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Sample records for spermatogonial stem-cell population

  1. Propagation of human spermatogonial stem cells in vitro.

    Science.gov (United States)

    Sadri-Ardekani, Hooman; Mizrak, Sefika C; van Daalen, Saskia K M; Korver, Cindy M; Roepers-Gajadien, Hermien L; Koruji, Morteza; Hovingh, Suzanne; de Reijke, Theo M; de la Rosette, Jean J M C H; van der Veen, Fulco; de Rooij, Dirk G; Repping, Sjoerd; van Pelt, Ans M M

    2009-11-18

    Young boys treated with high-dose chemotherapy are often confronted with infertility once they reach adulthood. Cryopreserving testicular tissue before chemotherapy and autotransplantation of spermatogonial stem cells at a later stage could theoretically allow for restoration of fertility. To establish in vitro propagation of human spermatogonial stem cells from small testicular biopsies to obtain an adequate number of cells for successful transplantation. Study performed from April 2007 to July 2009 using testis material donated by 6 adult men who underwent orchidectomy as part of prostate cancer treatment. Testicular cells were isolated and cultured in supplemented StemPro medium; germline stem cell clusters that arose were subcultured on human placental laminin-coated dishes in the same medium. Presence of spermatogonia was determined by reverse transcriptase polymerase chain reaction and immunofluorescence for spermatogonial markers. To test for the presence of functional spermatogonial stem cells in culture, xenotransplantation to testes of immunodeficient mice was performed, and migrated human spermatogonial stem cells after transplantation were detected by COT-1 fluorescence in situ hybridization. The number of colonized spermatogonial stem cells transplanted at early and later points during culture were counted to determine propagation. Propagation of spermatogonial stem cells over time. Testicular cells could be cultured and propagated up to 15 weeks. Germline stem cell clusters arose in the testicular cell cultures from all 6 men and could be subcultured and propagated up to 28 weeks. Expression of spermatogonial markers on both the RNA and protein level was maintained throughout the entire culture period. In 4 of 6 men, xenotransplantation to mice demonstrated the presence of functional spermatogonial stem cells, even after prolonged in vitro culture. Spermatogonial stem cell numbers increased 53-fold within 19 days in the testicular cell culture and

  2. Radiation response of spermatogonial stem cells in the mouse

    International Nuclear Information System (INIS)

    Bootsma, A.L.

    1978-01-01

    Spermatogonial stem cells are able to repopulate the testis by forming clones that elongate along the walls of the seminiferous tubules depleted of spermatogenetic cells as a result of an irradiation. The surviving number of stem cells after irradiation was estimated by determining the fraction of repopulated tubules in cross-sections of the testis 11 weeks after irradiation. This fraction, called the 'repopulation index', is assumed to be directly proportional to the number of surviving stem cells. The response of spermatogonial stem cells in the CBA mouse to 1-MeV fission neutrons was investigated. Radioresistant, colony forming stem cells in the mouse testis move into a much more radiosensitive phase of their cell cycle shortly after irradiation. This is demonstrated in publication II in experiments in which total doses of 300 rad of neutrons and 1200 rad of X-rays were split into two equal fractions. The radiation response of spermatogonial stem cells in the mouse which survived various doses of fission neutrons 24 hours before was studied in publication III. Twenty four hours after a dose of 150 rad of fission neutrons all first-dose survivors have moved from a radioresistant (D 0 89+-4 rad in this study) towards a radiosensitive phase of their cell cycle. Spermatogonial stem cells which survive a neutron dose of 150 rad all belong to a radioresistant stem cell population in the seminiferous epithelium. The data in publication IV show that during the first 26 days after a dose of 150 rad of neutrons the stem cell population first increases and then slowly decreases its radiosensitivity, to stay fixed at a relatively high level. (Auth.)

  3. Spermatogonial stem cells: Progress and prospects

    Directory of Open Access Journals (Sweden)

    Mitsuru Komeya

    2015-01-01

    Full Text Available Twenty years ago, the transplantation of spermatogonial stem cells (SSCs from a mouse to other recipient mice was shown to be feasible, which clearly demonstrated the functional identity of SSCs. Since then, several important new findings and other technical developments have followed, which included a new hypothesis on their cell kinetics and spermatogonial hierarchy in the testis, a culture method allowing their self-renewal and proliferation, a testis tissue organ culture method, which induced their complete differentiation up to sperm, and the in vitro induction of germ cells from embryonic stem cells and induced pluripotent stem cells. These advancements reinforced or advanced our understanding of this unique cell. Nonetheless, there are many unresolved questions in the study of spermatogonial stem cells and a long road remains until these cells can be used clinically in reproductive medicine.

  4. Spermatogonial stem cell renewal following irradiation

    International Nuclear Information System (INIS)

    Fabrikant, J.I.

    1979-05-01

    The spermatogonial cell renewal system can maintain function and a steady level of cell population for relatively long periods of continuous low-level irradiation indicating that there does not appear to be a serious accumulation, over many generations, of damage affecting proliferation. Provided the dose-rate is quite low, there is an effective selective removal of damaged cells with almost complete repair of cellular nonlethal damage. At dose-rates greater than 2 rad/day, spermatogonia are very sensitive to radiation death, and the main reason for the low tolerance to continuous stress could, in part, be the limited extent of compensatory mechanisms regulating spermatogonial cell production. However, there is some capacity to change the patterns of cellular proliferation while still remaining under homeostatic control, and this capacity appears to reside in the relatively radioresistant A/sub s/ stem-cell population. Little is known about the extent to which the spermatogonial cell population can repair nonlethal cellular radiation damage accumulated under continuous stress affecting the regenerative capacity of the tissue. After acute exposure, a minimum number of surviving type A/sub s/ stem-cells are required to repopulate the functional seminiferous epithelium, regeneration proceeds along an ordered cell stage sequence, and is dependent on the time required for all stages from type A/sub s/ spermatogonia to mature spermatozoa. Under continuous irradiation, provided the dose-rate is not too high, the repopulating ability of the seminiferous epithelium is maintained, in the presence of injury, due to initial repair and long-term repair of cellular radiation damage. There is evidence for initial repair, since a dose-rate effect exists in type A survival, at low doses. Long-term repair occurs due to differential radiosensitivities of spermatogonia

  5. Propagation of bovine spermatogonial stem cells in vitro

    NARCIS (Netherlands)

    Aponte, Pedro M.; Soda, Takeshi; Teerds, Katja J.; Mizrak, S. Canan; van de Kant, Henk J. G.; de Rooij, Dirk G.

    2008-01-01

    The access to sufficient numbers of spermatogonial stem cells (SSCs) is a prerequisite for the study of their regulation and further biomanipulation. A specialized medium and several growth factors were tested to study the in vitro behavior of bovine type A spermatogonia, a cell population that

  6. Establishment of cell lines with rat spermatogonial stem cell characteristics

    NARCIS (Netherlands)

    van Pelt, Ans M. M.; Roepers-Gajadien, Hermien L.; Gademan, Iris S.; Creemers, Laura B.; de Rooij, Dirk G.; van Dissel-Emiliani, Federica M. F.

    2002-01-01

    Spermatogonial cell lines were established by transfecting a mixed population of purified rat A(s) (stem cells), A(pr) and A(al) spermatogonia with SV40 large T antigen. Two cell lines were characterized and found to express Hsp90alpha and oct-4, specific markers for germ cells and A spermatogonia,

  7. The radiosensitivity of spermatogonial stem cells in C3H/101 F1 hybrid mice

    International Nuclear Information System (INIS)

    Van der Meer, Yvonne; De Rooij, Dirk G.; Cattanach, Bruce M.

    1993-01-01

    The radiosensitivity of spermatogonial stem cells of C3H/HeHx101/H F 1 hybrid mice was determined by counting undifferentiated spermatogonia at 10 days after X-irradiation. During the spermatogenic cycle, differences in radiosensitivity were found, which were correlated with the proliferative activity of the spermatogonial stem cells. In stage VIII irr , during quiescence, the spermatogonial stem cells were most radiosensitive with a D 0 of 1.4 Gy. In stages XI irr -V irr , when the cells were proliferatively active, the D 0 was about 2.6 Gy. Based on the D 0 values for sensitive and resistant spermatogonia and on the D 0 for the total population, a ratio of 45:55% of sensitive to resistant spermatogonial stem cells was estimated for cell killing. When the present data were compared with data on translocation induction obtained in mice of the same genotype, a close fit was obtained when the translocation yield (Y; in % abnormal cells) after a radiation dose D was described by Y=e τD , with τ=1 for the sensitive and τ=0.1 for the resistant spermatogonial stem cells, with a maximal e τD of 100

  8. Follicle stimulating hormone increases spermatogonial stem cell colonization during in vitro co-culture.

    Science.gov (United States)

    Narenji Sani, Reza; Tajik, Parviz; Yousefi, Mohammad Hassan; Movahedin, Mansoureh; Qasemi-Panahi, Babak; Shafiei, Shiva; Ahmadi Hamedani, Mahmood

    2013-01-01

    The complex process of spermatogenesis is regulated by various factors. Studies on spermatogonial stem cells (SCCs) have provided very important tool to improve herd genetic and different field. 0.2 to 0.3 percent of total cells of seminiferous tubules is consist of spermatogonial stem cells. To investigate and biomanipulation of these cells, proliferation and viability rate of cells should be increased in vitro, at first. Follicle stimulating hormone (FSH) has been suggested to play a determinant role in the survival of germ cells in addition to increasing spermatogonial proliferation. In this study, the in vitro effects of FSH on spermatogonial cell colony formation were investigated. Sertoli and spermatogonial cells were isolated from 3-5 months old calves. The identity of the Sertoli cells and spermatogonial stem cells were confirmed through immunocytochemistry and colony morphology, respectively. Co-cultured Sertoli and spermatogonial cells were treated with FSH in different dose of 10, 20 and 40 IU mL(-1) FSH, before colony assay. Results indicated that, FSH increased in vitro colonization of spermatogonial cells in comparison with control group. In conclusion, using FSH provided proper bovine spermatogonial stem cell culture medium for in vitro study of these cells.

  9. The spermatogonial stem cell niche

    NARCIS (Netherlands)

    de Rooij, Dirk G.

    2009-01-01

    Spermatogonial stem cells (SSCs; A(s) spermatogonia) and their direct descendants (A(pr) and A(al) spermatogonia) are preferentially located in those areas of the seminiferous tubules that border on the interstitial tissue. Fewer of these cells are present in tubule areas directly bordering on

  10. Follicle stimulating hormone increases spermatogonial stem cell colonization during in vitro co - culture

    Directory of Open Access Journals (Sweden)

    Reza Narenji Sani

    2013-03-01

    Full Text Available The complex process of spermatogenesis is regulated by various factors. Studies onspermatogonial stem cells(SCCshave provided very important tool to improve herd geneticand different field. 0.2 to 0.3 percent of total cells of seminiferous tubules is consist ofspermatogonial stem cells. To investigate and biomanipulation of these cells, proliferationand viability rate of cells should be increasedin vitro, at first. Follicle stimulating hormone(FSH has been suggested to play a determinant role in the survival of germ cells in additionto increasing spermatogonial proliferation. In this study, thein vitroeffects ofFSHonspermatogonial cell colony formation were investigated. Sertoli and spermatogonial cellswere isolated from 3-5 months old calves. The identity of theSertoli cells and spermatogonialstem cells were confirmed through immunocytochemistry and colony morphology,respectively. Co-cultured Sertoli and spermatogonial cells were treatedwithFSHin differentdose of10, 20 and 40 IU mL-1FSH, before colony assay.Results indicated that,FSHincreasedin vitrocolonization of spermatogonial cells in comparison with control group. In conclusion,usingFSHprovided proper bovine spermatogonial stem cell culture medium forin vitrostudy of these cells.

  11. Deriving multipotent stem cells from mouse spermatogonial stem cells: a new tool for developmental and clinical research

    NARCIS (Netherlands)

    de Rooij, Dirk G.; Mizrak, S. Canan

    2008-01-01

    In recent years, embryonic stem (ES) cell-like cells have been obtained from cultured mouse spermatogonial stem cells (SSCs). These advances have shown that SSCs can transition from being the stem cell-producing cells of spermatogenesis to being multipotent cells that can differentiate into

  12. Differentiation of Bovine Spermatogonial Stem Cells into Osteoblasts

    OpenAIRE

    Qasemi-Panahi, Babak; Tajik, Parviz; Movahedin, Mansoureh; Moghaddam, Gholamali; Barzgar, Younes; Heidari-Vala, Hamed

    2011-01-01

    Spermatogonial Stem Cell (SSC) technologies provide multiple opportunities for research in the field of biotechnology and regenerative medicine. The therapeutic use of Embryonic Stem Cells (ESCs) is restricted due to severe ethical and immunological concerns. Therefore, we need a new pluripotent cell type. Despite well-known role of germ cells in the gametogenesis, some facts apparently show their multipotentiality. In the present study, bovine SSCs were co-cultured with Sertoli cell for 7 da...

  13. Degeneration and regeneration of the spermatogonial stem-cell system after exposure to ionizing radiation

    International Nuclear Information System (INIS)

    Fabrikant, J.I.

    1979-02-01

    Under continuous low level irradiation at 1.8 rad/day which will permit the survival of at least 10 generations in the mouse, cell renewal during spermatogenesis can achieve a near-steady state of cell population at approx. 80% of control levels for at least 12 cycles of spermatogonial cell renewal and 3 cycles of the seminiferous epithelium. Changes in the patterns of spermatogonial cell population kinetics indicate that there is some limited reserve of proliferative capacity, and the extent to which these changes may be due to decreasing the cell cycle time of a long-cycling type A/sub s/ stem-cell population in the type A cell compartment, or the bringing-in of a potentially proliferative type A/sub s/ population is now more clearly understood. These mechanisms are important in maintaining the steady-state of spermatogonial cell renewal under stress. The autoradiographic data indicate that under low level irradiation there are delays in the flow of the differentiated types A/sub 1-4/, intermediate, and type B spermatogonia in each proliferative subcompartment through the postsynthetic G 2 period into cell division, associated with a decrease in the duration of DNA synthesis, but with relatively normal cell cycle times. Under continuous exposure to low level irradiation, there is a differential radiosensitivity among the differentiated types A 1 to A 4 , In and B cells affecting proliferation - depopulation is minimal but evident in type B and In cells, much less among types A/sub 1-4/ cells and preleptotene spermatocytes, and least in the type A/sub s/ stem-cell compartment

  14. Role for Adhesion Molecules in the Spermatogonial Stem Cell Niche

    NARCIS (Netherlands)

    de Rooij, Dirk G.; Repping, S.; van Pelt, Ans M. M.

    2008-01-01

    In this issue of Cell Stem Cell, Kanatsu-Shinohara et al. (2008) show that beta 1-integrin participates in normal spermatogenesis and is required for spermatogonial stem cell (SSC) homing to the basal membrane niche. The methodology used provides a powerful tool to study the role of other factors in

  15. Propagation of Human Spermatogonial Stem Cells In Vitro

    NARCIS (Netherlands)

    Sadri-Ardekani, Hooman; Mizrak, Sefika C.; van Daalen, Saskia K. M.; Korver, Cindy M.; Roepers-Gajadien, Hermien L.; Koruji, Morteza; Hovingh, Suzanne; de Reijke, Theo M.; de La Rosette, Jean J. M. C. H.; van der Veen, Fulco; de Rooij, Dirk G.; Repping, Sjoerd; van Pelt, Ans M. M.

    2009-01-01

    Context Young boys treated with high-dose chemotherapy are often confronted with infertility once they reach adulthood. Cryopreserving testicular tissue before chemotherapy and autotransplantation of spermatogonial stem cells at a later stage could theoretically allow for restoration of fertility.

  16. Spermatogonial stem cell transplantation and male infertility: Current status and future directions

    Directory of Open Access Journals (Sweden)

    Connor M. Forbes

    2018-03-01

    Full Text Available Objective: To summarise the current state of research into spermatogonial stem cell (SSC therapies with a focus on future directions, as SSCs show promise as a source for preserving or initiating fertility in otherwise infertile men. Materials and methods: We performed a search for publications addressing spermatogonial stem cell transplantation in the treatment of male infertility. The search engines PubMed and Google Scholar were used from 1990 to 2017. Search terms were relevant for spermatogonial stem cell therapies. Titles of publications were screened for relevance; abstracts were read, if related and full papers were reviewed for directly pertinent original research. Results: In all, 58 papers were found to be relevant to this review, and were included in appropriate subheadings. This review discusses the various techniques that SSCs are being investigated to treat forms of male infertility. Conclusions: Evidence does not yet support clinical application of SSCs in humans. However, significant progress in the in vitro and in vivo development of SSCs, including differentiation into functional germ cells, gives reason for cautious optimism for future research. Keywords: Non-obstructive azoospermia, Fertility preservation, Onco-fertility, Male infertility, Stem cell therapy, Allograft

  17. Spermatogonial stem cell transplantation and male infertility: Current status and future directions.

    Science.gov (United States)

    Forbes, Connor M; Flannigan, Ryan; Schlegel, Peter N

    2018-03-01

    To summarise the current state of research into spermatogonial stem cell (SSC) therapies with a focus on future directions, as SSCs show promise as a source for preserving or initiating fertility in otherwise infertile men. We performed a search for publications addressing spermatogonial stem cell transplantation in the treatment of male infertility. The search engines PubMed and Google Scholar were used from 1990 to 2017. Search terms were relevant for spermatogonial stem cell therapies. Titles of publications were screened for relevance; abstracts were read, if related and full papers were reviewed for directly pertinent original research. In all, 58 papers were found to be relevant to this review, and were included in appropriate subheadings. This review discusses the various techniques that SSCs are being investigated to treat forms of male infertility. Evidence does not yet support clinical application of SSCs in humans. However, significant progress in the in vitro and in vivo development of SSCs, including differentiation into functional germ cells, gives reason for cautious optimism for future research.

  18. Human spermatogonial stem cells display limited proliferation in vitro under mouse spermatogonial stem cell culture conditions.

    Science.gov (United States)

    Medrano, Jose V; Rombaut, Charlotte; Simon, Carlos; Pellicer, Antonio; Goossens, Ellen

    2016-11-01

    To study the ability of human spermatogonial stem cells (hSSCs) to proliferate in vitro under mouse spermatogonial stem cell (mSSC) culture conditions. Experimental basic science study. Reproductive biology laboratory. Cryopreserved testicular tissue with normal spermatogenesis obtained from three donors subjected to orchiectomy due to a prostate cancer treatment. Testicular cells used to create in vitro cell cultures corresponding to the following groups: [1] unsorted human testicular cells, [2] differentially plated human testicular cells, and [3] cells enriched with major histocompatibility complex class 1 (HLA - )/epithelial cell surface antigen (EPCAM + ) in coculture with inactivated testicular feeders from the same patient. Analyses and characterization including immunocytochemistry and quantitative reverse-transcription polymerase chain reaction for somatic and germ cell markers, testosterone and inhibin B quantification, and TUNEL assay. Putative hSSCs appeared in singlets, doublets, or small groups of up to four cells in vitro only when testicular cells were cultured in StemPro-34 medium supplemented with glial cell line-derived neurotrophic factor (GDNF), leukemia inhibitory factor (LIF), basic fibroblast growth factor (bFGF), and epidermal growth factor (EGF). Fluorescence-activated cell sorting with HLA - /EPCAM + resulted in an enrichment of 27% VASA + /UTF1 + hSSCs, compared to 13% in unsorted controls. Coculture of sorted cells with inactivated testicular feeders gave rise to an average density of 112 hSSCs/cm 2 after 2 weeks in vitro compared with unsorted cells (61 hSSCs/cm 2 ) and differentially plated cells (49 hSSCS/cm 2 ). However, putative hSSCs rarely stained positive for the proliferation marker Ki67, and their presence was reduced to the point of almost disappearing after 4 weeks in vitro. We found that hSSCs show limited proliferation in vitro under mSSC culture conditions. Coculture of HLA - /EPCAM + sorted cells with testicular

  19. Epigenetic profiles signify cell fate plasticity in unipotent spermatogonial stem and progenitor cells.

    Science.gov (United States)

    Liu, Ying; Giannopoulou, Eugenia G; Wen, Duancheng; Falciatori, Ilaria; Elemento, Olivier; Allis, C David; Rafii, Shahin; Seandel, Marco

    2016-04-27

    Spermatogonial stem and progenitor cells (SSCs) generate adult male gametes. During in vitro expansion, these unipotent murine cells spontaneously convert to multipotent adult spermatogonial-derived stem cells (MASCs). Here we investigate this conversion process through integrative transcriptomic and epigenomic analyses. We find in SSCs that promoters essential to maintenance and differentiation of embryonic stem cells (ESCs) are enriched with histone H3-lysine4 and -lysine 27 trimethylations. These bivalent modifications are maintained at most somatic promoters after conversion, bestowing MASCs an ESC-like promoter chromatin. At enhancers, the core pluripotency circuitry is activated partially in SSCs and completely in MASCs, concomitant with loss of germ cell-specific gene expression and initiation of embryonic-like programs. Furthermore, SSCs in vitro maintain the epigenomic characteristics of germ cells in vivo. Our observations suggest that SSCs encode innate plasticity through the epigenome and that both conversion of promoter chromatin states and activation of cell type-specific enhancers are prominent features of reprogramming.

  20. Plasticity of spermatogonial stem cells

    Directory of Open Access Journals (Sweden)

    Paul S Cooke

    2015-06-01

    Full Text Available There have been significant breakthroughs over the past decade in the development and use of pluripotent stem cells as a potential source of cells for applications in regenerative medicine. It is likely that this methodology will begin to play an important role in human clinical medicine in the years to come. This review describes the plasticity of one type of pluripotent cell, spermatogonial stem cells (SSCs, and their potential therapeutic applications in regenerative medicine and male infertility. Normally, SSCs give rise to sperm when in the testis. However, both human and murine SSCs can give rise to cells with embryonic stem (ES cell-like characteristics that can be directed to differentiate into tissues of all three embryonic germ layers when placed in an appropriate inductive microenvironment, which is in contrast to other postnatal stem cells. Previous studies have reported that SSCs expressed an intermediate pluripotent phenotype before differentiating into a specific cell type and that extended culture was necessary for this to occur. However, recent studies from our group using a tissue recombination model demonstrated that SSCs differentiated rapidly into another tissue, in this case, prostatic epithelium, without expression of pluripotent ES cell markers before differentiation. These results suggest that SSCs are capable of directly differentiating into other cell types without going through an intermediate ES cell-like stage. Because SSCs do not require reprogramming to achieve a pluripotent state, they are an attractive source of pluripotent cells for use in regenerative medicine.

  1. Melatonin improves spermatogonial stem cells transplantation efficiency in azoospermic mice

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    Mohammadreza Gholami

    2014-02-01

    Conclusion: Administration of melatonin (20 mg/kg simultaneously with transplantation of spermatogonial stem cells in azoospermia mouse testis increases the efficiency of transplantation and improves structural properties of the testes tissue.

  2. Genome editing in mouse spermatogonial stem/progenitor cells using engineered nucleases.

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    Danielle A Fanslow

    Full Text Available Editing the genome to create specific sequence modifications is a powerful way to study gene function and promises future applicability to gene therapy. Creation of precise modifications requires homologous recombination, a very rare event in most cell types that can be stimulated by introducing a double strand break near the target sequence. One method to create a double strand break in a particular sequence is with a custom designed nuclease. We used engineered nucleases to stimulate homologous recombination to correct a mutant gene in mouse "GS" (germline stem cells, testicular derived cell cultures containing spermatogonial stem cells and progenitor cells. We demonstrated that gene-corrected cells maintained several properties of spermatogonial stem/progenitor cells including the ability to colonize following testicular transplantation. This proof of concept for genome editing in GS cells impacts both cell therapy and basic research given the potential for GS cells to be propagated in vitro, contribute to the germline in vivo following testicular transplantation or become reprogrammed to pluripotency in vitro.

  3. Spermatogonial stem cells from domestic animals: progress and prospects.

    Science.gov (United States)

    Zheng, Yi; Zhang, Yaqing; Qu, Rongfeng; He, Ying; Tian, Xiue; Zeng, Wenxian

    2014-03-01

    Spermatogenesis, an elaborate and male-specific process in adult testes by which a number of spermatozoa are produced constantly for male fertility, relies on spermatogonial stem cells (SSCs). As a sub-population of undifferentiated spermatogonia, SSCs are capable of both self-renewal (to maintain sufficient quantities) and differentiation into mature spermatozoa. SSCs are able to convert to pluripotent stem cells during in vitro culture, thus they could function as substitutes for human embryonic stem cells without ethical issues. In addition, this process does not require exogenous transcription factors necessary to produce induced-pluripotent stem cells from somatic cells. Moreover, combining genetic engineering with germ cell transplantation would greatly facilitate the generation of transgenic animals. Since germ cell transplantation into infertile recipient testes was first established in 1994, in vivo and in vitro study and manipulation of SSCs in rodent testes have been progressing at a staggering rate. By contrast, their counterparts in domestic animals, despite the failure to reach a comparable level, still burgeoned and showed striking advances. This review outlines the recent progressions of characterization, isolation, in vitro propagation, and transplantation of spermatogonia/SSCs from domestic animals, thereby shedding light on future exploration of these cells with high value, as well as contributing to the development of reproductive technology for large animals.

  4. Differentiation of bovine spermatogonial stem cells into osteoblasts.

    Science.gov (United States)

    Qasemi-Panahi, Babak; Tajik, Parviz; Movahedin, Mansoureh; Moghaddam, Gholamali; Barzgar, Younes; Heidari-Vala, Hamed

    2011-07-01

    Spermatogonial Stem Cell (SSC) technologies provide multiple opportunities for research in the field of biotechnology and regenerative medicine. The therapeutic use of Embryonic Stem Cells (ESCs) is restricted due to severe ethical and immunological concerns. Therefore, we need a new pluripotent cell type. Despite well-known role of germ cells in the gametogenesis, some facts apparently show their multipotentiality. In the present study, bovine SSCs were co-cultured with Sertoli cell for 7 days. Sertoli cells and SSCs were identified by Vimentin and Oct-4 immunocytochemical staining method, respectively. In order to differentiate SSCs into osteoblasts, we used consecutive inducer media without separation of the colonies. We characterized osteoblasts using Alizarin red staining.

  5. ROS Are Required for Mouse Spermatogonial Stem Cell Self-Renewal

    OpenAIRE

    Morimoto, Hiroko; Iwata, Kazumi; Ogonuki, Narumi; Inoue, Kimiko; Ogura, Atsuo; Kanatsu-Shinohara, Mito; Morimoto, Takeshi; Yabe-Nishimura, Chihiro; Shinohara, Takashi

    2013-01-01

    Reactive oxygen species (ROS) generation is implicated in stem cell self-renewal in several tissues but is thought to be detrimental for spermatogenesis as well as spermatogonial stem cells (SSCs). Using cultured SSCs, we show that ROS are generated via the AKT and MEK signaling pathways under conditions where the growth factors glial cell line-derived neurotrophic factor and fibroblast growth factor 2 drive SSC self-renewal and, instead, stimulate self-renewal at physiological levels. SSCs d...

  6. Relationship between spermatogonial stem cell survival and testis function after cytotoxic therapy

    International Nuclear Information System (INIS)

    Meistrich, M.L.

    1986-01-01

    This review, with substantial bibliography, concludes that the acute effects of radiation and cytotoxic drugs are a result of toxicity to the most sensitive of the germ cells, which in most cases are the differentiating spermatogonia. Long-term sterility or reduction in sperm production depends directly on killing of spermatogonial stem cells. For a variety of cytotoxic agents, the same relationship holds between the stem cell survival index and the prompt recovery level of sperm production (at 56 days), the maximal recovered level of sperm production, and the time required for fertility to return. It also appears that the spermatogonial stem cell is the target for long-term sterility in man following cytotoxic therapy. It is not known whether the delay in recovery is a result of this direct damage to the stem cell or an effect on another target cell in the tissue. Data obtained in both experimental animals and man indicate very little direct changes in the secretory cells and other stromal cells of the testis, and there is no evidence as yet that any alterations in these cells adversely affect sperm production or reproductive performance. (UK)

  7. The niche-derived glial cell line-derived neurotrophic factor (GDNF induces migration of mouse spermatogonial stem/progenitor cells.

    Directory of Open Access Journals (Sweden)

    Lisa Dovere

    Full Text Available In mammals, the biological activity of the stem/progenitor compartment sustains production of mature gametes through spermatogenesis. Spermatogonial stem cells and their progeny belong to the class of undifferentiated spermatogonia, a germ cell population found on the basal membrane of the seminiferous tubules. A large body of evidence has demonstrated that glial cell line-derived neurotrophic factor (GDNF, a Sertoli-derived factor, is essential for in vivo and in vitro stem cell self-renewal. However, the mechanisms underlying this activity are not completely understood. In this study, we show that GDNF induces dose-dependent directional migration of freshly selected undifferentiated spermatogonia, as well as germline stem cells in culture, using a Boyden chamber assay. GDNF-induced migration is dependent on the expression of the GDNF co-receptor GFRA1, as shown by migration assays performed on parental and GFRA1-transduced GC-1 spermatogonial cell lines. We found that the actin regulatory protein vasodilator-stimulated phosphoprotein (VASP is specifically expressed in undifferentiated spermatogonia. VASP belongs to the ENA/VASP family of proteins implicated in actin-dependent processes, such as fibroblast migration, axon guidance, and cell adhesion. In intact seminiferous tubules and germline stem cell cultures, GDNF treatment up-regulates VASP in a dose-dependent fashion. These data identify a novel role for the niche-derived factor GDNF, and they suggest that GDNF may impinge on the stem/progenitor compartment, affecting the actin cytoskeleton and cell migration.

  8. Extrinsic and intrinsic factors controlling spermatogonial stem cell self-renewal and differentiation

    OpenAIRE

    Mei, Xing-Xing; Wang, Jian; Wu, Ji

    2015-01-01

    Spermatogonial stem cells (SSCs), the stem cells responsible for male fertility, are one of a small number of cells with the abilities of both self-renewal and generation of large numbers of haploid cells. Technology improvements, most importantly, transplantation assays and in vitro culture systems have greatly expanded our understanding of SSC self-renewal and differentiation. Many important molecules crucial for the balance between self-renewal and differentiation have been recently identi...

  9. In Vitro Derivation and Propagation of Spermatogonial Stem Cell Activity from Mouse Pluripotent Stem Cells.

    Science.gov (United States)

    Ishikura, Yukiko; Yabuta, Yukihiro; Ohta, Hiroshi; Hayashi, Katsuhiko; Nakamura, Tomonori; Okamoto, Ikuhiro; Yamamoto, Takuya; Kurimoto, Kazuki; Shirane, Kenjiro; Sasaki, Hiroyuki; Saitou, Mitinori

    2016-12-06

    The in vitro derivation and propagation of spermatogonial stem cells (SSCs) from pluripotent stem cells (PSCs) is a key goal in reproductive science. We show here that when aggregated with embryonic testicular somatic cells (reconstituted testes), primordial germ cell-like cells (PGCLCs) induced from mouse embryonic stem cells differentiate into spermatogonia-like cells in vitro and are expandable as cells that resemble germline stem cells (GSCs), a primary cell line with SSC activity. Remarkably, GSC-like cells (GSCLCs), but not PGCLCs, colonize adult testes and, albeit less effectively than GSCs, contribute to spermatogenesis and fertile offspring. Whole-genome analyses reveal that GSCLCs exhibit aberrant methylation at vulnerable regulatory elements, including those critical for spermatogenesis, which may restrain their spermatogenic potential. Our study establishes a strategy for the in vitro derivation of SSC activity from PSCs, which, we propose, relies on faithful epigenomic regulation. Copyright © 2016 The Author(s). Published by Elsevier Inc. All rights reserved.

  10. Differential effects of fractionated X irradiation on mouse spermatogonial stem cells

    NARCIS (Netherlands)

    van der Meer, Y.; Huiskamp, R.; Davids, J. A.; de rooij, D. G.

    1993-01-01

    The response of spermatogonial stem cells to fractionated X irradiation was studied in the various stages of the spermatogenic cycle of the CBA mouse. Fractionated doses of 2 + 2, 1 + 3, and 3 + 1 Gy with a 24-h interval between the doses were compared with a single dose of 4 Gy. The numbers of

  11. The roles of Sertoli cells in fate determinations of spermatogonial stem cells

    Directory of Open Access Journals (Sweden)

    Maryam Khanehzad

    2016-03-01

    Full Text Available Background: Spermatogenesis is a complex and highly organized process of proliferation and differentiation of spermatogonial stem cells. Spermatogonial stem cells (SSCs as a unique stem cell have the potential to self-renewal, differentiation and transmit genetic information to the next generation and play a vital role in maintaining fertility. Sertoli cells as the only somatic cells within the seminiferous epithelium play central roles in the formation of niche and balance between self-renewal and differentiation by secrete many growth factors. Given the importance and widespread use of SSCs, particularly in the treatment of infertility, the aim of this study was to create an optimal environment for the proliferation of SSCs. So we decided to study of undifferentiated (ID4 and differentiated (c-Kit gene expression in SSCs followed by co-culture with Sertoli cells for a one-month. Methods: This experimental study was conducted from November 2013 to December 2014 in Department of Anatomy, School of Medicine, Tehran University of Medical Sciences, on immature NMRI mouse (6-3 days old. Initially, Sertoli cells and SSCs were isolated from neonates mouse testes during the two-step enzymatic digestion characteristics Sertoli cells with vimentin marker and SSCs with promyelocytic leukemia zinc-finger (PLZF marker were confirmed. Then SSCs were cultured in two groups: co-culture with Sertoli and without co-culture (control. Undifferentiated (ID4 and differentiation (c-Kit gene expression were evaluated by Real-time PCR technique. Results: Spermatogonial stem cells purity was obtained 66.91% by flow cytometry. The relative expression levels of gene ID4 in co-culture group at the end of each week, compared to the control group showed a significant increase (P<0.05. While the expression of this gene significantly decreased in each group over time (P<0.05. The results of the comparison of the relative expression of c-Kit gene in co-culture group are

  12. NANOS2 acts downstream of glial cell line-derived neurotrophic factor signaling to suppress differentiation of spermatogonial stem cells.

    Science.gov (United States)

    Sada, Aiko; Hasegawa, Kazuteru; Pin, Pui Han; Saga, Yumiko

    2012-02-01

    Stem cells are maintained by both stem cell-extrinsic niche signals and stem cell-intrinsic factors. During murine spermatogenesis, glial cell line-derived neurotrophic factor (GDNF) signal emanated from Sertoli cells and germ cell-intrinsic factor NANOS2 represent key regulators for the maintenance of spermatogonial stem cells. However, it remains unclear how these factors intersect in stem cells to control their cellular state. Here, we show that GDNF signaling is essential to maintain NANOS2 expression, and overexpression of Nanos2 can alleviate the stem cell loss phenotype caused by the depletion of Gfra1, a receptor for GDNF. By using an inducible Cre-loxP system, we show that NANOS2 expression is downregulated upon the conditional knockout (cKO) of Gfra1, while ectopic expression of Nanos2 in GFRA1-negative spermatogonia does not induce de novo GFRA1 expression. Furthermore, overexpression of Nanos2 in the Gfra1-cKO testes prevents precocious differentiation of the Gfra1-knockout stem cells and partially rescues the stem cell loss phenotypes of Gfra1-deficient mice, indicating that the stem cell differentiation can be suppressed by NANOS2 even in the absence of GDNF signaling. Taken together, we suggest that NANOS2 acts downstream of GDNF signaling to maintain undifferentiated state of spermatogonial stem cells. Copyright © 2011 AlphaMed Press.

  13. Parental desire and acceptability of spermatogonial stem cell cryopreservation in boys with cancer

    NARCIS (Netherlands)

    van den Berg, H.; Repping, S.; van der Veen, F.

    2007-01-01

    BACKGROUND: In the near future, a substantial proportion of adults will be childhood cancer survivors. The cryopreservation and transplantation of spermatogonial stem cells (SSCs) is currently successful in animals; application in humans seems likely in the near future. Cryopreserving SSCs might

  14. Transfection of bovine spermatogonial stem cells in vitro.

    Science.gov (United States)

    Tajik, P; Hoseini Pajooh, Kh; Fazle Elahi, Z; Javdani Shahedin, G; Ghasemzadeh-Nava, H

    2017-01-01

    Spermatogonial stem cells (SSCs) are the only stem cells in adults that can transfer genetic information to the future generations. Considering the fact that a single SSC gives rise to a vast number of spermatozoa, genetic manipulation of these cells is a potential novel technology with feasible application to various animal species. The aim of this study was to evaluate enhanced green fluorescent protein (EGFP) gene transfection into bovine SSCs via liposome carrier and assess the best incubation day in uptake exogenous gene by SSCs. Transfection efficiency of EGFP gene with lipofectamine 2000 was determined in days following each three day of transfection (day 4, 6 and 8 of the culture) by fluorescent microscope. Results showed that the transfected cells through lipofection increased significantly (Ptransfection in comparison with those of the control groups. The transfected SSCs were higher in comparison with those of the free exogenous gene carrier groups (Ptransfection proceeds at day four. It was concluded that lipofectamine can be used safely for direct loading exogenous DNA to SSCs particularly during the fourth day of culture.

  15. Extrinsic and intrinsic factors controlling spermatogonial stem cell self-renewal and differentiation

    Directory of Open Access Journals (Sweden)

    Xing-Xing Mei

    2015-06-01

    Full Text Available Spermatogonial stem cells (SSCs, the stem cells responsible for male fertility, are one of a small number of cells with the abilities of both self-renewal and generation of large numbers of haploid cells. Technology improvements, most importantly, transplantation assays and in vitro culture systems have greatly expanded our understanding of SSC self-renewal and differentiation. Many important molecules crucial for the balance between self-renewal and differentiation have been recently identified although the exact mechanism(s remain largely undefined. In this review, we give a brief introduction to SSCs, and then focus on extrinsic and intrinsic factors controlling SSCs self-renewal and differentiation.

  16. Extrinsic and intrinsic factors controlling spermatogonial stem cell self-renewal and differentiation.

    Science.gov (United States)

    Mei, Xing-Xing; Wang, Jian; Wu, Ji

    2015-01-01

    Spermatogonial stem cells (SSCs), the stem cells responsible for male fertility, are one of a small number of cells with the abilities of both self-renewal and generation of large numbers of haploid cells. Technology improvements, most importantly, transplantation assays and in vitro culture systems have greatly expanded our understanding of SSC self-renewal and differentiation. Many important molecules crucial for the balance between self-renewal and differentiation have been recently identified although the exact mechanism(s) remain largely undefined. In this review, we give a brief introduction to SSCs, and then focus on extrinsic and intrinsic factors controlling SSCs self-renewal and differentiation.

  17. In vitro toxicity assay of cisplatin on mouse acute lymphoblastic leukaemia and spermatogonial stem cells.

    Science.gov (United States)

    Shabani, R; Ashtari, K; Behnam, B; Izadyar, F; Asgari, H; Asghari Jafarabadi, M; Ashjari, M; Asadi, E; Koruji, M

    2016-06-01

    Testicular cancer is the most common cancer affecting men in reproductive age, and cisplatin is one of the major helpful chemotherapeutic agents for treatment of this cancer. In addition, exposure of testes cancer cells to cisplatin could potentially eliminate tumour cells from germ cells in patients. The aim of this study was to evaluate the effect of cisplatin on viability of mouse acute lymphoblastic leukaemia cell line (EL-4) and neonatal mouse spermatogonial cells in vitro. In this study, the isolated spermatogonial stem cells (SSC) and EL-4 were divided into six groups including control (received medium), sham (received DMSO in medium) and experimental groups which received different doses of cisplatin (0.5, 5, 10 and 15 μg ml(-1) ). Cells viability was evaluated with MTT assay. The identity of the cultured cells was confirmed by the expression of specific markers. Our finding showed that viability of both SSC and EL-4 cells was reduced with the dose of 15 μg/ml when compared to the control group (P ≤ 0.05). Also, the differences between the IC50 in doses 10 and 15 μg/ml at different time were significant (P ≤ 0.05). The number of TUNEL-positive cells was increased, and the BAX and caspase-3 expressions were upregulated in EL4 cells for group that received an effective dose of cisplatin). In conclusion, despite the dramatic effects of cisplatin on both cells, spermatogonial stem cells could form colony in culture. © 2015 Blackwell Verlag GmbH.

  18. Oocyte-like cells induced from mouse spermatogonial stem cells.

    Science.gov (United States)

    Wang, Lu; Cao, Jinping; Ji, Ping; Zhang, Di; Ma, Lianghong; Dym, Martin; Yu, Zhuo; Feng, Lixin

    2012-08-06

    During normal development primordial germ cells (PGCs) derived from the epiblast are the precursors of spermatogonia and oogonia. In culture, PGCs can be induced to dedifferentiate to pluripotent embryonic germ (EG) cells in the presence of various growth factors. Several recent studies have now demonstrated that spermatogonial stem cells (SSCs) can also revert back to pluripotency as embryonic stem (ES)-like cells under certain culture conditions. However, the potential dedifferentiation of SSCs into PGCs or the potential generation of oocytes from SSCs has not been demonstrated before. We report that mouse male SSCs can be converted into oocyte-like cells in culture. These SSCs-derived oocytes (SSC-Oocs) were similar in size to normal mouse mature oocytes. They expressed oocyte-specific markers and gave rise to embryos through parthenogenesis. Interestingly, the Y- and X-linked testis-specific genes in these SSC-Oocs were significantly down-regulated or turned off, while oocyte-specific X-linked genes were activated. The gene expression profile appeared to switch to that of the oocyte across the X chromosome. Furthermore, these oocyte-like cells lost paternal imprinting but acquired maternal imprinting. Our data demonstrate that SSCs might maintain the potential to be reprogrammed into oocytes with corresponding epigenetic reversals. This study provides not only further evidence for the remarkable plasticity of SSCs but also a potential system for dissecting molecular and epigenetic regulations in germ cell fate determination and imprinting establishment during gametogenesis.

  19. Oocyte-like cells induced from mouse spermatogonial stem cells

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    Wang Lu

    2012-08-01

    Full Text Available Abstract Background During normal development primordial germ cells (PGCs derived from the epiblast are the precursors of spermatogonia and oogonia. In culture, PGCs can be induced to dedifferentiate to pluripotent embryonic germ (EG cells in the presence of various growth factors. Several recent studies have now demonstrated that spermatogonial stem cells (SSCs can also revert back to pluripotency as embryonic stem (ES-like cells under certain culture conditions. However, the potential dedifferentiation of SSCs into PGCs or the potential generation of oocytes from SSCs has not been demonstrated before. Results We report that mouse male SSCs can be converted into oocyte-like cells in culture. These SSCs-derived oocytes (SSC-Oocs were similar in size to normal mouse mature oocytes. They expressed oocyte-specific markers and gave rise to embryos through parthenogenesis. Interestingly, the Y- and X-linked testis-specific genes in these SSC-Oocs were significantly down-regulated or turned off, while oocyte-specific X-linked genes were activated. The gene expression profile appeared to switch to that of the oocyte across the X chromosome. Furthermore, these oocyte-like cells lost paternal imprinting but acquired maternal imprinting. Conclusions Our data demonstrate that SSCs might maintain the potential to be reprogrammed into oocytes with corresponding epigenetic reversals. This study provides not only further evidence for the remarkable plasticity of SSCs but also a potential system for dissecting molecular and epigenetic regulations in germ cell fate determination and imprinting establishment during gametogenesis.

  20. Retinoic acid combined with spermatogonial stem cell conditions facilitate the generation of mouse germ-like cells

    DEFF Research Database (Denmark)

    Dong, Guoyi; Shang, Zhouchun; Liu, Longqi

    2017-01-01

    Spermatogenic lineage has been directly generated in spermatogonial stem cell (SSC) conditions from human pluripotent stem cells (PSCs). However, it remains unknown whether mouse embryonic stem cells (ESCs) can directly differentiate into advanced male germ cell lineage in the same conditions. Here......, we showed rather low efficiency of germ-like cell generation from mouse ESCs in SSC conditions. Interestingly, addition of retinoic acid (RA) into SSC conditions enabled efficient differentiation of mouse ESCs into germ-like cells, as shown by the activation of spermatogenesis-associated genes...... such as Mvh, Dazl, Prdm14, Stella, Scp1, Scp3, Stra8 and Rec8. In contrast, for cells cultured in control medium, the activation of the above genes barely occurred. In addition, RA with SSC conditions yielded colonies of Acrosin-expressing cells and the positive ratio reached a peak at day 6. Our work thus...

  1. [Fertility preservation in boys: spermatogonial stem cell transplantation and testicular grafting].

    Science.gov (United States)

    Goossens, E; Tournaye, H

    2013-09-01

    Spermatogonial stem cells (SSC) are the founder cells of spermatogenesis and are responsible for the lifelong production of spermatozoa. The cryopreservation and transplantation of these cells has been proposed as a fertility preservation strategy for young boys at risk for stem cell loss, i.e. patients undergoing chemotherapy for cancer or as a conditioning treatment for bone marrow transplantation. To prevent lifelong sterility in boys, two fertility restoration strategies are being developed: the injection of SSC and the grafting of testicular tissue containing SSC. Depending on the disease of the patient one of these two approaches will be applicable. Grafting has the advantage that SSC can reside within their natural niche, preserving the interactions between germ cells and their supporting cells and may therefore be regarded as the first choice strategy. However, in cases where the risk for malignant contamination of the testicular tissue is real, e.g. leukemia, transplantation of SSC by injection is preferable over grafting. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

  2. DMRT1 Is Required for Mouse Spermatogonial Stem Cell Maintenance and Replenishment.

    Science.gov (United States)

    Zhang, Teng; Oatley, Jon; Bardwell, Vivian J; Zarkower, David

    2016-09-01

    Male mammals produce sperm for most of postnatal life and therefore require a robust germ line stem cell system, with precise balance between self-renewal and differentiation. Prior work established doublesex- and mab-3-related transcription factor 1 (Dmrt1) as a conserved transcriptional regulator of male sexual differentiation. Here we investigate the role of Dmrt1 in mouse spermatogonial stem cell (SSC) homeostasis. We find that Dmrt1 maintains SSCs during steady state spermatogenesis, where it regulates expression of Plzf, another transcription factor required for SSC maintenance. We also find that Dmrt1 is required for recovery of spermatogenesis after germ cell depletion. Committed progenitor cells expressing Ngn3 normally do not contribute to SSCs marked by the Id4-Gfp transgene, but do so when spermatogonia are chemically depleted using busulfan. Removal of Dmrt1 from Ngn3-positive germ cells blocks the replenishment of Id4-GFP-positive SSCs and recovery of spermatogenesis after busulfan treatment. Our data therefore reveal that Dmrt1 supports SSC maintenance in two ways: allowing SSCs to remain in the stem cell pool under normal conditions; and enabling progenitor cells to help restore the stem cell pool after germ cell depletion.

  3. Enhanced spermatogonial stem cell killing and reduced translocation yield from X-irradiated 101/H mice

    Energy Technology Data Exchange (ETDEWEB)

    Cattanach, B M; Kirk, M J

    1987-01-01

    The spermatogonial stem cells of 101/H mice have been found to be more sensitive to killing by acute X-ray doses than those of the 'standard' C3H/HeH x 101/H F/sub 1/ hybrid. Duration of the sterile period was longer throughout the 0.5-8.0-Gy dose range tested and 'recovered' testis weights, taken after recovery of fertility, were more severely reduced. The shapes of the sterile period dose-response curves were similar, but with the 101/H mice the plateau occurred at 3-5 Gy, rather than at 6 Gy. An equivalent observation was made with the testis weight data. The translocation dose-response curve was bell-shaped, as previously found with the hybrid, but yields were lower at all but the lowest doses. Notably, peak yields occurred at 3-5 Gy, rather than at 6 Gy. The altered stem cell killing and genetic responses may be explained either by a higher proportion of radiosensitive cells in the heterogeneous stem cell population or by a higher ratio of cell killing to recoverable chromosome damage which might imply a reduced repair capacity. (Auth.). 43 refs.; 5 figs.; 5 tabs.

  4. Assessment of Culture Condition and In Vitro Colonization Ability of Human Spermatogonial Stem Cells: A Review Article

    Directory of Open Access Journals (Sweden)

    Maryam Mahal Dashtian

    2013-06-01

    Full Text Available Spermatogenesis is a highly complex and regulated process in which germ stem cells differentiate into spermatozoa. These stem cells, called spermatogonial stem cells (SSCs, are in the base of seminiferous tubules and have the ability of self-renewal and differentiation into functional germ cells. Due to this ability, SSCs can restore spermatogenesis after testicular damage caused by cytotoxic materials or following transplantation into an infertile recipient. Therefore, self-renewal of these cells is critical for the preservation of SSC populations and restoration of fertility. While previous studies have shown that the SSCs of mice and other species can survive and proliferate for long periods of time, little information is available about suitable culture media for the growth of human SSCs. Identification of SSC markers allows for the isolation of these populations of cells. The isolated cell can be expanded in culture and transplanted into infertile recipients. Consequently, the recognition of markers and the establishment of long-term culture systems for human SSCs will be essential for using the potential of these cells in a clinical setting. In this article, we focus on the markers that have been identified for human SSCs and in vitro culture techniques used for human SSCs proliferation.

  5. Macrophages Contribute to the Spermatogonial Niche in the Adult Testis

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    Tony DeFalco

    2015-08-01

    Full Text Available The testis produces sperm throughout the male reproductive lifespan by balancing self-renewal and differentiation of spermatogonial stem cells (SSCs. Part of the SSC niche is thought to lie outside the seminiferous tubules of the testis; however, specific interstitial components of the niche that regulate spermatogonial divisions and differentiation remain undefined. We identified distinct populations of testicular macrophages, one of which lies on the surface of seminiferous tubules, in close apposition to areas of tubules enriched for undifferentiated spermatogonia. These macrophages express spermatogonial proliferation- and differentiation-inducing factors, such as colony-stimulating factor 1 (CSF1 and enzymes involved in retinoic acid (RA biosynthesis. We show that transient depletion of macrophages leads to a disruption in spermatogonial differentiation. These findings reveal an unexpected role for macrophages in the spermatogonial niche in the testis and raise the possibility that macrophages play previously unappreciated roles in stem/progenitor cell regulation in other tissues.

  6. Spermatogonial stem cell markers and niche in equids.

    Directory of Open Access Journals (Sweden)

    Guilherme M J Costa

    Full Text Available Spermatogonial stem cells (SSCs are the foundation of spermatogenesis and are located in a highly dynamic microenvironment called "niche" that influences all aspects of stem cell function, including homing, self-renewal and differentiation. Several studies have recently identified specific proteins that regulate the fate of SSCs. These studies also aimed at identifying surface markers that would facilitate the isolation of these cells in different vertebrate species. The present study is the first to investigate SSC physiology and niche in stallions and to offer a comparative evaluation of undifferentiated type A spermatogonia (Aund markers (GFRA1, PLZF and CSF1R in three different domestic equid species (stallions, donkeys, and mules. Aund were first characterized according to their morphology and expression of the GFRA1 receptor. Our findings strongly suggest that in stallions these cells were preferentially located in the areas facing the interstitium, particularly those nearby blood vessels. This distribution is similar to what has been observed in other vertebrate species. In addition, all three Aund markers were expressed in the equid species evaluated in this study. These markers have been well characterized in other mammalian species, which suggests that the molecular mechanisms that maintain the niche and Aund/SSCs physiology are conserved among mammals. We hope that our findings will help future studies needing isolation and cryopreservation of equids SSCs. In addition, our data will be very useful for studies that aim at preserving the germplasm of valuable animals, and involve germ cell transplantation or xenografts of equids testis fragments/germ cells suspensions.

  7. Comparison of Hematopoietic and Spermatogonial Stem Cell Niches from the Regenerative Medicine Aspect.

    Science.gov (United States)

    Köse, Sevil; Yersal, Nilgün; Önen, Selin; Korkusuz, Petek

    2018-06-08

    Recent advances require a dual evaluation of germ and somatic stem cell niches with a regenerative medicine perspective. For a better point of view of the niche concept, it is needed to compare the microenvironments of those niches in respect to several components. The cellular environment of spermatogonial stem cells' niche consists of Sertoli cells, Leydig cells, vascular endothelial cells, epididymal fat cells, peritubular myoid cells while hematopoietic stem cells have mesenchymal stem cells, osteoblasts, osteoclasts, megacaryocytes, macrophages, vascular endothelial cells, pericytes and adipocytes in their microenvironment. Not only those cells', but also the effect of the other factors such as hormones, growth factors, chemokines, cytokines, extracellular matrix components, biomechanical forces (like shear stress, tension or compression) and physical environmental elements such as temperature, oxygen level and pH will be clarified during the chapter. Because it is known that the microenvironment has an important role in the stem cell homeostasis and disease conditions, it is crucial to understand the details of the microenvironment and to be able to compare the niche concepts of the different types of stem cells from each other, for the regenerative interventions. Indeed, the purpose of this chapter is to point out the usage of niche engineering within the further studies in the regenerative medicine field. Decellularized, synthetic or non-synthetic scaffolds may help to mimic the stem cell niche. However, the shared or different characteristics of germ and somatic stem cell microenvironments are necessary to constitute a proper niche model. When considered from this aspect, it is possible to produce some strategies on the personalized medicine by using those artificial models of stem cell microenvironment.

  8. Expression of the chicken GDNF family receptor alpha-1 as a marker of spermatogonial stem cells

    Czech Academy of Sciences Publication Activity Database

    Mucksová, J.; Kalina, J.; Bakst, M.; Yan, H.; Brillard, J.-P.; Benešová, B.; Fafílek, Bohumil; Hejnar, Jiří; Trefil, P.

    2013-01-01

    Roč. 142, 1-2 (2013), s. 75-83 ISSN 0378-4320 R&D Projects: GA ČR GAP502/11/2207 Grant - others:GA MŠk(CZ) ME10104 Institutional support: RVO:68378050 Keywords : GFRα1 * chicken spermatogonial stem cell * male germ line transplantation Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 1.581, year: 2013

  9. Comparison of stem-spermatogonial renewal and mitotic activity in the #betta#-irratiated mouse and rat

    International Nuclear Information System (INIS)

    Erickson, B.H.; Hall, G.G.

    1983-01-01

    The Sprague-Dawley rat exceeds the CRF 1 mouse in number of isolated or purported stem cells per unit area of seminiferous tubule by a factor of 2.1, yet the mouse exceeds the rat in number of first-generation spermatogonia (A 1 ) per unit of tubule by a factor of 1.8. This difference could lead to an interspecies difference in irradiation response and help clarify the identity of spermatogonial stem cell. To test this thesis, mice and rats were irradiated with 600 R of 60 Co #betta#-radiation and killed at postirradiation intervals of 1-16 weeks. Both tubular whole mounts and cross sections were evaluated. The species did not differ in percent survival of isolated spermatogonia, but the mouse exceeded the rat in survival and/or production of A 1 or clonal spermatogonia by a factor of 5. By week 16 after irradiation, the mouse restis had regained 67% of its preirradiation weight, in contrast to the rat's 52%. Clonal renewal was in progress by the end of the 2 (mouse) and 3 (rat) weeks and was substantially complete by the 8 week. In both species the isolated population, however, diminished throughout the first 8 weeks and was renewed between 8 and 16 weeks. Clonal renewal was not accompanied by an increase in the number of isolated spermatogonial mitoses, but was accompanied by increases in the mitotis of pairs and clones and the apparent splitting of existing clones to form additional clones. Thus, the mouse's superiority in the rate and completeness of spermatogonial renewal was apparently due to the attributes of the undifferentiated A 1 spermatogonial clone. (orig.)

  10. Spermatogonial stem cells: Current biotechnological advances in reproduction and regenerative medicine.

    Science.gov (United States)

    Aponte, Pedro Manuel

    2015-05-26

    Spermatogonial stem cells (SSCs) are the germ stem cells of the seminiferous epithelium in the testis. Through the process of spermatogenesis, they produce sperm while concomitantly keeping their cellular pool constant through self-renewal. SSC biology offers important applications for animal reproduction and overcoming human disease through regenerative therapies. To this end, several techniques involving SSCs have been developed and will be covered in this article. SSCs convey genetic information to the next generation, a property that can be exploited for gene targeting. Additionally, SSCs can be induced to become embryonic stem cell-like pluripotent cells in vitro. Updates on SSC transplantation techniques with related applications, such as fertility restoration and preservation of endangered species, are also covered on this article. SSC suspensions can be transplanted to the testis of an animal and this has given the basis for SSC functional assays. This procedure has proven technically demanding in large animals and men. In parallel, testis tissue xenografting, another transplantation technique, was developed and resulted in sperm production in testis explants grafted into ectopical locations in foreign species. Since SSC culture holds a pivotal role in SSC biotechnologies, current advances are overviewed. Finally, spermatogenesis in vitro, already demonstrated in mice, offers great promises to cope with reproductive issues in the farm animal industry and human clinical applications.

  11. Expression dynamics of self-renewal factors for spermatogonial stem cells in the mouse testis.

    Science.gov (United States)

    Sakai, Mizuki; Masaki, Kaito; Aiba, Shota; Tone, Masaaki; Takashima, Seiji

    2018-04-16

    Glial cell line-derived neurotrophic factor (GDNF) and fibroblast growth factor 2 (FGF2) are bona fide self-renewal factors for spermatogonial stem cells (SSCs). Although GDNF is indispensable for the maintenance of SSCs, the role of FGF2 in the testis remains to be elucidated. To clarify this, the expression dynamics and regulatory mechanisms of Fgf2 and Gdnf in the mouse testes were analyzed. It is well known that Sertoli cells express Gdnf, and its receptor is expressed in a subset of undifferentiated spermatogonia, including SSCs. However, we found that Fgf2 was mainly expressed in the germ cells and its receptors were expressed not only in the cultured spermatogonial cell line, but also in testicular somatic cells. Aging, hypophysectomy, retinoic acid treatment, and testicular injury induced distinct Fgf2 and Gdnf expression dynamics, suggesting a difference in the expression mechanism of Fgf2 and Gdnf in the testis. Such differences might cause a dynamic fluctuation of Gdnf/Fgf2 ratio depending on the intrinsic/extrinsic cues. Considering that FGF2-cultured spermatogonia exhibit more differentiated phenotype than those cultured with GDNF, FGF2 might play a role distinct from that of GDNF in the testis, despite the fact that both factors are self-renewal factor for SSC in vitro.

  12. Myc/Mycn-mediated glycolysis enhances mouse spermatogonial stem cell self-renewal.

    Science.gov (United States)

    Kanatsu-Shinohara, Mito; Tanaka, Takashi; Ogonuki, Narumi; Ogura, Atsuo; Morimoto, Hiroko; Cheng, Pei Feng; Eisenman, Robert N; Trumpp, Andreas; Shinohara, Takashi

    2016-12-01

    Myc plays critical roles in the self-renewal division of various stem cell types. In spermatogonial stem cells (SSCs), Myc controls SSC fate decisions because Myc overexpression induces enhanced self-renewal division, while depletion of Max, a Myc-binding partner, leads to meiotic induction. However, the mechanism by which Myc acts on SSC fate is unclear. Here we demonstrate a critical link between Myc/Mycn gene activity and glycolysis in SSC self-renewal. In SSCs, Myc/Mycn are regulated by Foxo1, whose deficiency impairs SSC self-renewal. Myc/Mycn-deficient SSCs not only undergo limited self-renewal division but also display diminished glycolytic activity. While inhibition of glycolysis decreased SSC activity, chemical stimulation of glycolysis or transfection of active Akt1 or Pdpk1 (phosphoinositide-dependent protein kinase 1 ) augmented self-renewal division, and long-term SSC cultures were derived from a nonpermissive strain that showed limited self-renewal division. These results suggested that Myc-mediated glycolysis is an important factor that increases the frequency of SSC self-renewal division. © 2016 Kanatsu-Shinohara et al.; Published by Cold Spring Harbor Laboratory Press.

  13. Quantitative analysis of male germline stem cell differentiation reveals a role for the p53-mTORC1 pathway in spermatogonial maintenance.

    Science.gov (United States)

    Xiong, Mulin; Ferder, Ianina C; Ohguchi, Yasuyo; Wang, Ning

    2015-01-01

    p53 protects cells from DNA damage by inducing cell-cycle arrest upon encountering genomic stress. Among other pathways, p53 elicits such an effect by inhibiting mammalian target of rapamycin complex 1 (mTORC1), the master regulator of cell proliferation and growth. Although recent studies have indicated roles for both p53 and mTORC1 in stem cell maintenance, it remains unclear whether the p53-mTORC1 pathway is conserved to mediate this process under normal physiological conditions. Spermatogenesis is a classic stem cell-dependent process in which undifferentiated spermatogonia undergo self-renewal and differentiation to maintain the lifelong production of spermatozoa. To better understand this process, we have developed a novel flow cytometry (FACS)-based approach that isolates spermatogonia at consecutive differentiation stages. By using this as a tool, we show that genetic loss of p53 augments mTORC1 activity during early spermatogonial differentiation. Functionally, loss of p53 drives spermatogonia out of the undifferentiated state and causes a consistent expansion of early differentiating spermatogonia until the stage of preleptotene (premeiotic) spermatocyte. The frequency of early meiotic spermatocytes is, however, dramatically decreased. Thus, these data suggest that p53-mTORC1 pathway plays a critical role in maintaining the homeostasis of early spermatogonial differentiation. Moreover, our FACS approach could be a valuable tool in understanding spermatogonial differentiation.

  14. Stem-spermatogonial survival and incidence of reciprocal translocations in the γ-irradiated boar

    International Nuclear Information System (INIS)

    Erickson, B.H.; Martin, P.G.

    1984-01-01

    To assess the effects of γ-radiation on stem-cell survival and incidence of reciprocal translocations, boar testes were irradiated with 100, 200, or 400 rad. Stem-cell survival was markedly affected by 100 rad (51% of control) and reduced to 34% of control by 400 rad. Production of differentiating spermatogonia renewal was incomplete at 12 weeks. Incidence of translocations peaked at 200 rad and the number occurring at 100 and 400 rad was similar. Kinetics of porcine spermatogonial renewal differs considerably from those of the rodent and, relative to the rodent, this may account for the boar's higher sensitivity to stem-cell killing and lower sensitivity to translocation

  15. Persistent DNA Damage in Spermatogonial Stem Cells After Fractionated Low-Dose Irradiation of Testicular Tissue

    International Nuclear Information System (INIS)

    Grewenig, Angelika; Schuler, Nadine; Rübe, Claudia E.

    2015-01-01

    Purpose: Testicular spermatogenesis is extremely sensitive to radiation-induced damage, and even low scattered doses to testis from radiation therapy may pose reproductive risks with potential treatment-related infertility. Radiation-induced DNA double-strand breaks (DSBs) represent the greatest threat to the genomic integrity of spermatogonial stem cells (SSCs), which are essential to maintain spermatogenesis and prevent reproduction failure. Methods and Materials: During daily low-dose radiation with 100 mGy or 10 mGy, radiation-induced DSBs were monitored in mouse testis by quantifying 53 binding protein 1 (53BP-1) foci in SSCs within their stem cell niche. The accumulation of DSBs was correlated with proliferation, differentiation, and apoptosis of testicular germ cell populations. Results: Even very low doses of ionizing radiation arrested spermatogenesis, primarily by inducing apoptosis in spermatogonia. Eventual recovery of spermatogenesis depended on the survival of SSCs and their functional ability to proliferate and differentiate to provide adequate numbers of differentiating spermatogonia. Importantly, apoptosis-resistant SSCs resulted in increased 53BP-1 foci levels during, and even several months after, fractionated low-dose radiation, suggesting that surviving SSCs have accumulated an increased load of DNA damage. Conclusions: SSCs revealed elevated levels of DSBs for weeks after radiation, and if these DSBs persist through differentiation to spermatozoa, this may have severe consequences for the genomic integrity of the fertilizing sperm

  16. Persistent DNA Damage in Spermatogonial Stem Cells After Fractionated Low-Dose Irradiation of Testicular Tissue

    Energy Technology Data Exchange (ETDEWEB)

    Grewenig, Angelika; Schuler, Nadine; Rübe, Claudia E., E-mail: claudia.ruebe@uks.eu

    2015-08-01

    Purpose: Testicular spermatogenesis is extremely sensitive to radiation-induced damage, and even low scattered doses to testis from radiation therapy may pose reproductive risks with potential treatment-related infertility. Radiation-induced DNA double-strand breaks (DSBs) represent the greatest threat to the genomic integrity of spermatogonial stem cells (SSCs), which are essential to maintain spermatogenesis and prevent reproduction failure. Methods and Materials: During daily low-dose radiation with 100 mGy or 10 mGy, radiation-induced DSBs were monitored in mouse testis by quantifying 53 binding protein 1 (53BP-1) foci in SSCs within their stem cell niche. The accumulation of DSBs was correlated with proliferation, differentiation, and apoptosis of testicular germ cell populations. Results: Even very low doses of ionizing radiation arrested spermatogenesis, primarily by inducing apoptosis in spermatogonia. Eventual recovery of spermatogenesis depended on the survival of SSCs and their functional ability to proliferate and differentiate to provide adequate numbers of differentiating spermatogonia. Importantly, apoptosis-resistant SSCs resulted in increased 53BP-1 foci levels during, and even several months after, fractionated low-dose radiation, suggesting that surviving SSCs have accumulated an increased load of DNA damage. Conclusions: SSCs revealed elevated levels of DSBs for weeks after radiation, and if these DSBs persist through differentiation to spermatozoa, this may have severe consequences for the genomic integrity of the fertilizing sperm.

  17. Genome Editing in Mouse Spermatogonial Stem Cell Lines Using TALEN and Double-Nicking CRISPR/Cas9

    Directory of Open Access Journals (Sweden)

    Takuya Sato

    2015-07-01

    Full Text Available Mouse spermatogonial stem cells (SSCs can be cultured for multiplication and maintained for long periods while preserving their spermatogenic ability. Although the cultured SSCs, named germline stem (GS cells, are targets of genome modification, this process remains technically difficult. In the present study, we tested TALEN and double-nicking CRISPR/Cas9 on GS cells, targeting Rosa26 and Stra8 loci as representative genes dispensable and indispensable in spermatogenesis, respectively. Harvested GS cell colonies showed a high targeting efficiency with both TALEN and CRISPR/Cas9. The Rosa26-targeted GS cells differentiated into fertility-competent sperm following transplantation. On the other hand, Stra8-targeted GS cells showed defective spermatogenesis following transplantation, confirming its prime role in the initiation of meiosis. TALEN and CRISPR/Cas9, when applied in GS cells, will be valuable tools in the study of spermatogenesis and for revealing the genetic mechanism of spermatogenic failure.

  18. Effect of Antioxidants and Apoptosis Inhibitors on Cryopreservation of Murine Germ Cells Enriched for Spermatogonial Stem Cells.

    Directory of Open Access Journals (Sweden)

    Seung-Jung Ha

    Full Text Available Spermatogonial stem cells (SSCs are germline stem cells that serve as the foundation of spermatogenesis to maintain fertility throughout a male's lifetime. To treat male infertility using stem cell banking systems and transplantation, it is important to be able to preserve SSCs for long periods of time. Therefore, this study was conducted to develop an optimal cryopreservation protocol for SSCs using antioxidants and apoptosis inhibitors in freezing medium. No differences were observed compared to controls when SSCs were cryopreserved in the presence of apoptosis inhibitors by themselves. However, mouse germ cells cryopreserved in basal medium containing the antioxidant hypotaurine (14 mM resulted in significantly greater proliferation potential and mitochondrial activity. Furthermore, treatment groups with combinations containing 200 mM trehalose and 14 mM hypotaurine showed higher proliferation rates compared to controls. In addition, several serum free conditions were evaluated for SSC cryopreservation. Treatment media containing 10% or 20% knockout serum replacement resulted in similar cryopreservation results compared to media containing FBS. SSC transplantation was also performed to confirm the functionality of SSCs frozen in 14 mM hypotaurine. Donor SSCs formed normal spermatogenic colonies and sperm in the recipient testis. These data indicate that inclusion of 14 mM hypotaurine in cryopreservation media is an effective way to efficiently cryopreserve germ cells enriched for SSCs and that knockout serum replacement can replace FBS in germ cell cryopreservation media.

  19. CTNNB1 signaling in sertoli cells downregulates spermatogonial stem cell activity via WNT4.

    Directory of Open Access Journals (Sweden)

    Alexandre Boyer

    Full Text Available Constitutive activation of the WNT signaling effector CTNNB1 (β-catenin in the Sertoli cells of the Ctnnb1(tm1Mmt/+;Amhr2(tm3(creBhr/+ mouse model results in progressive germ cell loss and sterility. In this study, we sought to determine if this phenotype could be due to a loss of spermatogonial stem cell (SSC activity. Reciprocal SSC transplants between Ctnnb1(tm1Mmt/+;Amhr2(tm3(creBhr/+ and wild-type mice showed that SSC activity is lost in Ctnnb1(tm1Mmt/+;Amhr2(tm3(creBhr/+ testes over time, whereas the mutant testes could not support colonization by wild-type SSCs. Microarray analyses performed on cultured Sertoli cells showed that CTNNB1 induces the expression of genes associated with the female sex determination pathway, which was also found to occur in Ctnnb1(tm1Mmt/+;Amhr2(tm3(creBhr/+ testes. One CTNNB1 target gene encoded the secreted signaling molecule WNT4. We therefore tested the effects of WNT4 on SSC-enriched germ cell cultures, and found that WNT4 induced cell death and reduced SSC activity without affecting cell cycle. Conversely, conditional inactivation of Wnt4 in the Ctnnb1(tm1Mmt/+;Amhr2(tm3(creBhr/+ model rescued spermatogenesis and male fertility, indicating that WNT4 is the major effector downstream of CTNNB1 responsible for germ cell loss. Furthermore, WNT4 was found to signal via the CTNNB1 pathway in Sertoli cells, suggesting a self-reinforcing positive feedback loop. Collectively, these data indicate for the first time that ectopic activation of a signaling cascade in the stem cell niche depletes SSC activity through a paracrine factor. These findings may provide insight into the pathogenesis of male infertility, as well as embryonic gonadal development.

  20. Histone methyltransferase SETDB1 maintains survival of mouse spermatogonial stem/progenitor cells via PTEN/AKT/FOXO1 pathway.

