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Sample records for normal stem cells

  1. Stem cells in normal mammary gland and breast cancer.

    PubMed

    Luo, Jie; Yin, Xin; Ma, Tao; Lu, Jun

    2010-04-01

    The mammary gland is a structurally dynamic organ that undergoes dramatic alterations with age, menstrual cycle, and reproductive status. Mammary gland stem cells, the minor cell population within the mature organ, are thought to have multiple functions in regulating mammary gland development, tissue maintenance, major growth, and structural remodeling. In addition, accumulative evidence suggests that breast cancers are initiated and maintained by a subpopulation of tumor cells with stem cell features (called cancer stem cells). A variety of methods have been developed to identify and characterize mammary stem cells, and several signal transduction pathways have been identified to be essential for the self-renewal and differentiation of mammary gland stem cells. Understanding the origin of breast cancer stem cells, their relationship to breast cancer development, and the differences between normal and cancer stem cells may lead to novel approaches to breast cancer diagnosis, prevention, and treatment.

  2. Reactive Oxygen Species in Normal and Tumor Stem Cells

    PubMed Central

    Zhou, Daohong; Shao, Lijian; Spitz, Douglas R.

    2014-01-01

    Reactive oxygen species (ROS) play an important role in determining the fate of normal stem cells. Low levels of ROS are required for stem cells to maintain quiescence and self-renewal. Increases in ROS production cause stem cell proliferation/differentiation, senescence, and apoptosis in a dose-dependent manner, leading to their exhaustion. Therefore, the production of ROS in stem cells is tightly regulated to ensure that they have the ability to maintain tissue homeostasis and repair damaged tissues for the life span of an organism. In this chapter, we discuss how the production of ROS in normal stem cells is regulated by various intrinsic and extrinsic factors and how the fate of these cells is altered by the dysregulation of ROS production under various pathological conditions. In addition, the implications of the aberrant production of ROS by tumor stem cells for tumor progression and treatment are also discussed. PMID:24974178

  3. Normal and Leukemic Stem Cell Niches: Insights and Therapeutic Opportunities

    PubMed Central

    Schepers, Koen; Campbell, Timothy B.; Passegué, Emmanuelle

    2015-01-01

    Hematopoietic stem cells (HSC) rely on instructive cues from the bone marrow (BM) niche to maintain their quiescence and adapt blood production to the organism’s needs. Alterations in the BM niche are commonly observed in blood malignancies and directly contribute to the aberrant function of disease-initiating leukemic stem cells (LSC). Here, we review recent insights into the cellular and molecular determinants of the normal HSC niche and describe how genetic changes in stromal cells and leukemia-induced BM niche remodeling contribute to blood malignancies. Moreover, we discuss how these findings can be applied to non cell-autonomous therapies targeting the LSC niche. PMID:25748932

  4. Oxidative stress and hypoxia in normal and leukemic stem cells.

    PubMed

    Testa, Ugo; Labbaye, Catherine; Castelli, Germana; Pelosi, Elvira

    2016-07-01

    The main hematopoietic stem cell (HSC) functions, self-renewal and differentiation, are finely regulated by both intrinsic mechanisms such as transcriptional and epigenetic regulators and extrinsic signals originating in the bone marrow microenvironment (HSC niche) or in the body (humoral mediators). The interaction between regulatory signals and cellular metabolism is an emerging area. Several metabolic pathways function differently in HSCs compared with progenitors and differentiated cells. Hypoxia, acting through hypoxia-inducing factors, has emerged as a key regulator of stem cell biology and acts by maintaining HSC quiescence and a condition of metabolic dormancy based on anaerobic glycolytic energetic metabolism, with consequent low production reactive oxygen species (ROS) and high antioxidant defense. Hematopoietic cell differentiation is accompanied by changes in oxidative metabolism (decrease of anaerobic glycolysis and increase of oxidative phosphorylation) and increased levels of ROS. Leukemic stem cells, defined as the cells that initiate and maintain the leukemic process, show peculiar metabolic properties in that they are more dependent on oxidative respiration than on glycolysis and are more sensitive to oxidative stress than normal HSCs. Several mitochondrial abnormalities have been described in acute myeloid leukemia (AML) cells, explaining the shift to aerobic glycolysis observed in these cells and offering the unique opportunity for therapeutic metabolic targeting. Finally, frequent mutations of the mitochondrial isocitrate dehydrogenase-2 (IDH2) enzyme are observed in AML cells, in which the mutated enzyme acts as an oncogenic driver and can be targeted using specific inhibitors under clinical evaluation with promising results. PMID:27179622

  5. HMGA1 silencing restores normal stem cell characteristics in colon cancer stem cells by increasing p53 levels

    PubMed Central

    Puca, Francesca; Colamaio, Marianna; Federico, Antonella; Gemei, Marica; Tosti, Nadia; Bastos, André Uchimura; Vecchio, Luigi Del; Pece, Salvatore; Battista, Sabrina; Fusco, Alfredo

    2014-01-01

    High-mobility group A1 (HMGA1) proteins are architectural chromatinic proteins, abundantly expressed during embryogenesis and in most cancer tissues, but expressed at low levels or absent in normal adult tissues. Several studies have demonstrated that HMGA1 proteins play a causal role in neoplastic cell transformation. The aim of this study was to investigate the role of these proteins in the control of cancer stem cells (CSCs), which have emerged as a preferred target in cancer therapy, because of their role in cancer recurrence. We observed that HMGA1 is overexpressed in colon tumour stem cell (CTSC) lines compared to normal and colon cancer tissues. We demonstrated that HMGA1 silencing in CTSCs increases stem cell quiescence and reduces self-renewal and sphere-forming efficiency (SFE). The latter, together with the upregulation and asymmetric distribution of NUMB, is indicative of the recovery of an asymmetric division pattern, typical of normal stem cells. We further found that HMGA1 transcriptionally regulates p53, which is known to control the balance between symmetric and asymmetric divisions in CSCs. Therefore, our data indicate a critical role for HMGA1 in regulating both self-renewal and the symmetric/asymmetric division ratio in CSCs, suggesting that blocking HMGA1 function may be an effective anti-cancer therapy. PMID:24833610

  6. Mesenchymal Stem and Progenitor Cells in Normal and Dysplastic Hematopoiesis—Masters of Survival and Clonality?

    PubMed Central

    Pleyer, Lisa; Valent, Peter; Greil, Richard

    2016-01-01

    Myelodysplastic syndromes (MDS) are malignant hematopoietic stem cell disorders that have the capacity to progress to acute myeloid leukemia (AML). Accumulating evidence suggests that the altered bone marrow (BM) microenvironment in general, and in particular the components of the stem cell niche, including mesenchymal stem cells (MSCs) and their progeny, play a pivotal role in the evolution and propagation of MDS. We here present an overview of the role of MSCs in the pathogenesis of MDS, with emphasis on cellular interactions in the BM microenvironment and related stem cell niche concepts. MSCs have potent immunomodulatory capacities and communicate with diverse immune cells, but also interact with various other cellular components of the microenvironment as well as with normal and leukemic stem and progenitor cells. Moreover, compared to normal MSCs, MSCs in MDS and AML often exhibit altered gene expression profiles, an aberrant phenotype, and abnormal functional properties. These alterations supposedly contribute to the “reprogramming” of the stem cell niche into a disease-permissive microenvironment where an altered immune system, abnormal stem cell niche interactions, and an impaired growth control lead to disease progression. The current article also reviews molecular targets that play a role in such cellular interactions and possibilities to interfere with abnormal stem cell niche interactions by using specific targeted drugs. PMID:27355944

  7. Mesenchymal Stem and Progenitor Cells in Normal and Dysplastic Hematopoiesis-Masters of Survival and Clonality?

    PubMed

    Pleyer, Lisa; Valent, Peter; Greil, Richard

    2016-01-01

    Myelodysplastic syndromes (MDS) are malignant hematopoietic stem cell disorders that have the capacity to progress to acute myeloid leukemia (AML). Accumulating evidence suggests that the altered bone marrow (BM) microenvironment in general, and in particular the components of the stem cell niche, including mesenchymal stem cells (MSCs) and their progeny, play a pivotal role in the evolution and propagation of MDS. We here present an overview of the role of MSCs in the pathogenesis of MDS, with emphasis on cellular interactions in the BM microenvironment and related stem cell niche concepts. MSCs have potent immunomodulatory capacities and communicate with diverse immune cells, but also interact with various other cellular components of the microenvironment as well as with normal and leukemic stem and progenitor cells. Moreover, compared to normal MSCs, MSCs in MDS and AML often exhibit altered gene expression profiles, an aberrant phenotype, and abnormal functional properties. These alterations supposedly contribute to the "reprogramming" of the stem cell niche into a disease-permissive microenvironment where an altered immune system, abnormal stem cell niche interactions, and an impaired growth control lead to disease progression. The current article also reviews molecular targets that play a role in such cellular interactions and possibilities to interfere with abnormal stem cell niche interactions by using specific targeted drugs. PMID:27355944

  8. Normal and cancer stem cells of the human female reproductive system

    PubMed Central

    2013-01-01

    The female reproductive system (FRS) has a great capacity for regeneration. The existence of somatic stem cells (SSC) that are likely to reside in distinct tissue compartments of the FRS is anticipated. Normal SSC are capable of regenerating themselves, produce a progeny of cells that differentiate and maintain tissue architecture and functional characteristics, and respond to homeostatic controls. Among those SSC of the FRS that have been identified are: a) undifferentiated cells capable of differentiating into thecal cells and synthesizing hormones upon transplantation, b) ovarian surface epithelium stem cells, mitotically responsive to ovulation, c) uterine endometrial and myometrial cells, as clonogenic epithelial and stromal cells, and d) epithelial and mesenchymal cells with self-renewal capacity and multipotential from cervical tissues. Importantly, these cells are believed to significantly contribute to the development of different pathologies and tumors of the FRS. It is now widely accepted that cancer stem cells (CSC) are at the origin of many tumors. They are capable of regenerating themselves, produce a progeny that will differentiate aberrantly and do not respond adequately to homeostatic controls. Several cell surface antigens such as CD44, CD117, CD133 and MYD88 have been used to isolate ovarian cancer stem cells. Clonogenic epithelial and stromal endometrial and myometrial cells have been found in normal and cancer tissues, as side population, label-retaining cells, and CD146/PDGF-R beta-positive cells with stem-like features. In summary, here we describe a number of studies supporting the existence of somatic stem cells in the normal tissues and cancer stem cells in tumors of the human female reproductive system. PMID:23782518

  9. 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 ...

  10. Leptin and Adiponectin Modulate the Self-renewal of Normal Human Breast Epithelial Stem Cells.

    PubMed

    Esper, Raymond M; Dame, Michael; McClintock, Shannon; Holt, Peter R; Dannenberg, Andrew J; Wicha, Max S; Brenner, Dean E

    2015-12-01

    Multiple mechanisms are likely to account for the link between obesity and increased risk of postmenopausal breast cancer. Two adipokines, leptin and adiponectin, are of particular interest due to their opposing biologic functions and associations with breast cancer risk. In the current study, we investigated the effects of leptin and adiponectin on normal breast epithelial stem cells. Levels of leptin in human adipose explant-derived conditioned media positively correlated with the size of the normal breast stem cell pool. In contrast, an inverse relationship was found for adiponectin. Moreover, a strong linear relationship was observed between the leptin/adiponectin ratio in adipose conditioned media and breast stem cell self-renewal. Consistent with these findings, exogenous leptin stimulated whereas adiponectin suppressed breast stem cell self-renewal. In addition to local in-breast effects, circulating factors, including leptin and adiponectin, may contribute to the link between obesity and breast cancer. Increased levels of leptin and reduced amounts of adiponectin were found in serum from obese compared with age-matched lean postmenopausal women. Interestingly, serum from obese women increased stem cell self-renewal by 30% compared with only 7% for lean control serum. Taken together, these data suggest a plausible explanation for the obesity-driven increase in postmenopausal breast cancer risk. Leptin and adiponectin may function as both endocrine and paracrine/juxtacrine factors to modulate the size of the normal stem cell pool. Interventions that disrupt this axis and thereby normalize breast stem cell self-renewal could reduce the risk of breast cancer.

  11. Stem Cell Therapies for the Treatment of Radiation-Induced Normal Tissue Side Effects

    PubMed Central

    Benderitter, Marc; Caviggioli, Fabio; Chapel, Alain; Coppes, Robert P.; Guha, Chandan; Klinger, Marco; Malard, Olivier; Stewart, Fiona; Tamarat, Radia; Luijk, Peter Van

    2014-01-01

    Abstract Significance: Targeted irradiation is an effective cancer therapy but damage inflicted to normal tissues surrounding the tumor may cause severe complications. While certain pharmacologic strategies can temper the adverse effects of irradiation, stem cell therapies provide unique opportunities for restoring functionality to the irradiated tissue bed. Recent Advances: Preclinical studies presented in this review provide encouraging proof of concept regarding the therapeutic potential of stem cells for treating the adverse side effects associated with radiotherapy in different organs. Early-stage clinical data for radiation-induced lung, bone, and skin complications are promising and highlight the importance of selecting the appropriate stem cell type to stimulate tissue regeneration. Critical Issues: While therapeutic efficacy has been demonstrated in a variety of animal models and human trials, a range of additional concerns regarding stem cell transplantation for ameliorating radiation-induced normal tissue sequelae remain. Safety issues regarding teratoma formation, disease progression, and genomic stability along with technical issues impacting disease targeting, immunorejection, and clinical scale-up are factors bearing on the eventual translation of stem cell therapies into routine clinical practice. Future Directions: Follow-up studies will need to identify the best possible stem cell types for the treatment of early and late radiation-induced normal tissue injury. Additional work should seek to optimize cellular dosing regimes, identify the best routes of administration, elucidate optimal transplantation windows for introducing cells into more receptive host tissues, and improve immune tolerance for longer-term engrafted cell survival into the irradiated microenvironment. Antioxid. Redox Signal. 21: 338–355. PMID:24147585

  12. Mist1 Expressing Gastric Stem Cells Maintain the Normal and Neoplastic Gastric Epithelium and Are Supported by a Perivascular Stem Cell Niche.

    PubMed

    Hayakawa, Yoku; Ariyama, Hiroshi; Stancikova, Jitka; Sakitani, Kosuke; Asfaha, Samuel; Renz, Bernhard W; Dubeykovskaya, Zinaida A; Shibata, Wataru; Wang, Hongshan; Westphalen, Christoph B; Chen, Xiaowei; Takemoto, Yoshihiro; Kim, Woosook; Khurana, Shradha S; Tailor, Yagnesh; Nagar, Karan; Tomita, Hiroyuki; Hara, Akira; Sepulveda, Antonia R; Setlik, Wanda; Gershon, Michael D; Saha, Subhrajit; Ding, Lei; Shen, Zeli; Fox, James G; Friedman, Richard A; Konieczny, Stephen F; Worthley, Daniel L; Korinek, Vladimir; Wang, Timothy C

    2015-12-14

    The regulation and stem cell origin of normal and neoplastic gastric glands are uncertain. Here, we show that Mist1 expression marks quiescent stem cells in the gastric corpus isthmus. Mist1(+) stem cells serve as a cell-of-origin for intestinal-type cancer with the combination of Kras and Apc mutation and for diffuse-type cancer with the loss of E-cadherin. Diffuse-type cancer development is dependent on inflammation mediated by Cxcl12(+) endothelial cells and Cxcr4(+) gastric innate lymphoid cells (ILCs). These cells form the perivascular gastric stem cell niche, and Wnt5a produced from ILCs activates RhoA to inhibit anoikis in the E-cadherin-depleted cells. Targeting Cxcr4, ILCs, or Wnt5a inhibits diffuse-type gastric carcinogenesis, providing targets within the neoplastic gastric stem cell niche.

  13. Deep sequencing as a probe of normal stem cell fate and preneoplasia in human epidermis

    PubMed Central

    Simons, Benjamin D.

    2016-01-01

    Using deep sequencing technology, methods based on the sporadic acquisition of somatic DNA mutations in human tissues have been used to trace the clonal evolution of progenitor cells in diseased states. However, the potential of these approaches to explore cell fate behavior of normal tissues and the initiation of preneoplasia remain underexploited. Focusing on the results of a recent deep sequencing study of eyelid epidermis, we show that the quantitative analysis of mutant clone size provides a general method to resolve the pattern of normal stem cell fate and to detect and characterize the mutational signature of rare field transformations in human tissues, with implications for the early detection of preneoplasia. PMID:26699486

  14. Aging and insulin signaling differentially control normal and tumorous germline stem cells.

    PubMed

    Kao, Shih-Han; Tseng, Chen-Yuan; Wan, Chih-Ling; Su, Yu-Han; Hsieh, Chang-Che; Pi, Haiwei; Hsu, Hwei-Jan

    2015-02-01

    Aging influences stem cells, but the processes involved remain unclear. Insulin signaling, which controls cellular nutrient sensing and organismal aging, regulates the G2 phase of Drosophila female germ line stem cell (GSC) division cycle in response to diet; furthermore, this signaling pathway is attenuated with age. The role of insulin signaling in GSCs as organisms age, however, is also unclear. Here, we report that aging results in the accumulation of tumorous GSCs, accompanied by a decline in GSC number and proliferation rate. Intriguingly, GSC loss with age is hastened by either accelerating (through eliminating expression of Myt1, a cell cycle inhibitory regulator) or delaying (through mutation of insulin receptor (dinR) GSC division, implying that disrupted cell cycle progression and insulin signaling contribute to age-dependent GSC loss. As flies age, DNA damage accumulates in GSCs, and the S phase of the GSC cell cycle is prolonged. In addition, GSC tumors (which escape the normal stem cell regulatory microenvironment, known as the niche) still respond to aging in a similar manner to normal GSCs, suggesting that niche signals are not required for GSCs to sense or respond to aging. Finally, we show that GSCs from mated and unmated females behave similarly, indicating that female GSC-male communication does not affect GSCs with age. Our results indicate the differential effects of aging and diet mediated by insulin signaling on the stem cell division cycle, highlight the complexity of the regulation of stem cell aging, and describe a link between ovarian cancer and aging.

  15. Aging and insulin signaling differentially control normal and tumorous germline stem cells

    PubMed Central

    Kao, Shih-Han; Tseng, Chen-Yuan; Wan, Chih-Ling; Su, Yu-Han; Hsieh, Chang-Che; Pi, Haiwei; Hsu, Hwei-Jan

    2015-01-01

    Aging influences stem cells, but the processes involved remain unclear. Insulin signaling, which controls cellular nutrient sensing and organismal aging, regulates the G2 phase of Drosophila female germ line stem cell (GSC) division cycle in response to diet; furthermore, this signaling pathway is attenuated with age. The role of insulin signaling in GSCs as organisms age, however, is also unclear. Here, we report that aging results in the accumulation of tumorous GSCs, accompanied by a decline in GSC number and proliferation rate. Intriguingly, GSC loss with age is hastened by either accelerating (through eliminating expression of Myt1, a cell cycle inhibitory regulator) or delaying (through mutation of insulin receptor (dinR) GSC division, implying that disrupted cell cycle progression and insulin signaling contribute to age-dependent GSC loss. As flies age, DNA damage accumulates in GSCs, and the S phase of the GSC cell cycle is prolonged. In addition, GSC tumors (which escape the normal stem cell regulatory microenvironment, known as the niche) still respond to aging in a similar manner to normal GSCs, suggesting that niche signals are not required for GSCs to sense or respond to aging. Finally, we show that GSCs from mated and unmated females behave similarly, indicating that female GSC–male communication does not affect GSCs with age. Our results indicate the differential effects of aging and diet mediated by insulin signaling on the stem cell division cycle, highlight the complexity of the regulation of stem cell aging, and describe a link between ovarian cancer and aging. PMID:25470527

  16. Cellular differentiation hierarchies in normal and culture-adapted human embryonic stem cells.

    PubMed

    Enver, Tariq; Soneji, Shamit; Joshi, Chirag; Brown, John; Iborra, Francisco; Orntoft, Torben; Thykjaer, Thomas; Maltby, Edna; Smith, Kath; Abu Dawud, Raed; Jones, Mark; Matin, Maryam; Gokhale, Paul; Draper, Jonathan; Andrews, Peter W

    2005-11-01

    Human embryonic stem cell (HESC) lines vary in their characteristics and behaviour not only because they are derived from genetically outbred populations, but also because they may undergo progressive adaptation upon long-term culture in vitro. Such adaptation may reflect selection of variants with altered propensity for survival and retention of an undifferentiated phenotype. Elucidating the mechanisms involved will be important for understanding normal self-renewal and commitment to differentiation and for validating the safety of HESC-based therapy. We have investigated this process of adaptation at the cellular and molecular levels through a comparison of early passage (normal) and late passage (adapted) sublines of a single HESC line, H7. To account for spontaneous differentiation that occurs in HESC cultures, we sorted cells for SSEA3, which marks undifferentiated HESC. We show that the gene expression programmes of the adapted cells partially reflected their aberrant karyotype, but also resulted from a failure in X-inactivation, emphasizing the importance in adaptation of karyotypically silent epigenetic changes. On the basis of growth potential, ability to re-initiate ES cultures and global transcription profiles, we propose a cellular differentiation hierarchy for maintenance cultures of HESC: normal SSEA3+ cells represent pluripotent stem cells. Normal SSEA3- cells have exited this compartment, but retain multilineage differentiation potential. However, adapted SSEA3+ and SSEA3- cells co-segregate within the stem cell territory, implying that adaptation reflects an alteration in the balance between self-renewal and differentiation. As this balance is also an essential feature of cancer, the mechanisms of culture adaptation may mirror those of oncogenesis and tumour progression. PMID:16159889

  17. Identification of stem cell transcriptional programs normally expressed in embryonic and neural stem cells in alloreactive CD8+ T cells mediating graft-versus-host disease

    PubMed Central

    Kato, Koji; Cui, Shuaiying; Kuick, Rork; Mineishi, Shin; Hexner, Elizabeth; Ferrara, James LM; Emerson, Stephen G.; Zhang, Yi

    2010-01-01

    A hallmark of graft-versus-host-disease (GVHD), a life-threatening complication after allogeneic hematopoietic stem cell transplantation, is the cytopathic injury of host tissues mediated by persistent alloreactive effector T cells (TE). However, the mechanisms that regulate the persistence of alloreactive TE during GVHD remain largely unknown. Using mouse GVHD models, we demonstrate that alloreactive CD8+ TE rapidly diminished in vivo when adoptively transferred into irradiated secondary congenic recipient mice. In contrast, although alloreactive CD8+ TE underwent massive apoptosis upon chronic exposure to alloantigens, they proliferated in vivo in secondary allogeneic recipients, persisted and caused severe GVHD. Thus, the continuous proliferation of alloreactive CD8+ TE, which is mediated by alloantigenic stimuli rather than homeostatic factors, is critical to maintaining their persistence. Gene expression profile analysis revealed that while alloreactive CD8+ TE increased the expression of genes associated with cell death, they activated a group of stem cell genes normally expressed in embryonic and neural stem cells. Most of these stem cell genes are associated with cell cycle regulation, DNA replication, chromatin modification and transcription. One of these genes, Ezh2, which encodes a chromatin modifying enzyme, was abundantly expressed in CD8+ TE. Silencing Ezh2 significantly reduced the proliferation of alloantigen-activated CD8+ T cells. Thus, these findings identify that a group of stem cell genes could play important roles in sustaining terminally differentiated alloreactive CD8+ TE and may be therapeutic targets for controlling GVHD. PMID:20116439

  18. Identification of normal and neoplastic stem cells by the multicolor lineage tracing methods.

    PubMed

    Ueno, Hiroo

    2016-08-01

    Adult stem cells and embryonic (ES) and induced pluripotent stem (iPS) cells are two major focus areas of stem cell research. Studies on adult stem cells are important not only as sources for regenerative medicine but for analyzing the mechanisms of tissue homeostasis, tissue repair after injury, cancinogenesis, and aging. On the other hand, ES and iPS cells are mainly important for regenerative medicine. However, many adult stem cells, especially those in low-turnover tissues, have remained unidentified. We have been working on the development of methods using multiple fluorescent markers, to improve the accuracy of lineage-tracing analyses of adult stem cells and their fetal progenitors. With this method, we were able to identify lingual epithelial stem cells (LESCs). By using the same strategy, we could potentially identify candidate cancer stem cells. In this review, we would like to introduce how the multicolor lineage tracing method could be used in various stem cell studies.

  19. Normal and neoplastic urothelial stem cells: getting to the root of the problem

    PubMed Central

    Ho, Philip Levy; Kurtova, Antonina; Chan, Keith Syson

    2012-01-01

    Most epithelial tissues contain self-renewing stem cells that mature into downstream progenies with increasingly limited differentiation potential. It is not surprising that cancers arising from such hierarchically organized epithelial tissues retain features of cellular differentiation. Accumulating evidence suggests that the urothelium of the urinary bladder is a hierarchically organized tissue, containing tissue-specific stem cells that are important for both normal homeostasis and injury response. The phenotypic and functional properties of cancer stem cells (CSCs; also known as tumour-initiating cells) from bladder cancer tissue have been studied in detail. Urothelial CSCs are not isolated by a ‘one-marker-fits-all’ approach; instead, various cell surface marker combinations (possibly reflecting the cell-of-origin) are used to isolate CSCs from distinct differentiation subtypes of urothelial carcinomas. Additional CSC markers, including cytokeratin 14 (CK14), aldehyde dehydrogenase 1 family, member A1 (ALDH1A1), and tumour protein 63 (p63), have revealed prognostic value for urothelial carcinomas. Signalling pathways involved in normal stem cell self-renewal and differentiation are implicated in the malignant transformation of different subsets of urothelial carcinomas. Early expansion of primitive CK14+ cells—driven by genetic pathways such as STAT3—can lead to the development of carcinoma in situ, and CSC-enriched urothelial carcinomas are associated with poor clinical outcomes. Given that bladder CSCs are the proposed root of malignancy and drivers of cancer initiation and progression for urothelial carcinomas, these cells are ideal targets for anticancer therapies. PMID:22890301

  20. Comparative evaluation of cancer stem cell markers in normal pancreas and pancreatic ductal adenocarcinoma.

    PubMed

    Vizio, Barbara; Mauri, Francesco A; Prati, Adriana; Trivedi, Pritesh; Giacobino, Alice; Novarino, Anna; Satolli, Maria Antonietta; Ciuffreda, Libero; Camandona, Michele; Gasparri, Guido; Bellone, Graziella

    2012-01-01

    Chemoresistance and self-renewal of cancer stem cells (CSC), found in many tumors including pancreatic ductal adenocarcinoma (PDAC), are believed to underlie tumor mass regrowth. The distribution of cells carrying the putative stem-cell markers CD133, Nestin, Notch1-4, Jagged1 and 2, ABCG2 and aldehyde dehydrogenase (ALDH1) was assessed immunohistochemically using PDAC and normal pancreas tissue microarrays. The immunoreactivity was semi-quantitatively graded against the normal pancreas and was correlated with the differentiation grade and disease stage. No statistical significant differences were found between normal pancreas and PDAC in the expression of Nestin, Notch1, 3 and 4, ABCG2 or ALDH1. Notch2 and Jagged1 and 2 expression were increased in PDAC. CD133-positive cells were above-normal in PDAC, but the difference was not statistically significant. Nestin, Notch1-4, Jagged1, ABCG2 and ALDH1 immunostaining scores were not correlated with tumor grade or disease stage. CD133 and Notch2 expression was significantly inversely correlated with tumor grade, but not disease stage. Notch3 immunostaining positively correlated with tumor stage, but not with differentiation grade. Jagged2 protein expression correlated inversely with disease stage, but not with tumor grade. From the clinical standpoint, improved delineation of the tumor CSC signature, putatively responsible for tumor initiation and recurrence after initial response to chemotherapy, may offer novel therapeutic targets for this highly lethal cancer.

  1. Unique epigenetic influence of H2AX phosphorylation and H3K56 acetylation on normal stem cell radioresponses

    PubMed Central

    Jacobs, Keith M.; Misri, Sandeep; Meyer, Barbara; Raj, Suyash; Zobel, Cheri L.; Sleckman, Barry P.; Hallahan, Dennis E.; Sharma, Girdhar G.

    2016-01-01

    Normal tissue injury resulting from cancer radiotherapy is often associated with diminished regenerative capacity. We examined the relative radiosensitivity of normal stem cell populations compared with non–stem cells within several radiosensitive tissue niches and culture models. We found that these stem cells are highly radiosensitive, in contrast to their isogenic differentiated progeny. Of interest, they also exhibited a uniquely attenuated DNA damage response (DDR) and muted DNA repair. Whereas stem cells exhibit reduced ATM activation and ionizing radiation–induced foci, they display apoptotic pannuclear H2AX-S139 phosphorylation (γH2AX), indicating unique radioresponses. We also observed persistent phosphorylation of H2AX-Y142 along the DNA breaks in stem cells, which promotes apoptosis while inhibiting DDR signaling. In addition, down-regulation of constitutively elevated histone-3 lysine-56 acetylation (H3K56ac) in stem cells significantly decreased their radiosensitivity, restored DDR function, and increased survival, signifying its role as a key contributor to stem cell radiosensitivity. These results establish that unique epigenetic landscapes affect cellular heterogeneity in radiosensitivity and demonstrate the nonubiquitous nature of radiation responses. We thus elucidate novel epigenetic rheostats that promote ionizing radiation hypersensitivity in various normal stem cell populations, identifying potential molecular targets for pharmacological radioprotection of stem cells and hopefully improving the efficacy of future cancer treatment. PMID:26941327

  2. Prolyl-isomerase Pin1 controls normal and cancer stem cells of the breast

    PubMed Central

    Rustighi, Alessandra; Zannini, Alessandro; Tiberi, Luca; Sommaggio, Roberta; Piazza, Silvano; Sorrentino, Giovanni; Nuzzo, Simona; Tuscano, Antonella; Eterno, Vincenzo; Benvenuti, Federica; Santarpia, Libero; Aifantis, Iannis; Rosato, Antonio; Bicciato, Silvio; Zambelli, Alberto; Del Sal, Giannino

    2014-01-01

    Mammary epithelial stem cells are fundamental to maintain tissue integrity. Cancer stem cells (CSCs) are implicated in both treatment resistance and disease relapse, and the molecular bases of their malignant properties are still poorly understood. Here we show that both normal stem cells and CSCs of the breast are controlled by the prolyl-isomerase Pin1. Mechanistically, following interaction with Pin1, Notch1 and Notch4, key regulators of cell fate, escape from proteasomal degradation by their major ubiquitin-ligase Fbxw7α. Functionally, we show that Fbxw7α acts as an essential negative regulator of breast CSCs' expansion by restraining Notch activity, but the establishment of a Notch/Pin1 active circuitry opposes this effect, thus promoting breast CSCs self-renewal, tumor growth and metastasis in vivo. In human breast cancers, despite Fbxw7α expression, high levels of Pin1 sustain Notch signaling, which correlates with poor prognosis. Suppression of Pin1 holds promise in reverting aggressive phenotypes, through CSC exhaustion as well as recovered drug sensitivity carrying relevant implications for therapy of breast cancers. PMID:24357640

  3. Fourier transform infrared (FTIR) spectromicroscopic characterization of stem-like cell populations in human esophageal normal and adenocarcinoma cell lines.

    PubMed

    Zhao, R; Quaroni, L; Casson, A G

    2010-01-01

    We have tested an approach to identify putative cancer stem cells that involves measurement of the infrared absorption spectrum of individual cells in an aqueous environment, and their subsequent classification using multivariate data analysis techniques. Two primary esophageal cell lines were characterized: the immortalized normal esophageal epithelial cell line, Het-1A, and the esophageal adenocarcinoma cell line, OE33. In addition, we also evaluated spheroids, reflecting stem-like cell populations, which were derived from each parent cell line when grown in serum-free media. As differences in cell size appeared to be a strong discriminating factor, a correction needs to be performed to allow a reliable classification based on infrared absorption spectra. We demonstrated that stem-like cells derived from Het-1A could easily be discriminated on the basis of absorbance differences in the 1000-1200 cm(-1) spectral interval, whereas this was not possible for OE33. Furthermore, we found that changes due to aging of OE33 cells in culture dominated the infrared absorption spectra and somewhat limited the potential of this approach to identify stem-like cell populations using this in vitro model system.

  4. Human pluripotent stem cells as a model of trophoblast differentiation in both normal development and disease.

    PubMed

    Horii, Mariko; Li, Yingchun; Wakeland, Anna K; Pizzo, Donald P; Nelson, Katharine K; Sabatini, Karen; Laurent, Louise Chang; Liu, Ying; Parast, Mana M

    2016-07-01

    Trophoblast is the primary epithelial cell type in the placenta, a transient organ required for proper fetal growth and development. Different trophoblast subtypes are responsible for gas/nutrient exchange (syncytiotrophoblasts, STBs) and invasion and maternal vascular remodeling (extravillous trophoblasts, EVTs). Studies of early human placental development are severely hampered by the lack of a representative trophoblast stem cell (TSC) model with the capacity for self-renewal and the ability to differentiate into both STBs and EVTs. Primary cytotrophoblasts (CTBs) isolated from early-gestation (6-8 wk) human placentas are bipotential, a phenotype that is lost with increasing gestational age. We have identified a CDX2(+)/p63(+) CTB subpopulation in the early postimplantation human placenta that is significantly reduced later in gestation. We describe a reproducible protocol, using defined medium containing bone morphogenetic protein 4 by which human pluripotent stem cells (hPSCs) can be differentiated into CDX2(+)/p63(+) CTB stem-like cells. These cells can be replated and further differentiated into STB- and EVT-like cells, based on marker expression, hormone secretion, and invasive ability. As in primary CTBs, differentiation of hPSC-derived CTBs in low oxygen leads to reduced human chorionic gonadotropin secretion and STB-associated gene expression, instead promoting differentiation into HLA-G(+) EVTs in an hypoxia-inducible, factor-dependent manner. To validate further the utility of hPSC-derived CTBs, we demonstrated that differentiation of trisomy 21 (T21) hPSCs recapitulates the delayed CTB maturation and blunted STB differentiation seen in T21 placentae. Collectively, our data suggest that hPSCs are a valuable model of human placental development, enabling us to recapitulate processes that result in both normal and diseased pregnancies. PMID:27325764

  5. Aldehyde dehydrogenases inhibition eradicates leukemia stem cells while sparing normal progenitors

    PubMed Central

    Venton, G; Pérez-Alea, M; Baier, C; Fournet, G; Quash, G; Labiad, Y; Martin, G; Sanderson, F; Poullin, P; Suchon, P; Farnault, L; Nguyen, C; Brunet, C; Ceylan, I; Costello, R T

    2016-01-01

    The vast majority of patients with acute myeloid leukemia (AML) achieve complete remission (CR) after standard induction chemotherapy. However, the majority subsequently relapse and die of the disease. A leukemia stem cell (LSC) paradigm has been invoked to explain this failure of CR to reliably translate into cure. Indeed, LSCs are highly enriched in CD34+CD38− leukemic cells that exhibit positive aldehyde dehydrogenase activity (ALDH+) on flow cytometry, these LSCs are resistant to currently existing treatments in AML such as cytarabine and anthracycline that, at the cost of great toxicity on normal cells, are highly active against the leukemic bulk, but spare the LSCs responsible for relapse. To try to combat the LSC population selectively, a well-characterized ALDH inhibitor by the trivial name of dimethyl ampal thiolester (DIMATE) was assessed on sorted CD34+CD38− subpopulations from AML patients and healthy patients. ALDH activity and cell viability were monitored by flow cytometry. From enzyme kinetic studies DIMATE is an active enzyme-dependent, competitive, irreversible inhibitor of ALDH1. On cells in culture, DIMATE is a powerful inhibitor of ALDHs 1 and 3, has a major cytotoxic activity on human AML cell lines. Moreover, DIMATE is highly active against leukemic populations enriched in LSCs, but, unlike conventional chemotherapy, DIMATE is not toxic for healthy hematopoietic stem cells which retained, after treatment, their self-renewing and multi-lineage differentiation capacity in immunodeficient mice, xenografted with human leukemic cells. DIMATE eradicates specifically human AML cells and spares healthy mouse hematologic cells. PMID:27611922

  6. Aldehyde dehydrogenases inhibition eradicates leukemia stem cells while sparing normal progenitors.

    PubMed

    Venton, G; Pérez-Alea, M; Baier, C; Fournet, G; Quash, G; Labiad, Y; Martin, G; Sanderson, F; Poullin, P; Suchon, P; Farnault, L; Nguyen, C; Brunet, C; Ceylan, I; Costello, R T

    2016-01-01

    The vast majority of patients with acute myeloid leukemia (AML) achieve complete remission (CR) after standard induction chemotherapy. However, the majority subsequently relapse and die of the disease. A leukemia stem cell (LSC) paradigm has been invoked to explain this failure of CR to reliably translate into cure. Indeed, LSCs are highly enriched in CD34+CD38- leukemic cells that exhibit positive aldehyde dehydrogenase activity (ALDH+) on flow cytometry, these LSCs are resistant to currently existing treatments in AML such as cytarabine and anthracycline that, at the cost of great toxicity on normal cells, are highly active against the leukemic bulk, but spare the LSCs responsible for relapse. To try to combat the LSC population selectively, a well-characterized ALDH inhibitor by the trivial name of dimethyl ampal thiolester (DIMATE) was assessed on sorted CD34+CD38- subpopulations from AML patients and healthy patients. ALDH activity and cell viability were monitored by flow cytometry. From enzyme kinetic studies DIMATE is an active enzyme-dependent, competitive, irreversible inhibitor of ALDH1. On cells in culture, DIMATE is a powerful inhibitor of ALDHs 1 and 3, has a major cytotoxic activity on human AML cell lines. Moreover, DIMATE is highly active against leukemic populations enriched in LSCs, but, unlike conventional chemotherapy, DIMATE is not toxic for healthy hematopoietic stem cells which retained, after treatment, their self-renewing and multi-lineage differentiation capacity in immunodeficient mice, xenografted with human leukemic cells. DIMATE eradicates specifically human AML cells and spares healthy mouse hematologic cells. PMID:27611922

  7. The role of the basal stem cell of the human breast in normal development and cancer

    PubMed Central

    Russo, Jose; Russo, Irma H.

    2011-01-01

    MCF-10F a spontaneously immortalized ERα negative human breast epithelial cell line derived from breast tissues containing Lobules type 1, is able to form normal ductal structures in a tridimensional collagen matrix system. MCF-10F cells that are Estrogen-transformed [trMCF cells] progressively express phenotypes of in vitro cell transformation, including colony formation in agar methocel, and loss of the ductulogenic capacity. Further selection of these trMCF cells for invasiveness in a Matrigel invasion system identified cells [bcMCF] that formed tumors in severe combined immunodeficient [SCID] mice. The cell lines derived from those tumors [caMCF] were poorly differentiated ERα, PR and ERBB2 negative adenocarcinomas. These characteristics are similar to the human basal cell-like carcinomas. This in vitro in vivo model demonstrates the importance of the basal cell type as a stem cell that reconstitute the branching pattern of the breast and that is also target of a carcinogenic insult leading to transformation and cancer. PMID:21901623

  8. Characterization of mesenchymal stem cells from human normal and hyperplastic gingiva.

    PubMed

    Tang, Liang; Li, Nan; Xie, Han; Jin, Yan

    2011-03-01

    Human gingiva plays an important role in the maintenance of oral health and shows unique fetal-like scarless healing process after wounding. Here we isolate and characterize mesenchymal stem cells from human normal and hyperplastic gingival tissues (N-GMSC and H-GMSC, respectively). Immunocytochemical staining indicated that gingival lamina propria contained Stro-1 and SSEA-4 positive cells, implying existence of putative gingival MSC. Under attachment-based isolating and culturing condition, gingival MSC displayed highly clonogenic and long-term proliferative capability. By using single colony isolation and expansion approaches, we found both N-GMSC and H-GMSC possessed self-renewal and multipotent differentiation properties. N-GMSC and H-GMSC showed distinct immunoregulatory functions in a murine skin allograft setting via up-regulation of putative systemic regulatory T cells (Tregs). N-GMSC and H-GMSC were capable of regenerating collagenous tissue following in vivo transplantation, in which H-GMSC exhibited more robust regenerative capability. These findings suggest that gingival tissue contains tissue-specific mesenchymal stem cell population and is an ideal resource for immunoregulatory therapy due to its substantial availability and accessibility. In addition, gingival MSC over-activation may contribute to gingival hyperplastic phenotype.

  9. Evolution of normal and neoplastic tissue stem cells: progress after Robert Hooke.

    PubMed

    Weissman, Irving

    2015-10-19

    The appearance of stem cells coincides with the transition from single-celled organisms to metazoans. Stem cells are capable of self-renewal as well as differentiation. Each tissue is maintained by self-renewing tissue-specific stem cells. The accumulation of mutations that lead to preleukaemia are in the blood-forming stem cell, while the transition to leukaemia stem cells occurs in the clone at a progenitor stage. All leukaemia and cancer cells escape being removed by scavenger macrophages by expressing the 'don't eat me' signal CD47. Blocking antibodies to CD47 are therapeutics for all cancers, and are currently being tested in clinical trials in the US and UK. PMID:26416675

  10. Evolution of normal and neoplastic tissue stem cells: progress after Robert Hooke.

    PubMed

    Weissman, Irving

    2015-10-19

    The appearance of stem cells coincides with the transition from single-celled organisms to metazoans. Stem cells are capable of self-renewal as well as differentiation. Each tissue is maintained by self-renewing tissue-specific stem cells. The accumulation of mutations that lead to preleukaemia are in the blood-forming stem cell, while the transition to leukaemia stem cells occurs in the clone at a progenitor stage. All leukaemia and cancer cells escape being removed by scavenger macrophages by expressing the 'don't eat me' signal CD47. Blocking antibodies to CD47 are therapeutics for all cancers, and are currently being tested in clinical trials in the US and UK.

  11. Evolution of normal and neoplastic tissue stem cells: progress after Robert Hooke

    PubMed Central

    Weissman, Irving

    2015-01-01

    The appearance of stem cells coincides with the transition from single-celled organisms to metazoans. Stem cells are capable of self-renewal as well as differentiation. Each tissue is maintained by self-renewing tissue-specific stem cells. The accumulation of mutations that lead to preleukaemia are in the blood-forming stem cell, while the transition to leukaemia stem cells occurs in the clone at a progenitor stage. All leukaemia and cancer cells escape being removed by scavenger macrophages by expressing the 'don't eat me' signal CD47. Blocking antibodies to CD47 are therapeutics for all cancers, and are currently being tested in clinical trials in the US and UK. PMID:26416675

  12. Breast Cancer Stem Cells Transition between Epithelial and Mesenchymal States Reflective of their Normal Counterparts

    PubMed Central

    Liu, Suling; Cong, Yang; Wang, Dong; Sun, Yu; Deng, Lu; Liu, Yajing; Martin-Trevino, Rachel; Shang, Li; McDermott, Sean P.; Landis, Melissa D.; Hong, Suhyung; Adams, April; D’Angelo, Rosemarie; Ginestier, Christophe; Charafe-Jauffret, Emmanuelle; Clouthier, Shawn G.; Birnbaum, Daniel; Wong, Stephen T.; Zhan, Ming; Chang, Jenny C.; Wicha, Max S.

    2013-01-01

    Summary Previous studies have suggested that breast cancer stem cells (BCSCs) mediate metastasis, are resistant to radiation and chemotherapy, and contribute to relapse. Although several BCSC markers have been described, it is unclear whether these markers identify the same or independent BCSCs. Here, we show that BCSCs exist in distinct mesenchymal-like (epithelial-mesenchymal transition [EMT]) and epithelial-like (mesenchymal-epithelial transition [MET]) states. Mesenchymal-like BCSCs characterized as CD24−CD44+ are primarily quiescent and localized at the tumor invasive front, whereas epithelial-like BCSCs express aldehyde dehydrogenase (ALDH), are proliferative, and are located more centrally. The gene-expression profiles of mesenchymal-like and epithelial-like BCSCs are remarkably similar across different molecular subtypes of breast cancer, and resemble those of distinct basal and luminal stem cells found in the normal breast. We propose that the plasticity of BCSCs that allows them to transition between EMT- and MET-like states endows these cells with the capacity for tissue invasion, dissemination, and growth at metastatic sites. PMID:24511467

  13. A differential role for CXCR4 in the regulation of normal versus malignant breast stem cell activity.

    PubMed

    Ablett, Matthew P; O'Brien, Ciara S; Sims, Andrew H; Farnie, Gillian; Clarke, Robert B

    2014-02-15

    C-X-C chemokine receptor type 4 (CXCR4) is known to regulate lung, pancreatic and prostate cancer stem cells. In breast cancer, CXCR4 signalling has been reported to be a mediator of metastasis, and is linked to poor prognosis. However its role in normal and malignant breast stem cell function has not been investigated. Anoikis resistant (AR) cells were collected from immortalised (MCF10A, 226L) and malignant (MCF7, T47D, SKBR3) breast cell lines and assessed for stem cell enrichment versus unsorted cells. AR cells had significantly higher mammosphere forming efficiency (MFE) than unsorted cells. The AR normal cells demonstrated increased formation of 3D structures in Matrigel compared to unsorted cells. In vivo, SKBR3 and T47D AR cells had 7- and 130-fold enrichments for tumour formationrespectively, compared with unsorted cells. AR cells contained significantly elevated CXCR4 transcript and protein levels compared to unsorted cells. Importantly, CXCR4 mRNA was higher in stem cell-enriched CD44+/CD24- patient-derived breast cancer cells compared to non-enriched cells. CXCR4 stimulation by its ligand SDF-1 reduced MFE of the normal breast cells lines but increased the MFE in T47D and patient-derived breast cancer cells. CXCR4 inhibition by AMD3100 increased stem cell activity but reduced the self-renewal capacity of the malignant breast cell line T47D. CXCR4+ FACS sorted MCF7 cells demonstrated a significantly increased MFE compared with CXCR4- cells. This significant increase in MFE was further demonstrated in CXCR4 over-expressing MCF7 cells which also had an increase in self-renewal compared to parental cells. A greater reduction in self-renewal following CXCR4 inhibition in the CXCR4 over-expressing cells compared with parental cells was also observed. Our data establish for the first time that CXCR4 signalling has contrasting effects on normal and malignant breast stem cell activity. Here, we demonstrate that CXCR4 signalling specifically regulates breast

  14. A differential role for CXCR4 in the regulation of normal versus malignant breast stem cell activity

    PubMed Central

    Ablett, Matthew P.; O'Brien, Ciara S.; Sims, Andrew H.; Farnie, Gillian; Clarke, Robert B.

    2014-01-01

    C-X-C chemokine receptor type 4 (CXCR4) is known to regulate lung, pancreatic and prostate cancer stem cells. In breast cancer, CXCR4 signalling has been reported to be a mediator of metastasis, and is linked to poor prognosis. However its role in normal and malignant breast stem cell function has not been investigated. Anoikis resistant (AR) cells were collected from immortalised (MCF10A, 226L) and malignant (MCF7, T47D, SKBR3) breast cell lines and assessed for stem cell enrichment versus unsorted cells. AR cells had significantly higher mammosphere forming efficiency (MFE) than unsorted cells. The AR normal cells demonstrated increased formation of 3D structures in Matrigel compared to unsorted cells. In vivo, SKBR3 and T47D AR cells had 7- and 130-fold enrichments for tumour formation respectively, compared with unsorted cells. AR cells contained significantly elevated CXCR4 transcript and protein levels compared to unsorted cells. Importantly, CXCR4 mRNA was higher in stem cell-enriched CD44+ /CD24− - patient-derived breast cancer cells compared to non-enriched cells. CXCR4 stimulation by its ligand SDF-1 reduced MFE of the normal breast cells lines but increased the MFE in T47D and patient-derived breast cancer cells. CXCR4 inhibition by AMD3100 increased stem cell activity but reduced the self-renewal capacity of the malignant breast cell line T47D. CXCR4 + FACS sorted MCF7 cells demonstrated a significantly increased MFE compared with CXCR4- cells. This significant increase in MFE was further demonstrated in CXCR4 over-expressing MCF7 cells which also had an increase in self-renewal compared to parental cells. A greater reduction in self-renewal following CXCR4 inhibition in the CXCR4 over-expressing cells compared with parental cells was also observed. Our data establish for the first time that CXCR4 signalling has contrasting effects on normal and malignant breast stem cell activity. Here, we demonstrate that CXCR4 signalling specifically regulates

  15. Hematopoietic Stem Cells Transplantation Can Normalize Thyroid Function in a Cystinosis Mouse Model.

    PubMed

    Gaide Chevronnay, H P; Janssens, V; Van Der Smissen, P; Rocca, C J; Liao, X H; Refetoff, S; Pierreux, C E; Cherqui, S; Courtoy, P J

    2016-04-01

    Hypothyroidism is the most frequent and earliest endocrine complication in cystinosis, a multisystemic lysosomal storage disease caused by defective transmembrane cystine transporter, cystinosin (CTNS gene). We recently demonstrated in Ctns(-/-) mice that altered thyroglobulin biosynthesis associated with endoplasmic reticulum stress, combined with defective lysosomal processing, caused hypothyroidism. In Ctns(-/-) kidney, hematopoietic stem cell (HSC) transplantation provides long-term functional and structural protection. Tissue repair involves transfer of cystinosin-bearing lysosomes from HSCs differentiated as F4/80 macrophages into deficient kidney tubular cells, via tunneling nanotubes that cross basement laminae. Here we evaluated the benefit of HSC transplantation for cystinotic thyroid and investigated the underlying mechanisms. HSC engraftment in Ctns(-/-) thyroid drastically decreased cystine accumulation, normalized the TSH level, and corrected the structure of a large fraction of thyrocytes. In the thyroid microenvironment, HSCs differentiated into a distinct, mixed macrophage/dendritic cell lineage expressing CD45 and major histocompatibility complex II but low CD11b and F4/80. Grafted HSCs closely apposed to follicles and produced tunneling nanotube-like extensions that crossed follicular basement laminae. HSCs themselves further squeezed into follicles, allowing extensive contact with thyrocytes, but did not transdifferentiate into Nkx2.1-expressing cells. Our observations revealed significant differences of basement lamina porosity between the thyroid and kidney and/or intrinsic macrophage invasive properties once in the thyroid microenvironment. The contrast between extensive thyrocyte protection and low HSC abundance at steady state suggests multiple sequential encounters and/or remanent impact. This is the first report demonstrating the potential of HSC transplantation to correct thyroid disease and supports a major multisystemic benefit of stem

  16. Role of microRNA221 in regulating normal mammary epithelial hierarchy and breast cancer stem-like cells

    PubMed Central

    Hong, Su-Hyung; Bai, Shoumin; He, Zhen; Malik, Fayaz; Xu, Jiahui; Zhou, Lei; Chen, Weilong; Martin-Trevino, Rachel; Wu, Xiaojian; Lan, Ping; Yi, Yongju; Ginestier, Christophe; Ibarra, Ingrid; Shang, Li; McDermott, Sean; Luther, Tahra; Clouthier, Shawn G.; Wicha, Max S.; Liu, Suling

    2015-01-01

    Increasing evidence suggests that lineage specific subpopulations and stem-like cells exist in normal and malignant breast tissues. Epigenetic mechanisms maintaining this hierarchical homeostasis remain to be investigated. In this study, we found the level of microRNA221 (miR-221) was higher in stem-like and myoepithelial cells than in luminal cells isolated from normal and malignant breast tissue. In normal breast cells, over-expression of miR-221 generated more myoepithelial cells whereas knock-down of miR-221 increased luminal cells. Over-expression of miR-221 stimulated stem-like cells in luminal type of cancer and the miR-221 level was correlated with clinical outcome in breast cancer patients. Epithelial-mesenchymal transition (EMT) was induced by overexpression of miR-221 in normal and breast cancer cells. The EMT related gene ATXN1 was found to be a miR-221 target gene regulating breast cell hierarchy. In conclusion, we propose that miR-221 contributes to lineage homeostasis of normal and malignant breast epithelium. PMID:25686829

  17. Types of Stem Cells

    MedlinePlus

    ... PDF) Download an introduction to stem cells and stem cell research. Stem Cell Glossary Stem cell terms to know. ... stem cells blog from the International Society for Stem Cell Research. Learn About Stem Cells From Lab to You ...

  18. DIET CONTROLS NORMAL AND TUMOROUS GERMLINE STEM CELLS VIA INSULIN-DEPENDENT AND -INDEPENDENT MECHANISMS IN DROSOPHILA

    PubMed Central

    Hsu, Hwei-Jan; LaFever, Leesa; Drummond-Barbosa, Daniela

    2008-01-01

    The external environment influences stem cells, but this process is poorly understood. Our previous work showed that germline stem cells (GSCs) respond to diet via neural insulin-like peptides (DILPs) that act directly on the germ line to upregulate stem cell division and cyst growth under a protein-rich diet in Drosophila. Here, we report that DILPs specifically control the G2 phase of the GSC cell cycle via phosphoinositide-3 kinase (PI3K) and dFOXO, and that a separate diet mediator regulates the G1 phase. Furthermore, GSC tumors, which escape the normal stem cell regulatory microenvironment, or niche, still respond to diet via both mechanisms, indicating that niche signals are not required for GSCs to sense or respond to diet. Our results document the effect of diet and insulin-like signals on the cell cycle of stem cells within an intact organism, and demonstrate that the response to diet requires multiple signals. Moreover, the retained ability of GSC tumors to respond to diet parallels the long known connections between diet, insulin signaling, and cancer risk in humans. PMID:18068153

  19. Stem cells supporting other stem cells

    PubMed Central

    Leatherman, Judith

    2013-01-01

    Adult stem cell therapies are increasingly prevalent for the treatment of damaged or diseased tissues, but most of the improvements observed to date are attributed to the ability of stem cells to produce paracrine factors that have a trophic effect on existing tissue cells, improving their functional capacity. It is now clear that this ability to produce trophic factors is a normal and necessary function for some stem cell populations. In vivo adult stem cells are thought to self-renew due to local signals from the microenvironment where they live, the niche. Several niches have now been identified which harbor multiple stem cell populations. In three of these niches – the Drosophila testis, the bulge of the mammalian hair follicle, and the mammalian bone marrow – one type of stem cell has been found to produce factors that contribute to the maintenance of a second stem cell population in the shared niche. In this review, I will examine the architecture of these three niches and discuss the molecular signals involved. Together, these examples establish a new paradigm for stem cell behavior, that stem cells can promote the maintenance of other stem cells. PMID:24348512

  20. JNK pathway inhibition selectively primes pancreatic cancer stem cells to TRAIL-induced apoptosis without affecting the physiology of normal tissue resident stem cells

    PubMed Central

    Rhea, P. Robyn; Kettlun, Claudia; Heinemann, Mitja L.; Ruetering, Jennifer; Vykoukal, Jody; Alt, Eckhard

    2016-01-01

    Objective Successful treatment of solid cancers mandates targeting cancer stem cells (CSC) without impact on the physiology of normal tissue resident stem cells. C-Jun N-terminal kinase (JNK) signaling has been shown to be of importance in cancer. We test whether JNK inhibition would sensitize pancreatic CSCs to induction of apoptosis via low-dose TNFα-related apoptosis-inducing ligand (TRAIL). Design Effects of JNK inhibition (JNKi) were evaluated in vitro in functional assays, through mRNA and protein expression analysis, and in in vivo mouse studies. CSCs were enriched in anoikis-resistant spheroid culture and analyzed accordingly. Results We confirmed that the JNK pathway is an important regulatory pathway in pancreatic cancer stem cells and further found that JNK inhibition downregulates the decoy receptor DcR1 through IL-8 signaling while upregulating pro-apoptotic death receptors DR4/5, thereby sensitizing cells - even with acquired TRAIL-resistance - to apoptosis induction. Treatment of orthotopic pancreatic cancer xenografts with either gemcitabine, JNKi or TRAIL alone for 4 weeks showed only modest effects compared to control, while the combination of JNKi and TRAIL resulted in significantly lower tumor burden (69%; p < 0.04), reduced numbers of circulating tumor cells, and less distant metastatic events, without affecting the general health of the animals. Conclusions The combination of JNKi and TRAIL significantly impacts on CSCs, but leaves regular tissue-resident stem cells unaffected – even under hypoxic stress conditions. This concept of selective treatment of pancreatic CSCs warrants further evaluation. PMID:26840266

  1. miR-126 Regulates Distinct Self-Renewal Outcomes in Normal and Malignant Hematopoietic Stem Cells

    PubMed Central

    Lechman, Eric R.; Gentner, Bernhard; Ng, Stanley W.K.; Schoof, Erwin M.; van Galen, Peter; Kennedy, James A.; Nucera, Silvia; Ciceri, Fabio; Kaufmann, Kerstin B.; Takayama, Naoya; Dobson, Stephanie M.; Trotman-Grant, Aaron; Krivdova, Gabriela; Elzinga, Janneke; Mitchell, Amanda; Nilsson, Björn; Hermans, Karin G.; Eppert, Kolja; Marke, Rene; Isserlin, Ruth; Voisin, Veronique; Bader, Gary D.; Zandstra, Peter W.; Golub, Todd R.; Ebert, Benjamin L.; Lu, Jun; Minden, Mark; Wang, Jean C.Y.; Naldini, Luigi; Dick, John E.

    2016-01-01

    Summary To investigate miRNA function in human acute myeloid leukemia (AML) stem cells (LSC), we generated a prognostic LSC-associated miRNA signature derived from functionally validated subpopulations of AML samples. For one signature miRNA, miR-126, high bioactivity aggregated all in vivo patient sample LSC activity into a single sorted population, tightly coupling miR-126 expression to LSC function. Through functional studies, miR-126 was found to restrain cell cycle progression, prevent differentiation, and increase self-renewal of primary LSC in vivo. Compared with prior results showing miR-126 regulation of normal hematopoietic stem cell (HSC) cycling, these functional stem effects are opposite between LSC and HSC. Combined transcriptome and proteome analysis demonstrates that miR-126 targets the PI3K/AKT/MTOR signaling pathway, preserving LSC quiescence and promoting chemotherapy resistance. PMID:26832662

  2. Genome-wide comparison of the transcriptomes of highly enriched normal and chronic myeloid leukemia stem and progenitor cell populations.

    PubMed

    Gerber, Jonathan M; Gucwa, Jessica L; Esopi, David; Gurel, Meltem; Haffner, Michael C; Vala, Milada; Nelson, William G; Jones, Richard J; Yegnasubramanian, Srinivasan

    2013-05-01

    The persistence leukemia stem cells (LSCs) in chronic myeloid leukemia (CML) despite tyrosine kinase inhibition (TKI) may explain relapse after TKI withdrawal. Here we performed genome-wide transcriptome analysis of highly refined CML and normal stem and progenitor cell populations to identify novel targets for the eradication of CML LSCs using exon microarrays. We identified 97 genes that were differentially expressed in CML versus normal stem and progenitor cells. These included cell surface genes significantly upregulated in CML LSCs: DPP4 (CD26), IL2RA (CD25), PTPRD, CACNA1D, IL1RAP, SLC4A4, and KCNK5. Further analyses of the LSCs revealed dysregulation of normal cellular processes, evidenced by alternative splicing of genes in key cancer signaling pathways such as p53 signaling (e.g. PERP, CDKN1A), kinase binding (e.g. DUSP12, MARCKS), and cell proliferation (MYCN, TIMELESS); downregulation of pro-differentiation and TGF-β/BMP signaling pathways; upregulation of oxidative metabolism and DNA repair pathways; and activation of inflammatory cytokines, including CCL2, and multiple oncogenes (e.g., CCND1). These data represent an important resource for understanding the molecular changes in CML LSCs, which may be exploited to develop novel therapies for eradication these cells and achieve cure.

  3. Proteomic Analysis of Mesenchymal Stem Cells from Normal and Deep Carious Dental Pulp

    PubMed Central

    Gao, Jie; Yan, Wenjuan; Liu, Ying; Xu, Shuaimei; Wu, Buling

    2014-01-01

    Dental pulp stem cells (DPSCs), precursor cells of odontoblasts, are ideal seed cells for tooth tissue engineering and regeneration. Our previous study has demonstrated that stem cells exist in dental pulp with deep caries and are called carious dental pulp stem cells (CDPSCs). The results indicated that CDPSCs had a higher proliferative and stronger osteogenic differentiation potential than DPSCs. However, the molecular mechanisms responsible for the biological differences between DPSCs and CDPSCs are poorly understood. The aim of this study was to define the molecular features of DPSCs and CDPSCs by comparing the proteomic profiles using two-dimensional fluorescence difference gel electrophoresis (2-D DIGE) in combination with matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS). Our results revealed that there were 18 protein spots differentially expressed between DPSCs and CDPSCs in a narrow pH range of 4 to 7. These differently expressed proteins are mostly involved in the regulation of cell proliferation, differentiation, cell cytoskeleton and motility. In addition, our results suggested that CDPSCs had a higher expression of antioxidative proteins that might protect CDPSCs from oxidative stress. This study explores some potential proteins responsible for the biological differences between DPSCs and CDPSCs and expands our understanding on the molecular mechanisms of mineralization of DPSCs in the formation of the dentin-pulp complex. PMID:24809979

  4. Growth hormone is secreted by normal breast epithelium upon progesterone stimulation and increases proliferation of stem/progenitor cells.

    PubMed

    Lombardi, Sara; Honeth, Gabriella; Ginestier, Christophe; Shinomiya, Ireneusz; Marlow, Rebecca; Buchupalli, Bharath; Gazinska, Patrycja; Brown, John; Catchpole, Steven; Liu, Suling; Barkan, Ariel; Wicha, Max; Purushotham, Anand; Burchell, Joy; Pinder, Sarah; Dontu, Gabriela

    2014-06-01

    Using in vitro and in vivo experimental systems and in situ analysis, we show that growth hormone (GH) is secreted locally by normal human mammary epithelial cells upon progesterone stimulation. GH increases proliferation of a subset of cells that express growth hormone receptor (GHR) and have functional properties of stem and early progenitor cells. In 72% of ductal carcinoma in situ lesions, an expansion of the cell population that expresses GHR was observed, suggesting that GH signaling may contribute to breast cancer development.

  5. Deubiquitinase MYSM1 Is Essential for Normal Bone Formation and Mesenchymal Stem Cell Differentiation

    PubMed Central

    Li, Ping; Yang, Yan-Mei; Sanchez, Suzi; Cui, Dian-Chao; Dang, Rui-Jie; Wang, Xiao-Yan; Lin, Qiu-Xia; Wang, Yan; Wang, Changyong; Chen, Da-Fu; Chen, Si-Yi; Jiang, Xiao-Xia; Wen, Ning

    2016-01-01

    Deubiquitinase MYSM1 has been shown to play a critical role in hematopoietic cell differentiation and hematopoietic stem cell (HSC) maintenance. Mesenchymal stem cells (MSCs) are multipotent stromal cells within the bone marrow. MSCs are progenitors to osteoblasts, chondrocytes, adipocytes, and myocytes. Although, MSCs have been extensively studied, the roles of MYSM1 in these cells remain unclear. Here we describe the function of MYSM1 on MSC maintenance and differentiation. In this report, we found that Mysm1−/− mice had a lower bone mass both in long bone and calvaria compared with their control counterpart. Preosteoblasts from Mysm1−/− mice did not show changes in proliferation or osteogenesis when compared to WT mice. Conversely, Mysm1−/− MSCs showed enhanced autonomous differentiation and accelerated adipogenesis. Our results demonstrate that MYSM1 plays a critical role in MSC maintenance and differentiation. This study also underscores the biological significance of deubiquitinase activity in MSC function. Mysm1 may represent a potential therapeutic target for controlling MSC lineage differentiation, and possibly for the treatment of metabolic bone diseases such as osteoporosis. PMID:26915790

  6. Stem Cell Basics

    MedlinePlus

    ... stem cells? What are the potential uses of human stem cells and the obstacles that must be overcome before ... two kinds of stem cells from animals and humans: embryonic stem cells and non-embryonic "somatic" or "adult" stem cells . ...

  7. Learn About Stem Cells

    MedlinePlus

    ... PDF) Download an introduction to stem cells and stem cell research. Stem Cell Glossary Stem cell terms to know. ... ISSCR Get Involved Media © 2015 International Society for Stem Cell Research Terms of Use Disclaimer Privacy Policy

  8. Residual normal stem cells can be detected in newly diagnosed chronic myeloid leukemia patients by a new flow cytometric approach and predict for optimal response to imatinib.

