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Sample records for adult melanocyte stem

  1. The biology of melanocyte and melanocyte stem cell.

    PubMed

    Li, Ang

    2014-04-01

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

  2. NFIB is a governor of epithelial-melanocyte stem cell behaviour in a shared niche.

    PubMed

    Chang, Chiung-Ying; Pasolli, H Amalia; Giannopoulou, Eugenia G; Guasch, Géraldine; Gronostajski, Richard M; Elemento, Olivier; Fuchs, Elaine

    2013-03-07

    Adult stem cells reside in specialized niches where they receive environmental cues to maintain tissue homeostasis. In mammals, the stem cell niche within hair follicles is home to epithelial hair follicle stem cells and melanocyte stem cells, which sustain cyclical bouts of hair regeneration and pigmentation. To generate pigmented hairs, synchrony is achieved such that upon initiation of a new hair cycle, stem cells of each type activate lineage commitment. Dissecting the inter-stem-cell crosstalk governing this intricate coordination has been difficult, because mutations affecting one lineage often affect the other. Here we identify transcription factor NFIB as an unanticipated coordinator of stem cell behaviour. Hair follicle stem-cell-specific conditional targeting of Nfib in mice uncouples stem cell synchrony. Remarkably, this happens not by perturbing hair cycle and follicle architecture, but rather by promoting melanocyte stem cell proliferation and differentiation. The early production of melanin is restricted to melanocyte stem cells at the niche base. Melanocyte stem cells more distant from the dermal papilla are unscathed, thereby preventing hair greying typical of melanocyte stem cell differentiation mutants. Furthermore, we pinpoint KIT-ligand as a dermal papilla signal promoting melanocyte stem cell differentiation. Additionally, through chromatin-immunoprecipitation with high-throughput-sequencing and transcriptional profiling, we identify endothelin 2 (Edn2) as an NFIB target aberrantly activated in NFIB-deficient hair follicle stem cells. Ectopically induced Edn2 recapitulates NFIB-deficient phenotypes in wild-type mice. Conversely, endothelin receptor antagonists and/or KIT blocking antibodies prevent precocious melanocyte stem cell differentiation in the NFIB-deficient niche. Our findings reveal how melanocyte and hair follicle stem cell behaviours maintain reliance upon cooperative factors within the niche, and how this can be uncoupled in

  3. NFIB is a governor of epithelial–melanocyte stem cell behaviour in a shared niche

    PubMed Central

    Chang, Chiung-Ying; Pasolli, H. Amalia; Giannopoulou, Eugenia G.; Guasch, Géraldine; Gronostajski, Richard M.; Elemento, Olivier; Fuchs, Elaine

    2013-01-01

    Adult stem cells reside in specialized niches where they receive environmental cues to maintain tissue homeostasis. In mammals, the stem cell niche within hair follicles is home to epithelial hair follicle stem cells and melanocyte stem cells, which sustain cyclical bouts of hair regeneration and pigmentation1–4. To generate pigmented hairs, synchrony is achieved such that upon initiation of a new hair cycle, stem cells of each type activate lineage commitment2,5. Dissecting the inter-stem-cell crosstalk governing this intricate coordination has been difficult, because mutations affecting one lineage often affect the other. Here we identify transcription factor NFIB as an unanticipated coordinator of stem cell behaviour. Hair follicle stem-cell-specific conditional targeting of Nfib in mice uncouples stem cell synchrony. Remarkably, this happens not by perturbing hair cycle and follicle architecture, but rather by promoting melanocyte stem cell proliferation and differentiation. The early production of melanin is restricted to melanocyte stem cells at the niche base. Melanocyte stem cells more distant from the dermal papilla are unscathed, thereby preventing hair greying typical of melanocyte stem cell differentiation mutants. Furthermore, we pinpoint KIT-ligand as a dermal papilla signal promoting melanocyte stem cell differentiation. Additionally, through chromatin-immunoprecipitation with high-throughput-sequencing and transcriptional profiling, we identify endothelin 2 (Edn2) as an NFIB target aberrantly activated in NFIB-deficient hair follicle stem cells. Ectopically induced Edn2 recapitulates NFIB-deficient phenotypes in wild-type mice. Conversely, endothelin receptor antagonists and/or KIT blocking antibodies prevent precocious melanocyte stem cell differentiation in the NFIB-deficient niche. Our findings reveal how melanocyte and hair follicle stem cell behaviours maintain reliance upon cooperative factors within the niche, and how this can be uncoupled

  4. Immunohistochemical study of melanocyte-melanocyte stem cell lineage in vitiligo; a clue to interfollicular melanocyte stem cell reservoir.

    PubMed

    Seleit, Iman; Bakry, Ola Ahmed; Abdou, Asmaa Gaber; Dawoud, Noha Mohammed

    2014-05-01

    There has been a long lasting controversy over whether melanocytes (MCs) in vitiligo are actually lost or still present but functionally inactive. We aimed to evaluate the MC cell lineage in follicular and interfollicular vitiliginous epidermis through immunohistochemical localization of Human Melanoma Black-45 (HMB-45) and Tyrosinase Related Protein 2 (TRP2) and to correlate it with clinicopathologic parameters. Using immunohistochemical techniques, skin biopsies from 50 vitiligo patients and 20 age- and gender-matched healthy subjects were examined. Differentiated active MCs were detected in 44% of interfollicular epidermis (IFE) and 46.7% of follicular epidermis (FE) in lesional skin. Melanocyte precursors/stem cells were detected in 54% of IFE and 63.3% of FE in lesional skin. Melanocyte precursors/stem cells of IFE were significantly associated with residual melanin pigment (p = 0.007) and with absence of angiogenesis (p = 0.05). HMB-45 percentage of expression in IFE was positively correlated with MC precursors/stem cells percentage in FE (r = +0.65, p < 0.001) and IFE (r = +0.33, p = 0.01). Melanocyte precursors/stem cells positivity (p < 0.001) was progressively decreasing with advanced histopathologic grading. There was no significant association between interfollicular or follicular expression of HMB-45, TRP2 or MC precursors/stem cells and the clinical type of vitiligo or its duration. In conclusion, functioning MCs may exist in vitiligo. The presence of MC precursors/stem cells in IFE may provide an additional reservoir needed for repigmentation.

  5. EdnrB governs regenerative response of melanocyte stem cells by crosstalk with Wnt signaling

    PubMed Central

    Takeo, Makoto; Lee, Wendy; Rabbani, Piul; Sun, Qi; Hu, Hai; Lim, Chae Ho; Manga, Prashiela; Ito, Mayumi

    2017-01-01

    Delineating the crosstalk between distinct signaling pathways is key to understanding the diverse and dynamic responses of adult stem cells during tissue regeneration. Here we demonstrate that the Edn/EdnrB signaling pathway can interact with other signaling pathways to elicit distinct stem cell functions during tissue regeneration. EdnrB signaling promotes proliferation and differentiation of melanocyte stem cells (McSCs), dramatically enhancing the regeneration of hair and epidermal melanocytes. This effect is dependent upon active Wnt signaling that is initiated by Wnt ligand secretion from the hair follicle epithelial niche. Further, this Wnt-dependent EdnrB signaling can rescue the defects in melanocyte regeneration caused by Mc1R loss. This suggests that targeting Edn/EdnrB signaling in McSCs can be a therapeutic approach to promote photoprotective-melanocyte regeneration, which may be useful for those with increased risk of skin cancers due to Mc1R variants. PMID:27134165

  6. Understanding Melanocyte Stem Cells for Disease Modeling and Regenerative Medicine Applications.

    PubMed

    Mull, Amber N; Zolekar, Ashwini; Wang, Yu-Chieh

    2015-12-21

    Melanocytes in the skin play an indispensable role in the pigmentation of skin and its appendages. It is well known that the embryonic origin of melanocytes is neural crest cells. In adult skin, functional melanocytes are continuously repopulated by the differentiation of melanocyte stem cells (McSCs) residing in the epidermis of the skin. Many preceding studies have led to significant discoveries regarding the cellular and molecular characteristics of this unique stem cell population. The alteration of McSCs has been also implicated in several skin abnormalities and disease conditions. To date, our knowledge of McSCs largely comes from studying the stem cell niche of mouse hair follicles. Suggested by several anatomical differences between mouse and human skin, there could be distinct features associated with mouse and human McSCs as well as their niches in the skin. Recent advances in human pluripotent stem cell (hPSC) research have provided us with useful tools to potentially acquire a substantial amount of human McSCs and functional melanocytes for research and regenerative medicine applications. This review highlights recent studies and progress involved in understanding the development of cutaneous melanocytes and the regulation of McSCs.

  7. Differentiating the stem cell pool of human hair follicle outer root sheath into functional melanocytes.

    PubMed

    Schneider, Marie; Dieckmann, Christina; Rabe, Katrin; Simon, Jan-Christoph; Savkovic, Vuk

    2014-01-01

    Bench-to-Bedside concepts for regenerative therapy place significant weight on noninvasive approaches, with harvesting of the starting material as a header. This is particularly important in autologous treatments, which use one's bodily constituents for therapy. Precisely the stretch between obtaining therapeutic elements invasively and noninvasively places non-intrusive "sampling" rather than "biopsy" in the center of the road map of developing an autologous regenerative therapy. We focus on such a noninvasively available source of adult stem cells that we carry with us throughout our life, available at our fingertips-or shall we say hair roots, by a simple plucking of hair: the human hair follicle. This chapter describes an explant procedure for cultivating melanocytes differentiated from the stem cell pool of the hair follicle Outer Root Sheath (ORS). In vivo, the most abundant derivatives of the heterogeneous ORS stem cell pool are epidermal cells-melanocytes and keratinocytes which complete their differentiation-either spontaneously or upon picking up regenerative cues from damaged skin-and migrate from the ORS towards the adjacent regenerating area of the epidermis. We have taken advantage of the ORS developmental potential by optimizing explant primary culture, expansion and melanogenic differentiation of resident ORS stem cells towards end-stage melanocytes in order to obtain functional melanocytes noninvasively for the purposes of transplantation and use them for the treatment of depigmentation disorders. Our protocol specifies sampling of hair with their ORS, follicle medium-air interface primary culture, stimulation of cell outgrowth, adherent culture and differentiation of ORS stem cells and precursors towards fully functional melanocytes. Along with cultivation, we describe selection techniques for establishing and maintaining a pure melanocyte population and methods suitable for determining melanocyte identity.

  8. In vitro dedifferentiation of melanocytes from adult epidermis.

    PubMed

    Kormos, Bernadett; Belso, Nóra; Bebes, Attila; Szabad, Gábor; Bacsa, Sarolta; Széll, Márta; Kemény, Lajos; Bata-Csörgo, Zsuzsanna

    2011-02-23

    In previous work we described a novel culture technique using a cholera toxin and PMA-free medium (Mel-mix) for obtaining pure melanocyte cultures from human adult epidermis. In Mel-mix medium the cultured melanocytes are bipolar, unpigmented and highly proliferative. Further characterization of the cultured melanocytes revealed the disappearance of c-Kit and TRP-1 and induction of nestin expression, indicating that melanocytes dedifferentiated in this in vitro culture. Cholera toxin and PMA were able to induce c-Kit and TRP-1 protein expressions in the cells, reversing dedifferentiation. TRP-1 mRNA expression was induced in dedifferentiated melanocytes by UV-B irradiated keratinocyte supernatants, however direct UV-B irradiation of the cells resulted in further decrease of TRP-1 mRNA expression. These dedifferentiated, easily accessible cultured melanocytes provide a good model for studying melanocyte differentiation and possibly transdifferentiation. Because melanocytes in Mel-mix medium can be cultured with human serum as the only supplement, this culture system is also suitable for autologous cell transplantation.

  9. Adipose-Derived Stem Cells Improve Efficacy of Melanocyte Transplantation in Animal Skin

    PubMed Central

    Lim, Won-Suk; Kim, Chang-Hyun; Kim, Ji-Young; Do, Byung-Rok; Kim, Eo Jin; Lee, Ai-Young

    2014-01-01

    Vitiligo is a pigmentary disorder induced by a loss of melanocytes. In addition to replacement of pure melanocytes, cocultures of melanocytes with keratinocytes have been used to improve the repigmentation outcome in vitiligo treatment. We previously identified by in vitro studies, that adipose-derived stem cells (ADSCs) could be a potential substitute for keratinocytes in cocultures with melanocytes. In this study, the efficacy of pigmentation including durability of grafted melanocytes and short-term safety was examined in the nude mouse and Sprague-Dawley rat after grafting of primary cultured human melanocytes, with or without different ratios of primary cultured human ADSCs. Simultaneous grafting of melanocytes and ADSCs, which were separately cultured and mixed on grafting at the ratios of 1:1, 1:2, or 1:3, showed better efficacy than that of pure melanocytes. Grafting of melanocytes cocultured with ADSCs resulted in a similar outcome as the grafting of cell mixtures. Skin pigmentation by melanocytes : ADSCs at the ratios of 1:1 and 1:2 was better than at 1:3. No significant difference was observed between the 1-week and 2-week durations in coculturing. Time-course microscopic examination showed that the grafted melanocytes remained a little longer than 6-week post-grafting. No inflammatory cell infiltration was observed in the grafted skin and no melanocytes were detectable in other organs. Collectively, grafting of melanocytes and ADSCs was equally safe and more effective than grafting of melanocytes alone. Despite the absence of significant differences in efficacy between the group of 1:1 and that of 1:2 ratio, 1:2 ratio for 1-week coculturing may be better for clinical use from the cost-benefit viewpoint. PMID:25143812

  10. A new transgenic mouse line for tetracycline inducible transgene expression in mature melanocytes and the melanocyte stem cells using the Dopachrome tautomerase promoter.

    PubMed

    Woods, Susan L; Bishop, J Michael

    2011-04-01

    We have generated a novel transgenic mouse to direct inducible and reversible transgene expression in the melanocytic compartment. The Dopachrome tautomerase (Dct) control sequences we used are active early in the development of melanocytes and so this system was designed to enable the manipulation of transgene expression during development in utero and in the melanocyte stem cells as well as mature melanocytes. We observed inducible lacZ and GFP reporter transgene activity specifically in melanocytes and melanocyte stem cells in mouse skin. This mouse model will be a useful tool for the pigment cell community to investigate the contribution of candidate genes to normal melanocyte and/or melanoma development in vivo. Deregulated expression of the proto-oncogene MYC has been observed in melanoma, however whether MYC is involved in tumorigenesis in pigment cells has yet to be directly investigated in vivo. We have used our system to over-express MYC in the melanocytic compartment and show for the first time that increased MYC expression can indeed promote melanocytic tumor formation.

  11. Functional melanocytes are readily reprogrammable from multilineage-differentiating stress-enduring (muse) cells, distinct stem cells in human fibroblasts.

    PubMed

    Tsuchiyama, Kenichiro; Wakao, Shohei; Kuroda, Yasumasa; Ogura, Fumitaka; Nojima, Makoto; Sawaya, Natsue; Yamasaki, Kenshi; Aiba, Setsuya; Dezawa, Mari

    2013-10-01

    The induction of melanocytes from easily accessible stem cells has attracted attention for the treatment of melanocyte dysfunctions. We found that multilineage-differentiating stress-enduring (Muse) cells, a distinct stem cell type among human dermal fibroblasts, can be readily reprogrammed into functional melanocytes, whereas the remainder of the fibroblasts do not contribute to melanocyte differentiation. Muse cells can be isolated as cells positive for stage-specific embryonic antigen-3, a marker for undifferentiated human embryonic stem cells, and differentiate into cells representative of all three germ layers from a single cell, while also being nontumorigenic. The use of certain combinations of factors induces Muse cells to express melanocyte markers such as tyrosinase and microphthalmia-associated transcription factor and to show positivity for the 3,4-dihydroxy-L-phenylalanine reaction. When Muse cell-derived melanocytes were incorporated into three-dimensional (3D) cultured skin models, they localized themselves in the basal layer of the epidermis and produced melanin in the same manner as authentic melanocytes. They also maintained their melanin production even after the 3D cultured skin was transplanted to immunodeficient mice. This technique may be applicable to the efficient production of melanocytes from accessible human fibroblasts by using Muse cells, thereby contributing to autologous transplantation for melanocyte dysfunctions, such as vitiligo.

  12. Hesperetin induces melanin production in adult human epidermal melanocytes.

    PubMed

    Usach, Iris; Taléns-Visconti, Raquel; Magraner-Pardo, Lorena; Peris, José-Esteban

    2015-06-01

    One of the major sources of flavonoids for humans are citrus fruits, hesperidin being the predominant flavonoid. Hesperetin (HSP), the aglycon of hesperidin, has been reported to provide health benefits such as antioxidant, anti-inflammatory and anticarcinogenic effects. However, the effect of HSP on skin pigmentation is not clear. Some authors have found that HSP induces melanogenesis in murine B16-F10 melanoma cells, which, if extrapolated to in vivo conditions, might protect skin against photodamage. Since the effect of HSP on normal melanocytes could be different to that observed on melanoma cells, the described effect of HSP on murine melanoma cells has been compared to the effect obtained using normal human melanocytes. HSP concentrations of 25 and 50 µM induced melanin synthesis and tyrosinase activity in human melanocytes in a concentration-dependent manner. Compared to control melanocytes, 25 µM HSP increased melanin production and tyrosinase activity 1.4-fold (p < 0.01) and 1.1-fold (p < 0.01), respectively, and the corresponding increases in the case of 50 µM HSP were 1.9-fold (p < 0.001) and 1.3-fold (p < 0.001). Therefore, HSP could be considered a valuable photoprotective substance if its capacity to increase melanin production in human melanocyte cultures could be reproduced on human skin.

  13. Limbal melanocytes support limbal epithelial stem cells in 2D and 3D microenvironments.

    PubMed

    Dziasko, Marc A; Tuft, Stephen J; Daniels, Julie T

    2015-09-01

    Human limbal epithelial stem cells (LESCs) are essential for the maintenance of the corneal epithelium of the ocular surface. LESCs are located within limbal crypts between the palisades of Vogt in the limbus; the interface between the peripheral cornea and conjunctiva. The limbal crypts have been proposed as a LESC niche owing to their support of epithelial cells, which can form holoclone colonies in vitro. Closely associated with the limbal crypts is a concentrated population of melanocytes. The anatomical location and close proximity to putative LESC suggests that melanocytes might play a role in maintenance of these stem cells in the niche. The aim of this study was to assess the ability of human limbal melanocytes (hLM) to support the expansion of human limbal epithelial cells (LECs) in vitro as an indicator of functional cell-cell interaction. After observing that hLM co-localize with clusters of compact epithelial cells in the native limbal crypts, hLM were isolated from crypt-rich cadaveric limbal biopsies and used as feeders for the culture of LECs. Interestingly, LECs grown on mitotically active hLM were able to generate large epithelial colonies that contained small and compact cells with morphological stem cell characteristics. Immunocytochemistry revealed that LECs expanded on hLM were positive for the expression of the putative stem cell markers CK15, Bmi-1 and p63α and negative for the marker of terminal cell differentiation CK3. LECs and hLM were finally co-cultured on RAFT (real architecture for 3D tissue) collagen tissue equivalents. In 3D co-cultures, hLM promoted multi-layering of the epithelial sheet in which basal cells were maintained in an undifferentiated state. Taken together, these observations suggest melanocytes could play an important role in the maintenance of LESCs in the native human limbal stem cell niche.

  14. Risk of melanocytic nevi and nonmelanoma skin cancer in children after allogeneic hematopoietic stem cell transplantation.

    PubMed

    Song, J S; London, W B; Hawryluk, E B; Guo, D; Sridharan, M; Fisher, D E; Lehmann, L E; Duncan, C N; Huang, J T

    2017-04-03

    There is a known increased risk of skin cancer in the adult population after hematopoietic stem cell transplantation (HSCT). However, late dermatologic effects that children may experience after HSCT have not been well described. The primary objective of this study was to characterize nevi and skin cancers affecting children after allogeneic HSCT. A cross-sectional cohort study of 85 pediatric HSCT recipients and 85 controls matched for age, sex and skin phototype was performed at a single institution. All participants underwent a full skin examination. Median age at study visit was 13.8 years in HSCT patients with median time post-HSCT of 3.6 years. HSCT patients had significantly more nevi than control patients (median (range): 44 (0-150) vs 11 (0-94), P<0.0001). HSCT patients also had significantly more nevi >5 mm in diameter and atypical nevi than controls. Factors associated with increased nevus count included malignant indication for HSCT, pretransplant chemotherapy, TBI exposure and myeloablative conditioning. A total of 16.5% of HSCT patients developed cancerous, precancerous lesions and/or lentigines. Our study suggests that pediatric HSCT recipients have an increased risk of benign and atypical melanocytic proliferations and nonmelanoma skin cancer that can manifest even during childhood.Bone Marrow Transplantation advance online publication, 3 April 2017; doi:10.1038/bmt.2017.57.

  15. Management considerations for giant congenital melanocytic nevi in adults.

    PubMed

    Green, Margaret C; Mitchum, Marsha D; Marquart, Jason D; Bingham, Jonathan L

    2014-04-01

    Giant congenital melanocytic nevi (GCMN) are a rare type of melanocytic nevus that covers a large body surface, often with satellite nevi scattered on the rest of the skin. There are several complications associated with GCMN, including malignant melanoma and neurocutaneous melanosis. The management of GCMN is very complex because of the cosmetic appearance and the associated psychological distress, the risk of severe complications, and the need for long-term follow-up. We report a case of a 43-year-old active-duty female with a GCMN reporting new and symptomatic satellite lesions with atypical features on dermoscopy.

  16. Pigmentation PAX-ways: The role of Pax3 in melanogenesis, melanocyte stem cell maintenance, and disease

    PubMed Central

    Kubic, Jennifer D.; Young, Kacey P.; Plummer, Rebecca S.; Ludvik, Anton E.; Lang, Deborah

    2010-01-01

    Transcription factors initiate a program of gene expression and are catalysts in downstream molecular cascades that modulate a variety of cellular processes. Pax3 is a transcription factor that is important in the melanocyte and influences melanocytic proliferation, resistance to apoptosis, migration, lineage specificity and differentiation. In this review, we focus on Pax3 and the molecular pathways that Pax3 is a part of during melanogenesis and in the melanocyte stem cell. These roles of Pax3 are emphasized during the development of diseases and syndromes resulting from either too much or too little Pax3 function. Due to its key task in melanocyte stem cells and tumors, the Pax3 pathway may provide an ideal target for either stem cell or cancer therapies. PMID:18983540

  17. Treatment of a giant congenital melanocytic nevus in the adult: review of the current management of giant congenital melanocytic nevus.

    PubMed

    Su, Jeannie J; Chang, Daniel K; Mailey, Brian; Gosman, Amanda

    2015-05-01

    Giant congenital melanocytic nevi (GCMNs) create cosmetic disfigurements and pose risk for malignant transformation. Adult GCMN cases are uncommon because most families opt for surgical treatment during childhood. We review the current literature on GCMN and present an interesting case of an adult with a GCMN encompassing the entire back with painful nodules exhibiting gross involvement of his back musculature, without pathologic evidence of malignancy. Surgical management was deferred in childhood because of parental desires to allow the patient to make his own decision, and treatment in adulthood was pursued on the basis of the significant impairment of the patient's quality of life and self-esteem due to the massive size and deforming nature of the nevus. The treatment strategy used for this young adult male patient involved a massive en bloc excision of the GCMN with partial resection of the latissimus dorsi, followed by a 5-week staged reconstructive process using dermal regenerative matrices and split-thickness skin grafting. Because of the shift in GCMN management from early surgical management to more conservative management, we may see an increase in adult cases of GCMN. Thus, it is critical to better understand the controversy surrounding early versus delayed management of GCMN.

  18. Metastatic melanoma in association with a giant congenital melanocytic nevus in an adult: controversial CGH findings.

    PubMed

    Machan, Salma; Molina-Ruiz, Ana M; Fernández-Aceñero, Maria J; Encabo, Beatriz; LeBoit, Philip; Bastian, Boris C; Requena, Luis

    2015-06-01

    Giant congenital melanocytic nevi (GCMNs) represent a distress to patients for 2 reasons: one is disfigurement, and the other is the increased risk of developing secondary melanocytic tumors, such as benign proliferative nodules (BPNs) and malignant melanoma (MM). BPN present as a rapid growth nodule arising within a congenital melanocytic nevus (CMN) that often ulcerates, occurs in children younger than 2 years of age. BPNs arising within a CMN are exceedingly rare after childhood, and very few cases have been described in adults. Despite the worrisome clinical and histologic findings of BPN, most laboratory investigations seem to support their benignity. The distinction between MM and BPN is extremely important, but the histopathology of BPN of GCMN can be a challenge to differentiate from MM. In the recent years, molecular tests that investigate DNA copy number alterations such as fluorescence in situ hybridization and comparative genomic hybridization have shown promise to help guide the diagnosis of ambiguous melanocytic proliferations arising within CMNs. We report the case of a 22-year-old woman with a nodule arising in a GCMN and with an axillary mass suggesting a nodal metastasis of melanoma, and discuss the unusual clinical, histopathologic, and molecular findings that make this case particularly interesting.

  19. Differential PAX3 functions in normal skin melanocytes and melanoma cells

    SciTech Connect

    Medic, Sandra; Rizos, Helen; Ziman, Mel

    2011-08-12

    Highlights: {yields} PAX3 retains embryonic roles in adult melanocytes and melanoma cells. {yields} Promotes 'stem' cell-like phenotype via NES and SOX9 in both cells types. {yields} Regulates melanoma and melanocyte migration through MCAM and CSPG4. {yields} PAX3 regulates melanoma but not melanocyte proliferation via TPD52. {yields} Regulates melanoma cell (but not melanocyte) survival via BCL2L1 and PTEN. -- Abstract: The PAX3 transcription factor is the key regulator of melanocyte development during embryogenesis and is also frequently found in melanoma cells. While PAX3 is known to regulate melanocyte differentiation, survival, proliferation and migration during development, it is not clear if its function is maintained in adult melanocytes and melanoma cells. To clarify this we have assessed which genes are targeted by PAX3 in these cells. We show here that similar to its roles in development, PAX3 regulates complex differentiation networks in both melanoma cells and melanocytes, in order to maintain cells as 'stem' cell-like (via NES and SOX9). We show also that mediators of migration (MCAM and CSPG4) are common to both cell types but more so in melanoma cells. By contrast, PAX3-mediated regulation of melanoma cell proliferation (through TPD52) and survival (via BCL2L1 and PTEN) differs from that in melanocytes. These results suggest that by controlling cell proliferation, survival and migration as well as maintaining a less differentiated 'stem' cell like phenotype, PAX3 may contribute to melanoma development and progression.

  20. Adult stem cell therapy: dream or reality?

    PubMed

    Moraleda, Jose M; Blanquer, Miguel; Bleda, Patricia; Iniesta, Paqui; Ruiz, Francisco; Bonilla, Sonia; Cabanes, Carmen; Tabares, Lucía; Martinez, Salvador

    2006-12-01

    Adult stem cells may be an invaluable source of plastic cells for tissue regeneration. The bone marrow contains different subpopulations of adult stem cells easily accessible for transplantation. However the therapeutic value of adult stem cell is a question of debate in the scientific community. We have investigated the potential benefits of adult hematopoietic stem cell transplantation in animal models of demyelinating and motor neuron diseases. Our results suggest that transplantation of HSC have direct and indirect neuroregenerative and neuroprotective effects.

  1. Intelligent bioengineering in vitiligo treatment: transdermal protein transduction of melanocyte-lineage-specific genes.

    PubMed

    Mou, Yi; Jiang, Xian; Du, Yu; Xue, Li

    2012-12-01

    Vitiligo is a common, incurable skin disease with a prevalence of about 1%. Although many vitiligo therapies are available in clinics, there is almost no one method that causes significant improvement in all vitiligo patients. Some have hypothesized that melanocyte dysfunction or deficiency underlies the loss of skin pigmentation observed in vitiligo. The autoimmune-mediated apoptosis of melanocytes might be an important part of the etiology of vitiligo, which prevents the formation of melanocytes in the skin. Here we propose a novel hypothesis for vitiligo treatment using in situ melanocyte regeneration induced by melanocyte-lineage-specific genes (MLSGs). This may serve as an intelligent bioengineering prototype. The hypothesis is based on the fact that MLSGs regulate melanocyte differentiation through epigenetic reprogramming, which includes microphthalmia-associated transcription factor (MITF), paired box 3 (PAX3), and Notch signaling. MITF directs the terminal differentiation of melanocytes, and PAX3 helps to establish the properties of the melanocyte stem cells. Notch signaling promotes adult stem cell proliferation and self-renewal. This process could be mimicked by Notch intracellular domain (NICD). MLSGs could also stimulate anti-apoptotic gene expression. Recent improvements in relevant biotechniques allow the transdermal delivery of MLSG proteins into the patient, where they enter cells through protein transduction. This process may promote melanocyte regeneration in situ with little impact on the hair follicular cycle or on carcinogenesis. This simple and efficient treatment may have significant impact on the treatment of vitiligo patients.

  2. In vitro modeling of hyperpigmentation associated to neurofibromatosis type 1 using melanocytes derived from human embryonic stem cells

    PubMed Central

    Allouche, Jennifer; Bellon, Nathalia; Saidani, Manoubia; Stanchina-Chatrousse, Laure; Masson, Yolande; Patwardhan, Anand; Gilles-Marsens, Floriane; Delevoye, Cédric; Domingues, Sophie; Nissan, Xavier; Martinat, Cécile; Lemaitre, Gilles; Peschanski, Marc; Baldeschi, Christine

    2015-01-01

    “Café-au-lait” macules (CALMs) and overall skin hyperpigmentation are early hallmarks of neurofibromatosis type 1 (NF1). One of the most frequent monogenic diseases, NF1 has subsequently been characterized with numerous benign Schwann cell-derived tumors. It is well established that neurofibromin, the NF1 gene product, is an antioncogene that down-regulates the RAS oncogene. In contrast, the molecular mechanisms associated with alteration of skin pigmentation have remained elusive. We have reassessed this issue by differentiating human embryonic stem cells into melanocytes. In the present study, we demonstrate that NF1 melanocytes reproduce the hyperpigmentation phenotype in vitro, and further characterize the link between loss of heterozygosity and the typical CALMs that appear over the general hyperpigmentation. Molecular mechanisms associated with these pathological phenotypes correlate with an increased activity of cAMP-mediated PKA and ERK1/2 signaling pathways, leading to overexpression of the transcription factor MITF and of the melanogenic enzymes tyrosinase and dopachrome tautomerase, all major players in melanogenesis. Finally, the hyperpigmentation phenotype can be rescued using specific inhibitors of these signaling pathways. These results open avenues for deciphering the pathological mechanisms involved in pigmentation diseases, and provide a robust assay for the development of new strategies for treating these diseases. PMID:26150484

  3. In vitro modeling of hyperpigmentation associated to neurofibromatosis type 1 using melanocytes derived from human embryonic stem cells.

    PubMed

    Allouche, Jennifer; Bellon, Nathalia; Saidani, Manoubia; Stanchina-Chatrousse, Laure; Masson, Yolande; Patwardhan, Anand; Gilles-Marsens, Floriane; Delevoye, Cédric; Domingues, Sophie; Nissan, Xavier; Martinat, Cécile; Lemaitre, Gilles; Peschanski, Marc; Baldeschi, Christine

    2015-07-21

    "Café-au-lait" macules (CALMs) and overall skin hyperpigmentation are early hallmarks of neurofibromatosis type 1 (NF1). One of the most frequent monogenic diseases, NF1 has subsequently been characterized with numerous benign Schwann cell-derived tumors. It is well established that neurofibromin, the NF1 gene product, is an antioncogene that down-regulates the RAS oncogene. In contrast, the molecular mechanisms associated with alteration of skin pigmentation have remained elusive. We have reassessed this issue by differentiating human embryonic stem cells into melanocytes. In the present study, we demonstrate that NF1 melanocytes reproduce the hyperpigmentation phenotype in vitro, and further characterize the link between loss of heterozygosity and the typical CALMs that appear over the general hyperpigmentation. Molecular mechanisms associated with these pathological phenotypes correlate with an increased activity of cAMP-mediated PKA and ERK1/2 signaling pathways, leading to overexpression of the transcription factor MITF and of the melanogenic enzymes tyrosinase and dopachrome tautomerase, all major players in melanogenesis. Finally, the hyperpigmentation phenotype can be rescued using specific inhibitors of these signaling pathways. These results open avenues for deciphering the pathological mechanisms involved in pigmentation diseases, and provide a robust assay for the development of new strategies for treating these diseases.

  4. VITILIGO AND THE MELANOCYTE RESERVOIR

    PubMed Central

    Falabella, Rafael

    2009-01-01

    Repigmentation of vitiligo depends on available melanocytes from three possible sources: from the hair follicle unit which is the main provider of pigment cells, from the border of vitiligo lesions, and from unaffected melanocytes within depigmented areas; pigment cells at these locations originate a perifollicular, border spreading and a diffuse repigmentation pattern. In order for repigmentation to take place under stimulation with diverse therapies, melanocytes should be present in appropriate numbers. Melanocyte tissue stem cells located in the niche at the bulge region of the hair follicle are the most important sources for providing immature pigment cells that undergo terminal differentiation and originate repigmentation, but cytokines, UVR and other molecules acting in melanogenesis with adequate regulation mechanisms contribute to successful recovery in vitiligo. The presence of keratinocyte stem cells in the interfollicular epidermis raises the question on the possibility of melanocyte stem cells in a similar location and the development of future strategies for therapeutic purposes. PMID:20101329

  5. Generalized Potential of Adult Neural Stem Cells

    NASA Astrophysics Data System (ADS)

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

    2000-06-01

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

  6. Transforming growth factor beta1 regulates melanocyte proliferation and differentiation in mouse neural crest cells via stem cell factor/KIT signaling.

    PubMed

    Kawakami, Tamihiro; Soma, Yoshinao; Kawa, Yoko; Ito, Masaru; Yamasaki, Emiko; Watabe, Hidenori; Hosaka, Eri; Yajima, Kenji; Ohsumi, Kayoko; Mizoguchi, Masako

    2002-03-01

    Stem cell factor is essential to the migration and differentiation of melanocytes during embryogenesis based on the observation that mutations in either the stem cell factor gene, or its ligand, KIT, result in defects in coat pigmentation in mice. Stem cell factor is also required for the survival of melanocyte precursors while they are migrating towards the skin. Transforming growth factor beta1 has been implicated in the regulation of both cellular proliferation and differentiation. NCC-melb4, an immortal cloned cell line, was cloned from a mouse neural crest cell. NCC-melb4 cells provide a model to study the specific stage of differentiation and proliferation of melanocytes. They also express KIT as a melanoblast marker. Using the NCC-melb4 cell line, we investigated the effect of transforming growth factor beta1 on the differentiation and proliferation of immature melanocyte precursors. Immunohistochemically, NCC-melb4 cells showed transforming growth factor beta1 expression. The anti-transforming growth factor beta1 antibody inhibited the cell growth, and downregulated the KIT protein and mRNA expression. To investigate further the activation of autocrine transforming growth factor beta1, NCC-melb4 cells were incubated in nonexogenous transforming growth factor beta1 culture medium. KIT protein decreased with anti-transforming growth factor beta1 antibody concentration in a concentration-dependent manner. We concluded that in NCC-melb4 cells, transforming growth factor beta1 promotes melanocyte precursor proliferation in autocrine and/or paracrine regulation. We further investigated the influence of transforming growth factor beta1 in vitro using a neural crest cell primary culture system from wild-type mice. Anti-transforming growth factor beta1 antibody decreased the number of KIT positive neural crest cell. In addition, the anti-transforming growth factor beta1 antibody supplied within the wild-type neural crest explants abolished the growth of the neural

  7. Melanocytes: the new Black.

    PubMed

    Goding, Colin R

    2007-01-01

    Melanocytes, pigment-producing cells residing primarily in the hair follicle, epidermis and eye, are responsible for skin hair and eye pigmentation. Pigmentation is achieved by the highly regulated manufacture of the pigment melanin in specialised organelles, melanosomes that are transported along dendritic processes before being transferred to growing hair, or keratinocytes where melanin protects from UV-induced DNA damage. Because loss of melanocytes gives a clear pigmentation phenotype yet is non-lethal, over 130 genes implicated in the development or function of this cell type have been identified to date, and in humans the loss of melanocytes or their ability to produce pigment, or transport or transfer melanosomes is associated with several diseases such as vitiligo, albinism and Hermansky-Pudlak syndrome. Importantly, the effective combination of genetics, cell and molecular biology possible with this cell type is attracting an increasing number of researchers focussed on understanding how cells coordinate survival, proliferation, differentiation and stem cell maintenance.

  8. Basal cell carcinoma arising in a congenital melanocytic naevus in an adult.

    PubMed

    Cooper, Lillian; Srinivasan, Karthik; Nugent, Nora

    2017-02-13

    Congenital melanocytic naevi (CMN) are common skin lesions. They harbour a risk of malignant transformation, and various lesions have been described as developing within them. A basal cell cancer occurring within a CMN has never previously been described. A case is described of a woman aged 52 years presenting with a slow-growing, symptomatic 3 cm lesion in the centre of a 10×5 cm CMN on her right upper back. Diagnostic core biopsy revealed an ulcerated, infiltrative basal cell carcinoma which was then further excised. The scar has healed with no evidence of local recurrence at 1-year follow-up.

  9. Adult Stem Cells and Diseases of Aging

    PubMed Central

    Boyette, Lisa B.; Tuan, Rocky S.

    2014-01-01

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

  10. Dermal Mesenchymal Stem Cells (DMSCs) Inhibit Skin-Homing CD8+ T Cell Activity, a Determining Factor of Vitiligo Patients’ Autologous Melanocytes Transplantation Efficiency

    PubMed Central

    Wu, Ji-long; Lin, Fu-quan; Fu, Li-fang; Wang, Sui-quan; Guan, Cui-ping; Wang, Hong-lin; Xu, Aie

    2013-01-01

    We here investigated the efficiency of autologous melanocyte transplantation of 23 vitiligo patients by focusing on perilesional skin homing CD8+ T lymphocytes, and studied the potential effect of dermal mesenchymal stem cells (DMSCs) on CD8+ T cell activities in vitro. Out of 23 patients with the autologous melanocyte transplantation, 12 patients (52.17%) had an excellent re-pigmentation, 6 patients (26.09%) had a good re-pigmentation, 5 patients (21.74%) had a fair or poor re-pigmentation. CD8+ T cells infiltrating was observed in the perilesional vitiligo area of all patients. Importantly, the efficiency of the transplantation was closely associated with skin-homing CD8+ T cell activities. The patients with high number of perilesional CD8+ T cells or high level of cytokines/chemokines were associated with poor re-pigmentation efficiency. For in-vitro experiments, we successfully isolated and characterized human DMSCs and skin-homing CD8+ T cells. We established DMSCs and CD8+ T cell co-culture system, where DMSCs possessed significant inhibitory effects against skin homing CD8+ T lymphocytes. DMSCs inhibited CD8+ T cells proliferation, induced them apoptosis and regulated their cytokines/chemokines production. Our results suggest that vitiligo patients’ autologous melanocytes transplantation efficiency might be predicted by perilesional skin-homing CD8+ T cell activities, and DMSCs might be used as auxiliary agent to improve transplantation efficacy. PMID:23577097

  11. [Application prospect of adult stem cells in male infertility].

    PubMed

    Yang, Rui-Feng; Xiong, Cheng-Liang

    2013-05-01

    The study on stem cells is a hot field in biomedical science in recent years, and has furthered from laboratory to clinical application. Stem cells, according to their developmental stage and differential properties, can be divided into embryonic stem cells, induced PS cells and adult stem cells, among which, adult stem cells have already been applied to the clinical treatment of many systemic diseases. Currently, the study of spermatogonial stem cells and adult stem cells is in the front of the basic researches on the treatment of male infertility, but the time has not yet arrived for their clinical application. This paper outlines the application prospect of adult stem cells in male infertility.

  12. The melanocyte lineage in development and disease

    PubMed Central

    Mort, Richard L.; Jackson, Ian J.; Patton, E. Elizabeth

    2015-01-01

    Melanocyte development provides an excellent model for studying more complex developmental processes. Melanocytes have an apparently simple aetiology, differentiating from the neural crest and migrating through the developing embryo to specific locations within the skin and hair follicles, and to other sites in the body. The study of pigmentation mutations in the mouse provided the initial key to identifying the genes and proteins involved in melanocyte development. In addition, work on chicken has provided important embryological and molecular insights, whereas studies in zebrafish have allowed live imaging as well as genetic and transgenic approaches. This cross-species approach is powerful and, as we review here, has resulted in a detailed understanding of melanocyte development and differentiation, melanocyte stem cells and the role of the melanocyte lineage in diseases such as melanoma. PMID:25670789

  13. Comparison of high-intensity ultraviolet and NB-UVB on the maturation of melanocytes derived from hair follicle neural crest stem cells.

    PubMed

    Dong, Dake; Chen, Shujun; Zhang, Xiaoli; Jin, Cheng; Zheng, Yuan; Yang, Lijia

    2014-09-01

    Both high-intensity ultraviolet and narrowband ultraviolet B (NB-UVB) are important therapeutic options for vitiligo management, but high-intensity ultraviolet is more effective than NB-UVB. However, the underlying mechanisms have not been well investigated. Herein, we compare the effects of high-intensity ultraviolet and NB-UVB on the pigmentation of melanocytes derived from hair follicle-derived neural crest stem cells (HF-NCSCs) in vitro and study the underlying mechanisms. The HF-NCSCs were isolated from mouse whisker follicles. After radiation with high-intensity ultraviolet and NB-UVB, respectively, the cell viability by the CCK-8 assay showed gradual inhibitory effects in a dose-dependent manner, which has no apparent difference between the two modalities. The mRNA for melanogenesis factors such as tyrosinase and tyrp1 of the differentiated melanocytes increased significantly with high-intensity ultraviolet compared to the same dose of NB-UVB exposure. Furthermore, the expression of Mc1r was significantly increased by high-intensity ultraviolet in contrast to NB-UVB at the dosage of 0.5 J. By and large, these data suggest that high-intensity ultraviolet exhibited greater efficiency on the maturation of the melanocyte lineage differentiated from HF-NCSCs compared to NB-UVB with the same dose, which was probably due to the stronger stimulatory action of Mc1r. This may provide new insights into the different efficacies of high-intensity ultraviolet and NB-UVB in the treatment of vitiligo repigmentation.

  14. Translational research of adult stem cell therapy.

    PubMed

    Suzuki, Gen

    2015-11-26

    Congestive heart failure (CHF) secondary to chronic coronary artery disease is a major cause of morbidity and mortality world-wide. Its prevalence is increasing despite advances in medical and device therapies. Cell based therapies generating new cardiomyocytes and vessels have emerged as a promising treatment to reverse functional deterioration and prevent the progression to CHF. Functional efficacy of progenitor cells isolated from the bone marrow and the heart have been evaluated in preclinical large animal models. Furthermore, several clinical trials using autologous and allogeneic stem cells and progenitor cells have demonstrated their safety in humans yet their clinical relevance is inconclusive. This review will discuss the clinical therapeutic applications of three specific adult stem cells that have shown particularly promising regenerative effects in preclinical studies, bone marrow derived mesenchymal stem cell, heart derived cardiosphere-derived cell and cardiac stem cell. We will also discuss future therapeutic approaches.

  15. Sox proteins in melanocyte development and melanoma

    PubMed Central

    Harris, Melissa L.; Baxter, Laura L.; Loftus, Stacie K.; Pavan, William J.

    2010-01-01

    Over ten years has passed since the first Sox gene was implicated in melanocyte development. Since then, we have discovered that SOX5, SOX9, SOX10 and SOX18 all participate as transcription factors that affect key melanocytic genes in both regulatory and modulatory fashions. Both SOX9 and SOX10 play major roles in the establishment and normal function of the melanocyte; SOX10 has been shown to heavily influence melanocyte development and SOX9 has been implicated in melanogenesis in the adult. Despite these advances, the precise cellular and molecular details of how these SOX proteins are regulated and interact during all stages of the melanocyte life cycle remain unknown. Improper regulation of SOX9 or SOX10 is also associated with cancerous transformation, and thus understanding the normal function of SOX proteins in the melanocyte will be key to revealing how these proteins contribute to melanoma. PMID:20444197

  16. Generation of pluripotent stem cells from adult human testis.

    PubMed

    Conrad, Sabine; Renninger, Markus; Hennenlotter, Jörg; Wiesner, Tina; Just, Lothar; Bonin, Michael; Aicher, Wilhelm; Bühring, Hans-Jörg; Mattheus, Ulrich; Mack, Andreas; Wagner, Hans-Joachim; Minger, Stephen; Matzkies, Matthias; Reppel, Michael; Hescheler, Jürgen; Sievert, Karl-Dietrich; Stenzl, Arnulf; Skutella, Thomas

    2008-11-20

    Human primordial germ cells and mouse neonatal and adult germline stem cells are pluripotent and show similar properties to embryonic stem cells. Here we report the successful establishment of human adult germline stem cells derived from spermatogonial cells of adult human testis. Cellular and molecular characterization of these cells revealed many similarities to human embryonic stem cells, and the germline stem cells produced teratomas after transplantation into immunodeficient mice. The human adult germline stem cells differentiated into various types of somatic cells of all three germ layers when grown under conditions used to induce the differentiation of human embryonic stem cells. We conclude that the generation of human adult germline stem cells from testicular biopsies may provide simple and non-controversial access to individual cell-based therapy without the ethical and immunological problems associated with human embryonic stem cells.

  17. Adult Stem Cell Therapy for Stroke: Challenges and Progress

    PubMed Central

    Bang, Oh Young; Kim, Eun Hee; Cha, Jae Min; Moon, Gyeong Joon

    2016-01-01

    Stroke is one of the leading causes of death and physical disability among adults. It has been 15 years since clinical trials of stem cell therapy in patients with stroke have been conducted using adult stem cells like mesenchymal stem cells and bone marrow mononuclear cells. Results of randomized controlled trials showed that adult stem cell therapy was safe but its efficacy was modest, underscoring the need for new stem cell therapy strategies. The primary limitations of current stem cell therapies include (a) the limited source of engraftable stem cells, (b) the presence of optimal time window for stem cell therapies, (c) inherited limitation of stem cells in terms of growth, trophic support, and differentiation potential, and (d) possible transplanted cell-mediated adverse effects, such as tumor formation. Here, we discuss recent advances that overcome these hurdles in adult stem cell therapy for stroke. PMID:27733032

  18. Investigation of the effect of α-melanocyte-stimulating hormone on proliferation and early stages of differentiation of human induced pluripotent stem cells.

    PubMed

    Novosadova, E V; Manuilova, E S; Arsenyeva, E L; Andreeva, L A; Lebedeva, O S; Grivennikov, I A; Myasoedov, N F

    2016-03-01

    We have studied the influence of α-melanocyte-stimulating hormone (α-MSH) on proliferation and early stages of differentiation of human induced pluripotent stem cells (iPSc). We have demonstrated that α-MSH receptor genes are expressed in undifferentiated iPSc. The expression levels of MCR1, MCR2, and MCR3 increased at the embryoid body (EB) formation stage. The formation of neural progenitors was accompanied by elevation of MCR2, MCR3, and MCR4 expression. α-MSH had no effect on EB generation and iPSc proliferation at concentrations ranging from 1 nM to 10 μM. At the same time, α-MSH increased the generation of neural rosettes in human iPSc cultures more than twice.

  19. Atypical dermoscopic presentation of an acral congenital melanocytic nevus in an adult: parallel ridge pattern and its histologic correlation

    PubMed Central

    Roldán-Marín, Rodrigo; González-de-Cossío-Hernández, Ana Cecilia; Lammoglia-Ordiales, Lorena; Martínez-Luna, Eduwiges; Toussaint-Caire, Sonia; Ferrara, Gerardo

    2015-01-01

    Acral melanoma is the most frequent subtype in the Asian and Mexican mestizo populations. Dermoscopy is a noninvasive diagnostic technique that helps the differential diagnosis of pigmented skin lesions on acral volar skin. We, herein, present a case of acral congenital melanocytic nevus with a parallel ridge dermoscopic pattern. Since the parallel ridge pattern in a melanocytic lesion of the acral skin is classically ascribed to melanoma, the present case can be definitely labeled as “atypical” and worth of being elucidated in its histopathological correlates. PMID:26693085

  20. Differential PAX3 functions in normal skin melanocytes and melanoma cells.

    PubMed

    Medic, Sandra; Rizos, Helen; Ziman, Mel

    2011-08-12

    The PAX3 transcription factor is the key regulator of melanocyte development during embryogenesis and is also frequently found in melanoma cells. While PAX3 is known to regulate melanocyte differentiation, survival, proliferation and migration during development, it is not clear if its function is maintained in adult melanocytes and melanoma cells. To clarify this we have assessed which genes are targeted by PAX3 in these cells. We show here that similar to its roles in development, PAX3 regulates complex differentiation networks in both melanoma cells and melanocytes, in order to maintain cells as "stem" cell-like (via NES and SOX9). We show also that mediators of migration (MCAM and CSPG4) are common to both cell types but more so in melanoma cells. By contrast, PAX3-mediated regulation of melanoma cell proliferation (through TPD52) and survival (via BCL2L1 and PTEN) differs from that in melanocytes. These results suggest that by controlling cell proliferation, survival and migration as well as maintaining a less differentiated "stem" cell like phenotype, PAX3 may contribute to melanoma development and progression.

  1. Adult Mammalian Neural Stem Cells and Neurogenesis: Five Decades Later

    PubMed Central

    Bond, Allison M.; Ming, Guo-li; Song, Hongjun

    2015-01-01

    Summary Adult somatic stem cells in various organs maintain homeostatic tissue regeneration and enhance plasticity. Since its initial discovery five decades ago, investigations of adult neurogenesis and neural stem cells have led to an established and expanding field that has significantly influenced many facets of neuroscience, developmental biology and regenerative medicine. Here we review recent progress and focus on questions related to adult mammalian neural stem cells that also apply to other somatic stem cells. We further discuss emerging topics that are guiding the field toward better understanding adult neural stem cells and ultimately applying these principles to improve human health. PMID:26431181

  2. Adult stem cell-based apexogenesis

    PubMed Central

    Li, Yao; Shu, Li-Hong; Yan, Ming; Dai, Wen-Yong; Li, Jun-Jun; Zhang, Guang-Dong; Yu, Jin-Hua

    2014-01-01

    Generally, the dental pulp needs to be removed when it is infected, and root canal therapy (RCT) is usually required in which infected dental pulp is replaced with inorganic materials (paste and gutta percha). This treatment approach ultimately brings about a dead tooth. However, pulp vitality is extremely important to the tooth itself, since it provides nutrition and acts as a biosensor to detect the potential pathogenic stimuli. Despite the reported clinical success rate, RCT-treated teeth are destined to be devitalized, brittle and susceptible to postoperative fracture. Recently, the advances and achievements in the field of stem cell biology and regenerative medicine have inspired novel biological approaches to apexogenesis in young patients suffering from pulpitis or periapical periodontitis. This review mainly focuses on the benchtop and clinical regeneration of root apex mediated by adult stem cells. Moreover, current strategies for infected pulp therapy are also discussed here. PMID:25332909

  3. Modeling neural crest induction, melanocyte specification and disease-related pigmentation defects in hESCs and patient-specific iPSCs

    PubMed Central

    Mica, Yvonne; Lee, Gabsang; Chambers, Stuart M.; Tomishima, Mark; Studer, Lorenz

    2013-01-01

    SUMMARY Melanocytes are pigment-producing cells of neural crest origin responsible for protecting the skin against UV-irradiation. Pluripotent stem cell technology offers a novel approach for studying human melanocyte development and disease. Here we report that timed exposure to activators of WNT, BMP and EDN3 signaling triggers the sequential induction of neural crest and melanocyte precursor fates under dual-SMAD inhibition conditions. Using a SOX10::GFP hESC reporter line, we demonstrate that the temporal onset of WNT activation is particularly critical for human neural crest induction. Subsequent maturation of hESC-derived melanocytes yields pure populations matching the molecular and functional properties of adult melanocytes. Melanocytes from Hermansky-Pudlak and Chediak-Higashi Syndrome patient-specific iPSCs faithfully reproduce the ultrastructural features of disease-associated pigmentation defects. Our data define a highly specific requirement for WNT signaling during neural crest induction and enable the generation of pure populations of hiPSC-derived melanocytes for faithful modeling of human pigmentation disorders. PMID:23583175

  4. Adult stem cells: hopes and hypes of regenerative medicine.

    PubMed

    Dulak, Józef; Szade, Krzysztof; Szade, Agata; Nowak, Witold; Józkowicz, Alicja

    2015-01-01

    Stem cells are self-renewing cells that can differentiate into specialized cell type(s). Pluripotent stem cells, i.e. embryonic stem cells (ESC) or induced pluripotent stem cells (iPSC) differentiate into cells of all three embryonic lineages. Multipotent stem cells, like hematopoietic stem cells (HSC), can develop into multiple specialized cells in a specific tissue. Unipotent cells differentiate only into one cell type, like e.g. satellite cells of skeletal muscle. There are many examples of successful clinical applications of stem cells. Over million patients worldwide have benefited from bone marrow transplantations performed for treatment of leukemias, anemias or immunodeficiencies. Skin stem cells are used to heal severe burns, while limbal stem cells can regenerate the damaged cornea. Pluripotent stem cells, especially the patient-specific iPSC, have a tremendous therapeutic potential, but their clinical application will require overcoming numerous drawbacks. Therefore, the use of adult stem cells, which are multipotent or unipotent, can be at present a more achievable strategy. Noteworthy, some studies ascribed particular adult stem cells as pluripotent. However, despite efforts, the postulated pluripotency of such events like "spore-like cells", "very small embryonic-like stem cells" or "multipotent adult progenitor cells" have not been confirmed in stringent independent studies. Also plasticity of the bone marrow-derived cells which were suggested to differentiate e.g. into cardiomyocytes, has not been positively verified, and their therapeutic effect, if observed, results rather from the paracrine activity. Here we discuss the examples of recent studies on adult stem cells in the light of current understanding of stem cell biology.

  5. Strategies to Optimize Adult Stem Cell Therapy for Tissue Regeneration.

    PubMed

    Liu, Shan; Zhou, Jingli; Zhang, Xuan; Liu, Yang; Chen, Jin; Hu, Bo; Song, Jinlin; Zhang, Yuanyuan

    2016-06-21

    Stem cell therapy aims to replace damaged or aged cells with healthy functioning cells in congenital defects, tissue injuries, autoimmune disorders, and neurogenic degenerative diseases. Among various types of stem cells, adult stem cells (i.e., tissue-specific stem cells) commit to becoming the functional cells from their tissue of origin. These cells are the most commonly used in cell-based therapy since they do not confer risk of teratomas, do not require fetal stem cell maneuvers and thus are free of ethical concerns, and they confer low immunogenicity (even if allogenous). The goal of this review is to summarize the current state of the art and advances in using stem cell therapy for tissue repair in solid organs. Here we address key factors in cell preparation, such as the source of adult stem cells, optimal cell types for implantation (universal mesenchymal stem cells vs. tissue-specific stem cells, or induced vs. non-induced stem cells), early or late passages of stem cells, stem cells with endogenous or exogenous growth factors, preconditioning of stem cells (hypoxia, growth factors, or conditioned medium), using various controlled release systems to deliver growth factors with hydrogels or microspheres to provide apposite interactions of stem cells and their niche. We also review several approaches of cell delivery that affect the outcomes of cell therapy, including the appropriate routes of cell administration (systemic, intravenous, or intraperitoneal vs. local administration), timing for cell therapy (immediate vs. a few days after injury), single injection of a large number of cells vs. multiple smaller injections, a single site for injection vs. multiple sites and use of rodents vs. larger animal models. Future directions of stem cell-based therapies are also discussed to guide potential clinical applications.

  6. Strategies to Optimize Adult Stem Cell Therapy for Tissue Regeneration

    PubMed Central

    Liu, Shan; Zhou, Jingli; Zhang, Xuan; Liu, Yang; Chen, Jin; Hu, Bo; Song, Jinlin; Zhang, Yuanyuan

    2016-01-01

    Stem cell therapy aims to replace damaged or aged cells with healthy functioning cells in congenital defects, tissue injuries, autoimmune disorders, and neurogenic degenerative diseases. Among various types of stem cells, adult stem cells (i.e., tissue-specific stem cells) commit to becoming the functional cells from their tissue of origin. These cells are the most commonly used in cell-based therapy since they do not confer risk of teratomas, do not require fetal stem cell maneuvers and thus are free of ethical concerns, and they confer low immunogenicity (even if allogenous). The goal of this review is to summarize the current state of the art and advances in using stem cell therapy for tissue repair in solid organs. Here we address key factors in cell preparation, such as the source of adult stem cells, optimal cell types for implantation (universal mesenchymal stem cells vs. tissue-specific stem cells, or induced vs. non-induced stem cells), early or late passages of stem cells, stem cells with endogenous or exogenous growth factors, preconditioning of stem cells (hypoxia, growth factors, or conditioned medium), using various controlled release systems to deliver growth factors with hydrogels or microspheres to provide apposite interactions of stem cells and their niche. We also review several approaches of cell delivery that affect the outcomes of cell therapy, including the appropriate routes of cell administration (systemic, intravenous, or intraperitoneal vs. local administration), timing for cell therapy (immediate vs. a few days after injury), single injection of a large number of cells vs. multiple smaller injections, a single site for injection vs. multiple sites and use of rodents vs. larger animal models. Future directions of stem cell-based therapies are also discussed to guide potential clinical applications. PMID:27338364

  7. REST regulation of gene networks in adult neural stem cells

    PubMed Central

    Mukherjee, Shradha; Brulet, Rebecca; Zhang, Ling; Hsieh, Jenny

    2016-01-01

    Adult hippocampal neural stem cells generate newborn neurons throughout life due to their ability to self-renew and exist as quiescent neural progenitors (QNPs) before differentiating into transit-amplifying progenitors (TAPs) and newborn neurons. The mechanisms that control adult neural stem cell self-renewal are still largely unknown. Conditional knockout of REST (repressor element 1-silencing transcription factor) results in precocious activation of QNPs and reduced neurogenesis over time. To gain insight into the molecular mechanisms by which REST regulates adult neural stem cells, we perform chromatin immunoprecipitation sequencing and RNA-sequencing to identify direct REST target genes. We find REST regulates both QNPs and TAPs, and importantly, ribosome biogenesis, cell cycle and neuronal genes in the process. Furthermore, overexpression of individual REST target ribosome biogenesis or cell cycle genes is sufficient to induce activation of QNPs. Our data define novel REST targets to maintain the quiescent neural stem cell state. PMID:27819263

  8. REST regulation of gene networks in adult neural stem cells.

    PubMed

    Mukherjee, Shradha; Brulet, Rebecca; Zhang, Ling; Hsieh, Jenny

    2016-11-07

    Adult hippocampal neural stem cells generate newborn neurons throughout life due to their ability to self-renew and exist as quiescent neural progenitors (QNPs) before differentiating into transit-amplifying progenitors (TAPs) and newborn neurons. The mechanisms that control adult neural stem cell self-renewal are still largely unknown. Conditional knockout of REST (repressor element 1-silencing transcription factor) results in precocious activation of QNPs and reduced neurogenesis over time. To gain insight into the molecular mechanisms by which REST regulates adult neural stem cells, we perform chromatin immunoprecipitation sequencing and RNA-sequencing to identify direct REST target genes. We find REST regulates both QNPs and TAPs, and importantly, ribosome biogenesis, cell cycle and neuronal genes in the process. Furthermore, overexpression of individual REST target ribosome biogenesis or cell cycle genes is sufficient to induce activation of QNPs. Our data define novel REST targets to maintain the quiescent neural stem cell state.