    Science.gov (United States)

    Liu, Tiantian; Chen, Xiaoxu; Li, Tianjiao; Li, Xueliang; Lyu, Yinghua; Fan, Xiaoteng; Zhang, Pengfei; Zeng, Wenxian

    2017-10-01

    Spermatogonial stem cells (SSCs) possess the capacity of self-renewal and differentiation, which are the basis of spermatogenesis. In maintenance of SSC homeostasis, intrinsic/extrinsic factors and various signaling pathways tightly control the fate of SSCs. Methyltransferase SETDB1 (Set domain, bifurcated 1) catalyzes histone H3 lysine 9 (H3K9) trimethylation and represses gene expression. SETDB1 is required for maintaining the survival of spermatogonial stem cells in mice. However, the underlying molecular mechanism remains unclear. In the present study, we found that Setdb1 regulates PTEN/AKT/FOXO1 pathway to inhibit SSC apoptosis. Co-immunoprecipitation and reporter gene assay revealed that SETDB1 interacted and coordinated with AKT to regulate FOXO1 activity and expression of the downstream target genes Bim and Puma. Among the SETDB1-bound genes, the H3K9me3 levels on the promoter regions of Bim and Pten decreased in Setdb1-KD group; in contrast, H3K9me3 status on promoters of Bax and Puma remained unchanged. Therefore, SETDB1 was responsible for regulating the transcription activity of genes in the apoptotic pathway at least in part through modulating H3K9me3. This study replenishes the research on the epigenetic regulation of SSC survival, and provides a new insight for the future study of epigenetic regulation of spermatogenesis. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. Effects of antioxidants, catalase and α-tocopherol on cell viability and oxidative stress variables in frozen-thawed mice spermatogonial stem cells.

    Science.gov (United States)

    Aliakbari, Freshte; Sedighi Gilani, Mohamad Ali; Yazdekhasti, Hossein; Koruji, Morteza; Asgari, Hamid Reza; Baazm, Maryam; Izadyar, Fariborz; Kharrazi Nejad, Ebrahim; Khanezad, Maryam; Abbasi, Mehdi

    2017-02-01

    Cryopreservation of spermatogonial stem cells is considered as a useful procedure for preserving fertility in children with testis cancer. SSCs were isolated from testes mice, and then antioxidant was added to the freezing medium. The Bax expression level in antioxidant groups was significantly (P ≤ 0.05) lower than the control group and a significant rise of Bcl2 expression was detected in the antioxidant groups. ROS production with antioxidant was significantly lower compared with the control group. Cryopreservation with the addition of the antioxidants can help increase the number of SSCs and improve the quality and viability of these cells after cryopreservation.

  2. Somatic ACE regulates self-renewal of mouse spermatogonial stem cells via the MAPK signaling pathway.

    Science.gov (United States)

    Gao, Tingting; Zhao, Xin; Liu, Chenchen; Shao, Binbin; Zhang, Xi; Li, Kai; Cai, Jinyang; Wang, Su; Huang, Xiaoyan

    2018-05-24

    Spermatogonial stem cell (SSC) self-renewal is an indispensable part of spermatogenesis. Angiotensin I-converting enzyme (ACE) is a zinc dipeptidyl carboxypeptidase that plays a critical role in regulation of the renin-angiotensin system. Here, we used RT-PCR and Western blot analysis to confirm that somatic ACE (sACE) but not testicular ACE (tACE) is highly expressed in mouse testis before postpartum day 7 and in cultured SSCs. Our results revealed that sACE is located on the membrane of SSCs. Treating cultured SSCs with the ACE competitive inhibitor captopril was found to inhibit sACE activity, and significantly reduced the proliferation rate of SSCs. Microarray analysis identified 651 genes with significant differential expression. KEGG pathway analysis showed that these differentially expressed genes are mainly involved in the mitogen-activated protein kinase (MAPK) signaling pathway and cell cycle. sACE was found to play an important role in SSC self-renewal via the regulation of MAPK-dependent cell proliferation.

  3. An attempt to distinguish a modified genetic response of the mouse testis to X-ray exposure by the action of a spermatogonial chalone

    International Nuclear Information System (INIS)

    Cattanach, B.M.; Jones, J.T.; Andrews, S.J.; Crocker, M.

    1979-01-01

    The results of an experiment designed to distinguish whether the action of a spermatogonial chalone in the mouse testis could modify the genetic response of a depleted stem spermatogonial population to X-radiation are reported. The results are consistent with the view that the stem cell population of the depleted adult testis a few days after damage closely approximates that of the early post-natal or immature animal, do not provide any indication that the testis extract in any way influence the response of the depleted testis to the 500-rad challenging dose. The yield of genetic damage was almost identical to that in the two control groups and the sterile period and testis weight data provided little reason to suspect that the amount of spermatogonial killing was altered. (Auth.)

  4. Indirect effects of Wnt3a/β-catenin signalling support mouse spermatogonial stem cells in vitro.

    Directory of Open Access Journals (Sweden)

    Jonathan R Yeh

    Full Text Available Proper regulation of spermatogonial stem cells (SSCs is crucial for sustaining steady-state spermatogenesis. Previous work has identified several paracrine factors involved in this regulation, in particular, glial cell line-derived neurotrophic factor and fibroblast growth factor 2, which promote long-term SSC self-renewal. Using a SSC culture system, we have recently reported that Wnt5a promotes SSC self-renewal through a β-catenin-independent Wnt mechanism whereas the β-catenin-dependent Wnt pathway is not active in SSCs. In contrast, another study has reported that Wnt3a promotes SSC self-renewal through the β-catenin-dependent pathway, as it can stimulate the proliferation of a spermatogonia cell line. To reconcile these two contradictory reports, we assessed Wnt3a effects on SSCs and progenitor cells, rather than a cell line, in vitro. We observed that Wnt3a induced β-catenin-dependent signalling in a large subset of germ cells and increased SSC numbers. However, further investigation revealed that cell populations with greater β-catenin-signalling activity contained fewer SSCs. The increased maintenance of SSCs by Wnt3a coincided with more active cell cycling and the formation of germ cell aggregates, or communities, under feeder-free conditions. Therefore, the results of this study suggest that Wnt3a selectively stimulates proliferation of progenitors that are committed to differentiation or are in the process of exiting the SSC state, leading to enhanced formation of germ cell communities, which indirectly support SSCs and act as an in vitro niche.

  5. Porcine spermatogonial stem cells self-renew effectively in a three dimensional culture microenvironment.

    Science.gov (United States)

    Park, Ji Eun; Park, Min Hee; Kim, Min Seong; Park, Yeo Reum; Yun, Jung Im; Cheong, Hee Tae; Kim, Minseok; Choi, Jung Hoon; Lee, Eunsong; Lee, Seung Tae

    2017-12-01

    Generally, self-renewal of spermatogonial stem cells (SSCs) is maintained in vivo in a three-dimensional (3D) microenvironment consisting of the seminiferous tubule basement membrane, indicating the importance of the 3D microenvironment for in vitro culture of SSCs. Here, we report a 3D culture microenvironment that effectively maintains porcine SSC self-renewal during culture. Porcine SSCs were cultured in an agarose-based 3D hydrogel and in 2D culture plates either with or without feeder cells. Subsequently, the effects of 3D culture on the maintenance of undifferentiated SSCs were identified by analyzing cell colony formation and morphology, AP activity, and transcriptional and translational regulation of self-renewal-related genes and the effects on proliferation by analyzing cell viability and single cell-derived colony number. The 3D culture microenvironment constructed using a 0.2% (w/v) agarose-based 3D hydrogel showed the strongest maintenance of porcine SSC self-renewal and induced significant improvements in proliferation compared with 2D culture microenvironments. These results demonstrate that self-renewal of porcine SSCs can be maintained more effectively in a 3D than in a 2D culture microenvironment. Moreover, this will play a significant role in developing novel culture systems for SSCs derived from diverse species in the future, which will contribute to SSC-related research. © 2017 International Federation for Cell Biology.

  6. Evidence for the re-establishment of a heterogeneity in radiosensitivity among spermatogonial stem cells repopulating the mouse testis following depletion by X-rays

    International Nuclear Information System (INIS)

    Cattanach, B.M.; Barlow, J.H.

    1984-01-01

    Earlier studies have shown that the spermatogonial stem cells of the mouse testis recovering from previous radiation or chemical mutagen exposure give subnormal yields of genetic damage with subsequent X-irradiation. This response has been investigated further: (a) with a high, 9-Gy X-ray dose given 4, 12 or 21 days after a 1-Gy conditioning dose and (b) with a 1 + 7-Gy, 24-h fractionation regime given 4 or 14 days after a 1-Gy conditioning dose. The results of the experiments suggest that a heterogeneity in radiosensitivity, such as exists in unirradiated stem cell populations and absent 24-48 h after radiation depletion, is quickly re-established among the stem cells repopulating the testis. And that the newly established heterogeneity is removed by the second 1-Gy conditioning dose. With longer intervals between treatments, genetic yields consistent with additivity were obtained in Expt. 1; less clear results were obtained in Expt. 2. Comparison with earlier data generally suggested that the duration of the repopulating period is dose-dependent. In a third experiment evidence was obtained that genetic damage induced by X-irradiation can be reduced by a subsequent treatment with triethylenemelamine (TEM) during the repopulating phase. This confirmed an earlier finding. Such an interaction could not be demonstrated with two X-ray treatments. An explanation for the X-ray/TEM interaction is offered. (Auth.)

  7. MicroRNA-10b regulates the renewal of spermatogonial stem cells through Kruppel-like factor 4.

    Science.gov (United States)

    Li, Jiang; Liu, Xiang; Hu, Xiaopeng; Tian, Geng G; Ma, Wenzhi; Pei, Xiuying; Wang, Yanrong; Wu, Ji

    2017-04-01

    MicroRNAs (miRs) are functionally important in spermatogenesis, which is the self-renewal or differentiation of spermatogonial stem cells (SSCs). Here, we report a novel role for miR-10b in regulating the self-renewal of mouse SSCs. We showed that miR-10b was highly expressed in mouse SSCs in vitro and enhanced SSC proliferation. Knockdown of miR-10b significantly increased the apoptosis of SSCs compared with controls. Kruppel-like factor 4 was found to be a target gene of miR-10b in the enhancement of SSC proliferation. These findings further our understanding of the self-renewal and differentiation of SSCs and provide a basis for the diagnosis, treatment, and prevention of male infertility. Copyright © 2017 John Wiley & Sons, Ltd.

  8. Glial cell line-derived neurotrophic factor and endothelial cells promote self-renewal of rabbit germ cells with spermatogonial stem cell properties.

    Science.gov (United States)

    Kubota, Hiroshi; Wu, Xin; Goodyear, Shaun M; Avarbock, Mary R; Brinster, Ralph L

    2011-08-01

    Previous studies suggest that exogenous factors crucial for spermatogonial stem cell (SSC) self-renewal are conserved among several mammalian species. Since glial cell line-derived neurotrophic factor (GDNF) and fibroblast growth factor 2 (FGF2) are critical for rodent SSC self-renewal, we hypothesized that they might promote self-renewal of nonrodent SSCs. Therefore, we cultured testicular germ cells from prepubertal rabbits in the presence of GDNF and FGF2 and found they proliferated indefinitely as cellular clumps that displayed characteristics previously identified for rodent SSCs. The rabbit germ cells could not be maintained on mouse embryonic fibroblast (STO) feeders that support rodent SSC self-renewal in vitro but were rather supported on mouse yolk sac-derived endothelial cell (C166) feeder layers. Proliferation of rabbit germ cells was dependent on GDNF. Of critical importance was that clump-forming rabbit germ cells colonized seminiferous tubules of immunodeficient mice, proliferated for at least 6 mo, while retaining an SSC phenotype in the testes of recipient mice, indicating that they were rabbit SSCs. This study demonstrates that GDNF is a mitogenic factor promoting self-renewal that is conserved between rodent and rabbit SSCs; with an evolutionary separation of ∼ 60 million years. These findings provide a foundation to study the mechanisms governing SSC self-renewal in nonrodent species.

  9. Generation of antiviral transgenic chicken using spermatogonial ...

    African Journals Online (AJOL)

    This study was conducted in order to generate anti-viral transgenic chickens through transfected spermatogonial stem cell with fusion gene EGFP-MMx. After injecting fusion gene EGFP-MMx into testes, tissues frozen section, polymerase chain reaction (PCR) and dot blot of testes was performed at 30, 40, 50, 60, 70 and 80 ...

  10. In search of an improved injection technique for the clinical application of spermatogonial stem cell transplantation.

    Science.gov (United States)

    Faes, Katrien; Lahoutte, Tony; Hoorens, Anne; Tournaye, Herman; Goossens, Ellen

    2017-03-01

    When fertility is impaired by anticancer treatment, spermatogonial stem cell transplantation (SSCT) could be used as a fertility restoration technique later on in life. Previously, we have demonstrated that a testicular cell suspension could be injected into a human cadaver testis, however, leakage to the interstitium was observed. In this study, injection of mouse testicular cells at an injection height of 50 cm (hydrostatic pressure) or via an automated injection pump (1400 µl, 2600 µl and 3000 µl) was evaluated. Significant difference in the filled radioactive volume was reached between the group in which 1400 µl was injected with an infusion pump and the groups in which 2600 µl (P = 0.019) or 3000 µl (P = 0.010) was injected. In all experimental groups green fluorescent protein positive (GFP + ) cells were observed in the seminiferous tubules. In conclusion, a lower injection height did not resolve the leakage of the injected cells to the interstitium. Using the infusion pump resulted in more efficient filling of the seminiferous tubules with lower interexperimental variability. Although leakage to the interstitium was still observed, with further optimisation, the use of an infusion pump for clinical application is advantageous. Copyright © 2016 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.

  11. Glial cell line-derived neurotrophic factor in combination with insulin-like growth factor 1 and basic fibroblast growth factor promote in vitro culture of goat spermatogonial stem cells.

    Science.gov (United States)

    Bahadorani, M; Hosseini, S M; Abedi, P; Abbasi, H; Nasr-Esfahani, M H

    2015-01-01

    Growth factors are increasingly considered as important regulators of spermatogonial stem cells (SSCs). This study investigated the effects of various growth factors (GDNF, IGF1, bFGF, EGF and GFRalpha-1) on purification and colonization of undifferentiated goat SSCs under in vitro and in vivo conditions. Irrespective of the culture condition used, the first signs of developing colonies were observed from day 4 of culture onwards. The number of colonies developed in GDNF + IGF1 + bFGF culture condition was significantly higher than the other groups (p culture condition was significantly higher than the other groups (p cells (vimentin, alpha-inhibin and α-SMA) and spermatogonial cells (PLZF, THY 1, VASA, alpha-1 integrin, bet-1 integrin and DBA) revealed that both cell types existed in developing colonies, irrespective of the culture condition used. Even though, the relative abundance of VASA, FGFR3, OCT4, PLZF, BCL6B and THY1 transcription factors in GDNF + IGF1 + bFGF treatment group was significantly higher than the other groups (p culture condition could colonize within the seminiferous tubules of the germ-cell depleted recipient mice following xenotransplantation. Obtained results demonstrated that combination of GDNF with IGF1 and bFGF promote in vitro culture of goat SSCs while precludes uncontrolled proliferation of somatic cells.

  12. The interaction between Sertoli cells and luekemia inhibitory factor on the propagation and differentiation of spermatogonial stem cells in vitro.

    Science.gov (United States)

    Rastegar, Tayebeh; Habibi Roudkenar, Mehryar; Parvari, Soraya; Baazm, Maryam

    2015-11-01

    Sertoli cells play a pivotal role in creating microenvironments essential for spermatogonial stem cells (SSCs) self-renewal and commitment to differentiation. Maintenance of SSCs and or induction of in vitro spermiogenesis may provide a therapeutic strategy to treat male infertility. This study investigated the role of luekemia inhibitory factor (LIF) on the propagation of SSCs and both functions of Sertoli cells on the proliferation and differentiation of these cells. SSCs were sorted from the testes of adult male mice by magnetic activated cell sorting and thymus cell antigen 1 antibody. On the other hand, isolated Sertoli cells were enriched using lectin coated plates. SSCs were cultured on Sertoli cells for 7 days in the absence or presence of LIF. The effects of these conditions were evaluated by microscopy and expression of meiotic and post meiotic transcripts by reverse transcriptase polymerase chain reaction. Our data showed that SSCs co-cultured with Sertoli cells in the presence of LIF formed colonies on top of the Sertoli cells. These colonies had alkaline phosphatesase activity and expressed SSCs specific genes. SSCs were enjoyed limited development after the mere removal of LIF, and exhibiting expression of meiotic and postmeiotic transcript and loss of SSCs specific gene expression (p< 0.05). Our findings represent co-culture of SSCs with Sertoli cells provides conditions that may allow efficient proliferation and differentiation of SSCs for male infertility treatment.

  13. The interaction between Sertoli cells and luekemia inhibitory factor on the propagation and differentiation of spermatogonial stem cells in vitro

    Directory of Open Access Journals (Sweden)

    Tayebeh Rastegar

    2015-11-01

    Full Text Available Background: Sertoli cells play a pivotal role in creating microenvironments essential for spermatogonial stem cells (SSCs self-renewal and commitment to differentiation. Maintenance of SSCs and or induction of in vitro spermiogenesis may provide a therapeutic strategy to treat male infertility. Objective: This study investigated the role of luekemia inhibitory factor (LIF on the propagation of SSCs and both functions of Sertoli cells on the proliferation and differentiation of these cells. Materials and Methods: SSCs were sorted from the testes of adult male mice by magnetic activated cell sorting and thymus cell antigen 1 antibody. On the other hand, isolated Sertoli cells were enriched using lectin coated plates. SSCs were cultured on Sertoli cells for 7 days in the absence or presence of LIF. The effects of these conditions were evaluated by microscopy and expression of meiotic and post meiotic transcripts by reverse transcriptase polymerase chain reaction. Results: Our data showed that SSCs co-cultured with Sertoli cells in the presence of LIF formed colonies on top of the Sertoli cells. These colonies had alkaline phosphatesase activity and expressed SSCs specific genes. SSCs were enjoyed limited development after the mere removal of LIF, and exhibiting expression of meiotic and postmeiotic transcript and loss of SSCs specific gene expression (p< 0.05. Conclusion: Our findings represent co-culture of SSCs with Sertoli cells provides conditions that may allow efficient proliferation and differentiation of SSCs for male infertility treatment.

  14. THE GERMLINE STEM CELL NICHE UNIT IN MAMMALIAN TESTES

    Science.gov (United States)

    Oatley, Jon M.; Brinster, Ralph L.

    2014-01-01

    This review addresses current understanding of the germline stem cell niche unit in mammalian testes. Spermatogenesis is a classic model of tissue-specific stem cell function relying on self-renewal and differentiation of spermatogonial stem cells (SSCs). These fate decisions are influenced by a niche microenvironment composed of a growth factor milieu that is provided by several testis somatic support cell populations. Investigations over the last two decades have identified key determinants of the SSC niche including cytokines that regulate SSC functions and support cells providing these factors, adhesion molecules that influence SSC homing, and developmental heterogeneity of the niche during postnatal aging. Emerging evidence suggests that Sertoli cells are a key support cell population influencing the formation and function of niches by secreting soluble factors and possibly orchestrating contributions of other support cells. Investigations with mice have shown that niche influence on SSC proliferation differs during early postnatal development and adulthood. Moreover, there is mounting evidence of an age-related decline in niche function, which is likely influenced by systemic factors. Defining the attributes of stem cell niches is key to developing methods to utilize these cells for regenerative medicine. The SSC population and associated niche comprise a valuable model system for study that provides fundamental knowledge about the biology of tissue-specific stem cells and their capacity to sustain homeostasis of regenerating tissue lineages. While the stem cell is essential for maintenance of all self-renewing tissues and has received considerable attention, the role of niche cells is at least as important and may prove to be more receptive to modification in regenerative medicine. PMID:22535892

  15. Juvenile spermatogonial depletion (jsd): a genetic defect of germ cell proliferation of male mice.

    Science.gov (United States)

    Beamer, W G; Cunliffe-Beamer, T L; Shultz, K L; Langley, S H; Roderick, T H

    1988-05-01

    Adult C57BL/6J male mice homozygous for the mutant gene, juvenile spermatogonial depletion (jsd/jsd), show azoosper4ia and testes reduced to one-third normal size, but are otherwise phenotypically normal. In contrast, adult jsd/jsd females are fully fertile. This feature facilitated mapping the jsd gene to the centromeric end of chromosome 1; the gene order is jsd-Isocitrate dehydrogenase-1 (Idh-1)-Peptidase-3 (Pep-3). Analysis of testicular histology from jsd/jsd mice aged 3-10 wk revealed that these mutant mice experience one wave of spermatogenesis, but fail to continue mitotic proliferation of type A spermatogonial cells at the basement membrane. As a consequence, histological sections of testes from mutant mice aged 8-52 wk showed tubules populated by modest numbers of Sertoli cells, with only an occasional spermatogonial cell. Some sperm with normal morphology and motility were observed in epididymides of 6.5- but not in 8-wk or older mutants. Treatment with retinol failed to alter the loss of spermatogenesis in jsd/jsd mice. Analyses of serum hormones of jsd/jsd males showed that testosterone levels were normal at all ages--a finding corroborated by normal seminal vesicle and vas deferens weights, whereas serum follicle-stimulating hormone levels were significantly elevated in mutant mice from 4 to 20 wk of age. We hypothesize the jsd/jsd male may be deficient in proliferative signals from Sertoli cells that are needed for spermatogenesis.

  16. Gene expression heterogeneities in embryonic stem cell populations

    DEFF Research Database (Denmark)

    Martinez Arias, Alfonso; Brickman, Joshua M

    2011-01-01

    Stem and progenitor cells are populations of cells that retain the capacity to populate specific lineages and to transit this capacity through cell division. However, attempts to define markers for stem cells have met with limited success. Here we consider whether this limited success reflects...... an intrinsic requirement for heterogeneity with stem cell populations. We focus on Embryonic Stem (ES) cells, in vitro derived cell lines from the early embryo that are considered both pluripotent (able to generate all the lineages of the future embryo) and indefinitely self renewing. We examine the relevance...... of recently reported heterogeneities in ES cells and whether these heterogeneities themselves are inherent requirements of functional potency and self renewal....

  17. Pluripotent stem cells and reprogrammed cells in farm animals.

    Science.gov (United States)

    Nowak-Imialek, Monika; Kues, Wilfried; Carnwath, Joseph W; Niemann, Heiner

    2011-08-01

    Pluripotent cells are unique because of their ability to differentiate into the cell lineages forming the entire organism. True pluripotent stem cells with germ line contribution have been reported for mice and rats. Human pluripotent cells share numerous features of pluripotentiality, but confirmation of their in vivo capacity for germ line contribution is impossible due to ethical and legal restrictions. Progress toward derivation of embryonic stem cells from domestic species has been made, but the derived cells were not able to produce germ line chimeras and thus are termed embryonic stem-like cells. However, domestic animals, in particular the domestic pig (Sus scrofa), are excellent large animals models, in which the clinical potential of stem cell therapies can be studied. Reprogramming technologies for somatic cells, including somatic cell nuclear transfer, cell fusion, in vitro culture in the presence of cell extracts, in vitro conversion of adult unipotent spermatogonial stem cells into germ line derived pluripotent stem cells, and transduction with reprogramming factors have been developed with the goal of obtaining pluripotent, germ line competent stem cells from domestic animals. This review summarizes the present state of the art in the derivation and maintenance of pluripotent stem cells in domestic animals.

  18. The Role of Integrin α6 (CD49f) in Stem Cells: More than a Conserved Biomarker.

    Science.gov (United States)

    Krebsbach, Paul H; Villa-Diaz, Luis G

    2017-08-01

    Stem cells have the capacity for self-renewal and differentiation into specialized cells that form and repopulated all tissues and organs, from conception to adult life. Depending on their capacity for differentiation, stem cells are classified as totipotent (ie, zygote), pluripotent (ie, embryonic stem cells), multipotent (ie, neuronal stem cells, hematopoietic stem cells, epithelial stem cells, etc.), and unipotent (ie, spermatogonial stem cells). Adult or tissue-specific stem cells reside in specific niches located in, or nearby, their organ or tissue of origin. There, they have microenvironmental support to remain quiescent, to proliferate as undifferentiated cells (self-renewal), and to differentiate into progenitors or terminally differentiated cells that migrate from the niche to perform specialized functions. The presence of proteins at the cell surface is often used to identify, classify, and isolate stem cells. Among the diverse groups of cell surface proteins used for these purposes, integrin α6, also known as CD49f, may be the only biomarker commonly found in more than 30 different populations of stem cells, including some cancer stem cells. This broad expression among stem cell populations indicates that integrin α6 may play an important and conserved role in stem cell biology, which is reaffirmed by recent demonstrations of its role maintaining self-renewal of pluripotent stem cells and breast and glioblastoma cancer stem cells. Therefore, this review intends to highlight and synthesize new findings on the importance of integrin α6 in stem cell biology.

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

    Science.gov (United States)

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

    2010-01-01

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

  20. Very small embryonic-like stem cells: implications in reproductive biology.

    Science.gov (United States)

    Bhartiya, Deepa; Unni, Sreepoorna; Parte, Seema; Anand, Sandhya

    2013-01-01

    The most primitive germ cells in adult mammalian testis are the spermatogonial stem cells (SSCs) whereas primordial follicles (PFs) are considered the fundamental functional unit in ovary. However, this central dogma has recently been modified with the identification of a novel population of very small embryonic-like stem cells (VSELs) in the adult mammalian gonads. These stem cells are more primitive to SSCs and are also implicated during postnatal ovarian neo-oogenesis and primordial follicle assembly. VSELs are pluripotent in nature and characterized by nuclear Oct-4A, cell surface SSEA-4, and other pluripotent markers like Nanog, Sox2, and TERT. VSELs are considered to be the descendants of epiblast stem cells and possibly the primordial germ cells that persist into adulthood and undergo asymmetric cell division to replenish the gonadal germ cells throughout life. Elucidation of their role during infertility, endometrial repair, superovulation, and pathogenesis of various reproductive diseases like PCOS, endometriosis, cancer, and so on needs to be addressed. Hence, a detailed review of current understanding of VSEL biology is pertinent, which will hopefully open up new avenues for research to better understand various reproductive processes and cancers. It will also be relevant for future regenerative medicine, translational research, and clinical applications in human reproduction.

  1. Very Small Embryonic-Like Stem Cells: Implications in Reproductive Biology

    Directory of Open Access Journals (Sweden)

    Deepa Bhartiya

    2013-01-01

    Full Text Available The most primitive germ cells in adult mammalian testis are the spermatogonial stem cells (SSCs whereas primordial follicles (PFs are considered the fundamental functional unit in ovary. However, this central dogma has recently been modified with the identification of a novel population of very small embryonic-like stem cells (VSELs in the adult mammalian gonads. These stem cells are more primitive to SSCs and are also implicated during postnatal ovarian neo-oogenesis and primordial follicle assembly. VSELs are pluripotent in nature and characterized by nuclear Oct-4A, cell surface SSEA-4, and other pluripotent markers like Nanog, Sox2, and TERT. VSELs are considered to be the descendants of epiblast stem cells and possibly the primordial germ cells that persist into adulthood and undergo asymmetric cell division to replenish the gonadal germ cells throughout life. Elucidation of their role during infertility, endometrial repair, superovulation, and pathogenesis of various reproductive diseases like PCOS, endometriosis, cancer, and so on needs to be addressed. Hence, a detailed review of current understanding of VSEL biology is pertinent, which will hopefully open up new avenues for research to better understand various reproductive processes and cancers. It will also be relevant for future regenerative medicine, translational research, and clinical applications in human reproduction.

  2. Concise Review: Stem Cell Population Biology: Insights from Hematopoiesis.

    Science.gov (United States)

    MacLean, Adam L; Lo Celso, Cristina; Stumpf, Michael P H

    2017-01-01

    Stem cells are fundamental to human life and offer great therapeutic potential, yet their biology remains incompletely-or in cases even poorly-understood. The field of stem cell biology has grown substantially in recent years due to a combination of experimental and theoretical contributions: the experimental branch of this work provides data in an ever-increasing number of dimensions, while the theoretical branch seeks to determine suitable models of the fundamental stem cell processes that these data describe. The application of population dynamics to biology is amongst the oldest applications of mathematics to biology, and the population dynamics perspective continues to offer much today. Here we describe the impact that such a perspective has made in the field of stem cell biology. Using hematopoietic stem cells as our model system, we discuss the approaches that have been used to study their key properties, such as capacity for self-renewal, differentiation, and cell fate lineage choice. We will also discuss the relevance of population dynamics in models of stem cells and cancer, where competition naturally emerges as an influential factor on the temporal evolution of cell populations. Stem Cells 2017;35:80-88. © 2016 AlphaMed Press.

  3. Controlling the diversity of cell populations in a stem cell culture

    NARCIS (Netherlands)

    Heo, Inha; Clevers, Hans

    2015-01-01

    Culturing intestinal stem cells into 3D organoids results in heterogeneous cell populations, reflecting the in vivo cell type diversity. In a recent paper published in Nature, Wang et al. established a culture condition for a highly homogeneous population of intestinal stem cells.

  4. Radiobiological properties of spermatogonial stem cells in C3H/101 hybrid mice and evaluation of the model for induction of genetic damage in spermatogonial stem cells

    International Nuclear Information System (INIS)

    De Rooij, V.

    1993-01-01

    C3H/101 (3H1) hybrid mice are studied, in order to find answers to the following questions: What are the D 0 values for killing of proliferating and quiescent stem cells by X-irradiation in 3H1 mice; How many stem cells are present per 3H1 testis and what is the density of these cells during the epithelial cycle; What are the approximate numbers of proliferating and quiescent stem cells in a 3H1 mouse testis. (R.P.) 5 figs

  5. Cell cycle of spermatogonial colony forming stem cells in the CBA mouse after neutron irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Bootsma, A.L. (Rijksuniversiteit Utrecht (Netherlands). Academisch Ziekenhuis); Davids, J.A.G. (Netherlands Energy Research Foundation, Petten (Netherlands))

    1988-03-01

    In the CBA mouse testis, about 10% of the stem cell population is highly resistant to neutron irradiation (D/sub 0/, 0.75 Gy). Following a dose of 1.50 Gy these cells rapidly increase their sensitivity towards a second neutron dose and progress fairly synchronously through their first post-irradiation cell cycle. From experiments in which neutron irradiation was combined with hydroxyurea, it appeared that in this cycle the S-phase is less radiosensitive (D/sub 0/, 0.43 Gy) than the other phases of the cell cycle (D/sub 0/, 0.25 Gy). From experiments in which hydroxyurea was injected twice after irradiation, the speed of inflow of cells in S and the duration of S and the cell cycle could be calculated. Between 32 and 36 hr after irradiation cells start to enter the S-phase at a speed of 30% of the population every 12 hr. At 60 hr 50% of the population has already passed the S-phase while 30% is still in S. The data point to a cell cycle time of about 36 hr, while the S-phase lasts 12 hr at the most. (author).

  6. Deconstructing stem cell population heterogeneity: Single-cell analysis and modeling approaches

    Science.gov (United States)

    Wu, Jincheng; Tzanakakis, Emmanuel S.

    2014-01-01

    Isogenic stem cell populations display cell-to-cell variations in a multitude of attributes including gene or protein expression, epigenetic state, morphology, proliferation and proclivity for differentiation. The origins of the observed heterogeneity and its roles in the maintenance of pluripotency and the lineage specification of stem cells remain unclear. Addressing pertinent questions will require the employment of single-cell analysis methods as traditional cell biochemical and biomolecular assays yield mostly population-average data. In addition to time-lapse microscopy and flow cytometry, recent advances in single-cell genomic, transcriptomic and proteomic profiling are reviewed. The application of multiple displacement amplification, next generation sequencing, mass cytometry and spectrometry to stem cell systems is expected to provide a wealth of information affording unprecedented levels of multiparametric characterization of cell ensembles under defined conditions promoting pluripotency or commitment. Establishing connections between single-cell analysis information and the observed phenotypes will also require suitable mathematical models. Stem cell self-renewal and differentiation are orchestrated by the coordinated regulation of subcellular, intercellular and niche-wide processes spanning multiple time scales. Here, we discuss different modeling approaches and challenges arising from their application to stem cell populations. Integrating single-cell analysis with computational methods will fill gaps in our knowledge about the functions of heterogeneity in stem cell physiology. This combination will also aid the rational design of efficient differentiation and reprogramming strategies as well as bioprocesses for the production of clinically valuable stem cell derivatives. PMID:24035899

  7. Novel Action of FSH on Stem Cells in Adult Mammalian Ovary Induces Postnatal Oogenesis and Primordial Follicle Assembly

    Directory of Open Access Journals (Sweden)

    Deepa Bhartiya

    2016-01-01

    Full Text Available Adult mammalian ovary has been under the scanner for more than a decade now since it was proposed to harbor stem cells that undergo postnatal oogenesis during reproductive period like spermatogenesis in testis. Stem cells are located in the ovary surface epithelium and exist in adult and menopausal ovary as well as in ovary with premature failure. Stem cells comprise two distinct populations including spherical, very small embryonic-like stem cells (VSELs which express nuclear OCT-4 and other pluripotent and primordial germ cells specific markers and slightly bigger ovarian germ stem cells (OGSCs with cytoplasmic OCT-4 which are equivalent to spermatogonial stem cells in the testes. These stem cells have the ability to spontaneously differentiate into oocyte-like structures in vitro and on exposure to a younger healthy niche. Bone marrow may be an alternative source of these stem cells. The stem cells express FSHR and respond to FSH by undergoing self-renewal, clonal expansion, and initiating neo-oogenesis and primordial follicle assembly. VSELs are relatively quiescent and were recently reported to survive chemotherapy and initiate oogenesis in mice when exposed to FSH. This emerging understanding and further research in the field will help evolving novel strategies to manage ovarian pathologies and also towards oncofertility.

  8. Identification of CHD1L as an Important Regulator for Spermatogonial Stem Cell Survival and Self-Renewal

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    Shan-Shan Liu

    2016-01-01

    Full Text Available Chromodomain helicase/ATPase DNA binding protein 1-like gene (Chd1l participates in chromatin-dependent processes, including transcriptional activation and DNA repair. In this study, we have found for the first time that Chd1l is mainly expressed in the testicular tissues of prepubertal and adult mice and colocalized with PLZF, OCT4, and GFRα1 in the neonatal mouse testis and THY1+ undifferentiated spermatogonia or spermatogonial stem cells (SSCs. Knockdown of endogenous Chd1l in cultured mouse undifferentiated SSCs inhibited the expression levels of Oct4, Plzf, Gfrα1, and Pcna genes, suppressed SSC colony formation, and reduced BrdU incorporation, while increasing SSC apoptosis. Moreover, the Chd1l gene expression is activated by GDNF in the cultured mouse SSCs, and the GDNF signaling pathway was modulated by endogenous levels of Chd1l; as demonstrated by the gene expression levels of GDNF, inducible transcripts Etv5, Bcl6b, Pou3f, and Lhx1, but not that of GDNF-independent gene, Taf4b, were significantly downregulated by Chd1l knockdown in mouse SSCs. Taken together, this study provides the first evidence to support the notion that Chd1l is an intrinsic and novel regulator for SSC survival and self-renewal, and it exerts such regulation at least partially through a GDNF signaling pathway.

  9. Cellular evidence for selfish spermatogonial selection in aged human testes.

    Science.gov (United States)

    Maher, G J; Goriely, A; Wilkie, A O M

    2014-05-01

    Owing to a recent trend for delayed paternity, the genomic integrity of spermatozoa of older men has become a focus of increased interest. Older fathers are at higher risk for their children to be born with several monogenic conditions collectively termed paternal age effect (PAE) disorders, which include achondroplasia, Apert syndrome and Costello syndrome. These disorders are caused by specific mutations originating almost exclusively from the male germline, in genes encoding components of the tyrosine kinase receptor/RAS/MAPK signalling pathway. These particular mutations, occurring randomly during mitotic divisions of spermatogonial stem cells (SSCs), are predicted to confer a selective/growth advantage on the mutant SSC. This selective advantage leads to a clonal expansion of the mutant cells over time, which generates mutant spermatozoa at levels significantly above the background mutation rate. This phenomenon, termed selfish spermatogonial selection, is likely to occur in all men. In rare cases, probably because of additional mutational events, selfish spermatogonial selection may lead to spermatocytic seminoma. The studies that initially predicted the clonal nature of selfish spermatogonial selection were based on DNA analysis, rather than the visualization of mutant clones in intact testes. In a recent study that aimed to identify these clones directly, we stained serial sections of fixed testes for expression of melanoma antigen family A4 (MAGEA4), a marker of spermatogonia. A subset of seminiferous tubules with an appearance and distribution compatible with the predicted mutant clones were identified. In these tubules, termed 'immunopositive tubules', there is an increased density of spermatogonia positive for markers related to selfish selection (FGFR3) and SSC self-renewal (phosphorylated AKT). Here we detail the properties of the immunopositive tubules and how they relate to the predicted mutant clones, as well as discussing the utility of

  10. Generation of male differentiated germ cells from various types of stem cells.

    Science.gov (United States)

    Hou, Jingmei; Yang, Shi; Yang, Hao; Liu, Yang; Liu, Yun; Hai, Yanan; Chen, Zheng; Guo, Ying; Gong, Yuehua; Gao, Wei-Qiang; Li, Zheng; He, Zuping

    2014-06-01

    Infertility is a major and largely incurable disease caused by disruption and loss of germ cells. It affects 10-15% of couples, and male factor accounts for half of the cases. To obtain human male germ cells 'especially functional spermatids' is essential for treating male infertility. Currently, much progress has been made on generating male germ cells, including spermatogonia, spermatocytes, and spermatids, from various types of stem cells. These germ cells can also be used in investigation of the pathology of male infertility. In this review, we focused on advances on obtaining male differentiated germ cells from different kinds of stem cells, with an emphasis on the embryonic stem (ES) cells, the induced pluripotent stem (iPS) cells, and spermatogonial stem cells (SSCs). We illustrated the generation of male differentiated germ cells from ES cells, iPS cells and SSCs, and we summarized the phenotype for these stem cells, spermatocytes and spermatids. Moreover, we address the differentiation potentials of ES cells, iPS cells and SSCs. We also highlight the advantages, disadvantages and concerns on derivation of the differentiated male germ cells from several types of stem cells. The ability of generating mature and functional male gametes from stem cells could enable us to understand the precise etiology of male infertility and offer an invaluable source of autologous male gametes for treating male infertility of azoospermia patients. © 2014 Society for Reproduction and Fertility.

  11. Stem cell-like differentiation potentials of endometrial side population cells as revealed by a newly developed in vivo endometrial stem cell assay.

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    Kaoru Miyazaki

    Full Text Available Endometrial stem/progenitor cells contribute to the cyclical regeneration of human endometrium throughout a woman's reproductive life. Although the candidate cell populations have been extensively studied, no consensus exists regarding which endometrial population represents the stem/progenitor cell fraction in terms of in vivo stem cell activity. We have previously reported that human endometrial side population cells (ESP, but not endometrial main population cells (EMP, exhibit stem cell-like properties, including in vivo reconstitution of endometrium-like tissues when xenotransplanted into immunodeficient mice. The reconstitution efficiency, however, was low presumably because ESP cells alone could not provide a sufficient microenvironment (niche to support their stem cell activity. The objective of this study was to establish a novel in vivo endometrial stem cell assay employing cell tracking and tissue reconstitution systems and to examine the stem cell properties of ESP through use of this assay.ESP and EMP cells isolated from whole endometrial cells were infected with lentivirus to express tandem Tomato (TdTom, a red fluorescent protein. They were mixed with unlabeled whole endometrial cells and then transplanted under the kidney capsule of ovariectomized immunodeficient mice. These mice were treated with estradiol and progesterone for eight weeks and nephrectomized. All of the grafts reconstituted endometrium-like tissues under the kidney capsules. Immunofluorescence revealed that TdTom-positive cells were significantly more abundant in the glandular, stromal, and endothelial cells of the reconstituted endometrium in mice transplanted with TdTom-labeled ESP cells than those with TdTom-labeled EMP cells.We have established a novel in vivo endometrial stem cell assay in which multi-potential differentiation can be identified through cell tracking during in vivo endometrial tissue reconstitution. Using this assay, we demonstrated that ESP

  12. A stem cell medium containing neural stimulating factor induces a pancreatic cancer stem-like cell-enriched population

    Science.gov (United States)

    WATANABE, YUSAKU; YOSHIMURA, KIYOSHI; YOSHIKAWA, KOICHI; TSUNEDOMI, RYOICHI; SHINDO, YOSHITARO; MATSUKUMA, SOU; MAEDA, NORIKO; KANEKIYO, SHINSUKE; SUZUKI, NOBUAKI; KURAMASU, ATSUO; SONODA, KOUHEI; TAMADA, KOJI; KOBAYASHI, SEI; SAYA, HIDEYUKI; HAZAMA, SHOICHI; OKA, MASAAKI

    2014-01-01

    Cancer stem cells (CSCs) have been studied for their self-renewal capacity and pluripotency, as well as their resistance to anticancer therapy and their ability to metastasize to distant organs. CSCs are difficult to study because their population is quite low in tumor specimens. To overcome this problem, we established a culture method to induce a pancreatic cancer stem-like cell (P-CSLC)-enriched population from human pancreatic cancer cell lines. Human pancreatic cancer cell lines established at our department were cultured in CSC-inducing media containing epidermal growth factor (EGF), basic fibroblast growth factor (bFGF), leukemia inhibitory factor (LIF), neural cell survivor factor-1 (NSF-1), and N-acetylcysteine. Sphere cells were obtained and then transferred to a laminin-coated dish and cultured for approximately two months. The surface markers, gene expression, aldehyde dehydrogenase (ALDH) activity, cell cycle, and tumorigenicity of these induced cells were examined for their stem cell-like characteristics. The population of these induced cells expanded within a few months. The ratio of CD24high, CD44high, epithelial specific antigen (ESA) high, and CD44variant (CD44v) high cells in the induced cells was greatly enriched. The induced cells stayed in the G0/G1 phase and demonstrated mesenchymal and stemness properties. The induced cells had high tumorigenic potential. Thus, we established a culture method to induce a P-CSLCenriched population from human pancreatic cancer cell lines. The CSLC population was enriched approximately 100-fold with this method. Our culture method may contribute to the precise analysis of CSCs and thus support the establishment of CSC-targeting therapy. PMID:25118635

  13. Cellular population dynamics control the robustness of the stem cell niche

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    Adam L. MacLean

    2015-11-01

    Full Text Available Within populations of cells, fate decisions are controlled by an indeterminate combination of cell-intrinsic and cell-extrinsic factors. In the case of stem cells, the stem cell niche is believed to maintain ‘stemness’ through communication and interactions between the stem cells and one or more other cell-types that contribute to the niche conditions. To investigate the robustness of cell fate decisions in the stem cell hierarchy and the role that the niche plays, we introduce simple mathematical models of stem and progenitor cells, their progeny and their interplay in the niche. These models capture the fundamental processes of proliferation and differentiation and allow us to consider alternative possibilities regarding how niche-mediated signalling feedback regulates the niche dynamics. Generalised stability analysis of these stem cell niche systems enables us to describe the stability properties of each model. We find that although the number of feasible states depends on the model, their probabilities of stability in general do not: stem cell–niche models are stable across a wide range of parameters. We demonstrate that niche-mediated feedback increases the number of stable steady states, and show how distinct cell states have distinct branching characteristics. The ecological feedback and interactions mediated by the stem cell niche thus lend (surprisingly high levels of robustness to the stem and progenitor cell population dynamics. Furthermore, cell–cell interactions are sufficient for populations of stem cells and their progeny to achieve stability and maintain homeostasis. We show that the robustness of the niche – and hence of the stem cell pool in the niche – depends only weakly, if at all, on the complexity of the niche make-up: simple as well as complicated niche systems are capable of supporting robust and stable stem cell dynamics.

  14. Low-dose ionizing irradiation triggers a 53BP1 response to DNA double strand breaks in mouse spermatogonial stem cells.

    Science.gov (United States)

    Le, Wei; Qi, Lixin; Li, Jiaxuan; Wu, DengIong; Xu, Jun; Zhang, Jinfu

    2016-01-01

    The present study aims to examine the effect of low-dose ionizing irradiation on DNA double strand breaks (DSB) in mouse spermatogonial stem cells (SSCs) and reveal the underlying pathways for the DNA repair for DSB in SSCs. Eighteen one-month-old mice were divided into 6 groups and sacrificed separately at 45 minutes, 2 hours, 24 hours, 48 hours, and 72 hours after 0.1Gy X-ray irradiation (mice without receiving ionizing irradiation served as control). After perfusion fixation, testes were removed, sectioned, and followed by staining of γH2AX, 53BP1, Caspase 3, and promyelocytic leukemia zinc-finger (PLZF) for analysis among the different groups. The staining was observed by immunofluorescence visualized by confocal laser scanning. After low-dose irradiation, only 53BP1, but not Caspase3 or γH2AX was upregulated in PLZF positive SSCs within 45 minutes. The expression level of 53BP1 gradually decreased 24 hours after irradiation. Moreover, low-dose irradiation had no effect on the cell number and apoptotic status of SSCs. However other spermatogenic cells highly expressed γH2AX shortly after irradiation which was dramatically reduced following the events of DNA repair. It appears that low-dose ionizing irradiation may cause the DNA DSB of mouse spermatogenic cells. 53BP1, but not γH2AX, is involved in the DNA repair for DSB in SSCs. Our data indicates that 53BP1 plays an important role in the pathophysiological repair of DNA DSB in SSCs. This may open a new avenue to understanding the mechanisms of DNA repair of SSCs and male infertility.

  15. SALL4 expression in gonocytes and spermatogonial clones of postnatal mouse testes.

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    Kathrin Gassei

    Full Text Available The spermatogenic lineage is established after birth when gonocytes migrate to the basement membrane of seminiferous tubules and give rise to spermatogonial stem cells (SSC. In adults, SSCs reside within the population of undifferentiated spermatogonia (A(undiff that expands clonally from single cells (A(single to form pairs (A(paired and chains of 4, 8 and 16 A(aligned spermatogonia. Although stem cell activity is thought to reside in the population of A(single spermatogonia, new research suggests that clone size alone does not define the stem cell pool. The mechanisms that regulate self-renewal and differentiation fate decisions are poorly understood due to limited availability of experimental tools that distinguish the products of those fate decisions. The pluripotency factor SALL4 (sal-like protein 4 is implicated in stem cell maintenance and patterning in many organs during embryonic development, but expression becomes restricted to the gonads after birth. We analyzed the expression of SALL4 in the mouse testis during the first weeks after birth and in adult seminiferous tubules. In newborn mice, the isoform SALL4B is expressed in quiescent gonocytes at postnatal day 0 (PND0 and SALL4A is upregulated at PND7 when gonocytes have colonized the basement membrane and given rise to spermatogonia. During steady-state spermatogenesis in adult testes, SALL4 expression overlapped substantially with PLZF and LIN28 in A(single, A(paired and A(aligned spermatogonia and therefore appears to be a marker of undifferentiated spermatogonia in mice. In contrast, co-expression of SALL4 with GFRα1 and cKIT identified distinct subpopulations of A(undiff in all clone sizes that might provide clues about SSC regulation. Collectively, these results indicate that 1 SALL4 isoforms are differentially expressed at the initiation of spermatogenesis, 2 SALL4 is expressed in undifferentiated spermatogonia in adult testes and 3 SALL4 co-staining with GFRα1 and c

  16. Recovery of the Erythropoietin-Sensitive Stem-Cell Population following Total-Body X-Irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Byron, J. W. [Paterson Laboratories, Christie Hospital and Holt Radium Institute, Manchester (United Kingdom)

    1968-08-15

    Erythropoietin acts upon haemopoietic stem cells to initiate their differentiation into the erythroid series. This effect may be used in polycythaemic mice to estimate changes in the erythropoietin-sensitive stem-cell population following total-body irradiation (TBR). Generally, single doses of erythropoietin, less than that needed for maximum stem-cell response, are used to estimate changes in the stem-cell population. The validity of results using this test is based upon accepting several assumptions regarding erythropoietin kinetics. These are: (a) the contribution of endogenous erythropoietin is always negligible; (b) the origin of the dose-response curve to erythropoietin alters only because of changes in stem-cell numbers; (c) the proportion of stem cells responding to a given concentration of erythropoietin is independent of stem-cell numbers; (d) the slope of the dose-response curve does not alter; and (e) competition between erythropoietin and other factors for the stem cells remains unchanged. The studies to be reported indicate that some of these assumptions m a y not always be valid. Following 150 rad TBR, changes in erythropoietin dose-response curves were not always due to changes in the size of the stem-cell population, but also due to changes in erythropoietin kinetics. Changes in erythropoietin kinetics could be corrected for by using doses of erythropoietin which at any particular time after TBR gave maximum stem-cell response; through full dose-response studies, the nature of changes in erythropoietin kinetics following TBR could be established. These studies appear to explain discrepancies in results obtained in different laboratories using the erythropoietin test. The effect of 150 rad TBR on the erythropoietin-sensitive stem-cell population is an initial depression within 30 min to 20% of normal followed by a second depression (post-irradiation dip) at about 12 h. Twenty-four hours after TBR there is a recovery to the initial depression. This

  17. Regulation of Injury-Induced Ovarian Regeneration by Activation of Oogonial Stem Cells.

    Science.gov (United States)

    Erler, Piril; Sweeney, Alexandra; Monaghan, James R

    2017-01-01

    Some animals have the ability to generate large numbers of oocytes throughout life. This raises the question whether persistent adult germline stem cell populations drive continuous oogenesis and whether they are capable of mounting a regenerative response after injury. Here we demonstrate the presence of adult oogonial stem cells (OSCs) in the adult axolotl salamander ovary and show that ovarian injury induces OSC activation and functional regeneration of the ovaries to reproductive capability. Cells that have morphological similarities to germ cells were identified in the developing and adult ovaries via histological analysis. Genes involved in germ cell maintenance including Vasa, Oct4, Sox2, Nanog, Bmp15, Piwil1, Piwil2, Dazl, and Lhx8 were expressed in the presumptive OSCs. Colocalization of Vasa protein with H3 mitotic marker showed that both oogonial and spermatogonial adult stem cells were mitotically active. Providing evidence of stemness and viability of adult OSCs, enhanced green fluorescent protein (EGFP) adult OSCs grafted into white juvenile host gonads gave rise to EGFP OSCs, and oocytes. Last, the axolotl ovaries completely regenerated after partial ovariectomy injury. During regeneration, OSC activation resulted in rapid differentiation into new oocytes, which was demonstrated by Vasa + /BrdU + coexpression. Furthermore, follicle cell proliferation promoted follicle maturation during ovarian regeneration. Overall, these results show that adult oogenesis occurs via proliferation of endogenous OSCs in a tetrapod and mediates ovarian regeneration. This study lays the foundations to elucidate mechanisms of ovarian regeneration that will assist regenerative medicine in treating premature ovarian failure and reduced fertility. Stem Cells 2017;35:236-247. © 2016 AlphaMed Press.

  18. In vitro expansion of the mammary stem/progenitor cell population by xanthosine treatment

    Directory of Open Access Journals (Sweden)

    Choudhary Ratan K

    2012-06-01

    Full Text Available Abstract Background Mammary stem cells are critical for growth and maintenance of the mammary gland and therefore are of considerable interest for improving productivity and efficiency of dairy animals. Xanthosine treatment has been demonstrated to promote expansion of putative mammary stem cells in vivo, and hepatic and hair follicle stem cells in vitro. In the latter, xanthosine promoted the symmetrical division of hepatic and hair follicle stem cells. The objective of this study was to determine if treating primary cultures of bovine mammary epithelial cells (MEC with xanthosine increases the stem/progenitor cell population by promoting symmetrical division of mammary stem cells. Results In vitro treatment with xanthosine increased the population of MEC during the exponential phase of cell growth, reducing the doubling time from 86 h in control cultures to 60 h in xanthosine-treated cultures. The bromodeoxyuridine (BrdU labeling index and the proportion of MEC in S-phase both were increased by xanthosine treatment, indicating that increased cell accretion was due to increased cell proliferation. Analysis of daughter-pairs indicated that xanthosine promoted a shift from asymmetric to symmetric cell division. Moreover, the 30 % increase in symmetric cell division was concomitant with an increase in the proportion of MEC that were positive for a putative stem cell marker (FNDC3B and a trend toward increased telomerase activity. These results suggest that xanthosine treatment in vitro can increase cell proliferation, promote symmetric cell division and enhance stem/progenitor cell activity. Conclusions Xanthosine treatment increased the proliferation rate of bovine MEC in vitro. This was likely to be mediated by an increase in the proportion of stem/progenitor cells in the MEC population due to promotion of symmetrical stem cell division by xanthosine.

  19. Generation, characterization and potential therapeutic applications of mature and functional hepatocytes from stem cells.

    Science.gov (United States)

    Zhang, Zhenzhen; Liu, Jianfang; Liu, Yang; Li, Zheng; Gao, Wei-Qiang; He, Zuping

    2013-02-01

    Liver cancer is the sixth most common tumor in the world and the majority of patients with this disease usually die within 1 year. The effective treatment for end-stage liver disease (also known as liver failure), including liver cancer or cirrhosis, is liver transplantation. However, there is a severe shortage of liver donors worldwide, which is the major handicap for the treatment of patients with liver failure. Scarcity of liver donors underscores the urgent need of using stem cell therapy to the end-stage liver disease. Notably, hepatocytes have recently been generated from hepatic and extra-hepatic stem cells. We have obtained mature and functional hepatocytes from rat hepatic stem cells. Here, we review the advancements on hepatic differentiation from various stem cells, including hepatic stem cells, embryonic stem cells, the induced pluripotent stem cells, hematopoietic stem cells, mesenchymal stem cells, and probably spermatogonial stem cells. The advantages, disadvantages, and concerns on differentiation of these stem cells into hepatic cells are highlighted. We further address the methodologies, phenotypes, and functional characterization on the differentiation of numerous stem cells into hepatic cells. Differentiation of stem cells into mature and functional hepatocytes, especially from an extra-hepatic stem cell source, would circumvent the scarcity of liver donors and human hepatocytes, and most importantly it would offer an ideal and promising source of hepatocytes for cell therapy and tissue engineering in treating liver disease. Copyright © 2012 Wiley Periodicals, Inc.

  20. Plasticity of male germline stem cells and their applications in reproductive and regenerative medicine

    Directory of Open Access Journals (Sweden)

    Zheng Chen

    2015-06-01

    Full Text Available Spermatogonial stem cells (SSCs, also known as male germline stem cells, are a small subpopulation of type A spermatogonia with the potential of self-renewal to maintain stem cell pool and differentiation into spermatids in mammalian testis. SSCs are previously regarded as the unipotent stem cells since they can only give rise to sperm within the seminiferous tubules. However, this concept has recently been challenged because numerous studies have demonstrated that SSCs cultured with growth factors can acquire pluripotency to become embryonic stem-like cells. The in vivo and in vitro studies from peers and us have clearly revealed that SSCs can directly transdifferentiate into morphologic, phenotypic, and functional cells of other lineages. Direct conversion to the cells of other tissues has important significance for regenerative medicine. SSCs from azoospermia patients could be induced to differentiate into spermatids with fertilization and developmental potentials. As such, SSCs could have significant applications in both reproductive and regenerative medicine due to their unique and great potentials. In this review, we address the important plasticity of SSCs, with focuses on their self-renewal, differentiation, dedifferentiation, transdifferentiation, and translational medicine studies.

  1. The epidermis comprises autonomous compartments maintained by distinct stem cell populations

    DEFF Research Database (Denmark)

    Page, Mahalia E; Lombard, Patrick; Ng, Felicia

    2013-01-01

    populations. In contrast, upon wounding, stem cell progeny from multiple compartments acquire lineage plasticity and make permanent contributions to regenerating tissue. We further show that oncogene activation in Lrig1(+ve) cells drives hyperplasia but requires auxiliary stimuli for tumor formation....... In summary, our data demonstrate that epidermal stem cells are lineage restricted during homeostasis and suggest that compartmentalization may constitute a conserved mechanism underlying epithelial tissue maintenance....

  2. HOX and TALE signatures specify human stromal stem cell populations from different sources.

    Science.gov (United States)

    Picchi, Jacopo; Trombi, Luisa; Spugnesi, Laura; Barachini, Serena; Maroni, Giorgia; Brodano, Giovanni Barbanti; Boriani, Stefano; Valtieri, Mauro; Petrini, Mario; Magli, Maria Cristina

    2013-04-01

    Human stromal stem cell populations reside in different tissues and anatomical sites, however a critical question related to their efficient use in regenerative medicine is whether they exhibit equivalent biological properties. Here, we compared cellular and molecular characteristics of stromal stem cells derived from the bone marrow, at different body sites (iliac crest, sternum, and vertebrae) and other tissues (dental pulp and colon). In particular, we investigated whether homeobox genes of the HOX and TALE subfamilies might provide suitable markers to identify distinct stromal cell populations, as HOX proteins control cell positional identity and, together with their co-factors TALE, are involved in orchestrating differentiation of adult tissues. Our results show that stromal populations from different sources, although immunophenotypically similar, display distinct HOX and TALE signatures, as well as different growth and differentiation abilities. Stromal stem cells from different tissues are characterized by specific HOX profiles, differing in the number and type of active genes, as well as in their level of expression. Conversely, bone marrow-derived cell populations can be essentially distinguished for the expression levels of specific HOX members, strongly suggesting that quantitative differences in HOX activity may be crucial. Taken together, our data indicate that the HOX and TALE profiles provide positional, embryological and hierarchical identity of human stromal stem cells. Furthermore, our data suggest that cell populations derived from different body sites may not represent equivalent cell sources for cell-based therapeutical strategies for regeneration and repair of specific tissues. Copyright © 2012 Wiley Periodicals, Inc.

  3. Tissue-resident adult stem cell populations of rapidly self-renewing organs

    NARCIS (Netherlands)

    Barker, N.; Bartfeld, S.; Clevers, H.

    2010-01-01

    The epithelial lining of the intestine, stomach, and skin is continuously exposed to environmental assault, imposing a requirement for regular self-renewal. Resident adult stem cell populations drive this renewal, and much effort has been invested in revealing their identity. Reliable adult stem

  4. Ovarian cancer stem cells are enriched in side population and aldehyde dehydrogenase bright overlapping population.

    Directory of Open Access Journals (Sweden)

    Kazuyo Yasuda

    Full Text Available Cancer stem-like cells (CSCs/cancer-initiaiting cells (CICs are defined as a small population of cancer cells that have self-renewal capacity, differentiation potential and high tumor-initiating ability. CSCs/CICs of ovarian cancer have been isolated by side population (SP analysis, ALDEFLUOR assay and using cell surface markers. However, these approaches are not definitive markers for CSCs/CICs, and it is necessary to refine recent methods for identifying more highly purified CSCs/CICs. In this study, we analyzed SP cells and aldehyde dehydrogenese bright (ALDH(Br cells from ovarian cancer cells. Both SP cells and ALDH(Br cells exhibited higher tumor-initiating ability and higher expression level of a stem cell marker, sex determining region Y-box 2 (SOX2, than those of main population (MP cells and ALDH(Low cells, respectively. We analyzed an SP and ALDH(Br overlapping population (SP/ALDH(Br, and the SP/ALDH(Br population exhibited higher tumor-initiating ability than that of SP cells or ALDH(Br cells, enabling initiation of tumor with as few as 10(2 cells. Furthermore, SP/ADLH(Br population showed higher sphere-forming ability, cisplatin resistance, adipocyte differentiation ability and expression of SOX2 than those of SP/ALDH(Low, MP/ALDH(Br and MP/ALDH(Low cells. Gene knockdown of SOX2 suppressed the tumor-initiation of ovarian cancer cells. An SP/ALDH(Br population was detected in several gynecological cancer cells with ratios of 0.1% for HEC-1 endometrioid adenocarcinoma cells to 1% for MCAS ovary mucinous adenocarcinoma cells. Taken together, use of the SP and ALDH(Br overlapping population is a promising approach to isolate highly purified CSCs/CICs and SOX2 might be a novel functional marker for ovarian CSCs/CICs.

  5. Stem cell migration after irradiation

    International Nuclear Information System (INIS)

    Nothdurft, W.; Fliedner, T.M.

    1979-01-01

    The survival rate of irradiated rodents could be significantly improved by shielding only the small parts of hemopoietic tissues during the course of irradiation. The populations of circulating stem cells in adult organisms are considered to be of some importance for the homeostasis between the many sites of blood cell formation and for the necessary flexibility of hemopoietic response in the face of fluctuating demands. Pluripotent stem cells are migrating through peripheral blood as has been shown for several mammalian species. Under steady state conditions, the exchange of stem cells between the different sites of blood cell formation appears to be restricted. Their presence in blood and the fact that they are in balance with the extravascular stem cell pool may well be of significance for the surveilance of the integrity of local stem cell populations. Any decrease of stem cell population in blood below a critical size results in the rapid immigration of circulating stem cells in order to restore local stem cell pool size. Blood stem cells are involved in the regeneration after whole-body irradiation if the stem cell population in bone marrows is reduced to less than 10% of the normal state. In the animals subjected to partial-body irradiation, the circulating stem cells appear to be the only source for the repopulation of the heavily irradiated, aplastic sites of hemopoietic organs. (Yamashita, S.)

  6. Strain differences in the response of mouse testicular stem cells to fractionated radiation

    International Nuclear Information System (INIS)

    Meistrich, M.L.; Finch, M.; Lu, C.C.; de Ruiter-Bootsma, A.L.; de Rooij, D.G.; Davids, J.A.G.

    1984-01-01

    The survival of spermatogonial stem cells in CBA and C3H mice after single and split-dose (24-hr interval) irradiation with fission neutrons and gamma rays was compared. The first doses of the fractionated regimes were either 150 rad (neutrons) or 600 rad (gamma). For both strains the neutron survival curves were exponential. The D 0 value of stem cells in CBA decreased from 83 to 25 rad upon fractionation; that of C3H stem cells decreased only from 54 to 36 rad. The survival curves for gamma irradiation, which all showed shoulders, indicated that C3H stem cells had larger repair capacities than CBA stem cells. However, the most striking difference between the two strains in response to gamma radiation was in the slopes of the second-dose curves. Whereas C3H stem cells showed a small increase of the D 0 upon fractionation (from 196 to 218 rad), CBA stem cells showed a marked decrease (from 243 to 148 rad). The decreases in D 0 upon fractionation, observed in both strains with neutron irradiation and also with gamma irradiation in CBA, are most likely the result of recruitment or progression of radioresistant survivors to a more sensitive state of proliferation or cell cycle phase. It may be that the survivng stem cells in C3H mice are recruited less rapidly and synchronously into active cycle than in CBA mice. Thus, it appears that the strain differences may be quantitative, rather than qualitative

  7. Single-cell sequencing in stem cell biology.

    Science.gov (United States)

    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.

  8. Survival of spermatogonial stem cells in the rat after split dose irradiation during LH-RH analogue treatment

    International Nuclear Information System (INIS)

    Kroonenburgh, M.J.P.G. van; Daal, W.A.J. van; Beck, J.L.; Vemer, H.M.; Rolland, R.

    1987-01-01

    A rat model has been created in which a single injection of an LH-RH analogue depot preparation (Zoladex, ICI 118630) produced a temporary interruption of the pituitary-gonadal axis. This effect applied during irradiation was investigated as a possible mechanism to protect the testis from radiation damage. A local testicular irradiation dose of 6.0 Gy was given either as a single dose or as a fractionated (2 x 3.0 Gy) dose at different time intervals ranging from 8 to 72 h. Stem cell survival was measured 11 weeks after irradiation by means of the repopulation index and the number of haploid cells (spermatids) measured by flow cytometry. Serum gonadotrophins and testosterone concentrations were measured to evaluate hormonal recovery. No significant differences were observed between serum concentrations of follicle-stimulating hormone (FSH), luteinizing hormone (LH) and testosterone and the duration of the fractionation interval. Stem cell survival was higher following fractionated irradiation in comparison with the single dose. For the 8 h interval an increase in recovery ratio was found, amounting to a factor of 5 of the single dose value. The fluctuating pattern of the recovery curves indicated changes in radiosensitivity of stem cells. The combination of hormonal inhibition of spermatogenesis and fractionated irradiation led to a decrease in the absolute numbers of stem cells. However, the stem cell recovery curves were identical to those seen without hormonal inhibition. It was concluded that hormonal pretreatment with Zoladex during split dose irradiation had no protective effect on stem cell survival. 37 refs.; 4 figs

  9. Therapeutic implications of an enriched cancer stem-like cell population in a human osteosarcoma cell line

    International Nuclear Information System (INIS)

    Martins-Neves, Sara R; Lopes, Áurio O; Carmo, Anália do; Paiva, Artur A; Simões, Paulo C; Abrunhosa, Antero J; Gomes, Célia MF

    2012-01-01

    Osteosarcoma is a bone-forming tumor of mesenchymal origin that presents a clinical pattern that is consistent with the cancer stem cell model. Cells with stem-like properties (CSCs) have been identified in several tumors and hypothesized as the responsible for the relative resistance to therapy and tumor relapses. In this study, we aimed to identify and characterize CSCs populations in a human osteosarcoma cell line and to explore their role in the responsiveness to conventional therapies. CSCs were isolated from the human MNNG/HOS cell line using the sphere formation assay and characterized in terms of self-renewal, mesenchymal stem cell properties, expression of pluripotency markers and ABC transporters, metabolic activity and tumorigenicity. Cell's sensitivity to conventional chemotherapeutic agents and to irradiation was analyzed and related with cell cycle-induced alterations and apoptosis. The isolated CSCs were found to possess self-renewal and multipotential differentiation capabilities, express markers of pluripotent embryonic stem cells Oct4 and Nanog and the ABC transporters P-glycoprotein and BCRP, exhibit low metabolic activity and induce tumors in athymic mice. Compared with parental MNNG/HOS cells, CSCs were relatively more resistant to both chemotherapy and irradiation. None of the treatments have induced significant cell-cycle alterations and apoptosis in CSCs. MNNG/HOS osteosarcoma cells contain a stem-like cell population relatively resistant to conventional chemotherapeutic agents and irradiation. This resistant phenotype appears to be related with some stem features, namely the high expression of the drug efflux transporters P-glycoprotein and BCRP and their quiescent nature, which may provide a biological basis for resistance to therapy and recurrence commonly observed in osteosarcoma

  10. Therapeutic implications of an enriched cancer stem-like cell population in a human osteosarcoma cell line

    Directory of Open Access Journals (Sweden)

    Martins-Neves Sara R

    2012-04-01

    Full Text Available Abstract Background Osteosarcoma is a bone-forming tumor of mesenchymal origin that presents a clinical pattern that is consistent with the cancer stem cell model. Cells with stem-like properties (CSCs have been identified in several tumors and hypothesized as the responsible for the relative resistance to therapy and tumor relapses. In this study, we aimed to identify and characterize CSCs populations in a human osteosarcoma cell line and to explore their role in the responsiveness to conventional therapies. Methods CSCs were isolated from the human MNNG/HOS cell line using the sphere formation assay and characterized in terms of self-renewal, mesenchymal stem cell properties, expression of pluripotency markers and ABC transporters, metabolic activity and tumorigenicity. Cell's sensitivity to conventional chemotherapeutic agents and to irradiation was analyzed and related with cell cycle-induced alterations and apoptosis. Results The isolated CSCs were found to possess self-renewal and multipotential differentiation capabilities, express markers of pluripotent embryonic stem cells Oct4 and Nanog and the ABC transporters P-glycoprotein and BCRP, exhibit low metabolic activity and induce tumors in athymic mice. Compared with parental MNNG/HOS cells, CSCs were relatively more resistant to both chemotherapy and irradiation. None of the treatments have induced significant cell-cycle alterations and apoptosis in CSCs. Conclusions MNNG/HOS osteosarcoma cells contain a stem-like cell population relatively resistant to conventional chemotherapeutic agents and irradiation. This resistant phenotype appears to be related with some stem features, namely the high expression of the drug efflux transporters P-glycoprotein and BCRP and their quiescent nature, which may provide a biological basis for resistance to therapy and recurrence commonly observed in osteosarcoma.

  11. Effects of single and split doses of cobalt-60 gamma rays and 14 MeV neutrons on mouse stem cell spermatogonia.

    Science.gov (United States)

    Hacker-Klom, U B; Köhnlein, W; Göhde, W

    2000-12-01

    The long-term effects of ionizing radiation on male gonads may be the result of damage to spermatogonial stem cells. Doses of 10 cGy to 15 Gy (60)Co gamma rays or 10 cGy to 7 Gy 14 MeV neutrons were given to NMRI mice as single or split doses separated by a 24-h interval. The ratios of haploid spermatids/2c cells and the coefficients of variation of DNA histogram peaks as measures of both the cytocidal and the clastogenic actions of radiation were analyzed by DNA flow cytometry after DAPI staining. The coefficient of variation is not only a statistical examination of the data but is also used here as a measure of residual damage to DNA (i.e. a biological dosimeter). Testicular histology was examined in parallel. At 70 days after irradiation, the relative biological effectiveness for neutrons at 50% survival of spermatogonial stem cells was 3.6 for single doses and 2.8 for split doses. The average coefficient of variation of unirradiated controls of elongated spermatids was doubled when stem cells were irradiated with single doses of approximately 14 Gy (60)Co gamma rays or 3 Gy neutrons and observed 70 days later. Split doses of (60)Co gamma rays were more effective than single doses, doubling DNA dispersion at 7 Gy. No fractionation effect was found with neutrons with coefficients of variation.

  12. Aging, metabolism and stem cells: Spotlight on muscle stem cells.

    Science.gov (United States)

    García-Prat, Laura; Muñoz-Cánoves, Pura

    2017-04-15

    All tissues and organs undergo a progressive regenerative decline as they age. This decline has been mainly attributed to loss of stem cell number and/or function, and both stem cell-intrinsic changes and alterations in local niches and/or systemic environment over time are known to contribute to the stem cell aging phenotype. Advancing in the molecular understanding of the deterioration of stem cell cells with aging is key for targeting the specific causes of tissue regenerative dysfunction at advanced stages of life. Here, we revise exciting recent findings on why stem cells age and the consequences on tissue regeneration, with a special focus on regeneration of skeletal muscle. We also highlight newly identified common molecular pathways affecting diverse types of aging stem cells, such as altered proteostasis, metabolism, or senescence entry, and discuss the questions raised by these findings. Finally, we comment on emerging stem cell rejuvenation strategies, principally emanating from studies on muscle stem cells, which will surely burst tissue regeneration research for future benefit of the increasing human aging population. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  13. A distinct hematopoietic stem cell population for rapid multilineage engraftment in nonhuman primates.