    PubMed

    Janssen, J J W M; Deenik, W; Smolders, K G M; van Kuijk, B J; Pouwels, W; Kelder, A; Cornelissen, J J; Schuurhuis, G J; Ossenkoppele, G J

    2012-05-01

    Insensitivity of chronic myeloid leukemia (CML) hematopoietic stem cells to tyrosine kinase inhibitors (TKIs) prevents eradication of the disease and may be involved in clinical resistance. For improved treatment results more knowledge about CML stem cells is needed. We here present a new flow cytometric approach enabling prospective discrimination of CML stem cells from their normal counterparts within single-patient samples. In 24 of 40 newly diagnosed CML patients residual normal CD34(+)CD38(-) stem cells could be identified by lower CD34 and CD45 expression, lower forward/sideward light scatter and by differences of lineage marker expression (CD7, CD11b and CD56) and of CD90. fluorescent in situ hybridization (FISH) analysis on Fluorescence-activated cell sorting sorted cells proved that populations were BCR-ABL positive or negative and long-term liquid culture assays with subsequent colony forming unit assays and FISH analysis proved their stem cell character. Patients with residual non-leukemic stem cells had lower clinical risk scores (Sokal, Euro), lower hematological toxicity of imatinib (IM) and better molecular responses to IM than patients without. This new approach will expand our possibilities to separate CML and normal stem cells, present in a single bone marrow or peripheral blood sample, thereby offering opportunities to better identify new CML stem-cell-specific targets. Moreover, it may guide optimal clinical CML management. PMID:22157734

  9. Polycythemia vera. The in vitro response of normal and abnormal stem cell lines to erythropoietin.

    PubMed Central

    Prchal, J F; Adamson, J W; Murphy, S; Steinmann, L; Fialkow, P J

    1978-01-01

    Bone marrow cells from two glucose-6-phosphate dehydrogenase (G-6-PD) heterozygotes with polycythemia vera were cultured to determine whether progenitors which wre not of the polycythemia vera clone were present, and, if present, which cell lines contributed to the increase in erythroid colonies observed in response to added erythropoietin (ESF). To accomplish this, the G-6-PD isoenzyme activity of individual erythroid colonies was determined. All of the erythroid colonies analyzed in cultures without added ESF, contained the G-6-PD isoenzyme type characteristic of the abnormal clone. With higher ESF concentrations in the culture, however, there was an increase in the colonies that were not of the polycythemia vera clone. Analysis of the ratio of the various types of colonies indicated that normal and polycythemia vera cells are capable of responding to ESF in vitro. In selected patients, this technique permits analysis of the ratios of normal to abnormal cells during the course of the disease, in response to therapy and during late complications, such as myelofibrosis or leukemic transformation. PMID:659576

  10. Difference in glycerol levels between leukemia and normal bone marrow stem cells

    PubMed Central

    QIN, YING-SONG; BU, DAN-XIA; CUI, YING-YING; ZHANG, XIANG-YU

    2014-01-01

    Aquaglyceroporin 9 (AQP9) is considered to be involved in numerous types of carcinogenic processes, particularly in liver carcinoma. AQP9 expression is significantly decreased in the human hepatocellular carcinoma when compared with the non-tumourigenic liver, which leads to increased resistance to apoptosis. In addition, AQP9 is permeable to glycerol and urea. The involvement of AQP9 in leukemia has not been fully delineated. It is proposed that abnormal proliferation of hematopoietic stem cells (HSCs) contributes to leukemia carcinogenesis. Therefore, the present study aimed to investigate the possible roles of AQP9 in HSCs and its effect on the intracellular glycerol content. HSCs and non-HSCs (nHSCs) were isolated via magnetic-activated cell sorting and then subjected to flow cytometry for evaluation of purity. White blood cells (WBCs) were isolated from peripheral blood from healthy volunteers. Furthermore, AQP9 expression was examined at the mRNA and protein levels using western blotting and reverse transcription-polymerase chain reaction (RT-PCR). The glycerol content of HSCs, nHSCs and WBCs was evaluated by ELISA. Finally, in order to observe the morphology of HSCs and nHSCs, a blood smear was conducted and the cells were observed with Wright-Giemsa staining. The results indicated that the glycerol content in the HSCs was markedly greater than that in the nHSCs. AQP9 mRNA and protein expression was not detected in the HSCs and nHSCs, but was identified in the WBCs. Moreover, the HSC morphological characteristics included round or oval cells with round, slightly oval or irregularly shaped nuclei. Additionally, the nuclei occupied almost the entire cell, were located in the middle or were biased toward one side, and were stained light purple or red. Overall, our results indicated that intracellular glycerol is involved in HSC proliferation, despite the fact that glycerol is not mediated by AQP9. Hence, our findings may be useful in further understanding the

  11. Hsa-miR-520d induces hepatoma cells to form normal liver tissues via a stemness-mediated process

    PubMed Central

    Tsuno, Satoshi; Wang, Xinhui; Shomori, Kohei; Hasegawa, Junichi; Miura, Norimasa

    2014-01-01

    The human ncRNA gene RGM249 regulates the extent of differentiation of cancer cells and the conversion of 293FT cells to hiPSCs. To identify the factors underlying this process, we investigated the effects of lentivirally inducing miR-520d expression in 293FT and HLF cells in vitro. Subsequently, we evaluated tumor formation in a xenograft model. Transformed HLF cells were Oct4 and Nanog positive within 24 h, showed p53 upregulation and hTERT downregulation, and mostly lost their migration abilities. After lentiviral infection, the cells were intraperitoneally injected into mice, resulting in benign teratomas (6%), the absence of tumors (87%) or differentiation into benign liver tissues (7%) at the injection site after 1 month. We are the first to demonstrate the loss of malignant properties in cancer cells in vivo through the expression of a single microRNA (miRNA). This miRNA successfully converted 293FT and hepatoma cells to hiPSC-like cells. The regulation of malignancy by miR-520d appears to be through the conversion of cancer cells to normal stem cells, maintaining p53 upregulation. PMID:24458129

  12. Brain tumor stem cells.

    PubMed

    Palm, Thomas; Schwamborn, Jens C

    2010-06-01

    Since the end of the 'no-new-neuron' theory, emerging evidence from multiple studies has supported the existence of stem cells in neurogenic areas of the adult brain. Along with this discovery, neural stem cells became candidate cells being at the origin of brain tumors. In fact, it has been demonstrated that molecular mechanisms controlling self-renewal and differentiation are shared between brain tumor stem cells and neural stem cells and that corruption of genes implicated in these pathways can direct tumor growth. In this regard, future anticancer approaches could be inspired by uncovering such redundancies and setting up treatments leading to exhaustion of the cancer stem cell pool. However, deleterious effects on (normal) neural stem cells should be minimized. Such therapeutic models underline the importance to study the cellular mechanisms implicated in fate decisions of neural stem cells and the oncogenic derivation of adult brain cells. In this review, we discuss the putative origins of brain tumor stem cells and their possible implications on future therapies.

  13. The Runx-PU.1 pathway preserves normal and AML/ETO9a leukemic stem cells.

    PubMed

    Staber, Philipp B; Zhang, Pu; Ye, Min; Welner, Robert S; Levantini, Elena; Di Ruscio, Annalisa; Ebralidze, Alexander K; Bach, Christian; Zhang, Hong; Zhang, Junyan; Vanura, Katrina; Delwel, Ruud; Yang, Henry; Huang, Gang; Tenen, Daniel G

    2014-10-01

    Runx transcription factors contribute to hematopoiesis and are frequently implicated in hematologic malignancies. All three Runx isoforms are expressed at the earliest stages of hematopoiesis; however, their function in hematopoietic stem cells (HSCs) is not fully elucidated. Here, we show that Runx factors are essential in HSCs by driving the expression of the hematopoietic transcription factor PU.1. Mechanistically, by using a knockin mouse model in which all three Runx binding sites in the -14kb enhancer of PU.1 are disrupted, we observed failure to form chromosomal interactions between the PU.1 enhancer and its proximal promoter. Consequently, decreased PU.1 levels resulted in diminished long-term HSC function through HSC exhaustion, which could be rescued by reintroducing a PU.1 transgene. Similarly, in a mouse model of AML/ETO9a leukemia, disrupting the Runx binding sites resulted in decreased PU.1 levels. Leukemia onset was delayed, and limiting dilution transplantation experiments demonstrated functional loss of leukemia-initiating cells. This is surprising, because low PU.1 levels have been considered a hallmark of AML/ETO leukemia, as indicated in mouse models and as shown here in samples from leukemic patients. Our data demonstrate that Runx-dependent PU.1 chromatin interaction and transcription of PU.1 are essential for both normal and leukemia stem cells.

  14. In Vivo Tracking of Systemically Administered Allogeneic Bone Marrow Mesenchymal Stem Cells in Normal Rats through Bioluminescence Imaging

    PubMed Central

    Cao, Juan; Hou, Shike; Ding, Hui; Liu, Ziquan; Song, Meijuan; Qin, Xiaojing; Wang, Xue; Yu, Mengyang; Sun, Zhiguang; Liu, Jinyang; Sun, Shuli; Xiao, Peixin

    2016-01-01

    Recently, mesenchymal stem cells (MSCs) are increasingly used as a panacea for multiple types of disease short of effective treatment. Dozens of clinical trials published demonstrated strikingly positive therapeutic effects of MSCs. However, as a specific agent, little research has focused on the dynamic distribution of MSCs after in vivo administration. In this study, we track systemically transplanted allogeneic bone marrow mesenchymal stem cells (BMSCs) in normal rats through bioluminescence imaging (BLI) in real time. Ex vivo organ imaging, immunohistochemistry (IHC), and RT-PCR were conducted to verify the histological distribution of BMSCs. Our results showed that BMSCs home to the dorsal skin apart from the lungs and kidneys after tail vein injection and could not be detected 14 days later. Allogeneic BMSCs mainly appeared not at the parenchymatous organs but at the subepidermal connective tissue and adipose tissue in healthy rats. There were no significant MSCs-related adverse effects except for transient decrease in neutrophils. These findings will provide experimental evidences for a better understanding of the biocharacteristics of BMSCs.

  15. In Vivo Tracking of Systemically Administered Allogeneic Bone Marrow Mesenchymal Stem Cells in Normal Rats through Bioluminescence Imaging.

    PubMed

    Cao, Juan; Hou, Shike; Ding, Hui; Liu, Ziquan; Song, Meijuan; Qin, Xiaojing; Wang, Xue; Yu, Mengyang; Sun, Zhiguang; Liu, Jinyang; Sun, Shuli; Xiao, Peixin; Lv, Qi; Fan, Haojun

    2016-01-01

    Recently, mesenchymal stem cells (MSCs) are increasingly used as a panacea for multiple types of disease short of effective treatment. Dozens of clinical trials published demonstrated strikingly positive therapeutic effects of MSCs. However, as a specific agent, little research has focused on the dynamic distribution of MSCs after in vivo administration. In this study, we track systemically transplanted allogeneic bone marrow mesenchymal stem cells (BMSCs) in normal rats through bioluminescence imaging (BLI) in real time. Ex vivo organ imaging, immunohistochemistry (IHC), and RT-PCR were conducted to verify the histological distribution of BMSCs. Our results showed that BMSCs home to the dorsal skin apart from the lungs and kidneys after tail vein injection and could not be detected 14 days later. Allogeneic BMSCs mainly appeared not at the parenchymatous organs but at the subepidermal connective tissue and adipose tissue in healthy rats. There were no significant MSCs-related adverse effects except for transient decrease in neutrophils. These findings will provide experimental evidences for a better understanding of the biocharacteristics of BMSCs. PMID:27610137

  16. In Vivo Tracking of Systemically Administered Allogeneic Bone Marrow Mesenchymal Stem Cells in Normal Rats through Bioluminescence Imaging

    PubMed Central

    Cao, Juan; Hou, Shike; Ding, Hui; Liu, Ziquan; Song, Meijuan; Qin, Xiaojing; Wang, Xue; Yu, Mengyang; Sun, Zhiguang; Liu, Jinyang; Sun, Shuli; Xiao, Peixin

    2016-01-01

    Recently, mesenchymal stem cells (MSCs) are increasingly used as a panacea for multiple types of disease short of effective treatment. Dozens of clinical trials published demonstrated strikingly positive therapeutic effects of MSCs. However, as a specific agent, little research has focused on the dynamic distribution of MSCs after in vivo administration. In this study, we track systemically transplanted allogeneic bone marrow mesenchymal stem cells (BMSCs) in normal rats through bioluminescence imaging (BLI) in real time. Ex vivo organ imaging, immunohistochemistry (IHC), and RT-PCR were conducted to verify the histological distribution of BMSCs. Our results showed that BMSCs home to the dorsal skin apart from the lungs and kidneys after tail vein injection and could not be detected 14 days later. Allogeneic BMSCs mainly appeared not at the parenchymatous organs but at the subepidermal connective tissue and adipose tissue in healthy rats. There were no significant MSCs-related adverse effects except for transient decrease in neutrophils. These findings will provide experimental evidences for a better understanding of the biocharacteristics of BMSCs. PMID:27610137

  17. 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

  18. Laser biomodulation on stem cells

    NASA Astrophysics Data System (ADS)

    Liu, Timon C.; Duan, Rui; Li, Yan; Li, Xue-Feng; Tan, Li-Ling; Liu, Songhao

    2001-08-01

    Stem cells are views from the perspectives of their function, evolution, development, and cause. Counterintuitively, most stem cells may arise late in development, to act principally in tissue renewal, thus ensuring an organisms long-term survival. Surprisingly, recent reports suggest that tissue-specific adult stem cells have the potential to contribute to replenishment of multiple adult tissues. Stem cells are currently in the news for two reasons: the successful cultivation of human embryonic stem cell lines and reports that adult stem cells can differentiate into developmentally unrelated cell types, such as nerve cells into blood cells. The spotlight on stem cells has revealed gaps in our knowledge that must be filled if we are to take advantage of their full potential for treating devastating degenerative diseases such as Parkinsons's disease and muscular dystrophy. We need to know more about the intrinsic controls that keep stem cells as stem cells or direct them along particular differentiation pathways. Such intrinsic regulators are, in turn, sensitive to the influences of the microenvironment, or niche, where stem cells normally reside. Both intrinsic and extrinsic signals regular stem cell fate and some of these signals have now been identified. Vacek et al and Wang et al have studied the effect of low intensity laser on the haemopoietic stem cells in vitro. There experiments show there is indeed the effect of low intensity laser on the haemopoietic stem cells in vitro, and the present effect is the promotion of haemopoietic stem cells proliferation. In other words, low intensity laser irradiation can act as an extrinsic signal regulating stem cell fate. In this paper, we study how low intensity laser can be used to regulate stem cell fate from the viewpoint of collective phototransduction.

  19. Kinetics and regulation of human keratinocyte stem cell growth in short-term primary ex vivo culture. Cooperative growth factors from psoriatic lesional T lymphocytes stimulate proliferation among psoriatic uninvolved, but not normal, stem keratinocytes.

    PubMed Central

    Bata-Csorgo, Z; Hammerberg, C; Voorhees, J J; Cooper, K D

    1995-01-01

    Flow cytometric analysis of primary ex vivo keratinocyte cultures demonstrated that stem cells, (beta 1 integrin+, keratin 1/keratin 10 [K1/K10-], proliferating cell nuclear antigen [PCNA-] [Bata-Csorgo, Zs., C. Hammerberg, J. J. Voorhees, and K. D. Cooper. 1993. J. Exp. Med. 178:1271-1281]) establish such cultures. This methodology also enabled the quantitation of synchronized recruitment of these cells from G0 into G1 of the cell cycle (PCNA expression), which preceded bright beta 1 integrin expression. (beta 1 integrinbright expression has been shown to be a characteristic feature of keratinocyte stem cells in culture (Jones, P. H., and F. M. Watt. 1993. Cell. 73:713-724). Using the above assay, we determined whether lesional T lymphocytes in psoriasis could be directly responsible for the induction of the stem cell hyperproliferation that is characteristic of this disease. Indeed, CD4+ T lymphocytes, cloned from lesional psoriatic skin and stimulated by immobilized anti-CD3 plus fibronectin, promoted psoriatic uninvolved keratinocyte stem cell proliferation via soluble factors. This induction appeared to be through accelerated recruitment of stem cells from their quiescent state (G0) into cell cycle. By contrast, normal keratinocyte stem cells exhibited no such growth stimulation. Supernatants exhibiting growth induction all contained high levels of GM-CSF and gamma-IFN, low IL-3 and TNF-alpha, and variable IL-4. Only anti-gamma-IFN antibody was able to neutralize growth stimulatory activity of the supernatants on psoriatic uninvolved keratinocyte stem cells. However, because recombinant gamma-IFN alone inhibited growth in this assay, these data suggest that, in psoriasis, gamma-IFN acts cooperatively with other growth factors in the immune induction of cell cycle progression by the normally quiescent stem cell keratinocytes. Images PMID:7529261

  20. Stem Cell Research

    SciTech Connect

    Verfaillie, Catherine

    2009-01-23

    We have identified a population of primitive cells in normal human post-natal bone marrow that can, at the single cell level, differentiate in many ways and also proliferate extensively. These cells can differentiate in vitro into most mesodermal cell types (for example, bone cells, and others), as well as cells into cells of the nervous system. The finding that stem cells exist in post-natal tissues with previously unknown proliferation and differentiation potential opens up the possibility of using them to treat a host of degenerative, traumatic or congenital diseases.

  1. Stem Cell Research

    SciTech Connect

    Verfaillie, Catherine

    2002-01-23

    We have identified a population of primitive cells in normal human post-natal bone marrow that can, at the single cell level, differentiate in many ways and also proliferate extensively. These cells can differentiate in vitro into most mesodermal cell types (for example, bone cells, and others), as well as cells into cells of the nervous system. The finding that stem cells exist in post-natal tissues with previously unknown proliferation and differentiation potential opens up the possibility of using them to treat a host of degenerative, traumatic or congenital diseases.

  2. Melanocytes, melanocyte stem cells, and melanoma stem cells.

    PubMed

    Lang, Deborah; Mascarenhas, Joseph B; Shea, Christopher R

    2013-01-01

    Melanocyte stem cells differ greatly from melanoma stem cells; the former provide pigmented cells during normal tissue homeostasis and repair, and the latter play an active role in a lethal form of cancer. These 2 cell types share several features and can be studied by similar methods. Aspects held in common by both melanocyte stem cells and melanoma stem cells include their expression of shared biochemical markers, a system of similar molecular signals necessary for their maintenance, and a requirement for an ideal niche microenvironment for providing these factors. This review provides a perspective of both these cell types and discusses potential models of stem cell growth and propagation. Recent findings provide a strong foundation for the development of new therapeutics directed at isolating and manipulating melanocyte stem cells for tissue engineering or at targeting and eradicating melanoma specifically, while sparing nontumor cells.

  3. Differential Proteomic Analysis of Human Placenta-Derived Mesenchymal Stem Cells Cultured on Normal Tissue Culture Surface and Hyaluronan-Coated Surface

    PubMed Central

    Wong, Tzyy Yue; Chen, Ying-Hui; Liu, Szu-Heng; Solis, Mairim Alexandra; Yu, Chen-Hsiang; Chang, Chiung-Hsin; Huang, Lynn L. H.

    2016-01-01

    Our previous results showed that hyaluronan (HA) preserved human placenta-derived mesenchymal stem cells (PDMSC) in a slow cell cycling mode similar to quiescence, the pristine state of stem cells in vivo, and HA was found to prevent murine adipose-derived mesenchymal stem cells from senescence. Here, stable isotope labeling by amino acid in cell culture (SILAC) proteomic profiling was used to evaluate the effects of HA on aging phenomenon in stem cells, comparing (1) old and young passage PDMSC cultured on normal tissue culture surface (TCS); (2) old passage on HA-coated surface (CHA) compared to TCS; (3) old and young passage on CHA. The results indicated that senescence-associated protein transgelin (TAGLN) was upregulated in old TCS. Protein CYR61, reportedly senescence-related, was downregulated in old CHA compared to old TCS. The SIRT1-interacting Nicotinamide phosphoribosyltransferase (NAMPT) increased by 2.23-fold in old CHA compared to old TCS, and is 0.48-fold lower in old TCS compared to young TCS. Results also indicated that components of endoplasmic reticulum associated degradation (ERAD) pathway were upregulated in old CHA compared to old TCS cells, potentially for overcoming stress to maintain cell function and suppress senescence. Our data points to pathways that may be targeted by HA to maintain stem cells youth. PMID:27057169

  4. Differential Proteomic Analysis of Human Placenta-Derived Mesenchymal Stem Cells Cultured on Normal Tissue Culture Surface and Hyaluronan-Coated Surface.

    PubMed

    Wong, Tzyy Yue; Chen, Ying-Hui; Liu, Szu-Heng; Solis, Mairim Alexandra; Yu, Chen-Hsiang; Chang, Chiung-Hsin; Huang, Lynn L H

    2016-01-01

    Our previous results showed that hyaluronan (HA) preserved human placenta-derived mesenchymal stem cells (PDMSC) in a slow cell cycling mode similar to quiescence, the pristine state of stem cells in vivo, and HA was found to prevent murine adipose-derived mesenchymal stem cells from senescence. Here, stable isotope labeling by amino acid in cell culture (SILAC) proteomic profiling was used to evaluate the effects of HA on aging phenomenon in stem cells, comparing (1) old and young passage PDMSC cultured on normal tissue culture surface (TCS); (2) old passage on HA-coated surface (CHA) compared to TCS; (3) old and young passage on CHA. The results indicated that senescence-associated protein transgelin (TAGLN) was upregulated in old TCS. Protein CYR61, reportedly senescence-related, was downregulated in old CHA compared to old TCS. The SIRT1-interacting Nicotinamide phosphoribosyltransferase (NAMPT) increased by 2.23-fold in old CHA compared to old TCS, and is 0.48-fold lower in old TCS compared to young TCS. Results also indicated that components of endoplasmic reticulum associated degradation (ERAD) pathway were upregulated in old CHA compared to old TCS cells, potentially for overcoming stress to maintain cell function and suppress senescence. Our data points to pathways that may be targeted by HA to maintain stem cells youth. PMID:27057169

  5. Stem Cell Sciences plc.

    PubMed

    Daniels, Sebnem

    2006-09-01

    Stem Cell Sciences' core objective is to develop safe and effective stem cell-based therapies for currently incurable diseases. In order to achieve this goal, Stem Cell Sciences recognizes the need for multiple technologies and a globally integrated stem cell initiative. The key challenges for the successful application of stem cells in the clinic is the need for a reproducible supply of pure, fully characterized stem cells that have been grown in suitable conditions for use in the clinic.

  6. Regulation of endogenous neural stem/progenitor cells for neural repair-factors that promote neurogenesis and gliogenesis in the normal and damaged brain.

    PubMed

    Christie, Kimberly J; Turnley, Ann M

    2012-01-01

    Neural stem/precursor cells in the adult brain reside in the subventricular zone (SVZ) of the lateral ventricles and the subgranular zone (SGZ) of the dentate gyrus in the hippocampus. These cells primarily generate neuroblasts that normally migrate to the olfactory bulb (OB) and the dentate granule cell layer respectively. Following brain damage, such as traumatic brain injury, ischemic stroke or in degenerative disease models, neural precursor cells from the SVZ in particular, can migrate from their normal route along the rostral migratory stream (RMS) to the site of neural damage. This neural precursor cell response to neural damage is mediated by release of endogenous factors, including cytokines and chemokines produced by the inflammatory response at the injury site, and by the production of growth and neurotrophic factors. Endogenous hippocampal neurogenesis is frequently also directly or indirectly affected by neural damage. Administration of a variety of factors that regulate different aspects of neural stem/precursor biology often leads to improved functional motor and/or behavioral outcomes. Such factors can target neural stem/precursor proliferation, survival, migration and differentiation into appropriate neuronal or glial lineages. Newborn cells also need to subsequently survive and functionally integrate into extant neural circuitry, which may be the major bottleneck to the current therapeutic potential of neural stem/precursor cells. This review will cover the effects of a range of intrinsic and extrinsic factors that regulate neural stem/precursor cell functions. In particular it focuses on factors that may be harnessed to enhance the endogenous neural stem/precursor cell response to neural damage, highlighting those that have already shown evidence of preclinical effectiveness and discussing others that warrant further preclinical investigation. PMID:23346046

  7. Normalization of wound healing and stem cell marker patterns in organ-cultured human diabetic corneas by gene therapy of limbal cells.

    PubMed

    Saghizadeh, Mehrnoosh; Dib, Christian M; Brunken, William J; Ljubimov, Alexander V

    2014-12-01

    Overexpression of c-met and suppression of matrix metalloproteinase-10 (MMP-10) and cathepsin F genes was previously shown to normalize wound healing, epithelial and stem cell marker patterns in organ-cultured human diabetic corneas. We now examined if gene therapy of limbal cells only would produce similar effects. Eight pairs of organ-cultured autopsy human diabetic corneas were used. One cornea of each pair was treated for 48 h with adenoviruses (Ad) harboring full-length c-met mRNA or a mixture (combo) of Ad with c-met and shRNA to MMP-10 and cathepsin F genes. Medium was kept at the limbal level to avoid transduction of central corneal epithelium. Fellow corneas received control Ad with EGFP gene. After additional 5 (c-met) or 10 days (combo) incubation, central corneal epithelial debridement with n-heptanol was performed, and wound healing times were determined microscopically. Corneal cryostat sections were immunostained for diabetic and putative limbal stem cell markers, α3β1 integrin, nidogen-1, fibronectin, laminin γ3 chain, ΔNp63α, keratins 14, 15, and 17, as well as for activated signaling intermediates, phosphorylated EGFR, Akt, and p38. Limbal c-met overexpression significantly accelerated healing of 8.5-mm epithelial wounds over EGFP controls (6.3 days vs. 9.5 days, p < 0.02). Combo treatment produced a similar result (6.75 days vs. 13.5 days, p < 0.03). Increased immunostaining vs. EGFP controls for most markers and signaling intermediates accompanied c-met gene or combo transduction. Gene therapy of limbal epithelial stem cell compartment has a beneficial effect on the diabetic corneal wound healing and on diabetic and stem cell marker expression, and shows potential for alleviating symptoms of diabetic keratopathy.

  8. A comparison of the response to hyperthermia of murine haemopoietic stem cells (CFU-S) and L1210 leukaemia cells: enhanced killing of leukaemic cells in presence of normal marrow cells.

    PubMed Central

    Symonds, R. P.; Wheldon, T. E.; Clarke, B.; Bailey, G.

    1981-01-01

    When the clonogenic survival of mouse haemopoietic stem cells (CFU-S) and leukaemia L1210 cells growth as ascites tumours are compared after being heated in vitro and assayed in vivo by spleen-colony assay, there is no significant difference in the terminal slopes of the survival curves. The shoulders of the survival curves differ, but this may be explained by differences in cell kinetics. By contrast, L1210 leukaemic marrow cells are considerably more susceptible to the lethal effects of hyperthermia (43 degrees C) than either normal marrow stem cells or L1210 leukaemic cells grown as ascites tumours. Moreover, the killing of L1210 ascites cells by hyperthermia can be enhanced by heating L1210 ascites cells with an equal number of normal marrow cells, or as upernatant removed from heated marrow cells. Most cells in lukaemic marrow are normal, and it is postulated that the increased thermal sensitivity of L1210 cells in leukaemic marrow is caused by diffusible factors (e.g. lysosomal enzymes) released by heating normal marrow cells. Images Fig. 8 Fig. 9 PMID:7317271

  9. Full reconstitution of the immune deficiency in scid mice with normal stem cells requires low-dose irradiation of the recipients

    SciTech Connect

    Fulop, G.M.; Phillips, R.A.

    1986-06-15

    Mice homozygous for an autosomal recessive mutation for the scid gene exhibit a defect that specifically impairs lymphoid differentiation but not myelopoiesis. Such mice can be cured of their lymphoid deficiency by grafts with normal bone marrow, although full reconstitution of lymphoid function is seldom obtained. Long-term bone marrow cultures (LTBMC) are devoid of all mature B and pre-B cells but contain lymphoid stem cells. We therefore reconstituted scid mice with LTBMC cells to study the kinetics of B lymphocyte reconstitution in normal and irradiated (4 Gy) scid recipients and in irradiated (9.5 Gy) co-isogenic C.B-17 mice. Detectable colony-forming B cells rapidly increased in the spleen and bone marrow of irradiated C.B-17 and irradiated scid recipients, reaching normal levels between 4 and 6 wk post-grafting. Unirradiated scid recipients showed limited reconstitution in spleen and very poor reconstitution in bone marrow. Unirradiated scid recipients also had relatively few surface Ig+ cells in spleen or bone marrow, whereas both groups of irradiated recipients had normal numbers between 4 and 6 wk post-reconstitution. Normal levels of cytotoxic T cell activity by 8 wk after reconstitution were observed only in the irradiated C.B-17 and irradiated scid recipients. Analysis of mice reconstituted with cells from LTBMC indicates that these cultures contain lymphoid stem cells with significant proliferative and self-renewal potential, and that full reconstitution of lymphoid function requires prior irradiation of the scid recipient.

  10. A comparison of tissue engineering based repair of calvarial defects using adipose stem cells from normal and osteoporotic rats

    PubMed Central

    Pei, Ming; Li, Jingting; McConda, David B.; Wen, Sijin; Clovis, Nina B.; Danley, Suzanne S.

    2015-01-01

    Repairing large bone defects presents a significant challenge, especially in those people who have a limited regenerative capacity such as in osteoporotic (OP) patients. The aim of this study was to compare adipose stem cells (ASCs) from both normal (NORM) and ovariectomized (OVX) rats in osteogenic potential using both in vitro and in vivo models. After successful establishment of a rat OP model, we found that ASCs from OVX rats exhibited a comparable proliferation capacity to those from NORM rats but had significantly higher adipogenic and relatively lower osteogenic potential. Thirty-two weeks post-implantation with poly (lactic-co-glycolic acid) (PLGA) alone or PLGA seeded with osteogenic-induced ASCs for critical-size calvarial defects, the data from Herovici’s collagen staining and micro-computed tomography suggested that the implantation of ASC-PLGA constructs exhibited a higher bone volume density compared to the PLGA alone group, especially in the NORM rat group. Intriguingly, the defects from OVX rats exhibited a higher bone volume density compared to NORM rats, especially for implantation of the PLGA alone group. Our results indicated that ASC based tissue constructs are more beneficial for the repair of calvarial defects in NORM rats while implantation of PLGA scaffold contributed to defect regeneration in OVX rats. PMID:25940459

  11. A comparison of tissue engineering based repair of calvarial defects using adipose stem cells from normal and osteoporotic rats.

    PubMed

    Pei, Ming; Li, Jingting; McConda, David B; Wen, Sijin; Clovis, Nina B; Danley, Suzanne S

    2015-09-01

    Repairing large bone defects presents a significant challenge, especially in those people who have a limited regenerative capacity such as in osteoporotic (OP) patients. The aim of this study was to compare adipose stem cells (ASCs) from both normal (NORM) and ovariectomized (OVX) rats in osteogenic potential using both in vitro and in vivo models. After successful establishment of a rat OP model, we found that ASCs from OVX rats exhibited a comparable proliferation capacity to those from NORM rats but had significantly higher adipogenic and relatively lower osteogenic potential. Thirty-two weeks post-implantation with poly(lactic-co-glycolic acid) (PLGA) alone or PLGA seeded with osteogenic-induced ASCs for critical-size calvarial defects, the data from Herovici's collagen staining and micro-computed tomography suggested that the implantation of ASC-PLGA constructs exhibited a higher bone volume density compared to the PLGA alone group, especially in the NORM rat group. Intriguingly, the defects from OVX rats exhibited a higher bone volume density compared to NORM rats, especially for implantation of the PLGA alone group. Our results indicated that ASC based tissue constructs are more beneficial for the repair of calvarial defects in NORM rats while implantation of PLGA scaffold contributed to defect regeneration in OVX rats.

  12. Specific combinations of the chromatin-modifying enzyme modulators significantly attenuate glioblastoma cell proliferation and viability while exerting minimal effect on normal adult stem cells growth.

    PubMed

    Alexanian, Arshak R; Huang, Yi-Wen

    2015-11-01

    The discoveries of recent decade showed that all critical changes in cancer cells, such as silencing of tumor-suppressor genes and activation of oncogenes, are caused not only by genetic but also by epigenetic mechanisms. Although epigenetic changes are somatically heritable, in contrast to genetic changes, they are potentially reversible, making them good targets for therapeutic intervention. Covalent modifications of chromatin such as methylation and acetylation of histones and methylation of DNA are the important components of epigenetic machinery. In this study, we investigated the effect of different modulators of DNA and histone covalent-modifying enzymes on the proliferation and viability of normal adult stem cells, such as human bone marrow mesenchymal stem cells (hMSCs), and on malignant tumor cells, such as glioblastoma (GB) D54 cells. Results demonstrated that specific combinations of histone methyltransferases and deacetylases inhibitors significantly attenuated D54 cells viability but having only a small effect on hMSCs growth. Taken together, these studies suggest that specific combinations of histone covalent modifiers could be an effective treatment option for the most aggressive type of primary brain tumors such as glioblastoma multiforme.

  13. Stem cell biobanks.

    PubMed

    Bardelli, Silvana

    2010-04-01

    Stem cells contribute to innate healing and harbor a promising role for regenerative medicine. Stem cell banking through long-term storage of different stem cell platforms represents a fundamental source to preserve original features of stem cells for patient-specific clinical applications. Stem cell research and clinical translation constitute fundamental and indivisible modules catalyzed through biobanking activity, generating a return of investment. PMID:20560026

  14. Effect of ROCK inhibitor Y-27632 on normal and variant human embryonic stem cells (hESCs) in vitro: its benefits in hESC expansion.

    PubMed

    Gauthaman, Kalamegam; Fong, Chui-Yee; Bongso, Ariff

    2010-03-01

    The Rho associated coiled coil protein kinase (ROCK) dependent signaling pathway plays an important role in numerous physiological functions such as cell proliferation, adhesion, migration and inflammation. Human embryonic stem cells (hESCs) undergo differentiation and poor survival after single cell dissociation in culture thus limiting their expansion for cell based therapies. We evaluated the role of the selective ROCK inhibitor Y-27632 on hESC colonies and disassociated single hESCs from two different hESC lines. Karyotypically normal hESCs (HES3) and variant hESCs (BG01V) were treated with Y-27632 at 5, 10 and 20 muM concentrations for 72 h and its effects on hESC self renewal, colony morphology, cell cycle and pluripotency were evaluated. Increased cell proliferation of both HES3 and BG01V were observed for all three concentrations compared to untreated controls following passaging of cell clusters or dissociated single cells and some of these increases were statistically significant. Cell cycle assay demonstrated normal cell cycle progression with no peaks evident of apoptosis. No morphological differentiation was evident following treatment with the highest concentration of Y-27632 (20 muM) and the stemness related genes continued to be highly expressed in both HES3 and BG01V cells compared to untreated controls. The results confirmed that Y-27632 is a useful agent that aids in the expansion of undifferentiated hESC numbers for downstream applications in regenerative medicine.

  15. 9-O-acetylated sialic acids differentiating normal haematopoietic precursors from leukemic stem cells with high aldehyde dehydrogenase activity in children with acute lymphoblastic leukaemia.

    PubMed

    Chowdhury, Suchandra; Chandra, Sarmila; Mandal, Chitra

    2014-10-01

    Childhood acute lymphoblastic leukaemia (ALL) originates from mutations in haematopoietic progenitor cells (HPCs). For high-risk patients, treated with intensified post-remission chemotherapy, haematopoietic stem cell (HSC) transplantation is considered. Autologous HSC transplantation needs improvisation till date. Previous studies established enhanced disease-associated expression of 9-O-acetylated sialoglycoproteins (Neu5,9Ac2-GPs) on lymphoblasts of these patients at diagnosis, followed by its decrease with clinical remission and reappearance with relapse. Based on this differential expression of Neu5,9Ac2-GPs, identification of a normal HPC population was targeted from patients at diagnosis. This study identifies two distinct haematopoietic progenitor populations from bone marrow of diagnostic ALL patients, exploring the differential expression of Neu5,9Ac2-GPs with stem cell (CD34, CD90, CD117, CD133), haematopoietic (CD45), lineage-commitment (CD38) antigens and cytosolic aldehyde dehydrogenase (ALDH). Normal haematopoietic progenitor cells (ALDH(+)SSC(lo)CD45(hi)Neu5,9Ac2 -GPs(lo)CD34(+)CD38(-)CD90(+)CD117(+)CD133(+)) differentiated into morphologically different, lineage-specific colonies, being crucial for autologous HSC transplantation while leukemic stem cells (ALDH(+)SSC(lo)CD45(lo)Neu5,9Ac2 -GPs(hi)CD34(+)CD38(+)CD90(-)CD117(-)CD133(-)) lacking this ability can be potential targets for minimal residual disease detection and drug-targeted immunotherapy.

  16. Exercise protects against obesity induced semen abnormalities via downregulating stem cell factor, upregulating Ghrelin and normalizing oxidative stress

    PubMed Central

    Alhashem, Fahaid; Alkhateeb, Mahmoud; Sakr, Hussein; Alshahrani, Mesfer; Alsunaidi, Mohammad; Elrefaey, Hesham; Alessa, Riyad; Sarhan, Mohammad; Eleawa, Samy M; Khalil, Mohammad A.

    2014-01-01

    Increased oxidative stress and hormonal imbalance have been hypothesized to underlie infertility in obese animals. However, recent evidence suggests that Ghrelin and Stem Cell Factor (SCF) play an important role in fertility, in lean individuals. Therefore, this study aimed at investigating whether changes in the levels of Ghrelin and SCF in rat testes underlie semen abnormal parameters observed in obese rats, and secondly, whether endurance exercise or Orlistat can protect against changes in Ghrelin, SCF, and/or semen parameters in diet induced obese rats. Obesity was modelled in male Wistar rats using High Fat Diet (HFD) 12-week protocol. Eight week-old rats (n=40) were divided into four groups, namely, Group I: fed with a standard diet (12 % of calories as fat); Group II: fed HFD (40 % of calories as fat); Group III: fed the HFD with a concomitant dose of Orlistat (200 mg/kg); and Group IV: fed the HFD and underwent 30 min daily swimming exercise. The model was validated by measuring the levels of testosterone, FSH, LH, estradiol, leptin, triglycerides, total, HDL, and LDL cholesterol, and final change in body weight. Levels were consistent with published obesity models (see Results). As predicted, the HFD group had a 76.8 % decrease in sperm count, 44.72 % decrease in sperm motility, as well as 47.09 % increase in abnormal sperm morphology. Unlike the control group, in the HFD group (i.e. obese rats) Ghrelin mRNA and protein were elevated, while SCF mRNA and protein were diminished in the testes. Furthermore, in the HFD group, SOD and GPx activities were significantly reduced, 48.5±5.8 % (P=0.0012) and 45.6±4.6 % (P=0.0019), respectively, while TBARS levels were significantly increased (112.7±8.9 %, P=0.0001). Finally, endurance exercise training and Orlistat administration individually and differentially protected semen parameters in obese rats. The mechanism includes, but is not limited to, normalizing the levels of Ghrelin, SCF, SOD, GPx and TBARS. In rat

  17. Exercise protects against obesity induced semen abnormalities via downregulating stem cell factor, upregulating Ghrelin and normalizing oxidative stress.

    PubMed

    Alhashem, Fahaid; Alkhateeb, Mahmoud; Sakr, Hussein; Alshahrani, Mesfer; Alsunaidi, Mohammad; Elrefaey, Hesham; Alessa, Riyad; Sarhan, Mohammad; Eleawa, Samy M; Khalil, Mohammad A

    2014-01-01

    Increased oxidative stress and hormonal imbalance have been hypothesized to underlie infertility in obese animals. However, recent evidence suggests that Ghrelin and Stem Cell Factor (SCF) play an important role in fertility, in lean individuals. Therefore, this study aimed at investigating whether changes in the levels of Ghrelin and SCF in rat testes underlie semen abnormal parameters observed in obese rats, and secondly, whether endurance exercise or Orlistat can protect against changes in Ghrelin, SCF, and/or semen parameters in diet induced obese rats. Obesity was modelled in male Wistar rats using High Fat Diet (HFD) 12-week protocol. Eight week-old rats (n=40) were divided into four groups, namely, Group I: fed with a standard diet (12 % of calories as fat); Group II: fed HFD (40 % of calories as fat); Group III: fed the HFD with a concomitant dose of Orlistat (200 mg/kg); and Group IV: fed the HFD and underwent 30 min daily swimming exercise. The model was validated by measuring the levels of testosterone, FSH, LH, estradiol, leptin, triglycerides, total, HDL, and LDL cholesterol, and final change in body weight. Levels were consistent with published obesity models (see Results). As predicted, the HFD group had a 76.8 % decrease in sperm count, 44.72 % decrease in sperm motility, as well as 47.09 % increase in abnormal sperm morphology. Unlike the control group, in the HFD group (i.e. obese rats) Ghrelin mRNA and protein were elevated, while SCF mRNA and protein were diminished in the testes. Furthermore, in the HFD group, SOD and GPx activities were significantly reduced, 48.5±5.8 % (P=0.0012) and 45.6±4.6 % (P=0.0019), respectively, while TBARS levels were significantly increased (112.7±8.9 %, P=0.0001). Finally, endurance exercise training and Orlistat administration individually and differentially protected semen parameters in obese rats. The mechanism includes, but is not limited to, normalizing the levels of Ghrelin, SCF, SOD, GPx and TBARS. In rat

  18. Bone regeneration and stem cells

    PubMed Central

    Arvidson, K; Abdallah, B M; Applegate, L A; Baldini, N; Cenni, E; Gomez-Barrena, E; Granchi, D; Kassem, M; Konttinen, Y T; Mustafa, K; Pioletti, D P; Sillat, T; Finne-Wistrand, A

    2011-01-01

    Abstract This invited review covers research areas of central importance for orthopaedic and maxillofacial bone tissue repair, including normal fracture healing and healing problems, biomaterial scaffolds for tissue engineering, mesenchymal and foetal stem cells, effects of sex steroids on mesenchymal stem cells, use of platelet-rich plasma for tissue repair, osteogenesis and its molecular markers. A variety of cells in addition to stem cells, as well as advances in materials science to meet specific requirements for bone and soft tissue regeneration by addition of bioactive molecules, are discussed. PMID:21129153

  19. Stem Cell Research.

    PubMed

    Trounson, Alan; Kolaja, Kyle; Petersen, Thomas; Weber, Klaus; McVean, Maralee; Funk, Kathleen A

    2015-01-01

    Stem cells have great potential in basic research and are being slowly integrated into toxicological research. This symposium provided an overview of the state of the field, stem cell models, described allogenic stem cell treatments and issues of immunogenicity associated with protein therapeutics, and tehn concentrated on stem cell uses in regenerative medicine focusing on lung and testing strategies on engineered tissues from a pathologist's perspective.

  20. ELMO1 Is Upregulated in AML CD34+ Stem/Progenitor Cells, Mediates Chemotaxis and Predicts Poor Prognosis in Normal Karyotype AML

    PubMed Central

    Capala, Marta E.; Vellenga, Edo; Schuringa, Jan Jacob

    2014-01-01

    Both normal as well leukemic hematopoietic stem cells critically depend on their microenvironment in the bone marrow for processes such as self-renewal, survival and differentiation, although the exact pathways that are involved remain poorly understood. We performed transcriptome analysis on primitive CD34+ acute myeloid leukemia (AML) cells (n = 46), their more differentiated CD34− leukemic progeny, and normal CD34+ bone marrow cells (n = 31) and focused on differentially expressed genes involved in adhesion and migration. Thus, Engulfment and Motility protein 1 (ELMO1) was identified amongst the top 50 most differentially expressed genes. ELMO1 is a crucial link in the signaling cascade that leads to activation of RAC GTPases and cytoskeleton rearrangements. We confirmed increased ELMO1 expression at the mRNA and protein level in a panel of AML samples and showed that high ELMO1 expression is an independent negative prognostic factor in normal karyotype (NK) AML in three large independent patient cohorts. Downmodulation of ELMO1 in human CB CD34+ cells did not significantly alter expansion, progenitor frequency or differentiation in stromal co-cultures, but did result in a decreased frequency of stem cells in LTC-IC assays. In BCR-ABL-transduced human CB CD34+ cells depletion of ELMO1 resulted in a mild decrease in proliferation, but replating capacity of progenitors was severely impaired. Downregulation of ELMO1 in a panel of primary CD34+ AML cells also resulted in reduced long-term growth in stromal co-cultures in two out of three cases. Pharmacological inhibition of the ELMO1 downstream target RAC resulted in a severely impaired proliferation and survival of leukemic cells. Finally, ELMO1 depletion caused a marked decrease in SDF1-induced chemotaxis of leukemic cells. Taken together, these data show that inhibiting the ELMO1-RAC axis might be an alternative way to target leukemic cells. PMID:25360637

  1. Information on Stem Cell Research

    MedlinePlus

    ... Enhancing Diversity Find People About NINDS Information on Stem Cell Research Research @ NINDS Stem Cell Highlights Submit a hESC ... found here: Human Induced Pluripotent Stem Cells NINDS Stem Cell Research on Campus The Intramural Research Program of NINDS ...

  2. Plant stem cell niches.

    PubMed

    Aichinger, Ernst; Kornet, Noortje; Friedrich, Thomas; Laux, Thomas

    2012-01-01

    Multicellular organisms possess pluripotent stem cells to form new organs, replenish the daily loss of cells, or regenerate organs after injury. Stem cells are maintained in specific environments, the stem cell niches, that provide signals to block differentiation. In plants, stem cell niches are situated in the shoot, root, and vascular meristems-self-perpetuating units of organ formation. Plants' lifelong activity-which, as in the case of trees, can extend over more than a thousand years-requires that a robust regulatory network keep the balance between pluripotent stem cells and differentiating descendants. In this review, we focus on current models in plant stem cell research elaborated during the past two decades, mainly in the model plant Arabidopsis thaliana. We address the roles of mobile signals on transcriptional modules involved in balancing cell fates. In addition, we discuss shared features of and differences between the distinct stem cell niches of Arabidopsis.

  3. Artificial Stem Cell Niches

    PubMed Central

    Lutolf, Matthias P.; Blau, Helen M.

    2011-01-01

    Stem cells are characterized by their dual ability to reproduce themselves (self-renew) and specialize (differentiate), yielding a plethora of daughter cells that maintain and regenerate tissues. In contrast to their embryonic counterparts, adult stem cells retain their unique functions only if they are in intimate contact with an instructive microenvironment, termed stem cell niche. In these niches, stem cells integrate a complex array of molecular signals that, in concert with induced cell-intrinsic regulatory networks, control their function and balance their numbers in response to physiologic demands. This progress report provides a perspective on how advanced materials technologies could be used (i) to engineer and systematically analyze specific aspects of functional stem cells niches in a controlled fashion in vitro and (ii) to target stem cell niches in vivo. Such “artificial niches” constitute potent tools for elucidating stem cell regulatory mechanisms with the capacity to directly impact the development of novel therapeutic strategies for tissue regeneration. PMID:20882496

  4. Stem Cell Information: Glossary

    MedlinePlus

    ... based therapies Cell culture Cell division Chromosome Clone Cloning Cord blood stem cells Culture medium Differentiation Directed ... Pluripotent Polar body Preimplantation Proliferation Regenerative medicine Reproductive cloning Signals Somatic cell Somatic cell nuclear transfer (SCNT) ...

  5. Human Renal Normal, Tumoral, and Cancer Stem Cells Express Membrane-Bound Interleukin-15 Isoforms Displaying Different Functions1

    PubMed Central

    Azzi, Sandy; Gallerne, Cindy; Romei, Cristina; Le Coz, Vincent; Gangemi, Rosaria; Khawam, Krystel; Devocelle, Aurore; Gu, Yanhong; Bruno, Stefania; Ferrini, Silvano; Chouaib, Salem; Eid, Pierre; Azzarone, Bruno; Giron-Michel, Julien

    2015-01-01

    Intrarenal interleukin-15 (IL-15) participates to renal pathophysiology, but the role of its different membrane-bound isoforms remains to be elucidated. In this study, we reassess the biology of membrane-bound IL-15 (mb-IL-15) isoforms by comparing primary cultures of human renal proximal tubular epithelial cells (RPTEC) to peritumoral (ptumTEC), tumoral (RCC), and cancer stem cells (CSC/CD105+). RPTEC express a 14 to 16 kDa mb-IL-15, whose existence has been assumed but never formally demonstrated and likely represents the isoform anchored at the cell membrane through the IL-15 receptor α (IL-15Rα) chain, because it is sensitive to acidic treatment and is not competent to deliver a reverse signal. By contrast, ptumTEC, RCC, and CSC express a novel N-hyperglycosylated, short-lived transmembrane mb-IL-15 (tmb-IL-15) isoform around 27 kDa, resistant to acidic shock, delivering a reverse signal in response to its soluble receptor (sIL-15Rα). This reverse signal triggers the down-regulation of the tumor suppressor gene E-cadherin in ptumTEC and RCC but not in CSC/CD105+, where it promotes survival. Indeed, through the AKT pathway, tmb-IL-15 protects CSC/CD105+ from non-programmed cell death induced by serum starvation. Finally, both mb-IL-15 and tmb-IL-15 are sensitive to metalloproteases, and the cleaved tmb-IL-15 (25 kDa) displays a powerful anti-apoptotic effect on human hematopoietic cells. Overall, our data indicate that both mb-IL-15 and tmb-IL-15 isoforms play a complex role in renal pathophysiology downregulating E-cadherin and favoring cell survival. Moreover, “apparently normal” ptumTEC cells, sharing different properties with RCC, could contribute to organize an enlarged peritumoral “preneoplastic” environment committed to favor tumor progression. PMID:26152359

  6. Extinction models for cancer stem cell therapy

    PubMed Central

    Sehl, Mary; Zhou, Hua; Sinsheimer, Janet S.; Lange, Kenneth L.

    2012-01-01

    Cells with stem cell-like properties are now viewed as initiating and sustaining many cancers. This suggests that cancer can be cured by driving these cancer stem cells to extinction. The problem with this strategy is that ordinary stem cells are apt to be killed in the process. This paper sets bounds on the killing differential (difference between death rates of cancer stem cells and normal stem cells) that must exist for the survival of an adequate number of normal stem cells. Our main tools are birth–death Markov chains in continuous time. In this framework, we investigate the extinction times of cancer stem cells and normal stem cells. Application of extreme value theory from mathematical statistics yields an accurate asymptotic distribution and corresponding moments for both extinction times. We compare these distributions for the two cell populations as a function of the killing rates. Perhaps a more telling comparison involves the number of normal stem cells NH at the extinction time of the cancer stem cells. Conditioning on the asymptotic time to extinction of the cancer stem cells allows us to calculate the asymptotic mean and variance of NH. The full distribution of NH can be retrieved by the finite Fourier transform and, in some parameter regimes, by an eigenfunction expansion. Finally, we discuss the impact of quiescence (the resting state) on stem cell dynamics. Quiescence can act as a sanctuary for cancer stem cells and imperils the proposed therapy. We approach the complication of quiescence via multitype branching process models and stochastic simulation. Improvements to the τ-leaping method of stochastic simulation make it a versatile tool in this context. We conclude that the proposed therapy must target quiescent cancer stem cells as well as actively dividing cancer stem cells. The current cancer models demonstrate the virtue of attacking the same quantitative questions from a variety of modeling, mathematical, and computational perspectives

  7. Microbioreactors for Stem Cell Research

    NASA Astrophysics Data System (ADS)

    Freytes, Donald O.; Vunjak-Novakovic, Gordana

    During tissue development and regeneration, stem cells respond to the entire milieu of their environment, through dynamic interactions with the surrounding cells, extracellular matrix, and cascades of molecular and physical regulatory factors. A new generation of culture systems is emerging to offer some of the biological fidelity of a whole organism within highly controllable in vitro settings and provide the cultured cells with the combinations of factors they normally encounter in vivo. There is a growing notion that such "biomimetic" systems are essential for unlocking the full potential of stem cells - for tissue regeneration as well as biological research. In this chapter, we discuss the biological principles for designing biologically inspired culture systems for stem cell research and focus on the control of stem cell microenvironment through surface patterning, microfluidics, and electrical stimulation.

  8. Keratinocyte stem cells: a commentary.

    PubMed

    Potten, Christopher S; Booth, Catherine

    2002-10-01

    For many years it has been widely accepted that stem cells play a crucial role in adult tissue maintenance. The concept that the renewing tissues of the body contain a small subcompartment of self-maintaining stem cells, upon which the entire tissue is dependent, is also now accepted as applicable to all renewing tissues. Gene therapy and tissue engineering are driving considerable interest in the clinical application of such hierarchically organized cellular compartments. Recent initial observations have provided a tantalizing insight into the large pluripotency of these cells. Indeed, scientists are now beginning to talk about the possible totipotency of some adult tissue stem cells. Such work is currently phenomenologic, but analysis of data derived from genomics and proteomics, identifying the crucial control signals involved, will soon provide a further impetus to stem cell biology with far reaching applications. The epidermis with its relatively simple structure, ease of accessibility, and the ability to grow its cells in vitro is one obvious target tissue for testing stem cell manipulation theories. It is crucial, however, that the normal keratinocyte stem cell is thoroughly characterized prior to attempting to manipulate its pluripotency. This commentary assesses the data generated to date and critically discusses the conclusions that have been drawn. Our current level of understanding, or lack of understanding, of the keratinocyte stem cell is reviewed.

  9. MicroRNA-17 promotes normal ovarian cancer cells to cancer stem cells development via suppression of the LKB1-p53-p21/WAF1 pathway.

    PubMed

    Liu, Te; Qin, Wenxing; Hou, Lengchen; Huang, Yongyi

    2015-03-01

    The mechanism underlying the development of human ovarian cancer is poorly understood. The liver kinase protein, LKB1, is hypothesized to play a pivotal role in tumor cell proliferation and invasion capacity through regulation of p53 and p21/WAF1 expression. Previous studies suggest LKB1 may, in turn, be regulated by microRNA-17. Here, we examined the role of miR-17 in the expression of LKB1 and the downstream effects on proliferation and invasion capacity of normal ovarian cancer cells (OCCs) and ovarian stem cells. In this study, both the mRNA and protein expression levels of LKB1, p53, and p21 decreased in OCCs following transfection with a miR-17 expression plasmid. MiR-17 expression affected cell cycle regulation and stimulated the proliferation and invasion capacity of OCCs in vitro. ChIP assays indicated that the binding efficiency of p53 to the p21/WAF1 gene promoter was much lower in miR-17 transfected OCCs than in OCCs transfected with a mutated miR-17. Co-immunoprecipitation and western blotting showed significantly lower levels of p53 and p53 Ser15-pho in the miR-17 transfected OCCs as compared to the mutant miR-17 transfected OCCs. Xenograft experiments confirmed that suppression of tumor growth in vivo occurred in the absence of functional miR-17. These findings suggest that mature miR-17 expression may have an important role in the pathogenesis of human ovarian tumors through its interference with the LKB1-p53-p21/WAF1 pathway expression by epigenetic modification. These findings are of potential importance in the identification of novel therapeutic targets in human ovarian cancer.

  10. Stem cells and reproduction

    PubMed Central

    Du, Hongling; Taylor, Hugh S.

    2011-01-01

    Purpose of review To review the latest developments in reproductive tract stem cell biology. Recent findings In 2004, two studies indicated that ovaries contain stem cells which form oocytes in adults and that can be cultured in vitro into mature oocytes. A live birth after orthotopic transplantation of cyropreserved ovarian tissue in a woman whose ovaries were damaged by chemotherapy demonstrates the clinical potential of these cells. In the same year, another study provided novel evidence of endometrial regeneration by stem cells in women who received bone marrow transplants. This finding has potential for the use in treatment of uterine disorders. It also supports a new theory for the cause of endometriosis, which may have its origin in ectopic transdifferentiation of stem cells. Several recent studies have demonstrated that fetal cells enter the maternal circulation and generate microchimerism in the mother. The uterus is a dynamic organ permeable to fetal stem cells, capable of transdifferentiation and an end organ in which bone marrow stem cells may differentiate. Finally stem cell transformation can be an underlying cause of ovarian cancer. Summary Whereas we are just beginning to understand stem cells, the potential implications of stem cells to reproductive biology and medicine are apparent. PMID:20305558

  11. Stem cells in urology.

    PubMed

    Aboushwareb, Tamer; Atala, Anthony

    2008-11-01

    The shortage of donors for organ transplantation has stimulated research on stem cells as a potential resource for cell-based therapy in all human tissues. Stem cells have been used for regenerative medicine applications in many organ systems, including the genitourinary system. The potential applications for stem cell therapy have, however, been restricted by the ethical issues associated with embryonic stem cell research. Instead, scientists have explored other cell sources, including progenitor and stem cells derived from adult tissues and stem cells derived from the amniotic fluid and placenta. In addition, novel techniques for generating stem cells in the laboratory are being developed. These techniques include somatic cell nuclear transfer, in which the nucleus of an adult somatic cell is placed into an oocyte, and reprogramming of adult cells to induce stem-cell-like behavior. Such techniques are now being used in tissue engineering applications, and some of the most successful experiments have been in the field of urology. Techniques to regenerate bladder tissue have reached the clinic, and exciting progress is being made in other areas, such as regeneration of the kidney and urethra. Cell therapy as a treatment for incontinence and infertility might soon become a reality. Physicians should be optimistic that regenerative medicine and tissue engineering will one day provide mainstream treatment options for urologic disorders.

  12. NAC1, a potential stem cell pluripotency factor expression in normal endometrium, endometrial hyperplasia and endometrial carcinoma.

    PubMed

    Ishikawa, Masako; Nakayama, Kentaro; Yeasmin, Shamima; Katagiri, Atsuko; Iida, Kouji; Nakayama, Naomi; Miyazaki, Kohji

    2010-05-01

    The purpose of this study was to investigate the role of NAC1 in the development of endometrial cancer. NAC1 expression and localization were assessed with immunohistochemistry in the normal cyclic human endometrium, hyperplastic endometrium, and endometrial cancer. Expression of NAC1 in the glandular cells was significantly higher in the early and mid proliferative phases than in the other menstrual phases, endometrial hyperplasia, and endometrial carcinoma. NAC1 expression was down-regulated during endometrial carcinogenesis. There were significant correlations between positive NAC1 expression and pathological grade (P=0.037). No significant associations were found between NAC1 expression and the other clinicopathological characteristics including patient age, FIGO staging, depth of myometrial invasion, pelvic lymph node metastasis, lymphovascular space invasion, menopause, or body mass index. NAC1 gene knockdown inhibited cell growth and induced apoptosis in Ishikawa, HHUA, and JHEM2 cell lines, all of which overexpressed NAC1. Ectopic overexpression of the NAC1 gene stimulated cell proliferation in the HEC1B, and JHEM1 endometrial cancer cell lines, which have lower endogenous NAC1 expression. Endometrial carcinomas with NAC1 overexpression are clinically aggressive, high-grade carcinomas. Therefore, detection of NAC1 overexpression in endometrial cancers may identify patients who will benefit from NAC1 targeted therapy.

  13. Senescence-Associated Molecular and Epigenetic Alterations in Mesenchymal Stem Cell Cultures from Amniotic Fluid of Normal and Fetus-Affected Pregnancy

    PubMed Central

    Savickienė, Jūratė; Baronaitė, Sandra; Zentelytė, Aistė; Treigytė, Gražina

    2016-01-01

    Human amniotic-fluid-derived mesenchymal stem cells (AF-MSCs) are interesting for their multilineage differentiation potential and wide range of therapeutic applications due to the ease of culture expansion. However, MSCs undergo replicative senescence. So far, the molecular mechanisms that underlie fetal diseases and cell senescence are still poorly understood. Here, we analyzed senescence-associated morphologic, molecular, and epigenetic characteristics during propagation of MSCs derived from AF of normal and fetus-affected pregnancy. AF-MSCs cultures from both cell sources displayed quite similar morphology and expression of specific cell surface (CD44, CD90, and CD105) and stemness (Oct4, Nanog, Sox2, and Rex1) markers but had interindividual variability in proliferation capability and time to reach senescence. Within passages 4 and 8, senescent cultures exhibited typical morphological features, senescence-associated β-galactosidase activity, increased levels of p16, and decreased levels of miR-17 and miR-21 but showed differential expression of p21, p53, and ATM dependently on the onset of cell senescence. These differences correlated with changes in the level of chromatin modifiers (DNMT1 and HDAC1) and polycomb group proteins (EZH2, SUZ12, and BMI1) paralleling with changes in the expression of repressive histone marks (H3K9me3 and H3K27me3) and stemness markers (Oct4, Nanog, Sox2, and Rex1). Therefore epigenetic factors are important for AF-MSCs senescence process that may be related with individuality of donor or a fetus malignancy status. PMID:27803714

  14. Targeting Breast Cancer Stem Cells

    PubMed Central

    McDermott, Sean P.; Wicha, Max S.

    2010-01-01

    The cancer stem cell (CSC) hypothesis postulates that tumors are maintained by a self-renewing CSC population that is also capable of differentiating into non-self renewing cell populations that constitute the bulk of the tumor. Although, the CSC hypothesis does not directly address the cell of origin of cancer, it is postulated that tissue-resident stem or progenitors are the most common targets of transformation. Clinically, CSCs are predicted to mediate tumor recurrence after chemo- and radiation-therapy due to the relative inability of these modalities to effectively target CSCs. If this is the case, then CSC must be efficiently targeted to achieve a true cure. Similarities between normal and malignant stem cells, at the levels of cell-surface proteins, molecular pathways, cell cycle quiescence, and microRNA signaling present challenges in developing CSC-specific therapeutics. Approaches to targeting CSCs include the development of agents targeting known stem cell regulatory pathways as well as unbiased high-throughput siRNA or small-molecule screening. Based on studies of pathways present in normal stem cells, recent work has identified potential “Achilles heals” of CSC, whereas unbiased screening provides opportunities to identify new pathways utilized by CSC as well as develop potential therapeutic agents. Here, we review both approaches and their potential to effectively target breast CSC. PMID:20599450

  15. Intraoperative Stem Cell Therapy

    PubMed Central

    Coelho, Mónica Beato; Cabral, Joaquim M.S.; Karp, Jeffrey M.

    2013-01-01

    Stem cells hold significant promise for regeneration of tissue defects and disease-modifying therapies. Although numerous promising stem cell approaches are advancing in clinical trials, intraoperative stem cell therapies offer more immediate hope by integrating an autologous cell source with a well-established surgical intervention in a single procedure. Herein, the major developments in intraoperative stem cell approaches, from in vivo models to clinical studies, are reviewed, and the potential regenerative mechanisms and the roles of different cell populations in the regeneration process are discussed. Although intraoperative stem cell therapies have been shown to be safe and effective for several indications, there are still critical challenges to be tackled prior to adoption into the standard surgical armamentarium. PMID:22809140

  16. Stem Cells and Liver Regeneration

    PubMed Central

    DUNCAN, ANDREW W.; DORRELL, CRAIG; GROMPE, MARKUS

    2011-01-01

    One of the defining features of the liver is the capacity to maintain a constant size despite injury. Although the precise molecular signals involved in the maintenance of liver size are not completely known, it is clear that the liver delicately balances regeneration with overgrowth. Mammals, for example, can survive surgical removal of up to 75% of the total liver mass. Within 1 week after liver resection, the total number of liver cells is restored. Moreover, liver overgrowth can be induced by a variety of signals, including hepatocyte growth factor or peroxisome proliferators; the liver quickly returns to its normal size when the proliferative signal is removed. The extent to which liver stem cells mediate liver regeneration has been hotly debated. One of the primary reasons for this controversy is the use of multiple definitions for the hepatic stem cell. Definitions for the liver stem cell include the following: (1) cells responsible for normal tissue turnover, (2) cells that give rise to regeneration after partial hepatectomy, (3) cells responsible for progenitor-dependent regeneration, (4) cells that produce hepatocyte and bile duct epithelial phenotypes in vitro, and (5) transplantable liver-repopulating cells. This review will consider liver stem cells in the context of each definition. PMID:19470389

  17. Fish stem cell cultures.

    PubMed

    Hong, Ni; Li, Zhendong; Hong, Yunhan

    2011-04-13

    Stem cells have the potential for self-renewal and differentiation. First stem cell cultures were derived 30 years ago from early developing mouse embryos. These are pluripotent embryonic stem (ES) cells. Efforts towards ES cell derivation have been attempted in other mammalian and non-mammalian species. Work with stem cell culture in fish started 20 years ago. Laboratory fish species, in particular zebrafish and medaka, have been the focus of research towards stem cell cultures. Medaka is the second organism that generated ES cells and the first that gave rise to a spermatogonial stem cell line capable of test-tube sperm production. Most recently, the first haploid stem cells capable of producing whole animals have also been generated from medaka. ES-like cells have been reported also in zebrafish and several marine species. Attempts for germline transmission of ES cell cultures and gene targeting have been reported in zebrafish. Recent years have witnessed the progress in markers and procedures for ES cell characterization. These include the identification of fish homologs/paralogs of mammalian pluripotency genes and parameters for optimal chimera formation. In addition, fish germ cell cultures and transplantation have attracted considerable interest for germline transmission and surrogate production. Haploid ES cell nuclear transfer has proven in medaka the feasibility of semi-cloning as a novel assisted reproductive technology. In this special issue on "Fish Stem Cells and Nuclear Transfer", we will focus our review on medaka to illustrate the current status and perspective of fish stem cells in research and application. We will also mention semi-cloning as a new development to conventional nuclear transfer.