  9. Brain stem auditory evoked responses in human infants and adults

    NASA Technical Reports Server (NTRS)

    Hecox, K.; Galambos, R.

    1974-01-01

    Brain stem evoked potentials were recorded by conventional scalp electrodes in infants (3 weeks to 3 years of age) and adults. The latency of one of the major response components (wave V) is shown to be a function both of click intensity and the age of the subject; this latency at a given signal strength shortens postnatally to reach the adult value (about 6 msec) by 12 to 18 months of age. The demonstrated reliability and limited variability of these brain stem electrophysiological responses provide the basis for an optimistic estimate of their usefulness as an objective method for assessing hearing in infants and adults.

  10. Narrow Band Ultraviolet B Treatment for Human Vitiligo Is Associated with Proliferation, Migration, and Differentiation of Melanocyte Precursors.

    PubMed

    Goldstein, Nathaniel B; Koster, Maranke I; Hoaglin, Laura G; Spoelstra, Nicole S; Kechris, Katerina J; Robinson, Steven E; Robinson, William A; Roop, Dennis R; Norris, David A; Birlea, Stanca A

    2015-08-01

    In vitiligo, the autoimmune destruction of epidermal melanocytes produces white spots that can be repigmented by melanocyte precursors from the hair follicles, following stimulation with UV light. We examined by immunofluorescence the distribution of melanocyte markers (C-KIT, DCT, PAX3, and TYR) coupled with markers of proliferation (KI-67) and migration (MCAM) in precursors and mature melanocytes from the hair follicle and the epidermis of untreated and narrow band UVB (NBUVB)-treated human vitiligo skin. NBUVB was associated with a significant increase in the number of melanocytes in the infundibulum and with restoration of the normal melanocyte population in the epidermis, which was lacking in the untreated vitiligo. We identified several precursor populations (melanocyte stem cells, melanoblasts, and other immature phenotypes), and progressively differentiating melanocytes, some with putative migratory and/or proliferative abilities. The primary melanocyte germ was present in the untreated and treated hair follicle bulge, whereas a possible secondary melanocyte germ composed of C-KIT+ melanocytes was found in the infundibulum and interfollicular epidermis of UV-treated vitiligo. This is an exceptional model for studying the mobilization of melanocyte stem cells in human skin. Improved understanding of this process is essential for designing better treatments for vitiligo, ultimately based on melanocyte stem cell activation and mobilization.

  11. Expansion of Multipotent Stem Cells from the Adult Human Brain

    PubMed Central

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

    2013-01-01

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

  12. Potential of adult neural stem cells in stroke therapy.

    PubMed

    Andres, Robert H; Choi, Raymond; Steinberg, Gary K; Guzman, Raphael

    2008-11-01

    Despite state-of-the-art therapy, clinical outcome after stroke remains poor, with many patients left permanently disabled and dependent on care. Stem cell therapy has evolved as a promising new therapeutic avenue for the treatment of stroke in experimental studies, and recent clinical trials have proven its feasibility and safety in patients. Replacement of damaged cells and restoration of function can be accomplished by transplantation of different cell types, such as embryonic, fetal or adult stem cells, human fetal tissue and genetically engineered cell lines. Adult neural stem cells offer the advantage of avoiding the ethical problems associated with embryonic or fetal stem cells and can be harvested as autologous grafts from the individual patients. Furthermore, stimulation of endogenous adult stem cell-mediated repair mechanisms in the brain might offer new avenues for stroke therapy without the necessity of transplantation. However, important scientific issues need to be addressed to advance our understanding of the molecular mechanisms underlying the critical steps in cell-based repair to allow the introduction of these experimental techniques into clinical practice. This review describes up-to-date experimental concepts using adult neural stem cells for the treatment of stroke.

  13. Intestinal stem cells in the adult Drosophila midgut

    SciTech Connect

    Jiang, Huaqi; Edgar, Bruce A.

    2011-11-15

    Drosophila has long been an excellent model organism for studying stem cell biology. Notably, studies of Drosophila's germline stem cells have been instrumental in developing the stem cell niche concept. The recent discovery of somatic stem cells in adult Drosophila, particularly the intestinal stem cells (ISCs) of the midgut, has established Drosophila as an exciting model to study stem cell-mediated adult tissue homeostasis and regeneration. Here, we review the major signaling pathways that regulate the self-renewal, proliferation and differentiation of Drosophila ISCs, discussing how this regulation maintains midgut homeostasis and mediates regeneration of the intestinal epithelium after injury. -- Highlights: Black-Right-Pointing-Pointer The homeostasis and regeneration of adult fly midguts are mediated by ISCs. Black-Right-Pointing-Pointer Damaged enterocytes induce the proliferation of intestinal stem cells (ISC). Black-Right-Pointing-Pointer EGFR and Jak/Stat signalings mediate compensatory ISC proliferation. Black-Right-Pointing-Pointer Notch signaling regulates ISC self-renewal and differentiation.

  14. A novel view of the adult bone marrow stem cell hierarchy and stem cell trafficking

    PubMed Central

    Ratajczak, M Z

    2015-01-01

    This review presents a novel view and working hypothesis about the hierarchy within the adult bone marrow stem cell compartment and the still-intriguing question of whether adult bone marrow contains primitive stem cells from early embryonic development, such as cells derived from the epiblast, migrating primordial germ cells or yolk sac-derived hemangioblasts. It also presents a novel view of the mechanisms that govern stem cell mobilization and homing, with special emphasis on the role of the complement cascade as a trigger for egress of hematopoietic stem cells from bone marrow into blood as well as the emerging role of novel homing factors and priming mechanisms that support stromal-derived factor 1-mediated homing of hematopoietic stem/progenitor cells after transplantation. PMID:25486871

  15. Giant congenital melanocytic nevus*

    PubMed Central

    Viana, Ana Carolina Leite; Gontijo, Bernardo; Bittencourt, Flávia Vasques

    2013-01-01

    Giant congenital melanocytic nevus is usually defined as a melanocytic lesion present at birth that will reach a diameter ≥ 20 cm in adulthood. Its incidence is estimated in <1:20,000 newborns. Despite its rarity, this lesion is important because it may associate with severe complications such as malignant melanoma, affect the central nervous system (neurocutaneous melanosis), and have major psychosocial impact on the patient and his family due to its unsightly appearance. Giant congenital melanocytic nevus generally presents as a brown lesion, with flat or mammilated surface, well-demarcated borders and hypertrichosis. Congenital melanocytic nevus is primarily a clinical diagnosis. However, congenital nevi are histologically distinguished from acquired nevi mainly by their larger size, the spread of the nevus cells to the deep layers of the skin and by their more varied architecture and morphology. Although giant congenital melanocytic nevus is recognized as a risk factor for the development of melanoma, the precise magnitude of this risk is still controversial. The estimated lifetime risk of developing melanoma varies from 5 to 10%. On account of these uncertainties and the size of the lesions, the management of giant congenital melanocytic nevus needs individualization. Treatment may include surgical and non-surgical procedures, psychological intervention and/or clinical follow-up, with special attention to changes in color, texture or on the surface of the lesion. The only absolute indication for surgery in giant congenital melanocytic nevus is the development of a malignant neoplasm on the lesion. PMID:24474093

  16. Giant congenital melanocytic nevus.

    PubMed

    Viana, Ana Carolina Leite; Gontijo, Bernardo; Bittencourt, Flávia Vasques

    2013-01-01

    Giant congenital melanocytic nevus is usually defined as a melanocytic lesion present at birth that will reach a diameter ≥ 20 cm in adulthood. Its incidence is estimated in <1:20,000 newborns. Despite its rarity, this lesion is important because it may associate with severe complications such as malignant melanoma, affect the central nervous system (neurocutaneous melanosis), and have major psychosocial impact on the patient and his family due to its unsightly appearance. Giant congenital melanocytic nevus generally presents as a brown lesion, with flat or mammilated surface, well-demarcated borders and hypertrichosis. Congenital melanocytic nevus is primarily a clinical diagnosis. However, congenital nevi are histologically distinguished from acquired nevi mainly by their larger size, the spread of the nevus cells to the deep layers of the skin and by their more varied architecture and morphology. Although giant congenital melanocytic nevus is recognized as a risk factor for the development of melanoma, the precise magnitude of this risk is still controversial. The estimated lifetime risk of developing melanoma varies from 5 to 10%. On account of these uncertainties and the size of the lesions, the management of giant congenital melanocytic nevus needs individualization. Treatment may include surgical and non-surgical procedures, psychological intervention and/or clinical follow-up, with special attention to changes in color, texture or on the surface of the lesion. The only absolute indication for surgery in giant congenital melanocytic nevus is the development of a malignant neoplasm on the lesion.

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

    PubMed

    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.

  18. Adult stem cells underlying lung regeneration.

    PubMed

    Xian, Wa; McKeon, Frank

    2012-03-01

    Despite the massive toll in human suffering imparted by degenerative lung disease, including COPD, idiopathic pulmonary fibrosis and ARDS, the scientific community has been surprisingly agnostic regarding the potential of lung tissue, and in particular the alveoli, to regenerate. However, there is circumstantial evidence in humans and direct evidence in mice that ARDS triggers robust regeneration of lung tissue rather than irreversible fibrosis. The stem cells responsible for this remarkable regenerative process has garnered tremendous attention, most recently yielding a defined set of cloned human airway stem cells marked by p63 expression but with distinct commitment to differentiated cell types typical of the upper or lower airways, the latter of which include alveoli-like structures in vitro and in vivo. These recent advances in lung regeneration and distal airway stem cells and the potential of associated soluble factors in regeneration must be harnessed for therapeutic options in chronic lung disease.

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

    PubMed

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

    2006-01-01

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

  20. Genetics of Melanocytic Nevi

    PubMed Central

    Roh, Mi Ryung; Eliades, Philip; Gupta, Sameer; Tsao, Hensin

    2015-01-01

    Melanocytic nevi are a benign clonal proliferation of cells expressing the melanocytic phenotype, with heterogeneous clinical and molecular characteristics. In this review, we discuss the genetics of nevi by salient nevi subtypes: congenital melanocytic nevi, acquired melanocytic nevi, blue nevi, and Spitz nevi. While the molecular etiology of nevi has been less thoroughly studied than melanoma, it is clear that nevi and melanoma share common driver mutations. Acquired melanocytic nevi harbor oncogenic mutations in BRAF, which is the predominant oncogene associated with melanoma. Congenital melanocytic nevi and blue nevi frequently harbor NRAS mutations and GNAQ mutations, respectively, while Spitz and atypical Spitz tumors often exhibit HRAS and kinase rearrangements. These initial “driver” mutations are thought to trigger the establishment of benign nevi. After this initial phase of cell proliferation, a senescence program is executed, causing termination of nevi growth. Only upon the emergence of additional tumorigenic alterations, which may provide an escape from oncogene-induced senescence, can malignant progression occur. Here, we review the current literature on the pathobiology and genetics of nevi in the hope that additional studies of nevi promise to inform our understanding of the transition from benign neoplasm to malignancy. PMID:26300491

  1. Comparative aspects of adult neural stem cell activity in vertebrates.

    PubMed

    Grandel, Heiner; Brand, Michael

    2013-03-01

    At birth or after hatching from the egg, vertebrate brains still contain neural stem cells which reside in specialized niches. In some cases, these stem cells are deployed for further postnatal development of parts of the brain until the final structure is reached. In other cases, postnatal neurogenesis continues as constitutive neurogenesis into adulthood leading to a net increase of the number of neurons with age. Yet, in other cases, stem cells fuel neuronal turnover. An example is protracted development of the cerebellar granular layer in mammals and birds, where neurogenesis continues for a few weeks postnatally until the granular layer has reached its definitive size and stem cells are used up. Cerebellar growth also provides an example of continued neurogenesis during adulthood in teleosts. Again, it is the granular layer that grows as neurogenesis continues and no definite adult cerebellar size is reached. Neuronal turnover is most clearly seen in the telencephalon of male canaries, where projection neurons are replaced in nucleus high vocal centre each year before the start of a new mating season--circuitry reconstruction to achieve changes of the song repertoire in these birds? In this review, we describe these and other examples of adult neurogenesis in different vertebrate taxa. We also compare the structure of the stem cell niches to find common themes in their organization despite different functions adult neurogenesis serves in different species. Finally, we report on regeneration of the zebrafish telencephalon after injury to highlight similarities and differences of constitutive neurogenesis and neuronal regeneration.

  2. Adult stem cells and their ability to differentiate.

    PubMed

    Tarnowski, Maciej; Sieron, Aleksander L

    2006-08-01

    This is a review of the current status of knowledge on adult stem cells as well as the criteria and evidence for their potential to transform into different cell types and cell lineages. Reports on stem cell sources, focusing on tissues from adult subjects, were also investigated. Numerous reports have been published on the search for early markers of both stem cells and the precursors of various cell lineages. The question is still open about the characteristics of the primary stem cell. The existing proofs and hypotheses have not yielded final solutions to this problem. From a practical point of view it is also crucial to find a minimal set of markers determining the phenotypes of the precursor cells of a particular cell lineage. Several lines of evidence seem to bring closer the day when we will be able to detect the right stem cell niche and successfully isolate precursor cells that are needed for the treatment of a particular disorder. Recent reports on cases of cancer in patients subjected to stem cell therapy are yet another controversial issue looked into in this review, although the pros and cons emerging from the results of published studies still do not provide satisfying evidence to fully understand this issue.

  3. Adherent neural stem (NS) cells from fetal and adult forebrain.

    PubMed

    Pollard, Steven M; Conti, Luciano; Sun, Yirui; Goffredo, Donato; Smith, Austin

    2006-07-01

    Stable in vitro propagation of central nervous system (CNS) stem cells would offer expanded opportunities to dissect basic molecular, cellular, and developmental processes and to model neurodegenerative disease. CNS stem cells could also provide a source of material for drug discovery assays and cell replacement therapies. We have recently reported the generation of adherent, symmetrically expandable, neural stem (NS) cell lines derived both from mouse and human embryonic stem cells and from fetal forebrain (Conti L, Pollard SM, Gorba T, Reitano E, Toselli M, Biella G, Sun Y, Sanzone S, Ying QL, Cattaneo E, Smith A. 2005. Niche-independent symmetrical self-renewal of a mammalian tissue stem cell. PLoS Biol 3(9):e283). These NS cells retain neuronal and glial differentiation potential after prolonged passaging and are transplantable. NS cells are likely to comprise the resident stem cell population within heterogeneous neurosphere cultures. Here we demonstrate that similar NS cell cultures can be established from the adult mouse brain. We also characterize the growth factor requirements for NS cell derivation and self-renewal. We discuss our current understanding of the relationship of NS cell lines to physiological progenitor cells of fetal and adult CNS.

  4. Isolation and cultivation of stem cells from adult mouse testes.

    PubMed

    Guan, Kaomei; Wolf, Frieder; Becker, Alexander; Engel, Wolfgang; Nayernia, Karim; Hasenfuss, Gerd

    2009-01-01

    The successful isolation and cultivation of spermatogonial stem cells (SSCs) as well as induction of SSCs into pluripotent stem cells will allow us to study their biological characteristics and their applications in therapeutic approaches. Here we provide step-by-step procedures on the basis of previous work in our laboratory for: the isolation of testicular cells from adolescent mice by a modified enzymatic procedure; the enrichment of undifferentiated spermatogonia by laminin selection or genetic selection using Stra8-EGFP (enhanced green fluorescent protein) transgenic mice; the cultivation and conversion of undifferentiated spermatogonia into embryonic stem-like cells, so-called multipotent adult germline stem cells (maGSCs); and characterization of these cells. Normally, it will take about 16 weeks to obtain stable maGSC lines starting from the isolation of testicular cells.

  5. Small molecule-based approaches to adult stem cell therapies.

    PubMed

    Lairson, Luke L; Lyssiotis, Costas A; Zhu, Shoutian; Schultz, Peter G

    2013-01-01

    There is considerable interest in the development of stem cell-based strategies for the treatment of a broad range of human diseases, including neurodegenerative, autoimmune, cardiovascular, and musculoskeletal diseases. To date, such regenerative approaches have focused largely on the development of cell transplantation therapies using cells derived from pluripotent embryonic stem cells (ESCs). Although there have been exciting preliminary reports describing the efficacy of ESC-derived replacement therapies, approaches involving ex vivo manipulated ESCs are hindered by issues of mutation, immune rejection, and ethical controversy. An alternative approach involves direct in vivo modulation or ex vivo expansion of endogenous adult stem cell populations using drug-like small molecules. Here we describe chemical approaches to the regulation of somatic stem cell biology that are yielding new biological insights and that may ultimately lead to innovative new medicines.

  6. Haploidentical Stem Cell Transplantation in Adult Haematological Malignancies

    PubMed Central

    Parmesar, Kevon; Raj, Kavita

    2016-01-01

    Haematopoietic stem cell transplantation is a well-established treatment option for both hematological malignancies and nonmalignant conditions such as aplastic anemia and haemoglobinopathies. For those patients lacking a suitable matched sibling or matched unrelated donor, haploidentical donors are an alternative expedient donor pool. Historically, haploidentical transplantation led to high rates of graft rejection and GVHD. Strategies to circumvent these issues include T cell depletion and management of complications thereof or T replete transplants with GVHD prophylaxis. This review is an overview of these strategies and contemporaneous outcomes for hematological malignancies in adult haploidentical stem cell transplant recipients. PMID:27313619

  7. Isolating RNA from precursor and mature melanocytes from human vitiligo and normal skin using laser capture microdissection

    PubMed Central

    Goldstein, Nathaniel B.; Koster, Maranke I.; Hoaglin, Laura G.; Wright, Michael J.; Robinson, Steven E.; Robinson, William A.; Roop, Dennis R.; Norris, David A.; Birlea, Stanca A.

    2017-01-01

    To characterize the gene expression profile of regenerated melanocytes in the narrow band UVB (NBUVB)-treated vitiligo epidermis and their precursors in the hair follicle, we present here a strategy of RNA isolation from in situ melanocytes using human frozen skin. We developed a rapid immunostaining protocol using the NKI-beteb antibody, which labels differentiated and precursor melanocytes, followed by fluorescent laser capture microdissection. This technique enabled the direct isolation, from melanocyte and adjacent keratinocyte populations, of satisfactory quality RNA that was successfully amplified and analysed by qRT-PCR. The melanocyte-specific gene transcripts TYR, DCT, TYRP1 and PMEL were significantly upregulated in our NBUVB-treated melanocyte samples as compared with the keratinocyte samples, while keratinocyte-specific genes (KRT5 and KRT14) were expressed significantly higher in the keratinocyte samples as compared with the melanocyte samples. Furthermore, in both NBUVB-treated vitiligo skin and normal skin, when bulge melanocytes were compared with epidermal melanocytes, we found significantly lower expression of melanocyte-specific genes and significantly higher expression of three melanocytic stem cell genes (SOX9, WIF1 and SFRP1), while ALCAM and ALDH1A1 transcripts did not show significant variation. We found significantly higher expression of melanocyte-specific genes in the epidermis of NBUVB-treated vitiligo, as compared to the normal skin. When comparing bulge melanocyte samples from untreated vitiligo, NBUVB-treated vitiligo and normal skin, we did not find significant differences in the expression of melanocyte-specific genes or melanocytic stem cell genes. These techniques offer valuable opportunities to study melanocytes and their precursors in vitiligo and other pigmentation disorders. PMID:27193292

  8. [Dysplastic melanocytic nevus].

    PubMed

    Bierhoff, E

    2015-02-01

    Dysplastic nevus is still a controversial entity both clinically and histologically. The occurrence of dysplastic nevus especially in the context of dysplastic nevus cell syndrome is associated with an increased risk for melanoma. The following minimal histological criteria should be fulfilled: nests of melanocytes varying in size and shape, bridging and confluent, proliferation of single melanocytes basal and suprabasal, cytoplasmic and nuclear atypia of melanocytes and subepidermal fibroplasia. The biological behavior (common nevus variant or precursor of melanoma?) is difficult to evaluate by presently available methods. The further development of new molecular biology techniques may allow a better prognosis of dysplastic nevi in an objective and reproducible manner. Against this background complete excision followed by clinical surveillance has to be recommended for the routine practice.

  9. Stem Cell-Mediated Regeneration of the Adult Brain

    PubMed Central

    Jessberger, Sebastian

    2016-01-01

    Acute or chronic injury of the adult mammalian brain is often associated with persistent functional deficits as its potential for regeneration and capacity to rebuild lost neural structures is limited. However, the discovery that neural stem cells (NSCs) persist throughout life in discrete regions of the brain, novel approaches to induce the formation of neuronal and glial cells, and recently developed strategies to generate tissue for exogenous cell replacement strategies opened novel perspectives how to regenerate the adult brain. Here, we will review recently developed approaches for brain repair and discuss future perspectives that may eventually allow for developing novel treatment strategies in acute and chronic brain injury. PMID:27781019

  10. Melanocytes in the Skin – Comparative Whole Transcriptome Analysis of Main Skin Cell Types

    PubMed Central

    Reemann, Paula; Reimann, Ene; Ilmjärv, Sten; Porosaar, Orm; Silm, Helgi; Jaks, Viljar; Vasar, Eero; Kingo, Külli; Kõks, Sulev

    2014-01-01

    Melanocytes possess several functions besides a role in pigment synthesis, but detailed characteristics of the cells are still unclear. We used whole transcriptome sequencing (RNA-Seq) to assess differential gene expression of cultivated normal human melanocytes with respect to keratinocytes, fibroblasts and whole skin. The present results reveal cultivated melanocytes as highly proliferative cells with possible stem cell-like properties. The enhanced readiness to regenerate makes melanocytes the most vulnerable cells in the skin and explains their high risk of developing into malignant melanoma. PMID:25545474

  11. Melanocytes in the skin--comparative whole transcriptome analysis of main skin cell types.

    PubMed

    Reemann, Paula; Reimann, Ene; Ilmjärv, Sten; Porosaar, Orm; Silm, Helgi; Jaks, Viljar; Vasar, Eero; Kingo, Külli; Kõks, Sulev

    2014-01-01

    Melanocytes possess several functions besides a role in pigment synthesis, but detailed characteristics of the cells are still unclear. We used whole transcriptome sequencing (RNA-Seq) to assess differential gene expression of cultivated normal human melanocytes with respect to keratinocytes, fibroblasts and whole skin. The present results reveal cultivated melanocytes as highly proliferative cells with possible stem cell-like properties. The enhanced readiness to regenerate makes melanocytes the most vulnerable cells in the skin and explains their high risk of developing into malignant melanoma.

  12. Pericytes, integral components of adult hematopoietic stem cell niches.

    PubMed

    Sá da Bandeira, D; Casamitjana, J; Crisan, M

    2017-03-01

    The interest in perivascular cells as a niche for adult hematopoietic stem cells (HSCs) is significantly growing. In the adult bone marrow (BM), perivascular cells and HSCs cohabit. Among perivascular cells, pericytes are precursors of mesenchymal stem/stromal cells (MSCs) that are capable of differentiating into osteoblasts, adipocytes and chondrocytes. In situ, pericytes are recognised by their localisation to the abluminal side of the blood vessel wall and closely associated with endothelial cells, in combination with the expression of markers such as CD146, neural glial 2 (NG2), platelet derived growth factor receptor β (PDGFRβ), α-smooth muscle actin (α-SMA), nestin (Nes) and/or leptin receptor (LepR). However, not all pericytes share a common phenotype: different immunophenotypes can be associated with distinct mesenchymal features, including hematopoietic support. In adult BM, arteriolar and sinusoidal pericytes control HSC behaviour, maintenance, quiescence and trafficking through paracrine effects. Different groups identified and characterized hematopoietic supportive pericyte subpopulations using various markers and mouse models. In this review, we summarize recent work performed by others to understand the role of the perivascular niche in the biology of HSCs in adults, as well as their importance in the development of therapies.

  13. Cellular origin and developmental mechanisms during the formation of skin melanocytes

    SciTech Connect

    Ernfors, Patrik

    2010-05-01

    Melanocytes are derived from the neural crest (NC), which are transient multipotent cells arising by delamination from the developing dorsal neural tube. During recent years, signaling systems and molecular mechanisms of melanocyte development have been studied in detail, but the exact diversification of the NC into melanocytes and how they migrate, expand and disperse in the skin have not been fully understood. The recent finding that Schwann cell precursors (SCPs) of the growing nerve represents a stem cell niche from which various cell types, including Schwann cells, endoneural fibroblasts and melanocytes arise has exposed new knowledge on the cellular basis for melanocyte development. This opens for the identification of new factors and reinterpretation of old data on cell fate instructive, proliferative, survival and cell homing factors participating in melanocyte development.

  14. Paracrine Secreted Frizzled-Related Protein 4 Inhibits Melanocytes Differentiation in Hair Follicle

    PubMed Central

    Guo, Haiying; Lei, Mingxing; Li, Yuhong; Liu, Yingxin; Tang, Yinhong; Xing, Yizhan; Deng, Fang

    2017-01-01

    Wnt signaling plays crucial role in regulating melanocyte stem cells/melanocyte differentiation in the hair follicle. However, how the Wnt signaling is balanced to be overactivated to control follicular melanocytes behavior remains unknown. Here, by using immunofluorescence staining, we showed that secreted frizzled-related protein 4 (sFRP4) is preferentially expressed in the skin epidermal cells rather than in melanocytes. By overexpression of sFRP4 in skin cells in vivo and in vitro, we found that sFRP4 attenuates activation of Wnt signaling, resulting in decrease of melanocytes differentiation in the regenerating hair follicle. Our findings unveiled a new regulator that involves modulating melanocytes differentiation through a paracrine mechanism in hair follicle, supplying a hope for potential therapeutic application to treat skin pigmentation disorders. PMID:28337220

  15. Immune Influence on Adult Neural Stem Cell Regulation and Function

    PubMed Central

    Carpentier, Pamela A.; Palmer, Theo D.

    2009-01-01

    Neural stem cells (NSCs) lie at the heart of central nervous system development and repair, and deficiency or dysregulation of NSCs or their progeny can have significant consequences at any stage of life. Immune signaling is emerging as one of the influential variables that define resident NSC behavior. Perturbations in local immune signaling accompany virtually every injury or disease state and signaling cascades that mediate immune activation, resolution, or chronic persistence influence resident stem and progenitor cells. Some aspects of immune signaling are beneficial, promoting intrinsic plasticity and cell replacement, while others appear to inhibit the very type of regenerative response that might restore or replace neural networks lost in injury or disease. Here we review known and speculative roles that immune signaling plays in the postnatal and adult brain, focusing on how environments encountered in disease or injury may influence the activity and fate of endogenous or transplanted NSCs. PMID:19840551

  16. MITF accurately highlights epidermal melanocytes in atypical intraepidermal melanocytic proliferations.

    PubMed

    Nybakken, Grant E; Sargen, Michael; Abraham, Ronnie; Zhang, Paul J; Ming, Michael; Xu, Xiaowei

    2013-02-01

    Atypical intraepidermal melanocytic proliferations (AIMP) have random cytologic atypia and other histologic features that are concerning for malignancy and often require immunohistochemistry to differentiate from melanoma in situ. Immunostaining with S100, Melan-A, and microphthalmia-associated transcription factor (MITF) was performed for 49 morphologically well-characterized AIMP lesions. The percentage of cells in the basal layer of the epidermis that were identified as melanocytes by immunohistochemistry was compared with the percentage observed by morphology on hematoxylin and eosin staining, which is the gold standard stain for identifying cytologic atypia within an AIMP. Melan-A estimated the highest percentage of melanocytes and S100 the fewest in 47 of the 49 lesions examined. The estimated percentage of melanocytes was 23.3% (95% confidence interval: 18.6-28.1; P < 0.001) higher for Melan-A compared with hematoxylin and eosin staining. Melanocyte estimates were similar for hematoxylin and eosin and MITF (P = 0.15) although S100 estimated 21.8% (95% confidence interval: -27.2 to -16.4; P < 0.001) fewer melanocytes than hematoxylin and eosin. Melan-A staining produces higher estimates of epidermal melanocytes than S100 and MITF, which may increase the likelihood of diagnosing melanoma in situ. In contrast, melanoma in situ may be underdiagnosed with the use of S100, which results in lower estimates of melanocytes than the other 2 immunostains. Therefore, the best immunohistochemical marker for epidermal melanocytes is MITF.

  17. Melanocytes and Their Diseases

    PubMed Central

    Yamaguchi, Yuji; Hearing, Vincent J.

    2014-01-01

    Human melanocytes are distributed not only in the epidermis and in hair follicles but also in mucosa, cochlea (ear), iris (eye), and mesencephalon (brain) among other tissues. Melanocytes, which are derived from the neural crest, are unique in that they produce eu-/pheo-melanin pigments in unique membrane-bound organelles termed melanosomes, which can be divided into four stages depending on their degree of maturation. Pigmentation production is determined by three distinct elements: enzymes involved in melanin synthesis, proteins required for melanosome structure, and proteins required for their trafficking and distribution. Many genes are involved in regulating pigmentation at various levels, and mutations in many of them cause pigmentary disorders, which can be classified into three types: hyperpigmentation (including melasma), hypopigmentation (including oculocutaneous albinism [OCA]), and mixed hyper-/hypopigmentation (including dyschromatosis symmetrica hereditaria). We briefly review vitiligo as a representative of an acquired hypopigmentation disorder. PMID:24789876

  18. Retentive multipotency of adult dorsal root ganglia stem cells.

    PubMed

    Singh, Rabindra P; Cheng, Ying-Hua; Nelson, Paul; Zhou, Feng C

    2009-01-01

    Preservation of neural stem cells (NSCs) in the adult peripheral nervous system (PNS) has recently been confirmed. However, it is not clear whether peripheral NSCs possess predestined, bona fide phenotypes or a response to innate developmental cues. In this study, we first demonstrated the longevity, multipotency, and high fidelity of sensory features of postmigrating adult dorsal root ganglia (aDRG) stem cells. Derived from aDRG and after 4-5 years in culture without dissociating, the aDRG NSCs were found capable of proliferation, expressing neuroepithelial, neuronal, and glial markers. Remarkably, these aDRG NSCs expressed sensory neuronal markers vesicular glutamate transporter 2 (VGluT2--glutamate terminals), transient receptor potential vanilloid 1 (TrpV1--capsaicin sensitive), phosphorylated 200 kDa neurofilaments (pNF200--capsaicin insensitive, myelinated), and the serotonin transporter (5-HTT), which normally is transiently expressed in developing DRG. Furthermore, in response to neurotrophins, the aDRG NSCs enhanced TrpV1 expression upon exposure to nerve growth factor (NGF), but not to brain-derived neurotrophic factor (BDNF). On the contrary, BDNF increased the expression of NeuN. Third, the characterization of aDRG NSCs was demonstrated by transplantation of red fluorescent-expressing aDRG NSCs into injured spinal cord. These cells expressed nestin, Hu, and beta-III-tubulin (immature neuronal markers), GFAP (astrocyte marker) as well as sensory neural marker TrpV1 (capsaicin sensitive) and pNF200 (mature, capsaicin insensitive, myelinated). Our results demonstrated that the postmigrating neural crest adult DRG stem cells not only preserved their multipotency but also were retentive in sensory potency despite the age and long-term ex vivo status.

  19. Novel Adult Stem Cells for Peripheral Nerve Regeneration

    DTIC Science & Technology

    2012-09-01

    Circulation 103, 882–888 (2001). 52. Biernaskie, J. et al. SKPs derive from hair follicle precursors and exhibit properties of adult dermal stem cells...3). * indicates significant difference between indicated groups using Holm’s t- test . (P < 0.01). (l–s) Immunostaining of isolated sm-mHC − cells...and the tissue from which the cells were derived using student’s t- test (P < 0.05). † indicates significant difference between inferior vena cava and

  20. Differentiated human stem cells resemble fetal, not adult, β cells.

    PubMed

    Hrvatin, Sinisa; O'Donnell, Charles W; Deng, Francis; Millman, Jeffrey R; Pagliuca, Felicia Walton; DiIorio, Philip; Rezania, Alireza; Gifford, David K; Melton, Douglas A

    2014-02-25

    Human pluripotent stem cells (hPSCs) have the potential to generate any human cell type, and one widely recognized goal is to make pancreatic β cells. To this end, comparisons between differentiated cell types produced in vitro and their in vivo counterparts are essential to validate hPSC-derived cells. Genome-wide transcriptional analysis of sorted insulin-expressing (INS(+)) cells derived from three independent hPSC lines, human fetal pancreata, and adult human islets points to two major conclusions: (i) Different hPSC lines produce highly similar INS(+) cells and (ii) hPSC-derived INS(+) (hPSC-INS(+)) cells more closely resemble human fetal β cells than adult β cells. This study provides a direct comparison of transcriptional programs between pure hPSC-INS(+) cells and true β cells and provides a catalog of genes whose manipulation may convert hPSC-INS(+) cells into functional β cells.

  1. Positional identity of adult stem cells in salamander limb regeneration.

    PubMed

    Kumar, Anoop; Gates, Phillip B; Brockes, Jeremy P

    2007-01-01

    Limb regeneration in larval and adult salamanders proceeds from a mound of mesenchymal stem cells called the limb blastema. The blastema gives rise just to those structures distal to its level of origin, and this property of positional identity is reset to more proximal values by treatment with retinoic acid. We have identified a cell surface protein, called Prod1/CD59, which appears to be a determinant of proximodistal identity. Prod1 is expressed in an exponential gradient in an adult limb as determined by detection of both mRNA and immunoreactive protein. Prod1 protein is up-regulated after treatment of distal blastemas with RA and this is particularly marked in cells of the dermis. These cells have previously been implicated in pattern formation during limb regeneration.

  2. The longest telomeres: a general signature of adult stem cell compartments

    PubMed Central

    Flores, Ignacio; Canela, Andres; Vera, Elsa; Tejera, Agueda; Cotsarelis, George; Blasco, María A.

    2008-01-01

    Identification of adult stem cells and their location (niches) is of great relevance for regenerative medicine. However, stem cell niches are still poorly defined in most adult tissues. Here, we show that the longest telomeres are a general feature of adult stem cell compartments. Using confocal telomere quantitative fluorescence in situ hybridization (telomapping), we find gradients of telomere length within tissues, with the longest telomeres mapping to the known stem cell compartments. In mouse hair follicles, we show that cells with the longest telomeres map to the known stem cell compartments, colocalize with stem cell markers, and behave as stem cells upon treatment with mitogenic stimuli. Using K15-EGFP reporter mice, which mark hair follicle stem cells, we show that GFP-positive cells have the longest telomeres. The stem cell compartments in small intestine, testis, cornea, and brain of the mouse are also enriched in cells with the longest telomeres. This constitutes the description of a novel general property of adult stem cell compartments. Finally, we make the novel finding that telomeres shorten with age in different mouse stem cell compartments, which parallels a decline in stem cell functionality, suggesting that telomere loss may contribute to stem cell dysfunction with age. PMID:18283121

  3. Adult stem cells for cardiac repair: a choice between skeletal myoblasts and bone marrow stem cells.

    PubMed

    Ye, Lei; Haider, Husnain Kh; Sim, Eugene K W

    2006-01-01

    The real promise of a stem cell-based approach for cardiac regeneration and repair lies in the promotion of myogenesis and angiogenesis at the site of the cell graft to achieve both structural and functional benefits. Despite all of the progress and promise in this field, many unanswered questions remain; the answers to these questions will provide the much-needed breakthrough to harness the real benefits of cell therapy for the heart in the clinical perspective. One of the major issues is the choice of donor cell type for transplantation. Multiple cell types with varying potentials have been assessed for their ability to repopulate the infarcted myocardium; however, only the adult stem cells, that is, skeletal myoblasts (SkM) and bone marrow-derived stem cells (BMC), have been translated from the laboratory bench to clinical use. Which of these two cell types will provide the best option for clinical application in heart cell therapy remains arguable. With results pouring in from the long-term follow-ups of previously conducted phase I clinical studies, and with the onset of phase II clinical trials involving larger population of patients, transplantation of stem cells as a sole therapy without an adjunct conventional revascularization procedure will provide a deeper insight into the effectiveness of this approach. The present article discusses the pros and cons of using SkM and BMC individually or in combination for cardiac repair, and critically analyzes the progress made with each cell type.

  4. From adult stem cells to cancer stem cells: Oct-4 Gene, cell-cell communication, and hormones during tumor promotion.

    PubMed

    Trosko, James E

    2006-11-01

    Carcinogenesis is characterized by "initiation," "promotion," and "progression" phases. The "stem cell theory" and "de-differentiation" theories are used to explain the origin of cancer. Growth control for stem cells, which lack functional gap junctional intercellular communication (GJIC), involves negative soluble or niche factors, while for progenitor cells, it involves GJIC. Tumor promoters, hormones, and growth factors inhibit GJIC reversibly. Oncogenes stably inhibit GJIC. Cancer cells, which lack growth control and the ability to terminally differentiate and to apoptose, lack GJIC. The Oct3/4 gene, a POU (Pit-Oct-Unc) family of transcription factors was thought to be expressed only in embryonic stem cells and in tumor cells. With the availability of normal adult human stem cells, tests for the expression of Oct3/4 gene and the stem cell theory in human carcinogenesis became possible. Human breast, liver, pancreas, kidney, mesenchyme, and gastric stem cells, HeLa and MCF-7 cells, and canine tumors were tested with antibodies and polymerase chain reaction (PCR) primers for Oct3/4. Adult human breast stem cells, immortalized nontumorigenic and tumor cell lines, but not the normal differentiated cells, expressed Oct3/4. Adult human differentiated cells lose their Oct-4 expression. Oct3/4 is expressed in a few cells found in the basal layer of human skin epidermis. The data demonstrate that normal adult stem cells and cancer stem cells maintain expression of Oct3/4, consistent with the stem cell hypothesis of carcinogenesis. These Oct-4 positive cells might represent the "cancer stem cells." A strategy to target "cancer stem cells" is to suppress the Oct-4 gene in order to cause the cells to differentiate.

  5. A signet-ring cell melanoma arising from a medium-sized congenital melanocytic nevus in an adult: A case report and literature review.

    PubMed

    Tajima, Shogo; Koda, Kenji

    2015-07-01

    Patients with congenital nevus, especially giant congenital melanocytic nevus (CMN) measuring >20 cm, are known to be at elevated risk of developing melanomas, especially during the first and second decades of life. Melanomas rarely develop in patients with small and medium-sized CMNs, but if they do, they occur during the fourth and fifth decades of life. We present a case of a rapidly enlarging signet-ring cell melanoma (over 3 months) that arose from a medium-sized CMN in a 57-year-old Japanese man. Only 11 other cases of signet-ring cell melanomas at the primary site have been reported. On the basis of morphology alone, it is difficult to diagnose a nodule appearing in a CMN as a signet-ring cell melanoma, because even a benign melanocytic nevus can appear as signet-ring cell morphology. Moreover, a rapidly growing proliferative nodule (PN) more often develops in a CMN than melanoma; PNs may at times exhibit enough atypia to be comparable to melanomas. In our case, loss of p16 expression in the melanoma distinguished it from the nevus cells and was helpful in making the correct diagnosis. Clinical information, such as the patient's age, was also useful in establishing the diagnosis.

  6. Oct4 expression in adult human stem cells: evidence in support of the stem cell theory of carcinogenesis.

    PubMed

    Tai, Mei-Hui; Chang, Chia-Cheng; Kiupel, Matti; Webster, Joshua D; Olson, L Karl; Trosko, James E

    2005-02-01

    The Oct3/4 gene, a POU family transcription factor, has been noted as being specifically expressed in embryonic stem cells and in tumor cells but not in cells of differentiated tissues. With the ability to isolate adult human stem cells it became possible to test for the expression of Oct3/4 gene in adult stem cells and to test the stem cell theory of carcinogenesis. Using antibodies and PCR primers we tested human breast, liver, pancreas, kidney, mesenchyme and gastric stem cells, the cancer cell lines HeLa and MCF-7 and human, dog and rat tumors for Oct4 expression. The results indicate that adult human stem cells, immortalized non-tumorigenic cells and tumor cells and cell lines, but not differentiated cells, express Oct4. Oct4 is expressed in a few cells found in the basal layer of human skin epidermis. The data demonstrate that adult stem cells maintain expression of Oct4, consistent with the stem cell hypothesis of carcinogenesis.

  7. Endothelin-1 is a transcriptional target of p53 in epidermal keratinocytes and regulates UV induced melanocyte homeostasis

    PubMed Central

    Hyter, Stephen; Coleman, Daniel J.; Ganguli-Indra, Gitali; Merrill, Gary F.; Ma, Steven; Yanagisawa, Masashi; Indra, Arup K.

    2013-01-01

    Summary Keratinocytes contribute to melanocyte activity by influencing their microenvironment, in part, through secretion of paracrine factors. Here we discovered that p53 directly regulates Edn1 expression in epidermal keratinocytes and controls UV-induced melanocyte homeostasis. Selective ablation of EDN1 in murine epidermis (EDN1ep−/−) does not alter melanocyte homeostasis in newborn skin but decreases dermal melanocytes in adult skin. Results showed that keratinocytic EDN1 in a non-cell autonomous manner controls melanocyte proliferation, migration, DNA damage and apoptosis after UVB irradiation. Expression of other keratinocyte derived paracrine factors did not compensate for the loss of EDN1. Topical treatment with EDN1 receptor (EDNRB) antagonist BQ788 abrogated UV induced melanocyte activation and recapitulated the phenotype seen in EDN1ep−/− mice. Altogether, present studies establish an essential role of EDN1 in epidermal keratinocytes to mediate UV induced melanocyte homeostasis in vivo. PMID:23279852

  8. Catalog of gene expression in adult neural stem cells and their in vivo microenvironment

    SciTech Connect

    Williams, Cecilia; Wirta, Valtteri; Meletis, Konstantinos; Wikstroem, Lilian; Carlsson, Leif; Frisen, Jonas; Lundeberg, Joakim . E-mail: joakim.lundeberg@biotech.kth.se

    2006-06-10

    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.

  9. Axonal control of the adult neural stem cell niche.

    PubMed

    Tong, Cheuk Ka; Chen, Jiadong; Cebrián-Silla, Arantxa; Mirzadeh, Zaman; Obernier, Kirsten; Guinto, Cristina D; Tecott, Laurence H; García-Verdugo, Jose Manuel; Kriegstein, Arnold; Alvarez-Buylla, Arturo

    2014-04-03

    The ventricular-subventricular zone (V-SVZ) is an extensive germinal niche containing neural stem cells (NSCs) in the walls of the lateral ventricles of the adult brain. How the adult brain's neural activity influences the behavior of adult NSCs remains largely unknown. We show that serotonergic (5HT) axons originating from a small group of neurons in the raphe form an extensive plexus on most of the ventricular walls. Electron microscopy revealed intimate contacts between 5HT axons and NSCs (B1) or ependymal cells (E1) and these cells were labeled by a transsynaptic viral tracer injected into the raphe. B1 cells express the 5HT receptors 2C and 5A. Electrophysiology showed that activation of these receptors in B1 cells induced small inward currents. Intraventricular infusion of 5HT2C agonist or antagonist increased or decreased V-SVZ proliferation, respectively. These results indicate that supraependymal 5HT axons directly interact with NSCs to regulate neurogenesis via 5HT2C.

  10. Live Imaging of Adult Neural Stem Cells in Rodents

    PubMed Central

    Ortega, Felipe; Costa, Marcos R.

    2016-01-01

    The generation of cells of the neural lineage within the brain is not restricted to early development. New neurons, oligodendrocytes, and astrocytes are produced in the adult brain throughout the entire murine life. However, despite the extensive research performed in the field of adult neurogenesis during the past years, fundamental questions regarding the cell biology of adult neural stem cells (aNSCs) remain to be uncovered. For instance, it is crucial to elucidate whether a single aNSC is capable of differentiating into all three different macroglial cell types in vivo or these distinct progenies constitute entirely separate lineages. Similarly, the cell cycle length, the time and mode of division (symmetric vs. asymmetric) that these cells undergo within their lineage progression are interesting questions under current investigation. In this sense, live imaging constitutes a valuable ally in the search of reliable answers to the previous questions. In spite of the current limitations of technology new approaches are being developed and outstanding amount of knowledge is being piled up providing interesting insights in the behavior of aNSCs. Here, we will review the state of the art of live imaging as well as the alternative models that currently offer new answers to critical questions. PMID:27013941

  11. Axonal Control of the Adult Neural Stem Cell Niche

    PubMed Central

    Tong, Cheuk Ka; Chen, Jiadong; Cebrián-Silla, Arantxa; Mirzadeh, Zaman; Obernier, Kirsten; Guinto, Cristina D.; Tecott, Laurence H.; García-Verdugo, Jose Manuel; Kriegstein, Arnold; Alvarez-Buylla, Arturo

    2014-01-01

    SUMMARY The ventricular-subventricular zone (V-SVZ) is an extensive germinal niche containing neural stem cells (NSC) in the walls of the lateral ventricles of the adult brain. How the adult brain’s neural activity influences the behavior of adult NSCs remains largely unknown. We show that serotonergic (5HT) axons originating from a small group of neurons in the raphe form an extensive plexus on most of the ventricular walls. Electron microscopy revealed intimate contacts between 5HT axons and NSCs (B1) or ependymal cells (E1) and these cells were labeled by a transsynaptic viral tracer injected into the raphe. B1 cells express the 5HT receptors 2C and 5A. Electrophysiology showed that activation of these receptors in B1 cells induced small inward currents. Intraventricular infusion of 5HT2C agonist or antagonist increased or decreased V-SVZ proliferation, respectively. These results indicate that supraependymal 5HT axons directly interact with NSCs to regulate neurogenesis via 5HT2C. PMID:24561083

  12. Visualization of adult stem cells within their niches using the Drosophila germline as a model system.

    PubMed

    König, Annekatrin; Shcherbata, Halyna R

    2013-01-01

    The germaria of the fruit fly Drosophila melanogaster present an excellent model to study germline stem cell-niche interactions. Two to three adult stem cells are surrounded by a number of somatic cells that form the niche. Here we describe how Drosophilae germaria can be dissected and specifically immuno-stained to allow for identification and analysis of both the adult stem cells and their somatic niche cells.

  13. Pirin Inhibits Cellular Senescence in Melanocytic Cells

    PubMed Central

    Licciulli, Silvia; Luise, Chiara; Scafetta, Gaia; Capra, Maria; Giardina, Giuseppina; Nuciforo, Paolo; Bosari, Silvano; Viale, Giuseppe; Mazzarol, Giovanni; Tonelli, Chiara; Lanfrancone, Luisa; Alcalay, Myriam

    2011-01-01

    Cellular senescence has been widely recognized as a tumor suppressing mechanism that acts as a barrier to cancer development after oncogenic stimuli. A prominent in vivo model of the senescence barrier is represented by nevi, which are composed of melanocytes that, after an initial phase of proliferation induced by activated oncogenes (most commonly BRAF), are blocked in a state of cellular senescence. Transformation to melanoma occurs when genes involved in controlling senescence are mutated or silenced and cells reacquire the capacity to proliferate. Pirin (PIR) is a highly conserved nuclear protein that likely functions as a transcriptional regulator whose expression levels are altered in different types of tumors. We analyzed the expression pattern of PIR in adult human tissues and found that it is expressed in melanocytes and has a complex pattern of regulation in nevi and melanoma: it is rarely detected in mature nevi, but is expressed at high levels in a subset of melanomas. Loss of function and overexpression experiments in normal and transformed melanocytic cells revealed that PIR is involved in the negative control of cellular senescence and that its expression is necessary to overcome the senescence barrier. Our results suggest that PIR may have a relevant role in melanoma progression. PMID:21514450

  14. Regulation of seminiferous tubule-associated stem Leydig cells in adult rat testes.

    PubMed

    Li, Xiaoheng; Wang, Zhao; Jiang, Zhenming; Guo, Jingjing; Zhang, Yuxi; Li, Chenhao; Chung, Jinyong; Folmer, Janet; Liu, June; Lian, Qingquan; Ge, Renshan; Zirkin, Barry R; Chen, Haolin

    2016-03-08

    Testicular Leydig cells are the primary source of testosterone in males. Adult Leydig cells have been shown to arise from stem cells present in the neonatal testis. Once established, adult Leydig cells turn over only slowly during adult life, but when these cells are eliminated experimentally from the adult testis, new Leydig cells rapidly reappear. As in the neonatal testis, stem cells in the adult testis are presumed to be the source of the new Leydig cells. As yet, the mechanisms involved in regulating the proliferation and differentiation of these stem cells remain unknown. We developed a unique in vitro system of cultured seminiferous tubules to assess the ability of factors from the seminiferous tubules to regulate the proliferation of the tubule-associated stem cells, and their subsequent entry into the Leydig cell lineage. The proliferation of the stem Leydig cells was stimulated by paracrine factors including Desert hedgehog (DHH), basic fibroblast growth factor (FGF2), platelet-derived growth factor (PDGF), and activin. Suppression of proliferation occurred with transforming growth factor β (TGF-β). The differentiation of the stem cells was regulated positively by DHH, lithium- induced signaling, and activin, and negatively by TGF-β, PDGFBB, and FGF2. DHH functioned as a commitment factor, inducing the transition of stem cells to the progenitor stage and thus into the Leydig cell lineage. Additionally, CD90 (Thy1) was found to be a unique stem cell surface marker that was used to obtain purified stem cells by flow cytometry.

  15. Multipotent (adult) and pluripotent stem cells for heart regeneration: what are the pros and cons?

    PubMed

    Liao, Song-Yan; Tse, Hung-Fat

    2013-12-24

    Heart failure after myocardial infarction is the leading cause of mortality and morbidity worldwide. Existing medical and interventional therapies can only reduce the loss of cardiomyocytes during myocardial infarction but are unable to replenish the permanent loss of cardiomyocytes after the insult, which contributes to progressive pathological left ventricular remodeling and progressive heart failure. As a result, cell-based therapies using multipotent (adult) stem cells and pluripotent stem cells (embryonic stem cells or induced pluripotent stem cells) have been explored as potential therapeutic approaches to restore cardiac function in heart failure. Nevertheless, the optimal cell type with the best therapeutic efficacy and safety for heart regeneration is still unknown. In this review, the potential pros and cons of different types of multipotent (adult) stem cells and pluripotent stem cells that have been investigated in preclinical and clinical studies are reviewed, and the future perspective of stem cell-based therapy for heart regeneration is discussed.

  16. Neurodevelopment. Live imaging of adult neural stem cell behavior in the intact and injured zebrafish brain.

    PubMed

    Barbosa, Joana S; Sanchez-Gonzalez, Rosario; Di Giaimo, Rossella; Baumgart, Emily Violette; Theis, Fabian J; Götz, Magdalena; Ninkovic, Jovica

    2015-05-15

    Adult neural stem cells are the source for restoring injured brain tissue. We used repetitive imaging to follow single stem cells in the intact and injured adult zebrafish telencephalon in vivo and found that neurons are generated by both direct conversions of stem cells into postmitotic neurons and via intermediate progenitors amplifying the neuronal output. We observed an imbalance of direct conversion consuming the stem cells and asymmetric and symmetric self-renewing divisions, leading to depletion of stem cells over time. After brain injury, neuronal progenitors are recruited to the injury site. These progenitors are generated by symmetric divisions that deplete the pool of stem cells, a mode of neurogenesis absent in the intact telencephalon. Our analysis revealed changes in the behavior of stem cells underlying generation of additional neurons during regeneration.

  17. Sox10(+) adult stem cells contribute to biomaterial encapsulation and microvascularization.

    PubMed

    Wang, Dong; Wang, Aijun; Wu, Fan; Qiu, Xuefeng; Li, Ye; Chu, Julia; Huang, Wen-Chin; Xu, Kang; Gong, Xiaohua; Li, Song

    2017-01-10

    Implanted biomaterials and biomedical devices generally induce foreign body reaction and end up with encapsulation by a dense avascular fibrous layer enriched in extracellular matrix. Fibroblasts/myofibroblasts are thought to be the major cell type involved in encapsulation, but it is unclear whether and how stem cells contribute to this process. Here we show, for the first time, that Sox10(+) adult stem cells contribute to both encapsulation and microvessel formation. Sox10(+) adult stem cells were found sparsely in the stroma of subcutaneous loose connective tissues. Upon subcutaneous biomaterial implantation, Sox10(+) stem cells were activated and recruited to the biomaterial scaffold, and differentiated into fibroblasts and then myofibroblasts. This differentiation process from Sox10(+) stem cells to myofibroblasts could be recapitulated in vitro. On the other hand, Sox10(+) stem cells could differentiate into perivascular cells to stabilize newly formed microvessels. Sox10(+) stem cells and endothelial cells in three-dimensional co-culture self-assembled into microvessels, and platelet-derived growth factor had chemotactic effect on Sox10(+) stem cells. Transplanted Sox10(+) stem cells differentiated into smooth muscle cells to stabilize functional microvessels. These findings demonstrate the critical role of adult stem cells in tissue remodeling and unravel the complexity of stem cell fate determination.

  18. Sox10+ adult stem cells contribute to biomaterial encapsulation and microvascularization

    PubMed Central

    Wang, Dong; Wang, Aijun; Wu, Fan; Qiu, Xuefeng; Li, Ye; Chu, Julia; Huang, Wen-Chin; Xu, Kang; Gong, Xiaohua; Li, Song

    2017-01-01

    Implanted biomaterials and biomedical devices generally induce foreign body reaction and end up with encapsulation by a dense avascular fibrous layer enriched in extracellular matrix. Fibroblasts/myofibroblasts are thought to be the major cell type involved in encapsulation, but it is unclear whether and how stem cells contribute to this process. Here we show, for the first time, that Sox10+ adult stem cells contribute to both encapsulation and microvessel formation. Sox10+ adult stem cells were found sparsely in the stroma of subcutaneous loose connective tissues. Upon subcutaneous biomaterial implantation, Sox10+ stem cells were activated and recruited to the biomaterial scaffold, and differentiated into fibroblasts and then myofibroblasts. This differentiation process from Sox10+ stem cells to myofibroblasts could be recapitulated in vitro. On the other hand, Sox10+ stem cells could differentiate into perivascular cells to stabilize newly formed microvessels. Sox10+ stem cells and endothelial cells in three-dimensional co-culture self-assembled into microvessels, and platelet-derived growth factor had chemotactic effect on Sox10+ stem cells. Transplanted Sox10+ stem cells differentiated into smooth muscle cells to stabilize functional microvessels. These findings demonstrate the critical role of adult stem cells in tissue remodeling and unravel the complexity of stem cell fate determination. PMID:28071739

  19. Transcriptional profiling of adult neural stem-like cells from the human brain.

    PubMed

    Sandberg, Cecilie Jonsgar; Vik-Mo, Einar O; Behnan, Jinan; Helseth, Eirik; Langmoen, Iver A

    2014-01-01

    There is a great potential for the development of new cell replacement strategies based on adult human neural stem-like cells. However, little is known about the hierarchy of cells and the unique molecular properties of stem- and progenitor cells of the nervous system. Stem cells from the adult human brain can be propagated and expanded in vitro as free floating neurospheres that are capable of self-renewal and differentiation into all three cell types of the central nervous system. Here we report the first global gene expression study of adult human neural stem-like cells originating from five human subventricular zone biopsies (mean age 42, range 33-60). Compared to adult human brain tissue, we identified 1,189 genes that were significantly up- and down-regulated in adult human neural stem-like cells (1% false discovery rate). We found that adult human neural stem-like cells express stem cell markers and have reduced levels of markers that are typical of the mature cells in the nervous system. We report that the genes being highly expressed in adult human neural stem-like cells are associated with developmental processes and the extracellular region of the cell. The calcium signaling pathway and neuroactive ligand-receptor interactions are enriched among the most differentially regulated genes between adult human neural stem-like cells and adult human brain tissue. We confirmed the expression of 10 of the most up-regulated genes in adult human neural stem-like cells in an additional sample set that included adult human neural stem-like cells (n = 6), foetal human neural stem cells (n = 1) and human brain tissues (n = 12). The NGFR, SLITRK6 and KCNS3 receptors were further investigated by immunofluorescence and shown to be heterogeneously expressed in spheres. These receptors could potentially serve as new markers for the identification and characterisation of neural stem- and progenitor cells or as targets for manipulation of cellular fate.

  20. Adult stem cel diferentiation and trafficking and their implications in disease.

    PubMed

    Zhuge, Ying; Liu, Zhao-Jun; Velazquez, Omaida C

    2010-01-01

    Stem cells are unspecialized precursor cells that mainly reside in the bone marrow and have important roles in the establishment of embryonic tissue. They also have critical functions during adulthood, where they replenish short-lived mature effector cells and regeneration of injured tissue. They have three main characteristics: self-renewal, differentiation and homeostatic control. In order to maintain a pool of stem cells that support the production of blood cells, stromal elements and connective tissue, stem cells must be able to constantly replenish their own number. They must also possess the ability to differentiate and give rise to a heterogeneous group of functional cells. Finally, stem cells must possess the ability to modulate and balance differentiation and self-renewal according to environmental stimuli and whole-organ needs to prevent the production of excessive number of effector cells.(1) In addition to formation of these cells, regulated movement of stem cells is critical for organogenesis, homeostasis and repair in adulthood. Stem cells require specific inputs from particular environments in order to perform their various functions. Some similar trafficking mechanisms are shared by leukocytes, adult and fetal stem cells, as well as cancer stem cells.(1,2) Achieving proper trafficking of stem cells will allow increased efficiency of targeted cell therapy and drug delivery.(2) In addition, understanding similarities and differences in homing and migration of malignant cancer stem cells will also clarify molecular events of tumor progression and metastasis.(2) This chapter focuses on the differentiation, trafficking and homing of the major types of adult bone marrow stem cells: hematopoietic stem cells (HSCs), mesenchymal stem cells (MSCs) and endothelial progenitor cells (EPCs) and the term"stem cell" will refer to "adult stem cells" unless otherwise specified.