    Science.gov (United States)

    Radtke, Stefan; Adair, Jennifer E; Giese, Morgan A; Chan, Yan-Yi; Norgaard, Zachary K; Enstrom, Mark; Haworth, Kevin G; Schefter, Lauren E; Kiem, Hans-Peter

    2017-11-01

    Hematopoietic reconstitution after bone marrow transplantation is thought to be driven by committed multipotent progenitor cells followed by long-term engrafting hematopoietic stem cells (HSCs). We observed a population of early-engrafting cells displaying HSC-like behavior, which persisted long-term in vivo in an autologous myeloablative transplant model in nonhuman primates. To identify this population, we characterized the phenotype and function of defined nonhuman primate hematopoietic stem and progenitor cell (HSPC) subsets and compared these to human HSPCs. We demonstrated that the CD34 + CD45RA - CD90 + cell phenotype is highly enriched for HSCs. This population fully supported rapid short-term recovery and robust multilineage hematopoiesis in the nonhuman primate transplant model and quantitatively predicted transplant success and time to neutrophil and platelet recovery. Application of this cell population has potential in the setting of HSC transplantation and gene therapy/editing approaches. Copyright © 2017 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.

  14. Plant stem cell niches.

    Science.gov (United States)

    Stahl, Yvonne; Simon, Rüdiger

    2005-01-01

    Stem cells are required to support the indeterminate growth style of plants. Meristems are a plants stem cell niches that foster stem cell survival and the production of descendants destined for differentiation. In shoot meristems, stem cell fate is decided at the populational level. The size of the stem cell domain at the meristem tip depends on signals that are exchanged with cells of the organizing centre underneath. In root meristems, individual stem cells are controlled by direct interaction with cells of the quiescent centre that lie in the immediate neighbourhood. Analysis of the interactions and signaling processes in the stem cell niches has delivered some insights into the molecules that are involved and revealed that the two major niches for plant stem cells are more similar than anticipated.

  15. Increasing magnetite contents of polymeric magnetic particles dramatically improves labeling of neural stem cell transplant populations.

    Science.gov (United States)

    Adams, Christopher F; Rai, Ahmad; Sneddon, Gregor; Yiu, Humphrey H P; Polyak, Boris; Chari, Divya M

    2015-01-01

    Safe and efficient delivery of therapeutic cells to sites of injury/disease in the central nervous system is a key goal for the translation of clinical cell transplantation therapies. Recently, 'magnetic cell localization strategies' have emerged as a promising and safe approach for targeted delivery of magnetic particle (MP) labeled stem cells to pathology sites. For neuroregenerative applications, this approach is limited by the lack of available neurocompatible MPs, and low cell labeling achieved in neural stem/precursor populations. We demonstrate that high magnetite content, self-sedimenting polymeric MPs [unfunctionalized poly(lactic acid) coated, without a transfecting component] achieve efficient labeling (≥90%) of primary neural stem cells (NSCs)-a 'hard-to-label' transplant population of major clinical relevance. Our protocols showed high safety with respect to key stem cell regenerative parameters. Critically, labeled cells were effectively localized in an in vitro flow system by magnetic force highlighting the translational potential of the methods used. Copyright © 2015 Elsevier Inc. All rights reserved.

  16. Heterogeneity of breast cancer stem cells as evidenced with Notch-dependent and Notch-independent populations

    International Nuclear Information System (INIS)

    Wong, Nelson K Y; Fuller, Megan; Sung, Sandy; Wong, Fred; Karsan, Aly

    2012-01-01

    Studies have suggested the potential importance of Notch signaling to the cancer stem cell population in some tumors, but it is not known whether all cells in the cancer stem cell fraction require Notch activity. To address this issue, we blocked Notch activity in MCF-7 cells by expressing a dominant-negative MAML-GFP (dnMAML) construct, which inhibits signaling through all Notch receptors, and quantified the effect on tumor-initiating activity. Inhibition of Notch signaling reduced primary tumor sphere formation and side population. Functional quantification of tumor-initiating cell numbers in vivo showed a significant decrease, but not a complete abrogation, of these cells in dnMAML-expressing cells. Interestingly, when assessed in secondary assays in vitro or in vivo, there was no difference in tumor-initiating activity between the dnMAML-expressing cells and control cells. The fact that a subpopulation of dnMAML-expressing cells was capable of forming primary and secondary tumors indicates that there are Notch-independent tumor-initiating cells in the breast cancer cell line MCF-7. Our findings thus provide direct evidence for a heterogeneous cancer stem cell pool, which will require combination therapies against multiple oncogenic pathways to eliminate the tumor-initiating cell population

  17. Stem Cells in Burn Eschar

    NARCIS (Netherlands)

    van der Veen, V. C.; Vlig, M.; van Milligen-Kummer, F.J.; de Vries, S.I.; Middelkoop, E.; Ulrich, M.

    2012-01-01

    This study compares mesenchymal cells isolated from excised burn wound eschar with adipose-derived stem cells (ASCs) and dermal fibroblasts in their ability to conform to the requirements for multipotent mesenchymal stem cells (MSCs). A population of multipotent stem cells in burn eschar could be an

  18. Sensing radiosensitivity of human epidermal stem cells

    International Nuclear Information System (INIS)

    Rachidi, Walid; Harfourche, Ghida; Lemaitre, Gilles; Amiot, Franck; Vaigot, Pierre; Martin, Michele T.

    2007-01-01

    Purpose: Radiosensitivity of stem cells is a matter of debate. For mouse somatic stem cells, both radiosensitive and radioresistant stem cells have been described. By contrast, the response of human stem cells to radiation has been poorly studied. As epidermis is a radiosensitive tissue, we evaluated in the present work the radiosensitivity of cell populations enriched for epithelial stem cells of human epidermis. Methods and materials: The total keratinocyte population was enzymatically isolated from normal human skin. We used flow cytometry and antibodies against cell surface markers to isolate basal cell populations from human foreskin. Cell survival was measured after a dose of 2 Gy with the XTT assay at 72 h after exposure and with a clonogenic assay at 2 weeks. Transcriptome analysis using oligonucleotide microarrays was performed to assess the genomic cell responses to radiation. Results: Cell sorting based on two membrane proteins, α6 integrin and the transferrin receptor CD71, allowed isolation of keratinocyte populations enriched for the two types of cells found in the basal layer of epidermis: stem cells and progenitors. Both the XTT assay and the clonogenic assay showed that the stem cells were radioresistant whereas the progenitors were radiosensitive. We made the hypothesis that upstream DNA damage signalling might be different in the stem cells and used microarray technology to test this hypothesis. The stem cells exhibited a much more reduced gene response to a dose of 2 Gy than the progenitors, as we found that 6% of the spotted genes were regulated in the stem cells and 20% in the progenitors. Using Ingenuity Pathway Analysis software, we found that radiation exposure induced very specific pathways in the stem cells. The most striking responses were the repression of a network of genes involved in apoptosis and the induction of a network of cytokines and growth factors. Conclusion: These results show for the first time that keratinocyte

  19. Biochemistry of epidermal stem cells.

    Science.gov (United States)

    Eckert, Richard L; Adhikary, Gautam; Balasubramanian, Sivaprakasam; Rorke, Ellen A; Vemuri, Mohan C; Boucher, Shayne E; Bickenbach, Jackie R; Kerr, Candace

    2013-02-01

    The epidermis is an important protective barrier that is essential for maintenance of life. Maintaining this barrier requires continuous cell proliferation and differentiation. Moreover, these processes must be balanced to produce a normal epidermis. The stem cells of the epidermis reside in specific locations in the basal epidermis, hair follicle and sebaceous glands and these cells are responsible for replenishment of this tissue. A great deal of effort has gone into identifying protein epitopes that mark stem cells, in identifying stem cell niche locations, and in understanding how stem cell populations are related. We discuss these studies as they apply to understanding normal epidermal homeostasis and skin cancer. An assortment of stem cell markers have been identified that permit assignment of stem cells to specific regions of the epidermis, and progress has been made in understanding the role of these cells in normal epidermal homeostasis and in conditions of tissue stress. A key finding is the multiple stem cell populations exist in epidermis that give rise to different structures, and that multiple stem cell types may contribute to repair in damaged epidermis. Understanding epidermal stem cell biology is likely to lead to important therapies for treating skin diseases and cancer, and will also contribute to our understanding of stem cells in other systems. This article is part of a Special Issue entitled Biochemistry of Stem Cells. Copyright © 2012 Elsevier B.V. All rights reserved.

  20. Comparison of tumor biology of two distinct cell sub-populations in lung cancer stem cells.

    Science.gov (United States)

    Wang, Jianyu; Sun, Zhiwei; Liu, Yongli; Kong, Liangsheng; Zhou, Shixia; Tang, Junlin; Xing, Hongmei Rosie

    2017-11-14

    Characterization of the stem-like properties of cancer stem cells (CSCs) remain indirect and qualitative, especially the ability of CSCs to undergo asymmetric cell division for self renewal and differentiation, a unique property of cells of stem origin. It is partly due to the lack of stable cellular models of CSCs. In this study, we developed a new approach for CSC isolation and purification to derive a CSC-enriched cell line (LLC-SE). By conducting five consecutive rounds of single cell cloning using the LLC-SE cell line, we obtained two distinct sub-population of cells within the Lewis lung cancer CSCs that employed largely symmetric division for self-renewal (LLC-SD) or underwent asymmetric division for differentiation (LLC-ASD). LLC-SD and LLC-ASD cell lines could be stably passaged in culture and be distinguished by cell morphology, stem cell marker, spheroid formation and subcutaneous tumor initiation efficiency, as well as orthotopic lung tumor growth, progression and survival. The ability LLC-ASD cells to undergo asymmetric division was visualized and quantified by the asymmetric segregation of labeled BrdU and NUMB to one of the two daughter cells in anaphase cell division. The more stem-like LLC-SD cells exhibited higher capacity for tumorigenesis and progression and shorter survival. As few as 10 LLC-SD could initiate subcutaneous tumor growth when transplanted to the athymic mice. Collectively, these observations suggest that the SD-type of cells appear to be on the top of the hierarchical order of the CSCs. Furthermore, they have lead to generated cellular models of CSC self-renewal for future mechanistic investigations.

  1. Stem cell plasticity enables hair regeneration following Lgr5+ cell loss.

    Science.gov (United States)

    Hoeck, Joerg D; Biehs, Brian; Kurtova, Antonina V; Kljavin, Noelyn M; de Sousa E Melo, Felipe; Alicke, Bruno; Koeppen, Hartmut; Modrusan, Zora; Piskol, Robert; de Sauvage, Frederic J

    2017-06-01

    Under injury conditions, dedicated stem cell populations govern tissue regeneration. However, the molecular mechanisms that induce stem cell regeneration and enable plasticity are poorly understood. Here, we investigate stem cell recovery in the context of the hair follicle to understand how two molecularly distinct stem cell populations are integrated. Utilizing diphtheria-toxin-mediated cell ablation of Lgr5 + (leucine-rich repeat-containing G-protein-coupled receptor 5) stem cells, we show that killing of Lgr5 + cells in mice abrogates hair regeneration but this is reversible. During recovery, CD34 + (CD34 antigen) stem cells activate inflammatory response programs and start dividing. Pharmacological attenuation of inflammation inhibits CD34 + cell proliferation. Subsequently, the Wnt pathway controls the recovery of Lgr5 + cells and inhibition of Wnt signalling prevents Lgr5 + cell and hair germ recovery. Thus, our study uncovers a compensatory relationship between two stem cell populations and the underlying molecular mechanisms that enable hair follicle regeneration.

  2. Selfish spermatogonial selection: evidence from an immunohistochemical screen in testes of elderly men.

    Directory of Open Access Journals (Sweden)

    Jasmine Lim

    Full Text Available The dominant congenital disorders Apert syndrome, achondroplasia and multiple endocrine neoplasia-caused by specific missense mutations in the FGFR2, FGFR3 and RET proteins respectively-represent classical examples of paternal age-effect mutation, a class that arises at particularly high frequencies in the sperm of older men. Previous analyses of DNA from randomly selected cadaveric testes showed that the levels of the corresponding FGFR2, FGFR3 and RET mutations exhibit very uneven spatial distributions, with localised hotspots surrounded by large mutation-negative areas. These studies imply that normal testes are mosaic for clusters of mutant cells: these clusters are predicted to have altered growth and signalling properties leading to their clonal expansion (selfish spermatogonial selection, but DNA extraction eliminates the possibility to study such processes at a tissue level. Using a panel of antibodies optimised for the detection of spermatocytic seminoma, a rare tumour of spermatogonial origin, we demonstrate that putative clonal events are frequent within normal testes of elderly men (mean age: 73.3 yrs and can be classed into two broad categories. We found numerous small (less than 200 cells cellular aggregations with distinct immunohistochemical characteristics, localised to a portion of the seminiferous tubule, which are of uncertain significance. However more infrequently we identified additional regions where entire seminiferous tubules had a circumferentially altered immunohistochemical appearance that extended through multiple serial sections that were physically contiguous (up to 1 mm in length, and exhibited enhanced staining for antibodies both to FGFR3 and a marker of downstream signal activation, pAKT. These findings support the concept that populations of spermatogonia in individual seminiferous tubules in the testes of older men are clonal mosaics with regard to their signalling properties and activation, thus fulfilling

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

    Science.gov (United States)

    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.

  4. What is a stem cell?

    Science.gov (United States)

    Slack, Jonathan M W

    2018-05-15

    The historical roots of the stem cell concept are traced with respect to its usage in embryology and in hematology. The modern consensus definition of stem cells, comprising both pluripotent stem cells in culture and tissue-specific stem cells in vivo, is explained and explored. Methods for identifying stem cells are discussed with respect to cell surface markers, telomerase, label retention and transplantability, and properties of the stem cell niche are explored. The CreER method for identifying stem cells in vivo is explained, as is evidence in favor of a stochastic rather than an obligate asymmetric form of cell division. In conclusion, it is found that stem cells do not possess any unique and specific molecular markers; and stem cell behavior depends on the environment of the cell as well as the stem cell's intrinsic qualities. Furthermore, the stochastic mode of division implies that stem cell behavior is a property of a cell population not of an individual cell. In this sense, stem cells do not exist in isolation but only as a part of multicellular system. This article is categorized under: Adult Stem Cells, Tissue Renewal, and Regeneration > Tissue Stem Cells and Niches Adult Stem Cells, Tissue Renewal, and Regeneration > Methods and Principles Adult Stem Cells, Tissue Renewal, and Regeneration > Environmental Control of Stem Cells. © 2018 Wiley Periodicals, Inc.

  5. Stem cell-based approaches in dentistry

    Directory of Open Access Journals (Sweden)

    TA Mitsiadis

    2011-11-01

    Full Text Available Repair of dental pulp and periodontal lesions remains a major clinical challenge. Classical dental treatments require the use of specialised tissue-adapted materials with still questionable efficacy and durability. Stem cell-based therapeutic approaches could offer an attractive alternative in dentistry since they can promise physiologically improved structural and functional outcomes. These therapies necessitate a sufficient number of specific stem cell populations for implantation. Dental mesenchymal stem cells can be easily isolated and are amenable to in vitro expansion while retaining their stemness. In vivo studies realised in small and large animals have evidenced the potential of dental mesenchymal stem cells to promote pulp and periodontal regeneration, but have also underlined new important challenges. The homogeneity of stem cell populations and their quality control, the delivery method, the quality of the regenerated dental tissues and their integration to the host tissue are some of the key challenges. The use of bioactive scaffolds that can elicit effective tissue repair response, through activation and mobilisation of endogenous stem cell populations, constitutes another emerging therapeutic strategy. Finally, the use of stem cells and induced pluripotent cells for the regeneration of entire teeth represents a novel promising alternative to dental implant treatment after tooth loss. In this mini-review, we present the currently applied techniques in restorative dentistry and the various attempts that are made to bridge gaps in knowledge regarding treatment strategies by translating basic stem cell research into the dental practice.

  6. Lipopolysaccharide inhibits the self-renewal of spermatogonial stem cells in vitro via downregulation of GDNF expression in Sertoli cells.

    Science.gov (United States)

    Zhang, Xiaoli; Shi, Kun; Li, Yi; Zhang, Haiyu; Hao, Jing

    2014-06-01

    Lipopolysaccharide (LPS) can reduce sperm count and sperm quality. The molecular mechanisms underlying this process are not fully understood. In this report, we investigated the effects of LPS-treated Sertoli cells on self-renewal and differentiation of spermatogoinial stem cells (SSCs). Sertoli cell cultures were established and incubated with LPS (10μg/ml) for 1, 2 or 3 days, respectively. The culture media were collected and used as conditioned media (CM) to culture SSCs. The expression of glial cell-derived neurotrophic factor (GDNF), stem cell factor (SCF) and bone morphogenetic protein 4 (BMP4) in Sertoli cells treated with LPS was analyzed by RT-PCR and Western blotting. The results showed that the expression of SSC differentiation markers, c-kit and Sohlh2, was increased, while the expression of SSC self-renewal markers, plzf, oct4, and PCNA, was repressed when cultured in CM from LPS-treated Sertoli cells. GDNF levels in Sertoli cells and CM reduced dramatically after LPS treatments, while SCF and BMP4 levels did not show any significant changes. Moreover, correlated with the GDNF levels in CM, GDNF target genes, Bcl6b and Etv5, were reduced markedly in SSCs. Our results suggest that LPS inhibits the expression of GDNF in Sertoli cells, and might prevent the SSC self-renewal via down-regulation of GDNF target genes. Copyright © 2014 Elsevier Inc. All rights reserved.

  7. Limbal Stem Cell Deficiency and Treatment with Stem Cell Transplantation.

    Science.gov (United States)

    Barut Selver, Özlem; Yağcı, Ayşe; Eğrilmez, Sait; Gürdal, Mehmet; Palamar, Melis; Çavuşoğlu, Türker; Ateş, Utku; Veral, Ali; Güven, Çağrı; Wolosin, Jose Mario

    2017-10-01

    The cornea is the outermost tissue of the eye and it must be transparent for the maintenance of good visual function. The superficial epithelium of the cornea, which is renewed continuously by corneal stem cells, plays a critical role in the permanence of this transparency. These stem cells are localized at the cornea-conjunctival transition zone, referred to as the limbus. When this zone is affected/destroyed, limbal stem cell deficiency ensues. Loss of limbal stem cell function allows colonization of the corneal surface by conjunctival epithelium. Over 6 million people worldwide are affected by corneal blindness, and limbal stem cell deficiency is one of the main causes. Fortunately, it is becoming possible to recover vision by autologous transplantation of limbal cells obtained from the contralateral eye in unilateral cases. Due to the potential risks to the donor eye, only a small amount of tissue can be obtained, in which only 1-2% of the limbal epithelial cells are actually limbal stem cells. Vigorous attempts are being made to expand limbal stem cells in culture to preserve or even enrich the stem cell population. Ex vivo expanded limbal stem cell treatment in limbal stem cell deficiency was first reported in 1997. In the 20 years since, various protocols have been developed for the cultivation of limbal epithelial cells. It is still not clear which method promotes effective stem cell viability and this remains a subject of ongoing research. The most preferred technique for limbal cell culture is the explant culture model. In this approach, a small donor eye limbal biopsy is placed as an explant onto a biocompatible substrate (preferably human amniotic membrane) for expansion. The outgrowth (cultivated limbal epithelial cells) is then surgically transferred to the recipient eye. Due to changing regulations concerning cell-based therapy, the implementation of cultivated limbal epithelial transplantation in accordance with Good Laboratory Practice using

  8. Different culture conditions affect the growth of human tendon stem/progenitor cells (TSPCs) within a mixed tendon cells (TCs) population.

    Science.gov (United States)

    Viganò, M; Perucca Orfei, C; Colombini, A; Stanco, D; Randelli, P; Sansone, V; de Girolamo, L

    2017-12-01

    Tendon resident cells (TCs) are a mixed population made of terminally differentiated tenocytes and tendon stem/progenitor cells (TSPCs). Since the enrichment of progenitors proportion could enhance the effectiveness of treatments based on these cell populations, the interest on the effect of culture conditions on the TSPCs is growing. In this study the clonal selection and the culture in presence or absence of basic fibroblast growth factor (bFGF) were used to assess their influences on the stemness properties and phenotype specific features of tendon cells. Cells cultured with the different methods were analyzed in terms of clonogenic and differentiation abilities, stem and tendon specific genes expression and immunophenotype at passage 2 and passage 4. The clonal selection allowed to isolate cells with a higher multi-differentiation potential, but at the same time a lower proliferation rate in comparison to the whole population. Moreover, the clones express a higher amounts of stemness marker OCT4 and tendon specific transcription factor Scleraxis (SCX) mRNA, but a lower level of decorin (DCN). On the other hand, the number of cells obtained by clonal selection was extremely low and most of the clones were unable to reach a high number of passages in cultures. The presence of bFGF influences TCs morphology, enhance their proliferation rate and reduce their clonogenic ability. Interestingly, the expression of CD54, a known mesenchymal stem cell marker, is reduced in presence of bFGF at early passages. Nevertheless, bFGF does not affect the chondrogenic and osteogenic potential of TCs and the expression of tendon specific markers, while it was able to downregulate the OCT4 expression. This study showed that clonal selection enhance progenitors content in TCs populations, but the extremely low number of cells produced with this method could represent an insurmountable obstacle to its application in clinical approaches. We observed that the addition of bFGF to the

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

    Science.gov (United States)

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

    2018-01-01

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

  10. Brain mesenchymal stem cells: The other stem cells of the brain?

    Science.gov (United States)

    Appaix, Florence; Nissou, Marie-France; van der Sanden, Boudewijn; Dreyfus, Matthieu; Berger, François; Issartel, Jean-Paul; Wion, Didier

    2014-04-26

    Multipotent mesenchymal stromal cells (MSC), have the potential to differentiate into cells of the mesenchymal lineage and have non-progenitor functions including immunomodulation. The demonstration that MSCs are perivascular cells found in almost all adult tissues raises fascinating perspectives on their role in tissue maintenance and repair. However, some controversies about the physiological role of the perivascular MSCs residing outside the bone marrow and on their therapeutic potential in regenerative medicine exist. In brain, perivascular MSCs like pericytes and adventitial cells, could constitute another stem cell population distinct to the neural stem cell pool. The demonstration of the neuronal potential of MSCs requires stringent criteria including morphological changes, the demonstration of neural biomarkers expression, electrophysiological recordings, and the absence of cell fusion. The recent finding that brain cancer stem cells can transdifferentiate into pericytes is another facet of the plasticity of these cells. It suggests that the perversion of the stem cell potential of pericytes might play an even unsuspected role in cancer formation and tumor progression.

  11. Elimination of mouse tumor cells from neonate spermatogonial cells utilizing cisplatin-entrapped folic acid-conjugated poly(lactic-co-glycolic acid) nanoparticles in vitro.

    Science.gov (United States)

    Shabani, Ronak; Ashjari, Mohsen; Ashtari, Khadijeh; Izadyar, Fariborz; Behnam, Babak; Khoei, Samideh; Asghari-Jafarabadi, Mohamad; Koruji, Morteza

    2018-01-01

    Some male survivors of childhood cancer are suffering from azoospermia. In addition, spermatogonial stem cells (SSCs) are necessary for the improvement of spermatogenesis subsequent to exposure to cytotoxic agents such as cisplatin. The aim of this study was to evaluate the anticancer activity of cisplatin-loaded folic acid-conjugated poly(lactic-co-glycolic acid) (PLGA) nanoparticles (NPs) on mouse malignant cell line (EL4) and SSCs in vitro. SSCs were co-cultured with mouse malignant cell line (EL4) cells and divided into four culture groups: 1) control (cells were co-cultured in the culture medium), 2) co-cultured cells were treated with cisplatin (10 μg/mL), 3) co-cultured cells were treated with cisplatin-loaded folic acid-conjugated PLGA NPs, and 4) co-cultures were treated with folic acid-conjugated PLGA for 48 hours. The NPs were prepared, characterized, and targeted with folate. In vitro release characteristics, loading efficiency, and scanning electron microscopy and transmission electron microscopy images were studied. Cancer cells were assayed after treatment using flow cytometry and TUNEL assay. The co-cultures of SSCs and EL4 cells were injected into seminiferous tubules of the testes after treating with cis-diaminedichloroplatinum/PLGA NPs. The mean diameter of PLGA NPs ranged between 150 and 250 nm. The number of TUNEL-positive cells increased, and the expression of Bax and caspase-3 were upregulated in EL4 cells in Group 4 compared with Group 2. There was no pathological tumor in testes after transplantation with treated co-cultured cells. The PLGA NPs appeared to act as a promising carrier for cisplatin administration, which was consistent with a higher activation of apoptosis than free drug.

  12. [Perinatal sources of stem cells].

    Science.gov (United States)

    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.

  13. Derivation of keratinocytes from chicken embryonic stem cells: Establishment and characterization of differentiated proliferative cell populations

    Directory of Open Access Journals (Sweden)

    Mathilde Couteaudier

    2015-03-01

    Full Text Available A common challenge in avian cell biology is the generation of differentiated cell-lines, especially in the keratinocyte lineage. Only a few avian cell-lines are available and very few of them show an interesting differentiation profile. During the last decade, mammalian embryonic stem cell-lines were shown to differentiate into almost all lineages, including keratinocytes. Although chicken embryonic stem cells had been obtained in the 1990s, few differentiation studies toward the ectodermal lineage were reported. Consequently, we explored the differentiation of chicken embryonic stem cells toward the keratinocyte lineage by using a combination of stromal induction, ascorbic acid, BMP4 and chicken serum. During the induction period, we observed a downregulation of pluripotency markers and an upregulation of epidermal markers. Three homogenous cell populations were derived, which were morphologically similar to chicken primary keratinocytes, displaying intracellular lipid droplets in almost every pavimentous cell. These cells could be serially passaged without alteration of their morphology and showed gene and protein expression profiles of epidermal markers similar to chicken primary keratinocytes. These cells represent an alternative to the isolation of chicken primary keratinocytes, being less cumbersome to handle and reducing the number of experimental animals used for the preparation of primary cells.

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

    Directory of Open Access Journals (Sweden)

    Loredana Alberti

    Full Text Available 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.

  15. Technology advancement for integrative stem cell analyses.

    Science.gov (United States)

    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.

  16. Perinatal sources of stem cells

    Directory of Open Access Journals (Sweden)

    Magdalena Maria Piskorska-Jasiulewicz

    2015-03-01

    Full Text Available 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. Methods for Stem Cell Production and Therapy

    Science.gov (United States)

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

    DEFF Research Database (Denmark)

    Horwood, Nicole J.; Dazzi, Francesco; Zaher, Walid

    2012-01-01

    Mesenchymal stem cells (MSC) are stem cell populations present among the bone marrow stroma and a number of other tissues that are capable of multi-lineage differentiation into mesoderm-type cells such as osteoblasts, adipocytes and chondrocytes. MSC provide supportive stroma for growth...... and differentiation of hematopoietic stem cells (HSC) and hematopoiesis. These cells have been described as important immunoregulators due to their ability to suppress T cells proliferation. MSC can also directly contribute to tissue repair by migrating to sites of injury and providing a source of cells...... for differentiation and/or providing bystander support for resident stromal cells. This chapter discusses the cellular and molecular properties of MSC, the mechanisms by which they can modulate immune responses and the clinical applications of MSC in disorders such as graft-versus-host disease and aplastic anaemia...

  19. Stem cell biology meets systems biology

    OpenAIRE

    Roeder, I.; Radtke, F.

    2009-01-01

    Stem cells and their descendents are the building blocks of life. How stem cell populations guarantee their maintenance and/or self-renewal, and how individual stem cells decide to transit from one cell stage to another to generate different cell types are long-standing and fascinating questions in the field. Here, we review the discussions that took place at a recent EMBO conference in Cambridge, UK, in which these questions were placed in the context of the latest advances in stem cell biol...

  20. Systems Biology and Stem Cell Pluripotency

    DEFF Research Database (Denmark)

    Mashayekhi, Kaveh; Hall, Vanessa Jane; Freude, Kristine

    2016-01-01

    Recent breakthroughs in stem cell biology have accelerated research in the area of regenerative medicine. Over the past years, it has become possible to derive patient-specific stem cells which can be used to generate different cell populations for potential cell therapy. Systems biological...... modeling of stem cell pluripotency and differentiation have largely been based on prior knowledge of signaling pathways, gene regulatory networks, and epigenetic factors. However, there is a great need to extend the complexity of the modeling and to integrate different types of data, which would further...... improve systems biology and its uses in the field. In this chapter, we first give a general background on stem cell biology and regenerative medicine. Stem cell potency is introduced together with the hierarchy of stem cells ranging from pluripotent embryonic stem cells (ESCs) and induced pluripotent stem...

  1. A population of serumdeprivation-induced bone marrow stem cells (SD-BMSC) expresses marker typical for embryonic and neural stem cells

    International Nuclear Information System (INIS)

    Sauerzweig, Steven; Munsch, Thomas; Lessmann, Volkmar; Reymann, Klaus G.; Braun, Holger

    2009-01-01

    The bone marrow represents an easy accessible source of adult stem cells suitable for various cell based therapies. Several studies in recent years suggested the existence of pluripotent stem cells within bone marrow stem cells (BMSC) expressing marker proteins of both embryonic and tissue committed stem cells. These subpopulations were referred to as MAPC, MIAMI and VSEL-cells. Here we describe SD-BMSC (serumdeprivation-induced BMSC) which are induced as a distinct subpopulation after complete serumdeprivation. SD-BMSC are generated from small-sized nestin-positive BMSC (S-BMSC) organized as round-shaped cells in the top layer of BMSC-cultures. The generation of SD-BMSC is caused by a selective proliferation of S-BMSC and accompanied by changes in both morphology and gene expression. SD-BMSC up-regulate not only markers typical for neural stem cells like nestin and GFAP, but also proteins characteristic for embryonic cells like Oct4 and SOX2. We hypothesize, that SD-BMSC like MAPC, MIAMI and VSEL-cells represent derivatives from a single pluripotent stem cell fraction within BMSC exhibiting characteristics of embryonic and tissue committed stem cells. The complete removal of serum might offer a simple way to specifically enrich this fraction of pluripotent embryonic like stem cells in BMSC cultures

  2. Organization of haemopoietic stem cells: the generation-age hypothesis

    International Nuclear Information System (INIS)

    Rosendaal, M.; Hodgson, G.S.; Bradley, T.R.

    1978-01-01

    This paper proposes that the previous division history of each stem cell is one determinant of the functional organisation of the haemopoietic stem cell population. Older stem cell are used to form blood before younger ones. The stem cells generating capacity of a lineage is finite, and cells are eventually lost to the system by forming two committed precursors of the cell lines, and the next oldest stem cell takes over. Hence the proposed term 'generation-age hypothesis', supported by experimental evidence. Older stem cells from normal bone marrow and 13 day foetal liver were stripped away with phase-specific drugs revealing a younger population of stem cells with three-to four-fold greater stem cell generating capacity. Normal stem cells aged by continuous irradiation and serial retransplantation had eight-fold reduced generating capacity. That of stem cells in the bloodstream was half to a quarter that of normal bone marrow stem cells. There were some circulating stem cells, identified by reaction to brain-associated antigen, positive for 75% of normal femoral stem cells but not their progeny, whose capacity for stem cell generation was an eighth to one fortieth that of normal cells. (U.K.)

  3. Spermatogonial cell killing by radiolabeled methionine: a comparative study of the effects of Se-17, S-35, and H-3

    International Nuclear Information System (INIS)

    Rao, D.V.; Govelitz, G.F.; Sastry, K.S.R.; Howell, R.W.

    1986-01-01

    Spermatogenesis in the testes of mice offers an effective experimental model to investigate the biological effects and the dosimetry of Auger electron emitters in vivo, aspects that are not yet well understood. Killing of the radiosensitive spermatogonia by intratesticularly localized radionuclides is the biological effect of interest, manifesting as reduced sperm-head population four to six weeks after the initial administration of the radionuclides. The authors present here results of a comparative study of the effects of the Auger-emitter, 75 Se, and the beta-emitters, 35 S and 3 H, when these radionuclides are attached to methionine, and hence distributed similarly in the testis and in the cytoplasmic protein fractions of the spermatogonial cells. The sperm-head survival is assayed on the 36th day post-injection, when the sperm-head population reaches its minimum after the initial intratesticular administration of the radionuclides. In all the three cases, the survival fractions display similar dependence on the conventionally calculated average dose to the organ. These results show the adequacy of conventional dosimetry when 75 Se is localized in the cytoplasm of the cells, and emphasize the relative inefficiency of Auger electrons emitted from cytoplasmic decay sites in irradiating the radiosensitive DNA in the cells. 21 references, 4 figures, 4 tables

  4. Stem cells in pharmaceutical biotechnology.

    Science.gov (United States)

    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

  5. Endothelial Progenitor Cell Fraction Contained in Bone Marrow-Derived Mesenchymal Stem Cell Populations Impairs Osteogenic Differentiation

    Directory of Open Access Journals (Sweden)

    Fabian Duttenhoefer

    2015-01-01

    Full Text Available In bone tissue engineering (TE endothelial cell-osteoblast cocultures are known to induce synergies of cell differentiation and activity. Bone marrow mononucleated cells (BMCs are a rich source of mesenchymal stem cells (MSCs able to develop an osteogenic phenotype. Endothelial progenitor cells (EPCs are also present within BMC. In this study we investigate the effect of EPCs present in the BMC population on MSCs osteogenic differentiation. Human BMCs were isolated and separated into two populations. The MSC population was selected through plastic adhesion capacity. EPCs (CD34+ and CD133+ were removed from the BMC population and the resulting population was named depleted MSCs. Both populations were cultured over 28 days in osteogenic medium (Dex+ or medium containing platelet lysate (PL. MSC population grew faster than depleted MSCs in both media, and PL containing medium accelerated the proliferation for both populations. Cell differentiation was much higher in Dex+ medium in both cases. Real-time RT-PCR revealed upregulation of osteogenic marker genes in depleted MSCs. Higher values of ALP activity and matrix mineralization analyses confirmed these results. Our study advocates that absence of EPCs in the MSC population enables higher osteogenic gene expression and matrix mineralization and therefore may lead to advanced bone neoformation necessary for TE constructs.

  6. CD146/MCAM defines functionality of human bone marrow stromal stem cell populations

    DEFF Research Database (Denmark)

    Harkness, Linda; Zaher, Walid; Ditzel, Nicholas

    2016-01-01

    BACKGROUND: Identification of surface markers for prospective isolation of functionally homogenous populations of human skeletal (stromal, mesenchymal) stem cells (hMSCs) is highly relevant for cell therapy protocols. Thus, we examined the possible use of CD146 to subtype a heterogeneous hMSC...... population. METHODS: Using flow cytometry and cell sorting, we isolated two distinct hMSC-CD146(+) and hMSC-CD146(-) cell populations from the telomerized human bone marrow-derived stromal cell line (hMSC-TERT). Cells were examined for differences in their size, shape and texture by using high...... and adipocytes on the basis of gene expression and protein production of lineage-specific markers. In vivo, hMSC-CD146(+) and hMSC-CD146(-) cells formed bone and bone marrow organ when implanted subcutaneously in immune-deficient mice. Bone was enriched in hMSC-CD146(-) cells (12.6 % versus 8.1 %) and bone...

  7. Stem cell-derived vascular endothelial cells and their potential application in regenerative medicine

    Science.gov (United States)

    Although a 'vascular stem cell' population has not been identified or generated, vascular endothelial and mural cells (smooth muscle cells and pericytes) can be derived from currently known pluripotent stem cell sources, including human embryonic stem cells and induced pluripotent stem cells. We rev...

  8. Stem Cell Therapies in Orthopaedic Trauma

    OpenAIRE

    Marcucio, Ralph S.; Nauth, Aaron; Giannoudis, Peter V.; Bahney, Chelsea; Piuzzi, Nicolas S.; Muschler, George; Miclau, Theodore

    2015-01-01

    Stem cells offer great promise to help understand the normal mechanisms of tissue renewal, regeneration, and repair, and also for development of cell-based therapies to treat patients after tissue injury. Most adult tissues contain stem cells and progenitor cells that contribute to homeostasis, remodeling and repair. Multiple stem and progenitor cell populations in bone are found in the marrow, the endosteum, and the periosteum. They contribute to the fracture healing process after injury and...

  9. Muscle-derived stem cells isolated as non-adherent population give rise to cardiac, skeletal muscle and neural lineages

    International Nuclear Information System (INIS)

    Arsic, Nikola; Mamaeva, Daria; Lamb, Ned J.; Fernandez, Anne

    2008-01-01

    Stem cells with the ability to differentiate in specialized cell types can be extracted from a wide array of adult tissues including skeletal muscle. Here we have analyzed a population of cells isolated from skeletal muscle on the basis of their poor adherence on uncoated or collagen-coated dishes that show multi-lineage differentiation in vitro. When analysed under proliferative conditions, these cells express stem cell surface markers Sca-1 (65%) and Bcrp-1 (80%) but also MyoD (15%), Neuronal β III-tubulin (25%), GFAP (30%) or Nkx2.5 (1%). Although capable of growing as non-attached spheres for months, when given an appropriate matrix, these cells adhere giving rise to skeletal muscle, neuronal and cardiac muscle cell lineages. A similar cell population could not be isolated from either bone marrow or cardiac tissue suggesting their specificity to skeletal muscle. When injected into damaged muscle, these non-adherent muscle-derived cells are retrieved expressing Pax7, in a sublaminar position characterizing satellite cells and participate in forming new myofibers. These data show that a non-adherent stem cell population can be specifically isolated and expanded from skeletal muscle and upon attachment to a matrix spontaneously differentiate into muscle, cardiac and neuronal lineages in vitro. Although competing with resident satellite cells, these cells are shown to significantly contribute to repair of injured muscle in vivo supporting that a similar muscle-derived non-adherent cell population from human muscle may be useful in treatment of neuromuscular disorders

  10. Muscle-derived stem cells isolated as non-adherent population give rise to cardiac, skeletal muscle and neural lineages.

    Science.gov (United States)

    Arsic, Nikola; Mamaeva, Daria; Lamb, Ned J; Fernandez, Anne

    2008-04-01

    Stem cells with the ability to differentiate in specialized cell types can be extracted from a wide array of adult tissues including skeletal muscle. Here we have analyzed a population of cells isolated from skeletal muscle on the basis of their poor adherence on uncoated or collagen-coated dishes that show multi-lineage differentiation in vitro. When analysed under proliferative conditions, these cells express stem cell surface markers Sca-1 (65%) and Bcrp-1 (80%) but also MyoD (15%), Neuronal beta III-tubulin (25%), GFAP (30%) or Nkx2.5 (1%). Although capable of growing as non-attached spheres for months, when given an appropriate matrix, these cells adhere giving rise to skeletal muscle, neuronal and cardiac muscle cell lineages. A similar cell population could not be isolated from either bone marrow or cardiac tissue suggesting their specificity to skeletal muscle. When injected into damaged muscle, these non-adherent muscle-derived cells are retrieved expressing Pax7, in a sublaminar position characterizing satellite cells and participate in forming new myofibers. These data show that a non-adherent stem cell population can be specifically isolated and expanded from skeletal muscle and upon attachment to a matrix spontaneously differentiate into muscle, cardiac and neuronal lineages in vitro. Although competing with resident satellite cells, these cells are shown to significantly contribute to repair of injured muscle in vivo supporting that a similar muscle-derived non-adherent cell population from human muscle may be useful in treatment of neuromuscular disorders.

  11. Targeting Cell Polarity Machinery to Exhaust Breast Cancer Stem Cells

    Science.gov (United States)

    2017-10-01

    AWARD NUMBER: W81XWH-15-1-0644 TITLE: Targeting Cell Polarity Machinery to Exhaust Breast Cancer Stem Cells PRINCIPAL INVESTIGATOR: Chun-Ju...Targeting Cell Polarity Machinery to Exhaust Breast Cancer Stem Cells 5a. CONTRACT NUMBER 5b. GRANT NUMBER W81XWH-15-1-0644 5c. PROGRAM ELEMENT...Unlimited 13. SUPPLEMENTARY NOTES 14. ABSTRACT Cancer stem cells (CSCs), a cell population with acquired perpetuating self-renewal properties which

  12. X-ray induced translocations in premeiotic germ cells of monkeys

    International Nuclear Information System (INIS)

    Buul, P.P.W. van

    1991-01-01

    Induction of reciprocal translocations by various X-ray exposures was studied in spermatogonial stem cells of rhesus monkeys (Macaca mulatta) and stump-tailed Macaques (arctoides) by means of spermatocyte analysis many cell generations after irradiation. The yields of trans-locations recovered from irradiated stump-tailed macaques were lower than those observed in rhesus monkeys and represent in fact the lowest induction rates per Gy ever recorded for experimental mammals. In the rhesus monkey a humped dose-effect relationship was found with 1.a homo -geneous response with (pseudo-)linear kinetics below 1 Gy, 2.much more variability at higher doses, and 3.no induction at all at doses of 4 Gy and above. It is suggested that the post-irradiation proliferation differentiation pattern of surviving rhesus monkey spermatogonial stem cells is mainly responsible for these characteristics of the dose-response curve. (author). 41 refs.; 1 fig.; 4 tabs

  13. Exposure of the mouse perinatal testis to radiation leads to hypospermia at sexual maturity

    International Nuclear Information System (INIS)

    Forand, A.; Messiaen, S.; Habert, R.; Bernardino-Sgherri, J.

    2009-01-01

    The first round of mouse spermatogenesis begins from 3 to 4 days after birth through differentiation of gonocytes into spermatogonial-stem cells and type A spermatogonia. Consequently, this step of differentiation may determine generation of the original population of stem cells and the fertility potential of the adult mouse. We aimed to determine the effect of perinatal exposure to ionizing radiation on the testis at the end of the first wave of spermatogenesis and at sexual maturity. Our results show that, radiation sensitivity of the testis substantially decreases from late foetal life to the end of the first week after birth. In addition, partial or full recovery from radiation induced testicular weight loss occurred between the first round of spermatogenesis and sexual maturity, and this was associated with the stimulation of spermatogonial proliferation. Exposure of mice at 17.5 days after conception or at 1 day after birth to γ-rays decreased the sperm counts at sexual maturity, while exposure of 8 day-old mice had no effect. This suggests that irradiation of late foetal or early neonatal testes has a direct impact on the generation of the neonatal spermatogonial-stem cell pool. (authors)

  14. Therapeutic potential of stem cells in auditory hair cell repair

    Directory of Open Access Journals (Sweden)

    Ryuji Hata

    2009-01-01

    Full Text Available The prevalence of acquired hearing loss is very high. About 10% of the total population and more than one third of the population over 65 years suffer from debilitating hearing loss. The most common type of hearing loss in adults is idiopathic sudden sensorineural hearing loss (ISSHL. In the majority of cases, ISSHL is permanent and typically associated with loss of sensory hair cells in the organ of Corti. Following the loss of sensory hair cells, the auditory neurons undergo secondary degeneration. Sensory hair cells and auditory neurons do not regenerate throughout life, and loss of these cells is irreversible and cumulative. However, recent advances in stem cell biology have gained hope that stem cell therapy comes closer to regenerating sensory hair cells in humans. A major advance in the prospects for the use of stem cells to restore normal hearing comes with the recent discovery that hair cells can be generated ex vivo from embryonic stem (ES cells, adult inner ear stem cells and neural stem cells. Furthermore, there is increasing evidence that stem cells can promote damaged cell repair in part by secreting diffusible molecules such as growth factors. These results suggest that stem-cell-based treatment regimens can be applicable to the damaged inner ear as future clinical applications.Previously we have established an animal model of cochlear ischemia in gerbils and showed progressive hair cell loss up to 4 days after ischemia. Auditory brain stem response (ABR recordings have demonstrated that this gerbil model displays severe deafness just after cochlear ischemia and gradually recovers thereafter. These pathological findings and clinical manifestations are reminiscent of ISSHL in humans. In this study, we have shown the effectiveness of stem cell therapy by using this animal model of ISSHL.

  15. Stem Cell Technology in Cardiac Regeneration: A Pluripotent Stem Cell Promise.

    Science.gov (United States)

    Duelen, Robin; Sampaolesi, Maurilio

    2017-02-01

    Despite advances in cardiovascular biology and medical therapy, heart disorders are the leading cause of death worldwide. Cell-based regenerative therapies become a promising treatment for patients affected by heart failure, but also underline the need for reproducible results in preclinical and clinical studies for safety and efficacy. Enthusiasm has been tempered by poor engraftment, survival and differentiation of the injected adult stem cells. The crucial challenge is identification and selection of the most suitable stem cell type for cardiac regenerative medicine. Human pluripotent stem cells (PSCs) have emerged as attractive cell source to obtain cardiomyocytes (CMs), with potential applications, including drug discovery and toxicity screening, disease modelling and innovative cell therapies. Lessons from embryology offered important insights into the development of stem cell-derived CMs. However, the generation of a CM population, uniform in cardiac subtype, adult maturation and functional properties, is highly recommended. Moreover, hurdles regarding tumorigenesis, graft cell death, immune rejection and arrhythmogenesis need to be overcome in clinical practice. Here we highlight the recent progression in PSC technologies for the regeneration of injured heart. We review novel strategies that might overcome current obstacles in heart regenerative medicine, aiming at improving cell survival and functional integration after cell transplantation. Copyright © 2017. Published by Elsevier B.V.

  16. Stem Cell Technology in Cardiac Regeneration: A Pluripotent Stem Cell Promise

    Directory of Open Access Journals (Sweden)

    Robin Duelen

    2017-02-01

    Full Text Available Despite advances in cardiovascular biology and medical therapy, heart disorders are the leading cause of death worldwide. Cell-based regenerative therapies become a promising treatment for patients affected by heart failure, but also underline the need for reproducible results in preclinical and clinical studies for safety and efficacy. Enthusiasm has been tempered by poor engraftment, survival and differentiation of the injected adult stem cells. The crucial challenge is identification and selection of the most suitable stem cell type for cardiac regenerative medicine. Human pluripotent stem cells (PSCs have emerged as attractive cell source to obtain cardiomyocytes (CMs, with potential applications, including drug discovery and toxicity screening, disease modelling and innovative cell therapies. Lessons from embryology offered important insights into the development of stem cell-derived CMs. However, the generation of a CM population, uniform in cardiac subtype, adult maturation and functional properties, is highly recommended. Moreover, hurdles regarding tumorigenesis, graft cell death, immune rejection and arrhythmogenesis need to be overcome in clinical practice. Here we highlight the recent progression in PSC technologies for the regeneration of injured heart. We review novel strategies that might overcome current obstacles in heart regenerative medicine, aiming at improving cell survival and functional integration after cell transplantation.

  17. A computational model incorporating neural stem cell dynamics reproduces glioma incidence across the lifespan in the human population.

    Directory of Open Access Journals (Sweden)

    Roman Bauer

    Full Text Available Glioma is the most common form of primary brain tumor. Demographically, the risk of occurrence increases until old age. Here we present a novel computational model to reproduce the probability of glioma incidence across the lifespan. Previous mathematical models explaining glioma incidence are framed in a rather abstract way, and do not directly relate to empirical findings. To decrease this gap between theory and experimental observations, we incorporate recent data on cellular and molecular factors underlying gliomagenesis. Since evidence implicates the adult neural stem cell as the likely cell-of-origin of glioma, we have incorporated empirically-determined estimates of neural stem cell number, cell division rate, mutation rate and oncogenic potential into our model. We demonstrate that our model yields results which match actual demographic data in the human population. In particular, this model accounts for the observed peak incidence of glioma at approximately 80 years of age, without the need to assert differential susceptibility throughout the population. Overall, our model supports the hypothesis that glioma is caused by randomly-occurring oncogenic mutations within the neural stem cell population. Based on this model, we assess the influence of the (experimentally indicated decrease in the number of neural stem cells and increase of cell division rate during aging. Our model provides multiple testable predictions, and suggests that different temporal sequences of oncogenic mutations can lead to tumorigenesis. Finally, we conclude that four or five oncogenic mutations are sufficient for the formation of glioma.

  18. Myeloproliferative neoplasm stem cells.

    Science.gov (United States)

    Mead, Adam J; Mullally, Ann

    2017-03-23

    Myeloproliferative neoplasms (MPNs) arise in the hematopoietic stem cell (HSC) compartment as a result of the acquisition of somatic mutations in a single HSC that provides a selective advantage to mutant HSC over normal HSC and promotes myeloid differentiation to engender a myeloproliferative phenotype. This population of somatically mutated HSC, which initiates and sustains MPNs, is termed MPN stem cells. In >95% of cases, mutations that drive the development of an MPN phenotype occur in a mutually exclusive manner in 1 of 3 genes: JAK2 , CALR , or MPL The thrombopoietin receptor, MPL, is the key cytokine receptor in MPN development, and these mutations all activate MPL-JAK-STAT signaling in MPN stem cells. Despite common biological features, MPNs display diverse disease phenotypes as a result of both constitutional and acquired factors that influence MPN stem cells, and likely also as a result of heterogeneity in the HSC in which MPN-initiating mutations arise. As the MPN clone expands, it exerts cell-extrinsic effects on components of the bone marrow niche that can favor the survival and expansion of MPN stem cells over normal HSC, further sustaining and driving malignant hematopoiesis. Although developed as targeted therapies for MPNs, current JAK2 inhibitors do not preferentially target MPN stem cells, and as a result, rarely induce molecular remissions in MPN patients. As the understanding of the molecular mechanisms underlying the clonal dominance of MPN stem cells advances, this will help facilitate the development of therapies that preferentially target MPN stem cells over normal HSC. © 2017 by The American Society of Hematology.

  19. Medullospheres from DAOY, UW228 and ONS-76 cells: increased stem cell population and proteomic modifications.

    Science.gov (United States)

    Zanini, Cristina; Ercole, Elisabetta; Mandili, Giorgia; Salaroli, Roberta; Poli, Alice; Renna, Cristiano; Papa, Valentina; Cenacchi, Giovanna; Forni, Marco

    2013-01-01

    Medulloblastoma (MB) is an aggressive pediatric tumor of the Central Nervous System (CNS) usually treated according to a refined risk stratification. The study of cancer stem cells (CSC) in MB is a promising approach aimed at finding new treatment strategies. The CSC compartment was studied in three characterized MB cell lines (DAOY, UW228 and ONS-76) grown in standard adhesion as well as being grown as spheres, which enables expansion of the CSC population. MB cell lines, grown in adherence and as spheres, were subjected to morphologic analysis at the light and electron microscopic level, as well as cytofluorimetric determinations. Medullospheres (MBS) were shown to express increasingly immature features, along with the stem cells markers: CD133, Nestin and β-catenin. Proteomic analysis highlighted the differences between MB cell lines, demonstrating a unique protein profile for each cell line, and minor differences when grown as spheres. In MBS, MALDI-TOF also identified some proteins, that have been linked to tumor progression and resistance, such as Nucleophosmin (NPM). In addition, immunocytochemistry detected Sox-2 as a stemness marker of MBS, as well as confirming high NPM expression. Culture conditioning based on low attachment flasks and specialized medium may provide new data on the staminal compartment of CNS tumors, although a proteomic profile of CSC is still elusive for MB.

  20. Medullospheres from DAOY, UW228 and ONS-76 cells: increased stem cell population and proteomic modifications.

    Directory of Open Access Journals (Sweden)

    Cristina Zanini

    Full Text Available BACKGROUND: Medulloblastoma (MB is an aggressive pediatric tumor of the Central Nervous System (CNS usually treated according to a refined risk stratification. The study of cancer stem cells (CSC in MB is a promising approach aimed at finding new treatment strategies. METHODOLOGY/PRINCIPAL FINDINGS: The CSC compartment was studied in three characterized MB cell lines (DAOY, UW228 and ONS-76 grown in standard adhesion as well as being grown as spheres, which enables expansion of the CSC population. MB cell lines, grown in adherence and as spheres, were subjected to morphologic analysis at the light and electron microscopic level, as well as cytofluorimetric determinations. Medullospheres (MBS were shown to express increasingly immature features, along with the stem cells markers: CD133, Nestin and β-catenin. Proteomic analysis highlighted the differences between MB cell lines, demonstrating a unique protein profile for each cell line, and minor differences when grown as spheres. In MBS, MALDI-TOF also identified some proteins, that have been linked to tumor progression and resistance, such as Nucleophosmin (NPM. In addition, immunocytochemistry detected Sox-2 as a stemness marker of MBS, as well as confirming high NPM expression. CONCLUSIONS/SIGNIFICANCE: Culture conditioning based on low attachment flasks and specialized medium may provide new data on the staminal compartment of CNS tumors, although a proteomic profile of CSC is still elusive for MB.

  1. Characterization of the Stem-Cell Population of Phenylhydrazine-Treated Rodents

    Energy Technology Data Exchange (ETDEWEB)

    Hodgson, G.; Guzman, E.; Herrera, C. [Department of Biology, Vacuity Of Sciences University of Chile, Santiago (Chile)

    1968-08-15

    A study was made of the content of stem cells in the spleen, blood and bone marrow of mice treated with phenylhydrazine; the experimental method used was transplantation in lethally-irradiated mice. There was a marked increase in the content of stem cells in liver and blood and a small increase in bone marrow in the case of animals treated with phenylhydrazine. Judging by the effects of vinblastine, about 80% of the stem cells of spleen pass through mitosis within 24 hours, while only 20% of the marrow cells and none of the blood stem cells pass through mitosis within this period. To obtain information on the average residence time of stem cells in blood, bone marrow was injected intravenously into normal rats and the blood content was determined at intervals, A disappearance half-life of 6 minutes was found. To estimate the increase in the number of stem cells in the spleen of animals treated with phenylhydrazine, rats with and without spleen were irradiated with 500 rad ({sup 137}Cs gamma) after being given five phenylhydrazine injections. The rats without spleen developed severe anaemia with high mortality (70%), compared with the rats with spleen. Among the survivors, erythropoiesis started to recover later and proceeded more slowly in rats that had undergone splenectomy than in those with spleen. Transfusion corrected the anaemia in the rats without spleen and reduced the high mortality, but did not alter the rate of erythropoiesis recovery. The spleen plays an important part in erythropoiesis and the bone-marrow function recovers sooner in rats with spleen than in those without. Although the spleen is important for erythropoiesis recovery after irradiation preceded by treatment with phenylhydrazine, it has no effect on recovery after irradiation alone. It seems as though the spleen is required when proliferation of stem cells at the maximum rate is essential for survival. It is possible that the spleen constitutes a favourable local environment for the

  2. Repeated cisplatin treatment can lead to a multiresistant tumor cell population with stem cell features and sensitivity to 3-bromopyruvate.

    Science.gov (United States)

    Wintzell, My; Löfstedt, Lina; Johansson, Joel; Pedersen, Anne B; Fuxe, Jonas; Shoshan, Maria

    2012-12-01

    Cisplatin is used in treatment of several types of cancer, including epithelial ovarian carcinoma (EOC). In order to mimic clinical treatment and to investigate longterm effects of cisplatin in surviving cancer cells, two EOC cell lines were repeatedly treated with low doses. In the SKOV-3 cell line originating from malignant ascites, but not in A2780 cells from a primary tumor, this led to emergence of a stable population (SKOV-3-R) which in the absence of cisplatin showed increased motility, epithelial-mesenchymal transition (EMT) and expression of cancer stem cell markers CD117, CD44 and ALDH1. Accordingly, the cells formed self-renewing spheres in serum-free stem cell medium. Despite upregulation of mitochondrial mass and cytochrome c, and no upregulation of Bcl-2/Bcl-xL, SKOV-3-R were multiresistant to antineoplastic drugs. Cancer stem cells, or tumor-initiating cells (TICs) are highly chemoresistant and are believed to cause relapse into disseminated and resistant EOC. Our second aim was therefore to target resistance in these TIC-like cells. Resistance could be correlated with upregulation of hexokinase-II and VDAC, which are known to form a survival-promoting mitochondrial complex. The cells were thus sensitive to 3-bromopyruvate, which dissociates hexokinase-II from this complex, and were particularly sensitive to combination treatment with cisplatin at doses down to 0.1 x IC 50. 3-bromopyruvate might thus be of use in targeting the especially aggressive TIC populations.

  3. Transcriptional and functional differences in stem cell populations isolated from Extraocular and Limb muscles

    DEFF Research Database (Denmark)

    Pacheco-Pinedo, Eugenia Cristina; Budak, Murat T; Zeiger, Ulrike

    2008-01-01

    The extraocular muscles (EOMs) are a distinct muscle group that displays an array of unique contractile, structural and regenerative properties. They also have differential sensitivity to certain diseases and are enigmatically spared in Duchenne muscular dystrophy (DMD). The EOMs are so distinct...... from other skeletal muscles that the term: allotype has been coined to highlight EOM-group-specific properties. We hypothesized that increased and distinct stem cells may underlie the continual myogenesis noted in EOM. The side population (SP) stem cells were isolated and studied. EOMs had 15x higher...... SP cell content compared to limb muscles. Expression profiling revealed 348 transcripts that define the EOM-SP transcriptome. Over 92% of transcripts were SP-specific, as they were absent in previous whole-muscle microarray studies. Cultured EOM-SP cells revealed superior in vitro proliferative...

  4. Comparison of human adipose-derived stem cells and bone marrow-derived stem cells in a myocardial infarction model

    DEFF Research Database (Denmark)

    Rasmussen, Jeppe; Frøbert, Ole; Holst-Hansen, Claus

    2014-01-01

    Background: Treatment of myocardial infarction with bone marrow-derived mesenchymal stem cells and recently also adipose-derived stem cells has shown promising results. In contrast to clinical trials and their use of autologous bone marrow-derived cells from the ischemic patient, the animal...... myocardial infarction models are often using young donors and young, often immune-compromised, recipient animals. Our objective was to compare bone marrow-derived mesenchymal stem cells with adipose-derived stem cells from an elderly ischemic patient in the treatment of myocardial infarction, using a fully...... grown non-immunecompromised rat model. Methods: Mesenchymal stem cells were isolated from adipose tissue and bone marrow and compared with respect to surface markers and proliferative capability. To compare the regenerative potential of the two stem cell populations, male Sprague-Dawley rats were...

  5. Endocrine and paracrine regulation of zebrafish spermatogenesis : The Sertoli cell perspective

    NARCIS (Netherlands)

    Schulz, R. W.; Nóbrega, R. H.; Vidal de Souza Morais, Roberto Daltro; De Waal, P. P.; França, L. R.; Bogerd, J.

    2015-01-01

    Spermatogonial stem cells (SSCs) either self-renew or differentiate into spermatogonia that further develop into spermatozoa. Self-renewal occurs when residing in a specific micro-environment (niche) while displacement from the niche would tip the signalling balance towards differentiation.

  6. Stem Cells

    Science.gov (United States)

    Stem cells are cells with the potential to develop into many different types of cells in the body. ... the body. There are two main types of stem cells: embryonic stem cells and adult stem cells. Stem ...

  7. Lin28a is a putative factor in regulating cancer stem cell-like properties in side population cells of oral squamous cell carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Hayashi, S.; Tanaka, J.; Okada, S.; Isobe, T.; Yamamoto, G.; Yasuhara, R.; Irie, T.; Akiyama, C.; Kohno, Y.; Tachikawa, T.; Mishima, K., E-mail: mishima-k@dent.showa-u.ac.jp

    2013-05-01

    Cancer stem cells (CSCs) are among the target cells of cancer therapy because they are uniquely involved in both cancer progression and sensitivity to chemotherapeutic agents. We identified side population (SP) cells, which are known to be an enriched population of CSC, in five oral squamous cell carcinoma (OSCC) cells (SCC9, SCC25, TOSCC7, TOSCC17, and TOSCC23). The percentages of SP cells ranged from 0% to 3.3%, with TOSCC23 cells showing the highest percentages of SP cells (3.3% of the total cell population). The SP cells isolated from TOSCC23 cells also showed greater cell proliferation and invasion compared to non-SP (MP) cells. Therefore, our initial findings suggested that SP cells were enriched for CSC-like cells. Furthermore, DNA microarray analysis revealed that the expression of cell proliferation-related and anti-apoptotic genes was greater in SP cells compared to MP cells. We focused on Lin28a, which showed the highest expression (approximately 22-fold) among the upregulated genes. The overexpression of Lin28a in TOSCC23 cells increased their proliferation, colony formation, and invasion. These findings suggest that Lin28a is an appropriate CSC target molecule for OSCC treatment - Highlights: ► Lin28a is a SP cell-specific factor in oral squamous cell carcinoma (OSCC) cells. ► SP cells in OSCC cells show cancer stem cell-like properties. ► Lin28a regulates OSCC proliferative and invasive activities.

  8. Lin28a is a putative factor in regulating cancer stem cell-like properties in side population cells of oral squamous cell carcinoma

    International Nuclear Information System (INIS)

    Hayashi, S.; Tanaka, J.; Okada, S.; Isobe, T.; Yamamoto, G.; Yasuhara, R.; Irie, T.; Akiyama, C.; Kohno, Y.; Tachikawa, T.; Mishima, K.

    2013-01-01

    Cancer stem cells (CSCs) are among the target cells of cancer therapy because they are uniquely involved in both cancer progression and sensitivity to chemotherapeutic agents. We identified side population (SP) cells, which are known to be an enriched population of CSC, in five oral squamous cell carcinoma (OSCC) cells (SCC9, SCC25, TOSCC7, TOSCC17, and TOSCC23). The percentages of SP cells ranged from 0% to 3.3%, with TOSCC23 cells showing the highest percentages of SP cells (3.3% of the total cell population). The SP cells isolated from TOSCC23 cells also showed greater cell proliferation and invasion compared to non-SP (MP) cells. Therefore, our initial findings suggested that SP cells were enriched for CSC-like cells. Furthermore, DNA microarray analysis revealed that the expression of cell proliferation-related and anti-apoptotic genes was greater in SP cells compared to MP cells. We focused on Lin28a, which showed the highest expression (approximately 22-fold) among the upregulated genes. The overexpression of Lin28a in TOSCC23 cells increased their proliferation, colony formation, and invasion. These findings suggest that Lin28a is an appropriate CSC target molecule for OSCC treatment - Highlights: ► Lin28a is a SP cell-specific factor in oral squamous cell carcinoma (OSCC) cells. ► SP cells in OSCC cells show cancer stem cell-like properties. ► Lin28a regulates OSCC proliferative and invasive activities

  9. Endogenous, very small embryonic-like stem cells: critical review, therapeutic potential and a look ahead.

    Science.gov (United States)

    Bhartiya, Deepa; Shaikh, Ambreen; Anand, Sandhya; Patel, Hiren; Kapoor, Sona; Sriraman, Kalpana; Parte, Seema; Unni, Sreepoorna

    2016-12-01

    Both pluripotent very small embryonic-like stem cells (VSELs) and induced pluripotent stem (iPS) cells were reported in 2006. In 2012, a Nobel Prize was awarded for iPS technology whereas even today the very existence of VSELs is not well accepted. The underlying reason is that VSELs exist in low numbers, remain dormant under homeostatic conditions, are very small in size and do not pellet down at 250-280g. The VSELs maintain life-long tissue homeostasis, serve as a backup pool for adult stem cells and are mobilized under stress conditions. An imbalance in VSELs function (uncontrolled proliferation) may result in cancer. The electronic database 'Medline/Pubmed' was systematically searched with the subject heading term 'very small embryonic-like stem cells'. The most primitive stem cells that undergo asymmetric cell divisions to self-renew and give rise to progenitors still remain elusive in the hematopoietic system and testes, while the presence of stem cells in ovary is still being debated. We propose to review the available literature on VSELs, the methods of their isolation and characterization, their ontogeny, how they compare with embryonic stem (ES) cells, primordial germ cells (PGCs) and iPS cells, and their role in maintaining tissue homeostasis. The review includes a look ahead on how VSELs will result in paradigm shifts in basic reproductive biology. Adult tissue-specific stem cells including hematopoietic, spermatogonial, ovarian and mesenchymal stem cells have good proliferation potential and are indeed committed progenitors (with cytoplasmic OCT-4), which arise by asymmetric cell divisions of pluripotent VSELs (with nuclear OCT-4). VSELs are the most primitive stem cells and postulated to be an overlapping population with the PGCs. Rather than migrating only to the gonads, PGCs migrate and survive in various adult body organs throughout life as VSELs. VSELs express both pluripotent and PGC-specific markers and are epigenetically and developmentally

  10. Adipogenic placenta-derived mesenchymal stem cells are not lineage restricted by withdrawing extrinsic factors: developing a novel visual angle in stem cell biology.

    Science.gov (United States)

    Hu, C; Cao, H; Pan, X; Li, J; He, J; Pan, Q; Xin, J; Yu, X; Li, J; Wang, Y; Zhu, D; Li, L

    2016-03-17

    Current evidence implies that differentiated bone marrow mesenchymal stem cells (BMMSCs) can act as progenitor cells and transdifferentiate across lineage boundaries. However, whether this unrestricted lineage has specificities depending on the stem cell type is unknown. Placental-derived mesenchymal stem cells (PDMSCs), an easily accessible and less invasive source, are extremely useful materials in current stem cell therapies. No studies have comprehensively analyzed the transition in morphology, surface antigens, metabolism and multilineage potency of differentiated PDMSCs after their dedifferentiation. In this study, we showed that after withdrawing extrinsic factors, adipogenic PDMSCs reverted to a primitive cell population and retained stem cell characteristics. The mitochondrial network during differentiation and dedifferentiation may serve as a marker of absent or acquired pluripotency in various stem cell models. The new population proliferated faster than unmanipulated PDMSCs and could be differentiated into adipocytes, osteocytes and hepatocytes. The cell adhesion molecules (CAMs) signaling pathway and extracellular matrix (ECM) components modulate cell behavior and enable the cells to proliferate or differentiate during the differentiation, dedifferentiation and redifferentiation processes in our study. These observations indicate that the dedifferentiated PDMSCs are distinguishable from the original PDMSCs and may serve as a novel source in stem cell biology and cell-based therapeutic strategies. Furthermore, whether PDMSCs differentiated into other lineages can be dedifferentiated to a primitive cell population needs to be investigated.

  11. Strategies for future histocompatible stem cell therapy

    DEFF Research Database (Denmark)

    Nehlin, Jan; Barington, Torben

    2009-01-01

    Stem cell therapy based on the safe and unlimited self-renewal of human pluripotent stem cells is envisioned for future use in tissue or organ replacement after injury or disease. A gradual decline of regenerative capacity has been documented among the adult stem cell population in some body organs...... during the aging process. Recent progress in human somatic cell nuclear transfer and inducible pluripotent stem cell technologies has shown that patient-derived nuclei or somatic cells can be reprogrammed in vitro to become pluripotent stem cells, from which the three germ layer lineages can be generated......, genetically identical to the recipient. Once differentiation protocols and culture conditions can be defined and optimized, patient-histocompatible pluripotent stem cells could be directed towards virtually every cell type in the human body. Harnessing this capability to enrich for given cells within...

  12. Role of bone marrow-derived stem cells, renal progenitor cells and stem cell factor in chronic renal allograft nephropathy

    OpenAIRE

    Hayam Abdel Meguid El Aggan; Mona Abdel Kader Salem; Nahla Mohamed Gamal Farahat; Ahmad Fathy El-Koraie; Ghaly Abd Al-Rahim Mohammed Kotb

    2013-01-01

    Introduction: Chronic allograft nephropathy (CAN) is a poorly understood clinico-pathological entity associated with chronic allograft loss due to immunologic and non-immunologic causes. It remains the leading cause of late allograft loss. Bone marrow derived stem cells are undifferentiated cells typically characterized by their capacity for self renewal, ability to give rise to multiple differentiated cellular population, including hematopoietic (HSCs) and mesenchymal stem cells (MSCs). Char...

  13. Ionizing radiation induces stemness in cancer cells.

    Directory of Open Access Journals (Sweden)

    Laura Ghisolfi

    Full Text Available The cancer stem cell (CSC model posits the presence of a small number of CSCs in the heterogeneous cancer cell population that are ultimately responsible for tumor initiation, as well as cancer recurrence and metastasis. CSCs have been isolated from a variety of human cancers and are able to generate a hierarchical and heterogeneous cancer cell population. CSCs are also resistant to conventional chemo- and radio-therapies. Here we report that ionizing radiation can induce stem cell-like properties in heterogeneous cancer cells. Exposure of non-stem cancer cells to ionizing radiation enhanced spherogenesis, and this was accompanied by upregulation of the pluripotency genes Sox2 and Oct3/4. Knockdown of Sox2 or Oct3/4 inhibited radiation-induced spherogenesis and increased cellular sensitivity to radiation. These data demonstrate that ionizing radiation can activate stemness pathways in heterogeneous cancer cells, resulting in the enrichment of a CSC subpopulation with higher resistance to radiotherapy.

  14. Individual fates of mesenchymal stem cells in vitro

    Directory of Open Access Journals (Sweden)

    Drasdo Dirk

    2010-05-01

    Full Text Available Abstract Background In vitro cultivated stem cell populations are in general heterogeneous with respect to their expression of differentiation markers. In hematopoietic progenitor populations, this heterogeneity has been shown to regenerate within days from isolated subpopulations defined by high or low marker expression. This kind of plasticity has been suggested to be a fundamental feature of mesenchymal stem cells (MSCs as well. Here, we study MSC plasticity on the level of individual cells applying a multi-scale computer model that is based on the concept of noise-driven stem cell differentiation. Results By simulation studies, we provide detailed insight into the kinetics of MSC organisation. Monitoring the fates of individual cells in high and low oxygen culture, we calculated the average transition times of individual cells into stem cell and differentiated states. We predict that at low oxygen the heterogeneity of a MSC population with respect to differentiation regenerates from any selected subpopulation in about two days. At high oxygen, regeneration becomes substantially slowed down. Simulation results on the composition of the functional stem cell pool of MSC populations suggest that most of the cells that constitute this pool originate from more differentiated cells. Conclusions Individual cell-based models are well-suited to provide quantitative predictions on essential features of the spatio-temporal organisation of MSC in vitro. Our predictions on MSC plasticity and its dependence on the environment motivate a number of in vitro experiments for validation. They may contribute to a better understanding of MSC organisation in vitro, including features of clonal expansion, environmental adaptation and stem cell ageing.

  15. Effect of dedifferentiation on time to mutation acquisition in stem cell-driven cancers.

    Directory of Open Access Journals (Sweden)

    Alexandra Jilkine

    2014-03-01

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

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

    Science.gov (United States)

    Jilkine, Alexandra; Gutenkunst, Ryan N.