  18. Stem cells in dermatology.

    PubMed

    Ogliari, Karolyn Sassi; Marinowic, Daniel; Brum, Dario Eduardo; Loth, Fabrizio

    2014-01-01

    Preclinical and clinical research have shown that stem cell therapy could be a promising therapeutic option for many diseases in which current medical treatments do not achieve satisfying results or cure. This article describes stem cells sources and their therapeutic applications in dermatology today.

  19. Stem Cell Transplants (For Teens)

    MedlinePlus

    ... How Can I Help a Friend Who Cuts? Stem Cell Transplants KidsHealth > For Teens > Stem Cell Transplants Print ... Does it Take to Recover? Coping What Are Stem Cells? As you probably remember from biology class, every ...

  20. Stem cells and repair of lung injuries

    PubMed Central

    Neuringer, Isabel P; Randell, Scott H

    2004-01-01

    Fueled by the promise of regenerative medicine, currently there is unprecedented interest in stem cells. Furthermore, there have been revolutionary, but somewhat controversial, advances in our understanding of stem cell biology. Stem cells likely play key roles in the repair of diverse lung injuries. However, due to very low rates of cellular proliferation in vivo in the normal steady state, cellular and architectural complexity of the respiratory tract, and the lack of an intensive research effort, lung stem cells remain poorly understood compared to those in other major organ systems. In the present review, we concisely explore the conceptual framework of stem cell biology and recent advances pertinent to the lungs. We illustrate lung diseases in which manipulation of stem cells may be physiologically significant and highlight the challenges facing stem cell-related therapy in the lung. PMID:15285789

  1. [Therapeutic use of stem cells. II. Adult stem cells].

    PubMed

    Uzan, Georges

    2004-09-30

    Many degenerative diseases are not curable by means of classical medicine. The long term objective of cell therapy is to treat the patients with their own stem cells that could be either purified from the diseased organ or from "reservoirs" of stem cells such as that constituted by the bone marrow. The existence of stem cells in the organs or reservoirs is now established in vitro and in some cases, in animal models. Numbers of technical problems linked to the scarcity of these cells still delay the clinical use of purified stem cells. However, clinical protocols using heterogeneous cell populations have already started to treat a growing number of diseases. In some case, autologous cells can be used, as it is the case for bone marrow transplantation in blood diseases. Mesenchymal cells, also purified from the bone marrow are currently used in orthopaedic diseases. Because these cells reveal a broad differentiation potential, active research programs explore their possible use for treatment of other diseases. Bone marrow also contains vascular stem cells that could be active in reappearing defective vessels responsible for ischaemic diseases. Indeed, clinical trials in which bone marrow cells are injected in the cardiac muscle of patients with myocardial infarction or in the leg muscle (gastrocnemius) of patients with hind limb ischaemia have already started. Artificial skin prepared from skin biopsies is used for the reconstitution of the derma of severely burned patients. Clinical trials have also started, using allogenic cells. The patients must be treated by immunosuppressive drugs. Neurodegenerative diseases such as Parkinson have been successfully treated by intra-cerebral injection of foetal neurones. Pancreatic islets implanted in the liver have shown to re-establish a normal glycaemia in diabetic patients. However, all these clinical trials use differentiated cells or at least progenitors which display differentiation potential and lifetime much more

  2. Human dermal stem/progenitor cell-derived conditioned medium ameliorates ultraviolet a-induced damage of normal human dermal fibroblasts.

    PubMed

    Shim, Joong Hyun; Park, Ju-Yearl; Lee, Mi-Gi; Kang, Hak Hee; Lee, Tae Ryong; Shin, Dong Wook

    2013-01-01

    Adult skin stem cells are considered an attractive cell resource for therapeutic potential in aged skin. We previously reported that multipotent human dermal stem/progenitor cells (hDSPCs) can be enriched from (normal human dermal fibroblasts (NHDFs) using collagen type IV. However, the beneficial effects of hDSPCs on aged skin remain to be elucidated. In the present study, we analyzed the growth factors secreted from hDSPCs in conditioned medium (CM) derived from hDSPCs (hDSPC-CM) and found that hDSPCs secreted higher levels of bFGF, IGFBP-1, IGFBP-2, HGF, VEGF and IGF-1 compared with non-hDSPCs. We then investigated whether hDSPC-CM has an effect on ultraviolet A (UVA)-irradiated NHDFs. Real-time RT-PCR analysis revealed that the treatment of UVA-irradiated NHDFs with hDSPC-CM significantly antagonized the UVA-induced up-regulation of the MMP1 and the UVA-induced down-regulation of the collagen types I, IV and V and TIMP1 mRNA expressions. Furthermore, a scratch wound healing assay showed that hDSPC-CM enhanced the migratory properties of UVA-irradiated NHDFs. hDSPC-CM also significantly reduced the number of the early and late apoptotic cell population in UVA-irradiated NHDFs. Taken together, these data suggest that hDSPC-CM can exert some beneficial effects on aged skin and may be used as a therapeutic agent to improve skin regeneration and wound healing.

  3. Expression of proteolipid protein gene in spinal cord stem cells and early oligodendrocyte progenitor cells is dispensable for normal cell migration and myelination.

    PubMed

    Harlow, Danielle E; Saul, Katherine E; Culp, Cecilia M; Vesely, Elisa M; Macklin, Wendy B

    2014-01-22

    Plp1 gene expression occurs very early in development, well before the onset of myelination, creating a conundrum with regard to the function of myelin proteolipid protein (PLP), one of the major proteins in compact myelin. Using PLP-EGFP mice to investigate Plp1 promoter activity, we found that, at very early time points, PLP-EGFP was expressed in Sox2+ undifferentiated precursors in the spinal cord ventricular zone (VZ), as well as in the progenitors of both neuronal and glial lineages. As development progressed, most PLP-EGFP-expressing cells gave rise to oligodendrocyte progenitor cells (OPCs). The expression of PLP-EGFP in the spinal cord was quite dynamic during development. PLP-EGFP was highly expressed as cells delaminated from the VZ. Expression was downregulated as cells moved laterally through the cord, and then robustly upregulated as OPCs differentiated into mature myelinating oligodendrocytes. The presence of PLP-EGFP expression in OPCs raises the question of its role in this migratory population. We crossed PLP-EGFP reporter mice into a Plp1-null background to investigate the role of PLP in early OPC development. In the absence of PLP, normal numbers of OPCs were generated and their distribution throughout the spinal cord was unaffected. However, the orientation and length of OPC processes during migration was abnormal in Plp1-null mice, suggesting that PLP plays a role either in the structural integrity of OPC processes or in their response to extracellular cues that orient process outgrowth.

  4. Normal Untreated Jurkat Cells

    NASA Technical Reports Server (NTRS)

    2004-01-01

    Biomedical research offers hope for a variety of medical problems, from diabetes to the replacement of damaged bone and tissues. Bioreactors, which are used to grow cells and tissue cultures, play a major role in such research and production efforts. The objective of the research was to define a way to differentiate between effects due to microgravity and those due to possible stress from non-optimal spaceflight conditions. These Jurkat cells, a human acute T-cell leukemia was obtained to evaluate three types of potential experimental stressors: a) Temperature elevation; b) Serum starvation; and c) Centrifugal force. The data from previous spaceflight experiments showed that actin filaments and cell shape are significantly different for the control. These normal cells serve as the baseline for future spaceflight experiments.

  5. SMOOTH MUSCLE STEM CELLS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Vascular smooth muscle cells (SMCs) originate from multiple types of progenitor cells. In the embryo, the most well-studied SMC progenitor is the cardiac neural crest stem cell. Smooth muscle differentiation in the neural crest lineage is controlled by a combination of cell intrinsic factors, includ...

  6. Stem cell plasticity in development and cancer: epigenetic origin of cancer stem cells.

    PubMed

    Shah, Mansi; Allegrucci, Cinzia

    2013-01-01

    Stem cells are unique cells that can self-renew and differentiate into many cell types. Plasticity is a fundamental characteristic of stem cells and it is regulated by reversible epigenetic modifications. Although gene-restriction programs are established during embryonic development when cell lineages are formed, stem cells retain a degree of flexibility that is essential for tissue regeneration. For instance, quiescent adult stem cells can be induced to proliferate and trans-differentiate in response to injury. The same degree of plasticity is observed in cancer, where cancer cells with stem cell characteristics (or cancer stem cells) are formed by transformation of normal stem cells or de-differentiation of somatic cells. Reprogramming experiments with normal somatic cells and cancer cells show that epigenetic landscapes are more plastic than originally thought and that their manipulation can induce changes in cell fate. Our knowledge of stem cell function is still limited and only by understanding the mechanisms regulating developmental potential together with the definition of epigenetic maps of normal and diseased tissues we can reveal the true extent of their plasticity. In return, the control of plastic epigenetic programs in stem cells will allow us to develop effective treatments for degenerative diseases and cancer. PMID:23150267

  7. Plant Stem Cells.

    PubMed

    Greb, Thomas; Lohmann, Jan U

    2016-09-12

    Among the trending topics in the life sciences, stem cells have received a fair share of attention in the public debate - mostly in connection with their potential for biomedical application and therapies. While the promise of organ regeneration and the end of cancer have captured our imagination, it has gone almost unnoticed that plant stem cells represent the ultimate origin of much of the food we eat, the oxygen we breathe, as well the fuels we burn. Thus, plant stem cells may be ranked among the most important cells for human well-being. Research by many labs in the last decades has uncovered a set of independent stem cell systems that fulfill the specialized needs of plant development and growth in four dimensions. Surprisingly, the cellular and molecular design of these systems is remarkably similar, even across diverse species. In some long-lived plants, such as trees, plant stem cells remain active over hundreds or even thousands of years, revealing the exquisite precision in the underlying control of proliferation, self-renewal and differentiation. In this minireview, we introduce the basic features of the three major plant stem cell systems building on these facts, highlight their modular design at the level of cellular layout and regulatory underpinnings and briefly compare them with their animal counterparts. PMID:27623267

  8. The biology of cancer stem cells.

    PubMed

    Lobo, Neethan A; Shimono, Yohei; Qian, Dalong; Clarke, Michael F

    2007-01-01

    Cancers originally develop from normal cells that gain the ability to proliferate aberrantly and eventually turn malignant. These cancerous cells then grow clonally into tumors and eventually have the potential to metastasize. A central question in cancer biology is, which cells can be transformed to form tumors? Recent studies elucidated the presence of cancer stem cells that have the exclusive ability to regenerate tumors. These cancer stem cells share many characteristics with normal stem cells, including self-renewal and differentiation. With the growing evidence that cancer stem cells exist in a wide array of tumors, it is becoming increasingly important to understand the molecular mechanisms that regulate self-renewal and differentiation because corruption of genes involved in these pathways likely participates in tumor growth. This new paradigm of oncogenesis has been validated in a growing list of tumors. Studies of normal and cancer stem cells from the same tissue have shed light on the ontogeny of tumors. That signaling pathways such as Bmi1 and Wnt have similar effects in normal and cancer stem cell self-renewal suggests that common molecular pathways regulate both populations. Understanding the biology of cancer stem cells will contribute to the identification of molecular targets important for future therapies.

  9. [Stem cells and cancer].

    PubMed

    Arvelo, Francisco; Cotte, Carlos; Sojo, Felipe

    2014-12-01

    Surgery, radiotherapy and chemotherapy are universally recognized as the most effective anti-cancer therapies. Despite significant advances directed towards elucidating molecular mechanisms and developing clinical trials, cancer still remains a major public health issue. Cancer stem cells are a subpopulation of the cells that form the tumor. The discovery of these human cancer cells opens a perspective for understanding tumor recurrence, drug resistance and metastasis; and opens up new research directions on how cancer cells are capable of switching from dormancy to malignancy. Therapeutic alternatives emerge from a better understanding of the biology and the environment of tumor stem cells. The present paper aims to summarize the characteristics and properties of cancer stem cells, the ongoing research, as well as the best strategies for prevention and control of the mechanisms of tumor recurrence.

  10. Aneuploidy in stem cells

    PubMed Central

    Garcia-Martinez, Jorge; Bakker, Bjorn; Schukken, Klaske M; Simon, Judith E; Foijer, Floris

    2016-01-01

    Stem cells hold enormous promise for regenerative medicine as well as for engineering of model systems to study diseases and develop new drugs. The discovery of protocols that allow for generating induced pluripotent stem cells (IPSCs) from somatic cells has brought this promise steps closer to reality. However, as somatic cells might have accumulated various chromosomal abnormalities, including aneuploidies throughout their lives, the resulting IPSCs might no longer carry the perfect blueprint for the tissue to be generated, or worse, become at risk of adopting a malignant fate. In this review, we discuss the contribution of aneuploidy to healthy tissues and how aneuploidy can lead to disease. Furthermore, we review the differences between how somatic cells and stem cells respond to aneuploidy. PMID:27354891

  11. Cancer stem cell signaling pathways.

    PubMed

    Matsui, William H

    2016-09-01

    Tissue development and homeostasis are governed by the actions of stem cells. Multipotent cells are capable of self-renewal during the course of one's lifetime. The accurate and appropriate regulation of stem cell functions is absolutely critical for normal biological activity. Several key developmental or signaling pathways have been shown to play essential roles in this regulatory capacity. Specifically, the Janus-activated kinase/signal transducer and activator of transcription, Hedgehog, Wnt, Notch, phosphatidylinositol 3-kinase/phosphatase and tensin homolog, and nuclear factor-κB signaling pathways have all been shown experimentally to mediate various stem cell properties, such as self-renewal, cell fate decisions, survival, proliferation, and differentiation. Unsurprisingly, many of these crucial signaling pathways are dysregulated in cancer. Growing evidence suggests that overactive or abnormal signaling within and among these pathways may contribute to the survival of cancer stem cells (CSCs). CSCs are a relatively rare population of cancer cells capable of self-renewal, differentiation, and generation of serially transplantable heterogeneous tumors of several types of cancer. PMID:27611937

  12. Chondrogenesis of periodontal ligament stem cells by transforming growth factor-β3 and bone morphogenetic protein-6 in a normal healthy impacted third molar.

    PubMed

    Choi, Sunyoung; Cho, Tae-Jun; Kwon, Soon-Keun; Lee, Gene; Cho, Jaejin

    2013-03-01

    The periodontal ligament-derived mesenchymal stem cell is regarded as a source of adult stem cells due to its multipotency. However, the proof of chondrogenic potential of the cells is scarce. Therefore, we investigated the chondrogenic differentiation capacity of periodontal ligament derived mesenchymal stem cells induced by transforming growth factor (TGF)-β3 and bone morphogenetic protein (BMP)-6. After isolation of periodontal ligament stem cells (PDLSCs) from human periodontal ligament, the cells were cultured in Dulbecco's modified Eagle's medium (DMEM) with 20% fetal bovine serum (FBS). A mechanical force initiated chondrogenic differentiation of the cells. For chondrogenic differentiation, 10 µg·L⁻¹ TGF-β3 or 100 µg∙L⁻¹ BMP-6 and the combination treating group for synergistic effect of the growth factors. We analyzed the PDLSCs by fluorescence-activated cell sorting and chondrogenesis were evaluated by glycosaminoglycans assay, histology, immunohistochemistry and genetic analysis. PDLSCs showed mesenchymal stem cell properties proved by FACS analysis. Glycosaminoglycans contents were increased 217% by TGF-β3 and 220% by BMP-6. The synergetic effect of TGF-β3 and BMP-6 were shown up to 281% compared to control. The combination treatment increased Sox9, aggrecan and collagen II expression compared with not only controls, but also TGF-β3 or BMP-6 single treatment dramatically. The histological analysis also indicated the chondrogenic differentiation of PDLSCs in our conditions. The results of the present study demonstrate the potential of the dental stem cell as a valuable cell source for chondrogenesis, which may be applicable for regeneration of cartilage and bone fracture in the field of cell therapy.

  13. PEDF & stem cells: niche vs. nurture.

    PubMed

    Fitchev, Philip; Chung, Chuhan; Plunkett, Beth A; Brendler, Charles B; Crawford, Susan E

    2014-01-01

    Anti-angiogenic pigment epithelium-derived factor (PEDF) is a multifunctional 50kD secreted glycoprotein emerging as a key factor in stem cell renewal. Characteristics of the stem cell niche can be highly dependent on location, access to the vasculature, oxygen tension and neighboring cells. In the neural stem cell (NSC) niche, specifically the subventricular zone, PEDF actively participates in the self renewal process and promotes stemness by upregulating Notch signaling effectors Hes1 and Hes5. The local vascular endothelial cells and ependymal cells are the likely sources of PEDF for the NSC while mesenchymal and retinal stem cells can actually produce PEDF. The opposing actions of PEDF and VEGF on various cells are recapitulated in the NSC niche. Intraventricular injection of PEDF promotes stem cell renewal, while injection of VEGF prompts differentiation and neurogenesis in the subventricular zone. Enhancing the expression of PEDF in stem cells has promising therapeutic implications. Bone marrow mesenchymal stem cells overexpressing PEDF effectively inhibited pathologic angiogenesis in the murine eye and these same cells suppressed hepatocellular carcinoma growth. As a protein with bioactivities in nearly all normal organ systems, it is likely that PEDF will continue to gain visibility as an essential component in the development and delivery of novel stem cell-based therapies to combat disease.

  14. Dental pulp stem cells

    PubMed Central

    Ashri, Nahid Y.; Ajlan, Sumaiah A.; Aldahmash, Abdullah M.

    2015-01-01

    Inflammatory periodontal disease is a major cause of loss of tooth-supporting structures. Novel approaches for regeneration of periodontal apparatus is an area of intensive research. Periodontal tissue engineering implies the use of appropriate regenerative cells, delivered through a suitable scaffold, and guided through signaling molecules. Dental pulp stem cells have been used in an increasing number of studies in dental tissue engineering. Those cells show mesenchymal (stromal) stem cell-like properties including self-renewal and multilineage differentiation potentials, aside from their relative accessibility and pleasant handling properties. The purpose of this article is to review the biological principles of periodontal tissue engineering, along with the challenges facing the development of a consistent and clinically relevant tissue regeneration platform. This article includes an updated review on dental pulp stem cells and their applications in periodontal regeneration, in combination with different scaffolds and growth factors. PMID:26620980

  15. Stem cells in microfluidics

    PubMed Central

    Wu, Huei-Wen; Lin, Chun-Che; Lee, Gwo-Bin

    2011-01-01

    Microfluidic techniques have been recently developed for cell-based assays. In microfluidic systems, the objective is for these microenvironments to mimic in vivo surroundings. With advantageous characteristics such as optical transparency and the capability for automating protocols, different types of cells can be cultured, screened, and monitored in real time to systematically investigate their morphology and functions under well-controlled microenvironments in response to various stimuli. Recently, the study of stem cells using microfluidic platforms has attracted considerable interest. Even though stem cells have been studied extensively using bench-top systems, an understanding of their behavior in in vivo-like microenvironments which stimulate cell proliferation and differentiation is still lacking. In this paper, recent cell studies using microfluidic systems are first introduced. The various miniature systems for cell culture, sorting and isolation, and stimulation are then systematically reviewed. The main focus of this review is on papers published in recent years studying stem cells by using microfluidic technology. This review aims to provide experts in microfluidics an overview of various microfluidic systems for stem cell research. PMID:21522491

  16. Catalyzing stem cell research.

    PubMed

    Willemse, Lisa; Lyall, Drew; Rudnicki, Michael

    2008-09-01

    In 2001, the Stem Cell Network was the first of its kind, a bold initiative to forge and nurture pan-Canadian collaborations involving researchers, engineers, clinicians and private and public sector partners. Canada's broad and deep pool of stem cell talent proved to be a fertile ground for such an initiative, giving rise to a strong, thriving network that, 7 years later, can list innovative cell expansion and screening technologies, early-phase clinical trials for stroke, pulmonary hypertension, muscular dystrophy and cornea replacement, and leading discourse on ethical, legal and social issues among its accomplishments. As it moves into its second and final phase of funding, the Stem Cell Network continues to push boundaries and has set its sights on overcoming the obstacles that impede the transfer of research findings to clinical applications, commercial products and public policy. PMID:18729799

  17. Catalyzing stem cell research.

    PubMed

    Willemse, Lisa; Lyall, Drew; Rudnicki, Michael

    2008-09-01

    In 2001, the Stem Cell Network was the first of its kind, a bold initiative to forge and nurture pan-Canadian collaborations involving researchers, engineers, clinicians and private and public sector partners. Canada's broad and deep pool of stem cell talent proved to be a fertile ground for such an initiative, giving rise to a strong, thriving network that, 7 years later, can list innovative cell expansion and screening technologies, early-phase clinical trials for stroke, pulmonary hypertension, muscular dystrophy and cornea replacement, and leading discourse on ethical, legal and social issues among its accomplishments. As it moves into its second and final phase of funding, the Stem Cell Network continues to push boundaries and has set its sights on overcoming the obstacles that impede the transfer of research findings to clinical applications, commercial products and public policy.

  18. Stacking the DEK: from chromatin topology to cancer stem cells.

    PubMed

    Privette Vinnedge, Lisa M; Kappes, Ferdinand; Nassar, Nicolas; Wells, Susanne I

    2013-01-01

    Stem cells are essential for development and tissue maintenance and display molecular markers and functions distinct from those of differentiated cell types in a given tissue. Malignant cells that exhibit stem cell-like activities have been detected in many types of cancers and have been implicated in cancer recurrence and drug resistance. Normal stem cells and cancer stem cells have striking commonalities, including shared cell surface markers and signal transduction pathways responsible for regulating quiescence vs. proliferation, self-renewal, pluripotency and differentiation. As the search continues for markers that distinguish between stem cells, progenitor cells and cancer stem cells, growing evidence suggests that a unique chromatin-associated protein called DEK may confer stem cell-like qualities. Here, we briefly describe current knowledge regarding stem and progenitor cells. We then focus on new findings that implicate DEK as a regulator of stem and progenitor cell qualities, potentially through its unusual functions in the regulation of local or global chromatin organization.

  19. Chemotherapy targeting cancer stem cells.

    PubMed

    Liu, Haiguang; Lv, Lin; Yang, Kai

    2015-01-01

    Conventional chemotherapy is the main treatment for cancer and benefits patients in the form of decreased relapse and metastasis and longer overall survival. However, as the target therapy drugs and delivery systems are not wholly precise, it also results in quite a few side effects, and is less efficient in many cancers due to the spared cancer stem cells, which are considered the reason for chemotherapy resistance, relapse, and metastasis. Conventional chemotherapy limitations and the cancer stem cell hypothesis inspired our search for a novel chemotherapy targeting cancer stem cells. In this review, we summarize cancer stem cell enrichment methods, the search for new efficient drugs, and the delivery of drugs targeting cancer stem cells. We also discuss cancer stem cell hierarchy complexity and the corresponding combination therapy for both cancer stem and non-stem cells. Learning from cancer stem cells may reveal novel strategies for chemotherapy in the future.

  20. Chemotherapy targeting cancer stem cells

    PubMed Central

    Liu, Haiguang; Lv, Lin; Yang, Kai

    2015-01-01

    Conventional chemotherapy is the main treatment for cancer and benefits patients in the form of decreased relapse and metastasis and longer overall survival. However, as the target therapy drugs and delivery systems are not wholly precise, it also results in quite a few side effects, and is less efficient in many cancers due to the spared cancer stem cells, which are considered the reason for chemotherapy resistance, relapse, and metastasis. Conventional chemotherapy limitations and the cancer stem cell hypothesis inspired our search for a novel chemotherapy targeting cancer stem cells. In this review, we summarize cancer stem cell enrichment methods, the search for new efficient drugs, and the delivery of drugs targeting cancer stem cells. We also discuss cancer stem cell hierarchy complexity and the corresponding combination therapy for both cancer stem and non-stem cells. Learning from cancer stem cells may reveal novel strategies for chemotherapy in the future. PMID:26045975

  1. Clonogenicity: holoclones and meroclones contain stem cells.

    PubMed

    Beaver, Charlotte M; Ahmed, Aamir; Masters, John R

    2014-01-01

    When primary cultures of normal cells are cloned, three types of colony grow, called holoclones, meroclones and paraclones. These colonies are believed to be derived from stem cells, transit-amplifying cells and differentiated cells respectively. More recently, this approach has been extended to cancer cell lines. However, we observed that meroclones from the prostate cancer cell line DU145 produce holoclones, a paradoxical observation as meroclones are thought to be derived from transit-amplifying cells. The purpose of this study was to confirm this observation and determine if both holoclones and meroclones from cancer cell lines contain stem cells. We demonstrated that both holoclones and meroclones can be serially passaged indefinitely, are highly proliferative, can self-renew to form spheres, are serially tumorigenic and express stem cell markers. This study demonstrates that the major difference between holoclones and meroclones derived from a cancer cell line is the proportion of stem cells within each colony, not the presence or absence of stem cells. These findings may reflect the properties of cancer as opposed to normal cells, perhaps indicating that the hierarchy of stem cells is more extensive in cancer.

  2. Stem cells and transplant arteriosclerosis.

    PubMed

    Xu, Qingbo

    2008-05-01

    Stem cells can differentiate into a variety of cells to replace dead cells or to repair damaged tissues. Recent evidence indicates that stem cells are involved in the pathogenesis of transplant arteriosclerosis, an alloimmune initiated vascular stenosis that often results in transplant organ failure. Although the pathogenesis of transplant arteriosclerosis is not yet fully understood, recent developments in stem cell research have suggested novel mechanisms of vascular remodeling in allografts. For example, stem cells derived from the recipient may repair damaged endothelial cells of arteries in transplant organs. Further evidence suggests that stem cells or endothelial progenitor cells may be released from both bone marrow and non-bone marrow tissues. Vascular stem cells appear to replenish cells that died in donor vessels. Concomitantly, stem/progenitor cells may also accumulate in the intima, where they differentiate into smooth muscle cells. However, several issues concerning the contribution of stem cells to the pathogenesis of transplant arteriosclerosis are controversial, eg, whether bone marrow-derived stem cells can differentiate into smooth muscle cells that form neointimal lesions of the vessel wall. This review summarizes recent research on the role of stem cells in transplant arteriosclerosis, discusses the mechanisms of stem cell homing and differentiation into mature endothelial and smooth muscle cells, and highlights the controversial issues in the field.

  3. In search of liver cancer stem cells.

    PubMed

    Ma, Stephanie; Chan, Kwok Wah; Guan, Xin-Yuan

    2008-09-01

    Recent research efforts in stem cell and cancer biology have put forth a "stem cell model of carcinogenesis" which stipulates that the capability to maintain tumor formation and growth specifically resides in a small population of cells called cancer stem cells. The stem cell-like characteristics of these cells, including their ability to self-renew and differentiate; and their limited number within the bulk of the tumor mass, are believed to account for their capability to escape conventional therapies. In the past few years, the hypothesis of stem cell-driven tumorigenesis in liver cancer has received substantial support from the recent ability to identify and isolate a subpopulation of liver cancer cells that is not only able to initiate tumor growth, but also serially establish themselves as tumor xenografts with high efficiency and consistency. In this review, stem cell biology that contributes to explain tumor development in the particular context of liver cancer will be discussed. We will begin by briefly considering the knowledge available on normal liver stem cells and their role in tissue renewal and regeneration. We will then summarize the current scientific knowledge of liver cancer stem cells, discuss their relevance to the diagnosis and treatment of the disease and consider the outstanding challenges and potential opportunities that lie ahead of us.

  4. The Seckel syndrome and centrosomal protein Ninein localizes asymmetrically to stem cell centrosomes but is not required for normal development, behavior, or DNA damage response in Drosophila

    PubMed Central

    Zheng, Yiming; Mennella, Vito; Marks, Steven; Wildonger, Jill; Elnagdi, Esraa; Agard, David; Megraw, Timothy L.

    2016-01-01

    Ninein (Nin) is a centrosomal protein whose gene is mutated in Seckel syndrome (SCKL, MIM 210600), an inherited recessive disease that results in primordial dwarfism, cognitive deficiencies, and increased sensitivity to genotoxic stress. Nin regulates neural stem cell self-renewal, interkinetic nuclear migration, and microtubule assembly in mammals. Nin is evolutionarily conserved, yet its role in cell division and development has not been investigated in a model organism. Here we characterize the single Nin orthologue in Drosophila. Drosophila Nin localizes to the periphery of the centrosome but not at centriolar structures as in mammals. However, Nin shares the property of its mammalian orthologue of promoting microtubule assembly. In neural and germline stem cells, Nin localizes asymmetrically to the younger (daughter) centrosome, yet it is not required for the asymmetric division of stem cells. In wing epithelia and muscle, Nin localizes to noncentrosomal microtubule-organizing centers. Surprisingly, loss of nin expression from a nin mutant does not significantly affect embryonic and brain development, fertility, or locomotor performance of mutant flies or their survival upon exposure to DNA-damaging agents. Although it is not essential, our data suggest that Nin plays a supportive role in centrosomal and extracentrosomal microtubule organization and asymmetric stem cell division. PMID:27053665

  5. The Seckel syndrome and centrosomal protein Ninein localizes asymmetrically to stem cell centrosomes but is not required for normal development, behavior, or DNA damage response in Drosophila.

    PubMed

    Zheng, Yiming; Mennella, Vito; Marks, Steven; Wildonger, Jill; Elnagdi, Esraa; Agard, David; Megraw, Timothy L

    2016-06-01

    Ninein (Nin) is a centrosomal protein whose gene is mutated in Seckel syndrome (SCKL, MIM 210600), an inherited recessive disease that results in primordial dwarfism, cognitive deficiencies, and increased sensitivity to genotoxic stress. Nin regulates neural stem cell self-renewal, interkinetic nuclear migration, and microtubule assembly in mammals. Nin is evolutionarily conserved, yet its role in cell division and development has not been investigated in a model organism. Here we characterize the single Nin orthologue in Drosophila Drosophila Nin localizes to the periphery of the centrosome but not at centriolar structures as in mammals. However, Nin shares the property of its mammalian orthologue of promoting microtubule assembly. In neural and germline stem cells, Nin localizes asymmetrically to the younger (daughter) centrosome, yet it is not required for the asymmetric division of stem cells. In wing epithelia and muscle, Nin localizes to noncentrosomal microtubule-organizing centers. Surprisingly, loss of nin expression from a nin mutant does not significantly affect embryonic and brain development, fertility, or locomotor performance of mutant flies or their survival upon exposure to DNA-damaging agents. Although it is not essential, our data suggest that Nin plays a supportive role in centrosomal and extracentrosomal microtubule organization and asymmetric stem cell division. PMID:27053665

  6. Amnion-derived stem cells: in quest of clinical applications.

    PubMed

    Miki, Toshio

    2011-05-19

    In the promising field of regenerative medicine, human perinatal stem cells are of great interest as potential stem cells with clinical applications. Perinatal stem cells could be isolated from normally discarded human placentae, which are an ideal cell source in terms of availability, the fewer number of ethical concerns, less DNA damage, and so on. Numerous studies have demonstrated that some of the placenta-derived cells possess stem cell characteristics like pluripotent differentiation ability, particularly in amniotic epithelial (AE) cells. Term human amniotic epithelium contains a relatively large number of stem cell marker-positive cells as an adult stem cell source. In this review, we introduce a model theory of why so many AE cells possess stem cell characteristics. We also describe previous work concerning the therapeutic applications and discuss the pluripotency of the AE cells and potential pitfalls for amnion-derived stem cell research.

  7. Stem Cells in Mammalian Gonads.

    PubMed

    Wu, Ji; Ding, Xinbao; Wang, Jian

    2016-01-01

    Stem cells have great value in clinical application because of their ability to self-renew and their potential to differentiate into many different cell types. Mammalian gonads, including testes for males and ovaries for females, are composed of germline and somatic cells. In male mammals, spermatogonial stem cells maintain spermatogenesis which occurs continuously in adult testis. Likewise, a growing body of evidence demonstrated that female germline stem cells could be found in mammalian ovaries. Meanwhile, prior studies have shown that somatic stem cells exist in both testes and ovaries. In this chapter, we focus on mammalian gonad stem cells and discuss their characteristics as well as differentiation potentials.

  8. Characterization of amniotic stem cells.

    PubMed

    Koike, Chika; Zhou, Kaixuan; Takeda, Yuji; Fathy, Moustafa; Okabe, Motonori; Yoshida, Toshiko; Nakamura, Yukio; Kato, Yukio; Nikaido, Toshio

    2014-08-01

    The amnion membrane is developed from embryo-derived cells, and amniotic cells have been shown to exhibit multidifferentiation potential. These cells represent a desirable source for stem cells for a variety of reasons. However, to date very few molecular analyses of amnion-derived cells have been reported, and efficient markers for isolating the stem cells remain unclear. This paper assesses the characterization of amnion-derived cells as stem cells by examining stemness marker expressions for amnion-derived epithelial cells and mesenchymal cells by flow cytometry, immunocytochemistry, and quantitative PCR. Flow cytometry revealed that amnion epithelial cells expressed CD133, CD 271, and TRA-1-60, whereas mecenchymal cells expressed CD44, CD73, CD90, and CD105. Immunohistochemistry showed that both cells expressed the stemness markers Oct3/4, Sox2, Klf4, and SSEA4. Stemness genes' expression in amnion epithelial cells, mesenchymal cells, fibroblast, bone marrow-derived mesenchymal stem cells (MSCs), and induced pluripotent stem cells (iPSCs) was compared by quantitative reverse-transcription polymerase chain reaction (RT-PCR). Amnion-derived epithelial cells and mesenchymal cells expressed Oct3/4, Nanog, and Klf4 more than bone marrow-derived MSCs. The sorted TRA1-60-positive cells expressed Oct3/4, Nanog, and Klf4 more than unsorted cells or TRA1-60-negative cells. TRA1-60 can be a marker for isolating amnion epithelial stem cells.

  9. The Aberrant DNA Methylation Profile of Human Induced Pluripotent Stem Cells Is Connected to the Reprogramming Process and Is Normalized During In Vitro Culture

    PubMed Central

    Tesarova, Lenka; Simara, Pavel; Stejskal, Stanislav; Koutna, Irena

    2016-01-01

    The potential clinical applications of human induced pluripotent stem cells (hiPSCs) are limited by genetic and epigenetic variations among hiPSC lines and the question of their equivalency with human embryonic stem cells (hESCs). We used MethylScreen technology to determine the DNA methylation profile of pluripotency and differentiation markers in hiPSC lines from different source cell types compared to hESCs and hiPSC source cells. After derivation, hiPSC lines compromised a heterogeneous population characterized by variable levels of aberrant DNA methylation. These aberrations were induced during somatic cell reprogramming and their levels were associated with the type of hiPSC source cells. hiPSC population heterogeneity was reduced during prolonged culture and hiPSCs acquired an hESC-like methylation profile. In contrast, the expression of differentiation marker genes in hiPSC lines remained distinguishable from that in hESCs. Taken together, in vitro culture facilitates hiPSC acquisition of hESC epigenetic characteristics. However, differences remain between both pluripotent stem cell types, which must be considered before their use in downstream applications. PMID:27336948

  10. The Aberrant DNA Methylation Profile of Human Induced Pluripotent Stem Cells Is Connected to the Reprogramming Process and Is Normalized During In Vitro Culture.

    PubMed

    Tesarova, Lenka; Simara, Pavel; Stejskal, Stanislav; Koutna, Irena

    2016-01-01

    The potential clinical applications of human induced pluripotent stem cells (hiPSCs) are limited by genetic and epigenetic variations among hiPSC lines and the question of their equivalency with human embryonic stem cells (hESCs). We used MethylScreen technology to determine the DNA methylation profile of pluripotency and differentiation markers in hiPSC lines from different source cell types compared to hESCs and hiPSC source cells. After derivation, hiPSC lines compromised a heterogeneous population characterized by variable levels of aberrant DNA methylation. These aberrations were induced during somatic cell reprogramming and their levels were associated with the type of hiPSC source cells. hiPSC population heterogeneity was reduced during prolonged culture and hiPSCs acquired an hESC-like methylation profile. In contrast, the expression of differentiation marker genes in hiPSC lines remained distinguishable from that in hESCs. Taken together, in vitro culture facilitates hiPSC acquisition of hESC epigenetic characteristics. However, differences remain between both pluripotent stem cell types, which must be considered before their use in downstream applications. PMID:27336948

  11. [Advances in Lung Stem Cells and Lung Cancer Stem Cells].

    PubMed

    Yin, Huijing; Deng, Jiong

    2015-10-20

    Cancer stem cells (CSCs) are emerging as a hot topic for cancer research. Lung CSCs share many characteristics with normal lung stem cells (SCs), including self-renewal and multi-potency for differentiation. Many molecular markers expressed in various types of CSCs were also found in lung CSCs, such as CD133, CD44, aldehyde dehydrogenase (ALDH) and ATP-binding cassette sub-family G member 2 (ABCG2). Similarly, proliferation and expansion of lung CSCs are regulated not only by signal transduction pathways functioning in normal lung SCs, such as Notch, Hedgehog and Wnt pathways, but also by those acting in tumor cells, such as epidermal growth factor receptor (EGFR), signal transducer and activator of transcription 3 (STAT3) and phosphatidylinositol 3 kinase (PI3K) pathways. As CSC plays an critical role in tumor recurrence, metastasis and drug-resistance, understanding the difference between lung CSCs and normal lung SCs, identifying and targeting CSC markers or related signaling pathways may increase the efficacy of therapy on lung cancer and improved survival of lung cancer patients.

  12. Materials as stem cell regulators

    NASA Astrophysics Data System (ADS)

    Murphy, William L.; McDevitt, Todd C.; Engler, Adam J.

    2014-06-01

    The stem cell/material interface is a complex, dynamic microenvironment in which the cell and the material cooperatively dictate one another's fate: the cell by remodelling its surroundings, and the material through its inherent properties (such as adhesivity, stiffness, nanostructure or degradability). Stem cells in contact with materials are able to sense their properties, integrate cues via signal propagation and ultimately translate parallel signalling information into cell fate decisions. However, discovering the mechanisms by which stem cells respond to inherent material characteristics is challenging because of the highly complex, multicomponent signalling milieu present in the stem cell environment. In this Review, we discuss recent evidence that shows that inherent material properties may be engineered to dictate stem cell fate decisions, and overview a subset of the operative signal transduction mechanisms that have begun to emerge. Further developments in stem cell engineering and mechanotransduction are poised to have substantial implications for stem cell biology and regenerative medicine.

  13. Materials as stem cell regulators

    PubMed Central

    Murphy, William L.; McDevitt, Todd C.; Engler, Adam J.

    2014-01-01

    The stem cell/material interface is a complex, dynamic microenvironment in which the cell and the material cooperatively dictate one another's fate: the cell by remodelling its surroundings, and the material through its inherent properties (such as adhesivity, stiffness, nanostructure or degradability). Stem cells in contact with materials are able to sense their properties, integrate cues via signal propagation and ultimately translate parallel signalling information into cell fate decisions. However, discovering the mechanisms by which stem cells respond to inherent material characteristics is challenging because of the highly complex, multicomponent signalling milieu present in the stem cell environment. In this Review, we discuss recent evidence that shows that inherent material properties may be engineered to dictate stem cell fate decisions, and overview a subset of the operative signal transduction mechanisms that have begun to emerge. Further developments in stem cell engineering and mechanotransduction are poised to have substantial implications for stem cell biology and regenerative medicine. PMID:24845994

  14. Immunological properties of embryonic and adult stem cells

    PubMed Central

    Bifari, Francesco; Pacelli, Luciano; Krampera, Mauro

    2010-01-01

    The possibility of treating degenerative diseases by stem cell-based approaches is a promising therapeutical option. Among major concerns for the clinical application of stem cells, some derive from the possibility that stem cells may be rejected by the immune system as a consequence of histoincompatibility and that stem cells themselves may interfere with the normal functions of host immune response. Therefore, the immunogenicity and the immunomodulatory properties of stem cells must be carefully addressed. Although these properties are common features of different stem cell types, some peculiarities can be recognized and characterized for their proper clinical use. PMID:21607122

  15. Dental mesenchymal stem cells.

    PubMed

    Sharpe, Paul T

    2016-07-01

    Mammalian teeth harbour mesenchymal stem cells (MSCs), which contribute to tooth growth and repair. These dental MSCs possess many in vitro features of bone marrow-derived MSCs, including clonogenicity, expression of certain markers, and following stimulation, differentiation into cells that have the characteristics of osteoblasts, chondrocytes and adipocytes. Teeth and their support tissues provide not only an easily accessible source of MSCs but also a tractable model system to study their function and properties in vivo In addition, the accessibility of teeth together with their clinical relevance provides a valuable opportunity to test stem cell-based treatments for dental disorders. This Review outlines some recent discoveries in dental MSC function and behaviour and discusses how these and other advances are paving the way for the development of new biologically based dental therapies. PMID:27381225

  16. [Perinatal sources of stem cells].

    PubMed

    Piskorska-Jasiulewicz, Magdalena Maria; Witkowska-Zimny, Małgorzata

    2015-03-08

    Recently, stem cell biology has become an interesting topic. Several varieties of human stem cells have been isolated and identified in vivo and in vitro. Successful application of hematopoietic stem cells in hematology has led to the search for other sources of stem cells and expanding the scale of their application. Perinatal stem cells are a versatile cell population, and they are interesting for both scientific and practical objectives. Stem cells from perinatal tissue may be particularly useful in the clinic for autologous transplantation for fetuses and newborns, and after banking in later stages of life, as well as for in utero transplantation in the case of genetic disorders. In this review paper we focus on the extraction and therapeutic potential of stem cells derived from perinatal tissues such as the placenta, the amnion, amniotic fluid, umbilical cord blood and Wharton's jelly.

  17. DNA damage response in adult stem cells.

    PubMed

    Insinga, Alessandra; Cicalese, Angelo; Pelicci, Pier Giuseppe

    2014-04-01

    This review discusses the processes of DNA-damage-response and DNA-damage repair in stem and progenitor cells of several tissues. The long life-span of stem cells suggests that they may respond differently to DNA damage than their downstream progeny and, indeed, studies have begun to elucidate the unique stem cell response mechanisms to DNA damage. Because the DNA damage responses in stem cells and progenitor cells are distinctly different, stem and progenitor cells should be considered as two different entities from this point of view. Hematopoietic and mammary stem cells display a unique DNA-damage response, which involves active inhibition of apoptosis, entry into the cell-cycle, symmetric division, partial DNA repair and maintenance of self-renewal. Each of these biological events depends on the up-regulation of the cell-cycle inhibitor p21. Moreover, inhibition of apoptosis and symmetric stem cell division are the consequence of the down-regulation of the tumor suppressor p53, as a direct result of p21 up-regulation. A deeper understanding of these processes is required before these findings can be translated into human anti-aging and anti-cancer therapies. One needs to clarify and dissect the pathways that control p21 regulation in normal and cancer stem cells and define (a) how p21 blocks p53 functions in stem cells and (b) how p21 promotes DNA repair in stem cells. Is this effect dependent on p21s ability to inhibit p53? Such molecular knowledge may pave the way to methods for maintaining short-term tissue reconstitution while retaining long-term cellular and genomic integrity.

  18. Stem cell aging

    PubMed Central

    Muller-Sieburg, Christa; Sieburg, Hans B.

    2009-01-01

    The question whether stem cells age remains an enigma. Traditionally, aging was thought to change the properties of hematopoietic stem cells (HSC). We discuss here a new model of stem cell aging that challenges this view. It is now well-established that the HSC compartment is heterogeneous, consisting of epigenetically fixed subpopulations of HSC that differ in self-renewal and differentiation capacity. New data show that the representation of these HSC subsets changes during aging. HSC that generate lymphocyte-rich progeny are depleted, while myeloid-biased HSC are enriched in the aged HSC compartment. Myeloid-biased HSC, even when isolated from young donors, have most of the characteristics that had been attributed to aged HSC. Thus, the distinct behavior of the HSC isolated from aged hosts is due to the accumulation of myeloid-biased HSC. By extension this means that the properties of individual HSC are not substantially changed during the lifespan of the organism and that aged hosts do not contain many aged HSC. Myeloid-biased HSC give rise to mature cells slowly but contribute for a long time to peripheral hematopoiesis. We propose that such slow, “lazy” HSC are less likely to be transformed and therefore may safely sustain hematopoiesis for a long time. PMID:19066464

  19. Statins and stem cell modulation.

    PubMed

    Xu, Hui; Yang, Yue-Jin; Yang, Tao; Qian, Hai-Yan

    2013-01-01

    Stem cell-based therapy is a promising option for the treatment of ischemic heart diseases. As to a successful stem cell-based therapy, one of the most important issues is that the stable engraftment and survival of implanted stem cells in cardiac microenvironment. There are evidences suggest that pharmacological treatment devoted to regulate stem cell function might represent a potential new therapeutic strategy and are drawing nearer to becoming a part of treatment in clinical settings. Statins could exert cholesterol-independent or pleiotropic effects to cardiovascular system. Recent studies have shown that statins could modulate the biological characteristics and function of various stem cells, thus could be an effective method to facilitate stem cell therapy. This review will focus on statins and their modulation effects on various stem cells.

  20. Ovarian cancer stem cells enrichment.

    PubMed

    Yang, Lijuan; Lai, Dongmei

    2013-01-01

    The concept of cancer stem cells (CSCs) provides a new paradigm for understanding cancer biology. Cancer stem cells are defined as a minority of cancer cells with stem cell properties responsible for maintenance and growth of tumors. The targeting of CSCs is a potential therapeutic strategy to combat ovarian cancer. Ovarian epithelial cancer cells cultured in serum-free medium can form sphere cells. These sphere cells may be enriched for cancer stem cells (CSCs). The isolation of sphere cells from solid tumors is an important technique in studying cancer cell biology. Here we describe the isolation of sphere cells from primary ovarian cancer tissue, ascites fluid, and the cancer cell line SKOV3 with stem cell selection medium. PMID:23913228

  1. Stem cells and somatic cells: reprogramming and plasticity.

    PubMed

    Estrov, Zeev

    2009-01-01

    Recent seminal discoveries have significantly advanced the field of stem cell research and received worldwide attention. Improvements in somatic cell nuclear transfer (SCNT) technology, enabling the cloning of Dolly the sheep, and the derivation and differentiation of human embryonic stem cells raised hopes that normal cells could be generated to replace diseased or injured tissue. At the same time, in vitro and in vivo studies demonstrated that somatic cells of one tissue are capable of generating cells of another tissue. It was theorized that any cell might be reprogrammed, by exposure to a new environment, to become another cell type. This concept contradicts two established hypotheses: (1) that only specific tissues are generated from the endoderm, mesoderm, and ectoderm and (2) that tissue cells arise from a rare population of tissue-specific stem cells in a hierarchical fashion. SCNT, cell fusion experiments, and most recent gene transfer studies also contradict these hypotheses, as they demonstrate that mature somatic cells can be reprogrammed to regain pluripotent (or even totipotent) stem cell capacity. On the basis of the stem cell theory, hierarchical cancer stem cell differentiation models have been proposed. Cancer cell plasticity is an established phenomenon that supports the notion that cellular phenotype and function might be altered. Therefore, mechanisms of cellular plasticity should be exploited and the clinical significance of the cancer stem cell theory cautiously assessed. PMID:19778860

  2. Breast Cancer Stem Cells

    PubMed Central

    Velasco-Velázquez, Marco A.; Homsi, Nora; De La Fuente, Marisol; Pestell, Richard G.

    2012-01-01

    Breast cancer stem cells (BCSCs) constitute a subpopulation of tumor cells that express stem cell-associated markers and have a high capacity for tumor generation in vivo. Identification of BCSCs from tumor samples or breast cancer cell lines has been based mainly on CD44+/CD24−/low or ALDH+ phenotypes. BCSCs isolation has allowed the analysis of the molecular mechanisms involved in their origin, self-renewal, differentiation into tumor cells, resistance to radiation therapy and chemotherapy, and invasiveness and metastatic ability. Molecular genetic analysis using knockout animals and inducible transgenics have identified NF-κB, c-Jun, p21CIP1, and Forkhead-like-protein Dach1 in BCSC expansion and fate. Clinical analyses of BCSCs in breast tumors have found a correlation between the proportion of BCSCs and poor prognosis. Therefore, new therapies that specifically target BCSCs are an urgent need. We summarize recent evidence that partially explain the biological characteristics of BCSCs. PMID:22249027

  3. Calcium signaling in pluripotent stem cells.

    PubMed

    Apáti, Ágota; Pászty, Katalin; Erdei, Zsuzsa; Szebényi, Kornélia; Homolya, László; Sarkadi, Balázs

    2012-04-28

    Pluripotent stem cells represent a new source of biological material allowing the exploration of signaling phenomena during normal cell development and differentiation. Still, the calcium signaling pathways and intracellular calcium responses to various ligands or stress conditions have not been sufficiently explored as yet in embryonic or induced pluripotent stem cells and in their differentiated offspring. This is partly due to the special culturing conditions of these cell types, the rapid morphological and functional changes in heterogeneous cell populations during early differentiation, and methodological problems in cellular calcium measurements. In this paper, we review the currently available data in the literature on calcium signaling in pluripotent stem cells and discuss the potential shortcomings of these studies. Various assay methods are surveyed for obtaining reliable data both in undifferentiated embryonic stem cells and in specific, stem cell-derived human tissues. In this paper, we present the modulation of calcium signaling in human embryonic stem cells (hESC) and in their derivates; mesenchymal stem cell like (MSCl) cells and cardiac tissues using the fluorescent calcium indicator Fluo-4 and confocal microscopy. LPA, trypsin and angiotensin II were effective in inducing calcium signals both in HUES9 and MSCl cells. Histamine and thrombin induced calcium signal exclusively in the MSCl cells, while ATP was effective only in HUES9 cells. There was no calcium signal evoked by GABA, even at relatively high concentrations. In stem cell-derived cardiomyocytes a rapid increase in the beating rate and an increase of the calcium signal peaks could be observed after the addition of adrenaline, while verapamil led to a strong decrease in cellular calcium and stopped spontaneous contractions in a relaxed state.

  4. Impaired Telomere Maintenance and Decreased Canonical WNT Signaling but Normal Ribosome Biogenesis in Induced Pluripotent Stem Cells from X-Linked Dyskeratosis Congenita Patients

    PubMed Central

    Gu, Bai-Wei; Apicella, Marisa; Mills, Jason; Fan, Jian-Meng; Reeves, Dara A.; French, Deborah; Podsakoff, Gregory M.; Bessler, Monica; Mason, Philip J.

    2015-01-01

    Dyskeratosis congenita (DC) is an inherited bone marrow failure syndrome characterized by the presence of short telomeres at presentation. Mutations in ten different genes, whose products are involved in the telomere maintenance pathway, have been shown to cause DC. The X-linked form is the most common form of the disease and is caused by mutations in the gene DKC1, encoding the protein dyskerin. Dyskerin is required for the assembly and stability of telomerase and is also involved in ribosomal RNA (rRNA) processing where it converts specific uridines to pseudouridine. DC is thought to result from failure to maintain tissues, like blood, that are renewed by stem cell activity, but research into pathogenic mechanisms has been hampered by the difficulty of obtaining stem cells from patients. We reasoned that induced pluripotent stem (iPS) cells from X-linked DC patients may provide information about the mechanisms involved. Here we describe the production of iPS cells from DC patients with DKC1 mutations Q31E, A353V and ΔL37. In addition we constructed “corrected” lines with a copy of the wild type dyskerin cDNA expressed from the AAVS1 safe harbor locus. We show that in iPS cells with DKC1 mutations telomere maintenance is compromised with short telomere lengths and decreased telomerase activity. The degree to which telomere lengths are affected by expression of telomerase during reprograming, or with ectopic expression of wild type dyskerin, is variable. The recurrent mutation A353V shows the most severe effect on telomere maintenance. A353V cells but not Q31E or ΔL37 cells, are refractory to correction by expression of wild type DKC1 cDNA. Because dyskerin is involved in both telomere maintenance and ribosome biogenesis it has been postulated that defective ribosome biogenesis and translation may contribute to the disease phenotype. Evidence from mouse and zebra fish models has supported the involvement of ribosome biogenesis but primary cells from human

  5. Pancreatic cancer stem cells

    PubMed Central

    Zhu, Ya-Yun; Yuan, Zhou

    2015-01-01

    Studies are emerging in support of the cancer stem cells (CSCs) theory which considers that a tiny subset of cancer cells is exclusively responsible for the initiation and malignant behavior of a cancer. This cell population, also termed CSCs, possesses the capacity both to self-renew, producing progeny that have the identical tumorigenic potential, and to differentiate into the bulk of cancer cells, helping serve the formation of the tumor entities, which, altogether, build the hierarchically organized structure of a cancer. In this review, we try to articulate the complicated signaling pathways regulating the retention of the characteristics of pancreatic CSCs, and in the wake of which, we seek to offer insights into the CSCs-relevant targeted therapeutics which are, in the meantime, confronted with bigger challenges than ever. PMID:26045976

  6. Regulation of breast cancer stem cell features.

    PubMed

    Czerwinska, Patrycja; Kaminska, Bozena

    2015-01-01

    Cancer stem cells (CSCs) are rare, tumour-initiating cells that exhibit stem cell properties: capacity of self-renewal, pluripotency, highly tumorigenic potential, and resistance to therapy. Cancer stem cells have been characterised and isolated from many cancers, including breast cancer. Developmental pathways, such as the Wnt/β-catenin, Notch/γ-secretase/Jagged, Shh (sonic hedgehog), and BMP signalling pathways, which direct proliferation and differentiation of normal stem cells, have emerged as major signalling pathways that contribute to the self-renewal of stem and/or progenitor cells in a variety of organs and cancers. Deregulation of these signalling pathways is frequently linked to an epithelial-mesenchymal transition (EMT), and breast CSCs often possess properties of cells that have undergone the EMT process. Signalling networks mediated by microRNAs and EMT-inducing transcription factors tie the EMT process to regulatory networks that maintain "stemness". Recent studies have elucidated epigenetic mechanisms that control pluripotency and stemness, which allows an assessment on how embryonic and normal tissue stem cells are deregulated during cancerogenesis to give rise to CSCs. Epigenetic-based mechanisms are reversible, and the possibility of "resetting" the abnormal cancer epigenome by applying pharmacological compounds targeting epigenetic enzymes is a promising new therapeutic strategy. Chemoresistance of CSCs is frequently driven by various mechanisms, including aberrant expression/activity of ABC transporters, aldehyde dehydrogenase and anti-oncogenic proteins (i.e. BCL2, B-cell lymphoma-2), enhanced DNA damage response, activation of pro-survival signalling pathways, and epigenetic deregulations. Despite controversy surrounding the CSC hypothesis, there is substantial evidence for their role in cancer, and a number of drugs intended to specifically target CSCs have entered clinical trials. PMID:25691826

  7. Stem cells and neurodegenerative diseases.

    PubMed

    Hou, LingLing; Hong, Tao

    2008-04-01

    Neurodegenerative diseases are characterized by the neurodegenerative changes or apoptosis of neurons involved in networks, which are important to specific physiological functions. With the development of old-aging society, the incidence of neurodegenerative diseases is on the increase. However, it is difficult to diagnose for most of neurodegenerative diseases. At present, there are too few effective therapies. Advances in stem cell biology have raised the hope and possibility for the therapy of neurodegenerative diseases. Recently, stem cells have been widely attempted to treat neurodegenerative diseases of animal model. Here we review the progress and prospects of various stem cells, including embryonic stem cells, mesenchymal stem cell and neural stem cells and so on, for the treatments of neurodegenerative diseases, such as Parkinson's disease, Alzheimer's disease, Huntington' disease and Amyotrophic lateral sclerosis/Lou Gehrig's disease.

  8. Cancer stem cells in glioblastoma

    PubMed Central

    Lathia, Justin D.; Mack, Stephen C.; Mulkearns-Hubert, Erin E.; Valentim, Claudia L.L.; Rich, Jeremy N.

    2015-01-01

    Tissues with defined cellular hierarchies in development and homeostasis give rise to tumors with cellular hierarchies, suggesting that tumors recapitulate specific tissues and mimic their origins. Glioblastoma (GBM) is the most prevalent and malignant primary brain tumor and contains self-renewing, tumorigenic cancer stem cells (CSCs) that contribute to tumor initiation and therapeutic resistance. As normal stem and progenitor cells participate in tissue development and repair, these developmental programs re-emerge in CSCs to support the development and progressive growth of tumors. Elucidation of the molecular mechanisms that govern CSCs has informed the development of novel targeted therapeutics for GBM and other brain cancers. CSCs are not self-autonomous units; rather, they function within an ecological system, both actively remodeling the microenvironment and receiving critical maintenance cues from their niches. To fulfill the future goal of developing novel therapies to collapse CSC dynamics, drawing parallels to other normal and pathological states that are highly interactive with their microenvironments and that use developmental signaling pathways will be beneficial. PMID:26109046

  9. Skeletal stem cells

    PubMed Central

    Bianco, Paolo; Robey, Pamela G.

    2015-01-01

    Skeletal stem cells (SSCs) reside in the postnatal bone marrow and give rise to cartilage, bone, hematopoiesis-supportive stroma and marrow adipocytes in defined in vivo assays. These lineages emerge in a specific sequence during embryonic development and post natal growth, and together comprise a continuous anatomical system, the bone-bone marrow organ. SSCs conjoin skeletal and hematopoietic physiology, and are a tool for understanding and ameliorating skeletal and hematopoietic disorders. Here and in the accompanying poster, we concisely discuss the biology of SSCs in the context of the development and postnatal physiology of skeletal lineages, to which their use in medicine must remain anchored. PMID:25758217

  10. Mechanotransduction: Tuning Stem Cells Fate

    PubMed Central

    D'Angelo, Francesco; Tiribuzi, Roberto; Armentano, Ilaria; Kenny, Josè Maria; Martino, Sabata; Orlacchio, Aldo

    2011-01-01

    It is a general concern that the success of regenerative medicine-based applications is based on the ability to recapitulate the molecular events that allow stem cells to repair the damaged tissue/organ. To this end biomaterials are designed to display properties that, in a precise and physiological-like fashion, could drive stem cell fate both in vitro and in vivo. The rationale is that stem cells are highly sensitive to forces and that they may convert mechanical stimuli into a chemical response. In this review, we describe novelties on stem cells and biomaterials interactions with more focus on the implication of the mechanical stimulation named mechanotransduction. PMID:24956164

  11. Stem Cells, Redox Signaling, and Stem Cell Aging

    PubMed Central

    Liang, Raymond

    2014-01-01

    Abstract Significance: Functional stem cell decline has been postulated to result in loss of maintenance of tissue homeostasis leading to organismal decline and diseases of aging. Recent Advances: Recent findings implicate redox metabolism in the control of stem cell pool and stem cell aging. Although reactive oxygen species (ROS) are better known for their damaging properties to DNA, proteins and lipids, recent findings suggest that ROS may also be an integral physiological mediator of cellular signaling in primary cells. Critical Issues: Here we review recent published work on major signaling pathways and transcription factors that are regulated by ROS and mediate ROS regulation of stem cell fate. We will specifically focus on how alterations in this regulation may be implicated in disease and particularly in diseases of stem cell aging. In general, based on the work described here we propose a model in which ROS function as stem cell rheostat. Future Directions: Future work in elucidating how ROS control stem cell cycling, apoptotic machinery, and lineage determination should shed light on mechanisms whereby ROS may control stem cell aging. Antioxid. Redox Signal. 20, 1902–1916. PMID:24383555

  12. Glucose-responsive insulin-producing cells from stem cells.

    PubMed

    Kaczorowski, David J; Patterson, Ethan S; Jastromb, William E; Shamblott, Michael J

    2002-01-01

    Recent success with immunosuppression following islet cell transplantation offers hope that a cell transplantation treatment for type 1 (juvenile) diabetes may be possible if sufficient quantities of safe and effective cells can be produced. For the treatment of type 1 diabetes, the two therapeutically essential functions are the ability to monitor blood glucose levels and the production of corresponding and sufficient levels of mature insulin to maintain glycemic control. Stem cells can replicate themselves and produce cells that take on more specialized functions. If a source of stem cells capable of yielding glucose-responsive insulin-producing (GRIP) cells can be identified, then transplantation-based treatment for type 1 diabetes may become widely available. Currently, stem cells from embryonic and adult sources are being investigated for their ability to proliferate and differentiate into cells with GRIP function. Human embryonic pluripotent stem cells, commonly referred to as embryonic stem (ES) cells and embryonic germ (EG) cells, have received significant attention owing to their broad capacity to differentiate and ability to proliferate well in culture. Their application to diabetes research is of particular promise, as it has been demonstrated that mouse ES cells are capable of producing cells able to normalize glucose levels of diabetic mice, and human ES cells can differentiate into cells capable of insulin production. Cells with GRIP function have also been derived from stem cells residing in adult organisms, here referred to as endogenous stem cell sources. Independent of source, stem cells capable of producing cells with GRIP function may provide a widely available cell transplantation treatment for type 1 diabetes. PMID:12469358

  13. Telomeres, stem cells, and hematology

    PubMed Central

    2008-01-01

    Telomeres are highly dynamic structures that adjust the cellular response to stress and growth stimulation based on previous cell divisions. This critical function is accomplished by progressive telomere shortening and DNA damage responses activated by chromosome ends without sufficient telomere repeats. Repair of critically short telomeres by telomerase or recombination is limited in most somatic cells, and apoptosis or cellular senescence is triggered when too many uncapped telomeres accumulate. The chance of the latter increases as the average telomere length decreases. The average telomere length is set and maintained in cells of the germ line that typically express high levels of telomerase. In somatic cells, the telomere length typically declines with age, posing a barrier to tumor growth but also contributing to loss of cells with age. Loss of (stem) cells via telomere attrition provides strong selection for abnormal cells in which malignant progression is facilitated by genome instability resulting from uncapped telomeres. The critical role of telomeres in cell proliferation and aging is illustrated in patients with 50% of normal telomerase levels resulting from a mutation in one of the telomerase genes. Here, the role of telomeres and telomerase in human biology is reviewed from a personal historical perspective. PMID:18263784

  14. [Stem cells and cardiac regeneration].

    PubMed

    Perez Millan, Maria Ines; Lorenti, Alicia

    2006-01-01

    Stem cells are defined by virtue of their functional attributes: absence of tissue specific differentitated markers, capable of proliferation, able to self-maintain the population, able to produce a large number of differentiated, functional progeny, able to regenerate the tissue after injury. Cell therapy is an alternative for the treatment of several diseases, like cardiac diseases (cell cardiomyoplasty). A variety of stem cells could be used for cardiac repair: from cardiac and extracardiac sources. Each cell type has its own profile of advantages, limitations, and practicability issues in specific clinical settings. Differentiation of bone marrow stem cells to cardiomyocyte-like cells have been observed under different culture conditions. The presence of resident cardiac stem cell population capable of differentiation into cardiomyocyte or vascular lineage suggests that these cells could be used for cardiac tissue repair, and represent a great promise for clinical application. Stem cells mobilization by cytokines may also offer a strategy for cardiac regeneration. The use of stem cells (embryonic and adult) may hold the key to replacing cells lost in many devastating diseases. This potential benefit is a major focus for stem cell research.