  1. [Phenotypic plasticity of neural crest-derived melanocytes and Schwann cells].

    PubMed

    Dupin, Elisabeth

    2011-01-01

    Melanocytes, the pigmented cells of the skin, and the glial Schwann cells lining peripheral nerves are developmentally derived from an early and transient ectodermal structure of the vertebrate embryo, the neural crest, which is also at the origin of multiple neural and non-neural cell types. Besides melanocytes and neural cells of the peripheral nervous system, the neural crest cells give rise to mesenchymal cell types in the head, which form most of the craniofacial skeleton, dermis, fat tissue and vascular musculo-connective components. How such a wide diversity of differentiation fates is established during embryogenesis and is later maintained in adult tissues are among key questions in developmental and stem cell biology. The analysis of the developmental potentials of single neural crest cells cultured in vitro led to characterizing multipotent stem/progenitor cells as well as more restricted precursors in the early neural crest of avian and mammalian embryos. Data support a hierarchical model of the diversification of neural crest lineages through progressive restrictions of multipotent stem cell potentials driven by local environmental factors. In particular, melanocytes and glial Schwann cells were shown to arise from a common bipotent progenitor, which depends upon the peptide endothelin-3 for proliferation and self-renewal ability. In vivo, signaling by endothelin-3 and its receptor is also required for the early development of melanocytes and proper pigmentation of the vertebrate body. It is generally assumed that, after lineage specification and terminal differentiation, specialized cell types, like the melanocytes and Schwann cells, do not change their identity. However, this classic notion that somatic cell differentiation is a stable and irreversible process has been challenged by emerging evidence that dedifferentiation can occur in different biological systems through nuclear transfer, cell fusion, epigenetic modifications and ectopic gene

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

    SciTech Connect

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

    2014-07-18

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

  3. The role of CD44 in fetal and adult hematopoietic stem cell regulation.

    PubMed

    Cao, Huimin; Heazlewood, Shen Y; Williams, Brenda; Cardozo, Daniela; Nigro, Julie; Oteiza, Ana; Nilsson, Susan K

    2016-01-01

    Throughout development, hematopoietic stem cells migrate to specific microenvironments, where their fate is, in part, extrinsically controlled. CD44 standard as a member of the cell adhesion molecule family is extensively expressed within adult bone marrow and has been previously reported to play important roles in adult hematopoietic regulation via CD44 standard-ligand interactions. In this manuscript, CD44 expression and function are further assessed and characterized on both fetal and adult hematopoietic stem cells. Using a CD44(-/-) mouse model, conserved functional roles of CD44 are revealed throughout development. CD44 is critical in the maintenance of hematopoietic stem and progenitor pools, as well as in hematopoietic stem cell migration. CD44 expression on hematopoietic stem cells as well as other hematopoietic cells within the bone marrow microenvironment is important in the homing and lodgment of adult hematopoietic stem cells isolated from the bone/bone marrow interface. CD44 is also involved in fetal hematopoietic stem cell migration out of the liver, via a process involving stromal cell-derived factor-1α. The absence of CD44 in neonatal bone marrow has no impact on the size of the long-term reconstituting hematopoietic stem cell pool, but results in an enhanced long-term engraftment potential of hematopoietic stem cells.

  4. The role of CD44 in fetal and adult hematopoietic stem cell regulation

    PubMed Central

    Cao, Huimin; Heazlewood, Shen Y.; Williams, Brenda; Cardozo, Daniela; Nigro, Julie; Oteiza, Ana; Nilsson, Susan K.

    2016-01-01

    Throughout development, hematopoietic stem cells migrate to specific microenvironments, where their fate is, in part, extrinsically controlled. CD44 standard as a member of the cell adhesion molecule family is extensively expressed within adult bone marrow and has been previously reported to play important roles in adult hematopoietic regulation via CD44 standard-ligand interactions. In this manuscript, CD44 expression and function are further assessed and characterized on both fetal and adult hematopoietic stem cells. Using a CD44−/− mouse model, conserved functional roles of CD44 are revealed throughout development. CD44 is critical in the maintenance of hematopoietic stem and progenitor pools, as well as in hematopoietic stem cell migration. CD44 expression on hematopoietic stem cells as well as other hematopoietic cells within the bone marrow microenvironment is important in the homing and lodgment of adult hematopoietic stem cells isolated from the bone/bone marrow interface. CD44 is also involved in fetal hematopoietic stem cell migration out of the liver, via a process involving stromal cell-derived factor-1α. The absence of CD44 in neonatal bone marrow has no impact on the size of the long-term reconstituting hematopoietic stem cell pool, but results in an enhanced long-term engraftment potential of hematopoietic stem cells. PMID:26546504

  5. Comparative Study of Efficacy of Epidermal Melanocyte Transfer Versus Hair Follicular Melanocyte Transfer in Stable Vitiligo

    PubMed Central

    Donaparthi, Navya; Chopra, Ajay

    2016-01-01

    Background: Vitiligo surgery has come up a long way from punch skin grafts to epidermal cell suspension and latest to the extracted hair follicle outer root sheath cell suspension (EHFORSCS) transplantation. The progressive development from one technique to the other is always on a quest for the best. In the latest development, EHFORSCS, which is an enriched source of follicular inactive melanocyte (melanocyte stem cells), seems to be a good addition to the prevailing cell-based therapies for vitiligo. However, it needs to be explored further in larger, clinical trials. Methodology: A total of 11 patients with sixty stable vitiligo sites attending dermatology outpatient department were included for the open-labeled, prospective, comparative study. The sites were sequentially distributed into two groups of thirty each. Sites of one group were subjected to epidermal melanocyte transfer (EMT) and the others to hair follicular melanocyte transfer (HFMT). Response to treatment was evaluated on the basis of degree of repigmentation; final evaluation of area of involvement was done after completion of 6 months. Results: At the end of 6 months, repigmentation >90% was observed in 83.33% patches of EMT group and 43.33% in HFMT group. Repigmentation >75% was observed in 90% of patches in Group A and 43.34% of patches in Group B, respectively. There was statistically significant difference in the overall pigmentation between these two groups. Conclusion: Both noncultured autologous epidermal cell suspension transfer and noncultured EHFORSCS transfer are safe and effective surgical modalities in the management of stable vitiligo though EMT has shown a better response in the present study. Outer root sheath cell suspension transfer is a novel, minimally invasive technique in its nascent stage in the surgical management of vitiligo which requires further larger clinical trials for evaluation of its efficacy. PMID:27904182

  6. The Yin and Yang of chromatin dynamics in adult stem cell fate selection

    PubMed Central

    Adam, Rene C.; Fuchs, Elaine

    2015-01-01

    Adult organisms rely on tissue stem cells for maintenance and repair. During homeostasis, the concerted action of local niche signals and epigenetic regulators establish stable gene expression patterns to ensure that stem cells are not lost over time. However, stem cells also provide host tissues with a remarkable plasticity to respond to perturbations. How adult stem cells choose and acquire new fates is unknown, but the genome-wide mapping of epigenetic landscapes suggests a critical role for chromatin remodeling in these processes. Here, we explore the emerging role of chromatin modifiers and pioneer transcription factors in adult stem cell fate decisions and plasticity, which ensure that selective lineage choices are only made when environmentally cued. PMID:26689127

  7. Roles of neural stem cells and adult neurogenesis in adolescent alcohol use disorders.

    PubMed

    Nixon, Kimberly; Morris, Stephanie A; Liput, Daniel J; Kelso, Matthew L

    2010-02-01

    This review discusses the contributions of a newly considered form of plasticity, the ongoing production of new neurons from neural stem cells, or adult neurogenesis, within the context of neuropathologies that occur with excessive alcohol intake in the adolescents. Neural stem cells and adult neurogenesis are now thought to contribute to the structural integrity of the hippocampus, a limbic system region involved in learning, memory, behavioral control, and mood. In adolescents with alcohol use disorders (AUDs), the hippocampus appears to be particularly vulnerable to the neurodegenerative effects of alcohol, but the role of neural stem cells and adult neurogenesis in alcoholic neuropathology has only recently been considered. This review encompasses a brief overview of neural stem cells and the processes involved in adult neurogenesis, how neural stem cells are affected by alcohol, and possible differences in the neurogenic niche between adults and adolescents. Specifically, what is known about developmental differences in adult neurogenesis between the adult and adolescent is gleaned from the literature, as well as how alcohol affects this process differently among the age groups. Finally, this review suggests differences that may exist in the neurogenic niche between adults and adolescents and how these differences may contribute to the susceptibility of the adolescent hippocampus to damage. However, many more studies are needed to discern whether these developmental differences contribute to the vulnerability of the adolescent to developing an AUD.

  8. Adult stem cells in neural repair: Current options, limitations and perspectives.

    PubMed

    Mariano, Eric Domingos; Teixeira, Manoel Jacobsen; Marie, Suely Kazue Nagahashi; Lepski, Guilherme

    2015-03-26

    Stem cells represent a promising step for the future of regenerative medicine. As they are able to differentiate into any cell type, tissue or organ, these cells are great candidates for treatments against the worst diseases that defy doctors and researchers around the world. Stem cells can be divided into three main groups: (1) embryonic stem cells; (2) fetal stem cells; and (3) adult stem cells. In terms of their capacity for proliferation, stem cells are also classified as totipotent, pluripotent or multipotent. Adult stem cells, also known as somatic cells, are found in various regions of the adult organism, such as bone marrow, skin, eyes, viscera and brain. They can differentiate into unipotent cells of the residing tissue, generally for the purpose of repair. These cells represent an excellent choice in regenerative medicine, every patient can be a donor of adult stem cells to provide a more customized and efficient therapy against various diseases, in other words, they allow the opportunity of autologous transplantation. But in order to start clinical trials and achieve great results, we need to understand how these cells interact with the host tissue, how they can manipulate or be manipulated by the microenvironment where they will be transplanted and for how long they can maintain their multipotent state to provide a full regeneration.

  9. Repair of tissues by adult stem/progenitor cells (MSCs): controversies, myths, and changing paradigms.

    PubMed

    Prockop, Darwin J

    2009-06-01

    Research on stem cells has progressed at a rapid pace and, as might be anticipated, the results have generated several controversies, a few myths and a change in a major paradigm. Some of these issues will be reviewed in this study with special emphasis on how they can be applied to the adult stem/progenitor cells from bone marrow, referred to as MSCs.

  10. Epistatic adult plant resistance in wheat to stem rust cosegregates with Sr12 seedling resistance

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Wheat adult plant resistance (APR) to stem rust is desirable. Researchers have characterized the inheritance of APR in cultivar Thatcher as complex. In order to identify the loci providing APR in Thatcher, we evaluated 160 RILs derived from Thatcher/McNeal for stem rust reaction in the field in Keny...

  11. Lin-28 promotes symmetric stem cell division and drives adaptive growth in the adult Drosophila intestine.

    PubMed

    Chen, Ching-Huan; Luhur, Arthur; Sokol, Nicholas

    2015-10-15

    Stem cells switch between asymmetric and symmetric division to expand in number as tissues grow during development and in response to environmental changes. The stem cell intrinsic proteins controlling this switch are largely unknown, but one candidate is the Lin-28 pluripotency factor. A conserved RNA-binding protein that is downregulated in most animals as they develop from embryos to adults, Lin-28 persists in populations of adult stem cells. Its function in these cells has not been previously characterized. Here, we report that Lin-28 is highly enriched in adult intestinal stem cells in the Drosophila intestine. lin-28 null mutants are homozygous viable but display defects in this population of cells, which fail to undergo a characteristic food-triggered expansion in number and have reduced rates of symmetric division as well as reduced insulin signaling. Immunoprecipitation of Lin-28-bound mRNAs identified Insulin-like Receptor (InR), forced expression of which completely rescues lin-28-associated defects in intestinal stem cell number and division pattern. Furthermore, this stem cell activity of lin-28 is independent of one well-known lin-28 target, the microRNA let-7, which has limited expression in the intestinal epithelium. These results identify Lin-28 as a stem cell intrinsic factor that boosts insulin signaling in intestinal progenitor cells and promotes their symmetric division in response to nutrients, defining a mechanism through which Lin-28 controls the adult stem cell division patterns that underlie tissue homeostasis and regeneration.

  12. New melanogenesis and photobiological processes in activation and proliferation of precursor melanocytes after UV-exposure: ultrastructural differentiation of precursor melanocytes from Langerhans cells

    SciTech Connect

    Jimbow, K.; Uesugi, T.

    1982-02-01

    Photobiological processes involving new melanogenesis after exposure to ultraviolet (UV) light were experimentally studied in C57 black adult mice by histochemistry, cytochemistry, and autoradiography. The trunk and the plantar region of the foot, where no functioning melanocytes were present before exposure, were exposed to UV-A for 14 consecutive days. Both regions revealed a basically similar pattern for new melanogenesis which involved an activation of precursor melanocytes. Essentially all of ''indeterminate'' cells appeared to be precursor melanocytes, the fine structure of which could be differentiated even from poorly developed Langerhans cells. New melanogenesis was manifested by 4 stages of cellular and subcellular reactions of these cells as indicated by histochemistry of dihydroxyphenylalanine (dopa) and autoradiography of thymidine incorporation: (a) an initial lag in the activation of precursor melanocytes with development of Golgi cisternae and rough endoplasmic reticulum followed by formation of unmelanized melanosomes (day 0 to 2); (b) synthesis of active tyrosinase accumulated in Golgi cisternae and vesicles with subsequent formation of melanized melanosomes in these cells (day 3 to 5); (c) mitotic proliferation of many of these activated cells, followed by an exponential increase of new melanocytes (day 6 to 7); and (d) melanosome transfer with differentiation of 10 nm filaments and arborization of dendrites, but without any significant change in the melanocyte population (day 8 to 14). The melanosome transfer was, however, not obvious until after 7 days of exposure. The size of newly synthesized melanosomes was similar to that of tail skin where native melanocytes were present before exposure.

  13. Enhanced ex vivo expansion of adult mesenchymal stem cells by fetal mesenchymal stem cell ECM.

    PubMed

    Ng, Chee Ping; Sharif, Abdul Rahim Mohamed; Heath, Daniel E; Chow, John W; Zhang, Claire B Y; Chan-Park, Mary B; Hammond, Paula T; Chan, Jerry K Y; Griffith, Linda G

    2014-04-01

    Large-scale expansion of highly functional adult human mesenchymal stem cells (aMSCs) remains technologically challenging as aMSCs lose self renewal capacity and multipotency during traditional long-term culture and their quality/quantity declines with donor age and disease. Identification of culture conditions enabling prolonged expansion and rejuvenation would have dramatic impact in regenerative medicine. aMSC-derived decellularized extracellular matrix (ECM) has been shown to provide such microenvironment which promotes MSC self renewal and "stemness". Since previous studies have demonstrated superior proliferation and osteogenic potential of human fetal MSCs (fMSCs), we hypothesize that their ECM may promote expansion of clinically relevant aMSCs. We demonstrated that aMSCs were more proliferative (∼ 1.6 ×) on fMSC-derived ECM than aMSC-derived ECMs and traditional tissue culture wares (TCPS). These aMSCs were smaller and more uniform in size (median ± interquartile range: 15.5 ± 4.1 μm versus 17.2 ± 5.0 μm and 15.5 ± 4.1 μm for aMSC ECM and TCPS respectively), exhibited the necessary biomarker signatures, and stained positive for osteogenic, adipogenic and chondrogenic expressions; indications that they maintained multipotency during culture. Furthermore, fMSC ECM improved the proliferation (∼ 2.2 ×), size (19.6 ± 11.9 μm vs 30.2 ± 14.5 μm) and differentiation potential in late-passaged aMSCs compared to TCPS. In conclusion, we have established fMSC ECM as a promising cell culture platform for ex vivo expansion of aMSCs.

  14. Genetics Home Reference: giant congenital melanocytic nevus

    MedlinePlus

    ... noncancerous skin patch (nevus) that is composed of pigment-producing cells called melanocytes . It is present from ... called neurocutaneous melanosis, which is the presence of pigment-producing skin cells (melanocytes) in the tissue that ...

  15. Adult bone marrow-derived stem cells for organ regeneration and repair.

    PubMed

    Tögel, Florian; Westenfelder, Christof

    2007-12-01

    Stem cells have been recognized as a potential tool for the development of innovative therapeutic strategies. There are in general two types of stem cells, embryonic and adult stem cells. While embryonic stem cell therapy has been riddled with problems of allogeneic rejection and ethical concerns, adult stem cells have long been used in the treatment of hematological malignancies. With the recognition of additional, potentially therapeutic characteristics, bone marrow-derived stem cells have become a tool in regenerative medicine. The bone marrow is an ideal source of stem cells because it is easily accessible and harbors two types of stem cells. Hematopoietic stem cells give rise to all blood cell types and have been shown to exhibit plasticity, while multipotent marrow stromal cells are the source of osteocytes, chondrocytes, and fat cells and have been shown to support and generate a large number of different cell types. This review describes the general characteristics of these stem cell populations and their current and potential future applications in regenerative medicine.

  16. Isolation, cultivation, and characterization of adult murine prostate stem cells

    PubMed Central

    Lukacs, Rita U.; Goldstein, Andrew S.; Lawson, Devon A.; Cheng, Donghui; Witte, Owen N.

    2010-01-01

    ABSTRACT/SUMMARY The successful isolation and cultivation of prostate stem cells will allow us to study their unique biological properties and their application in therapeutic approaches. Here we provide step-by-step procedures on the basis of previous work in our laboratory for: the harvesting of primary prostate cells from adolescent male mice by a modified enzymatic procedure; the isolation of an enriched population of prostate stem cells through cell sorting; the cultivation of prostate stem cells in vitro; and characterization of these cells and their stem-like activity, including in vivo tubule regeneration. Normally it will take approximately 8 hours to harvest prostate cells, isolate the stem cell enriched population, and set up the in vitro sphere assay. It will take up to 8 weeks to analyze the unique properties of the stem cells, including their regenerative capacity in vivo. PMID:20360765

  17. Isolation, cultivation and characterization of adult murine prostate stem cells.

    PubMed

    Lukacs, Rita U; Goldstein, Andrew S; Lawson, Devon A; Cheng, Donghui; Witte, Owen N

    2010-04-01

    The successful isolation and cultivation of prostate stem cells will allow us to study their unique biological properties and their application in therapeutic approaches. Here we describe step-by-step procedures on the basis of previous work in our laboratory for the harvesting of primary prostate cells from adolescent male mice by a modified enzymatic procedure; the isolation of an enriched population of prostate stem cells through cell sorting; and the cultivation of prostate stem cells in vitro and characterization of these cells and their stem-like activity, including in vivo tubule regeneration. Normally, it will take approximately 8 h to harvest prostate cells, isolate the stem cell-enriched population and set up the in vitro sphere assay. It will take up to 8 weeks to analyze the unique properties of the stem cells, including their regenerative capacity in vivo.

  18. Immune physiology and oogenesis in fetal and adult humans, ovarian infertility, and totipotency of adult ovarian stem cells.

    PubMed

    Bukovsky, Antonin; Caudle, Michael R; Virant-Klun, Irma; Gupta, Satish K; Dominguez, Roberto; Svetlikova, Marta; Xu, Fei

    2009-03-01

    It is still widely believed that while oocytes in invertebrates and lower vertebrates are periodically renewed throughout life, oocytes in humans and higher vertebrates are formed only during the fetal/perinatal period. However, this dogma is questioned, and clashes with Darwinian evolutionary theory. Studies of oogenesis and follicular renewal from ovarian stem cells (OSCs) in adult human ovaries, and of the role of third-party bone marrow-derived cells (monocyte-derived tissue macrophages and T lymphocytes) could help provide a better understanding of the causes of ovarian infertility, its prevention, and potential treatment. We have reported differentiation of distinct cell types from OSC and the production of new eggs in cultures derived from premenopausal and postmenopausal human ovaries. OSCs are also capable of producing neural/neuronal cells in vitro after sequential stimulation with sex steroid combinations. Hence, OSC represent a unique type of totipotent adult stem cells, which could be utilized for autologous treatment of premature ovarian failure and also for autologous stem cell therapy of neurodegenerative diseases without use of allogeneic embryonic stem cells or somatic cell nuclear transfer. The in vivo application of sex steroid combinations may augment the proliferation of existing neural stem cells and their differentiation into mature neuronal cells (systemic regenerative therapy). Such treatment may also stimulate the transdifferentiation of autologous neural stem cell precursors into neural stem cells useful for topical or systemic regenerative treatment.

  19. Somatic stem cells express Piwi and Vasa genes in an adult ctenophore: ancient association of "germline genes" with stemness.

    PubMed

    Alié, Alexandre; Leclère, Lucas; Jager, Muriel; Dayraud, Cyrielle; Chang, Patrick; Le Guyader, Hervé; Quéinnec, Eric; Manuel, Michaël

    2011-02-01

    Stem cells are essential for animal development and adult tissue homeostasis, and the quest for an ancestral gene fingerprint of stemness is a major challenge for evolutionary developmental biology. Recent studies have indicated that a series of genes, including the transposon silencer Piwi and the translational activator Vasa, specifically involved in germline determination and maintenance in classical bilaterian models (e.g., vertebrates, fly, nematode), are more generally expressed in adult multipotent stem cells in other animals like flatworms and hydras. Since the progeny of these multipotent stem cells includes both somatic and germinal derivatives, it remains unclear whether Vasa, Piwi, and associated genes like Bruno and PL10 were ancestrally linked to stemness, or to germinal potential. We have investigated the expression of Vasa, two Piwi paralogues, Bruno and PL10 in Pleurobrachia pileus, a member of the early-diverging phylum Ctenophora, the probable sister group of cnidarians. These genes were all expressed in the male and female germlines, and with the exception of one of the Piwi paralogues, they showed similar expression patterns within somatic territories (tentacle root, comb rows, aboral sensory complex). Cytological observations and EdU DNA-labelling and long-term retention experiments revealed concentrations of stem cells closely matching these gene expression areas. These stem cell pools are spatially restricted, and each specialised in the production of particular types of somatic cells. These data unveil important aspects of cell renewal within the ctenophore body and suggest that Piwi, Vasa, Bruno, and PL10 belong to a gene network ancestrally acting in two distinct contexts: (i) the germline and (ii) stem cells, whatever the nature of their progeny.

  20. RNA-Seq Reveals the Angiogenesis Diversity between the Fetal and Adults Bone Mesenchyme Stem Cell.

    PubMed

    Zhao, Xin; Han, Yingmin; Liang, Yu; Nie, Chao; Wang, Jian

    2016-01-01

    In this research, we used RNA sequencing (RNA-seq) to analyze 23 single cell samples and 2 bulk cells sample from human adult bone mesenchyme stem cell line and human fetal bone mesenchyme stem cell line. The results from the research demonstrated that there were big differences between two cell lines. Adult bone mesenchyme stem cell lines showed a strong trend on the blood vessel differentiation and cell motion, 48/49 vascular related differential expressed genes showed higher expression in adult bone mesenchyme stem cell lines (Abmsc) than fetal bone mesenchyme stem cell lines (Fbmsc). 96/106 cell motion related genes showed the same tendency. Further analysis showed that genes like ANGPT1, VEGFA, FGF2, PDGFB and PDGFRA showed higher expression in Abmsc. This work showed cell heterogeneity between human adult bone mesenchyme stem cell line and human fetal bone mesenchyme stem cell line. Also the work may give an indication that Abmsc had a better potency than Fbmsc in the future vascular related application.

  1. CRIPTO/GRP78 Signaling Maintains Fetal and Adult Mammary Stem Cells Ex Vivo

    PubMed Central

    Spike, Benjamin T.; Kelber, Jonathan A.; Booker, Evan; Kalathur, Madhuri; Rodewald, Rose; Lipianskaya, Julia; La, Justin; He, Marielle; Wright, Tracy; Klemke, Richard; Wahl, Geoffrey M.; Gray, Peter C.

    2014-01-01

    Summary Little is known about the extracellular signaling factors that govern mammary stem cell behavior. Here, we identify CRIPTO and its cell-surface receptor GRP78 as regulators of stem cell behavior in isolated fetal and adult mammary epithelial cells. We develop a CRIPTO antagonist that promotes differentiation and reduces self-renewal of mammary stem cell-enriched populations cultured ex vivo. By contrast, CRIPTO treatment maintains the stem cell phenotype in these cultures and yields colonies with enhanced mammary gland reconstitution capacity. Surface expression of GRP78 marks CRIPTO-responsive, stem cell-enriched fetal and adult mammary epithelial cells, and deletion of GRP78 from adult mammary epithelial cells blocks their mammary gland reconstitution potential. Together, these findings identify the CRIPTO/GRP78 pathway as a developmentally conserved regulator of fetal and adult mammary stem cell behavior ex vivo, with implications for the stem-like cells found in many cancers. PMID:24749068

  2. Adipose-derived adult stem cells: available technologies for potential clinical regenerative applications in dentistry.

    PubMed

    Catalano, Enrico; Cochis, Andrea; Varoni, Elena; Rimondini, Lia; Carrassi, Antonio; Azzimonti, Barbara

    2013-01-01

    Tissue homeostasis depends closely on the activity and welfare of adult stem cells. These cells represent a promising tool for biomedical research since they can aid in treatment and promote the regeneration of damaged organs in many human disorders. Adult stem cells indefinitely preserve their ability to self-renew and differentiate into various phenotypes; this capacity could be promoted in vitro by particular culture conditions (differentiation media) or spontaneously induced in vivo by exploiting the biochemical and mechanical properties of the tissue in which the stem cells are implanted. Among the different sources of adult stem cells, adipose tissue is an attractive possibility thanks to its ready availability and the standard extraction techniques at our disposal today. This review discusses the isolation, characterization, and differentiation of human adipose-derived adult stem cells, as well as regeneration strategies, therapeutic uses, and adverse effects of their delivery. In particular, since oral disorders (e.g., trauma, erosion, and chronic periodontitis) often cause the loss of dental tissue along with functional, phonetic, and aesthetic impairment, this review focuses on the application of human adipose-derived adult stem cells, alone or in combination with biomaterials, in treating oral diseases.

  3. Does the adult human ciliary body epithelium contain "true" retinal stem cells?

    PubMed

    Frøen, Rebecca; Johnsen, Erik O; Nicolaissen, Bjørn; Facskó, Andrea; Petrovski, Goran; Moe, Morten C

    2013-01-01

    Recent reports of retinal stem cells being present in several locations of the adult eye have sparked great hopes that they may be used to treat the millions of people worldwide who suffer from blindness as a result of retinal disease or injury. A population of proliferative cells derived from the ciliary body epithelium (CE) has been considered one of the prime stem cell candidates, and as such they have received much attention in recent years. However, the true nature of these cells in the adult human eye has still not been fully elucidated, and the stem cell claim has become increasingly controversial in light of new and conflicting reports. In this paper, we will try to answer the question of whether the available evidence is strong enough for the research community to conclude that the adult human CE indeed harbors stem cells.

  4. Stem Cells

    MedlinePlus

    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 ...

  5. NF1 loss induces senescence during human melanocyte differentiation in an iPSC-based model.

    PubMed

    Larribere, Lionel; Wu, Huizi; Novak, Daniel; Galach, Marta; Bernhardt, Mathias; Orouji, Elias; Weina, Kasia; Knappe, Nathalie; Sachpekidis, Christos; Umansky, Ludmila; Beckhove, Philipp; Umansky, Viktor; De Schepper, Sofie; Kaufmann, Dieter; Ballotti, Robert; Bertolotto, Corine; Utikal, Jochen

    2015-07-01

    Neurofibromatosis type 1 (NF1) is a frequent genetic disease leading to the development of Schwann cell-derived neurofibromas or melanocytic lesions called café-au-lait macules (CALMs). The molecular mechanisms involved in CALMs formation remain largely unknown. In this report, we show for the first time pathophysiological mechanisms of abnormal melanocyte differentiation in a human NF1(+/-) -induced pluripotent stem cell (iPSC)-based model. We demonstrate that NF1 patient-derived fibroblasts can be successfully reprogrammed in NF1(+/-) iPSCs with active RAS signaling and that NF1 loss induces senescence during melanocyte differentiation as well as in patient's-derived CALMs, revealing a new role for NF1 in the melanocyte lineage.

  6. ADULT NEURAL STEM CELLS: RESPONSE TO STROKE INJURY AND POTENTIAL FOR THERAPEUTIC APPLICATIONS

    PubMed Central

    Barkho, Basam Z.; Zhao, Xinyu

    2011-01-01

    The plasticity of neural stem/progenitor cells allows a variety of different responses to many environmental cues. In the past decade, significant research has gone into understanding the regulation of neural stem/progenitor cell properties, because of their promise for cell replacement therapies in adult neurological diseases. Both endogenous and grafted neural stem/progenitor cells are known to have the ability to migrate long distances to lesioned sites after brain injury and differentiate into new neurons. Several chemokines and growth factors, including stromal cell-derived factor-1 and vascular endothelial growth factor, have been shown to stimulate the proliferation, differentiation, and migration of neural stem/progenitor cells, and investigators have now begun to identify the critical downstream effectors and signaling mechanisms that regulate these processes. Both our own lab and others have shown that the extracellular matrix and matrix remodeling factors play a critical role in directing cell differentiation and migration of adult neural stem/progenitor cells within injured sites. Identification of these and other molecular pathways involved in stem cell homing into ischemic areas is vital for the development of new treatments. To ensure the best functional recovery, regenerative therapy may require the application of a combination approach that includes cell replacement, trophic support, and neural protection. Here we review the current state of our knowledge about endogenous adult and exogenous neural stem/progenitor cells as potential therapeutic agents for central nervous system injuries. PMID:21466483

  7. Great promise of tissue-resident adult stem/progenitor cells in transplantation and cancer therapies.

    PubMed

    Mimeault, Murielle; Batra, Surinder K

    2012-01-01

    Recent progress in tissue-resident adult stem/progenitor cell research has inspired great interest because these immature cells from your own body can act as potential, easily accessible cell sources for cell transplantation in regenerative medicine and cancer therapies. The use of adult stem/progenitor cells endowed with a high self-renewal ability and multilineage differentiation potential, which are able to regenerate all the mature cells in the tissues from their origin, offers great promise in replacing non-functioning or lost cells and regenerating diseased and damaged tissues. The presence of a small subpopulation of adult stem/progenitor cells in most tissues and organs provides the possibility of stimulating their in vivo differentiation, or of using their ex vivo expanded progenies for cell-replacement and gene therapies with multiple applications in humans without a high-risk of graft rejection and major side effects. Among the diseases that could be treated by adult stem cell-based therapies are hematopoietic and immune disorders, multiple degenerative disorders such as Parkinson's and Alzheimer's diseases, Types 1 and 2 diabetes mellitus as well as skin, eye, liver, lung, tooth and cardiovascular disorders. In addition, a combination of the current cancer treatments with an adjuvant treatment consisting of an autologous or allogeneic adult stem/progenitor cell transplantation also represents a promising strategy for treating and even curing diverse aggressive, metastatic, recurrent and lethal cancers. In this chapter, we reviewed the most recent advancements on the characterization of phenotypic and functional properties of adult stem/progenitor cell types found in bone marrow, heart, brain and other tissues and discussed their therapeutic implications in the stem cell-based transplantation therapy.

  8. Wildtype adult stem cells, unlike tumor cells, are resistant to cellular damages in Drosophila.

    PubMed

    Ma, Meifang; Zhao, Hang; Zhao, Hanfei; Binari, Richard; Perrimon, Norbert; Li, Zhouhua

    2016-03-15

    Adult stem cells or residential progenitor cells are critical to maintain the structure and function of adult tissues (homeostasis) throughout the lifetime of an individual. Mis-regulation of stem cell proliferation and differentiation often leads to diseases including cancer, however, how wildtype adult stem cells and cancer cells respond to cellular damages remains unclear. We find that in the adult Drosophila midgut, intestinal stem cells (ISCs), unlike tumor intestinal cells, are resistant to various cellular damages. Tumor intestinal cells, unlike wildtype ISCs, are easily eliminated by apoptosis. Further, their proliferation is inhibited upon autophagy induction, and autophagy-mediated tumor inhibition is independent of caspase-dependent apoptosis. Interestingly, inhibition of tumorigenesis by autophagy is likely through the sequestration and degradation of mitochondria, as compromising mitochondria activity in these tumor models mimics the induction of autophagy and increasing the production of mitochondria alleviates the tumor-suppression capacity of autophagy. Together, these data demonstrate that wildtype adult stem cells and tumor cells show dramatic differences in sensitivity to cellular damages, thus providing potential therapeutic implications targeting tumorigenesis.

  9. Neuroendocrine activity of the melanocyte

    PubMed Central

    Slominski, Andrzej

    2009-01-01

    More than 15 years ago, we have proposed that melanocytes are sensory and regulatory cells with computing capability, which transform external and/or internal signals/energy into organized regulatory network(s) for the maintenance of the cutaneous homeostasis. This concept is substantiated by accumulating evidence that melanocytes produce classical stress neurotransmitters, neuropeptides and hormones, express corresponding receptors and these processes are modified and/or regulated by ultraviolet radiation, biological factors or stress. Examples of the above are catecholamines, serotonin, N-acetyl-serotonin, melatonin, proopiomelanocortin-derived adrenocorticotropic hormone, β-endorphin or melanocyte-stimulating hormone peptides, corticotropin releasing factor, related urocortins and corticosteroids including cortisol and corticosterone as well as their precursors. Furthermore, their production is not random, but hierarchical and follows the structures of classical neuroendocrine organizations such as hypothalamic-pituitary-adrenal axis, serotoninergic, melatoninergic and catecholaminergic systems. An example of an intrinsic but overlooked neuroendocrine activity is production and secretion of melanogenesis intermediates including L-DOPA or its derivatives that could enter circulation and act on distant sites. Such capabilities have defined melanocytes as neuroendocrine cells that not only coordinate cutaneous but also can affect a global homeostasis. PMID:19558501

  10. Human oocytes reprogram adult somatic nuclei of a type 1 diabetic to diploid pluripotent stem cells.

    PubMed

    Yamada, Mitsutoshi; Johannesson, Bjarki; Sagi, Ido; Burnett, Lisa Cole; Kort, Daniel H; Prosser, Robert W; Paull, Daniel; Nestor, Michael W; Freeby, Matthew; Greenberg, Ellen; Goland, Robin S; Leibel, Rudolph L; Solomon, Susan L; Benvenisty, Nissim; Sauer, Mark V; Egli, Dieter

    2014-06-26

    The transfer of somatic cell nuclei into oocytes can give rise to pluripotent stem cells that are consistently equivalent to embryonic stem cells, holding promise for autologous cell replacement therapy. Although methods to induce pluripotent stem cells from somatic cells by transcription factors are widely used in basic research, numerous differences between induced pluripotent stem cells and embryonic stem cells have been reported, potentially affecting their clinical use. Because of the therapeutic potential of diploid embryonic stem-cell lines derived from adult cells of diseased human subjects, we have systematically investigated the parameters affecting efficiency of blastocyst development and stem-cell derivation. Here we show that improvements to the oocyte activation protocol, including the use of both kinase and translation inhibitors, and cell culture in the presence of histone deacetylase inhibitors, promote development to the blastocyst stage. Developmental efficiency varied between oocyte donors, and was inversely related to the number of days of hormonal stimulation required for oocyte maturation, whereas the daily dose of gonadotropin or the total number of metaphase II oocytes retrieved did not affect developmental outcome. Because the use of concentrated Sendai virus for cell fusion induced an increase in intracellular calcium concentration, causing premature oocyte activation, we used diluted Sendai virus in calcium-free medium. Using this modified nuclear transfer protocol, we derived diploid pluripotent stem-cell lines from somatic cells of a newborn and, for the first time, an adult, a female with type 1 diabetes.

  11. A planarian p53 homolog regulates proliferation and self-renewal in adult stem cell lineages.

    PubMed

    Pearson, Bret J; Sánchez Alvarado, Alejandro

    2010-01-01

    The functions of adult stem cells and tumor suppressor genes are known to intersect. However, when and how tumor suppressors function in the lineages produced by adult stem cells is unknown. With a large population of stem cells that can be manipulated and studied in vivo, the freshwater planarian is an ideal system with which to investigate these questions. Here, we focus on the tumor suppressor p53, homologs of which have no known role in stem cell biology in any invertebrate examined thus far. Planaria have a single p53 family member, Smed-p53, which is predominantly expressed in newly made stem cell progeny. When Smed-p53 is targeted by RNAi, the stem cell population increases at the expense of progeny, resulting in hyper-proliferation. However, ultimately the stem cell population fails to self-renew. Our results suggest that prior to the vertebrates, an ancestral p53-like molecule already had functions in stem cell proliferation control and self-renewal.

  12. Melanocytes Affect Nodal Expression and Signaling in Melanoma Cells: A Lesson from Pediatric Large Congenital Melanocytic Nevi.

    PubMed

    Margaryan, Naira V; Gilgur, Alina; Seftor, Elisabeth A; Purnell, Chad; Arva, Nicoleta C; Gosain, Arun K; Hendrix, Mary J C; Strizzi, Luigi

    2016-03-22

    Expression of Nodal, a Transforming Growth Factor-beta (TGF-β) related growth factor, is associated with aggressive melanoma. Nodal expression in adult dysplastic nevi may predict the development of aggressive melanoma in some patients. A subset of pediatric patients diagnosed with giant or large congenital melanocytic nevi (LCMN) has shown increased risk for development of melanoma. Here, we investigate whether Nodal expression can help identify the rare cases of LCMN that develop melanoma and shed light on why the majority of these patients do not. Immunohistochemistry (IHC) staining results show varying degree of Nodal expression in pediatric dysplastic nevi and LCMN. Moreover, median scores from Nodal IHC expression analysis were not significantly different between these two groups. Additionally, none of the LCMN patients in this study developed melanoma, regardless of Nodal IHC levels. Co-culture experiments revealed reduced tumor growth and lower levels of Nodal and its signaling molecules P-SMAD2 and P-ERK1/2 when melanoma cells were grown in vivo or in vitro with normal melanocytes. The same was observed in melanoma cells cultured with melanocyte conditioned media containing pigmented melanocyte derived melanosomes (MDM). Since MDM contain molecules capable of inactivating radical oxygen species, to investigate potential anti-oxidant effect of MDM on Nodal expression and signaling in melanoma, melanoma cells were treated with either N-acetyl-l-cysteine (NAC), a component of the anti-oxidant glutathione or synthetic melanin, which in addition to providing pigmentation can also exert free radical scavenging activity. Melanoma cells treated with NAC or synthetic melanin showed reduced levels of Nodal, P-SMAD2 and P-ERK1/2 compared to untreated melanoma cells. Thus, the potential role for Nodal in melanoma development in LCMN is less evident than in adult dysplastic nevi possibly due to melanocyte cross-talk in LCMN capable of offsetting or delaying the pro

  13. Diversity of Epithelial Stem Cell Types in Adult Lung

    PubMed Central

    Li, Feng; He, Jinxi; Wei, Jun; Cho, William C.; Liu, Xiaoming

    2015-01-01

    Lung is a complex organ lined with epithelial cells. In order to maintain its homeostasis and normal functions following injuries caused by varied extraneous and intraneous insults, such as inhaled environmental pollutants and overwhelming inflammatory responses, the respiratory epithelium normally undergoes regenerations by the proliferation and differentiation of region-specific epithelial stem/progenitor cells that resided in distinct niches along the airway tree. The importance of local epithelial stem cell niches in the specification of lung stem/progenitor cells has been recently identified. Studies using cell differentiating and lineage tracing assays, in vitro and/or ex vivo models, and genetically engineered mice have suggested that these local epithelial stem/progenitor cells within spatially distinct regions along the pulmonary tree contribute to the injury repair of epithelium adjacent to their respective niches. This paper reviews recent findings in the identification and isolation of region-specific epithelial stem/progenitor cells and local niches along the airway tree and the potential link of epithelial stem cells for the development of lung cancer. PMID:25810726

  14. Fetal and adult liver stem cells for liver regeneration and tissue engineering.

    PubMed

    Fiegel, H C; Lange, Claudia; Kneser, U; Lambrecht, W; Zander, A R; Rogiers, X; Kluth, D

    2006-01-01

    For the development of innovative cell-based liver directed therapies, e.g. liver tissue engineering, the use of stem cells might be very attractive to overcome the limitation of donor liver tissue. Liver specific differentiation of embryonic, fetal or adult stem cells is currently under investigation. Different types of fetal liver (stem) cells during development were identified, and their advantageous growth potential and bipotential differentiation capacity were shown. However, ethical and legal issues have to be addressed before using fetal cells. Use of adult stem cells is clinically established, e.g. transplantation of hematopoietic stem cells. Other bone marrow derived liver stem cells might be mesenchymal stem cells (MSC). However, the transdifferentiation potential is still in question due to the observation of cellular fusion in several in vivo experiments. In vitro experiments revealed a crucial role of the environment (e.g. growth factors and extracellular matrix) for specific differentiation of stem cells. Co-cultured liver cells also seemed to be important for hepatic gene expression of MSC. For successful liver cell transplantation, a novel approach of tissue engineering by orthotopic transplantation of gel-immobilized cells could be promising, providing optimal environment for the injected cells. Moreover, an orthotopic tissue engineering approach using bipotential stem cells could lead to a repopulation of the recipients liver with healthy liver and biliary cells, thus providing both hepatic functions and biliary excretion. Future studies have to investigate, which stem cell and environmental conditions would be most suitable for the use of stem cells for liver regeneration or tissue engineering approaches.

  15. Typography manipulations can affect priming of word stem completion in older and younger adults.

    PubMed

    Gibson, J M; Brooks, J O; Friedman, L; Yesavage, J A

    1993-12-01

    The experiments reported here investigated whether changes of typography affected priming of word stem completion performance in older and younger adults. Across all experiments, the typeface in which a word appeared at presentation either did or did not match that of its 3-letter stem at test. In Experiment 1, no significant evidence of a typography effect was found when words were presented with a sentence judgment or letter judgment task. However, subsequent experiments revealed that, in both older and younger adults, only words presented with a syllable judgment task gave rise to the typography effect (Experiments 2-4). Specifically, performance was greater, when the presentation and test typeface matched than when they did not. Experiment 5, which used stem-cued recall, did not reveal a difference between syllable and letter judgment tasks. These findings highlight the complex nature of word stem completion performance.

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

    PubMed Central

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

    2015-01-01

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

  17. An essential and evolutionarily conserved role of protein arginine methyltransferase 1 for adult intestinal stem cells during postembryonic development.

    PubMed

    Matsuda, Hiroki; Shi, Yun-Bo

    2010-11-01

    Organ-specific adult stem cells are critical for the homeostasis of adult organs and organ repair and regeneration. Unfortunately, it has been difficult to investigate the origins of these stem cells and the mechanisms of their development, especially in mammals. Intestinal remodeling during frog metamorphosis offers a unique opportunity for such studies. During the transition from an herbivorous tadpole to a carnivorous frog, the intestine is completely remodeled as the larval epithelial cells undergo apoptotic degeneration and are replaced by adult epithelial cells developed de novo. The entire metamorphic process is under the control of thyroid hormone, making it possible to control the development of the adult intestinal stem cells. Here, we show that the thyroid hormone receptor-coactivator protein arginine methyltransferase 1 (PRMT1) is upregulated in a small number of larval epithelial cells and that these cells dedifferentiate to become the adult stem cells. More importantly, transgenic overexpression of PRMT1 leads to increased adult stem cells in the intestine, and conversely, knocking down the expression of endogenous PRMT1 reduces the adult stem cell population. In addition, PRMT1 expression pattern during zebrafish and mouse development suggests that PRMT1 may play an evolutionally conserved role in the development of adult intestinal stem cells throughout vertebrates. These findings are not only important for the understanding of organ-specific adult stem cell development but also have important implications in regenerative medicine of the digestive tract.

  18. Chemokine-mobilized adult stem cells; defining a better hematopoietic graft.

    PubMed

    Pelus, L M; Fukuda, S

    2008-03-01

    Stem cell research is currently focused on totipotent stem cells and their therapeutic potential, however adult stem cells, while restricted to differentiation within their tissue or origin, also have therapeutic utility. Transplantation with bone marrow hematopoietic stem cells (HSC) has been used for curative therapy for decades. More recently, alternative sources of HSC, particularly those induced to exit marrow or mobilize to peripheral blood by G-CSF, have become the most widely used hematopoietic graft and show significant superiority to marrow HSC. The chemokine/chemokine receptor axis also mobilizes HSC that occurs more rapidly than with G-CSF. In mice, the HSC and progenitor cells (HPC) mobilized by the CXCR2 receptor agonist GRObeta can be harvested within minutes of administration and show significantly lower levels of apoptosis, enhanced homing to marrow, expression of more activated integrin receptors and superior repopulation kinetics and more competitive engraftment than the equivalent cells mobilized by G-CSF. These characteristics suggest that chemokine axis-mobilized HSC represent a population of adult stem cells distinct from those mobilized by G-CSF, with superior therapeutic potential. It remains to be determined if the chemokine mobilization axis can be harnessed to mobilize other populations of unique adult stem cells with clinical utility.

  19. Concise Review: Quiescence in Adult Stem Cells: Biological Significance and Relevance to Tissue Regeneration.

    PubMed

    Rumman, Mohammad; Dhawan, Jyotsna; Kassem, Moustapha

    2015-10-01

    Adult stem cells (ASCs) are tissue resident stem cells responsible for tissue homeostasis and regeneration following injury. In uninjured tissues, ASCs exist in a nonproliferating, reversibly cell cycle-arrested state known as quiescence or G0. A key function of the quiescent state is to preserve stemness in ASCs by preventing precocious differentiation, and thus maintaining a pool of undifferentiated ASCs. Recent evidences suggest that quiescence is an actively maintained state and that excessive or defective quiescence may lead to compromised tissue regeneration or tumorigenesis. The aim of this review is to provide an update regarding the biological mechanisms of ASC quiescence and their role in tissue regeneration.

  20. In Vitro Differentiation of Embryonic and Adult Stem Cells into Hepatocytes: State of the Art

    PubMed Central

    Snykers, Sarah; De Kock, Joery; Rogiers, Vera; Vanhaecke, Tamara

    2009-01-01

    Stem cells are a unique source of self-renewing cells within the human body. Before the end of the last millennium, adult stem cells, in contrast to their embryonic counterparts, were considered to be lineage-restricted cells or incapable of crossing lineage boundaries. However, the unique breakthrough of muscle and liver regeneration by adult bone marrow stem cells at the end of the 1990s ended this long-standing paradigm. Since then, the number of articles reporting the existence of multipotent stem cells in skin, neuronal tissue, adipose tissue, and bone marrow has escalated, giving rise, both in vivo and in vitro, to cell types other than their tissue of origin. The phenomenon of fate reprogrammation and phenotypic diversification remains, though, an enigmatic and rare process. Understanding how to control both proliferation and differentiation of stem cells and their progeny is a challenge in many fields, going from preclinical drug discovery and development to clinical therapy. In this review, we focus on current strategies to differentiate embryonic, mesenchymal(-like), and liver stem/progenitor cells into hepatocytes in vitro. Special attention is paid to intracellular and extracellular signaling, genetic modification, and cell-cell and cell-matrix interactions. In addition, some recommendations are proposed to standardize, optimize, and enrich the in vitro production of hepatocyte-like cells out of stem/progenitor cells. PMID:19056906

  1. Endothelial juxtaposition of distinct adult stem cells activates angiogenesis signaling molecules in endothelial cells.

    PubMed

    Mohammadi, Elham; Nassiri, Seyed Mahdi; Rahbarghazi, Reza; Siavashi, Vahid; Araghi, Atefeh

    2015-12-01

    Efficacy of therapeutic angiogenesis needs a comprehensive understanding of endothelial cell (EC) function and biological factors and cells that interplay with ECs. Stem cells are considered the key components of pro- and anti-angiogenic milieu in a wide variety of physiopathological states, and interactions of EC-stem cells have been the subject of controversy in recent years. In this study, the potential effects of three tissue-specific adult stem cells, namely rat marrow-derived mesenchymal stem cells (rBMSCs), rat adipose-derived stem cells (rADSCs) and rat muscle-derived satellite cells (rSCs), on the endothelial activation of key angiogenic signaling molecules, including VEGF, Ang-2, VEGFR-2, Tie-2, and Tie2-pho, were investigated. Human umbilical vein endothelial cells (HUVECs) and rat lung microvascular endothelial cells (RLMECs) were cocultured with the stem cells or incubated with the stem cell-derived conditioned media on Matrigel. Following HUVEC-stem cell coculture, CD31-positive ECs were flow sorted and subjected to western blotting to analyze potential changes in the expression of the pro-angiogenic signaling molecules. Elongation and co-alignment of the stem cells were seen along the EC tubes in the EC-stem cell cocultures on Matrigel, with cell-to-cell dye communication in the EC-rBMSC cocultures. Moreover, rBMSCs and rADSCs significantly improved endothelial tubulogenesis in both juxtacrine and paracrine manners. These two latter stem cells dynamically up-regulated VEGF, Ang-2, VREGR-2, and Tie-2 but down-regulated Tie2-pho and the Tie2-pho/Tie-2 ratio in HUVECs. Induction of pro-angiogenic signaling in ECs by marrow- and adipose-derived MSCs further indicates the significance of stem cell milieu in angiogenesis dynamics.

  2. Phases I–III Clinical Trials Using Adult Stem Cells

    PubMed Central

    Sanz-Ruiz, Ricardo; Gutiérrez Ibañes, Enrique; Arranz, Adolfo Villa; Fernández Santos, María Eugenia; Fernández, Pedro L. Sánchez; Fernández-Avilés, Francisco

    2010-01-01

    First randomized clinical trials have demonstrated that stem cell therapy can improve cardiac recovery after the acute phase of myocardial ischemia and in patients with chronic ischemic heart disease. Nevertheless, some trials have shown that conflicting results and uncertainties remain in the case of mechanisms of action and possible ways to improve clinical impact of stem cells in cardiac repair. In this paper we will examine the evidence available, analyze the main phase I and II randomized clinical trials and their limitations, discuss the key points in the design of future trials, and depict new directions of research in this fascinating field. PMID:21076533

  3. Pluripotency of adult stem cells derived from human and rat pancreas

    NASA Astrophysics Data System (ADS)

    Kruse, C.; Birth, M.; Rohwedel, J.; Assmuth, K.; Goepel, A.; Wedel, T.

    Adult stem cells are undifferentiated cells found within fully developed tissues or organs of an adult individuum. Until recently, these cells have been considered to bear less self-renewal ability and differentiation potency compared to embryonic stem cells. In recent studies an undifferentiated cell type was found in primary cultures of isolated acini from exocrine pancreas termed pancreatic stellate cells. Here we show that pancreatic stellate-like cells have the capacity of extended self-renewal and are able to differentiate spontaneously into cell types of all three germ layers expressing markers for smooth muscle cells, neurons, glial cells, epithelial cells, chondrocytes and secretory cells (insulin, amylase). Differentiation and subsequent formation of three-dimensional cellular aggregates (organoid bodies) were induced by merely culturing pancreatic stellate-like cells in hanging drops. These cells were developed into stable, long-term, in vitro cultures of both primary undifferentiated cell lines as well as organoid cultures. Thus, evidence is given that cell lineages of endodermal, mesodermal, and ectodermal origin arise spontaneously from a single adult undifferentiated cell type. Based on the present findings it is assumed that pancreatic stellate-like cells are a new class of lineage uncommitted pluripotent adult stem cells with a remarkable self-renewal ability and differentiation potency. The data emphasize the versatility of adult stem cells and may lead to a reappraisal of their use for the treatment of inherited disorders or acquired degenerative diseases.

  4. Empowering Adult Stem Cells for Myocardial Regeneration V2.0: Success in Small Steps

    PubMed Central

    Broughton, Kathleen; Sussman, Mark A.

    2016-01-01

    Much has changed since our survey of the landscape for myocardial regeneration powered by adult stem cells four years ago (Mohsin et al., Empowering adult stem cells for myocardial regeneration. Circ Res. 2011; 109(12):1415–1428) [1]. The intervening years since that first review has witnessed an explosive expansion of studies that advance both understanding and implementation of adult stem cells in promoting myocardial repair. Painstaking research from innumerable laboratories throughout the world is prying open doors that may lead to restoration of myocardial structure and function in the wake of pathologic injury. This global effort has produced deeper mechanistic comprehension coupled with an evolving appreciation for the complexity of myocardial regeneration in the adult context. Undaunted by both known and (as yet) unknown challenges, pursuit of myocardial regenerative medicine mediated by adult stem cell therapy has gathered momentum fueled by tantalizing clues and visionary goals. This concise review takes a somewhat different perspective than our initial treatise, taking stock of the business sector that has become an integral part of the field while concurrently updating “state of affairs” in cutting edge research. Looking retrospectively at advancement over the years as all reviews eventually must, the fundamental lesson to be learned is best explained by Jonatan Mårtensson: “Success will never be a big step in the future. Success is a small step taken just now.” PMID:26941423

  5. Origins of adult pigmentation: diversity in pigment stem cell lineages and implications for pattern evolution

    PubMed Central

    Spiewak, Jessica E.

    2014-01-01

    Summary Teleosts comprise about half of all vertebrate species and exhibit an extraordinary diversity of adult pigment patterns that function in shoaling, camouflage and mate choice and have played important roles in speciation. Here, we review recent studies that have identified several distinct neural crest lineages, with distinct genetic requirements, that give rise to adult pigment cells in fishes. These lineages include post-embryonic, peripheral nerve associated stem cells that generate black melanophores and iridescent iridophores, cells derived directly from embryonic neural crest cells that generate yellow-orange xanthophores, and bipotent stem cells that generate both melanophores and xanthophores. This complexity in adult chromatophore lineages has implications for our understanding of adult traits, melanoma, and the evolutionary diversification of pigment cell lineages and patterns. PMID:25421288

  6. Mitochondria modify exercise-induced development of stem cell-derived neurons in the adult brain.

    PubMed

    Steib, Kathrin; Schäffner, Iris; Jagasia, Ravi; Ebert, Birgit; Lie, D Chichung

    2014-05-07

    Neural stem cells in the adult mammalian hippocampus continuously generate new functional neurons, which modify the hippocampal network and significantly contribute to cognitive processes and mood regulation. Here, we show that the development of new neurons from stem cells in adult mice is paralleled by extensive changes to mitochondrial mass, distribution, and shape. Moreover, exercise-a strong modifier of adult hippocampal neurogenesis-accelerates neuronal maturation and induces a profound increase in mitochondrial content and the presence of mitochondria in dendritic segments. Genetic inhibition of the activity of the mitochondrial fission factor dynamin-related protein 1 (Drp1) inhibits neurogenesis under basal and exercise conditions. Conversely, enhanced Drp1 activity furthers exercise-induced acceleration of neuronal maturation. Collectively, these results indicate that adult hippocampal neurogenesis requires adaptation of the mitochondrial compartment and suggest that mitochondria are targets for enhancing neurogenesis-dependent hippocampal plasticity.

  7. Origins of adult pigmentation: diversity in pigment stem cell lineages and implications for pattern evolution.

    PubMed

    Parichy, David M; Spiewak, Jessica E

    2015-01-01

    Teleosts comprise about half of all vertebrate species and exhibit an extraordinary diversity of adult pigment patterns that function in shoaling, camouflage, and mate choice and have played important roles in speciation. Here, we review studies that have identified several distinct neural crest lineages, with distinct genetic requirements, that give rise to adult pigment cells in fishes. These lineages include post-embryonic, peripheral nerve-associated stem cells that generate black melanophores and iridescent iridophores, cells derived directly from embryonic neural crest cells that generate yellow-orange xanthophores, and bipotent stem cells that generate both melanophores and xanthophores. This complexity in adult chromatophore lineages has implications for our understanding of adult traits, melanoma, and the evolutionary diversification of pigment cell lineages and patterns.

  8. The role of DNA damage repair in aging of adult stem cells.

    PubMed

    Kenyon, Jonathan; Gerson, Stanton L

    2007-01-01

    DNA repair maintains genomic stability and the loss of DNA repair capacity results in genetic instability that may lead to a decline of cellular function. Adult stem cells are extremely important in the long-term maintenance of tissues throughout life. They regenerate and renew tissues in response to damage and replace senescent terminally differentiated cells that no longer function. Oxidative stress, toxic byproducts, reduced mitochondrial function and external exposures all damage DNA through base modification or mis-incorporation and result in DNA damage. As in most cells, this damage may limit the survival of the stem cell population affecting tissue regeneration and even longevity. This review examines the hypothesis that an age-related loss of DNA damage repair pathways poses a significant threat to stem cell survival and longevity. Normal stem cells appear to have strict control of gene expression and DNA replication whereas stem cells with loss of DNA repair may have altered patterns of proliferation, quiescence and differentiation. Furthermore, stem cells with loss of DNA repair may be susceptible to malignant transformation either directly or through the emergence of cancer-prone stem cells. Human diseases and animal models of loss of DNA repair provide longitudinal analysis of DNA repair processes in stem cell populations and may provide links to the physiology of aging.

  9. Female mice lack adult germ-line stem cells but sustain oogenesis using stable primordial follicles.

    PubMed

    Lei, Lei; Spradling, Allan C

    2013-05-21

    Whether or not mammalian females generate new oocytes during adulthood from germ-line stem cells to sustain the ovarian follicle pool has recently generated controversy. We used a sensitive lineage-labeling system to determine whether stem cells are needed in female adult mice to compensate for follicular losses and to directly identify active germ-line stem cells. Primordial follicles generated during fetal life are highly stable, with a half-life during adulthood of 10 mo, and thus are sufficient to sustain adult oogenesis without a source of renewal. Moreover, in normal mice or following germ-cell depletion with Busulfan, only stable, single oocytes are lineage-labeled, rather than cell clusters indicative of new oocyte formation. Even one germ-line stem cell division per 2 wk would have been detected by our method, based on the kinetics of fetal follicle formation. Thus, adult female mice neither require nor contain active germ-line stem cells or produce new oocytes in vivo.