    2014-01-01

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

  17. A novel rat fibrosarcoma cell line from transformed bone marrow-derived mesenchymal stem cells with maintained in vitro and in vivo stemness properties

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Meng-Yu [Department of Cell Therapy, Institute for Cancer Research, Oslo University Hospital, Oslo (Norway); Nestvold, Janne, E-mail: j.m.nestvold@medisin.uio.no [Department of Molecular Medicine, Institute of Basic Medical Sciences, University of Oslo (Norway); Rekdal, Øystein [Department of Medical Biology, Faculty of Health Sciences, UiT The Arctic University of Norway, Tromsø (Norway); Kvalheim, Gunnar [Department of Cell Therapy, Institute for Cancer Research, Oslo University Hospital, Oslo (Norway); Fodstad, Øystein [Department of Tumor Biology, Institute for Cancer Research, Oslo University Hospital, Oslo (Norway)

    2017-03-15

    Increasing evidence suggests a possible relationship between mesenchymal stem cells (MSCs) and sarcoma. MSCs are hypothesized to be the cells initiating sarcomagenesis, and cancer stem cells (CSCs) sharing features of MSCs have been identified in sarcomas. Here, we report on the characteristics of a bone marrow-derived rat mesenchymal stem cell line that spontaneously transformed in long-term culture. The rat transformed mesenchymal stem cells (rTMSCs) produced soft-tissue fibrosarcomas in immunocompromised mice and immunocompetent rats. In vitro, the rTMSCs displayed increased proliferation capacity compared to the untransformed cell line. The transformed MSCs maintained the mesenchymal phenotype by expression of the stem cell marker CD 90 and the lack of hematopoietic and endothelial markers. Cytogenetic analysis detected trisomy 6 in the rTMSCs. Side population (SP) isolation and tumorsphere cultivation of the transformed cells confirmed the presence of CSCs among the rTMSCs. Importantly, the rTMSCs retained their differentiation capacity towards osteogenic and adipogenic lineages. This transformed MSC-based cell line may be valuable in examining the balance in a mixed cell population between cancer stem cell properties and the ability to differentiate to specific non-transformed cell populations. Moreover, it may also be a useful tool to evaluate the efficacy of novel targeted immunotherapies in vivo. - Highlights: • Spontaneously transformed rat MSCs (rTMSCs) share characteristics with normal MSCs. • rTMSCs possess a side population, enriched with tumorigenic cells. • rTMSCs model fibrosarcoma in vivo.

  18. A novel rat fibrosarcoma cell line from transformed bone marrow-derived mesenchymal stem cells with maintained in vitro and in vivo stemness properties

    International Nuclear Information System (INIS)

    Wang, Meng-Yu; Nestvold, Janne; Rekdal, Øystein; Kvalheim, Gunnar; Fodstad, Øystein

    2017-01-01

    Increasing evidence suggests a possible relationship between mesenchymal stem cells (MSCs) and sarcoma. MSCs are hypothesized to be the cells initiating sarcomagenesis, and cancer stem cells (CSCs) sharing features of MSCs have been identified in sarcomas. Here, we report on the characteristics of a bone marrow-derived rat mesenchymal stem cell line that spontaneously transformed in long-term culture. The rat transformed mesenchymal stem cells (rTMSCs) produced soft-tissue fibrosarcomas in immunocompromised mice and immunocompetent rats. In vitro, the rTMSCs displayed increased proliferation capacity compared to the untransformed cell line. The transformed MSCs maintained the mesenchymal phenotype by expression of the stem cell marker CD 90 and the lack of hematopoietic and endothelial markers. Cytogenetic analysis detected trisomy 6 in the rTMSCs. Side population (SP) isolation and tumorsphere cultivation of the transformed cells confirmed the presence of CSCs among the rTMSCs. Importantly, the rTMSCs retained their differentiation capacity towards osteogenic and adipogenic lineages. This transformed MSC-based cell line may be valuable in examining the balance in a mixed cell population between cancer stem cell properties and the ability to differentiate to specific non-transformed cell populations. Moreover, it may also be a useful tool to evaluate the efficacy of novel targeted immunotherapies in vivo. - Highlights: • Spontaneously transformed rat MSCs (rTMSCs) share characteristics with normal MSCs. • rTMSCs possess a side population, enriched with tumorigenic cells. • rTMSCs model fibrosarcoma in vivo.

  19. Stem cell self-renewal in intestinal crypt

    International Nuclear Information System (INIS)

    Simons, Benjamin D.; Clevers, Hans

    2011-01-01

    As a rapidly cycling tissue capable of fast repair and regeneration, the intestinal epithelium has emerged as a favored model system to explore the principles of adult stem cell biology. However, until recently, the identity and characteristics of the stem cell population in both the small intestine and colon has remained the subject of debate. Recent studies based on targeted lineage tracing strategies, combined with the development of an organotypic culture system, have identified the crypt base columnar cell as the intestinal stem cell, and have unveiled the strategy by which the balance between proliferation and differentiation is maintained. These results show that intestinal stem cells operate in a dynamic environment in which frequent and stochastic stem cell loss is compensated by the proliferation of neighboring stem cells. We review the basis of these experimental findings and the insights they offer into the mechanisms of homeostatic stem cell regulation.

  20. Stem cells and cancer: A review

    Directory of Open Access Journals (Sweden)

    Najeeb Ullah

    2016-05-01

    Full Text Available Stem cells are the small units of multicellular creature. Regeneration and self-renewal are the ability of the stem cells. Each tissue is having particular stem cells, specific to it. These normal stem cells are converted into cancer stem cells through mutations in it. Although the expression of oncogenes is enhanced a lot, the tumor-supressing gene is lessened. Cancer stem cells are isolated and visualized through different techniques like immunocytochemical staining, spectral karyotyping, immunohistochemistry, induction method and dissection measures, then are performed histological procedures which include fascination, immunohistochemistry, dispensation, in situ hybridization and also quantitative examination of tissue flow cytometric analysis. For the analysis of quantization, statistical tests are also performed as two-sample t-test, Chi-square test, SD and arithmetic mean. Tumor cells generate glioma spheres. These are used in cancer study. Axin 1 is the gene suppressing cancer. Its removal causes the generation of liver cancer. Curcumin is the most effective for suppressing cancer as it increases the normal stem cell function and decreases the cancer stem cell function. Brahma-related gene 1 is crucial for the safeguarding of the stem cell residents in tissue-specific comportment. Different types of cancers originate through genetic mutation, tissue disorganization and cell proliferation. Tumor configuration is produced by the alteration in original cell culture having stem cells and progenitor cell populations. The developmental facets about cancer cells and cancer stem cells as well as their personal natal functions sustain an intricate steadiness to settle on their personal donations to the efficacy or harmfulness of the biological organization.

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

    International Nuclear Information System (INIS)

    Hyun, Kyung-Hwan; Yoon, Chang-Hwan; Kim, Rae-Kwon; Lim, Eun-Jung; An, Sungkwan; Park, Myung-Jin; Hyun, Jin-Won; Suh, Yongjoon; Kim, Min-Jung; Lee, Su-Jae

    2011-01-01

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

  2. Involvement of plant stem cells or stem cell-like cells in dedifferentiation

    Directory of Open Access Journals (Sweden)

    Fangwei eJiang

    2015-11-01

    Full Text Available 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.

  3. Differentiation of embryonic stem cells towards hematopoietic cells: progress and pitfalls.

    Science.gov (United States)

    Tian, Xinghui; Kaufman, Dan S

    2008-07-01

    Hematopoietic development from embryonic stem cells has been one of the most productive areas of stem cell biology. Recent studies have progressed from work with mouse to human embryonic stem cells. Strategies to produce defined blood cell populations can be used to better understand normal and abnormal hematopoiesis, as well as potentially improve the generation of hematopoietic cells with therapeutic potential. Molecular profiling, phenotypic and functional analyses have all been utilized to demonstrate that hematopoietic cells derived from embryonic stem cells most closely represent a stage of hematopoiesis that occurs at embryonic/fetal developmental stages. Generation of hematopoietic stem/progenitor cells comparable to hematopoietic stem cells found in the adult sources, such as bone marrow and cord blood, still remains challenging. However, genetic manipulation of intrinsic factors during hematopoietic differentiation has proven a suitable approach to induce adult definitive hematopoiesis from embryonic stem cells. Concrete evidence has shown that embryonic stem cells provide a powerful approach to study the early stage of hematopoiesis. Multiple hematopoietic lineages can be generated from embryonic stem cells, although most of the evidence suggests that hematopoietic development from embryonic stem cells mimics an embryonic/fetal stage of hematopoiesis.

  4. Composition of Mineral Produced by Dental Mesenchymal Stem Cells.

    Science.gov (United States)

    Volponi, A A; Gentleman, E; Fatscher, R; Pang, Y W Y; Gentleman, M M; Sharpe, P T

    2015-11-01

    Mesenchymal stem cells isolated from different dental tissues have been described to have osteogenic/odontogenic-like differentiation capacity, but little attention has been paid to the biochemical composition of the material that each produces. Here, we used Raman spectroscopy to analyze the mineralized materials produced in vitro by different dental cell populations, and we compared them with the biochemical composition of native dental tissues. We show that different dental stem cell populations produce materials that differ in their mineral and matrix composition and that these differ from those of native dental tissues. In vitro, BCMP (bone chip mass population), SCAP (stem cells from apical papilla), and SHED (stem cells from human-exfoliated deciduous teeth) cells produce a more highly mineralized matrix when compared with that produced by PDL (periodontal ligament), DPA (dental pulp adult), and GF (gingival fibroblast) cells. Principal component analyses of Raman spectra further demonstrated that the crystallinity and carbonate substitution environments in the material produced by each cell type varied, with DPA cells, for example, producing a more carbonate-substituted mineral and with SCAP, SHED, and GF cells creating a less crystalline material when compared with other dental stem cells and native tissues. These variations in mineral composition reveal intrinsic differences in the various cell populations, which may in turn affect their specific clinical applications. © International & American Associations for Dental Research 2015.

  5. Discovery of Power-Law Growth in the Self-Renewal of Heterogeneous Glioma Stem Cell Populations.

    Directory of Open Access Journals (Sweden)

    Michiya Sugimori

    Full Text Available Accumulating evidence indicates that cancer stem cells (CSCs drive tumorigenesis. This suggests that CSCs should make ideal therapeutic targets. However, because CSC populations in tumors appear heterogeneous, it remains unclear how CSCs might be effectively targeted. To investigate the mechanisms by which CSC populations maintain heterogeneity during self-renewal, we established a glioma sphere (GS forming model, to generate a population in which glioma stem cells (GSCs become enriched. We hypothesized, based on the clonal evolution concept, that with each passage in culture, heterogeneous clonal sublines of GSs are generated that progressively show increased proliferative ability.To test this hypothesis, we determined whether, with each passage, glioma neurosphere culture generated from four different glioma cell lines become progressively proliferative (i.e., enriched in large spheres. Rather than monitoring self-renewal, we measured heterogeneity based on neurosphere clone sizes (#cells/clone. Log-log plots of distributions of clone sizes yielded a good fit (r>0.90 to a straight line (log(% total clones = k*log(#cells/clone indicating that the system follows a power-law (y = xk with a specific degree exponent (k = -1.42. Repeated passaging of the total GS population showed that the same power-law was maintained over six passages (CV = -1.01 to -1.17. Surprisingly, passage of either isolated small or large subclones generated fully heterogeneous populations that retained the original power-law-dependent heterogeneity. The anti-GSC agent Temozolomide, which is well known as a standard therapy for glioblastoma multiforme (GBM, suppressed the self-renewal of clones, but it never disrupted the power-law behavior of a GS population.Although the data above did not support the stated hypothesis, they did strongly suggest a novel mechanism that underlies CSC heterogeneity. They indicate that power-law growth governs the self-renewal of heterogeneous

  6. Genetically induced cell death in bulge stem cells reveals their redundancy for hair and epidermal regeneration.

    Science.gov (United States)

    Driskell, Iwona; Oeztuerk-Winder, Feride; Humphreys, Peter; Frye, Michaela

    2015-03-01

    Adult mammalian epidermis contains multiple stem cell populations in which quiescent and more proliferative stem and progenitor populations coexist. However, the precise interrelation of these populations in homeostasis remains unclear. Here, we blocked the contribution of quiescent keratin 19 (K19)-expressing bulge stem cells to hair follicle formation through genetic ablation of the essential histone methyltransferase Setd8 that is required for the maintenance of adult skin. Deletion of Setd8 eliminated the contribution of bulge cells to hair follicle regeneration through inhibition of cell division and induction of cell death, but the growth and morphology of hair follicles were unaffected. Furthermore, ablation of Setd8 in the hair follicle bulge blocked the contribution of K19-postive stem cells to wounded epidermis, but the wound healing process was unaltered. Our data indicate that quiescent bulge stem cells are dispensable for hair follicle regeneration and epidermal injury in the short term and support the hypothesis that quiescent and cycling stem cell populations are equipotent. © 2014 AlphaMed Press.

  7. Cellular and molecular biology of the prostate: stem cell biology.

    NARCIS (Netherlands)

    Schalken, J.A.; Leenders, G.J.L.H. van

    2003-01-01

    The normal prostate shows a high degree of cellular organization. The basal layer is populated by prostate epithelial stem cells and a population of transiently proliferating/amplifying (TP/A) cells intermediate to the stem cells and fully differentiated cells. The luminal layer is composed of fully

  8. The Bile Acid Nuclear Receptor FXRα Is a Critical Regulator of Mouse Germ Cell Fate

    Directory of Open Access Journals (Sweden)

    Emmanuelle Martinot

    2017-07-01

    Full Text Available Spermatogenesis is the process by which spermatozoa are generated from spermatogonia. This cell population is heterogeneous, with self-renewing spermatogonial stem cells (SSCs and progenitor spermatogonia that will continue on a path of differentiation. Only SSCs have the ability to regenerate and sustain spermatogenesis. This makes the testis a good model to investigate stem cell biology. The Farnesoid X Receptor alpha (FXRα was recently shown to be expressed in the testis. However, its global impact on germ cell homeostasis has not yet been studied. Here, using a phenotyping approach in Fxrα−/− mice, we describe unexpected roles of FXRα on germ cell physiology independent of its effects on somatic cells. FXRα helps establish and maintain an undifferentiated germ cell pool and in turn influences male fertility. FXRα regulates the expression of several pluripotency factors. Among these, in vitro approaches show that FXRα controls the expression of the pluripotency marker Lin28 in the germ cells.

  9. Role of bone marrow-derived stem cells, renal progenitor cells and ...

    African Journals Online (AJOL)

    It remains the leading cause of late allograft loss. Bone marrow derived stem cells are undifferentiated cells typically characterized by their capacity for self renewal, ability to give rise to multiple differentiated cellular population, including hematopoietic (HSCs) and mesenchymal stem cells (MSCs). Characterization of HSCs ...

  10. Estimation of the target stem-cell population size in chronic myeloid leukemogenesis

    International Nuclear Information System (INIS)

    Radivoyevitch, T.; Ramsey, M.J.; Tucker, J.D.

    1999-01-01

    Estimation of the number of hematopoietic stem cells capable of causing chronic myeloid leukemia (CML) is relevant to the development of biologically based risk models of radiation-induced CML. Through a comparison of the age structure of CML incidence data from the Surveillance, Epidemiology, and End Results (SEER) Program and the age structure of chromosomal translocations found in healthy subjects, the number of CML target stem cells is estimated for individuals above 20 years of age. The estimation involves three steps. First, CML incidence among adults is fit to an exponentially increasing function of age. Next, assuming a relatively short waiting time distribution between BCR-ABL induction and the appearance of CML, an exponential age function with rate constants fixed to the values found for CML is fitted to the translocation data. Finally, assuming that translocations are equally likely to occur between any two points in the genome, the parameter estimates found in the first two steps are used to estimate the number of target stem cells for CML. The population-averaged estimates of this number are found to be 1.86 x 10 8 for men and 1.21 x 10 8 for women; the 95% confidence intervals of these estimates are (1.34 x 10 8 , 2.50 x 10 8 ) and (0.84 x 10 8 , 1.83 x 10 8 ), respectively. (orig.)

  11. A functional model for adult stem cells in epithelial tissues.

    NARCIS (Netherlands)

    Verstappen, J.; Katsaros, C.; Torensma, R.; Hoff, J.W. Von den

    2009-01-01

    Tissue turnover, regeneration, and repair take place throughout life. Stem cells are key players in these processes. The characteristics and niches of the stem cell populations in different tissues, and even in related tissues, vary extensively. In this review, stem cell differentiation and stem

  12. Transplantation? Peripheral Stem Cell/Bone Marrow/Cord Blood

    Directory of Open Access Journals (Sweden)

    Itır Sirinoglu Demiriz

    2012-01-01

    Full Text Available The introduction of peripheral stem cell (PSC and cord blood (CB as an alternative to bone marrow (BM recently has caused important changes on hematopoietic stem cell transplantation (HSCT practice. According to the CIBMTR data, there has been a significant decrease in the use of bone marrow and increase in the use of PSC and CB as the stem cell source for HSCT performed during 1997–2006 period for patients under the age of 20. On the other hand, the stem cell source in 70% of the HSCT procedures performed for patients over the age of 20 was PSC and the second most preferred stem cell source was bone marrow. CB usage is very limited for the adult population. Primary disease, stage, age, time and urgency of transplantation, HLA match between the patient and the donor, stem cell quantity, and the experience of the transplantation center are some of the associated factors for the selection of the appropriate stem cell source. Unfortunately, there is no prospective randomized study aimed to facilitate the selection of the correct source between CB, PSC, and BM. In this paper, we would like to emphasize the data on stem cell selection in light of the current knowledge for patient populations according to their age and primary disease.

  13. Stem cell technology for drug discovery and development.

    Science.gov (United States)

    Hook, Lilian A

    2012-04-01

    Stem cells have enormous potential to revolutionise the drug discovery process at all stages, from target identification through to toxicology studies. Their ability to generate physiologically relevant cells in limitless supply makes them an attractive alternative to currently used recombinant cell lines or primary cells. However, realisation of the full potential of stem cells is currently hampered by the difficulty in routinely directing stem cell differentiation to reproducibly and cost effectively generate pure populations of specific cell types. In this article we discuss how stem cells have already been used in the drug discovery process and how novel technologies, particularly in relation to stem cell differentiation, can be applied to attain widespread adoption of stem cell technology by the pharmaceutical industry. Copyright © 2011 Elsevier Ltd. All rights reserved.

  14. Nonclinical safety strategies for stem cell therapies

    Energy Technology Data Exchange (ETDEWEB)

    Sharpe, Michaela E., E-mail: michaela_sharpe@yahoo.com [Investigative Toxicology, Drug Safety Research and Development, Pfizer Ltd, Ramsgate Road, Sandwich, CT13 9NJ (United Kingdom); Morton, Daniel [Exploratory Drug Safety, Drug Safety Research and Development, Pfizer Inc, Cambridge, 02140 (United States); Rossi, Annamaria [Investigative Toxicology, Drug Safety Research and Development, Pfizer Ltd, Ramsgate Road, Sandwich, CT13 9NJ (United Kingdom)

    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.

  15. Nonclinical safety strategies for stem cell therapies

    International Nuclear Information System (INIS)

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

    2012-01-01

    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.

  16. Update on small intestinal stem cells.

    Science.gov (United States)

    Tesori, Valentina; Puglisi, Maria Ausiliatrice; Lattanzi, Wanda; Gasbarrini, Giovanni Battista; Gasbarrini, Antonio

    2013-08-07

    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.

  17. Intrinsically active and pacemaker neurons in pluripotent stem cell-derived neuronal populations.

    Science.gov (United States)

    Illes, Sebastian; Jakab, Martin; Beyer, Felix; Gelfert, Renate; Couillard-Despres, Sébastien; Schnitzler, Alfons; Ritter, Markus; Aigner, Ludwig

    2014-03-11

    Neurons generated from pluripotent stem cells (PSCs) self-organize into functional neuronal assemblies in vitro, generating synchronous network activities. Intriguingly, PSC-derived neuronal assemblies develop spontaneous activities that are independent of external stimulation, suggesting the presence of thus far undetected intrinsically active neurons (IANs). Here, by using mouse embryonic stem cells, we provide evidence for the existence of IANs in PSC-neuronal networks based on extracellular multielectrode array and intracellular patch-clamp recordings. IANs remain active after pharmacological inhibition of fast synaptic communication and possess intrinsic mechanisms required for autonomous neuronal activity. PSC-derived IANs are functionally integrated in PSC-neuronal populations, contribute to synchronous network bursting, and exhibit pacemaker properties. The intrinsic activity and pacemaker properties of the neuronal subpopulation identified herein may be particularly relevant for interventions involving transplantation of neural tissues. IANs may be a key element in the regulation of the functional activity of grafted as well as preexisting host neuronal networks.

  18. Primer and interviews: The dynamic stem cell niche.

    Science.gov (United States)

    Kiefer, Julie C

    2011-03-01

    A stem cell niche is a microenvironment that supports self-renewal of a population of stem cells, and their production of differentiated cells. While the definition evokes images of a stem cell Shangri-La-where a serene stem cell pool nestles within a niche that shelters and sustains it-the reality is much more tumultuous. Niches are subject to an ever-changing maelstrom of environmental factors, the ravages of old age, and the sly tactics of disease. Presented here is a basic overview of the different ways in which stem cell niches respond to local and systemic environments, and their impact on stem cell behavior. The primer culminates with a discussion of the topic with stem cell and niche biologists D. Leanne Jones, Ph.D., and Tudorita Tumbar, Ph.D. Copyright © 2011 Wiley-Liss, Inc.

  19. Stem cells in dentistry--part I: stem cell sources.

    Science.gov (United States)

    Egusa, Hiroshi; Sonoyama, Wataru; Nishimura, Masahiro; Atsuta, Ikiru; Akiyama, Kentaro

    2012-07-01

    Stem cells can self-renew and produce different cell types, thus providing new strategies to regenerate missing tissues and treat diseases. In the field of dentistry, adult mesenchymal stem/stromal cells (MSCs) have been identified in several oral and maxillofacial tissues, which suggests that the oral tissues are a rich source of stem cells, and oral stem and mucosal cells are expected to provide an ideal source for genetically reprogrammed cells such as induced pluripotent stem (iPS) cells. Furthermore, oral tissues are expected to be not only a source but also a therapeutic target for stem cells, as stem cell and tissue engineering therapies in dentistry continue to attract increasing clinical interest. Part I of this review outlines various types of intra- and extra-oral tissue-derived stem cells with regard to clinical availability and applications in dentistry. Additionally, appropriate sources of stem cells for regenerative dentistry are discussed with regard to differentiation capacity, accessibility and possible immunomodulatory properties. Copyright © 2012 Japan Prosthodontic Society. Published by Elsevier Ltd. All rights reserved.

  20. Heterogeneity and plasticity of epidermal stem cells

    DEFF Research Database (Denmark)

    Schepeler, Troels; Page, Mahalia E; Jensen, Kim Bak

    2014-01-01

    The epidermis is an integral part of our largest organ, the skin, and protects us against the hostile environment. It is a highly dynamic tissue that, during normal steady-state conditions, undergoes constant turnover. Multiple stem cell populations residing in autonomously maintained compartments...... facilitate this task. In this Review, we discuss stem cell behaviour during normal tissue homeostasis, regeneration and disease within the pilosebaceous unit, an integral structure of the epidermis that is responsible for hair growth and lubrication of the epithelium. We provide an up-to-date view...... of the pilosebaceous unit, encompassing the heterogeneity and plasticity of multiple discrete stem cell populations that are strongly influenced by external cues to maintain their identity and function....

  1. Cellular Mechanisms of Somatic Stem Cell Aging

    Science.gov (United States)

    Jung, Yunjoon

    2014-01-01

    Tissue homeostasis and regenerative capacity rely on rare populations of somatic stem cells endowed with the potential to self-renew and differentiate. During aging, many tissues show a decline in regenerative potential coupled with a loss of stem cell function. Cells including somatic stem cells have evolved a series of checks and balances to sense and repair cellular damage to maximize tissue function. However, during aging the mechanisms that protect normal cell function begin to fail. In this review, we will discuss how common cellular mechanisms that maintain tissue fidelity and organismal lifespan impact somatic stem cell function. We will highlight context-dependent changes and commonalities that define aging, by focusing on three age-sensitive stem cell compartments: blood, neural, and muscle. Understanding the interaction between extrinsic regulators and intrinsic effectors that operate within different stem cell compartments is likely to have important implications for identifying strategies to improve health span and treat age-related degenerative diseases. PMID:24439814

  2. p38 MAPK pathway is essential for self-renewal of mouse male germline stem cells (mGSCs).

    Science.gov (United States)

    Niu, Zhiwei; Mu, Hailong; Zhu, Haijing; Wu, Jiang; Hua, Jinlian

    2017-02-01

    Male germline stem cells (mGSCs), also called spermatogonial stem cells (SSCs), constantly generate spermatozoa in male animals. A number of preliminary studies on mechanisms of mGSC self-renewal have previously been conducted, revealing that several factors are involved in this regulated process. The p38 MAPK pathway is widely conserved in multiple cell types in vivo, and plays an important role in cell proliferation, differentiation, inflammation and apoptosis. However, its role in self-renewal of mGSCs has not hitherto been determined. Here, the mouse mGSCs were cultured and their identity was verified by semi-RT-PCR, alkaline phosphatase (AP) staining and immunofluorescence staining. Then, the p38 MAPK pathway was blocked by p38 MAPK-specific inhibitor SB202190. mGSC self-renewal ability was then analysed by observation of morphology, cell number, cell growth analysis, TUNEL incorporation assay and cell cycle analysis. Results showed that mouse mGSC self-renewal ability was significantly inhibited by SB202190. This study showed for the first time that the p38 MAPK pathway plays a key role in maintaining self-renewal capacity of mouse mGSCs, which offers a new self-renewal pathway for these cells and contributes to overall knowledge of the mechanisms of mGSC self-renewal. © 2016 John Wiley & Sons Ltd.

  3. Identification of cancer stem-like side population cells in purified primary cultured human laryngeal squamous cell carcinoma epithelia.

    Directory of Open Access Journals (Sweden)

    Chun-Ping Wu

    Full Text Available Cancer stem-like side population (SP cells have been identified in many solid tumors; however, most of these investigations are performed using established cancer cell lines. Cancer cells in tumor tissue containing fibroblasts and many other types of cells are much more complex than any cancer cell line. Although SP cells were identified in the laryngeal squamous cell carcinoma (LSCC cell line Hep-2 in our pilot study, it is unknown whether the LSCC tissue contains SP cells. In this study, LSCC cells (LSCCs were primary cultured and purified from a surgically resected LSCC specimen derived from a well-differentiated epiglottic neoplasm of a Chinese male. This was followed by the verification of epithelium-specific characteristics, such as ultrastructure and biomarkers. A distinct SP subpopulation (4.45±1.07% was isolated by Hoechst 33342 efflux analysis from cultured LSCCs by using a flow cytometer. Cancer stem cell (CSC-associated assays, including expression of self-renewal and CSC marker genes, proliferation, differentiation, spheroid formation, chemotherapy resistance, and tumorigenicity were then conducted between SP and non-SP (NSP LSCCs. In vitro and in vivo assays revealed that SP cells manifested preferential expression of self-renewal and CSC marker genes, higher capacity for proliferation, differentiation, and spheroid formation; enhanced resistance to chemotherapy; and greater xenograft tumorigenicity in immunodeficient mice compared with NSP cells. These findings suggest that the primary cultured and purified LSCCs contain cancer stem-like SP cells, which may serve as a valuable model for CSC research in LSCC.

  4. Molecular characterisation of stromal populations derived from human embryonic stem cells

    DEFF Research Database (Denmark)

    Harkness, L.; Twine, N. A.; Abu Dawud, R.

    2015-01-01

    Human bone marrow-derived stromal (skeletal) stem cells (BM-hMSC) are being employed in an increasing number of clinical trials for tissue regeneration. A limiting factor for their clinical use is the inability to obtain sufficient cell numbers. Human embryonic stem cells (hESC) can provide an un...

  5. Stem cell self-renewal in intestinal crypt

    NARCIS (Netherlands)

    Simons, B.D.; Clevers, H.

    2011-01-01

    As a rapidly cycling tissue capable of fast repair and regeneration, the intestinal epithelium has emerged as a favored model system to explore the principles of adult stem cell biology. However, until recently, the identity and characteristics of the stem cell population in both the small intestine

  6. Discovery of a stem-like multipotent cell fate.

    Science.gov (United States)

    Paffhausen, Emily S; Alowais, Yasir; Chao, Cara W; Callihan, Evan C; Creswell, Karen; Bracht, John R

    2018-01-01

    Adipose derived stem cells (ASCs) can be obtained from lipoaspirates and induced in vitro to differentiate into bone, cartilage, and fat. Using this powerful model system we show that after in vitro adipose differentiation a population of cells retain stem-like qualities including multipotency. They are lipid (-), retain the ability to propagate, express two known stem cell markers, and maintain the capacity for trilineage differentiation into chondrocytes, adipocytes, and osteoblasts. However, these cells are not traditional stem cells because gene expression analysis showed an overall expression profile similar to that of adipocytes. In addition to broadening our understanding of cellular multipotency, our work may be particularly relevant to obesity-associated metabolic disorders. The adipose expandability hypothesis proposes that inability to differentiate new adipocytes is a primary cause of metabolic syndrome in obesity, including diabetes and cardiovascular disease. Here we have defined a differentiation-resistant stem-like multipotent cell population that may be involved in regulation of adipose expandability in vivo and may therefore play key roles in the comorbidities of obesity.

  7. Stem cell applications in military medicine.

    Science.gov (United States)

    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.

  8. Mesenchymal to Epithelial Transition Mediated by CDH1 Promotes Spontaneous Reprogramming of Male Germline Stem Cells to Pluripotency

    Directory of Open Access Journals (Sweden)

    Junhui An

    2017-02-01

    Full Text Available Cultured spermatogonial stem cells (GSCs can spontaneously form pluripotent cells in certain culture conditions. However, GSC reprogramming is a rare event that is largely unexplained. We show GSCs have high expression of mesenchymal to epithelial transition (MET suppressors resulting in a developmental barrier inhibiting GSC reprogramming. Either increasing OCT4 or repressing transforming growth factor β (TGF-β signaling promotes GSC reprogramming by upregulating CDH1 and boosting MET. Reducing ZEB1 also enhances GSC reprogramming through its direct effect on CDH1. RNA sequencing shows that rare GSCs, identified as CDH1+ after trypsin digestion, are epithelial-like cells. CDH1+ GSCs exhibit enhanced reprogramming and become more prevalent during the course of reprogramming. Our results provide a mechanistic explanation for the spontaneous emergence of pluripotent cells from GSC cultures; namely, rare GSCs upregulate CDH1 and initiate MET, processes normally kept in check by ZEB1 and TGF-β signaling, thereby ensuring germ cells are protected from aberrant acquisition of pluripotency.

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

    Science.gov (United States)

    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.

  10. Stem Cell-Based Therapies for Polyglutamine Diseases.

    Science.gov (United States)

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

    2018-01-01

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

  11. Biophysical regulation of stem cell differentiation.

    Science.gov (United States)

    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.

  12. Transcriptional profiling of putative human epithelial stem cells

    Directory of Open Access Journals (Sweden)

    Koçer Salih S

    2008-07-01

    Full Text Available Abstract Background Human interfollicular epidermis is sustained by the proliferation of stem cells and their progeny, transient amplifying cells. Molecular characterization of these two cell populations is essential for better understanding of self renewal, differentiation and mechanisms of skin pathogenesis. The purpose of this study was to obtain gene expression profiles of alpha 6+/MHCI+, transient amplifying cells and alpha 6+/MHCI-, putative stem cells, and to compare them with existing data bases of gene expression profiles of hair follicle stem cells. The expression of Major Histocompatibility Complex (MHC class I, previously shown to be absent in stem cells in several tissues, and alpha 6 integrin were used to isolate MHCI positive basal cells, and MHCI low/negative basal cells. Results Transcriptional profiles of the two cell populations were determined and comparisons made with published data for hair follicle stem cell gene expression profiles. We demonstrate that presumptive interfollicular stem cells, alpha 6+/MHCI- cells, are enriched in messenger RNAs encoding surface receptors, cell adhesion molecules, extracellular matrix proteins, transcripts encoding members of IFN-alpha family proteins and components of IFN signaling, but contain lower levels of transcripts encoding proteins which take part in energy metabolism, cell cycle, ribosome biosynthesis, splicing, protein translation, degradation, DNA replication, repair, and chromosome remodeling. Furthermore, our data indicate that the cell signaling pathways Notch1 and NF-κB are downregulated/inhibited in MHC negative basal cells. Conclusion This study demonstrates that alpha 6+/MHCI- cells have additional characteristics attributed to stem cells. Moreover, the transcription profile of alpha 6+/MHCI- cells shows similarities to transcription profiles of mouse hair follicle bulge cells known to be enriched for stem cells. Collectively, our data suggests that alpha 6+/MHCI- cells

  13. Advanced research on separating prostate cancer stem cells

    International Nuclear Information System (INIS)

    Hao Yumei; He Xin; Song Naling

    2013-01-01

    Prostate cancer is a common malignant tumor in male urinary system,and may easily develop into the hormone refractory prostate cancer which can hardly be cured. Recent studies had found that the prostate cancer stem cells may be the source of the prostate cancer's occurrence,development, metastasis and recurrence. The therapy targeting the prostate cancer stem cells may be the effective way to cure prostate cancer. But these cells is too low to be detected. The difficulty lies in the low separation efficiency of prostate cancer stem cell, so the effectively separating prostate cancer stem cells occupied the main position for the more in-depth research of prostate cancer stem cells. This paper reviews the research progress and existing problems on the several main separating methods of prostate cancer stem cells, includes the fluorescence activated cells sorting and magnetic activated cells sorting based on prostate cancer stem cell surface markers, the side-population sorting and serum-free medium sphere forming sorting based on prostate cancer stem cell's biology. (authors)

  14. Stem cell factor enhances the survival of murine intestinal stem cells after photon irradiation

    International Nuclear Information System (INIS)

    Leigh, B.R.; Khan, W.; Hancock, S.L.

    1995-01-01

    Recombinant rat stem cell factor (SCF) has been shown to decrease lethality in mice exposed to total-body irradiation (TBI) in the lower range of lethality through radioprotection of hematopoietic stem cells and acceleration of bone marrow repopulation. This study evaluates the effect of SCF on the survival of the intestinal mucosal stem cell after TBI. This non-hematopoietic cell is clinically relevant. Gastrointestinal toxicity is common during and after abdominal and pelvic radiation therapy and limits the radiation dose in these regions. As observed with bone marrow, the administration of SCF to mice prior to TBI enhanced the survival of mouse duodenal crypt stem cells. The maximum enhancement of survival was seen when 100 μ/kg of SCF was given intraperitoneally 8 h before irradiation. This regimen increased the survival of duodenal crypt stem cells after 12.0 Gy TBI from 22.5 ± 0.7 per duodenal cross section for controls to 30.0 ± 1.7 after treatment with SCF (P=0.03). The TBI dose producing 50% mortality of 6 days (LD 50/6 ) was increased from 14.9 Gy for control mice to 19.0 Gy for mice treated with SCF (dose modification factor = 1.28). These findings demonstrate that SCF (dose modification factor = 1.28). These findings demonstrate that SCF has radioprotective effects on a non-hematopoietic stem cell population and suggest that SCF may be of clinical value in preventing radiation injury to the intestine. 29 refs., 4 figs

  15. Gastric stem cells and gastric cancer stem cells

    OpenAIRE

    Han, Myoung-Eun; Oh, Sae-Ock

    2013-01-01

    The gastric epithelium is continuously regenerated by gastric stem cells, which give rise to various kinds of daughter cells, including parietal cells, chief cells, surface mucous cells, mucous neck cells, and enteroendocrine cells. The self-renewal and differentiation of gastric stem cells need delicate regulation to maintain the normal physiology of the stomach. Recently, it was hypothesized that cancer stem cells drive the cancer growth and metastasis. In contrast to conventional clonal ev...

  16. Mesenchymal Stem Cells in Tissue Growth and Repair

    OpenAIRE

    Kalinina, N.I.; Sysoeva, V.Yu.; Rubina, K.A.; Parfenova, Ye.V.; Tkachuk, V.A.

    2011-01-01

    It has been established in the recent several decades that stem cells play a crucial role in tissue renewal and regeneration. Mesenchymal stem cells (MSCs) are part of the most important population of adult stem cells. These cells have hereby been identified for the very first time and subsequently isolated from bone marrow stroma. Bone marrow-derived MSCs have been believed to play the role of a source of cells for the renewal and repair of connective tissues, including bone, cartilage and a...

  17. Cancer Stem Cells – New Approach to Cancerogenensis and Treatment

    Directory of Open Access Journals (Sweden)

    Zuzana Mačingová

    2008-01-01

    Full Text Available Recently, there is an increasing evidence supporting the theory of cancer stem cells not only in leukemia but also in solid cancer. To date, the existence of cancer stem cells has been proven in acute and chronic myeloid leukemia, in breast cancer, in brain tumors, in lung cancer and gastrointestinal tumors. This review is focusing on the recent discovery of stem cells in leukemia, human brain tumors and breast cancer. A small population of cells in the tumor (less than 1 % shows the potential to give rise to the tumor and its growth. These cells have a substantial characteristic of stem cells – ability for self-renewal without loss of proliferation capacity with each cell division. Furthermore they are immortal, rather resistant to treatment and express typical markers of stem cells. The origin of these resident cancer stem cells is not clear. Whether the cancer stem cells originate from normal stem cells in consequence of genetic and epigenetic changes and/or redifferentiation from somatic tumor cells to the stem-like cells remains to be investigated. We propose the idea of the relation between normal tissue stem cells and cancer stem cells and their populations – progenitor cells. Based on this we highlight one of the major characteristic of stem cell – plasticity, which is equally important in the physiological regeneration process as well as carcinogenesis. Furthermore, we consider the microenvironment as a limiting factor for tumor genesis in AML, breast cancer and brain tumors. Thus the biological properties of cancer stem cells are just beginning to be revealed, the continuation of these studies should lead to the development of cancer stem cells target therapies for cancer treatment.

  18.  Hair follicle as a novel source of stem cells

    Directory of Open Access Journals (Sweden)

    Romana Joachimiak

    2012-04-01

    Full Text Available  Tissue engineering as a rapidly developing branch of science offers hope for the use of its products in medical practice. Among the components of tissue substitutes are different types of cells, especially stem cells. A promising source of adult stem cells is hair follicles. Development of follicles in the skin takes place even during fetal life. They arise due to the impact of epidermal and mesenchymal cells. The next steps in the formation of hair follicles are under the control of many factors. Hair follicles are the niche of various stem cell populations and are a major source of cells responsible for regeneration of the hair, sebaceous glands and epidermis. The term „hair follicle stem cells” is most often used in relation to the epithelial cell population. Hair follicle stem cell studies are complicated by the fact that these stem cells divide relatively rarely.The aim of this study is to present the characteristics of cells isolated from the hair follicle in the light of recent research.

  19. Subsequent vitiligo after hematopoietic stem cell transplantation: A nationwide population-based cohort study from Korea.

    Science.gov (United States)

    Bae, Jung Min; Choi, Kwang Hyun; Jung, Han Mi; Kim, Sook Young; Kim, Miri; Kim, Gyung Moon; Yu, Dong Soo; Lee, Young Bok

    2017-03-01

    Subsequent vitiligo after hematopoietic stem cell transplantation (HSCT) has been described sporadically in case series. To investigate the incidence and risk factors of subsequent vitiligo after HSCT. A nationwide, population-based cohort study was performed using the Korean National Health Insurance Claims Database from 2009 to 2013. All HSCT recipients who had undergone HSCT between 2010 and 2011 and not treatment for vitiligo in 2009 (to exclude preexisting active vitiligo) were included in the HSCT recipient group, and an age- and sex-matched control group without HSCT was also established. A total of 2747 HSCT recipients and 8241 controls were enrolled. Newly acquired vitiligo occurred in 1.06% of HSCT recipients between 2010 and 2013, and there was a significant increase (OR 3.130, 95% CI 1.859-5.271) in cases of vitiligo in HSCT recipients compared with controls (0.34%). Allogeneic HSCT (OR 5.593, 95% CI 1.628-19.213) and bone marrow-sourced stem cells (as compared with peripheral blood-sourced stem cells; OR 2.492, 95% CI 1.114-5.576) were independently associated with the development of vitiligo after HSCT. Medical record review was not available. Vitiligo developed at a significantly increased rate after HSCT compared with controls. Allogeneic HSCT and bone marrow-sourced stem cells were independent risk factors. Copyright © 2016 American Academy of Dermatology, Inc. Published by Elsevier Inc. All rights reserved.

  20. NSC30049 inhibits Chk1 pathway in 5-FU-resistant CRC bulk and stem cell populations.

    Science.gov (United States)

    Narayan, Satya; Jaiswal, Aruna S; Sharma, Ritika; Nawab, Akbar; Duckworth, Lizette Vila; Law, Brian K; Zajac-Kaye, Maria; George, Thomas J; Sharma, Jay; Sharma, Arun K; Hromas, Robert A

    2017-08-22

    The 5-fluorouracil (5-FU) treatment induces DNA damage and stalling of DNA replication forks. These stalled replication forks then collapse to form one sided double-strand breaks, leading to apoptosis. However, colorectal cancer (CRC) stem cells rapidly repair the stalled/collapsed replication forks and overcome treatment effects. Recent evidence suggests a critical role of checkpoint kinase 1 (Chk1) in preventing the replicative stress. Therefore, Chk1 kinase has been a target for developing mono or combination therapeutic agents. In the present study, we have identified a novel orphan molecule NSC30049 (NSC49L) that is effective alone, and in combination potentiates 5-FU-mediated growth inhibition of CRC heterogeneous bulk and FOLFOX-resistant cell lines in culture with minimal effect on normal colonic epithelial cells. It also inhibits the sphere forming activity of CRC stem cells, and decreases the expression levels of mRNAs of CRC stem cell marker genes. Results showed that NSC49L induces 5-FU-mediated S-phase cell cycle arrest due to increased load of DNA damage and increased γ-H2AX staining as a mechanism of cytotoxicity. The pharmacokinetic analysis showed a higher bioavailability of this compound, however, with a short plasma half-life. The drug is highly tolerated by animals with no pathological aberrations. Furthermore, NSC49L showed very potent activity in a HDTX model of CRC stem cell tumors either alone or in combination with 5-FU. Thus, NSC49L as a single agent or combined with 5-FU can be developed as a therapeutic agent by targeting the Chk1 pathway in 5-FU-resistant CRC heterogeneous bulk and CRC stem cell populations.

  1. CD44 staining of cancer stem-like cells is influenced by down-regulation of CD44 variant isoforms and up-regulation of the standard CD44 isoform in the population of cells that have undergone epithelial-to-mesenchymal transition.

    Directory of Open Access Journals (Sweden)

    Adrian Biddle

    Full Text Available CD44 is commonly used as a cell surface marker of cancer stem-like cells in epithelial tumours, and we have previously demonstrated the existence of two different CD44(high cancer stem-like cell populations in squamous cell carcinoma, one having undergone epithelial-to-mesenchymal transition and the other maintaining an epithelial phenotype. Alternative splicing of CD44 variant exons generates a great many isoforms, and it is not known which isoforms are expressed on the surface of the two different cancer stem-like cell phenotypes. Here, we demonstrate that cancer stem-like cells with an epithelial phenotype predominantly express isoforms containing the variant exons, whereas the cancer stem-like cells that have undergone an epithelial-to-mesenchymal transition down-regulate these variant isoforms and up-regulate expression of the standard CD44 isoform that contains no variant exons. In addition, we find that enzymatic treatments used to dissociate cells from tissue culture or fresh tumour specimens cause destruction of variant CD44 isoforms at the cell surface whereas expression of the standard CD44 isoform is preserved. This results in enrichment within the CD44(high population of cancer stem-like cells that have undergone an epithelial-to-mesenchymal transition and depletion from the CD44(high population of cancer stem-like cells that maintain an epithelial phenotype, and therefore greatly effects the characteristics of any cancer stem-like cell population isolated based on expression of CD44. As well as effecting the CD44(high population, enzymatic treatment also reduces the percentage of the total epithelial cancer cell population staining CD44-positive, with potential implications for studies that aim to use CD44-positive staining as a prognostic indicator. Analyses of the properties of cancer stem-like cells are largely dependent on the ability to accurately identify and assay these populations. It is therefore critical that

  2. Human skeletal muscle-derived stem cells retain stem cell properties after expansion in myosphere culture

    International Nuclear Information System (INIS)

    Wei, Yan; Li, Yuan; Chen, Chao; Stoelzel, Katharina; Kaufmann, Andreas M.; Albers, Andreas E.

    2011-01-01

    Human skeletal muscle contains an accessible adult stem-cell compartment in which differentiated myofibers are maintained and replaced by a self-renewing stem cell pool. Previously, studies using mouse models have established a critical role for resident stem cells in skeletal muscle, but little is known about this paradigm in human muscle. Here, we report the reproducible isolation of a population of cells from human skeletal muscle that is able to proliferate for extended periods of time as floating clusters of rounded cells, termed 'myospheres' or myosphere-derived progenitor cells (MDPCs). The phenotypic characteristics and functional properties of these cells were determined using reverse transcription-polymerase chain reaction (RT-PCR), flow cytometry and immunocytochemistry. Our results showed that these cells are clonogenic, express skeletal progenitor cell markers Pax7, ALDH1, Myod, and Desmin and the stem cell markers Nanog, Sox2, and Oct3/4 significantly elevated over controls. They could be maintained proliferatively active in vitro for more than 20 weeks and passaged at least 18 times, despite an average donor-age of 63 years. Individual clones (4.2%) derived from single cells were successfully expanded showing clonogenic potential and sustained proliferation of a subpopulation in the myospheres. Myosphere-derived cells were capable of spontaneous differentiation into myotubes in differentiation media and into other mesodermal cell lineages in induction media. We demonstrate here that direct culture and expansion of stem cells from human skeletal muscle is straightforward and reproducible with the appropriate technique. These cells may provide a viable resource of adult stem cells for future therapies of disease affecting skeletal muscle or mesenchymal lineage derived cell types.

  3. An in vivo requirement for the mediator subunit med14 in the maintenance of stem cell populations.

    Science.gov (United States)

    Burrows, Jeffrey T A; Pearson, Bret J; Scott, Ian C

    2015-04-14

    The Mediator complex has recently been shown to be a key player in the maintenance of embryonic and induced pluripotent stem cells. However, the in vivo consequences of loss of many Mediator subunits are unknown. We identified med14 as the gene affected in the zebrafish logelei (log) mutant, which displayed a morphological arrest by 2 days of development. Surprisingly, microarray analysis showed that transcription was not broadly affected in log mutants. Indeed, log cells transplanted into a wild-type environment were able to survive into adulthood. In planarians, RNAi knockdown demonstrated a requirement for med14 and many other Mediator components in adult stem cell maintenance and regeneration. Multiple stem/progenitor cell populations were observed to be reduced or absent in zebrafish med14 mutant embryos. Taken together, our results show a critical, evolutionarily conserved, in vivo function for Med14 (and Mediator) in stem cell maintenance, distinct from a general role in transcription. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

  4. Overcoming Multidrug Resistance in Cancer Stem Cells

    Directory of Open Access Journals (Sweden)

    Karobi Moitra

    2015-01-01

    Full Text Available 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.

  5. Epigenetic modulation of dental pulp stem cells: implications for regenerative endodontics.

    Science.gov (United States)

    Duncan, H F; Smith, A J; Fleming, G J P; Cooper, P R

    2016-05-01

    Dental pulp stem cells (DPSCs) offer significant potential for use in regenerative endodontics, and therefore, identifying cellular regulators that control stem cell fate is critical to devising novel treatment strategies. Stem cell lineage commitment and differentiation are regulated by an intricate range of host and environmental factors of which epigenetic influence is considered vital. Epigenetic modification of DNA and DNA-associated histone proteins has been demonstrated to control cell phenotype and regulate the renewal and pluripotency of stem cell populations. The activities of the nuclear enzymes, histone deacetylases, are increasingly being recognized as potential targets for pharmacologically inducing stem cell differentiation and dedifferentiation. Depending on cell maturity and niche in vitro, low concentration histone deacetylase inhibitor (HDACi) application can promote dedifferentiation of several post-natal and mouse embryonic stem cell populations and conversely increase differentiation and accelerate mineralization in DPSC populations, whilst animal studies have shown an HDACi-induced increase in stem cell marker expression during organ regeneration. Notably, both HDAC and DNA methyltransferase inhibitors have also been demonstrated to dramatically increase the reprogramming of somatic cells to induced pluripotent stem cells (iPSCs) for use in regenerative therapeutic procedures. As the regulation of cell fate will likely remain the subject of intense future research activity, this review aims to describe the current knowledge relating to stem cell epigenetic modification, focusing on the role of HDACi on alteration of DPSC phenotype, whilst presenting the potential for therapeutic application as part of regenerative endodontic regimens. © 2015 International Endodontic Journal. Published by John Wiley & Sons Ltd.

  6. "NeuroStem Chip": a novel highly specialized tool to study neural differentiation pathways in human stem cells

    Directory of Open Access Journals (Sweden)

    Li Jia-Yi

    2007-02-01

    Full Text Available Abstract Background Human stem cells are viewed as a possible source of neurons for a cell-based therapy of neurodegenerative disorders, such as Parkinson's disease. Several protocols that generate different types of neurons from human stem cells (hSCs have been developed. Nevertheless, the cellular mechanisms that underlie the development of neurons in vitro as they are subjected to the specific differentiation protocols are often poorly understood. Results We have designed a focused DNA (oligonucleotide-based large-scale microarray platform (named "NeuroStem Chip" and used it to study gene expression patterns in hSCs as they differentiate into neurons. We have selected genes that are relevant to cells (i being stem cells, (ii becoming neurons, and (iii being neurons. The NeuroStem Chip has over 1,300 pre-selected gene targets and multiple controls spotted in quadruplicates (~46,000 spots total. In this study, we present the NeuroStem Chip in detail and describe the special advantages it offers to the fields of experimental neurology and stem cell biology. To illustrate the utility of NeuroStem Chip platform, we have characterized an undifferentiated population of pluripotent human embryonic stem cells (hESCs, cell line SA02. In addition, we have performed a comparative gene expression analysis of those cells versus a heterogeneous population of hESC-derived cells committed towards neuronal/dopaminergic differentiation pathway by co-culturing with PA6 stromal cells for 16 days and containing a few tyrosine hydroxylase-positive dopaminergic neurons. Conclusion We characterized the gene expression profiles of undifferentiated and dopaminergic lineage-committed hESC-derived cells using a highly focused custom microarray platform (NeuroStem Chip that can become an important research tool in human stem cell biology. We propose that the areas of application for NeuroStem microarray platform could be the following: (i characterization of the

  7. TRAPping telomerase within the intestinal stem cell niche

    OpenAIRE

    Pech, Matthew F; Artandi, Steven E

    2011-01-01

    Recent work from Hans Clevers' lab reveals high telomerase activity and telomere length in dividing LGR5-positive intestinal stem cells. They further report random chromosome segregation and thus challenge the ‘immortal strand' hypothesis at least for this stem cell population.

  8. Sorting live stem cells based on Sox2 mRNA expression.

    Directory of Open Access Journals (Sweden)

    Hans M Larsson

    Full Text Available While cell sorting usually relies on cell-surface protein markers, molecular beacons (MBs offer the potential to sort cells based on the presence of any expressed mRNA and in principle could be extremely useful to sort rare cell populations from primary isolates. We show here how stem cells can be purified from mixed cell populations by sorting based on MBs. Specifically, we designed molecular beacons targeting Sox2, a well-known stem cell marker for murine embryonic (mES and neural stem cells (NSC. One of our designed molecular beacons displayed an increase in fluorescence compared to a nonspecific molecular beacon both in vitro and in vivo when tested in mES and NSCs. We sorted Sox2-MB(+SSEA1(+ cells from a mixed population of 4-day retinoic acid-treated mES cells and effectively isolated live undifferentiated stem cells. Additionally, Sox2-MB(+ cells isolated from primary mouse brains were sorted and generated neurospheres with higher efficiency than Sox2-MB(- cells. These results demonstrate the utility of MBs for stem cell sorting in an mRNA-specific manner.

  9. Extinction models for cancer stem cell therapy

    Science.gov (United States)

    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

  10. Generation of Human Induced Pluripotent Stem Cells Using RNA-Based Sendai Virus System and Pluripotency Validation of the Resulting Cell Population.

    Science.gov (United States)

    Chichagova, Valeria; Sanchez-Vera, Irene; Armstrong, Lyle; Steel, David; Lako, Majlinda

    2016-01-01

    Human induced pluripotent stem cells (hiPSCs) provide a platform for studying human disease in vitro, increase our understanding of human embryonic development, and provide clinically relevant cell types for transplantation, drug testing, and toxicology studies. Since their discovery, numerous advances have been made in order to eliminate issues such as vector integration into the host genome, low reprogramming efficiency, incomplete reprogramming and acquisition of genomic instabilities. One of the ways to achieve integration-free reprogramming is by using RNA-based Sendai virus. Here we describe a method to generate hiPSCs with Sendai virus in both feeder-free and feeder-dependent culture systems. Additionally, we illustrate methods by which to validate pluripotency of the resulting stem cell population.

  11. Restoration of spermatogenesis and male fertility by transplantation of dispersed testicular cells in the chicken

    Czech Academy of Sciences Publication Activity Database

    Trefil, P.; Micaková, A.; Mucksová, J.; Hejnar, Jiří; Poplštein, M.; Bakst, M. R.; Kalina, J.; Brillard, J.-P.

    2006-01-01

    Roč. 75, č. 4 (2006), s. 575-581 ISSN 0006-3363 R&D Projects: GA ČR(CZ) GA523/04/0569 Institutional research plan: CEZ:AV0Z50520514 Keywords : transplantation of germ cells in chicken * spermatogonial stem cells * chicken transgenesis Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.498, year: 2006

  12. Derivation of Pluripotent Cells from Mouse SSCs Seems to Be Age Dependent

    Directory of Open Access Journals (Sweden)

    Hossein Azizi

    2016-01-01

    Full Text Available Here, we aimed to answer important and fundamental questions in germ cell biology with special focus on the age of the male donor cells and the possibility to generate embryonic stem cell- (ESC- like cells. While it is believed that spermatogonial stem cells (SSCs and truly pluripotent ESC-like cells can be isolated from adult mice, it remained unknown if the spontaneous conversion of SSCs to ESC-like cells fails at some age. Similarly, there have been differences in the literature about the duration of cultures during which ESC-like cells may appear. We demonstrate the possibility to derive ESC-like cells from SSC cultures until they reach adolescence or up to 7 weeks of age, but we point out the impossibility to derive these cells from older, mature adult mice. The inability of real adult SSCs to shift to a pluripotent state coincides with a decline in expression of the core pluripotency genes Oct4, Nanog, and Sox2 in SSCs with age. At the same time genes of the spermatogonial differentiation pathway increase. The generated ESC-like cells were similar to ESCs and express pluripotency markers. In vitro they differentiate into all three germ lineages; they form complex teratomas after transplantation in SCID mice and produce chimeric mice.

  13. Premeiotic germ cell defect in seminiferous tubules of Atm-null testis

    International Nuclear Information System (INIS)

    Takubo, Keiyo; Hirao, Atsushi; Ohmura, Masako; Azuma, Masaki; Arai, Fumio; Nagamatsu, Go; Suda, Toshio

    2006-01-01

    Lifelong spermatogenesis is maintained by coordinated sequential processes including self-renewal of stem cells, proliferation of spermatogonial cells, meiotic division, and spermiogenesis. It has been shown that ataxia telangiectasia-mutated (ATM) is required for meiotic division of the seminiferous tubules. Here, we show that, in addition to its role in meiosis, ATM has a pivotal role in premeiotic germ cell maintenance. ATM is activated in premeiotic spermatogonial cells and the Atm-null testis shows progressive degeneration. In Atm-null testicular cells, differing from bone marrow cells of Atm-null mice, reactive oxygen species-mediated p16 Ink4a activation does not occur in Atm-null premeiotic germ cells, which suggests the involvement of different signaling pathways from bone marrow defects. Although Atm-null bone marrow undergoes p16 Ink4a -mediated cellular senescence program, Atm-null premeiotic germ cells exhibited cell cycle arrest and apoptotic elimination of premeiotic germ cells, which is different from p16 Ink4a -mediated senescence

  14. Self-renewal molecular mechanisms of colorectal cancer stem cells

    OpenAIRE

    Pan, Tianhui; Xu, Jinghong; Zhu, Yongliang

    2016-01-01

    Colorectal cancer stem cells (CCSCs) represent a small fraction of the colorectal cancer cell population that possess self-renewal and multi-lineage differentiation potential and drive tumorigenicity. Self-renewal is essential for the malignant biological behaviors of colorectal cancer stem cells. While the self-renewal molecular mechanisms of colorectal cancer stem cells are not yet fully understood, the aberrant activation of signaling pathways, such as Wnt, Notch, transforming growth facto...

  15. Epidermal stem cells: location, potential and contribution to cancer.

    Science.gov (United States)

    Ambler, C A; Määttä, A

    2009-01-01

    Epidermal stem cells have been classically characterized as slow-cycling, long-lived cells that reside in discrete niches in the skin. Gene expression studies of niche-resident cells have revealed a number of stem cell markers and regulators, including the Wnt/beta-catenin, Notch, p63, c-Myc and Hedgehog pathways. A new study challenges the traditional developmental paradigm of slow-cycling stem cells and rapid-cycling transit amplifying cells in some epidermal regions, and there is mounting evidence to suggest that multi-lineage epidermal progenitors can be isolated from highly proliferative, non-niche regions. Whether there is a unique microenvironment surrounding these progenitors remains to be determined. Interestingly, cancer stem cells derived from epidermal tumours exist independent of the classic skin stem cell niche, yet also have stem cell properties, including multi-lineage differentiation. This review summarizes recent studies identifying the location and regulators of mouse and human epidermal stem cells and highlights the strategies used to identify cancer stem cells, including expression of normal epidermal stem cell markers, expression of cancer stem cell markers identified in other epidermal tumours and characterization of side-population tumour cells.

  16. Types of Stem Cells

    Science.gov (United States)

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

  17. Satellite Cells and the Muscle Stem Cell Niche

    Science.gov (United States)

    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

  18. Stem cells

    NARCIS (Netherlands)

    Jukes, Jojanneke; Both, Sanne; Post, Janine; van Blitterswijk, Clemens; Karperien, Marcel; de Boer, Jan; van Blitterswijk, Clemens A.

    2008-01-01

    This chapter defines stem cells and their properties. It identifies the major differences between embryonic and adult stem cells. Stem cells can be defined by two properties: the ability to make identical copies of themselves and the ability to form other cell types of the body. These properties are

  19. Mesenchymal stem cell-mediated functional tooth regeneration in swine.

    Directory of Open Access Journals (Sweden)

    Wataru Sonoyama

    2006-12-01

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

  20. In vitro cytotoxicity of nanoparticles in mammalian germline stem cells.

    Science.gov (United States)

    Braydich-Stolle, Laura; Hussain, Saber; Schlager, John J; Hofmann, Marie-Claude

    2005-12-01

    Gametogenesis is a complex biological process that is particularly sensitive to environmental insults such as chemicals. Many chemicals have a negative impact on the germline, either by directly affecting the germ cells, or indirectly through their action on the somatic nursing cells. Ultimately, these effects can inhibit fertility, and they may have negative consequences for the development of the offspring. Recently, nanomaterials such as nanotubes, nanowires, fullerene derivatives (buckyballs), and quantum dots have received enormous national attention in the creation of new types of analytical tools for biotechnology and the life sciences. Despite the wide application of nanomaterials, there is a serious lack of information concerning their impact on human health and the environment. Thus, there are limited studies available on toxicity of nanoparticles for risk assessment of nanomaterials. The purpose of this study was to assess the suitability of a mouse spermatogonial stem cell line as a model to assess nanotoxicity in the male germline in vitro. The effects of different types of nanoparticles on these cells were evaluated by light microscopy, and by cell proliferation and standard cytotoxicity assays. Our results demonstrate a concentration-dependent toxicity for all types of particles tested, whereas the corresponding soluble salts had no significant effect. Silver nanoparticles were the most toxic while molybdenum trioxide (MoO(3)) nanoparticles were the least toxic. Our results suggest that this cell line provides a valuable model with which to assess the cytotoxicity of nanoparticles in the germ line in vitro.

  1. CD146 Expression Influences Periapical Cyst Mesenchymal Stem Cell Properties.

    Science.gov (United States)

    Paduano, Francesco; Marrelli, Massimo; Palmieri, Francesca; Tatullo, Marco

    2016-10-01

    Recent studies have identified a new human dental derived progenitor cell population with multi-lineage differentiation potential referred to as human periapical cyst mesenchymal stem cells (hPCy-MSCs). In the present study, we compared two subpopulations of hPCy-MSCs characterised by the low or high expression of CD146 to establish whether this expression can regulate their stem cell properties. Using flow cytometry, we evaluated the stem cell marker profile of hPCy-MSCs during passaging. Furthermore, CD146 Low and CD146 High cells were sorted by magnetic beads and subsequently both cell populations were evaluated for differences in their proliferation, self-renewal, stem cell surface markers, stemness genes expression and osteogenic differentiation potential.We found that hPCy-MSCs possessed a stable expression of several mesenchymal stem cell surface markers, whereas CD146 expression declined during passaging.In addition, sorted CD146 Low cells proliferated significantly faster, displayed higher colony-forming unit-fibroblast capacity and showed higher expression of Klf4 when compared to the CD146 High subset. Significantly, the osteogenic potential of hPCy-MSCs was greater in the CD146 Low than in CD146 High population. These results demonstrate that CD146 is spontaneously downregulated with passaging at both mRNA and protein levels and that the high expression of CD146 reduces the proliferative, self-renewal and osteogenic differentiation potential of hPCy-MSCs. In conclusion, our study demonstrates that changes in the expression of CD146 can influence the stem cell properties of hPCy-MSCs.

  2. Defining a stem cell hierarchy in the intestine: markers, caveats and controversies

    Science.gov (United States)

    Smith, Nicholas R.; Gallagher, Alexandra C.

    2016-01-01

    Abstract The past decade has appreciated rapid advance in identifying the once elusive intestinal stem cell (ISC) populations that fuel the continual renewal of the epithelial layer. This advance was largely driven by identification of novel stem cell marker genes, revealing the existence of quiescent, slowly‐ and active‐cycling ISC populations. However, a critical barrier for translating this knowledge to human health and disease remains elucidating the functional interplay between diverse stem cell populations. Currently, the precise hierarchical and regulatory relationships between these ISC populations are under intense scrutiny. The classical theory of a linear hierarchy, where quiescent and slowly‐cycling stem cells self‐renew but replenish an active‐cycling population, is well established in other rapidly renewing tissues such as the haematopoietic system. Efforts to definitively establish a similar stem cell hierarchy within the intestinal epithelium have yielded conflicting results, been difficult to interpret, and suggest non‐conventional alternatives to a linear hierarchy. While these new and potentially paradigm‐shifting discoveries are intriguing, the field will require development of a number of critical tools, including highly specific stem cell marker genes along with more rigorous experimental methodologies, to delineate the complex cellular relationships within this dynamic organ system. PMID:26864260

  3. Stem cell biobanks.

    Science.gov (United States)

    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.

  4. Stem Cell Basics

    Science.gov (United States)

    ... Tips Info Center Research Topics Federal Policy Glossary Stem Cell Information General Information Clinical Trials Funding Information Current ... Basics » Stem Cell Basics I. Back to top Stem Cell Basics I. Introduction: What are stem cells, and ...

  5. Mesenchymal stem cells induce mature dendritic cells into a novel Jagged-2-dependent regulatory dendritic cell population.

    Science.gov (United States)

    Zhang, Bin; Liu, Rui; Shi, Dan; Liu, Xingxia; Chen, Yuan; Dou, Xiaowei; Zhu, Xishan; Lu, Chunhua; Liang, Wei; Liao, Lianming; Zenke, Martin; Zhao, Robert C H

    2009-01-01

    Mesenchymal stem cells (MSCs), in addition to their multilineage differentiation, exert immunomodulatory effects on immune cells, even dendritic cells (DCs). However, whether they influence the destiny of full mature DCs (maDCs) remains controversial. Here we report that MSCs vigorously promote proliferation of maDCs, significantly reduce their expression of Ia, CD11c, CD80, CD86, and CD40 while increasing CD11b expression. Interestingly, though these phenotypes clearly suggest their skew to immature status, bacterial lipopolysaccharide (LPS) stimulation could not reverse this trend. Moreover, high endocytosic capacity, low immunogenicity, and strong immunoregulatory function of MSC-treated maDCs (MSC-DCs) were also observed. Furthermore we found that MSCs, partly via cell-cell contact, drive maDCs to differentiate into a novel Jagged-2-dependent regulatory DC population and escape their apoptotic fate. These results further support the role of MSCs in preventing rejection in organ transplantation and treatment of autoimmune disease.

  6. Colorectal adenoma stem-like cell populations: associations with adenoma characteristics and metachronous colorectal neoplasia.

    Science.gov (United States)

    Bartley, Angela N; Parikh, Nila; Hsu, Chiu-Hsieh; Roe, Denise J; Buckmeier, Julie A; Corley, Lynda; Phipps, Ron A; Gallick, Gary; Lance, Peter; Thompson, Patricia A; Hamilton, Stanley R

    2013-11-01

    Cancer stem cells have tumor-initiation and tumor-maintenance capabilities. Stem-like cells are present in colorectal adenomas, but their relationship to adenoma pathology and patient characteristics, including metachronous development of an additional adenoma ("recurrence"), has not been studied extensively. We evaluated the expression of aldehyde dehydrogenase isoform 1A1 (ALDH1A1), a putative stem cell marker, in baseline adenomas from the placebo arm of chemoprevention trial participants with colonoscopic follow-up. An exploratory set of 20 baseline adenomas was analyzed by ALDH1A1 immunohistochemistry with morphometry, and a replication set of 89 adenomas from 76 high-risk participants was evaluated by computerized image analysis. ALDH1A1-labeling indices (ALI) were similar across patient characteristics and in advanced and nonadvanced adenomas. There was a trend toward higher ALIs in adenomas occurring in the right than left colon (P = 0.09). ALIs of synchronous adenomas were correlated (intraclass correlation coefficient 0.67). Participants in both sample sets who developed a metachronous adenoma had significantly higher ALIs in their baseline adenoma than participants who remained adenoma free. In the replication set, the adjusted odds for metachronous adenoma increased 1.46 for each 10% increase in ALIs (P = 0.03). A best-fit algorithm-based cutoff point of 22.4% had specificity of 75.0% and positive predictive value of 70.0% for metachronous adenoma development. A larger population of ALDH1A1-expressing cells in an adenoma is associated with a higher risk for metachronous adenoma, independent of adenoma size or histopathology. If confirmed, ALDH1A1 has potential as a novel biomarker in risk assessment and as a potential stem cell target for chemoprevention. ©2013 AACR

  7. Awakened by cellular stress: isolation and characterization of a novel population of pluripotent stem cells derived from human adipose tissue.

    Directory of Open Access Journals (Sweden)

    Saleh Heneidi

    Full Text Available Advances in stem cell therapy face major clinical limitations, particularly challenged by low rates of post-transplant cell survival. Hostile host factors of the engraftment microenvironment such as hypoxia, nutrition deprivation, pro-inflammatory cytokines, and reactive oxygen species can each contribute to unwanted differentiation or apoptosis. In this report, we describe the isolation and characterization of a new population of adipose tissue (AT derived pluripotent stem cells, termed Multilineage Differentiating Stress-Enduring (Muse Cells, which are isolated using severe cellular stress conditions, including long-term exposure to the proteolytic enzyme collagenase, serum deprivation, low temperatures and hypoxia. Under these conditions, a highly purified population of Muse-AT cells is isolated without the utilization of cell sorting methods. Muse-AT cells grow in suspension as cell spheres reminiscent of embryonic stem cell clusters. Muse-AT cells are positive for the pluripotency markers SSEA3, TR-1-60, Oct3/4, Nanog and Sox2, and can spontaneously differentiate into mesenchymal, endodermal and ectodermal cell lineages with an efficiency of 23%, 20% and 22%, respectively. When using specific differentiation media, differentiation efficiency is greatly enhanced in Muse-AT cells (82% for mesenchymal, 75% for endodermal and 78% for ectodermal. When compared to adipose stem cells (ASCs, microarray data indicate a substantial up-regulation of Sox2, Oct3/4, and Rex1. Muse-ATs also exhibit gene expression patterns associated with the down-regulation of genes involved in cell death and survival, embryonic development, DNA replication and repair, cell cycle and potential factors related to oncogenecity. Gene expression analysis indicates that Muse-ATs and ASCs are mesenchymal in origin; however, Muse-ATs also express numerous lymphocytic and hematopoietic genes, such as CCR1 and CXCL2, encoding chemokine receptors and ligands involved in stem cell

  8. Derivation of Stromal (Skeletal, Mesenchymal) Stem-like cells from Human Embryonic Stem Cells

    DEFF Research Database (Denmark)

    Mahmood, Amer; Harkness, Linda; Abdallah, Basem

    2012-01-01

    EBs using BMP2 (bone morphogenic protein 2) combined with standard osteoblast induction medium led to weak osteoblastic induction. Conversely, subcutaneous in vivo implantation of day 20 hEBs in immune deficient mice, mixed with hydroxyapatite/tricalcium phosphate (HA/TCP) as an osteoconductive scaffold......Derivation of bone forming cells (osteoblasts) from human embryonic stem cells (hESC) is a pre-requisite for their use in clinical applications. However, there is no standard protocol for differentiating hESC into osteoblastic cells. The aim of this study was to identify the emergence of a human...... stromal (mesenchymal, skeletal) stem cell (hMSC)-like population, known to be osteoblastic cell precursors and to test their osteoblastic differentiation capacity in ex vivo cultures and in vivo. We cultured hESC in a feeder-free environment using serum replacement and as suspension aggregates (embryoid...