  15. Regulation of breast cancer stem cell features

    PubMed Central

    Kaminska, Bozena

    2015-01-01

    Cancer stem cells (CSCs) are rare, tumour-initiating cells that exhibit stem cell properties: capacity of self-renewal, pluripotency, highly tumorigenic potential, and resistance to therapy. Cancer stem cells have been characterised and isolated from many cancers, including breast cancer. Developmental pathways, such as the Wnt/β-catenin, Notch/γ-secretase/Jagged, Shh (sonic hedgehog), and BMP signalling pathways, which direct proliferation and differentiation of normal stem cells, have emerged as major signalling pathways that contribute to the self-renewal of stem and/or progenitor cells in a variety of organs and cancers. Deregulation of these signalling pathways is frequently linked to an epithelial-mesenchymal transition (EMT), and breast CSCs often possess properties of cells that have undergone the EMT process. Signalling networks mediated by microRNAs and EMT-inducing transcription factors tie the EMT process to regulatory networks that maintain “stemness”. Recent studies have elucidated epigenetic mechanisms that control pluripotency and stemness, which allows an assessment on how embryonic and normal tissue stem cells are deregulated during cancerogenesis to give rise to CSCs. Epigenetic-based mechanisms are reversible, and the possibility of “resetting” the abnormal cancer epigenome by applying pharmacological compounds targeting epigenetic enzymes is a promising new therapeutic strategy. Chemoresistance of CSCs is frequently driven by various mechanisms, including aberrant expression/activity of ABC transporters, aldehyde dehydrogenase and anti-oncogenic proteins (i.e. BCL2, B-cell lymphoma-2), enhanced DNA damage response, activation of pro-survival signalling pathways, and epigenetic deregulations. Despite controversy surrounding the CSC hypothesis, there is substantial evidence for their role in cancer, and a number of drugs intended to specifically target CSCs have entered clinical trials. PMID:25691826

  16. Involvement of Plant Stem Cells or Stem Cell-Like Cells in Dedifferentiation.

    PubMed

    Jiang, Fangwei; Feng, Zhenhua; Liu, Hailiang; Zhu, Jian

    2015-01-01

    Dedifferentiation is the transformation of cells from a given differentiated state to a less differentiated or stem cell-like state. Stem cell-related genes play important roles in dedifferentiation, which exhibits similar histone modification and DNA methylation features to stem cell maintenance. Hence, stem cell-related factors possibly synergistically function to provide a specific niche beneficial to dedifferentiation. During callus formation in Arabidopsis petioles, cells adjacent to procambium cells (stem cell-like cells) are dedifferentiated and survive more easily than other cell types. This finding indicates that stem cells or stem cell-like cells may influence the dedifferentiating niche. In this paper, we provide a brief overview of stem cell maintenance and dedifferentiation regulation. We also summarize current knowledge of genetic and epigenetic mechanisms underlying the balance between differentiation and dedifferentiation. Furthermore, we discuss the correlation of stem cells or stem cell-like cells with dedifferentiation. PMID:26635851

  17. CD117+ amniotic fluid stem cells

    PubMed Central

    Cananzi, Mara; De Coppi, Paolo

    2012-01-01

    Broadly multipotent stem cells can be isolated from amniotic fluid by selection for the expression of the membrane stem cell factor receptor c-Kit, a common marker for multipotential stem cells. They have clonogenic capability and can be directed into a wide range of cell types representing the three primary embryonic lineages. Amniotic fluid stem cells maintained for over 250 population doublings retained long telomeres and a normal karyotype. Clonal human lines verified by retroviral marking were induced to differentiate into cell types representing each embryonic germ layer, including cells of adipogenic, osteogenic, myogenic, endothelial, neuronal and hepatic lineages. AFS cells could be differentiate toward cardiomyogenic lineages, when co-cultured with neonatal cardiomyocytes, and have the potential to generate myogenic and hematopoietic lineages both in vitro and in vivo. Very recently first trimester AFS cells could be reprogrammed without any genetic manipulation opening new possibilities in the field of fetal/neonatal therapy and disease modeling. In this review we are aiming to summarize the knowledge on amniotic fluid stem cells and highlight the most promising results. PMID:23037870

  18. Adult Stem and Progenitor Cells

    NASA Astrophysics Data System (ADS)

    Geraerts, Martine; Verfaillie, Catherine M.

    The discovery of adult stem cells in most adult tissues is the basis of a number of clinical studies that are carried out, with therapeutic use of hematopoietic stem cells as a prime example. Intense scientific debate is still ongoing as to whether adult stem cells may have a greater plasticity than previously thought. Although cells with some features of embryonic stem cells that, among others, express Oct4, Nanog and SSEA1 are isolated from fresh tissue, it is not clear if the greater differentiation potential is acquired during cell culture. Moreover, adult more pluripotent cells do not have all pluripotent characteristics typical for embryonic stem cells. Recently, some elegant studies were published in which adult cells could be completely reprogrammed to embryonic stem cell-like cells by overexpression of some key transcription factors for pluripotency (Oct4, Sox2, Klf4 and c-Myc). It will be interesting for the future to investigate the exact mechanisms underlying this reprogramming and whether similar transcription factor pathways are present and/or can be activated in adult more pluripotent stem cells.

  19. The new stem cell biology.

    PubMed Central

    Quesenberry, Peter J.; Colvin, Gerald A.; Lambert, Jean-Francois; Frimberger, Angela E.; Dooner, Mark S.; Mcauliffe, Christina I.; Miller, Caroline; Becker, Pamela; Badiavas, Evangelis; Falanga, Vincent J.; Elfenbein, Gerald; Lum, Lawrence G.

    2002-01-01

    Recent studies have indicated that bone marrow stem cells are capable of generating muscle, cardiac, hepatic, renal, and bone cells. Purified hematopoietic stem cells have generated cardiac and hepatic cells and reversed disease manifestations in these tissues. Hematopoietic stem cells also alter phenotype with cell cycle transit or circadian phase. During a cytokine stimulated cell cycle transit, reversible alterations of differentiation and engraftment occur. Primitive hematopoietic stem cells express a wide variety of adhesion and cytokine receptors and respond quickly with migration and podia extensions on exposure to cytokines. These data suggest an "Open Chromatin" model of stem cell regulation in which there is a fluctuating continuum in the stem cell/progenitor cell compartments, rather than a hierarchical relationship. These observations, along with progress in using low dose treatments and tolerization approaches, suggest many new therapeutic strategies involving stem cells and the creation of a new medical specialty; stemology. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 PMID:12053709

  20. 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

  1. Bioprinting for stem cell research

    PubMed Central

    Tasoglu, Savas; Demirci, Utkan

    2012-01-01

    Recently, there has been a growing interest to apply bioprinting techniques to stem cell research. Several bioprinting methods have been developed utilizing acoustics, piezoelectricity, and lasers to deposit living cells onto receiving substrates. Using these technologies, spatially defined gradients of immobilized proteins can be engineered to direct stem cell differentiation into multiple subpopulations of different lineages. Stem cells can also be patterned in a high-throughput manner onto flexible implementation patches for tissue regeneration or onto substrates with the goal of accessing encapsulated stem cell of interest for genomic analysis. Here, we review recent achievements with bioprinting technologies in stem cell research, and identify future challenges and potential applications including tissue engineering and regenerative medicine, wound healing, and genomics. PMID:23260439

  2. Stem cells for spine surgery.

    PubMed

    Schroeder, Joshua; Kueper, Janina; Leon, Kaplan; Liebergall, Meir

    2015-01-26

    In the past few years, stem cells have become the focus of research by regenerative medicine professionals and tissue engineers. Embryonic stem cells, although capable of differentiating into cell lineages of all three germ layers, are limited in their utilization due to ethical issues. In contrast, the autologous harvest and subsequent transplantation of adult stem cells from bone marrow, adipose tissue or blood have been experimentally utilized in the treatment of a wide variety of diseases ranging from myocardial infarction to Alzheimer's disease. The physiologic consequences of stem cell transplantation and its impact on functional recovery have been studied in countless animal models and select clinical trials. Unfortunately, the bench to bedside translation of this research has been slow. Nonetheless, stem cell therapy has received the attention of spinal surgeons due to its potential benefits in the treatment of neural damage, muscle trauma, disk degeneration and its potential contribution to bone fusion.

  3. System for tracking transplanted limbal epithelial stem cells in the treatment of corneal stem cell deficiency

    NASA Astrophysics Data System (ADS)

    Boadi, J.; Sangwal, V.; MacNeil, S.; Matcher, S. J.

    2015-03-01

    The prevailing hypothesis for the existence and healing of the avascular corneal epithelium is that this layer of cells is continually produced by stem cells in the limbus and transported onto the cornea to mature into corneal epithelium. Limbal Stem Cell Deficiency (LSCD), in which the stem cell population is depleted, can lead to blindness. LSCD can be caused by chemical and thermal burns to the eye. A popular treatment, especially in emerging economies such as India, is the transplantation of limbal stem cells onto damaged limbus with hope of repopulating the region. Hence regenerating the corneal epithelium. In order to gain insights into the success rates of this treatment, new imaging technologies are needed in order to track the transplanted cells. Optical Coherence Tomography (OCT) is well known for its high resolution in vivo images of the retina. A custom OCT system has been built to image the corneal surface, to investigate the fate of transplanted limbal stem cells. We evaluate two methods to label and track transplanted cells: melanin labelling and magneto-labelling. To evaluate melanin labelling, stem cells are loaded with melanin and then transplanted onto a rabbit cornea denuded of its epithelium. The melanin displays strongly enhanced backscatter relative to normal cells. To evaluate magneto-labelling the stem cells are loaded with magnetic nanoparticles (20-30nm in size) and then imaged with a custom-built, magneto-motive OCT system.

  4. The advantages of hair follicle pluripotent stem cells over embryonic stem cells and induced pluripotent stem cells for regenerative medicine.

    PubMed

    Amoh, Yasuyuki; Katsuoka, Kensei; Hoffman, Robert M

    2010-12-01

    Multipotent adult stem cells have many potential therapeutic applications. Our recent findings suggest that hair follicles are a promising source of easily accessible multipotent stem cells. Stem cells in the hair follicle area express the neural stem cell marker nestin, suggesting that hair-follicle stem cells and neural stem cells have common features. Nestin-expressing hair follicle stem cells can form neurons and other cell types, and thus adult hair follicle stem cells could have important therapeutic applications, particularly for neurologic diseases. Transplanted hair follicle stem cells promote the functional recovery of injured peripheral nerve and spinal cord. Recent findings suggest that direct transplantation of hair-follicle stem cells without culture can promote nerve repair, which makes them potentially clinically practical. Human hair follicle stem cells as well as mouse hair follicle stem cells promote nerve repair and can be applied to test the hypothesis that human hair follicle stem cells can provide a readily available source of neurologically therapeutic stem cells. The use of hair follicle stem cells for nerve regeneration overcomes critical problems of embryonic stem cells or induced pluripotent stem cells in that the hair follicle stem cells are multipotent, readily accessible, non-oncogenic, and are not associated with ethical issues.

  5. Stem cells, colorectal cancer and cancer stem cell markers correlations.

    PubMed

    Cherciu, Irina; Bărbălan, A; Pirici, D; Mărgăritescu, C; Săftoiu, A

    2014-01-01

    : The idea of stem cells as being progenitors of cancer was initially controversial, but later supported by research in the field of leukemia and solid tumors. Afterwards, it was established that genetic abnormalities can affect the stem and progenitor cells, leading to uncontrolled replication and deregulated differentiation. These alterations will cause the changeover to cancerous stem cells (CSC) having two main characteristics: tumor initiation and maintenance. This review will focus on the colorectal cancer stem cell (CR-CSCs) theory which provides a better understanding of different tumor processes: initiation, aggressive growth, recurrence, treatment resistance and metastasis. A search in PubMed/Medline was performed using the following keywords: colorectal cancer stem cells (CR-CSCs), colorectal neoplasms stem cells, colorectal cancer stem cell (CR-CSCs) markers, etc. Electronic searches were supplemented by hand searching reference lists, abstracts and proceedings from meetings. Isolation of CR-CSCs can be achieved by targeting and selecting subpopulation of tumor cells based on expression of one or multiple cell surface markers associated with cancer self-renewal, markers as: CD133, CD166, CD44, CD24, beta1 integrin-CD29, Lgr5, EpCAM (ESA), ALDH-1, Msi-1, DCAMLK1 or EphB receptors. The identification and localization of CR-CSCs through different markers will hopefully lead to a better stratification of prognosis and treatment response, as well as the development of new effective strategies for cancer management.

  6. FDA Warns About Stem Cell Claims

    MedlinePlus

    ... Home For Consumers Consumer Updates FDA Warns About Stem Cell Claims Share Tweet Linkedin Pin it More sharing ... blood-forming system. back to top Regulation of Stem Cells FDA regulates stem cells in the U.S. to ...

  7. LncRNAs in Stem Cells

    PubMed Central

    Hu, Shanshan; Shan, Ge

    2016-01-01

    Noncoding RNAs are critical regulatory factors in essentially all forms of life. Stem cells occupy a special position in cell biology and Biomedicine, and emerging results show that multiple ncRNAs play essential roles in stem cells. We discuss some of the known ncRNAs in stem cells such as embryonic stem cells, induced pluripotent stem cells, mesenchymal stem cells, adult stem cells, and cancer stem cells with a focus on long ncRNAs. Roles and functional mechanisms of these lncRNAs are summarized, and insights into current and future studies are presented. PMID:26880946

  8. Stem cells: review and update.

    PubMed

    Sylvester, Karl G; Longaker, Michael T

    2004-01-01

    Regenerative medicine and emerging biotechnologies stand to revolutionize the practice of medicine. Advancements in stem cell biology, including embryonic and postnatal somatic stem cells, have made the prospect of tissue regeneration a potential clinical reality. Short of reproductive cloning, these same technologies, properly used, could allow for the creation of replacement tissue for the deficient host. To provide a concise review for surgeons on the current science and biology of stem cells, we surveyed the scientific literature, MEDLINE, and relevant political headlines that illuminate the stem cell discussion; the issues are summarized in this review. Building on this conceptual framework, the related issues of clinical promise and the political debate enveloping this emerging technology are examined. A basic understanding of stem cell biology is paramount to stay informed of this emerging technology and the national debate.

  9. The role of non-coding RNAs in the regulation of stem cells and progenitors in the normal mammary gland and in breast tumors

    PubMed Central

    Tordonato, Chiara; Di Fiore, Pier Paolo; Nicassio, Francesco

    2015-01-01

    The outlook on stem cell (SC) biology is shifting from a rigid hierarchical to a more flexible model in which the identity and the behavior of adult SCs, far from being fixed, are determined by the dynamic integration of cell autonomous and non-autonomous mechanisms. Within this framework, the recent discovery of thousands of non-coding RNAs (ncRNAs) with regulatory function is redefining the landscape of transcriptome regulation, highlighting the interplay of epigenetic, transcriptional, and post-transcriptional mechanisms in the specification of cell fate and in the regulation of developmental processes. Furthermore, the expression of ncRNAs is often tissue- or even cell type-specific, emphasizing their involvement in defining space, time and developmental stages in gene regulation. Such a role of ncRNAs has been investigated in embryonic and induced pluripotent SCs, and in numerous types of adult SCs and progenitors, including those of the breast, which will be the topic of this review. We will focus on ncRNAs with an important role in breast cancer, in particular in mammary cancer SCs and progenitors, and highlight the ncRNA-based circuitries whose subversion alters a number of the epigenetic, transcriptional, and post-transcriptional events that control “stemness” in the physiological setting. PMID:25774169

  10. Stem Cells, Retinal Ganglion Cells, and Glaucoma

    PubMed Central

    Sluch, Valentin M.; Zack, Donald J.

    2015-01-01

    Retinal ganglion cells represent an essential neuronal cell type for vision. These cells receive inputs from light-sensing photoreceptors via retinal interneurons and then relay these signals to the brain for further processing. Retinal ganglion cell diseases that result in cell death, e.g. glaucoma, often lead to permanent damage since mammalian nerves do not regenerate. Stem cell differentiation can generate cells needed for replacement or can be used to generate cells capable of secreting protective factors to promote survival. In addition, stem cell-derived cells can be used in drug screening research. Here, we discuss the current state of stem cell research potential for interference in glaucoma and other optic nerve diseases with a focus on stem cell differentiation to retinal ganglion cells. PMID:24732765

  11. Gastrointestinal stem cell up-to-date.

    PubMed

    Pirvulet, V

    2015-01-01

    Cellular and tissue regeneration in the gastrointestinal tract depends on stem cells with properties of self-renewal, clonogenicity, and multipotency. Progress in stem cell research and the identification of potential gastric, intestinal, colonic stem cells new markers and the signaling pathways provide hope for the use of stem cells in regenerative medicine and treatments for disease. This review provides an overview of the different types of stem cells, focusing on tissue-restricted adult stem cells.

  12. Cell proliferation in normal epidermis

    SciTech Connect

    Weinstein, G.D.; McCullough, J.L.; Ross, P.

    1984-06-01

    A detailed examination of cell proliferation kinetics in normal human epidermis is presented. Using tritiated thymidine with autoradiographic techniques, proliferative and differentiated cell kinetics are defined and interrelated. The proliferative compartment of normal epidermis has a cell cycle duration (Tc) of 311 h derived from 3 components: the germinative labeling index (LI), the duration of DNA synthesis (ts), and the growth fraction (GF). The germinative LI is 2.7% +/- 1.2 and ts is 14 h, the latter obtained from a composite fraction of labeled mitoses curve obtained from 11 normal subjects. The GF obtained from the literature and from human skin xenografts to nude mice is estimated to be 60%. Normal-appearing epidermis from patients with psoriasis appears to have a higher proliferation rate. The mean LI is 4.2% +/- 0.9, approximately 50% greater than in normal epidermis. Absolute cell kinetic values for this tissue, however, cannot yet be calculated for lack of other information on ts and GF. A kinetic model for epidermal cell renewal in normal epidermis is described that interrelates the rate of birth/entry, transit, and/or loss of keratinocytes in the 3 epidermal compartments: proliferative, viable differentiated (stratum malpighii), and stratum corneum. Expected kinetic homeostasis in the epidermis is confirmed by the very similar ''turnover'' rates in each of the compartments that are, respectively, 1246, 1417, and 1490 cells/day/mm2 surface area. The mean epidermal turnover time of the entire tissue is 39 days. The Tc of 311 h in normal cells in 8-fold longer than the psoriatic Tc of 36 h and is necessary for understanding the hyperproliferative pathophysiologic process in psoriasis.

  13. Ca2+ signaling in human induced pluripotent stem cell-derived cardiomyocytes (iPS-CM) from normal and catecholaminergic polymorphic ventricular tachycardia (CPVT)-afflicted subjects.

    PubMed

    Zhang, X-H; Haviland, S; Wei, H; Sarić, T; Fatima, A; Hescheler, J; Cleemann, L; Morad, M

    2013-08-01

    Derivation of cardiomyocytes from induced pluripotent stem cells (iPS-CMs) allowed us to probe the Ca(2+)-signaling parameters of human iPS-CMs from healthy- and catecholaminergic polymorphic ventricular tachycardia (CPVT1)-afflicted individuals carrying a novel point mutation p.F2483I in ryanodine receptors (RyR2). iPS-CMs were dissociated on day 30-40 of differentiation and patch-clamped within 3-6 days. Calcium currents (ICa) averaged ∼8pA/pF in control and mutant iPS-CMs. ICa-induced Ca(2+)-transients in control and mutant cells had bell-shaped voltage-dependence similar to that of ICa, consistent with Ca(2+)-induced Ca(2+)-release (CICR) mechanism. The ratio of ICa-activated to caffeine-triggered Ca(2+)-transients was ∼0.3 in both cell types. Caffeine-induced Ca(2+)-transients generated significantly smaller Na(+)-Ca(2+) exchanger current (INCX) in mutant cells, reflecting their smaller Ca(2+)-stores. The gain of CICR was voltage-dependent as in adult cardiomyocytes. Adrenergic agonists enhanced ICa, but differentially altered the CICR gain, diastolic Ca(2+), and Ca(2+)-sparks in mutant cells. The mutant cells, when Ca(2+)-overloaded, showed longer and wandering Ca(2+)-sparks that activated adjoining release sites, had larger CICR gain at -30mV yet smaller Ca(2+)-stores. We conclude that control and mutant iPS-CMs express the adult cardiomyocyte Ca(2+)-signaling phenotype. RyR2 F2483I mutant myocytes have aberrant unitary Ca(2+)-signaling, smaller Ca(2+)-stores, higher CICR gains, and sensitized adrenergic regulation, consistent with functionally altered Ca(2+)-release profile of CPVT syndrome. PMID:23684427

  14. A Comparison of Culture Characteristics between Human Amniotic Mesenchymal Stem Cells and Dental Stem Cells.

    PubMed

    Yusoff, Nurul Hidayat; Alshehadat, Saaid Ayesh; Azlina, Ahmad; Kannan, Thirumulu Ponnuraj; Hamid, Suzina Sheikh Abdul

    2015-04-01

    In the past decade, the field of stem cell biology is of major interest among researchers due to its broad therapeutic potential. Stem cells are a class of undifferentiated cells that are able to differentiate into specialised cell types. Stem cells can be classified into two main types: adult stem cells (adult tissues) and embryonic stem cells (embryos formed during the blastocyst phase of embryological development). This review will discuss two types of adult mesenchymal stem cells, dental stem cells and amniotic stem cells, with respect to their differentiation lineages, passage numbers and animal model studies. Amniotic stem cells have a greater number of differentiation lineages than dental stem cells. On the contrary, dental stem cells showed the highest number of passages compared to amniotic stem cells. For tissue regeneration based on animal studies, amniotic stem cells showed the shortest time to regenerate in comparison with dental stem cells.

  15. Cell rheology: Stressed-out stem cells

    NASA Astrophysics Data System (ADS)

    Holle, Andrew W.; Engler, Adam J.

    2010-01-01

    Experiments have shown that the physical characteristics of the matrix surrounding a stem cell can affect its behaviour. This picture gets further complicated by studies of stem cells and their differentiated counterparts that show that the cells' own softness also has a clear role in how they respond to stress.

  16. Stem cell therapy without the cells

    PubMed Central

    Maguire, Greg

    2013-01-01

    As an example of the burgeoning importance of stem cell therapy, this past month the California Institute for Regenerative Medicine (CIRM) has approved $70 million to create a new network of stem cell clinical trial centers. Much work in the last decade has been devoted to developing the use of autologous and allogeneic adult stem cell transplants to treat a number of conditions, including heart attack, dementia, wounds, and immune system-related diseases. The standard model teaches us that adult stem cells exists throughout most of the body and provide a means to regenerate and repair most tissues through replication and differentiation. Although we have often witnessed the medical cart placed in front of the scientific horse in the development of stem cell therapies outside of academic circles, great strides have been made, such as the use of purified stem cells1 instead of whole bone marrow transplants in cancer patients, where physicians avoid re-injecting the patients with their own cancer cells.2 We most often think of stem cell therapy acting to regenerate tissue through replication and then differentiation, but recent studies point to the dramatic effects adult stem cells exert in the repair of various tissues through the release of paracrine and autocrine substances, and not simply through differentiation. Indeed, up to 80% of the therapeutic effect of adult stem cells has been shown to be through paracrine mediated actions.3 That is, the collected types of molecules released by the stem cells, called the secretome, or stem cell released molecules (SRM), number in the 100s, including proteins, microRNA, growth factors, antioxidants, proteasomes, and exosomes, and target a multitude of biological pathways through paracrine actions. The composition of the different molecule types in SRM is state dependent, and varies with cell type and conditions such as age and environment. PMID:24567776

  17. Placenta-an alternative source of stem cells

    SciTech Connect

    Matikainen, Tiina; Laine, Jarmo . E-mail: jarmo.laine@bts.redcoss.fi

    2005-09-01

    The two most promising practical applications of human stem cells are cellular replacement therapies in human disease and toxicological screening of candidate drug molecules. Both require a source of human stem cells that can be isolated, purified, expanded in number and differentiated into the cell type of choice in a controlled manner. Currently, uses of both embryonic and adult stem cells are investigated. While embryonic stem cells are pluripotent and can differentiate into any specialised cell type, their use requires establishment of embryonic stem cell lines using the inner cell mass of an early pre-implantation embryo. As the blastocyst is destroyed during the process, ethical issues need to be carefully considered. The use of embryonic stem cells is also limited by the difficulties in growing large numbers of the cells without inducing spontaneous differentiation, and the problems in controlling directed differentiation of the cells. The use of adult stem cells, typically derived from bone marrow, but also from other tissues, is ethically non-controversial but their differentiation potential is more limited than that of the embryonic stem cells. Since human cord blood, umbilical cord, placenta and amnion are normally discarded at birth, they provide an easily accessible alternative source of stem cells. We review the potential and current status of the use of adult stem cells derived from the placenta or umbilical cord in therapeutic and toxicological applications.

  18. Stem cells and combinatorial science.

    PubMed

    Fang, Yue Qin; Wong, Wan Qing; Yap, Yan Wen; Orner, Brendan P

    2007-09-01

    Stem cell-based technologies have the potential to help cure a number of cell degenerative diseases. Combinatorial and high throughput screening techniques could provide tools to control and manipulate the self-renewal and differentiation of stem cells. This review chronicles historic and recent progress in the stem cell field involving both pluripotent and multipotent cells, and it highlights relevant cellular signal transduction pathways. This review further describes screens using libraries of soluble, small-molecule ligands, and arrays of molecules immobilized onto surfaces while proposing future trends in similar studies. It is hoped that by reviewing both the stem cell and the relevant high throughput screening literature, this paper can act as a resource to the combinatorial science community.

  19. The embryonic stem cell test.

    PubMed

    Schulpen, Sjors H W; Piersma, Aldert H

    2013-01-01

    The embryonic stem cell test is an animal-free alternative test method for developmental toxicity. Mouse embryonic stem cells are cultured in a hanging drop method to form embryoid bodies. These embryoid bodies, when plated on tissue culture dishes, differentiate to form contracting myocardial cell foci within 10 days. Inhibition of cardiomyocyte differentiation by test compounds serves as the end point of the assay, as monitored by counting contracting muscle foci under the microscope.

  20. Human Very Small Embryonic-Like Stem Cells Are Present in Normal Peripheral Blood of Young, Middle-Aged, and Aged Subjects.

    PubMed

    Sovalat, Hanna; Scrofani, Maurice; Eidenschenk, Antoinette; Hénon, Philippe

    2016-01-01

    The purpose of our study was to determine whether the number of human very small embryonic-like stem cells (huVSELs) would vary depending on the age of humans. HuVSELs frequency was evaluated into the steady-state (SS) peripheral blood (PB) of healthy volunteers using flow cytometry analysis. Their numbers were compared with volunteers' age. Blood samples were withdrawn from 28 volunteers (age ranging from 20 to 70 years), who were distributed among three groups of age: "young" (mean age, 27.8 years), "middle" (mean age, 49 years), and "older" (mean age, 64.2 years). Comparing the three groups, we did not observe any statistically significant difference in huVSELs numbers between them. The difference in mRNA expression for PSC markers as SSEA-4, Oct-4, Nanog, and Sox2 between the three groups of age was not statistically significant. A similar frequency of huVSELs into the SS-PB of young, middle-aged, and aged subjects may indicate that the VSELs pool persists all along the life as a reserve for tissue repair in case of minor injury and that there is a continuous efflux of these cells from the BM into the PB.

  1. Human Very Small Embryonic-Like Stem Cells Are Present in Normal Peripheral Blood of Young, Middle-Aged, and Aged Subjects

    PubMed Central

    Sovalat, Hanna; Scrofani, Maurice; Eidenschenk, Antoinette; Hénon, Philippe

    2016-01-01

    The purpose of our study was to determine whether the number of human very small embryonic-like stem cells (huVSELs) would vary depending on the age of humans. HuVSELs frequency was evaluated into the steady-state (SS) peripheral blood (PB) of healthy volunteers using flow cytometry analysis. Their numbers were compared with volunteers' age. Blood samples were withdrawn from 28 volunteers (age ranging from 20 to 70 years), who were distributed among three groups of age: “young” (mean age, 27.8 years), “middle” (mean age, 49 years), and “older” (mean age, 64.2 years). Comparing the three groups, we did not observe any statistically significant difference in huVSELs numbers between them. The difference in mRNA expression for PSC markers as SSEA-4, Oct-4, Nanog, and Sox2 between the three groups of age was not statistically significant. A similar frequency of huVSELs into the SS-PB of young, middle-aged, and aged subjects may indicate that the VSELs pool persists all along the life as a reserve for tissue repair in case of minor injury and that there is a continuous efflux of these cells from the BM into the PB. PMID:26633977

  2. Mesenchymal Stem Cells as Feeder Cells for Pancreatic Islet Transplants

    PubMed Central

    Sordi, Valeria; Piemonti, Lorenzo

    2010-01-01

    Allogeneic islet transplantation serves as a source of insulin-secreting beta-cells for the maintenance of normal glucose levels and treatment of diabetes. However, limited availability of islets, high rates of islet graft failure, and the need for life-long non-specific immunosuppressive therapy are major obstacles to the widespread application of this therapeutic approach. To overcome these problems, pancreatic islet transplantation was recently suggested as a potential target of the "therapeutic plasticity" of adult stem cells. In fact, new results suggest that stem/precursor cells, and mesenchymal stem cells in particular, co-transplanted with islets can promote tissue engraftment and beta-cell survival via bystander mechanisms, mainly exerted by creating a milieu of cytoprotective and immunomodulatory molecules. This evidence consistently challenges the limited view that stem/precursor cells work exclusively through beta-cell replacement in diabetes therapy. It proposes that stem cells also act as "feeder" cells for islets, and supporter of graft protection, tissue revascularization, and immune acceptance. This article reviews the experience of using stem cell co-transplantation as strategy to improve islet transplantation. It highlights that comprehension of the mechanisms involved will help to identify new molecular targets and promote development of new pharmacological strategies to treat type 1 and type 2 diabetes patients. PMID:21060972

  3. Mesenchymal stem cells as feeder cells for pancreatic islet transplants.

    PubMed

    Sordi, Valeria; Piemonti, Lorenzo

    2010-01-01

    Allogeneic islet transplantation serves as a source of insulin-secreting beta-cells for the maintenance of normal glucose levels and treatment of diabetes. However, limited availability of islets, high rates of islet graft failure, and the need for life-long non-specific immunosuppressive therapy are major obstacles to the widespread application of this therapeutic approach. To overcome these problems, pancreatic islet transplantation was recently suggested as a potential target of the "therapeutic plasticity" of adult stem cells. In fact, new results suggest that stem/precursor cells, and mesenchymal stem cells in particular, co-transplanted with islets can promote tissue engraftment and beta-cell survival via bystander mechanisms, mainly exerted by creating a milieu of cytoprotective and immunomodulatory molecules. This evidence consistently challenges the limited view that stem/precursor cells work exclusively through beta-cell replacement in diabetes therapy. It proposes that stem cells also act as "feeder" cells for islets, and supporter of graft protection, tissue revascularization, and immune acceptance. This article reviews the experience of using stem cell co-transplantation as strategy to improve islet transplantation. It highlights that comprehension of the mechanisms involved will help to identify new molecular targets and promote development of new pharmacological strategies to treat type 1 and type 2 diabetes patients. PMID:21060972

  4. Stem cell marker upregulation in normal cutaneous vessels following pulsed-dye laser exposure and its abrogation by concurrent rapamycin administration: implications for treatment of port-wine stain birthmarks

    PubMed Central

    Loewe, Robert; Oble, Darryl A.; Valero, Teresa; Zukerberg, Lawrence; Mihm, Martin C.; Nelson, J. Stuart

    2011-01-01

    Port-wine stains (PWS) represent a group of vascular malformations that are usually accompanied by psychological distress for affected patients, often reflected in high treatment demand. Although the pulsed-dye laser (PDL) was established as standard therapy for PWS more than a decade ago, therapeutic outcome may be unsatisfactory. One of the main drawbacks to successful PDL therapy is PWS revascularization shortly after laser exposure. Therefore, inhibition of revascularization should improve therapeutic outcome of PDL therapy. In this study, we first evaluated the effects of various light energies on normal cutaneous vessels over a period of 14 days, particularly the proliferation and stem cell marker expression of dermal endothelial cells, which were found to be highest 8 days following laser exposure. We found that PDL exposure induced dose-dependent damage of dermal vessels up to energy densities of 6 J/cm2, above which no increase in PDL-induced effects were observed with the energies employed in this study. In dermal endothelial cells of PDL-exposed skin, we found strong expression of the proliferation marker Ki-67 as well as the stem cell marker nestin but not other stem cell markers such as CD133 and CD166. The influence of rapamycin (RPM), used as an adjuvant to PDL exposure, was also investigated. RPM administration reduced Ki-67 and nestin expression in dermal endothelial cells and increased PDL-induced destruction of dermal vessels, indicating that the use of RPM after PDL exposure may be an interesting new approach for prolonging and improving PWS laser therapeutic outcome. PMID:20482679

  5. Harvesting dental stem cells - Overview

    PubMed Central

    Sunil, P. M.; Manikandan, Ramanathan; Muthumurugan; Yoithapprabhunath, Thukanayakanpalayam Ragunathan; Sivakumar, Muniapillai

    2015-01-01

    Dental stem cells have recently become one of the widely researched areas in dentistry. Ever since the identification of stem cells from various dental tissues like deciduous teeth, dental papilla, periodontal ligament and third molars, storing them for future use for various clinical applications was being explored. Dental stem cells were harvested and isolated using various techniques by different investigators and laboratories. This article explains the technical aspects of preparing the patient, atraumatic and aseptic removal of the tooth and its safe transportation and preservation for future expansion. PMID:26538883

  6. Stem cells, dot-com.

    PubMed

    Liang, Bryan A; Mackey, Tim K

    2012-09-12

    Direct-to-consumer (DTC) advertising of suspect goods and services has burgeoned because of the Internet. Despite very limited approval for use, DTC stem cell-marketed "treatments" have emerged for an array of conditions, creating global public health and safety risks. However, it remains unclear whether such use of stem cells is subject to drugs or biologics regulations. To address this gap, regulatory agencies should be given clear authority, and the international community should create a framework for appropriate stem cell use. In addition, consumer protection laws should be used to scrutinize providers.

  7. Drosophila's contribution to stem cell research

    PubMed Central

    Singh, Gyanesh

    2016-01-01

    The discovery of Drosophila stem cells with striking similarities to mammalian stem cells has brought new hope for stem cell research. Recent developments in Drosophila stem cell research is bringing wider opportunities for contemporary stem cell biologists. In this regard, Drosophila germ cells are becoming a popular model of stem cell research. In several cases, genes that controlled Drosophila stem cells were later discovered to have functional homologs in mammalian stem cells. Like mammals, Drosophila germline stem cells (GSCs) are controlled by both intrinsic as well as external signals. Inside the Drosophila testes, germline and somatic stem cells form a cluster of cells (the hub). Hub cells depend on JAK-STAT signaling, and, in absence of this signal, they do not self-renew. In Drosophila, significant changes occur within the stem cell niche that contributes to a decline in stem cell number over time. In case of aging Drosophila, somatic niche cells show reduced DE-cadherin and unpaired (Upd) proteins. Unpaired proteins are known to directly decrease stem cell number within the niches, and, overexpression of upd within niche cells restored GSCs in older males also . Stem cells in the midgut of Drosophila are also very promising. Reduced Notch signaling was found to increase the number of midgut progenitor cells. On the other hand, activation of the Notch pathway decreased proliferation of these cells. Further research in this area should lead to the discovery of additional factors that regulate stem and progenitor cells in Drosophila. PMID:26180635

  8. Drosophila's contribution to stem cell research.

    PubMed

    Singh, Gyanesh

    2015-01-01

    The discovery of Drosophila stem cells with striking similarities to mammalian stem cells has brought new hope for stem cell research. Recent developments in Drosophila stem cell research is bringing wider opportunities for contemporary stem cell biologists. In this regard, Drosophila germ cells are becoming a popular model of stem cell research. In several cases, genes that controlled Drosophila stem cells were later discovered to have functional homologs in mammalian stem cells. Like mammals, Drosophila germline stem cells (GSCs) are controlled by both intrinsic as well as external signals. Inside the Drosophila testes, germline and somatic stem cells form a cluster of cells (the hub). Hub cells depend on JAK-STAT signaling, and, in absence of this signal, they do not self-renew. In Drosophila, significant changes occur within the stem cell niche that contributes to a decline in stem cell number over time. In case of aging Drosophila, somatic niche cells show reduced DE-cadherin and unpaired (Upd) proteins. Unpaired proteins are known to directly decrease stem cell number within the niches, and, overexpression of upd within niche cells restored GSCs in older males also . Stem cells in the midgut of Drosophila are also very promising. Reduced Notch signaling was found to increase the number of midgut progenitor cells. On the other hand, activation of the Notch pathway decreased proliferation of these cells. Further research in this area should lead to the discovery of additional factors that regulate stem and progenitor cells in Drosophila. PMID:26180635

  9. Advances in stem cell therapy.

    PubMed

    Pérez López, Silvia; Otero Hernández, Jesús

    2012-01-01

    Since the beginning of stem cell biology, considerable effort has been focused in the translation of scientific insights into new therapies. Cell-based assays represent a new strategy for organ and tissue repair in several pathologies. Moreover, alternative treatment strategies are urgently needed due to donor organ shortage that costs many lives every year and results in lifelong immunosuppression. At the moment, only the use of hematopoietic stem cells is considered as the standard for the treatment of malignant and genetic bone marrow disorders, being all other stem cell applications highly experimental. The present chapter tries to summarize some ongoing approaches of stem cell regenerative medicine and also introduces recent findings from published studies and trials conducted in various tissues such as skeletal muscle, liver and lung.

  10. Diabetes and stem cell function.

    PubMed

    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.

  11. Stem cells in cardiac repair.

    PubMed

    Henning, Robert J

    2011-01-01

    Myocardial infarction is the leading cause of death among people in industrialized nations. Although the heart has some ability to regenerate after infarction, myocardial restoration is inadequate. Consequently, investigators are currently exploring the use of human embryonic stem cells (hESCs), skeletal myoblasts and adult bone marrow stem cells to limit infarct size. hESCs are pluripotent cells that can regenerate myocardium in infarcted hearts, attenuate heart remodeling and contribute to left ventricle (LV) systolic force development. Since hESCs can form heart teratomas, investigators are differentiating hESCs toward cardiac progenitor cells prior to transplantation into hearts. Large quantities of hESCs cardiac progenitor cells, however, must be generated, immune rejection must be prevented and grafts must survive over the long term to significantly improve myocardial performance. Transplanted autologous skeletal myoblasts can survive in infarcted myocardium in small numbers, proliferate, differentiate into skeletal myofibers and increase the LV ejection fraction. These cells, however, do not form electromechanical connections with host cardiomyocytes. Consequently, electrical re-entry can occur and cause cardiac arrhythmias. Autologous bone marrow mononuclear cells contain hematopoietic and mesenchymal stem cells. In several meta-analyses, patients with coronary disease who received autologous bone marrow cells by intracoronary injection show significant 3.7% (range: 1.9-5.4%) increases in LV ejection fraction, decreases in LV end-systolic volume of -4.8 ml (range: -1.4 to -8.2 ml) and reductions in infarct size of 5.5% (-1.9 to -9.1%), without experiencing arrhythmias. Bone marrow cells appear to release biologically active factors that limit myocardial damage. Unfortunately, bone marrow cells from patients with chronic diseases propagate poorly and can die prematurely. Substantial challenges must be addressed and resolved to advance the use of stem cells

  12. Epigenetic Loss of MLH1 Expression in Normal Human Hematopoietic Stem Cell Clones is Defined by the Promoter CpG Methylation Pattern Observed by High-Throughput Methylation Specific Sequencing

    PubMed Central

    Kenyon, Jonathan; Nickel-Meester, Gabrielle; Qing, Yulan; Santos-Guasch, Gabriela; Drake, Ellen; PingfuFu; Sun, Shuying; Bai, Xiaodong; Wald, David; Arts, Eric; Gerson, Stanton L.

    2016-01-01

    Normal human hematopoietic stem and progenitor cells (HPC) lose expression of MLH1, an important mismatch repair (MMR) pathway gene, with age. Loss of MMR leads to replication dependent mutational events and microsatellite instability observed in secondary acute myelogenous leukemia and other hematologic malignancies. Epigenetic CpG methylation upstream of the MLH1 promoter is a contributing factor to acquired loss of MLH1 expression in tumors of the epithelia and proximal mucosa. Using single molecule high-throughput bisulfite sequencing we have characterized the CpG methylation landscape from −938 to −337 bp upstream of the MLH1 transcriptional start site (position +0), from 30 hematopoietic colony forming cell clones (CFC) either expressing or not expressing MLH1. We identify a correlation between MLH1 promoter methylation and loss of MLH1 expression. Additionally, using the CpG site methylation frequencies obtained in this study we were able to generate a classification algorithm capable of sorting the expressing and non-expressing CFC. Thus, as has been previously described for many tumor cell types, we report for the first time a correlation between the loss of MLH1 expression and increased MLH1 promoter methylation in CFC derived from CD34+ selected hematopoietic stem and progenitor cells. PMID:27570841

  13. Intestinal Stem Cells: Got Calcium?

    PubMed

    Nászai, Máté; Cordero, Julia B

    2016-02-01

    Calcium ions are well-known intracellular signalling molecules. A new study identifies local cytoplasmic calcium as a central integrator of metabolic and proliferative signals in Drosophila intestinal stem cells. PMID:26859268

  14. Stem cell potential of the mammalian gonad

    PubMed Central

    Liu, Chia-Feng; Barsoum, Ivraym; Gupta, Rupesh; Hofmann, Marie-Claude; Yao, Humphrey Hung-Chang

    2010-01-01

    Stem cells have enormous potential for therapeutic application because of their ability to self-renew and differentiate into different cell types. Gonads, which consist of somatic cells and germ cells, are the only organs capable of transmitting genetic materials to the offspring. Germ-line stem cells and somatic stem cells have been found in the testis; however, the presence of stem cells in the ovary remains controversial. In this review, we discuss studies focusing on whether stem cell properties are present in the different cell types of male and female gonads and their implications on stem cell research. PMID:19482665

  15. Pancreatic stem cells remain unresolved.

    PubMed

    Jiang, Fang-Xu; Morahan, Grant

    2014-12-01

    Diabetes mellitus is caused by absolute (type 1) or relative (type 2) deficiency of insulin-secreting islet β cells. An ideal treatment of diabetes would, therefore, be to replace the lost or deficient β cells, by transplantation of donated islets or differentiated endocrine cells or by regeneration of endogenous islet cells. Due to their ability of unlimited proliferation and differentiation into all functional lineages in our body, including β cells, embryonic stem cells and induced pluripotent stem cells are ideally placed as cell sources for a diabetic transplantation therapy. Unfortunately, the inability to generate functional differentiated islet cells from pluripotent stem cells and the poor availability of donor islets have severely restricted the broad clinical use of the replacement therapy. Therefore, endogenous sources that can be directed to becoming insulin-secreting cells are actively sought after. In particular, any cell types in the developing or adult pancreas that may act as pancreatic stem cells (PSC) would provide an alternative renewable source for endogenous regeneration. In this review, we will summarize the latest progress and knowledge of such PSC, and discuss ways that facilitate the future development of this often controversial, but crucial research.

  16. Stem cell applications in diabetes.

    PubMed

    Noguchi, Hirofumi

    2012-01-01

    Diabetes mellitus is a devastating disease and the World Health Organization (WHO) expects that the number of diabetic patients will increase to 300 million by the year 2025. Patients with diabetes experience decreased insulin secretion that is linked to a significant reduction in the number of islet cells. Type 1 diabetes is characterized by the selective destruction of pancreatic β cells caused by an autoimmune attack. Type 2 diabetes is a more complex pathology that, in addition to β cell loss caused by apoptotic programs, includes β cell de-differentiation and peripheric insulin resistance. The success achieved over the last few years with islet transplantation suggests that diabetes can be cured by the replenishment of deficient β cells. These observations are proof of the concept and have intensified interest in treating diabetes or other diseases not only by cell transplantation but also by stem cells. An increasing body of evidence indicates that, in addition to embryonic stem cells, several potential adult stem/progenitor cells derived from the pancreas, liver, spleen, and bone marrow could differentiate into insulin-producing cells in vitro or in vivo. However, significant controversy currently exists in this field. Pharmacological approaches aimed at stimulating the in vivo/ex vivo regeneration of β cells have been proposed as a way of augmenting islet cell mass. Overexpression of embryonic transcription factors in stem cells could efficiently induce their differentiation into insulin-expressing cells. A new technology, known as protein transduction, facilitates the differentiation of stem cells into insulin-producing cells. Recent progress in the search for new sources of β cells has opened up several possibilities for the development of new treatments for diabetes.

  17. Stacking the DEK: From chromatin topology to cancer stem cells

    PubMed Central

    Privette Vinnedge, Lisa M.; Kappes, Ferdinand; Nassar, Nicolas; Wells, Susanne I.

    2013-01-01

    Stem cells are essential for development and tissue maintenance and display molecular markers and functions distinct from those of differentiated cell types in a given tissue. Malignant cells that exhibit stem cell-like activities have been detected in many types of cancers and have been implicated in cancer recurrence and drug resistance. Normal stem cells and cancer stem cells have striking commonalities, including shared cell surface markers and signal transduction pathways responsible for regulating quiescence vs. proliferation, self-renewal, pluripotency and differentiation. As the search continues for markers that distinguish between stem cells, progenitor cells and cancer stem cells, growing evidence suggests that a unique chromatin-associated protein called DEK may confer stem cell-like qualities. Here, we briefly describe current knowledge regarding stem and progenitor cells. We then focus on new findings that implicate DEK as a regulator of stem and progenitor cell qualities, potentially through its unusual functions in the regulation of local or global chromatin organization. PMID:23255114

  18. The biology of melanocyte and melanocyte stem cell.

    PubMed

    Li, Ang

    2014-04-01

    The melanocyte stem cells of the hair follicle provide an attractive system for the study of the stem cells. Successful regeneration of a functional organ relies on the organized and timely orchestration of molecular events among distinct stem/progenitor cell populations. The stem cells are regulated by communication with their specialized microenvironment known as the niche. Despite remarkable progress in understanding stem cell-intrinsic behavior, the molecular nature of the extrinsic factors provided to the stem cells by the niche microenvironment remains poorly understood. In this regard, the bulge niche of the mammalian hair follicle offers an excellent model for study. It holds two resident populations of SCs: epidermal stem cells and melanocyte stem cells. While their behavior is tightly coordinated, very little of the crosstalk involved is known. This review summarized the recent development in trying to understand the regulation of melanocyte and melanocyte stem cells. A better understanding of the normal regulation and behaviors of the melanocytes and the melanocyte stem cells will help to improve the clinical applications in regenerative medicine, cancer therapy, and aging.

  19. Dormancy activation mechanism of tracheal stem cells

    PubMed Central

    Li, Xin; Xu, Jing-xian; Jia, Xin-Shan; Li, Wen-ya; Han, Yi-chen; Wang, En-hua; Li, Fang

    2016-01-01

    Accurate markers and molecular mechanisms of stem cell dormancy and activation are poorly understood. In this study, the anti-cancer drug, 5-fluorouracil, was used to selectively kill proliferating cells of human bronchial epithelial (HBE) cell line. This method can enrich and purify stem cell population. The dormant versus active status of stem cells was determined by phosphorylation of RNAp II Ser2. The surviving stem cells were cultured to form stem cell spheres expressing stem cell markers and transplanted into nude mice to form a teratoma. The results demonstrated the properties of stem cells and potential for multi-directional differentiation. Bisulfite sequencing polymerase chain reaction showed that demethylation of the Sox2 promoter by 5-FU resulted in Sox2 expression in the dormant stem cells. This study shows that the dormancy and activation of HBE stem cells is closely related to epigenetic modification. PMID:27009861

  20. Stem cell regulation: Implications when differentiated cells regulate symmetric stem cell division.

    PubMed

    Høyem, Marte Rørvik; Måløy, Frode; Jakobsen, Per; Brandsdal, Bjørn Olav

    2015-09-01

    We use a mathematical model to show that if symmetric stem cell division is regulated by differentiated cells, then changes in the population dynamics of the differentiated cells can lead to changes in the population dynamics of the stem cells. More precisely, the relative fitness of the stem cells can be affected by modifying the death rate of the differentiated cells. This result is interesting because stem cells are less sensitive than differentiated cells to environmental factors, such as medical therapy. Our result implies that stem cells can be manipulated indirectly by medical treatments that target the differentiated cells. PMID:25997796

  1. Engineering stem cell niches in bioreactors

    PubMed Central

    Liu, Meimei; Liu, Ning; Zang, Ru; Li, Yan; Yang, Shang-Tian

    2013-01-01

    Stem cells, including embryonic stem cells, induced pluripotent stem cells, mesenchymal stem cells and amniotic fluid stem cells have the potential to be expanded and differentiated into various cell types in the body. Efficient differentiation of stem cells with the desired tissue-specific function is critical for stem cell-based cell therapy, tissue engineering, drug discovery and disease modeling. Bioreactors provide a great platform to regulate the stem cell microenvironment, known as “niches”, to impact stem cell fate decision. The niche factors include the regulatory factors such as oxygen, extracellular matrix (synthetic and decellularized), paracrine/autocrine signaling and physical forces (i.e., mechanical force, electrical force and flow shear). The use of novel bioreactors with precise control and recapitulation of niche factors through modulating reactor operation parameters can enable efficient stem cell expansion and differentiation. Recently, the development of microfluidic devices and microbioreactors also provides powerful tools to manipulate the stem cell microenvironment by adjusting flow rate and cytokine gradients. In general, bioreactor engineering can be used to better modulate stem cell niches critical for stem cell expansion, differentiation and applications as novel cell-based biomedicines. This paper reviews important factors that can be more precisely controlled in bioreactors and their effects on stem cell engineering. PMID:24179601

  2. Facultative stem cells in liver and pancreas: fact and fancy.

    PubMed

    Yanger, Kilangsungla; Stanger, Ben Z

    2011-03-01

    Tissue turnover is a regular feature of higher eukaryotes, either as part of normal wear and tear (homeostasis) or in response to injury (regeneration). Cell replacement is achieved either through replication of existing cells or differentiation from a self-renewing pool of stem cells. The major distinction regards cellular potential, because stem cells by definition have a capacity to differentiate, while replication implies that cells adopt a single fate under physiologic conditions. A hybrid model, the facultative stem cell (FSC) model, posits that tissues contain cells that normally exhibit unipotency but have the capacity to function as stem cells upon injury. The FSC paradigm is well established in urodele amphibians, but the nature and role of FSCs in mammals is less defined. Here, we review the evidence for FSCs in two mammalian organs, the liver and the pancreas, and discuss alternative models that could account for regeneration in these organs.

  3. Generation of insulin-producing cells from stem cells.

    PubMed

    Soria, Bernat; Roche, Enrique; Reig, Juan A; Martin, Franz

    2005-01-01

    Islet transplantation as a potential treatment for diabetes will always be limited mainly because of the difficulty in obtaining sufficiently large numbers of purified islets from cadaveric donors. One alternative to organ or tissue transplantation is the use of a renewable source of cells. Stem cells are clonogenic cells capable of both self-renewal and multilineage differentiation. Therefore, these cells have the potential to proliferate and differentiate into any type of cell and to be genetically modified in vitro, thus providing cells which can be isolated and used for transplantation. Moreover, these derived cells have proven to be useful in different animal models. In this regard, insulin-secreting cells derived from mouse embryonic stem cells normalize blood glucose when transplanted into streptozotocin-induced diabetic animals. Using a combination of several differentiation methods and a 'cell trapping' system, we have obtained insulin-secreting cells from undifferentiated embryonic stem cells. The construct used allows the expression of a neomycin selection system under the control of the regulatory regions of insulin gene and other beta cell genes, such as Nkx6.1. Transplanted animals correct hyperglycaemia within 1 week and restore body weight in four weeks. Graft removal rescued the diabetic condition. Glucose tolerance test (IPGTT) and blood glucose normalization after a challenge meal was similar in control and in transplanted animals. This approach opens new possibilities for tissue transplantation in the treatment of type 1 and 2 diabetes.

  4. Dental Stem Cell in Tooth Development and Advances of Adult Dental Stem Cell in Regenerative Therapies.

    PubMed

    Tan, Jiali; Xu, Xin; Lin, Jiong; Fan, Li; Zheng, Yuting; Kuang, Wei

    2015-01-01

    Stem cell-based therapies are considered as a promising treatment for many clinical usage such as tooth regeneration, bone repairation, spinal cord injury, and so on. However, the ideal stem cell for stem cell-based therapy still remains to be elucidated. In the past decades, several types of stem cells have been isolated from teeth, including dental pulp stem cells (DPSCs), stem cells from human exfoliated deciduous teeth (SHED), periodontal ligament stem cells (PDLSCs), dental follicle progenitor stem cells (DFPCs) and stem cells from apical papilla (SCAP), which may be a good source for stem cell-based therapy in certain disease, especially when they origin from neural crest is considered. In this review, the specific characteristics and advantages of the adult dental stem cell population will be summarized and the molecular mechanisms of the differentiation of dental stem cell during tooth development will be also discussed.

  5. Stem cells and kidney regeneration.

    PubMed

    Chou, Yu-Hsiang; Pan, Szu-Yu; Yang, Chian-Huei; Lin, Shuei-Liong

    2014-04-01

    Kidney disease is an escalating burden all over the world. In addition to preventing kidney injury, regenerating damaged renal tissue is as important as to retard the progression of chronic kidney disease to end stage renal disease. Although the kidney is a delicate organ and has only limited regenerative capacity compared to the other organs, an increasing understanding of renal development and renal reprogramming has kindled the prospects of regenerative options for kidney disease. Here, we will review the advances in the kidney regeneration including the manipulation of renal tubular cells, fibroblasts, endothelial cells, and macrophages in renal disease. Several types of stem cells, such as bone marrow-derived cells, adipocyte-derived mesenchymal stem cells, embryonic stem cells, and induced pluripotent stem cells are also applied for renal regeneration. Endogenous or lineage reprogrammed renal progenitor cells represent an attractive possibility for differentiation into multiple renal cell types. Angiogenesis can ameliorate hypoxia and renal fibrosis. Based on these studies and knowledge, we hope to innovate more reliable pharmacological or biotechnical methods for kidney regeneration medicine.

  6. Stem cells: a new paradigm in medical therapeutics.

    PubMed

    Mankikar, Sadanand D

    2010-01-01

    Even though the stem cells have been studied for decades, only during the past few years has there been an overwhelming proliferation of publications covering isolation, cultivation and utilization of the body's master cells. This paper attempts to summarize the recent studies in the field of stem cells. A number of studies have reported the existence of multipotent stem cells in the cord, cord blood, placenta, bone marrow, brain, heart, teeth, skin, liver, hair follicles and many other tissues and organs, giving rise to cell types other than their tissue of origin. Increased therapeutic use of stem cells has resulted in scientific methods of collection, testing, processing and storage of these cells, with minimal cell damage and differentiation. Cell expansion, bioreactors and tissue engineering are employed extensively to improve the cell dose and outcome. Stem cell infusion, transplantation and implantation are accepted curative therapies for many malignant and non-malignant conditions. Stem cell therapies also provide alternative solutions for the repair and regeneration of various tissues and organs. There has been a dramatic improvement in the understanding of immunosuppressive properties of stem cells on various immune cell types. Stem cells are found to secrete angiogenic cytokines that increase neovascularization. They bring the promise of curing a disease state as these cells normally regenerate tissues in a healthy organism. Stem cell transplantation, in isolation or in combination with other procedures, has been found to be effective. Stem cell therapy is also seen as a possible alternative for the treatment of different diseases such as juvenile diabetes, amyotrophic lateral sclerosis, cerebral palsy, stroke, spinal cord injury and Parkinson's disease. Regenerative medicine using human stem cells is one of the new and promising fields for treating various intractable diseases and damaged organs. PMID:21395520

  7. Immunohistological techniques for studying the Drosophila male germline stem cell.

    PubMed

    Singh, Shree Ram; Hou, Steven X

    2008-01-01

    Stem cells are undifferentiated cells that have a remarkable ability to self-renew and produce differentiated cells that support normal development and tissue homeostasis. This unique capacity makes stem cells a powerful tool for future regenerative medicine and gene therapy. Accumulative evidence suggests that stem cell self-renewal or differentiation is controlled by both intrinsic and extrinsic factors, and that deregulation of stem cell behavior results in cancer formation, tissue degeneration, and premature aging. The Drosophila testis provides an excellent in vivo model for studying and understanding the fundamental cellular and molecular mechanisms controlling stem cell behavior and the relationship between niches and stem cells. At the tip of the Drosophila testes, germline stem cells (GSCs) and somatic stem cells (SSCs) contact each other and share common niches (known as a hub) to maintain spermatogenesis. Signaling pathways, such as the Janus kinase (JAK)/signal transducer and activator of transcription (STAT), bone morphogenetic protein (BMP), ras-associated protein-guanine nucleotide exchange factor for small GTPase (Rap-GEF), and epidermal growth factor receptor (EGFR)/mitogen-activated protein kinase (MAPK), are known to regulate self-renewal or differentiation of Drosophila male germline stem cells. We describe the detailed in vivo immunohistological protocols that mark GSCs, SSCs, and their progeny in Drosophila testes. PMID:18370050

  8. Pluripotent stem cells from germ cells.

    PubMed

    Kerr, Candace L; Shamblott, Michael J; Gearhart, John D

    2006-01-01

    To date, stem cells have been derived from three sources of germ cells. These include embryonic germ cells (EGCs), embryonal carcinoma cells (ECCs), and multipotent germ line stem cells (GSCs). EGCs are derived from primordial germ cells that arise in the late embryonic and early fetal period of development. ECCs are derived from adult testicular tumors whereas GSCs have been derived by culturing spermatogonial stem cells from mouse neonates and adults. For each of these lines, their pluripotency has been demonstrated by their ability to differentiate into cell types derived from the three germ layers in vitro and in vivo and in chimeric animals, including germ line transmission. These germ line-derived stem cells have been generated from many species including human, mice, porcine, and chicken albeit with only slight modifications. This chapter describes general considerations regarding critical aspects of their derivation compared with their counterpart, embryonic stem cells (ESCs). Detailed protocols for EGC derivation and maintenance from human and mouse primordial germ cells (PGCs) will be presented.

  9. DNA methylation and hydroxymethylation in stem cells.

    PubMed

    Cheng, Ying; Xie, Nina; Jin, Peng; Wang, Tao

    2015-06-01

    In mammals, DNA methylation and hydroxymethylation are specific epigenetic mechanisms that can contribute to the regulation of gene expression and cellular functions. DNA methylation is important for the function of embryonic stem cells and adult stem cells (such as haematopoietic stem cells, neural stem cells and germline stem cells), and changes in DNA methylation patterns are essential for successful nuclear reprogramming. In the past several years, the rediscovery of hydroxymethylation and the TET enzymes expanded our insights tremendously and uncovered more dynamic aspects of cytosine methylation regulation. Here, we review the current knowledge and highlight the most recent advances in DNA methylation and hydroxymethylation in embryonic stem cells, induced pluripotent stem cells and several well-studied adult stems cells. Our current understanding of stem cell epigenetics and new advances in the field will undoubtedly stimulate further clinical applications of regenerative medicine in the future.

  10. Stem cells' exodus: a journey to immortality.

    PubMed

    Zhou, Yi; Lewallen, Michelle; Xie, Ting

    2013-01-28

    Stem cell niches provide a regulatory microenvironment that retains stem cells and promotes self-renewal. Recently in Developmental Cell, Rinkevich et al. (2013) showed that cell islands (CIs) of Botryllus schlosseri, a colonial chordate, provide niches for maintaining cycling stem cells that migrate from degenerated CIs to newly formed buds.

  11. Human stem cell ethics: beyond the embryo.

    PubMed

    Sugarman, Jeremy

    2008-06-01

    Human embryonic stem cell research has elicited powerful debates about the morality of destroying human embryos. However, there are important ethical issues related to stem cell research that are unrelated to embryo destruction. These include particular issues involving different types of cells used, the procurement of such cells, in vivo use of stem cells, intellectual property, and conflicts of interest.

  12. Stem-cell ecology and stem cells in motion

    PubMed Central

    Scadden, David T.

    2008-01-01

    This review highlights major scientific developments over the past 50 years or so in concepts related to stem-cell ecology and to stem cells in motion. Many thorough and eloquent reviews have been presented in the last 5 years updating progress in these issues. Some paradigms have been challenged, others validated, or new ones brought to light. In the present review, we will confine our remarks to the historical development of progress. In doing so, we will refrain from a detailed analysis of controversial data, emphasizing instead widely accepted views and some challenging novel ones. PMID:18398055

  13. Reprogramming stem cells is a microenvironmental task

    SciTech Connect

    Bissell, Mina J; Inman, Jamie

    2008-10-14

    That tumor cells for all practical purposes are unstable and plastic could be expected. However, the astonishing ability of the nuclei from cells of normal adult tissues to be reprogrammed - given the right embryonic context - found its final truth even for mammals in the experiments that allowed engineering Dolly (1). The landmark experiments showed that nuclei originating from cells of frozen mammary tissues were capable of being reprogrammed by the embryonic cytoplasm and its microenvironment to produce a normal sheep. The rest is history. However, whether microenvironments other than those of the embryos can also reprogram adult cells of different tissue origins still containing their cytoplasm is of obvious interest. In this issue of PNAS, the laboratory of Gilbert Smith (2) reports on how the mammary gland microenvironment can reprogram both embryonic and adult stem neuronal cells. The work is a follow-up to their previous report on testis stem cells that were reprogrammed by the mammary microenvironment (3). They demonstrated that cells isolated from the seminiferous tubules of the mature testis, mixed with normal mammary epithelial cells, contributed a sizable number of epithelial progeny to normal mammary outgrowths in transplanted mammary fat pads. However, in those experiments they were unable to distinguish which subpopulation of the testis cells contributed progeny to the mammary epithelial tree. The current work adds new, compelling, and provocative information to our understanding of stem cell plasticity. Booth et al. (2) use neuronal stem cells (NSCs) isolated from WAP-cre/R26R mice combined with unlabeled mammary epithelial cells that subsequently are implanted in cleared mammary fat pads. In this new microenvironment, the NSCs that are incorporated into the branching mammary tree make chimeric glands (Fig. 1) that remarkably can also express the milk protein {beta}-casein, progesterone receptor, and estrogen receptor {alpha}. Remarkably, the

  14. Introduction to stem cells and regenerative medicine.

    PubMed

    Kolios, George; Moodley, Yuben

    2013-01-01

    Stem cells are a population of undifferentiated cells characterized by the ability to extensively proliferate (self-renewal), usually arise from a single cell (clonal), and differentiate into different types of cells and tissue (potent). There are several sources of stem cells with varying potencies. Pluripotent cells are embryonic stem cells derived from the inner cell mass of the embryo and induced pluripotent cells are formed following reprogramming of somatic cells. Pluripotent cells can differentiate into tissue from all 3 germ layers (endoderm, mesoderm, and ectoderm). Multipotent stem cells may differentiate into tissue derived from a single germ layer such as mesenchymal stem cells which form adipose tissue, bone, and cartilage. Tissue-resident stem cells are oligopotent since they can form terminally differentiated cells of a specific tissue. Stem cells can be used in cellular therapy to replace damaged cells or to regenerate organs. In addition, stem cells have expanded our understanding of development as well as the pathogenesis of disease. Disease-specific cell lines can also be propagated and used in drug development. Despite the significant advances in stem cell biology, issues such as ethical controversies with embryonic stem cells, tumor formation, and rejection limit their utility. However, many of these limitations are being bypassed and this could lead to major advances in the management of disease. This review is an introduction to the world of stem cells and discusses their definition, origin, and classification, as well as applications of these cells in regenerative medicine.

  15. Common stemness regulators of embryonic and cancer stem cells.

    PubMed

    Hadjimichael, Christiana; Chanoumidou, Konstantina; Papadopoulou, Natalia; Arampatzi, Panagiota; Papamatheakis, Joseph; Kretsovali, Androniki

    2015-10-26

    Pluripotency of embryonic stem cells (ESCs) and induced pluripotent stem cells is regulated by a well characterized gene transcription circuitry. The circuitry is assembled by ESC specific transcription factors, signal transducing molecules and epigenetic regulators. Growing understanding of stem-like cells, albeit of more complex phenotypes, present in tumors (cancer stem cells), provides a common conceptual and research framework for basic and applied stem cell biology. In this review, we highlight current results on biomarkers, gene signatures, signaling pathways and epigenetic regulators that are common in embryonic and cancer stem cells. We discuss their role in determining the cell phenotype and finally, their potential use to design next generation biological and pharmaceutical approaches for regenerative medicine and cancer therapies.