  10. Skin Stem Cells: At the Frontier Between the Laboratory and Clinical Practice. Part 1: Epidermal Stem Cells.

    PubMed

    Pastushenko, I; Prieto-Torres, L; Gilaberte, Y; Blanpain, C

    2015-11-01

    Stem cells are characterized by their ability to self-renew and differentiate into the different cell lineages of their tissue of origin. The discovery of stem cells in adult tissues, together with the description of specific markers for their isolation, has opened up new lines of investigation, expanding the horizons of biomedical research and raising new hope in the treatment of many diseases. In this article, we review in detail the main characteristics of the stem cells that produce the specialized cells of the skin (epidermal, mesenchymal, and melanocyte stem cells) and their potential implications and applications in diseases affecting the skin. Part I deals with the principal characteristics and potential applications of epidermal stem cells in dermatology.

  11. Neural stem cells in the adult ciliary epithelium express GFAP and are regulated by Wnt signaling

    SciTech Connect

    Das, Ani V.; Zhao Xing; James, Jackson; Kim, Min; Cowan, Kenneth H.; Ahmad, Iqbal . E-mail: iahmad@unmc.edu

    2006-01-13

    The identification of neural stem cells with retinal potential in the ciliary epithelium (CE) of the adult mammals is of considerable interest because of their potential for replacing or rescuing degenerating retinal neurons in disease or injury. The evaluation of such a potential requires characterization of these cells with regard to their phenotypic properties, potential, and regulatory mechanisms. Here, we demonstrate that rat CE stem cells/progenitors in neurosphere culture display astrocytic nature in terms of expressing glial intermediate neurofilament protein, GFAP. The GFAP-expressing CE stem cells/progenitors form neurospheres in proliferating conditions and generate neurons when shifted to differentiating conditions. These cells express components of the canonical Wnt pathway and its activation promotes their proliferation. Furthermore, we demonstrate that the activation of the canonical Wnt pathway influences neuronal differentiation of CE stem cells/progenitors in a context dependent manner. Our observations suggest that CE stem cells/progenitors share phenotypic properties and regulatory mechanism(s) with neural stem cells elsewhere in the adult CNS.

  12. Identification of multipotent stem cells from adult dog periodontal ligament.

    PubMed

    Wang, Wen-Jun; Zhao, Yu-Ming; Lin, Bi-Chen; Yang, Jie; Ge, Li-Hong

    2012-08-01

    Periodontal diseases, which are characterized by destruction of the connective tissues responsible for restraining the teeth within the jaw, are the main cause of tooth loss. Periodontal regeneration mediated by human periodontal ligament stem cells (hPDLSCs) may offer an alternative strategy for the treatment of periodontal disease. Dogs are a widely used large-animal model for the study of periodontal-disease progression, tissue regeneration, and dental implants, but little attention has been paid to the identification of the cells involved in this species. This study aimed to characterize stem cells isolated from canine periodontal ligament (cPDLSCs). The cPDLSCs, like hPDLSCs, showed clonogenic capability and expressed the mesenchymal stem cell markers STRO-1, CD146, and CD105, but not CD34. After induction of osteogenesis, cPDLSCs showed calcium accumulation in vitro. Moreover, cPDLSCs also showed both adipogenic and chondrogenic potential. Compared with cell-free controls, more cementum/periodontal ligament-like structures were observed in CB-17/SCID mice into which cPDLSCs had been transplanted. These results suggest that cPDLSCs are clonogenic, highly proliferative, and have multidifferentiation potential, and that they could be used as a new cellular therapeutic approach to facilitate successful and more predictable regeneration of periodontal tissue using a canine model of periodontal disease.

  13. Mesenchymal stem cells from the outer ear: a novel adult stem cell model system for the study of adipogenesis.

    PubMed

    Rim, Jong-Seop; Mynatt, Randall L; Gawronska-Kozak, Barbara

    2005-07-01

    Adipocytes arise from multipotent stem cells of mesodermal origin, which also give rise to the muscle, bone, and cartilage lineages. However, signals and early molecular events that commit multipotent stem cells into the adipocyte lineage are not well established mainly due to lack of an adequate model system. We have identified a novel source of adult stem cells from the external murine ears referred to here as an ear mesenchymal stem cells (EMSC). EMSC have been isolated from several standard and mutant strains of mice. They are self-renewing, clonogenic, and multipotent, since they give rise to osteocytes, chondrocytes, and adipocytes. The in vitro characterization of EMSC indicates very facile adipogenic differentiation. Morphological, histochemical, and molecular analysis after the induction of differentiation showed that EMSC maintain adipogenic potentials up to fifth passage. A comparison of EMSC to the stromal-vascular (S-V) fraction of fat depots, under identical culture conditions (isobutyl-methylxanthine, dexamethasone, and insulin), revealed much more robust and consistent adipogenesis in EMSC than in the S-V fraction. In summary, we show that EMSC can provide a novel, easily obtainable, primary culture model for the study of adipogenesis.

  14. Genomic selection for quantitative adult plant stem rust resistance in wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Quantitative adult plant resistance (APR) to stem rust (Puccinia graminis f. sp. tritici) is an important breeding target in wheat (Triticum aestivum L.) and a potential target for genomic selection (GS). To evaluate the relative importance of known APR loci in applying genomic selection, we charact...

  15. zebraflash transgenic lines for in vivo bioluminescence imaging of stem cells and regeneration in adult zebrafish.

    PubMed

    Chen, Chen-Hui; Durand, Ellen; Wang, Jinhu; Zon, Leonard I; Poss, Kenneth D

    2013-12-01

    The zebrafish has become a standard model system for stem cell and tissue regeneration research, based on powerful genetics, high tissue regenerative capacity and low maintenance costs. Yet, these studies can be challenged by current limitations of tissue visualization techniques in adult animals. Here we describe new imaging methodology and present several ubiquitous and tissue-specific luciferase-based transgenic lines, which we have termed zebraflash, that facilitate the assessment of regeneration and engraftment in freely moving adult zebrafish. We show that luciferase-based live imaging reliably estimates muscle quantity in an internal organ, the heart, and can longitudinally follow cardiac regeneration in individual animals after major injury. Furthermore, luciferase-based detection enables visualization and quantification of engraftment in live recipients of transplanted hematopoietic stem cell progeny, with advantages in sensitivity and gross spatial resolution over fluorescence detection. Our findings present a versatile resource for monitoring and dissecting vertebrate stem cell and regeneration biology.

  16. Strategies to enhance umbilical cord blood stem cell engraftment in adult patients

    PubMed Central

    Delaney, Colleen; Ratajczak, Mariusz Z; Laughlin, Mary J

    2010-01-01

    Umbilical cord blood (UCB) has been used successfully as a source of hematopoietic stem cells (HSCs) for allogeneic transplantation in children and adults in the treatment of hematologic diseases. However, compared with marrow or mobilized peripheral blood stem cell grafts from adult donors, significant delays in the rates and kinetics of neutrophil and platelet engraftment are noted after UCB transplant. These differences relate in part to the reduced numbers of HSCs in UCB grafts. To improve the rates and kinetics of engraftment of UCB HSC, several strategies have been proposed, including ex vivo expansion of UCB HSCs, addition of third-party mesenchymal cells, intrabone delivery of HSCs, modulation of CD26 expression, and infusion of two UCB grafts. This article will focus on ex vivo expansion of UCB HSCs and strategies to enhance UCB homing as potential solutions to overcome the problem of low stem cell numbers in a UCB graft. PMID:20835351

  17. Fetal programming of adult Leydig cell function by androgenic effects on stem/progenitor cells.

    PubMed

    Kilcoyne, Karen R; Smith, Lee B; Atanassova, Nina; Macpherson, Sheila; McKinnell, Chris; van den Driesche, Sander; Jobling, Matthew S; Chambers, Thomas J G; De Gendt, Karel; Verhoeven, Guido; O'Hara, Laura; Platts, Sophie; Renato de Franca, Luiz; Lara, Nathália L M; Anderson, Richard A; Sharpe, Richard M

    2014-05-06

    Fetal growth plays a role in programming of adult cardiometabolic disorders, which in men, are associated with lowered testosterone levels. Fetal growth and fetal androgen exposure can also predetermine testosterone levels in men, although how is unknown, because the adult Leydig cells (ALCs) that produce testosterone do not differentiate until puberty. To explain this conundrum, we hypothesized that stem cells for ALCs must be present in the fetal testis and might be susceptible to programming by fetal androgen exposure during masculinization. To address this hypothesis, we used ALC ablation/regeneration to identify that, in rats, ALCs derive from stem/progenitor cells that express chicken ovalbumin upstream promoter transcription factor II. These stem cells are abundant in the fetal testis of humans and rodents, and lineage tracing in mice shows that they develop into ALCs. The stem cells also express androgen receptors (ARs). Reduction in fetal androgen action through AR KO in mice or dibutyl phthalate (DBP) -induced reduction in intratesticular testosterone in rats reduced ALC stem cell number by ∼40% at birth to adulthood and induced compensated ALC failure (low/normal testosterone and elevated luteinizing hormone). In DBP-exposed males, this failure was probably explained by reduced testicular steroidogenic acute regulatory protein expression, which is associated with increased histone methylation (H3K27me3) in the proximal promoter. Accordingly, ALCs and ALC stem cells immunoexpressed increased H3K27me3, a change that was also evident in ALC stem cells in fetal testes. These studies highlight how a key component of male reproductive development can fundamentally reprogram adult hormone production (through an epigenetic change), which might affect lifetime disease risk.

  18. Stroke Increases Neural Stem Cells and Angiogenesis in the Neurogenic Niche of the Adult Mouse

    PubMed Central

    Zhang, Rui Lan; Chopp, Michael; Roberts, Cynthia; Liu, Xianshuang; Wei, Min; Nejad-Davarani, Siamak P.; Wang, Xinli; Zhang, Zheng Gang

    2014-01-01

    The unique cellular and vascular architecture of the adult ventricular-subventricular zone (V/SVZ) neurogenic niche plays an important role in regulating neural stem cell function. However, the in vivo identification of neural stem cells and their relationship to blood vessels within this niche in response to stroke remain largely unknown. Using whole-mount preparation of the lateral ventricle wall, we examined the architecture of neural stem cells and blood vessels in the V/SVZ of adult mouse over the course of 3 months after onset of focal cerebral ischemia. Stroke substantially increased the number of glial fibrillary acidic protein (GFAP) positive neural stem cells that are in contact with the cerebrospinal fluid (CSF) via their apical processes at the center of pinwheel structures formed by ependymal cells residing in the lateral ventricle. Long basal processes of these cells extended to blood vessels beneath the ependymal layer. Moreover, stroke increased V/SVZ endothelial cell proliferation from 2% in non-ischemic mice to 12 and 15% at 7 and 14 days after stroke, respectively. Vascular volume in the V/SVZ was augmented from 3% of the total volume prior to stroke to 6% at 90 days after stroke. Stroke-increased angiogenesis was closely associated with neuroblasts that expanded to nearly encompass the entire lateral ventricular wall in the V/SVZ. These data indicate that stroke induces long-term alterations of the neural stem cell and vascular architecture of the adult V/SVZ neurogenic niche. These post-stroke structural changes may provide insight into neural stem cell mediation of stroke-induced neurogenesis through the interaction of neural stem cells with proteins in the CSF and their sub-ependymal neurovascular interaction. PMID:25437857

  19. The novel steroidal alkaloids dendrogenin A and B promote proliferation of adult neural stem cells

    SciTech Connect

    Khalifa, Shaden A.M.; Medina, Philippe de; Erlandsson, Anna; El-Seedi, Hesham R.; Silvente-Poirot, Sandrine; Poirot, Marc

    2014-04-11

    Highlights: • Dendrogenin A and B are new aminoalkyl oxysterols. • Dendrogenins stimulated neural stem cells proliferation. • Dendrogenins induce neuronal outgrowth from neurospheres. • Dendrogenins provide new therapeutic options for neurodegenerative disorders. - Abstract: Dendrogenin A (DDA) and dendrogenin B (DDB) are new aminoalkyl oxysterols which display re-differentiation of tumor cells of neuronal origin at nanomolar concentrations. We analyzed the influence of dendrogenins on adult mice neural stem cell proliferation, sphere formation and differentiation. DDA and DDB were found to have potent proliferative effects in neural stem cells. Additionally, they induce neuronal outgrowth from neurospheres during in vitro cultivation. Taken together, our results demonstrate a novel role for dendrogenins A and B in neural stem cell proliferation and differentiation which further increases their likely importance to compensate for neuronal cell loss in the brain.

  20. Large-scale live imaging of adult neural stem cells in their endogenous niche.

    PubMed

    Dray, Nicolas; Bedu, Sébastien; Vuillemin, Nelly; Alunni, Alessandro; Coolen, Marion; Krecsmarik, Monika; Supatto, Willy; Beaurepaire, Emmanuel; Bally-Cuif, Laure

    2015-10-15

    Live imaging of adult neural stem cells (aNSCs) in vivo is a technical challenge in the vertebrate brain. Here, we achieve long-term imaging of the adult zebrafish telencephalic neurogenic niche and track a population of >1000 aNSCs over weeks, by taking advantage of fish transparency at near-infrared wavelengths and of intrinsic multiphoton landmarks. This methodology enables us to describe the frequency, distribution and modes of aNSCs divisions across the entire germinal zone of the adult pallium, and to highlight regional differences in these parameters.

  1. How electromagnetic fields can influence adult stem cells: positive and negative impacts.

    PubMed

    Maziarz, Aleksandra; Kocan, Beata; Bester, Mariusz; Budzik, Sylwia; Cholewa, Marian; Ochiya, Takahiro; Banas, Agnieszka

    2016-04-18

    The electromagnetic field (EMF) has a great impact on our body. It has been successfully used in physiotherapy for the treatment of bone disorders and osteoarthritis, as well as for cartilage regeneration or pain reduction. Recently, EMFs have also been applied in in vitro experiments on cell/stem cell cultures. Stem cells reside in almost all tissues within the human body, where they exhibit various potential. These cells are of great importance because they control homeostasis, regeneration, and healing. Nevertheless, stem cells when become cancer stem cells, may influence the pathological condition. In this article we review the current knowledge on the effects of EMFs on human adult stem cell biology, such as proliferation, the cell cycle, or differentiation. We present the characteristics of the EMFs used in miscellaneous assays. Most research has so far been performed during osteogenic and chondrogenic differentiation of mesenchymal stem cells. It has been demonstrated that the effects of EMF stimulation depend on the intensity and frequency of the EMF and the time of exposure to it. However, other factors may affect these processes, such as growth factors, reactive oxygen species, and so forth. Exploration of this research area may enhance the development of EMF-based technologies used in medical applications and thereby improve stem cell-based therapy and tissue engineering.

  2. A mystery unraveled: nontumorigenic pluripotent stem cells in human adult tissues

    PubMed Central

    Simerman, Ariel A; Perone, Marcelo J; Gimeno, María L; Dumesic, Daniel A; Chazenbalk, Gregorio D

    2014-01-01

    Introduction: Embryonic stem cells and induced pluripotent stem cells have emerged as the gold standard of pluripotent stem cells and the class of stem cell with the highest potential for contribution to regenerative and therapeutic application; however, their translational use is often impeded by teratoma formation, commonly associated with pluripotency. We discuss a population of nontumorigenic pluripotent stem cells, termed Multilineage Differentiating Stress Enduring (Muse) cells, which offer an innovative and exciting avenue of exploration for the potential treatment of various human diseases. Areas covered: This review discusses the origin of Muse cells, describes in detail their various unique characteristics, and considers future avenues of their application and investigation with respect to what is currently known of adult pluripotent stem cells in scientific literature. We begin by defining cell potency, then discuss both mesenchymal and various reported populations of pluripotent stem cells, and finally delve into Muse cells and the characteristics that set them apart from their contemporaries. Expert opinion: Muse cells derived from adipose tissue (Muse-AT) are efficiently, routinely and painlessly isolated from human lipoaspirate material, exhibit tripoblastic differentiation both spontaneously and under media-specific induction, and do not form teratomas. We describe qualities specific to Muse-AT cells and their potential impact on the field of regenerative medicine and cell therapy. PMID:24745973

  3. Isolating intestinal stem cells from adult Drosophila midguts by FACS to study stem cell behavior during aging.

    PubMed

    Tauc, Helen M; Tasdogan, Alpaslan; Pandur, Petra

    2014-12-16

    Aging tissue is characterized by a continuous decline in functional ability. Adult stem cells are crucial in maintaining tissue homeostasis particularly in tissues that have a high turnover rate such as the intestinal epithelium. However, adult stem cells are also subject to aging processes and the concomitant decline in function. The Drosophila midgut has emerged as an ideal model system to study molecular mechanisms that interfere with the intestinal stem cells' (ISCs) ability to function in tissue homeostasis. Although adult ISCs can be easily identified and isolated from midguts of young flies, it has been a major challenge to study endogenous molecular changes of ISCs during aging. This is due to the lack of a combination of molecular markers suitable to isolate ISCs from aged intestines. Here we propose a method that allows for successful dissociation of midgut tissue into living cells that can subsequently be separated into distinct populations by FACS. By using dissociated cells from the esg-Gal4, UAS-GFP fly line, in which both ISCs and the enteroblast (EB) progenitor cells express GFP, two populations of cells are distinguished based on different GFP intensities. These differences in GFP expression correlate with differences in cell size and granularity and represent enriched populations of ISCs and EBs. Intriguingly, the two GFP-positive cell populations remain distinctly separated during aging, presenting a novel technique for identifying and isolating cell populations enriched for either ISCs or EBs at any time point during aging. The further analysis, for example transcriptome analysis, of these particular cell populations at various time points during aging is now possible and this will facilitate the examination of endogenous molecular changes that occur in these cells during aging.

  4. Apple ethanol extract promotes proliferation of human adult stem cells, which involves the regenerative potential of stem cells.

    PubMed

    Lee, Jienny; Shin, Moon Sam; Kim, Mi Ok; Jang, Sunghee; Oh, Sae Woong; Kang, Mingyeong; Jung, Kwangseon; Park, Yong Seek; Lee, Jongsung

    2016-09-01

    Tissue regeneration using adult stem cells (ASCs) has significant potential as a novel treatment for many degenerative diseases. Previous studies have established that age negatively affects the proliferation status and differentiation potential of ASCs, suggesting a possible limitation in their potential therapeutic use. Therefore, we hypothesized that apple extract might exert beneficial effects on ASCs. The specific objectives were to investigate the proliferative effect of apple ethanol extract on human adipose tissue-derived mesenchymal stem cells (ADSCs) and human cord blood-derived mesenchymal stem cells (CB-MSCs), and identify the possible molecular mechanisms. Apple extract promoted proliferation of ADSCs and CB-MSCs as determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and Click-iT 5-ethynyl-2'-deoxyuridine flow cytometry assays. In addition, phosphorylation of p44/42 MAPK (ERK), mammalian target of rapamycin (mTOR), p70 S6 kinase (p70S6K), S6 ribosomal protein (S6RP), eukaryotic initiation factor (eIF) 4B and eIF4E was induced stepwise in ADSCs. Furthermore, apple extract significantly induced the production of vascular endothelial growth factor and interleukin-6 in both ADSCs and CB-MSCs. Similarly, apple extract-induced phosphorylation of the mTOR/p70S6K/S6RP/eIF4B/eIF4E pathway was blocked by pretreatment with PD98059, a specific ERK inhibitor. These results indicate that apple extract-induced proliferation of ADSCs under serum-free conditions is mediated by ERK-dependent cytokine production. Moreover, the beneficial effect of apple extract on proliferation of ASCs may overcome the limitation in therapeutic use of stem cells in tissue regeneration and maintenance of stem cell homeostasis.

  5. A hypothesis for an embryonic origin of pluripotent Oct-4(+) stem cells in adult bone marrow and other tissues.

    PubMed

    Ratajczak, M Z; Machalinski, B; Wojakowski, W; Ratajczak, J; Kucia, M

    2007-05-01

    Accumulating evidence demonstrates that adult tissues contain a population of stem cells that express early developmental markers such as stage-specific embryonic antigen and transcription factors Oct-4 and Nanog. These are the markers characteristic for embryonic stem cells, epiblast stem cells and primordial germ cells. The presence of these stem cells in adult tissues including bone marrow, epidermis, bronchial epithelium, myocardium, pancreas and testes supports the concept that adult tissues contain some population of pluripotent stem cells that is deposited in embryogenesis during early gastrulation. In this review we will discuss these data and present a hypothesis that these cells could be direct descendants of the germ lineage. The germ lineage in order to pass genes on to the next generations creates soma and thus becomes a 'mother lineage' for all somatic cell lineages present in the adult body.

  6. Biological characteristics of mouse skin melanocytes.

    PubMed

    Shi, Zhanquan; Ji, Kaiyuan; Yang, Shanshan; Zhang, Junzhen; Yao, Jianbo; Dong, Changsheng; Fan, Ruiwen

    2016-04-01

    The objective of this research was to evaluate the optimal passage number according to the biological characteristics of mouse skin melanocytes from different passages. Skin punch biopsies harvested from the dorsal region of 2-day old mice were used to establish melanocyte cultures. The cells from passage 4, 7, 10 and 13 were collected and evaluated for their melanogenic activity. Histochemical staining for tyrosinase (TYR) activity and immunostaining for the melanocyte specific markers including S-100 antigen, TYR, tyrosinase related protein 1 (TYRP1), tyrosinase related protein 2 (TYRP2) and micropthalmia associated transcription factor (MITF) confirmed purity and melanogenic capacity of melanocytes from different passages, with better melanogenic activity of passage 10 and 13 cells being observed. Treatment of passage 13 melanocytes with α-melanocyte stimulating hormone (α-MSH) showed increased expression of MITF, TYR and TYRP2 mRNA. However, considering the TYR mRNA dramatically high expression which is the characteristics of melanoma cells, melanocytes from passage 10 was the optimal passage number for the further research. Our results demonstrate culture of pure populations of mouse melanocytes to at least 10 passages and illustrate the potential utility of passage 10 cells for studies of intrinsic and extrinsic regulation of genes controlling pigmentation and coat color in mouse.

  7. GI tract tumors with melanocytic differentiation.

    PubMed

    Karamchandani, Dipti M; Patil, Deepa T; Goldblum, John R

    2013-11-01

    Gastrointestinal (GI) tract tumors with melanocytic differentiation may present significant diagnostic challenges both for the pathologist and the clinician. This comprehensive review discusses the relatively common as well as rare entities that have melanocytic differentiation in the GI tract. Clinical, histologic, immunohistochemical and molecular features are discussed along with prognosis and differential diagnosis.

  8. Micropatterning control of tubular commitment in human adult renal stem cells.

    PubMed

    Sciancalepore, Anna G; Portone, Alberto; Moffa, Maria; Persano, Luana; De Luca, Maria; Paiano, Aurora; Sallustio, Fabio; Schena, Francesco P; Bucci, Cecilia; Pisignano, Dario

    2016-07-01

    The treatment of renal injury by autologous, patient-specific adult stem cells is still an unmet need. Unsolved issues remain the spatial integration of stem cells into damaged areas of the organ, the commitment in the required cell type and the development of improved bioengineered devices. In this respect, biomaterials and architectures have to be specialized to control stem cell differentiation. Here, we perform an extensive study on micropatterned extracellular matrix proteins, which constitute a simple and non-invasive approach to drive the differentiation of adult renal progenitor/stem cells (ARPCs) from human donors. ARPCs are interfaced with fibronectin (FN) micropatterns, in the absence of exogenous chemicals or cellular reprogramming. We obtain the differentiation towards tubular cells of ARPCs cultured in basal medium conditions, the tubular commitment thus being specifically induced by micropatterned substrates. We characterize the stability of the tubular differentiation as well as the induction of a polarized phenotype in micropatterned ARPCs. Thus, the developed cues, driving the functional commitment of ARPCs, offer a route to recreate the microenvironment of the stem cell niche in vitro, that may serve, in perspective, for the development of ARPC-based bioengineered devices.

  9. Comparative analysis of mesenchymal stem cells from adult mouse adipose, muscle, and fetal muscle.

    PubMed

    Lei, Hulong; Yu, Bing; Huang, Zhiqing; Yang, Xuerong; Liu, Zehui; Mao, Xiangbing; Tian, Gang; He, Jun; Han, Guoquan; Chen, Hong; Mao, Qian; Chen, Daiwen

    2013-02-01

    Recently, increasing evidence supports that adult stem cells are the part of a natural system for tissue growth and repair. This study focused on the differences of mesenchymal stem cells from adult adipose (ADSCs), skeletal muscle (MDSCs) and fetal muscle (FMSCs) in biological characteristics, which is the key to cell therapy success. Stem cell antigen 1 (Sca-1) expression of MDSCs and FMSCs at passage 3 was two times more than that at passage 1 (P < 0.0001). After 28-day myogenic induction, higher expression levels of skeletal muscle-specific genes were observed in MDSCs than FMSCs (P < 0.01), and the lowest expression levels were demonstrated in ADSCs among three cells (P < 0.01). Besides, M-Cad and MyHC expressions in ADSCs were not detected by immunofluorescence or real-time quantitative PCR. Furthermore, after 14 days adipogenic induction, PPARγ2, LPL and aP2 mRNA expressions were higher in ADSCs vs. MDSCs (P < 0.01). Besides, MSCs from adult or fetal muscle expressed higher OCN and OPN than ADSCs after 28 days osteogenic induction (P < 0.01). Taken together, our results suggested that cell source and developmental stage had great impacts on biological properties of mesenchymal stem cells, and proper consideration of all the issues is necessary.

  10. Profiling of Sox4-dependent transcriptome in skin links tumour suppression and adult stem cell activation.

    PubMed

    Foronda, Miguel; Morgado-Palacin, Lucia; Gómez-López, Gonzalo; Domínguez, Orlando; Pisano, David G; Blasco, Maria A

    2015-12-01

    Adult stem cells (ASCs) reside in specific niches in a quiescent state in adult mammals. Upon specific cues they become activated and respond by self-renewing and differentiating into newly generated specialised cells that ensure appropriate tissue fitness. ASC quiescence also serves as a tumour suppression mechanism by hampering cellular transformation and expansion (White AC et al., 2014). Some genes restricted to early embryonic development and adult stem cell niches are often potent modulators of stem cell quiescence, and derailed expression of these is commonly associated to cancer (Vervoort SJ et al., 2013). Among them, it has been shown that recommissioned Sox4 expression facilitates proliferation, survival and migration of malignant cells. By generating a conditional Knockout mouse model in stratified epithelia (Sox4 (cKO) mice), we demonstrated a delayed plucking-induced Anagen in the absence of Sox4. Skin global transcriptome analysis revealed a prominent defect in the induction of transcriptional networks that control hair follicle stem cell (HFSC) activation such as those regulated by Wnt/Ctnnb1, Shh, Myc or Sox9, cell cycle and DNA damage response-associated pathways. Besides, Sox4 (cKO) mice are resistant to skin carcinogenesis, thus linking Sox4 to both normal and pathological HFSC activation (Foronda M et al., 2014). Here we provide additional details on the analysis of Sox4-regulated transcriptome in Telogen and Anagen skin. The raw and processed microarray data is deposited in GEO under GSE58155.

  11. Differentiation and characteristics of undifferentiated mesenchymal stem cells originating from adult premolar periodontal ligaments

    PubMed Central

    Kwon, Dae-Woo; Im, Insook; Kim, Yong-Deok; Hwang, Dae-Seok; Holliday, L Shannon; Donatelli, Richard E; Son, Woo-Sung; Jun, Eun-Sook

    2012-01-01

    Objective The purpose of this study was to investigate the isolation and characterization of multipotent human periodontal ligament (PDL) stem cells and to assess their ability to differentiate into bone, cartilage, and adipose tissue. Methods PDL stem cells were isolated from 7 extracted human premolar teeth. Human PDL cells were expanded in culture, stained using anti-CD29, -CD34, -CD44, and -STRO-1 antibodies, and sorted by fluorescent activated cell sorting (FACS). Gingival fibroblasts (GFs) served as a positive control. PDL stem cells and GFs were cultured using standard conditions conducive for osteogenic, chondrogenic, or adipogenic differentiation. Results An average of 152.8 ± 27.6 colony-forming units was present at day 7 in cultures of PDL stem cells. At day 4, PDL stem cells exhibited a significant increase in proliferation (p < 0.05), reaching nearly double the proliferation rate of GFs. About 5.6 ± 4.5% of cells in human PDL tissues were strongly STRO-1-positive. In osteogenic cultures, calcium nodules were observed by day 21 in PDL stem cells, which showed more intense calcium staining than GF cultures. In adipogenic cultures, both cell populations showed positive Oil Red O staining by day 21. Additionally, in chondrogenic cultures, PDL stem cells expressed collagen type II by day 21. Conclusions The PDL contains multipotent stem cells that have the potential to differentiate into osteoblasts, chondrocytes, and adipocytes. This adult PDL stem cell population can be utilized as potential sources of PDL in tissue engineering applications. PMID:23323245

  12. Inflammatory cues acting on the adult intestinal stem cells and the early onset of cancer (Review)

    PubMed Central

    DE LERMA BARBARO, A.; PERLETTI, G.; BONAPACE, I.M.; MONTI, E.

    2014-01-01

    The observation that cancer often arises at sites of chronic inflammation has prompted the idea that carcinogenesis and inflammation are deeply interwoven. In fact, the current literature highlights a role for chronic inflammation in virtually all the steps of carcinogenesis, including tumor initiation, promotion and progression. The aim of the present article is to review the current literature on the involvement of chronic inflammation in the initiation step and in the very early phases of tumorigenesis, in a type of cancer where adult stem cells are assumed to be the cells of origin of neoplasia. Since the gastrointestinal tract is regarded as the best-established model system to address the liaison between chronic inflammation and neoplasia, the focus of this article will be on intestinal cancer. In fact, the anatomy of the intestinal epithelial lining is uniquely suited to study adult stem cells in their niche, and the bowel crypt is an ideal developmental biology system, as proliferation, differentiation and cell migration are all distributed linearly along the long axis of the crypt. Moreover, crypt stem cells are regarded today as the most likely targets of neoplastic transformation in bowel cancer. More specifically, the present review addresses the molecular mechanisms whereby a state of chronic inflammation could trigger the neoplastic process in the intestine, focusing on the generation of inflammatory cues evoking enhanced proliferation in cells not initiated but at risk of neoplastic transformation because of their stemness. Novel experimental approaches, based on triggering an inflammatory stimulus in the neighbourhood of adult intestinal stem cells, are warranted to address some as yet unanswered questions. A possible approach, the targeted transgenesis of Paneth cells, may be aimed at ‘hijacking’ the crypt stem cell niche from a status characterized by the maintenance of homeostasis to local chronic inflammation, with the prospect of initiating

  13. [Molecular diagnosis of melanocytic tumors].

    PubMed

    Bauer, J

    2016-01-01

    Melanoma therapy has undergone a paradigm shift. Classic chemotherapies with poor treatment responses have been replaced by modern immune checkpoint blockades and targeted therapies with excellent responses. The latter require precise diagnosis of mutations in the melanoma genome as molecular targets for the small molecules. The diagnosis of melanomas has also been supplemented by molecular techniques. Differential diagnosis of melanoma and melanoma simulators such as atypical Spitz nevi can be supported by fluorescence in situ hybridization (FISH) and comparative genomic hybridization (CGH). Here we review the indications and methods for molecular diagnosis of melanocytic tumors.

  14. Evolutionary dynamics of adult stem cells: Comparison of random and immortal-strand segregation mechanisms

    NASA Astrophysics Data System (ADS)

    Tannenbaum, Emmanuel; Sherley, James L.; Shakhnovich, Eugene I.

    2005-04-01

    This paper develops a point-mutation model describing the evolutionary dynamics of a population of adult stem cells. Such a model may prove useful for quantitative studies of tissue aging and the emergence of cancer. We consider two modes of chromosome segregation: (1) random segregation, where the daughter chromosomes of a given parent chromosome segregate randomly into the stem cell and its differentiating sister cell and (2) “immortal DNA strand” co-segregation, for which the stem cell retains the daughter chromosomes with the oldest parent strands. Immortal strand co-segregation is a mechanism, originally proposed by [Cairns Nature (London) 255, 197 (1975)], by which stem cells preserve the integrity of their genomes. For random segregation, we develop an ordered strand pair formulation of the dynamics, analogous to the ordered strand pair formalism developed for quasispecies dynamics involving semiconservative replication with imperfect lesion repair (in this context, lesion repair is taken to mean repair of postreplication base-pair mismatches). Interestingly, a similar formulation is possible with immortal strand co-segregation, despite the fact that this segregation mechanism is age dependent. From our model we are able to mathematically show that, when lesion repair is imperfect, then immortal strand co-segregation leads to better preservation of the stem cell lineage than random chromosome segregation. Furthermore, our model allows us to estimate the optimal lesion repair efficiency for preserving an adult stem cell population for a given period of time. For human stem cells, we obtain that mispaired bases still present after replication and cell division should be left untouched, to avoid potentially fixing a mutation in both DNA strands.

  15. Adult stem cell therapy and heart failure, 2000 to 2016: a systematic review

    PubMed Central

    Nguyen, Patricia K.; Rhee, June-Wha; Wu, Joseph C.

    2017-01-01

    Importance Stem cell therapy is a promising treatment strategy for patients with heart failure, which accounts for over 10% of deaths in the U.S. annually. Despite over a decade of research, further investigation is still needed to determine whether stem cell regenerative therapy is clinically effective and can be routinely implemented in clinical practice. Objective The purpose of this review is to describe the current progress in cardiac stem cell regenerative therapy using adult stem cells and highlight the merits and limitations of clinical trials performed to date. Evidence Review Information for this review was obtained through a search of PubMed and the Cochrane database for English language studies published between January 1, 2000 and April 20, 2016. Twenty-nine randomized clinical trials and 7 systematic reviews and meta-analyses were included in this review. Findings Although adult stem cells were once believed to have the ability to create new heart tissue or grow blood vessels, preclinical studies suggest instead that these cells release cardio-protective paracrine factors that activate endogenous pathways, leading to myocardial repair. Subsequent randomized controlled clinical trials, the majority of which used autologous bone marrow mononuclear cells, have found only a modest benefit in patients receiving stem cell therapy. The lack of a significant benefit may result from variations in trial methodology, discrepancies in reporting, and an over-reliance on surrogate endpoints. Conclusions and Relevance Although stem cell therapy for cardiovascular disease is not yet ready for routine clinical application, significant progress continues to be made. Physicians should be aware of the current status of this treatment so that they can better inform their patients who may be in search of alternative therapies. PMID:27557438

  16. Quiescent adult neural stem cells are exceptionally sensitive to cosmic radiation

    PubMed Central

    Encinas, Juan M.; Vazquez, Marcelo E.; Switzer, Robert C.; Chamberland, Dennis W.; Nick, Harry; Levine, Howard G.; Scarpa, Philip J.; Enikolopov, Grigori; Steindler, Dennis A.

    2012-01-01

    Generation of new neurons in the adult brain, a process that is likely to be essential for learning, memory, and mood regulation, is impaired by radiation. Therefore, radiation exposure might have not only such previously expected consequences as increased probability of developing cancer, but might also impair cognitive function and emotional stability. Radiation exposure is encountered in settings ranging from cancer therapy to space travel; evaluating the neurogenic risks of radiation requires identifying the at-risk populations of stem and progenitor cells in the adult brain. Here we have used a novel reporter mouse line to find that early neural progenitors are selectively affected by conditions simulating the space radiation environment. This is reflected both in a decrease in the number of these progenitors in the neurogenic regions and in an increase in the number of dying cells in these regions. Unexpectedly, we found that quiescent neural stem cells, rather than their rapidly dividing progeny, are most sensitive to radiation. Since these stem cells are responsible for adult neurogenesis, their death would have a profound impact on the production of new neurons in the irradiated adult brain. Our finding raises an important concern about cognitive and emotional risks associated with radiation exposure. PMID:18076878

  17. Plastic adult stem cells: will they graduate from the school of hard knocks?

    PubMed

    Alison, Malcolm R; Poulsom, Richard; Otto, William R; Vig, Pamela; Brittan, Mairi; Direkze, Natalie C; Preston, Sean L; Wright, Nicholas A

    2003-02-15

    Notwithstanding the fact that adult bone marrow cell engraftment to epithelial organs seems a somewhat uncommon event, there is no doubt it does occur, and under appropriate conditions of a strong and positive selection pressure these cells will expand clonally and make a significant contribution to tissue replacement. Likewise, bone-marrow-derived cells can be amplified in vitro and differentiated into a multitude of tissues. These in essence are the goals of regenerative medicine using any source of stem cells, be it embryonic or adult. Despite such irrefutable evidence of what is possible, a veritable chorus of detractors of adult stem cell plasticity has emerged, some doubting its very existence, motivated perhaps by more than a little self-interest. The issues that have led to this state of affairs have included the inability to reproduce certain widely quoted data, one case where the apparent transdifferentiation was due to contamination of the donor tissue with haematopoietic cells and, most notoriously, extrapolating from the behaviour of embryonic stem cells to suggest that adult bone marrow cells simply fuse with other cells and adopt their phenotype. While these issues need resolving, slamming this whole new field because not everything is crystal clear is not good science. The fact that a phenomenon is quite rare in no way mitigates against its very existence: asteroid collisions with the Earth are rare, but try telling the dinosaurs they do not occur! When such events do occur (transdifferentiation or collision), they certainly can make an impact.

  18. Empowering Adult Stem Cells for Myocardial Regeneration V2.0: Success in Small Steps.

    PubMed

    Broughton, Kathleen M; Sussman, Mark A

    2016-03-04

    Much has changed since our survey of the landscape for myocardial regeneration powered by adult stem cells 4 years ago.(1) The intervening years since that first review has witnessed an explosive expansion of studies that advance both understanding and implementation of adult stem cells in promoting myocardial repair. Painstaking research from innumerable laboratories throughout the world is prying open doors that may lead to restoration of myocardial structure and function in the wake of pathological injury. This global effort has produced deeper mechanistic comprehension coupled with an evolving appreciation for the complexity of myocardial regeneration in the adult context. Undaunted by both known and (as yet) unknown challenges, pursuit of myocardial regenerative medicine mediated by adult stem cell therapy has gathered momentum fueled by tantalizing clues and visionary goals. This concise review takes a somewhat different perspective than our initial treatise, taking stock of the business sector that has become an integral part of the field while concurrently updating state of affairs in cutting edge research. Looking retrospectively at advancement over the years as all reviews eventually must, the fundamental lesson to be learned is best explained by Jonatan Mårtensson: "Success will never be a big step in the future. Success is a small step taken just now."

  19. The sexual identity of adult intestinal stem cells controls organ size and plasticity

    PubMed Central

    Hudry, Bruno; Khadayate, Sanjay; Miguel-Aliaga, Irene

    2016-01-01

    SUMMARY Sex differences in physiology and disease susceptibility are commonly attributed to developmental and/or hormonal factors, but there is increasing realisation that cell-intrinsic mechanisms play important and persistent roles1,2. Here we use the Drosophila melanogaster intestine to investigate the nature and significance of cellular sex in an adult somatic organ in vivo. We find that the adult intestinal epithelium is a cellular mosaic of different sex differentiation pathways, and displays extensive sex differences in expression of genes with roles in growth and metabolism. Cell-specific reversals of the sexual identity of adult intestinal stem cells uncover its key roles in controlling organ size, its reproductive plasticity and its response to genetically induced tumours. Unlike previous examples of sexually dimorphic somatic stem cell activity, the sex differences in intestinal stem cell behaviour arise from intrinsic mechanisms, which control cell cycle duration and involve a new doublesex- and fruitless-independent branch of the sex differentiation pathway downstream of transformer. Together, our findings indicate that the plasticity of an adult somatic organ is reversibly controlled by its sexual identity, imparted by a new mechanism that may be active in more tissues than previously recognised. PMID:26887495

  20. SCF/c-kit signaling is required in 12-O-tetradecanoylphorbol-13-acetate-induced migration and differentiation of hair follicle melanocytes for epidermal pigmentation.

    PubMed

    Qiu, Weiming; Yang, Ke; Lei, Mingxing; Yan, Hongtao; Tang, Hui; Bai, Xiufeng; Yang, Guihong; Lian, Xiaohua; Wu, Jinjin

    2015-05-01

    Hair follicle melanocyte stem cells (McSCs) are responsible for hair pigmentation and also function as a major melanocyte reservoir for epidermal pigmentation. However, the molecular mechanism promoting McSCs for epidermal pigmentation remains elusive. 12-O-tetradecanoylphorbol-13-acetate (TPA) mimics key signaling involved in melanocyte growth, migration and differentiation. We therefore investigated the molecular basis for the contribution of hair follicle McSCs to epidermal pigmentation using the TPA induction model. We found that repetitive TPA treatment of female C57BL/6 mouse dorsal skin induced epidermal pigmentation by increasing the number of epidermal melanocytes. Particularly, TPA treatment induced McSCs to initiate proliferation, exit the stem cell niche and differentiate. We also demonstrated that TPA promotes melanoblast migration and differentiation in vitro. At the molecular level, TPA treatment induced robust expression of stem cell factor (SCF) in keratinocytes and c-kit in melanoblasts and melanocytes. Administration of ACK2, a neutralizing antibody against the Kit receptor, suppressed mouse epidermal pigmentation, decreased the number of epidermal melanocytes, and inhibited melanoblast migration. Taken together, our data demonstrate that TPA promotes the expansion, migration and differentiation of hair follicle McSCs for mouse epidermal pigmentation. SCF/c-kit signaling was required for TPA-induced migration and differentiation of hair follicle melanocytes. Our findings may provide an excellent model to investigate the signaling mechanisms regulating epidermal pigmentation from mouse hair follicle McSCs, and a potential therapeutic option for skin pigmentation disorders.

  1. Myf5 haploinsufficiency reveals distinct cell fate potentials for adult skeletal muscle stem cells.

    PubMed

    Gayraud-Morel, Barbara; Chrétien, Fabrice; Jory, Aurélie; Sambasivan, Ramkumar; Negroni, Elisa; Flamant, Patricia; Soubigou, Guillaume; Coppée, Jean-Yves; Di Santo, James; Cumano, Ana; Mouly, Vincent; Tajbakhsh, Shahragim

    2012-04-01

    Skeletal muscle stem cell fate in adult mice is regulated by crucial transcription factors, including the determination genes Myf5 and Myod. The precise role of Myf5 in regulating quiescent muscle stem cells has remained elusive. Here we show that most, but not all, quiescent satellite cells express Myf5 protein, but at varying levels, and that resident Myf5 heterozygous muscle stem cells are more primed for myogenic commitment compared with wild-type satellite cells. Paradoxically however, heterotypic transplantation of Myf5 heterozygous cells into regenerating muscles results in higher self-renewal capacity compared with wild-type stem cells, whereas myofibre regenerative capacity is not altered. By contrast, Pax7 haploinsufficiency does not show major modifications by transcriptome analysis. These observations provide a mechanism linking Myf5 levels to muscle stem cell heterogeneity and fate by exposing two distinct and opposing phenotypes associated with Myf5 haploinsufficiency. These findings have important implications for how stem cell fates can be modulated by crucial transcription factors while generating a pool of responsive heterogeneous cells.

  2. Identifying endogenous neural stem cells in the adult brain in vitro and in vivo: novel approaches.

    PubMed

    Rueger, Maria Adele; Androutsellis-Theotokis, Andreas

    2013-01-01

    In the 1960s, Joseph Altman reported that the adult mammalian brain is capable of generating new neurons. Today it is understood that some of these neurons are derived from uncommitted cells in the subventricular zone lining the lateral ventricles, and the dentate gyrus of the hippocampus. The first area generates new neuroblasts which migrate to the olfactory bulb, whereas hippocampal neurogenesis seems to play roles in particular types of learning and memory. A part of these uncommitted (immature) cells is able to divide and their progeny can generate all three major cell types of the nervous system: neurons, astrocytes, and oligodendrocytes; these properties define such cells as neural stem cells. Although the roles of these cells are not yet clear, it is accepted that they affect functions including olfaction and learning/memory. Experiments with insults to the central nervous system also show that neural stem cells are quickly mobilized due to injury and in various disorders by proliferating, and migrating to injury sites. This suggests a role of endogenous neural stem cells in disease. New pools of stem cells are being discovered, suggesting an even more important role for these cells. To understand these cells and to coax them to contribute to tissue repair it would be very useful to be able to image them in the living organism. Here we discuss advances in imaging approaches as well as new concepts that emerge from stem cell biology with emphasis on the interface between imaging and stem cells.

  3. Topology of feather melanocyte progenitor niche allows complex pigment patterns to emerge.

    PubMed

    Lin, S J; Foley, J; Jiang, T X; Yeh, C Y; Wu, P; Foley, A; Yen, C M; Huang, Y C; Cheng, H C; Chen, C F; Reeder, B; Jee, S H; Widelitz, R B; Chuong, C M

    2013-06-21

    Color patterns of bird plumage affect animal behavior and speciation. Diverse patterns are present in different species and within the individual. Here, we study the cellular and molecular basis of feather pigment pattern formation. Melanocyte progenitors are distributed as a horizontal ring in the proximal follicle, sending melanocytes vertically up into the epithelial cylinder, which gradually emerges as feathers grow. Different pigment patterns form by modulating the presence, arrangement, or differentiation of melanocytes. A layer of peripheral pulp further regulates pigmentation via patterned agouti expression. Lifetime feather cyclic regeneration resets pigment patterns for physiological needs. Thus, the evolution of stem cell niche topology allows complex pigment patterning through combinatorial co-option of simple regulatory mechanisms.

  4. Adult Adipose-Derived Stem Cell Attachment to Biomaterials

    PubMed Central

    Prichard, Heather L; Reichert, William M; Klitzman, Bruce

    2007-01-01

    Attachment of adipose-derived stem cells (ASC) to biomaterials prior to implantation is a possible strategy for mediating inflammation and wound healing. In this study, the ASC percent coverage was measured on common medical grade biosensor materials subjected to different surface treatments. Cell coverage on silicone elastomer (poly dimethylsiloxane) was below 20% for all surface treatments. Polyimide (Kapton), polyurethane (Pellethane) and tissue culture polystyrene all exhibited >50% coverage for surfaces treated with fibronectin (Fn), fibronectin plus avidin/biotin (dual ligand), and oxygen plasma plus fibronectin treatments (Fn O2). The fibronectin treatment performed as well or better on polyimide, polyurethane, and tissue culture polystyrene compared to the dual ligand and fibronectin oxygen plasma treated surfaces. Cell detachment with increasing shear stresses was <25% for each attachment method on both polyimide and polyurethane. The effects of attachment methods on the basic cell functions of proliferation, metabolism, ATP concentration, and caspase-3 activity were analyzed yielding proliferation profiles that were very similar among all of the materials. No significant differences in metabolism, intracellular ATP, or intracellular caspase-3 activity were observed for any of the attachment methods on either polyimide or polyurethane. PMID:17074385

  5. A reverse transfection technology to genetically engineer adult stem cells.

    PubMed

    Okazaki, Arimichi; Jo, Jun-Ichiro; Tabata, Yasuhiko

    2007-02-01

    A new non-viral method of gene transfection was designed to enhance the level of gene expression for rat mesenchymal stem cells (MSCs). Pullulan was cationized using chemical introduction of spermine to prepare cationized pullulan of non-viral carrier (spermine-pullulan). The spermine-pullulan was complexed with a plasmid deoxyribonucleic acid (DNA) of luciferase and coated on the surface of culture substrate together with Pronectin of artificial cell adhesion protein. MSCs were cultured and transfected on the complex-coated substrate (reverse transfection), and the level and duration of gene expression were compared with those of MSCs transfected by culturing in the medium containing the plasmid DNA-spermine-pullulan complex (conventional method). The reverse transfection method enhanced and prolonged gene expression significantly more than did the conventional method. The reverse method permitted the transfection culture of MSCs in the presence of serum, in contrast to the conventional method, which gave cells a good culture condition to lower cytotoxicity. The reverse transfection was carried out for a non-woven fabric of polyethylene terephthalate (PET) coated with the complex and Pronectin using agitation and stirring culture methods. The two methods enhanced the level and duration of gene expression for MSCs significantly more than did the static method. It is possible that medium circulation improves the culture conditions of cells in terms of oxygen and nutrition supply and waste excretion, resulting in enhanced gene expression.

  6. Repression of genes involved in melanocyte differentiation in uveal melanoma

    PubMed Central

    Bergeron, Marjorie-Allison; Champagne, Sophie; Gaudreault, Manon; Deschambeault, Alexandre

    2012-01-01

    Purpose Uveal melanoma (UM) has been the subject of intense interest due to its distinctive metastatic pattern, which involves hematogenous dissemination of cancerous cells toward the liver in 50% of patients. To search for new UM prognostic markers, the Suppressive Subtractive Hybridization (SSH) technique was used to isolate genes that are differentially expressed between UM primary tumors and normal uveal melanocytes (UVM). Methods A subtracted cDNA library was prepared using cDNA from uncultured UM primary tumors and UVM. The expression level of selected genes was further validated by cDNA microarray, semi-quantitative reverse transcription polymerase chain reaction (RT-PCR), and immunofluorescence analyses. Results One hundred-fifteen genes were identified using the SSH technique. Microarray analyses comparing the gene expression profiles of UM primary tumors to UVM validated a significant differential expression for 48% of these genes. The expression pattern of selected genes was then analyzed by semi-quantitative RT–PCR and was found to be consistent with the SSH and cDNA microarray findings. A down-regulation of genes associated with melanocyte differentiation was confirmed in UM primary tumors. Presence of undifferentiated cells in the UM was demonstrated by the expression of stem cell markers ATP-binding cassette sub-family G member 2 (ABCG2) and octamer-binding protein 4 (OCT4). Conclusions We demonstrated that the SSH technique is efficient to detect differentially expressed genes between UM and UVM. The genes identified in this study represent valuable candidates for further functional analysis in UM and should be informative in studying the biology of this tumor. In addition, deregulation of the melanocyte differentiation pathway revealed the presence of UM cells exhibiting a stem cell-like phenotype. PMID:22815634

  7. Effects of addictive drugs on adult neural stem/progenitor cells

    PubMed Central

    Xu, Chi; Loh, Horace H.; Law, Ping-Yee

    2015-01-01

    Neural stem/progenitor cells (NSPCs) undergo a series of developmental processes before giving rise to newborn neurons, astrocytes and oligodendrocytes in adult neurogenesis. During the past decade, the role of NSPCs has been highlighted by studies on adult neurogenesis modulated by addictive drugs. It has been proven that these drugs regulate the proliferation, differentiation and survival of adult NSPCs in different manners, which results in the varying consequences of adult neurogenesis. The effects of addictive drugs on NSPCs are exerted via a variety of different mechanisms and pathways, which interact with one another and contribute to the complexity of NSPC regulation. Here, we review the effects of different addictive drugs on NSPCs, and the related experimental methods and paradigms. We also discuss the current understanding of major signaling molecules, especially the putative common mechanisms, underlying such effects. Finally, we review the future directions of research in this area. PMID:26468052

  8. Mobilized adult pituitary stem cells contribute to endocrine regeneration in response to physiological demand.

    PubMed

    Rizzoti, Karine; Akiyama, Haruhiko; Lovell-Badge, Robin

    2013-10-03

    Pituitary hormone deficiencies, with Growth Hormone deficiency being most frequent (1 in 3,500-10,000 births), cause significant morbidity. Regeneration of missing endocrine cells would be a significant improvement over hormone replacement therapies, which incur side effects and do not mimic physiological secretion patterns. Recent in vitro studies have identified a population of adult pituitary progenitors that express the HMG box transcription factors SOX2 and SOX9. Here, we apply cell-lineage tracing analysis to demonstrate that SOX2- and SOX9-expressing progenitors can self-renew and give rise to endocrine cells in vivo, suggesting that they are tissue stem cells. Moreover, we show that they can become mobilized and differentiate into the appropriate endocrine cell types in response to physiological stress. Our results highlight the pituitary as a model for exploring how physiological changes influence stem cell behavior and suggest that manipulation of endogenous pituitary stem cells is a potential therapeutic strategy for pituitary deficiencies.

  9. Muscle regeneration by adipose tissue-derived adult stem cells attached to injectable PLGA spheres.

    PubMed

    Kim, MiJung; Choi, Yu Suk; Yang, Seung Hye; Hong, Hea-Nam; Cho, Sung-Woo; Cha, Sang Myun; Pak, Jhang Ho; Kim, Chan Wha; Kwon, Seog Woon; Park, Chan Jeoung

    2006-09-22

    The [corrected] use of adult stem cells for cell-based tissue engineering and regeneration strategies represents a promising approach for skeletal muscle repair. We have evaluated the combination of adipose tissue-derived adult stem cells (ADSCs) obtained from autologous liposuction and injectable poly(lactic-co-glycolic acid) (PLGA) spheres for muscle regeneration. ADSCs attached to PLGA spheres and PLGA spheres alone were cultured in myogenic medium for 21 days and injected subcutaneously into the necks of nude mice. After 30 and 60 days, the mice were sacrificed, and newly formed tissues were analyzed by immunostaining, H and E staining, and RT-PCR. We found that ADSCs attached to PLGA spheres, but not PLGA spheres alone, were able to generate muscle tissue. These findings suggest that ADSCs and PLGA spheres are useful materials for muscle tissue engineering and that their combination can be used in clinical settings for muscle regeneration.

  10. The Par complex and integrins direct asymmetric cell division in adult intestinal stem cells.

    PubMed

    Goulas, Spyros; Conder, Ryan; Knoblich, Juergen A

    2012-10-05

    The adult Drosophila midgut is maintained by intestinal stem cells (ISCs) that generate both self-renewing and differentiating daughter cells. How this asymmetry is generated is currently unclear. Here, we demonstrate that asymmetric ISC division is established by a unique combination of extracellular and intracellular polarity mechanisms. We show that Integrin-dependent adhesion to the basement membrane induces cell-intrinsic polarity and results in the asymmetric segregation of the Par proteins Par-3, Par-6, and aPKC into the apical daughter cell. Cell-specific knockdown and overexpression experiments suggest that increased activity of aPKC enhances Delta/Notch signaling in one of the two daughter cells to induce terminal differentiation. Perturbing this mechanism or altering the orientation of ISC division results in the formation of intestinal tumors. Our data indicate that mechanisms for intrinsically asymmetric cell division can be adapted to allow for the flexibility in lineage decisions that is required in adult stem cells.

  11. Embryonic origin of adult stem cells required for tissue homeostasis and regeneration.

    PubMed

    Davies, Erin L; Lei, Kai; Seidel, Christopher W; Kroesen, Amanda E; McKinney, Sean A; Guo, Longhua; Robb, Sofia Mc; Ross, Eric J; Gotting, Kirsten; Alvarado, Alejandro Sánchez

    2017-01-10

    Planarian neoblasts are pluripotent, adult somatic stem cells and lineage-primed progenitors that are required for the production and maintenance of all differentiated cell types, including the germline. Neoblasts, originally defined as undifferentiated cells residing in the adult parenchyma, are frequently compared to embryonic stem cells yet their developmental origin remains obscure. We investigated the provenance of neoblasts during Schmidtea mediterranea embryogenesis, and report that neoblasts arise from an anarchic, cycling piwi-1+ population wholly responsible for production of all temporary and definitive organs during embryogenesis. Early embryonic piwi-1+ cells are molecularly and functionally distinct from neoblasts: they express unique cohorts of early embryo enriched transcripts and behave differently than neoblasts in cell transplantation assays. Neoblast lineages arise as organogenesis begins and are required for construction of all major organ systems during embryogenesis. These subpopulations are continuously generated during adulthood, where they act as agents of tissue homeostasis and regeneration.

  12. Organoids from adult liver and pancreas: Stem cell biology and biomedical utility.

    PubMed

    Hindley, Christopher J; Cordero-Espinoza, Lucía; Huch, Meritxell

    2016-12-15

    The liver and pancreas are critical organs maintaining whole body metabolism. Historically, the expansion of adult-derived cells from these organs in vitro has proven challenging and this in turn has hampered studies of liver and pancreas stem cell biology, as well as being a roadblock to disease modelling and cell replacement therapies for pathologies in these organs. Recently, defined culture conditions have been described which allow the in vitro culture and manipulation of adult-derived liver and pancreatic material. Here we review these systems and assess their physiological relevance, as well as their potential utility in biomedicine.

  13. Notch signaling induces retinal stem-like properties in perinatal neural retina progenitors and promotes symmetric divisions in adult retinal stem cells.

    PubMed

    Balenci, Laurent; van der Kooy, Derek

    2014-02-01

    Understanding the mechanisms regulating retinal stem cell (RSC) activity is fundamental for future stem cell-based therapeutic purposes. By combining gain and loss of function approaches, we addressed whether Notch signaling may play a selective role in retinal stem versus retinal progenitor cells in both developing and adult eyes. Inhibition of either Notch or fibroblast growth factor signaling reduced proliferation of retinal stem and retinal progenitor cells, and inhibited RSC self-renewal. Conversely, exogenous Delta-like 3 and direct intrinsic Notch activation stimulated expansionary symmetric divisions in adult RSCs with the concomitant upregulation of Hes5. Knocking down Hes5 expression specifically decreased the numbers, but not the diameters, of adult RSC primary spheres, indicating that HES5 is the downstream effector of Notch receptor in controlling adult RSC proliferation. In addition, constitutive Notch activation induced retinal stem-like asymmetric self-renewal properties, with no expansion (no symmetrical division) in perinatal neural retina progenitor cells. These findings highlight central roles of Notch signaling activity in regulating the modes of division of retinal stem and retinal progenitor cells.