  9. Multipotent stem cells of mother's milk

    Directory of Open Access Journals (Sweden)

    Alessandra Reali

    2016-03-01

    Full Text Available In recent years the presence of stem cells (hBSCs: human breastmilk-derived stem cells and epithelial progenitors has been demonstrated in mother’s milk (MM. Stem cells present in samples of fresh MM exhibit a high degree of vitality and this makes possible the performance of cell cultures and to evaluate the differentiation capacity of the hBSCs. The most important datum that expresses the enormous potential of the use of MM stem cells is the presence of a cell population capable of differentiating into the three mesoderm, endoderm and ectoderm lines. The small number of studies and MM samples analyzed and the different sampling methods applied suggest standardization in the collection, analysis and culture of MM in future studies, in consideration of the well-known extreme variability of MM composition, also from the standpoint of cells.The analysis of literature data confirms the uniqueness of MM and its enormous potential.Proceedings of the 2nd International Course on Perinatal Pathology (part of the 11th International Workshop on Neonatology · October 26th-31st, 2015 · Cagliari (Italy · October 31st, 2015 · Stem cells: present and future Guest Editors: Gavino Faa, Vassilios Fanos, Antonio Giordano

  10. Derivation and characterization of human embryonic stem cell lines from the Chinese population

    Institute of Scientific and Technical Information of China (English)

    Zhao Wu; Huimin Dai; Lei Qian; Qing Tian; Lei Xiao; Xiaojun Tan; Hui Li; Lingjun Rao; Lixiazi He; Lei Bao; Jing Liao; Chun Cui; Zhenyu Zuo; Qiao Li

    2011-01-01

    Human embryonic stem cells (hESCs) can self-renew indefinitely and differentiate into all cell types in the human body. Therefore, they are valuable in regenerative medicine, human developmental biology and drug discovery. A number of hESC lines have been derived from the Chinese population,but limited of them are available for research purposes. Here we report the derivation and characterization of two hESC lines derived from human blastocysts of Chinese origin. These hESCs express alkaline phosphatase and hESC-specific markers, including Oct4, Nanog, SSEA-3, SSEA-4,TRA-1-60 and TRA-1-81. They also have high levels of telomerase activity and normal karyotypes. These cells can form embryoid body in vitro and can be differentiated into all three germ layers in vivo by teratoma formation. The newly established hESCs will be distributed for research purposes.The availability of hESC lines from the Chinese population will facilitate studies on the differences in hESCs from different ethnic groups.

  11. Cancer Stem Cell Plasticity as Tumor Growth Promoter and Catalyst of Population Collapse

    Directory of Open Access Journals (Sweden)

    Jan Poleszczuk

    2016-01-01

    Full Text Available It is increasingly argued that cancer stem cells are not a cellular phenotype but rather a transient state that cells can acquire, either through intrinsic signaling cascades or in response to environmental cues. While cancer stem cell plasticity is generally associated with increased aggressiveness and treatment resistance, we set out to thoroughly investigate the impact of different rates of plasticity on early and late tumor growth dynamics and the response to therapy. We develop an agent-based model of cancer stem cell driven tumor growth, in which plasticity is defined as a spontaneous transition between stem and nonstem cancer cell states. Simulations of the model show that plasticity can substantially increase tumor growth rate and invasion. At high rates of plasticity, however, the cells get exhausted and the tumor will undergo spontaneous remission in the long term. In a series of in silico trials, we show that such remission can be facilitated through radiotherapy. The presented study suggests that stem cell plasticity has rather complex, nonintuitive implications on tumor growth and treatment response. Further theoretical, experimental, and integrated studies are needed to fully decipher cancer stem cell plasticity and how it can be harnessed for novel therapeutic approaches.

  12. Autophagy regulates the stemness of cervical cancer stem cells

    Directory of Open Access Journals (Sweden)

    Yang Y

    2017-06-01

    Full Text Available Yi Yang,1,2 Li Yu,1 Jin Li,1 Ya Hong Yuan,1 Xiao Li Wang,1 Shi Rong Yan,1 Dong Sheng Li,1 Yan Ding1 1Hubei Key Laboratory of Embryonic Stem Cell Research, 2Reproductive Center, Taihe Hospital, Hubei University of Medicine, Shiyan, People’s Republic of China Abstract: Cancer stem cells (CSCs are a rare population of multipotent cells with the capacity to self-renew. It has been reported that there are CSCs in cervical cancer cells. Pluripotency-associated (PA transcription factors such as Oct4, Sox2, Nanog and CD44 have been used to isolate CSCs subpopulations. In this study, we showed that autophagy plays an important role in the biological behavior of cervical cancer cells. The expression of the autophagy protein Beclin 1 and LC3B was higher in tumorspheres established from human cervical cancers cell lines (and CaSki than in the parental adherent cells. It was also observed that the basal and starvation-induced autophagy flux was higher in tumorspheres than in the bulk population. Autophagy could regulate the expression level of PA proteins in cervical CSCs. In addition, CRISPR/Cas 9-mediated Beclin 1 knockout enhanced the malignancy of HeLa cells, leading to accumulation of PA proteins and promoted tumorsphere formation. Our findings suggest that autophagy modulates homeostasis of PA proteins, and Beclin 1 is critical for CSC maintenance and tumor development in nude mice. This demonstrates that a prosurvival autophagic pathway is critical for CSC maintenance. Keywords: cervical cancer, autophagy, cancer stem cell, LC3, Oct4

  13. Heterogeneity of functional properties of Clone 66 murine breast cancer cells expressing various stem cell phenotypes.

    Science.gov (United States)

    Mukhopadhyay, Partha; Farrell, Tracy; Sharma, Gayatri; McGuire, Timothy R; O'Kane, Barbara; Sharp, J Graham

    2013-01-01

    Breast cancer grows, metastasizes and relapses from rare, therapy resistant cells with a stem cell phenotype (cancer stem cells/CSCs). However, there is a lack of studies comparing the functions of CSCs isolated using different phenotypes in order to determine if CSCs are homogeneous or heterogeneous. Cells with various stem cell phenotypes were isolated by sorting from Clone 66 murine breast cancer cells that grow orthotopically in immune intact syngeneic mice. These populations were compared by in vitro functional assays for proliferation, growth, sphere and colony formation; and in vivo limiting dilution analysis of tumorigenesis. The proportion of cells expressing CD44(high)CD24(low/neg), side population (SP) cells, ALDH1(+), CD49f(high), CD133(high), and CD34(high) differed, suggesting heterogeneity. Differences in frequency and size of tumor spheres from these populations were observed. Higher rates of proliferation of non-SP, ALDH1(+), CD34(low), and CD49f(high) suggested properties of transit amplifying cells. Colony formation was higher from ALDH1(-) and non-SP cells than ALDH1(+) and SP cells suggesting a progenitor phenotype. The frequency of clonal colonies that grew in agar varied and was differentially altered by the presence of Matrigel™. In vivo, fewer cells with a stem cell phenotype were needed for tumor formation than "non-stem" cells. Fewer SP cells were needed to form tumors than ALDH1(+) cells suggesting further heterogeneities of cells with stem phenotypes. Different levels of cytokines/chemokines were produced by Clone 66 with RANTES being the highest. Whether the heterogeneity reflects soluble factor production remains to be determined. These data demonstrate that Clone 66 murine breast cancer cells that express stem cell phenotypes are heterogeneous and exhibit different functional properties, and this may also be the case for human breast cancer stem cells.

  14. Haematopoietic stem and progenitor cells from human pluripotent stem cells

    Science.gov (United States)

    Sugimura, Ryohichi; Jha, Deepak Kumar; Han, Areum; Soria-Valles, Clara; da Rocha, Edroaldo Lummertz; Lu, Yi-Fen; Goettel, Jeremy A.; Serrao, Erik; Rowe, R. Grant; Malleshaiah, Mohan; Wong, Irene; Sousa, Patricia; Zhu, Ted N.; Ditadi, Andrea; Keller, Gordon; Engelman, Alan N.; Snapper, Scott B.; Doulatov, Sergei; Daley, George Q.

    2018-01-01

    A variety of tissue lineages can be differentiated from pluripotent stem cells by mimicking embryonic development through stepwise exposure to morphogens, or by conversion of one differentiated cell type into another by enforced expression of master transcription factors. Here, to yield functional human haematopoietic stem cells, we perform morphogen-directed differentiation of human pluripotent stem cells into haemogenic endothelium followed by screening of 26 candidate haematopoietic stem-cell-specifying transcription factors for their capacity to promote multi-lineage haematopoietic engraftment in mouse hosts. We recover seven transcription factors (ERG, HOXA5, HOXA9, HOXA10, LCOR, RUNX1 and SPI1) that are sufficient to convert haemogenic endothelium into haematopoietic stem and progenitor cells that engraft myeloid, B and T cells in primary and secondary mouse recipients. Our combined approach of morphogen-driven differentiation and transcription-factor-mediated cell fate conversion produces haematopoietic stem and progenitor cells from pluripotent stem cells and holds promise for modelling haematopoietic disease in humanized mice and for therapeutic strategies in genetic blood disorders. PMID:28514439

  15. Depletion of endogenous germ cells in tree shrews in preparation for spermatogonial transplantation.

    Science.gov (United States)

    Liu, Tingting; Guo, Ying; Yan, Lanzhen; Sun, Bin; Zheng, Ping; Zhao, Xudong

    2017-09-01

    To achieve successful spermatogonial transplantation, endogenous germ cells must be depleted in recipient animals to allow donor germ cells to colonize efficiently. Busulfan is commonly used for the depletion of endogenous germ cells in recipient males. However, the optimal dose of busulfan is species-specific, and the optimal dose in tree shrews is yet to be determined. The current study aimed to determine the optimal dose of busulfan for effective suppression of endogenous spermatogenesis in tree shrews. Different doses (15, 20, 25, 30, 35, 40 and 45 mg/kg) of busulfan were injected into tree shrews intraperitoneally. Survival rates of the different treatment groups were calculated at 2 weeks and body weights were measured at 4, 6, 8, 10 and 28 weeks post-busulfan treatment. The testes were also removed and weighed at 4, 6, 8, 10 and 28 weeks post-treatment, and the cross and longitude diameters of the testes and diameters of the seminiferous tubules were measured and histologically evaluated. It was observed that there were no significant differences in the survival rates between the 15-35 mg/kg treatment groups and the control group (P>0.05), while the survival rate of the 40 mg/kg treatment group significantly decreased relative to the control group (Pendogenous germ cells in tree shrews. This dose led to maximum suppression of endogenous spermatogenesis while maintaining an acceptable survival rate of >50% of the lethal dose of busulfan for tree shrews.

  16. Clonal analysis of stem cells in differentiation and disease.

    Science.gov (United States)

    Colom, Bartomeu; Jones, Philip H

    2016-12-01

    Tracking the fate of individual cells and their progeny by clonal analysis has redefined the concept of stem cells and their role in health and disease. The maintenance of cell turnover in adult tissues is achieved by the collective action of populations of stem cells with an equal likelihood of self-renewal or differentiation. Following injury stem cells exhibit striking plasticity, switching from homeostatic behavior in order to repair damaged tissues. The effects of disease states on stem cells are also being uncovered, with new insights into how somatic mutations trigger clonal expansion in early neoplasia. Copyright © 2016 The Author(s). Published by Elsevier Ltd.. All rights reserved.

  17. Foxl1-Expressing Mesenchymal Cells Constitute the Intestinal Stem Cell NicheSummary

    Directory of Open Access Journals (Sweden)

    Reina Aoki

    2016-03-01

    Full Text Available Background & Aims: Intestinal epithelial stem cells that express leucine-rich repeat-containing G-protein coupled receptor 5 (Lgr5 and/or B cell specific Moloney murine leukemia virus integration site 1 (Bmi1 continuously replicate and generate differentiated cells throughout life. Previously, Paneth cells were suggested to constitute an epithelium-intrinsic niche that regulates the behavior of these stem cells. However, ablating Paneth cells has no effect on the maintenance of functional stem cells. Here, we show definitively that a small subset of mesenchymal subepithelial cells expressing the winged-helix transcription factor forkhead box l1 (Foxl1 are a critical component of the intestinal stem cell niche. Methods: We genetically ablated Foxl1+ mesenchymal cells in adult mice using 2 separate models by expressing either the human or simian diphtheria toxin receptor under Foxl1 promoter control. Conclusions: Killing Foxl1+ cells by diphtheria toxin administration led to an abrupt cessation of proliferation of both epithelial stem- and transit-amplifying progenitor cell populations that was associated with a loss of active Wnt signaling to the intestinal epithelium. Therefore, Foxl1-expressing mesenchymal cells constitute the fundamental niche for intestinal stem cells. Keywords: Intestinal Stem Cell Niche, Wnt, Mesenchyme

  18. CRISPR/Cas9-Mediated Deletion of C1EIS Inhibits Chicken Embryonic Stem Cell Differentiation Into Male Germ Cells (Gallus gallus).

    Science.gov (United States)

    Zuo, Qisheng; Jin, Kai; Wang, Yingjie; Song, Jiuzhou; Zhang, Yani; Li, Bichun

    2017-08-01

    We previously found that C1EIS is preferentially expressed in Chicken spermatogonial stem cells (SSCs) by RNA sequencing (RNA-seq), so our current study focused on C1EIS's role in Chicken embryonic stem cells (ESCs) differentiation into male germ cells. We constructed a CRISPR/Cas9 vector targeting C1EIS. T7 endonuclease I (T7EI) digestion method and sequencing of TA cloning were used to detect the knock-out efficiency of the Single guide RNA (sgRNA) after the cas9/gRNA vector transfected into D fibroblasts 1(DF-1), ESCs, and Chicken embryos. The results showed that CRISPR/Cas9 gene knockout efficiency is about 40%. Differentiation of the targeted ESCs into SSCs was inhibited at the embryoid body stage due to C1EIS deficiency. Immunofluorescent staining revealed that the mutagenized ESCs (RA (Retinoic Acid) with C1EIS Knock out) expressed lower levels of integrin α6 and integrin β1 compared to wild type cells. Quantitative real-time PCR (QRT-PCR) revealed Oct4 and Sox2 expression significantly increased, contrarily integrin β1 and Stra8 expression significantly decreased than RA induced group and RA with C1EIS Overexpression. During retinoic acid-induced differentiation, knockout of C1EIS in ESCs inhibited formation of SSC-like cells, suggesting C1EIS plays a vital role in promoting differentiation of avian ESCs to SSCs by regulating expression of multiple pluripotency-related genes. J. Cell. Biochem. 118: 2380-2386, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  19. Differentiation and molecular profiling of human embryonic stem cell-derived corneal epithelial cells.

    Science.gov (United States)

    Brzeszczynska, J; Samuel, K; Greenhough, S; Ramaesh, K; Dhillon, B; Hay, D C; Ross, J A

    2014-06-01

    It has been suggested that the isolation of scalable populations of limbal stem cells may lead to radical changes in ocular therapy. In particular, the derivation and transplantation of corneal stem cells from these populations may result in therapies providing clinical normality of the diseased or damaged cornea. Although feasible in theory, the lack of donor material in sufficient quantity and quality currently limits such a strategy. A potential scalable source of corneal cells could be derived from pluripotent stem cells (PSCs). We developed an in vitro and serum-free corneal differentiation model which displays significant promise. Our stepwise differentiation model was designed with reference to development and gave rise to cells which displayed similarities to epithelial progenitor cells which can be specified to cells displaying a corneal epithelial phenotype. We believe our approach is novel, provides a robust model of human development and in the future, may facilitate the generation of corneal epithelial cells that are suitable for clinical use. Additionally, we demonstrate that following continued cell culture, stem cell-derived corneal epithelial cells undergo transdifferentiation and exhibit squamous metaplasia and therefore, also offer an in vitro model of disease.

  20. The developing cancer stem-cell model: clinical challenges and opportunities

    NARCIS (Netherlands)

    Vermeulen, Louis; de Sousa E Melo, Felipe; Richel, Dick J.; Medema, Jan Paul

    2012-01-01

    During the past decade, a stem-cell-like subset of cancer cells has been identified in many malignancies. These cells, referred to as cancer stem cells (CSCs), are of particular interest because they are believed to be the clonogenic core of the tumour and therefore represent the cell population

  1. Dissecting stem cell differentiation using single cell expression profiling

    OpenAIRE

    Moignard, Victoria Rachel; Göttgens, Berthold

    2016-01-01

    Many assumptions about the way cells behave are based on analyses of populations. However, it is now widely recognized that even apparently pure populations can display a remarkable level of heterogeneity. This is particularly true in stem cell biology where it hinders our understanding of normal development and the development of strategies for regenerative medicine. Over the past decade technologies facilitating gene expression analysis at the single cell level have become widespread, provi...

  2. Identification and characterization of cancer stem cells in human head and neck squamous cell carcinoma

    International Nuclear Information System (INIS)

    Han, Jing; Fujisawa, Toshio; Husain, Syed R; Puri, Raj K

    2014-01-01

    Current evidence suggests that initiation, growth, and invasion of cancer are driven by a small population of cancer stem cells (CSC). Previous studies have identified CD44+ cells as cancer stem cells in head and neck squamous cell carcinoma (HNSCC). However, CD44 is widely expressed in most cells in HNSCC tumor samples and several cell lines tested. We previously identified a small population of CD24+/CD44+ cells in HNSCC. In this study, we examined whether this population of cells may represent CSC in HNSCC. CD24+/CD44+ cells from HNSCC cell lines were sorted by flow cytometry, and their phenotype was confirmed by qRT-PCR. Their self-renewal and differentiation properties, clonogenicity in collagen gels, and response to anticancer drugs were tested in vitro. The tumorigenicity potential of CD24+/CD44+ cells was tested in athymic nude mice in vivo. Our results show that CD24+/CD44+ cells possessed stemness characteristics of self-renewal and differentiation. CD24+/CD44+ cells showed higher cell invasion in vitro and made higher number of colonies in collagen gels compared to CD24-/CD44+ HNSCC cells. In addition, the CD24+/CD44+ cells were more chemo-resistant to gemcitabine and cisplatin compared to CD24-/CD44+ cells. In vivo, CD24+/CD44+ cells showed a tendency to generate larger tumors in nude mice compared to CD24-/CD44+ cell population. Our study clearly demonstrates that a distinct small population of CD24+/CD44+ cells is present in HNSCC that shows stem cell-like properties. This distinct small population of cells should be further characterized and may provide an opportunity to target HNSCC CSC for therapy

  3. Evaluation of hollow fiber culture for large-scale production of mouse embryonic stem cell-derived hematopoietic stem cells.

    Science.gov (United States)

    Nakano, Yu; Iwanaga, Shinya; Mizumoto, Hiroshi; Kajiwara, Toshihisa

    2018-03-03

    Hematopoietic stem cells (HSCs) have the ability to differentiate into all types of blood cells and can be transplanted to treat blood disorders. However, it is difficult to obtain HSCs in large quantities because of the shortage of donors. Recent efforts have focused on acquiring HSCs by differentiation of pluripotent stem cells. As a conventional differentiation method of pluripotent stem cells, the formation of embryoid bodies (EBs) is often employed. However, the size of EBs is limited by depletion of oxygen and nutrients, which prevents them from being efficient for the production of HSCs. In this study, we developed a large-scale hematopoietic differentiation approach for mouse embryonic stem (ES) cells by applying a hollow fiber (HF)/organoid culture method. Cylindrical organoids, which had the potential for further spontaneous differentiation, were established inside of hollow fibers. Using this method, we improved the proliferation rate of mouse ES cells to produce an increased HSC population and achieved around a 40-fold higher production volume of HSCs in HF culture than in conventional EB culture. Therefore, the HF/organoid culture method may be a new mass culture method to acquire pluripotent stem cell-derived HSCs.

  4. Learn About Stem Cells

    Science.gov (United States)

    ... Patient Handbook Stem Cell Glossary Search Toggle Nav Stem Cell Basics Stem cells are the foundation from which ... original cell’s DNA, cytoplasm and cell membrane. About stem cells Stem cells are the foundation of development in ...

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

    Science.gov (United States)

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

    2017-02-01

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

  6. Fake news portrayals of stem cells and stem cell research.

    Science.gov (United States)

    Marcon, Alessandro R; Murdoch, Blake; Caulfield, Timothy

    2017-10-01

    This study examines how stem cells and stem cell research are portrayed on websites deemed to be purveyors of distorted and dubious information. Content analysis was conducted on 224 articles from 2015 to 2016, compiled by searching with the keywords 'stem cell(s)' on a list of websites flagged for containing either 'fake' or 'junk science' news. Articles contained various exaggerated positive and negative claims about stem cells and stem cell science, health and science related conspiracy theories, and statements promoting fear and mistrust of conventional medicine. Findings demonstrate the existence of organized misinformation networks, which may lead the public away from accurate information and facilitate a polarization of public discourse.

  7. Muscle Stem Cells: A Model System for Adult Stem Cell Biology.

    Science.gov (United States)

    Cornelison, Ddw; Perdiguero, Eusebio

    2017-01-01

    Skeletal muscle stem cells, originally termed satellite cells for their position adjacent to differentiated muscle fibers, are absolutely required for the process of skeletal muscle repair and regeneration. In the last decade, satellite cells have become one of the most studied adult stem cell systems and have emerged as a standard model not only in the field of stem cell-driven tissue regeneration but also in stem cell dysfunction and aging. Here, we provide background in the field and discuss recent advances in our understanding of muscle stem cell function and dysfunction, particularly in the case of aging, and the potential involvement of muscle stem cells in genetic diseases such as the muscular dystrophies.

  8. A new and fast technique to generate offspring after germ cells transplantation in adult fish: the Nile tilapia (Oreochromis niloticus model.

    Directory of Open Access Journals (Sweden)

    Samyra M S N Lacerda

    Full Text Available BACKGROUND: Germ cell transplantation results in fertile recipients and is the only available approach to functionally investigate the spermatogonial stem cell biology in mammals and probably in other vertebrates. In the current study, we describe a novel non-surgical methodology for efficient spermatogonial transplantation into the testes of adult tilapia (O. niloticus, in which endogenous spermatogenesis had been depleted with the cytostatic drug busulfan. METHODOLOGY/PRINCIPAL FINDINGS: Using two different tilapia strains, the production of fertile spermatozoa with donor characteristics was demonstrated in adult recipient, which also sired progeny with the donor genotype. Also, after cryopreservation tilapia spermatogonial cells were able to differentiate to spermatozoa in the testes of recipient fishes. These findings indicate that injecting germ cells directly into adult testis facilitates and enable fast generation of donor spermatogenesis and offspring compared to previously described methods. CONCLUSION: Therefore, a new suitable methodology for biotechnological investigations in aquaculture was established, with a high potential to improve the production of commercially valuable fish, generate transgenic animals and preserve endangered fish species.

  9. Some applications of nanotechnologies in stem cells research

    International Nuclear Information System (INIS)

    Belicchi, M.; Cancedda, R.; Cedola, A.; Fiori, F.; Gavina, M.; Giuliani, A.; Komlev, V.S.; Lagomarsino, S.; Mastrogiacomo, M.; Renghini, C.; Rustichelli, F.

    2009-01-01

    Stem cell based tissue engineering therapies involve the administration of ex vivo manipulated stem cell populations with the purpose of repairing and regenerating damaged or diseased tissue. Currently available methods of monitoring transplanted cells are quite limited. To monitor the outcomes of stem cell therapy longitudinally requires the development of non-destructive strategies that are capable of identifying the location, magnitude, and duration of cellular survival and fate. The recent development of imaging techniques offers great potential to address these critical issues by non-invasively tracking the fate of the transplanted cells. This review offers a focused presentation of some examples of the use of imaging techniques connected to the nanotechnological world in research areas related to stem cells. In particular investigations will be considered concerning tissue-engineered bone, treatment of intervertebral disc degeneration, treatment by human stem cells of muscular dystrophy of Duchenne in small animal models and the repair of spinal cord injuries.

  10. Some applications of nanotechnologies in stem cells research

    Energy Technology Data Exchange (ETDEWEB)

    Belicchi, M. [Fondazione IRCCS Ospedale Policlinico di Milano, Via Francesco Sforza, Milano 20122 (Italy); Cancedda, R. [Istituto Nazionale per la Ricerca sul Cancro and Dipartimento di Oncologia Biologia e Genetica - Universita di Genova, Largo R. Benzi 10, Genova 16132 (Italy); Cedola, A. [Istituto di Fotonica e Nanotecnologie - CNR, Via Cinto Romano 42, Roma 00156 (Italy); Fiori, F. [Dipartimento S.A.I.F.E.T. Sezione di Scienze Fisiche - Universita' Politecnica delle Marche, Via Brecce Bianche, Ancona 60131 (Italy); INBB - Istituto Nazionale Biostrutture e Biosistemi (Italy); CNISM - Matec (Ancona) (Italy); Gavina, M. [Fondazione IRCCS Ospedale Policlinico di Milano, Via Francesco Sforza, Milano 20122 (Italy); Giuliani, A. [Dipartimento S.A.I.F.E.T. Sezione di Scienze Fisiche - Universita' Politecnica delle Marche, Via Brecce Bianche, Ancona 60131 (Italy); CNISM - Matec (Ancona) (Italy); Komlev, V.S. [Dipartimento S.A.I.F.E.T. Sezione di Scienze Fisiche - Universita' Politecnica delle Marche, Via Brecce Bianche, Ancona 60131 (Italy); Institute for Physical Chemistry of Ceramics, Russian Academy of Sciences, Ozernaya 48, 119361 Moscow (Russian Federation); Lagomarsino, S. [Istituto di Fotonica e Nanotecnologie - CNR, Via Cinto Romano 42, Roma 00156 (Italy); Mastrogiacomo, M. [Istituto Nazionale per la Ricerca sul Cancro and Dipartimento di Oncologia Biologia e Genetica - Universita di Genova, Largo R. Benzi 10, Genova 16132 (Italy); Renghini, C. [Dipartimento S.A.I.F.E.T. Sezione di Scienze Fisiche - Universita' Politecnica delle Marche, Via Brecce Bianche, Ancona 60131 (Italy); INBB - Istituto Nazionale Biostrutture e Biosistemi (Italy); CNISM - Matec (Ancona) (Italy); Rustichelli, F., E-mail: f.rustichelli@univpm.i [Dipartimento S.A.I.F.E.T. Sezione di Scienze Fisiche - Universita' Politecnica delle Marche, Via Brecce Bianche, Ancona 60131 (Italy); INBB - Istituto Nazionale Biostrutture e Biosistemi (Italy); CNISM - Matec (Ancona) (Italy)

    2009-12-15

    Stem cell based tissue engineering therapies involve the administration of ex vivo manipulated stem cell populations with the purpose of repairing and regenerating damaged or diseased tissue. Currently available methods of monitoring transplanted cells are quite limited. To monitor the outcomes of stem cell therapy longitudinally requires the development of non-destructive strategies that are capable of identifying the location, magnitude, and duration of cellular survival and fate. The recent development of imaging techniques offers great potential to address these critical issues by non-invasively tracking the fate of the transplanted cells. This review offers a focused presentation of some examples of the use of imaging techniques connected to the nanotechnological world in research areas related to stem cells. In particular investigations will be considered concerning tissue-engineered bone, treatment of intervertebral disc degeneration, treatment by human stem cells of muscular dystrophy of Duchenne in small animal models and the repair of spinal cord injuries.

  11. A muscle stem cell for every muscle: variability of satellite cell biology among different muscle groups

    Science.gov (United States)

    Randolph, Matthew E.; Pavlath, Grace K.

    2015-01-01

    The human body contains approximately 640 individual skeletal muscles. Despite the fact that all of these muscles are composed of striated muscle tissue, the biology of these muscles and their associated muscle stem cell populations are quite diverse. Skeletal muscles are affected differentially by various muscular dystrophies (MDs), such that certain genetic mutations specifically alter muscle function in only a subset of muscles. Additionally, defective muscle stem cells have been implicated in the pathology of some MDs. The biology of muscle stem cells varies depending on the muscles with which they are associated. Here we review the biology of skeletal muscle stem cell populations of eight different muscle groups. Understanding the biological variation of skeletal muscles and their resident stem cells could provide valuable insight into mechanisms underlying the susceptibility of certain muscles to myopathic disease. PMID:26500547

  12. Metabolism and the Control of Cell Fate Decisions and Stem Cell Renewal

    Science.gov (United States)

    Ito, Kyoko; Ito, Keisuke

    2016-01-01

    Although the stem cells of various tissues remain in the quiescent state to maintain their undifferentiated state, they also undergo cell divisions as required, and if necessary, even a single stem cell is able to provide for lifelong tissue homeostasis. Stem cell populations are precisely controlled by the balance between their symmetric and asymmetric divisions, with their division patterns determined by whether the daughter cells involved retain their self-renewal capacities. Recent studies have reported that metabolic pathways and the distribution of mitochondria are regulators of the division balance of stem cells and that metabolic defects can shift division balance toward symmetric commitment, which leads to stem cell exhaustion. It has also been observed that in asymmetric division, old mitochondria, which are central metabolic organelles, are segregated to the daughter cell fated to cell differentiation, whereas in symmetric division, young and old mitochondria are equally distributed between both daughter cells. Thus, metabolism and mitochondrial biology play important roles in stem cell fate decisions. As these decisions directly affect tissue homeostasis, understanding their regulatory mechanisms in the context of cellular metabolism is critical. PMID:27482603

  13. Stem Cell Pathology.

    Science.gov (United States)

    Fu, Dah-Jiun; Miller, Andrew D; Southard, Teresa L; Flesken-Nikitin, Andrea; Ellenson, Lora H; Nikitin, Alexander Yu

    2018-01-24

    Rapid advances in stem cell biology and regenerative medicine have opened new opportunities for better understanding disease pathogenesis and the development of new diagnostic, prognostic, and treatment approaches. Many stem cell niches are well defined anatomically, thereby allowing their routine pathological evaluation during disease initiation and progression. Evaluation of the consequences of genetic manipulations in stem cells and investigation of the roles of stem cells in regenerative medicine and pathogenesis of various diseases such as cancer require significant expertise in pathology for accurate interpretation of novel findings. Therefore, there is an urgent need for developing stem cell pathology as a discipline to facilitate stem cell research and regenerative medicine. This review provides examples of anatomically defined niches suitable for evaluation by diagnostic pathologists, describes neoplastic lesions associated with them, and discusses further directions of stem cell pathology.

  14. Heterogeneous Stem Cells in Skin Homeostatis and Wound Repair

    Directory of Open Access Journals (Sweden)

    Anna Meilana

    2015-08-01

    Full Text Available BACKGROUND: The skin protects mammals from insults, infection and dehydration and enables thermoregulation and sensory perception. Various skin-resident cells carry out these diverse functions. Constant turnover of cells and healing upon injury necessitate multiple reservoirs of stem cells. The skin is a complex organ harboring several distinct populations of stem cells and a rich array of cell types. Advances in genetic and imaging tools have brought new findings about the lineage relationships between skin stem cells and their progeny. Such knowledge may offer novel avenues for therapeutics and regenerative medicine. CONTENT: In the past years, our view of the mechanisms that govern skin homeostasis and regeneration have markedly changed. New populations of stem cells have been identified that behave spatio-temporally differently in healthy tissues and in situations of damage, indicating that a great level of stem cell heterogeneity is present in the skin. There are believed to be distinct populations of stem cells in different locations. The lineages that they feed are normally constrained by signals from their local environment, but they can give rise to all epidermal lineages in response to appropriate stimuli. Given the richness of structures such as blood vessels, subcutaneous fat, innervation and the accumulation of fibroblasts under the upper parts of the rete ridges (in the case of human skin, it is reasonable to speculate that the microenvironment might be essential for interfollicular epidermal homeostasis. The bloodstream is probably the main source of long-range signals reaching the skin, and cues provided by the vascular niche might be essential for skin homeostasis. SUMMARY: A key function of the interfollicular epidermis is to act as a protective interface between the body and the external environment, and it contains several architectural elements that enable it to fulfill this function. All elements of the epidermis play

  15. A Novel View of the Adult Stem Cell Compartment From the Perspective of a Quiescent Population of Very Small Embryonic-Like Stem Cells.

    Science.gov (United States)

    Ratajczak, Mariusz Z; Ratajczak, Janina; Suszynska, Malwina; Miller, Donald M; Kucia, Magda; Shin, Dong-Myung

    2017-01-06

    Evidence has accumulated that adult hematopoietic tissues and other organs contain a population of dormant stem cells (SCs) that are more primitive than other, already restricted, monopotent tissue-committed SCs (TCSCs). These observations raise several questions, such as the developmental origin of these cells, their true pluripotent or multipotent nature, which surface markers they express, how they can be efficiently isolated from adult tissues, and what role they play in the adult organism. The phenotype of these cells and expression of some genes characteristic of embryonic SCs, epiblast SCs, and primordial germ cells suggests their early-embryonic deposition in developing tissues as precursors of adult SCs. In this review, we will critically discuss all these questions and the concept that small dormant SCs related to migratory primordial germ cells, described as very small embryonic-like SCs, are deposited during embryogenesis in bone marrow and other organs as a backup population for adult tissue-committed SCs and are involved in several processes related to tissue or organ rejuvenation, aging, and cancerogenesis. The most recent results on successful ex vivo expansion of human very small embryonic-like SC in chemically defined media free from feeder-layer cells open up new and exciting possibilities for their application in regenerative medicine. © 2017 American Heart Association, Inc.

  16. The neural crest is a source of mesenchymal stem cells with specialized hematopoietic stem cell niche function.

    Science.gov (United States)

    Isern, Joan; García-García, Andrés; Martín, Ana M; Arranz, Lorena; Martín-Pérez, Daniel; Torroja, Carlos; Sánchez-Cabo, Fátima; Méndez-Ferrer, Simón

    2014-09-25

    Mesenchymal stem cells (MSCs) and osteolineage cells contribute to the hematopoietic stem cell (HSC) niche in the bone marrow of long bones. However, their developmental relationships remain unclear. In this study, we demonstrate that different MSC populations in the developing marrow of long bones have distinct functions. Proliferative mesoderm-derived nestin(-) MSCs participate in fetal skeletogenesis and lose MSC activity soon after birth. In contrast, quiescent neural crest-derived nestin(+) cells preserve MSC activity, but do not generate fetal chondrocytes. Instead, they differentiate into HSC niche-forming MSCs, helping to establish the HSC niche by secreting Cxcl12. Perineural migration of these cells to the bone marrow requires the ErbB3 receptor. The neonatal Nestin-GFP(+) Pdgfrα(-) cell population also contains Schwann cell precursors, but does not comprise mature Schwann cells. Thus, in the developing bone marrow HSC niche-forming MSCs share a common origin with sympathetic peripheral neurons and glial cells, and ontogenically distinct MSCs have non-overlapping functions in endochondrogenesis and HSC niche formation.

  17. Epirubicin-adsorbed nanodiamonds kill chemoresistant hepatic cancer stem cells.

    Science.gov (United States)

    Wang, Xin; Low, Xinyi Casuarine; Hou, Weixin; Abdullah, Lissa Nurrul; Toh, Tan Boon; Mohd Abdul Rashid, Masturah; Ho, Dean; Chow, Edward Kai-Hua

    2014-12-23

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

  18. Potential Use of Human Periapical Cyst-Mesenchymal Stem Cells (hPCy-MSCs) as a Novel Stem Cell Source for Regenerative Medicine Applications.

    Science.gov (United States)

    Tatullo, Marco; Codispoti, Bruna; Pacifici, Andrea; Palmieri, Francesca; Marrelli, Massimo; Pacifici, Luciano; Paduano, Francesco

    2017-01-01

    Mesenchymal stem cells (MSCs) are attracting growing interest by the scientific community due to their huge regenerative potential. Thus, the plasticity of MSCs strongly suggests the utilization of these cells for regenerative medicine applications. The main issue about the clinical use of MSCs is related to the complex way to obtain them from healthy tissues; this topic has encouraged scientists to search for novel and more advantageous sources of these cells in easily accessible tissues. The oral cavity hosts several cell populations expressing mesenchymal stem cell like-features, furthermore, the access to oral and dental tissues is simple and isolation of cells is very efficient. Thus, oral-derived stem cells are highly attractive for clinical purposes. In this context, human periapical cyst mesenchymal stem cells (hPCy-MSCs) exhibit characteristics similar to other dental-derived MSCs, including their extensive proliferative potential, cell surface marker profile and the ability to differentiate into various cell types such as osteoblasts, adipocytes and neurons. Importantly, hPCy-MSCs are easily collected from the surgically removed periapical cysts; this reusing of biological waste guarantees a smart source of stem cells without any impact on the surrounding healthy tissues. In this review, we report the most interesting research topics related to hPCy-MSCs with a newsworthy discussion about the future insights. This newly discovered cell population exhibits interesting and valuable potentialities that could be of high impact in the future regenerative medicine applications.

  19. Potential Use of Human Periapical Cyst-Mesenchymal Stem Cells (hPCy-MSCs as a Novel Stem Cell Source for Regenerative Medicine Applications

    Directory of Open Access Journals (Sweden)

    Marco Tatullo

    2017-12-01

    Full Text Available Mesenchymal stem cells (MSCs are attracting growing interest by the scientific community due to their huge regenerative potential. Thus, the plasticity of MSCs strongly suggests the utilization of these cells for regenerative medicine applications. The main issue about the clinical use of MSCs is related to the complex way to obtain them from healthy tissues; this topic has encouraged scientists to search for novel and more advantageous sources of these cells in easily accessible tissues. The oral cavity hosts several cell populations expressing mesenchymal stem cell like-features, furthermore, the access to oral and dental tissues is simple and isolation of cells is very efficient. Thus, oral-derived stem cells are highly attractive for clinical purposes. In this context, human periapical cyst mesenchymal stem cells (hPCy-MSCs exhibit characteristics similar to other dental-derived MSCs, including their extensive proliferative potential, cell surface marker profile and the ability to differentiate into various cell types such as osteoblasts, adipocytes and neurons. Importantly, hPCy-MSCs are easily collected from the surgically removed periapical cysts; this reusing of biological waste guarantees a smart source of stem cells without any impact on the surrounding healthy tissues. In this review, we report the most interesting research topics related to hPCy-MSCs with a newsworthy discussion about the future insights. This newly discovered cell population exhibits interesting and valuable potentialities that could be of high impact in the future regenerative medicine applications.

  20. Developmental origin and lineage plasticity of endogenous cardiac stem cells

    Science.gov (United States)

    Santini, Maria Paola; Forte, Elvira; Harvey, Richard P.; Kovacic, Jason C.

    2016-01-01

    Over the past two decades, several populations of cardiac stem cells have been described in the adult mammalian heart. For the most part, however, their lineage origins and in vivo functions remain largely unexplored. This Review summarizes what is known about different populations of embryonic and adult cardiac stem cells, including KIT+, PDGFRα+, ISL1+ and SCA1+ cells, side population cells, cardiospheres and epicardial cells. We discuss their developmental origins and defining characteristics, and consider their possible contribution to heart organogenesis and regeneration. We also summarize the origin and plasticity of cardiac fibroblasts and circulating endothelial progenitor cells, and consider what role these cells have in contributing to cardiac repair. PMID:27095490

  1. Niche-dependent development of functional neuronal networks from embryonic stem cell-derived neural populations

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    Siebler Mario

    2009-08-01

    Full Text Available Abstract Background The present work was performed to investigate the ability of two different embryonic stem (ES cell-derived neural precursor populations to generate functional neuronal networks in vitro. The first ES cell-derived neural precursor population was cultivated as free-floating neural aggregates which are known to form a developmental niche comprising different types of neural cells, including neural precursor cells (NPCs, progenitor cells and even further matured cells. This niche provides by itself a variety of different growth factors and extracellular matrix proteins that influence the proliferation and differentiation of neural precursor and progenitor cells. The second population was cultivated adherently in monolayer cultures to control most stringently the extracellular environment. This population comprises highly homogeneous NPCs which are supposed to represent an attractive way to provide well-defined neuronal progeny. However, the ability of these different ES cell-derived immature neural cell populations to generate functional neuronal networks has not been assessed so far. Results While both precursor populations were shown to differentiate into sufficient quantities of mature NeuN+ neurons that also express GABA or vesicular-glutamate-transporter-2 (vGlut2, only aggregate-derived neuronal populations exhibited a synchronously oscillating network activity 2–4 weeks after initiating the differentiation as detected by the microelectrode array technology. Neurons derived from homogeneous NPCs within monolayer cultures did merely show uncorrelated spiking activity even when differentiated for up to 12 weeks. We demonstrated that these neurons exhibited sparsely ramified neurites and an embryonic vGlut2 distribution suggesting an inhibited terminal neuronal maturation. In comparison, neurons derived from heterogeneous populations within neural aggregates appeared as fully mature with a dense neurite network and punctuated

  2. Stem cell sources for cardiac regeneration

    NARCIS (Netherlands)

    Roccio, M.; Goumans, M. J.; Sluijter, J. P. G.; Doevendans, P. A.

    Cell-based cardiac repair has the ambitious aim to replace the malfunctioning cardiac muscle developed after myocardial infarction, with new contractile cardiomyocytes and vessels. Different stem cell populations have been intensively studied in the last decade as a potential source of new

  3. Simultaneous detection of mRNA and protein stem cell markers in live cells

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    Bao Gang

    2009-04-01

    Full Text Available Abstract Background Biological studies and medical application of stem cells often require the isolation of stem cells from a mixed cell population, including the detection of cancer stem cells in tumor tissue, and isolation of induced pluripotent stem cells after eliciting the expression of specific genes in adult cells. Here we report the detection of Oct-4 mRNA and SSEA-1 protein in live carcinoma stem cells using respectively molecular beacon and dye-labeled antibody, aiming to establish a new method for stem cells detection and isolation. Results Quantification of Oct-4 mRNA and protein in P19 mouse carcinoma stem cells using respectively RT-PCR and immunocytochemistry confirmed that their levels drastically decreased after differentiation. To visualize Oct-4 mRNA in live stem cells, molecular beacons were designed, synthesized and validated, and the detection specificity was confirmed using control studies. We found that the fluorescence signal from Oct-4-targeting molecular beacons provides a clear discrimination between undifferentiated and retinoic acid-induced differentiated cells. Using deconvolution fluorescence microscopy, Oct-4 mRNAs were found to reside on one side of the cytosol. We demonstrated that, using a combination of Oct-4 mRNA-targeting molecular beacon with SSEA-1 antibody in flow cytometric analysis, undifferentiated stem cells can be clearly distinguished from differentiated cells. We revealed that Oct-4 targeting molecular beacons do not seem to affect stem cell biology. Conclusion Molecular beacons have the potential to provide a powerful tool for highly specific detection and isolation of stem cells, including cancer stem cells and induced pluripotent stem (iPS cells without disturbing cell physiology. It is advantageous to perform simultaneous detection of intracellular (mRNA and cell-surface (protein stem cell markers in flow cytometric analysis, which may lead to high detection sensitivity and efficiency.

  4. Purification of human induced pluripotent stem cell-derived neural precursors using magnetic activated cell sorting.

    Science.gov (United States)

    Rodrigues, Gonçalo M C; Fernandes, Tiago G; Rodrigues, Carlos A V; Cabral, Joaquim M S; Diogo, Maria Margarida

    2015-01-01

    Neural precursor (NP) cells derived from human induced pluripotent stem cells (hiPSCs), and their neuronal progeny, will play an important role in disease modeling, drug screening tests, central nervous system development studies, and may even become valuable for regenerative medicine treatments. Nonetheless, it is challenging to obtain homogeneous and synchronously differentiated NP populations from hiPSCs, and after neural commitment many pluripotent stem cells remain in the differentiated cultures. Here, we describe an efficient and simple protocol to differentiate hiPSC-derived NPs in 12 days, and we include a final purification stage where Tra-1-60+ pluripotent stem cells (PSCs) are removed using magnetic activated cell sorting (MACS), leaving the NP population nearly free of PSCs.

  5. Isolation and characterization of neural stem cells from human fetal striatum

    International Nuclear Information System (INIS)

    Li Xiaoxia; Xu Jinchong; Bai Yun; Wang Xuan; Dai Xin; Liu Yinan; Zhang Jun; Zou Junhua; Shen Li; Li Lingsong

    2005-01-01

    This paper described that neural stem cells (hsNSCs) were isolated and expanded rapidly from human fetal striatum in adherent culture. The population was serum- and growth factor-dependent and expressed neural stem cell markers. They were capable of multi-differentiation into neurons, astrocytes, and oligodendrocytes. When plated in the dopaminergic neuron inducing medium, human striatum neural stem cells could differentiate into tyrosine hydroxylase positive neurons. hsNSCs were morphologically homogeneous and possessed high proliferation ability. The population doubled every 44.28 h and until now it has divided for more than 82 generations in vitro. Normal human diploid karyotype was unchanged throughout the in vitro culture period. Together, this study has exploited a method for continuous and rapid expansion of human neural stem cells as pure population, which maintained the capacity to generate almost fifty percent neurons. The availability of such cells may hold great interest for basic and applied neuroscience

  6. EGFR/Src/Akt signaling modulates Sox2 expression and self-renewal of stem-like side-population cells in non-small cell lung cancer.

    Science.gov (United States)

    Singh, Sandeep; Trevino, Jose; Bora-Singhal, Namrata; Coppola, Domenico; Haura, Eric; Altiok, Soner; Chellappan, Srikumar P

    2012-09-25

    Cancer stem cells are thought to be responsible for the initiation and progression of cancers. In non-small cell lung cancers (NSCLCs), Hoechst 33342 dye effluxing side population (SP) cells are shown to have stem cell like properties. The oncogenic capacity of cancer stem-like cells is in part due to their ability to self-renew; however the mechanistic correlation between oncogenic pathways and self-renewal of cancer stem-like cells has remained elusive. Here we characterized the SP cells at the molecular level and evaluated its ability to generate tumors at the orthotopic site in the lung microenvironment. Further, we investigated if the self-renewal of SP cells is dependent on EGFR mediated signaling. SP cells were detected and isolated from multiple NSCLC cell lines (H1650, H1975, A549), as well as primary human tumor explants grown in nude mice. SP cells demonstrated stem-like properties including ability to self-renew and grow as spheres; they were able to generate primary and metastatic tumors upon orthotopic implantation into the lung of SCID mice. In vitro study revealed elevated expression of stem cell associated markers like Oct4, Sox2 and Nanog as well as demonstrated intrinsic epithelial to mesenchymal transition features in SP cells. Further, we show that abrogation of EGFR, Src and Akt signaling through pharmacological or genetic inhibitors suppresses the self-renewal growth and expansion of SP-cells and resulted in specific downregulation of Sox2 protein expression. siRNA mediated depletion of Sox2 significantly blocked the SP phenotype as well as its self-renewal capacity; whereas other transcription factors like Oct4 and Nanog played a relatively lesser role in regulating self-renewal. Interestingly, Sox2 was elevated in metastatic foci of human NSCLC samples. Our findings suggest that Sox2 is a novel target of EGFR-Src-Akt signaling in NSCLCs that modulates self-renewal and expansion of stem-like cells from NSCLC. Therefore, the outcome of the

  7. EGFR/Src/Akt signaling modulates Sox2 expression and self-renewal of stem-like side-population cells in non-small cell lung cancer

    Directory of Open Access Journals (Sweden)

    Singh Sandeep

    2012-09-01

    Full Text Available Abstract Background Cancer stem cells are thought to be responsible for the initiation and progression of cancers. In non-small cell lung cancers (NSCLCs, Hoechst 33342 dye effluxing side population (SP cells are shown to have stem cell like properties. The oncogenic capacity of cancer stem-like cells is in part due to their ability to self-renew; however the mechanistic correlation between oncogenic pathways and self-renewal of cancer stem-like cells has remained elusive. Here we characterized the SP cells at the molecular level and evaluated its ability to generate tumors at the orthotopic site in the lung microenvironment. Further, we investigated if the self-renewal of SP cells is dependent on EGFR mediated signaling. Results SP cells were detected and isolated from multiple NSCLC cell lines (H1650, H1975, A549, as well as primary human tumor explants grown in nude mice. SP cells demonstrated stem-like properties including ability to self-renew and grow as spheres; they were able to generate primary and metastatic tumors upon orthotopic implantation into the lung of SCID mice. In vitro study revealed elevated expression of stem cell associated markers like Oct4, Sox2 and Nanog as well as demonstrated intrinsic epithelial to mesenchymal transition features in SP cells. Further, we show that abrogation of EGFR, Src and Akt signaling through pharmacological or genetic inhibitors suppresses the self-renewal growth and expansion of SP-cells and resulted in specific downregulation of Sox2 protein expression. siRNA mediated depletion of Sox2 significantly blocked the SP phenotype as well as its self-renewal capacity; whereas other transcription factors like Oct4 and Nanog played a relatively lesser role in regulating self-renewal. Interestingly, Sox2 was elevated in metastatic foci of human NSCLC samples. Conclusions Our findings suggest that Sox2 is a novel target of EGFR-Src-Akt signaling in NSCLCs that modulates self-renewal and expansion of

  8. Homogeneity evaluation of mesenchymal stem cells based on electrotaxis analysis

    OpenAIRE

    Kim, Min Sung; Lee, Mi Hee; Kwon, Byeong-Ju; Kim, Dohyun; Koo, Min-Ah; Seon, Gyeung Mi; Park, Jong-Chul

    2017-01-01

    Stem cell therapy that can restore function to damaged tissue, avoid host rejection and reduce inflammation throughout body without use of immunosuppressive drugs. The established methods were used to identify and to isolate specific stem cell markers by FACS or by immunomagnetic cell separation. The procedures for distinguishing population of stem cells took a time and needed many preparations. Here we suggest an electrotaxis analysis as a new method to evaluate the homogeneity of mesenchyma...

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

    Science.gov (United States)

    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. Radiation-induced genetic effects in germ cells of mammals

    International Nuclear Information System (INIS)

    Van Buul, P.P.W.

    1993-01-01

    The aim of the project is to gain information on the effects of ionizing radiation on germ cells of rodents and primates as measured by induced chromosomal translocations. Different aspects of the very significant interspecies differences between the mouse and the rhesus monkey (Macaca mulatta) for translocation induction in spermatogonial stem cells were studied. In addition, possible mechanisms for the well established reduced transmission of induced mouse translocations were investigated. (R.P.) 6 refs

  11. Coexistence of Quiescent and Active Adult Stem Cells in Mammals

    NARCIS (Netherlands)

    Li, Linheng; Clevers, Hans

    2010-01-01

    Adult stem cells are crucial for physiological tissue renewal and regeneration after injury. Prevailing models assume the existence of a single quiescent population of stem cells residing in a specialized niche of a given tissue. Emerging evidence indicates that both quiescent (out of cell cycle and

  12. Activin pathway enhances colorectal cancer stem cell self-renew and tumor progression.

    Science.gov (United States)

    Liu, Rui; Wang, Jun-Hua; Xu, Chengxiong; Sun, Bo; Kang, Sa-Ouk

    2016-10-28

    Activin belongs to transforming growth factor (TGF)-β super family of growth and differentiation factors and activin pathway participated in broad range of cell process. Studies elaborated activin pathway maintain pluripotency in human stem cells and suggest that the function of activin/nodal signaling in self-renew would be conserved across embryonic and adult stem cells. In this study, we tried to determine the effect of activin signaling pathway in regulation of cancer stem cells as a potential target for cancer therapy in clinical trials. A population of colorectal cancer cells was selected by the treatment of activin A. This population of cell possessed stem cell character with sphere formation ability. We demonstrated activin pathway enhanced the colorectal cancer stem cells self-renew and contribute to colorectal cancer progression in vivo. Targeting activin pathway potentially provide effective strategy for colorectal cancer therapy. Copyright © 2016 Elsevier Inc. All rights reserved.

  13. Comparative study of adipose-derived stem cells and bone marrow-derived stem cells in similar microenvironmental conditions

    Energy Technology Data Exchange (ETDEWEB)

    Guneta, Vipra [Division of Materials Technology, School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798 (Singapore); Tan, Nguan Soon [School of Biological Science, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551 (Singapore); KK Research Centre, KK Women' s and Children Hospital, 100 Bukit Timah Road, Singapore 229899 (Singapore); Institute of Molecular and Cell Biology, Agency for Science Technology & Research - A*STAR, 61 Biopolis Drive, Proteos, Singapore 138673 (Singapore); Chan, Soon Kiat Jeremy [School of Biological Science, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551 (Singapore); Tanavde, Vivek [Bioinformatics Institute, Agency for Science Technology & Research - A*STAR, 30 Biopolis Street, Matrix, Singapore 138671 (Singapore); Lim, Thiam Chye [Division of Plastic, Reconstructive and Aesthetic Surgery, Department of Surgery, National University Hospital (NUH) and National University of Singapore (NUS), Kent Ridge Wing, Singapore 119074 (Singapore); Wong, Thien Chong Marcus [Plastic, Reconstructive and Aesthetic Surgery Section, Tan Tock Seng Hospital (TTSH), 11, Jalan Tan Tock Seng, Singapore 308433 (Singapore); Choong, Cleo, E-mail: cleochoong@ntu.edu.sg [Division of Materials Technology, School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798 (Singapore); KK Research Centre, KK Women' s and Children Hospital, 100 Bukit Timah Road, Singapore 229899 (Singapore)

    2016-11-01

    Mesenchymal stem cells (MSCs), which were first isolated from the bone marrow, are now being extracted from various other tissues in the body, including the adipose tissue. The current study presents systematic evidence of how the adipose tissue-derived stem cells (ASCs) and bone marrow-derived mesenchymal stem cells (Bm-MSCs) behave when cultured in specific pro-adipogenic microenvironments. The cells were first characterized and identified as MSCs in terms of their morphology, phenotypic expression, self-renewal capabilities and multi-lineage potential. Subsequently, the proliferation and gene expression profiles of the cell populations cultured on two-dimensional (2D) adipose tissue extracellular matrix (ECM)-coated tissue culture plastic (TCP) and in three-dimensional (3D) AlgiMatrix® microenvironments were analyzed. Overall, it was found that adipogenesis was triggered in both cell populations due to the presence of adipose tissue ECM. However, in 3D microenvironments, ASCs and Bm-MSCs were predisposed to the adipogenic and osteogenic lineages respectively. Overall, findings from this study will contribute to ongoing efforts in adipose tissue engineering as well as provide new insights into the role of the ECM and cues provided by the immediate microenvironment for stem cell differentiation. - Highlights: • Native adipose tissue ECM coated on 2D TCP triggers adipogenesis in both ASCs and Bm-MSCs. • A 3D microenvironment with similar stiffness to adipose tissue induces adipogenic differentiation of ASCs. • ASCs cultured in 3D alginate scaffolds exhibit predisposition to adipogenesis. • Bm-MSCs cultured in 3D alginate scaffolds exhibit predisposition to osteogenesis. • The native microenvironment of the cells affects their differentiation behaviour in vitro.

  14. Comparative study of adipose-derived stem cells and bone marrow-derived stem cells in similar microenvironmental conditions

    International Nuclear Information System (INIS)

    Guneta, Vipra; Tan, Nguan Soon; Chan, Soon Kiat Jeremy; Tanavde, Vivek; Lim, Thiam Chye; Wong, Thien Chong Marcus; Choong, Cleo

    2016-01-01

    Mesenchymal stem cells (MSCs), which were first isolated from the bone marrow, are now being extracted from various other tissues in the body, including the adipose tissue. The current study presents systematic evidence of how the adipose tissue-derived stem cells (ASCs) and bone marrow-derived mesenchymal stem cells (Bm-MSCs) behave when cultured in specific pro-adipogenic microenvironments. The cells were first characterized and identified as MSCs in terms of their morphology, phenotypic expression, self-renewal capabilities and multi-lineage potential. Subsequently, the proliferation and gene expression profiles of the cell populations cultured on two-dimensional (2D) adipose tissue extracellular matrix (ECM)-coated tissue culture plastic (TCP) and in three-dimensional (3D) AlgiMatrix® microenvironments were analyzed. Overall, it was found that adipogenesis was triggered in both cell populations due to the presence of adipose tissue ECM. However, in 3D microenvironments, ASCs and Bm-MSCs were predisposed to the adipogenic and osteogenic lineages respectively. Overall, findings from this study will contribute to ongoing efforts in adipose tissue engineering as well as provide new insights into the role of the ECM and cues provided by the immediate microenvironment for stem cell differentiation. - Highlights: • Native adipose tissue ECM coated on 2D TCP triggers adipogenesis in both ASCs and Bm-MSCs. • A 3D microenvironment with similar stiffness to adipose tissue induces adipogenic differentiation of ASCs. • ASCs cultured in 3D alginate scaffolds exhibit predisposition to adipogenesis. • Bm-MSCs cultured in 3D alginate scaffolds exhibit predisposition to osteogenesis. • The native microenvironment of the cells affects their differentiation behaviour in vitro.

  15. miRNA-720 controls stem cell phenotype, proliferation and differentiation of human dental pulp cells.

    Directory of Open Access Journals (Sweden)

    Emilio Satoshi Hara

    Full Text Available Dental pulp cells (DPCs are known to be enriched in stem/progenitor cells but not well characterized yet. Small non-coding microRNAs (miRNAs have been identified to control protein translation, mRNA stability and transcription, and have been reported to play important roles in stem cell biology, related to cell reprogramming, maintenance of stemness and regulation of cell differentiation. In order to characterize dental pulp stem/progenitor cells and its mechanism of differentiation, we herein sorted stem-cell-enriched side population (SP cells from human DPCs and periodontal ligament cells (PDLCs, and performed a locked nucleic acid (LNA-based miRNA array. As a result, miR-720 was highly expressed in the differentiated main population (MP cells compared to that in SP cells. In silico analysis and a reporter assay showed that miR-720 targets the stem cell marker NANOG, indicating that miR-720 could promote differentiation of dental pulp stem/progenitor cells by repressing NANOG. Indeed, gain-and loss-of-function analyses showed that miR-720 controls NANOG transcript and protein levels. Moreover, transfection of miR-720 significantly decreased the number of cells positive for the early stem cell marker SSEA-4. Concomitantly, mRNA levels of DNA methyltransferases (DNMTs, which are known to play crucial factors during stem cell differentiation, were also increased by miR-720 through unknown mechanism. Finally, miR-720 decreased DPC proliferation as determined by immunocytochemical analysis against ki-67, and promoted odontogenic differentiation as demonstrated by alizarin red staining, as well as alkaline phosphatase and osteopontin mRNA levels. Our findings identify miR-720 as a novel miRNA regulating the differentiation of DPCs.

  16. A basal stem cell signature identifies aggressive prostate cancer phenotypes

    Science.gov (United States)

    Smith, Bryan A.; Sokolov, Artem; Uzunangelov, Vladislav; Baertsch, Robert; Newton, Yulia; Graim, Kiley; Mathis, Colleen; Cheng, Donghui; Stuart, Joshua M.; Witte, Owen N.

    2015-01-01

    Evidence from numerous cancers suggests that increased aggressiveness is accompanied by up-regulation of signaling pathways and acquisition of properties common to stem cells. It is unclear if different subtypes of late-stage cancer vary in stemness properties and whether or not these subtypes are transcriptionally similar to normal tissue stem cells. We report a gene signature specific for human prostate basal cells that is differentially enriched in various phenotypes of late-stage metastatic prostate cancer. We FACS-purified and transcriptionally profiled basal and luminal epithelial populations from the benign and cancerous regions of primary human prostates. High-throughput RNA sequencing showed the basal population to be defined by genes associated with stem cell signaling programs and invasiveness. Application of a 91-gene basal signature to gene expression datasets from patients with organ-confined or hormone-refractory metastatic prostate cancer revealed that metastatic small cell neuroendocrine carcinoma was molecularly more stem-like than either metastatic adenocarcinoma or organ-confined adenocarcinoma. Bioinformatic analysis of the basal cell and two human small cell gene signatures identified a set of E2F target genes common between prostate small cell neuroendocrine carcinoma and primary prostate basal cells. Taken together, our data suggest that aggressive prostate cancer shares a conserved transcriptional program with normal adult prostate basal stem cells. PMID:26460041

  17. Roles of Mitochondrial DNA Mutations in Stem Cell Ageing

    Directory of Open Access Journals (Sweden)

    Tianhong Su

    2018-03-01

    Full Text Available Mitochondrial DNA (mtDNA mutations accumulate in somatic stem cells during ageing and cause mitochondrial dysfunction. In this review, we summarize the studies that link mtDNA mutations to stem cell ageing. We discuss the age-related behaviours of the somatic mtDNA mutations in stem cell populations and how they potentially contribute to stem cell ageing by altering mitochondrial properties in humans and in mtDNA-mutator mice. We also draw attention to the diverse fates of the mtDNA mutations with different origins during ageing, with potential selective pressures on the germline inherited but not the somatic mtDNA mutations.

  18. Stem Cells in Wound Healing: The Future of Regenerative Medicine? A Mini-Review.

    Science.gov (United States)

    Duscher, Dominik; Barrera, Janos; Wong, Victor W; Maan, Zeshaan N; Whittam, Alexander J; Januszyk, Michael; Gurtner, Geoffrey C

    2016-01-01

    The increased risk of disease and decreased capacity to respond to tissue insult in the setting of aging results from complex changes in homeostatic mechanisms, including the regulation of oxidative stress and cellular heterogeneity. In aged skin, the healing capacity is markedly diminished resulting in a high risk for chronic wounds. Stem cell-based therapies have the potential to enhance cutaneous regeneration, largely through trophic and paracrine activity. Candidate cell populations for therapeutic application include adult mesenchymal stem cells, embryonic stem cells and induced pluripotent stem cells. Autologous cell-based approaches are ideal to minimize immune rejection but may be limited by the declining cellular function associated with aging. One strategy to overcome age-related impairments in various stem cell populations is to identify and enrich with functionally superior stem cell subsets via single cell transcriptomics. Another approach is to optimize cell delivery to the harsh environment of aged wounds via scaffold-based cell applications to enhance engraftment and paracrine activity of therapeutic stem cells. In this review, we shed light on challenges and recent advances surrounding stem cell therapies for wound healing and discuss limitations for their clinical adoption. © 2015 S. Karger AG, Basel.

  19. Skeletal Muscle-derived Hematopoietic Stem Cells: Muscular Dystrophy Therapy by Bone Marrow Transplantation

    OpenAIRE

    Asakura, Atsushi

    2012-01-01

    For postnatal growth and regeneration of skeletal muscle, satellite cells, a self-renewing pool of muscle stem cells, give rise to daughter myogenic precursor cells that contribute to the formation of new muscle fibers. In addition to this key myogenic cell class, adult skeletal muscle also contains hematopoietic stem cell and progenitor cell populations which can be purified as a side population (SP) fraction or as a hematopoietic marker CD45-positive cell population. These muscle-derived he...

  20. CD71(high) population represents primitive erythroblasts derived from mouse embryonic stem cells.

    Science.gov (United States)

    Chao, Ruihua; Gong, Xueping; Wang, Libo; Wang, Pengxiang; Wang, Yuan

    2015-01-01

    The CD71/Ter119 combination has been widely used to reflect dynamic maturation of erythrocytes in vivo. However, because CD71 is expressed on all proliferating cells, it is unclear whether it can be utilized as an erythrocyte-specific marker during differentiation of embryonic stem cells (ESCs). In this study, we revealed that a population expressing high level of CD71 (CD71(high)) during mouse ESC differentiation represented an in vitro counterpart of yolk sac-derived primitive erythroblasts (EryPs) isolated at 8.5days post coitum. In addition, these CD71(high) cells went through "maturational globin switching" and enucleated during terminal differentiation in vitro that were similar to the yolk sac-derived EryPs in vivo. We further demonstrated that the formation of CD71(high) population was regulated differentially by key factors including Scl, HoxB4, Eaf1, and Klf1. Taken together, our study provides a technical advance that allows efficient segregation of EryPs from differentiated ESCs in vitro for further understanding molecular regulation during primitive erythropoiesis. Copyright © 2014. Published by Elsevier B.V.

  1. Cancer Stem-Like Cells Accumulated in Nickel-Induced Malignant Transformation

    Science.gov (United States)

    Wang, Lei; Fan, Jia; Hitron, John Andrew; Son, Young-Ok; Wise, James T.F.; Roy, Ram Vinod; Kim, Donghern; Dai, Jin; Pratheeshkumar, Poyil; Zhang, Zhuo; Shi, Xianglin

    2016-01-01

    Nickel compounds are known as human carcinogens. Chronic environmental exposure to nickel is a worldwide health concern. Although the mechanisms of nickel-induced carcinogenesis are not well understood, recent studies suggest that stem cells/cancer stem cells are likely important targets. This study examines the role of cancer stem cells in nickel-induced cell transformation. The nontransformed human bronchial epithelial cell line (Beas-2B) was chronically exposed to nickel chloride for 12 months to induce cell transformation. Nickel induced Beas-2B cell transformation, and cancer stem-like cells were enriched in nickel-transformed cell (BNiT) population. The BNiT cancer stem-like cells demonstrated enhanced self-renewal and distinctive differentiation properties. In vivo tumorigenesis studies show that BNiT cancer stem-like cells possess a high tumor-initiating capability. It was also demonstrated that superoxide dismutase 1 was involved in the accumulation of cancer stem-like cells; the regulation of superoxide dismutase 1 expression was different in transformed stem-like cells and nontransformed. Overall, the accumulation of stem-like cells and their enhanced stemness functions contribute to nickel-induced tumorigenesis. Our study provides additional insight into the mechanisms by which metals or other chemicals can induce carcinogenesis. PMID:26962057

  2. Biomarker screening of oral cancer cell lines revealed sub-populations of CD133-, CD44-, CD24- and ALDH1- positive cancer stem cells

    Directory of Open Access Journals (Sweden)

    Kendall K

    2013-05-01

    Full Text Available Head and neck squamous cell carcinoma (HNSCC ranks sixth worldwide for cancer-related mortality. For the past several decades the mainstay of treatment for HNSCC has been surgery and external beam radiation, although more recent trials combining chemotherapy and radiation have demonstrated improvements. However, cancer recurrence and treatment failures continue to occur in a significant percentage of patients. Recent advances in tumor biology have led to the discovery that many cancers, including HNSCC, may contain subpopulations of cells with stem cell-like properties that may explain relapse and recurrence. The objective of this study was to screen existing oral cancer cell lines for biomarkers specific for cells with stem cell-like properties. RNA was isolated for RT-PCR screening using primers for specific mRNA of the biomarkers: CD44, CD24, CD133, NANOG, Nestin, ALDH1, and ABCG2 in CAL27, SCC25 and SCC15 cells. This analysis revealed that some oral cancer cell lines (CAL27 and SCC25 may contain small subpopulations of adhesion- and contact-independent cells (AiDC that also express tumor stem cell markers, including CD44, CD133, and CD24. In addition, CAL27 cells also expressed the intracellular tumor stem cell markers, ALDH1 and ABCG2. Isolation and culture of the adhesion- and contact-independent cells from CAL27 and SCC25 populations revealed differential proliferation rates and more robust inhibition by the MEK inhibitor PD98059, as well as the chemotherapeutic agents Cisplatin and Paclitaxel, within the AiDC CAL27 cells. At least one oral cancer cell line (CAL27 contained subpopulations of cells that express specific biomarkers associated with tumor stem cells which were morphologically and phenotypically distinct from other cells within this cell line.

  3. Minichromosome maintenance helicase paralog MCM9 is dispensible for DNA replication but functions in germ-line stem cells and tumor suppression.

    Science.gov (United States)

    Hartford, Suzanne A; Luo, Yunhai; Southard, Teresa L; Min, Irene M; Lis, John T; Schimenti, John C

    2011-10-25

    Effective DNA replication is critical to the health and reproductive success of organisms. The six MCM2-7 proteins, which form the replicative helicase, are essential for high-fidelity replication of the genome. Many eukaryotes have a divergent paralog, MCM9, that was reported to be essential for loading MCM2-7 onto replication origins in the Xenopus oocyte extract system. To address the in vivo role of mammalian MCM9, we created and analyzed the phenotypes of mice with various mutations in Mcm9 and an intronic DNA replication-related gene Asf1a. Ablation of Mcm9 was compatible with cell proliferation and mouse viability, showing that it is nonessential for MCM2-7 loading or DNA replication. Mcm9 mutants underwent p53-independent embryonic germ-cell depletion in both sexes, with males also exhibiting defective spermatogonial stem-cell renewal. MCM9-deficient cells had elevated genomic instability and defective cell cycle reentry following replication stress, and mutant animals were prone to sex-specific cancers, most notably hepatocellular carcinoma in males. The phenotypes of mutant mice and cells suggest that MCM9 evolved a specialized but nonessential role in DNA replication or replication-linked quality-control mechanisms that are especially important for germ-line stem cells, and also for tumor suppression and genome maintenance in the soma.

  4. SCA-1 Expression Level Identifies Quiescent Hematopoietic Stem and Progenitor Cells

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    Mina N.F. Morcos

    2017-06-01

    Full Text Available Blood cell generation depends on continuous cellular output by the sequential hierarchy of hematopoietic stem cell (HSC and progenitor populations that all contain quiescent and actively cycling cells. Hematopoietic stem and progenitor cells (HSPCs express the surface molecule Stem cell antigen 1 (SCA-1/LY6A. Using histone 2B-red fluorescent fusion protein label retention and cell-cycle reporter mice, we demonstrate that high SCA-1 expression (SCA-1hi identifies not only quiescent HSCs but quiescent cells on all hierarchical levels within the lineage−SCA-1+KIT+ (LSK population. Each transplanted SCA-1hi HSPC population also displayed self-renewal potential superior to that of the respective SCA-1lo population. SCA-1 expression is inducible by type I interferon (IFN. We show, however, that quiescence and high self-renewal capacity of cells with brighter SCA-1 expression at steady state were independent of type I IFN signaling. We conclude that SCA-1 expression levels can be used to prospectively isolate functionally heterogeneous HSPC subpopulations.

  5. In search of better spermatogonial preservation by supplementation of cryopreserved human immature testicular tissue xenografts with N-acetylcysteine and testosterone

    Directory of Open Access Journals (Sweden)

    Jonathan ePoels

    2014-12-01

    Full Text Available Controlled slow-freezing is the procedure currently applied for immature testicular tissue cryobanking in clinical practice. Vitrification has been proposed as a promising alternative, with a view to better preserving spermatogonial stem cells for future fertility restoration by autografting in young boys suffering from cancer. It appears that besides the potential influence of the cryopreservation technique used, the transplantation procedure itself has a significant impact on spermatogonial loss observed in ITT xenografts. Eighteen immature testicular tissue pieces issuing from 6 patients aged 2-15 years were used. Fragments of fresh tissue (serving as ungrafted controls, frozen-thawed tissue, frozen-thawed tissue supplemented with N-acetylcysteine and frozen-thawed tissue supplemented with testosterone xenografted to nude mice for 5 days were compared. Upon graft removal, histological and immunohistochemical analyses were performed to evaluate spermatogonia, intratubular proliferation and intrinsic and extrinsic apoptosis. A significant decrease in the integrity of intact seminiferous tubules was found in all three grafted groups. Spermatogonia were observed by immunohistochemistry in all grafted groups, with recovery rates of 67%, 63% and 53% respectively for slow-frozen tissue, slow-frozen tissue supplemented with N-acetylcysteine and slow-frozen tissue supplemented with testosterone. Apoptosis evidenced by active caspase-3 and TUNEL was similar in all grafts. The study is limited by the low availability of immature testicular tissue samples of human origin, and no clear impact of graft supplementation was found. The mouse xenotransplantation model needs to be refined to investigate human spermatogenesis in human immature testicular tissue grafts.