  16. Common stemness regulators of embryonic and cancer stem cells

    PubMed Central

    Hadjimichael, Christiana; Chanoumidou, Konstantina; Papadopoulou, Natalia; Arampatzi, Panagiota; Papamatheakis, Joseph; Kretsovali, Androniki

    2015-01-01

    Pluripotency of embryonic stem cells (ESCs) and induced pluripotent stem cells is regulated by a well characterized gene transcription circuitry. The circuitry is assembled by ESC specific transcription factors, signal transducing molecules and epigenetic regulators. Growing understanding of stem-like cells, albeit of more complex phenotypes, present in tumors (cancer stem cells), provides a common conceptual and research framework for basic and applied stem cell biology. In this review, we highlight current results on biomarkers, gene signatures, signaling pathways and epigenetic regulators that are common in embryonic and cancer stem cells. We discuss their role in determining the cell phenotype and finally, their potential use to design next generation biological and pharmaceutical approaches for regenerative medicine and cancer therapies. PMID:26516408

  17. Bone marrow stem cell as a potential treatment for diabetes.

    PubMed

    Li, Ming; Ikehara, Susumu

    2013-01-01

    Diabetes mellitus (DM) is a group of metabolic diseases in which a person has high blood glucose levels resulting from defects in insulin secretion and insulin action. The chronic hyperglycemia damages the eyes, kidneys, nerves, heart, and blood vessels. Curative therapies mainly include diet, insulin, and oral hypoglycemic agents. However, these therapies fail to maintain blood glucose levels in the normal range all the time. Although pancreas or islet-cell transplantation achieves better glucose control, a major obstacle is the shortage of donor organs. Recently, research has focused on stem cells which can be classified into embryonic stem cells (ESCs) and tissue stem cells (TSCs) to generate functional β cells. TSCs include the bone-marrow-, liver-, and pancreas-derived stem cells. In this review, we focus on treatment using bone marrow stem cells for type 1 and 2 DM. PMID:23671865

  18. Notch signaling regulates gastric antral LGR5 stem cell function

    PubMed Central

    Demitrack, Elise S; Gifford, Gail B; Keeley, Theresa M; Carulli, Alexis J; VanDussen, Kelli L; Thomas, Dafydd; Giordano, Thomas J; Liu, Zhenyi; Kopan, Raphael; Samuelson, Linda C

    2015-01-01

    The major signaling pathways regulating gastric stem cells are unknown. Here we report that Notch signaling is essential for homeostasis of LGR5+ antral stem cells. Pathway inhibition reduced proliferation of gastric stem and progenitor cells, while activation increased proliferation. Notch dysregulation also altered differentiation, with inhibition inducing mucous and endocrine cell differentiation while activation reduced differentiation. Analysis of gastric organoids demonstrated that Notch signaling was intrinsic to the epithelium and regulated growth. Furthermore, in vivo Notch manipulation affected the efficiency of organoid initiation from glands and single Lgr5-GFP stem cells, suggesting regulation of stem cell function. Strikingly, constitutive Notch activation in LGR5+ stem cells induced tissue expansion via antral gland fission. Lineage tracing using a multi-colored reporter demonstrated that Notch-activated stem cells rapidly generate monoclonal glands, suggesting a competitive advantage over unmanipulated stem cells. Notch activation was associated with increased mTOR signaling, and mTORC1 inhibition normalized NICD-induced increases in proliferation and gland fission. Chronic Notch activation induced undifferentiated, hyper-proliferative polyps, suggesting that aberrant activation of Notch in gastric stem cells may contribute to gastric tumorigenesis. PMID:26271103

  19. Derivation of the human embryonic stem cell line RCM1.

    PubMed

    De Sousa, P A; Tye, B J; Sneddon, S; Bruce, K; Dand, P; Russell, G; Collins, D M; Greenshields, A; McDonald, K; Bradburn, H; Gardner, J; Downie, J M; Courtney, A; Brison, D R

    2016-03-01

    The human embryonic stem cell line RCM-1 was derived from a failed to fertilise egg undergoing parthenogenetic stimulation. The cell line shows normal pluripotency marker expression and differentiation to three germ layers in vitro and in vivo. It has a normal 46XX female karyotype and microsatellite PCR identity, HLA and blood group typing data is available. PMID:27346018

  20. Characterizing the radioresponse of pluripotent and multipotent human stem cells.

    PubMed

    Lan, Mary L; Acharya, Munjal M; Tran, Katherine K; Bahari-Kashani, Jessica; Patel, Neal H; Strnadel, Jan; Giedzinski, Erich; Limoli, Charles L

    2012-01-01

    The potential capability of stem cells to restore functionality to diseased or aged tissues has prompted a surge of research, but much work remains to elucidate the response of these cells to genotoxic agents. To more fully understand the impact of irradiation on different stem cell types, the present study has analyzed the radioresponse of human pluripotent and multipotent stem cells. Human embryonic stem (ES) cells, human induced pluripotent (iPS) cells, and iPS-derived human neural stem cells (iPS-hNSCs) cells were irradiated and analyzed for cell survival parameters, differentiation, DNA damage and repair and oxidative stress at various times after exposure. While irradiation led to dose-dependent reductions in survival, the fraction of surviving cells exhibited dose-dependent increases in metabolic activity. Irradiation did not preclude germ layer commitment of ES cells, but did promote neuronal differentiation. ES cells subjected to irradiation exhibited early apoptosis and inhibition of cell cycle progression, but otherwise showed normal repair of DNA double-strand breaks. Cells surviving irradiation also showed acute and persistent increases in reactive oxygen and nitrogen species that were significant at nearly all post-irradiation times analyzed. We suggest that stem cells alter their redox homeostasis to adapt to adverse conditions and that radiation-induced oxidative stress plays a role in regulating the function and fate of stem cells within tissues compromised by radiation injury.

  1. Cancer stem cells and cell size: A causal link?

    PubMed

    Li, Qiuhui; Rycaj, Kiera; Chen, Xin; Tang, Dean G

    2015-12-01

    The majority of normal animal cells are 10-20 μm in diameter. Many signaling mechanisms, notably PI3K/Akt/mTOR, Myc, and Hippo pathways, tightly control and coordinate cell growth, cell size, cell division, and cell number during homeostasis. These regulatory mechanisms are frequently deregulated during tumorigenesis resulting in wide variations in cell sizes and increased proliferation in cancer cells. Here, we first review the evidence that primitive stem cells in adult tissues are quiescent and generally smaller than their differentiated progeny, suggesting a correlation between small cell sizes with the stemness. Conversely, increased cell size positively correlates with differentiation phenotypes. We then discuss cancer stem cells (CSCs) and present some evidence that correlates cell sizes with CSC activity. Overall, a causal link between CSCs and cell size is relatively weak and remains to be rigorously assessed. In the future, optimizing methods for isolating cells based on size should help elucidate the connection between cancer cell size and CSC characteristics.

  2. Derivation of three new human embryonic stem cell lines.

    PubMed

    Bradley, Cara K; Chami, Omar; Peura, Teija T; Bosman, Alexis; Dumevska, Biljana; Schmidt, Uli; Stojanov, Tomas

    2010-04-01

    Human embryonic stem cells are pluripotent cells capable of extensive self-renewal and differentiation to all cells of the embryo proper. Here, we describe the derivation and characterization of three Sydney IVF human embryonic stem cell lines not already reported elsewhere, designated SIVF001, SIVF002, and SIVF014. The cell lines display typical compact colony morphology of embryonic stem cells, have stable growth rates over more than 40 passages and are cytogenetically normal. Furthermore, the cell lines express pluripotency markers including Nanog, Oct4, SSEA3 and Tra-1-81, and are capable of generating teratoma cells derived from each of the three germ layers in immunodeficient mice. These experiments show that the cell lines constitute pluripotent stem cell lines. PMID:20198447

  3. Stem cells sources for intervertebral disc regeneration.

    PubMed

    Vadalà, Gianluca; Russo, Fabrizio; Ambrosio, Luca; Loppini, Mattia; Denaro, Vincenzo

    2016-05-26

    Intervertebral disc regeneration field is rapidly growing since disc disorders represent a major health problem in industrialized countries with very few possible treatments. Indeed, current available therapies are symptomatic, and surgical procedures consist in disc removal and spinal fusion, which is not immune to regardable concerns about possible comorbidities, cost-effectiveness, secondary risks and long-lasting outcomes. This review paper aims to share recent advances in stem cell therapy for the treatment of intervertebral disc degeneration. In literature the potential use of different adult stem cells for intervertebral disc regeneration has already been reported. Bone marrow mesenchymal stromal/stem cells, adipose tissue derived stem cells, synovial stem cells, muscle-derived stem cells, olfactory neural stem cells, induced pluripotent stem cells, hematopoietic stem cells, disc stem cells, and embryonic stem cells have been studied for this purpose either in vitro or in vivo. Moreover, several engineered carriers (e.g., hydrogels), characterized by full biocompatibility and prompt biodegradation, have been designed and combined with different stem cell types in order to optimize the local and controlled delivery of cellular substrates in situ. The paper overviews the literature discussing the current status of our knowledge of the different stem cells types used as a cell-based therapy for disc regeneration.

  4. Stem cells sources for intervertebral disc regeneration

    PubMed Central

    Vadalà, Gianluca; Russo, Fabrizio; Ambrosio, Luca; Loppini, Mattia; Denaro, Vincenzo

    2016-01-01

    Intervertebral disc regeneration field is rapidly growing since disc disorders represent a major health problem in industrialized countries with very few possible treatments. Indeed, current available therapies are symptomatic, and surgical procedures consist in disc removal and spinal fusion, which is not immune to regardable concerns about possible comorbidities, cost-effectiveness, secondary risks and long-lasting outcomes. This review paper aims to share recent advances in stem cell therapy for the treatment of intervertebral disc degeneration. In literature the potential use of different adult stem cells for intervertebral disc regeneration has already been reported. Bone marrow mesenchymal stromal/stem cells, adipose tissue derived stem cells, synovial stem cells, muscle-derived stem cells, olfactory neural stem cells, induced pluripotent stem cells, hematopoietic stem cells, disc stem cells, and embryonic stem cells have been studied for this purpose either in vitro or in vivo. Moreover, several engineered carriers (e.g., hydrogels), characterized by full biocompatibility and prompt biodegradation, have been designed and combined with different stem cell types in order to optimize the local and controlled delivery of cellular substrates in situ. The paper overviews the literature discussing the current status of our knowledge of the different stem cells types used as a cell-based therapy for disc regeneration. PMID:27247704

  5. Stem cells sources for intervertebral disc regeneration.

    PubMed

    Vadalà, Gianluca; Russo, Fabrizio; Ambrosio, Luca; Loppini, Mattia; Denaro, Vincenzo

    2016-05-26

    Intervertebral disc regeneration field is rapidly growing since disc disorders represent a major health problem in industrialized countries with very few possible treatments. Indeed, current available therapies are symptomatic, and surgical procedures consist in disc removal and spinal fusion, which is not immune to regardable concerns about possible comorbidities, cost-effectiveness, secondary risks and long-lasting outcomes. This review paper aims to share recent advances in stem cell therapy for the treatment of intervertebral disc degeneration. In literature the potential use of different adult stem cells for intervertebral disc regeneration has already been reported. Bone marrow mesenchymal stromal/stem cells, adipose tissue derived stem cells, synovial stem cells, muscle-derived stem cells, olfactory neural stem cells, induced pluripotent stem cells, hematopoietic stem cells, disc stem cells, and embryonic stem cells have been studied for this purpose either in vitro or in vivo. Moreover, several engineered carriers (e.g., hydrogels), characterized by full biocompatibility and prompt biodegradation, have been designed and combined with different stem cell types in order to optimize the local and controlled delivery of cellular substrates in situ. The paper overviews the literature discussing the current status of our knowledge of the different stem cells types used as a cell-based therapy for disc regeneration. PMID:27247704

  6. Stem cell transplantation for neuroblastoma.

    PubMed

    Fish, J D; Grupp, S A

    2008-01-01

    High-risk neuroblastoma is a childhood malignancy with a poor prognosis. Gradual improvements in survival have correlated with therapeutic intensity, and the ability to harvest, process and store autologous hematopoietic stem cells has allowed for dose intensification beyond marrow tolerance. The use of high-dose chemotherapy with autologous hematopoietic stem cell rescue in consolidation has resulted in improvements in survival, although further advances are still needed. Newer approaches to SCT and supportive care, most notably the transition to PBSC, have resulted in further improvement in survival and decreases in treatment-related mortality. Research into experimental approaches to hematopoietic SCT is ongoing.

  7. Neoplastic human embryonic stem cells as a model of radiation resistance of human cancer stem cells

    PubMed Central

    Dingwall, Steve; Lee, Jung Bok; Guezguez, Borhane; Fiebig, Aline; McNicol, Jamie; Boreham, Douglas; Collins, Tony J.; Bhatia, Mick

    2015-01-01

    Studies have implicated that a small sub-population of cells within a tumour, termed cancer stem cells (CSCs), have an enhanced capacity for tumour formation in multiple cancers and may be responsible for recurrence of the disease after treatment, including radiation. Although comparisons have been made between CSCs and bulk-tumour, the more important comparison with respect to therapy is between tumour-sustaining CSC versus normal stem cells that maintain the healthy tissue. However, the absence of normal known counterparts for many CSCs has made it difficult to compare the radiation responses of CSCs with the normal stem cells required for post-radiotherapy tissue regeneration and the maintenance of tissue homeostasis. Here we demonstrate that transformed human embryonic stem cells (t-hESCs), showing features of neoplastic progression produce tumours resistant to radiation relative to their normal counterpart upon injection into immune compromised mice. We reveal that t-hESCs have a reduced capacity for radiation induced cell death via apoptosis and exhibit altered cell cycle arrest relative to hESCs in vitro. t-hESCs have an increased expression of BclXL in comparison to their normal counterparts and re-sensitization of t-hESCs to radiation upon addition of BH3-only mimetic ABT737, suggesting that overexpression of BclXL underpins t-hESC radiation insensitivity. Using this novel discovery platform to investigate radiation resistance in human CSCs, our study indicates that chemotherapy targeting Bcl2-family members may prove to be an adjuvant to radiotherapy capable of targeting CSCs. PMID:26082437

  8. Neoplastic human embryonic stem cells as a model of radiation resistance of human cancer stem cells.

    PubMed

    Dingwall, Steve; Lee, Jung Bok; Guezguez, Borhane; Fiebig, Aline; McNicol, Jamie; Boreham, Douglas; Collins, Tony J; Bhatia, Mick

    2015-09-01

    Studies have implicated that a small sub-population of cells within a tumour, termed cancer stem cells (CSCs), have an enhanced capacity for tumour formation in multiple cancers and may be responsible for recurrence of the disease after treatment, including radiation. Although comparisons have been made between CSCs and bulk-tumour, the more important comparison with respect to therapy is between tumour-sustaining CSC versus normal stem cells that maintain the healthy tissue. However, the absence of normal known counterparts for many CSCs has made it difficult to compare the radiation responses of CSCs with the normal stem cells required for post-radiotherapy tissue regeneration and the maintenance of tissue homeostasis. Here we demonstrate that transformed human embryonic stem cells (t-hESCs), showing features of neoplastic progression produce tumours resistant to radiation relative to their normal counterpart upon injection into immune compromised mice. We reveal that t-hESCs have a reduced capacity for radiation induced cell death via apoptosis and exhibit altered cell cycle arrest relative to hESCs in vitro. t-hESCs have an increased expression of BclXL in comparison to their normal counterparts and re-sensitization of t-hESCs to radiation upon addition of BH3-only mimetic ABT737, suggesting that overexpression of BclXL underpins t-hESC radiation insensitivity. Using this novel discovery platform to investigate radiation resistance in human CSCs, our study indicates that chemotherapy targeting Bcl2-family members may prove to be an adjuvant to radiotherapy capable of targeting CSCs.

  9. Stem cells and lung cancer: future therapeutic targets?

    PubMed

    Alison, Malcolm R; Lebrenne, Arielle C; Islam, Shahriar

    2009-09-01

    In both the UK and USA more people die of lung cancer than any other type of cancer. Lung cancer's high mortality rate is also reflected on a global scale, with lung cancer accounting for more than 1 million deaths per year. In tissues with ordered structure such a lung epithelia, it is likely that the cancers have their origins in normal adult stem cells, and then the tumours themselves are maintained by a population of malignant stem cells - so-called cancer stem cells. This review examines both these postulates in animal models and in the clinical setting, noting that stem cell niches appear to foster tumour development, and that drug resistance can often be attributed to malignant cells with stem cell properties. PMID:19653862

  10. The regulatory niche of intestinal stem cells.

    PubMed

    Sailaja, Badi Sri; He, Xi C; Li, Linheng

    2016-09-01

    The niche constitutes a unique category of cells that support the microenvironment for the maintenance and self-renewal of stem cells. Intestinal stem cells reside at the base of the crypt, which contains adjacent epithelial cells, stromal cells and smooth muscle cells, and soluble and cell-associated growth and differentiation factors. We summarize here recent advances in our understanding of the crucial role of the niche in regulating stem cells. The stem cell niche maintains a balance among quiescence, proliferation and regeneration of intestinal stem cells after injury. Mesenchymal cells, Paneth cells, immune cells, endothelial cells and neural cells are important regulatory components that secrete niche ligands, growth factors and cytokines. Intestinal homeostasis is regulated by niche signalling pathways, specifically Wnt, bone morphogenetic protein, Notch and epidermal growth factor. These insights into the regulatory stem cell niche during homeostasis and post-injury regeneration offer the potential to accelerate development of therapies for intestine-related disorders.

  11. The regulatory niche of intestinal stem cells.

    PubMed

    Sailaja, Badi Sri; He, Xi C; Li, Linheng

    2016-09-01

    The niche constitutes a unique category of cells that support the microenvironment for the maintenance and self-renewal of stem cells. Intestinal stem cells reside at the base of the crypt, which contains adjacent epithelial cells, stromal cells and smooth muscle cells, and soluble and cell-associated growth and differentiation factors. We summarize here recent advances in our understanding of the crucial role of the niche in regulating stem cells. The stem cell niche maintains a balance among quiescence, proliferation and regeneration of intestinal stem cells after injury. Mesenchymal cells, Paneth cells, immune cells, endothelial cells and neural cells are important regulatory components that secrete niche ligands, growth factors and cytokines. Intestinal homeostasis is regulated by niche signalling pathways, specifically Wnt, bone morphogenetic protein, Notch and epidermal growth factor. These insights into the regulatory stem cell niche during homeostasis and post-injury regeneration offer the potential to accelerate development of therapies for intestine-related disorders. PMID:27060879

  12. Programming embryonic stem cells to neuronal subtypes

    PubMed Central

    Peljto, Mirza; Wichterle, Hynek

    2010-01-01

    Richness of neural circuits and specificity of neuronal connectivity depends on the diversification of nerve cells into functionally and molecularly distinct subtypes. While efficient methods for directed differentiation of embryonic stem cells (ESCs) into multiple principal neuronal classes have been established, only a few studies systematically examined the subtype diversity of in vitro derived nerve cells. Here we review evidence based on molecular and in vivo transplantation studies that ESC-derived spinal motor neurons and cortical layer V pyramidal neurons acquire subtype specific functional properties. We discuss similarities and differences in the role of cell intrinsic transcriptional programs, extrinsic signals and cell-cell interactions during subtype diversification of the two classes of nerve cells. We conclude that the high degree of fidelity with which differentiating ESCs recapitulate normal embryonic development provides a unique opportunity to explore developmental processes underlying specification of mammalian neuronal diversity in a simplified and experimentally accessible system. PMID:20970319

  13. Modeling the clonal heterogeneity of stem cells

    PubMed Central

    2010-01-01

    Recent experimental studies suggest that tissue stem cell pools are composed of functionally diverse clones. Metapopulation models in ecology concentrate on collections of populations and their role in stabilizing coexistence and maintaining selected genetic or epigenetic variation. Such models are characterized by expansion and extinction of spatially distributed populations. We develop a mathematical framework derived from the multispecies metapopulation model of Tilman et al (1994) to study the dynamics of heterogeneous stem cell metapopulations. In addition to normal stem cells, the model can be applied to cancer cell populations and their response to treatment. In our model disturbances may lead to expansion or contraction of cells with distinct properties, reflecting proliferation, apoptosis, and clonal competition. We first present closed-form expressions for the basic model which defines clonal dynamics in the presence of exogenous global disturbances. We then extend the model to include disturbances which are periodic and which may affect clones differently. Within the model framework, we propose a method to devise an optimal strategy of treatments to regulate expansion, contraction, or mutual maintenance of cells with specific properties. PMID:21083923

  14. Functional repair with neural stem cells.

    PubMed

    Sinden, J D; Stroemer, P; Grigoryan, G; Patel, S; French, S J; Hodges, H

    2000-01-01

    Approval to commence phase I/II clinical trials with neural stem cells requires proof of concept in well-accepted animal models of human neurological disease or injury. We initially showed that the conditionally immortal MHP36 line of hippocampal origin (derived from the H-2Kb-tsA58 transgenic mouse) was effective in repopulating CA1 neurons in models of global ischaemia and repairing cognitive function, and have now shown that this line is multifunctional. MHP36 cells are effective in restoring spatial memory deficits in rats after excitotoxic lesions of the cholinergic projections to cortex and hippocampus and in rats showing cognitive impairments due to normal ageing. Moreover, grafts of MHP36 cells are effective in reversing sensory and motor deficits and reducing lesion volume as a consequence of occlusion of the middle cerebral artery, the major cause of stroke. In contrast, MHP36 cell grafts were unable to repair motor asymmetries in rats with unilateral 6-hydroxydopamine lesions of the nigrostriatal dopamine system, the prototype rodent model of Parkinson's disease. These data show that conditionally immortal neuroepithelial stem cells are multifunctional, being able to repair diverse types of brain damage. However, there are limitations to this multifunctionality, suggesting that lines from different regions of the developing brain will be required to treat different brain diseases. ReNeuron is currently developing human neuroepithelial stem cell lines from different brain regions and with similar reparative properties to our murine lines. PMID:11131543

  15. Becoming a Blood Stem Cell Donor

    MedlinePlus

    ... total__ Find out why Close Becoming a Blood Stem Cell Donor NCIcancertopics Subscribe Subscribed Unsubscribe 359 359 Loading... ... Ever considered becoming a bone marrow or blood stem cell donor? Follow this true story of a former ...

  16. Stem Cell Transplant Patients and Fungal Infections

    MedlinePlus

    ... Foodborne, Waterborne, and Environmental Diseases Mycotic Diseases Branch Stem Cell Transplant Patients and Fungal Infections Recommend on Facebook ... Mold . Top of Page Preventing fungal infections in stem cell transplant patients Fungi are difficult to avoid because ...

  17. Adult Stem Cells and Diabetes Therapy

    PubMed Central

    Ilgun, Handenur; Kim, Joseph William; Luo, LuGuang

    2016-01-01

    The World Health Organization estimates that diabetes will be the fourth most prevalent disease by 2050. Developing a new therapy for diabetes is a challenge for researchers and clinicians in field. Many medications are being used for treatment of diabetes however with no conclusive and effective results therefore alternative therapies are required. Stem cell therapy is a promising tool for diabetes therapy, and it has involved embryonic stem cells, adult stem cells, and pluripotent stem cells. In this review, we focus on adult stem cells, especial human bone marrow stem cells (BM) for diabetes therapy, its history, and current development. We discuss prospects for future diabetes therapy such as induced pluripotent stem cells which have popularity in stem cell research area. PMID:27123495

  18. Stem cell technology for neurodegenerative diseases.

    PubMed

    Lunn, J Simon; Sakowski, Stacey A; Hur, Junguk; Feldman, Eva L

    2011-09-01

    Over the past 20 years, stem cell technologies have become an increasingly attractive option to investigate and treat neurodegenerative diseases. In the current review, we discuss the process of extending basic stem cell research into translational therapies for patients suffering from neurodegenerative diseases. We begin with a discussion of the burden of these diseases on society, emphasizing the need for increased attention toward advancing stem cell therapies. We then explain the various types of stem cells utilized in neurodegenerative disease research, and outline important issues to consider in the transition of stem cell therapy from bench to bedside. Finally, we detail the current progress regarding the applications of stem cell therapies to specific neurodegenerative diseases, focusing on Parkinson disease, Huntington disease, Alzheimer disease, amyotrophic lateral sclerosis, and spinal muscular atrophy. With a greater understanding of the capacity of stem cell technologies, there is growing public hope that stem cell therapies will continue to progress into realistic and efficacious treatments for neurodegenerative diseases.

  19. Perspectives on human stem cell research.

    PubMed

    Jung, Kyu Won

    2009-09-01

    Human stem cell research draws not only scientists' but the public's attention. Human stem cell research is considered to be able to identify the mechanism of human development and change the paradigm of medical practices. However, there are heated ethical and legal debates about human stem cell research. The core issue is that of human dignity and human life. Some prefer human adult stem cell research or iPS cell research, others hES cell research. We do not need to exclude any type of stem cell research because each has its own merits and issues, and they can facilitate the scientific revolution when working together.

  20. New Findings on Breast Cancer Stem Cells: A Review.

    PubMed

    Bozorgi, Azam; Khazaei, Mozafar; Khazaei, Mohammad Rasool

    2015-12-01

    Since the introduction of the "cancer stem cell" theory, significant developments have been made in the understanding of cancer and the heterogenic structure of tumors. In 2003, with the isolation of cancer stem cells from the first solid tumor, breast cancer, and recognition of the tumorigenicity of these cells, this theory suggested that the main reason for therapy failure might be the presence of cancer stem cells. This review article describes breast cancer stem cell origin, the related cellular and molecular characteristics, signaling pathways, and therapy resistance mechanisms. The databases PubMed, SCOPUS, and Embase were explored, and articles published on these topics between 1992 and 2015 were investigated. It appears that this small subpopulation of cells, with the capacity for self-renewal and a high proliferation rate, originate from normal stem cells, are identified by specific markers such as CD44(+)/CD24(-/low), and enhance a tumor's capacity for metastasis, invasion, and therapy resistance. Cancer stem cell characteristics depend on their interactions with their microenvironment as well as on the inducing factors and elements. Although uncertainties about breast cancer stem cells exist, many of researchers believe that cancer stem cells should be considered as possible therapeutic targets.

  1. New Findings on Breast Cancer Stem Cells: A Review

    PubMed Central

    Bozorgi, Azam; Khazaei, Mohammad Rasool

    2015-01-01

    Since the introduction of the "cancer stem cell" theory, significant developments have been made in the understanding of cancer and the heterogenic structure of tumors. In 2003, with the isolation of cancer stem cells from the first solid tumor, breast cancer, and recognition of the tumorigenicity of these cells, this theory suggested that the main reason for therapy failure might be the presence of cancer stem cells. This review article describes breast cancer stem cell origin, the related cellular and molecular characteristics, signaling pathways, and therapy resistance mechanisms. The databases PubMed, SCOPUS, and Embase were explored, and articles published on these topics between 1992 and 2015 were investigated. It appears that this small subpopulation of cells, with the capacity for self-renewal and a high proliferation rate, originate from normal stem cells, are identified by specific markers such as CD44+/CD24-/low, and enhance a tumor's capacity for metastasis, invasion, and therapy resistance. Cancer stem cell characteristics depend on their interactions with their microenvironment as well as on the inducing factors and elements. Although uncertainties about breast cancer stem cells exist, many of researchers believe that cancer stem cells should be considered as possible therapeutic targets. PMID:26770236

  2. Cell cycle measurement of mouse hematopoietic stem/progenitor cells.

    PubMed

    Chitteti, Brahmananda Reddy; Srour, Edward F

    2014-01-01

    Lifelong production of blood cells is sustained by hematopoietic stem cells (HSC). HSC reside in a mitotically quiescent state within specialized areas of the bone marrow (BM) microenvironment known as the hematopoietic niche (HN). HSC enter into active phases of cell cycle in response to intrinsic and extrinsic biological cues thereby undergoing differentiation or self-renewal divisions. Quiescent and mitotically active HSC have different metabolic states and different functional abilities such as engraftment and BM repopulating potential following their transplantation into conditioned recipients. Recent studies reveal that various cancers also utilize the same mechanisms of quiescence as normal stem cells and preserve the root of malignancy thus contributing to relapse and metastasis. Therefore, exploring the stem cell behavior and function in conjunction with their cell cycle status has significant clinical implications in HSC transplantation and in treating cancers. In this chapter, we describe methodologies to isolate or analytically measure the frequencies of quiescent (G0) and active (G1, S, and G2-M) hematopoietic progenitor and stem cells among murine BM cells.

  3. Epigenetic Regulation of Hematopoietic Stem Cells.

    PubMed

    Sharma, Shilpa; Gurudutta, Gangenahalli

    2016-05-30

    Hematopoietic stem cells are endowed with a distinct potential to bolster self-renewal and to generate progeny that differentiate into mature cells of myeloid and lymphoid lineages. Both hematopoietic stem cells and mature cells have the same genome, but their gene expression is controlled by an additional layer of epigenetics such as DNA methylation and post-translational histone modifications, enabling each cell-type to acquire various forms and functions. Until recently, several studies have largely focussed on the transcription factors andniche factors for the understanding of the molecular mechanisms by which hematopoietic cells replicate and differentiate. Several lines of emerging evidence suggest that epigenetic modifications eventually result in a defined chromatin structure and an "individual" gene expression pattern, which play an essential role in the regulation of hematopoietic stem cell self-renewal and differentiation. Distinct epigenetic marks decide which sets of genes may be expressed and which genes are kept silent. Epigenetic mechanisms are interdependent and ensure lifelong production of blood and bone marrow, thereby contributing to stem cell homeostasis. The epigenetic analysis of hematopoiesis raises the exciting possibility that chromatin structure is dynamic enough for regulated expression of genes. Though controlled chromatin accessibility plays an essential role in maintaining blood homeostasis; mutations in chromatin impacts on the regulation of genes critical to the development of leukemia. In this review, we explored the contribution of epigenetic machinery which has implications for the ramification of molecular details of hematopoietic self-renewal for normal development and underlying events that potentially co-operate to induce leukemia.

  4. [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.

  5. Stem Cell Research Policies around the World

    PubMed Central

    Dhar, Deepali; Hsi-en Ho, John

    2009-01-01

    The proliferation of stem cell research, conflated with its ethical and moral implications, has led governments to attempt regulation of both the science and funding of stem cells. Due to a diversity of opinions and cultural viewpoints, no single policy or set of rules exist to govern stem cell research. Instead, each country has developed its own policy. The following map catalogs the general legal and political milleu regarding stem cell research by country. PMID:19774124

  6. Actions of endocrine-disrupting chemicals on stem/progenitor cells during development and disease.

    PubMed

    Kopras, Elizabeth; Potluri, Veena; Bermudez, Mei-Ling; Williams, Karin; Belcher, Scott; Kasper, Susan

    2014-04-01

    Development and fate of the stem cell are regulated by extrinsic signals from the environment. Endocrine-disrupting chemicals which perturb hormonal signaling in utero and during early childhood may cause deregulation of multiple developmental processes, ranging from breakdown of stem cell niche architecture, developmental reprograming and altered stem cell fate to impaired organ and gonad development and sexual differentiation. Therefore, study of the environmental effects on stem cell integrity and normal development is a new and emerging focus for developmental biologists and cell toxicologists. When combined with new human and mouse stem cell-based models, stem cell differentiation dynamics can be studied in more biologically relevant ways. In this study, we review the current status of our understanding of the molecular mechanisms by which endocrine disruptors alter embryonic stem cell and adult stem/progenitor cell fate, organ development, cancer stem cell activity, and tumorigenesis.

  7. Stem cells and colorectal carcinogenesis

    PubMed Central

    Stoian, M; Stoica, V; Radulian, G

    2016-01-01

    Abstract Colorectal cancer represents an important cause of mortality and morbidity. Unfortunately, the physiopathology is still under study. There are theories about carcinogenesis and it is known that not only a single factor is responsible for the development of a tumor, but several conditions. Stem cells are a promising target for the treatment of colorectal cancer, along with the environment that has an important role. It has been postulated that mutations within the adult colonic stem cells may induce neoplastic changes. This theory is based on the observation that within a colon cancer, less than 1% of the neoplastic cells have the ability to regenerate the tumor and therefore they are responsible for recurrence. It is important to know that a new way of treatment needs to be found, since these cells are resistant to chemotherapy and radiotherapy.

  8. Stem/Progenitor cells in vascular regeneration.

    PubMed

    Zhang, Li; Xu, Qingbo

    2014-06-01

    A series of studies has been presented in the search for proof of circulating and resident vascular progenitor cells, which can differentiate into endothelial and smooth muscle cells and pericytes in animal and human studies. In terms of pluripotent stem cells, including embryonic stem cells, iPS, and partial-iPS cells, they display a great potential for vascular lineage differentiation. Development of stem cell therapy for treatment of vascular and ischemic diseases remains a major challenging research field. At the present, there is a clear expansion of research into mechanisms of stem cell differentiation into vascular lineages that are tested in animal models. Although there are several clinical trials ongoing that primarily focus on determining the benefits of stem cell transplantation in ischemic heart or peripheral ischemic tissues, intensive investigation for translational aspects of stem cell therapy would be needed. It is a hope that stem cell therapy for vascular diseases could be developed for clinic application in the future.

  9. College Students' Conceptions of Stem Cells, Stem Cell Research, and Cloning

    ERIC Educational Resources Information Center

    Concannon, James P.; Siegel, Marcelle A.; Halverson, Kristy; Freyermuth, Sharyn

    2010-01-01

    In this study, we examined 96 undergraduate non-science majors' conceptions of stem cells, stem cell research, and cloning. This study was performed at a large, Midwest, research extensive university. Participants in the study were asked to answer 23 questions relating to stem cells, stem cell research, and cloning in an on-line assessment before…

  10. Embryonic stem cells: prospects for developmental biology and cell therapy.

    PubMed

    Wobus, Anna M; Boheler, Kenneth R

    2005-04-01

    Stem cells represent natural units of embryonic development and tissue regeneration. Embryonic stem (ES) cells, in particular, possess a nearly unlimited self-renewal capacity and developmental potential to differentiate into virtually any cell type of an organism. Mouse ES cells, which are established as permanent cell lines from early embryos, can be regarded as a versatile biological system that has led to major advances in cell and developmental biology. Human ES cell lines, which have recently been derived, may additionally serve as an unlimited source of cells for regenerative medicine. Before therapeutic applications can be realized, important problems must be resolved. Ethical issues surround the derivation of human ES cells from in vitro fertilized blastocysts. Current techniques for directed differentiation into somatic cell populations remain inefficient and yield heterogeneous cell populations. Transplanted ES cell progeny may not function normally in organs, might retain tumorigenic potential, and could be rejected immunologically. The number of human ES cell lines available for research may also be insufficient to adequately determine their therapeutic potential. Recent molecular and cellular advances with mouse ES cells, however, portend the successful use of these cells in therapeutics. This review therefore focuses both on mouse and human ES cells with respect to in vitro propagation and differentiation as well as their use in basic cell and developmental biology and toxicology and presents prospects for human ES cells in tissue regeneration and transplantation.

  11. Identify multiple myeloma stem cells: Utopia?

    PubMed Central

    Saltarella, Ilaria; Lamanuzzi, Aurelia; Reale, Antonia; Vacca, Angelo; Ria, Roberto

    2015-01-01

    Multiple myeloma (MM) is a hematologic malignancy of monoclonal plasma cells which remains incurable despite recent advances in therapies. The presence of cancer stem cells (CSCs) has been demonstrated in many solid and hematologic tumors, so the idea of CSCs has been proposed for MM, even if MM CSCs have not been define yet. The existence of myeloma CSCs with clonotypic B and clonotypic non B cells was postulated by many groups. This review aims to focus on these distinct clonotypic subpopulations and on their ability to develop and sustain MM. The bone marrow microenvironment provides to MM CSCs self-renewal, survival and drug resistance thanks to the presence of normal and cancer stem cell niches. The niches and CSCs interact each other through adhesion molecules and the interplay between ligands and receptors activates stemness signaling (Hedgehog, Wnt and Notch pathways). MM CSCs are also supposed to be responsible for drug resistance that happens in three steps from the initial cancer cell homing microenvironment-mediated to development of microenvironment-independent drug resistance. In this review, we will underline all these aspects of MM CSCs. PMID:25621108

  12. Identify multiple myeloma stem cells: Utopia?

    PubMed

    Saltarella, Ilaria; Lamanuzzi, Aurelia; Reale, Antonia; Vacca, Angelo; Ria, Roberto

    2015-01-26

    Multiple myeloma (MM) is a hematologic malignancy of monoclonal plasma cells which remains incurable despite recent advances in therapies. The presence of cancer stem cells (CSCs) has been demonstrated in many solid and hematologic tumors, so the idea of CSCs has been proposed for MM, even if MM CSCs have not been define yet. The existence of myeloma CSCs with clonotypic B and clonotypic non B cells was postulated by many groups. This review aims to focus on these distinct clonotypic subpopulations and on their ability to develop and sustain MM. The bone marrow microenvironment provides to MM CSCs self-renewal, survival and drug resistance thanks to the presence of normal and cancer stem cell niches. The niches and CSCs interact each other through adhesion molecules and the interplay between ligands and receptors activates stemness signaling (Hedgehog, Wnt and Notch pathways). MM CSCs are also supposed to be responsible for drug resistance that happens in three steps from the initial cancer cell homing microenvironment-mediated to development of microenvironment-independent drug resistance. In this review, we will underline all these aspects of MM CSCs. PMID:25621108

  13. Identify multiple myeloma stem cells: Utopia?

    PubMed

    Saltarella, Ilaria; Lamanuzzi, Aurelia; Reale, Antonia; Vacca, Angelo; Ria, Roberto

    2015-01-26

    Multiple myeloma (MM) is a hematologic malignancy of monoclonal plasma cells which remains incurable despite recent advances in therapies. The presence of cancer stem cells (CSCs) has been demonstrated in many solid and hematologic tumors, so the idea of CSCs has been proposed for MM, even if MM CSCs have not been define yet. The existence of myeloma CSCs with clonotypic B and clonotypic non B cells was postulated by many groups. This review aims to focus on these distinct clonotypic subpopulations and on their ability to develop and sustain MM. The bone marrow microenvironment provides to MM CSCs self-renewal, survival and drug resistance thanks to the presence of normal and cancer stem cell niches. The niches and CSCs interact each other through adhesion molecules and the interplay between ligands and receptors activates stemness signaling (Hedgehog, Wnt and Notch pathways). MM CSCs are also supposed to be responsible for drug resistance that happens in three steps from the initial cancer cell homing microenvironment-mediated to development of microenvironment-independent drug resistance. In this review, we will underline all these aspects of MM CSCs.

  14. Setting FIRES to Stem Cell Research

    ERIC Educational Resources Information Center

    Miller, Roxanne Grietz

    2005-01-01

    The goal of this lesson is to present the basic scientific knowledge about stem cells, the promise of stem cell research to medicine, and the ethical considerations and arguments involved. One of the challenges of discussing stem cell research is that the field is constantly evolving and the most current information changes almost daily. Few…

  15. Blood-Forming Stem Cell Transplants

    MedlinePlus

    ... Health Professionals Questions to Ask about Your Treatment Research Blood-Forming Stem Cell Transplants On This Page What are bone marrow ... are evaluating BMT and PBSCT in clinical trials (research studies) for the treatment ... are the donor’s stem cells matched to the patient’s stem cells in allogeneic ...

  16. Molecule mechanism of stem cells in Arabidopsis thaliana.

    PubMed

    Zhang, Wenjin; Yu, Rongming

    2014-07-01

    Plants possess the ability to continually produce new tissues and organs throughout their life. Unlike animals, plants are exposed to extreme variations in environmental conditions over the course of their lives. The vitality of plants is so powerful that they can survive several hundreds of years or even more making it an amazing miracle that comes from plant stem cells. The stem cells continue to divide to renew themselves and provide cells for the formation of leaves, stems, and flowers. Stem cells are not only quiescent but also immortal, pluripotent and homeostatic. Stem cells are the magic cells that repair tissues and regenerate organs. During the past decade, scholars around the world have paid more and more attention toward plant stem cells. At present, the major challenge is in relating molecule action mechanism to root apical meristem, shoot apical meristem and vascular system. The coordination between stem cells maintenance and differentiation is critical for normal plant growth and development. Elements such as phytohormones, transcription factors and some other known or unknown genes cooperate to balance this process. In this review, Arabidopsis thaliana as a pioneer system, we highlight recent developments in molecule modulating, illustrating how plant stem cells generate new mechanistic insights into the regulation of plants growth and development.

  17. Methods for Stem Cell Production and Therapy

    NASA Technical Reports Server (NTRS)

    Claudio, Pier Paolo (Inventor); Valluri, Jagan V. (Inventor)

    2015-01-01

    The present invention relates to methods for rapidly expanding a stem cell population with or without culture supplements in simulated microgravity conditions. The present invention relates to methods for rapidly increasing the life span of stem cell populations without culture supplements in simulated microgravity conditions. The present invention also relates to methods for increasing the sensitivity of cancer stem cells to chemotherapeutic agents by culturing the cancer stem cells under microgravity conditions and in the presence of omega-3 fatty acids. The methods of the present invention can also be used to proliferate cancer cells by culturing them in the presence of omega-3 fatty acids. The present invention also relates to methods for testing the sensitivity of cancer cells and cancer stem cells to chemotherapeutic agents by culturing the cancer cells and cancer stem cells under microgravity conditions. The methods of the present invention can also be used to produce tissue for use in transplantation by culturing stem cells or cancer stem cells under microgravity conditions. The methods of the present invention can also be used to produce cellular factors and growth factors by culturing stem cells or cancer stem cells under microgravity conditions. The methods of the present invention can also be used to produce cellular factors and growth factors to promote differentiation of cancer stem cells under microgravity conditions.

  18. Modern stem cell therapy: approach to disease.

    PubMed

    Zemljic, Mateja; Pejkovic, Bozena; Krajnc, Ivan; Kocbek, Lidija

    2015-12-01

    Various types of stem cells exist, each with their own advantages and disadvantages. Considering the current available evidence, important preclinical and clinical studies regarding the therapeutic potential of stem cells, stem cell therapy might be the important strategy for tissue repair. The development of stem cell therapy for tissue repair has primarily relied on stem cells, especially mesenchymal stem cells. Multilineage differentiation into all of the described cells are considered as important candidates for a range of diseases like neurological diseases, cardiovascular diseases, gastrointestinal cancer and genetic defects, as well as for acute and chronic wounds healing and pharmaceutical treatment. We review the properties and multipotency of stem cells and their differentiation potential, once cultured under specific growth conditions, for use in cell-based therapies and functional tissue replacement.

  19. Nuclear Mechanics and Stem Cell Differentiation.

    PubMed

    Mao, Xinjian; Gavara, Nuria; Song, Guanbin

    2015-12-01

    Stem cells are characterized by their self-renewal and multi-lineage differentiation potential. Stem cell differentiation is a prerequisite for the application of stem cells in regenerative medicine and clinical therapy. In addition to chemical stimulation, mechanical cues play a significant role in regulating stem cell differentiation. The integrity of mechanical sensors is necessary for the ability of cells to respond to mechanical signals. The nucleus, the largest and stiffest cellular organelle, interacts with the cytoskeleton as a key mediator of cell mechanics. Nuclear mechanics are involved in the complicated interactions of lamins, chromatin and nucleoskeleton-related proteins. Thus, stem cell differentiation is intimately associated with nuclear mechanics due to its indispensable role in mechanotransduction and mechanical response. This paper reviews several main contributions of nuclear mechanics, highlights the hallmarks of the nuclear mechanics of stem cells, and provides insight into the relationship between nuclear mechanics and stem cell differentiation, which may guide clinical applications in the future.

  20. SILAC proteomics of planarians identifies Ncoa5 as a conserved component of pluripotent stem cells.

    PubMed

    Böser, Alexander; Drexler, Hannes C A; Reuter, Hanna; Schmitz, Henning; Wu, Guangming; Schöler, Hans R; Gentile, Luca; Bartscherer, Kerstin

    2013-11-27

    Planarian regeneration depends on the presence of pluripotent stem cells in the adult. We developed an in vivo stable isotope labeling by amino acids in cell culture (SILAC) protocol in planarians to identify proteins that are enriched in planarian stem cells. Through a comparison of SILAC proteomes of normal and stem cell-depleted planarians and of a stem cell-enriched population of sorted cells, we identified hundreds of stem cell proteins. One of these is an ortholog of nuclear receptor coactivator-5 (Ncoa5/CIA), which is known to regulate estrogen-receptor-mediated transcription in human cells. We show that Ncoa5 is essential for the maintenance of the pluripotent stem cell population in planarians and that a putative mouse ortholog is expressed in pluripotent cells of the embryo. Our study thus identifies a conserved component of pluripotent stem cells, demonstrating that planarians, in particular, when combined with in vivo SILAC, are a powerful model in stem cell research.

  1. Stem cells: science, policy, and ethics.

    PubMed

    Fischbach, Gerald D; Fischbach, Ruth L

    2004-11-01

    Human embryonic stem cells offer the promise of a new regenerative medicine in which damaged adult cells can be replaced with new cells. Research is needed to determine the most viable stem cell lines and reliable ways to promote the differentiation of pluripotent stem cells into specific cell types (neurons, muscle cells, etc). To create new cell lines, it is necessary to destroy preimplantation blastocysts. This has led to an intense debate that threatens to limit embryonic stem cell research. The profound ethical issues raised call for informed, dispassionate debate.

  2. Muscle stem cells at a glance

    PubMed Central

    Wang, Yu Xin; Dumont, Nicolas A.; Rudnicki, Michael A.

    2014-01-01

    ABSTRACT Muscle stem cells facilitate the long-term regenerative capacity of skeletal muscle. This self-renewing population of satellite cells has only recently been defined through genetic and transplantation experiments. Although muscle stem cells remain in a dormant quiescent state in uninjured muscle, they are poised to activate and produce committed progeny. Unlike committed myogenic progenitor cells, the self-renewal capacity gives muscle stem cells the ability to engraft as satellite cells and capitulate long-term regeneration. Similar to other adult stem cells, understanding the molecular regulation of muscle stem cells has significant implications towards the development of pharmacological or cell-based therapies for muscle disorders. This Cell Science at a Glance article and accompanying poster will review satellite cell characteristics and therapeutic potential, and provide an overview of the muscle stem cell hallmarks: quiescence, self-renewal and commitment. PMID:25300792

  3. Cell motion predicts human epidermal stemness

    PubMed Central

    Toki, Fujio; Tate, Sota; Imai, Matome; Matsushita, Natsuki; Shiraishi, Ken; Sayama, Koji; Toki, Hiroshi; Higashiyama, Shigeki

    2015-01-01

    Image-based identification of cultured stem cells and noninvasive evaluation of their proliferative capacity advance cell therapy and stem cell research. Here we demonstrate that human keratinocyte stem cells can be identified in situ by analyzing cell motion during their cultivation. Modeling experiments suggested that the clonal type of cultured human clonogenic keratinocytes can be efficiently determined by analysis of early cell movement. Image analysis experiments demonstrated that keratinocyte stem cells indeed display a unique rotational movement that can be identified as early as the two-cell stage colony. We also demonstrate that α6 integrin is required for both rotational and collective cell motion. Our experiments provide, for the first time, strong evidence that cell motion and epidermal stemness are linked. We conclude that early identification of human keratinocyte stem cells by image analysis of cell movement is a valid parameter for quality control of cultured keratinocytes for transplantation. PMID:25897083

  4. Pathological niche environment transforms dermal stem cells to keloid stem cells: a hypothesis of keloid formation and development.

    PubMed

    Qu, Miao; Song, Nang; Chai, Gang; Wu, Xiaoli; Liu, Wei

    2013-11-01

    Keloid is a disease that is difficult to cure because of its high recurrence rate after chemotherapy or radiotherapy, therefore it is considered as a benign skin tumor. Tumor stem cells are proposed as the source for tumor development and post-therapy recurrence. Interestingly, keloid stem cells have also been discovered, which share some characters with those of skin progenitor cells. Keloid patients possess specific diathesis including genetic predisposition and gene mutation, abnormal levels of hormones, growth factors and cytokines, and strong inflammatory response. This article reviews related literatures and hypothesizes that keloid stem cells might be transformed from normal dermal progenitor cells in the pathological niche of keloid tissues. These keloid stem cells are highly self-renewal and drug resistant, and can sustain themselves by asymmetric division, and continually generate new keloid cells to replenish the cells killed by drugs or radiation, thus leading to over growth of keloid and high post-therapy recurrence rate.

  5. Satellite Cells and the Muscle Stem Cell Niche

    PubMed Central

    Yin, Hang; Price, Feodor

    2013-01-01

    Adult skeletal muscle in mammals is a stable tissue under normal circumstances but has remarkable ability to repair after injury. Skeletal muscle regeneration is a highly orchestrated process involving the activation of various cellular and molecular responses. As skeletal muscle stem cells, satellite cells play an indispensible role in this process. The self-renewing proliferation of satellite cells not only maintains the stem cell population but also provides numerous myogenic cells, which proliferate, differentiate, fuse, and lead to new myofiber formation and reconstitution of a functional contractile apparatus. The complex behavior of satellite cells during skeletal muscle regeneration is tightly regulated through the dynamic interplay between intrinsic factors within satellite cells and extrinsic factors constituting the muscle stem cell niche/microenvironment. For the last half century, the advance of molecular biology, cell biology, and genetics has greatly improved our understanding of skeletal muscle biology. Here, we review some recent advances, with focuses on functions of satellite cells and their niche during the process of skeletal muscle regeneration. PMID:23303905

  6. Embryonic Stem Cell Patents and Human Dignity

    PubMed Central

    Resnik, David B.

    2009-01-01

    This article examines the assertion that human embryonic stem cells patents are immoral because they violate human dignity. After analyzing the concept of human dignity and its role in bioethics debates, this article argues that patents on human embryos or totipotent embryonic stem cells violate human dignity, but that patents on pluripotent or multipotent stem cells do not. Since patents on pluripotent or multipotent stem cells may still threaten human dignity by encouraging people to treat embryos as property, patent agencies should carefully monitor and control these patents to ensure that patents are not inadvertently awarded on embryos or totipotent stem cells. PMID:17922198

  7. Stem cell maintenance in a different niche

    PubMed Central

    Ahn, Ji Yeon; Lee, Seung Tae

    2013-01-01

    To overcome the difficulty of controlling stem cell fate and function in applications to regenerative medicine, a number of alternative approaches have been made. Recent reports demonstrate that a non-cellular niche modulating the biophysical microenvironment with chemical factors can support stem cell self-renewal. In our previous studies, early establishment was executed to optimize biophysical factors and it was subsequently found that the microgeometry of the extracellular matrix made huge differences in stem cell behavior and phenotype. We review here a three-dimensional, non-cellular niche designed to support stem cell self-renewal. The characteristics of stem cells under the designed system are further discussed. PMID:23875159

  8. Isoflurane suppresses the self-renewal of normal mouse neural stem cells in a p53-dependent manner by activating the Lkb1-p53-p21 signalling pathway.

    PubMed

    Hou, Lengchen; Liu, Te; Wang, Jian

    2015-11-01

    Isoflurane is widely used in anaesthesia for surgical operations. However, whether it elicits unwanted side effects, particularly in neuronal cells, remains to be fully elucidated. The Lkb1-p53-p21 signalling pathway is able to modulate neuronal self‑renewal and proliferation. Furthermore, the suppression of Lkb1‑dependent p21 induction leads to apoptosis. In the present study, whether Lkb1‑p53‑p21 signalling is involved in the response to isoflurane was investigated. A comparison of mouse primary, wild‑type neural stem cells (WT NSCs) with the p53‑/‑ NSC cell line, NE‑4C, revealed that isoflurane inhibited proliferation in a dose‑, a time‑ and a p53‑dependent manner. However, flow cytometric analysis revealed that the concentration of isoflurane which caused 50% inhibition (the IC50 value) induced cell cycle arrest in WT NSCs. Furthermore, the protein expression levels of LKB1, p53 and p21 were increased, although those of nestin and survivin decreased, following treatment of WT NSCs with isoflurane. On the other hand, isoflurane induced the phosphorylation of Ser15 in p53 in WT NSCs, which was associated with p53 binding to the p21 promoter, and consequentially, the transcriptional activation of p21. All these events were abrogated in NE‑4C cells. Taken together, the present study has demonstrated that isoflurane suppresses the self-renewal of normal mouse NSCs by activating the Lkb1-p53-p21 signalling pathway.

  9. Harnessing endogenous stem/progenitor cells for tendon regeneration

    PubMed Central

    Lee, Chang H.; Lee, Francis Y.; Tarafder, Solaiman; Kao, Kristy; Jun, Yena; Yang, Guodong; Mao, Jeremy J.

    2015-01-01

    Current stem cell–based strategies for tissue regeneration involve ex vivo manipulation of these cells to confer features of the desired progenitor population. Recently, the concept that endogenous stem/progenitor cells could be used for regenerating tissues has emerged as a promising approach that potentially overcomes the obstacles related to cell transplantation. Here we applied this strategy for the regeneration of injured tendons in a rat model. First, we identified a rare fraction of tendon cells that was positive for the known tendon stem cell marker CD146 and exhibited clonogenic capacity, as well as multilineage differentiation ability. These tendon-resident CD146+ stem/progenitor cells were selectively enriched by connective tissue growth factor delivery (CTGF delivery) in the early phase of tendon healing, followed by tenogenic differentiation in the later phase. The time-controlled proliferation and differentiation of CD146+ stem/progenitor cells by CTGF delivery successfully led to tendon regeneration with densely aligned collagen fibers, normal level of cellularity, and functional restoration. Using siRNA knockdown to evaluate factors involved in tendon generation, we demonstrated that the FAK/ERK1/2 signaling pathway regulates CTGF-induced proliferation and differentiation of CD146+ stem/progenitor cells. Together, our findings support the use of endogenous stem/progenitor cells as a strategy for tendon regeneration without cell transplantation and suggest this approach warrants exploration in other tissues. PMID:26053662

  10. Plasticity of hematopoietic stem cells.

    PubMed

    Ogawa, Makio; LaRue, Amanda C; Mehrotra, Meenal

    2015-01-01

    Almost two decades ago, a number of cell culture and preclinical transplantation studies suggested the striking concept of the tissue-reconstituting ability of hematopoietic stem cells (HSCs). While this heralded an exciting time of radically new therapies for disorders of many organs and tissues, the concept was soon mired by controversy and remained dormant. This chapter provides a brief review of evidence for HSC plasticity including our findings based on single HSC transplantation in mouse. These studies strongly support the concept that HSCs are pluripotent and may be the source for the majority, if not all, of the cell types in our body. PMID:26590762

  11. Klotho, stem cells, and aging

    PubMed Central

    Bian, Ao; Neyra, Javier A; Zhan, Ming; Hu, Ming Chang

    2015-01-01

    Aging is an inevitable and progressive biological process involving dysfunction and eventually destruction of every tissue and organ. This process is driven by a tightly regulated and complex interplay between genetic and acquired factors. Klotho is an antiaging gene encoding a single-pass transmembrane protein, klotho, which serves as an aging suppressor through a wide variety of mechanisms, such as antioxidation, antisenescence, antiautophagy, and modulation of many signaling pathways, including insulin-like growth factor and Wnt. Klotho deficiency activates Wnt expression and activity contributing to senescence and depletion of stem cells, which consequently triggers tissue atrophy and fibrosis. In contrast, the klotho protein was shown to suppress Wnt-signaling transduction, and inhibit cell senescence and preserve stem cells. A better understanding of the potential effects of klotho on stem cells could offer novel insights into the cellular and molecular mechanisms of klotho deficiency-related aging and disease. The klotho protein may be a promising therapeutic agent for aging and aging-related disorders. PMID:26346243

  12. Klotho, stem cells, and aging.

    PubMed

    Bian, Ao; Neyra, Javier A; Zhan, Ming; Hu, Ming Chang

    2015-01-01

    Aging is an inevitable and progressive biological process involving dysfunction and eventually destruction of every tissue and organ. This process is driven by a tightly regulated and complex interplay between genetic and acquired factors. Klotho is an antiaging gene encoding a single-pass transmembrane protein, klotho, which serves as an aging suppressor through a wide variety of mechanisms, such as antioxidation, antisenescence, antiautophagy, and modulation of many signaling pathways, including insulin-like growth factor and Wnt. Klotho deficiency activates Wnt expression and activity contributing to senescence and depletion of stem cells, which consequently triggers tissue atrophy and fibrosis. In contrast, the klotho protein was shown to suppress Wnt-signaling transduction, and inhibit cell senescence and preserve stem cells. A better understanding of the potential effects of klotho on stem cells could offer novel insights into the cellular and molecular mechanisms of klotho deficiency-related aging and disease. The klotho protein may be a promising therapeutic agent for aging and aging-related disorders. PMID:26346243

  13. Klotho, stem cells, and aging.

    PubMed

    Bian, Ao; Neyra, Javier A; Zhan, Ming; Hu, Ming Chang

    2015-01-01

    Aging is an inevitable and progressive biological process involving dysfunction and eventually destruction of every tissue and organ. This process is driven by a tightly regulated and complex interplay between genetic and acquired factors. Klotho is an antiaging gene encoding a single-pass transmembrane protein, klotho, which serves as an aging suppressor through a wide variety of mechanisms, such as antioxidation, antisenescence, antiautophagy, and modulation of many signaling pathways, including insulin-like growth factor and Wnt. Klotho deficiency activates Wnt expression and activity contributing to senescence and depletion of stem cells, which consequently triggers tissue atrophy and fibrosis. In contrast, the klotho protein was shown to suppress Wnt-signaling transduction, and inhibit cell senescence and preserve stem cells. A better understanding of the potential effects of klotho on stem cells could offer novel insights into the cellular and molecular mechanisms of klotho deficiency-related aging and disease. The klotho protein may be a promising therapeutic agent for aging and aging-related disorders.

  14. Combination Cell Therapy with Mesenchymal Stem Cells and Neural Stem Cells for Brain Stroke in Rats

    PubMed Central

    Hosseini, Seyed Mojtaba; Farahmandnia, Mohammad; Razi, Zahra; Delavari, Somayeh; Shakibajahromi, Benafsheh; Sarvestani, Fatemeh Sabet; Kazemi, Sepehr; Semsar, Maryam

    2015-01-01

    Objectives Brain stroke is the second most important events that lead to disability and morbidity these days. Although, stroke is important, there is no treatment for curing this problem. Nowadays, cell therapy has opened a new window for treating central nervous system disease. In some previous studies the Mesenchymal stem cells and neural stem cells. In this study, we have designed an experiment to assess the combination cell therapy (Mesenchymal and Neural stem cells) effects on brain stroke. Method and Materials The Mesenchymal stem cells were isolated from adult rat bone marrow and the neural stem cells were isolated from ganglion eminence of rat embryo 14 days. The Mesenchymal stem cells were injected 1 day after middle cerebral artery occlusion (MCAO) and the neural stem cells transplanted 7 day after MCAO. After 28 days, the neurological outcomes and brain lesion volumes were evaluated. Also, the activity of Caspase 3 was assessed in different groups. Result The group which received combination cell therapy had better neurological examination and less brain lesion. Also the combination cell therapy group had the least Caspase 3 activity among the groups. Conclusions The combination cell therapy is more effective than Mesenchymal stem cell therapy and neural stem cell therapy separately in treating the brain stroke in rats. PMID:26019759

  15. 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.

  16. Anionic polymers and 10 nm Fe₃O₄@UA wound dressings support human foetal stem cells normal development and exhibit great antimicrobial properties.

    PubMed

    Grumezescu, Alexandru Mihai; Holban, Alina Maria; Andronescu, Ecaterina; Mogoşanu, George Dan; Vasile, Bogdan Stefan; Chifiriuc, Mariana Carmen; Lazar, Veronica; Andrei, Eugen; Constantinescu, Andrei; Maniu, Horia

    2014-03-25

    The aims of this study were the development, characterization and bioevaluation of a novel biocompatible, resorbable and bio-active wound dressing prototype, based on anionic polymers (sodium alginate--AlgNa, carboximethylcellulose--CMC) and magnetic nanoparticles loaded with usnic acid (Fe₃O₄@UA). The antimicrobial activity was tested against Staphylococcus aureus grown in biofilms. The biocompatibility testing model included an endothelial cell line from human umbilical vein and human foetal progenitor cells derived from the amniotic fluid, that express a wide spectrum of surface molecules involved in different vascular functions and inflammatory response, and may be used as skin regenerative support. The obtained results demonstrated that CMC/Fe₃O₄@UA and AlgNa/Fe₃O₄@UA are exhibiting structural and functional properties that recommend them for further applications in the biomedical field. They could be used alone or coated with different bio-active compounds, such as Fe₃O₄@UA, for the development of novel, multifunctional porous materials used in tissues regeneration, as antimicrobial substances releasing devices, providing also a mechanical support for the eukaryotic cells adhesion, and exhibiting the advantage of low cytotoxicity on human progenitor cells. The great antimicrobial properties exhibited by the newly synthesized nano-bioactive coatings are recommending them as successful candidates for improving the implanted devices surfaces used in regenerative medicine. PMID:23994366

  17. Anionic polymers and 10 nm Fe₃O₄@UA wound dressings support human foetal stem cells normal development and exhibit great antimicrobial properties.

    PubMed

    Grumezescu, Alexandru Mihai; Holban, Alina Maria; Andronescu, Ecaterina; Mogoşanu, George Dan; Vasile, Bogdan Stefan; Chifiriuc, Mariana Carmen; Lazar, Veronica; Andrei, Eugen; Constantinescu, Andrei; Maniu, Horia

    2014-03-25

    The aims of this study were the development, characterization and bioevaluation of a novel biocompatible, resorbable and bio-active wound dressing prototype, based on anionic polymers (sodium alginate--AlgNa, carboximethylcellulose--CMC) and magnetic nanoparticles loaded with usnic acid (Fe₃O₄@UA). The antimicrobial activity was tested against Staphylococcus aureus grown in biofilms. The biocompatibility testing model included an endothelial cell line from human umbilical vein and human foetal progenitor cells derived from the amniotic fluid, that express a wide spectrum of surface molecules involved in different vascular functions and inflammatory response, and may be used as skin regenerative support. The obtained results demonstrated that CMC/Fe₃O₄@UA and AlgNa/Fe₃O₄@UA are exhibiting structural and functional properties that recommend them for further applications in the biomedical field. They could be used alone or coated with different bio-active compounds, such as Fe₃O₄@UA, for the development of novel, multifunctional porous materials used in tissues regeneration, as antimicrobial substances releasing devices, providing also a mechanical support for the eukaryotic cells adhesion, and exhibiting the advantage of low cytotoxicity on human progenitor cells. The great antimicrobial properties exhibited by the newly synthesized nano-bioactive coatings are recommending them as successful candidates for improving the implanted devices surfaces used in regenerative medicine.

  18. Stem Cells News Update: A Personal Perspective

    PubMed Central

    Wong, SC

    2013-01-01

    This article is a follow-up to a previous Commentary published in 2011. It updates some of the events mentioned in that Commentary and continues with more interesting and exciting news on stem cell research and the emerging field of Regenerative Medicine. Some of the news includes: 1) the 2012 Nobel Prize for Medicine awarded to John B. Gurdon and Shinya Yamanaka; 2) the cloning of human embryonic stem cells; 3) the continued search for truly pluripotent adult stem cells via in vitro and in vivo protocols; 4) the breakthrough in organ replacements; 5) the global stem cell race; 6) the global stem cell cryo-preservation business; 7) the worldwide stem cell donor registries, and 8) the issue of government regulation on stem cell therapy. PMID:24778557

  19. [Stem cells and tissue engineering techniques].

    PubMed

    Sica, Gigliola

    2013-01-01

    The therapeutic use of stem cells and tissue engineering techniques are emerging in urology. Here, stem cell types, their differentiating potential and fundamental characteristics are illustrated. The cancer stem cell hypothesis is reported with reference to the role played by stem cells in the origin, development and progression of neoplastic lesions. In addition, recent reports of results obtained with stem cells alone or seeded in scaffolds to overcome problems of damaged urinary tract tissue are summarized. Among others, the application of these biotechnologies in urinary bladder, and urethra are delineated. Nevertheless, apart from the ethical concerns raised from the use of embryonic stem cells, a lot of questions need to be solved concerning the biology of stem cells before their widespread use in clinical trials. Further investigation is also required in tissue engineering utilizing animal models.

  20. Stem cell facelift: between reality and fiction.

    PubMed

    Atiyeh, Bishara S; Ibrahim, Amir E; Saad, Dibo A

    2013-03-01

    Stem cells are "big business" throughout medical technology, and their potential application in cosmetic procedures is no exception. One of the latest nonsurgical facial treatments (and new catchphrases) in plastic surgery is the "stem cell facelift." It is evident from the currently available scientific literature that the use of stem cell therapy for facial rejuvenation is limited to the theoretical induction of skin tightening and can in no way be equated to a facelift. In fact, what is advertised and promoted as a new and original technique of stem cell facelifting is mostly stem cell-enriched lipofilling. Despite encouraging data suggesting that adult stem cells hold promise for future applications, the data from clinical evidence available today do not substantiate the marketing and promotional claims being made to patients. To claim that the "stem cell facelift" is a complete facial rejuvenation procedure surgery is unethical.