  14. Comparative transcriptome analysis of embryonic and adult stem cells with extended and limited differentiation capacity

    PubMed Central

    Ulloa-Montoya, Fernando; Kidder, Benjamin L; Pauwelyn, Karen A; Chase, Lucas G; Luttun, Aernout; Crabbe, Annelies; Geraerts, Martine; Sharov, Alexei A; Piao, Yulan; Ko, Minoru SH; Hu, Wei-Shou; Verfaillie, Catherine M

    2007-01-01

    Background Recently, several populations of postnatal stem cells, such as multipotent adult progenitor cells (MAPCs), have been described that have broader differentiation ability than classical adult stem cells. Here we compare the transcriptome of pluripotent embryonic stem cells (ESCs), MAPCs, and lineage-restricted mesenchymal stem cells (MSCs) to determine their relationship. Results Applying principal component analysis, non-negative matrix factorization and k-means clustering algorithms to the gene-expression data, we identified a unique gene-expression profile for MAPCs. Apart from the ESC-specific transcription factor Oct4 and other ESC transcripts, some of them associated with maintaining ESC pluripotency, MAPCs also express transcripts characteristic of early endoderm and mesoderm. MAPCs do not, however, express Nanog or Sox2, two other key transcription factors involved in maintaining ESC properties. This unique molecular signature was seen irrespective of the microarray platform used and was very similar for both mouse and rat MAPCs. As MSC-like cells isolated under MAPC conditions are virtually identical to MSCs, and MSCs cultured in MAPC conditions do not upregulate MAPC-expressed transcripts, the MAPC signature is cell-type specific and not merely the result of differing culture conditions. Conclusion Multivariate analysis techniques clustered stem cells on the basis of their expressed gene profile, and the genes determining this clustering reflected the stem cells' differentiation potential in vitro. This comparative transcriptome analysis should significantly aid the isolation and culture of MAPCs and MAPC-like cells, and form the basis for studies to gain insights into genes that confer on these cells their greater developmental potency. PMID:17683608

  15. Isolation, culture, and transfection of melanocytes.

    PubMed

    Godwin, Lauren S; Castle, Joanna T; Kohli, Jaskaren S; Goff, Philip S; Cairney, Claire J; Keith, W Nicol; Sviderskaya, Elena V; Bennett, Dorothy C

    2014-06-03

    Located in the basal epidermis and hair follicles, melanocytes of the integument are responsible for its coloration through production of melanin pigments. Melanin is produced in lysosomal-like organelles called melanosomes. In humans, this skin pigmentation acts as an ultraviolet radiation filter. Abnormalities in the division of melanocytes are quite common, with potentially oncogenic growth usually followed by cell senescence producing benign naevi (moles), or occasionally melanoma. Therefore, melanocytes are a useful model for studying melanoma, as well as pigmentation and organelle transport and the diseases affecting these mechanisms. This chapter focuses on the isolation, culture, and transfection of human and murine melanocytes. The first basic protocol describes the primary culture of melanocytes from human skin and the maintenance of growing cultures. The second basic protocol details the subculture and preparation of mouse keratinocyte feeder cells. The primary culture of melanocytes from mouse skin is described in the third basic protocol, and, lastly, the fourth basic protocol outlines a technique for transfecting melanocytes and melanoma cells.

  16. Adult marrow-derived very small embryonic-like stem cells and tissue engineering.

    PubMed

    Kucia, Magda; Zuba-Surma, Ewa K; Wysoczynski, Marcin; Wu, Wan; Ratajczak, Janina; Machalinski, Boguslaw; Ratajczak, Mariusz Z

    2007-10-01

    A population of CXCR4(+) lin(-) CD45(-) cells that express SSEA, Oct-4 and Nanog has been identified in adult bone marrow. These cells are very small and display several features typical for primary embryonic stem cells such as: i) a large nuclei surrounded by a narrow rim of cytoplasm; ii) open-type chromatin (euchromatin); and iii) high telomerase activity. These cells were named very small embryonic-like stem cells (VSEL-SC). The authors hypothesized that they are direct descendants of the germ lineage. Germ lineage, in order to pass genes on to the next generation, has to create soma and thus becomes a 'mother lineage' for all somatic cell lineages present in the adult body. Germ potential is established after conception in a totipotent zygote and retained subsequently during development in blastomers of morula, cells form the inner cell mass of blastocyst, epiblast and population of primordial germ cells. The authors envision that VSEL-SC are epiblast-derived pluripotent stem cells and could potentially become a less-controversial source of stem cells for regeneration.

  17. Spontaneous transformation of adult mesenchymal stem cells from cynomolgus macaques in vitro

    SciTech Connect

    Ren, Zhenhua; Wang, Jiayin; Zhu, Wanwan; Guan, Yunqian; Zou, Chunlin; Chen, Zhiguo; Zhang, Y. Alex

    2011-12-10

    Mesenchymal stem cells (MSCs) have shown potential clinical utility in cell therapy and tissue engineering, due to their ability to proliferate as well as to differentiate into multiple lineages, including osteogenic, adipogenic, and chondrogenic specifications. Therefore, it is crucial to assess the safety of MSCs while extensive expansion ex vivo is a prerequisite to obtain the cell numbers for cell transplantation. Here we show that MSCs derived from adult cynomolgus monkey can undergo spontaneous transformation following in vitro culture. In comparison with MSCs, the spontaneously transformed mesenchymal cells (TMCs) display significantly different growth pattern and morphology, reminiscent of the characteristics of tumor cells. Importantly, TMCs are highly tumorigenic, causing subcutaneous tumors when injected into NOD/SCID mice. Moreover, no multiple differentiation potential of TMCs is observed in vitro or in vivo, suggesting that spontaneously transformed adult stem cells may not necessarily turn into cancer stem cells. These data indicate a direct transformation of cynomolgus monkey MSCs into tumor cells following long-term expansion in vitro. The spontaneous transformation of the cultured cynomolgus monkey MSCs may have important implications for ongoing clinical trials and for models of oncogenesis, thus warranting a more strict assessment of MSCs prior to cell therapy. -- Highlights: Black-Right-Pointing-Pointer Spontaneous transformation of cynomolgus monkey MSCs in vitro. Black-Right-Pointing-Pointer Transformed mesenchymal cells lack multipotency. Black-Right-Pointing-Pointer Transformed mesenchymal cells are highly tumorigenic. Black-Right-Pointing-Pointer Transformed mesenchymal cells do not have the characteristics of cancer stem cells.

  18. Autologous Transplantation of Bone Marrow Adult Stem Cells for the Treatment of Idiopathic Dilated Cardiomyopathy

    PubMed Central

    Westphal, Ricardo João; Bueno, Ronaldo Rocha Loures; Galvão, Paulo Bezerra de Araújo; Zanis Neto, José; Souza, Juliano Mendes; Guérios, Ênio Eduardo; Senegaglia, Alexandra Cristina; Brofman, Paulo Roberto; Pasquini, Ricardo; da Cunha, Claudio Leinig Pereira

    2014-01-01

    Background Morbimortality in patients with dilated idiopathic cardiomyopathy is high, even under optimal medical treatment. Autologous infusion of bone marrow adult stem cells has shown promising preliminary results in these patients. Objective Determine the effectiveness of autologous transplantation of bone marrow adult stem cells on systolic and diastolic left ventricular function, and on the degree of mitral regurgitation in patients with dilated idiopathic cardiomyopathy in functional classes NYHA II and III. Methods We administered 4,54 x 108 ± 0,89 x 108 bone marrow adult stem cells into the coronary arteries of 24 patients with dilated idiopathic cardiomyopathy in functional classes NYHA II and III. Changes in functional class, systolic and diastolic left ventricular function and degree of mitral regurgitation were assessed after 3 months, 6 months and 1 year. Results During follow-up, six patients (25%) improved functional class and eight (33.3%) kept stable. Left ventricular ejection fraction improved 8.9%, 9.7% e 13.6%, after 3, 6 and 12 months (p = 0.024; 0.017 and 0.018), respectively. There were no significant changes neither in diastolic left ventricular function nor in mitral regurgitation degree. A combined cardiac resynchronization and implantable cardioversion defibrillation was implanted in two patients (8.3%). Four patients (16.6%) had sudden death and four patients died due to terminal cardiac failure. Average survival of these eight patients was 2.6 years. Conclusion Intracoronary infusion of bone marrow adult stem cells was associated with an improvement or stabilization of functional class and an improvement in left ventricular ejection fraction, suggesting the efficacy of this intervention. There were no significant changes neither in left ventricular diastolic function nor in the degree of mitral regurgitation. PMID:25590932

  19. A Hyaluronic Acid-Rich Node and Duct System in Which Pluripotent Adult Stem Cells Circulate.

    PubMed

    Rai, Rajani; Chandra, Vishal; Kwon, Byoung S

    2015-10-01

    Regenerative medicine is in demand of adult pluripotent stem cells (PSCs). The "Bonghan System (BHS)" was discovered and suggested to contain cells with regenerative capacity in the early 1960s. It had been ignored for a long time due to the lack of sufficient details of experiments, but about 37 years after the initial report, the BHS was rediscovered and named as the "primo vascular system." Recently, we have discovered a similar structure, which contained a high level of hyaluronic acid, and hence, named the structure as hyaluronic acid-rich node and duct system (HAR-NDS). Here we discuss the HAR-NDS concept starting from the discovery of BHS, and findings pointing to its importance in regenerative medicine. This HAR-NDS contained adult PSCs, called node and duct stem cells (NDSCs), which appeared to circulate in it. We describe the evidence that NDSCs can differentiate into hemangioblasts that further produced differentiated blood cells. The NDSCs had a potential to differentiate into neuronal cells and hepatocytes; thus, NDSCs had a capability to become cells from all three germ layers. This system appears to be a promising alternative source of adult stem cells that can be easily delivered to their target tissues and participate in tissue regeneration.

  20. Regulatory System for Stem/Progenitor Cell Niches in the Adult Rodent Pituitary

    PubMed Central

    Yoshida, Saishu; Kato, Takako; Kato, Yukio

    2016-01-01

    The anterior lobe of the pituitary gland is a master endocrine tissue composed of five types of endocrine cells. Although the turnover rate of pituitary endocrine cells is as low as about 1.6% per day, recent studies have demonstrated that Sex-determining region Y-box 2 (SOX2)+-cells exist as pituitary stem/progenitor cells in the adult anterior lobe and contribute to cell regeneration. Notably, SOX2+-pituitary stem/progenitor cells form two types of niches in this tissue: the marginal cell layer (MCL-niche) and the dense cell clusters scattering in the parenchyma (parenchymal-niche). However, little is known about the mechanisms and factors for regulating the pituitary stem/progenitor cell niches, as well as the functional differences between the two types of niches. Elucidation of the regulatory mechanisms in the niches might enable us to understand the cell regeneration system that acts in accordance with physiological demands in the adult pituitary. In this review, so as to reveal the regulatory mechanisms of the two types of niche, we summarize the regulatory factors and their roles in the adult rodent pituitary niches by focusing on three components: soluble factors, cell surface proteins and extracellular matrixes. PMID:26761002

  1. Adult neurogenesis, neural stem cells and Alzheimer's disease: developments, limitations, problems and promises.

    PubMed

    Taupin, Philippe

    2009-12-01

    Alzheimer's disease (AD) is an irreversible progressive neurodegenerative disease, leading to severe incapacity and death. It is the most common form of dementia among older people. AD is characterized in the brain by amyloid plaques, neurofibrillary tangles, neuronal degeneration, aneuploidy and enhanced neurogenesis and by cognitive, behavioral and physical impairments. Inherited mutations in several genes and genetic, acquired and environmental risk factors have been reported as causes for developing the disease, for which there is currently no cure. Current treatments for AD involve drugs and occupational therapies, and future developments involve early diagnosis and stem cell therapy. In this manuscript, we will review and discuss the recent developments, limitations, problems and promises on AD, particularly related to aneuploidy, adult neurogenesis, neural stem cells (NSCs) and cellular therapy. Though adult neurogenesis may be beneficial for regeneration of the nervous system, it may underly the pathogenesis of AD. Cellular therapy is a promising strategy for AD. Limitations in protocols to establish homogeneous populations of neural progenitor and stem cells and niches for neurogenesis need to be resolved and unlocked, for the full potential of adult NSCs to be realized for therapy.

  2. Lymphatic Reprogramming of Adult Endothelial Stem Cells for a Cell-Based Therapy for Lymphedema in Breast Cancer Patients

    DTIC Science & Technology

    2008-09-01

    Therapy for Lymphedema inBreast Cancer Patients PRINCIPAL INVESTIGATOR: Young Kwon Hong, Ph.D. CONTRACTING ORGANIZATION...5a. CONTRACT NUMBER 4. TITLE AND SUBTITLE Lymphatic Reprogramming of Adult Endothelial Stem Cells for a Cell-Based Therapy for Lymphedema in... lymphedema patients. The key significance of our proposal is to utilize the elusive circulating adult stem cells to avoid the ethical and immunological

  3. Pituitary Cell Turnover: From Adult Stem Cell Recruitment through Differentiation to Death.

    PubMed

    Garcia-Lavandeira, Montserrat; Diaz-Rodriguez, Esther; Bahar, Dilek; Garcia-Rendueles, Angela R; Rodrigues, Joana S; Dieguez, Carlos; Alvarez, Clara V

    2015-01-01

    The recent demonstration using genetic tracing that in the adult pituitary stem cells are normally recruited from the niche in the marginal zone and differentiate into secretory cells in the adenopituitary has elegantly confirmed the proposal made when the pituitary stem cell niche was first discovered 5 years ago. Some of the early controversies have also been resolved. However, many questions remain, such as which are the markers that make a pituitary stem cell truly unique and the exact mechanisms that trigger recruitment from the niche. Little is known about the processes of commitment and differentiation once a stem cell has left the niche. Moreover, the acceptance that pituitary cells are renewed by stem cells implies the existence of regulated mechanisms of cell death in differentiated cells which must themselves be explained. The demonstration of an apoptotic pathway mediated by RET/caspase 3/Pit-1/Arf/p53 in normal somatotrophs is therefore an important step towards understanding how pituitary cell number is regulated. Further work will elucidate how the rates of the three processes of cell renewal, differentiation and apoptosis are balanced in tissue homeostasis after birth, but altered in pituitary hyperplasia in response to physiological stimuli such as puberty and lactation. Thus, we can aim to understand the mechanisms underlying human disease due to insufficient (hypopituitarism) or excess (pituitary tumor) cell numbers.

  4. Potential for a pluripotent adult stem cell treatment for acute radiation sickness

    PubMed Central

    Rodgerson, Denis O; Reidenberg, Bruce E; Harris, Alan G; Pecora, Andrew L

    2012-01-01

    Accidental radiation exposure and the threat of deliberate radiation exposure have been in the news and are a public health concern. Experience with acute radiation sickness has been gathered from atomic blast survivors of Hiroshima and Nagasaki and from civilian nuclear accidents as well as experience gained during the development of radiation therapy for cancer. This paper reviews the medical treatment reports relevant to acute radiation sickness among the survivors of atomic weapons at Hiroshima and Nagasaki, among the victims of Chernobyl, and the two cases described so far from the Fukushima Dai-Ichi disaster. The data supporting the use of hematopoietic stem cell transplantation and the new efforts to expand stem cell populations ex vivo for infusion to treat bone marrow failure are reviewed. Hematopoietic stem cells derived from bone marrow or blood have a broad ability to repair and replace radiation induced damaged blood and immune cell production and may promote blood vessel formation and tissue repair. Additionally, a constituent of bone marrow-derived, adult pluripotent stem cells, very small embryonic like stem cells, are highly resistant to ionizing radiation and appear capable of regenerating radiation damaged tissue including skin, gut and lung. PMID:24520532

  5. Loss of DNA mismatch repair imparts a selective advantage in planarian adult stem cells.

    PubMed

    Hollenbach, Jessica P; Resch, Alissa M; Palakodeti, Dasaradhi; Graveley, Brenton R; Heinen, Christopher D

    2011-01-01

    Lynch syndrome (LS) leads to an increased risk of early-onset colorectal and other types of cancer and is caused by germline mutations in DNA mismatch repair (MMR) genes. Loss of MMR function results in a mutator phenotype that likely underlies its role in tumorigenesis. However, loss of MMR also results in the elimination of a DNA damage-induced checkpoint/apoptosis activation barrier that may allow damaged cells to grow unchecked. A fundamental question is whether loss of MMR provides pre-cancerous stem cells an immediate selective advantage in addition to establishing a mutator phenotype. To test this hypothesis in an in vivo system, we utilized the planarian Schmidtea mediterranea which contains a significant population of identifiable adult stem cells. We identified a planarian homolog of human MSH2, a MMR gene which is mutated in 38% of LS cases. The planarian Smed-msh2 is expressed in stem cells and some progeny. We depleted Smed-msh2 mRNA levels by RNA-interference and found a striking survival advantage in these animals treated with a cytotoxic DNA alkylating agent compared to control animals. We demonstrated that this tolerance to DNA damage is due to the survival of mitotically active, MMR-deficient stem cells. Our results suggest that loss of MMR provides an in vivo survival advantage to the stem cell population in the presence of DNA damage that may have implications for tumorigenesis.

  6. The lipolysis pathway sustains normal and transformed stem cells in adult Drosophila.

    PubMed

    Singh, Shree Ram; Zeng, Xiankun; Zhao, Jiangsha; Liu, Ying; Hou, Gerald; Liu, Hanhan; Hou, Steven X

    2016-10-06

    Cancer stem cells (CSCs) may be responsible for tumour dormancy, relapse and the eventual death of most cancer patients. In addition, these cells are usually resistant to cytotoxic conditions. However, very little is known about the biology behind this resistance to therapeutics. Here we investigated stem-cell death in the digestive system of adult Drosophila melanogaster. We found that knockdown of the coat protein complex I (COPI)-Arf79F (also known as Arf1) complex selectively killed normal and transformed stem cells through necrosis, by attenuating the lipolysis pathway, but spared differentiated cells. The dying stem cells were engulfed by neighbouring differentiated cells through a draper-myoblast city-Rac1-basket (also known as JNK)-dependent autophagy pathway. Furthermore, Arf1 inhibitors reduced CSCs in human cancer cell lines. Thus, normal or cancer stem cells may rely primarily on lipid reserves for energy, in such a way that blocking lipolysis starves them to death. This finding may lead to new therapies that could help to eliminate CSCs in human cancers.

  7. A subpopulation of adult skeletal muscle stem cells retains all template DNA strands after cell division.

    PubMed

    Rocheteau, Pierre; Gayraud-Morel, Barbara; Siegl-Cachedenier, Irene; Blasco, Maria A; Tajbakhsh, Shahragim

    2012-01-20

    Satellite cells are adult skeletal muscle stem cells that are quiescent and constitute a poorly defined heterogeneous population. Using transgenic Tg:Pax7-nGFP mice, we show that Pax7-nGFP(Hi) cells are less primed for commitment and have a lower metabolic status and delayed first mitosis compared to Pax7-nGFP(Lo) cells. Pax7-nGFP(Hi) can give rise to Pax7-nGFP(Lo) cells after serial transplantations. Proliferating Pax7-nGFP(Hi) cells exhibit lower metabolic activity, and the majority performs asymmetric DNA segregation during cell division, wherein daughter cells retaining template DNA strands express stem cell markers. Using chromosome orientation-fluorescence in situ hybridization, we demonstrate that all chromatids segregate asymmetrically, whereas Pax7-nGFP(Lo) cells perform random DNA segregation. Therefore, quiescent Pax7-nGFP(Hi) cells represent a reversible dormant stem cell state, and during muscle regeneration, Pax7-nGFP(Hi) cells generate distinct daughter cell fates by asymmetrically segregating template DNA strands to the stem cell. These findings provide major insights into the biology of stem cells that segregate DNA asymmetrically.

  8. Ependymal cells of chordate larvae are stem-like cells that form the adult nervous system.

    PubMed

    Horie, Takeo; Shinki, Ryoko; Ogura, Yosuke; Kusakabe, Takehiro G; Satoh, Nori; Sasakura, Yasunori

    2011-01-27

    In ascidian tunicates, the metamorphic transition from larva to adult is accompanied by dynamic changes in the body plan. For instance, the central nervous system (CNS) is subjected to extensive rearrangement because its regulating larval organs are lost and new adult organs are created. To understand how the adult CNS is reconstructed, we traced the fate of larval CNS cells during ascidian metamorphosis by using transgenic animals and imaging technologies with photoconvertible fluorescent proteins. Here we show that most parts of the ascidian larval CNS, except for the tail nerve cord, are maintained during metamorphosis and recruited to form the adult CNS. We also show that most of the larval neurons disappear and only a subset of cholinergic motor neurons and glutamatergic neurons are retained. Finally, we demonstrate that ependymal cells of the larval CNS contribute to the construction of the adult CNS and that some differentiate into neurons in the adult CNS. An unexpected role of ependymal cells highlighted by this study is that they serve as neural stem-like cells to reconstruct the adult nervous network during chordate metamorphosis. Consequently, the plasticity of non-neuronal ependymal cells and neuronal cells in chordates should be re-examined by future studies.

  9. Adult neural stem cells: Long-term self-renewal, replenishment by the immune system, or both?

    PubMed

    Beltz, Barbara S; Cockey, Emily L; Li, Jingjing; Platto, Jody F; Ramos, Kristina A; Benton, Jeanne L

    2015-05-01

    The current model of adult neurogenesis in mammals suggests that adult-born neurons are generated by stem cells that undergo long-term self-renewal, and that a lifetime supply of stem cells resides in the brain. In contrast, it has recently been demonstrated that adult-born neurons in crayfish are generated by precursors originating in the immune system. This is particularly interesting because studies done many years ago suggest that a similar mechanism might exist in rodents and humans, with bone marrow providing stem cells that can generate neurons. However, the relevance of these findings for natural mechanisms underlying adult neurogenesis in mammals is not clear, because of uncertainties at many levels. We argue here that the recent findings in crayfish send a strong signal to re-examine existing data from rodents and humans, and to design new experiments that will directly test the contributions of the immune system to adult neurogenesis in mammals.

  10. Hedgehog signaling activation induces stem cell proliferation and hormone release in the adult pituitary gland.

    PubMed

    Pyczek, Joanna; Buslei, Rolf; Schult, David; Hölsken, Annett; Buchfelder, Michael; Heß, Ina; Hahn, Heidi; Uhmann, Anja

    2016-04-25

    Hedgehog (HH) signaling is known to be essential during the embryonal development of the pituitary gland but the knowledge about its role in the adult pituitary and in associated tumors is sparse. In this report we investigated the effect of excess Hh signaling activation in murine pituitary explants and analyzed the HH signaling status of human adenopituitary lobes and a large cohort of pituitary adenomas. Our data show that excess Hh signaling led to increased proliferation of Sox2(+) and Sox9(+) adult pituitary stem cells and to elevated expression levels of adrenocorticotropic hormone (Acth), growth hormone (Gh) and prolactin (Prl) in the adult gland. Inhibition of the pathway by cyclopamine reversed these effects indicating that active Hh signaling positively regulates proliferative processes of adult pituitary stem cells and hormone production in the anterior pituitary. Since hormone producing cells of the adenohypophysis as well as ACTH-, GH- and PRL-immunopositive adenomas express SHH and its target GLI1, we furthermore propose that excess HH signaling is involved in the development/maintenance of hormone-producing pituitary adenomas. These findings advance the understanding of physiological hormone regulation and may open new treatment options for pituitary tumors.

  11. Hedgehog signaling activation induces stem cell proliferation and hormone release in the adult pituitary gland

    PubMed Central

    Pyczek, Joanna; Buslei, Rolf; Schult, David; Hölsken, Annett; Buchfelder, Michael; Heß, Ina; Hahn, Heidi; Uhmann, Anja

    2016-01-01

    Hedgehog (HH) signaling is known to be essential during the embryonal development of the pituitary gland but the knowledge about its role in the adult pituitary and in associated tumors is sparse. In this report we investigated the effect of excess Hh signaling activation in murine pituitary explants and analyzed the HH signaling status of human adenopituitary lobes and a large cohort of pituitary adenomas. Our data show that excess Hh signaling led to increased proliferation of Sox2+ and Sox9+ adult pituitary stem cells and to elevated expression levels of adrenocorticotropic hormone (Acth), growth hormone (Gh) and prolactin (Prl) in the adult gland. Inhibition of the pathway by cyclopamine reversed these effects indicating that active Hh signaling positively regulates proliferative processes of adult pituitary stem cells and hormone production in the anterior pituitary. Since hormone producing cells of the adenohypophysis as well as ACTH-, GH- and PRL-immunopositive adenomas express SHH and its target GLI1, we furthermore propose that excess HH signaling is involved in the development/maintenance of hormone-producing pituitary adenomas. These findings advance the understanding of physiological hormone regulation and may open new treatment options for pituitary tumors. PMID:27109116

  12. Postnatal stem/progenitor cells derived from the dental pulp of adult chimpanzee

    PubMed Central

    Cheng, Pei-Hsun; Snyder, Brooke; Fillos, Dimitri; Ibegbu, Chris C; Huang, Anderson Hsien-Cheng; Chan, Anthony WS

    2008-01-01

    Background Chimpanzee dental pulp stem/stromal cells (ChDPSCs) are very similar to human bone marrow derived mesenchymal stem/stromal cells (hBMSCs) as demonstrated by the expression pattern of cell surface markers and their multipotent differentiation capability. Results ChDPSCs were isolated from an incisor and a canine of a forty-seven year old female chimpanzee. A homogenous population of ChDPSCs was established in early culture at a high proliferation rate and verified by the expression pattern of thirteen cell surface markers. The ChDPSCs are multipotent and were capable of differentiating into osteogenic, adipogenic and chondrogenic lineages under appropriate in vitro culture conditions. ChDPSCs also express stem cell (Sox-2, Nanog, Rex-1, Oct-4) and osteogenic (Osteonectin, osteocalcin, osteopontin) markers, which is comparable to reported results of rhesus monkey BMSCs (rBMSCs), hBMSCs and hDPSCs. Although ChDPSCs vigorously proliferated during the initial phase and gradually decreased in subsequent passages, the telomere length indicated that telomerase activity was not significantly reduced. Conclusion These results demonstrate that ChDPSCs can be efficiently isolated from post-mortem teeth of adult chimpanzees and are multipotent. Due to the almost identical genome composition of humans and chimpanzees, there is an emergent need for defining the new role of chimpanzee modeling in comparative medicine. Teeth are easy to recover at necropsy and easy to preserve prior to the retrieval of dental pulp for stem/stromal cells isolation. Therefore, the establishment of ChDPSCs would preserve and maximize the applications of such a unique and invaluable animal model, and could advance the understanding of cellular functions and differentiation control of adult stem cells in higher primates. PMID:18430234

  13. Isolation and culture of neural crest stem cells from human hair follicles.

    PubMed

    Yang, Ruifeng; Xu, Xiaowei

    2013-04-06

    Hair follicles undergo lifelong growth and hair cycle is a well-controlled process involving stem cell proliferation and quiescence. Hair bulge is a well-characterized niche for adult stem cells. This segment of the outer root sheath contains a number of different types of stem cells, including epithelial stem cells, melanocyte stem cells and neural crest like stem cells. Hair follicles represent an accessible and rich source for different types of human stem cells. We and others have isolated neural crest stem cells (NCSCs) from human fetal and adult hair follicles. These human stem cells are label-retaining cells and are capable of self-renewal through asymmetric cell division in vitro. They express immature neural crest cell markers but not differentiation markers. Our expression profiling study showed that they share a similar gene expression pattern with murine skin immature neural crest cells. They exhibit clonal multipotency that can give rise to myogenic, melanocytic, and neuronal cell lineages after in vitro clonal single cell culture. Differentiated cells not only acquire lineage-specific markers but also demonstrate appropriate functions in ex vivo conditions. In addition, these NCSCs show differentiation potential toward mesenchymal lineages. Differentiated neuronal cells can persist in mouse brain and retain neuronal differentiation markers. It has been shown that hair follicle derived NCSCs can help nerve regrowth, and they improve motor function in mice transplanted with these stem cells following transecting spinal cord injury. Furthermore, peripheral nerves have been repaired with stem cell grafts, and implantation of skin-derived precursor cells adjacent to crushed sciatic nerves has resulted in remyelination. Therefore, the hair follicle/skin derived NCSCs have already shown promising results for regenerative therapy in preclinical models. Somatic cell reprogramming to induced pluripotent stem (iPS) cells has shown enormous potential for

  14. Simultaneous control of stemness and differentiation by the transcription factor Escargot in adult stem cells: How can we tease them apart?

    PubMed Central

    Loza-Coll, Mariano A.; Jones, D. Leanne

    2016-01-01

    ABSTRACT The homeostatic turnover of adult organs and their regenerative capacity following injury depend on a careful balance between stem cell self-renewal (to maintain or enlarge the stem cell pool) and differentiation (to replace lost tissue). We have recently characterized the role of the Drosophila Snail family transcription factor escargot (esg) in testis cyst stem cells (CySCs)1,2 and intestinal stem cells (ISCs). 3,4 CySCs mutant for esg are not maintained as stem cells, but they remain capable of differentiating normally along the cyst cell lineage. In contrast, esg mutant CySCs that give rise to a closely related lineage, the apical hub cells, cannot maintain hub cell identity. Similarly, Esg maintains stemness of ISCs while regulating the terminal differentiation of progenitor cells into absorptive enterocytes or secretory enteroendocrine cells. Therefore, our findings suggest that Esg may play a conserved and pivotal regulatory role in adult stem cells, controlling both their maintenance and terminal differentiation. Here we propose that this dual regulatory role is due to simultaneous control by Esg of overlapping genetic programs and discuss the exciting challenges and opportunities that lie ahead to explore the underlying mechanisms experimentally. PMID:27077690

  15. Melanocyte-like cells in the heart and pulmonary veins contribute to atrial arrhythmia triggers

    PubMed Central

    Levin, Mark D.; Lu, Min Min; Petrenko, Nataliya B.; Hawkins, Brian J.; Gupta, Tara H.; Lang, Deborah; Buckley, Peter T.; Jochems, Jeanine; Liu, Fang; Spurney, Christopher F.; Yuan, Li J.; Jacobson, Jason T.; Brown, Christopher B.; Huang, Li; Beermann, Friedrich; Margulies, Kenneth B.; Madesh, Muniswamy; Eberwine, James H.; Epstein, Jonathan A.; Patel, Vickas V.

    2009-01-01

    Atrial fibrillation is the most common clinical cardiac arrhythmia. It is often initiated by ectopic beats arising from the pulmonary veins and atrium, but the source and mechanism of these beats remains unclear. The melanin synthesis enzyme dopachrome tautomerase (DCT) is involved in intracellular calcium and reactive species regulation in melanocytes. Given that dysregulation of intracellular calcium and reactive species has been described in patients with atrial fibrillation, we investigated the role of DCT in this process. Here, we characterize a unique DCT-expressing cell population within murine and human hearts that populated the pulmonary veins, atria, and atrioventricular canal. Expression profiling demonstrated that this population expressed adrenergic and muscarinic receptors and displayed transcriptional profiles distinct from dermal melanocytes. Adult mice lacking DCT displayed normal cardiac development but an increased susceptibility to atrial arrhythmias. Cultured primary cardiac melanocyte-like cells were excitable, and those lacking DCT displayed prolonged repolarization with early afterdepolarizations. Furthermore, mice with mutations in the tyrosine kinase receptor Kit lacked cardiac melanocyte-like cells and did not develop atrial arrhythmias in the absence of DCT. These data suggest that dysfunction of melanocyte-like cells in the atrium and pulmonary veins may contribute to atrial arrhythmias. PMID:19855129

  16. UVB represses melanocyte cell migration and acts through β-catenin.

    PubMed

    Bertrand, Juliette U; Petit, Valérie; Hacker, Elke; Berlin, Irina; Hayward, Nicholas K; Pouteaux, Marie; Sage, Evelyne; Whiteman, David C; Larue, Lionel

    2017-02-13

    The exposure of skin to ultraviolet (UV) radiation can have both beneficial and deleterious effects: it can lead, for instance, to increased pigmentation and vitamin D synthesis but also to inflammation and skin cancer. UVB may induce genetic and epigenetic alterations, and have reversible effects associated with post-translational and gene regulation modifications. β-catenin is a main driver in melanocyte development; although infrequently mutated in melanoma, its cellular localization and activity is frequently altered. Here, we evaluate the consequence of UVB on β-catenin in the melanocyte lineage. We report that in vivo, UVB induces cytoplasmic/nuclear relocalization of β-catenin in melanocytes of newborn mice and adult human skin. In mouse melanocyte and human melanoma cell lines in vitro, UVB increases β-catenin stability, accumulation in the nucleus, and co-transcriptional activity, leading to the repression of cell motility and velocity. The activation of the β-catenin signaling pathway and its effect on migration by UVB are increased by an inhibitor of GSK3β, and decreased by an inhibitor of β-catenin. In conclusion, UVB represses melanocyte migration and does so by acting through the GSK3-β-catenin axis. This article is protected by copyright. All rights reserved.

  17. Isolated Rat Epididymal Basal Cells Share Common Properties with Adult Stem Cells1

    PubMed Central

    Mandon, Marion; Hermo, Louis; Cyr, Daniel G.

    2015-01-01

    There is little information on the function of epididymal basal cells. These cells secrete prostaglandins, can metabolize radical oxygen species, and have apical projections that are components of the blood-epididymis barrier. The objective of this study was to develop a reproducible protocol to isolate rat epididymal basal cells and to characterize their function by gene expression profiling. Integrin-alpha6 was used to isolate a highly purified population of basal cells. Microarray analysis indicated that expression levels of 552 genes were enriched in basal cells relative to other cell types. Among these genes, 45 were expressed at levels of 5-fold or greater. These highly expressed genes coded for proteins implicated in cell adhesion, cytoskeletal function, ion transport, cellular signaling, and epidermal function, and included proteases and antiproteases, signal transduction, and transcription factors. Several highly expressed genes have been reported in adult stem cells, suggesting that basal cells may represent an epididymal stem cell population. A basal cell culture was established that showed that these basal cells can differentiate in vitro from keratin (KRT) 5-positive cells to cells that express KRT8 and connexin 26, a marker of columnar cells. These data provide novel information on epididymal basal cell gene expression and suggest that these cells can act as adult stem cells. PMID:26400399

  18. Adult stem cells in the small intestine are intrinsically programmed with their location-specific function.

    PubMed

    Middendorp, Sabine; Schneeberger, Kerstin; Wiegerinck, Caroline L; Mokry, Michal; Akkerman, Ronald D L; van Wijngaarden, Simone; Clevers, Hans; Nieuwenhuis, Edward E S

    2014-05-01

    Differentiation and specialization of epithelial cells in the small intestine are regulated in two ways. First, there is differentiation along the crypt-villus axis of the intestinal stem cells into absorptive enterocytes, Paneth, goblet, tuft, enteroendocrine, or M cells, which is mainly regulated by WNT. Second, there is specialization along the cephalocaudal axis with different absorptive and digestive functions in duodenum, jejunum, and ileum that is controlled by several transcription factors such as GATA4. However, so far it is unknown whether location-specific functional properties are intrinsically programmed within stem cells or if continuous signaling from mesenchymal cells is necessary to maintain the location-specific identity of the small intestine. Using the pure epithelial organoid technique, we show that region-specific gene expression profiles are conserved throughout long-term cultures of both mouse and human intestinal stem cells and correlated with differential Gata4 expression. Furthermore, the human organoid culture system demonstrates that Gata4-regulated gene expression is only allowed in absence of WNT signaling. These data show that location-specific function is intrinsically programmed in the adult stem cells of the small intestine and that their differentiation fate is independent of location-specific extracellular signals. In light of the potential future clinical application of small intestine-derived organoids, our data imply that it is important to generate GATA4-positive and GATA4-negative cultures to regenerate all essential functions of the small intestine.

  19. Growth and differentiation of adult hippocampal arctic ground squirrel neural stem cells.

    PubMed

    Drew, Kelly L; McGee, Rebecca C; Wells, Matthew S; Kelleher-Andersson, Judith A

    2011-01-07

    Arctic ground squirrels (Urocitellus parryii, AGS) are unique in their ability to hibernate with a core body temperature near or below freezing. These animals also resist ischemic injury to the brain in vivo and oxygen-glucose deprivation in vitro. These unique qualities provided the impetus to isolate AGS neurons to examine inherent neuronal characteristics that could account for the capacity of AGS neurons to resist injury and cell death caused by ischemia and extremely cold temperatures. Identifying proteins or gene targets that allow for the distinctive properties of these cells could aid in the discovery of effective therapies for a number of ischemic indications and for the study of cold tolerance. Adult AGS hippocampus contains neural stem cells that continue to proliferate, allowing for easy expansion of these stem cells in culture. We describe here methods by which researchers can utilize these stem cells and differentiated neurons for any number of purposes. By closely following these steps the AGS neural stem cells can be expanded through two passages or more and then differentiated to a culture high in TUJ1-positive neurons (~50%) without utilizing toxic chemicals to minimize the number of dividing cells. Ischemia induces neurogenesis and neurogenesis which proceeds via MEK/ERK and PI3K/Akt survival signaling pathways contributes to ischemia resistance in vivo and in vitro (Kelleher-Anderson, Drew et al., in preparation). Further characterization of these unique neural cells can advance on many fronts, using some or all of these methods.

  20. An RbAp48-like gene regulates adult stem cells in planarians.

    PubMed

    Bonuccelli, Lucia; Rossi, Leonardo; Lena, Annalisa; Scarcelli, Vittoria; Rainaldi, Giuseppe; Evangelista, Monica; Iacopetti, Paola; Gremigni, Vittorio; Salvetti, Alessandra

    2010-03-01

    Retinoblastoma-associated proteins 46 and 48 (RbAp46 and RbAp48) are factors that are components of different chromatin-modelling complexes, such as polycomb repressive complex 2, the activity of which is related to epigenetic gene regulation in stem cells. To date, no direct findings are available on the in vivo role of RbAp48 in stem-cell biology. We recently identified DjRbAp48 - a planarian (Dugesia japonica) homologue of human RBAP48 - expression of which is restricted to the neoblasts, the adult stem cells of planarians. In vivo silencing of DjRbAp48 induces lethality and inability to regenerate, even though neoblasts proliferate and accumulate after wounding. Despite a partial reduction in neoblast number, we were always able to detect a significant number of these cells in DjRbAp48 RNAi animals. Parallel to the decrease in neoblasts, a reduction in the number of differentiated cells and the presence of apoptotic-like neoblasts were detectable in RNAi animals. These findings suggest that DjRbAp48 is not involved in neoblast maintenance, but rather in the regulation of differentiation of stem-cell progeny. We discuss our data, taking into account the possibility that DjRbAp48 might control the expression of genes necessary for cell differentiation by influencing chromatin architecture.

  1. Reversal of developmental restrictions in neural crest lineages: Transition from Schwann cells to glial-melanocytic precursors in vitro

    PubMed Central

    Dupin, Elisabeth; Real, Carla; Glavieux-Pardanaud, Corinne; Vaigot, Pierre; Le Douarin, Nicole M.

    2003-01-01

    In vertebrate embryos, diversification of the lineages arising from the neural crest (NC) is controlled to a large extent by environmental factors. In previous work, we showed that endothelin 3 (ET3) peptide favors the development of glial and melanocytic NC precursors in vitro. This factor is also capable of inducing proliferation of cultured epidermal pigment cells and their conversion to glia. ET3 therefore strongly promotes the emergence of melanocytic and glial phenotypes from precursors and acts on the maintenance of these phenotypes. In the present work, we explored the capacity of ET3 to reprogram glial cells into melanocytes. Schwann cells expressing glial-specific markers [such as the Schwann cell myelin protein (SMP)] were isolated from sciatic nerves of quail embryos and cultured in vitro. We found that ET3 promotes cell growth and sequential expression of melanocyte differentiation markers in cultures of purified SMP-expressing cells, whereas it had no significant effect on SMP-negative cells from the same nerves. Moreover, we provide evidence for the transition of differentiated Schwann cells to melanocytes in clonal cultures. This transition involves the production of a mixed progeny of melanoblasts/melanocytes, glia, and cells bearing differentiation markers of both phenotypes. Therefore, Schwann cells exposed to ET3 transdifferentiate to melanocytes through reversion to the stage of bipotent glial-melanocytic NC precursors. These findings show that NC-derived pigment and glial cells are phenotypically unstable in vitro and may undergo reversal of precursor hierarchy to function as bipotent stem cells. PMID:12702775

  2. "Melanocytic Nests Arising in Lichenoid Inflammation": Reappraisal of the Terminology "Melanocytic Pseudonests".

    PubMed

    Chung, Hye Jin; Simkin, A David; Bhawan, Jag; Wolpowitz, Deon

    2015-12-01

    Pseudonests or pseudomelanocytic nests represent aggregates of cells and cell fragments, including keratinocytes, macrophages, lymphocytes, and occasional melanocytes. Pseudomelanocytic nests in the setting of lichenoid inflammation can mimic atypical melanocytic proliferations. Several reports documented nonspecific staining of pseudonests with melanoma antigen recognized by T cells-1/Melan-A, which can be detected in the cytoplasm of nonmelanocytic cells. In contrast, nuclear stains, such as MITF and SOX10, avoid this nonmelanocyte cytoplasmic staining. The authors have previously proposed the term melanocytic pseudonests to describe junctional nests with numerous (>2) true melanoma antigen recognized by T cells-1/Melan-A, SOX10, and MITF in a nonmelanocytic lesion with lichenoid inflammation (unilateral lichen planus pigmentosus/erythema dyschromicum perstans). In this study, the authors report another case of this phenomenon arising in a different lichenoid inflammatory dermatitis (lichen planus). The immunophenotype and number of clustered true melanocytes indicate that these dermoepidermal aggregates represent true melanocytic nests and not pseudonests of any type. Therefore, the authors propose the revised terminology of "melanocytic nests arising in lichenoid inflammation" to describe this novel pattern of benign melanocytic reorganization or proliferation in a subset of lichenoid dermatitides. Because this phenomenon can mimic atypical melanocytic proliferations, clinicopathologic correlation is essential for the correct diagnosis.

  3. Melanocytic Nests Arising in Lichenoid Inflammation”: Reappraisal of the Terminology “Melanocytic Pseudonests”

    PubMed Central

    Chung, Hye Jin; Simkin, A. David; Bhawan, Jag

    2015-01-01

    Abstract: Pseudonests or pseudomelanocytic nests represent aggregates of cells and cell fragments, including keratinocytes, macrophages, lymphocytes, and occasional melanocytes. Pseudomelanocytic nests in the setting of lichenoid inflammation can mimic atypical melanocytic proliferations. Several reports documented nonspecific staining of pseudonests with melanoma antigen recognized by T cells-1/Melan-A, which can be detected in the cytoplasm of nonmelanocytic cells. In contrast, nuclear stains, such as MITF and SOX10, avoid this nonmelanocyte cytoplasmic staining. The authors have previously proposed the term melanocytic pseudonests to describe junctional nests with numerous (>2) true melanoma antigen recognized by T cells-1/Melan-A, SOX10, and MITF in a nonmelanocytic lesion with lichenoid inflammation (unilateral lichen planus pigmentosus/erythema dyschromicum perstans). In this study, the authors report another case of this phenomenon arising in a different lichenoid inflammatory dermatitis (lichen planus). The immunophenotype and number of clustered true melanocytes indicate that these dermoepidermal aggregates represent true melanocytic nests and not pseudonests of any type. Therefore, the authors propose the revised terminology of “melanocytic nests arising in lichenoid inflammation” to describe this novel pattern of benign melanocytic reorganization or proliferation in a subset of lichenoid dermatitides. Because this phenomenon can mimic atypical melanocytic proliferations, clinicopathologic correlation is essential for the correct diagnosis. PMID:26588340

  4. The postnatal origin of adult neural stem cells and the effects of glucocorticoids on their genesis.

    PubMed

    Ortega-Martínez, Sylvia; Trejo, José L

    2015-02-15

    The relevance of adult neurogenesis in hippocampal function is well documented, as is the potential impact stress has on the adult neurogenic niche. Adult born neurons are generated from neural precursors in the dentate gyrus (DG), although the point in postnatal development that these cell precursors originate is not known. This is particularly relevant if we consider the effects stress may have on the development of neural precursors, and whether such effects on adult neurogenesis and behavior may persist in the long-term. We have analyzed the proportion of neural precursors in the adult murine hippocampus born on specific days during postnatal development using a dual birth-dating analysis, and we assessed their sensitivity to dexamethasone (DEX) on the peak day of cell generation. We also studied the consequences of postnatal DEX administration on adult hippocampal-dependent behavior. Postnatal day 6 (P6) is a preferred period for proliferating neural stem cells (NSCs) to become the precursors that remain in a proliferative state throughout adulthood. This window is independent of gender, the cell's location in the DG granule cell layer or their rostro-caudal position. DEX administration at P6 reduces the size of the adult NSC pool in the DG, which is correlated with poor learning/memory capacity and increased anxiety-like behavior. These results indicate that aNSCs are generated non-uniformly during postnatal development, with peak generation on day P6, and that stress receptor activation during the key period of postnatal NSC generation has a profound impact on both adult hippocampal neurogenesis and behavior.

  5. Harnessing the potential of adult cardiac stem cells: lessons from haematopoiesis, the embryo and the niche.

    PubMed

    Balmer, Gemma M; Riley, Paul R

    2012-10-01

    Across biomedicine, there is a major drive to develop stem cell (SC) treatments for debilitating diseases. Most effective treatments restore an embryonic phenotype to adult SCs. This has led to two emerging paradigms in SC biology: the application of developmental biology studies and the manipulation of the SC niche. Developmental studies can reveal how SCs are orchestrated to build organs, the understanding of which is important in order to instigate tissue repair in the adult. SC niche studies can reveal cues that maintain SC 'stemness' and how SCs may be released from the constraints of the niche to differentiate and repopulate a 'failing' organ. The haematopoietic system provides an exemplar whereby characterisation of the blood lineages during development and the bone marrow niche has resulted in therapeutics now routinely used in the clinic. Ischaemic heart disease is a major cause of morbidity and mortality in humans and the question remains as to whether these principles can be applied to the heart, in order to exploit the potential of adult SCs for use in cardiovascular repair and regeneration.

  6. Endometrial adult/progenitor stem cells: pathogenetic theory and new antiangiogenic approach for endometriosis therapy.

    PubMed

    Pittatore, G; Moggio, A; Benedetto, C; Bussolati, B; Revelli, A

    2014-03-01

    The cyclical arrival of endometrial cells into the abdominal cavity through retrograde flux at menstruation represents the etiopathogenetic basis of endometriosis. The endometrium has peculiar regenerative properties linked to the presence of adult stem cells similar to mesenchymal stem cells (MSCs). Once in the abdominal cavity, these MSCs could proliferate, invade, and differentiate into endometrial cells, finally generating ectopic implants. As only differentiated endometrial cells, and not endometrial MSCs, possess steroid hormone receptors, MSCs could be responsible for the high rate of persistence/recurrence of the disease after hypoestrogenism-inducing therapies. Even angiogenesis promoted by MSCs could play an important role, as survival and proliferation of endometriotic tissue depend on the formation of new blood vessels. Inhibition of angiogenesis represents, in fact, a new, promising therapeutic approach for the disease. Further, medications directly targeting endometriosis MSCs could be effective, alone or in association with hormonal treatments, in increasing the success of medical treatment.

  7. Adult stem cells, scaffolds for in vivo and in vitro myocardial tissue engineering.

    PubMed

    Di Felice, Valentina; De Luca, Angela; Serradifalco, Claudia; Di Marco, Patrizia; Verin, Lucia; Motta, Antonella; Guercio, Annalisa; Zummo, Giovanni

    2010-01-01

    The main goal in the last few years in cardiac research has been to isolate cardiac potential stem cells from adult myocardium and to demonstrate their differentiation potential. We have previously demonstrated that c-Kit positive cardiac stem cells are able to organize themselves into a tissue-like cell mass. In this 3D mass, they can produce a high concentration of natural extracellular matrix, can create vessels, a capsule and, with the help of an Open-pore Polylactic Acid scaffold, many cells can organize an elementary myocardium. Drawing from this background, we decided to design and use poly-lactic scaffolds and the model of the athymic Nude-Foxn1(nu) mouse to evaluate the extent of the myogenic vs endothelial differentiation in vivo, and to evaluate the presence or the absence of a foreign body reaction.

  8. Inductive interactions mediated by interplay of asymmetric signalling underlie development of adult haematopoietic stem cells

    PubMed Central

    Souilhol, Céline; Gonneau, Christèle; Lendinez, Javier G.; Batsivari, Antoniana; Rybtsov, Stanislav; Wilson, Heather; Morgado-Palacin, Lucia; Hills, David; Taoudi, Samir; Antonchuk, Jennifer; Zhao, Suling; Medvinsky, Alexander

    2016-01-01

    During embryonic development, adult haematopoietic stem cells (HSCs) emerge preferentially in the ventral domain of the aorta in the aorta–gonad–mesonephros (AGM) region. Several signalling pathways such as Notch, Wnt, Shh and RA are implicated in this process, yet how these interact to regulate the emergence of HSCs has not previously been described in mammals. Using a combination of ex vivo and in vivo approaches, we report here that stage-specific reciprocal dorso–ventral inductive interactions and lateral input from the urogenital ridges are required to drive HSC development in the aorta. Our study strongly suggests that these inductive interactions in the AGM region are mediated by the interplay between spatially polarized signalling pathways. Specifically, Shh produced in the dorsal region of the AGM, stem cell factor in the ventral and lateral regions, and BMP inhibitory signals in the ventral tissue are integral parts of the regulatory system involved in the development of HSCs. PMID:26952187

  9. Fragile x mental retardation protein regulates proliferation and differentiation of adult neural stem/progenitor cells.

    PubMed

    Luo, Yuping; Shan, Ge; Guo, Weixiang; Smrt, Richard D; Johnson, Eric B; Li, Xuekun; Pfeiffer, Rebecca L; Szulwach, Keith E; Duan, Ranhui; Barkho, Basam Z; Li, Wendi; Liu, Changmei; Jin, Peng; Zhao, Xinyu

    2010-04-08

    Fragile X syndrome (FXS), the most common form of inherited mental retardation, is caused by the loss of functional fragile X mental retardation protein (FMRP). FMRP is an RNA-binding protein that can regulate the translation of specific mRNAs. Adult neurogenesis, a process considered important for neuroplasticity and memory, is regulated at multiple molecular levels. In this study, we investigated whether Fmrp deficiency affects adult neurogenesis. We show that in a mouse model of fragile X syndrome, adult neurogenesis is indeed altered. The loss of Fmrp increases the proliferation and alters the fate specification of adult neural progenitor/stem cells (aNPCs). We demonstrate that Fmrp regulates the protein expression of several components critical for aNPC function, including CDK4 and GSK3beta. Dysregulation of GSK3beta led to reduced Wnt signaling pathway activity, which altered the expression of neurogenin1 and the fate specification of aNPCs. These data unveil a novel regulatory role for Fmrp and translational regulation in adult neurogenesis.

  10. Multipotent stem cells isolated from the adult mouse retina are capable of producing functional photoreceptor cells.

    PubMed

    Li, Tianqing; Lewallen, Michelle; Chen, Shuyi; Yu, Wei; Zhang, Nian; Xie, Ting

    2013-06-01

    Various stem cell types have been tested for their potential application in treating photoreceptor degenerative diseases, such as retinitis pigmentosa (RP) and age-related macular degeneration (AMD). Only embryonic stem cells (ESCs) have so far been shown to generate functional photoreceptor cells restoring light response of photoreceptor-deficient mice, but there is still some concern of tumor formation. In this study, we have successfully cultured Nestin(+)Sox2(+)Pax6(+) multipotent retinal stem cells (RSCs) from the adult mouse retina, which are capable of producing functional photoreceptor cells that restore the light response of photoreceptor-deficient rd1 mutant mice following transplantation. After they have been expanded for over 35 passages in the presence of FGF and EGF, the cultured RSCs still maintain stable proliferation and differentiation potential. Under proper differentiation conditions, they can differentiate into all the major retinal cell types found in the adult retina. More importantly, they can efficiently differentiate into photoreceptor cells under optimized differentiation conditions. Following transplantation into the subretinal space of slowly degenerating rd7 mutant eyes, RSC-derived photoreceptor cells integrate into the retina, morphologically resembling endogenous photoreceptors and forming synapases with resident retinal neurons. When transplanted into eyes of photoreceptor-deficient rd1 mutant mice, a RP model, RSC-derived photoreceptors can partially restore light response, indicating that those RSC-derived photoreceptors are functional. Finally, there is no evidence for tumor formation in the photoreceptor-transplanted eyes. Therefore, this study has demonstrated that RSCs isolated from the adult retina have the potential of producing functional photoreceptor cells that can potentially restore lost vision caused by loss of photoreceptor cells in RP and AMD.

  11. Allogeneic hematopoietic stem-cell transplantation for adult and adolescent hemophagocytic lymphohistiocytosis: a single center analysis.

    PubMed

    Fu, Li; Wang, Jingshi; Wei, Na; Wu, Lin; Wang, Yini; Huang, Wenqiu; Zhang, Jia; Liu, Jinli; Wang, Zhao

    2016-11-01

    Myeloablative conditioning-based allogeneic hematopoietic stem-cell transplantation (allo-HSCT) in the treatment of adult and adolescent hemophagocytic lymphohistiocytosis (HLH) is rarely reported. We conducted a retrospective study of 30 adult and adolescent HLH transplanted for primary HLH (n = 4), tumor-HLH (n = 8), EBV-HLH (n = 14), and underlying disease-unknown (UDU)-HLH (n = 4). Peripheral blood stem cells (PBSCs) were the stem-cell source in all patients. Twenty-three patients were transplanted from HLA-haploidentical family donors, six from HLA-identical sibling donors, and one from a matched unrelated donor. Four patients appeared with mixed chimerism (MC), and no patient presented with graft failure. There was a high risk for EBV reactivation with an incidence of 47 %. Two patients developed post-transplant lymphoproliferative disorder (PTLD) and three were considered primary disease recurrent. With a median follow-up of 26 months, 19 patients survived and 11 patients died. The estimated 2-year overall survival (OS) was 63.3 ± 8.8 % in all patients, 100 % in primary HLH, 64.3 ± 12.8 % in EBV-HLH, 50.0 ± 17.7 % in tumor-HLH, and 50.0 ± 25.0 % in UDU-HLH. Myeloablative conditioning-based allo-HSCT is an effective treatment for adult and adolescent HLH to achieve complete remission and long-term survival.

  12. Development and specification of cerebellar stem and progenitor cells in zebrafish: from embryo to adult

    PubMed Central

    2013-01-01

    Background Teleost fish display widespread post-embryonic neurogenesis originating from many different proliferative niches that are distributed along the brain axis. During the development of the central nervous system (CNS) different cell types are produced in a strict temporal order from increasingly committed progenitors. However, it is not known whether diverse neural stem and progenitor cell types with restricted potential or stem cells with broad potential are maintained in the teleost fish brain. Results To study the diversity and output of neural stem and progenitor cell populations in the zebrafish brain the cerebellum was used as a model brain region, because of its well-known architecture and development. Transgenic zebrafish lines, in vivo imaging and molecular markers were used to follow and quantify how the proliferative activity and output of cerebellar progenitor populations progress. This analysis revealed that the proliferative activity and progenitor marker expression declines in juvenile zebrafish before they reach sexual maturity. Furthermore, this correlated with the diminished repertoire of cell types produced in the adult. The stem and progenitor cells derived from the upper rhombic lip were maintained into adulthood and they actively produced granule cells. Ventricular zone derived progenitor cells were largely quiescent in the adult cerebellum and produced a very limited number of glia and inhibitory inter-neurons. No Purkinje or Eurydendroid cells were produced in fish older than 3 months. This suggests that cerebellar cell types are produced in a strict temporal order from distinct pools of increasingly committed stem and progenitor cells. Conclusions Our results in the zebrafish cerebellum show that neural stem and progenitor cell types are specified and they produce distinct cell lineages and sub-types of brain cells. We propose that only specific subtypes of brain cells are continuously produced throughout life in the teleost fish

  13. Leucine-rich repeat-containing G-protein-coupled receptors as markers of adult stem cells.

    PubMed

    Barker, Nick; Clevers, Hans

    2010-05-01

    Molecular markers are used to characterize and track adult stem cells. Colon cancer research has led to the identification of 2 related receptors, leucine-rich repeat-containing, G-protein-coupled receptors (Lgr)5 and Lgr6, that are expressed by small populations of cells in a variety of adult organs. Genetic mouse models have allowed the visualization, isolation, and genetic marking of Lgr5(+ve) and Lgr6(+ve) cells and provided evidence that they are stem cells. The Lgr5(+ve) cells were found to occupy locations not commonly associated with stem cells in the stomach, small intestine, colon, and hair follicles. A multipotent population of skin stem cells express Lgr6. Single Lgr5(+ve) stem cells from the small intestine and the stomach can be cultured into long-lived organoids. Further studies of these markers might reveal adult stem cell populations in additional tissues. Identification of the ligands for Lgr5 and 6 will help elucidate stem cell functions and modes of intracellular signaling.

  14. Defining a developmental path to neural fate by global expression profiling of mouse embryonic stem cells and adult neural stem/progenitor cells.

    PubMed

    Aiba, Kazuhiro; Sharov, Alexei A; Carter, Mark G; Foroni, Chiara; Vescovi, Angelo L; Ko, Minoru S H

    2006-04-01

    To understand global features of gene expression changes during in vitro neural differentiation, we carried out the microarray analysis of embryonic stem cells (ESCs), embryonal carcinoma cells, and adult neural stem/progenitor (NS) cells. Expression profiling of ESCs during differentiation in monolayer culture revealed three distinct phases: undifferentiated ESCs, primitive ectoderm-like cells, and neural progenitor cells. Principal component (PC) analysis revealed that these cells were aligned on PC1 over the course of 6 days. This PC1 represents approximately 4,000 genes, the expression of which increased with neural commitment/differentiation. Furthermore, NS cells derived from adult brain and their differentiated cells were positioned along this PC axis further away from undifferentiated ESCs than embryonic stem-derived neural progenitors. We suggest that this PC1 defines a path to neural fate, providing a scale for the degree of commitment/differentiation.

  15. Preparation of adult muscle fiber-associated stem/precursor cells.

    PubMed

    Conboy, Michael J; Conboy, Irina M

    2010-01-01

    In our studies of muscle regeneration we have developed, modified, and optimized techniques to isolate and study the stem and precursor cells to muscle tissue. Our goals have been to obtain for study muscle fibers in bulk, or the fiber-associated cells, separately from the other cells found in muscle. Using these techniques, myofiber-associated cells may be isolated from neonatal through adult muscle, from resting or from regenerating muscle, thus allowing one to investigate the cellular populations participating during the time course of these events. The protocol is applicable to any age and condition of muscle and may be adapted for other tissues.