  6. HLA engineering of human pluripotent stem cells.

    Science.gov (United States)

    Riolobos, Laura; Hirata, Roli K; Turtle, Cameron J; Wang, Pei-Rong; Gornalusse, German G; Zavajlevski, Maja; Riddell, Stanley R; Russell, David W

    2013-06-01

    The clinical use of human pluripotent stem cells and their derivatives is limited by the rejection of transplanted cells due to differences in their human leukocyte antigen (HLA) genes. This has led to the proposed use of histocompatible, patient-specific stem cells; however, the preparation of many different stem cell lines for clinical use is a daunting task. Here, we develop two distinct genetic engineering approaches that address this problem. First, we use a combination of gene targeting and mitotic recombination to derive HLA-homozygous embryonic stem cell (ESC) subclones from an HLA-heterozygous parental line. A small bank of HLA-homozygous stem cells with common haplotypes would match a significant proportion of the population. Second, we derive HLA class I-negative cells by targeted disruption of both alleles of the Beta-2 Microglobulin (B2M) gene in ESCs. Mixed leukocyte reactions and peptide-specific HLA-restricted CD8(+) T cell responses were reduced in class I-negative cells that had undergone differentiation in embryoid bodies. These B2M(-/-) ESCs could act as universal donor cells in applications where the transplanted cells do not express HLA class II genes. Both approaches used adeno-associated virus (AAV) vectors for efficient gene targeting in the absence of potentially genotoxic nucleases, and produced pluripotent, transgene-free cell lines.

  7. HLA Engineering of Human Pluripotent Stem Cells

    Science.gov (United States)

    Riolobos, Laura; Hirata, Roli K; Turtle, Cameron J; Wang, Pei-Rong; Gornalusse, German G; Zavajlevski, Maja; Riddell, Stanley R; Russell, David W

    2013-01-01

    The clinical use of human pluripotent stem cells and their derivatives is limited by the rejection of transplanted cells due to differences in their human leukocyte antigen (HLA) genes. This has led to the proposed use of histocompatible, patient-specific stem cells; however, the preparation of many different stem cell lines for clinical use is a daunting task. Here, we develop two distinct genetic engineering approaches that address this problem. First, we use a combination of gene targeting and mitotic recombination to derive HLA-homozygous embryonic stem cell (ESC) subclones from an HLA-heterozygous parental line. A small bank of HLA-homozygous stem cells with common haplotypes would match a significant proportion of the population. Second, we derive HLA class I–negative cells by targeted disruption of both alleles of the Beta-2 Microglobulin (B2M) gene in ESCs. Mixed leukocyte reactions and peptide-specific HLA-restricted CD8+ T cell responses were reduced in class I–negative cells that had undergone differentiation in embryoid bodies. These B2M−/− ESCs could act as universal donor cells in applications where the transplanted cells do not express HLA class II genes. Both approaches used adeno-associated virus (AAV) vectors for efficient gene targeting in the absence of potentially genotoxic nucleases, and produced pluripotent, transgene-free cell lines. PMID:23629003

  8. Advancing Stem Cell Biology toward Stem Cell Therapeutics

    OpenAIRE

    Scadden, David; Srivastava, Alok

    2012-01-01

    Here, the International Society for Stem Cell Research (ISSCR) Clinical Translation Committee introduces a series of articles outlining the current status, opportunities, and challenges surrounding the clinical translation of stem cell therapeutics for specific medical conditions.

  9. Berberine diminishes side population and down-regulates stem cell-associated genes in the pancreatic cancer cell lines PANC-1 and MIA PaCa-2.

    Science.gov (United States)

    Park, S H; Sung, J H; Chung, N

    2014-09-01

    Cancer stem cells play an important role in metastasis and the relapse of drug resistant cancers. Side-population (SP) cells are capable of effluxing Hoechst 33342 dye and are referred to as cancer stem cells. We investigated the effect of berberine on pancreatic cancer stem cells of PANC-1 and MIA PaCa-2. For both cell lines, the proportions of SP cells in the presence of berberine were investigated and compared to the proportions in the presence of gemcitabine, a standard pancreatic anti-cancer drug. The proportions of SP cells in the PANC-1 and MIA PaCa-2 cell lines were about 9 and PANC-1 decreased to 5.7 ± 2.0 and 6.8 ± 0.8%, respectively, which compares to the control proportion of (9.7 ± 1.7). After berberine and gemcitabine treatment of PANC-1, of the four stem cell-associated genes (SOX2, POU5F1, NANOG, and NOTCH1), all but NOTCH1 were down-regulated. Unfortunately, the effect of berberine and gemcitabine treatments on MIA PaCa-2 SP cells could not be clearly observed because SP cells represented only a very small proportion of MIA PaCa-2 cells. However, SOX2, POU5F1, and NANOG genes were shown to be effectively down-regulated in the MIA PaCa-2 cell line as a whole. Taken together, these results indicate that berberine is as effective at targeting pancreatic cancer cell lines as gemcitabine. Therefore, we believe that POU5F1, SOX2, and NANOG can serve as potential markers, and berberine may be an effective anti-cancer agent when targeting human pancreatic cancer cells and/or their cancer stem cells.

  10. The Evolution of the Stem Cell Theory for Heart Failure.

    Science.gov (United States)

    Silvestre, Jean-Sébastien; Menasché, Philippe

    2015-12-01

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

  11. The Evolution of the Stem Cell Theory for Heart Failure

    Directory of Open Access Journals (Sweden)

    Jean-Sébastien Silvestre

    2015-12-01

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

  12. Fetal bovine serum simultaneously stimulates apoptosis and DNA synthesis in premeiotic stages of spermatogenesis in spiny dogfish (Squalus acanthias) in vitro: modulation by androgen and spermatogenic activity status.

    Science.gov (United States)

    McClusky, Leon Mendel

    2008-05-01

    Using the simple cystic spermatogenesis in the shark testis as a model, we previously reported the relative resistance of immature spermatogonia (stem cell and early-stage spermatogonia) to apoptosis in the normal testis and after spermatoxicant exposure in vivo. Apoptosis was monitored by fluorescence image analysis of living cysts, using the validated acridine orange (AO) vital staining technique. Findings show that FBS simultaneously stimulates both apoptosis and [(3)H]thymidine incorporation in immature spermatogonial clones in a concentration-dependent manner in vitro. Furthermore, androgen inhibits apoptosis and increases cyst viability, more so with 10% FBS than with 1% FBS. All the effects were as a function of spermatogenic activity status but were distinct in early-stage spermatogonial cysts isolated from testes awakening from the previous winter spermatogenic arrest period. Results are discussed in the context of the alternating germ-Sertoli cell population kinetics of early-stage spermatogonial cysts in Squalus acanthias's protracted testicular cycle.

  13. Role of bone marrow-derived stem cells, renal progenitor cells and stem cell factor in chronic renal allograft nephropathy

    Directory of Open Access Journals (Sweden)

    Hayam Abdel Meguid El Aggan

    2013-09-01

    Full Text Available Introduction: Chronic allograft nephropathy (CAN is a poorly understood clinico-pathological entity associated with chronic allograft loss due to immunologic and non-immunologic causes. It remains the leading cause of late allograft loss. Bone marrow derived stem cells are undifferentiated cells typically characterized by their capacity for self renewal, ability to give rise to multiple differentiated cellular population, including hematopoietic (HSCs and mesenchymal stem cells (MSCs. Characterization of HSCs includes their multipotency, expression of typical surface markers such as CD34 and CD45, while characterization of MSC includes their multipotency, expression of typical surface markers such as CD90 and CD105, and the absence of hemopoietic lineage markers. Aim & methods: The aim of the present work was to study the role of bone marrow-derived HSCs and MSCs, renal progenitor cells and SCF in chronic renal allograft nephropathy in relation to renal hemodynamics and histopathological changes. We studied 30 patients with kidney transplantation for more than 6 months, divided into 15 patients with stable serum creatinine and 15 patients who developed CAN. Detection of HSCs and MSCs in the peripheral blood using flow cytometry via detection of CD34, CD45, CD117 and CD106, as well as immunohistochemical detection of CD34, CD133, VEGF and αSMA in transplanted kidney biopsies of patients with CAN were done. Results: There was a significant increase in the levels of SCF, number of peripheral blood HSCs and MSCs in both transplanted patient groups than the controls and they were higher in patients of group Ia than patients of group Ib, (F = 39.73, P < 0.001, (F = 13.28, P < 0.001, (F = 11.94, P < 0.001, respectively and this was accompanied by evident expression of markers of renal repair. Conclusion: Stem cells might have a role in renal regeneration in CAN and this may pave the way toward the use of stem cells in correction of CAN. KEYWORDS

  14. Regenerative Endodontics in light of the stem cell paradigm

    Science.gov (United States)

    Rosa, Vinicius; Botero, Tatiana M.; Nör, Jacques E.

    2013-01-01

    Stem cells play a critical role in development and in tissue regeneration. The dental pulp contains a small sub-population of stem cells that are involved in the response of the pulp to caries progression. Specifically, stem cells replace odontoblasts that have undergone cell death as a consequence of the cariogenic challenge. Stem cells also secrete factors that have the potential to enhance pulp vascularization and provide the oxygen and nutrients required for the dentinogenic response that is typically observed in teeth with deep caries. However, the same angiogenic factors that are required for dentin regeneration may ultimately contribute to the demise of the pulp by enhancing vascular permeability and interstitial pressure. Recent studies focused on the biology of dental pulp stem cells revealed that the multipotency and angiogenic capacity of these cells could be exploited therapeutically in dental pulp tissue engineering. Collectively, these findings suggest new treatment paradigms in the field of Endodontics. The goal of this review is to discuss the potential impact of dental pulp stem cells to Regenerative Endodontics. PMID:21726222

  15. SILAC Proteomics of Planarians Identifies Ncoa5 as a Conserved Component of Pluripotent Stem Cells

    Directory of Open Access Journals (Sweden)

    Alexander Böser

    2013-11-01

    Full Text Available 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.

  16. NKX6.1 induced pluripotent stem cell reporter lines for isolation and analysis of functionally relevant neuronal and pancreas populations

    Directory of Open Access Journals (Sweden)

    Shailesh Kumar Gupta

    2018-05-01

    Full Text Available Recent studies have reported significant advances in the differentiation of human pluripotent stem cells to clinically relevant cell types such as the insulin producing beta-like cells and motor neurons. However, many of the current differentiation protocols lead to heterogeneous cell cultures containing cell types other than the targeted cell fate. Genetically modified human pluripotent stem cells reporting the expression of specific genes are of great value for differentiation protocol optimization and for the purification of relevant cell populations from heterogeneous cell cultures. Here we present the generation of human induced pluripotent stem cell (iPSC lines with a GFP reporter inserted in the endogenous NKX6.1 locus. Characterization of the reporter lines demonstrated faithful GFP labelling of NKX6.1 expression during pancreas and motor neuron differentiation. Cell sorting and gene expression profiling by RNA sequencing revealed that NKX6.1-positive cells from pancreatic differentiations closely resemble human beta cells. Furthermore, functional characterization of the isolated cells demonstrated that glucose-stimulated insulin secretion is mainly confined to the NKX6.1-positive cells. We expect that the NKX6.1-GFP iPSC lines and the results presented here will contribute to the further refinement of differentiation protocols and characterization of hPSC-derived beta cells and motor neurons for disease modelling and cell replacement therapies. Keywords: Human induced pluripotent stem cells, NKX6.1, Reporter cell line, Directed differentiation, hiPSC-derived beta cells

  17. [Cancer stem cells as the therapeutic target of tomorrow].

    Science.gov (United States)

    Hatina, Jiří

    2017-02-01

    The concept of hierarchical organization of tumour cell population, with cancer stem cells positioned at the apex of the cell hierarchy, can explain at least some crucial aspects of biological and clinical behaviour of cancer, like its propensity to relapse as well as the development of therapeutic resistance. The underlying biological properties of cancer stem cells are crucially dependent on various signals, inhibition of which provides an attractive opportunity to attack pharmacologically cancer stem cells. Currently, a lot of such stemness-inhibitors undergo various phases of clinical testing. Interestingly, numerous old drugs that are in routine use in human and veterinary medicine for non-oncological indications appear to be able to specifically target cancer stem cells as well. As cancer stem cells, at least for most tumours, represent usually only a minor tumour cell fraction, it is quite probable that the main focus of the clinical use of the stemness inhibitors would consist in their rational combinations with traditional anticancer treatment modalities. A highly important goal for the future research is to identify reliable and clinically applicable predictive markers that would allow to apply these novel anticancer drugs on the individual basis within the context of personalized medicine.

  18. Stem cell markers in the heart of the human newborn

    Directory of Open Access Journals (Sweden)

    Armando Faa

    2016-07-01

    Full Text Available The identification of cardiac progenitor cells in mammals raises the possibility that the human heart contains a population of stem cells capable of generating cardiomyocytes and coronary vessels. Several recent studies now show that the different cell types that characterize the adult human heart arise from a common ancestor. Human cardiac stem cells differentiate into cardiomyocytes, and, in lesser extent, into smooth muscle and endothelial cells. The characterization of human cardiac stem cells (CSCs has important clinical implications. In recent years, CD117 (c-kit has been reported to mark a subtype of stem/progenitor cells in the human heart, with stem cell-like properties, including the ability to self-renewal and clonogenicity multipotentiality. Proceedings of the 2nd International Course on Perinatal Pathology (part of the 11th International Workshop on Neonatology · October 26th-31st, 2015 · Cagliari (Italy · October 31st, 2015 · Stem cells: present and future Guest Editors: Gavino Faa, Vassilios Fanos, Antonio Giordano

  19. Stem cells engineering for cell-based therapy.

    Science.gov (United States)

    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.

  20. Potency of Stem Cells

    Indian Academy of Sciences (India)

    First page Back Continue Last page Overview Graphics. Potency of Stem Cells. Totipotent Stem Cells (Zygote + first 2 divisions). -Can form placenta, embryo, and any cell of the body. Pluripotent (Embryonic Stem Cells). -Can form any cell of the body but can not form placenta, hence no embryo. Multipotent (Adult stem cells).

  1. Proteomic cornerstones of hematopoietic stem cell differentiation

    DEFF Research Database (Denmark)

    Klimmeck, Daniel; Hansson, Jenny; Raffel, Simon

    2012-01-01

    Regenerative tissues such as the skin epidermis, the intestinal mucosa or the hematopoietic system are organized in a hierarchical manner with stem cells building the top of this hierarchy. Somatic stem cells harbor the highest self-renewal activity and generate a series of multipotent progenitors...... which differentiate into lineage committed progenitors and subsequently mature cells. In this report, we applied an in-depth quantitative proteomic approach to analyze and compare the full proteomes of ex vivo isolated and FACS-sorted populations highly enriched for either multipotent hematopoietic stem....../progenitor cells (HSPCs, Lin(neg)Sca-1(+)c-Kit(+)) or myeloid committed precursors (Lin(neg)Sca-1(-)c-Kit(+)). By employing stable isotope dimethyl labeling and high-resolution mass spectrometry, more than 5,000 proteins were quantified. From biological triplicate experiments subjected to rigorous statistical...

  2. Calvarial Suture-Derived Stem Cells and Their Contribution to Cranial Bone Repair

    Directory of Open Access Journals (Sweden)

    Daniel H. Doro

    2017-11-01

    Full Text Available In addition to the natural turnover during life, the bones in the skeleton possess the ability to self-repair in response to injury or disease-related bone loss. Based on studies of bone defect models, both processes are largely supported by resident stem cells. In the long bones, the source of skeletal stem cells has been widely investigated over the years, where the major stem cell population is thought to reside in the perivascular niche of the bone marrow. In contrast, we have very limited knowledge about the stem cells contributing to the repair of calvarial bones. In fact, until recently, the presence of specific stem cells in adult craniofacial bones was uncertain. These flat bones are mainly formed via intramembranous rather than endochondral ossification and thus contain minimal bone marrow space. It has been previously proposed that the overlying periosteum and underlying dura mater provide osteoprogenitors for calvarial bone repair. Nonetheless, recent studies have identified a major stem cell population within the suture mesenchyme with multiple differentiation abilities and intrinsic reparative potential. Here we provide an updated review of calvarial stem cells and potential mechanisms of regulation in the context of skull injury repair.

  3. An Update on Ocular Surface Epithelial Stem Cells: Cornea and Conjunctiva

    Directory of Open Access Journals (Sweden)

    Tiago Ramos

    2015-01-01

    Full Text Available The human ocular surface (front surface of the eye is formed by two different types of epithelia: the corneal epithelium centrally and the conjunctival epithelium that surrounds this. These two epithelia are maintained by different stem cell populations (limbal stem cells for the corneal epithelium and the conjunctival epithelial stem cells. In this review, we provide an update on our understanding of these epithelia and their stem cells systems, including embryology, new markers, and controversy around the location of these stem cells. We also provide an update on the translation of this understanding into clinical applications for the treatment of debilitating ocular surface diseases.

  4. Vitamin A/Retinol and Maintenance of Pluripotency of Stem Cells

    Directory of Open Access Journals (Sweden)

    Jaspal S. Khillan

    2014-03-01

    Full Text Available Retinol, the alcohol form of vitamin A is a key dietary component that plays a critical role in vertebrate development, cell differentiation, reproduction, vision and immune system. Natural and synthetic analogs of retinol, called retinoids, have generally been associated with the cell differentiation via retinoic acid which is the most potent metabolite of retinol. However, a direct function of retinol has not been fully investigated. New evidence has now emerged that retinol supports the self-renewal of stem cells including embryonic stem cells (ESCs, germ line stem cells (GSCs and cancer stem cells (CSCs by activating the endogenous machinery for self-renewal by a retinoic acid independent mechanism. The studies have also revealed that stem cells do not contain enzymes that are responsible for metabolizing retinol into retinoic acid. This new function of retinol may have important implications for stem cell biology which can be exploited for quantitative production of pure population of pluripotent stem cells for regenerative medicine as well as clinical applications for cancer therapeutics.

  5. Pulp tissue from primary teeth: new source of stem cells

    Directory of Open Access Journals (Sweden)

    Paloma Dias Telles

    2011-06-01

    Full Text Available SHED (stem cells from human exfoliated deciduous teeth represent a population of postnatal stem cells capable of extensive proliferation and multipotential differentiation. Primary teeth may be an ideal source of postnatal stem cells to regenerate tooth structures and bone, and possibly to treat neural tissue injury or degenerative diseases. SHED are highly proliferative cells derived from an accessible tissue source, and therefore hold potential for providing enough cells for clinical applications. In this review, we describe the current knowledge about dental pulp stem cells and discuss tissue engineering approaches that use SHED to replace irreversibly inflamed or necrotic pulps with a healthy and functionally competent tissue that is capable of forming new dentin.

  6. Retinal stem cells and potential cell transplantation treatments

    Directory of Open Access Journals (Sweden)

    Tai-Chi Lin

    2014-11-01

    Full Text Available The retina, histologically composed of ten delicate layers, is responsible for light perception and relaying electrochemical signals to the secondary neurons and visual cortex. Retinal disease is one of the leading clinical causes of severe vision loss, including age-related macular degeneration, Stargardt's disease, and retinitis pigmentosa. As a result of the discovery of various somatic stem cells, advances in exploring the identities of embryonic stem cells, and the development of induced pluripotent stem cells, cell transplantation treatment for retinal diseases is currently attracting much attention. The sources of stem cells for retinal regeneration include endogenous retinal stem cells (e.g., neuronal stem cells, Müller cells, and retinal stem cells from the ciliary marginal zone and exogenous stem cells (e.g., bone mesenchymal stem cells, adipose-derived stem cells, embryonic stem cells, and induced pluripotent stem cells. The success of cell transplantation treatment depends mainly on the cell source, the timing of cell harvesting, the protocol of cell induction/transplantation, and the microenvironment of the recipient's retina. This review summarizes the different sources of stem cells for regeneration treatment in retinal diseases and surveys the more recent achievements in animal studies and clinical trials. Future directions and challenges in stem cell transplantation are also discussed.

  7. Neural crest stem cell population in craniomaxillofacial development and tissue repair

    Directory of Open Access Journals (Sweden)

    M La Noce

    2014-10-01

    Full Text Available Neural crest cells, delaminating from the neural tube during migration, undergo an epithelial-mesenchymal transition and differentiate into several cell types strongly reinforcing the mesoderm of the craniofacial body area – giving rise to bone, cartilage and other tissues and cells of this human body area. Recent studies on craniomaxillofacial neural crest-derived cells have provided evidence for the tremendous plasticity of these cells. Actually, neural crest cells can respond and adapt to the environment in which they migrate and the cranial mesoderm plays an important role toward patterning the identity of the migrating neural crest cells. In our experience, neural crest-derived stem cells, such as dental pulp stem cells, can actively proliferate, repair bone and give rise to other tissues and cytotypes, including blood vessels, smooth muscle, adipocytes and melanocytes, highlighting that their use in tissue engineering is successful. In this review, we provide an overview of the main pathways involved in neural crest formation, delamination, migration and differentiation; and, in particular, we concentrate our attention on the translatability of the latest scientific progress. Here we try to suggest new ideas and strategies that are needed to fully develop the clinical use of these cells. This effort should involve both researchers/clinicians and improvements in good manufacturing practice procedures. It is important to address studies towards clinical application or take into consideration that studies must have an effective therapeutic prospect for humans. New approaches and ideas must be concentrated also toward stem cell recruitment and activation within the human body, overcoming the classical grafting.

  8. STEM CELL ORIGIN DIFFERENTLY AFFECTS BONE TISSUE ENGINEERING STRATEGIES.

    Directory of Open Access Journals (Sweden)

    Monica eMattioli-Belmonte

    2015-09-01

    Full Text Available Bone tissue engineering is a promising research area for the improvement of traditional bone grafting procedure drawbacks. Thanks to the capability of self-renewal and multi-lineage differentiation, stem cells are one of the major actors in tissue engineering approaches, and adult mesenchymal stem cells (MSCs are considered to be appropriate for regenerative medicine strategies. Bone marrow MSCs (BM-MSCs are the earliest- discovered and well-known stem cell population used in bone tissue engineering. However, several factors hamper BM-MSC clinical application and subsequently, new stem cell sources have been investigated for these purposes. The successful identification and combination of tissue engineering, scaffold, progenitor cells, and physiologic signalling molecules enabled the surgeon to design, recreate the missing tissue in its near natural form. On the basis of these considerations, we analysed the capability of two different scaffolds, planned for osteochondral tissue regeneration, to modulate differentiation of adult stem cells of dissimilar local sources (i.e. periodontal ligament, maxillary periosteum as well as adipose-derived stem cells, in view of possible craniofacial tissue engineering strategies. We demonstrated that cells are differently committed toward the osteoblastic phenotype and therefore, considering their peculiar features, they may alternatively represent interesting cell sources in different stem cell-based bone/periodontal tissue regeneration approaches.

  9. Phenotypic characterization of aberrant stem and progenitor cell populations in myelodysplastic syndromes.

    Science.gov (United States)

    Ostendorf, Benjamin N; Flenner, Eva; Flörcken, Anne; Westermann, Jörg

    2018-01-01

    Recent reports have revealed myelodysplastic syndromes (MDS) to arise from cancer stem cells phenotypically similar to physiological hematopoietic stem cells. Myelodysplastic hematopoiesis maintains a hierarchical organization, but the proportion of several hematopoietic compartments is skewed and multiple surface markers are aberrantly expressed. These aberrant antigen expression patterns hold diagnostic and therapeutic promise. However, eradication of MDS requires targeting of early myelodysplasia propagating stem cells. This warrants an exact assessment of the differentiation stage at which aberrant expression occurs in transformed hematopoiesis. Here, we report results on the prospective and extensive dissection of the hematopoietic hierarchy in 20 patients with either low-risk MDS or MDS with excess blasts and compare it to hematopoiesis in patients with non-malignancy-associated cytopenia or B cell lymphoma without bone marrow infiltration. We found patients with MDS with excess blasts to exhibit characteristic expansions of specific immature progenitor compartments. We also identified the aberrant expression of several markers including ALDH, CLL-1, CD44, and CD47 to be specific features of hematopoiesis in MDS with excess blasts. We show that amongst these, aberrant CLL-1 expression manifested at the early uncommitted hematopoietic stem cell level, suggesting a potential role as a therapeutic target.

  10. Phenotypic characterization of aberrant stem and progenitor cell populations in myelodysplastic syndromes.

    Directory of Open Access Journals (Sweden)

    Benjamin N Ostendorf

    Full Text Available Recent reports have revealed myelodysplastic syndromes (MDS to arise from cancer stem cells phenotypically similar to physiological hematopoietic stem cells. Myelodysplastic hematopoiesis maintains a hierarchical organization, but the proportion of several hematopoietic compartments is skewed and multiple surface markers are aberrantly expressed. These aberrant antigen expression patterns hold diagnostic and therapeutic promise. However, eradication of MDS requires targeting of early myelodysplasia propagating stem cells. This warrants an exact assessment of the differentiation stage at which aberrant expression occurs in transformed hematopoiesis. Here, we report results on the prospective and extensive dissection of the hematopoietic hierarchy in 20 patients with either low-risk MDS or MDS with excess blasts and compare it to hematopoiesis in patients with non-malignancy-associated cytopenia or B cell lymphoma without bone marrow infiltration. We found patients with MDS with excess blasts to exhibit characteristic expansions of specific immature progenitor compartments. We also identified the aberrant expression of several markers including ALDH, CLL-1, CD44, and CD47 to be specific features of hematopoiesis in MDS with excess blasts. We show that amongst these, aberrant CLL-1 expression manifested at the early uncommitted hematopoietic stem cell level, suggesting a potential role as a therapeutic target.

  11. Castration-Resistant Lgr5+ Cells Are Long-Lived Stem Cells Required for Prostatic Regeneration

    Directory of Open Access Journals (Sweden)

    Bu-er Wang

    2015-05-01

    Full Text Available The adult prostate possesses a significant regenerative capacity that is of great interest for understanding adult stem cell biology. We demonstrate that leucine-rich repeat-containing G protein-coupled receptor 5 (Lgr5 is expressed in a rare population of prostate epithelial progenitor cells, and a castration-resistant Lgr5+ population exists in regressed prostate tissue. Genetic lineage tracing revealed that Lgr5+ cells and their progeny are primarily luminal. Lgr5+ castration-resistant cells are long lived and upon regeneration, both luminal Lgr5+ cells and basal Lgr5+ cells expand. Moreover, single Lgr5+ cells can generate multilineage prostatic structures in renal transplantation assays. Additionally, Lgr5+ cell depletion revealed that the regenerative potential of the castrated adult prostate depends on Lgr5+ cells. Together, these data reveal insights into the cellular hierarchy of castration-resistant Lgr5+ cells, indicate a requirement for Lgr5+ cells during prostatic regeneration, and identify an Lgr5+ adult stem cell population in the prostate.

  12. Isolation and Characterization of Cancer Stem Cells of the Non-Small-Cell Lung Cancer (A549) Cell Line.

    Science.gov (United States)

    Halim, Noor Hanis Abu; Zakaria, Norashikin; Satar, Nazilah Abdul; Yahaya, Badrul Hisham

    2016-01-01

    Cancer is a major health problem worldwide. The failure of current treatments to completely eradicate cancer cells often leads to cancer recurrence and dissemination. Studies have suggested that tumor growth and spread are driven by a minority of cancer cells that exhibit characteristics similar to those of normal stem cells, thus these cells are called cancer stem cells (CSCs). CSCs are believed to play an important role in initiating and promoting cancer. CSCs are resistant to currently available cancer therapies, and understanding the mechanisms that control the growth of CSCs might have great implications for cancer therapy. Cancer cells are consist of heterogeneous population of cells, thus methods of identification, isolation, and characterisation of CSCs are fundamental to obtain a pure CSC populations. Therefore, this chapter describes in detail a method for isolating and characterizing a pure population of CSCs from heterogeneous population of cancer cells and CSCs based on specific cell surface markers.

  13. Hair Follicle: A Novel Source of Multipotent Stem Cells for Tissue Engineering and Regenerative Medicine

    Science.gov (United States)

    Mistriotis, Panagiotis

    2013-01-01

    The adult body harbors powerful reservoirs of stem cells that enable tissue regeneration under homeostatic conditions or in response to disease or injury. The hair follicle (HF) is a readily accessible mini organ within the skin and contains stem cells from diverse developmental origins that were shown to have surprisingly broad differentiation potential. In this review, we discuss the biology of the HF with particular emphasis on the various stem cell populations residing within the tissue. We summarize the existing knowledge on putative HF stem cell markers, the differentiation potential, and technologies to isolate and expand distinct stem cell populations. We also discuss the potential of HF stem cells for drug and gene delivery, tissue engineering, and regenerative medicine. We propose that the abundance of stem cells with broad differentiation potential and the ease of accessibility makes the HF an ideal source of stem cells for gene and cell therapies. PMID:23157470

  14. Induced adult stem (iAS) cells and induced transit amplifying progenitor (iTAP) cells-a possible alternative to induced pluripotent stem (iPS) cells?

    Science.gov (United States)

    Heng, Boon Chin; Richards, Mark; Ge, Zigang; Shu, Yimin

    2010-02-01

    The successful derivation of iPSC lines effectively demonstrates that it is possible to reset the 'developmental clock' of somatic cells all the way back to the initial embryonic state. Hence, it is plausible that this clock may instead be turned back half-way to a less immature developmental stage that is more directly applicable to clinical therapeutic applications or for in vitro pharmacology/toxicology screening assays. Such a suitable developmental state is postulated to be either the putative transit amplifying progenitor stage or adult stem cell stage. It is hypothetically possible to reprogram mature and terminally differentiated somatic cells back to the adult stem cell or transit amplifying progenitor stage, in a manner similar to the derivation of iPSC. It is proposed that the terminology 'Induced Adult Stem Cells' (iASC) or 'Induced Transit Amplifying Progenitor Cells' (iTAPC) be used to described such reprogrammed somatic cells. Of particular interest, is the possibility of resetting the developmental clock of mature differentiated somatic cells of the mesenchymal lineage, explanted from adipose tissue, bone marrow and cartilage. The putative adult stem cell sub-population from which these cells are derived, commonly referred to as 'mesenchymal stem cells', are highly versatile and hold much therapeutic promise in regenerative medicine, as attested to by numerous human clinical trials and animal studies. Perhaps it may be appropriate to term such reprogrammed cells as 'Induced Mesenchymal Stem Cells' (iMSC) or as 'Induced Mesenchumal Progenitor Cells' (iMPC). Given that cells from the same organ/tissue will share some commonalities in gene expression, we hypothesize that the generation of iASC or iTAPC would be more efficient as compared to iPSC generation, since a common epigenetic program must exist between the reprogrammed cells, adult stem cell or progenitor cell types and terminally differentiated cell types from the same organ/tissue.

  15. Generation of folliculogenic human epithelial stem cells from induced pluripotent stem cells

    Science.gov (United States)

    Yang, Ruifeng; Zheng, Ying; Burrows, Michelle; Liu, Shujing; Wei, Zhi; Nace, Arben; Guo, Wei; Kumar, Suresh; Cotsarelis, George; Xu, Xiaowei

    2014-01-01

    Epithelial stem cells (EpSCs) in the hair follicle bulge are required for hair follicle growth and cycling. The isolation and propagation of human EpSCs for tissue engineering purposes remains a challenge. Here we develop a strategy to differentiate human iPSCs (hiPSCs) into CD200+/ITGA6+ EpSCs that can reconstitute the epithelial components of the hair follicle and interfollicular epidermis. The hiPSC-derived CD200+/ITGA6+ cells show a similar gene expression signature as EpSCs directly isolated from human hair follicles. Human iPSC-derived CD200+/ITGA6+ cells are capable of generating all hair follicle lineages including the hair shaft, and the inner and outer root sheaths in skin reconstitution assays. The regenerated hair follicles possess a KRT15+ stem cell population and produce hair shafts expressing hair-specific keratins. These results suggest an approach for generating large numbers of human EpSCs for tissue engineering and new treatments for hair loss, wound healing and other degenerative skin disorders.

  16. The promises of stem cells: stem cell therapy for movement disorders.

    Science.gov (United States)

    Mochizuki, Hideki; Choong, Chi-Jing; Yasuda, Toru

    2014-01-01

    Despite the multitude of intensive research, the exact pathophysiological mechanisms underlying movement disorders including Parkinson's disease, multiple system atrophy and Huntington's disease remain more or less elusive. Treatments to halt these disease progressions are currently unavailable. With the recent induced pluripotent stem cells breakthrough and accomplishment, stem cell research, as the vast majority of scientists agree, holds great promise for relieving and treating debilitating movement disorders. As stem cells are the precursors of all cells in the human body, an understanding of the molecular mechanisms that govern how they develop and work would provide us many fundamental insights into human biology of health and disease. Moreover, stem-cell-derived neurons may be a renewable source of replacement cells for damaged neurons in movement disorders. While stem cells show potential for regenerative medicine, their use as tools for research and drug testing is thought to have more immediate impact. The use of stem-cell-based drug screening technology could be a big boost in drug discovery for these movement disorders. Particular attention should also be given to the involvement of neural stem cells in adult neurogenesis so as to encourage its development as a therapeutic option. Copyright © 2013 Elsevier Ltd. All rights reserved.

  17. Cancer treatment in childhood and testicular function: the importance of the somatic environment

    Science.gov (United States)

    Stukenborg, Jan-Bernd; Jahnukainen, Kirsi; Hutka, Marsida

    2018-01-01

    Testicular function and future fertility may be affected by cancer treatment during childhood. Whilst survival of the germ (stem) cells is critical for ensuring the potential for fertility in these patients, the somatic cell populations also play a crucial role in providing a suitable environment to support germ cell maintenance and subsequent development. Regulation of the spermatogonial germ-stem cell niche involves many signalling pathways with hormonal influence from the hypothalamo-pituitary-gonadal axis. In this review, we describe the somatic cell populations that comprise the testicular germ-stem cell niche in humans and how they may be affected by cancer treatment during childhood. We also discuss the experimental models that may be utilized to manipulate the somatic environment and report the results of studies that investigate the potential role of somatic cells in the protection of the germ cells in the testis from cancer treatment. PMID:29351905

  18. Concomitant targeting of multiple key transcription factors effectively disrupts cancer stem cells enriched in side population of human pancreatic cancer cells.

    Directory of Open Access Journals (Sweden)

    Xiyan Wang

    Full Text Available A major challenge in the treatment of pancreatic ductal adenocarcinoma is the failure of chemotherapy, which is likely due to the presence of the cancer stem cells (CSCs.To identify side population (SP cells and characterize s-like properties in human pancreatic cancer cell lines (h-PCCLs and to exploit the efficacy of concomitant targeting of multiple key transcription factors governing the stemness of pancreatic CSCs in suppressing CSC-like phenotypes.Flow cytometry and Hoechst 33342 DNA-binding dye efflux assay were used to sort SP and non-SP (NSP cells from three h-PCCLs: PANC-1, SW1990, and BxPc-3. The self-renewal ability, invasiveness, migration and drug resistance of SP cells were evaluated. Expression of CSC marker genes was analyzed. Tumorigenicity was assessed using a xenograft model in nude mice. Effects of a complex decoy oligonucleotide (cdODN-SCO designed to simultaneously targeting Sox2, Oct4 and c-Myc were assessed.CSCs were enriched in the side proportion (SP cells contained in the h-PCCLs and they possessed aggressive growth, invasion, migration and drug-resistance properties, compared with NSP cells. SP cells overexpressed stem cell markers CD133 and ALDH1, pluripotency maintaining factors Nanog, Sox2 and Oct4, oncogenic transcription factor c-Myc, signaling molecule Notch1, and drug resistant gene ABCG2. Moreover, SP cells consistently demonstrated significantly greater tumorigenicity than NSP cells in xenograft model of nude mice. CdODN-SOC efficiently suppressed all CSC properties and phenotypes, and minimized the tumorigenic capability of the SP cells and the resistance to chemotherapy. By comparison, the negative control failed to do so.The findings indicate that targeting the key genes conferring the stemness of CSCs can efficiently eliminate CSC-like phenotypes, and thus may be considered a new approach for cancer therapy. Specifically, the present study establishes the combination of Sox2/Oct4/c-Myc targeting as a

  19. Colorectal cancer stem cells.

    Science.gov (United States)

    Salama, Paul; Platell, Cameron

    2009-10-01

    Somatic stem cells reside at the base of the crypts throughout the colonic mucosa. These cells are essential for the normal regeneration of the colonic epithelium. The stem cells reside within a special 'niche' comprised of intestinal sub-epithelial myofibroblasts that tightly control their function. It has been postulated that mutations within these adult colonic stem cells may induce neoplastic changes. Such cells can then dissociate from the epithelium and travel into the mesenchyme and thus form invasive cancers. 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 tumour. It is this group of cells that exhibits characteristics of colonic stem cells. Although anti-neoplastic agents can induce remissions by inhibiting cell division, the stem cells appear to be remarkably resistant to both standard chemotherapy and radiotherapy. These stem cells may therefore persist after treatment and form the nucleus for cancer recurrence. Hence, future treatment modalities should focus specifically on controlling the cancer stem cells. In this review, we discuss the biology of normal and malignant colonic stem cells.

  20. Combination cell therapy with mesenchymal stem cells and neural stem cells for brain stroke in rats.

    Science.gov (United States)

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

    2015-05-01

    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. 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. 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. 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.

  1. Identification and characterization of cells with cancer stem cell properties in human primary lung cancer cell lines.

    Directory of Open Access Journals (Sweden)

    Ping Wang

    Full Text Available Lung cancer (LC with its different subtypes is generally known as a therapy resistant cancer with the highest morbidity rate worldwide. Therapy resistance of a tumor is thought to be related to cancer stem cells (CSCs within the tumors. There have been indications that the lung cancer is propagated and maintained by a small population of CSCs. To study this question we established a panel of 15 primary lung cancer cell lines (PLCCLs from 20 fresh primary tumors using a robust serum-free culture system. We subsequently focused on identification of lung CSCs by studying these cell lines derived from 4 representative lung cancer subtypes such as small cell lung cancer (SCLC, large cell carcinoma (LCC, squamous cell carcinoma (SCC and adenocarcinoma (AC. We identified a small population of cells strongly positive for CD44 (CD44(high and a main population which was either weakly positive or negative for CD44 (CD44(low/-. Co-expression of CD90 further narrowed down the putative stem cell population in PLCCLs from SCLC and LCC as spheroid-forming cells were mainly found within the CD44(highCD90(+ sub-population. Moreover, these CD44(highCD90(+ cells revealed mesenchymal morphology, increased expression of mesenchymal markers N-Cadherin and Vimentin, increased mRNA levels of the embryonic stem cell related genes Nanog and Oct4 and increased resistance to irradiation compared to other sub-populations studied, suggesting the CD44(highCD90(+ population a good candidate for the lung CSCs. Both CD44(highCD90(+ and CD44(highCD90(- cells in the PLCCL derived from SCC formed spheroids, whereas the CD44(low/- cells were lacking this potential. These results indicate that CD44(highCD90(+ sub-population may represent CSCs in SCLC and LCC, whereas in SCC lung cancer subtype, CSC potentials were found within the CD44(high sub-population.

  2. Identification and Characterization of Cells with Cancer Stem Cell Properties in Human Primary Lung Cancer Cell Lines

    Science.gov (United States)

    Suo, Zhenhe; Munthe, Else; Solberg, Steinar; Ma, Liwei; Wang, Mengyu; Westerdaal, Nomdo Anton Christiaan; Kvalheim, Gunnar; Gaudernack, Gustav

    2013-01-01

    Lung cancer (LC) with its different subtypes is generally known as a therapy resistant cancer with the highest morbidity rate worldwide. Therapy resistance of a tumor is thought to be related to cancer stem cells (CSCs) within the tumors. There have been indications that the lung cancer is propagated and maintained by a small population of CSCs. To study this question we established a panel of 15 primary lung cancer cell lines (PLCCLs) from 20 fresh primary tumors using a robust serum-free culture system. We subsequently focused on identification of lung CSCs by studying these cell lines derived from 4 representative lung cancer subtypes such as small cell lung cancer (SCLC), large cell carcinoma (LCC), squamous cell carcinoma (SCC) and adenocarcinoma (AC). We identified a small population of cells strongly positive for CD44 (CD44high) and a main population which was either weakly positive or negative for CD44 (CD44low/−). Co-expression of CD90 further narrowed down the putative stem cell population in PLCCLs from SCLC and LCC as spheroid-forming cells were mainly found within the CD44highCD90+ sub-population. Moreover, these CD44highCD90+ cells revealed mesenchymal morphology, increased expression of mesenchymal markers N-Cadherin and Vimentin, increased mRNA levels of the embryonic stem cell related genes Nanog and Oct4 and increased resistance to irradiation compared to other sub-populations studied, suggesting the CD44highCD90+ population a good candidate for the lung CSCs. Both CD44highCD90+ and CD44highCD90− cells in the PLCCL derived from SCC formed spheroids, whereas the CD44low/− cells were lacking this potential. These results indicate that CD44highCD90+ sub-population may represent CSCs in SCLC and LCC, whereas in SCC lung cancer subtype, CSC potentials were found within the CD44high sub-population. PMID:23469181

  3. Stem/progenitor cells in pituitary organ homeostasis and tumourigenesis

    Science.gov (United States)

    Manshaei, Saba

    2018-01-01

    Evidence for the presence of pituitary gland stem cells has been provided over the last decade using a combination of approaches including in vitro clonogenicity assays, flow cytometric side population analysis, immunohistochemical analysis and genetic approaches. These cells have been demonstrated to be able to self-renew and undergo multipotent differentiation to give rise to all hormonal lineages of the anterior pituitary. Furthermore, evidence exists for their contribution to regeneration of the organ and plastic responses to changing physiological demand. Recently, stem-like cells have been isolated from pituitary neoplasms raising the possibility that a cytological hierarchy exists, in keeping with the cancer stem cell paradigm. In this manuscript, we review the evidence for the existence of pituitary stem cells, their role in maintaining organ homeostasis and the regulation of their differentiation. Furthermore, we explore the emerging concept of stem cells in pituitary tumours and their potential roles in these diseases. PMID:28855316

  4. Dissection of a stem cell hierarchy in the human breast

    DEFF Research Database (Denmark)

    Rubner Fridriksdottir, Agla Jael

    and apoptosis during each menstrual cycle. These changes are most prominent during pregnancy, lactation and involution after breast feeding. These highly dynamic changes are thought to rely on the presence of a breast epithelial stem cell population (reviewed in (Fridriksdottir et al. 2005)). Nevertheless......, cellular pathways that contribute to adult human breast gland architecture and cell lineages have not been described. Here, I identify a candidate stem cell niche in ducts, and zones containing progenitor cells in lobules (Villadsen and Fridriksdottir et al. 2007). Putative stem cells residing in ducts......-rich extracellular matrix gel. Staining for the epithelial lineage markers, cytokeratins K14 and K19, further reveals multipotent cells in the stem cell zone and three lineage- restricted cell types outside this zone. Multiparameter cell sorting and functional characterization with reference to anatomical sites...

  5. Plant stem cell niches.

    Science.gov (United States)

    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.

  6. Epigenetic Regulation of Epidermal Stem Cell Biomarkers and Their Role in Wound Healing

    Directory of Open Access Journals (Sweden)

    Sabita N. Saldanha

    2015-12-01

    Full Text Available As an actively renewable tissue, changes in skin architecture are subjected to the regulation of stem cells that maintain the population of cells responsible for the formation of epidermal layers. Stems cells retain their self-renewal property and express biomarkers that are unique to this population. However, differential regulation of the biomarkers can initiate the pathway of terminal cell differentiation. Although, pockets of non-clarity in stem cell maintenance and differentiation in skin still exist, the influence of epigenetics in epidermal stem cell functions and differentiation in skin homeostasis and wound healing is clearly evident. The focus of this review is to discuss the epigenetic regulation of confirmed and probable epidermal stem cell biomarkers in epidermal stratification of normal skin and in diseased states. The role of epigenetics in wound healing, especially in diseased states of diabetes and cancer, will also be conveyed.

  7. Basal cell carcinoma preferentially arises from stem cells within hair follicle and mechanosensory niches.

    Science.gov (United States)

    Peterson, Shelby C; Eberl, Markus; Vagnozzi, Alicia N; Belkadi, Abdelmadjid; Veniaminova, Natalia A; Verhaegen, Monique E; Bichakjian, Christopher K; Ward, Nicole L; Dlugosz, Andrzej A; Wong, Sunny Y

    2015-04-02

    Basal cell carcinoma (BCC) is characterized by frequent loss of PTCH1, leading to constitutive activation of the Hedgehog pathway. Although the requirement for Hedgehog in BCC is well established, the identity of disease-initiating cells and the compartments in which they reside remain controversial. By using several inducible Cre drivers to delete Ptch1 in different cell compartments in mice, we show here that multiple hair follicle stem cell populations readily develop BCC-like tumors. In contrast, stem cells within the interfollicular epidermis do not efficiently form tumors. Notably, we observed that innervated Gli1-expressing progenitors within mechanosensory touch dome epithelia are highly tumorigenic. Sensory nerves activate Hedgehog signaling in normal touch domes, while denervation attenuates touch dome-derived tumors. Together, our studies identify varying tumor susceptibilities among different stem cell populations in the skin, highlight touch dome epithelia as "hot spots" for tumor formation, and implicate cutaneous nerves as mediators of tumorigenesis. Copyright © 2015 Elsevier Inc. All rights reserved.

  8. I Want More and Better Cells! - An Outreach Project about Stem Cells and Its Impact on the General Population.

    Science.gov (United States)

    Varela Amaral, Sara; Forte, Teresa; Ramalho-Santos, João; Girão da Cruz, M Teresa

    2015-01-01

    Although science and technology impact every aspect of modern societies, there is still an extensive gap between science and society, which impairs the full exercise of citizenship. In the particular case of biomedical research increased investment should be accompanied by parallel efforts in terms of public information and engagement. We have carried out a project involving the production and evaluation of educational contents focused on stem cells - illustrated newspaper chronicles, radio interviews, a comic book, and animated videos - and monitored their impact on the Portuguese population. The study of the outreach materials in a heterogeneous sample of the population suggests that they are valuable tools to disseminate scientific messages, and that this is especially true for the comic-book format. Furthermore, the data showed that clear and stimulating outreach materials, that are able to teach new concepts and to promote critical thinking, increase engagement in science at different levels, depending on the depth of the concepts involved. Additionally, these materials can influence political, social and personal attitudes toward science. These results, together with the importance attributed to scientific research in stem cells by the population sampled, validates the diffusion of such materials as a significant contribution towards an overall public understanding and engagement in contemporary science, and this strategy should thus be considered in future projects. Regardless, stringent quality control must be implemented in order to efficiently communicate accurate scientific developments, and the public stimulated in terms of finding additional sources of reliable information.

  9. Isolation and functional interrogation of adult human prostate epithelial stem cells at single cell resolution.

    Science.gov (United States)

    Hu, Wen-Yang; Hu, Dan-Ping; Xie, Lishi; Li, Ye; Majumdar, Shyama; Nonn, Larisa; Hu, Hong; Shioda, Toshi; Prins, Gail S

    2017-08-01

    Using primary cultures of normal human prostate epithelial cells, we developed a novel prostasphere-based, label-retention assay that permits identification and isolation of stem cells at a single cell level. Their bona fide stem cell nature was corroborated using in vitro and in vivo regenerative assays and documentation of symmetric/asymmetric division. Robust WNT10B and KRT13 levels without E-cadherin or KRT14 staining distinguished individual stem cells from daughter progenitors in spheroids. Following FACS to isolate label-retaining stem cells from label-free progenitors, RNA-seq identified unique gene signatures for the separate populations which may serve as useful biomarkers. Knockdown of KRT13 or PRAC1 reduced sphere formation and symmetric self-renewal highlighting their role in stem cell maintenance. Pathways analysis identified ribosome biogenesis and membrane estrogen-receptor signaling enriched in stem cells with NF-ĸB signaling enriched in progenitors; activities that were biologically confirmed. Further, bioassays identified heightened autophagy flux and reduced metabolism in stem cells relative to progenitors. These approaches similarly identified stem-like cells from prostate cancer specimens and prostate, breast and colon cancer cell lines suggesting wide applicability. Together, the present studies isolate and identify unique characteristics of normal human prostate stem cells and uncover processes that maintain stem cell homeostasis in the prostate gland. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  10. Isolation and functional interrogation of adult human prostate epithelial stem cells at single cell resolution

    Directory of Open Access Journals (Sweden)

    Wen-Yang Hu

    2017-08-01

    Full Text Available Using primary cultures of normal human prostate epithelial cells, we developed a novel prostasphere-based, label-retention assay that permits identification and isolation of stem cells at a single cell level. Their bona fide stem cell nature was corroborated using in vitro and in vivo regenerative assays and documentation of symmetric/asymmetric division. Robust WNT10B and KRT13 levels without E-cadherin or KRT14 staining distinguished individual stem cells from daughter progenitors in spheroids. Following FACS to isolate label-retaining stem cells from label-free progenitors, RNA-seq identified unique gene signatures for the separate populations which may serve as useful biomarkers. Knockdown of KRT13 or PRAC1 reduced sphere formation and symmetric self-renewal highlighting their role in stem cell maintenance. Pathways analysis identified ribosome biogenesis and membrane estrogen-receptor signaling enriched in stem cells with NF-ĸB signaling enriched in progenitors; activities that were biologically confirmed. Further, bioassays identified heightened autophagy flux and reduced metabolism in stem cells relative to progenitors. These approaches similarly identified stem-like cells from prostate cancer specimens and prostate, breast and colon cancer cell lines suggesting wide applicability. Together, the present studies isolate and identify unique characteristics of normal human prostate stem cells and uncover processes that maintain stem cell homeostasis in the prostate gland.

  11. Studies of hematopoietic stem cells spared by 5-fluorouracil

    International Nuclear Information System (INIS)

    Van Zant, G.

    1984-01-01

    Mouse marrow cells were exposed to 5-fluorouracil (FU) either in vivo or in vitro and the effects on the hematopoietic stem cell compartment were studied. The drug was highly toxic to bone marrow cells including the spleen colony-forming unit (CFU-S) population. The small population of stem cells surviving FU, however, caused a different pattern of spleen colony growth when injected into lethally irradiated mice. Whereas numbers of spleen colonies caused by normal marrow cells remained constant during an 8-14 d period after transplantation, spleen colonies derived from FU-treated marrow cells increased by as much as 100-fold during this time. This effect on stem cells was dose dependent both in vitro and in vivo. When FU was given in vivo, the day 14/day 8 ratio of colonies was greatest 1 d after injection and, over the next 7 d, returned to a near-normal value, that is, unity. A number of studies have shown that the stem cell compartment is heterogeneous with respect to self-replicative capacity and developmental potential. An age structure for the stem cell compartment has been proposed wherein cells with a short mitotic history are more likely to self-replicate than they are to differentiate; hence they are more primitive. I propose that the delayed spleen colony appearance in normal hosts is the result of developmental maturation of the primitive stem cell compartment that survives FU and is responsible for spleen colonies arising around day 14. This maturation, at least initially, occurs in the marrow and leads to the replenishment of the more differentiated CFU-S subsets ablated by FU, which are normally responsible for spleen colonies appearing earlier after transplantation

  12. Stepwise development of hematopoietic stem cells from embryonic stem cells.

    Directory of Open Access Journals (Sweden)

    Kenji Matsumoto

    Full Text Available The cellular ontogeny of hematopoietic stem cells (HSCs remains poorly understood because their isolation from and their identification in early developing small embryos are difficult. We attempted to dissect early developmental stages of HSCs using an in vitro mouse embryonic stem cell (ESC differentiation system combined with inducible HOXB4 expression. Here we report the identification of pre-HSCs and an embryonic type of HSCs (embryonic HSCs as intermediate cells between ESCs and HSCs. Both pre-HSCs and embryonic HSCs were isolated by their c-Kit(+CD41(+CD45(- phenotype. Pre-HSCs did not engraft in irradiated adult mice. After co-culture with OP9 stromal cells and conditional expression of HOXB4, pre-HSCs gave rise to embryonic HSCs capable of engraftment and long-term reconstitution in irradiated adult mice. Blast colony assays revealed that most hemangioblast activity was detected apart from the pre-HSC population, implying the early divergence of pre-HSCs from hemangioblasts. Gene expression profiling suggests that a particular set of transcripts closely associated with adult HSCs is involved in the transition of pre-HSC to embryonic HSCs. We propose an HSC developmental model in which pre-HSCs and embryonic HSCs sequentially give rise to adult types of HSCs in a stepwise manner.

  13. Improved survival of multiple myeloma patients with late relapse after high-dose treatment and stem cell support, a population-based study of 348 patients in Denmark in 1994-2004

    DEFF Research Database (Denmark)

    Vangsted, Annette Juul; Klausen, Tobias W; Andersen, Niels F

    2010-01-01

    To analyse if patients with early relapse after high-dose chemotherapy with stem cell support (HDT) benefit from new treatment strategies in a population-based setting.......To analyse if patients with early relapse after high-dose chemotherapy with stem cell support (HDT) benefit from new treatment strategies in a population-based setting....

  14. [Origins and selection of epidermal progenitors and stem cells: a challenge for tissue engineering].

    Science.gov (United States)

    Deshayes, Nathalie; Rathman-Josserand, Michelle

    2008-01-01

    The use of epidermal stem cells and their progeny for tissue engineering and cell therapy represents a source of hope and major interest in view of applications such as replacing the loss of functionality in failing tissues or obtaining physiologic skin equivalents for skin grafting. The use of such cells necessitates the isolation and purification of rare populations of keratinocytes and then increasing their numbers by mass culture. This is not currently possible since part of the specific phenotype of these cells is lost once the cells are placed in culture. Furthermore, few techniques are available to unequivocally detect the presence of skin stem cells and/or their progeny in culture and thus quantify them. Two different sources of stem cells are currently being studied for skin research and clinical applications: skin progenitors either obtained from embryonic stem cells (ESC) or from selection from adult skin tissue. It has been shown that "keratinocyte-like" cells can be derived from ESC; however, the culturing processes must still be optimized to allow for the mass culture of homogeneous populations at a controlled stage of differentiation. The functional characterization of such populations must also be more thoroughly achieved. In order to use stem cells from adult tissues, improvements must be made in order to obtain a satisfactory degree of purification and characterization of this rare population. Distinguishing stem cells from progenitor cells at the molecular level also remains a challenge. Furthermore, stem cell research inevitably requires cultivating these cells outside their physiological environment or niche. It will thus be necessary to better understand the impact of this specific environmental niche on the preservation of the cellular phenotypes of interest.

  15. Exosomes and Their Therapeutic Potentials of Stem Cells

    Directory of Open Access Journals (Sweden)

    Chao Han

    2016-01-01

    Full Text Available Exosomes, a group of vesicles originating from the multivesicular bodies (MVBs, are released into the extracellular space when MVBs fuse with the plasma membrane. Numerous studies indicate that exosomes play important roles in cell-to-cell communication, and exosomes from specific cell types and conditions display multiple functions such as exerting positive effects on regeneration in many tissues. It is widely accepted that the therapeutic potential of stem cells may be mediated largely by the paracrine factors, so harnessing the paracrine effects of stem and progenitor cells without affecting these living, replicating, and potentially pluripotent cell populations is an advantage in terms of safety and complexity. Ascending evidence indicated that exosomes might be the main components of paracrine factors; thus, understanding the role of exosomes in each subtype of stem cells is far-reaching. In this review, we discuss the functions of exosomes from different types of stem cells and emphasize the therapeutic potentials of exosomes, providing an alternative way of developing strategies to cure diseases.

  16. Nestin-positive mesenchymal stem cells favour the astroglial lineage in neural progenitors and stem cells by releasing active BMP4

    Directory of Open Access Journals (Sweden)

    Leprince Pierre

    2004-09-01

    Full Text Available Abstract Background Spontaneous repair is limited after CNS injury or degeneration because neurogenesis and axonal regrowth rarely occur in the adult brain. As a result, cell transplantation has raised much interest as potential treatment for patients with CNS lesions. Several types of cells have been considered as candidates for such cell transplantation and replacement therapies. Foetal brain tissue has already been shown to have significant effects in patients with Parkinson's disease. Clinical use of the foetal brain tissue is, however, limited by ethical and technical problems as it requires high numbers of grafted foetal cells and immunosuppression. Alternatively, several reports suggested that mesenchymal stem cells, isolated from adult bone marrow, are multipotent cells and could be used in autograft approach for replacement therapies. Results In this study, we addressed the question of the possible influence of mesenchymal stem cells on neural stem cell fate. We have previously reported that adult rat mesenchymal stem cells are able to express nestin in defined culture conditions (in the absence of serum and after 25 cell population doublings and we report here that nestin-positive (but not nestin-negative mesenchymal stem cells are able to favour the astroglial lineage in neural progenitors and stem cells cultivated from embryonic striatum. The increase of the number of GFAP-positive cells is associated with a significant decrease of the number of Tuj1- and O4-positive cells. Using quantitative RT-PCR, we demonstrate that mesenchymal stem cells express LIF, CNTF, BMP2 and BMP4 mRNAs, four cytokines known to play a role in astroglial fate decision. In this model, BMP4 is responsible for the astroglial stimulation and oligodendroglial inhibition, as 1 this cytokine is present in a biologically-active form only in nestin-positive mesenchymal stem cells conditioned medium and 2 anti-BMP4 antibodies inhibit the nestin-positive mesenchymal

  17. Development of hematopoietic stem and progenitor cells from human pluripotent stem cells.

    Science.gov (United States)

    Chen, Tong; Wang, Fen; Wu, Mengyao; Wang, Zack Z

    2015-07-01

    Human pluripotent stem cells (hPSCs), including human embryonic stem cells (hESCs) and human induced pluripotent stem cells (hiPSCs), provide a new cell source for regenerative medicine, disease modeling, drug discovery, and preclinical toxicity screening. Understanding of the onset and the sequential process of hematopoietic cells from differentiated hPSCs will enable the achievement of personalized medicine and provide an in vitro platform for studying of human hematopoietic development and disease. During embryogenesis, hemogenic endothelial cells, a specified subset of endothelial cells in embryonic endothelium, are the primary source of multipotent hematopoietic stem cells. In this review, we discuss current status in the generation of multipotent hematopoietic stem and progenitor cells from hPSCs via hemogenic endothelial cells. We also review the achievements in direct reprogramming from non-hematopoietic cells to hematopoietic stem and progenitor cells. Further characterization of hematopoietic differentiation in hPSCs will improve our understanding of blood development and expedite the development of hPSC-derived blood products for therapeutic purpose. © 2015 Wiley Periodicals, Inc.

  18. Impact of thymectomy and antilymphocytic serum on stem cells of the intestinal epithelium

    International Nuclear Information System (INIS)

    Aparovich, G.G.; Trufakin, V.A.

    1982-01-01

    The population of stem cells of the intestinal epithelium was studied under conditions of the disturbed balance in the immune system on F 1 (CBAxC57B1) mice. It has been shown that thymectomy in adult mice does not influence the stem region of the intestinal epithelium at early time of observation but causes a tendency to the changed number of epithelial stem cells in 4-6 months. Administration of specific sera against T-, B- and mixed lymphoid populations on the 1st day of observation produces an ambi us effect on the stem region and results in an increase of the number of epithelial stem cells on the 5th day. After administration of the antilymphocytic serum there have been determined morphological changes in the population of mature erythrocytes and undulatory fluctuations in the number of mitotic cells of the intestinal epithelium. These data suggest functional correlation of the intestinal epithelium and the state of the immunocompetent tissue [ru

  19. Progenitor cell populations in the periodontal ligament of mice

    International Nuclear Information System (INIS)

    McCulloch, C.A.

    1985-01-01

    Stem cells in a variety of renewal tissues exhibit a slow rate of cell proliferation. The periodontal ligament of mouse molars was examined for the presence of slowly cycling progenitor cells to provide evidence for the existence of stem cells in this tissue. A pulse injection of 3 H-thymidine was administered and mice were sacrificed between 1 hour and 14 days after injection. Analysis of radioautographs using percentage of labeled cells and grain counts demonstrated that a population of label-retaining cells within 10 micron of blood vessels traversed the cell cycle more slowly than proliferating cells located greater than 10 micron from blood vessels. These data suggest that there is a slowly dividing population of progenitor cells in paravascular sites in mouse molar periodontal ligament which may be stem cells

  20. Glioblastoma-Initiating Cells: Relationship with Neural Stem Cells and the Micro-Environment

    Energy Technology Data Exchange (ETDEWEB)

    Goffart, Nicolas [Laboratory of Developmental Neurobiology, GIGA-Neurosciences Research Center, University of Liège, Liège 4000 (Belgium); Kroonen, Jérôme [Human Genetics, CHU and University of Liège, Liège 4000 (Belgium); The T& P Bohnenn Laboratory for Neuro-Oncology, Department of Neurology and Neurosurgery, UMC Utrecht, Utrecht 3556 (Netherlands); Rogister, Bernard, E-mail: Bernard.Register@ulg.ac.be [Laboratory of Developmental Neurobiology, GIGA-Neurosciences Research Center, University of Liège, Liège 4000 (Belgium); Department of Neurology, CHU and University of Liège, Liège 4000 (Belgium); GIGA-Development, Stem Cells and Regenerative Medicine, University of Liège, Liège 4000 (Belgium)

    2013-08-14

    Glioblastoma multiforme (GBM, WHO grade IV) is the most common and lethal subtype of primary brain tumor with a median overall survival of 15 months from the time of diagnosis. The presence in GBM of a cancer population displaying neural stem cell (NSC) properties as well as tumor-initiating abilities and resistance to current therapies suggests that these glioblastoma-initiating cells (GICs) play a central role in tumor development and are closely related to NSCs. However, it is nowadays still unclear whether GICs derive from NSCs, neural progenitor cells or differentiated cells such as astrocytes or oligodendrocytes. On the other hand, NSCs are located in specific regions of the adult brain called neurogenic niches that have been shown to control critical stem cell properties, to nourish NSCs and to support their self-renewal. This “seed-and-soil” relationship has also been adapted to cancer stem cell research as GICs also require a specific micro-environment to maintain their “stem cell” properties. In this review, we will discuss the controversies surrounding the origin and the identification of GBM stem cells and highlight the micro-environment impact on their biology.

  1. Glioblastoma-Initiating Cells: Relationship with Neural Stem Cells and the Micro-Environment

    International Nuclear Information System (INIS)

    Goffart, Nicolas; Kroonen, Jérôme; Rogister, Bernard

    2013-01-01

    Glioblastoma multiforme (GBM, WHO grade IV) is the most common and lethal subtype of primary brain tumor with a median overall survival of 15 months from the time of diagnosis. The presence in GBM of a cancer population displaying neural stem cell (NSC) properties as well as tumor-initiating abilities and resistance to current therapies suggests that these glioblastoma-initiating cells (GICs) play a central role in tumor development and are closely related to NSCs. However, it is nowadays still unclear whether GICs derive from NSCs, neural progenitor cells or differentiated cells such as astrocytes or oligodendrocytes. On the other hand, NSCs are located in specific regions of the adult brain called neurogenic niches that have been shown to control critical stem cell properties, to nourish NSCs and to support their self-renewal. This “seed-and-soil” relationship has also been adapted to cancer stem cell research as GICs also require a specific micro-environment to maintain their “stem cell” properties. In this review, we will discuss the controversies surrounding the origin and the identification of GBM stem cells and highlight the micro-environment impact on their biology

  2. Glioblastoma-Initiating Cells: Relationship with Neural Stem Cells and the Micro-Environment

    Directory of Open Access Journals (Sweden)

    Nicolas Goffart

    2013-08-01

    Full Text Available Glioblastoma multiforme (GBM, WHO grade IV is the most common and lethal subtype of primary brain tumor with a median overall survival of 15 months from the time of diagnosis. The presence in GBM of a cancer population displaying neural stem cell (NSC properties as well as tumor-initiating abilities and resistance to current therapies suggests that these glioblastoma-initiating cells (GICs play a central role in tumor development and are closely related to NSCs. However, it is nowadays still unclear whether GICs derive from NSCs, neural progenitor cells or differentiated cells such as astrocytes or oligodendrocytes. On the other hand, NSCs are located in specific regions of the adult brain called neurogenic niches that have been shown to control critical stem cell properties, to nourish NSCs and to support their self-renewal. This “seed-and-soil” relationship has also been adapted to cancer stem cell research as GICs also require a specific micro-environment to maintain their “stem cell” properties. In this review, we will discuss the controversies surrounding the origin and the identification of GBM stem cells and highlight the micro-environment impact on their biology.

  3. Epidermal stem cells response to radiative genotoxic stress

    International Nuclear Information System (INIS)

    Marie, Melanie

    2013-01-01

    mechanisms of stress response in the two cell populations. Taken together, data obtained during my PhD allowed us to show that stem cells respond differently than keratinocyte progenitors to radiation stress, and that they developed both intrinsic and radiation-induced strategies allowing a better protection. When comparing gamma Rays and UVB, we found that, although their toxic effects on skin share many similarities, the mechanisms set up by human epidermal stem cells to protect themselves vary according to the type of radiation stress. (author) [fr

  4. The suture provides a niche for mesenchymal stem cells of craniofacial bones

    Science.gov (United States)

    Zhao, Hu; Feng, Jifan; Ho, Thach-Vu; Grimes, Weston; Urata, Mark; Chai, Yang

    2015-01-01

    Bone tissue undergoes constant turnover supported by stem cells. Recent studies showed that perivascular mesenchymal stem cells (MSCs) contribute to the turnover of long bones. Craniofacial bones are flat bones derived from a different embryonic origin than the long bones. The identity and regulating niche for craniofacial bone MSCs remain unknown. Here, we identify Gli1+ cells within the suture mesenchyme as the major MSC population for craniofacial bones. They are not associated with vasculature, give rise to all craniofacial bones in the adult and are activated during injury repair. Gli1+ cells are typical MSCs in vitro. Ablation of Gli1+ cells leads to craniosynostosis and arrest of skull growth, indicating these cells are an indispensible stem cell population. Twist1+/− mice with craniosynostosis show reduced Gli1+ MSCs in sutures, suggesting that craniosynostosis may result from diminished suture stem cells. Our study indicates that craniofacial sutures provide a unique niche for MSCs for craniofacial bone homeostasis and repair. PMID:25799059

  5. Pluripotent stem cell-derived neural stem cells: From basic research to applications

    OpenAIRE

    Otsu, Masahiro; Nakayama, Takashi; Inoue, Nobuo

    2014-01-01

    Basic research on pluripotent stem cells is designed to enhance understanding of embryogenesis, whereas applied research is designed to develop novel therapies and prevent diseases. Attainment of these goals has been enhanced by the establishment of embryonic stem cell lines, the technological development of genomic reprogramming to generate induced-pluripotent stem cells, and improvements in vitro techniques to manipulate stem cells. This review summarizes the techniques required to generate...

  6. Dynamic changes in mouse hematopoietic stem cell numbers during aging

    NARCIS (Netherlands)

    de Haan, G; Van Zant, G

    1999-01-01

    To address the fundamental question of whether or not stem cell populations age, we performed quantitative measurements of the cycling status and frequency of hematopoietic stem cells in long-lived C57BL/6 (B6) and short-lived DBA/2 (DBA) mice at different developmental and aging stages. The

  7. Effect of hydroxyurea and vinblastine on the proliferation of the pluripotential stem cells

    International Nuclear Information System (INIS)

    Necas, E.; Neuwirt, J.

    1977-01-01

    The population of the pluripotential hemopoietic stem cells in mice, i.e., cells forming colonies in the spleens of lethally irradiated mice (colony forming cells CFc) proliferates relatively slowly. After partial damage the population regenerates which is achieved by an increased proliferation rate. The effect of damage caused by different doses of hydroxyurea or vinblastine to the proliferation of the CFc was investigated. CFc population was measured in femur bone marrow after the grafting of a bone marrow sample into lethally irradiated mice recipients (spleen colony method). The proliferation rate was estimated either according to the magnitude of the fraction of cells synthesizing DNA in the S phase of the cell cycle, or according to the sensitivity of the population to repeated injections of vinblastine. Data showed that even after very minute damage by hydroxyurea the stem cells started to proliferate intensively. The effect was dose dependent. The comparable damage caused by vinblastine had a significantly weaker effect on the proliferation of the stem cells. It is concluded from the results that the proliferation response of the pluripotential stem cells depends on two factors: the extent of the damage caused to the hemopoietic tissue and the position of the killed cells in the cell cycle. (author)

  8. Concise review: preleukemic stem cells: molecular biology and clinical implications of the precursors to leukemia stem cells.

    Science.gov (United States)

    Pandolfi, Ashley; Barreyro, Laura; Steidl, Ulrich

    2013-02-01

    Recent experimental evidence has shown that acute myeloid leukemia (AML) and myelodysplastic syndromes (MDS) arise from transformed immature hematopoietic cells following the accumulation of multiple stepwise genetic and epigenetic changes in hematopoietic stem cells and committed progenitors. The series of transforming events initially gives rise to preleukemic stem cells (pre-LSC), preceding the formation of fully transformed leukemia stem cells (LSC). Despite the established use of poly-chemotherapy, relapse continues to be the most common cause of death in AML and MDS. The therapeutic elimination of all LSC, as well as pre-LSC, which provide a silent reservoir for the re-formation of LSC, will be essential for achieving lasting cures. Conventional sequencing and next-generation genome sequencing have allowed us to describe many of the recurrent mutations in the bulk cell populations in AML and MDS, and recent work has also focused on identifying the initial molecular changes contributing to leukemogenesis. Here we review recent and ongoing advances in understanding the roles of pre-LSC, and the aberrations that lead to pre-LSC formation and subsequent LSC transformation.

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

    Science.gov (United States)

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

    2012-01-01

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

  10. Stem cell therapy for diabetes

    Directory of Open Access Journals (Sweden)

    K O Lee

    2012-01-01

    Full Text Available Stem cell therapy holds immense promise for the treatment of patients with diabetes mellitus. Research on the ability of human embryonic stem cells to differentiate into islet cells has defined the developmental stages and transcription factors involved in this process. However, the clinical applications of human embryonic stem cells are limited by ethical concerns, as well as the potential for teratoma formation. As a consequence, alternative forms of stem cell therapies, such as induced pluripotent stem cells, umbilical cord stem cells and bone marrow-derived mesenchymal stem cells, have become an area of intense study. Recent advances in stem cell therapy may turn this into a realistic treatment for diabetes in the near future.