  1. Stem cells news update: a personal perspective.

    PubMed

    Wong, Sc

    2013-12-01

    This article is a follow-up to a previous Commentary published in 2011. It updates some of the events mentioned in that Commentary and continues with more interesting and exciting news on stem cell research and the emerging field of Regenerative Medicine. Some of the news includes: 1) the 2012 Nobel Prize for Medicine awarded to John B. Gurdon and Shinya Yamanaka; 2) the cloning of human embryonic stem cells; 3) the continued search for truly pluripotent adult stem cells via in vitro and in vivo protocols; 4) the breakthrough in organ replacements; 5) the global stem cell race; 6) the global stem cell cryo-preservation business; 7) the worldwide stem cell donor registries, and 8) the issue of government regulation on stem cell therapy.

  2. Stem cell facelift: between reality and fiction.

    PubMed

    Atiyeh, Bishara S; Ibrahim, Amir E; Saad, Dibo A

    2013-03-01

    Stem cells are "big business" throughout medical technology, and their potential application in cosmetic procedures is no exception. One of the latest nonsurgical facial treatments (and new catchphrases) in plastic surgery is the "stem cell facelift." It is evident from the currently available scientific literature that the use of stem cell therapy for facial rejuvenation is limited to the theoretical induction of skin tightening and can in no way be equated to a facelift. In fact, what is advertised and promoted as a new and original technique of stem cell facelifting is mostly stem cell-enriched lipofilling. Despite encouraging data suggesting that adult stem cells hold promise for future applications, the data from clinical evidence available today do not substantiate the marketing and promotional claims being made to patients. To claim that the "stem cell facelift" is a complete facial rejuvenation procedure surgery is unethical. PMID:23417722

  3. Tie-mediated signal from apoptotic cells protects stem cells in Drosophila melanogaster.

    PubMed

    Xing, Yalan; Su, Tin Tin; Ruohola-Baker, Hannele

    2015-01-01

    Many types of normal and cancer stem cells are resistant to killing by genotoxins, but the mechanism for this resistance is poorly understood. Here we show that adult stem cells in Drosophila melanogaster germline and midgut are resistant to ionizing radiation (IR) or chemically induced apoptosis and dissect the mechanism for this protection. We find that upon IR the receptor tyrosine kinase Tie/Tie-2 is activated, leading to the upregulation of microRNA bantam that represses FOXO-mediated transcription of pro-apoptotic Smac/DIABLO orthologue, Hid in germline stem cells. Knockdown of the IR-induced putative Tie ligand, Pvf1, a functional homologue of human Angiopoietin, in differentiating daughter cells renders germline stem cells sensitive to IR, suggesting that the dying daughters send a survival signal to protect their stem cells for future repopulation of the tissue. If conserved in cancer stem cells, this mechanism may provide therapeutic options for the eradication of cancer. PMID:25959206

  4. Different Effects of BORIS/CTCFL on Stemness Gene Expression, Sphere Formation and Cell Survival in Epithelial Cancer Stem Cells.

    PubMed

    Alberti, Loredana; Losi, Lorena; Leyvraz, Serge; Benhattar, Jean

    2015-01-01

    Cancer stem cells are cancer cells characterized by stem cell properties and represent a small population of tumor cells that drives tumor development, progression, metastasis and drug resistance. To date, the molecular mechanisms that generate and regulate cancer stem cells are not well defined. BORIS (Brother of Regulator of Imprinted Sites) or CTCFL (CTCF-like) is a DNA-binding protein that is expressed in normal tissues only in germ cells and is re-activated in tumors. Recent evidences have highlighted the correlation of BORIS/CTCFL expression with poor overall survival of different cancer patients. We have previously shown an association of BORIS-expressing cells with stemness gene expression in embryonic cancer cells. Here, we studied the role of BORIS in epithelial tumor cells. Using BORIS-molecular beacon that was already validated, we were able to show the presence of BORIS mRNA in cancer stem cell-enriched populations (side population and spheres) of cervical, colon and breast tumor cells. BORIS silencing studies showed a decrease of sphere formation capacity in breast and colon tumor cells. Importantly, BORIS-silencing led to down-regulation of hTERT, stem cell (NANOG, OCT4, SOX2 and BMI1) and cancer stem cell markers (ABCG2, CD44 and ALDH1) genes. Conversely, BORIS-induction led to up-regulation of the same genes. These phenotypes were observed in cervical, colon and invasive breast tumor cells. However, a completely different behavior was observed in the non-invasive breast tumor cells (MCF7). Indeed, these cells acquired an epithelial mesenchymal transition phenotype after BORIS silencing. Our results demonstrate that BORIS is associated with cancer stem cell-enriched populations of several epithelial tumor cells and the different phenotypes depend on the origin of tumor cells.

  5. Stem Cells, Science, and Public Reasoning

    ERIC Educational Resources Information Center

    Hurlbut, J. Benjamin; Robert, Jason Scott

    2012-01-01

    These are interesting days in the scientific, social, and political debates about human embryonic stem cell research. Pluripotent stem cells--cells that can, in principle, give rise to the body's full range of cell types--were previously derivable only from human embryos that were destroyed in the process. Now, a variety of somatic cell types can…

  6. Cancer Stem Cells Converted from Pluripotent Stem Cells and the Cancerous Niche

    PubMed Central

    Kasai, T; Chen, L; Mizutani, AZ; Kudoh, T; Murakami, H; Fu, L; Seno, M

    2014-01-01

    Nowadays, the cancer stem cells are considered to be significantly responsible for growth, metastasis, invasion and recurrence of all cancer. Cancer stem cells are typically characterized by continuous proliferation and self-renewal as well as by differentiation potential, while stem cells are considered to differentiate into tissue- specific phenotype of mature cells under the influence of micro-environment. Cancer stem cells should be traced to the stem cells under the influence of a micro-environment, which induces malignant tumors. In this review, we propose this micro-environment as a ‘cancerous niche’ and discuss its importance on the formation and maintenance of cancer stem cells with the recent experimental results to establish cancer stem cell models from induced pluripotent stem cells. These models of cancer stem cell will provide the great advantages in cancer research and its therapeutic applications in the future. PMID:25075155

  7. Learning about Cancer by Studying Stem Cells

    MedlinePlus

    ... About Cancer by Studying Stem Cells Inside Life Science View All Articles | Inside Life Science Home Page Learning About Cancer by Studying Stem ... Once Upon a Stem Cell This Inside Life Science article also appears on LiveScience . Learn about related ...

  8. Stem cells shine in Shanghai.

    PubMed

    Cheng, Linzhao; Xiao, Lei; Zeng, Fanyi; Zhang, Y Alex

    2008-01-10

    From November 6 to 9, 2007, more than 500 scientists from 20 countries and regions gathered in Shanghai, China, to attend the 2007 Shanghai International Symposium on Stem Cell Research. This dynamic meeting was jointly organized by the International Society for Stem Cell Research (ISSCR), the Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences (SIBS/CAS), and other institutes in China. For the first time, the ISSCR added its name to a conference other than its own annual meeting, embracing this opportunity to learn more about research that is happening in China and providing a platform for local researchers who do not always have the opportunity to travel internationally to the ISSCR annual meetings. Here we present a sampling of the diverse research presented by the local and international participants during the science-packed 4 day meeting.

  9. Adult stem cells and tissue repair.

    PubMed

    Körbling, M; Estrov, Z; Champlin, R

    2003-08-01

    Recently, adult stem cells originating from bone marrow or peripheral blood have been suggested to contribute to repair and genesis of cells specific for liver, cardiac and skeletal muscle, gut, and brain tissue. The mechanism involved has been termed transdifferentiation, although other explanations including cell fusion have been postulated. Using adult stem cells to generate or repair solid organ tissue obviates the immunologic, ethical, and teratogenic issues that accompany embryonic stem cells.

  10. Cancer stem cells and metastasis.

    PubMed

    Sampieri, Katia; Fodde, Riccardo

    2012-06-01

    Cancer stem cells (CSCs) represent a subpopulation of tumour cells endowed with self-renewal and multi-lineage differentiation capacity but also with an innate resistance to cytotoxic agents, a feature likely to pose major clinical challenges towards the complete eradication of minimal residual disease in cancer patients. Operationally, CSCs are defined by their tumour-propagating ability when serially transplanted into immune-compromised mice and by their capacity to fully recapitulate the original heterogeneity of cell types observed in the primary lesions they are derived from. CSCs were first identified in haematopoietic malignancies and later in a broad spectrum of solid tumours including those of the breast, colon and brain. Notably, several CSC characteristics are relevant to metastasis, such as motility, invasiveness and, as mentioned above, resistance to DNA damage-induced apoptosis. Here, we have reviewed the current literature on the relation between CSCs and metastasis formation. Preliminary studies on cancer cell lines and patient-derived material suggest a rate-limiting role for stem-like cells in the processes of tumour cell dissemination and metastasis formation. However, additional studies are needed to deliver formal proof of their identity as the cell of origin of recurrences at distant organ sites. Nevertheless, several studies have already provided pre-clinical evidence of the efficacy of novel therapies directed against disseminated CSCs.

  11. ZO-1 and ZO-2 are required for extra-embryonic endoderm integrity, primitive ectoderm survival and normal cavitation in embryoid bodies derived from mouse embryonic stem cells.

    PubMed

    Phua, Dominic C Y; Xu, Jianliang; Ali, Safiah Mohamed; Boey, Adrian; Gounko, Natalia V; Hunziker, Walter

    2014-01-01

    The Zonula Occludens proteins ZO-1 and ZO-2 are cell-cell junction-associated adaptor proteins that are essential for the structural and regulatory functions of tight junctions in epithelial cells and their absence leads to early embryonic lethality in mouse models. Here, we use the embryoid body, an in vitro peri-implantation mouse embryogenesis model, to elucidate and dissect the roles ZO-1 and ZO-2 play in epithelial morphogenesis and de novo tight junction assembly. Through the generation of individual or combined ZO-1 and ZO-2 null embryoid bodies, we show that their dual deletion prevents tight junction formation, resulting in the disorganization and compromised barrier function of embryoid body epithelial layers. The disorganization is associated with poor microvilli development, fragmented basement membrane deposition and impaired cavity formation, all of which are key epithelial tissue morphogenetic processes. Expression of Podocalyxin, which positively regulates the formation of microvilli and the apical membrane, is repressed in embryoid bodies lacking both ZO-1 and ZO-2 and this correlates with an aberrant submembranous localization of Ezrin. The null embryoid bodies thus give an insight into how the two ZO proteins influence early mouse embryogenesis and possible mechanisms underlying the embryonic lethal phenotype.

  12. ZO-1 and ZO-2 Are Required for Extra-Embryonic Endoderm Integrity, Primitive Ectoderm Survival and Normal Cavitation in Embryoid Bodies Derived from Mouse Embryonic Stem Cells

    PubMed Central

    Ali, Safiah Mohamed; Boey, Adrian; Gounko, Natalia V.; Hunziker, Walter

    2014-01-01

    The Zonula Occludens proteins ZO-1 and ZO-2 are cell-cell junction-associated adaptor proteins that are essential for the structural and regulatory functions of tight junctions in epithelial cells and their absence leads to early embryonic lethality in mouse models. Here, we use the embryoid body, an in vitro peri-implantation mouse embryogenesis model, to elucidate and dissect the roles ZO-1 and ZO-2 play in epithelial morphogenesis and de novo tight junction assembly. Through the generation of individual or combined ZO-1 and ZO-2 null embryoid bodies, we show that their dual deletion prevents tight junction formation, resulting in the disorganization and compromised barrier function of embryoid body epithelial layers. The disorganization is associated with poor microvilli development, fragmented basement membrane deposition and impaired cavity formation, all of which are key epithelial tissue morphogenetic processes. Expression of Podocalyxin, which positively regulates the formation of microvilli and the apical membrane, is repressed in embryoid bodies lacking both ZO-1 and ZO-2 and this correlates with an aberrant submembranous localization of Ezrin. The null embryoid bodies thus give an insight into how the two ZO proteins influence early mouse embryogenesis and possible mechanisms underlying the embryonic lethal phenotype. PMID:24905925

  13. Generalized Potential of Adult Neural Stem Cells

    NASA Astrophysics Data System (ADS)

    Clarke, Diana L.; Johansson, Clas B.; Wilbertz, Johannes; Veress, Biborka; Nilsson, Erik; Karlström, Helena; Lendahl, Urban; Frisén, Jonas

    2000-06-01

    The differentiation potential of stem cells in tissues of the adult has been thought to be limited to cell lineages present in the organ from which they were derived, but there is evidence that some stem cells may have a broader differentiation repertoire. We show here that neural stem cells from the adult mouse brain can contribute to the formation of chimeric chick and mouse embryos and give rise to cells of all germ layers. This demonstrates that an adult neural stem cell has a very broad developmental capacity and may potentially be used to generate a variety of cell types for transplantation in different diseases.

  14. Mesenchymal Stem Cells in Hematopoietic Stem Cell Transplantation

    PubMed Central

    Battiwalla, Minoo; Hematti, Peiman

    2009-01-01

    Mesenchymal stromal/stem cells (MSCs) of bone marrow (BM) origin not only provide the supportive microenvironmental niche for hematopoietic stem cells (HSCs) but are also capable of differentiating into various cell types of mesenchymal origin, such as bone, fat, and cartilage. In vitro and in vivo data suggest that MSCs have low inherent immunogenicity, modulate/suppress immunological responses through interactions with immune cells, and home to damaged tissues to participate in regeneration processes through their diverse biological properties. MSCs derived from BM are being evaluated for a wide range of clinical applications including disorders as diverse as myocardial infarction or newly diagnosed diabetes mellitus type-1. However, their use in HSC transplantation, either for enhancement of hematopoietic engraftment or for treatment/prevention of graft versus host disease, is far ahead of other indications. Ease of isolation and ex vivo expansion of MSCs, combined with their intriguing immunomodulatory properties, and their impressive record of safety in a wide variety of clinical trials make these cells promising candidates for further investigation. PMID:19728189

  15. CANCER STEM CELLS AND RADIORESISTANCE

    PubMed Central

    K, Rycaj; D.G, Tang

    2015-01-01

    Purpose Radiation therapy has made significant contributions to cancer therapy. However, despite continuous improvements, tumor recurrence and therapy resistance still occur in a high proportion of patients. One underlying reason for this radioresistance might be attributable to the presence of cancer stem cells (CSCs). Conclusions This review discusses CSC-specific mechanisms that confer radiation resistance with a focus on breast cancer and glioblastoma multiforme (GBM), thereby emphasizing the addition of these potential therapeutic targets in order to potentiate radiotherapy efficacy. PMID:24527669

  16. Stem cells - biological update and cell therapy progress.

    PubMed

    Girlovanu, Mihai; Susman, Sergiu; Soritau, Olga; Rus-Ciuca, Dan; Melincovici, Carmen; Constantin, Anne-Marie; Mihu, Carmen Mihaela

    2015-01-01

    In recent years, the advances in stem cell research have suggested that the human body may have a higher plasticity than it was originally expected. Until now, four categories of stem cells were isolated and cultured in vivo: embryonic stem cells, fetal stem cells, adult stem cells and induced pluripotent stem cells (hiPSCs). Although multiple studies were published, several issues concerning the stem cells are still debated, such as: the molecular mechanisms of differentiation, the methods to prevent teratoma formation or the ethical and religious issues regarding especially the embryonic stem cell research. The direct differentiation of stem cells into specialized cells: cardiac myocytes, neural cells, pancreatic islets cells, may represent an option in treating incurable diseases such as: neurodegenerative diseases, type I diabetes, hematologic or cardiac diseases. Nevertheless, stem cell-based therapies, based on stem cell transplantation, remain mainly at the experimental stages and their major limitation is the development of teratoma and cancer after transplantation. The induced pluripotent stem cells (hiPSCs) represent a prime candidate for future cell therapy research because of their significant self-renewal and differentiation potential and the lack of ethical issues. This article presents an overview of the biological advances in the study of stem cells and the current progress made in the field of regenerative medicine.

  17. The Role of MicroRNAs in Cardiac Stem Cells

    PubMed Central

    Purvis, Nima; Bahn, Andrew; Katare, Rajesh

    2015-01-01

    Stem cells are considered as the next generation drug treatment in patients with cardiovascular disease who are resistant to conventional treatment. Among several stem cells used in the clinical setting, cardiac stem cells (CSCs) which reside in the myocardium and epicardium of the heart have been shown to be an effective option for the source of stem cells. In normal circumstances, CSCs primarily function as a cell store to replace the physiologically depleted cardiovascular cells, while under the diseased condition they have been shown to experimentally regenerate the diseased myocardium. In spite of their major functional role, molecular mechanisms regulating the CSCs proliferation and differentiation are still unknown. MicroRNAs (miRs) are small, noncoding RNA molecules that regulate gene expression at the posttranscriptional level. Recent studies have demonstrated the important role of miRs in regulating stem cell proliferation and differentiation, as well as other physiological and pathological processes related to stem cell function. This review summarises the current understanding of the role of miRs in CSCs. A deeper understanding of the mechanisms by which miRs regulate CSCs may lead to advances in the mode of stem cell therapies for the treatment of cardiovascular diseases. PMID:25802528

  18. Stem cell tracking with optically active nanoparticles

    PubMed Central

    Gao, Yu; Cui, Yan; Chan, Jerry KY; Xu, Chenjie

    2013-01-01

    Stem-cell-based therapies hold promise and potential to address many unmet clinical needs. Cell tracking with modern imaging modalities offers insight into the underlying biological process of the stem-cell-based therapies, with the goal to reveal cell survival, migration, homing, engraftment, differentiation, and functions. Adaptability, sensitivity, resolution, and non-invasiveness have contributed to the longstanding use of optical imaging for stem cell tracking and analysis. To identify transplanted stem cells from the host tissue, optically active probes are usually used to label stem cells before the administration. In comparison to the traditional fluorescent probes like fluorescent proteins and dyes, nanoparticle-based probes are advantageous in terms of the photo-stabilities and minimal changes to the cell phenotype. The main focus here is to overview the recent development of optically active nanoparticles for stem cells tracking. The related optical imaging modalities include fluorescence imaging, photoacoustic imaging, Raman and surface enhanced Raman spectroscopy imaging. PMID:23638335

  19. Antiproliferative Effects of Mesenchymal Stem Cells and Epithelial Cells on Lymphocytes.

    PubMed

    Svirshchevskaya, E V; Poltavtseva, R A; Beletskii, I P; Selezneva, I I; Sukhikh, G T

    2016-08-01

    We analyzed the interactions between peripheral blood lymphocytes from heterologous donors with mesenchymal stem cells obtained from the tooth pulp and trophoblast. In mixed cultures, proliferation of both lymphocytes and mesenchymal stem cells was suppressed. Similar suppressive effects were observed in lymphocyte cultures mixed with epithelial cells (hepatocytes HeG2 and renal epithelial cells HEK293). This suppression can be determined by impairment of normal adhesion contacts between cells of different origin. PMID:27590756

  20. Stem cell programs are retained in human leukemic lymphoblasts.

    PubMed

    Fan, D; Zhou, X; Li, Z; Li, Z-Q; Duan, C; Liu, T; Zhang, F; Huang, Y; Zhang, Y; Gao, F; Guo, Y; Gupta, R; Chen, G; Enver, T; Tang, J; Hong, D

    2015-04-16

    Leukemic lymphoblasts within different immunophenotypic populations possess stem cell properties. However, whether or not the self-renewal program is retained from stem cells or conferred on progenitors by leukemogenic molecules remains unknown. We have addressed the issue in the context of TEL-AML1-associated acute lymphoblastic leukemia (ALL) by profiling a refined program edited from genes essential for self-renewal of hematopoietic stem cells and B-cell development. Bioinformatic analysis shows that ALL populations are loosely clustered and close to the normal population that contains stem and primitive progenitor cells. This finding indicates that immunophenotypes do not reflect maturation stages in ALL and that the self-renewal program may be retained from stem cells. Results of assessing 'first hit' function of TEL-AML1 in different populations of normal cells demonstrate the molecular model. Therefore, the current study shows a leukemogenic scenario of human ALL in which programs of stem cells are sustained in distinct fractions by leukemogenic mutations.

  1. Cellular origin of cancer: dedifferentiation or stem cell maturation arrest?

    PubMed Central

    Sell, S

    1993-01-01

    Given the fundamental principle that cancer must arise from a cell that has the potential to divide, two major nonexclusive hypotheses of the cellular origin of cancer are that malignancy arises a) from stem cells due to maturation arrest or b) from dedifferentiation of mature cells that retain the ability to proliferate. The role of stem cells in carcinogenesis is clearly demonstrated in teratocarcinomas. The malignant stem cells of teratocarcinomas are derived from normal multipotent stem cells and have the potential to differentiate into normal benign mature tissue. A widely studied model supporting dedifferentiation has been the putative origin of hepatocarcinomas from "premalignant" foci and nodules induced in the rat liver by chemicals. However, the dedifferentiation concept for hepatocarcinogenesis is challenged by more recent interpretations indicating that hepatocellular carcinoma arises from maturation arrest caused by aberrant differentiation of determined stem cells. Either hypothesis is supported by the cellular changes that occur in the rodent liver after different hepatocarcinogenic regimens. The formation of foci and nodules from altered hepatocytes supports dedifferentiation; the proliferation of small oval cells with the potential to differentiate into either biliary ducts or hepatocytes supports arrested maturation of determined stem cells. It is now postulated that foci and nodular change reflect adaptive changes to the toxic effects of carcinogens and not "preneoplastic" stages to cancer. The stem cell model predicts that genotoxic chemicals induce mutations in the determined stem cell which may be expressed in its progeny. Proliferation of initiated cells is induced by promoting events which also allow additional mutations to occur. PMID:7516873

  2. Brain tumour stem cells: possibilities of new therapeutic strategies.

    PubMed

    Piccirillo, Sara G M; Vescovi, Angelo L

    2007-08-01

    Cancers are composed of heterogeneous cell populations, including highly proliferative immature precursors and differentiated cells, which may belong to different lineages. Recent advances in stem cell research have demonstrated the existence of tumour-initiating, cancer stem cells (CSCs) in non-solid and solid tumours. These cells are defined as CSCs because they show functional properties that resemble those of their normal counterpart to a significant extent. This concept applies to CSCs from brain tumours and, particularly, to glioblastoma stem-like cells, which self-renew under clonal conditions and differentiate into neuron- and glia-like cells, and into aberrant cells, with mixed neuronal/astroglia phenotypes. Notably, across serial transplantation into immunodeficient mice, glioblastoma stem-like cells are able to form secondary tumours which are a phenocopy of the human disease. A significant effort is underway to identify both CSC-specific markers and the molecular mechanism that underpin the tumorigenic potential of these cells, for this will have a critical impact on the understanding of the origin of malignant brain tumour and the discovery of new and more specific therapeutic approaches. Lately, the authors have shown that some of the bone morphogenetic proteins can reduce the tumorigenic ability of CSCs in GBMs. This suggests that mechanisms regulating the physiology of normal brain stem cells may be still in place in their cancerous siblings and that this may lead to the development of cures that selectively target the population CSCs found in the patients' tumour mass.

  3. Stem cells in the nervous system.

    PubMed

    Maldonado-Soto, Angel R; Oakley, Derek H; Wichterle, Hynek; Stein, Joel; Doetsch, Fiona K; Henderson, Christopher E

    2014-11-01

    Given their capacity to regenerate cells lost through injury or disease, stem cells offer new vistas into possible treatments for degenerative diseases and their underlying causes. As such, stem cell biology is emerging as a driving force behind many studies in regenerative medicine. This review focuses on the current understanding of the applications of stem cells in treating ailments of the human brain, with an emphasis on neurodegenerative diseases. Two types of neural stem cells are discussed: endogenous neural stem cells residing within the adult brain and pluripotent stem cells capable of forming neural cells in culture. Endogenous neural stem cells give rise to neurons throughout life, but they are restricted to specialized regions in the brain. Elucidating the molecular mechanisms regulating these cells is key in determining their therapeutic potential as well as finding mechanisms to activate dormant stem cells outside these specialized microdomains. In parallel, patient-derived stem cells can be used to generate neural cells in culture, providing new tools for disease modeling, drug testing, and cell-based therapies. Turning these technologies into viable treatments will require the integration of basic science with clinical skills in rehabilitation.

  4. Stem Cells in the Nervous System

    PubMed Central

    Maldonado-Soto, Angel R.; Oakley, Derek H.; Wichterle, Hynek; Stein, Joel; Doetsch, Fiona K.; Henderson, Christopher E.

    2014-01-01

    Given their capacity to regenerate cells lost through injury or disease, stem cells offer new vistas into possible treatments for degenerative diseases and their underlying causes. As such, stem cell biology is emerging as a driving force behind many studies in the field of regenerative medicine. This review focuses on our current understanding of the applications of stem cells in treating ailments of the human brain, with an emphasis on neurodegenerative diseases. Two types of neural stem cells are discussed: endogenous neural stem cells residing within the adult brain, and pluripotent stem cells capable of forming neural cells in culture. Endogenous neural stem cells give rise to neurons throughout life, but they are restricted to specialized regions in the brain. Elucidating the molecular mechanisms regulating these cells is key in determining their therapeutic potential, as well as finding mechanisms to activate dormant stem cells outside of these specialized microdomains. In parallel, patient-derived stem cells can be used to generate neural cells in culture, providing new tools for disease modeling, drug testing and cell-based therapies. Turning these technologies into viable treatments will require the integration of basic science with clinical skills in rehabilitation. PMID:24800720

  5. Engineering Stem Cells for Biomedical Applications.

    PubMed

    Yin, Perry T; Han, Edward; Lee, Ki-Bum

    2016-01-01

    Stem cells are characterized by a number of useful properties, including their ability to migrate, differentiate, and secrete a variety of therapeutic molecules such as immunomodulatory factors. As such, numerous pre-clinical and clinical studies have utilized stem cell-based therapies and demonstrated their tremendous potential for the treatment of various human diseases and disorders. Recently, efforts have focused on engineering stem cells in order to further enhance their innate abilities as well as to confer them with new functionalities, which can then be used in various biomedical applications. These engineered stem cells can take on a number of forms. For instance, engineered stem cells encompass the genetic modification of stem cells as well as the use of stem cells for gene delivery, nanoparticle loading and delivery, and even small molecule drug delivery. The present Review gives an in-depth account of the current status of engineered stem cells, including potential cell sources, the most common methods used to engineer stem cells, and the utilization of engineered stem cells in various biomedical applications, with a particular focus on tissue regeneration, the treatment of immunodeficiency diseases, and cancer.

  6. Stressed stem cells: Temperature response in aged mesenchymal stem cells.

    PubMed

    Stolzing, Alexandra; Sethe, Sebastian; Scutt, Andrew M

    2006-08-01

    Mesenchymal stem cells (MSCs) derived from young (6 week) and aged (56 week) Wistar rats were cultured at standard (37 degrees C) and reduced (32 degrees C) temperature and compared for age markers and stress levels. (ROS, NO, TBARS, carbonyls, lipofuscin, SOD, GPx, apoptosis, proteasome activity) and heat shock proteins (HSP27, -60, -70, -90). Aged MSCs display many of the stress markers associated with aging in other cell types, but results vary across marker categories and are temperature dependant. In young MSCs, culturing at reduced temperature had a generally beneficial effect: the anti-apoptotic heat shock proteins HSP 27, HSP70, and HSP90 were up-regulated; pro-apoptotic HSP60 was downregulated; SOD, GPx increased; and levels in ROS, NO, TBARS, carbonyl, and lipofuscin were diminished. Apoptosis was reduced, but also proteasome activity. In contrast, in aged MSCs, culturing at reduced temperature generally produced no 'beneficial' changes in these parameters, and can even have detrimental effects. Implications for tissue engineering and for stem cell gerontology are discussed. The results suggest that a 'hormesis' theory of stress response can be extended to MSCs, but that cooling cultivation temperature stress produces positive effects in young cells only.

  7. Mesenchymal stem cell like (MSCl) cells generated from human embryonic stem cells support pluripotent cell growth

    SciTech Connect

    Varga, Nora; Vereb, Zoltan; Rajnavoelgyi, Eva; Nemet, Katalin; Uher, Ferenc; Sarkadi, Balazs; Apati, Agota

    2011-10-28

    Highlights: Black-Right-Pointing-Pointer MSC like cells were derived from hESC by a simple and reproducible method. Black-Right-Pointing-Pointer Differentiation and immunosuppressive features of MSCl cells were similar to bmMSC. Black-Right-Pointing-Pointer MSCl cells as feeder cells support the undifferentiated growth of hESC. -- Abstract: Mesenchymal stem cell like (MSCl) cells were generated from human embryonic stem cells (hESC) through embryoid body formation, and isolated by adherence to plastic surface. MSCl cell lines could be propagated without changes in morphological or functional characteristics for more than 15 passages. These cells, as well as their fluorescent protein expressing stable derivatives, efficiently supported the growth of undifferentiated human embryonic stem cells as feeder cells. The MSCl cells did not express the embryonic (Oct4, Nanog, ABCG2, PODXL, or SSEA4), or hematopoietic (CD34, CD45, CD14, CD133, HLA-DR) stem cell markers, while were positive for the characteristic cell surface markers of MSCs (CD44, CD73, CD90, CD105). MSCl cells could be differentiated toward osteogenic, chondrogenic or adipogenic directions and exhibited significant inhibition of mitogen-activated lymphocyte proliferation, and thus presented immunosuppressive features. We suggest that cultured MSCl cells can properly model human MSCs and be applied as efficient feeders in hESC cultures.

  8. Isolation and Characterization of Pluripotent Human Spermatogonial Stem Cell-Derived Cells

    PubMed Central

    Kossack, Nina; Meneses, Juanito; Shefi, Shai; Nguyen, Ha Nam; Chavez, Shawn; Nicholas, Cory; Gromoll, Joerg; Turek, Paul J; Reijo-Pera, Renee A

    2009-01-01

    Several reports have documented the derivation of pluripotent cells (multipotent germline stem cells) from spermatogonial stem cells obtained from the adult mouse testis. These spermatogonia-derived stem cells express embryonic stem cell markers and differentiate to the three primary germ layers, as well as the germline. Data indicate that derivation may involve reprogramming of endogenous spermatogonia in culture. Here, we report the derivation of human multipotent germline stem cells (hMGSCs) from a testis biopsy. The cells express distinct markers of pluripotency, form embryoid bodies that contain derivatives of all three germ layers, maintain a normal XY karyotype, are hypomethylated at the H19 locus, and express high levels of telomerase. Teratoma assays indicate the presence of human cells 8 weeks post-transplantation but limited teratoma formation. Thus, these data suggest the potential to derive pluripotent cells from human testis biopsies but indicate a need for novel strategies to optimize hMGSC culture conditions and reprogramming. PMID:18927477

  9. Evaluating alternative stem cell hypotheses for adult corneal epithelial maintenance

    PubMed Central

    West, John D; Dorà, Natalie J; Collinson, J Martin

    2015-01-01

    In this review we evaluate evidence for three different hypotheses that explain how the corneal epithelium is maintained. The limbal epithelial stem cell (LESC) hypothesis is most widely accepted. This proposes that stem cells in the basal layer of the limbal epithelium, at the periphery of the cornea, maintain themselves and also produce transient (or transit) amplifying cells (TACs). TACs then move centripetally to the centre of the cornea in the basal layer of the corneal epithelium and also replenish cells in the overlying suprabasal layers. The LESCs maintain the corneal epithelium during normal homeostasis and become more active to repair significant wounds. Second, the corneal epithelial stem cell (CESC) hypothesis postulates that, during normal homeostasis, stem cells distributed throughout the basal corneal epithelium, maintain the tissue. According to this hypothesis, LESCs are present in the limbus but are only active during wound healing. We also consider a third possibility, that the corneal epithelium is maintained during normal homeostasis by proliferation of basal corneal epithelial cells without any input from stem cells. After reviewing the published evidence, we conclude that the LESC and CESC hypotheses are consistent with more of the evidence than the third hypothesis, so we do not consider this further. The LESC and CESC hypotheses each have difficulty accounting for one main type of evidence so we evaluate the two key lines of evidence that discriminate between them. Finally, we discuss how lineage-tracing experiments have begun to resolve the debate in favour of the LESC hypothesis. Nevertheless, it also seems likely that some basal corneal epithelial cells can act as long-term progenitors if limbal stem cell function is compromised. Thus, this aspect of the CESC hypothesis may have a lasting impact on our understanding of corneal epithelial maintenance, even if it is eventually shown that stem cells are restricted to the limbus as proposed

  10. Reforming craniofacial orthodontics via stem cells

    PubMed Central

    Mohanty, Pritam; Prasad, N.K.K.; Sahoo, Nivedita; Kumar, Gunjan; Mohanty, Debapreeti; Sah, Sushila

    2015-01-01

    Stem cells are the most interesting cells in cell biology. They have the potential to evolve as one of the most powerful technologies in the future. The future refers to an age where it will be used extensively in various fields of medical and dental sciences. Researchers have discovered a number of sources from which stem cells can be derived. Craniofacial problems are very common and occur at all ages. Stem cells can be used therapeutically in almost every field of health science. In fact, many procedures will be reformed after stem cells come into play. This article is an insight into the review of the current researches being carried out on stem cells and its use in the field of orthodontics, which is a specialized branch of dentistry. Although the future is uncertain, there is a great possibility that stem cells will be used extensively in almost all major procedures of orthodontics. PMID:25767761

  11. Stem Cells in the Cornea.

    PubMed

    Hertsenberg, Andrew J; Funderburgh, James L

    2015-01-01

    The cornea is the tough, transparent tissue through which light first enters the eye and functions as a barrier to debris and infection as well as two-thirds of the refractive power of the eye. Corneal damage that is not promptly treated will often lead to scarring and vision impairment. Due to the limited options currently available to treat corneal scars, the identification and isolation of stem cells in the cornea has received much attention, as they may have potential for autologous, cell-based approaches to the treatment of damaged corneal tissue.

  12. Stem cell differentiation and human liver disease

    PubMed Central

    Zhou, Wen-Li; Medine, Claire N; Zhu, Liang; Hay, David C

    2012-01-01

    Human stem cells are scalable cell populations capable of cellular differentiation. This makes them a very attractive in vitro cellular resource and in theory provides unlimited amounts of primary cells. Such an approach has the potential to improve our understanding of human biology and treating disease. In the future it may be possible to deploy novel stem cell-based approaches to treat human liver diseases. In recent years, efficient hepatic differentiation from human stem cells has been achieved by several research groups including our own. In this review we provide an overview of the field and discuss the future potential and limitations of stem cell technology. PMID:22563188

  13. Adult Stem Cell Responses to Nanostimuli

    PubMed Central

    Tsimbouri, Penelope M.

    2015-01-01

    Adult or mesenchymal stem cells (MSCs) have been found in different tissues in the body, residing in stem cell microenvironments called “stem cell niches”. They play different roles but their main activity is to maintain tissue homeostasis and repair throughout the lifetime of an organism. Their ability to differentiate into different cell types makes them an ideal tool to study tissue development and to use them in cell-based therapies. This differentiation process is subject to both internal and external forces at the nanoscale level and this response of stem cells to nanostimuli is the focus of this review. PMID:26193326

  14. Stem cells and the Planarian Schmidtea mediterranea.

    PubMed

    Sánchez Alvarado, Alejandro

    2007-01-01

    In recent years, stem cells have been heralded as potential therapeutic agents to address a large number of degenerative diseases. Yet, in order to rationally utilize these cells as effective therapeutic agents, and/or improve treatment of stem-cell-associated malignancies such as leukemias and carcinomas, a better understanding of the basic biological properties of stem cells needs to be acquired. A major limitation in the study of stem cells lies in the difficulty of accessing and studying these cells in vivo. This barrier is further compounded by the limitations of in vitro culture systems, which are unable to emulate the microenvironments in which stem cells reside and which are known to provide critical regulatory signals for their proliferation and differentiation. Given the complexity of vertebrate embryonic and adult stem cell populations and their relative inaccessibility to in vivo molecular analyses, the study of stem cells should benefit from analyzing their counterparts in simpler model organisms. In the past, the use of Drosophila or C. elegans has provided invaluable contributions to our understanding of genes and pathways involved in a variety of human diseases. However, stem cells in these organisms are mostly restricted to the gonads, and more importantly neither Drosophila, nor C. elegans are capable of regenerating body parts lost to injury. Therefore, a simple animal with experimentally accessible stem cells playing a role in tissue maintenance and/or regeneration should be very useful in identifying and functionally testing the mechanisms regulating stem cell activities. The planarian Schmidtea mediterranea is poised to fill this experimental gap. S. mediterranea displays robust regenerative properties driven by a stem cell population capable of producing the approximately 40 different cell types found in this organism, including the germ cells. Given that all known metazoans depend on stem cells for their survival, it is extremely likely that

  15. The Role of Stem Cells in the Etiology and Pathophysiology of Endometriosis.

    PubMed

    Hufnagel, Demetra; Li, Fei; Cosar, Emine; Krikun, Graciela; Taylor, Hugh S

    2015-09-01

    Human endometrium is a dynamic organ that normally undergoes repetitive cyclic regeneration. To enable this rapid regeneration, it is not surprising that the endometrium contains a reservoir of progenitor stem cells. However, this pool of cells that allows the growth of the endometrium also allows for unrestrained growth that can reach beyond the endometrium. In this review, we will address the role of stem cells in endometriosis. Recent characterization of stem cell populations within human endometrium has opened the possibility of understanding their physiologic as well as their pathologic roles. While stem cells are critical to the cyclic regeneration of a healthy endometrium, we have shown that both endometrium-derived and bone marrow-derived stem cells can migrate to ectopic sites and contribute to the development of endometriosis. Furthermore, endometriosis interferes with the normal stem cell trafficking to the uterus that is necessary for endometrial growth and repair. Altered stem cell mobility and engraftment characterize this disease. PMID:26375413

  16. The Role of Stem Cells in the Etiology and Pathophysiology of Endometriosis

    PubMed Central

    Hufnagel, Demetra; Li, Fei; Cosar, Emine; Krikun, Graciela; Taylor, Hugh S.

    2016-01-01

    Human endometrium is a dynamic organ that normally undergoes repetitive cyclic regeneration. To enable this rapid regeneration, it is not surprising that the endometrium contains a reservoir of progenitor stem cells. However, this pool of cells that allows the growth of the endometrium also allows for unrestrained growth that can reach beyond the endometrium. In this review, we will address the role of stem cells in endometriosis. Recent characterization of stem cell populations within human endometrium has opened the possibility of understanding their physiologic as well as their pathologic roles. While stem cells are critical to the cyclic regeneration of a healthy endometrium, we have shown that both endometrium-derived and bone marrow-derived stem cells can migrate to ectopic sites and contribute to the development of endometriosis. Furthermore, endometriosis interferes with the normal stem cell trafficking to the uterus that is necessary for endometrial growth and repair. Altered stem cell mobility and engraftment characterize this disease. PMID:26375413

  17. Modeling head and neck cancer stem cell-mediated tumorigenesis.

    PubMed

    Pearson, Alexander T; Jackson, Trachette L; Nör, Jacques E

    2016-09-01

    A large body of literature has emerged supporting the importance of cancer stem cells (CSCs) in the pathogenesis of head and neck cancers. CSCs are a subpopulation of cells within a tumor that share the properties of self-renewal and multipotency with stem cells from normal tissue. Their functional relevance to the pathobiology of cancer arises from the unique properties of tumorigenicity, chemotherapy resistance, and their ability to metastasize and invade distant tissues. Several molecular profiles have been used to discriminate a stem cell from a non-stem cell. CSCs can be grown for study and further enriched using a number of in vitro techniques. An evolving option for translational research is the use of mathematical and computational models to describe the role of CSCs in complex tumor environments. This review is focused discussing the evidence emerging from modeling approaches that have clarified the impact of CSCs to the biology of cancer. PMID:27151511

  18. Promise of cancer stem cell vaccine

    PubMed Central

    Zhou, Li; Lu, Lin; Wicha, Max S; Chang, Alfred E; Xia, Jian-chuan; Ren, Xiubao; Li, Qiao

    2015-01-01

    Dendritic cell (DC)-based vaccines designed to target cancer stem cells (CSC) can induce significant antitumor responses via conferring host anti-CSC immunity. Our recent studies have demonstrated that CSC-DC vaccine could inhibit metastasis of primary tumors and induce humoral immune responses against cancer stem cells. This approach highlights the promise of cancer stem cell vaccine in cancer immunotherapy. PMID:26337078

  19. 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

  20. Neural stem cells could serve as a therapeutic material for age-related neurodegenerative diseases.

    PubMed

    Suksuphew, Sarawut; Noisa, Parinya

    2015-03-26

    Progressively loss of neural and glial cells is the key event that leads to nervous system dysfunctions and diseases. Several neurodegenerative diseases, for instance Alzheimer's disease, Parkinson's disease, and Huntington's disease, are associated to aging and suggested to be a consequence of deficiency of neural stem cell pool in the affected brain regions. Endogenous neural stem cells exist throughout life and are found in specific niches of human brain. These neural stem cells are responsible for the regeneration of new neurons to restore, in the normal circumstance, the functions of the brain. Endogenous neural stem cells can be isolated, propagated, and, notably, differentiated to most cell types of the brain. On the other hand, other types of stem cells, such as mesenchymal stem cells, embryonic stem cells, and induced pluripotent stem cells can also serve as a source for neural stem cell production, that hold a great promise for regeneration of the brain. The replacement of neural stem cells, either endogenous or stem cell-derived neural stem cells, into impaired brain is highly expected as a possible therapeutic mean for neurodegenerative diseases. In this review, clinical features and current routinely treatments of age-related neurodegenerative diseases are documented. Noteworthy, we presented the promising evidence of neural stem cells and their derivatives in curing such diseases, together with the remaining challenges to achieve the best outcome for patients.

  1. Stem Cells in Teeth and Craniofacial Bones

    PubMed Central

    Zhao, H.; Chai, Y.

    2015-01-01

    Stem cells are remarkable, and stem cell–based tissue engineering is an emerging field of biomedical science aiming to restore damaged tissue or organs. In dentistry and reconstructive facial surgery, it is of great interest to restore lost teeth or craniofacial bone defects using stem cell–mediated therapy. In the craniofacial region, various stem cell populations have been identified with regeneration potential. In this review, we provide an overview of the current knowledge concerning the various types of tooth- and craniofacial bone–related stem cells and discuss their in vivo identities and regulating mechanisms. PMID:26350960

  2. Mammary stem cells have myoepithelial cell properties

    PubMed Central

    Prater, Michael D.; Petit, Valérie; Russell, I. Alasdair; Giraddi, Rajshekhar; Shehata, Mona; Menon, Suraj; Schulte, Reiner; Kalajzic, Ivo; Rath, Nicola; Olson, Michael F.; Metzger, Daniel; Faraldo, Marisa M.; Deugnier, Marie-Ange; Glukhova, Marina A.; Stingl, John

    2014-01-01

    Contractile myoepithelial cells dominate the basal layer of the mammary epithelium and are considered to be differentiated cells. However, we observe that up to 54% of single basal cells can form colonies when seeded into adherent culture in the presence of agents that disrupt acin-myosin interactions, and on average, 65% of the single-cell-derived basal colonies can repopulate a mammary gland when transplanted in vivo. This indicates that a high proportion of basal myoepithelial cells can give rise to a mammary repopulating unit (MRU). We demonstrate that myoepithelial cells, flow-sorted using 2 independent myoepithelial-specific reporter strategies, have MRU capacity. Using an inducible lineage tracing approach we follow the progeny of α-smooth muscle actin-expressing myoepithelial cells and show that they function as long-lived lineage-restricted stem cells in the virgin state and during pregnancy. PMID:25173976

  3. Therapeutic potential of amniotic fluid stem cells.

    PubMed

    Abdulrazzak, Hassan; De Coppi, Paolo; Guillot, Pascale V

    2013-03-01

    Human amniotic fluid cells have been used traditionally as a diagnostic tool for genetic anomalies. More recently it has been recognized that amniotic fluid contains populations of stem cells. Mesenchymal stem cells (AFMSC) were first to be described. These cells are able to differentiate towards mesodermal lineages. More recently cells with broader potential, defined as amniotic fluid stem cells (AFSC), were also isolated. They have intermediate characteristics between embryonic and adult stem cells and are able to differentiate into lineages representative of all three germ layers but unlike ES cells they do not form tumours in vivo. Furthermore, AFSC have been reverted to functional pluripotency in a transgene-free approach using an epigenetics modifier. These characteristics, together with absence of ethical issues concerning their employment, have made stem cells from amniotic fluid a promising candidate for cell therapy and tissue engineering.

  4. Stem Cell Therapy for Autism

    PubMed Central

    Ichim, Thomas E; Solano, Fabio; Glenn, Eduardo; Morales, Frank; Smith, Leonard; Zabrecky, George; Riordan, Neil H

    2007-01-01

    Autism spectrum disorders (ASD) are a group of neurodevelopmental conditions whose incidence is reaching epidemic proportions, afflicting approximately 1 in 166 children. Autistic disorder, or autism is the most common form of ASD. Although several neurophysiological alterations have been associated with autism, immune abnormalities and neural hypoperfusion appear to be broadly consistent. These appear to be causative since correlation of altered inflammatory responses, and hypoperfusion with symptology is reported. Mesenchymal stem cells (MSC) are in late phases of clinical development for treatment of graft versus host disease and Crohn's Disease, two conditions of immune dysregulation. Cord blood CD34+ cells are known to be potent angiogenic stimulators, having demonstrated positive effects in not only peripheral ischemia, but also in models of cerebral ischemia. Additionally, anecdotal clinical cases have reported responses in autistic children receiving cord blood CD34+ cells. We propose the combined use of MSC and cord blood CD34+cells may be useful in the treatment of autism. PMID:17597540

  5. Multiple Myeloma Cancer Stem Cells

    PubMed Central

    Huff, Carol Ann; Matsui, William

    2008-01-01

    Multiple myeloma is characterized by the clonal expansion of neoplastic plasma cells within the bone marrow, elevated serum immunoglobulin, and osteolytic bone disease. The disease is highly responsive to a wide variety of anticancer treatments including conventional cytotoxic chemotherapy, corticosteroids, radiation therapy, and a growing number of agents with novel mechanisms of action. However, few if any patients are cured with these modalities and relapse remains a critical issue. A better understanding of clonogenic multiple myleoma cells is essential to ultimately improving long-term outcomes, but the nature of the cells responsible for myeloma regrowth and disease relapse is unclear. We review evidence that functional heterogeneity exists in multiple myeloma and discuss potential strategies and clinical implications of the stem-cell model of cancer in this disease. PMID:18539970

  6. Stem cell therapy for autism.

    PubMed

    Ichim, Thomas E; Solano, Fabio; Glenn, Eduardo; Morales, Frank; Smith, Leonard; Zabrecky, George; Riordan, Neil H

    2007-06-27

    Autism spectrum disorders (ASD) are a group of neurodevelopmental conditions whose incidence is reaching epidemic proportions, afflicting approximately 1 in 166 children. Autistic disorder, or autism is the most common form of ASD. Although several neurophysiological alterations have been associated with autism, immune abnormalities and neural hypoperfusion appear to be broadly consistent. These appear to be causative since correlation of altered inflammatory responses, and hypoperfusion with symptology is reported. Mesenchymal stem cells (MSC) are in late phases of clinical development for treatment of graft versus host disease and Crohn's Disease, two conditions of immune dysregulation. Cord blood CD34+ cells are known to be potent angiogenic stimulators, having demonstrated positive effects in not only peripheral ischemia, but also in models of cerebral ischemia. Additionally, anecdotal clinical cases have reported responses in autistic children receiving cord blood CD34+ cells. We propose the combined use of MSC and cord blood CD34+cells may be useful in the treatment of autism.

  7. Injury induces direct lineage segregation of functionally distinct airway basal stem/progenitor cell subpopulations.

    PubMed

    Pardo-Saganta, Ana; Law, Brandon M; Tata, Purushothama Rao; Villoria, Jorge; Saez, Borja; Mou, Hongmei; Zhao, Rui; Rajagopal, Jayaraj

    2015-02-01

    Following injury, stem cells restore normal tissue architecture by producing the proper number and proportions of differentiated cells. Current models of airway epithelial regeneration propose that distinct cytokeratin 8-expressing progenitor cells, arising from p63(+) basal stem cells, subsequently differentiate into secretory and ciliated cell lineages. We now show that immediately following injury, discrete subpopulations of p63(+) airway basal stem/progenitor cells themselves express Notch pathway components associated with either secretory or ciliated cell fate commitment. One basal cell population displays intracellular Notch2 activation and directly generates secretory cells; the other expresses c-myb and directly yields ciliated cells. Furthermore, disrupting Notch ligand activity within the basal cell population at large disrupts the normal pattern of lineage segregation. These non-cell-autonomous effects demonstrate that effective airway epithelial regeneration requires intercellular communication within the broader basal stem/progenitor cell population. These findings have broad implications for understanding epithelial regeneration and stem cell heterogeneity.

  8. Establishment of a Mesenchymal Stem Cell Bank

    PubMed Central

    Cooper, Khushnuma; Viswanathan, Chandra

    2011-01-01

    Adult stem cells have generated great amount of interest amongst the scientific community for their potential therapeutic applications for unmet medical needs. We have demonstrated the plasticity of mesenchymal stem cells isolated from the umbilical cord matrix. Their immunological profile makes it even more interesting. We have demonstrated that the umbilical cord is an inexhaustible source of mesenchymal stem cells. Being a very rich source, instead of discarding this tissue, we worked on banking these cells for regenerative medicine application for future use. The present paper gives a detailed account of our experience in the establishment of a mesenchymal stem cell bank at our facility. PMID:21826152

  9. Mesenchymal Stem Cells in Cardiology.

    PubMed

    White, Ian A; Sanina, Cristina; Balkan, Wayne; Hare, Joshua M

    2016-01-01

    Cardiovascular disease (CVD) accounts for more deaths globally than any other single disease. There are on average 1.5 million episodes of myocardial infarction (heart attack) each year in the United States alone with roughly one-third resulting in death. There is therefore a major need for developing new and effective strategies to promote cardiac repair. Intramyocardial transplantation of mesenchymal stem cells (MSCs) has emerged as a leading contender in the pursuit of clinical intervention and therapy. MSCs are potent mediators of cardiac repair and are therefore an attractive tool in the development of preclinical and clinical trials. MSCs are capable of secreting a large array of soluble factors, which have had demonstrated effects on pathogenic cardiac remolding, fibrosis, immune activation, and cardiac stem cell proliferation within the damaged heart. MSCs are also capable of differentiation into cardiomyocytes, endothelial cells, and vascular smooth muscle cells, although the relative contribution of trilineage differentiation and paracrine effectors on cardiac repair remains the subject of active investigation. PMID:27236666

  10. Patenting human genes and stem cells.

    PubMed

    Martin-Rendon, Enca; Blake, Derek J

    2007-01-01

    Cell lines and genetically modified single cell organisms have been considered patentable subjects for the last two decades. However, despite the technical patentability of genes and stem cell lines, social and legal controversy concerning their 'ownership' has surrounded stem cell research in recent years. Some granted patents on stem cells with extremely broad claims are casting a shadow over the commercialization of these cells as therapeutics. However, in spite of those early patents, the number of patent applications related to stem cells is growing exponentially. Both embryonic and adult stem cells have the ability to differentiate into several cell lineages in an organism as a result of specific genetic programs that direct their commitment and cell fate. Genes that control the pluripotency of stem cells have been recently identified and the genetic manipulation of these cells is becoming more efficient with the advance of new technologies. This review summarizes some of the recent published patents on pluripotency genes, gene transfer into stem cells and genetic reprogramming and takes the hematopoietic and embryonic stem cell as model systems.

  11. Stem cells in the light of evolution

    PubMed Central

    Chakraborty, Chiranjib; Agoramoorthy, Govindasamy

    2012-01-01

    All organisms depend on stem cells for their survival. As a result, stem cells may be a prerequisite for the evolution of specific characteristics in organisms that include regeneration, multicellularity and coloniality. Stem cells have attracted the attention of biologists and medical scientists for a long time. These provide materials for regenerative medicine. We review in this paper, the link between modern stem cell research and early studies in ancient organisms. It also outlines details on stem cells in the light of evolution with an emphasis on their regeneration potential, coloniality and multicellularity. The information provided might be of use to molecular biologists, medical scientists and developmental biologists who are engaged in integrated research involving the stem cells. PMID:22825600

  12. Two-photon imaging of stem cells

    NASA Astrophysics Data System (ADS)

    Uchugonova, A.; Gorjup, E.; Riemann, I.; Sauer, D.; König, K.

    2008-02-01

    A variety of human and animal stem cells (rat and human adult pancreatic stem cells, salivary gland stem cells, dental pulpa stem cells) have been investigated by femtosecond laser 5D two-photon microscopy. Autofluorescence and second harmonic generation have been imaged with submicron spatial resolution, 270 ps temporal resolution, and 10 nm spectral resolution. In particular, NADH and flavoprotein fluorescence was detected in stem cells. Major emission peaks at 460nm and 530nm with typical mean fluorescence lifetimes of 1.8 ns and 2.0 ns, respectively, were measured using time-correlated single photon counting and spectral imaging. Differentiated stem cells produced the extracellular matrix protein collagen which was detected by SHG signals at 435 nm.

  13. Stem cell niche engineering through droplet microfluidics.

    PubMed

    Allazetta, Simone; Lutolf, Matthias P

    2015-12-01

    Stem cells reside in complex niches in which their behaviour is tightly regulated by various biochemical and biophysical signals. In order to unveil some of the crucial stem cell-niche interactions and expedite the implementation of stem cells in clinical and pharmaceutical applications, in vitro methodologies are being developed to reconstruct key features of stem cell niches. Recently, droplet-based microfluidics has emerged as a promising strategy to build stem cell niche models in a miniaturized and highly precise fashion. This review highlights current advances in using droplet microfluidics in stem cell biology. We also discuss recent efforts in which microgel technology has been interfaced with high-throughput analyses to engender screening paradigms with an unparalleled potential for basic and applied biological studies.

  14. Of Microenvironments and Mammary Stem Cells

    SciTech Connect

    LaBarge, Mark A; Petersen, Ole W; Bissell, Mina J

    2007-06-01

    In most adult tissues there reside pools of stem and progenitor cells inside specialized microenvironments referred to as niches. The niche protects the stem cells from inappropriate expansion and directs their critical functions. Thus guided, stem cells are able to maintain tissue homeostasis throughout the ebb and flow of metabolic and physical demands encountered over a lifetime. Indeed, a pool of stem cells maintains mammary gland structure throughout development, and responds to the physiological demands associated with pregnancy. This review discusses how stem cells were identified in both human and mouse mammary glands; each requiring different techniques that were determined by differing biological needs and ethical constraints. These studies together create a robust portrait of mammary gland biology and identify the location of the stem cell niche, elucidate a developmental hierarchy, and suggest how the niche might be manipulated for therapeutic benefit.

  15. Fueling Hope: Stem Cells in Social Media.

    PubMed

    Robillard, Julie M; Cabral, Emanuel; Hennessey, Craig; Kwon, Brian K; Illes, Judy

    2015-08-01

    Social media is broadening opportunities to engage in discussions about biomedical advances such as stem cell research. However, little is known about how information pertaining to stem cells is disseminated on platforms such as Twitter. To fill this gap, we conducted a content analysis of tweets containing (i) a stem cell keyword, and (ii) a keyword related to either spinal cord injury (SCI) or Parkinson disease (PD). We found that the discussion about stem cells and SCI or PD revolves around different aspects of the research process. We also found that the tone of most tweets about stem cells is either positive or neutral. The findings contribute new knowledge about Twitter as a connecting platform for many voices and as a key tool for the dissemination of information about stem cells and disorders of the central nervous system.

  16. Role of stem cells in tooth bioengineering

    PubMed Central

    Singh, Kamleshwar; Mishra, Niraj; Kumar, Lakshya; Agarwal, Kaushal Kishore; Agarwal, Bhaskar

    2012-01-01

    The creation of teeth in the laboratory depends upon the manipulation of stem cells and requires a synergy of all cellular and molecular events that finally lead to the formation of tooth-specific hard tissues, dentin, and enamel. This review focuses on the different sources of stem cells that have been used for making teeth in vitro. The search was performed from 1970 to 2012 and was limited to English language papers. The keywords searched on medline were ‘stem cells and dentistry,’ ‘stem cells and odontoblast,’ ‘stem cells and dentin,’ and ‘stem cells and ameloblasts.’ PMID:25756031

  17. [Stem cell therapy for neurodegenerative disorders].

    PubMed

    Meyer, Morten; Jensen, Pia; Rasmussen, Jens Zimmer

    2010-09-20

    Intrastriatal, foetal neural transplants can ameliorate symptoms in patients with Parkinson's and Huntington's disease, although not stop the primary cell-loss. Several issues must, however, be addressed before general or extended clinical use of cell therapy in neurodegenerative diseases can become a reality. Improvements include standardized and safe master cell-lines derived from human embryonic stem cells, induced pluripotent stem cells and neural stem cells. Cells from these sources are expected to become available for cell replacement therapies or therapeutic production of trophic, anti-inflammatory and restorative factors within a few years.

  18. Plasticity of epithelial stem cells in tissue regeneration

    PubMed Central

    Blanpain, Cédric; Fuchs, Elaine

    2015-01-01

    Tissues rely upon stem cells for homeostasis and repair. Recent studies show that the fate and multilineage potential of epithelial stem cells can change depending on whether a stem cell exists within its resident niche and responds to normal tissue homeostasis, whether it is mobilized to repair a wound, or whether it is taken from its niche and challenged to de novo tissue morphogenesis after transplantation. In this Review, we discuss how different populations of naturally lineage-restricted stem cells and committed progenitors can display remarkable plasticity and reversibility and reacquire long-term self-renewing capacities and multilineage differentiation potential during physiological and regenerative conditions. We also discuss the implications of cellular plasticity for regenerative medicine and for cancer. PMID:24926024

  19. Human stem cells and articular cartilage regeneration.

    PubMed

    Inui, Atsuyuki; Iwakura, Takashi; Reddi, A Hari

    2012-11-05

    The regeneration of articular cartilage damaged due to trauma and posttraumatic osteoarthritis is an unmet medical need. Current approaches to regeneration and tissue engineering of articular cartilage include the use of chondrocytes, stem cells, scaffolds and signals, including morphogens and growth factors. Stem cells, as a source of cells for articular cartilage regeneration, are a critical factor for articular cartilage regeneration. This is because articular cartilage tissue has a low cell turnover and does not heal spontaneously. Adult stem cells have been isolated from various tissues, such as bone marrow, adipose, synovial tissue, muscle and periosteum. Signals of the transforming growth factor beta superfamily play critical roles in chondrogenesis. However, adult stem cells derived from various tissues tend to differ in their chondrogenic potential. Pluripotent stem cells have unlimited proliferative capacity compared to adult stem cells. Chondrogenesis from embryonic stem (ES) cells has been studied for more than a decade. However, establishment of ES cells requires embryos and leads to ethical issues for clinical applications. Induced pluripotent stem (iPS) cells are generated by cellular reprogramming of adult cells by transcription factors. Although iPS cells have chondrogenic potential, optimization, generation and differentiation toward articular chondrocytes are currently under intense investigation.

  20. [Bioethical challenges of stem cell tourism].

    PubMed

    Ventura-Juncá, Patricio; Erices, Alejandro; Santos, Manuel J

    2013-08-01

    Stem cells have drawn extraordinary attention from scientists and the general public due to their potential to generate effective therapies for incurable diseases. At the same time, the production of embryonic stem cells involves a serious ethical issue concerning the destruction of human embryos. Although adult stem cells and induced pluripotential cells do not pose this ethical objection, there are other bioethical challenges common to all types of stem cells related particularly to the clinical use of stem cells. Their clinical use should be based on clinical trials, and in special situations, medical innovation, both of which have particular ethical dimensions. The media has raised unfounded expectations in patients and the public about the real clinical benefits of stem cells. At the same time, the number of unregulated clinics is increasing around the world, making direct offers through Internet of unproven stem cell therapies that attract desperate patients that have not found solutions in standard medicine. This is what is called stem cells tourism. This article reviews this situation, its consequences and the need for international cooperation to establish effective regulations to prevent the exploitation of patients and to endanger the prestige of legitimate stem cell research.

  1. Neural Stem Cells (NSCs) and Proteomics*

    PubMed Central

    Shoemaker, Lorelei D.; Kornblum, Harley I.

    2016-01-01

    Neural stem cells (NSCs) can self-renew and give rise to the major cell types of the CNS. Studies of NSCs include the investigation of primary, CNS-derived cells as well as animal and human embryonic stem cell (ESC)-derived and induced pluripotent stem cell (iPSC)-derived sources. NSCs provide a means with which to study normal neural development, neurodegeneration, and neurological disease and are clinically relevant sources for cellular repair to the damaged and diseased CNS. Proteomics studies of NSCs have the potential to delineate molecules and pathways critical for NSC biology and the means by which NSCs can participate in neural repair. In this review, we provide a background to NSC biology, including the means to obtain them and the caveats to these processes. We then focus on advances in the proteomic interrogation of NSCs. This includes the analysis of posttranslational modifications (PTMs); approaches to analyzing different proteomic compartments, such the secretome; as well as approaches to analyzing temporal differences in the proteome to elucidate mechanisms of differentiation. We also discuss some of the methods that will undoubtedly be useful in the investigation of NSCs but which have not yet been applied to the field. While many proteomics studies of NSCs have largely catalogued the proteome or posttranslational modifications of specific cellular states, without delving into specific functions, some have led to understandings of functional processes or identified markers that could not have been identified via other means. Many challenges remain in the field, including the precise identification and standardization of NSCs used for proteomic analyses, as well as how to translate fundamental proteomics studies to functional biology. The next level of investigation will require interdisciplinary approaches, combining the skills of those interested in the biochemistry of proteomics with those interested in modulating NSC function. PMID:26494823

  2. Neural Stem Cells (NSCs) and Proteomics.

    PubMed

    Shoemaker, Lorelei D; Kornblum, Harley I

    2016-02-01

    Neural stem cells (NSCs) can self-renew and give rise to the major cell types of the CNS. Studies of NSCs include the investigation of primary, CNS-derived cells as well as animal and human embryonic stem cell (ESC)-derived and induced pluripotent stem cell (iPSC)-derived sources. NSCs provide a means with which to study normal neural development, neurodegeneration, and neurological disease and are clinically relevant sources for cellular repair to the damaged and diseased CNS. Proteomics studies of NSCs have the potential to delineate molecules and pathways critical for NSC biology and the means by which NSCs can participate in neural repair. In this review, we provide a background to NSC biology, including the means to obtain them and the caveats to these processes. We then focus on advances in the proteomic interrogation of NSCs. This includes the analysis of posttranslational modifications (PTMs); approaches to analyzing different proteomic compartments, such the secretome; as well as approaches to analyzing temporal differences in the proteome to elucidate mechanisms of differentiation. We also discuss some of the methods that will undoubtedly be useful in the investigation of NSCs but which have not yet been applied to the field. While many proteomics studies of NSCs have largely catalogued the proteome or posttranslational modifications of specific cellular states, without delving into specific functions, some have led to understandings of functional processes or identified markers that could not have been identified via other means. Many challenges remain in the field, including the precise identification and standardization of NSCs used for proteomic analyses, as well as how to translate fundamental proteomics studies to functional biology. The next level of investigation will require interdisciplinary approaches, combining the skills of those interested in the biochemistry of proteomics with those interested in modulating NSC function. PMID:26494823

  3. The interfollicular epidermal stem cell saga: sensationalism versus reality check.

    PubMed

    Kaur, Pritinder; Potten, Christopher S

    2011-09-01

    Adult stem cells in rapidly renewing tissues have been classically defined as rare, relatively quiescent cells with the unique capacity to constantly self-renew and regenerate tissues during homeostasis. Although this view remains firmly embedded in the skin field, particularly in the area of hair follicle stem cell biology, it has been challenged by a number of notable publications in 2007. These papers leave an uncomfortable feeling with the reader if one believes that stem cells and transit amplifying cells are two polar opposites and 'never the twain shall meet.' Even if you do not subscribe to this extreme view, the implications appear to be far-reaching given that the majority of techniques devised for stem cell identification have used the fundamental tenet that the proliferating compartment is comprised of two distinct, mutually exclusive compartments, i.e. a minor proportion of long-lived quiescent stem cells with unlimited self-renewal and a large pool of rapidly cycling, short-lived transient amplifying cells with limited or no self-renewal capacity in normal steady-state conditions. However, these recent findings have resulted in papers that could be described as sensationalistic because they make little or no attempt to reconcile their observations with the large bulk of historical data with direct bearing on the interpretation of stem cell activity in normal steady-state conditions. Here, we offer some explanations that may help to integrate all of the data while presenting a case that both quiescent stem cells and cycling 'transit amplifying' cells contribute to epidermal replacement. PMID:21834906

  4. Stem cell reprogramming: A 3D boost

    NASA Astrophysics Data System (ADS)

    Abilez, Oscar J.; Wu, Joseph C.