  16. Clonogenic neoblasts are pluripotent adult stem cells that underlie planarian regeneration.

    PubMed

    Wagner, Daniel E; Wang, Irving E; Reddien, Peter W

    2011-05-13

    Pluripotent cells in the embryo can generate all cell types, but lineage-restricted cells are generally thought to replenish adult tissues. Planarians are flatworms and regenerate from tiny body fragments, a process requiring a population of proliferating cells (neoblasts). Whether regeneration is accomplished by pluripotent cells or by the collective activity of multiple lineage-restricted cell types is unknown. We used ionizing radiation and single-cell transplantation to identify neoblasts that can form large descendant-cell colonies in vivo. These clonogenic neoblasts (cNeoblasts) produce cells that differentiate into neuronal, intestinal, and other known postmitotic cell types and are distributed throughout the body. Single transplanted cNeoblasts restored regeneration in lethally irradiated hosts. We conclude that broadly distributed, adult pluripotent stem cells underlie the remarkable regenerative abilities of planarians.

  17. The ventral hippocampus is the embryonic origin for adult neural stem cells in the dentate gyrus.

    PubMed

    Li, Guangnan; Fang, Li; Fernández, Gloria; Pleasure, Samuel J

    2013-05-22

    Adult neurogenesis represents a unique form of plasticity in the dentate gyrus requiring the presence of long-lived neural stem cells (LL-NSCs). However, the embryonic origin of these LL-NSCs remains unclear. The prevailing model assumes that the dentate neuroepithelium throughout the longitudinal axis of the hippocampus generates both the LL-NSCs and embryonically produced granule neurons. Here we show that the NSCs initially originate from the ventral hippocampus during late gestation and then relocate into the dorsal hippocampus. The descendants of these cells are the source for the LL-NSCs in the subgranular zone (SGZ). Furthermore, we show that the origin of these cells and their maintenance in the dentate are controlled by distinct sources of Sonic Hedgehog (Shh). The revelation of the complexity of both the embryonic origin of hippocampal LL-NSCs and the sources of Shh has important implications for the functions of LL-NSCs in the adult hippocampus.

  18. Links between Schwann cells and melanocytes in development and disease.

    PubMed

    Van Raamsdonk, Catherine D; Deo, Mugdha

    2013-09-01

    Melanocytes are pigment-producing cells that reside in the skin, eyes, ears, heart, and central nervous system meninges of mammals. Schwann cells are glial cells, which closely associate with peripheral nerves, myelinating, and sheathing them. Melanocytes and Schwann cells both arise from the neural crest during development, and some melanocytes arise directly from Schwann cell precursors lining developing spinal nerves. In this review, we explore the connections between melanocytes and Schwann cells in development and transformation.

  19. Polycaprolactone fiber meshes provide a 3D environment suitable for cultivation and differentiation of melanocytes from the outer root sheath of hair follicle.

    PubMed

    Savkovic, Vuk; Flämig, Franziska; Schneider, Marie; Sülflow, Katharina; Loth, Tina; Lohrenz, Andrea; Hacker, Michael Christian; Schulz-Siegmund, Michaela; Simon, Jan-Christoph

    2016-01-01

    Melanocytes differentiated from the stem cells of human hair follicle outer root sheath (ORS) have the potential for developing non-invasive treatments for skin disorders out of a minimal sample: of hair root. With a robust procedure for melanocyte cultivation from the ORS of human hair follicle at hand, this study focused on the identification of a suitable biocompatible, biodegradable carrier as the next step toward their clinical implementation. Polycaprolactone (PCL) is a known biocompatible material used for a number of medical devices. In this study, we have populated electrospun PCL fiber meshes with normal human epidermal melanocytes (NHEM) as well as with hair-follicle-derived human melanocytes from the outer root sheath (HUMORS) and tested their functionality in vitro. PCL fiber meshes evidently provided a niche for melanocytes and supported their melanotic properties. The cells were tested for gene expression of PAX3, PMEL, TYR and MITF, as well as for proliferation, expression of melanocyte marker proteins tyrosinase and glycoprotein 100 (gp100), L-DOPA-tautomerase enzymatic activity and melanin content. Reduced mitochondrial activity and PAX-3 gene expression indicated that the three-dimensional PCL scaffold supported differentiation rather than proliferation of melanocytes. The monitored melanotic features of both the NHEM and HUMORS cultivated on PCL scaffolds significantly exceeded those of two-dimensional adherent cultures.

  20. The Influence of Modified Silica Nanomaterials on Adult Stem Cell Culture

    PubMed Central

    Tarpani, Luigi; Morena, Francesco; Gambucci, Marta; Zampini, Giulia; Massaro, Giuseppina; Argentati, Chiara; Emiliani, Carla; Martino, Sabata; Latterini, Loredana

    2016-01-01

    The preparation of tailored nanomaterials able to support cell growth and viability is mandatory for tissue engineering applications. In the present work, silica nanoparticles were prepared by a sol-gel procedure and were then functionalized by condensation of amino groups and by adsorption of silver nanoparticles. Transmission electron microscopy (TEM) imaging was used to establish the morphology and the average dimensions of about 130 nm, which were not affected by the functionalization. The three silica samples were deposited (1 mg/mL) on cover glasses, which were used as a substrate to culture adult human bone marrow-mesenchymal stem cells (hBM-MSCs) and human adipose-derived stem cells (hASCs). The good cell viability over the different silica surfaces was evaluated by monitoring the mitochondrial dehydrogenase activity. The analysis of the morphological parameters (aspect ratio, cell length, and nuclear shape Index) yielded information about the interactions of stem cells with the surface of three different nanoparticles. The data are discussed in terms of chemical properties of the surface of silica nanoparticles.

  1. Effects of ECM protein micropatterns on the migration and differentiation of adult neural stem cells.

    PubMed

    Joo, Sunghoon; Kim, Joo Yeon; Lee, Eunsoo; Hong, Nari; Sun, Woong; Nam, Yoonkey

    2015-08-12

    The migration and differentiation of adult neural stem cells (aNSCs) are believed to be strongly influenced by the spatial distribution of extracellular matrix (ECM) proteins in the stem cell niche. In vitro culture platform, which involves the specific spatial distribution of ECM protein, could offer novel tools for better understanding of aNSC behavior in the spatial pattern of ECM proteins. In this work, we applied soft-lithographic technique to design simple and reproducible laminin (LN)-polylysine cell culture substrates and investigated how aNSCs respond to the various spatial distribution of laminin, one of ECM proteins enriched in the aNSC niche. We found that aNSC preferred to migrate and attach to LN stripes, and aNSC-derived neurons and astrocytes showed significant difference in motility towards LN stripes. By changing the spacing of LN stripes, we were able to control the alignment of neurons and astrocytes. To the best of our knowledge, this is the first time to investigate the differential cellular responses of aNSCs on ECM protein (LN) and cell adhesive synthetic polymer (PDL) using surface micropatterns. Our findings would provide a deeper understanding in astrocyte-neuron interactions as well as ECM-stem cell interactions.

  2. Xenobiotic effects on intestinal stem cell proliferation in adult honey bee (Apis mellifera L) workers.

    PubMed

    Forkpah, Cordelia; Dixon, Luke R; Fahrbach, Susan E; Rueppell, Olav

    2014-01-01

    The causes of the current global decline in honey bee health are unknown. One major group of hypotheses invokes the pesticides and other xenobiotics to which this important pollinator species is often exposed. Most studies have focused on mortality or behavioral deficiencies in exposed honey bees while neglecting other biological functions and target organs. The midgut epithelium of honey bees presents an important interface between the insect and its environment. It is maintained by proliferation of intestinal stem cells throughout the adult life of honey bees. We used caged honey bees to test multiple xenobiotics for effects on the replicative activity of the intestinal stem cells under laboratory conditions. Most of the tested compounds did not alter the replicative activity of intestinal stem cells. However, colchicine, methoxyfenozide, tetracycline, and a combination of coumaphos and tau-fluvalinate significantly affected proliferation rate. All substances except methoxyfenozide decreased proliferation rate. Thus, the results indicate that some xenobiotics frequently used in apiculture and known to accumulate in honey bee hives may have hitherto unknown physiological effects. The nutritional status and the susceptibility to pathogens of honey bees could be compromised by the impacts of xenobiotics on the maintenance of the midgut epithelium. This study contributes to a growing body of evidence that more comprehensive testing of xenobiotics may be required before novel or existing compounds can be considered safe for honey bees and other non-target species.

  3. Xenobiotic Effects on Intestinal Stem Cell Proliferation in Adult Honey Bee (Apis mellifera L) Workers

    PubMed Central

    Forkpah, Cordelia; Dixon, Luke R.; Fahrbach, Susan E.; Rueppell, Olav

    2014-01-01

    The causes of the current global decline in honey bee health are unknown. One major group of hypotheses invokes the pesticides and other xenobiotics to which this important pollinator species is often exposed. Most studies have focused on mortality or behavioral deficiencies in exposed honey bees while neglecting other biological functions and target organs. The midgut epithelium of honey bees presents an important interface between the insect and its environment. It is maintained by proliferation of intestinal stem cells throughout the adult life of honey bees. We used caged honey bees to test multiple xenobiotics for effects on the replicative activity of the intestinal stem cells under laboratory conditions. Most of the tested compounds did not alter the replicative activity of intestinal stem cells. However, colchicine, methoxyfenozide, tetracycline, and a combination of coumaphos and tau-fluvalinate significantly affected proliferation rate. All substances except methoxyfenozide decreased proliferation rate. Thus, the results indicate that some xenobiotics frequently used in apiculture and known to accumulate in honey bee hives may have hitherto unknown physiological effects. The nutritional status and the susceptibility to pathogens of honey bees could be compromised by the impacts of xenobiotics on the maintenance of the midgut epithelium. This study contributes to a growing body of evidence that more comprehensive testing of xenobiotics may be required before novel or existing compounds can be considered safe for honey bees and other non-target species. PMID:24608542

  4. Heterochromatin protein 1 promotes self-renewal and triggers regenerative proliferation in adult stem cells.

    PubMed

    Zeng, An; Li, Yong-Qin; Wang, Chen; Han, Xiao-Shuai; Li, Ge; Wang, Jian-Yong; Li, Dang-Sheng; Qin, Yong-Wen; Shi, Yufang; Brewer, Gary; Jing, Qing

    2013-04-29

    Adult stem cells (ASCs) capable of self-renewal and differentiation confer the potential of tissues to regenerate damaged parts. Epigenetic regulation is essential for driving cell fate decisions by rapidly and reversibly modulating gene expression programs. However, it remains unclear how epigenetic factors elicit ASC-driven regeneration. In this paper, we report that an RNA interference screen against 205 chromatin regulators identified 12 proteins essential for ASC function and regeneration in planarians. Surprisingly, the HP1-like protein SMED-HP1-1 (HP1-1) specifically marked self-renewing, pluripotent ASCs, and HP1-1 depletion abrogated self-renewal and promoted differentiation. Upon injury, HP1-1 expression increased and elicited increased ASC expression of Mcm5 through functional association with the FACT (facilitates chromatin transcription) complex, which consequently triggered proliferation of ASCs and initiated blastema formation. Our observations uncover an epigenetic network underlying ASC regulation in planarians and reveal that an HP1 protein is a key chromatin factor controlling stem cell function. These results provide important insights into how epigenetic mechanisms orchestrate stem cell responses during tissue regeneration.

  5. Adverse Late and Long-Term Treatment Effects in Adult Allogeneic Hematopoietic Stem Cell Transplant Survivors.

    PubMed

    Mosesso, Kara

    2015-11-01

    Hematopoietic stem cell transplantation (HSCT) has become the standard of care for many malignant and nonmalignant hematologic diseases that don't respond to traditional therapy. There are two types: autologous transplantation (auto-HSCT), in which an individual's stem cells are collected, stored, and infused back into that person; and allogeneic transplantation (allo-HSCT), in which healthy donor stem cells are infused into a recipient whose bone marrow has been damaged or destroyed. There have been numerous advancements in this field, leading to marked increases in the number of transplants performed annually. This article--the first of several on cancer survivorship--focuses on the care of adult allo-HSCT survivors because of the greater complexity of their posttransplant course. The author summarizes potential adverse late and long-term treatment-related effects, with special focus on the evaluation and management of several cardiovascular disease risk factors that can occur either independently or concurrently as part of the metabolic syndrome. These risk factors are potentially modifiable with appropriate nursing interventions and lifestyle modifications.

  6. Embryonic origin of adult stem cells required for tissue homeostasis and regeneration

    PubMed Central

    Davies, Erin L; Lei, Kai; Seidel, Christopher W; Kroesen, Amanda E; McKinney, Sean A; Guo, Longhua; Robb, Sofia MC; Ross, Eric J; Gotting, Kirsten; Alvarado, Alejandro Sánchez

    2017-01-01

    Planarian neoblasts are pluripotent, adult somatic stem cells and lineage-primed progenitors that are required for the production and maintenance of all differentiated cell types, including the germline. Neoblasts, originally defined as undifferentiated cells residing in the adult parenchyma, are frequently compared to embryonic stem cells yet their developmental origin remains obscure. We investigated the provenance of neoblasts during Schmidtea mediterranea embryogenesis, and report that neoblasts arise from an anarchic, cycling piwi-1+ population wholly responsible for production of all temporary and definitive organs during embryogenesis. Early embryonic piwi-1+ cells are molecularly and functionally distinct from neoblasts: they express unique cohorts of early embryo enriched transcripts and behave differently than neoblasts in cell transplantation assays. Neoblast lineages arise as organogenesis begins and are required for construction of all major organ systems during embryogenesis. These subpopulations are continuously generated during adulthood, where they act as agents of tissue homeostasis and regeneration. DOI: http://dx.doi.org/10.7554/eLife.21052.001 PMID:28072387

  7. β-Cell neogenesis: experimental considerations in adult stem cell differentiation.

    PubMed

    Iskovich, Svetlana; Goldenberg-Cohen, Nitza; Stein, Jerry; Yaniv, Isaac; Farkas, Daniel L; Askenasy, Nadir

    2011-04-01

    The contribution of stem cells derived from adult tissues to the recovery of pancreatic islets from chemical injury is controversial. Analysis of nonhematopoietic differentiation of bone marrow-derived cells has yielded positive and negative results under different experimental conditions. Using the smallest subset of bone marrow cells lacking immuno-hematopoietic lineage markers, we have detected incorporation and conversion into insulin-producing cells. Donor cells identified by genomic markers silence green fluorescent protein (GFP) expression as a feature of differentiation, in parallel to expressing PDX-1 and proinsulin. Here we elaborate potential experimental difficulties that might result in false-negative results. The use of GFP as a reporter protein is suboptimal for differentiation experiments: (a) the bone marrow of GFP donors partially expresses the reporter protein, (b) differentiating bone marrow cells silence GFP expression, and (c) the endocrine pancreas is constitutively negative for GFP. In addition, design of the experiments, data analysis, and interpretation encounter numerous objective and subjective difficulties. Rigorous evaluation under optimized experimental conditions confirms the capacity of adult bone marrow-derived stem cells to adopt endocrine developmental traits, and demonstrates that GFP downregulation and silencing is a feature of differentiation.

  8. The effect of substrate stiffness on adult neural stem cell behavior.

    PubMed

    Leipzig, Nic D; Shoichet, Molly S

    2009-12-01

    Adult stem cells reside in unique niches that provide vital cues for their survival, self-renewal and differentiation. In order to better understand the contribution of substrate stiffness to neural stem/progenitor cell (NSPC) differentiation and proliferation, a photopolymerizable methacrylamide chitosan (MAC) biomaterial was developed. Photopolymerizable MAC is particularly compelling for the study of the central nervous system stem cell niche because Young's elastic modulus (E(Y)) can be tuned from less than 1 kPa to greater than 30 kPa. Additionally, the numerous free amine functional groups enable inclusion of biochemical signaling molecules that, together with the mechanical environment, influence cell behavior. Herein, NSPCs proliferated on MAC substrates with Young's elastic moduli below 10 kPa and exhibited maximal proliferation on 3.5 kPa surfaces. Neuronal differentiation was favored on the soft est surfaces with E(Y) < 1 kPa as confirmed by both immunohistochemistry and qRT-PCR. Oligodendrocyte differentiation was favored on stiffer scaffolds (> 7 kPa); however, myelin oligodendrocyte glycoprotein (MOG) gene expression suggested that oligodendrocyte maturation and myelination was best on < 1 kPa scaffolds where more mature neurons were present. Astrocyte differentiation was only observed on < 1 and 3.5 kPa surfaces and represented less than 2% of the total cell population. This work demonstrates the importance of substrate stiffness to the proliferation and differentiation of adult NSPCs and highlights the importance of mechanical properties to the success of scaffolds designed to engineer central nervous system tissue.

  9. Autologous Transplantation of Adult Mice Spermatogonial Stem Cells into Gamma Irradiated Testes

    PubMed Central

    Koruji, Morteza; Movahedin, Mansoureh; Mowla, Seyed Javad; Gourabi, Hamid; Pour-Beiranvand, Shahram; Jabbari Arfaee, Ali

    2012-01-01

    Objective: We evaluated structural and functional changes of fresh and frozen-thawed adult mouse spermatogonial stem cells following auto-transplantation into gamma-irradiated testes. Materials and Methods: In this experimental research, the right testes from adult mice (n=25) were collected, then Sertoli and spermatogonial cells were isolated using two-step enzymatic digestion, lectin immobilization and differential plating. Three weeks after cultivation, the Bromodeoxyuridine (BrdU)-labeled spermatogonial cells were transplanted, via rete testis, into the other testis of the same mouse, which had been irradiated with 14Gy. The mice were transplanted with: fresh cells (control 1), fresh cells co-cultured with Sertoli cells (control 2), the frozen-thawed cells (experimental 1) and frozen-thawed cells co-cultured with Sertoli cells (experimental 2). The morphological changes between different transplanted testes groups were compared in 8 weeks after transplantation. The statistical significance between mean values was determined by Kruskal Wallis and one-way analysis of variance in efficiency of transplantation. Results: The statistical analysis revealed significant increases in the mean percentage of testis weight and normal seminiferous tubules following spermatogonial stem cells transplantation in the recipient'fs testes. The normal seminiferous tubules percentage in the co-culture system with fresh cells and frozen-thawed groups were more than those in non-transplanted and fresh cell transplanted groups (p≤0.001). Conclusion: Our results demonstrated that spermatogonial stem cells in the colonies could result sperm production in the recipient’s testes after autologous transplantation. PMID:23507977

  10. The behaviour of Drosophila adult hindgut stem cells is controlled by Wnt and Hh signalling.

    PubMed

    Takashima, Shigeo; Mkrtchyan, Marianna; Younossi-Hartenstein, Amelia; Merriam, John R; Hartenstein, Volker

    2008-07-31

    The intestinal tract maintains proper function by replacing aged cells with freshly produced cells that arise from a population of self-renewing intestinal stem cells (ISCs). In the mammalian intestine, ISC self renewal, amplification and differentiation take place along the crypt-villus axis, and are controlled by the Wnt and hedgehog (Hh) signalling pathways. However, little is known about the mechanisms that specify ISCs within the developing intestinal epithelium, or about the signalling centres that help maintain them in their self-renewing stem cell state. Here we show that in adult Drosophila melanogaster, ISCs of the posterior intestine (hindgut) are confined to an anterior narrow segment, which we name the hindgut proliferation zone (HPZ). Within the HPZ, self renewal of ISCs, as well as subsequent proliferation and differentiation of ISC descendants, are controlled by locally emanating Wingless (Wg, a Drosophila Wnt homologue) and Hh signals. The anteriorly restricted expression of Wg in the HPZ acts as a niche signal that maintains cells in a slow-cycling, self-renewing mode. As cells divide and move posteriorly away from the Wg source, they enter a phase of rapid proliferation. During this phase, Hh signal is required for exiting the cell cycle and the onset of differentiation. The HPZ, with its characteristic proliferation dynamics and signalling properties, is set up during the embryonic phase and becomes active in the larva, where it generates all adult hindgut cells including ISCs. The mechanism and genetic control of cell renewal in the Drosophila HPZ exhibits a large degree of similarity with what is seen in the mammalian intestine. Our analysis of the Drosophila HPZ provides an insight into the specification and control of stem cells, highlighting the way in which the spatial pattern of signals that promote self renewal, growth and differentiation is set up within a genetically tractable model system.

  11. Nephrotoxicity of high-dose ifosfamide/carboplatin/etoposide in adults undergoing autologous stem cell transplantation.

    PubMed

    Agaliotis, D P; Ballester, O F; Mattox, T; Hiemenz, J W; Fields, K K; Zorsky, P E; Goldstein, S C; Perkins, J B; Rosen, R M; Elfenbein, G J

    1997-11-01

    The objective of this study was to evaluate nephrotoxicity in adult patients treated with high-dose ifosfamide, carboplatin, and etoposide followed by autologous stem cell transplantation. We conducted a retrospective analysis of clinical and laboratory data from 131 patients with various malignancies who received treatment with escalating doses of ifosfamide, carboplatin, and etoposide followed by autologous stem cell transplantation as part of a phase I/II therapeutic trial. Abnormalities in glomerular filtration were evaluated by measuring peak creatinine levels and tubular dysfunction by the lowest recorded serum levels of potassium, magnesium, and bicarbonate, at different time periods after administration of ifosfamide, carboplatin, and etoposide, and after autologous stem cell transplantation. For the entire group of 131 patients, peak creatinine levels were > 1.5 mg/dL but < 3.0 mg/dL in 37% and levels were > 3.0 mg/dL in 11% at some time during their hospital stay. At the time of discharge, creatinine levels were 1.6 mg/dL to 3.0 mg/dL in 25% of patients and were > 3 mg/dL in 5%. Immediately after high-dose therapy, peak creatinine levels were significantly higher in patients receiving higher doses of ifosfamide compared to those receiving lower doses (P < 0.00001) and those receiving intermediate doses (P < 0.005). There was a dramatic decrease in serum bicarbonate, potassium, and magnesium levels immediately after chemotherapy, and they remained significantly decreased throughout the patient's hospital stay, despite massive replacement efforts (P ranging between < 0.008 and < 0.001). This is the largest adult population study documenting the incidence and severity of ifosfamide/carboplatin/etoposide-associated acute nephrotoxicity. Renal dysfunction was dose related and reversible in the majority of patients.

  12. UV light phototransduction depolarizes human melanocytes.

    PubMed

    Bellono, Nicholas W; Oancea, Elena

    2013-01-01

    Exposure of human skin to low doses of solar UV radiation (UVR) causes increased pigmentation, while chronic exposure is a powerful risk factor for skin cancers. The mechanisms mediating UVR detection in skin, however, remain poorly understood. Our recent studies revealed that UVR activates a retinal-dependent G protein-coupled signaling pathway in melanocytes. This phototransduction pathway leads to the activation of transient receptor potential A1 (TRPA1) ion channels, elevation of intracellular calcium (Ca( 2+)) and rapid increase in cellular melanin content. Here we report that physiological doses of solar-like UVR elicit a retinal-dependent membrane depolarization in human epidermal melanocytes. This transient depolarization correlates with delayed inactivation time of the UVR-evoked photocurrent and with sustained Ca( 2+) responses required for early melanin synthesis. Thus, the cellular depolarization induced by UVR phototransduction in melanocytes is likely to be a critical signaling mechanism necessary for the protective response represented by increased melanin content.

  13. Congenital Melanocytic Nevus Syndrome: A Case Series.

    PubMed

    Recio, A; Sánchez-Moya, A I; Félix, V; Campos, Y

    2017-01-19

    Congenital melanocytic nevus syndrome (CMNS) is the result of an abnormal proliferation of melanocytes in the skin and central nervous system caused by progenitor-cell mutations during embryonic development. Mutations in the NRAS gene have been detected in many of these cells. We present 5 cases of giant congenital melanocytic nevus, 3 of them associated with CMNS; NRAS gene mutation was studied in these 3 patients. Until a few years ago, surgery was the treatment of choice, but the results have proved unsatisfactory because aggressive interventions do not improve cosmetic appearance and only minimally reduce the risk of malignant change. In 2013, trametinib was approved for use in advanced melanoma associated with NRAS mutations. This drug, which acts on the intracellular RAS/RAF/MEK/pERK/MAPK cascade, could be useful in pediatric patients with CMNS. A better understanding of this disease will facilitate the development of new strategies.

  14. The Relationship of Psoriasis and Melanocytic Nevi

    PubMed Central

    Cengiz, Fatma Pelin; Emiroglu, Nazan; Bahali, Anil Gulsel; Ozkaya, Dilek Biyik; Su, Ozlem; Onsun, Nahide

    2016-01-01

    Background: There is limited data about the relationship between psoriasis and melanocytic lesions and melanoma. Immunologic pathways which were implicated in psoriasis induce a reduction in the number of melanocytic nevi. Aims and Objectives: To investigate the number of melanocytic nevi in psoriatic patients compared with controls and its relationship with disease severity and type of treatment. Methods: We performed a prospective study in 100 psoriatic patients and 100 controls. Clinical data were recorded for all participants. Results: As compared with controls, patients had overall fewer nevi congenital nevi. Among psoriatic patients, biologic agents and disease severity did not correlate with the number of nevi. Conclusions: Psoriatic patients have fewer nevi than controls. Frequency of nevi in psoriatic patients is not related to treatment and disease severity. PMID:27904187

  15. The ultrastructure of conjunctival melanocytic tumors.

    PubMed Central

    Jakobiec, F A

    1984-01-01

    The ultrastructure of conjunctival melanocytic lesions in 49 patients was evaluated to find significant differences between benign and malignant cells. The patients studied included 9 with benign epithelial (racial) melanosis, 2 with pigmented squamous cell papillomas, 16 with conjunctival nevi, 18 with primary acquired melanosis, and 11 with invasive nodules of malignant melanoma. In benign epithelial melanosis, dendritic melanocytes were situated along the basement membrane region of the conjunctival epithelium, with one basilar dendritic melanocyte lodged among every five or six basilar keratinocytes. The dendritic melanocytes extended arborizing cellular processes between the basilar and among the suprabasilar keratinocytes, which manifested considerable uptake of melanin granules into their cytoplasm. The benign dendritic melanocytes possessed nuclei with clumped heterochromatin at the nuclear membrane, small, tightly wound nucleoli, and large, elongated, fully melaninized melanin granules. In two patients with benign hyperplasia of the dendritic melanocytes, occasional dendritic melanocytes were located in a suprabasilar position, but were always separated from each other by keratinocytes or their processes. In the two black patients with benign pigmented squamous papillomas, the benign dendritic melanocytes were located hapharzardly at all levels of the acanthotic epithelium and not just along the basement membrane region. Melanin uptake by the proliferating keratinocytes was minimal. In benign melanocytic nevi of the conjunctiva, nevus cells within the intraepithelial junctional nests displayed a more rounded cellular configuration; short villi and broader cellular processes suggestive of abortive dendrites were found. The nuclear chromatin pattern was clumped at the nuclear membrane, but the nucleoli were somewhat larger than those of benign dendritic melanocytes in epithelial melanosis. The melanosomes were smaller and rounder than those in dendritic

  16. Congenital agminated melanocytic nevus - case report*

    PubMed Central

    da Rocha, Camila Roos Mariano; Grazziotin, Thaís Corsetti; Rey, Maria Carolina Widholzer; Luzzatto, Laura; Bonamigo, Renan Rangel

    2013-01-01

    Agminated nevus is a cluster group of melanocytic nevi confined to a localized area of the body. There are many pigmented lesions described in the literature as agminated, such as blue nevi, multiple lentigines and Spitz nevi, but only a few cases of congenital agminated melanocytic nevi have been described. We report a case of a male child who presented with congenital agminated nevi, emphasizing the importance of physical examination, dermoscopy, histopathological evaluation, differential diagnosis and follow up to rule out the possibility of dysplastic or malignant changes. PMID:24346910

  17. Sox9 modulates cell survival and adipogenic differentiation of multipotent adult rat mesenchymal stem cells.

    PubMed

    Stöckl, Sabine; Bauer, Richard J; Bosserhoff, Anja K; Göttl, Claudia; Grifka, Joachim; Grässel, Susanne

    2013-07-01

    Sox9 is a key transcription factor in early chondrogenesis with distinct roles in differentiation processes and during embryonic development. Here, we report that Sox9 modulates cell survival and contributes to the commitment of mesenchymal stem cells (MSC) to adipogenic or osteogenic differentiation lineages. We found that the Sox9 activity level affects the expression of the key transcription factor in adipogenic differentiation, C/EBPβ, and that cyclin D1 mediates the expression of the osteogenic marker osteocalcin in undifferentiated adult bone-marrow-derived rat MSC. Introducing a stable Sox9 knockdown into undifferentiated rat MSC resulted in a marked decrease in proliferation rate and an increase in apoptotic activity. This was linked to a profound upregulation of p21 and cyclin D1 gene and protein expression accompanied by an induction of caspase 3/7 activity and an inhibition of Bcl-2. We observed that Sox9 silencing provoked a delayed S-phase progression and an increased nuclear localization of p21. The protein stability of cyclin D1 was induced in the absence of Sox9 presumably as a function of altered p38 signalling. In addition, the major transcription factor for adipogenic differentiation, C/EBPβ, was repressed after silencing Sox9. The nearly complete absence of C/EBPβ protein as a result of increased destabilization of the C/EBPβ mRNA and the impact on osteocalcin gene expression and protein synthesis, suggests that a delicate balance of Sox9 level is not only imperative for proper chondrogenic differentiation of progenitor cells, but also affects the adipogenic and probably osteogenic differentiation pathways of MSC. Our results identified Sox9 as an important link between differentiation, proliferation and apoptosis in undifferentiated adult rat mesenchymal stem cells, emphasizing the importance of the delicate balance of a precisely regulated Sox9 activity in MSC not only for proper skeletal development during embryogenesis but probably also

  18. The Jak-STAT target Chinmo prevents sex transformation of adult stem cells in the Drosophila testis niche

    PubMed Central

    Ma, Qing; Wawersik, Matthew; Matunis, Erika L.

    2014-01-01

    Local signals maintain adult stem cells in many tissues. Whether the sexual identity of adult stem cells must also be maintained was not known. In the adult Drosophila testis niche, local Jak-STAT signaling promotes somatic cyst stem cell (CySC) renewal through several effectors, including the putative transcription factor Chronologically inappropriate morphogenesis (Chinmo). Here, we find that Chinmo also prevents feminization of CySCs. Chinmo promotes expression of the canonical male sex determination factor DoublesexM (DsxM) within CySCs and their progeny, and ectopic expression of DsxM in the CySC lineage partially rescues the chinmo sex transformation phenotype, placing Chinmo upstream of DsxM. The Dsx homologue DMRT1 prevents the male-to female conversion of differentiated somatic cells in the adult mammalian testis, but its regulation is not well understood. Our work indicates that sex maintenance occurs in adult somatic stem cells, and that this highly conserved process is governed by effectors of niche signals. PMID:25453558

  19. Notch1 is required for maintenance of the reservoir of adult hippocampal stem cells

    PubMed Central

    Ables, Jessica L.; DeCarolis, Nathan A.; Johnson, Madeleine A.; Rivera, Phillip D.; Gao, Zhengliang; Cooper, Don C.; Radtke, Freddy; Hsieh, Jenny; Eisch, Amelia J.

    2010-01-01

    Notch1 regulates neural stem cell (NSC) number during development, but its role in adult neurogenesis is unclear. We generated nestin-CreERT2/R26R-YFP/Notch1loxP/loxP (Notch1 iKO) mice to allow tamoxifen (TAM)-inducible elimination of Notch1 and concomitant expression of yellow fluorescent protein (YFP) in nestin-expressing Type-1 NSCs and their progeny in the adult hippocampal subgranular zone (SGZ). Consistent with previous research, YFP+ cells in all stages of neurogenesis were evident in the subgranular zone (SGZ) of wild type mice (WT; nestin-CreERT2/R26R-YFP/Notch1wt/wt) after tamoxifen (post-TAM), producing adult-generated YFP+ dentate gyrus neurons. Compared to WT littermates, Notch1 iKO mice had similar numbers of total SGZ YFP+ cells 13 and 30 days post-TAM but had significantly fewer SGZ YFP+ cells 60 and 90 days post-TAM. Significantly fewer YFP+ Type-1 NSCs and transiently-amplifying progenitors (TAPs) resulted in generation of fewer YFP+ granule neurons in Notch1 iKO mice. Strikingly, 30 days of running rescued this deficit, as the total YFP+ cell number in Notch iKO mice was equivalent to WT levels. This was even more notable given the persistent deficits in the Type-1 NSC and TAP reservoirs. Our data show that Notch1 signaling is required to maintain a reservoir of undifferentiated cells and ensure continuity of adult hippocampal neurogenesis, but that alternative Notch1- and Type-1 NSC-independent pathways compensate in response to physical activity. These data shed light on the complex relationship between Type-1 NSCs, adult neurogenesis, the neurogenic niche, and environmental stimuli. PMID:20685991

  20. Isolation of pluripotent neural crest-derived stem cells from adult human tissues by connexin-43 enrichment.

    PubMed

    Pelaez, Daniel; Huang, Chun-Yuh Charles; Cheung, Herman S

    2013-11-01

    Identification and isolation of pluripotent stem cells in adult tissues represent an important advancement in the fields of stem cell biology and regenerative medicine. For several years, research has been performed on the identification of biomarkers that can isolate stem cells residing in neural crest (NC)-derived adult tissues. The NC is considered a good model in stem cell biology as cells from it migrate extensively and contribute to the formation of diverse tissues in the body during organogenesis. Migration of these cells is modulated, in part, by gap junction communication among the cell sheets. Here we present a study in which, selection of connexin 43 (Cx43) expressing cells from human adult periodontal ligament yields a novel pluripotent stem cell population. Cx43⁺ periodontal ligament stem cells express pluripotency-associated transcription factors OCT4, Nanog, and Sox2, as well as NC-specific markers Sox10, p75, and Nestin. When injected in vivo into an immunodeficient mouse model, these cells were capable of generating teratomas with tissues from the three embryological germ layers: endoderm, mesoderm, and ectoderm. Furthermore, the cells formed mature structures of tissues normally arising from the NC during embryogenesis such as eccrine sweat glands of the human skin, muscle, neuronal tissues, cartilage, and bone. Immunohistochemical analysis confirmed the human origin of the neoplastic cells as well as the ectodermal and endodermal nature of some of the structures found in the tumors. These results suggest that Cx43 may be used as a biomarker to select and isolate the remnant NC pluripotent stem cells from adult human tissues arising from this embryological structure. The isolation of these cells through routine medical procedures such as wisdom teeth extraction further enhances their applicability to the regenerative medicine field.

  1. Existence of reserve quiescent stem cells in adults, from amphibians to humans.

    PubMed

    Young, H E

    2004-01-01

    Several theories have been proposed to explain the phenomenon of tissue restoration in amphibians and higher order animals. These theories include dedifferentiation of damaged tissues, transdifferentiation of lineage-committed stem cells, and activation of quiescent stem cells. Young and colleagues demonstrated that connective tissues throughout the body contain multiple populations of quiescent lineage-committed progenitor stem cells and lineage-uncommitted pluripotent stem cells. Subsequent cloning and cell sorting studies identified quiescent lineage-uncommitted pluripotent mesenchymal stem cells, capable of forming any mesodermal cell type, and pluripotent epiblastic-like stem cells, capable of forming any somatic cell type. Based on their studies, they propose at least 11 categories of quiescent reserve stem cells resident within postnatal animals, including humans. These categories are pluripotent epiblastic-like stem cells, pluripotent ectodermal stem cells, pluripotent epidermal stem cells, pluripotent neuronal stem cells, pluripotent neural crest stem cells, pluripotent mesenchymal (mesodermal) stem cells, pluripotent endodermal stem cells, multipotent progenitor stem cells, tripotent progenitor stem cells, bipotent progenitor stem cells, and unipotent progenitor stem cells. Thus, activation of quiescent reserve stem cells, i.e., lineage-committed progenitor stem cells and lineage-uncommitted pluripotent stem cells, resident within the connective tissues could provide for the continual maintenance and repair of the postnatal organism after birth.

  2. Regional Fluctuation in the Functional Consequence of LINE-1 Insertion in the Mitf Gene: The Black Spotting Phenotype Arisen from the Mitfmi-bw Mouse Lacking Melanocytes.

    PubMed

    Takeda, Kazuhisa; Hozumi, Hiroki; Ohba, Koji; Yamamoto, Hiroaki; Shibahara, Shigeki

    2016-01-01

    Microphthalmia-associated transcription factor (Mitf) is a key regulator for differentiation of melanoblasts, precursors to melanocytes. The mouse homozygous for the black-eyed white (Mitfmi-bw) allele is characterized by the white-coat color and deafness with black eyes due to the lack of melanocytes. The Mitfmi-bw allele carries LINE-1, a retrotransposable element, which results in the Mitf deficiency. Here, we have established the black spotting mouse that was spontaneously arisen from the homozygous Mitfmi-bw mouse lacking melanocytes. The black spotting mouse shows multiple black patches on the white coat, with age-related graying. Importantly, each black patch also contains hair follicles lacking melanocytes, whereas the white-coat area completely lacks melanocytes. RT-PCR analyses of the pigmented patches confirmed that the LINE-1 insertion is retained in the Mitf gene of the black spotting mouse, thereby excluding the possibility of the somatic reversion of the Mitfmi-bw allele. The immunohistochemical analysis revealed that the staining intensity for beta-catenin was noticeably lower in hair follicles lacking melanocytes of the homozygous Mitfmi-bw mouse and the black spotting mouse, compared to the control mouse. In contrast, the staining intensity for beta-catenin and cyclin D1 was higher in keratinocytes of the black spotting mouse, compared to keratinocytes of the control mouse and the Mitfmi-bw mouse. Moreover, the keratinocyte layer appears thicker in the Mitfmi-bw mouse, with the overexpression of Ki-67, a marker for cell proliferation. We also show that the presumptive black spots are formed by embryonic day 15.5. Thus, the black spotting mouse provides the unique model to explore the molecular basis for the survival and death of developing melanoblasts and melanocyte stem cells in the epidermis. These results indicate that follicular melanocytes are responsible for maintaining the epidermal homeostasis; namely, the present study has provided

  3. Wnts are dispensable for differentiation and self-renewal of adult murine hematopoietic stem cells

    PubMed Central

    Kabiri, Zahra; Numata, Akihiko; Kawasaki, Akira; Tenen, Daniel G.

    2015-01-01

    Wnt signaling controls early embryonic hematopoiesis and dysregulated β-catenin is implicated in leukemia. However, the role of Wnts and their source in adult hematopoiesis is still unclear, and is clinically important as upstream Wnt inhibitors enter clinical trials. We blocked Wnt secretion in hematopoietic lineages by targeting Porcn, a membrane-bound O-acyltransferase that is indispensable for the activity and secretion of all vertebrate Wnts. Surprisingly, deletion of Porcn in Rosa-CreERT2/PorcnDel, MX1-Cre/PorcnDel, and Vav-Cre/PorcnDel mice had no effects on proliferation, differentiation, or self-renewal of adult hematopoietic stem cells. Targeting Wnt secretion in the bone marrow niche by treatment with a PORCN inhibitor, C59, similarly had no effect on hematopoiesis. These results exclude a role for hematopoietic PORCN-dependent Wnts in adult hematopoiesis. Clinical use of upstream Wnt inhibitors is not likely to be limited by effects on hematopoiesis. PMID:26089398

  4. Brain Cancer Stem Cells in Adults and Children: Cell Biology and Therapeutic Implications.

    PubMed

    Abou-Antoun, Tamara J; Hale, James S; Lathia, Justin D; Dombrowski, Stephen M

    2017-04-03

    Brain tumors represent some of the most malignant cancers in both children and adults. Current treatment options target the majority of tumor cells but do not adequately target self-renewing cancer stem cells (CSCs). CSCs have been reported to resist the most aggressive radiation and chemotherapies, and give rise to recurrent, treatment-resistant secondary malignancies. With advancing technologies, we now have a better understanding of the genetic, epigenetic and molecular signatures and microenvironmental influences which are useful in distinguishing between distinctly different tumor subtypes. As a result, efforts are now underway to identify and target CSCs within various tumor subtypes based on this foundation. This review discusses progress in CSC biology as it relates to targeted therapies which may be uniquely different between pediatric and adult brain tumors. Studies to date suggest that pediatric brain tumors may benefit more from genetic and epigenetic targeted therapies, while combination treatments aimed specifically at multiple molecular pathways may be more effective in treating adult brain tumors which seem to have a greater propensity towards microenvironmental interactions. Ultimately, CSC targeting approaches in combination with current clinical therapies have the potential to be more effective owing to their ability to compromise CSCs maintenance and the mechanisms which underlie their highly aggressive and deadly nature.

  5. Role of allogeneic stem cell transplantation in adult patients with Ph-negative acute lymphoblastic leukemia.

    PubMed

    Dhédin, Nathalie; Huynh, Anne; Maury, Sébastien; Tabrizi, Reza; Beldjord, Kheira; Asnafi, Vahid; Thomas, Xavier; Chevallier, Patrice; Nguyen, Stéphanie; Coiteux, Valérie; Bourhis, Jean-Henri; Hichri, Yosr; Escoffre-Barbe, Martine; Reman, Oumedaly; Graux, Carlos; Chalandon, Yves; Blaise, Didier; Schanz, Urs; Lhéritier, Véronique; Cahn, Jean-Yves; Dombret, Hervé; Ifrah, Norbert

    2015-04-16

    Because a pediatric-inspired Group for Research on Adult Acute Lymphoblastic Leukemia (GRAALL) protocol yielded a markedly improved outcome in adults with Philadelphia chromosome-negative ALL, we aimed to reassess the role of allogeneic stem cell transplantation (SCT) in patients treated in the GRAALL-2003 and GRAALL-2005 trials. In all, 522 patients age 15 to 55 years old and presenting with at least 1 conventional high-risk factor were candidates for SCT in first complete remission. Among these, 282 (54%) received a transplant in first complete remission. At 3 years, posttransplant cumulative incidences of relapse, nonrelapse mortality, and relapse-free survival (RFS) were estimated at 19.5%, 15.5%, and 64.7%, respectively. Time-dependent analysis did not reveal a significant difference in RFS between SCT and no-SCT cohorts. However, SCT was associated with longer RFS in patients with postinduction minimal residual disease (MRD) ≥10(-3) (hazard ratio, 0.40) but not in good MRD responders. In B-cell precursor ALL, SCT also benefitted patients with focal IKZF1 gene deletion (hazard ratio, 0.42). This article shows that poor early MRD response, in contrast to conventional ALL risk factors, is an excellent tool to identify patients who may benefit from allogeneic SCT in the context of intensified adult ALL therapy. Trial GRAALL-2003 was registered at www.clinicaltrials.gov as #NCT00222027; GRAALL-2005 was registered as #NCT00327678.

  6. NGF induces adult stem Leydig cells to proliferate and differentiate during Leydig cell regeneration

    SciTech Connect

    Zhang, Lei; Wang, Huaxi; Yang, Yan; Liu, Hui; Zhang, Qihao; Xiang, Qi; Ge, Renshan; Su, Zhijian; Huang, Yadong

    2013-06-28

    Highlights: •Nerve growth factor has shown significant changes on mRNA levels during Adult Leydig cells regeneration. •We established the organ culture model of rat seminiferous tubules with ethane dimethyl sulphonate (EDS) treatment. •Nerve growth factor has shown proliferation and differentiation-promoting effects on Adult stem Leydig cells. •Nerve growth factor induces progenitor Leydig cells to proliferate and differentiate and immature Leydig cells to proliferate. -- Abstract: Nerve growth factor (NGF) has been reported to be involved in male reproductive physiology. However, few reports have described the activity of NGF during Leydig cell development. The objective of the present study was to examine the role of NGF during stem-Leydig-cell (SLC) regeneration. We investigated the effects of NGF on Leydig-cell (LC) regeneration by measuring mRNA levels in the adult rat testis after ethane dimethanesulfonate (EDS) treatment. Furthermore, we used the established organ culture model of rat seminiferous tubules to examine the regulation of NGF during SLC proliferation and differentiation using EdU staining, real-time PCR and western blotting. Progenitor Leydig cells (PLCs) and immature Leydig cells (ILCs) were also used to investigate the effects of NGF on LCs at different developmental stages. NGF mRNA levels changed significantly during Leydig-cell regeneration in vivo. In vitro, NGF significantly promoted the proliferation of stem Leydig cells and also induced steroidogenic enzyme gene expression and 3β-HSD protein expression. The data from PLCs and ILCs showed that NGF could increase Cyclin D1 and Hsd 17b3 mRNA levels in PLCs and Cyclin D1 mRNA levels in ILCs. These results indicate that NGF may play an important role during LC regeneration by regulating the proliferation and differentiation of LCs at different developmental stages, from SLCs to PLCs and from PLCs to ILCs. The discovery of this effect of NGF on Leydig cells will provide useful

  7. Biological characterization of human fibroblast-derived mitogenic factors for human melanocytes.

    PubMed Central

    Imokawa, G; Yada, Y; Morisaki, N; Kimura, M

    1998-01-01

    To clarify the paracrine linkage between human fibroblasts and melanocytes in cutaneous pigmentation, we studied the effects of human fibroblast-derived factors on the proliferation of human melanocytes. In medium conditioned for 4 days with human fibroblast culture, factors were produced that markedly stimulated DNA synthesis of human melanocytes. The stimulatory effect was higher in medium conditioned with fibroblasts from aged skin than in medium conditioned with fibroblasts from young skin, and was interrupted by inhibitors of tyrosine kinase, such as tyrphostin, genistein and herbimycin, but not by inhibitors of protein kinases C and A, such as H-7 and phloretin. The conditioned medium was also capable of activating mitogen-activated protein kinase of human melanocytes, with old fibroblasts being more effective than young ones. Analysis of factors released into the conditioned medium revealed that levels of hepatocyte growth factor (HGF) and stem cell factor (SCF) were increased in old-fibroblast-conditioned medium compared with young-fibroblast-conditioned medium. In contrast, levels of basic fibroblast growth factor (bFGF) were similar in both media. When the conditioned medium was treated with HGF antibody with or without SCF antibody, the increase in DNA synthesis by human melanocytes was decreased to 20% of the elevated level, whereas antibodies to bFGF had no effect. Analysis of the medium conditioned for 4 days after cytokine application demonstrated that, of the cytokines tested, interleukin 1alpha and tumour necrosis factor alpha are highly effective in stimulating HGF secretion by old fibroblasts. HGF and SCF, but not bFGF, were markedly increased in culture medium in the presence of IL-1alpha, and this stimulatory effect was confined to young human fibroblasts. These findings suggest that SCF and HGF derived from human fibroblasts may play a part in regulating cutaneous pigmentation during inflammation and aging. PMID:9494091

  8. Postnatal lineage mapping of follicular melanocytes with the Tyr::CreER(T) (2) transgene.

    PubMed

    Harris, Melissa L; Pavan, William J

    2013-03-01

    One of the main advantages of using inducible and conditional transgenes to study pigment cell biology is that they allow for genetic manipulation within melanocytes after roles in general neural crest or melanoblast development have been fulfilled. Specifically, we focus here on the ability of the Tyr::CreER(T) (2) transgenic line to alter genes within follicular melanocytes postnatally. Using the Gt(ROSA)26Sor(tm1sor) reporter allele, we present in detail the expression and activity of Tyr::CreER(T) (2) when induced during hair morphogenesis and adult hair cycling. We find that despite similarities in expression pattern to endogenous TYR, Tyr::CreER(T) (2) is effective at targeting both undifferentiated and differentiated melanocytes within the hair follicle. We also find that Tyr::CreER(T) (2) provides the highest levels of recombination when induced during the early phases of hair growth. In conclusion, the descriptions provided here will guide future analyses of gene function within the melanocyte system of the hair follicle when using this Tyr::CreER(T) (2) transgene.

  9. CD133 is not present on neurogenic astrocytes in the adult subventricular zone, but on embryonic neural stem cells, ependymal cells, and glioblastoma cells.

    PubMed

    Pfenninger, Cosima V; Roschupkina, Teona; Hertwig, Falk; Kottwitz, Denise; Englund, Elisabet; Bengzon, Johan; Jacobsen, Sten Eirik; Nuber, Ulrike A

    2007-06-15

    Human brain tumor stem cells have been enriched using antibodies against the surface protein CD133. An antibody recognizing CD133 also served to isolate normal neural stem cells from fetal human brain, suggesting a possible lineage relationship between normal neural and brain tumor stem cells. Whether CD133-positive brain tumor stem cells can be derived from CD133-positive neural stem or progenitor cells still requires direct experimental evidence, and an important step toward such investigations is the identification and characterization of normal CD133-presenting cells in neurogenic regions of the embryonic and adult brain. Here, we present evidence that CD133 is a marker for embryonic neural stem cells, an intermediate radial glial/ependymal cell type in the early postnatal stage, and for ependymal cells in the adult brain, but not for neurogenic astrocytes in the adult subventricular zone. Our findings suggest two principal possibilities for the origin of brain tumor stem cells: a derivation from CD133-expressing cells, which are normally not present in the adult brain (embryonic neural stem cells and an early postnatal intermediate radial glial/ependymal cell type), or from CD133-positive ependymal cells in the adult brain, which are, however, generally regarded as postmitotic. Alternatively, brain tumor stem cells could be derived from proliferative but CD133-negative neurogenic astrocytes in the adult brain. In the latter case, brain tumor development would involve the production of CD133.

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

    PubMed Central

    Beksac, Meral

    2016-01-01

    As cord blood (CB) enables rapid access and tolerance to HLA mismatches, a number of unrelated CB transplants have reached 30,000. Such transplant activity has been the result of international accreditation programs maintaining highly qualified cord blood units (CBUs) reaching more than 600,000 CBUs stored worldwide. Efforts to increase stem cell content or engraftment rate of the graft by ex vivo expansion, modulation by molecules such as fucose, prostaglandin E2 derivative, complement CD26 inhibitors, or CXCR4/CXCL12 axis have been able to accelerate engraftment speed and rate. Furthermore, introduction of reduced intensity conditioning protocols, better HLA matching, and recognition of the importance of HLA-C have improved CB transplants success by decreasing transplant-related mortality. CB progenitor/stem cell content has been compared with adult stem cells revealing higher long-term repopulating capacity compared to bone marrow–mesenchymal stromal cells and lesser oncogenic potential than progenitor-induced stem cells. This chapter summarizes the advantages and disadvantages of CB compared to adult stem cells within the context of stem cell biology and transplantation. PMID:26793711

  11. Adult stem cell theory of the multi-stage, multi-mechanism theory of carcinogenesis: role of inflammation on the promotion of initiated stem cells.

    PubMed

    Trosko, James E; Tai, Mei-Hui

    2006-01-01

    Inflammation, induced by microbial agents, radiation, endogenous or exogenous chemicals, has been associated with chronic diseases, including cancer. Since carcinogenesis has been characterized as consisting of the 'initiation', 'promotion' and 'progression' phases, the inflammatory process could affect any or all three phases. The stem cell theory of carcinogenesis has been given a revival, in that isolated human adult stem cells have been isolated and shown to be 'targets' for neoplastic transformation. Oct4, a transcription factor, has been associated with adult stem cells, as well as their immortalized and tumorigenic derivatives, but not with the normal differentiated daughters. These data are consistent with the stem cell theory of carcinogenesis. In addition, Gap Junctional Intercellular Communication (GJIC) seems to play a major role in cell growth. Inhibition of GJIC by non-genotoxic chemicals or various oncogenes seems to be the mechanism for the tumor promotion and progression phases of carcinogenesis. Many of the toxins, synthetic non-genotoxicants, and endogenous inflammatory factors have been shown to inhibit GJIC and act as tumor promoters. The inhibition of GJIC might be the mechanism by which the inflammatory process affects cancer and that to intervene during tumor promotion with anti-inflammatory factors might be the most efficacious anti-cancer strategy.

  12. The usefulness of c-Kit in the immunohistochemical assessment of melanocytic lesions

    PubMed Central

    Pilloni, L.; Bianco, P.; Difelice, E.; Cabras, S.; Castellanos, M.E.; Atzori, L.; Ferreli, C.; Mulas, P.; Nemolato, S.; Faa, G.

    2011-01-01

    C-Kit (CD117), the receptor for the stem cell factor, a growth factor for melanocyte migration and proliferation, has shown differential immunostaining in various benign and malignant melanocytic lesions. The purpose of this study is to compare c-Kit immunostaining in benign nevi and in primary and metastatic malignant melanomas, to determine whether c-Kit can aid in the differential diagnosis of these lesions. c-Kit immunostaining was performed in 60 cases of pigmented lesions, including 39 benign nevi (5 blue nevi, 5 intra-dermal nevi, 3 junctional nevi, 15 cases of primary compound nevus, 11 cases of Spitz nevus), 18 cases of primary malignant melanoma and 3 cases of metastatic melanoma. The vast majority of nevi and melanomas examined in this study were positive for c-Kit, with minimal differences between benign and malignant lesions. C-Kit cytoplasmatic immunoreactivity in the intraepidermal proliferating nevus cells, was detected in benign pigmented lesions as well as in malignant melanoma, increasing with the age of patients (P=0.007) in both groups. The patient’s age at presentation appeared to be the variable able to cluster benign and malignant pigmented lesions. The percentage of c-Kit positive intraepidermal nevus cells was better associated with age despite other variables (P=0.014). The intensity and percentage of c-Kit positivity in the proliferating nevus cells in the dermis was significantly increased in malignant melanocytic lesions (P=0.015 and P=0.008) compared to benign lesions (compound melanocytic nevi, Spitz nevi, intradermal nevi, blue nevi). Immunostaning for c-Kit in metastatic melanomas was negative. Interestingly in two cases of melanoma occurring on a pre-existent nevus, the melanoma tumor cells showed strong cytoplasmatic and membranous positivity for c-kit, in contrast with the absence of any immunoreactivity in pre-existent intradermal nevus cells. C-Kit does not appear to be a strong immunohistochemical marker for distinguishing

  13. Fetal and adult hematopoietic stem cells give rise to distinct T cell lineages in humans.

    PubMed

    Mold, Jeff E; Venkatasubrahmanyam, Shivkumar; Burt, Trevor D; Michaëlsson, Jakob; Rivera, Jose M; Galkina, Sofiya A; Weinberg, Kenneth; Stoddart, Cheryl A; McCune, Joseph M

    2010-12-17

    Although the mammalian immune system is generally thought to develop in a linear fashion, findings in avian and murine species argue instead for the developmentally ordered appearance (or "layering") of distinct hematopoietic stem cells (HSCs) that give rise to distinct lymphocyte lineages at different stages of development. Here we provide evidence of an analogous layered immune system in humans. Our results suggest that fetal and adult T cells are distinct populations that arise from different populations of HSCs that are present at different stages of development. We also provide evidence that the fetal T cell lineage is biased toward immune tolerance. These observations offer a mechanistic explanation for the tolerogenic properties of the developing fetus and for variable degrees of immune responsiveness at birth.

  14. Pten is necessary for the quiescence and maintenance of adult muscle stem cells

    PubMed Central

    Yue, Feng; Bi, Pengpeng; Wang, Chao; Shan, Tizhong; Nie, Yaohui; Ratliff, Timothy L.; Gavin, Timothy P.; Kuang, Shihuan

    2017-01-01

    Satellite cells (SCs) are myogenic stem cells required for regeneration of adult skeletal muscles. A proper balance among quiescence, activation and differentiation is essential for long-term maintenance of SCs and their regenerative function. Here we show a function of Pten (phosphatase and tensin homologue) in quiescent SCs. Deletion of Pten in quiescent SCs leads to their spontaneous activation and premature differentiation without proliferation, resulting in depletion of SC pool and regenerative failure. However, prior to depletion, Pten-null activated SCs can transiently proliferate upon injury and regenerate injured muscles, but continually decline during regeneration, suggesting an inability to return to quiescence. Mechanistically, Pten deletion increases Akt phosphorylation, which induces cytoplasmic translocation of FoxO1 and suppression of Notch signalling. Accordingly, constitutive activation of Notch1 prevents SC depletion despite Pten deletion. Our findings delineate a critical function of Pten in maintaining SC quiescence and reveal an interaction between Pten and Notch signalling. PMID:28094257

  15. Adult Vascular Wall Resident Multipotent Vascular Stem Cells, Matrix Metalloproteinases, and Arterial Aneurysms

    PubMed Central

    Amato, Bruno; Compagna, Rita; Amato, Maurizio; Grande, Raffaele; Butrico, Lucia; Rossi, Alessio; Naso, Agostino; Ruggiero, Michele; de Franciscis, Stefano

    2015-01-01

    Evidences have shown the presence of multipotent stem cells (SCs) at sites of arterial aneurysms: they can differentiate into smooth muscle cells (SMCs) and are activated after residing in a quiescent state in the vascular wall. Recent studies have implicated the role of matrix metalloproteinases in the pathogenesis of arterial aneurysms: in fact the increased synthesis of MMPs by arterial SMCs is thought to be a pivotal mechanism in aneurysm formation. The factors and signaling pathways involved in regulating wall resident SC recruitment, survival, proliferation, growth factor production, and differentiation may be also related to selective expression of different MMPs. This review explores the relationship between adult vascular wall resident multipotent vascular SCs, MMPs, and arterial aneurysms. PMID:25866513

  16. Insights from a chimpanzee adipose stromal cell population: opportunities for adult stem cells to expand primate functional genomics.

    PubMed

    Pfefferle, Lisa W; Wray, Gregory A

    2013-01-01

    Comparisons between humans and chimpanzees are essential for understanding traits unique to each species. However, linking important phenotypic differences to underlying molecular changes is often challenging. The ability to generate, differentiate, and profile adult stem cells provides a powerful but underutilized opportunity to investigate the molecular basis for trait differences between species within specific cell types and in a controlled environment. Here, we characterize adipose stromal cells (ASCs) from Clint, the chimpanzee whose genome was first sequenced. Using imaging and RNA-Seq, we compare the chimpanzee ASCs with three comparable human cell lines. Consistent with previous studies on ASCs in humans, the chimpanzee cells have fibroblast-like morphology and express genes encoding components of the extracellular matrix at high levels. Differentially expressed genes are enriched for distinct functional classes between species: immunity and protein processing are higher in chimpanzees, whereas cell cycle and DNA processing are higher in humans. Although hesitant to draw definitive conclusions from these data given the limited sample size, we wish to stress the opportunities that adult stem cells offer for studying primate evolution. In particular, adult stem cells provide a powerful means to investigate the profound disease susceptibilities unique to humans and a promising tool for conservation efforts with nonhuman primates. By allowing for experimental perturbations in relevant cell types, adult stem cells promise to complement classic comparative primate genomics based on in vivo sampling.