  11. Specific Tandem 3'UTR Patterns and Gene Expression Profiles in Mouse Thy1+ Germline Stem Cells.

    Directory of Open Access Journals (Sweden)

    Yan Huang

    Full Text Available A recently developed strategy of sequencing alternative polyadenylation (APA sites (SAPAS with second-generation sequencing technology can be used to explore complete genome-wide patterns of tandem APA sites and global gene expression profiles. spermatogonial stem cells (SSCs maintain long-term reproductive abilities in male mammals. The detailed mechanisms by which SSCs self-renew and generate mature spermatozoa are not clear. To understand the specific alternative polyadenylation pattern and global gene expression profile of male germline stem cells (GSCs, mainly referred to SSCs here, we isolated and purified mouse Thy1+ cells from testis by magnetic-activated cell sorting (MACS and then used the SAPAS method for analysis, using pluripotent embryonic stem cells (ESCs and differentiated mouse embryonic fibroblast cells (MEFs as controls. As a result, we obtained 99,944 poly(A sites, approximately 40% of which were newly detected in our experiments. These poly(A sites originated from three mouse cell types and covered 17,499 genes, including 831 long non-coding RNA (lncRNA genes. We observed that GSCs tend to have shorter 3'UTR lengths while MEFs tend towards longer 3'UTR lengths. We also identified 1337 genes that were highly expressed in GSCs, and these genes were highly consistent with the functional characteristics of GSCs. Our detailed bioinformatics analysis identified APA site-switching events at 3'UTRs and many new specifically expressed genes in GSCs, which we experimentally confirmed. Furthermore, qRT-PCR was performed to validate several events of the 334 genes with distal-to-proximal poly(A switch in GSCs. Consistently APA reporter assay confirmed the total 3'UTR shortening in GSCs compared to MEFs. We also analyzed the cis elements around the proximal poly(A site preferentially used in GSCs and found C-rich elements may contribute to this regulation. Overall, our results identified the expression level and polyadenylation site

  12. Specific Tandem 3'UTR Patterns and Gene Expression Profiles in Mouse Thy1+ Germline Stem Cells

    Science.gov (United States)

    Lin, Zhuoheng; Feng, Xuyang; Jiang, Xue; Songyang, Zhou; Huang, Junjiu

    2015-01-01

    A recently developed strategy of sequencing alternative polyadenylation (APA) sites (SAPAS) with second-generation sequencing technology can be used to explore complete genome-wide patterns of tandem APA sites and global gene expression profiles. spermatogonial stem cells (SSCs) maintain long-term reproductive abilities in male mammals. The detailed mechanisms by which SSCs self-renew and generate mature spermatozoa are not clear. To understand the specific alternative polyadenylation pattern and global gene expression profile of male germline stem cells (GSCs, mainly referred to SSCs here), we isolated and purified mouse Thy1+ cells from testis by magnetic-activated cell sorting (MACS) and then used the SAPAS method for analysis, using pluripotent embryonic stem cells (ESCs) and differentiated mouse embryonic fibroblast cells (MEFs) as controls. As a result, we obtained 99,944 poly(A) sites, approximately 40% of which were newly detected in our experiments. These poly(A) sites originated from three mouse cell types and covered 17,499 genes, including 831 long non-coding RNA (lncRNA) genes. We observed that GSCs tend to have shorter 3'UTR lengths while MEFs tend towards longer 3'UTR lengths. We also identified 1337 genes that were highly expressed in GSCs, and these genes were highly consistent with the functional characteristics of GSCs. Our detailed bioinformatics analysis identified APA site-switching events at 3'UTRs and many new specifically expressed genes in GSCs, which we experimentally confirmed. Furthermore, qRT-PCR was performed to validate several events of the 334 genes with distal-to-proximal poly(A) switch in GSCs. Consistently APA reporter assay confirmed the total 3'UTR shortening in GSCs compared to MEFs. We also analyzed the cis elements around the proximal poly(A) site preferentially used in GSCs and found C-rich elements may contribute to this regulation. Overall, our results identified the expression level and polyadenylation site profiles and

  13. Template DNA-strand co-segregation and asymmetric cell division in skeletal muscle stem cells.

    Science.gov (United States)

    Shinin, Vasily; Gayraud-Morel, Barbara; Tajbakhsh, Shahragim

    2009-01-01

    Stem cells are present in all tissues and organs, and are crucial for normal regulated growth. How the pool size of stem cells and their progeny is regulated to establish the tissue prenatally, then maintain it throughout life, is a key question in biology and medicine. The ability to precisely locate stem and progenitors requires defining lineage progression from stem to differentiated cells, assessing the mode of cell expansion and self-renewal and identifying markers to assess the different cell states within the lineage. We have shown that during lineage progression from a quiescent adult muscle satellite cell to a differentiated myofibre, both symmetric and asymmetric divisions take place. Furthermore, we provide evidence that a sub-population of label retaining satellite cells co-segregate template DNA strands to one daughter cell. These findings provide a means of identifying presumed stem and progenitor cells within the lineage. In addition, asymmetric segregation of template DNA and the cytoplasmic protein Numb provides a landmark to define cell behaviour as self-renewal and differentiation decisions are being executed.

  14. Induced pluripotent stem (iPS) cells from human fetal stem cells.

    Science.gov (United States)

    Guillot, Pascale V

    2016-02-01

    Pluripotency defines the ability of stem cells to differentiate into all the lineages of the three germ layers and self-renew indefinitely. Somatic cells can regain the developmental potential of embryonic stem cells following ectopic expression of a set of transcription factors or, in certain circumstances, via modulation of culture conditions and supplementation with small molecule, that is, induced pluripotent stem (iPS) cells. Here, we discuss the use of fetal tissues for reprogramming, focusing in particular on stem cells derived from human amniotic fluid, and the development of chemical reprogramming. We next address the advantages and disadvantages of deriving pluripotent cells from fetal tissues and the potential clinical applications. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. Lifespan Extension and Sustained Expression of Stem Cell Phenotype of Human Breast Epithelial Stem Cells in a Medium with Antioxidants

    Directory of Open Access Journals (Sweden)

    Kai-Hung Wang

    2016-01-01

    Full Text Available 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.

  16. The requirement for freshly isolated human colorectal cancer (CRC) cells in isolating CRC stem cells.

    Science.gov (United States)

    Fan, F; Bellister, S; Lu, J; Ye, X; Boulbes, D R; Tozzi, F; Sceusi, E; Kopetz, S; Tian, F; Xia, L; Zhou, Y; Bhattacharya, R; Ellis, L M

    2015-02-03

    Isolation of colorectal cancer (CRC) cell populations enriched for cancer stem cells (CSCs) may facilitate target identification. There is no consensus regarding the best methods for isolating CRC stem cells (CRC-SCs). We determined the suitability of various cellular models and various stem cell markers for the isolation of CRC-SCs. Established human CRC cell lines, established CRC cell lines passaged through mice, patient-derived xenograft (PDX)-derived cells, early passage/newly established cell lines, and cells directly from clinical specimens were studied. Cells were FAC-sorted for the CRC-SC markers CD44, CD133, and aldehyde dehydrogenase (ALDH). Sphere formation and in vivo tumorigenicity studies were used to validate CRC-SC enrichment. None of the markers studied in established cell lines, grown either in vitro or in vivo, consistently enriched for CRC-SCs. In the three other cellular models, CD44 and CD133 did not reliably enrich for stemness. In contrast, freshly isolated PDX-derived cells or early passage/newly established CRC cell lines with high ALDH activity formed spheres in vitro and enhanced tumorigenicity in vivo, whereas cells with low ALDH activity did not. PDX-derived cells, early passages/newly established CRC cell lines and cells from clinical specimen with high ALDH activity can be used to identify CRC-SC-enriched populations. Established CRC cell lines should not be used to isolate CSCs.

  17. The role of microRNAs in stemness of cancer stem cells

    Directory of Open Access Journals (Sweden)

    Seyed Mohammad Ali Hosseini Rad

    2013-12-01

    Full Text Available Cancer is one of the most important diseases of humans, for which no cure has been found so far. Understanding the causes of cancer can pave the way for its treatment. Alteration in genetic elements such as oncogenes and tumor suppressor genes results in cancer. The most recent theory for the origin of cancer has been provided by cancer stem cells (CSCs. Tumor-initiating cells (T-ICs or CSCs are a small population isolated from tumors and hematologic malignancies. Since CSCs are similar to embryonic stem cells (ESCs in many aspects (such as pluripotency and self-renewal, recognizing the signaling pathways through which ESCs maintain their stemness can also help identify CSC signaling. One component of these signaling pathways is non-coding RNAs (ncRNAs. ncRNAs are classified in two groups: microRNAs (miRNAs and long non-coding RNAs (lncRNAs. miRNAs undergo altered expression in cancer. In this regard, they are classified as Onco-miRNAs or tumor suppressor miRNAs. Some miRNAs play similar roles in ESCs and CSCs, such as let-7 and miR-302. This review focuses on the miRNAs involved in stemness of ESCs and CSCs by presenting a summary of the role of miRNAs in other tumor cells.

  18. Stem cell clinics online: the direct-to-consumer portrayal of stem cell medicine.

    Science.gov (United States)

    Lau, Darren; Ogbogu, Ubaka; Taylor, Benjamin; Stafinski, Tania; Menon, Devidas; Caulfield, Timothy

    2008-12-04

    Despite the immature state of stem cell medicine, patients are seeking and accessing putative stem cell therapies in an "early market" in which direct-to-consumer advertising via the internet likely plays an important role. We analyzed stem cell clinic websites and appraised the relevant published clinical evidence of stem cell therapies to address three questions about the direct-to-consumer portrayal of stem cell medicine in this early market: What sorts of therapies are being offered? How are they portrayed? Is there clinical evidence to support the use of these therapies? We found that the portrayal of stem cell medicine on provider websites is optimistic and unsubstantiated by peer-reviewed literature.

  19. [Progress in epidermal stem cells].

    Science.gov (United States)

    Wang, Li-Juan; Wang, You-Liang; Yang, Xiao

    2010-03-01

    Mammalian skin epidermis contains different epidermal stem cell pools which contribute to the homeostasis and repair of skin epithelium. Epidermal stem cells possess two essential features common to all stem cells: self-renewal and differentiation. Disturbing the balance between self-renewal and differentiation of epidermal stem cell often causes tumors or other skin diseases. Epidermal stem cell niches provide a special microenvironment that maintains a balance of stem cell quiescence and activity. This review primarily concentrates on the following points of the epidermal stem cells: the existing evidences, the self-renewal and differentiation, the division pattern, the signal pathways regulating self-renewal and differentiation, and the microenvironment (niche) and macroenvironment maintaining the homeostasis of stem cells.

  20. A Bilayer Construct Controls Adipose-Derived Stem Cell Differentiation into Endothelial Cells and Pericytes without Growth Factor Stimulation

    Science.gov (United States)

    2011-01-01

    A Bilayer Construct Controls Adipose-Derived Stem Cell Differentiation into Endothelial Cells and Pericytes Without Growth Factor Stimulation...Ph.D.3 This work describes the differentiation of adipose-derived mesenchymal stem cells (ASC) in a composite hy- drogel for use as a vascularized...tissue from a single population of ASC. This work underscores the importance of the extracellular matrix in controlling stem cell phenotype. It is our

  1. Targeting neuroblastoma stem cells with retinoic acid and proteasome inhibitor.

    Directory of Open Access Journals (Sweden)

    Barbara Hämmerle

    Full Text Available Neuroblastma cell lines contain a side-population of cells which express stemness markers. These stem-like cells may represent the potential underlying mechanism for resistance to conventional therapy and recurrence of neuroblastoma in patients.To develop novel strategies for targeting the side-population of neurobastomas, we analyzed the effects of 13-cis-retinoic acid (RA combined with the proteasome inhibitor MG132. The short-term action of the treatment was compared with effects after a 5-day recovery period during which both chemicals were withdrawn. RA induced growth arrest and differentiation of SH-SY5Y and SK-N-BE(2 neuroblastoma cell lines. Inhibition of the proteasome caused apoptosis in both cell lines, thus, revealing the critical role of this pathway in the regulated degradation of proteins involved in neuroblastoma proliferation and survival. The combination of RA with MG132 induced apoptosis in a dose-dependent manner, in addition to promoting G2/M arrest in treated cultures. Interestingly, expression of stem cell markers such as Nestin, Sox2, and Oct4 were reduced after the recovery period of combined treatment as compared with untreated cells or treated cells with either compound alone. Consistent with this, neurosphere formation was significantly impaired by the combined treatment of RA and MG132.Given that stem-like cells are associated with resistant to conventional therapy and are thought to be responsible for relapse, our results suggest that dual therapy of RA and proteasome inhibitor might be beneficial for targeting the side-population of cells associated residual disease in high-risk neuroblastoma.

  2. Proteome of human stem cells from periodontal ligament and dental pulp.

    Directory of Open Access Journals (Sweden)

    Enrica Eleuterio

    Full Text Available BACKGROUND: Many adult tissues contain a population of stem cells with the ability to regenerate structures similar to the microenvironments from which they are derived in vivo and represent a promising therapy for the regeneration of complex tissues in the clinical disorder. Human adult stem cells (SCs including bone marrow stem cells (BMSCs, dental pulp stem cells (DPSCs and periodontal ligament stem cells (PDLSCs have been characterized for their high proliferative potential, expression of characteristic SC-associated markers and for the plasticity to differentiate in different lineage in vitro. METHODOLOGY/PRINCIPAL FINDINGS: The aim of this study is to define the molecular features of stem cells from oral tissue by comparing the proteomic profiles obtained with 2-DE followed by MALDI-TOF/TOF of ex-vivo cultured human PDLSCs, DPSCs and BMSCs. Our results showed qualitative similarities in the proteome profiles among the SCs examined including some significant quantitative differences. To enrich the knowledge of oral SCs proteome we performed an analysis in narrow range pH 4-7 and 6-9, and we found that DPSCs vs PDLSCs express differentially regulated proteins that are potentially related to growth, regulation and genesis of neuronal cells, suggesting that SCs derived from oral tissue source populations may possess the potential ability of neuronal differentiation which is very consistent with their neural crest origin. CONCLUSION/SIGNIFICANCE: This study identifies some differentially expressed proteins by using comparative analysis between DPSCs and PDLSCs and BMSCs and suggests that stem cells from oral tissue could have a different cell lineage potency compared to BMSCs.

  3. Engineering stem cell niches in bioreactors

    OpenAIRE

    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 “ni...

  4. Cancer stemness and metastatic potential of the novel tumor cell line K3: an inner mutated cell of bone marrow-derived mesenchymal stem cells.

    Science.gov (United States)

    Qian, Hui; Ding, Xiaoqing; Zhang, Jiao; Mao, Fei; Sun, Zixuan; Jia, Haoyuan; Yin, Lei; Wang, Mei; Zhang, Xu; Zhang, Bin; Yan, Yongmin; Zhu, Wei; Xu, Wenrong

    2017-06-13

    Mesenchymal stem cells (MSCs) transplantation has been used for therapeutic applications in various diseases. Here we report MSCs can malignantly transform in vivo. The novel neoplasm was found on the tail of female rat after injection with male rat bone marrow-derived MSCs (rBM-MSCs) and the new tumor cell line, K3, was isolated from the neoplasm. The K3 cells expressed surface antigens and pluripotent genes similar to those of rBM-MSCs and presented tumor cell features. Moreover, the K3 cells contained side population cells (SP) like cancer stem cells (CSCs), which might contribute to K3 heterogeneity and tumorigenic capacity. To investigate the metastatic potential of K3 cells, we established the nude mouse models of liver and lung metastases and isolated the corresponding metastatic cell lines K3-F4 and K3-B6. Both K3-F4 and K3-B6 cell lines with higher metastatic potential acquired more mesenchymal and stemness-related features. Epithelial-mesenchymal transition is a potential mechanism of K3-F4 and K3-B6 formation.

  5. Induced pluripotent stem (iPS) cells from human fetal stem cells

    OpenAIRE

    Guillot, P. V.

    2016-01-01

    Pluripotency defines the ability of stem cells to differentiate into all the lineages of the three germ layers and self-renew indefinitely. Somatic cells can regain the developmental potential of embryonic stem cells following ectopic expression of a set of transcription factors or, in certain circumstances, via modulation of culture conditions and supplementation with small molecule, that is, induced pluripotent stem (iPS) cells. Here, we discuss the use of fetal tissues for reprogramming, f...

  6. Efficient generation of induced pluripotent stem cells from human bone marrow mesenchymal stem cells.

    Science.gov (United States)

    Yulin, X; Lizhen, L; Lifei, Z; Shan, F; Ru, L; Kaimin, H; Huang, H

    2012-01-01

    Ectopic expression of defined sets of genetic factors can reprogramme somatic cells to induced pluripotent stem cells (iPSCs) that closely resemble embryonic stem cells. However, the low reprogramming efficiency is a significant handicap for mechanistic studies and potential clinical application. In this study, we used human bone marrow-derived mesenchymal stem cells (hBMMSCs) as target cells for reprogramming and investigated efficient iPSC generation from hBMMSCs using the compounds of p53 siRNA, valproic acid (VPA) and vitamin C (Vc) with four transcription factors OCT4, SOX2, KLF4, and c-MYC (compound induction system). The synergetic mechanism of the compounds was studied. Our results showed that the compound induction system could efficiently reprogramme hBMMSCs to iPSCs. hBMMSC-derived iPSC populations expressed pluripotent markers and had multi-potential to differentiate into three germ layer-derived cells. p53 siRNA, VPA and Vc had a synergetic effect on cell reprogramming and the combinatorial use of these substances greatly improved the efficiency of iPSC generation by suppressing the expression of p53, decreasing cell apoptosis, up-regulating the expression of the pluripotent gene OCT4 and modifying the cell cycle. Therefore, our study highlights a straightforward method for improving the speed and efficiency of iPSC generation and provides versatile tools for investigating early developmental processes such as haemopoiesis and relevant diseases. In addition, this study provides a paradigm for the combinatorial use of genetic factors and molecules to improve the efficiency of iPSC generation.

  7. New insights into mechanisms of stem cell daughter fate determination in regenerative tissues.

    Science.gov (United States)

    Sada, Aiko; Tumbar, Tudorita

    2013-01-01

    Stem cells can self-renew and differentiate over extended periods of time. Understanding how stem cells acquire their fates is a central question in stem cell biology. Early work in Drosophila germ line and neuroblast showed that fate choice is achieved by strict asymmetric divisions that can generate each time one stem and one differentiated cell. More recent work suggests that during homeostasis, some stem cells can divide symmetrically to generate two differentiated cells or two identical stem cells to compensate for stem cell loss that occurred by direct differentiation or apoptosis. The interplay of all these factors ensures constant tissue regeneration and the maintenance of stem cell pool size. This interplay can be modeled as a population-deterministic dynamics that, at least in some systems, may be described as stochastic behavior. Here, we overview recent progress made on the characterization of stem cell dynamics in regenerative tissues. Copyright © 2013 Elsevier Inc. All rights reserved.

  8. Identification and molecular regulation of neural stem cells in the olfactory epithelium

    International Nuclear Information System (INIS)

    Beites, Crestina L.; Kawauchi, Shimako; Crocker, Candice E.; Calof, Anne L.

    2005-01-01

    The sensory neurons that subserve olfaction, olfactory receptor neurons (ORNs), are regenerated throughout life, making the neuroepithelium in which they reside [the olfactory epithelium (OE)] an excellent model for studying how intrinsic and extrinsic factors regulate stem cell dynamics and neurogenesis during development and regeneration. Numerous studies indicate that transcription factors and signaling molecules together regulate generation of ORNs from stem and progenitor cells during development, and work on regenerative neurogenesis indicates that these same factors may operate at postnatal ages as well. This review describes our current knowledge of the identity of the OE neural stem cell; the different cell types that are thought to be the progeny (directly or indirectly) of this stem cell; and the factors that influence cell differentiation in the OE neuronal lineage. We review data suggesting that (1) the ORN lineage contains three distinct proliferating cell types-a stem cell and two populations of transit amplifying cells; (2) in established OE, these three cell types are present within the basal cell compartment of the epithelium; and (3) the stem cell that gives rise ultimately to ORNs may also generate two glial cell types of the primary olfactory pathway: sustentacular cells (SUS), which lie within OE proper; and olfactory ensheathing cells (OEC), which envelope the olfactory nerve. In addition, we describe factors that are both made by and found within the microenvironment of OE stem and progenitor cells, and which exert crucial growth regulatory effects on these cells. Thus, as with other regenerating tissues, the basis of regeneration in the OE appears be a population of stem cells, which resides within a microenvironment (niche) consisting of factors crucial for maintenance of its capacity for proliferation and differentiation

  9. Augmentation of musculoskeletal regeneration: role for pluripotent stem cells.

    Science.gov (United States)

    Jevons, Lauren A; Houghton, Franchesca D; Tare, Rahul S

    2018-03-20

    The rise in the incidence of musculoskeletal diseases is attributed to an increasing ageing population. The debilitating effects of musculoskeletal diseases, coupled with a lack of effective therapies, contribute to huge financial strains on healthcare systems. The focus of regenerative medicine has shifted to pluripotent stem cells (PSCs), namely, human embryonic stem cells and human-induced PSCs, due to the limited success of adult stem cell-based interventions. PSCs constitute a valuable cell source for musculoskeletal regeneration due to their capacity for unlimited self-renewal, ability to differentiate into all cell lineages of the three germ layers and perceived immunoprivileged characteristics. This review summarizes methods for chondrogenic, osteogenic, myogenic and adipogenic differentiation of PSCs and their potential for therapeutic applications.

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

    Directory of Open Access Journals (Sweden)

    Shengxiu Li

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

  11. Characterization of deciduous teeth stem cells isolated from crown dental pulp

    Directory of Open Access Journals (Sweden)

    Debeljak-Martačić Jasmina

    2014-01-01

    Full Text Available Background/Aim. The last decade has been profoundly marked by persistent attempts to use ex vivo expanded and manipulated mesenchymal stem cells (MSCs, as a tool in different types of regenerative therapy. In the present study we described immunophenotype and the proliferative and differentiation potential of cells isolated from pulp remnants of exfoliated deciduous teeth in the final phase of root resorption. Methods. The initial adherent cell population from five donors was obtained by the outgrowth method. Colony forming unit-fibroblast (CFU-F assay was performed in passage one. Cell expansion was performed until passage three and all tests were done until passage eight. Cells were labeled for early mesenchymal stem cells markers and analysis have been done using flow cytometry. The proliferative potential was assessed by cell counting in defined time points and population doubling time was calculated. Commercial media were used to induce osteoblastic, chondrogenic and adipogenic differentiation. Cytology and histology methods were used for analysis of differentiated cell morphology and extracellular matrix characteristics. Results. According to immunophenotype analyses all undifferentiated cells were positive for the mesenchymal stem cell markers: CD29 and CD73. Some cells expressed CD146 and CD106. The hematopoietic cell marker, CD34, was not detected. In passage one, incidence of CFU-F was 4.7 ± 0.5/100. Population doubling time did not change significantly during cell subcultivation and was in average 25 h. After induction of differentiation, the multicolony derived cell population had a tri-lineage differentiation potential, since mineralized matrix, cartilage-like tissue and adipocytes were successfully formed after three weeks of incubation. Conclusion. Altogether, these data suggest that remnants of deciduous teeth dental pulp contained cell populations with mesenchymal stem cell-like features, with a high proliferation and

  12. Differentiation of breast cancer stem cells by knockdown of CD44: promising differentiation therapy

    Directory of Open Access Journals (Sweden)

    Pham Phuc V

    2011-12-01

    Full Text Available Abstract Background Breast cancer stem cells (BCSCs are the source of breast tumors. Compared with other cancer cells, cancer stem cells show high resistance to both chemotherapy and radiotherapy. Targeting of BCSCs is thus a potentially promising and effective strategy for breast cancer treatment. Differentiation therapy represents one type of cancer stem-cell-targeting therapy, aimed at attacking the stemness of cancer stem cells, thus reducing their chemo- and radioresistance. In a previous study, we showed that down-regulation of CD44 sensitized BCSCs to the anti-tumor agent doxorubicin. This study aimed to determine if CD44 knockdown caused BCSCs to differentiate into breast cancer non-stem cells (non-BCSCs. Methods We isolated a breast cancer cell population (CD44+CD24- cells from primary cultures of malignant breast tumors. These cells were sorted into four sub-populations based on their expression of CD44 and CD24 surface markers. CD44 knockdown in the BCSC population was achieved using small hairpin RNA lentivirus particles. The differentiated status of CD44 knock-down BCSCs was evaluated on the basis of changes in CD44+CD24- phenotype, tumorigenesis in NOD/SCID mice, and gene expression in relation to renewal status, metastasis, and cell cycle in comparison with BCSCs and non-BCSCs. Results Knockdown of CD44 caused BCSCs to differentiate into non-BCSCs with lower tumorigenic potential, and altered the cell cycle and expression profiles of some stem cell-related genes, making them more similar to those seen in non-BCSCs. Conclusions Knockdown of CD44 is an effective strategy for attacking the stemness of BCSCs, resulting in a loss of stemness and an increase in susceptibility to chemotherapy or radiation. The results of this study highlight a potential new strategy for breast cancer treatment through the targeting of BCSCs.

  13. I Want More and Better Cells! – An Outreach Project about Stem Cells and Its Impact on the General Population

    Science.gov (United States)

    Varela Amaral, Sara; Forte, Teresa; Ramalho-Santos, João; Girão da Cruz, M. Teresa

    2015-01-01

    Although science and technology impact every aspect of modern societies, there is still an extensive gap between science and society, which impairs the full exercise of citizenship. In the particular case of biomedical research increased investment should be accompanied by parallel efforts in terms of public information and engagement. We have carried out a project involving the production and evaluation of educational contents focused on stem cells - illustrated newspaper chronicles, radio interviews, a comic book, and animated videos - and monitored their impact on the Portuguese population. The study of the outreach materials in a heterogeneous sample of the population suggests that they are valuable tools to disseminate scientific messages, and that this is especially true for the comic-book format. Furthermore, the data showed that clear and stimulating outreach materials, that are able to teach new concepts and to promote critical thinking, increase engagement in science at different levels, depending on the depth of the concepts involved. Additionally, these materials can influence political, social and personal attitudes toward science. These results, together with the importance attributed to scientific research in stem cells by the population sampled, validates the diffusion of such materials as a significant contribution towards an overall public understanding and engagement in contemporary science, and this strategy should thus be considered in future projects. Regardless, stringent quality control must be implemented in order to efficiently communicate accurate scientific developments, and the public stimulated in terms of finding additional sources of reliable information. PMID:26222053

  14. Advances of mesenchymal stem cells derived from bone marrow and dental tissue in craniofacial tissue engineering.

    Science.gov (United States)

    Yang, Maobin; Zhang, Hongming; Gangolli, Riddhi

    2014-05-01

    Bone and dental tissues in craniofacial region work as an important aesthetic and functional unit. Reconstruction of craniofacial tissue defects is highly expected to ensure patients to maintain good quality of life. Tissue engineering and regenerative medicine have been developed in the last two decades, and been advanced with the stem cell technology. Bone marrow derived mesenchymal stem cells are one of the most extensively studied post-natal stem cell population, and are widely utilized in cell-based therapy. Dental tissue derived mesenchymal stem cells are a relatively new stem cell population that isolated from various dental tissues. These cells can undergo multilineage differentiation including osteogenic and odontogenic differentiation, thus provide an alternative source of mesenchymal stem cells for tissue engineering. In this review, we discuss the important issues in mesenchymal stem cell biology including the origin and functions of mesenchymal stem cells, compare the properties of these two types of mesenchymal cells, update recent basic research and clinic applications in this field, and address important future challenges.

  15. A revisionist history of adult marrow stem cell biology or 'they forgot about the discard'.

    Science.gov (United States)

    Quesenberry, P; Goldberg, L

    2017-08-01

    The adult marrow hematopoietic stem cell biology has largely been based on studies of highly purified stem cells. This is unfortunate because during the stem cell purification the great bulk of stem cells are discarded. These cells are actively proliferating. The final purified stem cell is dormant and not representative of the whole stem cell compartment. Thus, a large number of studies on the cellular characteristics, regulators and molecular details of stem cells have been carried on out of non-represented cells. Niche studies have largely pursued using these purified stem cells and these are largely un-interpretable. Other considerations include the distinction between baseline and transplant stem cells and the modulation of stem cell phenotype by extracellular vesicles, to cite a non-inclusive list. Work needs to proceed on characterizing the true stem cell population.

  16. CD90 and CD110 correlate with cancer stem cell potentials in human T-acute lymphoblastic leukemia cells

    International Nuclear Information System (INIS)

    Yamazaki, Hiroto; Nishida, Hiroko; Iwata, Satoshi; Dang, Nam H.; Morimoto, Chikao

    2009-01-01

    Although cancer stem cells (CSCs) have been recently identified in myeloid leukemia, published data on lymphoid malignancy have been sparse. T-acute lymphoblastic leukemia (T-ALL) is characterized by the abnormal proliferation of T-cell precursors and is generally aggressive. As CD34 is the only positive-selection marker for CSCs in T-ALL, we performed extensive analysis of CD markers in T-ALL cell lines. We found that some of the tested lines consisted of heterogeneous populations of cells with various levels of surface marker expression. In particular, a small subpopulation of CD90 (Thy-1) and CD110 (c-Mpl) were shown to correlate with stem cell properties both in vitro and in transplantation experiments. As these markers are expressed on hematopoietic stem cells, our results suggest that stem cell-like population are enriched in CD90+/CD110+ fraction and they are useful positive-selection markers for the isolation of CSCs in some cases of T-ALL.

  17. CD90 and CD110 correlate with cancer stem cell potentials in human T-acute lymphoblastic leukemia cells

    Energy Technology Data Exchange (ETDEWEB)

    Yamazaki, Hiroto; Nishida, Hiroko; Iwata, Satoshi [Division of Clinical Immunology, Advanced Clinical Research Center, Institute of Medical Science, University of Tokyo, Tokyo 108-8639 (Japan); Dang, Nam H. [Department of Hematologic Malignancies, Nevada Cancer Institute, Las Vegas, NV (United States); Morimoto, Chikao, E-mail: morimoto@ims.u-tokyo.ac.jp [Division of Clinical Immunology, Advanced Clinical Research Center, Institute of Medical Science, University of Tokyo, Tokyo 108-8639 (Japan)

    2009-05-29

    Although cancer stem cells (CSCs) have been recently identified in myeloid leukemia, published data on lymphoid malignancy have been sparse. T-acute lymphoblastic leukemia (T-ALL) is characterized by the abnormal proliferation of T-cell precursors and is generally aggressive. As CD34 is the only positive-selection marker for CSCs in T-ALL, we performed extensive analysis of CD markers in T-ALL cell lines. We found that some of the tested lines consisted of heterogeneous populations of cells with various levels of surface marker expression. In particular, a small subpopulation of CD90 (Thy-1) and CD110 (c-Mpl) were shown to correlate with stem cell properties both in vitro and in transplantation experiments. As these markers are expressed on hematopoietic stem cells, our results suggest that stem cell-like population are enriched in CD90+/CD110+ fraction and they are useful positive-selection markers for the isolation of CSCs in some cases of T-ALL.

  18. Nanotechnology & human stem cells: Applications in cardiogenesis and neurogenesis

    Science.gov (United States)

    Tomov, Martin L.

    Human stem cell research holds an unprecedented promise to revolutionize the way we approach medicine and healthcare in general, moving us from a position of mostly addressing the symptoms to a state where treatments can focus on removing the underlying causes of a condition. Stem cell research can shed light into normal developmental pathways, as we are beginning to replicate them in a petri dish and can also be used to model diseases and abnormal conditions. Direct applications can range from finding cures for single or multigene diseases to demonstrating that we can replace these genes with a normal copy. We can even begin to model lifelong conditions such as aging by iPSC technology by relying on fetal, young, adult, and centenarian populations to provide insights into the process. We have also begun to understand the microenvironment in which specific cell populations reside. Being able to replicate the chemical, physical mechanical, and spatial needs of those cells, research groups are successfully generating full organs using cadaver scaffolds of heart and kidney, and there is promising research to reach the same success with other organs, such as the liver, and pancreas. Advances in those areas open an enormous potential to study organs, organoids, organ valves, tubes or other functional elements such as beating cardiomyocytes in vitro. There is also the need to evaluate the whole genome of induced and differentiated cells, with its myriad of interacting pathways. Bioinformatics can help our understanding of embryogenesis, organ differentiation and function. It can also help optimize our stem cell and bio-scaffold tools to advance closer to functional organs and tissues. Such a combination approach will also include pluripotency evaluation and multi-lineage differentiation, as well as platforms that may assist in cell therapies: 3D structures, micro-ribbons, directed patterning to name a few. There is now a clearer path forward with stem cell research than

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

    Science.gov (United States)

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

    2013-01-01

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

  20. Angiopoietin-like protein 3 promotes preservation of stemness during ex vivo expansion of murine hematopoietic stem cells.

    Science.gov (United States)

    Farahbakhshian, Elnaz; Verstegen, Monique M; Visser, Trudi P; Kheradmandkia, Sima; Geerts, Dirk; Arshad, Shazia; Riaz, Noveen; Grosveld, Frank; van Til, Niek P; Meijerink, Jules P P

    2014-01-01

    Allogeneic hematopoietic stem cell (HSC) transplantations from umbilical cord blood or autologous HSCs for gene therapy purposes are hampered by limited number of stem cells. To test the ability to expand HSCs in vitro prior to transplantation, two growth factor cocktails containing stem cell factor, thrombopoietin, fms-related tyrosine kinase-3 ligand (STF) or stem cell factor, thrombopoietin, insulin-like growth factor-2, fibroblast growth factor-1 (STIF) either with or without the addition of angiopoietin-like protein-3 (Angptl3) were used. Culturing HSCs in STF and STIF media for 7 days expanded long-term repopulating stem cells content in vivo by ∼6-fold and ∼10-fold compared to freshly isolated stem cells. Addition of Angptl3 resulted in increased expansion of these populations by ∼17-fold and ∼32-fold, respectively, and was further supported by enforced expression of Angptl3 in HSCs through lentiviral transduction that also promoted HSC expansion. As expansion of highly purified lineage-negative, Sca-1+, c-Kit+ HSCs was less efficient than less pure lineage-negative HSCs, Angptl3 may have a direct effect on HCS but also an indirect effect on accessory cells that support HSC expansion. No evidence for leukemia or toxicity was found during long-term follow up of mice transplanted with ex vivo expanded HSCs or manipulated HSC populations that expressed Angptl3. We conclude that the cytokine combinations used in this study to expand HSCs ex vivo enhances the engraftment in vivo. This has important implications for allogeneic umbilical cord-blood derived HSC transplantations and autologous HSC applications including gene therapy.

  1. Functional genomic characterization of neoblast-like stem cells in larval Schistosoma mansoni

    Science.gov (United States)

    Wang, Bo; Collins, James J; Newmark, Phillip A

    2013-01-01

    Schistosomes infect hundreds of millions of people in the developing world. Transmission of these parasites relies on a stem cell-driven, clonal expansion of larvae inside a molluscan intermediate host. How this novel asexual reproductive strategy relates to current models of stem cell maintenance and germline specification is unclear. Here, we demonstrate that this proliferative larval cell population (germinal cells) shares some molecular signatures with stem cells from diverse organisms, in particular neoblasts of planarians (free-living relatives of schistosomes). We identify two distinct germinal cell lineages that differ in their proliferation kinetics and expression of a nanos ortholog. We show that a vasa/PL10 homolog is required for proliferation and maintenance of both populations, whereas argonaute2 and a fibroblast growth factor receptor-encoding gene are required only for nanos-negative cells. Our results suggest that an ancient stem cell-based developmental program may have enabled the evolution of the complex life cycle of parasitic flatworms. DOI: http://dx.doi.org/10.7554/eLife.00768.001 PMID:23908765

  2. Cancer stem cell overexpression of nicotinamide N-methyltransferase enhances cellular radiation resistance

    DEFF Research Database (Denmark)

    D’Andrea, Filippo P.; Safwat, Akmal; Kassem, Moustapha

    2011-01-01

    BackgroundCancer stem cells are thought to be a radioresistant population and may be the seeds for recurrence after radiotherapy. Using tumorigenic clones of retroviral immortalized human mesenchymal stem cell with small differences in their phenotype, we investigated possible genetic expression...

  3. Interplay between Inflammation and Stemness in Cancer Cells: The Role of Toll-Like Receptor Signaling

    Directory of Open Access Journals (Sweden)

    Da-Wei Yeh

    2016-01-01

    Full Text Available Cancer stem cells (CSCs are a small population of cancer cells that exhibit stemness. These cells contribute to cancer metastasis, treatment resistance, and relapse following therapy; therefore, they may cause malignancy and reduce the success of cancer treatment. Nuclear factor kappa B- (NF-κB- mediated inflammatory responses increase stemness in cancer cells, and CSCs constitutively exhibit higher NF-κB activation, which in turn increases their stemness. These opposite effects form a positive feedback loop that further amplifies inflammation and stemness in cancer cells, thereby expanding CSC populations in the tumor. Toll-like receptors (TLRs activate NF-κB-mediated inflammatory responses when stimulated by carcinogenic microbes and endogenous molecules released from cells killed during cancer treatment. NF-κB activation by extrinsic TLR ligands increases stemness in cancer cells. Moreover, it was recently shown that increased NF-κB activity and inflammatory responses in CSCs may be caused by altered TLR signaling during the enrichment of stemness in cancer cells. Thus, the activation of TLR signaling by extrinsic and intrinsic factors drives a positive interplay between inflammation and stemness in cancer cells.

  4. Production Methods for a Mesenchymal Stem Cell Therapeutic as a Medical Defense Countermeasure

    Science.gov (United States)

    2012-02-01

    mesenchymal stem cell (MSC) efficacy in a variety of injury models demonstrate the unique qualities of this reparative cell population to adapt to the...therapeutic product. Characterization of stem cell properties of culture-expanded MSCs is shown by in vitro differentiation to form mature cell types. The

  5. Effect of radiotherapy on stem cells in head and neck region

    International Nuclear Information System (INIS)

    Sharma, Anu; Krishnan, Manu

    2014-01-01

    Head and neck cancers form a major group of dreaded diseases in India. Radiation therapy is one important treatment modality for this type of cancer. However, inadvertent radiation to normal tissue leads to depletion of its critical stem cells due to genotoxic damage. Cells mostly affected by radiation are rapidly dividing bone marrow and epidermal skin stem cells. The erythroid and myeloid progenitor cells of bone marrow bear the brunt of it causing leucopenia/thrombocytopenia/anemia. Alopecia and pigmentation mark the changes on skin. In brain, two stem cell populations; subgranular and subventricular zones, where neurogenesis occurs throughout life are affected. However, terminally differentiating neurons with low proliferative capacity are spared. In oral tissues, xerostomia is a prominent feature, while dental pulp stem cells undergo senescence. Enamel calcification and tooth root formation are also impaired. Eye shows changes in the limbal stem cells that replace corneal epithelium. All these imply a varied response of stem cells to radiation therapy based on their proliferation capacity; quiescent stem cells being more resistant whereas actively dividing cells, less resistant to radiotherapy. This paper evaluates the differential response of stem cells to radiation therapy in the head and neck area and thereby aims to predict their therapeutic potential. (author)

  6. Biophotonics sensor acclimatization to stem cells environment

    Science.gov (United States)

    Mohamad Shahimin, Mukhzeer

    2017-11-01

    The ability to discriminate, characterise and purify biological cells from heterogeneous population of cells is fundamental to numerous prognosis and diagnosis applications; often forming the basis for current and emerging clinical protocols in stem cell therapy. Current sorting approaches exploit differences in cell density, specific immunologic targets, or receptor-ligand interactions to isolate particular cells. Identification of novel properties by which different cell types may be discerned and of new ways for their selective manipulation are clearly fundamental components for improving sorting methodologies. Biophotonics sensor developed by our team are potentially capable of discriminating cells according to their refractive index (which is highly dependable on the organelles inside the cell), size (indicator to cell stage) and shape (in certain cases as an indicator to cell type). The sensor, which already discriminate particles efficiently, is modified to acclimatize into biological environment, especially for stem cell applications.

  7. Aging-Induced Stem Cell Mutations as Drivers for Disease and Cancer

    Science.gov (United States)

    Adams, Peter D.; Jasper, Heinrich; Rudolph, K. Lenhard

    2015-01-01

    Aging is characterized by a decrease in genome integrity, impaired organ maintenance, and an increased risk of cancer, which coincide with clonal dominance of expanded mutant stem and progenitor cell populations in aging tissues, such as the intestinal epithelium, the hematopoietic system, and the male germline. Here we discuss possible explanations for age-associated increases in the initiation and/or progression of mutant stem/progenitor clones and highlight the roles of stem cell quiescence, replication-associated DNA damage, telomere shortening, epigenetic alterations, and metabolic challenges as determinants of stem cell mutations and clonal dominance in aging. PMID:26046760

  8. The Potential of Stem Cells in Treatment of Traumatic Brain Injury.

    Science.gov (United States)

    Weston, Nicole M; Sun, Dong

    2018-01-25

    Traumatic brain injury (TBI) is a global public health concern, with limited treatment options available. Despite improving survival rate after TBI, treatment is lacking for brain functional recovery and structural repair in clinic. Recent studies have suggested that the mature brain harbors neural stem cells which have regenerative capacity following brain insults. Much progress has been made in preclinical TBI model studies in understanding the behaviors, functions, and regulatory mechanisms of neural stem cells in the injured brain. Different strategies targeting these cell population have been assessed in TBI models. In parallel, cell transplantation strategy using a wide range of stem cells has been explored for TBI treatment in pre-clinical studies and some in clinical trials. This review summarized strategies which have been explored to enhance endogenous neural stem cell-mediated regeneration and recent development in cell transplantation studies for post-TBI brain repair. Thus far, neural regeneration through neural stem cells either by modulating endogenous neural stem cells or by stem cell transplantation has attracted much attention. It is highly speculated that targeting neural stem cells could be a potential strategy to repair and regenerate the injured brain. Neuroprotection and neuroregeneration are major aspects for TBI therapeutic development. With technique advancement, it is hoped that stem cell-based therapy targeting neuroregeneration will be able to translate to clinic in not so far future.

  9. Differential Cell Adhesion of Breast Cancer Stem Cells on Biomaterial Substrate with Nanotopographical Cues

    Directory of Open Access Journals (Sweden)

    Kenneth K.B. Tan

    2015-04-01

    Full Text Available Cancer stem cells are speculated to have the capability of self-renewal and re-establishment of tumor heterogeneity, possibly involved in the potential relapse of cancer. CD44+CD24−/lowESA+ cells have been reported to possess tumorigenic properties, and these biomarkers are thought to be highly expressed in breast cancer stem cells. Cell behavior can be influenced by biomolecular and topographical cues in the natural microenvironment. We hypothesized that different cell populations in breast cancer tissue exhibit different adhesion characteristics on substrates with nanotopography. Adhesion characterizations were performed using human mammary epithelial cells (HMEC, breast cancer cell line MCF7 and primary invasive ductal carcinoma (IDC cells obtained from patients’ samples, on micro- and nano-patterned poly-L-lactic acid (PLLA films. Topography demonstrated a significant effect on cell adhesion, and the effect was cell type dependent. Cells showed elongation morphology on gratings. The CD44+CD24−/lowESA+ subpopulation in MCF7 and IDC cells showed preferential adhesion on 350-nm gratings. Flow cytometry analysis showed that 350-nm gratings captured a significantly higher percentage of CD44+CD24− in MCF7. A slightly higher percentage of CD44+CD24−/lowESA+ was captured on the 350-nm gratings, although no significant difference was observed in the CD44+CD24−ESA+ in IDC cells across patterns. Taken together, the study demonstrated that the cancer stem cell subpopulation could be enriched using different nanopatterns. The enriched population could subsequently aid in the isolation and characterization of cancer stem cells.

  10. Targeting Wnt Signaling in Colon Cancer Stem Cells

    NARCIS (Netherlands)

    de Sousa E Melo, Felipe; Vermeulen, Louis; Richel, Dick; Medema, Jan Paul

    2011-01-01

    The identification of cancer stem cell (CSC) populations in virtually all tumor types has widespread clinical consequences. CSCs are suggested to be the only cells within malignancies endowed with tumorigenic capacity and are, therefore, directly implicated in therapy resistance and minimal residual

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

    Science.gov (United States)

    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. © 2014 International Federation for Cell Biology.

  12. Chinese newspaper coverage of (unproven) stem cell therapies and their providers.

    Science.gov (United States)

    Ogbogu, Ubaka; Du, Li; Rachul, Christen; Bélanger, Lisa; Caulfield, Timothy

    2013-04-01

    China is a primary destination for stem cell tourism, the phenomenon whereby patients travel abroad to receive unproven stem cell-based treatments that have not been approved in their home countries. Yet, much remains unknown about the state of the stem cell treatment industry in China and about how the Chinese view treatments and providers. Given the media's crucial role in science/health communication and in framing public dialogue, this study sought to examine Chinese newspaper portrayal and perceptions of stem cell treatments and their providers. Based on a content analysis of over 300 newspaper articles, the study revealed that while Chinese newspaper reporting is generally neutral in tone, it is also inaccurate, overly positive, heavily influenced by "interested" treatment providers and focused on the therapeutic uses of stem cells to address the health needs of the local population. The study findings suggest a need to counterbalance providers' influence on media reporting through strategies that encourage media uptake of accurate information about stem cell research and treatments.

  13. Radiosensitivity of hemopoietic stem cells on cloning in bone marrow and spleen

    International Nuclear Information System (INIS)

    Shvets, V.N.; Shafirkin, A.V.

    1979-01-01

    It was shown that population of stem cells from bone marrow of mice is heterogenous by radiosensitivity. A 55%-survival of CFU is exponential function of radiation dose (D 0 -9 rad). A dose-effect curve for radioresistant part of the population (D 0 =180 rad) is sygmoid (Dsub(q)=130 rad). Radiosensitive CFU are suggested to represent a primarily committed fraction of half-semi cells, and radioresistant CFU are referable to a pool of pluripotent stem cells. Heterogenous nature of CFU population is proved with different modifications of radiation effect and interactions of CFU with T-lymphocytes

  14. Multimodal Nanomedicine Strategies for Targeting Cancer Cells as well as Cancer Stem Cell Signalling Mechanisms.

    Science.gov (United States)

    Kanwar, Jagat R; Samarasinghe, Rasika M; Kamalapuram, Sishir K; Kanwar, Rupinder K

    2017-01-01

    Increasing evidence suggests that stem cells, a small population of cells with unique selfrenewable and tumour regenerative capacity, are aiding tumour re-growth and multidrug resistance. Conventional therapies are highly ineffective at eliminating these cells leading to relapse of disease and formation of chemoresistance tumours. Cancer and stem cells targeted therapies that utilizes nanotherapeutics to delivery anti-cancer drugs to specific sites are continuously investigated. This review focuses on recent research using nanomedicine and targeting entities to eliminate cancer cells and cancer stem cells. Current nanotherapeutics in clinical trials along with more recent publications on targeted therapies are addressed. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  15. Analysis of Neural Stem Cells from Human Cortical Brain Structures In Vitro.

    Science.gov (United States)

    Aleksandrova, M A; Poltavtseva, R A; Marei, M V; Sukhikh, G T

    2016-05-01

    Comparative immunohistochemical analysis of the neocortex from human fetuses showed that neural stem and progenitor cells are present in the brain throughout the gestation period, at least from week 8 through 26. At the same time, neural stem cells from the first and second trimester fetuses differed by the distribution, morphology, growth, and quantity. Immunocytochemical analysis of neural stem cells derived from fetuses at different gestation terms and cultured under different conditions showed their differentiation capacity. Detailed analysis of neural stem cell populations derived from fetuses on gestation weeks 8-9, 18-20, and 26 expressing Lex/SSEA1 was performed.

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

    International Nuclear Information System (INIS)

    Li Hongzhen; Zhou Jianjun; Miki, Jun; Furusato, Bungo; Gu Yongpeng; Srivastava, Shiv; McLeod, David G.; Vogel, Jonathan C.; Rhim, Johng S.

    2008-01-01

    Understanding prostate stem cells may provide insight into the origin of prostate cancer. Primary cells have been cultured from human prostate tissue but they usually survive only 15-20 population doublings before undergoing senescence. We report here that RC-170N/h/clone 7 cells, a clonal cell line from hTERT-immortalized primary non-malignant tissue-derived human prostate epithelial cell line (RC170N/h), retain multipotent stem cell properties. The RC-170N/h/clone 7 cells expressed a human embryonic stem cell marker, Oct-4, and potential prostate epithelial stem cell markers, CD133, integrin α2β1 hi and CD44. The RC-170N/h/clone 7 cells proliferated in KGM and Dulbecco's Modified Eagle Medium with 10% fetal bovine serum and 5 μg/ml insulin (DMEM + 10% FBS + Ins.) medium, and differentiated into epithelial stem cells that expressed epithelial cell markers, including CK5/14, CD44, p63 and cytokeratin 18 (CK18); as well as the mesenchymal cell markers, vimentin, desmin; the neuron and neuroendocrine cell marker, chromogranin A. Furthermore the RC170 N/h/clone 7 cells differentiated into multi tissues when transplanted into the sub-renal capsule and subcutaneously of NOD-SCID mice. The results indicate that RC170N/h/clone 7 cells retain the properties of multipotent stem cells and will be useful as a novel cell model for studying the mechanisms of human prostate stem cell differentiation and transformation

  17. Self-renewal molecular mechanisms of colorectal cancer stem cells.

    Science.gov (United States)

    Pan, Tianhui; Xu, Jinghong; Zhu, Yongliang

    2017-01-01

    Colorectal cancer stem cells (CCSCs) represent a small fraction of the colorectal cancer cell population that possess self-renewal and multi-lineage differentiation potential and drive tumorigenicity. Self-renewal is essential for the malignant biological behaviors of colorectal cancer stem cells. While the self-renewal molecular mechanisms of colorectal cancer stem cells are not yet fully understood, the aberrant activation of signaling pathways, such as Wnt, Notch, transforming growth factor-β (TGF-β)/bone morphogenetic protein (BMP) and Hedgehog-Gli (HH-GLI), specific roles mediated by cell surface markers and micro-environmental factors are involved in the regulation of self-renewal. The elucidation of the molecular mechanisms behind self-renewal may lead to the development of novel targeted interventions for the treatment of colorectal cancer.

  18. Mammary Stem Cells and Breast Cancer Stem Cells: Molecular Connections and Clinical Implications.

    Science.gov (United States)

    Celià-Terrassa, Toni

    2018-05-04

    Cancer arises from subpopulations of transformed cells with high tumor initiation and repopulation ability, known as cancer stem cells (CSCs), which share many similarities with their normal counterparts. In the mammary gland, several studies have shown common molecular regulators between adult mammary stem cells (MaSCs) and breast cancer stem cells (bCSCs). Cell plasticity and self-renewal are essential abilities for MaSCs to maintain tissue homeostasis and regenerate the gland after pregnancy. Intriguingly, these properties are similarly executed in breast cancer stem cells to drive tumor initiation, tumor heterogeneity and recurrence after chemotherapy. In addition, both stem cell phenotypes are strongly influenced by external signals from the microenvironment, immune cells and supportive specific niches. This review focuses on the intrinsic and extrinsic connections of MaSC and bCSCs with clinical implications for breast cancer progression and their possible therapeutic applications.

  19. Effect of Induced Pluripotent Stem Cell Technology in Blood Banking

    Science.gov (United States)

    Focosi, Daniele

    2016-01-01

    Summary Population aging has imposed cost-effective alternatives to blood donations. Artificial blood is still at the preliminary stages of development, and the need for viable cells seems unsurmountable. Because large numbers of viable cells must be promptly available for clinical use, stem cell technologies, expansion, and banking represent ideal tools to ensure a regular supply. Provided key donors can be identified, induced pluripotent stem cell (iPSC) technology could pave the way to a new era in transfusion medicine, just as it is already doing in many other fields of medicine. The present review summarizes the current state of research on iPSC technology in the field of blood banking, highlighting hurdles, and promises. Significance The aging population in Western countries is causing a progressive reduction of blood donors and a constant increase of blood recipients. Because blood is the main therapeutic option to treat acute hemorrhage, cost-effective alternatives to blood donations are being actively investigated. The enormous replication capability of induced pluripotent stem cells and their promising results in many other fields of medicine could be an apt solution to produce the large numbers of viable cells required in transfusion and usher in a new era in transfusion medicine. The present report describes the potentiality, technological hurdles, and promises of induced pluripotent stem cells to generate red blood cells by redifferentiation. PMID:26819256

  20. Understanding the application of stem cell therapy in cardiovascular diseases

    Directory of Open Access Journals (Sweden)

    Sharma RK

    2012-10-01

    Full Text Available Rakesh K Sharma, Donald J Voelker, Roma Sharma, Hanumanth K ReddyUniversity of Arkansas for Medical Sciences, Medical Center of South Arkansas, El Dorado, AR, USAAbstract: Throughout their lifetime, an individual may sustain many injuries and recover spontaneously over a period of time, without even realizing the injury in the first place. Wound healing occurs due to a proliferation of stem cells capable of restoring the injured tissue. The ability of adult stem cells to repair tissue is dependent upon the intrinsic ability of tissues to proliferate. The amazing capacity of embryonic stem cells to give rise to virtually any type of tissue has intensified the search for similar cell lineage in adults to treat various diseases including cardiovascular diseases. The ability to convert adult stem cells into pluripotent cells that resemble embryonic cells, and to transplant those in the desired organ for regenerative therapy is very attractive, and may offer the possibility of treating harmful disease-causing mutations. The race is on to find the best cells for treatment of cardiovascular disease. There is a need for the ideal stem cell, delivery strategies, myocardial retention, and time of administration in the ideal patient population. There are multiple modes of stem cell delivery to the heart with different cell retention rates that vary depending upon method and site of injection, such as intra coronary, intramyocardial or via coronary sinus. While there are crucial issues such as retention of stem cells, microvascular plugging, biodistribution, homing to myocardium, and various proapoptotic factors in the ischemic myocardium, the regenerative potential of stem cells offers an enormous impact on clinical applications in the management of cardiovascular diseases.Keywords: stem cell therapy, stem cell delivery, cardiovascular diseases, myocardial infarction, cardiomyopathy

  1. Stem cells in dentistry: A study regarding awareness of stem cells among dental professionals

    OpenAIRE

    Parita K Chitroda; Girish Katti; Nikhat M Attar; Syed Shahbaz; G Sreenivasarao; Ambika Patil

    2017-01-01

    Background: Dental stem cell, a type of adult stem cell, exhibits multipotent differentiation capacity and is drawing worldwide attention because of its numerous applications. The advances in applications of dental stem cells seem to be unsurpassed in the near future, for which specialized skills and knowledge in this arena are of prime significance. Hence, there is a need to acquire more knowledge about dental stem cells to obtain maximum benefits from it in the coming years. Dental stem cel...

  2. Nanoscale definition of substrate materials to direct human adult stem cells towards tissue specific populations.

    Science.gov (United States)

    Curran, Judith M; Chen, Rui; Stokes, Robert; Irvine, Eleanor; Graham, Duncan; Gubbins, Earl; Delaney, Deany; Amro, Nabil; Sanedrin, Raymond; Jamil, Haris; Hunt, John A

    2010-03-01

    The development of homogenously nano-patterned chemically modified surfaces that can be used to initiate a cellular response, particularly stem cell differentiation, in a highly controlled manner without the need for exogenous biological factors has never been reported, due to that fact that precisely defined and reproducible systems have not been available that can be used to study cell/material interactions and unlock the potential of a material driven cell response. Until now material driven stem cell (furthermore any cell) responses have been variable due to the limitations in definition and reproducibility of the underlying substrate and the lack of true homogeneity of modifications that can dictate a cellular response at a sub-micron level that can effectively control initial cell interactions of all cells that contact the surface. Here we report the successful design and use of homogenously molecularly nanopatterned surfaces to control initial stem cell adhesion and hence function. The highly specified nano-patterned arrays were compared directly to silane modified bulk coated substrates that have previously been proven to initiate mesenchymal stem cell (MSC) differentiation in a heterogenous manner, the aim of this study was to prove the efficiency of these previously observed cell responses could be enhanced by the incorporation of nano-patterns. Nano-patterned surfaces were prepared by Dip Pen Nanolithography (DPN) to produce arrays of 70 nm sized dots separated by defined spacings of 140, 280 and 1000 nm with terminal functionalities of carboxyl, amino, methyl and hydroxyl and used to control cell growth. These nanopatterned surfaces exhibited unprecedented control of initial cell interactions and will change the capabilities for stem cell definition in vitro and then cell based medical therapies. In addition to highlighting the ability of the materials to control stem cell functionality on an unprecedented scale this research also introduces the

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

    Science.gov (United States)

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

    2010-11-01

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

  4. Stem Cells and Engineered Scaffolds for Regenerative Wound Healing

    Directory of Open Access Journals (Sweden)

    Biraja C. Dash

    2018-03-01

    Full Text Available The normal wound healing process involves a well-organized cascade of biological pathways and any failure in this process leads to wounds becoming chronic. Non-healing wounds are a burden on healthcare systems and set to increase with aging population and growing incidences of obesity and diabetes. Stem cell-based therapies have the potential to heal chronic wounds but have so far seen little success in the clinic. Current research has been focused on using polymeric biomaterial systems that can act as a niche for these stem cells to improve their survival and paracrine activity that would eventually promote wound healing. Furthermore, different modification strategies have been developed to improve stem cell survival and differentiation, ultimately promoting regenerative wound healing. This review focuses on advanced polymeric scaffolds that have been used to deliver stem cells and have been tested for their efficiency in preclinical animal models of wounds.

  5. Stem Cells and Engineered Scaffolds for Regenerative Wound Healing.

    Science.gov (United States)

    Dash, Biraja C; Xu, Zhenzhen; Lin, Lawrence; Koo, Andrew; Ndon, Sifon; Berthiaume, Francois; Dardik, Alan; Hsia, Henry

    2018-03-09

    The normal wound healing process involves a well-organized cascade of biological pathways and any failure in this process leads to wounds becoming chronic. Non-healing wounds are a burden on healthcare systems and set to increase with aging population and growing incidences of obesity and diabetes. Stem cell-based therapies have the potential to heal chronic wounds but have so far seen little success in the clinic. Current research has been focused on using polymeric biomaterial systems that can act as a niche for these stem cells to improve their survival and paracrine activity that would eventually promote wound healing. Furthermore, different modification strategies have been developed to improve stem cell survival and differentiation, ultimately promoting regenerative wound healing. This review focuses on advanced polymeric scaffolds that have been used to deliver stem cells and have been tested for their efficiency in preclinical animal models of wounds.

  6. Catalog of gene expression in adult neural stem cells and their in vivo microenvironment

    International Nuclear Information System (INIS)

    Williams, Cecilia; Wirta, Valtteri; Meletis, Konstantinos; Wikstroem, Lilian; Carlsson, Leif; Frisen, Jonas; Lundeberg, Joakim

    2006-01-01

    Stem cells generally reside in a stem cell microenvironment, where cues for self-renewal and differentiation are present. However, the genetic program underlying stem cell proliferation and multipotency is poorly understood. Transcriptome analysis of stem cells and their in vivo microenvironment is one way of uncovering the unique stemness properties and provides a framework for the elucidation of stem cell function. Here, we characterize the gene expression profile of the in vivo neural stem cell microenvironment in the lateral ventricle wall of adult mouse brain and of in vitro proliferating neural stem cells. We have also analyzed an Lhx2-expressing hematopoietic-stem-cell-like cell line in order to define the transcriptome of a well-characterized and pure cell population with stem cell characteristics. We report the generation, assembly and annotation of 50,792 high-quality 5'-end expressed sequence tag sequences. We further describe a shared expression of 1065 transcripts by all three stem cell libraries and a large overlap with previously published gene expression signatures for neural stem/progenitor cells and other multipotent stem cells. The sequences and cDNA clones obtained within this framework provide a comprehensive resource for the analysis of genes in adult stem cells that can accelerate future stem cell research

  7. Dental pulp pluripotent-like stem cells (DPPSC), a new stem cell population with chromosomal stability and osteogenic capacity for biomaterials evaluation.

    Science.gov (United States)

    Núñez-Toldrà, Raquel; Martínez-Sarrà, Ester; Gil-Recio, Carlos; Carrasco, Miguel Ángel; Al Madhoun, Ashraf; Montori, Sheyla; Atari, Maher

    2017-04-21

    Biomaterials are widely used to regenerate or substitute bone tissue. In order to evaluate their potential use for clinical applications, these need to be tested and evaluated in vitro with cell culture models. Frequently, immortalized osteoblastic cell lines are used in these studies. However, their uncontrolled proliferation rate, phenotypic changes or aberrations in mitotic processes limits their use in long-term investigations. Recently, we described a new pluripotent-like subpopulation of dental pulp stem cells derived from the third molars (DPPSC) that shows genetic stability and shares some pluripotent characteristics with embryonic stem cells. In this study we aim to describe the use of DPPSC to test biomaterials, since we believe that the biomaterial cues will be more critical in order to enhance the differentiation of pluripotent stem cells. The capacity of DPPSC to differentiate into osteogenic lineage was compared with human sarcoma osteogenic cell line (SAOS-2). Collagen and titanium were used to assess the cell behavior in commonly used biomaterials. The analyses were performed by flow cytometry, alkaline phosphatase and mineralization stains, RT-PCR, immunohistochemistry, scanning electron microscopy, Western blot and enzymatic activity. Moreover, the genetic stability was evaluated and compared before and after differentiation by short-comparative genomic hybridization (sCGH). DPPSC showed excellent differentiation into osteogenic lineages expressing bone-related markers similar to SAOS-2. When cells were cultured on biomaterials, DPPSC showed higher initial adhesion levels. Nevertheless, their osteogenic differentiation showed similar trend among both cell types. Interestingly, only DPPSC maintained a normal chromosomal dosage before and after differentiation on 2D monolayer and on biomaterials. Taken together, these results promote the use of DPPSC as a new pluripotent-like cell model to evaluate the biocompatibility and the differentiation

  8. The Androgen Receptor Bridges Stem Cell-Associated Signaling Nodes in Prostate Stem Cells

    Directory of Open Access Journals (Sweden)

    Alastair H. Davies

    2016-01-01

    Full Text Available The therapeutic potential of stem cells relies on dissecting the complex signaling networks that are thought to regulate their pluripotency and self-renewal. Until recently, attention has focused almost exclusively on a small set of “core” transcription factors for maintaining the stem cell state. It is now clear that stem cell regulatory networks are far more complex. In this review, we examine the role of the androgen receptor (AR in coordinating interactions between signaling nodes that govern the balance of cell fate decisions in prostate stem cells.

  9. Cancer stem cells and differentiation therapy.

    Science.gov (United States)

    Jin, Xiong; Jin, Xun; Kim, Hyunggee

    2017-10-01

    Cancer stem cells can generate tumors from only a small number of cells, whereas differentiated cancer cells cannot. The prominent feature of cancer stem cells is its ability to self-renew and differentiate into multiple types of cancer cells. Cancer stem cells have several distinct tumorigenic abilities, including stem cell signal transduction, tumorigenicity, metastasis, and resistance to anticancer drugs, which are regulated by genetic or epigenetic changes. Like normal adult stem cells involved in various developmental processes and tissue homeostasis, cancer stem cells maintain their self-renewal capacity by activating multiple stem cell signaling pathways and inhibiting differentiation signaling pathways during cancer initiation and progression. Recently, many studies have focused on targeting cancer stem cells to eradicate malignancies by regulating stem cell signaling pathways, and products of some of these strategies are in preclinical and clinical trials. In this review, we describe the crucial features of cancer stem cells related to tumor relapse and drug resistance, as well as the new therapeutic strategy to target cancer stem cells named "differentiation therapy."

  10. Generation of Human Induced Pluripotent Stem Cells from Peripheral Blood Mononuclear Cells Using Sendai Virus.

    Science.gov (United States)

    Soares, Filipa A C; Pedersen, Roger A; Vallier, Ludovic

    2016-01-01

    This protocol describes the efficient isolation of peripheral blood mononuclear cells from circulating blood via density gradient centrifugation and subsequent generation of integration-free human induced pluripotent stem cells. Peripheral blood mononuclear cells are cultured for 9 days to allow expansion of the erythroblast population. The erythroblasts are then used to derive human induced pluripotent stem cells using Sendai viral vectors, each expressing one of the four reprogramming factors Oct4, Sox2, Klf4, and c-Myc.

  11. [Embryonic stem cells. Future perspectives].

    Science.gov (United States)

    Groebner, M; David, R; Franz, W M

    2006-05-01

    Embryonic stem cells (ES cells) are able to differentiate into any cell type, and therefore represent an excellent source for cellular replacement therapies in the case of widespread diseases, for example heart failure, diabetes, Parkinson's disease and spinal cord injury. A major prerequisite for their efficient and safe clinical application is the availability of pure populations for direct cell transplantation or tissue engineering as well as the immunological compatibility of the transplanted cells. The expression of human surface markers under the control of cell type specific promoters represents a promising approach for the selection of cardiomyocytes and other cell types for therapeutic applications. The first human clinical trial using ES cells will start in the United States this year.

  12. Renal stem cells: fact or science fiction?

    Science.gov (United States)

    McCampbell, Kristen K; Wingert, Rebecca A

    2012-06-01

    The kidney is widely regarded as an organ without regenerative abilities. However, in recent years this dogma has been challenged on the basis of observations of kidney recovery following acute injury, and the identification of renal populations that demonstrate stem cell characteristics in various species. It is currently speculated that the human kidney can regenerate in some contexts, but the mechanisms of renal regeneration remain poorly understood. Numerous controversies surround the potency, behaviour and origins of the cell types that are proposed to perform kidney regeneration. The present review explores the current understanding of renal stem cells and kidney regeneration events, and examines the future challenges in using these insights to create new clinical treatments for kidney disease.

  13. Materials as stem cell regulators

    Science.gov (United States)

    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. Crypt base columnar stem cells in small intestines of mice are radioresistant

    NARCIS (Netherlands)

    Hua, G.; Thin, T.H.; Feldman, R.; Haimovitz-Friedman, A.; Clevers, H.; Fuks, Z.; Kolesnick, R.

    2012-01-01

    BACKGROUND & AIMS: Adult stem cells have been proposed to be quiescent and radiation resistant, repairing DNA double-strand breaks by nonhomologous end joining. However, the population of putative small intestinal stem cells (ISCs) at position +4 from the crypt base contradicts this model, in that

  15. Mature lymphoid malignancies: origin, stem cells, and chronicity

    DEFF Research Database (Denmark)

    Husby, Simon; Grønbæk, Kirsten

    2017-01-01

    after treatment. Lately, the use of next-generation sequencing techniques has revealed essential information on the clonal evolution of lymphoid malignancies. Also, experimental xenograft transplantation point to the possible existence of an ancestral (stem) cell. Such a malignant lymphoid stem cell...... population could potentially evade current therapies and be the cause of chronicity and death in lymphoma patients; however, the evidence is divergent across disease entities and between studies. In this review we present an overview of genetic studies, case reports, and experimental evidence of the source...

  16. Foetal stem cell derivation & characterization for osteogenic lineage

    Directory of Open Access Journals (Sweden)

    A Mangala Gowri

    2013-01-01

    Full Text Available Background & objectives: Mesencymal stem cells (MSCs derived from foetal tissues present a multipotent progenitor cell source for application in tissue engineering and regenerative medicine. The present study was carried out to derive foetal mesenchymal stem cells from ovine source and analyze their differentiation to osteogenic linage to serve as an animal model to predict human applications. Methods: Isolation and culture of sheep foetal bone marrow cells were done and uniform clonally derived MSC population was collected. The cells were characterized using cytochemical, immunophenotyping, biochemical and molecular analyses. The cells with defined characteristics were differentiated into osteogenic lineages and analysis for differentiated cell types was done. The cells were analyzed for cell surface marker expression and the gene expression in undifferentiated and differentiated osteoblast was checked by reverse transcriptase PCR (RT PCR analysis and confirmed by sequencing using genetic analyzer. Results: Ovine foetal samples were processed to obtain mononuclear (MNC cells which on culture showed spindle morphology, a characteristic oval body with the flattened ends. MSC population CD45 - /CD14 - was cultured by limiting dilution to arrive at uniform spindle morphology cells and colony forming units. The cells were shown to be positive for surface markers such as CD44, CD54, integrinβ1, and intracellular collagen type I/III and fibronectin. The osteogenically induced MSCs were analyzed for alkaline phosphatase (ALP activity and mineral deposition. The undifferentiated MSCs expressed RAB3B, candidate marker for stemness in MSCs. The osteogenically induced and uninduced MSCs expressed collagen type I and MMP13 gene in osteogenic induced cells. Interpretation & conclusions: The protocol for isolation of ovine foetal bone marrow derived MSCs was simple to perform, and the cultural method of obtaining pure spindle morphology cells was established

  17. The novel AML stem cell associated antigen CLL-1 aids in discrimination between normal and leukemic stem cells.

    Science.gov (United States)

    van Rhenen, Anna; van Dongen, Guus A M S; Kelder, Angèle; Rombouts, Elwin J; Feller, Nicole; Moshaver, Bijan; Stigter-van Walsum, Marijke; Zweegman, Sonja; Ossenkoppele, Gert J; Jan Schuurhuis, Gerrit

    2007-10-01

    In CD34(+) acute myeloid leukemia (AML), the malignant stem cells reside in the CD38(-) compartment. We have shown before that the frequency of such CD34(+)CD38(-) cells at diagnosis correlates with minimal residual disease (MRD) frequency after chemotherapy and with survival. Specific targeting of CD34(+)CD38(-) cells might thus offer therapeutic options. Previously, we found that C-type lectin-like molecule-1 (CLL-1) has high expression on the whole blast compartment in the majority of AML cases. We now show that CLL-1 expression is also present on the CD34(+)CD38(-) stem- cell compartment in AML (77/89 patients). The CD34(+)CLL-1(+) population, containing the CD34(+)CD38(-)CLL-1(+) cells, does engraft in nonobese diabetic/severe combined immunodeficiency (NOD/SCID) mice with outgrowth to CLL-1(+) blasts. CLL-1 expression was not different between diagnosis and relapse (n = 9). In remission, both CLL-1(-) normal and CLL-1(+) malignant CD34(+)CD38(-) cells were present. A high CLL-1(+) fraction was associated with quick relapse. CLL-1 expression is completely absent both on CD34(+)CD38(-) cells in normal (n = 11) and in regenerating bone marrow controls (n = 6). This AML stem-cell specificity of the anti-CLL-1 antibody under all conditions of disease and the leukemia-initiating properties of CD34(+)CLL-1(+) cells indicate that anti-CLL-1 antibody enables both AML-specific stem-cell detection and possibly antigen-targeting in future.