    2016-03-01

    Biophysical factors in an optimized three-dimensional microenvironment enhance the reprogramming efficiency of human somatic cells into pluripotent stem cells when compared to traditional cell-culture substrates.

  5. Plant stem cells as innovation in cosmetics.

    PubMed

    Moruś, Martyna; Baran, Monika; Rost-Roszkowska, Magdalena; Skotnicka-Graca, Urszula

    2014-01-01

    The stem cells thanks to their ability of unlimited division number or transformation into different cell types creating organs, are responsible for regeneration processes. Depending on the organism in which the stem cells exists, they divide to the plant or animal ones. The later group includes the stem cells existing in both embryo's and adult human's organs. It includes, among others, epidermal stem cells, located in the hair follicle relieves and also in its basal layers, and responsible for permanent regeneration of the epidermis. Temporary science looks for method suitable for stimulation of the epidermis stem cells, amongst the other by delivery of e.g., growth factors for proliferation that decrease with the age. One of the methods is the use of the plant cell culture technology, including a number of methods that should ensure growth of plant cells, issues or organs in the environment with the microorganism-free medium. It uses abilities of the different plant cells to dedifferentiation into stem cells and coming back to the pluripotent status. The extracts obtained this way from the plant stem cells are currently used for production of both common or professional care cosmetics. This work describes exactly impact of the plant stem cell extract, coming from one type of the common apple tree (Uttwiler Spätlauber) to human skin as one of the first plant sorts, which are used in cosmetology and esthetic dermatology.

  6. Prospects of Stem Cells for Retinal Diseases.

    PubMed

    Ng, Tsz Kin; Lam, Dennis S C; Cheung, Herman S

    2013-01-01

    Retinal diseases, including glaucoma, retinitis pigmentosa, diabetic retinopathy, and age-related macular degeneration, are the leading causes of irreversible visual impairment and blindness in developed countries. Traditional and current treatment regimens are based on surgical or medical interventions to slow down the disease progression. However, the number of retinal cells would continue to diminish, and the diseases could not be completely cured. There is an emerging role of stem cells in retinal research. The stem cell therapy on retinal diseases is based on 2 theories: cell replacement therapy and neuroprotective effect. The former hypothesizes that new retinal cells could be regenerated from stem cells to substitute the damaged cells in the diseased retina, whereas the latter believes that the paracrine effects of stem cells modulate the microenvironments of the diseased retina so as to protect the retinal neurons. This article summarizes the choice of stem cells in retinal research. Moreover, the current progress of retinal research on stem cells and the clinical applications of stem cells on retinal diseases are reviewed. In addition, potential challenges and future prospects of retinal stem cell research are discussed.

  7. Burning Fat Fuels Leukemic Stem Cell Heterogeneity.

    PubMed

    Thomas, Daniel; Majeti, Ravindra

    2016-07-01

    Obese leukemia patients exhibit reduced survival after chemotherapy, suggesting an important role of adipose tissue in disease progression. In this issue of Cell Stem Cell, Ye et al. (2016) reveal metabolic heterogeneity in leukemic stem cell (LSC) subpopulations and show that chemotherapy-resistant CD36+ LSCs co-opt gonadal adipose tissue to support their metabolism and survival. PMID:27392217

  8. 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

  9. Ocular stem cells: a status update!

    PubMed

    Dhamodaran, Kamesh; Subramani, Murali; Ponnalagu, Murugeswari; Shetty, Reshma; Das, Debashish

    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.

  10. Hardwiring Stem Cell Communication through Tissue Structure.

    PubMed

    Xin, Tianchi; Greco, Valentina; Myung, Peggy

    2016-03-10

    Adult stem cells across diverse organs self-renew and differentiate to maintain tissue homeostasis. How stem cells receive input to preserve tissue structure and function largely relies on their communication with surrounding cellular and non-cellular elements. As such, how tissues are organized and patterned not only reflects organ function, but also inherently hardwires networks of communication between stem cells and their environment to direct tissue homeostasis and injury repair. This review highlights how different methods of stem cell communication reflect the unique organization and function of diverse tissues. PMID:26967287

  11. Hardwiring Stem Cell Communication through Tissue Structure.

    PubMed

    Xin, Tianchi; Greco, Valentina; Myung, Peggy

    2016-03-10

    Adult stem cells across diverse organs self-renew and differentiate to maintain tissue homeostasis. How stem cells receive input to preserve tissue structure and function largely relies on their communication with surrounding cellular and non-cellular elements. As such, how tissues are organized and patterned not only reflects organ function, but also inherently hardwires networks of communication between stem cells and their environment to direct tissue homeostasis and injury repair. This review highlights how different methods of stem cell communication reflect the unique organization and function of diverse tissues.

  12. Nanomaterials for Engineering Stem Cell Responses.

    PubMed

    Kerativitayanan, Punyavee; Carrow, James K; Gaharwar, Akhilesh K

    2015-08-01

    Recent progress in nanotechnology has stimulated the development of multifunctional biomaterials for tissue engineering applications. Synergistic interactions between nanomaterials and stem cell engineering offer numerous possibilities to address some of the daunting challenges in regenerative medicine, such as controlling trigger differentiation, immune reactions, limited supply of stem cells, and engineering complex tissue structures. Specifically, the interactions between stem cells and their microenvironment play key roles in controlling stem cell fate, which underlines therapeutic success. However, the interactions between nanomaterials and stem cells are not well understood, and the effects of the nanomaterials shape, surface morphology, and chemical functionality on cellular processes need critical evaluation. In this Review, focus is put on recent development in nanomaterial-stem cell interactions, with specific emphasis on their application in regenerative medicine. Further, the emerging technologies based on nanomaterials developed over the past decade for stem cell engineering are reviewed, as well as the potential applications of these nanomaterials in tissue regeneration, stem cell isolation, and drug/gene delivery. It is anticipated that the enhanced understanding of nanomaterial-stem cell interactions will facilitate improved biomaterial design for a range of biomedical and biotechnological applications.

  13. Wnt Signaling in Cancer Stem Cell Biology.

    PubMed

    de Sousa E Melo, Felipe; Vermeulen, Louis

    2016-06-27

    Aberrant regulation of Wnt signaling is a common theme seen across many tumor types. Decades of research have unraveled the epigenetic and genetic alterations that result in elevated Wnt pathway activity. More recently, it has become apparent that Wnt signaling levels identify stem-like tumor cells that are responsible for fueling tumor growth. As therapeutic targeting of these tumor stem cells is an intense area of investigation, a concise understanding on how Wnt activity relates to cancer stem cell traits is needed. This review attempts at summarizing the intricacies between Wnt signaling and cancer stem cell biology with a special emphasis on colorectal cancer.

  14. Genetic and epigenetic instability of stem cells.

    PubMed

    Rajamani, Karthyayani; Li, Yuan-Sheng; Hsieh, Dean-Kuo; Lin, Shinn-Zong; Harn, Horng-Jyh; Chiou, Tzyy-Wen

    2014-01-01

    Recently, research on stem cells has been receiving an increasing amount of attention, both for its advantages and disadvantages. Genetic and epigenetic instabilities among stem cells have been a recurring obstacle to progress in regenerative medicine using stem cells. Various reports have stated that these instabilities can transform stem cells when transferred in vivo and thus have the potential to develop tumors. Previous research has shown that various extrinsic and intrinsic factors can contribute to the stability of stem cells. The extrinsic factors include growth supplements, growth factors, oxygen tension, passage technique, and cryopreservation. Controlling these factors based on previous reports may assist researchers in developing strategies for the production and clinical application of "safe" stem cells. On the other hand, the intrinsic factors can be unpredictable and uncontrollable; therefore, to ensure the successful use of stem cells in regenerative medicine, it is imperative to develop and implement appropriate strategies and technique for culturing stem cells and to confirm the genetic and epigenetic safety of these stem cells before employing them in clinical trials.

  15. The Patentability of Stem Cells in Australia.

    PubMed

    Petering, Jenny; Cowin, Prue

    2015-07-01

    The potential therapeutic applications of stem cells are unlimited. However, the ongoing political and social debate surrounding the intellectual property and patenting considerations of stem cell research has led to the implementation of strict legislative regulations. In Australia the patent landscape surrounding stem cells has evolved considerably over the past 20 years. The Australian Patents Act 1990 includes a specific exclusion to the patentability of human beings and of biological processes for their generation. However, this exclusion has received no judicial consideration to date, and so its scope and potential impact on stem cell patents is unclear.

  16. Wnt Signaling in Cancer Stem Cell Biology

    PubMed Central

    de Sousa e Melo, Felipe; Vermeulen, Louis

    2016-01-01

    Aberrant regulation of Wnt signaling is a common theme seen across many tumor types. Decades of research have unraveled the epigenetic and genetic alterations that result in elevated Wnt pathway activity. More recently, it has become apparent that Wnt signaling levels identify stem-like tumor cells that are responsible for fueling tumor growth. As therapeutic targeting of these tumor stem cells is an intense area of investigation, a concise understanding on how Wnt activity relates to cancer stem cell traits is needed. This review attempts at summarizing the intricacies between Wnt signaling and cancer stem cell biology with a special emphasis on colorectal cancer. PMID:27355964

  17. Stomach development, stem cells and disease.

    PubMed

    Kim, Tae-Hee; Shivdasani, Ramesh A

    2016-02-15

    The stomach, an organ derived from foregut endoderm, secretes acid and enzymes and plays a key role in digestion. During development, mesenchymal-epithelial interactions drive stomach specification, patterning, differentiation and growth through selected signaling pathways and transcription factors. After birth, the gastric epithelium is maintained by the activity of stem cells. Developmental signals are aberrantly activated and stem cell functions are disrupted in gastric cancer and other disorders. Therefore, a better understanding of stomach development and stem cells can inform approaches to treating these conditions. This Review highlights the molecular mechanisms of stomach development and discusses recent findings regarding stomach stem cells and organoid cultures, and their roles in investigating disease mechanisms.

  18. 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

  19. [Stem cells - biology and therapeutic application].

    PubMed

    Sikora, Magdalena A; Olszewski, Waldemar L

    2004-04-01

    Enormous hope is connected with stem cells with regard to cell therapy, and this has become one of the most dynamically developing areas of science at the moment. A stem cell has unlimited potential for self-renewal. It appears that it can be a source of in vitro differentiated progeny cells capable of repairing damaged tissue. These review provides information about the biological properties of embryonic stem cells, i.e. ESs (embryonic stem cells), EGs (embryonic germ cells), and ECs (embryonic carcinoma cells). Possible human embryonic stem cell applications are described, with consideration of the desired cell line and the signals involved in their differentiation. The information about adult stem cells present - hemopoietic stem cells and the cells residing in selected tissues and organs: endothelium, pancreas, liver, epithelium, and gastrointestinal tract. Methods of their identification using the cell surfaces are also presented: the possibilities of in vitro transdifferentation, the phenomenon of in vivo plasticity, as well as morphological and genetic properties. Some topics of cell therapy and its clinical application in diabetics amplification are included. PMID:15114255

  20. Cancer stem cells: impact, heterogeneity, and uncertainty

    PubMed Central

    Magee, Jeffrey A.; Piskounova, Elena; Morrison, Sean J.

    2015-01-01

    The differentiation of tumorigenic cancer stem cells into non-tumorigenic cancer cells confers heterogeneity to some cancers beyond that explained by clonal evolution or environmental differences. In such cancers, functional differences between tumorigenic and non-tumorigenic cells influence response to therapy and prognosis. However, it remains uncertain whether the model applies to many, or few, cancers due to questions about the robustness of cancer stem cell markers and the extent to which existing assays underestimate the frequency of tumorigenic cells. In cancers with rapid genetic change, reversible changes in cell states, or biological variability among patients the stem cell model may not be readily testable. PMID:22439924

  1. Isolation of Mouse Hair Follicle Bulge Stem Cells and Their Functional Analysis in a Reconstitution Assay.

    PubMed

    Zheng, Ying; Hsieh, Jen-Chih; Escandon, Julia; Cotsarelis, George

    2016-01-01

    The hair follicle (HF) is a dynamic structure readily accessible within the skin, and contains various pools of stem cells that have a broad regenerative potential during normal homeostasis and in response to injury. Recent discoveries demonstrating the multipotent capabilities of hair follicle stem cells and the easy access to skin tissue make the HF an attractive source for isolating stem cells and their subsequent application in tissue engineering and regenerative medicine. Here, we describe the isolation and purification of hair follicle bulge stem cells from mouse skin, and hair reconstitution assays that allows the functional analysis of multipotent stem cells. PMID:27431247

  2. Single-cell sequencing in stem cell biology.

    PubMed

    Wen, Lu; Tang, Fuchou

    2016-04-15

    Cell-to-cell variation and heterogeneity are fundamental and intrinsic characteristics of stem cell populations, but these differences are masked when bulk cells are used for omic analysis. Single-cell sequencing technologies serve as powerful tools to dissect cellular heterogeneity comprehensively and to identify distinct phenotypic cell types, even within a 'homogeneous' stem cell population. These technologies, including single-cell genome, epigenome, and transcriptome sequencing technologies, have been developing rapidly in recent years. The application of these methods to different types of stem cells, including pluripotent stem cells and tissue-specific stem cells, has led to exciting new findings in the stem cell field. In this review, we discuss the recent progress as well as future perspectives in the methodologies and applications of single-cell omic sequencing technologies.

  3. Cancer stem cells: progress and challenges in lung cancer.

    PubMed

    Templeton, Amanda K; Miyamoto, Shinya; Babu, Anish; Munshi, Anupama; Ramesh, Rajagopal

    2014-01-01

    The identification of a subpopulation of tumor cells with stem cell-like characteristics first in hematological malignancies and later in solid tumors has emerged into a novel field of cancer research. It has been proposed that this aberrant population of cells now called "cancer stem cells" (CSCs) drives tumor initiation, progression, metastasis, recurrence, and drug resistance. CSCs have been shown to have the capacity of self-renewal and multipotency. Adopting strategies from the field of stem cell research has aided in identification, localization, and targeting of CSCs in many tumors. Despite the huge progress in other solid tumors such as brain, breast, and colon cancers no substantial advancements have been made in lung cancer. This is most likely due to the current rudimentary understanding of lung stem cell hierarchy and heterogeneous nature of lung disease. In this review, we will discuss the most recent findings related to identification of normal lung stem cells and CSCs, pathways involved in regulating the development of CSCs, and the importance of the stem cell niche in development and maintenance of CSCs. Additionally, we will examine the development and feasibility of novel CSC-targeted therapeutic strategies aimed at eradicating lung CSCs. PMID:27358855

  4. Current Biosafety Considerations in Stem Cell Therapy.

    PubMed

    Mousavinejad, Masoumeh; Andrews, Peter W; Shoraki, Elham Kargar

    2016-01-01

    Stem cells can be valuable model systems for drug discovery and modelling human diseases as well as to investigate cellular interactions and molecular events in the early stages of development. Controlling the differentiation of stem cells into specific germ layers provides a potential source of highly specialized cells for therapeutic applications. In recent years, finding individual properties of stem cells such as their ultimate self-renewal capacity and the generation of particular cell lines by differentiation under specific culture conditions underpins the development of regenerative therapies. These futures make stem cells a leading candidate to treat a wide range of diseases. Nevertheless, as with all novel treatments, safety issues are one of the barriers that should be overcome to guarantee the quality of a patient's life after stem cell therapy. Many studies have pointed to a large gap in our knowledge about the therapeutic applications of these cells. This gap clearly shows the importance of biosafety concerns for the current status of cell-based therapies, even more than their therapeutic efficacy. Currently, scientists report that tumorigenicity and immunogenicity are the two most important associated cell-based therapy risks. In principle, intrinsic factors such as cell characteristics and extrinsic elements introduced by manufacturing of stem cells can result in tumor formation and immunological reactions after stem cell transplantation. Therapeutic research shows there are many biological questions regarding safety issues of stem cell clinical applications. Stem cell therapy is a rapidly advancing field that needs to focus more on finding a comprehensive technology for assessing risk. A variety of risk factors (from intrinsic to extrinsic) should be considered for safe clinical stem cell therapies. PMID:27540533

  5. Current Biosafety Considerations in Stem Cell Therapy

    PubMed Central

    Mousavinejad, Masoumeh; Andrews, Peter W.; Shoraki, Elham Kargar

    2016-01-01

    Stem cells can be valuable model systems for drug discovery and modelling human diseases as well as to investigate cellular interactions and molecular events in the early stages of development. Controlling the differentiation of stem cells into specific germ layers provides a potential source of highly specialized cells for therapeutic applications. In recent years, finding individual properties of stem cells such as their ultimate self-renewal capacity and the generation of particular cell lines by differentiation under specific culture conditions underpins the development of regenerative therapies. These futures make stem cells a leading candidate to treat a wide range of diseases. Nevertheless, as with all novel treatments, safety issues are one of the barriers that should be overcome to guarantee the quality of a patient’s life after stem cell therapy. Many studies have pointed to a large gap in our knowledge about the therapeutic applications of these cells. This gap clearly shows the importance of biosafety concerns for the current status of cell-based therapies, even more than their therapeutic efficacy. Currently, scientists report that tumorigenicity and immunogenicity are the two most important associated cell-based therapy risks. In principle, intrinsic factors such as cell characteristics and extrinsic elements introduced by manufacturing of stem cells can result in tumor formation and immunological reactions after stem cell transplantation. Therapeutic research shows there are many biological questions regarding safety issues of stem cell clinical applications. Stem cell therapy is a rapidly advancing field that needs to focus more on finding a comprehensive technology for assessing risk. A variety of risk factors (from intrinsic to extrinsic) should be considered for safe clinical stem cell therapies. PMID:27540533

  6. Strategies to improve homing of mesenchymal stem cells for greater efficacy in stem cell therapy.

    PubMed

    Naderi-Meshkin, Hojjat; Bahrami, Ahmad Reza; Bidkhori, Hamid Reza; Mirahmadi, Mahdi; Ahmadiankia, Naghmeh

    2015-01-01

    Stem/progenitor cell-based therapeutic approach in clinical practice has been an elusive dream in medical sciences, and improvement of stem cell homing is one of major challenges in cell therapy programs. Stem/progenitor cells have a homing response to injured tissues/organs, mediated by interactions of chemokine receptors expressed on the cells and chemokines secreted by the injured tissue. For improvement of directed homing of the cells, many techniques have been developed either to engineer stem/progenitor cells with higher amount of chemokine receptors (stem cell-based strategies) or to modulate the target tissues to release higher level of the corresponding chemokines (target tissue-based strategies). This review discusses both of these strategies involved in the improvement of stem cell homing focusing on mesenchymal stem cells as most frequent studied model in cellular therapies.

  7. Stem cells in bone tissue engineering.

    PubMed

    Seong, Jeong Min; Kim, Byung-Chul; Park, Jae-Hong; Kwon, Il Keun; Mantalaris, Anathathios; Hwang, Yu-Shik

    2010-12-01

    Bone tissue engineering has been one of the most promising areas of research, providing a potential clinical application to cure bone defects. Recently, various stem cells including embryonic stem cells (ESCs), bone marrow-derived mesenchymal stem cells (BM-MSCs), umbilical cord blood-derived mesenchymal stem cells (UCB-MSCs), adipose tissue-derived stem cells (ADSCs), muscle-derived stem cells (MDSCs) and dental pulp stem cells (DPSCs) have received extensive attention in the field of bone tissue engineering due to their distinct biological capability to differentiate into osteogenic lineages. The application of these stem cells to bone tissue engineering requires inducing in vitro differentiation of these cells into bone forming cells, osteoblasts. For this purpose, efficient in vitro differentiation towards osteogenic lineage requires the development of well-defined and proficient protocols. This would reduce the likelihood of spontaneous differentiation into divergent lineages and increase the available cell source for application to bone tissue engineering therapies. This review provides a critical examination of the various experimental strategies that could be used to direct the differentiation of ESC, BM-MSC, UCB-MSC, ADSC, MDSC and DPSC towards osteogenic lineages and their potential applications in tissue engineering, particularly in the regeneration of bone.

  8. Generation of new islets from stem cells.

    PubMed

    Roche, Enrique; Soria, Bernat

    2004-01-01

    Spain ranks number one in organ donors (35 per million per yr). Although the prevalence of diabetes is low (100,000 type 1 diabetic patients and 2 million type 2 diabetic patients), the expected number of patients receiving islet transplants should be estimated at 200 per year. Islet replacement represents a promising cure for diabetes and has been successfully applied in a limited number of type 1 diabetic patients, resulting in insulin independence for periods longer than 3 yr. However, it has been difficult to obtain sufficient numbers of islets from cadaveric donors. Interesting alternatives include acquiring renewable sources of cells using either embryonic or adult stem cells to overcome the islet scarcity problem. Stem cells are capable of extensive proliferation rates and are capable of differentiating into other cell types of the body. In particular, totipotent stem cells are capable of differentiating into all cell types in the body, whereas pluripotent stem cells are limited to the development of a certain number of differentiated cell types. Insulin-producing cells have been obtained from both embryonic and adult stem cells using several approaches. In animal models of diabetes, the therapeutic application of bioengineered insulin-secreting cells derived from stem cells has delivered promising results. This review will summarize the different approaches that have been used to obtain insulin-producing cells from embryonic and adult stem cells and highlights the key points that will allow in vitro differentiation and subsequent transplantation in the future. PMID:15289648

  9. Adult stem-like cells in kidney

    PubMed Central

    Hishikawa, Keiichi; Takase, Osamu; Yoshikawa, Masahiro; Tsujimura, Taro; Nangaku, Masaomi; Takato, Tsuyoshi

    2015-01-01

    Human pluripotent cells are promising for treatment for kidney diseases, but the protocols for derivation of kidney cell types are still controversial. Kidney tissue regeneration is well confirmed in several lower vertebrates such as fish, and the repair of nephrons after tubular damages is commonly observed after renal injury. Even in adult mammal kidney, renal progenitor cell or system is reportedly presents suggesting that adult stem-like cells in kidney can be practical clinical targets for kidney diseases. However, it is still unclear if kidney stem cells or stem-like cells exist or not. In general, stemness is defined by several factors such as self-renewal capacity, multi-lineage potency and characteristic gene expression profiles. The definite use of stemness may be obstacle to understand kidney regeneration, and here we describe the recent broad findings of kidney regeneration and the cells that contribute regeneration. PMID:25815133

  10. Nonclinical safety strategies for stem cell therapies

    SciTech Connect

    Sharpe, Michaela E.; Morton, Daniel; Rossi, Annamaria

    2012-08-01

    Recent breakthroughs in stem cell biology, especially the development of the induced pluripotent stem cell techniques, have generated tremendous enthusiasm and efforts to explore the therapeutic potential of stem cells in regenerative medicine. Stem cell therapies are being considered for the treatment of degenerative diseases, inflammatory conditions, cancer and repair of damaged tissue. The safety of a stem cell therapy depends on many factors including the type of cell therapy, the differentiation status and proliferation capacity of the cells, the route of administration, the intended clinical location, long term survival of the product and/or engraftment, the need for repeated administration, the disease to be treated and the age of the population. Understanding the product profile of the intended therapy is crucial to the development of the nonclinical safety study design.

  11. Adult stem-like cells in kidney.

    PubMed

    Hishikawa, Keiichi; Takase, Osamu; Yoshikawa, Masahiro; Tsujimura, Taro; Nangaku, Masaomi; Takato, Tsuyoshi

    2015-03-26

    Human pluripotent cells are promising for treatment for kidney diseases, but the protocols for derivation of kidney cell types are still controversial. Kidney tissue regeneration is well confirmed in several lower vertebrates such as fish, and the repair of nephrons after tubular damages is commonly observed after renal injury. Even in adult mammal kidney, renal progenitor cell or system is reportedly presents suggesting that adult stem-like cells in kidney can be practical clinical targets for kidney diseases. However, it is still unclear if kidney stem cells or stem-like cells exist or not. In general, stemness is defined by several factors such as self-renewal capacity, multi-lineage potency and characteristic gene expression profiles. The definite use of stemness may be obstacle to understand kidney regeneration, and here we describe the recent broad findings of kidney regeneration and the cells that contribute regeneration. PMID:25815133

  12. Mesenchymal Stem/Stromal Cells Derived from Induced Pluripotent Stem Cells Support CD34(pos) Hematopoietic Stem Cell Propagation and Suppress Inflammatory Reaction.

    PubMed

    Moslem, Mohsen; Eberle, Irina; Weber, Iuliia; Henschler, Reinhard; Cantz, Tobias

    2015-01-01

    Mesenchymal stem/stromal cells (MSCs) represent a promising cell source for research and therapeutic applications, but their restricted ex vivo propagation capabilities limit putative applications. Substantial self-renewing of stem cells can be achieved by reprogramming cells into induced pluripotent stem cells (iPSCs) that can be easily expanded as undifferentiated cells even in mass culture. Here, we investigated a differentiation protocol enabling the generation and selection of human iPSC-derived MSCs exhibiting relevant surface marker expression profiles (CD105 and CD73) and functional characteristics. We generated such iPSC-MSCs from fibroblasts and bone marrow MSCs utilizing two different reprogramming constructs. All such iPSC-MSCs exhibited the characteristics of normal bone marrow-derived (BM) MSCs. In direct comparison to BM-MSCs our iPSC-MSCs exhibited a similar surface marker expression profile but shorter doubling times without reaching senescence within 20 passages. Considering functional capabilities, iPSC-MSCs provided supportive feeder layer for CD34(+) hematopoietic stem cells' self-renewal and colony forming capacities. Furthermore, iPSC-MSCs gained immunomodulatory function to suppress CD4(+) cell proliferation, reduce proinflammatory cytokines in mixed lymphocyte reaction, and increase regulatory CD4(+)/CD69(+)/CD25(+) T-lymphocyte population. In conclusion, we generated fully functional MSCs from various iPSC lines irrespective of their starting cell source or reprogramming factor composition and we suggest that such iPSC-MSCs allow repetitive cell applications for advanced therapeutic approaches. PMID:26185499

  13. Neurogenic differentiation of amniotic fluid stem cells.

    PubMed

    Rosner, M; Mikula, M; Preitschopf, A; Feichtinger, M; Schipany, K; Hengstschläger, M

    2012-05-01

    In 2003, human amniotic fluid has been shown to contain stem cells expressing Oct-4, a marker for pluripotency. This finding initiated a rapidly growing and very promising new stem cell research field. Since then, amniotic fluid stem (AFS) cells have been demonstrated to harbour the potential to differentiate into any of the three germ layers and to form three-dimensional aggregates, so-called embryoid bodies, known as the principal step in the differentiation of pluripotent stem cells. Marker selection and minimal dilution approaches allow the establishment of monoclonal AFS cell lineages with high proliferation potential. AFS cells have a lower risk for tumour development and do not raise the ethical issues of embryonic stem cells. Compared to induced pluripotent stem cells, AFS cells do not need exogenic treatment to induce pluripotency, are chromosomal stable and do not harbour the epigenetic memory and accumulated somatic mutations of specific differentiated source cells. Compared to adult stem cells, AFS can be grown in larger quantities and show higher differentiation potential. Accordingly, in the recent past, AFS became increasingly accepted as an optimal tool for basic research and probably also for specific cell-based therapies. Here, we review the current knowledge on the neurogenic differentiation potential of AFS cells.

  14. Prostate cancer stem cell biology

    PubMed Central

    Yu, Chunyan; Yao, Zhi; Jiang, Yuan; Keller, Evan. T.

    2012-01-01

    The cancer stem cell (CSC) model provides insights into pathophysiology of cancers and their therapeutic response. The CSC model has been both controversial, yet provides a foundation to explore cancer biology. In this review, we provide an overview of CSC concepts, biology and potential therapeutic avenues. We then focus on prostate CSC including (1) their purported origin as either basal-derived or luminal-derived cells; (2) markers used for prostate CSC identification; (3) alterations of signaling pathways in prostate CSCs (4) involvement of prostate CSCs in metastasis of PCa and (5) microRNA-mediated regulation of prostate CSCs. Although definitive evidence for the identification and characterization of prostate CSCs still remains unclear, future directions pursuing therapeutic targets of CSCs may provide novel insights for the treatment of PCa. PMID:22402315

  15. PrPC from stem cells to cancer

    PubMed Central

    Martin-Lannerée, Séverine; Hirsch, Théo Z.; Hernandez-Rapp, Julia; Halliez, Sophie; Vilotte, Jean-Luc; Launay, Jean-Marie; Mouillet-Richard, Sophie

    2014-01-01

    The cellular prion protein PrPC was initially discovered as the normal counterpart of the pathological scrapie prion protein PrPSc, the main component of the infectious agent of Transmissible Spongiform Encephalopathies. While clues as to the physiological function of this ubiquitous protein were greatly anticipated from the development of knockout animals, PrP-null mice turned out to be viable and to develop without major phenotypic abnormalities. Notwithstanding, the discovery that hematopoietic stem cells from PrP-null mice have impaired long-term repopulating potential has set the stage for investigating into the role of PrPC in stem cell biology. A wealth of data have now exemplified that PrPC is expressed in distinct types of stem cells and regulates their self-renewal as well as their differentiation potential. A role for PrPC in the fate restriction of embryonic stem cells has further been proposed. Paralleling these observations, an overexpression of PrPC has been documented in various types of tumors. In line with the contribution of PrPC to stemness and to the proliferation of cancer cells, PrPC was recently found to be enriched in subpopulations of tumor-initiating cells. In the present review, we summarize the current knowledge of the role played by PrPC in stem cell biology and discuss how the subversion of its function may contribute to cancer progression. PMID:25364760

  16. Cancer stem cells: progress and challenges in lung cancer

    PubMed Central

    Templeton, Amanda K.; Miyamoto, Shinya; Babu, Anish; Munshi, Anupama

    2014-01-01

    The identification of a subpopulation of tumor cells with stem cell-like characteristics first in hematological malignancies and later in solid tumors has emerged into a novel field of cancer research. It has been proposed that this aberrant population of cells now called “cancer stem cells” (CSCs) drives tumor initiation, progression, metastasis, recurrence, and drug resistance. CSCs have been shown to have the capacity of self-renewal and multipotency. Adopting strategies from the field of stem cell research has aided in identification, localization, and targeting of CSCs in many tumors. Despite the huge progress in other solid tumors such as brain, breast, and colon cancers no substantial advancements have been made in lung cancer. This is most likely due to the current rudimentary understanding of lung stem cell hierarchy and heterogeneous nature of lung disease. In this review, we will discuss the most recent findings related to identification of normal lung stem cells and CSCs, pathways involved in regulating the development of CSCs, and the importance of the stem cell niche in development and maintenance of CSCs. Additionally, we will examine the development and feasibility of novel CSC-targeted therapeutic strategies aimed at eradicating lung CSCs. PMID:27358855

  17. Stem cells and bone diseases: new tools, new perspective.

    PubMed

    Riminucci, Mara; Remoli, Cristina; Robey, Pamela G; Bianco, Paolo

    2015-01-01

    Postnatal skeletal stem cells are a unique class of progenitors with biological properties that extend well beyond the limits of stemness as commonly defined. Skeletal stem cells sustain skeletal tissue homeostasis, organize and maintain the complex architectural structure of the bone marrow microenvironment and provide a niche for hematopoietic progenitor cells. The identification of stem cells in the human post-natal skeleton has profoundly changed our approach to the physiology and pathology of this system. Skeletal diseases have been long interpreted essentially in terms of defective function of differentiated cells and/or abnormal turnover of the matrix that they produce. The notion of a skeletal stem cell has brought forth multiple, novel concepts in skeletal biology that provide potential alternative concepts. At the same time, the recognition of the complex functions played by skeletal progenitors, such as the structural and functional organization of the bone marrow, has provided an innovative, unifying perspective for understanding bone and bone marrow changes simultaneously occurring in many disorders. Finally, the possibility to isolate and highly enrich for skeletal progenitors, enables us to reproduce perfectly normal or pathological organ miniatures. These, in turn, provide suitable models to investigate and manipulate the pathogenetic mechanisms of many genetic and non-genetic skeletal diseases. This article is part of a Special Issue entitled Stem cells and Bone.

  18. Stem cell depletion in Hutchinson-Gilford progeria syndrome.

    PubMed

    Rosengardten, Ylva; McKenna, Tomás; Grochová, Diana; Eriksson, Maria

    2011-12-01

    Hutchinson-Gilford progeria syndrome (HGPS or progeria) is a very rare genetic disorder with clinical features suggestive of premature aging. Here, we show that induced expression of the most common HGPS mutation (LMNA c.1824C>T, p.G608G) results in a decreased epidermal population of adult stem cells and impaired wound healing in mice. Isolation and growth of primary keratinocytes from these mice demonstrated a reduced proliferative potential and ability to form colonies. Downregulation of the epidermal stem cell maintenance protein p63 with accompanying activation of DNA repair and premature senescence was the probable cause of this loss of adult stem cells. Additionally, upregulation of multiple genes in major inflammatory pathways indicated an activated inflammatory response. This response has also been associated with normal aging, emphasizing the importance of studying progeria to increase the understanding of the normal aging process.

  19. Glial cell derived neurotrophic factor induces spermatogonial stem cell marker genes in chicken mesenchymal stem cells.

    PubMed

    Boozarpour, Sohrab; Matin, Maryam M; Momeni-Moghaddam, Madjid; Dehghani, Hesam; Mahdavi-Shahri, Naser; Sisakhtnezhad, Sajjad; Heirani-Tabasi, Asieh; Irfan-Maqsood, Muhammad; Bahrami, Ahmad Reza

    2016-06-01

    Mesenchymal stem cells (MSCs) are known with the potential of multi-lineage differentiation. Advances in differentiation technology have also resulted in the conversion of MSCs to other kinds of stem cells. MSCs are considered as a suitable source of cells for biotechnology purposes because they are abundant, easily accessible and well characterized cells. Nowadays small molecules are introduced as novel and efficient factors to differentiate stem cells. In this work, we examined the potential of glial cell derived neurotrophic factor (GDNF) for differentiating chicken MSCs toward spermatogonial stem cells. MSCs were isolated and characterized from chicken and cultured under treatment with all-trans retinoic acid (RA) or glial cell derived neurotrophic factor. Expression analysis of specific genes after 7days of RA treatment, as examined by RT-PCR, proved positive for some germ cell markers such as CVH, STRA8, PLZF and some genes involved in spermatogonial stem cell maintenance like BCL6b and c-KIT. On the other hand, GDNF could additionally induce expression of POU5F1, and NANOG as well as other genes which were induced after RA treatment. These data illustrated that GDNF is relatively more effective in diverting chicken MSCs towards Spermatogonial stem cell -like cells in chickens and suggests GDNF as a new agent to obtain transgenic poultry, nevertheless, exploitability of these cells should be verified by more experiments. PMID:27026484

  20. Glial cell derived neurotrophic factor induces spermatogonial stem cell marker genes in chicken mesenchymal stem cells.

    PubMed

    Boozarpour, Sohrab; Matin, Maryam M; Momeni-Moghaddam, Madjid; Dehghani, Hesam; Mahdavi-Shahri, Naser; Sisakhtnezhad, Sajjad; Heirani-Tabasi, Asieh; Irfan-Maqsood, Muhammad; Bahrami, Ahmad Reza

    2016-06-01

    Mesenchymal stem cells (MSCs) are known with the potential of multi-lineage differentiation. Advances in differentiation technology have also resulted in the conversion of MSCs to other kinds of stem cells. MSCs are considered as a suitable source of cells for biotechnology purposes because they are abundant, easily accessible and well characterized cells. Nowadays small molecules are introduced as novel and efficient factors to differentiate stem cells. In this work, we examined the potential of glial cell derived neurotrophic factor (GDNF) for differentiating chicken MSCs toward spermatogonial stem cells. MSCs were isolated and characterized from chicken and cultured under treatment with all-trans retinoic acid (RA) or glial cell derived neurotrophic factor. Expression analysis of specific genes after 7days of RA treatment, as examined by RT-PCR, proved positive for some germ cell markers such as CVH, STRA8, PLZF and some genes involved in spermatogonial stem cell maintenance like BCL6b and c-KIT. On the other hand, GDNF could additionally induce expression of POU5F1, and NANOG as well as other genes which were induced after RA treatment. These data illustrated that GDNF is relatively more effective in diverting chicken MSCs towards Spermatogonial stem cell -like cells in chickens and suggests GDNF as a new agent to obtain transgenic poultry, nevertheless, exploitability of these cells should be verified by more experiments.

  1. ALPHA-FETOPROTEIN (AFP), STEM CELLS, AND CANCER: HOW STUDY OF THE PRODUCTION OF AFP DURING CHEMICAL HEPATOCARCINOGENESIS LED TO REAFFIRMATION OF THE STEM CELL THEORY OF CANCER

    PubMed Central

    Sell, Stewart

    2008-01-01

    Identification of the cells in the liver that produce alpha-fetoprotein (AFP) during development, in response to liver injury, and during the early stages of chemical hepatocarcinogenesis led to the conclusion that maturation arrest of liver-determined tissue stem cells was the cellular process that gives rise to hepatocellular carcinomas (HCC). When the cellular changes in these processes were compared that of the formation of teratocarcinomas, the hypothesis arose that all cancers arise from maturation arrest of tissue determined stem cells. This was essentially a reinterpretation of the embryonal rest theory of cancer whereby tissue stem cells take the role of embryonal rests. A corollary of the stem cell theory of the origin of cancer is that cancers contain the same functional cell populations as do normal tissues: stem cells, transit-amplifying cells, and mature cells. Cancer stem cells retain the essential feature of normal stem cells: the ability to self-renew. Growth of cancers is due to continued proliferation of cancer transit-amplifying cells that do not differentiate to mature cells (maturation arrest). On the other hand, cancer stem cells generally divide very rarely and contribute little to tumor growth. However, the presence of cancer stem cells in tumors is believed to be responsible for the properties of immortalization, transplantability and resistance to therapy characteristic of cancers. Current therapies for cancer (chemotherapy, radiotherapy, anti-angiogenesis and differentiation therapy) are directed against the cancer transit amplifying cells. When these therapies are discontinued, the cancer re-forms from the cancer stem cells. Therapy directed toward interruption of the cell-signaling pathways that maintain cancer stem cells could lead to new modalities to the prevention of re-growth of the cancer. PMID:18612221

  2. Enhancing spontaneous stem cell healing (Review)

    PubMed Central

    MAGUIRE, GREG; FRIEDMAN, PETER

    2014-01-01

    Adult stem cells are distributed throughout the human body and are responsible to a great extent for the body’s ability to maintain and heal itself. Accumulating data since the 1990s regarding stem cells have demonstrated that the beneficial effects of stem cells are not restricted to their ability to differentiate and are more likely due to their ability to release a multitude of molecules. Recent studies indicated that ≤80% of the therapeutic benefit of adult stem cells is manifested by the stem cell released molecules (SRM) rather than the differentiation of the stem cells into mature tissue. Stem cells may release potent combinations of factors that modulate the molecular composition of the cellular milieu to evoke a multitude of responses from neighboring cells. A multitude of pathways are involved in cellular and tissue function and, when the body is in a state of disease or trauma, a multitude of pathways are involved in the underlying mechanisms of that disease or trauma. Therefore, stem cells represent a natural systems-based biological factory for the production and release of a multitude of molecules that interact with the system of biomolecular circuits underlying disease or tissue damage. Currently, efforts are aimed at defining, stimulating, enhancing and harnessing SRM mechanisms, in order to develop systems-based methods for tissue regeneration, develop drugs/biologics or other therapeutics and enhance the release of SRM into the body for natural healing through proper dietary, exercise and other lifestyle strategies. PMID:24649089

  3. Stem cells of the skin epithelium

    PubMed Central

    Alonso, Laura; Fuchs, Elaine

    2003-01-01

    Tissue stem cells form the cellular base for organ homeostasis and repair. Stem cells have the unusual ability to renew themselves over the lifetime of the organ while producing daughter cells that differentiate into one or multiple lineages. Difficult to identify and characterize in any tissue, these cells are nonetheless hotly pursued because they hold the potential promise of therapeutic reprogramming to grow human tissue in vitro, for the treatment of human disease. The mammalian skin epithelium exhibits remarkable turnover, punctuated by periods of even more rapid production after injury due to burn or wounding. The stem cells responsible for supplying this tissue with cellular substrate are not yet easily distinguishable from neighboring cells. However, in recent years a significant body of work has begun to characterize the skin epithelial stem cells, both in tissue culture and in mouse and human skin. Some epithelial cells cultured from skin exhibit prodigious proliferative potential; in fact, for >20 years now, cultured human skin has been used as a source of new skin to engraft onto damaged areas of burn patients, representing one of the first therapeutic uses of stem cells. Cell fate choices, including both self-renewal and differentiation, are crucial biological features of stem cells that are still poorly understood. Skin epithelial stem cells represent a ripe target for research into the fundamental mechanisms underlying these important processes. PMID:12913119

  4. Epidermal Stem Cells in Orthopaedic Regenerative Medicine

    PubMed Central

    Li, Jin; Zhen, Gehua; Tsai, Shin-Yi; Jia, Xiaofeng

    2013-01-01

    In the last decade, great advances have been made in epidermal stem cell studies at the cellular and molecular level. These studies reported various subpopulations and differentiations existing in the epidermal stem cell. Although controversies and unknown issues remain, epidermal stem cells possess an immune-privileged property in transplantation together with easy accessibility, which is favorable for future clinical application. In this review, we will summarize the biological characteristics of epidermal stem cells, and their potential in orthopedic regenerative medicine. Epidermal stem cells play a critical role via cell replacement, and demonstrate significant translational potential in the treatment of orthopedic injuries and diseases, including treatment for wound healing, peripheral nerve and spinal cord injury, and even muscle and bone remodeling. PMID:23727934

  5. Transdifferentiation of Stem Cells: A Critical View

    NASA Astrophysics Data System (ADS)

    Gruh, Ina; Martin, Ulrich

    Recently a large amount of new data on the plasticity of stem cells of various lineages have emerged, providing new perspectives especially for the therapeutic application of adult stem cells. Previously unknown possibilities of cell differentiation beyond the known commitment of a given stem cell have been described using keywords such as "blood to liver," or "bone to brain." Controversies on the likelihood, as well as the biological significance, of these conversions almost immediately arose within this young field of stem cell biology. This chapter will concentrate on these controversies and focus on selected examples demonstrating the technical aspects of stem cell transdifferentiation and the evaluation of the tools used to analyze these events.

  6. 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.

  7. Signaling involved in stem cell reprogramming and differentiation

    PubMed Central

    Tanabe, Shihori

    2015-01-01

    Stem cell differentiation is regulated by multiple signaling events. Recent technical advances have revealed that differentiated cells can be reprogrammed into stem cells. The signals involved in stem cell programming are of major interest in stem cell research. The signaling mechanisms involved in regulating stem cell reprogramming and differentiation are the subject of intense study in the field of life sciences. In this review, the molecular interactions and signaling pathways related to stem cell differentiation are discussed. PMID:26328015

  8. [Generation of functional organs from pluripotent stem cells].

    PubMed

    Miyamoto, Tatsuyuki; Nakauchi, Hiromitsu

    2015-10-01

    Hematopoietic stem cells (HSCs) have played a major role in stem cell biology, providing many conceptual ideas and models. Among them is the concept of the "niche", a special bone-marrow microenvironment that by exchanging cues regulates stem-cell fate. The HSC niche also plays an important role in HSC transplantation. Successful engraftment of donor HSCs depends on myeloablative pretreatment to empty the niche. The concept of the stem-cell niche has now been extended to the generation of organs. We postulated that an empty "organ niche" exists in a developing animal when development of an organ is genetically disabled. This organ niche should be developmentally compensated by blastocyst complementation using wild-type primary stem cells (PSCs). We proved the principle of organogenesis from xenogeneic PSCs in an embryo unable to form a specific organ, demonstrating the generation of functionally normal rat pancreas by injecting rat PSCs into pancreatogenesis-disabled mouse embryos. This principle has held in pigs. When pancreatogenesis-disabled pig embryos underwent complementation with blastomeres from wild-type pig embryos to produce chimeric pigs, the chimeras had normal pancreata and survived to adulthood. Demonstration of the generation of a functional organ from PSCs in pigs is a very important step toward generation of human cells, tissues, and organs from individual patients' own PSCs in large animals. PMID:26458462

  9. Stem Cells for Cutaneous Wound Healing

    PubMed Central

    Kirby, Giles T. S.; Mills, Stuart J.; Cowin, Allison J.; Smith, Louise E.

    2015-01-01

    Optimum healing of a cutaneous wound involves a well-orchestrated cascade of biological and molecular processes involving cell migration, proliferation, extracellular matrix deposition, and remodelling. When the normal biological process fails for any reason, this healing process can stall resulting in chronic wounds. Wounds are a growing clinical burden on healthcare systems and with an aging population as well as increasing incidences of obesity and diabetes, this problem is set to increase. Cell therapies may be the solution. A range of cell based approaches have begun to cross the rift from bench to bedside and the supporting data suggests that the appropriate administration of stem cells can accelerate wound healing. This review examines the main cell types explored for cutaneous wound healing with a focus on clinical use. The literature overwhelmingly suggests that cell therapies can help to heal cutaneous wounds when used appropriately but we are at risk of clinical use outpacing the evidence. There is a need, now more than ever, for standardised methods of cell characterisation and delivery, as well as randomised clinical trials. PMID:26137471

  10. Advanced Properties of Urine Derived Stem Cells Compared to Adipose Tissue Derived Stem Cells in Terms of Cell Proliferation, Immune Modulation and Multi Differentiation.

    PubMed

    Kang, Hye Suk; Choi, Seock Hwan; Kim, Bum Soo; Choi, Jae Young; Park, Gang-Baek; Kwon, Tae Gyun; Chun, So Young

    2015-12-01

    Adipose tissue stem cells (ADSCs) would be an attractive autologous cell source. However, ADSCs require invasive procedures, and has potential complications. Recently, urine stem cells (USCs) have been proposed as an alternative stem cell source. In this study, we compared USCs and ADSCs collected from the same patients on stem cell characteristics and capacity to differentiate into various cell lineages to provide a useful guideline for selecting the appropriate type of cell source for use in clinical application. The urine samples were collected via urethral catheterization, and adipose tissue was obtained from subcutaneous fat tissue during elective laparoscopic kidney surgery from the same patient (n = 10). Both cells were plated for primary culture. Cell proliferation, colony formation, cell surface markers, immune modulation, chromosome stability and multi-lineage differentiation were analyzed for each USCs and ADSCs at cell passage 3, 5, and 7. USCs showed high cell proliferation rate, enhanced colony forming ability, strong positive for stem cell markers expression, high efficiency for inhibition of immune cell activation compared to ADSCs at cell passage 3, 5, and 7. In chromosome stability analysis, both cells showed normal karyotype through all passages. In analysis of multi-lineage capability, USCs showed higher myogenic, neurogenic, and endogenic differentiation rate, and lower osteogenic, adipogenic, and chondrogenic differentiation rate compared to ADSCs. Therefore, we expect that USC can be an alternative autologous stem cell source for muscle, neuron and endothelial tissue reconstruction instead of ADSCs.

  11. Advanced Properties of Urine Derived Stem Cells Compared to Adipose Tissue Derived Stem Cells in Terms of Cell Proliferation, Immune Modulation and Multi Differentiation

    PubMed Central

    2015-01-01

    Adipose tissue stem cells (ADSCs) would be an attractive autologous cell source. However, ADSCs require invasive procedures, and has potential complications. Recently, urine stem cells (USCs) have been proposed as an alternative stem cell source. In this study, we compared USCs and ADSCs collected from the same patients on stem cell characteristics and capacity to differentiate into various cell lineages to provide a useful guideline for selecting the appropriate type of cell source for use in clinical application. The urine samples were collected via urethral catheterization, and adipose tissue was obtained from subcutaneous fat tissue during elective laparoscopic kidney surgery from the same patient (n = 10). Both cells were plated for primary culture. Cell proliferation, colony formation, cell surface markers, immune modulation, chromosome stability and multi-lineage differentiation were analyzed for each USCs and ADSCs at cell passage 3, 5, and 7. USCs showed high cell proliferation rate, enhanced colony forming ability, strong positive for stem cell markers expression, high efficiency for inhibition of immune cell activation compared to ADSCs at cell passage 3, 5, and 7. In chromosome stability analysis, both cells showed normal karyotype through all passages. In analysis of multi-lineage capability, USCs showed higher myogenic, neurogenic, and endogenic differentiation rate, and lower osteogenic, adipogenic, and chondrogenic differentiation rate compared to ADSCs. Therefore, we expect that USC can be an alternative autologous stem cell source for muscle, neuron and endothelial tissue reconstruction instead of ADSCs. PMID:26713051

  12. Stem cell decisions: a twist of fate or a niche market?

    PubMed

    Januschke, Jens; Näthke, Inke

    2014-10-01

    Establishing and maintaining cell fate in the right place at the right time is a key requirement for normal tissue maintenance. Stem cells are at the core of this process. Understanding how stem cells balance self-renewal and production of differentiating cells is key for understanding the defects that underpin many diseases. Both, external cues from the environment and cell intrinsic mechanisms can control the outcome of stem cell division. The role of the orientation of stem cell division has emerged as an important mechanism for specifying cell fate decisions. Although, the alignment of cell divisions can dependent on spatial cues from the environment, maintaining stemness is not always linked to positioning of stem cells in a particular microenvironment or `niche'. Alternate mechanisms that could contribute to cellular memory include differential segregation of centrosomes in asymmetrically dividing cells. PMID:24613913

  13. Pathological modifications of plant stem cell destiny

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In higher plants, the shoot apex contains undifferentiated stem cells that give rise to various tissues and organs. The fate of these stem cells determines the pattern of plant growth as well as reproduction; and such fate is genetically preprogrammed. We found that a bacterial infection can derai...

  14. Skeletal stem cells in space and time.

    PubMed

    Kassem, Moustapha; Bianco, Paolo

    2015-01-15

    The nature, biological characteristics, and contribution to organ physiology of skeletal stem cells are not completely determined. Chan et al. and Worthley et al. demonstrate that a stem cell for skeletal tissues, and a system of more restricted, downstream progenitors, can be identified in mice and demonstrate its role in skeletal tissue maintenance and regeneration.

  15. Stem Cell Research and Health Education

    ERIC Educational Resources Information Center

    Eve, David J.; Marty, Phillip J.; McDermott, Robert J.; Klasko, Stephen K.; Sanberg, Paul R.

    2008-01-01

    Stem cells are being touted as the greatest discovery for the potential treatment of a myriad of diseases in the new millennium, but there is still much research to be done before it will be known whether they can live up to this description. There is also an ethical debate over the production of one of the most valuable types of stem cell: the…

  16. Improving Stem Cell Therapeutics with Mechanobiology.

    PubMed

    Shin, Jae-Won; Mooney, David J

    2016-01-01

    In recent years, it has become clear that mechanical cues play an integral role in maintaining stem cell functions. Here we discuss how integrating physical approaches and engineering principles in stem cell biology, including culture systems, preclinical models, and functional assessment, may improve clinical application in regenerative medicine.

  17. Stem Cell Fate Is a Touchy Subject.

    PubMed

    Smith, Quinton; Gerecht, Sharon

    2016-09-01

    Uncoupling synergistic interactions between physio-chemical cues that guide stem cell fate may improve efforts to direct their differentiation in culture. Using supramolecular hydrogels, Alakpa et al. (2016) demonstrate that mesenchymal stem cell differentiation is paired to depletion of bioactive metabolites, which can be utilized to chemically induce osteoblast and chondrocyte fate. PMID:27588745

  18. Engineering stem cells for future medicine.

    PubMed

    Ricotti, Leonardo; Menciassi, Arianna

    2013-03-01

    Despite their great potential in regenerative medicine applications, stem cells (especially pluripotent ones) currently show a limited clinical success, partly due to a lack of biological knowledge, but also due to a lack of specific and advanced technological instruments able to overcome the current boundaries of stem cell functional maturation and safe/effective therapeutic delivery. This paper aims at describing recent insights, current limitations, and future horizons related to therapeutic stem cells, by analyzing the potential of different bioengineering disciplines in bringing stem cells toward a safe clinical use. First, we clarify how and why stem cells should be properly engineered and which could be in a near future the challenges and the benefits connected with this process. Second, we identify different routes toward stem cell differentiation and functional maturation, relying on chemical, mechanical, topographical, and direct/indirect physical stimulation. Third, we highlight how multiscale modeling could strongly support and optimize stem cell engineering. Finally, we focus on future robotic tools that could provide an added value to the extent of translating basic biological knowledge into clinical applications, by developing ad hoc enabling technologies for stem cell delivery and control.

  19. Epithelial Sodium Channels in Pulmonary Epithelial Progenitor and Stem Cells

    PubMed Central

    Liu, Yang; Jiang, Bi-Jie; Zhao, Run-Zhen; Ji, Hong-Long

    2016-01-01

    Regeneration of the epithelium of mammalian lungs is essential for restoring normal function following injury, and various cells and mechanisms contribute to this regeneration and repair. Club cells, bronchioalveolar stem cells (BASCs), and alveolar type II epithelial cells (ATII) are dominant stem/progenitor cells for maintaining epithelial turnover and repair. Epithelial Na+ channels (ENaC), a critical pathway for transapical salt and fluid transport, are expressed in lung epithelial progenitors, including club and ATII cells. Since ENaC activity and expression are development- and differentiation-dependent, apically located ENaC activity has therefore been used as a functional biomarker of lung injury repair. ENaC activity may be involved in the migration and differentiation of local and circulating stem/progenitor cells with diverse functions, eventually benefiting stem cells spreading to re-epithelialize injured lungs. This review summarizes the potential roles of ENaC expressed in native progenitor and stem cells in the development and regeneration of the respiratory epithelium. PMID:27570489

  20. Epithelial Sodium Channels in Pulmonary Epithelial Progenitor and Stem Cells.

    PubMed

    Liu, Yang; Jiang, Bi-Jie; Zhao, Run-Zhen; Ji, Hong-Long

    2016-01-01

    Regeneration of the epithelium of mammalian lungs is essential for restoring normal function following injury, and various cells and mechanisms contribute to this regeneration and repair. Club cells, bronchioalveolar stem cells (BASCs), and alveolar type II epithelial cells (ATII) are dominant stem/progenitor cells for maintaining epithelial turnover and repair. Epithelial Na(+) channels (ENaC), a critical pathway for transapical salt and fluid transport, are expressed in lung epithelial progenitors, including club and ATII cells. Since ENaC activity and expression are development- and differentiation-dependent, apically located ENaC activity has therefore been used as a functional biomarker of lung injury repair. ENaC activity may be involved in the migration and differentiation of local and circulating stem/progenitor cells with diverse functions, eventually benefiting stem cells spreading to re-epithelialize injured lungs. This review summarizes the potential roles of ENaC expressed in native progenitor and stem cells in the development and regeneration of the respiratory epithelium. PMID:27570489

  1. Cancer stem cell: fundamental experimental pathological concepts and updates.

    PubMed

    Islam, Farhadul; Qiao, Bin; Smith, Robert A; Gopalan, Vinod; Lam, Alfred K-Y

    2015-04-01

    Cancer stem cells (CSCs) are a subset of cancer cells which play a key role in predicting the biological aggressiveness of cancer due to its ability of self-renewal and multi-lineage differentiation (stemness). The CSC model is a dynamic one with a functional subpopulation of cancer cells rather than a stable cell population responsible for tumour regeneration. Hypotheses regarding the origins of CSCs include (1) malignant transformation of normal stem cells; (2) mature cancer cell de-differentiation with epithelial-mesenchymal transition and (3) induced pluripotent cancer cells. Surprisingly, the cancer stem cell hypothesis originated in the late nineteenth century and the existence of haematopoietic stem cells was demonstrated a century later, demonstrating that the concept was possible. In the last decade, CSCs have been identified and isolated in different cancers. The hallmark traits of CSCs include their heterogeneity, interaction with microenvironments and plasticity. Understanding these basic concepts of CSCs is important for translational applications using CSCs in the management of patients with cancer. PMID:25659759

  2. Stem Cell Research: Unlocking the Mystery of Disease

    MedlinePlus

    ... Home Current Issue Past Issues From the Director: Stem Cell Research: Unlocking the Mystery of Disease Past Issues / Summer ... Zerhouni, NIH Director, described the need for expanding stem cell research. Recently, he spoke about stem cell research with ...

  3. Organ or Stem Cell Transplant and Your Mouth

    MedlinePlus

    ... Stem Cell Transplant and Your Mouth Organ or Stem Cell Transplant and Your Mouth Main Content Key Points​ ... Your Dentist Before Transplant Before an organ or stem cell transplant, have a dental checkup. Your mouth should ...

  4. Human-Mouse Chimerism Validates Human Stem Cell Pluripotency.

    PubMed

    Mascetti, Victoria L; Pedersen, Roger A

    2016-01-01

    Pluripotent stem cells are defined by their capacity to differentiate into all three tissue layers that comprise the body. Chimera formation, generated by stem cell transplantation to the embryo, is a stringent assessment of stem cell pluripotency. However, the ability of human pluripotent stem cells (hPSCs) to form embryonic chimeras remains in question. Here we show using a stage-matching approach that human induced pluripotent stem cells (hiPSCs) and human embryonic stem cells (hESCs) have the capacity to participate in normal mouse development when transplanted into gastrula-stage embryos, providing in vivo functional validation of hPSC pluripotency. hiPSCs and hESCs form interspecies chimeras with high efficiency, colonize the embryo in a manner predicted from classical developmental fate mapping, and differentiate into each of the three primary tissue layers. This faithful recapitulation of tissue-specific fate post-transplantation underscores the functional potential of hPSCs and provides evidence that human-mouse interspecies developmental competency can occur.

  5. EMPOWERING ADULT STEM CELLS FOR MYOCARDIAL REGENERATION

    PubMed Central

    Mohsin, Sadia; Siddiqi, Sailay; Collins, Brett; Sussman, Mark A.

    2012-01-01

    Treatment strategies for heart failure remain a high priority for ongoing research due to the profound unmet need in clinical disease coupled with lack of significant translational progress. The underlying issue is the same whether the cause is acute damage, chronic stress from disease, or aging: progressive loss of functional cardiomyocytes and diminished hemodynamic output. To stave off cardiomyocyte losses, a number of strategic approaches have been embraced in recent years involving both molecular and cellular approaches to augment myocardial structure and performance. Resultant excitement surrounding regenerative medicine in the heart has been tempered by realizations that reparative processes in the heart are insufficient to restore damaged myocardium to normal functional capacity and that cellular cardiomyoplasty is hampered by poor survival, proliferation, engraftment and differentiation of the donated population. To overcome these limitations, a combination of molecular and cellular approaches needs to be adopted involving use of genetic engineering to enhance resistance to cell death and increase regenerative capacity. This review will highlight biological properties of approached to potentiate stem cell-mediated regeneration to promote enhanced myocardial regeneration, persistence of donated cells, and long lasting tissue repair. Optimizing cell delivery and harnessing the power of survival signaling cascades for ex vivo genetic modification of stem cells prior to reintroduction into the patient will be critical to enhance the efficacy of cellular cardiomyoplasty. Once this goal is achieved, then cell-based therapy has great promise for treatment of heart failure to combat the loss of cardiac structure and function associated with acute damage, chronic disease or aging. PMID:22158649

  6. Impact of retrotransposons in pluripotent stem cells.

    PubMed

    Tanaka, Yoshiaki; Chung, Leeyup; Park, In-Hyun

    2012-12-01

    Retrotransposons, which constitute approximately 40% of the human genome, have the capacity to 'jump' across the genome. Their mobility contributes to oncogenesis, evolution, and genomic plasticity of the host genome. Induced pluripotent stem cells as well as embryonic stem cells are more susceptible than differentiated cells to genomic aberrations including insertion, deletion and duplication. Recent studies have revealed specific behaviors of retrotransposons in pluripotent cells. Here, we review recent progress in understanding retrotransposons and provide a perspective on the relationship between retrotransposons and genomic variation in pluripotent stem cells. PMID:23135636

  7. Artificial gametes from stem cells

    PubMed Central

    Moreno, Inmaculada; Míguez-Forjan, Jose Manuel

    2015-01-01

    The generation of artificial gametes is a real challenge for the scientific community today. In vitro development of human eggs and sperm will pave the way for the understanding of the complex process of human gametogenesis and will provide with human gametes for the study of infertility and the onset of some inherited disorders. However, the great promise of artificial gametes resides in their future application on reproductive treatments for all these people wishing to have genetically related children and for which gamete donation is now their unique option of parenthood. This is the case of infertile patients devoid of suitable gametes, same sex couples, singles and those fertile couples in a high risk of transmitting serious diseases to their progeny. In the search of the best method to obtain artificial gametes, many researchers have successfully obtained human germ cell-like cells from stem cells at different stages of differentiation. In the near future, this field will evolve to new methods providing not only viable but also functional and safe artificial germ cells. These artificial sperm and eggs should be able to recapitulate all the genetic and epigenetic processes needed for the correct gametogenesis, fertilization and embryogenesis leading to the birth of a healthy and fertile newborn. PMID:26161331

  8. Overcoming Multidrug Resistance in Cancer Stem Cells

    PubMed Central

    Moitra, Karobi

    2015-01-01

    The principle mechanism of protection of stem cells is through the expression of ATP-binding cassette (ABC) transporters. These transporters serve as the guardians of the stem cell population in the body. Unfortunately these very same ABC efflux pumps afford protection to cancer stem cells in tumors, shielding them from the adverse effects of chemotherapy. A number of strategies to circumvent the function of these transporters in cancer stem cells are currently under investigation. These strategies include the development of competitive and allosteric modulators, nanoparticle mediated delivery of inhibitors, targeted transcriptional regulation of ABC transporters, miRNA mediated inhibition, and targeting of signaling pathways that modulate ABC transporters. The role of ABC transporters in cancer stem cells will be explored in this paper and strategies aimed at overcoming drug resistance caused by these particular transporters will also be discussed. PMID:26649310

  9. Biophysical regulation of stem cell differentiation.

    PubMed

    Govey, Peter M; Loiselle, Alayna E; Donahue, Henry J

    2013-06-01

    Bone adaptation to its mechanical environment, from embryonic through adult life, is thought to be the product of increased osteoblastic differentiation from mesenchymal stem cells. In parallel with tissue-scale loading, these heterogeneous populations of multipotent stem cells are subject to a variety of biophysical cues within their native microenvironments. Bone marrow-derived mesenchymal stem cells-the most broadly studied source of osteoblastic progenitors-undergo osteoblastic differentiation in vitro in response to biophysical signals, including hydrostatic pressure, fluid flow and accompanying shear stress, substrate strain and stiffness, substrate topography, and electromagnetic fields. Furthermore, stem cells may be subject to indirect regulation by mechano-sensing osteocytes positioned to more readily detect these same loading-induced signals within the bone matrix. Such paracrine and juxtacrine regulation of differentiation by osteocytes occurs in vitro. Further studies are needed to confirm both direct and indirect mechanisms of biophysical regulation within the in vivo stem cell niche.

  10. [Stem cells--cloning, plasticity, bioethic].

    PubMed

    Pflegerl, Pamina; Keller, Thomas; Hantusch, Brigitte; Hoffmann, Thomas Sören; Kenner, Lukas

    2008-01-01

    Stem cells with certain characteristics have become promising tools for molecular medicine. They have the potential to self-regenerate and to differentiate into specific tissues. Besides their great potential, embryonic stem cells (ESC) run the risk of enhanced tumorigenesis. The use of human embryonic stem cells (hESC) is ethically problematic because their isolation involves the destruction of human embryos. Recently developed methods generate are able to pluripotent stem cells from fibroblasts. Alternatives for ESC are adult stem cells (ASC) derived from bone marrow, cord blood, amniotic fluid and other tissues. The following article is on the basis of testimony of Lukas Kenner for the German Bundestag about the use of ESC for research, therapy and drug development. Ethical aspects are taken into consideration.