  17. Complementary epistasis involving Sr12 explains adult plant resistance to stem rust in Thatcher wheat (Triticum aestivum L.)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Adult plant resistance (APR) in wheat (Triticum aestivum L.) to stem rust, caused by Puccinia graminis f. sp. tritici, is desirable because this resistance can be race non-specific. Resistance derived from cultivar Thatcher can confer high levels of APR to the virulent P. graminis f. sp. tritici rac...

  18. Clear-cell melanocytic lesions with balloon-cell and sebocyte-like melanocytes: a unifying concept.

    PubMed

    Kazlouskaya, Viktoryia; Guo, Ying; Maia-Cohen, Sandra; Mones, Joan

    2014-05-01

    Melanocytes may assume unique shapes and sizes but rarely have clear cytoplasm. We studied 28 melanocytic lesions that contained clear-cell melanocytes of the balloon-cell and sebocyte-like types. Clear-cell melanocytes were found more commonly in females (64%) than in males (36%), with predominance in females younger than 50 years (79%) and predominance in males older than 50 years (67%). They were distributed evenly throughout the body but were not found on acral sites. Clear-cell melanocytes were most prevalent in congenital nevi (18 or 72%) but were also found in 5 Clark nevi, 2 Meischer nevi, 1 Unna nevus, 1 atypical intra-epidermal proliferation, and 1 melanoma. The clear cells were distributed diffusely in 86% of the lesions and focally in 14%. The overall percentage of clear-cell melanocytes was 56%. The percentage of balloon cells was 57% and sebocyte-like melanocytes 32%. Clear cells with morphologic features of both balloon cells and sebocyte-like melanocytes, that is, intermediate cells, were present in all lesions with an overall percentage of 12%. The presence of melanocytes of both the balloon-cell and sebocyte-like types and the finding of clear-cell melanocytes with intermediate features in all lesions lends support to the theory that balloon-cell and sebocyte-like melanocytes may represent morphologic expressions of the same alteration in melanogenesis.

  19. Plasmid-Based Generation of Induced Neural Stem Cells from Adult Human Fibroblasts

    PubMed Central

    Capetian, Philipp; Azmitia, Luis; Pauly, Martje G.; Krajka, Victor; Stengel, Felix; Bernhardi, Eva-Maria; Klett, Mariana; Meier, Britta; Seibler, Philip; Stanslowsky, Nancy; Moser, Andreas; Knopp, Andreas; Gillessen-Kaesbach, Gabriele; Nikkhah, Guido; Wegner, Florian; Döbrössy, Máté; Klein, Christine

    2016-01-01

    Direct reprogramming from somatic to neural cell types has become an alternative to induced pluripotent stem cells. Most protocols employ viral expression systems, posing the risk of random genomic integration. Recent developments led to plasmid-based protocols, lowering this risk. However, these protocols either relied on continuous presence of a variety of small molecules or were only able to reprogram murine cells. We therefore established a reprogramming protocol based on vectors containing the Epstein-Barr virus (EBV)-derived oriP/EBNA1 as well as the defined expression factors Oct3/4, Sox2, Klf4, L-myc, Lin28, and a small hairpin directed against p53. We employed a defined neural medium in combination with the neurotrophins bFGF, EGF and FGF4 for cultivation without the addition of small molecules. After reprogramming, cells demonstrated a temporary increase in the expression of endogenous Oct3/4. We obtained induced neural stem cells (iNSC) 30 days after transfection. In contrast to previous results, plasmid vectors as well as a residual expression of reprogramming factors remained detectable in all cell lines. Cells showed a robust differentiation into neuronal (72%) and glial cells (9% astrocytes, 6% oligodendrocytes). Despite the temporary increase of pluripotency-associated Oct3/4 expression during reprogramming, we did not detect pluripotent stem cells or non-neural cells in culture (except occasional residual fibroblasts). Neurons showed electrical activity and functional glutamatergic synapses. Our results demonstrate that reprogramming adult human fibroblasts to iNSC by plasmid vectors and basic neural medium without small molecules is possible and feasible. However, a full set of pluripotency-associated transcription factors may indeed result in the acquisition of a transient (at least partial) pluripotent intermediate during reprogramming. In contrast to previous reports, the EBV-based plasmid system remained present and active inside the cells at

  20. Clone-forming activity of embryonal stem hemopoietic cells after transplantation to newborn or adult sublethally irradiated mice.

    PubMed

    Drize, N I; Chertkov, I L

    2000-07-01

    Hemopoietic activity of stem hemopoietic cells from the liver of embryos was studied at different terms of intrauterine development. The fate of individual clones of hemopoietic cells marked by human adenosine deaminase gene was followed up in sublethally irradiated or newborn recipients. The efficiency of marker gene incorporation in primitive stem hemopoietic cells from the liver of 12-, 13-, and 17-day embryos was not high. Gene transfer was performed without cell prestimulation to division, and hence, these data show that primitive stem cells proliferate even in 17-day embryos. Cells from embryonal liver in all terms maintain hemopoiesis both in newborn and adult microenvironment, hemopoiesis being realized according to the clonal succession model, i. e. in the some way after transplantation of the bone marrow from adult mice.

  1. Immunomodulatory properties of human adult and fetal multipotent mesenchymal stem cells.

    PubMed

    Chen, Pei-Min; Yen, Men-Luh; Liu, Ko-Jiunn; Sytwu, Huey-Kang; Yen, B-Linju

    2011-07-18

    In recent years, a large number of studies have contributed to our understanding of the immunomodulatory mechanisms used by multipotent mesenchymal stem cells (MSCs). Initially isolated from the bone marrow (BM), MSCs have been found in many tissues but the strong immunomodulatory properties are best studied in BM MSCs. The immunomodulatory effects of BM MSCs are wide, extending to T lymphocytes and dendritic cells, and are therapeutically useful for treatment of immune-related diseases including graft-versus-host disease as well as possibly autoimmune diseases. However, BM MSCs are very rare cells and require an invasive procedure for procurement. Recently, MSCs have also been found in fetal-stage embryo-proper and extra-embryonic tissues, and these human fetal MSCs (F-MSCs) have a higher proliferative profile, and are capable of multilineage differentiation as well as exert strong immunomodulatory effects. As such, these F-MSCs can be viewed as alternative sources of MSCs. We review here the current understanding of the mechanisms behind the immunomodulatory properties of BM MSCs and F-MSCs. An increase in our understanding of MSC suppressor mechanisms will offer insights for prevalent clinical use of these versatile adult stem cells in the near future.

  2. Clinical trial perspective for adult and juvenile Huntington's disease using genetically-engineered mesenchymal stem cells.

    PubMed

    Deng, Peter; Torrest, Audrey; Pollock, Kari; Dahlenburg, Heather; Annett, Geralyn; Nolta, Jan A; Fink, Kyle D

    2016-05-01

    Progress to date from our group and others indicate that using genetically-engineered mesenchymal stem cells (MSC) to secrete brain-derived neurotrophic factor (BDNF) supports our plan to submit an Investigational New Drug application to the Food and Drug Administration for the future planned Phase 1 safety and tolerability trial of MSC/BDNF in patients with Huntington's disease (HD). There are also potential applications of this approach beyond HD. Our biological delivery system for BDNF sets the precedent for adult stem cell therapy in the brain and could potentially be modified for other neurodegenerative disorders such as amyotrophic lateral sclerosis (ALS), spinocerebellar ataxia (SCA), Alzheimer's disease, and some forms of Parkinson's disease. The MSC/BDNF product could also be considered for studies of regeneration in traumatic brain injury, spinal cord and peripheral nerve injury. This work also provides a platform for our future gene editing studies, since we will again use MSCs to deliver the needed molecules into the central nervous system.

  3. Adult neural stem cells from the subventricular zone: a review of the neurosphere assay.

    PubMed

    Gil-Perotín, Sara; Duran-Moreno, María; Cebrián-Silla, Arantxa; Ramírez, Mónica; García-Belda, Paula; García-Verdugo, José Manuel

    2013-09-01

    The possibility of obtaining large numbers of cells with potential to become functional neurons implies a great advance in regenerative medicine. A source of cells for therapy is the subventricular zone (SVZ) where adult neural stem cells (NSCs) retain the ability to proliferate, self-renew, and differentiate into several mature cell types. The neurosphere assay, a method to isolate, maintain, and expand these cells has been extensively utilized by research groups to analyze the biological properties of aNSCs and to graft into injured brains from animal models. In this review we briefly describe the neurosphere assay and its limitations, the methods to optimize culture conditions, the identity and the morphology of aNSC-derived neurospheres (including new ultrastructural data). The controversy regarding the identity and "stemness" of cells within the neurosphere is revised. The fine morphology of neurospheres, described thoroughly, allows for phenotypical characterization of cells in the neurospheres and may reveal slight changes that indirectly inform about cell integrity, cell damage, or oncogenic transformation. Along this review we largely highlight the critical points that researchers have to keep in mind before extrapolating results or translating experimental transplantation of neurosphere-derived cells to the clinical setting.

  4. Hhex is Required at Multiple Stages of Adult Hematopoietic Stem and Progenitor Cell Differentiation

    PubMed Central

    Goodings, Charnise; Smith, Elizabeth; Mathias, Elizabeth; Elliott, Natalina; Cleveland, Susan M.; Tripathi, Rati M.; Layer, Justin H.; Chen, Xi; Guo, Yan; Shyr, Yu; Hamid, Rizwan; Du, Yang; Davé, Utpal P.

    2015-01-01

    Hhex encodes a homeodomain transcription factor that is widely expressed in hematopoietic stem and progenitor cell populations. Its enforced expression induces T-cell leukemia and we have implicated it as an important oncogene in early T-cell precursor leukemias where it is immediately downstream of an LMO2-associated protein complex. Conventional Hhex knockouts cause embryonic lethality precluding analysis of adult hematopoiesis. Thus, we induced highly efficient conditional knockout (cKO) using vav-Cre transgenic mice. Hhex cKO mice were viable and born at normal litter sizes. At steady state, we observed a defect in B-cell development that we localized to the earliest B-cell precursor, the pro-B-cell stage. Most remarkably, bone marrow transplantation using Hhex cKO donor cells revealed a more profound defect in all hematopoietic lineages. In contrast, sublethal irradiation resulted in normal myeloid cell repopulation of the bone marrow but markedly impaired repopulation of T- and B-cell compartments. We noted that Hhex cKO stem and progenitor cell populations were skewed in their distribution and showed enhanced proliferation compared to WT cells. Our results implicate Hhex in the maintenance of LT-HSCs and in lineage allocation from multipotent progenitors especially in stress hematopoiesis. PMID:25968920

  5. Clinical trial perspective for adult and juvenile Huntington's disease using genetically-engineered mesenchymal stem cells

    PubMed Central

    Deng, Peter; Torrest, Audrey; Pollock, Kari; Dahlenburg, Heather; Annett, Geralyn; Nolta, Jan A.; Fink, Kyle D.

    2016-01-01

    Progress to date from our group and others indicate that using genetically-engineered mesenchymal stem cells (MSC) to secrete brain-derived neurotrophic factor (BDNF) supports our plan to submit an Investigational New Drug application to the Food and Drug Administration for the future planned Phase 1 safety and tolerability trial of MSC/BDNF in patients with Huntington's disease (HD). There are also potential applications of this approach beyond HD. Our biological delivery system for BDNF sets the precedent for adult stem cell therapy in the brain and could potentially be modified for other neurodegenerative disorders such as amyotrophic lateral sclerosis (ALS), spinocerebellar ataxia (SCA), Alzheimer's disease, and some forms of Parkinson's disease. The MSC/BDNF product could also be considered for studies of regeneration in traumatic brain injury, spinal cord and peripheral nerve injury. This work also provides a platform for our future gene editing studies, since we will again use MSCs to deliver the needed molecules into the central nervous system. PMID:27335539

  6. Transcription levels of sirtuin family in neural stem cells and brain tissues of adult mice.

    PubMed

    Wang, H F; Li, Q; Feng, R L; Wen, T Q

    2012-09-10

    Neural stem cells (NSCs) has been used as a well-known model to investigate apoptosis, differentiation, maintenance of stem cells status, and therapy of neurological disease. The C17.2 NSCs line was produced after v-myc transformation of neural progenitor from mouse cerebellar cortex. Sirtuin family plays important roles involved in neuronal differentiation, genomic stability, lifespan, cell survival. However, little is known about gene expression variation of sirtuin family in C17.2 NSCs, primary NSCs, and different brain tissues in adult mice. Here, we confirmed that the mRNA expression levels of sirt2, 3, 4, 5, and 7 in E14.5 NSCs were significantly higher than in C17.2 NSCs, whereas that sirt 6 displayed an opposing mode. Moreover, a higher mRNA level of sirtuin family was observed in the adult mouse brain compared to C17.2 NSCs. In addition, histone deacetylase (HDAC) inhibitors nicotinamide and Trichostatin A (TSA) were used to explore differential changes at the transcriptional level of sirtuins. Results indicated that the expression of sirt1, sirt5 and sirt6 was significant downregulated by nicotinamide treatment. Whereas, a significant downregulation in sirt1 and sirt3 and a significant upregulation in sirt2, sirt4, sirt6, and sirt7 were observed in the treatment of TSA. Thus our studies indicate different sirtuin mRNA expression profiles between C17.2 NSCs, E14.5 NSCs and brain tissues, suggesting the transcriptional regulation of sirtuin family could be mediated by different histone acetylation.

  7. Wnt Signaling Regulates Airway Epithelial Stem Cells in Adult Murine Submucosal Glands.

    PubMed

    Lynch, Thomas J; Anderson, Preston J; Xie, Weiliang; Crooke, Adrianne K; Liu, Xiaoming; Tyler, Scott R; Luo, Meihui; Kusner, David M; Zhang, Yulong; Neff, Traci; Burnette, Daniel C; Walters, Katherine S; Goodheart, Michael J; Parekh, Kalpaj R; Engelhardt, John F

    2016-06-24

    Wnt signaling is required for lineage commitment of glandular stem cells (SCs) during tracheal submucosal gland (SMG) morphogenesis from the surface airway epithelium (SAE). Whether similar Wnt-dependent processes coordinate SC expansion in adult SMGs following airway injury remains unknown. We found that two Wnt-reporters in mice (BAT-gal and TCF/Lef:H2B-GFP) are coexpressed in actively cycling SCs of primordial glandular placodes and in a small subset of adult SMG progenitor cells that enter the cell cycle 24 hours following airway injury. At homeostasis, these Wnt reporters showed nonoverlapping cellular patterns of expression in the SAE and SMGs. Following tracheal injury, proliferation was accompanied by dynamic changes in Wnt-reporter activity and the analysis of 56 Wnt-related signaling genes revealed unique temporal changes in expression within proximal (gland-containing) and distal (gland-free) portions of the trachea. Wnt stimulation in vivo and in vitro promoted epithelial proliferation in both SMGs and the SAE. Interestingly, slowly cycling nucleotide label-retaining cells (LRCs) of SMGs were spatially positioned near clusters of BAT-gal positive serous tubules. Isolation and culture of tet-inducible H2B-GFP LRCs demonstrated that SMG LRCs were more proliferative than SAE LRCs and culture expanded SMG-derived progenitor cells outcompeted SAE-derived progenitors in regeneration of tracheal xenograft epithelium using a clonal analysis competition assay. SMG-derived progenitors were also multipotent for cell types in the SAE and formed gland-like structures in xenografts. These studies demonstrate the importance of Wnt signals in modulating SC phenotypes within tracheal niches and provide new insight into phenotypic differences of SMG and SAE SCs. Stem Cells 2016.

  8. Effect of mesenchymal stem cells on induced skeletal muscle chemodenervation atrophy in adult male albino rats.

    PubMed

    Shehata, Azza S; Al-Ghonemy, Nabila M; Ahmed, Samah M; Mohamed, Samar R

    2017-04-01

    The present research was conducted to evaluate the effect of bone marrow derived mesenchymal stem cells (BM-MSCs) as a potential therapeutic tool for improvement of skeletal muscle recovery after induced chemodenervation atrophy by repeated local injection of botulinum toxin-A in the right tibialis anterior muscle of adult male albino rats. Forty five adult Wistar male albino rats were classified into control and experimental groups. Experimental group was further subdivided into 3 equal subgroups; induced atrophy, BM-MSCs treated and recovery groups. Biochemical analysis of serum LDH, CK and Real-time PCR for Bcl-2, caspase 3 and caspase 9 was measured. Skeletal muscle sections were stained with H and E, Mallory trichrome, and Immunohistochemical reaction for Bax and CD34. Improvement in the skeletal muscle histological structure was noticed in BM-MSCs treated group, however, in the recovery group, some sections showed apparent transverse striations and others still affected. Immunohistochemical reaction of Bax protein showed strong positive immunoreaction in the cytoplasm of muscle fibers in the induced atrophy group. BM-MSCs treated group showed weak positive reaction while the recovery group showed moderate reaction in the cytoplasm of muscle fibers. Immunohistochemical reaction for CD34 revealed occasional positive CD34 stained cells in the induced atrophy group. In BM-MSCs treated group, multiple positive CD34 stained cells were detected. However, recovery group showed some positive CD34 stained cells at the periphery of the muscle fibers. Marked improvement in the regenerative capacity of skeletal muscles after BM-MSCs therapy. Hence, stem cell therapy provides a new hope for patients suffering from myopathies and severe injuries.

  9. Developing Mentors: Adult participation, practices, and learning in an out-of-school time STEM program

    NASA Astrophysics Data System (ADS)

    Scipio, Deana Aeolani

    This dissertation examines learning within an out-of-school time (OST) Science, Technology, Engineering, and Mathematics (STEM) broadening participation program. The dissertation includes an introduction, three empirical chapters (written as individual articles), and a conclusion. The dissertation context is a chemical oceanography OST program for middle school students called Project COOL---Chemical Oceanography Outside the Lab. The program was a collaboration between middle school OST programming, a learning sciences research laboratory, and a chemical oceanography laboratory. Both labs were located at a research-based university in the Pacific Northwest of the United States. Participants include 34 youth, 12 undergraduates, and five professional scientists. The dissertation data corpus includes six years of ethnographic field notes across three field sites, 400 hours of video and audio recordings, 40 hours of semi-structured interviews, and more than 100 participant generated artifacts. Analysis methods include comparative case analysis, cognitive mapping, semiotic cluster analysis, video interaction analysis, and discourse analysis. The first empirical article focuses on synthesizing productive programmatic features from four years of design-based research.. The second article is a comparative case study of three STEM mentors from non-dominant communities in the 2011 COOL OST Program. The third article is a comparative case study of undergraduates learning to be mentors in the 2014 COOL OST Program. Findings introduce Deep Hanging as a theory of learning in practice. Deep Hanging entails authentic tasks in rich contexts, providing access, capitalizing on opportunity, and building interpersonal relationships. Taken together, these three chapters illuminate the process of designing a rich OST learning environment and the kinds of learning in practice that occurred for adult learners learning to be mentors through their participation in the COOL OST program. In

  10. Should deciduous teeth be preserved in adult patients? How about stem cells? Is it reasonable to preserve them?

    PubMed Central

    Consolaro, Alberto

    2016-01-01

    Abstract When seeking orthodontic treatment, many adolescents and adult patients present with deciduous teeth. Naturally, deciduous teeth will inevitably undergo exfoliation at the expected time or at a later time. Apoptosis is the biological trigger of root resorption. In adult patients, deciduous teeth should not be preserved, as they promote: infraocclusion, traumatic occlusion, occlusal trauma, diastemata and size as well as morphology discrepancy malocclusion. Orthodontic movement speeds root resorption up, and so do restoring or recontouring deciduous teeth in order to establish esthetics and function. Deciduous teeth cells are dying as a result of apoptosis, and their regeneration potential, which allows them to act as stem cells, is limited. On the contrary, adult teeth cells have a greater proliferative potential. All kinds of stem cell therapies are laboratory investigative non authorized trials. PMID:27275612

  11. Should deciduous teeth be preserved in adult patients? How about stem cells? Is it reasonable to preserve them?

    PubMed

    Consolaro, Alberto

    2016-01-01

    When seeking orthodontic treatment, many adolescents and adult patients present with deciduous teeth. Naturally, deciduous teeth will inevitably undergo exfoliation at the expected time or at a later time. Apoptosis is the biological trigger of root resorption. In adult patients, deciduous teeth should not be preserved, as they promote: infraocclusion, traumatic occlusion, occlusal trauma, diastemata and size as well as morphology discrepancy malocclusion. Orthodontic movement speeds root resorption up, and so do restoring or recontouring deciduous teeth in order to establish esthetics and function. Deciduous teeth cells are dying as a result of apoptosis, and their regeneration potential, which allows them to act as stem cells, is limited. On the contrary, adult teeth cells have a greater proliferative potential. All kinds of stem cell therapies are laboratory investigative non authorized trials.

  12. CD44 Transmembrane Receptor and Hyaluronan Regulate Adult Hippocampal Neural Stem Cell Quiescence and Differentiation.

    PubMed

    Su, Weiping; Foster, Scott C; Xing, Rubing; Feistel, Kerstin; Olsen, Reid H J; Acevedo, Summer F; Raber, Jacob; Sherman, Larry S

    2017-03-17

    Adult neurogenesis in the hippocampal subgranular zone (SGZ) is involved in learning and memory throughout life but declines with aging. Mice lacking the CD44 transmembrane receptor for the glycosaminoglycan hyaluronan (HA) demonstrate a number of neurological disturbances including hippocampal memory deficits, implicating CD44 in the processes underlying hippocampal memory encoding, storage, or retrieval. Here, we found that HA and CD44 play important roles in regulating adult neurogenesis, and we provide evidence that HA contributes to age-related reductions in neural stem cell (NSC) expansion and differentiation in the hippocampus. CD44-expressing NSCs isolated from the mouse SGZ are self-renewing and capable of differentiating into neurons, astrocytes, and oligodendrocytes. Mice lacking CD44 demonstrate increases in NSC proliferation in the SGZ. This increased proliferation is also observed in NSCs grown in vitro, suggesting that CD44 functions to regulate NSC proliferation in a cell-autonomous manner. HA is synthesized by NSCs and increases in the SGZ with aging. Treating wild type but not CD44-null NSCs with HA inhibits NSC proliferation. HA digestion in wild type NSC cultures or in the SGZ induces increased NSC proliferation, and CD44-null as well as HA-disrupted wild type NSCs demonstrate delayed neuronal differentiation. HA therefore signals through CD44 to regulate NSC quiescence and differentiation, and HA accumulation in the SGZ may contribute to reductions in neurogenesis that are linked to age-related decline in spatial memory.

  13. Mitochondria defects are involved in lead-acetate-induced adult hematopoietic stem cell decline.

    PubMed

    Liu, Jun; Jia, Dao-Yong; Cai, Shi-Zhong; Li, Cheng-Peng; Zhang, Meng-Si; Zhang, Yan-Yan; Yan, Chong-Huai; Wang, Ya-Ping

    2015-05-19

    Occupational high-grade lead exposure has been reduced in recent decades as a result of increased regulation. However, environmental lead exposure remains widespread, and is associated with severe toxicity implicated in human diseases. We performed oral intragastric administration of various dose lead acetate to adult Sprague Dawley rats to define the role of lead exposure in hematopoietic stem cells (HSCs) function, and to clarify its underlying mechanism. Lead acetate-exposed rats exhibited developmental abnormalities in myeloid and lymphoid lineages, and a significant decline in immune functions. It also showed HSCs functional decline associated with senescent phenotype with low grade lead acetate exposure or apoptotic phenotype with relative higher grade dose exposure. Mechanistic exploration showed a significant increase in reactive oxygen species (ROS) in the lead acetate-exposed CD90(+)CD45(-) compartment, which correlated with functional defects in cellular mitochondria. Furthermore, in vivo treatment with the antioxidant vitamin C led to reversion of the CD90(+)CD45(-) compartment functional decline. These results indicate that lead acetate perturbs the hematopoietic balance of adult HSCs, associated with cellular mitochondria defects, increased intracellular ROS generation.

  14. Serotonin Depletion Hampers Survival and Proliferation in Neurospheres Derived from Adult Neural Stem Cells

    PubMed Central

    Benninghoff, Jens; Gritti, Angela; Rizzi, Matteo; LaMorte, Giuseppe; Schloesser, Robert J; Schmitt, Angelika; Robel, Stefanie; Genius, Just; Moessner, Rainald; Riederer, Peter; Manji, Husseini K; Grunze, Heinz; Rujescu, Dan; Moeller, Hans-Juergen; Lesch, Klaus-Peter; Vescovi, Angelo Luigi

    2010-01-01

    Serotonin (5-HT) and the serotonergic system have recently been indicated as modulators of adult hippocampal neurogenesis. In this study, we evaluated the role of 5-HT on the functional features in neurospheres derived from adult neural stem cells (ANSC). We cultured neurospheres derived from mouse hippocampus in serum-free medium containing epidermal (EGF) and type-2 fibroblast growth factor (FGF2). Under these conditions ANSC expressed both isoforms of tryptophane-hydroxylase (TPH) and produced 5-HT. Blocking TPH function by para-chlorophenylalanine (PCPA) reduced ANSC proliferation, which was rescued by exogenous 5-HT. 5-HT action on ANSC was mediated predominantly by the serotonin receptor subtype 5-HT1A and, to a lesser extent, through the 5-HT2C (receptor) subtype, as shown by selectively antagonizing these receptors. Finally, we documented a 5-HT-induced increase of ANSC migration activity. In summary, we demonstrated a powerful serotonergic impact on ANSC functional features, which was mainly mediated by 5-HT1A receptors. PMID:20010549

  15. Serotonin depletion hampers survival and proliferation in neurospheres derived from adult neural stem cells.

    PubMed

    Benninghoff, Jens; Gritti, Angela; Rizzi, Matteo; Lamorte, Giuseppe; Schloesser, Robert J; Schmitt, Angelika; Robel, Stefanie; Genius, Just; Moessner, Rainald; Riederer, Peter; Manji, Husseini K; Grunze, Heinz; Rujescu, Dan; Moeller, Hans-Juergen; Lesch, Klaus-Peter; Vescovi, Angelo Luigi

    2010-03-01

    Serotonin (5-HT) and the serotonergic system have recently been indicated as modulators of adult hippocampal neurogenesis. In this study, we evaluated the role of 5-HT on the functional features in neurospheres derived from adult neural stem cells (ANSC). We cultured neurospheres derived from mouse hippocampus in serum-free medium containing epidermal (EGF) and type-2 fibroblast growth factor (FGF2). Under these conditions ANSC expressed both isoforms of tryptophane-hydroxylase (TPH) and produced 5-HT. Blocking TPH function by para-chlorophenylalanine (PCPA) reduced ANSC proliferation, which was rescued by exogenous 5-HT. 5-HT action on ANSC was mediated predominantly by the serotonin receptor subtype 5-HT1A and, to a lesser extent, through the 5-HT2C (receptor) subtype, as shown by selectively antagonizing these receptors. Finally, we documented a 5-HT-induced increase of ANSC migration activity. In summary, we demonstrated a powerful serotonergic impact on ANSC functional features, which was mainly mediated by 5-HT1A receptors.

  16. T-cell suicide gene therapy prompts thymic renewal in adults after hematopoietic stem cell transplantation.

    PubMed

    Vago, Luca; Oliveira, Giacomo; Bondanza, Attilio; Noviello, Maddalena; Soldati, Corrado; Ghio, Domenico; Brigida, Immacolata; Greco, Raffaella; Lupo Stanghellini, Maria Teresa; Peccatori, Jacopo; Fracchia, Sergio; Del Fiacco, Matteo; Traversari, Catia; Aiuti, Alessandro; Del Maschio, Alessandro; Bordignon, Claudio; Ciceri, Fabio; Bonini, Chiara

    2012-08-30

    The genetic modification of T cells with a suicide gene grants a mechanism of control of adverse reactions, allowing safe infusion after partially incompatible hematopoietic stem cell transplantation (HSCT). In the TK007 clinical trial, 22 adults with hematologic malignancies experienced a rapid and sustained immune recovery after T cell-depleted HSCT and serial infusions of purified donor T cells expressing the HSV thymidine kinase suicide gene (TK+ cells). After a first wave of circulating TK+ cells, the majority of T cells supporting long-term immune reconstitution did not carry the suicide gene and displayed high numbers of naive lymphocytes, suggesting the thymus-dependent development of T cells, occurring only upon TK+ -cell engraftment. Accordingly, after the infusions, we documented an increase in circulating TCR excision circles and CD31+ recent thymic emigrants and a substantial expansion of the active thymic tissue as shown by chest tomography scans. Interestingly, a peak in the serum level of IL-7 was observed after each infusion of TK+ cells, anticipating the appearance of newly generated T cells. The results of the present study show that the infusion of genetically modified donor T cells after HSCT can drive the recovery of thymic activity in adults, leading to immune reconstitution.

  17. Adult vascular smooth muscle cells in culture express neural stem cell markers typical of resident multipotent vascular stem cells.

    PubMed

    Kennedy, Eimear; Mooney, Ciaran J; Hakimjavadi, Roya; Fitzpatrick, Emma; Guha, Shaunta; Collins, Laura E; Loscher, Christine E; Morrow, David; Redmond, Eileen M; Cahill, Paul A

    2014-10-01

    Differentiation of resident multipotent vascular stem cells (MVSCs) or de-differentiation of vascular smooth muscle cells (vSMCs) might be responsible for the SMC phenotype that plays a major role in vascular diseases such as arteriosclerosis and restenosis. We examined vSMCs from three different species (rat, murine and bovine) to establish whether they exhibit neural stem cell characteristics typical of MVSCs. We determined their SMC differentiation, neural stem cell marker expression and multipotency following induction in vitro by using immunocytochemistry, confocal microscopy, fluorescence-activated cell sorting analysis and quantitative real-time polymerase chain reaction. MVSCs isolated from rat aortic explants, enzymatically dispersed rat SMCs and rat bone-marrow-derived mesenchymal stem cells served as controls. Murine carotid artery lysates and primary rat aortic vSMCs were both myosin-heavy-chain-positive but weakly expressed the neural crest stem cell marker, Sox10. Each vSMC line examined expressed SMC differentiation markers (smooth muscle α-actin, myosin heavy chain and calponin), neural crest stem cell markers (Sox10(+), Sox17(+)) and a glia marker (S100β(+)). Serum deprivation significantly increased calponin and myosin heavy chain expression and decreased stem cell marker expression, when compared with serum-rich conditions. vSMCs did not differentiate to adipocytes or osteoblasts following adipogenic or osteogenic inductive stimulation, respectively, or respond to transforming growth factor-β1 or Notch following γ-secretase inhibition. Thus, vascular SMCs in culture express neural stem cell markers typical of MVSCs, concomitant with SMC differentiation markers, but do not retain their multipotency. The ultimate origin of these cells might have important implications for their use in investigations of vascular proliferative disease in vitro.

  18. Why Adult Stem Cell Functionality Declines with Age? Studies from the Fruit Fly Drosophila Melanogaster Model Organism

    PubMed Central

    Gonen, Oren; Toledano, Hila

    2014-01-01

    Highly regenerative adult tissues are supported by rare populations of stem cells that continuously divide to self-renew and generate differentiated progeny. This process is tightly regulated by signals emanating from surrounding cells to fulfill the dynamic demands of the tissue. One of the hallmarks of aging is slow and aberrant tissue regeneration due to deteriorated function of stem and supporting cells. Several Drosophila regenerative tissues are unique in that they provide exact identification of stem and neighboring cells in whole-tissue anatomy. This allows for precise tracking of age-related changes as well as their targeted manipulation within the tissue. In this review we present the stem cell niche of Drosophila testis, ovary and intestine and describe the major changes and phenotypes that occur in the course of aging. Specifically we discuss changes in both intrinsic properties of stem cells and their microenvironment that contribute to the decline in tissue functionality. Understanding these mechanisms in adult Drosophila tissues will likely provide new paradigms in the field of aging. PMID:24955030

  19. Reserve stem cells: Differentiated cells reprogram to fuel repair, metaplasia, and neoplasia in the adult gastrointestinal tract.

    PubMed

    Mills, Jason C; Sansom, Owen J

    2015-07-14

    It has long been known that differentiated cells can switch fates, especially in vitro, but only recently has there been a critical mass of publications describing the mechanisms adult, postmitotic cells use in vivo to reverse their differentiation state. We propose that this sort of cellular reprogramming is a fundamental cellular process akin to apoptosis or mitosis. Because reprogramming can invoke regenerative cells from mature cells, it is critical to the long-term maintenance of tissues like the pancreas, which encounter large insults during adulthood but lack constitutively active adult stem cells to repair the damage. However, even in tissues with adult stem cells, like the stomach and intestine, reprogramming may allow mature cells to serve as reserve ("quiescent") stem cells when normal stem cells are compromised. We propose that the potential downside to reprogramming is that it increases risk for cancers that occur late in adulthood. Mature, long-lived cells may have years of exposure to mutagens. Mutations that affect the physiological function of differentiated, postmitotic cells may lead to apoptosis, but mutations in genes that govern proliferation might not be selected against. Hence, reprogramming with reentry into the cell cycle might unmask those mutations, causing an irreversible progenitor-like, proliferative state. We review recent evidence showing that reprogramming fuels irreversible metaplastic and precancerous proliferation in the stomach and pancreas. Finally, we illustrate how we think reprogrammed differentiated cells are likely candidates as cells of origin for cancers of the intestine.

  20. KCTD11 expression in medulloblastoma is lower than in adult cerebellum and higher than in neural stem cells.

    PubMed

    Zawlik, Izabela; Zakrzewska, Magdalena; Witusik, Monika; Golanska, Ewa; Kulczycka-Wojdala, Dominika; Szybka, Malgorzata; Piaskowski, Sylwester; Wozniak, Krystyna; Zakrzewski, Krzysztof; Papierz, Wielislaw; Liberski, Pawel P; Rieske, Piotr

    2006-10-01

    Medulloblastoma (MB) is the most common malignant brain tumor of childhood, and the most frequent associated genetic alteration is loss of heterozygosity on chromosome region 7p13. Two genes mapping to this region, KCTD11 (alias REN) and HIC1, have been proposed as involved in MB pathogenesis. We used real-time polymerase chain reaction in 20 tissue samples of primary MB to examine the transcriptional level of the two genes, with reference to two types of controls: adult cerebellum and fetal neural stem cells. A significant reduction of KCTD11 expression relative to adult normal cerebellum was detected in 14 of 20 (70%) of MB samples. Neural stem cells had even lower levels of KCTD11 expression than did MB. HIC1 gene expression was low ( approximately 100 times lower than KCTD11 expression) in MB, and low also in both adult cerebellum and neural stem cells. Hypermethylation of the 5'UTR or the central region of HIC1 (or both) was detected in a significant number of MB samples, as well as in cerebellum and neural stem cells. Our data suggest that KCTD11 may play an important role in MB tumorigenesis, but do not support the role of HIC1 in this tumor development. We argue that recognition of the gene or genes important in MB tumorigenesis depends in part on defining an appropriate control.

  1. Reserve stem cells: Reprogramming of differentiated cells fuels repair, metaplasia, and neoplasia in the adult gastrointestinal tract

    PubMed Central

    Mills, Jason C.; Sansom, Owen J.

    2016-01-01

    It has long been known that differentiated cells can switch fates, especially in vitro, but only recently has there been a critical mass of publications describing the mechanisms adult, post-mitotic cells use in vivo to reverse their differentiation state. We propose that this sort of cellular reprogramming is a fundamental cellular process akin to apoptosis or mitosis. Because reprogramming can invoke regenerative cells from mature cells, it is critical to the longterm maintenance of tissues like the pancreas, which encounter large insults during adulthood but lack constitutively active adult stem cells to repair the damage. However, even in tissues with adult stem cells, like stomach and intestine, reprogramming may allow mature cells to serve as reserve (“quiescent”) stem cells when normal stem cells are compromised. We propose that the potential downside to reprogramming is that it increases risk for cancers that occur late in adulthood. Mature, long-lived cells may have years of exposure to mutagens. Mutations that affect the physiological function of differentiated, post-mitotic cells may lead to apoptosis, but mutations in genes that govern proliferation might not be selected against. Hence, reprogramming with reentry into the cell cycle might unmask those mutations, causing an irreversible progenitor-like, proliferative state. We review recent evidence showing that reprogramming fuels irreversible metaplastic and precancerous proliferations in stomach and pancreas. Finally, we illustrate how we think reprogrammed differentiated cells are likely candidates as cells of origin for cancers of the intestine. PMID:26175494

  2. The adult pituitary shows stem/progenitor cell activation in response to injury and is capable of regeneration.

    PubMed

    Fu, Qiuli; Gremeaux, Lies; Luque, Raul M; Liekens, Daisy; Chen, Jianghai; Buch, Thorsten; Waisman, Ari; Kineman, Rhonda; Vankelecom, Hugo

    2012-07-01

    The pituitary gland constitutes, together with the hypothalamus, the regulatory core of the endocrine system. Whether the gland is capable of cell regeneration after injury, in particular when suffered at adult age, is unknown. To investigate the adult pituitary's regenerative capacity and the response of its stem/progenitor cell compartment to damage, we constructed a transgenic mouse model to conditionally destroy pituitary cells. GHCre/iDTR mice express diphtheria toxin (DT) receptor after transcriptional activation by Cre recombinase, which is driven by the GH promoter. Treatment with DT for 3 d leads to gradual GH(+) (somatotrope) cell obliteration with a final ablation grade of 80-90% 1 wk later. The stem/progenitor cell-clustering side population promptly expands after injury, concordant with the immediate increase in Sox2(+) stem/progenitor cells. In addition, folliculo-stellate cells, previously designated as pituitary stem/progenitor cells and significantly overlapping with Sox2(+) cells, also increase in abundance. In situ examination reveals expansion of the Sox2(+) marginal-zone niche and appearance of remarkable Sox2(+) cells that contain GH. When mice are left after the DT-provoked lesion, GH(+) cells considerably regenerate during the following months. Double Sox2(+)/GH(+) cells are observed throughout the regenerative period, suggesting recovery of somatotropes from stem/progenitor cells, as further supported by 5-ethynyl-2'-deoxyuridine (EdU) pulse-chase lineage tracing. In conclusion, our study demonstrates that the adult pituitary gland holds regenerative competence and that tissue repair follows prompt activation and plausible involvement of the stem/progenitor cells.

  3. Irradiation of juvenile, but not adult, mammary gland increases stem cell self-renewal and estrogen receptor negative tumors.

    PubMed

    Tang, Jonathan; Fernandez-Garcia, Ignacio; Vijayakumar, Sangeetha; Martinez-Ruis, Haydeliz; Illa-Bochaca, Irineu; Nguyen, David H; Mao, Jian-Hua; Costes, Sylvain V; Barcellos-Hoff, Mary Helen

    2014-03-01

    Children exposed to ionizing radiation have a substantially greater breast cancer risk than adults; the mechanism for this strong age dependence is not known. Here we show that pubertal murine mammary glands exposed to sparsely or densely ionizing radiation exhibit enrichment of mammary stem cell and Notch pathways, increased mammary repopulating activity indicative of more stem cells, and propensity to develop estrogen receptor (ER) negative tumors thought to arise from stem cells. We developed a mammary lineage agent-based model (ABM) to evaluate cell inactivation, self-renewal, or dedifferentiation via epithelial-mesenchymal transition (EMT) as mechanisms by which radiation could increase stem cells. ABM rejected cell inactivation and predicted increased self-renewal would only affect juveniles while dedifferentiation could act in both juveniles and adults. To further test self-renewal versus dedifferentiation, we used the MCF10A human mammary epithelial cell line, which recapitulates ductal morphogenesis in humanized fat pads, undergoes EMT in response to radiation and transforming growth factor β (TGFβ) and contains rare stem-like cells that are Let-7c negative or express both basal and luminal cytokeratins. ABM simulation of population dynamics of double cytokeratin cells supported increased self-renewal in irradiated MCF10A treated with TGFβ. Radiation-induced Notch concomitant with TGFβ was necessary for increased self-renewal of Let-7c negative MCF10A cells but not for EMT, indicating that these are independent processes. Consistent with these data, irradiating adult mice did not increase mammary repopulating activity or ER-negative tumors. These studies suggest that irradiation during puberty transiently increases stem cell self-renewal, which increases susceptibility to developing ER-negative breast cancer.

  4. Thyroid Hormone-Induced Activation of Notch Signaling is Required for Adult Intestinal Stem Cell Development During Xenopus Laevis Metamorphosis.

    PubMed

    Hasebe, Takashi; Fujimoto, Kenta; Kajita, Mitsuko; Fu, Liezhen; Shi, Yun-Bo; Ishizuya-Oka, Atsuko

    2016-11-21

    In Xenopus laevis intestine during metamorphosis, the larval epithelial cells are removed by apoptosis, and the adult epithelial stem (AE) cells appear concomitantly. They proliferate and differentiate to form the adult epithelium (Ep). Thyroid hormone (TH) is well established to trigger this remodeling by regulating the expression of various genes including Notch receptor. To study the role of Notch signaling, we have analyzed the expression of its components, including the ligands (DLL and Jag), receptor (Notch), and targets (Hairy), in the metamorphosing intestine by real-time reverse transcription-polymerase chain reaction and in situ hybridization or immunohistochemistry. We show that they are up-regulated during both natural and TH-induced metamorphosis in a tissue-specific manner. Particularly, Hairy1 is specifically expressed in the AE cells. Moreover, up-regulation of Hairy1 and Hairy2b by TH was prevented by treating tadpoles with a γ-secretase inhibitor (GSI), which inhibits Notch signaling. More importantly, TH-induced up-regulation of LGR5, an adult intestinal stem cell marker, was suppressed by GSI treatment. Our results suggest that Notch signaling plays a role in stem cell development by regulating the expression of Hairy genes during intestinal remodeling. Furthermore, we show with organ culture experiments that prolonged exposure of tadpole intestine to TH plus GSI leads to hyperplasia of secretory cells and reduction of absorptive cells. Our findings here thus provide evidence for evolutionarily conserved role of Notch signaling in intestinal cell fate determination but more importantly reveal, for the first time, an important role of Notch pathway in the formation of adult intestinal stem cells during vertebrate development. Stem Cells 2016.

  5. Oct-4 expression in adult human differentiated cells challenges its role as a pure stem cell marker.

    PubMed

    Zangrossi, Stefano; Marabese, Mirko; Broggini, Massimo; Giordano, Rosaria; D'Erasmo, Marco; Montelatici, Elisa; Intini, Daniela; Neri, Antonino; Pesce, Maurizio; Rebulla, Paolo; Lazzari, Lorenza

    2007-07-01

    The Oct-4 transcription factor, a member of the POU family that is also known as Oct-3 and Oct3/4, is expressed in totipotent embryonic stem cells (ES) and germ cells, and it has a unique role in development and in the determination of pluripotency. ES may have their postnatal counterpart in the adult stem cells, recently described in various mammalian tissues, and Oct-4 expression in putative stem cells purified from adult tissues has been considered a real marker of stemness. In this context, normal mature adult cells would not be expected to show Oct-4 expression. On the contrary, we demonstrated, using reverse transcription-polymerase chain reaction (PCR) (total RNA, Poly A+), real-time PCR, immunoprecipitation, Western blotting, band shift, and immunofluorescence, that human peripheral blood mononuclear cells, genetically stable and mainly terminally differentiated cells with well defined functions and a limited lifespan, express Oct-4. These observations raise the question as to whether the role of Oct-4 as a marker of pluripotency should be challenged. Our findings suggest that the presence of Oct-4 is not sufficient to define a cell as pluripotent, and that additional measures should be used to avoid misleading results in the case of an embryonic-specific gene with a large number of pseudogenes that may contribute to false identification of Oct-4 in adult stem cells. These unexpected findings may provide new insights into the role of Oct-4 in fully differentiated cells. Disclosure of potential conflicts of interest is found at the end of this article.

  6. How to mend a broken heart: adult and induced pluripotent stem cell therapy for heart repair and regeneration.

    PubMed

    Wegener, Marie; Bader, Augustinus; Giri, Shibashish

    2015-06-01

    The recently developed ability to differentiate primary adult stem cells and induced pluripotent stem cells (iPSCs) into cardiomyocytes is providing unprecedented opportunities to produce an unlimited supply of cardiomyocytes for use in patients with heart disease. Here, we examine the evidence for the preclinical use of such cells for successful heart regeneration. We also describe advances in the identification of new cardiac molecular and cellular targets to induce proliferation of cardiomyocytes for heart regeneration. Such new advances are paving the way for a new innovative drug development process for the treatment of heart disease.

  7. Apoptosis of melanocytes in vitiligo results from antibody penetration.

    PubMed

    Ruiz-Argüelles, Alejandro; Brito, Gustavo Jiménez; Reyes-Izquierdo, Paola; Pérez-Romano, Beatriz; Sánchez-Sosa, Sergio

    2007-12-01

    Vitiligo is a rather common disease characterized by depigmentation of skin and mucosae due to the loss of melanocytes, most likely as a result of autoimmune phenomena. In this study we demonstrated apoptotic markers in residual melanocytes in skin biopsies of patients with vitiligo, as well as the presence of serum antibodies to melanocyte-specific antigens in the vast majority of patients. Moreover, we were able to prove that serum IgG antibodies from vitiligo patients, but not from healthy controls, were capable to penetrate into cultured melanocytes in vitro, and trigger them to engage in apoptosis. Our results are consonant with the theory that melanocyte-specific antibodies are responsible for the deletion of melanocytes through antibody penetration and apoptosis.

  8. Expression of ezrin in subventricular zone neural stem cells and their progeny in adult and developing mice.

    PubMed

    Moon, Younghye; Kim, Joo Yeon; Choi, So Yoen; Cho, Hyo Min; Kim, Hyun; Sun, Woong

    2013-03-01

    Ezrin is a member of the ezrin-radixin-moesin (ERM) family of proteins, which link the cytoskeleton and cell membrane. ERM proteins are involved in pivotal cellular functions including cell-matrix recognition, cell-cell communication, and cell motility. Several recent studies have shown that ERM proteins are expressed in specific cell types of the adult rostral migratory stream (RMS). In this study, we found that ERM proteins are expressed highly in the early postnatal RMS and the ventricular zone of embryonic cerebral cortex, suggesting that these proteins may be expressed by neural progenitors. Furthermore, whereas ezrin previously was found to be expressed exclusively by astrocytes of the adult RMS, we found that ezrin-expressing cells also expressed the markers for indicating neuroblasts in vivo and in vitro, and that ezrin expression by neuroblasts decreases progressively as neuroblasts migrate. Using in vitro differentiation of adult neural stem cells, we found that ezrin is expressed by neural stem cells and their progeny (neuroblasts and astrocytes), but not by oligodendrocytic progeny. Collectively our findings demonstrate that adult neural stem cells and neuroblasts express ezrin and that ezrin may be involved in intracellular actin remodeling.

  9. Evidence of progenitor cells of glandular and myoepithelial cell lineages in the human adult female breast epithelium: a new progenitor (adult stem) cell concept.

    PubMed

    Boecker, Werner; Buerger, Horst

    2003-10-01

    Although experimental data clearly confirm the existence of self-renewing mammary stem cells, the characteristics of such progenitor cells have never been satisfactorily defined. Using a double immunofluorescence technique for simultaneous detection of the basal cytokeratin 5, the glandular cytokeratins 8/18 and the myoepithelial differentiation marker smooth muscle actin (SMA), we were able to demonstrate the presence of CK5+ cells in human adult breast epithelium. These cells have the potential to differentiate to either glandular (CK8/18+) or myoepithelial cells (SMA+) through intermediary cells (CK5+ and CK8/18+ or SMA+). We therefore proceeded on the assumption that the CK5+ cells are phenotypically and behaviourally progenitor (committed adult stem) cells of human breast epithelium. Furthermore, we furnish evidence that most of these progenitor cells are located in the luminal epithelium of the ductal lobular tree. Based on data obtained in extensive analyses of proliferative breast disease lesions, we have come to regard usual ductal hyperplasia as a progenitor cell-derived lesion, whereas most breast cancers seem to evolve from differentiated glandular cells. Double immunofluorescence experiments provide a new tool to characterize phenotypically progenitor (adult stem) cells and their progenies. This model has been shown to be of great value for a better understanding not only of normal tissue regeneration but also of proliferative breast disease. Furthermore, this model provides a new tool for unravelling further the regulatory mechanisms that govern normal and pathological cell growth.

  10. Designer Self-Assembling Peptide Nanofiber Scaffolds for Adult Mouse Neural Stem Cell 3-Dimensional Cultures

    PubMed Central

    Gelain, Fabrizio; Bottai, Daniele; Vescovi, Angleo; Zhang, Shuguang

    2006-01-01

    Biomedical researchers have become increasingly aware of the limitations of conventional 2-dimensional tissue cell culture systems, including coated Petri dishes, multi-well plates and slides, to fully address many critical issues in cell biology, cancer biology and neurobiology, such as the 3-D microenvironment, 3-D gradient diffusion, 3-D cell migration and 3-D cell-cell contact interactions. In order to fully understand how cells behave in the 3-D body, it is important to develop a well-controlled 3-D cell culture system where every single ingredient is known. Here we report the development of a 3-D cell culture system using a designer peptide nanofiber scaffold with mouse adult neural stem cells. We attached several functional motifs, including cell adhesion, differentiation and bone marrow homing motifs, to a self-assembling peptide RADA16 (Ac-RADARADARADARADA-COHN2). These functionalized peptides undergo self-assembly into a nanofiber structure similar to Matrigel. During cell culture, the cells were fully embedded in the 3-D environment of the scaffold. Two of the peptide scaffolds containing bone marrow homing motifs significantly enhanced the neural cell survival without extra soluble growth and neurotrophic factors to the routine cell culture media. In these designer scaffolds, the cell populations with β-Tubulin+, GFAP+ and Nestin+ markers are similar to those found in cell populations cultured on Matrigel. The gene expression profiling array experiments showed selective gene expression, possibly involved in neural stem cell adhesion and differentiation. Because the synthetic peptides are intrinsically pure and a number of desired function cellular motifs are easy to incorporate, these designer peptide nanofiber scaffolds provide a promising controlled 3-D culture system for diverse tissue cells, and are useful as well for general molecular and cell biology. PMID:17205123

  11. Ex-Vivo Tissues Engineering Modeling for Reconstructive Surgery Using Human Adult Adipose Stem Cells and Polymeric Nanostructured Matrix

    PubMed Central

    Morena, Francesco; Argentati, Chiara; Calzoni, Eleonora; Cordellini, Marino; Emiliani, Carla; D’Angelo, Francesco; Martino, Sabata

    2016-01-01

    The major challenge for stem cell translation regenerative medicine is the regeneration of damaged tissues by creating biological substitutes capable of recapitulating the missing function in the recipient host. Therefore, the current paradigm of tissue engineering strategies is the combination of a selected stem cell type, based on their capability to differentiate toward committed cell lineages, and a biomaterial, that, due to own characteristics (e.g., chemical, electric, mechanical property, nano-topography, and nanostructured molecular components), could serve as active scaffold to generate a bio-hybrid tissue/organ. Thus, effort has been made on the generation of in vitro tissue engineering modeling. Here, we present an in vitro model where human adipose stem cells isolated from lipoaspirate adipose tissue and breast adipose tissue, cultured on polymeric INTEGRA® Meshed Bilayer Wound Matrix (selected based on conventional clinical applications) are evaluated for their potential application for reconstructive surgery toward bone and adipose tissue. We demonstrated that human adipose stem cells isolated from lipoaspirate and breast tissue have similar stemness properties and are suitable for tissue engineering applications. Finally, the overall results highlighted lipoaspirate adipose tissue as a good source for the generation of adult adipose stem cells.

  12. Limited Ca2+ and PKA-pathway dependent neurogenic differentiation of human adult mesenchymal stem cells as compared to fetal neuronal stem cells.

    PubMed

    Lepski, Guilherme; Jannes, Cinthia Elim; Maciaczyk, Jaroslaw; Papazoglou, Anna; Mehlhorn, Alexander T; Kaiser, Stefan; Teixeira, Manoel Jacobsen; Marie, Suely K N; Bischofberger, Josef; Nikkhah, Guido

    2010-01-15

    The ability of mesenchymal stem cells to generate functional neurons in culture is still a matter of controversy. In order to assess this issue, we performed a functional comparison between neuronal differentiation of human MSCs and fetal-derived neural stem cells (NSCs) based on morphological, immunocytochemical, and electrophysiological criteria. Furthermore, possible biochemical mechanisms involved in this process were presented. NF200 immunostaining was used to quantify the yield of differentiated cells after exposure to cAMP. The addition of a PKA inhibitor and Ca(2+) blockers to the differentiation medium significantly reduced the yield of differentiated cells. Activation of CREB was also observed on MSCs during maturation. Na(+)-, K(+)-, and Ca(2+)-voltage-dependent currents were recorded from MSCs-derived cells. In contrast, significantly larger Na(+) currents, firing activity, and spontaneous synaptic currents were recorded from NSCs. Our results indicate that the initial neuronal differentiation of MSCs is induced by cAMP and seems to be dependent upon Ca(2+) and the PKA pathway. However, compared to fetal neural stem cells, adult mesenchymal counterparts are limited in their neurogenic potential. Despite the similar yield of neuronal cells, NSCs achieved a more mature functional state. Description of the underlying mechanisms that govern MSCs' differentiation toward a stable neuronal phenotype and their limitations provides a unique opportunity to enhance our understanding of stem cell plasticity.

  13. Adult Bone Marrow Neural Crest Stem Cells and Mesenchymal Stem Cells Are Not Able to Replace Lost Neurons in Acute MPTP-Lesioned Mice

    PubMed Central

    Neirinckx, Virginie; Marquet, Alice; Coste, Cécile

    2013-01-01

    Adult bone marrow stroma contains multipotent stem cells (BMSC) that are a mixed population of mesenchymal and neural-crest derived stem cells. Both cells are endowed with in vitro multi-lineage differentiation abilities, then constituting an attractive and easy-available source of material for cell therapy in neurological disorders. Whereas the in vivo integration and differentiation of BMSC in neurons into the central nervous system is currently matter of debate, we report here that once injected into the striatum of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-treated mice, pure populations of either bone marrow neural crest stem cells (NCSC) or mesenchymal stem cells (MSC) survived only transiently into the lesioned brain. Moreover, they do not migrate through the brain tissue, neither modify their initial phenotype, while no recovery of the dopaminergic system integrity was observed. Consequently, we tend to conclude that MSC/NCSC are not able to replace lost neurons in acute MPTP-lesioned dopaminergic system through a suitable integration and/or differentiation process. Altogether with recent data, it appears that neuroprotective, neurotrophic and anti-inflammatory features characterizing BMSC are of greater interest as regards CNS lesions management. PMID:23741377

  14. The inflammatory infiltrate of melanocytic nevus.

    PubMed

    Fernandez-Flores, Angel; Saeb-Lima, Marcela

    2014-01-01

    Melanocytic nevi are frequently accompanied by inflammatory cells of different types, in varied amounts and distributed in different patterns. In the current report, we review the knowledge on inflammation seen in different types of melanocytic nevi. As an additional contribution, we studied the lymphocytic inflammatory component of Duperrat nevus, as well as the cytotoxic component of Sutton nevus, two contributions that we have not found in the literature. We conclude that: (a) Duperrat nevus has a mixed inflammatory reaction that includes histiocytes, foreign-body multinucleated giant cells, polymorphonuclears, lymphocytes (predominantly CD4+) and plasma cells (commonly abundant); (b) common melanocytic nevi with reactive inflammatory infiltrate usually show a CD4+ predominant population; (c) Meyerson nevus commonly shows an inflammatory infiltrate mainly made up of CD4+ T-cells; (d) Sutton nevus with halo phenomenon is accompanied by a dense inflammatory infiltrate with lymphocytes in a CD4:CD8 ratio varying from 1:1 to 1:3 and in which most of the CD8+ T-cells do not express cytotoxic markers; (e) Wiesner nevus commonly shows a spare lymphocytic infiltrate but the nature of the infiltrate has not yet been investigated.

  15. Culture bag systems for clinical applications of adult human neural crest-derived stem cells

    PubMed Central

    2014-01-01

    Introduction Facing the challenging treatment of neurodegenerative diseases as well as complex craniofacial injuries such as those common after cancer therapy, the field of regenerative medicine increasingly relies on stem cell transplantation strategies. Here, neural crest-derived stem cells (NCSCs) offer many promising applications, although scale up of clinical-grade processes prior to potential transplantations is currently limiting. In this study, we aimed to establish a clinical-grade, cost-reducing cultivation system for NCSCs isolated from the adult human nose using cGMP-grade Afc-FEP bags. Methods We cultivated human neural crest-derived stem cells from inferior turbinate (ITSCs) in a cell culture bag system using Afc-FEP bags in human blood plasma-supplemented medium. Investigations of viability, proliferation and expression profile of bag-cultured ITSCs were followed by DNA-content and telomerase activity determination. Cultivated ITSCs were introduced to directed in vitro differentiation assays to assess their potential for mesodermal and ectodermal differentiation. Mesodermal differentiation was determined using an enzyme activity assay (alkaline phosphatase, ALP), respective stainings (Alizarin Red S, Von Kossa and Oil Red O), and RT-PCR, while immunocytochemistry and synaptic vesicle recycling were applied to assay neuroectodermal differentiation of ITSCs. Results When cultivated within Afc-FEP bags, ITSCs grew three-dimensionally in a human blood plasma-derived matrix, thereby showing unchanged morphology, proliferation capability, viability and expression profile in comparison to three dimensionally-cultured ITSCs growing in standard cell culture plastics. Genetic stability of bag-cultured ITSCs was further accompanied by unchanged telomerase activity. Importantly, ITSCs retained their potential to differentiate into mesodermal cell types, particularly including ALP-active, Alizarin Red S-, and Von Kossa-positive osteogenic cell types, as well as

  16. Hematopoietic stem cell transplantation from alternative sources in adults with high-risk acute leukemia.

    PubMed

    Aversa, Franco; Reisner, Yair; Martelli, Massimo F

    2004-01-01

    Since 75% of patients with high-risk acute leukemia do not have a human leukocyte antigen (HLA)-identical sibling, alternative sources for hematopoietic stem cell transplantation (HSCT) are matched unrelated donors (MUD), unrelated umbilical cord blood (UD-UCB) and one HLA haplotype mismatched family members (haploidentical). The chance of finding a suitable donor in the international voluntary donor registries is limited by frequency of the HLA phenotype and the time required to identify the right donor from a potential panel, to establish eligibility and to harvest the cells. In adult MUD recipients, event-free survival ranges up to 50% and refers only to patients who undergo transplant, without taking into account those who do not find a donor. Umbilical cord blood offers the advantages of easy procurement, the absence of risks to donors, the reduced risk of transmitting infections, immediate availability of cryopreserved samples and acceptance of mismatches at two of the six antigens. Although UD-UCB transplantation is a viable option for children, it is seldom considered for adults. The great divergency between body weight and the number of hematopoietic cells in a standard cord blood unit, particularly if associated with a two-antigen mismatch, increases the risk of graft failure and delays hematopoietic reconstitution. Work on full-haplotype mismatched transplants has been proceeding for over 20 years. Originally, outcome in leukemia patients was disappointing because of high incidence of severe graft-vs.-host disease in T-replete transplants and high rejection rates in T-cell-depleted transplants. The breakthrough came with the use of a megadose of T-cell-depleted progenitor cells after a high-intensity conditioning regimen. Treating end-stage patients inevitably confounded clinical outcome in the early pilot studies. Today, high-risk acute leukemia patients are treated at less advanced stages of disease, receive a reasonably well tolerated conditioning

  17. Growth of melanocytes in human epidermal cell cultures

    SciTech Connect

    Staiano-Coico, L.; Hefton, J.M.; Amadeo, C.; Pagan-Charry, I.; Madden, M.R.; Cardon-Cardo, C. )

    1990-08-01

    Epidermal cell cultures were grown in keratinocyte-conditioned medium for use as burn wound grafts; the melanocyte composition of the grafts was studied under a variety of conditions. Melanocytes were identified by immunohistochemistry based on a monoclonal antibody (MEL-5) that has previously been shown to react specifically with melanocytes. During the first 7 days of growth in primary culture, the total number of melanocytes in the epidermal cultures decreased to 10% of the number present in normal skin. Beginning on day 2 of culture, bipolar melanocytes were present at a mean cell density of 116 +/- 2/mm2; the keratinocyte to melanocyte ratio was preserved during further primary culture and through three subpassages. Moreover, exposure of cultures to mild UVB irradiation stimulated the melanocytes to proliferate, suggesting that the melanocytes growing in culture maintained their responsiveness to external stimuli. When the sheets of cultured cells were enzymatically detached from the plastic culture flasks before grafting, melanocytes remained in the basal layer of cells as part of the graft applied to the patient.