  18. Inflammatory Human Umbilical Cord-Derived Mesenchymal Stem Cells Promote Stem Cell-Like Characteristics of Cancer Cells in an IL-1β-Dependent Manner

    Directory of Open Access Journals (Sweden)

    Xiaohe Luo

    2018-01-01

    Full Text Available To ensure the safety of clinical applications of MSCs, thorough understanding of their impacts on tumor initiation and progression is essential. Here, to further explore the complex dialog between MSCs and tumor cells, umbilical cord-derived mesenchymal stem cells (UC-MSCs were employed to be cocultured with either breast or ovarian cancer cells. Though having no obvious influence on proliferation or apoptosis, UC-MSCs exerted intense stem cell-like properties promoting effects on both cancer models. Cocultured cancer cells showed enriched side population, enhanced sphere formation ability, and upregulated pluripotency-associated stem cell markers. Human cytokine array and real-time PCR revealed a panel of MSC-derived prostemness cytokines CCL2, CXCL1, IL-8, and IL-6 which were induced upon coculturing. We further revealed IL-1β, a well-characterized proinflammatory cytokine, to be the inducer of these prostemness cytokines, which was generated from inflammatory UC-MSCs in an autocrine manner. Additionally, with introduction of IL-1RA (an IL-1 receptor antagonist into the coculturing system, the stem cell-like characteristics promoting effects of inflammatory UC-MSCs were partially blocked. Taken together, these findings suggest that transduced inflammatory MSCs work as a major source of IL-1β in tumor microenvironment and initiate the formation of prostemness niche via regulating their secretome in an IL-1β-dependent manner.

  19. Dental pulp stem cells

    DEFF Research Database (Denmark)

    Ashri, N. Y.; Ajlan, S. A.; Aldahmash, Abdullah M.

    2015-01-01

    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...... an updated review on dental pulp stem cells and their applications in periodontal regeneration, in combination with different scaffolds and growth factors....

  20. Oral epithelial stem cells – implications in normal development and cancer metastasis

    Science.gov (United States)

    Papagerakis, Silvana; Pannone, Giuseppe; Zheng, Li; About, Imad; Taqi, Nawar; Nguyen, Nghia P.T.; Matossian, Margarite; McAlpin, Blake; Santoro, Angela; McHugh, Jonathan; Prince, Mark E.; Papagerakis, Petros

    2014-01-01

    Oral mucosa is continuously exposed to environmental forces and has to be constantly renewed. Accordingly, the oral mucosa epithelium contains a large reservoir of epithelial stem cells necessary for tissue homeostasis. Despite considerable scientific advances in stem cell behavior in a number of tissues, fewer studies have been devoted to the stem cells in the oral epithelium. Most of oral mucosa stem cells studies are focused on identifying cancer stem cells (CSC) in oral squamous cell carcinomas (OSCCs) among other head and neck cancers. OSCCs are the most prevalent epithelial tumors of the head and neck region, marked by their aggressiveness and invasiveness. Due to their highly tumorigenic properties, it has been suggested that CSC may be the critical population of cancer cells in the development of OSCC metastasis. This review presents a brief overview of epithelium stem cells with implications in oral health, and the clinical implications of the CSC concept in OSCC metastatic dissemination. PMID:24803391

  1. Stem Cell Therapy for Erectile Dysfunction.

    Science.gov (United States)

    Matz, Ethan L; Terlecki, Ryan; Zhang, Yuanyuan; Jackson, John; Atala, Anthony

    2018-04-06

    The prevalence of erectile dysfunction (ED) is substantial and continues to rise. Current therapeutics for ED consist of oral medications, intracavernosal injections, vacuum erection devices, and penile implants. While such options may manage the disease state, none of these modalities, however, restore function. Stem cell therapy has been evaluated for erectile restoration in animal models. These cells have been derived from multiple tissues, have varied potential, and may function via local engraftment or paracrine signaling. Bone marrow-derived stem cells (BMSC) and adipose-derived stem cells (ASC) have both been used in these models with noteworthy effects. Herein, we will review the pathophysiology of ED, animal models, current and novel stem-cell based therapeutics, clinical trials and areas for future research. The relevant literature and contemporary data using keywords, "stem cells and erectile dysfunction" was reviewed. Examination of evidence supporting the association between erectile dysfunction and adipose derived stem cells, bone marrow derived stem cells, placental stem cells, urine stem cells and stem cell therapy respectively. Placental-derived stem cells and urine-derived stem cells possess many similar properties as BMSC and ASC, but the methods of acquisition are favorable. Human clinical trials have already demonstrated successful use of stem cells for improvement of erectile function. The future of stem cell research is constantly being evaluated, although, the evidence suggests a place for stem cells in erectile dysfunction therapeutics. Matz EL, Terlecki R, Zhang Y, et al. Stem Cell Therapy for Erectile Dysfunction. Sex Med Rev 2018;XX:XXX-XXX. Copyright © 2018 International Society for Sexual Medicine. Published by Elsevier Inc. All rights reserved.

  2. Biomaterial-stem cell interactions and their impact on stem cell response

    NARCIS (Netherlands)

    Oziemlak-Schaap, Aneta M.; Kuhn, Philipp T.; van Kooten, Theo G.; van Rijn, Patrick

    2014-01-01

    In this review, current research in the field of biomaterial properties for directing stem cells are discussed and placed in a critical perspective. Regenerative medicine, in which stem cells play a crucial role, has become an interdisciplinary field between cell biology and materials science. New

  3. Functional vascular smooth muscle cells derived from human induced pluripotent stem cells via mesenchymal stem cell intermediates

    Science.gov (United States)

    Bajpai, Vivek K.; Mistriotis, Panagiotis; Loh, Yuin-Han; Daley, George Q.; Andreadis, Stelios T.

    2012-01-01

    Aims Smooth muscle cells (SMC) play an important role in vascular homeostasis and disease. Although adult mesenchymal stem cells (MSC) have been used as a source of contractile SMC, they suffer from limited proliferation potential and culture senescence, particularly when originating from older donors. By comparison, human induced pluripotent stem cells (hiPSC) can provide an unlimited source of functional SMC for autologous cell-based therapies and for creating models of vascular disease. Our goal was to develop an efficient strategy to derive functional, contractile SMC from hiPSC. Methods and results We developed a robust, stage-wise, feeder-free strategy for hiPSC differentiation into functional SMC through an intermediate stage of multipotent MSC, which could be coaxed to differentiate into fat, bone, cartilage, and muscle. At this stage, the cells were highly proliferative and displayed higher clonogenic potential and reduced senescence when compared with parental hair follicle mesenchymal stem cells. In addition, when exposed to differentiation medium, the myogenic proteins such as α-smooth muscle actin, calponin, and myosin heavy chain were significantly upregulated and displayed robust fibrillar organization, suggesting the development of a contractile phenotype. Indeed, tissue constructs prepared from these cells exhibited high levels of contractility in response to receptor- and non-receptor-mediated agonists. Conclusion We developed an efficient stage-wise strategy that enabled hiPSC differentiation into contractile SMC through an intermediate population of clonogenic and multipotent MSC. The high yield of MSC and SMC derivation suggests that our strategy may facilitate an acquisition of the large numbers of cells required for regenerative medicine or for studying vascular disease pathophysiology. PMID:22941255

  4. Embryonic stem cells require Wnt proteins to prevent differentiation to epiblast stem cells

    NARCIS (Netherlands)

    D. ten Berge (Derk); D. Kurek (Dorota); T. Blauwkamp (Tim); W. Koole (Wouter); A. Maas (Alex); E. Eroglu (Elif); R.K. Siu (Ronald); R. Nusse (Roel)

    2011-01-01

    textabstractPluripotent stem cells exist in naive and primed states, epitomized by mouse embryonic stem cells (ESCs) and the developmentally more advanced epiblast stem cells (EpiSCs; ref.). In the naive state of ESCs, the genome has an unusual open conformation and possesses a minimum of repressive

  5. Stem cell test: A practical tool in toxicogenomics

    International Nuclear Information System (INIS)

    Ahuja, Y.R.; Vijayalakshmi, V.; Polasa, K.

    2007-01-01

    During early embryonic development, at blastocyst stage, the embryo has an outer coat of cells and an inner cell mass (ICM). ICM is the reservoir of embryonic stem (ES) cells, which are pluripotent, i.e., have the potential to differentiate into all cell types of the body. Cell lines have been developed from ES cells. In addition, there are embryonic germ (EG) cell lines developed from progenitor germ cells, and embryonic carcinoma (EC) cell lines developed from teratomas. These cell lines are being used for the study of basic and applied aspects in medical therapeutics, and disease management. Another potential of these cell lines is in the field of environmental mutagenesis. In addition to ES cells, there are adult stem cells in and around different organs and tissues of the body. It is now possible to grow pure populations of specific cell types from these adult stem cells. Treating specific cell types with chemical or physical agents and measuring their response offers a shortcut to test the toxicity in various organ systems in the adult organism. For example, to evaluate the genotoxicity of a chemical (e.g., drug or pesticide) or a physical agent (e.g., ionizing radiation or non-ionizing electromagnetic radiation) during embryonic development, a large number of animals are being used. As an alternative, use of stem cell lines would be a feasible proposition. Using stem cell lines, efforts are being made to standardize the protocols, which will not only be useful in testing the toxicity of a chemical or a physical agent, but also in the field of drug development, environmental mutagenesis, biomonitoring and other studies

  6. Ascorbate regulates haematopoietic stem cell function and leukaemogenesis.

    Science.gov (United States)

    Agathocleous, Michalis; Meacham, Corbin E; Burgess, Rebecca J; Piskounova, Elena; Zhao, Zhiyu; Crane, Genevieve M; Cowin, Brianna L; Bruner, Emily; Murphy, Malea M; Chen, Weina; Spangrude, Gerald J; Hu, Zeping; DeBerardinis, Ralph J; Morrison, Sean J

    2017-09-28

    Stem-cell fate can be influenced by metabolite levels in culture, but it is not known whether physiological variations in metabolite levels in normal tissues regulate stem-cell function in vivo. Here we describe a metabolomics method for the analysis of rare cell populations isolated directly from tissues and use it to compare mouse haematopoietic stem cells (HSCs) to restricted haematopoietic progenitors. Each haematopoietic cell type had a distinct metabolic signature. Human and mouse HSCs had unusually high levels of ascorbate, which decreased with differentiation. Systemic ascorbate depletion in mice increased HSC frequency and function, in part by reducing the function of Tet2, a dioxygenase tumour suppressor. Ascorbate depletion cooperated with Flt3 internal tandem duplication (Flt3 ITD ) leukaemic mutations to accelerate leukaemogenesis, through cell-autonomous and possibly non-cell-autonomous mechanisms, in a manner that was reversed by dietary ascorbate. Ascorbate acted cell-autonomously to negatively regulate HSC function and myelopoiesis through Tet2-dependent and Tet2-independent mechanisms. Ascorbate therefore accumulates within HSCs to promote Tet activity in vivo, limiting HSC frequency and suppressing leukaemogenesis.

  7. Phenotypic characterization of the bone marrow stem cells used in regenerative cellular therapy

    International Nuclear Information System (INIS)

    Macias Abraham, Consuelo; Valle Perez, Lazaro O del; Baganet Cobas, Aymara

    2011-01-01

    Regenerative medicine is a novel therapeutic method with broad potential for the treatment of various illnesses, based on the use of bone marrow (BM) stem cells, whose phenotypic characterization is limited. The paper deals with the expression of different cell membrane markers in mononuclear BM cells from 14 patients who underwent autologous cell therapy, obtained by medullary puncture and mobilization to peripheral blood, with the purpose of characterizing the different types of cells present in that heterogeneous cellular population and identifying the adhesion molecules involved in their adhesion. A greater presence was observed of adherent stem cells from the marrow stroma in mononuclear cells obtained directly from the BM; a larger population of CD90 +c ells in mononuclear cells from CD34 -/ CD45 -p eripheral blood with a high expression of molecules CD44 and CD62L, which suggests a greater presence of mesenchymal stem cells (MSC) in mobilized cells from the marrow stroma. The higher levels of CD34 +c ells in peripheral blood stem cells with a low expression of molecules CD117 -a nd DR -s uggests the presence of hematopoietic stem cells, hemangioblasts and progenitor endothelial cells mobilized to peripheral circulation. It was found that mononuclear cells from both the BM and peripheral blood show a high presence of stem cells with expression of adhesion molecule CD44 (MMC marker), probably involved in their migration, settling and differentiation

  8. c-Kit-positive cardiac stem cells nested in hypoxic niches are activated by stem cell factor reversing the aging myopathy.

    Science.gov (United States)

    Sanada, Fumihiro; Kim, Junghyun; Czarna, Anna; Chan, Noel Yan-Ki; Signore, Sergio; Ogórek, Barbara; Isobe, Kazuya; Wybieralska, Ewa; Borghetti, Giulia; Pesapane, Ada; Sorrentino, Andrea; Mangano, Emily; Cappetta, Donato; Mangiaracina, Chiara; Ricciardi, Mario; Cimini, Maria; Ifedigbo, Emeka; Perrella, Mark A; Goichberg, Polina; Choi, Augustine M; Kajstura, Jan; Hosoda, Toru; Rota, Marcello; Anversa, Piero; Leri, Annarosa

    2014-01-03

    Hypoxia favors stem cell quiescence, whereas normoxia is required for stem cell activation, but whether cardiac stem cell (CSC) function is regulated by the hypoxic/normoxic state of the cell is currently unknown. A balance between hypoxic and normoxic CSCs may be present in the young heart, although this homeostatic control may be disrupted with aging. Defects in tissue oxygenation occur in the old myocardium, and this phenomenon may expand the pool of hypoxic CSCs, which are no longer involved in myocyte renewal. Here, we show that the senescent heart is characterized by an increased number of quiescent CSCs with intact telomeres that cannot re-enter the cell cycle and form a differentiated progeny. Conversely, myocyte replacement is controlled only by frequently dividing CSCs with shortened telomeres; these CSCs generate a myocyte population that is chronologically young but phenotypically old. Telomere dysfunction dictates their actual age and mechanical behavior. However, the residual subset of quiescent young CSCs can be stimulated in situ by stem cell factor reversing the aging myopathy. Our findings support the notion that strategies targeting CSC activation and growth interfere with the manifestations of myocardial aging in an animal model. Although caution has to be exercised in the translation of animal studies to human beings, our data strongly suggest that a pool of functionally competent CSCs persists in the senescent heart and that this stem cell compartment can promote myocyte regeneration effectively, partly correcting the aging myopathy.

  9. TOPICAL REVIEW: Stem cells engineering for cell-based therapy

    Science.gov (United States)

    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.

  10. Stem Cell Niches in Glioblastoma: A Neuropathological View

    Directory of Open Access Journals (Sweden)

    Davide Schiffer

    2014-01-01

    Full Text Available Glioblastoma (GBM stem cells (GSCs, responsible for tumor growth, recurrence, and resistance to therapies, are considered the real therapeutic target, if they had no molecular mechanisms of resistance, in comparison with the mass of more differentiated cells which are insensitive to therapies just because of being differentiated and nonproliferating. GSCs occur in tumor niches where both stemness status and angiogenesis are conditioned by the microenvironment. In both perivascular and perinecrotic niches, hypoxia plays a fundamental role. Fifteen glioblastomas have been studied by immunohistochemistry and immunofluorescence for stemness and differentiation antigens. It has been found that circumscribed necroses develop inside hyperproliferating areas that are characterized by high expression of stemness antigens. Necrosis developed inside them because of the imbalance between the proliferation of tumor cells and endothelial cells; it reduces the number of GSCs to a thin ring around the former hyperproliferating area. The perinecrotic GSCs are nothing else that the survivors remnants of those populating hyperproliferating areas. In the tumor, GSCs coincide with malignant areas so that the need to detect where they are located is not so urgent.

  11. Road for understanding cancer stem cells

    DEFF Research Database (Denmark)

    Serakinci, Nedime; Erzik, Can

    2007-01-01

    There is increasing evidence suggesting that stem cells are susceptive to carcinogenesis and, consequently, can be the origin of many cancers. Recently, the neoplastic potential of stem cells has been supported by many groups showing the existence of subpopulations with stem cell characteristics...... in tumor biopsies such as brain and breast. Evidence supporting the cancer stem cell hypothesis has gained impact due to progress in stem cell biology and development of new models to validate the self-renewal potential of stem cells. Recent evidence on the possible identification of cancer stem cells may...... offer an opportunity to use these cells as future therapeutic targets. Therefore, model systems in this field have become very important and useful. This review will focus on the state of knowledge on cancer stem cell research, including cell line models for cancer stem cells. The latter will, as models...

  12. The Neurovascular Properties of Dental Stem Cells and Their Importance in Dental Tissue Engineering

    Science.gov (United States)

    Ratajczak, Jessica; Bronckaers, Annelies; Dillen, Yörg; Gervois, Pascal; Vangansewinkel, Tim; Driesen, Ronald B.; Wolfs, Esther; Lambrichts, Ivo

    2016-01-01

    Within the field of tissue engineering, natural tissues are reconstructed by combining growth factors, stem cells, and different biomaterials to serve as a scaffold for novel tissue growth. As adequate vascularization and innervation are essential components for the viability of regenerated tissues, there is a high need for easily accessible stem cells that are capable of supporting these functions. Within the human tooth and its surrounding tissues, different stem cell populations can be distinguished, such as dental pulp stem cells, stem cells from human deciduous teeth, stem cells from the apical papilla, dental follicle stem cells, and periodontal ligament stem cells. Given their straightforward and relatively easy isolation from extracted third molars, dental stem cells (DSCs) have become an attractive source of mesenchymal-like stem cells. Over the past decade, there have been numerous studies supporting the angiogenic, neuroprotective, and neurotrophic effects of the DSC secretome. Together with their ability to differentiate into endothelial cells and neural cell types, this makes DSCs suitable candidates for dental tissue engineering and nerve injury repair. PMID:27688777

  13. The Neurovascular Properties of Dental Stem Cells and Their Importance in Dental Tissue Engineering

    Directory of Open Access Journals (Sweden)

    Jessica Ratajczak

    2016-01-01

    Full Text Available Within the field of tissue engineering, natural tissues are reconstructed by combining growth factors, stem cells, and different biomaterials to serve as a scaffold for novel tissue growth. As adequate vascularization and innervation are essential components for the viability of regenerated tissues, there is a high need for easily accessible stem cells that are capable of supporting these functions. Within the human tooth and its surrounding tissues, different stem cell populations can be distinguished, such as dental pulp stem cells, stem cells from human deciduous teeth, stem cells from the apical papilla, dental follicle stem cells, and periodontal ligament stem cells. Given their straightforward and relatively easy isolation from extracted third molars, dental stem cells (DSCs have become an attractive source of mesenchymal-like stem cells. Over the past decade, there have been numerous studies supporting the angiogenic, neuroprotective, and neurotrophic effects of the DSC secretome. Together with their ability to differentiate into endothelial cells and neural cell types, this makes DSCs suitable candidates for dental tissue engineering and nerve injury repair.

  14. Cancer stem cells in solid tumors: is 'evading apoptosis' a hallmark of cancer?

    Science.gov (United States)

    Enderling, Heiko; Hahnfeldt, Philip

    2011-08-01

    Conventional wisdom has long held that once a cancer cell has developed it will inevitably progress to clinical disease. Updating this paradigm, it has more recently become apparent that the tumor interacts with its microenvironment and that some environmental bottlenecks, such as the angiogenic switch, must be overcome for the tumor to progress. In parallel, attraction has been drawn to the concept that there is a minority population of cells - the cancer stem cells - bestowed with the exclusive ability to self-renew and regenerate the tumor. With therapeutic targeting issues at stake, much attention has shifted to the identification of cancer stem cells, the thinking being that the remaining non-stem population, already fated to die, will play a negligible role in tumor development. In fact, the newly appreciated importance of intercellular interactions in cancer development also extends in a unique and unexpected way to interactions between the stem and non-stem compartments of the tumor. Here we discuss recent findings drawn from a hybrid mathematical-cellular automaton model that simulates growth of a heterogeneous solid tumor comprised of cancer stem cells and non-stem cancer cells. The model shows how the introduction of cell fate heterogeneity paradoxically influences the tumor growth dynamic in response to apoptosis, to reveal yet another bottleneck to tumor progression potentially exploitable for disease control. Copyright © 2011 Elsevier Ltd. All rights reserved.

  15. Human Uterine Leiomyoma Stem/Progenitor Cells Expressing CD34 and CD49b Initiate Tumors In Vivo

    Science.gov (United States)

    Ono, Masanori; Moravek, Molly B.; Coon, John S.; Navarro, Antonia; Monsivais, Diana; Dyson, Matthew T.; Druschitz, Stacy A.; Malpani, Saurabh S.; Serna, Vanida A.; Qiang, Wenan; Chakravarti, Debabrata; Kim, J. Julie; Bulun, Serdar E.

    2015-01-01

    Context: Uterine leiomyoma is the most common benign tumor in reproductive-age women. Using a dye-exclusion technique, we previously identified a side population of leiomyoma cells exhibiting stem cell characteristics. However, unless mixed with mature myometrial cells, these leiomyoma side population cells did not survive or grow well in vitro or in vivo. Objective: The objective of this study was to identify cell surface markers to isolate leiomyoma stem/progenitor cells. Design: Real-time PCR screening was used to identify cell surface markers preferentially expressed in leiomyoma side population cells. In vitro colony-formation assay and in vivo tumor-regeneration assay were used to demonstrate functions of leiomyoma stem/progenitor cells. Results: We found significantly elevated CD49b and CD34 gene expression in side population cells compared with main population cells. Leiomyoma cells were sorted into three populations based on the expression of CD34 and CD49b: CD34+/CD49b+, CD34+/CD49b−, and CD34−/CD49b− cells, with the majority of the side population cells residing in the CD34+/CD49b+ fraction. Of these populations, CD34+/CD49b+ cells expressed the lowest levels of estrogen receptor-α, progesterone receptor, and α-smooth muscle actin, but the highest levels of KLF4, NANOG, SOX2, and OCT4, confirming their more undifferentiated status. The stemness of CD34+/CD49b+ cells was also demonstrated by their strongest in vitro colony-formation capacity and in vivo tumor-regeneration ability. Conclusions: CD34 and CD49b are cell surface markers that can be used to enrich a subpopulation of leiomyoma cells possessing stem/progenitor cell properties; this technique will accelerate efforts to develop new therapies for uterine leiomyoma. PMID:25658015

  16. When stem cells grow old: phenotypes and mechanisms of stem cell aging

    Science.gov (United States)

    Schultz, Michael B.; Sinclair, David A.

    2016-01-01

    All multicellular organisms undergo a decline in tissue and organ function as they age. An attractive theory is that a loss in stem cell number and/or activity over time causes this decline. In accordance with this theory, aging phenotypes have been described for stem cells of multiple tissues, including those of the hematopoietic system, intestine, muscle, brain, skin and germline. Here, we discuss recent advances in our understanding of why adult stem cells age and how this aging impacts diseases and lifespan. With this increased understanding, it is feasible to design and test interventions that delay stem cell aging and improve both health and lifespan. PMID:26732838

  17. Stem Cell Transplant

    Science.gov (United States)

    ... Graft-versus-host disease: A potential risk when stem cells come from donors If you receive a transplant ... medications and blood products into your body. Collecting stem cells for transplant If a transplant using your own ...

  18. Embryonic Stem Cell Proteins and MicroRNAs in the Etiology of Germ Cell Cancer

    NARCIS (Netherlands)

    R. Eini (Ronak)

    2013-01-01

    textabstractIn the early 1980s, a population of unique cells was isolated from the inner cell mass (ICM) of the mouse pre-implantation embryo named embryonic stem (ES) cells. These cells were generated by removing the ICM from pre-implantation blastocysts. The resulting cells were found to be

  19. Endogenous Fluorescence Signatures in Living Pluripotent Stem Cells Change with Loss of Potency

    Science.gov (United States)

    Squirrell, Jayne M.; Fong, Jimmy J.; Ariza, Carlos A.; Mael, Amber; Meyer, Kassondra; Shevde, Nirupama K.; Roopra, Avtar; Lyons, Gary E.; Kamp, Timothy J.; Eliceiri, Kevin W.; Ogle, Brenda M.

    2012-01-01

    The therapeutic potential of stem cells is limited by the non-uniformity of their phenotypic state. Thus it would be advantageous to noninvasively monitor stem cell status. Driven by this challenge, we employed multidimensional multiphoton microscopy to quantify changes in endogenous fluorescence occurring with pluripotent stem cell differentiation. We found that global and cellular-scale fluorescence lifetime of human embryonic stem cells (hESC) and murine embryonic stem cells (mESC) consistently decreased with differentiation. Less consistent were trends in endogenous fluorescence intensity with differentiation, suggesting intensity is more readily impacted by nuances of species and scale of analysis. What emerges is a practical and accessible approach to evaluate, and ultimately enrich, living stem cell populations based on changes in metabolism that could be exploited for both research and clinical applications. PMID:22952742

  20. Skin Stem Cells in Skin Cell Therapy

    Directory of Open Access Journals (Sweden)

    Mollapour Sisakht

    2015-12-01

    Full Text Available Context Preclinical and clinical research has shown that stem cell therapy is a promising therapeutic option for many diseases. This article describes skin stem cells sources and their therapeutic applications. Evidence Acquisition Compared with conventional methods, cell therapy reduces the surgical burden for patients because it is simple and less time-consuming. Skin cell therapy has been developed for variety of diseases. By isolation of the skin stem cell from the niche, in vitro expansion and transplantation of cells offers a surprising healing capacity profile. Results Stem cells located in skin cells have shown interesting properties such as plasticity, transdifferentiation, and specificity. Mesenchymal cells of the dermis, hypodermis, and other sources are currently being investigated to promote regeneration. Conclusions Because skin stem cells are highly accessible from autologous sources and their immunological profile is unique, they are ideal for therapeutic approaches. Optimization of administrative routes requires more investigation own to the lack of a standard protocol.

  1. SALL4, a stem cell factor, affects the side population by regulation of the ATP-binding cassette drug transport genes.

    Directory of Open Access Journals (Sweden)

    Ha-Won Jeong

    2011-04-01

    Full Text Available Our previous work shows that the stem cell factor SALL4 plays a central role in embryonic and leukemic stem cells. In this study, we report that SALL4 expression was higher in drug resistant primary acute myeloid leukemic patients than those from drug-responsive cases. In addition, while overexpression of SALL4 led to drug resistance in cell lines, cells with decreased SALL4 expression were more sensitive to drug treatments than the parental cells. This led to our investigation of the implication of SALL4 in drug resistance and its role in side population (SP cancer stem cells. SALL4 expression was higher in SP cells compared to non-SP cells by 2-4 fold in various malignant hematopoietic cell lines. Knocking down of SALL4 in isolated SP cells resulted in a reduction of SP cells, indicating that SALL4 is required for their self-renewal. The SP phenotype is known to be mediated by members of the ATP-binding cassette (ABC drug transport protein family, such as ABCG2 and ABCA3. Using chromatin-immunoprecipitation (ChIP, quantitative reverse transcription polymerase chain reaction (qRT-PCR and electrophoretic mobility shift assay(EMSA, we demonstrated that SALL4 was able to bind to the promoter region of ABCA3 and activate its expression while regulating the expression of ABCG2 indirectly. Furthermore, SALL4 expression was positively correlated to those of ABCG2 and ABCA3 in primary leukemic patient samples. Taken together, our results suggest a novel role for SALL4 in drug sensitivity, at least in part through the maintenance of SP cells, and therefore may be responsible for drug-resistance in leukemia. We are the first to demonstrate a direct link between stem cell factor SALL4, SP and drug resistance in leukemia.

  2. Stem cell dynamics in the hair follicle niche

    Science.gov (United States)

    Rompolas, Panteleimon; Greco, Valentina

    2014-01-01

    Hair follicles are skin appendages of the mammalian skin that have the ability to periodically and stereotypically regenerate in order to continuously produce new hair over our lifetime. The ability of the hair follicle to regenerate is due to the presence of stem cells that along with other cell populations and non-cellular components, including molecular signals and extracellular material, make up a niche microenvironment. Mounting evidence suggests that the niche is critical for regulating stem cell behavior and thus the process of regeneration. Here we review the literature concerning past and current studies that have utilized mouse genetic models, combined with other approaches to dissect the molecular and cellular composition of the hair follicle niche. We also discuss our current understanding of how stem cells operate within the niche during the process of tissue regeneration and the factors that regulate their behavior. PMID:24361866

  3. CellNet: Network Biology Applied to Stem Cell Engineering

    Science.gov (United States)

    Cahan, Patrick; Li, Hu; Morris, Samantha A.; da Rocha, Edroaldo Lummertz; Daley, George Q.; Collins, James J.

    2014-01-01

    SUMMARY Somatic cell reprogramming, directed differentiation of pluripotent stem cells, and direct conversions between differentiated cell lineages represent powerful approaches to engineer cells for research and regenerative medicine. We have developed CellNet, a network biology platform that more accurately assesses the fidelity of cellular engineering than existing methodologies and generates hypotheses for improving cell derivations. Analyzing expression data from 56 published reports, we found that cells derived via directed differentiation more closely resemble their in vivo counterparts than products of direct conversion, as reflected by the establishment of target cell-type gene regulatory networks (GRNs). Furthermore, we discovered that directly converted cells fail to adequately silence expression programs of the starting population, and that the establishment of unintended GRNs is common to virtually every cellular engineering paradigm. CellNet provides a platform for quantifying how closely engineered cell populations resemble their target cell type and a rational strategy to guide enhanced cellular engineering. PMID:25126793

  4. CellNet: network biology applied to stem cell engineering.

    Science.gov (United States)

    Cahan, Patrick; Li, Hu; Morris, Samantha A; Lummertz da Rocha, Edroaldo; Daley, George Q; Collins, James J

    2014-08-14

    Somatic cell reprogramming, directed differentiation of pluripotent stem cells, and direct conversions between differentiated cell lineages represent powerful approaches to engineer cells for research and regenerative medicine. We have developed CellNet, a network biology platform that more accurately assesses the fidelity of cellular engineering than existing methodologies and generates hypotheses for improving cell derivations. Analyzing expression data from 56 published reports, we found that cells derived via directed differentiation more closely resemble their in vivo counterparts than products of direct conversion, as reflected by the establishment of target cell-type gene regulatory networks (GRNs). Furthermore, we discovered that directly converted cells fail to adequately silence expression programs of the starting population and that the establishment of unintended GRNs is common to virtually every cellular engineering paradigm. CellNet provides a platform for quantifying how closely engineered cell populations resemble their target cell type and a rational strategy to guide enhanced cellular engineering. Copyright © 2014 Elsevier Inc. All rights reserved.

  5. Isolation, culture, characterization, and osteogenic differentiation of canine endometrial mesenchymal stem cell

    Directory of Open Access Journals (Sweden)

    A. K. Sahoo

    2017-12-01

    Full Text Available Aim: In this study, the canine endometrium tissue is characterized for its stem cell properties such as adherence to tissue culture plate (plasticity, short population doubling time, serial clonal passaging, long-term culturing properties, stem cell marker expression, and multilineage differentiation potential. Materials and Methods: The present work describes a novel isolation protocol for obtaining mesenchymal stem cells from the uterine endometrium and is compared with cells derived from umbilical cord matrix as a positive control. These cells are clonogenic, can undergo several population doublings in vitro, and can be differentiated to the osteocytes in mature mesenchymal tissues when grown in osteogenic differentiation media as detected by Alizarin Red-S staining. Results: It is reported for the first time that the cells derived from the canine endometrium (e-multipotent stem cells [MSCs] were able to differentiate into a heterologous cell type: Osteocytes, thus demonstrating the presence of MSCs. Thus, the endometrium may be told as a potential source of MSCs which can be used for various therapeutic purposes. Conclusion: The endometrium can be used as a potential source of MSCs, which can be used for various therapeutic purposes.

  6. Slow-cycling stem cells in hydra contribute to head regeneration

    Directory of Open Access Journals (Sweden)

    Niraimathi Govindasamy

    2014-11-01

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

  7. Stem cells and chronic wound healing: state of the art

    Directory of Open Access Journals (Sweden)

    Leavitt T

    2016-03-01

    Full Text Available Tripp Leavitt, Michael S Hu, Clement D Marshall, Leandra A Barnes, Michael T Longaker, H Peter Lorenz Hagey Laboratory for Pediatric Regenerative Medicine, Division of Plastic Surgery, Department of Surgery, Stanford University School of Medicine, Stanford, CA, USA Abstract: Currently available treatments for chronic wounds are inadequate. A clearly effective therapy does not exist, and treatment is often supportive. This is largely because the cellular and molecular processes underlying failure of wound repair are still poorly understood. With an increase in comorbidities, such as diabetes and vascular disease, as well as an aging population, the incidence of these intractable wounds is expected to rise. As such, chronic wounds, which are already costly, are rapidly growing as a tremendous burden to the health-care system. Stem cells have garnered much interest as a therapy for chronic wounds due to their inherent ability to differentiate into multiple lineages and promote regeneration. Herein, we discuss the types of stem cells used for chronic wound therapy, as well as the proposed means by which they do so. In particular, we highlight mesenchymal stem cells (including adipose-derived stem cells, endothelial progenitor cells, and induced pluripotent stem cells. We include the results of recent in vitro and in vivo studies in both animal models and human clinical trials. Finally, we discuss the current studies to improve stem cell therapies and the limitations of stem cell-based therapeutics. Stem cells promise improved therapies for healing chronic wounds, but further studies that are well-designed with standardized protocols are necessary for fruition. Keywords: stem cells, chronic wounds, cell therapy, wound healing

  8. Nature of leukemic stem cells in murine myelogenous leukemia

    International Nuclear Information System (INIS)

    Yoshida, K.; Nemoto, K.; Nishimura, M.; Hayata, I.; Inoue, T.; Seki, M.

    1986-01-01

    We investigated the nature of myelogenous leukemic stem cells in mice. L-8057, a megakaryoblastic leukemia cell line used in this study, produces in vivo and in vitro colonies. By means of typical chromosomal aberrations in L-8057, one can conveniently detect the origin of the cells in each colony derived from a leukemic stem cell. Direct evidence of whether cells from each colony had leukemogenicity in recipient mice was successfully obtained by the colony transplantation assay. Both leukemic colony-forming unit-spleen (L-CFU-s) and leukemic colony-forming unit-culture (L-CFU-c) in L-8057 may have belonged to the same differentiating stage in the stem cells because of their similar radiosensitivity, although some parts of the L-CFU of L-8057 seemed to have lost their capability to regenerate L-CFU-s when the cells were plated in dishes. This leukemic stem cell preserves high self-renewal ability in vitro after 10 passages. In addition, in vitro colony formation by this leukemic cell during the above course of serial passages did not require any additional exogenous stimulators. The same sort of trials have been made on other types of leukemias. Leukemic stem cells showed remarkable variety in their response to stimulating factors and in their self-renewal activity, which suggests that they may have consisted of heterogeneous populations

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

    International Nuclear Information System (INIS)

    Varga, Nóra; Veréb, Zoltán; Rajnavölgyi, Éva; Német, Katalin; Uher, Ferenc; Sarkadi, Balázs; Apáti, Ágota

    2011-01-01

    Highlights: ► MSC like cells were derived from hESC by a simple and reproducible method. ► Differentiation and immunosuppressive features of MSCl cells were similar to bmMSC. ► 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.

  10. Stem Cells and Aging.

    Science.gov (United States)

    Koliakos, George

    2017-02-01

    The article is a presentation at the 4th Conference of ESAAM, which took place on October 30-31, 2015, in Athens, Greece. Its purpose was not to cover all aspects of cellular aging but to share with the audience of the Conference, in a 15-minute presentation, current knowledge about the rejuvenating and repairing somatic stem cells that are distinct from other stem cell types (such as embryonic or induced pluripotent stem cells), emphasize that our body in old age cannot take advantage of these rejuvenating cells, and provide some examples of novel experimental stem cell applications in the field of rejuvenation and antiaging biomedical research.

  11. Aging and stem cell therapy: AMPK as an applicable pharmacological target for rejuvenation of aged stem cells and achieving higher efficacy in stem cell therapy.

    Science.gov (United States)

    Khorraminejad-Shirazi, Mohammadhossein; Farahmandnia, Mohammad; Kardeh, Bahareh; Estedlal, Alireza; Kardeh, Sina; Monabati, Ahmad

    2017-10-19

    In recent years, tissue regeneration has become a promising field for developing stem cell-based transplantation therapies for human patients. Adult stem cells are affected by the same aging mechanisms that involve somatic cells. One of the mechanisms involved in cellular aging is hyperactivation of mechanistic target of rapamycin complex 1 (mTORC1) and disruption of 5' adenosine monophosphate-activated protein kinase (AMPK). Aging of stem cells results in their impaired regenerative capacity and depletion of stem cell pools in adult tissue, which results in lower efficacy of stem cell therapy. By utilizing an effective therapeutic intervention for aged stem cells, stem cell therapy can become more promising for future application. mTORC1 inhibition is a practical approach to preserve the stem cell pool. In this article, we review the dynamic interaction between sirtuin (silent mating type information regulation 2 homolog) 1, AMPK, and mTORC1. We propose that using AMPK activators such as 5-aminoimidazole-4-carboxamide ribonucleotide, A769662, metformin, and oxidized nicotinamide adenine dinucleotide (NAD + ) are practical ways to be employed for achieving better optimized results in stem cell-based transplantation therapies. Copyright © 2017 King Faisal Specialist Hospital & Research Centre. Published by Elsevier B.V. All rights reserved.

  12. Skin Stem Cell Hypotheses and Long Term Clone Survival - Explored Using Agent-based Modelling

    OpenAIRE

    Li, X.; Upadhyay, A.K.; Bullock, A.J.; Dicolandrea, T.; Xu, J.; Binder, R.L.; Robinson, M.K.; Finlay, D.R.; Mills, K.J.; Bascom, C.C.; Kelling, C.K.; Isfort, R.J.; Haycock, J.W.; MacNeil, S.; Smallwood, R.H.

    2013-01-01

    Epithelial renewal in skin is achieved by the constant turnover and differentiation of keratinocytes. Three popular hypotheses have been proposed to explain basal keratinocyte regeneration and epidermal homeostasis: 1) asymmetric division (stem-transit amplifying cell); 2) populational asymmetry (progenitor cell with stochastic fate); and 3) populational asymmetry with stem cells. In this study, we investigated lineage dynamics using these hypotheses with a 3D agent-based model of the epiderm...

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

    Science.gov (United States)

    Diensthuber, M; Heller, S

    2010-11-01

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

  14. Skin stem cell hypotheses and long term clone survival--explored using agent-based modelling.

    Science.gov (United States)

    Li, X; Upadhyay, A K; Bullock, A J; Dicolandrea, T; Xu, J; Binder, R L; Robinson, M K; Finlay, D R; Mills, K J; Bascom, C C; Kelling, C K; Isfort, R J; Haycock, J W; MacNeil, S; Smallwood, R H

    2013-01-01

    Epithelial renewal in skin is achieved by the constant turnover and differentiation of keratinocytes. Three popular hypotheses have been proposed to explain basal keratinocyte regeneration and epidermal homeostasis: 1) asymmetric division (stem-transit amplifying cell); 2) populational asymmetry (progenitor cell with stochastic fate); and 3) populational asymmetry with stem cells. In this study, we investigated lineage dynamics using these hypotheses with a 3D agent-based model of the epidermis. The model simulated the growth and maintenance of the epidermis over three years. The offspring of each proliferative cell was traced. While all lineages were preserved in asymmetric division, the vast majority were lost when assuming populational asymmetry. The third hypothesis provided the most reliable mechanism for self-renewal by preserving genetic heterogeneity in quiescent stem cells, and also inherent mechanisms for skin ageing and the accumulation of genetic mutation.

  15. Stem Cell Lineages: Between Cell and Organism

    Directory of Open Access Journals (Sweden)

    Melinda Bonnie Fagan

    2017-01-01

    Full Text Available Ontologies of living things are increasingly grounded on the concepts and practices of current life science. Biological development is a process, undergone by living things, which begins with a single cell and (in an important class of cases ends with formation of a multicellular organism. The process of development is thus prima facie central for ideas about biological individuality and organismality. However, recent accounts of these concepts do not engage developmental biology. This paper aims to fill the gap, proposing the lineage view of stem cells as an ontological framework for conceptualizing organismal development. This account is grounded on experimental practices of stem cell research, with emphasis on new techniques for generating biological organization in vitro. On the lineage view, a stem cell is the starting point of a cell lineage with a specific organismal source, time-interval of existence, and ‘tree topology’ of branch-points linking the stem to developmental termini. The concept of ‘enkapsis’ accommodates the cell-organism relation within the lineage view; this hierarchical notion is further explicated by considering the methods and results of stem cell experiments. Results of this examination include a (partial characterization of stem cells’ developmental versatility, and the context-dependence of developmental processes involving stem cells.

  16. Therapeutic targeting of the p53 pathway in cancer stem cells

    Science.gov (United States)

    Prabhu, Varun V.; Allen, Joshua E.; Hong, Bo; Zhang, Shengliang; Cheng, Hairong; El-Deiry, Wafik S.

    2013-01-01

    Introduction Cancer stem cells are a high profile drug target for cancer therapeutics due to their indispensable role in cancer progression, maintenance, and therapeutic resistance. Restoring wild-type p53 function is an attractive new therapeutic approach for the treatment of cancer due to the well-described powerful tumor suppressor function of p53. As emerging evidence intimately links p53 and stem cell biology, this approach also provides an opportunity to target cancer stem cells. Areas covered Therapeutic approaches to restore the function of wild-type p53, cancer and normal stem cell biology in relation to p53, and the downstream effects of p53 on cancer stem cells. Expert opinion The restoration of wild-type p53 function by targeting p53 directly, its interacting proteins, or its family members holds promise as a new class of cancer therapies. This review examines the impact that such therapies may have on normal and cancer stem cells based on the current evidence linking p53 signaling with these populations. PMID:22998602

  17. A novel and generalizable organotypic slice platform to evaluate stem cell potential for targeting pediatric brain tumors

    Directory of Open Access Journals (Sweden)

    Li Shengwen

    2008-05-01

    Full Text Available Abstract Brain tumors are now the leading cause of cancer-related deaths in children under age 15. Malignant gliomas are, for all practical purposes, incurable and new therapeutic approaches are desperately needed. One emerging strategy is to use the tumor tracking capacity inherent in many stem cell populations to deliver therapeutic agents to the brain cancer cells. Current limitations of the stem cell therapy strategy include that stem cells are treated as a single entity and lack of uniform technology is adopted for selection of clinically relevant sub-populations of stem cells. Specifically, therapeutic success relies on the selection of a clinically competent stem cell population based on their capacity of targeting brain tumors. A novel and generalizable organotypic slice platform to evaluate stem cell potential for targeting pediatric brain tumors is proposed to fill the gap in the current work flow of stem cell-based therapy. The organotypic slice platform has advantages of being mimic in vivo model, easier to manipulate to optimize parameters than in vivo models such as rodents and primates. This model serves as a framework to address the discrepancy between anticipated in vivo results and actual in vivo results, a critical barrier to timely progress in the field of the use of stem cells for the treatment of neurological disorders.

  18. Stem cell plasticity.

    Science.gov (United States)

    Lakshmipathy, Uma; Verfaillie, Catherine

    2005-01-01

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

  19. Characterization and comparison of osteoblasts derived from mouse embryonic stem cells and induced pluripotent stem cells

    NARCIS (Netherlands)

    Ma, Ming San; Kannan, Vishnu; de Vries, Anneriek E; Czepiel, Marcin; Wesseling, Evelyn; Balasubramaniyan, Veerakumar; Kuijer, Roelof; Vissink, Arjan; Copray, Sjef; Raghoebar, Gerry

    New developments in stem cell biology offer alternatives for the reconstruction of critical-sized bone defects. One of these developments is the use of induced pluripotent stem (iPS) cells. These stem cells are similar to embryonic stem (ES) cells, but can be generated from adult somatic cells and

  20. When stem cells grow old: phenotypes and mechanisms of stem cell aging.

    Science.gov (United States)

    Schultz, Michael B; Sinclair, David A

    2016-01-01

    All multicellular organisms undergo a decline in tissue and organ function as they age. An attractive theory is that a loss in stem cell number and/or activity over time causes this decline. In accordance with this theory, aging phenotypes have been described for stem cells of multiple tissues, including those of the hematopoietic system, intestine, muscle, brain, skin and germline. Here, we discuss recent advances in our understanding of why adult stem cells age and how this aging impacts diseases and lifespan. With this increased understanding, it is feasible to design and test interventions that delay stem cell aging and improve both health and lifespan. © 2016. Published by The Company of Biologists Ltd.

  1. Molecular heterogeneity in a patient-derived glioblastoma xenoline is regulated by different cancer stem cell populations.

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    Jo Meagan Garner

    Full Text Available Malignant glioblastoma (GBM is a highly aggressive brain tumor with a dismal prognosis and limited therapeutic options. Genomic profiling of GBM samples has identified four molecular subtypes (Proneural, Neural, Classical and Mesenchymal, which may arise from different glioblastoma stem-like cell (GSC populations. We previously showed that adherent cultures of GSCs grown on laminin-coated plates (Ad-GSCs and spheroid cultures of GSCs (Sp-GSCs had high expression of stem cell markers (CD133, Sox2 and Nestin, but low expression of differentiation markers (βIII-tubulin and glial fibrillary acid protein. In the present study, we characterized GBM tumors produced by subcutaneous and intracranial injection of Ad-GSCs and Sp-GSCs isolated from a patient-derived xenoline. Although they formed tumors with identical histological features, gene expression analysis revealed that xenografts of Sp-GSCs had a Classical molecular subtype similar to that of bulk tumor cells. In contrast xenografts of Ad-GSCs expressed a Mesenchymal gene signature. Adherent GSC-derived xenografts had high STAT3 and ANGPTL4 expression, and enrichment for stem cell markers, transcriptional networks and pro-angiogenic markers characteristic of the Mesenchymal subtype. Examination of clinical samples from GBM patients showed that STAT3 expression was directly correlated with ANGPTL4 expression, and that increased expression of these genes correlated with poor patient survival and performance. A pharmacological STAT3 inhibitor abrogated STAT3 binding to the ANGPTL4 promoter and exhibited anticancer activity in vivo. Therefore, Ad-GSCs and Sp-GSCs produced histologically identical tumors with different gene expression patterns, and a STAT3/ANGPTL4 pathway is identified in glioblastoma that may serve as a target for therapeutic intervention.

  2. Brain tumour stem cells: implications for cancer therapy and regenerative medicine.

    Science.gov (United States)

    Sanchez-Martin, Manuel

    2008-09-01

    The cancer relapse and mortality rate suggest that current therapies do not eradicate all malignant cells. Currently, it is accepted that tumorigenesis and organogenesis are similar in many respects, as for example, homeostasis is governed by a distinct sub-population of stem cells in both situations. There is increasing evidence that many types of cancer contain their own stem cells: cancer stem cells (CSC), which are characterized by their self-renewing capacity and differentiation ability. The investigation of solid tumour stem cells has gained momentum particularly in the area of brain tumours. Gliomas are the most common type of primary brain tumours. Nearly two-thirds of gliomas are highly malignant lesions with fast progression and unfortunate prognosis. Despite recent advances, two-year survival for glioblastoma (GBM) with optimal therapy is less than 30%. Even among patients with low-grade gliomas that confer a relatively good prognosis, treatment is almost never curative. Recent studies have demonstrated the existence of a small fraction of glioma cells endowed with features of primitive neural progenitor cells and a tumour-initiating function. In general, this fraction is characterized for forming neurospheres, being endowed with drug resistance properties and often, we can isolate some of them using sorting methods with specific antibodies. The molecular characterization of these stem populations will be critical to developing an effective therapy for these tumours with very dismal prognosis. To achieve this aim, the development of a mouse model which recapitulates the nature of these tumours is essential. This review will focus on glioma stem cell knowledge and discuss future implications in brain cancer therapy and regenerative medicine.

  3. Discovery of the cancer stem cell related determinants of radioresistance

    International Nuclear Information System (INIS)

    Peitzsch, Claudia; Kurth, Ina; Kunz-Schughart, Leoni; Baumann, Michael; Dubrovska, Anna

    2013-01-01

    Tumors are known to be heterogeneous containing a dynamic mixture of phenotypically and functionally different tumor cells. The two concepts attempting to explain the origin of intratumor heterogeneity are the cancer stem cell hypothesis and the clonal evolution model. The stochastic model argues that tumors are biologically homogenous and all cancer cells within the tumor have equal ability to propagate the tumor growth depending on continuing mutations and selective pressure. By contrast, the stem cells model suggests that cancer heterogeneity is due to the hierarchy that originates from a small population of cancer stem cells (CSCs) which are biologically distinct from the bulk tumor and possesses self-renewal, tumorigenic and multilineage potential. Although these two hypotheses have been discussed for a long time as mutually exclusive explanations of tumor heterogeneity, they are easily reconciled serving as a driving force of cancer evolution and diversity. Recent discovery of the cancer cell plasticity and heterogeneity makes the CSC population a moving target that could be hard to track and eradicate. Understanding the signaling mechanisms regulating CSCs during the course of cancer treatment can be indispensable for the optimization of current treatment strategies

  4. Generation of thyroid follicular cells from pluripotent stem cells: Potential for regenerative medicine

    Directory of Open Access Journals (Sweden)

    Will eSewell

    2014-06-01

    Full Text Available Nearly 12 percent of the population in the United States will be afflicted with a thyroid related disorder during their lifetime. Common treatment approaches are tailored to the specific disorder and include surgery, radioactive iodine ablation, antithyroid drugs, thyroid hormone replacement, external beam radiation, and chemotherapy. Regenerative medicine endeavors to combat disease by replacing or regenerating damaged, diseased or dysfunctional body parts. A series of achievements in pluripotent stem cell research have transformed regenerative medicine in many ways by demonstrating repair of a number of body parts in mice, of which, the thyroid has now been inducted into this special group. Seminal work in pluripotent cells, namely embryonic stem cells and induced pluripotent stem cells, have made possible their path to becoming key tools and biological building blocks for cell-based regenerative medicine to combat the gamut of human diseases, including those affecting the thyroid.

  5. What's missing? Discussing stem cell translational research in educational information on stem cell "tourism".

    Science.gov (United States)

    Master, Zubin; Zarzeczny, Amy; Rachul, Christen; Caulfield, Timothy

    2013-01-01

    Stem cell tourism is a growing industry in which patients pursue unproven stem cell therapies for a wide variety of illnesses and conditions. It is a challenging market to regulate due to a number of factors including its international, online, direct-to-consumer approach. Calls to provide education and information to patients, their families, physicians, and the general public about the risks associated with stem cell tourism are mounting. Initial studies examining the perceptions of patients who have pursued stem cell tourism indicate many are highly critical of the research and regulatory systems in their home countries and believe them to be stagnant and unresponsive to patient needs. We suggest that educational material should include an explanation of the translational research process, in addition to other aspects of stem cell tourism, as one means to help promote greater understanding and, ideally, curb patient demand for unproven stem cell interventions. The material provided must stress that strong scientific research is required in order for therapies to be safe and have a greater chance at being effective. Through an analysis of educational material on stem cell tourism and translational stem cell research from patient groups and scientific societies, we describe essential elements that should be conveyed in educational material provided to patients. Although we support the broad dissemination of educational material on stem cell translational research, we also acknowledge that education may simply not be enough to engender patient and public trust in domestic research and regulatory systems. However, promoting patient autonomy by providing good quality information to patients so they can make better informed decisions is valuable in itself, irrespective of whether it serves as an effective deterrent of stem cell tourism. © 2013 American Society of Law, Medicine & Ethics, Inc.

  6. In vitro evaluation of isolation possibility of stem cells from intra oral soft tissue and comparison of them with bone mar-row stem cells

    Directory of Open Access Journals (Sweden)

    P. Torkzaban

    2012-01-01

    Full Text Available Objective: Stem cells are of great interest for regenerating disturbed tissues and organs. These cells are commonly isolated from the bone marrow, but there has been interest in other tissues in the recent years. In this study, we evaluated the possibility of isolation of stem cells from oral connective tissue and investigated their characteristics.Materials and Methods: In this experimental study, sampling from the bone marrow and oral connective tissue of a beagle dog was performed under general anesthesia. Bone marrow stem cell isolation was performed according to the established protocols. The samples obtained from oral soft tissue were broken to small pieces and after adding collagenase I, the samples were incubated for 45 minutes in 37°C. Other processes were similar to the processes which were carried out on bone marrow cells. Then cell properties were compared to evaluate if the cells from the connective tissue were stem cells.Results: The cells from the bone marrow and connective tissue had the same morphology. The result of colony forming unit assay was relatively similar. Population doubling time was similar too. In addition, both cell groups differentiated to osteoblasts in osteogenic media.Conclusion: The cells isolated from the oral connective tissue had the characteristics of stem cells, including fibroblastoid morphology, self renewal properties, high proliferation rate and differentiation potential.

  7. New Monoclonal Antibodies to Defined Cell Surface Proteins on Human Pluripotent Stem Cells.

    Science.gov (United States)

    O'Brien, Carmel M; Chy, Hun S; Zhou, Qi; Blumenfeld, Shiri; Lambshead, Jack W; Liu, Xiaodong; Kie, Joshua; Capaldo, Bianca D; Chung, Tung-Liang; Adams, Timothy E; Phan, Tram; Bentley, John D; McKinstry, William J; Oliva, Karen; McMurrick, Paul J; Wang, Yu-Chieh; Rossello, Fernando J; Lindeman, Geoffrey J; Chen, Di; Jarde, Thierry; Clark, Amander T; Abud, Helen E; Visvader, Jane E; Nefzger, Christian M; Polo, Jose M; Loring, Jeanne F; Laslett, Andrew L

    2017-03-01

    The study and application of human pluripotent stem cells (hPSCs) will be enhanced by the availability of well-characterized monoclonal antibodies (mAbs) detecting cell-surface epitopes. Here, we report generation of seven new mAbs that detect cell surface proteins present on live and fixed human ES cells (hESCs) and human iPS cells (hiPSCs), confirming our previous prediction that these proteins were present on the cell surface of hPSCs. The mAbs all show a high correlation with POU5F1 (OCT4) expression and other hPSC surface markers (TRA-160 and SSEA-4) in hPSC cultures and detect rare OCT4 positive cells in differentiated cell cultures. These mAbs are immunoreactive to cell surface protein epitopes on both primed and naive state hPSCs, providing useful research tools to investigate the cellular mechanisms underlying human pluripotency and states of cellular reprogramming. In addition, we report that subsets of the seven new mAbs are also immunoreactive to human bone marrow-derived mesenchymal stem cells (MSCs), normal human breast subsets and both normal and tumorigenic colorectal cell populations. The mAbs reported here should accelerate the investigation of the nature of pluripotency, and enable development of robust cell separation and tracing technologies to enrich or deplete for hPSCs and other human stem and somatic cell types. Stem Cells 2017;35:626-640. © 2016 The Authors Stem Cells published by Wiley Periodicals, Inc. on behalf of AlphaMed Press.

  8. Bufalin inhibits the differentiation and proliferation of human osteosarcoma cell line hMG63-derived cancer stem cells.

    Science.gov (United States)

    Chang, Yuewen; Zhao, Yongfang; Zhan, Hongsheng; Wei, Xiaoen; Liu, Tianjin; Zheng, Bo

    2014-02-01

    Cancer stem cells (CSCs) play an important role in drug resistance of tumor and are responsible for high recurrence rates. Agents that can suppress the proliferation and differentiation of CSCs would provide new opportunity to fight against tumor recurrence. In this study, we developed a new strategy to enrich CSCs in human osteosarcoma cell line hMG63. Using these CSCs as model, we tested the effect of bufalin, a traditional Chinese medicine, on the proliferation and differentiation of CSCs. hMG63 cells were cultured in poly-HEMA-treated dish and cancer stem cell-specific medium. In this nonadhesive culture system, hMG63 formed spheres, which were then collected and injected into the immunodeficient mice. Cisplatin was administered every 3 days for five times. The enriched xenograft tumors were cultured in cancer stem cell-specific medium again to form tumor spheres. Expression of cancer stem cell markers of these cells was measured by flow cytometry. These cells were then treated with bufalin, and the proliferation and differentiation ability were indicated by the expression level of molecular markers and the formation of sphere again in vitro. We obtained a low CD133+/CD44 cell population with high-level stem cell marker. When treated with bufalin, the sphere could not get attached to the flask and failed to differentiate, which was indicated by the stable expression of stem cell marker CD133 and OCT-4 in the condition permissive to differentiation. Treatment of bufalin also suppressed the single cells isolated from the sphere to form sphere again in the nonadhesive culture system, and a decreased expression of proliferation marker Ki67 was also detected in these cells. Sphere-formed and chemoresistant colon xenograft tumors in immunodeficient mice could enrich cancer stem cell population. Bufalin could inhibit proliferation and differentiation of CSCs.

  9. Biophysical subsets of embryonic stem cells display distinct phenotypic and morphological signatures.

    Directory of Open Access Journals (Sweden)

    Tom Bongiorno

    Full Text Available The highly proliferative and pluripotent characteristics of embryonic stem cells engender great promise for tissue engineering and regenerative medicine, but the rapid identification and isolation of target cell phenotypes remains challenging. Therefore, the objectives of this study were to characterize cell mechanics as a function of differentiation and to employ differences in cell stiffness to select population subsets with distinct mechanical, morphological, and biological properties. Biomechanical analysis with atomic force microscopy revealed that embryonic stem cells stiffened within one day of differentiation induced by leukemia inhibitory factor removal, with a lagging but pronounced change from spherical to spindle-shaped cell morphology. A microfluidic device was then employed to sort a differentially labeled mixture of pluripotent and differentiating cells based on stiffness, resulting in pluripotent cell enrichment in the soft device outlet. Furthermore, sorting an unlabeled population of partially differentiated cells produced a subset of "soft" cells that was enriched for the pluripotent phenotype, as assessed by post-sort characterization of cell mechanics, morphology, and gene expression. The results of this study indicate that intrinsic cell mechanical properties might serve as a basis for efficient, high-throughput, and label-free isolation of pluripotent stem cells, which will facilitate a greater biological understanding of pluripotency and advance the potential of pluripotent stem cell differentiated progeny as cell sources for tissue engineering and regenerative medicine.

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

    Energy Technology Data Exchange (ETDEWEB)

    Varga, Nora [Membrane Research Group of the Hungarian Academy of Sciences, Semmelweis University, Budapest (Hungary); Vereb, Zoltan; Rajnavoelgyi, Eva [Department of Immunology, Medical and Health Science Centre, University of Debrecen, Debrecen (Hungary); Nemet, Katalin; Uher, Ferenc; Sarkadi, Balazs [Membrane Research Group of the Hungarian Academy of Sciences, Semmelweis University, Budapest (Hungary); Apati, Agota, E-mail: apati@kkk.org.hu [Membrane Research Group of the Hungarian Academy of Sciences, Semmelweis University, Budapest (Hungary)

    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.

  11. Non-coding RNAs in Mesenchymal Stem Cell-Derived Extracellular Vesicles: Deciphering Regulatory Roles in Stem Cell Potency, Inflammatory Resolve, and Tissue Regeneration

    Directory of Open Access Journals (Sweden)

    Farah Fatima

    2017-10-01

    Full Text Available Extracellular vesicles (EVs are heterogeneous populations of nano- and micro-sized vesicles secreted by various cell types. There is mounting evidence that EVs have widespread roles in transporting proteins, lipids, and nucleic acids between cells and serve as mediators of intercellular communication. EVs secreted from stem cells could function as paracrine factors, and appear to mimic and recapitulate several features of their secreting cells. EV-mediated transport of regulatory RNAs provides a novel source of trans-regulation between cells. As such, stem cells have evolved unique forms of paracrine mechanisms for recapitulating their potencies with specialized functions by transporting non-coding RNAs (ncRNAs via EVs. This includes the dissemination of stem cell-derived EV-ncRNAs and their regulatory effects elicited in differentiation, self-renewal, pluripotency, and the induction of reparative programs. Here, we summarize and discuss the therapeutic effects of mesenchymal stem cell-derived EV-ncRNAs in the induction of intrinsic regenerative programs elicited through regulating several mechanisms. Among them, most noticeable are the EV-mediated enrichment of ncRNAs at the injury sites contributing the regulation of matrix remodeling, epithelial mesenchymal transitions, and attraction of fibroblasts. Additionally, we emphasize EV-mediated transmission of anti-inflammatory RNAs from stem cells to injury site that potentially orchestrate the resolution of the inflammatory responses and immune alleviation to better facilitate healing processes. Collectively, this knowledge indicates a high value and potential of EV-mediated RNA-based therapeutic approaches in regenerative medicine.

  12. Muscle Stem Cell Fate Is Controlled by the Cell-Polarity Protein Scrib

    Directory of Open Access Journals (Sweden)

    Yusuke Ono

    2015-02-01

    Full Text Available Satellite cells are resident skeletal muscle stem cells that supply myonuclei for homeostasis, hypertrophy, and repair in adult muscle. Scrib is one of the major cell-polarity proteins, acting as a potent tumor suppressor in epithelial cells. Here, we show that Scrib also controls satellite-cell-fate decisions in adult mice. Scrib is undetectable in quiescent cells but becomes expressed during activation. Scrib is asymmetrically distributed in dividing daughter cells, with robust accumulation in cells committed to myogenic differentiation. Low Scrib expression is associated with the proliferative state and preventing self-renewal, whereas high Scrib levels reduce satellite cell proliferation. Satellite-cell-specific knockout of Scrib in mice causes a drastic and insurmountable defect in muscle regeneration. Thus, Scrib is a regulator of tissue stem cells, controlling population expansion and self-renewal with Scrib expression dynamics directing satellite cell fate.

  13. Engineering Stem Cells for Biomedical Applications

    Science.gov (United States)

    Yin, Perry T.; Han, Edward

    2018-01-01

    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. PMID:25772134

  14. Engineering Stem Cells for Biomedical Applications.

    Science.gov (United States)

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

    2016-01-07

    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. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Senescence from glioma stem cell differentiation promotes tumor growth

    International Nuclear Information System (INIS)

    Ouchi, Rie; Okabe, Sachiko; Migita, Toshiro; Nakano, Ichiro; Seimiya, Hiroyuki

    2016-01-01

    Glioblastoma (GBM) is a lethal brain tumor composed of heterogeneous cellular populations including glioma stem cells (GSCs) and differentiated non-stem glioma cells (NSGCs). While GSCs are involved in tumor initiation and propagation, NSGCs' role remains elusive. Here, we demonstrate that NSGCs undergo senescence and secrete pro-angiogenic proteins, boosting the GSC-derived tumor formation in vivo. We used a GSC model that maintains stemness in neurospheres, but loses the stemness and differentiates into NSGCs upon serum stimulation. These NSGCs downregulated telomerase, shortened telomeres, and eventually became senescent. The senescent NSGCs released pro-angiogenic proteins, including vascular endothelial growth factors and senescence-associated interleukins, such as IL-6 and IL-8. Conditioned medium from senescent NSGCs promoted proliferation of brain microvascular endothelial cells, and mixed implantation of GSCs and senescent NSGCs into mice enhanced the tumorigenic potential of GSCs. The senescent NSGCs seem to be clinically relevant, because both clinical samples and xenografts of GBM contained tumor cells that expressed the senescence markers. Our data suggest that senescent NSGCs promote malignant progression of GBM in part via paracrine effects of the secreted proteins. - Highlights: • Non-stem glioma cells (NSGCs) lose telomerase and eventually become senescent. • Senescent NSGCs secrete pro-angiogenic proteins, such as VEGFs, IL-6, and IL-8. • Senescent NSGCs enhance the growth of brain microvascular endothelial cells. • Senescent NSGCs enhance the tumorigenic potential of glioma stem cells in vivo.

  16. Senescence from glioma stem cell differentiation promotes tumor growth

    Energy Technology Data Exchange (ETDEWEB)

    Ouchi, Rie [Division of Molecular Biotherapy, Cancer Chemotherapy Center, Japanese Foundation for Cancer Research, 3-8-31 Ariake, Koto-ku, Tokyo 135-8550 (Japan); Laboratory of Molecular Target Therapy of Cancer, Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, The University of Tokyo, 3-8-31 Ariake, Koto-ku, Tokyo 135-8550 (Japan); Okabe, Sachiko; Migita, Toshiro [Division of Molecular Biotherapy, Cancer Chemotherapy Center, Japanese Foundation for Cancer Research, 3-8-31 Ariake, Koto-ku, Tokyo 135-8550 (Japan); Nakano, Ichiro [Department of Neurosurgery, Comprehensive Cancer Center, University of Alabama at Birmingham, 1824 6th Avenue South, Birmingham, AL 35233 (United States); Seimiya, Hiroyuki, E-mail: hseimiya@jfcr.or.jp [Division of Molecular Biotherapy, Cancer Chemotherapy Center, Japanese Foundation for Cancer Research, 3-8-31 Ariake, Koto-ku, Tokyo 135-8550 (Japan); Laboratory of Molecular Target Therapy of Cancer, Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, The University of Tokyo, 3-8-31 Ariake, Koto-ku, Tokyo 135-8550 (Japan)

    2016-02-05

    Glioblastoma (GBM) is a lethal brain tumor composed of heterogeneous cellular populations including glioma stem cells (GSCs) and differentiated non-stem glioma cells (NSGCs). While GSCs are involved in tumor initiation and propagation, NSGCs' role remains elusive. Here, we demonstrate that NSGCs undergo senescence and secrete pro-angiogenic proteins, boosting the GSC-derived tumor formation in vivo. We used a GSC model that maintains stemness in neurospheres, but loses the stemness and differentiates into NSGCs upon serum stimulation. These NSGCs downregulated telomerase, shortened telomeres, and eventually became senescent. The senescent NSGCs released pro-angiogenic proteins, including vascular endothelial growth factors and senescence-associated interleukins, such as IL-6 and IL-8. Conditioned medium from senescent NSGCs promoted proliferation of brain microvascular endothelial cells, and mixed implantation of GSCs and senescent NSGCs into mice enhanced the tumorigenic potential of GSCs. The senescent NSGCs seem to be clinically relevant, because both clinical samples and xenografts of GBM contained tumor cells that expressed the senescence markers. Our data suggest that senescent NSGCs promote malignant progression of GBM in part via paracrine effects of the secreted proteins. - Highlights: • Non-stem glioma cells (NSGCs) lose telomerase and eventually become senescent. • Senescent NSGCs secrete pro-angiogenic proteins, such as VEGFs, IL-6, and IL-8. • Senescent NSGCs enhance the growth of brain microvascular endothelial cells. • Senescent NSGCs enhance the tumorigenic potential of glioma stem cells in vivo.

  17. Functionalized scaffolds to control dental pulp stem cell fate

    Science.gov (United States)

    Piva, Evandro; Silva, Adriana F.; Nör, Jacques E.

    2014-01-01

    Emerging understanding about interactions between stem cells, scaffolds and morphogenic factors has accelerated translational research in the field of dental pulp tissue engineering. Dental pulp stem cells constitute a sub-population of cells endowed with self-renewal and multipotency. Dental pulp stem cells seeded in biodegradable scaffolds and exposed to dentin-derived morphogenic signals give rise to a pulp-like tissue capable of generating new dentin. Notably, dentin-derived proteins are sufficient to induce dental pulp stem cell differentiation into odontoblasts. Ongoing work is focused on developing ways of mobilizing dentin-derived proteins and disinfecting the root canal of necrotic teeth without compromising the morphogenic potential of these signaling molecules. On the other hand, dentin by itself does not appear to be capable of inducing endothelial differentiation of dental pulp stem cells, despite the well known presence of angiogenic factors in dentin. This is particularly relevant in the context of dental pulp tissue engineering in full root canals, where access to blood supply is limited to the apical foramina. To address this challenge, scientists are looking at ways to use the scaffold as a controlled release device for angiogenic factors. The aim of this manuscript is to present and discuss current strategies to functionalize injectable scaffolds and customize them for dental pulp tissue engineering. The long-term goal of this work is to develop stem cell-based therapies that enable the engineering of functional dental pulps capable of generating new tubular dentin in humans. PMID:24698691

  18. Current Status on Stem Cells and Cancers of the Gastric Epithelium

    Directory of Open Access Journals (Sweden)

    Werner Hoffmann

    2015-08-01

    Full Text Available Gastric cancer is still a leading cause of cancer-related mortality worldwide in spite of declining incidence. Gastric cancers are, essentially, adenocarcinomas and one of the strongest risk factors is still infection with Helicobacter pylori. Within the last years, it became clear that gastric self-renewal and carcinogenesis are intimately linked, particularly during chronic inflammatory conditions. Generally, gastric cancer is now regarded as a disease resulting from dysregulated differentiation of stem and progenitor cells, mainly due to an inflammatory environment. However, the situation in the stomach is rather complex, consisting of two types of gastric units which show bidirectional self-renewal from an unexpectedly large variety of progenitor/stem cell populations. As in many other tumors, cancer stem cells have also been characterized for gastric cancer. This review focuses on the various gastric epithelial stem cells, how they contribute to self-renewal and which routes are known to gastric adenocarcinomas, including their stem cells.

  19. A novel method to generate and culture human mast cells: Peripheral CD34+ stem cell-derived mast cells (PSCMCs).

    Science.gov (United States)

    Schmetzer, Oliver; Valentin, Patricia; Smorodchenko, Anna; Domenis, Rossana; Gri, Giorgia; Siebenhaar, Frank; Metz, Martin; Maurer, Marcus

    2014-11-01

    The identification and characterization of human mast cell (MC) functions are hindered by the shortage of MC populations suitable for investigation. Here, we present a novel technique for generating large numbers of well differentiated and functional human MCs from peripheral stem cells (=peripheral stem cell-derived MCs, PSCMCs). Innovative and key features of this technique include 1) the use of stem cell concentrates, which are routinely discarded by blood banks, as the source of CD34+ stem cells, 2) cell culture in serum-free medium and 3) the addition of LDL as well as selected cytokines. In contrast to established and published protocols that use CD34+ or CD133+ progenitor cells from full blood, we used a pre-enriched cell population obtained from stem cell concentrates, which yielded up to 10(8) differentiated human MCs per batch after only three weeks of culture starting with 10(6) total CD34+ cells. The total purity on MCs (CD117+, FcεR1+) generated by this method varied between 55 and 90%, of which 4-20% were mature MCs that contain tryptase and chymase and show expression of FcεRI and CD117 in immunohistochemistry. PSCMCs showed robust histamine release in response to stimulation with anti-FcεR1 or IgE/anti-IgE, and increased proliferation and differentiation in response to IL-1β or IFN-γ. Taken together, this new protocol of the generation of large numbers of human MCs provides for an innovative and suitable option to investigate the biology of human MCs. Copyright © 2014 Elsevier B.V. All rights reserved.

  20. International Society for Stem Cell Research

    Science.gov (United States)

    ... renowned stem cell and regenerative medicine community. More stem cell research Take a closer look Recent Blogs View ... story independent nonprofit organization & the voice of the stem cell research community The International Society for Stem Cell ...