  11. Are stem cells a cure for diabetes?

    PubMed

    McCall, Michael D; Toso, Christian; Baetge, Emmanuel E; Shapiro, A M James

    2010-01-01

    With the already heightened demand placed on organ donation, stem cell therapy has become a tantalizing idea to provide glucose-responsive insulin-producing cells to Type 1 diabetic patients as an alternative to islet transplantation. Multiple groups have developed varied approaches to create a population of cells with the appropriate characteristics. Both adult and embryonic stem cells have received an enormous amount of attention as possible sources of insulin-producing cells. Although adult stem cells lack the pluripotent nature of their embryonic counterparts, they appear to avoid the ethical debate that has centred around the latter. This may limit the eventual application of embryonic stem cells, which have already shown promise in early mouse models. One must also consider the potential of stem cells to form teratomas, a complication which would prove devastating in an immunologically compromised transplant recipient. The present review looks at the progress to date in both the adult and embryonic stem cells fields as potential treatments for diabetes. We also consider some of the limitations of stem cell therapy and the potential complications that may develop with their use. PMID:19807695

  12. Translational research of adult stem cell therapy.

    PubMed

    Suzuki, Gen

    2015-11-26

    Congestive heart failure (CHF) secondary to chronic coronary artery disease is a major cause of morbidity and mortality world-wide. Its prevalence is increasing despite advances in medical and device therapies. Cell based therapies generating new cardiomyocytes and vessels have emerged as a promising treatment to reverse functional deterioration and prevent the progression to CHF. Functional efficacy of progenitor cells isolated from the bone marrow and the heart have been evaluated in preclinical large animal models. Furthermore, several clinical trials using autologous and allogeneic stem cells and progenitor cells have demonstrated their safety in humans yet their clinical relevance is inconclusive. This review will discuss the clinical therapeutic applications of three specific adult stem cells that have shown particularly promising regenerative effects in preclinical studies, bone marrow derived mesenchymal stem cell, heart derived cardiosphere-derived cell and cardiac stem cell. We will also discuss future therapeutic approaches.

  13. Breast cancer stem cells and radiation

    NASA Astrophysics Data System (ADS)

    Phillips, Tiffany Marie

    2007-12-01

    The present studies explore the response of breast cancer stem cells (BCSC's) to radiation and the implications for clinical cancer treatment. Current cancer therapy eliminates bulky tumor mass but may fail to eradicate a critical tumor initiating cell population termed "cancer stem cells". These cells are potentially responsible for tumor formation, metastasis, and recurrence. Recently cancer stem cells have been prospectively identified in various malignancies, including breast cancer. The breast cancer stem cell has been identified by the surface markers CD44+/CD24 -(low). In vitro mammosphere cultures allow for the enrichment of the cancer stem cell population and were utilized in order to study differential characteristics of BCSC's. Initial studies found that BCSC's display increased radiation resistance as compared to other non-stem tumor cells. This resistance was accompanied by decreased H2AX phosphorylation, decreased reactive oxygen species formation, and increased phosphorylation of the checkpoint protein Chk1. These studies suggest differential DNA damage and repair within the BCSC population. Studies then examined the consequences of fractionated radiation on the BCSC population and found a two-fold increase in BCSC's following 5 x 3Gy. This observation begins to tie cancer stem cell self-renewal to the clinical stem cell phenomenon of accelerated repopulation. Accelerated repopulation is observed when treatment gaps increase between sequential fractions of radiotherapy and may be due to cancer stem cell symmetric self-renewal. The balance between asymmetric and symmetric stem cell division is vital for proper maintenance; deregulation is likely linked to cancer initiation and progression. The developmental Notch-1 pathway was found to regulate BCSC division. Over-expressing the constitutively active Notch-1-ICD in MCF7 cells produced an increase in the BCSC population. Additionally, radiation was observed to increase the expression of the Notch-1

  14. 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.

  15. The Endocrine Regulation of Stem Cells: Physiological Importance and Pharmacological Potentials for Cell-Based Therapy.

    PubMed

    Ghorbani, Ahmad; Naderi-Meshkin, Hojjat

    2016-01-01

    Throughout life, different types of stem cells participate in tissue generation, maintenance, plasticity, and repair. Their abilities to secrete growth factors, to proliferate and differentiate into several cell lineages, and to migrate and home into the damaged tissues have made them attractive candidates for cell therapy and tissue engineering applications. Normal stem cell function is tied to the cell-intrinsic mechanisms and extrinsic signals derived from the surrounding microenvironment or circulation. Understanding the regulatory signals that govern stem cell functions is essential in order to have full knowledge about organogenesis, tissue maintenance and tissue plasticity in the physiological condition. It is also important for optimizing tissue engineering and improving the therapeutic efficiency of stem cells in regenerative medicine. A growing body of evidence indicates that hormonal signals can critically influence stem cell functions in fetal, postnatal, and adult tissues. This review focuses on recent studies revealing how growth hormone, insulin, thyroid hormone, parathormone, adrenocorticotropin, glucocorticoids, erythropoietin, and gastrointestinal hormones control stem cell behavior through influencing survival, proliferation, migration, homing, and differentiation of these cells. Moreover, how environmental factors such as exercise, hypoxia, and nutrition might affect stem cell functions through influencing the endocrine system is discussed. Some of the current limitations of cell therapy and how hormones can help overcoming these limitations are briefly outlined.

  16. The Endocrine Regulation of Stem Cells: Physiological Importance and Pharmacological Potentials for Cell-Based Therapy.

    PubMed

    Ghorbani, Ahmad; Naderi-Meshkin, Hojjat

    2016-01-01

    Throughout life, different types of stem cells participate in tissue generation, maintenance, plasticity, and repair. Their abilities to secrete growth factors, to proliferate and differentiate into several cell lineages, and to migrate and home into the damaged tissues have made them attractive candidates for cell therapy and tissue engineering applications. Normal stem cell function is tied to the cell-intrinsic mechanisms and extrinsic signals derived from the surrounding microenvironment or circulation. Understanding the regulatory signals that govern stem cell functions is essential in order to have full knowledge about organogenesis, tissue maintenance and tissue plasticity in the physiological condition. It is also important for optimizing tissue engineering and improving the therapeutic efficiency of stem cells in regenerative medicine. A growing body of evidence indicates that hormonal signals can critically influence stem cell functions in fetal, postnatal, and adult tissues. This review focuses on recent studies revealing how growth hormone, insulin, thyroid hormone, parathormone, adrenocorticotropin, glucocorticoids, erythropoietin, and gastrointestinal hormones control stem cell behavior through influencing survival, proliferation, migration, homing, and differentiation of these cells. Moreover, how environmental factors such as exercise, hypoxia, and nutrition might affect stem cell functions through influencing the endocrine system is discussed. Some of the current limitations of cell therapy and how hormones can help overcoming these limitations are briefly outlined. PMID:26337380

  17. Human adipose stem cells: current clinical applications.

    PubMed

    Gir, Phanette; Oni, Georgette; Brown, Spencer A; Mojallal, Ali; Rohrich, Rod J

    2012-06-01

    Adipose-derived stem cells are multipotent cells that can easily be extracted from adipose tissue, are capable of expansion in vitro, and have the capacity to differentiate into multiple cell lineages, which have the potential for use in regenerative medicine. However, several issues need to be studied to determine safe human use. For example, there are questions related to isolation and purification of adipose-derived stem cells, their effect on tumor growth, and the enforcement of U.S. Food and Drug Administration regulations. Numerous studies have been published, with the interest in the potential for regenerative medicine continually growing. Several clinical trials using human adipose stem cell therapy are currently being performed around the world, and there has been a rapid evolution and expansion of their number. The purpose of this article was to review the current published basic science evidence and ongoing clinical trials involving the use of adipose-derived stem cells in plastic surgery and in regenerative medicine in general. The results of the studies and clinical trials using adipose-derived stem cells reported in this review seem to be promising not only in plastic surgery but also in a wide variety of other specialties. Nevertheless, those reported showed disparity in the way adipose-derived stem cells were used. Further basic science experimental studies with standardized protocols and larger randomized trials need to be performed to ensure safety and efficacy of adipose-derived stem cells use in accordance with U.S. Food and Drug Administration guidelines.

  18. [Stem cells: limitations and opportunities in Peru].

    PubMed

    Amiel-Pérez, José; Casado, Fanny

    2015-10-01

    Stem cells are defined as rare cells that are characterized by asymmetric division, a process known as self-renewal, and the potential to differentiate into more than one type of terminally differentiated cell. There is a diversity of stem cells including embryonic stem cells, which exist only during the first stages of human development, and many adult stem cells depending on the specific tissues from where they derive or the ones derived from mesenchymal or stromal tissues. On the other hand, there are induced pluripotent stem cells generated by genetic engineering with similar properties to embryonic stem cells that are derived from adult tissues without the ethical and legal limitations. In all cases, there are many questions that are being addressed by research in basic sciences to better inform clinical practice. In Peru, there is much to do refining techniques and improving methodologies, which requires experience, proper facilities and highly specialized human resources. However, there are interesting efforts to place Peruvian stem cell research in the international scientific arena.

  19. Cancer stem cells niche: a target for novel cancer therapeutics.

    PubMed

    Yi, Shan-Yong; Hao, Yi-Bin; Nan, Ke-Jun; Fan, Tian-Li

    2013-05-01

    Nowadays, cancer has been a frequent disease, and the first or second most common cause of death worldwide. Despite a better understanding of the biology of cancer cells, the therapy of most cancers has not significantly changed for the past four decades. It is because conventional chemotherapies and/or radiation therapies are usually designed to eradicate highly proliferative cells. Mounting evidence has implicated that cancer is a disease of stem cells. Cancer stem cells (CSC) are often relatively quiescent, and therefore may not be affected by therapies targeting rapidly dividing cells. Like normal stem cells (NSC) residing in a "stem cell niche" that maintains them in a stem-like state, CSC also require a special microenvironment to control their self-renewal and undifferentiated state. The "CSC niche" is likely to be the most crucial target in the treatment of cancer. In this article, we summarize the current knowledge regarding CSC and their niche microenvironments. Understanding of CSC's origin, molecular profile, and interaction with their microenvironments, this could be a paradigm shift in the treatment of cancer, away from targeting the blast cells and towards the targeting of the CSC, thus improving therapeutic outcome.

  20. High Throughput Optimization of Stem Cell Microenvironments

    PubMed Central

    Yang, Fan; Mei, Ying; Langer, Robert; Anderson, Daniel G.

    2009-01-01

    Stem cells have great potential as cell sources for regenerative medicine due to both their self-renewal and multi-lineage differentiation capacity. Despite advances in the field of stem cell biology, major challenges remain before stem cells can be widely used for therapeutic purposes. One challenge is to develop reproducible methods to control stem cell growth and differentiation. The niche in which stem cells reside is a complex, multi-factorial environment. In contrast to using cells alone, biomaterials can provide initial structural support, and allow cells to adhere, proliferate and differentiate in a three-dimensional environment. Researchers have incorporated signals into the biomaterials that can promote desired cell functions in a spatially and temporally controlled manner. Despite progress in biomaterial design and methods to modulate cellular behavior, many of the complex signal networks that regulate cell-material interactions remain unclear. Due to the vast numbers of material properties to be explored and the complexity of cell-surface interactions, it is often difficult to optimize stem cell microenvironments using conventional, iterative approaches. To address these challenges, high throughput screening of combinatorial libraries has emerged as a novel approach to achieve rapid screening with reduced materials and costs. In this review, we discuss recent research in the area of high throughput approaches for characterization and optimization of cellular interactions with their microenvironments. In contrast to conventional approaches, screening combinatorial libraries can result in the discovery of unexpected material solutions to these complex problems. PMID:19601753

  1. Connecting Mitochondria, Metabolism, and Stem Cell Fate

    PubMed Central

    Wanet, Anaïs; Arnould, Thierry; Najimi, Mustapha

    2015-01-01

    As sites of cellular respiration and energy production, mitochondria play a central role in cell metabolism. Cell differentiation is associated with an increase in mitochondrial content and activity and with a metabolic shift toward increased oxidative phosphorylation activity. The opposite occurs during reprogramming of somatic cells into induced pluripotent stem cells. Studies have provided evidence of mitochondrial and metabolic changes during the differentiation of both embryonic and somatic (or adult) stem cells (SSCs), such as hematopoietic stem cells, mesenchymal stem cells, and tissue-specific progenitor cells. We thus propose to consider those mitochondrial and metabolic changes as hallmarks of differentiation processes. We review how mitochondrial biogenesis, dynamics, and function are directly involved in embryonic and SSC differentiation and how metabolic and sensing pathways connect mitochondria and metabolism with cell fate and pluripotency. Understanding the basis of the crosstalk between mitochondria and cell fate is of critical importance, given the promising application of stem cells in regenerative medicine. In addition to the development of novel strategies to improve the in vitro lineage-directed differentiation of stem cells, understanding the molecular basis of this interplay could lead to the identification of novel targets to improve the treatment of degenerative diseases. PMID:26134242

  2. Connecting Mitochondria, Metabolism, and Stem Cell Fate.

    PubMed

    Wanet, Anaïs; Arnould, Thierry; Najimi, Mustapha; Renard, Patricia

    2015-09-01

    As sites of cellular respiration and energy production, mitochondria play a central role in cell metabolism. Cell differentiation is associated with an increase in mitochondrial content and activity and with a metabolic shift toward increased oxidative phosphorylation activity. The opposite occurs during reprogramming of somatic cells into induced pluripotent stem cells. Studies have provided evidence of mitochondrial and metabolic changes during the differentiation of both embryonic and somatic (or adult) stem cells (SSCs), such as hematopoietic stem cells, mesenchymal stem cells, and tissue-specific progenitor cells. We thus propose to consider those mitochondrial and metabolic changes as hallmarks of differentiation processes. We review how mitochondrial biogenesis, dynamics, and function are directly involved in embryonic and SSC differentiation and how metabolic and sensing pathways connect mitochondria and metabolism with cell fate and pluripotency. Understanding the basis of the crosstalk between mitochondria and cell fate is of critical importance, given the promising application of stem cells in regenerative medicine. In addition to the development of novel strategies to improve the in vitro lineage-directed differentiation of stem cells, understanding the molecular basis of this interplay could lead to the identification of novel targets to improve the treatment of degenerative diseases.

  3. Induced pluripotent stem cells from goat fibroblasts.

    PubMed

    Song, Hui; Li, Hui; Huang, Mingrui; Xu, Dan; Gu, Chenghao; Wang, Ziyu; Dong, Fulu; Wang, Feng

    2013-12-01

    Embryonic stem cells (ESCs) are a powerful model for genetic engineering, studying developmental biology, and modeling disease. To date, ESCs have been established from the mouse (Evans and Kaufman, 1981, Nature 292:154-156), non-human primates (Thomson et al., , Proc Nat Acad Sci USA 92:7844-7848), humans (Thomson et al., 1998, Science 282:1145-1147), and rats (Buehr et al., , Cell 135:1287-1298); however, the derivation of ESCs from domesticated ungulates such as goats, sheep, cattle, and pigs have not been successful. Alternatively, induced pluripotent stem cells (iPSCs) can be generated by reprogramming somatic cells with several combinations of genes encoding transcription factors (OCT3/4, SOX2, KLF4, cMYC, LIN28, and NANOG). To date, iPSCs have been isolated from various species, but only limited information is available regarding goat iPSCs (Ren et al., 2011, Cell Res 21:849-853). The objectives of this study were to generate goat iPSCs from fetal goat primary ear fibroblasts using lentiviral transduction of four human transcription factors: OCT4, SOX2, KLF4, and cMYC. The goat iPSCs were successfully generated by co-culture with mitomycin C-treated mouse embryonic fibroblasts using medium supplemented with knockout serum replacement and human basic fibroblast growth factor. The goat iPSCs colonies are flat, compact, and closely resemble human iPSCs. They have a normal karyotype; stain positive for alkaline phosphatase, OCT4, and NANOG; express endogenous pluripotency genes (OCT4, SOX2, cMYC, and NANOG); and can spontaneously differentiate into three germ layers in vitro and in vivo. PMID:24123501

  4. Induced pluripotent stem cells from goat fibroblasts.

    PubMed

    Song, Hui; Li, Hui; Huang, Mingrui; Xu, Dan; Gu, Chenghao; Wang, Ziyu; Dong, Fulu; Wang, Feng

    2013-12-01

    Embryonic stem cells (ESCs) are a powerful model for genetic engineering, studying developmental biology, and modeling disease. To date, ESCs have been established from the mouse (Evans and Kaufman, 1981, Nature 292:154-156), non-human primates (Thomson et al., , Proc Nat Acad Sci USA 92:7844-7848), humans (Thomson et al., 1998, Science 282:1145-1147), and rats (Buehr et al., , Cell 135:1287-1298); however, the derivation of ESCs from domesticated ungulates such as goats, sheep, cattle, and pigs have not been successful. Alternatively, induced pluripotent stem cells (iPSCs) can be generated by reprogramming somatic cells with several combinations of genes encoding transcription factors (OCT3/4, SOX2, KLF4, cMYC, LIN28, and NANOG). To date, iPSCs have been isolated from various species, but only limited information is available regarding goat iPSCs (Ren et al., 2011, Cell Res 21:849-853). The objectives of this study were to generate goat iPSCs from fetal goat primary ear fibroblasts using lentiviral transduction of four human transcription factors: OCT4, SOX2, KLF4, and cMYC. The goat iPSCs were successfully generated by co-culture with mitomycin C-treated mouse embryonic fibroblasts using medium supplemented with knockout serum replacement and human basic fibroblast growth factor. The goat iPSCs colonies are flat, compact, and closely resemble human iPSCs. They have a normal karyotype; stain positive for alkaline phosphatase, OCT4, and NANOG; express endogenous pluripotency genes (OCT4, SOX2, cMYC, and NANOG); and can spontaneously differentiate into three germ layers in vitro and in vivo.

  5. Can Nanomedicines Kill Cancer Stem Cells?

    PubMed Central

    Zhao, Yi; Alakhova, Daria Y.; Kabanov, Alexander V.

    2014-01-01

    Most tumors are heterogeneous and many cancers contain small population of highly tumorigenic and intrinsically drug resistant cancer stem cells (CSCs). Like normal stem cell, CSCs have ability to self-renew and differentiate to other tumor cell types. They are believed to be a source for drug resistance, tumor recurrence and metastasis. CSCs often overexpress drug efflux transporters, spend most of their time in non-dividing G0 cell cycle state, and therefore, can escape the conventional chemotherapies. Thus, targeting CSCs is essential for developing novel therapies to prevent cancer relapse and emerging of drug resistance. Nanocarrier-based therapeutic agents (nanomedicines) have been used to achieve longer circulation times, better stability and bioavailability over current therapeutics. Recently, some groups have successfully applied nanomedicines to target CSCs to eliminate the tumor and prevent its recurrence. These approaches include 1) delivery of therapeutic agents (small molecules, siRNA, antibodies) that affect embryonic signaling pathways implicated in self-renewal and differentiation in CSCs, 2) inhibiting drug efflux transporters in an attempt to sensitize CSCs to therapy, 3) targeting metabolism in CSCs through nanoformulated chemicals and field-responsive magnetic nanoparticles and carbon nanotubes, and 4) disruption of multiple pathways in drug resistant cells using combination of chemotherapeutic drugs with amphiphilic Pluronic block copolymers. Despite clear progress of these studies the challenges of targeting CSCs by nanomedicines still exist and leave plenty of room for improvement and development. This review summarizes biological processes that are related to CSCs, overviews the current state of anti-CSCs therapies, and discusses state-of-the-art nanomedicine approaches developed to kill CSCs. PMID:24120657

  6. Stem cells and small molecule screening: haploid embryonic stem cells as a new tool.

    PubMed

    Wu, Bi; Li, Wei; Wang, Liu; Liu, Zhong-hua; Zhao, Xiao-yang

    2013-06-01

    Stem cells can both self-renew and differentiate into various cell types under certain conditions, which makes them a good model for development and disease studies. Recently, chemical approaches have been widely applied in stem cell biology by promoting stem cell self-renewal, proliferation, differentiation and somatic cell reprogramming using specific small molecules. Conversely, stem cells and their derivatives also provide an efficient and robust platform for small molecule and drug screening. Here, we review the current research and applications of small molecules that modulate stem cell self-renewal and differentiation and improve reprogramming, as well as the applications that use stem cells as a tool for small molecule screening. Moreover, we introduce the recent advance in haploid embryonic stem cells research. Haploid embryonic stem cells maintain haploidy and stable growth over extensive passages, possess the ability to differentiate into all three germ layers in vitro and in vivo, and contribute to the germlines of chimeras when injected into blastocysts. Androgenetic haploid stem cells can also be used in place of sperm to produce fertile progeny after intracytoplasmic injection into mature oocytes. Such characteristics demonstrate that haploid stem cells are a new approach for genetic studies at both the cellular and animal levels and that they are a valuable platform for future small molecule screening.

  7. Bioreactor Engineering of Stem Cell Environments

    PubMed Central

    Tandon, Nina; Marolt, Darja; Cimetta, Elisa; Vunjak-Novakovic, Gordana

    2013-01-01

    Stem cells hold promise to revolutionize modern medicine by development of new therapies, disease models and drug screening systems. Standard cell culture systems have limited biological relevance because they do not recapitulate the complex 3-dimensional interactions and biophysical cues that characterize the in vivo environment. In this review, we discuss the current advances in engineering stem cell environments using novel biomaterials and bioreactor technologies. We also reflect on the challenges the field is currently facing with regard to translation of stem cell based therapies into the clinic. PMID:23531529

  8. Update on small intestinal stem cells

    PubMed Central

    Tesori, Valentina; Puglisi, Maria Ausiliatrice; Lattanzi, Wanda; Gasbarrini, Giovanni Battista; Gasbarrini, Antonio

    2013-01-01

    Among somatic stem cells, those residing in the intestine represent a fascinating and poorly explored research field. Particularly, somatic stem cells reside in the small intestine at the level of the crypt base, in a constant balance between self-renewal and differentiation. Aim of the present review is to delve into the mechanisms that regulate the delicate equilibrium through which intestinal stem cells orchestrate intestinal architecture. To this aim, special focus will be addressed to identify the integrating signals from the surrounding niche, supporting a model whereby distinct cell populations facilitate homeostatic vs injury-induced regeneration. PMID:23922464

  9. Stem cell applications in military medicine.

    PubMed

    Christopherson, Gregory T; Nesti, Leon J

    2011-10-19

    There are many similarities between health issues affecting military and civilian patient populations, with the exception of the relatively small but vital segment of active soldiers who experience high-energy blast injuries during combat. A rising incidence of major injuries from explosive devices in recent campaigns has further complicated treatment and recovery, highlighting the need for tissue regenerative options and intensifying interest in the possible role of stem cells for military medicine. In this review we outline the array of tissue-specific injuries typically seen in modern combat - as well as address a few complications unique to soldiers--and discuss the state of current stem cell research in addressing each area. Embryonic, induced-pluripotent and adult stem cell sources are defined, along with advantages and disadvantages unique to each cell type. More detailed stem cell sources are described in the context of each tissue of interest, including neural, cardiopulmonary, musculoskeletal and sensory tissues, with brief discussion of their potential role in regenerative medicine moving forward. Additional commentary is given to military stem cell applications aside from regenerative medicine, such as blood pharming, immunomodulation and drug screening, with an overview of stem cell banking and the unique opportunity provided by the military and civilian overlap of stem cell research.

  10. Current understanding concerning intestinal stem cells

    PubMed Central

    Cui, Shuang; Chang, Peng-Yu

    2016-01-01

    In mammals, the intestinal epithelium is a tissue that contains two distinct pools of stem cells: active intestinal stem cells and reserve intestinal stem cells. The former are located in the crypt basement membrane and are responsible for maintaining epithelial homeostasis under intact conditions, whereas the latter exhibit the capacity to facilitate epithelial regeneration after injury. These two pools of cells can convert into each other, maintaining their quantitative balance. In terms of the active intestinal stem cells, their development into functional epithelium is precisely controlled by the following signaling pathways: Wnt/β-catenin, Ras/Raf/Mek/Erk/MAPK, Notch and BMP/Smad. However, mutations in some of the key regulator genes associated with these signaling pathways, such as APC, Kras and Smad4, are also highly associated with gut malformations. At this point, clarifying the biological characteristics of intestinal stem cells will increase the feasibility of preventing or treating some intestinal diseases, such as colorectal cancer. Moreover, as preclinical data demonstrate the therapeutic effects of colon stem cells on murine models of experimental colitis, the prospects of stem cell-based regenerative treatments for ulcerous lesions in the gastrointestinal tract will be improved all the same.

  11. Current understanding concerning intestinal stem cells

    PubMed Central

    Cui, Shuang; Chang, Peng-Yu

    2016-01-01

    In mammals, the intestinal epithelium is a tissue that contains two distinct pools of stem cells: active intestinal stem cells and reserve intestinal stem cells. The former are located in the crypt basement membrane and are responsible for maintaining epithelial homeostasis under intact conditions, whereas the latter exhibit the capacity to facilitate epithelial regeneration after injury. These two pools of cells can convert into each other, maintaining their quantitative balance. In terms of the active intestinal stem cells, their development into functional epithelium is precisely controlled by the following signaling pathways: Wnt/β-catenin, Ras/Raf/Mek/Erk/MAPK, Notch and BMP/Smad. However, mutations in some of the key regulator genes associated with these signaling pathways, such as APC, Kras and Smad4, are also highly associated with gut malformations. At this point, clarifying the biological characteristics of intestinal stem cells will increase the feasibility of preventing or treating some intestinal diseases, such as colorectal cancer. Moreover, as preclinical data demonstrate the therapeutic effects of colon stem cells on murine models of experimental colitis, the prospects of stem cell-based regenerative treatments for ulcerous lesions in the gastrointestinal tract will be improved all the same. PMID:27610020

  12. Stem cell applications in military medicine.

    PubMed

    Christopherson, Gregory T; Nesti, Leon J

    2011-01-01

    There are many similarities between health issues affecting military and civilian patient populations, with the exception of the relatively small but vital segment of active soldiers who experience high-energy blast injuries during combat. A rising incidence of major injuries from explosive devices in recent campaigns has further complicated treatment and recovery, highlighting the need for tissue regenerative options and intensifying interest in the possible role of stem cells for military medicine. In this review we outline the array of tissue-specific injuries typically seen in modern combat - as well as address a few complications unique to soldiers--and discuss the state of current stem cell research in addressing each area. Embryonic, induced-pluripotent and adult stem cell sources are defined, along with advantages and disadvantages unique to each cell type. More detailed stem cell sources are described in the context of each tissue of interest, including neural, cardiopulmonary, musculoskeletal and sensory tissues, with brief discussion of their potential role in regenerative medicine moving forward. Additional commentary is given to military stem cell applications aside from regenerative medicine, such as blood pharming, immunomodulation and drug screening, with an overview of stem cell banking and the unique opportunity provided by the military and civilian overlap of stem cell research. PMID:22011454

  13. Current understanding concerning intestinal stem cells.

    PubMed

    Cui, Shuang; Chang, Peng-Yu

    2016-08-21

    In mammals, the intestinal epithelium is a tissue that contains two distinct pools of stem cells: active intestinal stem cells and reserve intestinal stem cells. The former are located in the crypt basement membrane and are responsible for maintaining epithelial homeostasis under intact conditions, whereas the latter exhibit the capacity to facilitate epithelial regeneration after injury. These two pools of cells can convert into each other, maintaining their quantitative balance. In terms of the active intestinal stem cells, their development into functional epithelium is precisely controlled by the following signaling pathways: Wnt/β-catenin, Ras/Raf/Mek/Erk/MAPK, Notch and BMP/Smad. However, mutations in some of the key regulator genes associated with these signaling pathways, such as APC, Kras and Smad4, are also highly associated with gut malformations. At this point, clarifying the biological characteristics of intestinal stem cells will increase the feasibility of preventing or treating some intestinal diseases, such as colorectal cancer. Moreover, as preclinical data demonstrate the therapeutic effects of colon stem cells on murine models of experimental colitis, the prospects of stem cell-based regenerative treatments for ulcerous lesions in the gastrointestinal tract will be improved all the same. PMID:27610020

  14. Stem cell tracking using iron oxide nanoparticles.

    PubMed

    Bull, Elizabeth; Madani, Seyed Yazdan; Sheth, Roosey; Seifalian, Amelia; Green, Mark; Seifalian, Alexander M

    2014-01-01

    Superparamagnetic iron oxide nanoparticles (SPIONs) are an exciting advancement in the field of nanotechnology. They expand the possibilities of noninvasive analysis and have many useful properties, making them potential candidates for numerous novel applications. Notably, they have been shown that they can be tracked by magnetic resonance imaging (MRI) and are capable of conjugation with various cell types, including stem cells. In-depth research has been undertaken to establish these benefits, so that a deeper level of understanding of stem cell migratory pathways and differentiation, tumor migration, and improved drug delivery can be achieved. Stem cells have the ability to treat and cure many debilitating diseases with limited side effects, but a main problem that arises is in the noninvasive tracking and analysis of these stem cells. Recently, researchers have acknowledged the use of SPIONs for this purpose and have set out to establish suitable protocols for coating and attachment, so as to bring MRI tracking of SPION-labeled stem cells into common practice. This review paper explains the manner in which SPIONs are produced, conjugated, and tracked using MRI, as well as a discussion on their limitations. A concise summary of recently researched magnetic particle coatings is provided, and the effects of SPIONs on stem cells are evaluated, while animal and human studies investigating the role of SPIONs in stem cell tracking will be explored.

  15. Stem cells: public policy and ethics.

    PubMed

    Towns, Cindy R; Jones, D Gareth

    2004-02-01

    Debate on the regulation of human stem cells needs to bring together scientific, ethical and policy considerations if it is to be adequately informed. Scientific issues of importance include the relevance of the environment in appreciating the extent of stem cell plasticity, and the relative potential of embryonic and adult stem cells to produce other cell types. An awareness that blastocysts (early embryos) and stem cells in the laboratory are pluripotential and not totipotential has implications for ethical and policy debate. The regulations on stem cell research are reviewed, showing that four positions have emerged. Position A corresponds to the prohibition of all embryo research, position B confines the use of embryonic stem cells to those currently in existence and therefore extracted prior to some specified date, position C allows for the use and ongoing isolation of embryonic stem cells from surplus in vitro fertilization embryos, and position D approves of the creation of human embryos specifically for research. Position B which has been adopted by the United States, Germany, and Australia (with subtle differences between them) and which is regarded as a compromise position, is critiqued. This is principally on the basis that, in spite of claims made about it, the ongoing destruction of human embryos will continue. This is because these countries allow in vitro fertilization programs, inherent within which is embryo destruction. It is argued that position C would be a more consistent ethical position for these countries. The possibility of moving to position D is also raised.

  16. Stem cell applications in military medicine

    PubMed Central

    2011-01-01

    There are many similarities between health issues affecting military and civilian patient populations, with the exception of the relatively small but vital segment of active soldiers who experience high-energy blast injuries during combat. A rising incidence of major injuries from explosive devices in recent campaigns has further complicated treatment and recovery, highlighting the need for tissue regenerative options and intensifying interest in the possible role of stem cells for military medicine. In this review we outline the array of tissue-specific injuries typically seen in modern combat - as well as address a few complications unique to soldiers - and discuss the state of current stem cell research in addressing each area. Embryonic, induced-pluripotent and adult stem cell sources are defined, along with advantages and disadvantages unique to each cell type. More detailed stem cell sources are described in the context of each tissue of interest, including neural, cardiopulmonary, musculoskeletal and sensory tissues, with brief discussion of their potential role in regenerative medicine moving forward. Additional commentary is given to military stem cell applications aside from regenerative medicine, such as blood pharming, immunomodulation and drug screening, with an overview of stem cell banking and the unique opportunity provided by the military and civilian overlap of stem cell research. PMID:22011454

  17. Cell migration in the normal and pathological postnatal mammalian brain

    PubMed Central

    Canoll, Peter; Goldman, James E.

    2009-01-01

    In the developing brain, cell migration is a crucial process for structural organization, and is therefore highly regulated to allow the correct formation of complex networks, wiring neurons, and glia. In the early postnatal brain, late developmental processes such as the production and migration of astrocyte and oligodendrocyte progenitors still occur. Although the brain is completely formed and structured few weeks after birth, it maintains a degree of plasticity throughout life, including axonal remodeling, synaptogenesis, but also neural cell birth, migration and integration. The subventricular zone (SVZ) and the dentate gyrus of the hippocampus (DG) are the two main neurogenic niches in the adult brain. Neural stem cells reside in these structures and produce progenitors that migrate toward their ultimate location: the olfactory bulb and granular cell layer of the DG respectively. The aim of this review is to synthesize the increasing information concerning the organization, regulation and function of cell migration in a mature brain. In a normal brain, protein involved in cell-cell or cell-matrix interactions together with secreted proteins acting as chemoattractant or chemorepellant play key roles in the regulation of neural progenitor cell migration. In addition, recent data suggest that gliomas arise from the transformation of neural stem cells or progenitor cells and that glioma cell infiltration recapitulates key aspects of glial progenitor migration. Thus, we will consider glioma migration in the context of progenitor migration. Finally, many observations show that brain lesions and neurological diseases trigger neural stem/progenitor cell activation and migration towards altered structures. The factors involved in such cell migration/recruitment are just beginning to be understood. Inflammation which has long been considered as thoroughly disastrous for brain repair is now known to produce some positive effects on stem/progenitor cell recruitment via

  18. Lifespan Extension and Sustained Expression of Stem Cell Phenotype of Human Breast Epithelial Stem Cells in a Medium with Antioxidants

    PubMed Central

    Wang, Kai-Hung; Kao, An-Pei; Chang, Chia-Cheng; Lin, Ta-Chin

    2016-01-01

    We have previously reported the isolation and culture of a human breast epithelial cell type with stem cell characteristics (Type I HBEC) from reduction mammoplasty using the MSU-1 medium. Subsequently, we have developed several different normal human adult stem cell types from different tissues using the K-NAC medium. In this study, we determined whether this low calcium K-NAC medium with antioxidants (N-acetyl-L-cysteine and L-ascorbic acid-2-phosphate) is a better medium to grow human breast epithelial cells. The results clearly show that the K-NAC medium is a superior medium for prolonged growth (cumulative population doubling levels ranged from 30 to 40) of normal breast epithelial cells that expressed stem cell phenotypes. The characteristics of these mammary stem cells include deficiency in gap junctional intercellular communication, expression of Oct-4, and the ability to differentiate into basal epithelial cells and to form organoid showing mammary ductal and terminal end bud-like structures. Thus, this new method of growing Type I HBECs will be very useful in future studies of mammary development, breast carcinogenesis, chemoprevention, and cancer therapy. PMID:27807451

  19. Stem cells as promising therapeutic options for neurological disorders.

    PubMed

    Yoo, Jongman; Kim, Han-Soo; Hwang, Dong-Youn

    2013-04-01

    Due to the limitations of pharmacological and other current therapeutic strategies, stem cell therapies have emerged as promising options for treating many incurable neurologic diseases. A variety of stem cells including pluripotent stem cells (i.e., embryonic stem cells and induced pluripotent stem cells) and multipotent adult stem cells (i.e., fetal brain tissue, neural stem cells, and mesenchymal stem cells from various sources) have been explored as therapeutic options for treating many neurologic diseases, and it is becoming obvious that each type of stem cell has pros and cons as a source for cell therapy. Wise selection of stem cells with regard to the nature and status of neurologic dysfunctions is required to achieve optimal therapeutic efficacy. To this aim, the stem cell-mediated therapeutic efforts on four major neurological diseases, Parkinson's disease, Huntington's disease, amyotrophic lateral sclerosis, and stroke, will be introduced, and current problems and future directions will be discussed.

  20. 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.

  1. Expression of Stem Cell Markers in Preinvasive Tubal Lesions of Ovarian Carcinoma

    PubMed Central

    Chene, G.; Ouellet, V.; Rahimi, K.; Barres, V.; Meunier, L.; De Ladurantaye, M.; Provencher, D.; Mes-Masson, A. M.

    2015-01-01

    In order to better understand the ovarian serous carcinogenic process with tubal origin, we investigated the expression of stem cell markers in premalignant tubal lesions (serous tubal intraepithelial carcinoma or STIC). We found an increased stem cell marker density in the normal fallopian tube followed by a high CD117 and a low ALDH and CD44 expression in STICs raising the question of the role of the stem cell markers in the serous carcinogenic process. PMID:26504831

  2. Immunological characteristics of mesenchymal stem cells

    PubMed Central

    Machado, Cíntia de Vasconcellos; Telles, Paloma Dias da Silva; Nascimento, Ivana Lucia Oliveira

    2013-01-01

    Although bone marrow is the main source, mesenchymal stem cells have already been isolated from various other tissues, such as the liver, pancreas, adipose tissue, peripheral blood and dental pulp. These plastic adherent cells are morphologically similar to fibroblasts and have a high proliferative potential. This special group of cells possesses two essential characteristics: self-renewal and differentiation, with appropriate stimuli, into various cell types. Mesenchymal stem cells are considered immunologically privileged, since they do not express costimulatory molecules, required for complete T cell activation, on their surface. Several studies have shown that these cells exert an immunosuppressive effect on cells from both innate and acquired immunity systems. Mesenchymal stem cells can regulate the immune response in vitro by inhibiting the maturation of dendritic cells, as well as by suppressing the proliferation and function of T and B lymphocytes and natural killer cells. These special properties of mesenchymal stem cells make them a promising strategy in the treatment of immune mediated disorders, such as graft-versus-host disease and autoimmune diseases, as well as in regenerative medicine. The understanding of immune regulation mechanisms of mesenchymal stem cells, and also those involved in the differentiation of these cells in various lineages is primordial for their successful and safe application in different areas of medicine. PMID:23580887

  3. [Stem cells in cardiological clinical trials].

    PubMed

    Przybycień, Krzysztof; Kornacewicz Jach, Zdzisława; Machaliński, Bogusław

    2011-01-01

    Stem cell-based therapy is a novel therapeutic strategy introduced into cardiology, although there are not any established standards within the stem/progenitor cell type employed, their preparation, rout of administration as well as methods controlling the pathophysiological and clinical parameters after the cell application. The aim of the present work was a complex meta-analysis of the clinical trials carried out in this field. Over 1000 patients with myocardial infarction as well as circulatory failure have been treated with stem cell-based therapy so far, but the obtained results are not concordant. Progress within cell biology and biotechnology give hopes for development of more effective therapeutic approaches. Identification and isolation of cardiac- -specific stem/progenitor cells may deliver new perspectives for such therapy in the nearest future.

  4. Seeing Stem Cells at Work In Vivo

    PubMed Central

    Srivastava, Amit K.; Bulte, Jeff W. M.

    2013-01-01

    Stem cell based-therapies are novel therapeutic strategies that hold key for developing new treatments for diseases conditions with very few or no cures. Although there has been an increase in the number of clinical trials involving stem cell-based therapies in the last few years, the long-term risks and benefits of these therapies are still unknown. Detailed in vivo studies are needed to monitor the fate of transplanted cells, including their distribution, differentiation, and longevity over time. Advancements in non-invasive cellular imaging techniques to track engrafted cells in real-time present a powerful tool for determining the efficacy of stem cell-based therapies. In this review, we describe the latest approaches to stem cell labeling and tracking using different imaging modalities. PMID:23975604

  5. Technology Advancement for Integrative Stem Cell Analyses

    PubMed Central

    Jeong, Yoon

    2014-01-01

    Scientists have endeavored to use stem cells for a variety of applications ranging from basic science research to translational medicine. Population-based characterization of such stem cells, while providing an important foundation to further development, often disregard the heterogeneity inherent among individual constituents within a given population. The population-based analysis and characterization of stem cells and the problems associated with such a blanket approach only underscore the need for the development of new analytical technology. In this article, we review current stem cell analytical technologies, along with the advantages and disadvantages of each, followed by applications of these technologies in the field of stem cells. Furthermore, while recent advances in micro/nano technology have led to a growth in the stem cell analytical field, underlying architectural concepts allow only for a vertical analytical approach, in which different desirable parameters are obtained from multiple individual experiments and there are many technical challenges that limit vertically integrated analytical tools. Therefore, we propose—by introducing a concept of vertical and horizontal approach—that there is the need of adequate methods to the integration of information, such that multiple descriptive parameters from a stem cell can be obtained from a single experiment. PMID:24874188

  6. Analytical strategies for studying stem cell metabolism

    PubMed Central

    Arnold, James M.; Choi, William T.; Sreekumar, Arun

    2015-01-01

    Owing to their capacity for self-renewal and pluripotency, stem cells possess untold potential for revolutionizing the field of regenerative medicine through the development of novel therapeutic strategies for treating cancer, diabetes, cardiovascular and neurodegenerative diseases. Central to developing these strategies is improving our understanding of biological mechanisms responsible for governing stem cell fate and self-renewal. Increasing attention is being given to the significance of metabolism, through the production of energy and generation of small molecules, as a critical regulator of stem cell functioning. Rapid advances in the field of metabolomics now allow for in-depth profiling of stem cells both in vitro and in vivo, providing a systems perspective on key metabolic and molecular pathways which influence stem cell biology. Understanding the analytical platforms and techniques that are currently used to study stem cell metabolomics, as well as how new insights can be derived from this knowledge, will accelerate new research in the field and improve future efforts to expand our understanding of the interplay between metabolism and stem cell biology. PMID:26213533

  7. Time to Reconsider Stem Cell Induction Strategies

    PubMed Central

    Denker, Hans-Werner

    2012-01-01

    Recent developments in stem cell research suggest that it may be time to reconsider the current focus of stem cell induction strategies. During the previous five years, approximately, the induction of pluripotency in somatic cells, i.e., the generation of so-called ‘induced pluripotent stem cells’ (iPSCs), has become the focus of ongoing research in many stem cell laboratories, because this technology promises to overcome limitations (both technical and ethical) seen in the production and use of embryonic stem cells (ESCs). A rapidly increasing number of publications suggest, however, that it is now possible to choose instead other, alternative ways of generating stem and progenitor cells bypassing pluripotency. These new strategies may offer important advantages with respect to ethics, as well as to safety considerations. The present communication discusses why these strategies may provide possibilities for an escape from the dilemma presented by pluripotent stem cells (self-organization potential, cloning by tetraploid complementation, patenting problems and tumor formation risk). PMID:24710555

  8. Technology advancement for integrative stem cell analyses.

    PubMed

    Jeong, Yoon; Choi, Jonghoon; Lee, Kwan Hyi

    2014-12-01

    Scientists have endeavored to use stem cells for a variety of applications ranging from basic science research to translational medicine. Population-based characterization of such stem cells, while providing an important foundation to further development, often disregard the heterogeneity inherent among individual constituents within a given population. The population-based analysis and characterization of stem cells and the problems associated with such a blanket approach only underscore the need for the development of new analytical technology. In this article, we review current stem cell analytical technologies, along with the advantages and disadvantages of each, followed by applications of these technologies in the field of stem cells. Furthermore, while recent advances in micro/nano technology have led to a growth in the stem cell analytical field, underlying architectural concepts allow only for a vertical analytical approach, in which different desirable parameters are obtained from multiple individual experiments and there are many technical challenges that limit vertically integrated analytical tools. Therefore, we propose--by introducing a concept of vertical and horizontal approach--that there is the need of adequate methods to the integration of information, such that multiple descriptive parameters from a stem cell can be obtained from a single experiment.

  9. Stem cell bioprocessing: fundamentals and principles

    PubMed Central

    Placzek, Mark R.; Chung, I-Ming; Macedo, Hugo M.; Ismail, Siti; Mortera Blanco, Teresa; Lim, Mayasari; Min Cha, Jae; Fauzi, Iliana; Kang, Yunyi; Yeo, David C.L.; Yip Joan Ma, Chi; Polak, Julia M.; Panoskaltsis, Nicki; Mantalaris, Athanasios

    2008-01-01

    In recent years, the potential of stem cell research for tissue engineering-based therapies and regenerative medicine clinical applications has become well established. In 2006, Chung pioneered the first entire organ transplant using adult stem cells and a scaffold for clinical evaluation. With this a new milestone was achieved, with seven patients with myelomeningocele receiving stem cell-derived bladder transplants resulting in substantial improvements in their quality of life. While a bladder is a relatively simple organ, the breakthrough highlights the incredible benefits that can be gained from the cross-disciplinary nature of tissue engineering and regenerative medicine (TERM) that encompasses stem cell research and stem cell bioprocessing. Unquestionably, the development of bioprocess technologies for the transfer of the current laboratory-based practice of stem cell tissue culture to the clinic as therapeutics necessitates the application of engineering principles and practices to achieve control, reproducibility, automation, validation and safety of the process and the product. The successful translation will require contributions from fundamental research (from developmental biology to the ‘omics’ technologies and advances in immunology) and from existing industrial practice (biologics), especially on automation, quality assurance and regulation. The timely development, integration and execution of various components will be critical—failures of the past (such as in the commercialization of skin equivalents) on marketing, pricing, production and advertising should not be repeated. This review aims to address the principles required for successful stem cell bioprocessing so that they can be applied deftly to clinical applications. PMID:19033137

  10. 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

  11. Stem cell bioprocessing: fundamentals and principles.

    PubMed

    Placzek, Mark R; Chung, I-Ming; Macedo, Hugo M; Ismail, Siti; Mortera Blanco, Teresa; Lim, Mayasari; Cha, Jae Min; Fauzi, Iliana; Kang, Yunyi; Yeo, David C L; Ma, Chi Yip Joan; Polak, Julia M; Panoskaltsis, Nicki; Mantalaris, Athanasios

    2009-03-01

    In recent years, the potential of stem cell research for tissue engineering-based therapies and regenerative medicine clinical applications has become well established. In 2006, Chung pioneered the first entire organ transplant using adult stem cells and a scaffold for clinical evaluation. With this a new milestone was achieved, with seven patients with myelomeningocele receiving stem cell-derived bladder transplants resulting in substantial improvements in their quality of life. While a bladder is a relatively simple organ, the breakthrough highlights the incredible benefits that can be gained from the cross-disciplinary nature of tissue engineering and regenerative medicine (TERM) that encompasses stem cell research and stem cell bioprocessing. Unquestionably, the development of bioprocess technologies for the transfer of the current laboratory-based practice of stem cell tissue culture to the clinic as therapeutics necessitates the application of engineering principles and practices to achieve control, reproducibility, automation, validation and safety of the process and the product. The successful translation will require contributions from fundamental research (from developmental biology to the 'omics' technologies and advances in immunology) and from existing industrial practice (biologics), especially on automation, quality assurance and regulation. The timely development, integration and execution of various components will be critical-failures of the past (such as in the commercialization of skin equivalents) on marketing, pricing, production and advertising should not be repeated. This review aims to address the principles required for successful stem cell bioprocessing so that they can be applied deftly to clinical applications.

  12. Hematopoietic stem cell mobilization: updated conceptual renditions

    PubMed Central

    Bonig, H; Papayannopoulou, T

    2013-01-01

    Despite its specific clinical relevance, the field of hematopoietic stem cell mobilization has received broad attention, owing mainly to the belief that pharmacologic stem cell mobilization might provide clues as to how stem cells are retained in their natural environment, the bone marrow ‘niche’. Inherent to this knowledge is also the desire to optimally engineer stem cells to interact with their target niche (such as after transplantation), or to lure malignant stem cells out of their protective niches (in order to kill them), and in general to decipher the niche’s structural components and its organization. Whereas, with the exception of the recent addition of CXCR4 antagonists to the armamentarium for mobilization of patients refractory to granulocyte colony-stimulating factor alone, clinical stem cell mobilization has not changed significantly over the last decade or so, much effort has been made trying to explain the complex mechanism(s) by which hematopoietic stem and progenitor cells leave the marrow. This brief review will report some of the more recent advances about mobilization, with an attempt to reconcile some of the seemingly inconsistent data in mobilization and to interject some commonalities among different mobilization regimes. PMID:22951944

  13. Cancer stem cells, cancer cell plasticity and radiation therapy.

    PubMed

    Vlashi, Erina; Pajonk, Frank

    2015-04-01

    Since the first prospective identification of cancer stem cells in solid cancers the cancer stem cell hypothesis has reemerged as a research topic of increasing interest. It postulates that solid cancers are organized hierarchically with a small number of cancer stem cells driving tumor growth, repopulation after injury and metastasis. They give rise to differentiated progeny, which lack these features. The model predicts that for any therapy to provide cure, all cancer stem cells have to be eliminated while the survival of differentiated progeny is less critical. In this review we discuss recent reports challenging the idea of a unidirectional differentiation of cancer cells. These reports provide evidence supporting the idea that non-stem cancer cells exhibit a remarkable degree of plasticity that allows them to re-acquire cancer stem cell traits, especially in the context of radiation therapy. We summarize conditions under which differentiation is reversed and discuss the current knowledge of the underlying mechanisms.

  14. Cancer Stem Cells, Cancer Cell Plasticity and Radiation Therapy

    PubMed Central

    Vlashi, Erina; Pajonk, Frank

    2014-01-01

    Summary Since the first prospective identification of cancer stem cells in solid cancers the cancer stem cell hypothesis has reemerged as a research topic of increasing interest. It postulates that solid cancers are organized hierarchically with a small number of cancer stem cells driving tumor growth, repopulation after injury and metastasis. They give rise to differentiated progeny, which lack these features. The model predicts that for any therapy to provide cure, all cancer stem cells have to be eliminated while the survival of differentiated progeny is less critical. In this review we discuss recent reports challenging the idea of a unidirectional differentiation of cancer cells. These reports provide evidence supporting the idea that non-stem cancer cells exhibit a remarkable degree of plasticity that allows them to re-acquire cancer stem cell traits, especially in the context of radiation therapy. We summarize conditions under which differentiation is reversed and discuss the current knowledge of the underlying mechanisms. PMID:25025713

  15. TOPICAL REVIEW: Stem cells engineering for cell-based therapy

    NASA Astrophysics Data System (ADS)

    Taupin, Philippe

    2007-09-01

    Stem cells carry the promise to cure a broad range of diseases and injuries, from diabetes, heart and muscular diseases, to neurological diseases, disorders and injuries. Significant progresses have been made in stem cell research over the past decade; the derivation of embryonic stem cells (ESCs) from human tissues, the development of cloning technology by somatic cell nuclear transfer (SCNT) and the confirmation that neurogenesis occurs in the adult mammalian brain and that neural stem cells (NSCs) reside in the adult central nervous system (CNS), including that of humans. Despite these advances, there may be decades before stem cell research will translate into therapy. Stem cell research is also subject to ethical and political debates, controversies and legislation, which slow its progress. Cell engineering has proven successful in bringing genetic research to therapy. In this review, I will review, in two examples, how investigators are applying cell engineering to stem cell biology to circumvent stem cells' ethical and political constraints and bolster stem cell research and therapy.

  16. Germline stem cells: origin and destiny.

    PubMed

    Lehmann, Ruth

    2012-06-14

    Germline stem cells are key to genome transmission to future generations. Over recent years, there have been numerous insights into the regulatory mechanisms that govern both germ cell specification and the maintenance of the germline in adults. Complex regulatory interactions with both the niche and the environment modulate germline stem cell function. This perspective highlights some examples of this regulation to illustrate the diversity and complexity of the mechanisms involved.

  17. Telomeres, stem cells, senescence, and cancer

    PubMed Central

    Sharpless, Norman E.; DePinho, Ronald A.

    2004-01-01

    Mammalian aging occurs in part because of a decline in the restorative capacity of tissue stem cells. These self-renewing cells are rendered malignant by a small number of oncogenic mutations, and overlapping tumor suppressor mechanisms (e.g., p16INK4a-Rb, ARF-p53, and the telomere) have evolved to ward against this possibility. These beneficial antitumor pathways, however, appear also to limit the stem cell life span, thereby contributing to aging. PMID:14722605

  18. Defining Molecular Phenotypes of Mesenchymal and hematopoietic Stem Cells derived from Peripheral blood of Acute Lymphocytic Leukemia patients for regenerative stem cell therapy.

    PubMed

    Potdar, Pd; Subedi, Rp

    2011-01-01

    Acute Lymphocytic Leukemia (ALL) is a clonal myeloid disorder affecting all age groups, characterized by accumulation of immature blast cells in bone marrow and in peripheral blood. Autologous Bone Marrow Transplantation is a present treatment for cure of ALL patients, which is very expensive, invasive process and may have possibility of transplantation of malignant stem cells to patients. In the present study, we hypothesized to isolate large number of normal Mesenchymal & Hematopoietic stem cells from peripheral blood of ALL patients, which will be further characterized for their normal phenotypes by using specific molecular stem cell markers. This is the first study, which defines the existing phenotypes of isolated MSCs and HSCs from peripheral blood of ALL patients. We have established three cell lines in which two were Mesenchymal stem cells designated as MSCALL and MSCnsALL and one was suspension cell line designated as HSCALL. The HSCALL cell line was developed from the lymphocyte like cells secreted by MSCALL cells. Our study also showed that MSCALL from peripheral blood of ALL patient secreted hematopoietic stem cells in vitro culture. We have characterized all three-cell lines by 14 specific stem cell molecular markers. It was found that both MSC cell lines expressed CD105, CD13, and CD73 with mixed expression of CD34 and CD45 at early passage whereas, HSCALL cell line expressed prominent feature of hematopoietic stem cells such as CD34 and CD45 with mild expression of CD105 and CD13. All three-cell lines expressed LIF, OCT4, NANOG, SOX2, IL6, and DAPK. These cells mildly expressed COX2 and did not express BCR-ABL. Overall it was shown that isolated MSCs and HSCs can be use as a model system to study the mechanism of leukemia at stem cell level and their use in stem cell regeneration therapy for Acute Lymphocytic Leukemia.

  19. Matrix regulators in neural stem cells functions

    PubMed Central

    Wade, Anna; McKinney, Andrew; Phillips, Joanna J.

    2014-01-01

    Background Neural stem/progenitor cells (NSPCs) reside within a complex and dynamic extracellular microenvironment, or niche. This niche regulates fundamental aspects of their behavior during normal neural development and repair. Precise yet dynamic regulation of NSPC self-renewal, migration, and differentiation is critical and must persist over the life of an organism. Scope of Review In this review, we summarize some of the major components of the NSPC niche and provide examples of how cues from the extracellular matrix regulate NSPC behaviors. We use proteoglycans to illustrate the many diverse roles of the niche in providing temporal and spatial regulation of cellular behavior. Major Conclusions The NSPC niche is comprised of multiple components that include; soluble ligands, such as growth factors, morphogens, chemokines, and neurotransmitters, the extracellular matrix, and cellular components. As illustrated by proteoglycans, a major component of the extracellular matrix, the NSPC niche provides temporal and spatial regulation of NSPC behaviors. General Significance The factors that control NSPC behavior are vital to understand as we attempt to modulate normal neural development and repair. Furthermore, an improved understanding of how these factors regulate cell proliferation, migration, and differentiation, crucial for malignancy, may reveal novel anti-tumor strategies. PMID:24447567

  20. MicroRNAs: key regulators of stem cells.

    PubMed

    Gangaraju, Vamsi K; Lin, Haifan

    2009-02-01

    The hallmark of a stem cell is its ability to self-renew and to produce numerous differentiated cells. This unique property is controlled by dynamic interplays between extrinsic signalling, epigenetic, transcriptional and post-transcriptional regulations. Recent research indicates that microRNAs (miRNAs) have an important role in regulating stem cell self-renewal and differentiation by repressing the translation of selected mRNAs in stem cells and differentiating daughter cells. Such a role has been shown in embryonic stem cells, germline stem cells and various somatic tissue stem cells. These findings reveal a new dimension of gene regulation in controlling stem cell fate and behaviour. PMID:19165214

  1. Metastatic cancer stem cells: new molecular targets for cancer therapy.

    PubMed

    Leirós, G J; Balañá, M E

    2011-11-01

    The cancer stem cell (CSC) hypothesis, predicts that a small subpopulation of cancer cells that possess "stem-like" characteristics, are responsible for initiating and maintaining cancer growth. According to the CSC model the many cell populations found in a tumour might represent diverse stages of differentiation. From the cellular point of view metastasis is considered a highly inefficient process and only a subset of tumour cells is capable of successfully traversing the entire metastatic cascade and eventually re-initiates tumour growth at distant sites. Some similar features of both normal and malignant stem cells suggest that CSCs are not only responsible for tumorigenesis, but also for metastases. The CSC theory proposes that the ability of a tumour to metastasize is an inherent property of a subset of CSCs. The similar biological characteristics shared by normal stem cells (NSCs) and CSCs mainly implicate self-renewal and differentiation potential, survival ability, niche-specific microenvironment requirements and specific homing to metastatic sites and may have important implications in terms of new approaches to cancer therapy in the metastatic setting. There are several agents targeting many of these CSC features that have shown to be effective both in vitro and in vivo. Although clinical trials results are still preliminary and continue under investigation, these new therapies are very promising. The identification of new therapeutic targets and drugs based on CSC model constitutes a great challenge. PMID:21470128

  2. Metastatic cancer stem cells: new molecular targets for cancer therapy.

    PubMed

    Leirós, G J; Balañá, M E

    2011-11-01

    The cancer stem cell (CSC) hypothesis, predicts that a small subpopulation of cancer cells that possess "stem-like" characteristics, are responsible for initiating and maintaining cancer growth. According to the CSC model the many cell populations found in a tumour might represent diverse stages of differentiation. From the cellular point of view metastasis is considered a highly inefficient process and only a subset of tumour cells is capable of successfully traversing the entire metastatic cascade and eventually re-initiates tumour growth at distant sites. Some similar features of both normal and malignant stem cells suggest that CSCs are not only responsible for tumorigenesis, but also for metastases. The CSC theory proposes that the ability of a tumour to metastasize is an inherent property of a subset of CSCs. The similar biological characteristics shared by normal stem cells (NSCs) and CSCs mainly implicate self-renewal and differentiation potential, survival ability, niche-specific microenvironment requirements and specific homing to metastatic sites and may have important implications in terms of new approaches to cancer therapy in the metastatic setting. There are several agents targeting many of these CSC features that have shown to be effective both in vitro and in vivo. Although clinical trials results are still preliminary and continue under investigation, these new therapies are very promising. The identification of new therapeutic targets and drugs based on CSC model constitutes a great challenge.

  3. Centre for human development, stem cells & regeneration.

    PubMed

    Oreffo, Richard O C

    2014-01-01

    The Centre for Human Development, Stem Cells and Regeneration (CHDSCR) was founded in 2004 as a cross-disciplinary research and translational program within the Faculty of Medicine at the University of Southampton. The Centre undertakes fundamental research into early development and stem cells together with applied translational research for patient benefit. The Centre has vibrant and thriving multidisciplinary research programs that harness the translational strength of the Faculty together with an innovative Stem Cell PhD program, outstanding clinical infrastructure and enterprise to deliver on this vision.

  4. Autologous Stem Cell Mobilization and Collection.

    PubMed

    Hsu, Yen-Michael S; Cushing, Melissa M

    2016-06-01

    Peripheral blood stem cell collection is an effective approach to obtain a hematopoietic graft for stem cell transplantation. Developing hematopoietic stem/progenitor cell (HSPC) mobilization methods and collection algorithms have improved efficiency, clinical outcomes, and cost effectiveness. Differences in mobilization mechanisms may change the HSPC content harvested and result in different engraftment kinetics and complications. Patient-specific factors can affect mobilization. Incorporating these factors in collection algorithms and improving assays for evaluating mobilization further extend the ability to obtain sufficient HSPCs for hematopoietic repopulation. Technological advance and innovations in leukapheresis have improved collection efficiency and reduced adverse effects. PMID:27112997

  5. Stem cell therapy in oral and maxillofacial region: An overview

    PubMed Central

    Sunil, PM; Manikandhan, R; Muthu, MS; Abraham, S

    2012-01-01

    Cells with unique capacity for self-renewal and potency are called stem cells. With appropriate biochemical signals stem cells can be transformed into desirable cells. The idea behind this article is to shortly review the obtained literature on stem cell with respect to their properties, types and advantages of dental stem cells. Emphasis has been given to the possibilities of stem cell therapy in the oral and maxillofacial region including regeneration of tooth and craniofacial defects. PMID:22434942

  6. Leukemia cell microvesicles promote survival in umbilical cord blood hematopoietic stem cells

    PubMed Central

    Razmkhah, Farnaz; Soleimani, Masoud; Mehrabani, Davood; Karimi, Mohammad Hossein; Kafi-abad, Sedigheh Amini

    2015-01-01

    Microvesicles can transfer their contents, proteins and RNA, to target cells and thereby transform them. This may induce apoptosis or survival depending on cell origin and the target cell. In this study, we investigate the effect of leukemic cell microvesicles on umbilical cord blood hematopoietic stem cells to seek evidence of apoptosis or cell survival. Microvesicles were isolated from both healthy donor bone marrow samples and Jurkat cells by ultra-centrifugation and were added to hematopoietic stem cells sorted from umbilical cord blood samples by magnetic associated cell sorting (MACS) technique. After 7 days, cell count, cell viability, flow cytometry analysis for hematopoietic stem cell markers and qPCR for P53 gene expression were performed. The results showed higher cell number, higher cell viability rate and lower P53 gene expression in leukemia group in comparison with normal and control groups. Also, CD34 expression as the most important hematopoietic stem cell marker, did not change during the treatment and lineage differentiation was not observed. In conclusion, this study showed anti-apoptotic effect of leukemia cell derived microvesicles on umbilical cord blood hematopoietic stem cells. PMID:26862318

  7. Bioprinting and Differentiation of Stem Cells.

    PubMed

    Irvine, Scott A; Venkatraman, Subbu S

    2016-01-01

    The 3D bioprinting of stem cells directly into scaffolds offers great potential for the development of regenerative therapies; in particular for the fabrication of organ and tissue substitutes. For this to be achieved; the lineage fate of bioprinted stem cell must be controllable. Bioprinting can be neutral; allowing culture conditions to trigger differentiation or alternatively; the technique can be designed to be stimulatory. Such factors as the particular bioprinting technique; bioink polymers; polymer cross-linking mechanism; bioink additives; and mechanical properties are considered. In addition; it is discussed that the stimulation of stem cell differentiation by bioprinting may lead to the remodeling and modification of the scaffold over time matching the concept of 4D bioprinting. The ability to tune bioprinting properties as an approach to fabricate stem cell bearing scaffolds and to also harness the benefits of the cells multipotency is of considerable relevance to the field of biomaterials and bioengineering. PMID:27617991

  8. Cancer Stem Cells: Plasticity Works against Therapy

    PubMed Central

    Vinogradova, T. V.; Chernov, I. P.; Monastyrskaya, G. S.; Kondratyeva, L. G.; Sverdlov, E. D.

    2015-01-01

    Great successes in identification and deciphering of mechanisms of the adult stem cells regulation have given rise to the idea that stem cells can also function in tumors as central elements of their development, starting from the initial stage and continuing until metastasis. Such cells were called cancer stem cells (CSCs). Over the course of intense discussion, the CSCs hypothesis gradually began to be perceived as an obvious fact. Recently, the existence of CSCs has been indeed confirmed in a number of works. However, when are CSCs universal prerequisites of tumors and to what extent their role is essential for tumor evolution remains an issue far from resolved. Likewise, the problem of potential use of CSCs as therapeutic targets remains unsolved. The present review attempts to analyze the issue of cancer stem cells and the potential of targeting them in tumor therapy. PMID:26798491

  9. Stem Cell Research and Health Education.

    PubMed

    Eve, David J; Marty, Phillip J; McDermott, Robert J; Klasko, Stephen K; Sanberg, Paul R

    2008-01-01

    Stem cells are being touted as the greatest discovery for the potential treatment of a myriad of diseases in the new millennium, but there is still much research to be done before it will be known whether they can live up to this description. There is also an ethical debate over the production of one of the most valuable types of stem cell: the embryonic form. Consequently, there is public confusion over the benefits currently being derived from the use of stem cells and what can potentially be expected from their use in the future. The health educator's role is to give an unbiased account of the current state of stem cell research. This paper provides the groundwork by discussing the types of cells currently identified, their potential use, and some of the political and ethical pitfalls resulting from such use.

  10. Translational findings from cardiovascular stem cell research.

    PubMed

    Mazhari, Ramesh; Hare, Joshua M

    2012-01-01

    The possibility of using stem cells to regenerate damaged myocardium has been actively investigated since the late 1990s. Consistent with the traditional view that the heart is a "postmitotic" organ that possesses minimal capacity for self-repair, much of the preclinical and clinical work has focused exclusively on introducing stem cells into the heart, with the hope of differentiation of these cells into functioning cardiomyocytes. This approach is ongoing and retains promise but to date has yielded inconsistent successes. More recently, it has become widely appreciated that the heart possesses endogenous repair mechanisms that, if adequately stimulated, might regenerate damaged cardiac tissue from in situ cardiac