenic and adipogenic differentiation. This work provided information of rat bone marrow-derived mesenchymal stem cells behavior on silk fibroin/chitosan thin film and extended the application of silk fibroin/chitosan thin film. Based on the results, we suggested that the silk fibroin/chitosan thin film could be a promising material for tissue engineering of bone, cartilage, adipose, and skin.

Molecular Programs Underlying Asymmetric Stem Cell Division and Their Disruption in Malignancy.

PubMed

Mukherjee, Subhas; Brat, Daniel J

2017-01-01

Asymmetric division of stem cells is a highly conserved and tightly regulated process by which a single stem cell produces two unequal daughter cells. One retains its stem cell identity while the other becomes specialized through a differentiation program and loses stem cell properties. Coordinating these events requires control over numerous intra- and extracellular biological processes and signaling networks. In the initial stages, critical events include the compartmentalization of fate determining proteins within the mother cell and their subsequent passage to the appropriate daughter cell in order to direct their destiny. Disturbance of these events results in an altered dynamic of self-renewing and differentiation within the cell population, which is highly relevant to the growth and progression of cancer. Other critical events include proper asymmetric spindle assembly, extrinsic regulation through micro-environmental cues, and non-canonical signaling networks that impact cell division and fate determination. In this review, we discuss mechanisms that maintain the delicate balance of asymmetric cell division in normal tissues and describe the current understanding how some of these mechanisms are deregulated in cancer.

Short-term application of dexamethasone on stem cells derived from human gingiva reduces the expression of RUNX2 and β-catenin.

PubMed

Kim, Bo-Bae; Kim, Minji; Park, Yun-Hee; Ko, Youngkyung; Park, Jun-Beom

2017-06-01

Objective Next-generation sequencing was performed to evaluate the effects of short-term application of dexamethasone on human gingiva-derived mesenchymal stem cells. Methods Human gingiva-derived stem cells were treated with a final concentration of 10 -7  M dexamethasone and the same concentration of vehicle control. This was followed by mRNA sequencing and data analysis, gene ontology and pathway analysis, quantitative real-time polymerase chain reaction of mRNA, and western blot analysis of RUNX2 and β-catenin. Results In total, 26,364 mRNAs were differentially expressed. Comparison of the results of dexamethasone versus control at 2 hours revealed that 7 mRNAs were upregulated and 25 mRNAs were downregulated. The application of dexamethasone reduced the expression of RUNX2 and β-catenin in human gingiva-derived mesenchymal stem cells. Conclusion The effects of dexamethasone on stem cells were evaluated with mRNA sequencing, and validation of the expression was performed with qualitative real-time polymerase chain reaction and western blot analysis. The results of this study can provide new insights into the role of mRNA sequencing in maxillofacial areas.