  18. STEM?!?!

    ERIC Educational Resources Information Center

    Merrill, Jen

    2012-01-01

    The author's son has been an engineer since birth. He never asked "why" as a toddler, it was always "how's it work?" So that he wanted a STEM-based home education was no big surprise. In this article, the author considers what kind of curricula would work best for her complex kid.

  19. A 3-D cardiac muscle construct for exploring adult marrow stem cell based myocardial regeneration.

    PubMed

    Valarmathi, Mani T; Goodwin, Richard L; Fuseler, John W; Davis, Jeffrey M; Yost, Michael J; Potts, Jay D

    2010-04-01

    Adult bone marrow stromal cells (BMSCs) are capable of differentiating into cardiomyocyte-like cells in vitro and contribute to myocardial regeneration in vivo. Consequently, BMSCs may potentially play a vital role in cardiac repair and regeneration. However, this concept has been limited by inadequate and inconsistent differentiation of BMSCs into cardiomyocytes along with poor survival and integration of neo-cardiomyocytes after implantation into ischemic myocardium. In order to overcome these barriers and to explore adult stem cell based myocardial regeneration, we have developed an in vitro model of three-dimensional (3-D) cardiac muscle using rat ventricular embryonic cardiomyocytes (ECMs) and BMSCs. When ECMs and BMSCs were seeded sequentially onto a 3-D tubular scaffold engineered from topographically aligned type I collagen-fibers and cultured in basal medium for 7, 14, 21, or 28 days, the maturation and co-differentiation into a cardiomyocyte lineage was observed. Phenotypic induction was characterized at morphological, immunological, biochemical and molecular levels. The observed expression of transcripts coding for cardiomyocyte phenotypic markers and the immunolocalization of cardiomyogenic lineage-associated proteins revealed typical expression patterns of neo-cardiomyogenesis. At the biochemical level differentiating cells exhibited appropriate metabolic activity and at the ultrastructural level myofibrillar and sarcomeric organization were indicative of an immature phenotype. Our 3-D co-culture system sustains the ECMs in vitro continuum of differentiation process and simultaneously induces the maturation and differentiation of BMSCs into cardiomyocyte-like cells. Thus, this novel 3-D co-culture system provides a useful in vitro model to investigate the functional role and interplay of developing ECMs and BMSCs during cardiomyogenic differentiation.

  20. Meis1 Is Required for Adult Mouse Erythropoiesis, Megakaryopoiesis and Hematopoietic Stem Cell Expansion

    PubMed Central

    Miller, Michelle Erin; Rosten, Patty; Lemieux, Madeleine E.; Lai, Courteney; Humphries, R. Keith

    2016-01-01

    Meis1 is recognized as an important transcriptional regulator in hematopoietic development and is strongly implicated in the pathogenesis of leukemia, both as a Hox transcription factor co-factor and independently. Despite the emerging recognition of Meis1’s importance in the context of both normal and leukemic hematopoiesis, there is not yet a full understanding of Meis1’s functions and the relevant pathways and genes mediating its functions. Recently, several conditional mouse models for Meis1 have been established. These models highlight a critical role for Meis1 in adult mouse hematopoietic stem cells (HSCs) and implicate reactive oxygen species (ROS) as a mediator of Meis1 function in this compartment. There are, however, several reported differences between these studies in terms of downstream progenitor populations impacted and effectors of function. In this study, we describe further characterization of a conditional knockout model based on mice carrying a loxP-flanked exon 8 of Meis1 which we crossed onto the inducible Cre localization/expression strains, B6;129-Gt(ROSA)26Sortm1(Cre/ERT)Nat/J or B6.Cg-Tg(Mx1-Cre)1Cgn/J. Findings obtained from these two inducible Meis1 knockout models confirm and extend previous reports of the essential role of Meis1 in adult HSC maintenance and expansion and provide new evidence that highlights key roles of Meis1 in both megakaryopoiesis and erythropoiesis. Gene expression analyses point to a number of candidate genes involved in Meis1’s role in hematopoiesis. Our data additionally support recent evidence of a role of Meis1 in ROS regulation. PMID:26986211

  1. The cardiac stem cell compartment is indispensable for myocardial cell homeostasis, repair and regeneration in the adult.

    PubMed

    Nadal-Ginard, Bernardo; Ellison, Georgina M; Torella, Daniele

    2014-11-01

    Resident cardiac stem cells in embryonic, neonatal and adult mammalian heart have been identified by different membrane markers and transcription factors. However, despite a flurry of publications no consensus has been reached on the identity and actual regenerative effects of the adult cardiac stem cells. Intensive research on the adult mammalian heart's capacity for self-renewal of its muscle cell mass has led to a consensus that new cardiomyocytes (CMs) are indeed formed throughout adult mammalian life albeit at a disputed frequency. The physiological significance of this renewal, the origin of the new CMs, and the rate of adult CM turnover are still highly debated. Myocyte replacement, particularly after injury, was originally attributed to differentiation of a stem cell compartment. More recently, it has been reported that CMs are mainly replaced by the division of pre-existing post-mitotic CMs. These latter results, if confirmed, would shift the target of regenerative therapy toward boosting mature CM cell-cycle re-entry. Despite this controversy, it is documented that the adult endogenous c-kit(pos) cardiac stem cells (c-kit(pos) eCSCs) participate in adaptations to myocardial stress, and, when transplanted into the myocardium, regenerate most cardiomyocytes and microvasculature lost in an infarct. Nevertheless, the in situ myogenic potential of adult c-kit(pos) cardiac cells has been questioned. To revisit the regenerative potential of c-kit(pos) eCSCs, we have recently employed experimental protocols of severe diffuse myocardial damage in combination with several genetic murine models and cell transplantation approaches showing that eCSCs are necessary and sufficient for CM regeneration, leading to complete cellular, anatomical, and functional myocardial recovery. Here we will review the available data on adult eCSC biology and their regenerative potential placing it in the context of the different claimed mechanisms of CM replacement. These data are in

  2. Adenoviral Infections in Adult Allogeneic Hematopoietic Stem Cell Transplant Recipients: A Single Center Experience

    PubMed Central

    Yilmaz, Musa; Chemaly, Roy F.; Han, Xiang Y.; Thall, Peter F.; Fox, Patricia S.; Tarrand, Jeffrey J.; De Lima, Marcos J.; Hosing, Chitra M.; Popat, Uday R.; Shpall, Elizabeth; Champlin, Richard E.; Qazilbash, Muzaffar H.

    2014-01-01

    Disseminated adenoviral infection (AI) is associated with profound immunosuppression and poor outcome after allogeneic hematopoietic stem cell transplantation (allo-HCT). A better understanding of AI in allo-HCT recipients can serve a basis to develop more effective management strategies. We evaluated all adult patients who received allo-HCT at M.D. Anderson Cancer Center between 1999 and 2008. Among the 2879 allo-HCT patients, 73 (2.5%) were diagnosed with AI. Enteritis (26%) and pneumonia (24%) were the most common clinical manifestations; pneumonia was the most common cause of adenovirus-associated death. A multivariable Bayesian logistic regression showed that, when the joint effects of all covariates were accounted for, a cord blood transplant, absolute lymphocyte count (ALC) ≤ 200/mm3, and male gender were associated with a higher probability of disseminated AI. The overall survival was significantly worse for patients with AI that was disseminated rather than localized (median of 5 months versus 28 months, respectively, p<0.001) and for patients with ALC ≤ 200/mm3 (p<0.001). Disseminated AI, in patients who received allo-HCT, is a significant cause of morbidity and mortality. Strategies for early diagnosis and intervention are essential, especially for high-risk patients. PMID:23503529

  3. The Neuropsychological Course of Acute Delirium in Adult Hematopoietic Stem Cell Transplantation Patients

    PubMed Central

    Beglinger, Leigh J.; Mills, James A.; Vik, Stacie M.; Duff, Kevin; Denburg, Natalie L.; Weckmann, Michelle T.; Paulsen, Jane S.; Gingrich, Roger

    2011-01-01

    Although delirium is a common medical comorbidity with altered cognition as its defining feature, few publications have addressed the neuropsychological prodrome, profile, and recovery of patients tested during delirium. We characterize neuropsychological performance in 54 hemapoietic stem cell/bone marrow transplantation (BMT) patients shortly before, during, and after delirium and in BMT patients without delirium and 10 healthy adults. Patients were assessed prospectively before and after transplantation using a brief battery. BMT patients with delirium performed more poorly than comparisons and those without delirium on cross-sectional and trend analyses. Deficits were in expected areas of attention and memory, but also in psychomotor speed and learning. The patients with delirium did not return to normative “average” on any test during observation. Most tests showed a mild decline in the visit before delirium, a sharp decline with delirium onset, and variable performance in the following days. This study adds to the few investigations of neuropsychological performance surrounding delirium and provides targets for monitoring and early detection; Trails A and B, RBANS Coding, and List Recall may be useful for delirium assessment. PMID:21183605

  4. Cellular and molecular dissection of pluripotent adult somatic stem cells in planarians.

    PubMed

    Shibata, Norito; Rouhana, Labib; Agata, Kiyokazu

    2010-01-01

    Freshwater planarians, Plathelminthes, have been an intriguing model animal of regeneration studies for more than 100 years. Their robust regenerative ability is one of asexual reproductive capacity, in which complete animals develop from tiny body fragments within a week. Pluripotent adult somatic stem cells, called neoblasts, assure this regenerative ability. Neoblasts give rise to not only all types of somatic cells, but also germline cells. During the last decade, several experimental techniques for the analysis of planarian neoblasts at the molecular level, such as in situ hybridization, RNAi and fluorescence activated cell sorting, have been established. Moreover, information about genes involved in maintenance and differentiation of neoblasts has been accumulated. One of the molecular features of neoblasts is the expression of many RNA regulators, which are involved in germline development in other animals, such as vasa and piwi family genes. In this review, we introduce physiological and molecular features of the neoblast, and discuss how germline genes regulate planarian neoblasts and what differences exist between neoblasts and germline cells.

  5. Heterogeneity of chromatoid bodies in adult pluripotent stem cells of planarian Dugesia japonica.

    PubMed

    Kashima, Makoto; Kumagai, Nobuyoshi; Agata, Kiyokazu; Shibata, Norito

    2016-02-01

    The robust regenerative ability of planarians is known to be dependent on adult pluripotent stem cells called neoblasts. One of the morphological features of neoblasts is cytoplasmic ribonucleoprotein granules (chromatoid bodies: CBs), which resemble germ granules present in germline cells in other animals. Previously, we showed by immuno-electron microscopic analysis that DjCBC-1, a planarian Me31B/Dhh1/DDX6 homologue, which is a component of ribonucleoprotein granules, was localized in CBs in the planarian Dugesia japonica. Also, recently it was reported using another planarian species that Y12 antibody recognizing symmetrical dimethylarginine (sDMA) specifically binds to CBs in which histone mRNA is co-localized. Here, we showed by double immunostaining and RNA interference (RNAi) that DjCBC-1-containing CBs and Y12-immunoreactive CBs are distinct structures, suggesting that CBs are composed of heterogeneous populations. We also found that the Y12-immunoreactive CBs specifically contained a cytoplasmic type of planarian PIWI protein (DjPiwiC). We revealed by RNAi experiments that Y12-immunoreactive CBs may have anti-transposable element activity involving the DjPiwiC protein in the neoblasts.

  6. Ethical and Regulatory Challenges with Autologous Adult Stem Cells: A Comparative Review of International Regulations.

    PubMed

    Lysaght, Tamra; Kerridge, Ian H; Sipp, Douglas; Porter, Gerard; Capps, Benjamin J

    2017-02-28

    Cell and tissue-based products, such as autologous adult stem cells, are being prescribed by physicians across the world for diseases and illnesses that they have neither been approved for or been demonstrated as safe and effective in formal clinical trials. These doctors often form part of informal transnational networks that exploit differences and similarities in the regulatory systems across geographical contexts. In this paper, we examine the regulatory infrastructure of five geographically diverse but socio-economically comparable countries with the aim of identifying similarities and differences in how these products are regulated and governed within clinical contexts. We find that while there are many subtle technical differences in how these regulations are implemented, they are sufficiently similar that it is difficult to explain why these practices appear more prevalent in some countries and not in others. We conclude with suggestions for how international governance frameworks might be improved to discourage the exploitation of vulnerable patient populations while enabling innovation in the clinical application of cellular therapies.

  7. Ethical issues of unrelated hematopoietic stem cell transplantation in adult thalassemia patients

    PubMed Central

    2011-01-01

    Background Beta thalassemia major is a severe inherited form of hemolytic anemia that results from ineffective erythropoiesis. Allogenic hematopoietic stem cell transplantation (HSCT) remains the only potentially curative therapy. Unfortunately, the subgroup of adult thalassemia patients with hepatomegaly, portal fibrosis and a history of irregular iron chelation have an elevated risk for transplantation-related mortality that is currently estimated to be about 29 percent. Discussion Thalassemia patients may be faced with a difficult choice: they can either continue conventional transfusion and iron chelation therapy or accept the high mortality risk of HSCT in the hope of obtaining complete recovery. Throughout the decision making process, every effort should be made to sustain and enhance autonomous choice. The concept of conscious consent becomes particularly important. The patient must be made fully aware of the favourable and adverse outcomes of HSCT. Although it is the physician's duty to illustrate the possibility of completely restoring health, considerable emphasis should be put on the adverse effects of the procedure. The physician also needs to decide whether the patient is eligible for HSCT according to the "rule of descending order". The patient must be given full details on self-care and fundamental lifestyle changes and be fully aware that he/she will be partly responsible for the outcome. Summary Only if all the aforesaid conditions are satisfied can it be considered reasonable to propose unrelated HSCT as a potential cure for high risk thalassemia patients. PMID:21385429

  8. [Stem-cell leukoses in the adult age--a clinical study].

    PubMed

    Trux, F; Fink, R; Wutke, K

    1977-10-01

    The cytochemical differentiation of 86 stem cell leucoses of adults resulted with 74% of the cases in a clear prevalence of PAS-negative forms at this age. PAS-positive leucoses were observed only in 11%. The survival time of the patients revealed a clear dependence of the degree of the remission achieved. Also for the cases of PAS-negative leucoses, which achieved a complete remission, it was not worse than the survival time of acute lymphoplastic leucoses. However, the remission coefficient of the PAS-negative leucoses was essentially below the value of lymphoblastic forms. Multiple cytostatic combinations reached the best remission rates. Above all the combination of ribidomycin, cytosine arabinosid (Alexan), 6-mercaptopurine (Mercaleukin), prednisolone and vincristine (Oncovin), called RAMPO-scheme by the authors, seemed to give much success according to the results of this study. The number of complete and good partial remissions was calculated with 62% for the ViDaP-scheme, with 51% for the COAP-scheme. For all cases of treatment the coefficient of remission was 54%.

  9. Allogeneic stem cell transplant for adults with myelodysplastic syndromes: relevance of pre-transplant disease status.

    PubMed

    Busca, Alessandro; Pecoraro, Clara; Giaccone, Luisa; Bruno, Benedetto; Allione, Bernardino; Corsetti, Maria Teresa; Pini, Massimo; Marmont, Filippo; Audisio, Ernesta; D'Ardia, Stefano; Frairia, Chiara; Castiglione, Anna; Ciccone, Giovannino; Levis, Alessandro; Vitolo, Umberto; Falda, Michele

    2014-04-01

    The aim of the present study was to investigate the outcome of 94 adult patients with myelodysplasia (MDS) who received an allogeneic stem cell transplant between January 1995 and September 2010 in two Italian hematology centers. At the time of transplant, 53 patients (56%) had relapsed/refractory disease. The cumulative incidence of grades II-IV acute graft-versus-host disease (GVHD) and chronic GVHD was 33% (95% confidence interval [CI] 21-45%) and 78% (95% CI 66-90%), respectively. The cumulative incidence of transplant-related mortality (TRM) at 100 days was 13% (95% CI 6-21%). The 2-year progression free survival (PFS) and overall survival (OS) were 41% (95% CI 31-51%) and 49% (95% CI 38-59%), respectively. On multivariate analysis, advanced disease stage at transplant was the major independent variable associated with an inferior 2-year PFS (HR 3.66, 95% CI 1.98-6.76) and OS (HR 3.68, 95% CI 1.95-6.93). Use of an alternative donor was an independent variable associated with TRM (HR 3.18, 95% CI 1.31-7.72). In conclusion, our data suggest that disease status at the time of transplant is the major predictor for improved PFS and OS, and treatments required to reach this goal may have value in leading to an improved outcome.

  10. Tissue-specific mutation accumulation in human adult stem cells during life

    NASA Astrophysics Data System (ADS)

    Blokzijl, Francis; de Ligt, Joep; Jager, Myrthe; Sasselli, Valentina; Roerink, Sophie; Sasaki, Nobuo; Huch, Meritxell; Boymans, Sander; Kuijk, Ewart; Prins, Pjotr; Nijman, Isaac J.; Martincorena, Inigo; Mokry, Michal; Wiegerinck, Caroline L.; Middendorp, Sabine; Sato, Toshiro; Schwank, Gerald; Nieuwenhuis, Edward E. S.; Verstegen, Monique M. A.; van der Laan, Luc J. W.; de Jonge, Jeroen; Ijzermans, Jan N. M.; Vries, Robert G.; van de Wetering, Marc; Stratton, Michael R.; Clevers, Hans; Cuppen, Edwin; van Boxtel, Ruben

    2016-10-01

    The gradual accumulation of genetic mutations in human adult stem cells (ASCs) during life is associated with various age-related diseases, including cancer. Extreme variation in cancer risk across tissues was recently proposed to depend on the lifetime number of ASC divisions, owing to unavoidable random mutations that arise during DNA replication. However, the rates and patterns of mutations in normal ASCs remain unknown. Here we determine genome-wide mutation patterns in ASCs of the small intestine, colon and liver of human donors with ages ranging from 3 to 87 years by sequencing clonal organoid cultures derived from primary multipotent cells. Our results show that mutations accumulate steadily over time in all of the assessed tissue types, at a rate of approximately 40 novel mutations per year, despite the large variation in cancer incidence among these tissues. Liver ASCs, however, have different mutation spectra compared to those of the colon and small intestine. Mutational signature analysis reveals that this difference can be attributed to spontaneous deamination of methylated cytosine residues in the colon and small intestine, probably reflecting their high ASC division rate. In liver, a signature with an as-yet-unknown underlying mechanism is predominant. Mutation spectra of driver genes in cancer show high similarity to the tissue-specific ASC mutation spectra, suggesting that intrinsic mutational processes in ASCs can initiate tumorigenesis. Notably, the inter-individual variation in mutation rate and spectra are low, suggesting tissue-specific activity of common mutational processes throughout life.

  11. Genetic regulators of a pluripotent adult stem cell system in planarians identified by RNAi and clonal analysis.

    PubMed

    Wagner, Daniel E; Ho, Jaclyn J; Reddien, Peter W

    2012-03-02

    Pluripotency is a central, well-studied feature of embryonic development, but the role of pluripotent cell regulation in somatic tissue regeneration remains poorly understood. In planarians, regeneration of entire animals from tissue fragments is promoted by the activity of adult pluripotent stem cells (cNeoblasts). We utilized transcriptional profiling to identify planarian genes expressed in adult proliferating, regenerative cells (neoblasts). We also developed quantitative clonal analysis methods for expansion and differentiation of cNeoblast descendants that, together with RNAi, revealed gene roles in stem cell biology. Genes encoding two zinc finger proteins, Vasa, a LIM domain protein, Sox and Jun-like transcription factors, two candidate RNA-binding proteins, a Setd8-like protein, and PRC2 (Polycomb) were required for proliferative expansion and/or differentiation of cNeoblast-derived clones. These findings suggest that planarian stem cells utilize molecular mechanisms found in germ cells and other pluripotent cell types and identify genetic regulators of the planarian stem cell system.

  12. In vivo sensitivity of the embryonic and adult neural stem cell compartments to low-dose radiation

    PubMed Central

    Barazzuol, Lara; Jeggo, Penny A.

    2016-01-01

    The embryonic brain is radiation-sensitive, with cognitive deficits being observed after exposure to low radiation doses. Exposure of neonates to radiation can cause intracranial carcinogenesis. To gain insight into the basis underlying these outcomes, we examined the response of the embryonic, neonatal and adult brain to low-dose radiation, focusing on the neural stem cell compartments. This review summarizes our recent findings. At E13.5–14.5 the embryonic neocortex encompasses rapidly proliferating stem and progenitor cells. Exploiting mice with a hypomorphic mutation in DNA ligase IV (Lig4Y288C), we found a high level of DNA double-strand breaks (DSBs) at E14.5, which we attribute to the rapid proliferation. We observed endogenous apoptosis in Lig4Y288C embryos and in WT embryos following exposure to low radiation doses. An examination of DSB levels and apoptosis in adult neural stem cell compartments, the subventricular zone (SVZ) and the subgranular zone (SGZ) revealed low DSB levels in Lig4Y288C mice, comparable with the levels in differentiated neuronal tissues. We conclude that the adult SVZ does not incur high levels of DNA breakage, but sensitively activates apoptosis; apoptosis was less sensitively activated in the SGZ, and differentiated neuronal tissues did not activate apoptosis. P5/P15 mice showed intermediate DSB levels, suggesting that DSBs generated in the embryo can be transmitted to neonates and undergo slow repair. Interestingly, this analysis revealed a stage of high endogenous apoptosis in the neonatal SVZ. Collectively, these studies reveal that the adult neural stem cell compartment, like the embryonic counterpart, can sensitively activate apoptosis. PMID:27125639

  13. Expression of polysialylated neural cell adhesion molecules on adult stem cells after neuronal differentiation of inner ear spiral ganglion neurons

    SciTech Connect

    Park, Kyoung Ho; Yeo, Sang Won; Troy, Frederic A.

    2014-10-17

    Highlights: • PolySia expressed on neurons primarily during early stages of neuronal development. • PolySia–NCAM is expressed on neural stem cells from adult guinea pig spiral ganglion. • PolySia is a biomarker that modulates neuronal differentiation in inner ear stem cells. - Abstract: During brain development, polysialylated (polySia) neural cell adhesion molecules (polySia–NCAMs) modulate cell–cell adhesive interactions involved in synaptogenesis, neural plasticity, myelination, and neural stem cell (NSC) proliferation and differentiation. Our findings show that polySia–NCAM is expressed on NSC isolated from adult guinea pig spiral ganglion (GPSG), and in neurons and Schwann cells after differentiation of the NSC with epidermal, glia, fibroblast growth factors (GFs) and neurotrophins. These differentiated cells were immunoreactive with mAb’s to polySia, NCAM, β-III tubulin, nestin, S-100 and stained with BrdU. NSC could regenerate and be differentiated into neurons and Schwann cells. We conclude: (1) polySia is expressed on NSC isolated from adult GPSG and on neurons and Schwann cells differentiated from these NSC; (2) polySia is expressed on neurons primarily during the early stage of neuronal development and is expressed on Schwann cells at points of cell–cell contact; (3) polySia is a functional biomarker that modulates neuronal differentiation in inner ear stem cells. These new findings suggest that replacement of defective cells in the inner ear of hearing impaired patients using adult spiral ganglion neurons may offer potential hope to improve the quality of life for patients with auditory dysfunction and impaired hearing disorders.

  14. Intrastriatal transplantation of adult human neural crest-derived stem cells improves functional outcome in parkinsonian rats.

    PubMed

    Müller, Janine; Ossig, Christiana; Greiner, Johannes F W; Hauser, Stefan; Fauser, Mareike; Widera, Darius; Kaltschmidt, Christian; Storch, Alexander; Kaltschmidt, Barbara

    2015-01-01

    Parkinson's disease (PD) is considered the second most frequent and one of the most severe neurodegenerative diseases, with dysfunctions of the motor system and with nonmotor symptoms such as depression and dementia. Compensation for the progressive loss of dopaminergic (DA) neurons during PD using current pharmacological treatment strategies is limited and remains challenging. Pluripotent stem cell-based regenerative medicine may offer a promising therapeutic alternative, although the medical application of human embryonic tissue and pluripotent stem cells is still a matter of ethical and practical debate. Addressing these challenges, the present study investigated the potential of adult human neural crest-derived stem cells derived from the inferior turbinate (ITSCs) transplanted into a parkinsonian rat model. Emphasizing their capability to give rise to nervous tissue, ITSCs isolated from the adult human nose efficiently differentiated into functional mature neurons in vitro. Additional successful dopaminergic differentiation of ITSCs was subsequently followed by their transplantation into a unilaterally lesioned 6-hydroxydopamine rat PD model. Transplantation of predifferentiated or undifferentiated ITSCs led to robust restoration of rotational behavior, accompanied by significant recovery of DA neurons within the substantia nigra. ITSCs were further shown to migrate extensively in loose streams primarily toward the posterior direction as far as to the midbrain region, at which point they were able to differentiate into DA neurons within the locus ceruleus. We demonstrate, for the first time, that adult human ITSCs are capable of functionally recovering a PD rat model.

  15. Therapeutic Strategies for Oxidative Stress-Related Cardiovascular Diseases: Removal of Excess Reactive Oxygen Species in Adult Stem Cells.

    PubMed

    Kim, Hyunyun; Yun, Jisoo; Kwon, Sang-Mo

    Accumulating evidence indicates that acute and chronic uncontrolled overproduction of oxidative stress-related factors including reactive oxygen species (ROS) causes cardiovascular diseases (CVDs), atherosclerosis, and diabetes. Moreover ROS mediate various signaling pathways underlying vascular inflammation in ischemic tissues. With respect to stem cell-based therapy, several studies clearly indicate that modulating antioxidant production at cellular levels enhances stem/progenitor cell functionalities, including proliferation, long-term survival in ischemic tissues, and complete differentiation of transplanted cells into mature vascular cells. Recently emerging therapeutic strategies involving adult stem cells, including endothelial progenitor cells (EPCs), for treating ischemic CVDs have highlighted the need to control intracellular ROS production, because it critically affects the replicative senescence of ex vivo expanded therapeutic cells. Better understanding of the complexity of cellular ROS in stem cell biology might improve cell survival in ischemic tissues and enhance the regenerative potentials of transplanted stem/progenitor cells. In this review, we will discuss the nature and sources of ROS, drug-based therapeutic strategies for scavenging ROS, and EPC based therapeutic strategies for treating oxidative stress-related CVDs. Furthermore, we will discuss whether primed EPCs pretreated with natural ROS-scavenging compounds are crucial and promising therapeutic strategies for vascular repair.

  16. Therapeutic Strategies for Oxidative Stress-Related Cardiovascular Diseases: Removal of Excess Reactive Oxygen Species in Adult Stem Cells

    PubMed Central

    Yun, Jisoo

    2016-01-01

    Accumulating evidence indicates that acute and chronic uncontrolled overproduction of oxidative stress-related factors including reactive oxygen species (ROS) causes cardiovascular diseases (CVDs), atherosclerosis, and diabetes. Moreover ROS mediate various signaling pathways underlying vascular inflammation in ischemic tissues. With respect to stem cell-based therapy, several studies clearly indicate that modulating antioxidant production at cellular levels enhances stem/progenitor cell functionalities, including proliferation, long-term survival in ischemic tissues, and complete differentiation of transplanted cells into mature vascular cells. Recently emerging therapeutic strategies involving adult stem cells, including endothelial progenitor cells (EPCs), for treating ischemic CVDs have highlighted the need to control intracellular ROS production, because it critically affects the replicative senescence of ex vivo expanded therapeutic cells. Better understanding of the complexity of cellular ROS in stem cell biology might improve cell survival in ischemic tissues and enhance the regenerative potentials of transplanted stem/progenitor cells. In this review, we will discuss the nature and sources of ROS, drug-based therapeutic strategies for scavenging ROS, and EPC based therapeutic strategies for treating oxidative stress-related CVDs. Furthermore, we will discuss whether primed EPCs pretreated with natural ROS-scavenging compounds are crucial and promising therapeutic strategies for vascular repair. PMID:27668035

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

    PubMed

    Feng, Lijuan; Shi, Zhen; Chen, Xin

    2017-02-01

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

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

    PubMed Central

    Feng, Lijuan; Shi, Zhen; Chen, Xin

    2017-01-01

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

  19. Energy metabolism and energy-sensing pathways in mammalian embryonic and adult stem cell fate

    PubMed Central

    Rafalski, Victoria A.; Mancini, Elena; Brunet, Anne

    2012-01-01

    Summary Metabolism is influenced by age, food intake, and conditions such as diabetes and obesity. How do physiological or pathological metabolic changes influence stem cells, which are crucial for tissue homeostasis? This Commentary reviews recent evidence that stem cells have different metabolic demands than differentiated cells, and that the molecular mechanisms that control stem cell self-renewal and differentiation are functionally connected to the metabolic state of the cell and the surrounding stem cell niche. Furthermore, we present how energy-sensing signaling molecules and metabolism regulators are implicated in the regulation of stem cell self-renewal and differentiation. Finally, we discuss the emerging literature on the metabolism of induced pluripotent stem cells and how manipulating metabolic pathways might aid cellular reprogramming. Determining how energy metabolism regulates stem cell fate should shed light on the decline in tissue regeneration that occurs during aging and facilitate the development of therapies for degenerative or metabolic diseases. PMID:23420198

  20. Mouse embryonic stem cell-derived cells reveal niches that support neuronal differentiation in the adult rat brain.

    PubMed

    Maya-Espinosa, Guadalupe; Collazo-Navarrete, Omar; Millán-Aldaco, Diana; Palomero-Rivero, Marcela; Guerrero-Flores, Gilda; Drucker-Colín, René; Covarrubias, Luis; Guerra-Crespo, Magdalena

    2015-02-01

    A neurogenic niche can be identified by the proliferation and differentiation of its naturally residing neural stem cells. However, it remains unclear whether "silent" neurogenic niches or regions suitable for neural differentiation, other than the areas of active neurogenesis, exist in the adult brain. Embryoid body (EB) cells derived from embryonic stem cells (ESCs) are endowed with a high potential to respond to specification and neuralization signals of the embryo. Hence, to identify microenvironments in the postnatal and adult rat brain with the capacity to support neuronal differentiation, we transplanted dissociated EB cells to conventional neurogenic and non-neurogenic regions. Our results show a neuronal differentiation pattern of EB cells that was dependent on the host region. Efficient neuronal differentiation of EB cells occurred within an adjacent region to the rostral migratory stream. EB cell differentiation was initially patchy and progressed toward an even distribution along the graft by 15-21 days post-transplantation, giving rise mostly to GABAergic neurons. EB cells in the striatum displayed a lower level of neuronal differentiation and derived into a significant number of astrocytes. Remarkably, when EB cells were transplanted to the striatum of adult rats after a local ischemic stroke, increased number of neuroblasts and neurons were observed. Unexpectedly, we determined that the adult substantia nigra pars compacta, considered a non-neurogenic area, harbors a robust neurogenic environment. Therefore, neurally uncommitted cells derived from ESCs can detect regions that support neuronal differentiation within the adult brain, a fundamental step for the development of stem cell-based replacement therapies.

  1. Human embryonic and fetal mesenchymal stem cells differentiate toward three different cardiac lineages in contrast to their adult counterparts.

    PubMed

    Ramkisoensing, Arti A; Pijnappels, Daniël A; Askar, Saïd F A; Passier, Robert; Swildens, Jim; Goumans, Marie José; Schutte, Cindy I; de Vries, Antoine A F; Scherjon, Sicco; Mummery, Christine L; Schalij, Martin J; Atsma, Douwe E

    2011-01-01

    Mesenchymal stem cells (MSCs) show unexplained differences in differentiation potential. In this study, differentiation of human (h) MSCs derived from embryonic, fetal and adult sources toward cardiomyocytes, endothelial and smooth muscle cells was investigated. Labeled hMSCs derived from embryonic stem cells (hESC-MSCs), fetal umbilical cord, bone marrow, amniotic membrane and adult bone marrow and adipose tissue were co-cultured with neonatal rat cardiomyocytes (nrCMCs) or cardiac fibroblasts (nrCFBs) for 10 days, and also cultured under angiogenic conditions. Cardiomyogenesis was assessed by human-specific immunocytological analysis, whole-cell current-clamp recordings, human-specific qRT-PCR and optical mapping. After co-culture with nrCMCs, significantly more hESC-MSCs than fetal hMSCs stained positive for α-actinin, whereas adult hMSCs stained negative. Furthermore, functional cardiomyogenic differentiation, based on action potential recordings, was shown to occur, but not in adult hMSCs. Of all sources, hESC-MSCs expressed most cardiac-specific genes. hESC-MSCs and fetal hMSCs contained significantly higher basal levels of connexin43 than adult hMSCs and co-culture with nrCMCs increased expression. After co-culture with nrCFBs, hESC-MSCs and fetal hMSCs did not express α-actinin and connexin43 expression was decreased. Conduction velocity (CV) in co-cultures of nrCMCs and hESC-MSCs was significantly higher than in co-cultures with fetal or adult hMSCs. In angiogenesis bioassays, only hESC-MSCs and fetal hMSCs were able to form capillary-like structures, which stained for smooth muscle and endothelial cell markers.Human embryonic and fetal MSCs differentiate toward three different cardiac lineages, in contrast to adult MSCs. Cardiomyogenesis is determined by stimuli from the cellular microenvironment, where connexin43 may play an important role.

  2. Meningeal Melanocytes in the Mouse: Distribution and Dependence on Mitf

    PubMed Central

    Gudjohnsen, Stefán A. H.; Atacho, Diahann A. M.; Gesbert, Franck; Raposo, Graca; Hurbain, Ilse; Larue, Lionel; Steingrimsson, Eirikur; Petersen, Petur Henry

    2015-01-01

    Summary: Melanocytes are pigment producing cells derived from the neural crest. They are primarily found in the skin and hair follicles, but can also be found in other tissues including the eye, ear and heart. Here, we describe the distribution of pigmented cells in C57BL/6J mouse meninges, the membranes that envelope the brain. These cells contain melanosomes of all four stages of development and they depend on Microphthalmia associated transcription factor (MITF), the master regulator of melanocyte development, suggesting that they are bona-fide melanocytes. The location of these pigmented cells is consistent with the location of meningeal melanomas in humans and animal models. Significance: Here, we document and define pigmented cells in the meninges of the mouse brain and confirm that they are melanocytes. This is important for understanding the role of this cell type and for understanding primary meningeal melanoma, a rare disease that likely arises from normal meningeal melanocytes. PMID:26635543

  3. Detection, Characterization, and Spontaneous Differentiation In Vitro of Very Small Embryonic-Like Putative Stem Cells in Adult Mammalian Ovary

    PubMed Central

    Parte, Seema; Telang, Jyoti; Daithankar, Vinita; Salvi, Vinita; Zaveri, Kusum; Hinduja, Indira

    2011-01-01

    The present study was undertaken to detect, characterize, and study differentiation potential of stem cells in adult rabbit, sheep, monkey, and menopausal human ovarian surface epithelium (OSE). Two distinct populations of putative stem cells (PSCs) of variable size were detected in scraped OSE, one being smaller and other similar in size to the surrounding red blood cells in the scraped OSE. The smaller 1–3 μm very small embryonic-like PSCs were pluripotent in nature with nuclear Oct-4 and cell surface SSEA-4, whereas the bigger 4–7 μm cells with cytoplasmic localization of Oct-4 and minimal expression of SSEA-4 were possibly the tissue committed progenitor stem cells. Pluripotent gene transcripts of Oct-4, Oct-4A, Nanog, Sox-2, TERT, and Stat-3 in human and sheep OSE were detected by reverse transcriptase–polymerase chain reaction. The PSCs underwent spontaneous differentiation into oocyte-like structures, parthenote-like structures, embryoid body-like structures, cells with neuronal-like phenotype, and embryonic stem cell-like colonies, whereas the epithelial cells transformed into mesenchymal phenotype by epithelial–mesenchymal transition in 3 weeks of OSE culture. Germ cell markers like c-Kit, DAZL, GDF-9, VASA, and ZP4 were immuno-localized in oocyte-like structures. In conclusion, as opposed to the existing view of OSE being a bipotent source of oocytes and granulosa cells, mammalian ovaries harbor distinct very small embryonic-like PSCs and tissue committed progenitor stem cells population that have the potential to develop into oocyte-like structures in vitro, whereas mesenchymal fibroblasts appear to form supporting granulosa-like somatic cells. Research at the single-cell level, including complete gene expression profiling, is required to further confirm whether postnatal oogenesis is a conserved phenomenon in adult mammals. PMID:21291304

  4. Detection, characterization, and spontaneous differentiation in vitro of very small embryonic-like putative stem cells in adult mammalian ovary.

    PubMed

    Parte, Seema; Bhartiya, Deepa; Telang, Jyoti; Daithankar, Vinita; Salvi, Vinita; Zaveri, Kusum; Hinduja, Indira

    2011-08-01

    The present study was undertaken to detect, characterize, and study differentiation potential of stem cells in adult rabbit, sheep, monkey, and menopausal human ovarian surface epithelium (OSE). Two distinct populations of putative stem cells (PSCs) of variable size were detected in scraped OSE, one being smaller and other similar in size to the surrounding red blood cells in the scraped OSE. The smaller 1-3 μm very small embryonic-like PSCs were pluripotent in nature with nuclear Oct-4 and cell surface SSEA-4, whereas the bigger 4-7 μm cells with cytoplasmic localization of Oct-4 and minimal expression of SSEA-4 were possibly the tissue committed progenitor stem cells. Pluripotent gene transcripts of Oct-4, Oct-4A, Nanog, Sox-2, TERT, and Stat-3 in human and sheep OSE were detected by reverse transcriptase-polymerase chain reaction. The PSCs underwent spontaneous differentiation into oocyte-like structures, parthenote-like structures, embryoid body-like structures, cells with neuronal-like phenotype, and embryonic stem cell-like colonies, whereas the epithelial cells transformed into mesenchymal phenotype by epithelial-mesenchymal transition in 3 weeks of OSE culture. Germ cell markers like c-Kit, DAZL, GDF-9, VASA, and ZP4 were immuno-localized in oocyte-like structures. In conclusion, as opposed to the existing view of OSE being a bipotent source of oocytes and granulosa cells, mammalian ovaries harbor distinct very small embryonic-like PSCs and tissue committed progenitor stem cells population that have the potential to develop into oocyte-like structures in vitro, whereas mesenchymal fibroblasts appear to form supporting granulosa-like somatic cells. Research at the single-cell level, including complete gene expression profiling, is required to further confirm whether postnatal oogenesis is a conserved phenomenon in adult mammals.

  5. A circuit-based gatekeeper for adult neural stem cell proliferation: Parvalbumin-expressing interneurons of the dentate gyrus control the activation and proliferation of quiescent adult neural stem cells.

    PubMed

    Moss, Jonathan; Toni, Nicolas

    2013-01-01

    Newborn neurons are generated in the adult hippocampus from a pool of self-renewing stem cells located in the subgranular zone (SGZ) of the dentate gyrus. Their activation, proliferation, and maturation depend on a host of environmental and cellular factors but, until recently, the contribution of local neuronal circuitry to this process was relatively unknown. In their recent publication, Song and colleagues have uncovered a novel circuit-based mechanism by which release of the neurotransmitter, γ-aminobutyric acid (GABA), from parvalbumin-expressing (PV) interneurons, can hold radial glia-like (RGL) stem cells of the adult SGZ in a quiescent state. This tonic GABAergic signal, dependent upon the activation of γ(2) subunit-containing GABA(A) receptors of RGL stem cells, can thus prevent their proliferation and subsequent maturation or return them to quiescence if previously activated. PV interneurons are thus capable of suppressing neurogenesis during periods of high network activity and facilitating neurogenesis when network activity is low.

  6. Running rescues defective adult neurogenesis by shortening the length of the cell cycle of neural stem and progenitor cells.

    PubMed

    Farioli-Vecchioli, Stefano; Mattera, Andrea; Micheli, Laura; Ceccarelli, Manuela; Leonardi, Luca; Saraulli, Daniele; Costanzi, Marco; Cestari, Vincenzo; Rouault, Jean-Pierre; Tirone, Felice

    2014-07-01

    Physical exercise increases the generation of new neurons in adult neurogenesis. However, only few studies have investigated the beneficial effects of physical exercise in paradigms of impaired neurogenesis. Here, we demonstrate that running fully reverses the deficient adult neurogenesis within the hippocampus and subventricular zone of the lateral ventricle, observed in mice lacking the antiproliferative gene Btg1. We also evaluated for the first time how running influences the cell cycle kinetics of stem and precursor subpopulations of wild-type and Btg1-null mice, using a new method to determine the cell cycle length. Our data show that in wild-type mice running leads to a cell cycle shortening only of NeuroD1-positive progenitor cells. In contrast, in Btg1-null mice, physical exercise fully reactivates the defective hippocampal neurogenesis, by shortening the S-phase length and the overall cell cycle duration of both neural stem (glial fibrillary acidic protein(+) and Sox2(+)) and progenitor (NeuroD1(+)) cells. These events are sufficient and necessary to reactivate the hyperproliferation observed in Btg1-null early-postnatal mice and to expand the pool of adult neural stem and progenitor cells. Such a sustained increase of cell proliferation in Btg1-null mice after running provides a long-lasting increment of proliferation, differentiation, and production of newborn neurons, which rescues the impaired pattern separation previously identified in Btg1-null mice. This study shows that running positively affects the cell cycle kinetics of specific subpopulations of newly generated neurons and suggests that the plasticity of neural stem cells without cell cycle inhibitory control is reactivated by running, with implications for the long-term modulation of neurogenesis.

  7. Exosomes released by keratinocytes modulate melanocyte pigmentation

    PubMed Central

    Cicero, Alessandra Lo; Delevoye, Cédric; Gilles-Marsens, Floriane; Loew, Damarys; Dingli, Florent; Guéré, Christelle; André, Nathalie; Vié, Katell; van Niel, Guillaume; Raposo, Graça

    2015-01-01

    Cells secrete extracellular vesicles (EVs), exosomes and microvesicles, which transfer proteins, lipids and RNAs to regulate recipient cell functions. Skin pigmentation relies on a tight dialogue between keratinocytes and melanocytes in the epidermis. Here we report that exosomes secreted by keratinocytes enhance melanin synthesis by increasing both the expression and activity of melanosomal proteins. Furthermore, we show that the function of keratinocyte-derived exosomes is phototype-dependent and is modulated by ultraviolet B. In sum, this study uncovers an important physiological function for exosomes in human pigmentation and opens new avenues in our understanding of how pigmentation is regulated by intercellular communication in both healthy and diseased states. PMID:26103923

  8. Exosomes released by keratinocytes modulate melanocyte pigmentation.

    PubMed

    Lo Cicero, Alessandra; Delevoye, Cédric; Gilles-Marsens, Floriane; Loew, Damarys; Dingli, Florent; Guéré, Christelle; André, Nathalie; Vié, Katell; van Niel, Guillaume; Raposo, Graça

    2015-06-24

    Cells secrete extracellular vesicles (EVs), exosomes and microvesicles, which transfer proteins, lipids and RNAs to regulate recipient cell functions. Skin pigmentation relies on a tight dialogue between keratinocytes and melanocytes in the epidermis. Here we report that exosomes secreted by keratinocytes enhance melanin synthesis by increasing both the expression and activity of melanosomal proteins. Furthermore, we show that the function of keratinocyte-derived exosomes is phototype-dependent and is modulated by ultraviolet B. In sum, this study uncovers an important physiological function for exosomes in human pigmentation and opens new avenues in our understanding of how pigmentation is regulated by intercellular communication in both healthy and diseased states.

  9. Gene delivery techniques for adult stem cell-based regenerative therapy.

    PubMed

    Seo, Seog-Jin; Kim, Tae-Hyun; Choi, Seong-Jun; Park, Jeong-Hui; Wall, Ivan B; Kim, Hae-Won

    2013-11-01

    Over the past decade, stem cells have been considered to be a promising resource to cure and regenerate damaged or diseased tissues with research extending from basic studies to clinical application. Furthermore, genetically modified stem cells have the potential to reduce tumorigenic risks and achieve safe tissue formation. Recent advances in genetic modification of stem cells have rendered these cells more accessible and stable. The successful genetic modification of stem cells relies heavily on designing vector systems, either viral or nonviral vectors, which can efficiently deliver therapeutic genes to the cells with minimum toxicity. Currently, viral vectors showing high transfection efficiencies still raise safety issues, whereas safer nonviral vectors exhibit extremely poor transfection in stem cells. Here, we attempt to review and discuss the main factors raising concern in previous reports, and devise strategies to solve the issues in gene delivery systems for successful stem cell-targeting regenerative therapy.

  10. Effects of hydroxybenzyl alcohols on melanogenesis in melanocyte-keratinocyte co-culture and monolayer culture of melanocytes.

    PubMed

    Liu, Szu-Hsiu; Chu, I-Ming; Pan, I-Horng

    2008-08-01

    In mammalian skin, melanocyte proliferation and melanogenesis can be stimulated by keratinocytes, fibroblasts and other regulatory factors. To determine whether hydroxybenzyl alcohols (HBAs) show more inhibitory in melanocytes cultured alone or in melanocytes co-cultured with keratinocytes, we developed a murine melanocyte-keratinocyte co-culture model to investigate the pigmentation regulators in company with other melanogenic inhibitors and stimulators. It was found that the effects of HBAs and melanogenic factors were more evident in melanocytes co-cultured with keratinocytes. Keratinocytes may play a synergistic role in melanocyte melanogenesis and influence the pigment production. The tests in the co-culture model also imply that the inhibitory effects of HBAs on melanogenesis are due to the direct inhibition of melanosomal tyrosinase activity. HBAs showed a low cytotoxicity. The eventual results proved that HBAs are promising and safe agents for skin whitening in melanocyte alone and in co-culture systems. The co-culture model provides a more physiologically realistic condition to study the interaction between melanocytes and keratinocytes, which enables a reliable screening system for depigmenting compounds.

  11. Exploring the Cancer Experiences of Young Adults in the Context of Stem Cell Transplantation

    PubMed Central

    Brassil, Kelly J; Engebretson, Joan C; Armstrong, Terri S; Segovia, Julie; Worth, Laura L; Summers, Barbara L

    2014-01-01

    Background Cancer is the leading cause of non-accidental morbidity and mortality among young adults (YAs) in the United States. Stem cell transplantation (SCT), a treatment modality for a variety of YA malignancies, often requires prolonged hospitalization and immune-compromising treatment regimens. SCT may isolate YAs physically and emotionally, contributing to uncertainty about treatment processes, outcomes, and long-term sequelae. Studies in this population suggest that uncertainty can contribute to difficulty accomplishing basic developmental tasks. Few studies have examined the experiences of YAs in active cancer treatment, particularly those undergoing SCT. Objectives This study explored the cancer experiences of YAs age 18-25 leading up to SCT and explored how YAs construct issues of uncertainty related to the transplantation experience. Methods Interviews with 14 YAs conducted within 24 hours of admission to undergo SCT were analyzed using thematic analysis from a medical ethnographic perspective. Results Themes emerged within two domains: relational and psycho-emotional. The relational theme of “altered relationships” included subthemes of “moving from” and “moving toward.” The psycho-emotional theme of the “power of perspective” included subthemes of “optimism,” “acknowledgment of death,” “informational empowerment,” and “developing a new outlook.” Conclusions Our findings offer new insights into the YA experience in the context of active cancer treatment, specifically how the cancer experience impacts relationships, and how this experience is influenced by YAs' perspectives. Implications for Practice This study provides a foundation for addressing the psycho-social needs of YAs hospitalized for SCT, paying particular attention to the development of specific interventions. PMID:25232959

  12. [Vaccination of adult patients receiving hematopoietic stem cell transplantation: Perspective of Costa Rica].

    PubMed

    Espínoza Mora, M Del Rosario; Lazo Páez, Gustavo; León Bratti, M Paz; Schauer, Christian

    2016-12-01

    In this article the present recommendations for immunization of adult patients who received hematopoietic stem cell transplantation -a common procedure in therapy of many types of hematological diseases and serious inborn defects of the immune system- are reviewed and discussed. Patients that undergo this kind of transplantation procedure exhibit, compared to the general population, an elevated susceptibility of immune-preventable infections, due to loss of the humoral and cellular protective immunity. A revaccination strategy for transplanted patients can result in a significant diminution of morbidity and mortality related to the treatment of these diseases. Few data are published about the duration and magnitude of the vaccination response in this specific population of patients. Moreover, deviation from international guidelines recommendations for post-transplant immune prophylaxis can be observed frequently, partly as a result of the absence of specific vaccines in some countries. Multiple factors as intensity of the pharmacologic immune suppression, myeloablative regimen, administration of monoclonal and polyclonal antibodies, duration of the post-transplant period or the presence of graft-versus-host disease (GVHD), can influence the immune response and establish special considerations for certain biological agents, as observed in case of living attenuated virus composed vaccines. This conditions are responsible for the fact that an optimal time point for vaccination of transplanted patients remains not clearly defined. More specific studies about the underlying immunological mechanisms during immunocompromised periods are necessary to understand better the immunogenicity and security of existing vaccines. The development of innovative vaccines as well can induce certain advances in the post-transplant therapy.

  13. Pituitary Adenlylate Cyclase Activating Peptide Protects Adult Neural Stem Cells from a Hypoglycaemic milieu

    PubMed Central

    Mansouri, Shiva; Lietzau, Grazyna; Lundberg, Mathias; Nathanson, David; Nyström, Thomas; Patrone, Cesare

    2016-01-01

    Hypoglycaemia is a common side-effect of glucose-lowering therapies for type-2 diabetic patients, which may cause cognitive/neurological impairment. Although the effects of hypoglycaemia in the brain have been extensively studied in neurons, how hypoglycaemia impacts the viability of adult neural stem cells (NSCs) has been poorly investigated. In addition, the cellular and molecular mechanisms of how hypoglycaemia regulates NSCs survival have not been characterized. Recent work others and us have shown that the pituitary adenylate cyclase-activating polypeptide (PACAP) and the glucagon-like peptide-1 receptor (GLP-1R) agonist Exendin-4 stimulate NSCs survival against glucolipoapoptosis. The aim of this study was to establish an in vitro system where to study the effects of hypoglycaemia on NSC survival. Furthermore, we determine the potential role of PACAP and Exendin-4 in counteracting the effect of hypoglycaemia. A hypoglycaemic in vitro milieu was mimicked by exposing subventricular zone-derived NSC to low levels of glucose. Moreover, we studied the potential involvement of apoptosis and endoplasmic reticulum stress by quantifying protein levels of Bcl-2, cleaved caspase-3 and mRNA levels of CHOP. We show that PACAP via PAC-1 receptor and PKA activation counteracts impaired NSC viability induced by hypoglycaemia. The protective effect induced by PACAP correlated with endoplasmic reticulum stress, Exendin-4 was ineffective. The results show that hypoglycaemia decreases NSC viability and that this effect can be substantially counteracted by PACAP via PAC-1 receptor activation. The data supports a potential therapeutic role of PAC-1 receptor agonists for the treatment of neurological complications, based on neurogenesis impairment by hypoglycaemia. PMID:27305000

  14. Microenvironmental determinants of adult neural stem cell proliferation and lineage commitment in the healthy and injured central nervous system.

    PubMed

    Moyse, Emmanuel; Segura, Stéphanie; Liard, Oliver; Mahaut, Stéphanie; Mechawar, Naguib

    2008-09-01

    The discovery of neural stem cells (NSC) which ensure continuous neurogenesis in the adult mammalian brain, has led to a conceptual revolution in basic neuroscience and to high hopes for clinical nervous tissue repair. However, several research issues remain to address before neural stem cells can be harnessed for regenerative therapies. The presence of NSC in a nervous structure is demonstrated in vitro by primary culture of dissociated adult nervous tissue in the presence of the specific mitogens EGF and bFGF. This leads to spherical masses of proliferating cells endowed with capacities for self-renewal and, after growth factor removal, differentiation into the three characteristic cell types of nervous tissue (neurons, astrocytes, oligodendrocytes). In vivo, neurogenesis per se, i.e. production of new neurons, occurs only in a small subset of NSC-endowed structures. The production of oligodendrocytes, i.e. myelinating glial cells, is similarly restricted. Such in vivo restrictions were formally demonstrated to arise from the tissular microenvironnement, which led to the emerging concept of "neurogenic niche". In this context, major challenges now consist in identifying the nature of tissue-specific extracellular signals that determine lineage commitment of NSC progeny, understanding why NSCs display weak in vivo reactivity to lesions compared to other stem cell types in adults, and identifying the factors behind the very high resistance to tumorigenesis displayed by NSCs. Altogether, the current data offer hope for the future use of adult NSCs in regenerative therapies, provided that tissue-specific signals are identified in view of counteracting the intrinsic repression of new cell genesis and/or stimulating endogenous NSC recruitment to lesion sites.

  15. Accumulated quiescent neural stem cells in adult hippocampus of the mouse model for the MECP2 duplication syndrome

    PubMed Central

    Chen, Zhifang; Li, Xiao; Zhou, Jingjing; Yuan, Bo; Yu, Bin; Tong, Dali; Cheng, Cheng; Shao, Yinqi; Xia, Shengnan; Zhang, Ran; Lyu, Jingwen; Yu, Xiuya; Dong, Chen; Zhou, Wen-Hao; Qiu, Zilong

    2017-01-01

    Duplications of Methyl CpG binding protein 2 (MECP2) -containing segments lead to the MECP2 duplication syndrome, in which severe autistic symptoms were identified. Whether adult neurogenesis may play a role in pathogenesis of autism and the role of MECP2 on state determination of adult neural stem cells (NSCs) remain largely unclear. Using a MECP2 transgenic (TG) mouse model for the MECP2 duplication syndrome, we found that adult hippocampal quiescent NSCs were significantly accumulated in TG mice comparing to wild type (WT) mice, the neural progenitor cells (NPCs) were reduced and the neuroblasts were increased in adult hippocampi of MECP2 TG mice. Interestingly, we found that parvalbumin (PV) positive interneurons were significantly decreased in MECP2 TG mice, which were critical for determining fates of adult hippocampal NSCs between the quiescence and activation. In summary, we found that MeCP2 plays a critical role in regulating fate determination of adult NSCs. These evidences further suggest that abnormal development of NSCs may play a role in the pathogenesis of the MECP2 duplication syndrome. PMID:28139724

  16. Adipocyte amino acid sensing controls adult germline stem cell number via the amino acid response pathway and independently of Target of Rapamycin signaling in Drosophila.

    PubMed

    Armstrong, Alissa R; Laws, Kaitlin M; Drummond-Barbosa, Daniela

    2014-12-01

    How adipocytes contribute to the physiological control of stem cells is a critical question towards understanding the link between obesity and multiple diseases, including cancers. Previous studies have revealed that adult stem cells are influenced by whole-body physiology through multiple diet-dependent factors. For example, nutrient-dependent pathways acting within the Drosophila ovary control the number and proliferation of germline stem cells (GSCs). The potential role of nutrient sensing by adipocytes in modulating stem cells in other organs, however, remains largely unexplored. Here, we report that amino acid sensing by adult adipocytes specifically modulates the maintenance of GSCs through a Target of Rapamycin-independent mechanism. Instead, reduced amino acid levels and the consequent increase in uncoupled tRNAs trigger activation of the GCN2-dependent amino acid response pathway within adipocytes, causing increased rates of GSC loss. These studies reveal a new step in adipocyte-stem cell crosstalk.

  17. In Vivo Tumorigenesis Was Observed after Injection of In Vitro Expanded Neural Crest Stem Cells Isolated from Adult Bone Marrow

    PubMed Central

    Neirinckx, Virginie; Hennuy, Benoit; Swingland, James T.; Laudet, Emerence; Sommer, Lukas; Shakova, Olga; Bours, Vincent; Rogister, Bernard

    2012-01-01

    Bone marrow stromal cells are adult multipotent cells that represent an attractive tool in cellular therapy strategies. Several studies have reported that in vitro passaging of mesenchymal stem cells alters the functional and biological properties of those cells, leading to the accumulation of genetic aberrations. Recent studies described bone marrow stromal cells (BMSC) as mixed populations of cells including mesenchymal (MSC) and neural crest stem cells (NCSC). Here, we report the transformation of NCSC into tumorigenic cells, after in vitro long-term passaging. Indeed, the characterization of 6 neural crest-derived clones revealed the presence of one tumorigenic clone. Transcriptomic analyses of this clone highlighted, among others, numerous cell cycle checkpoint modifications and chromosome 11q down-regulation (suggesting a deletion of chromosome 11q) compared with the other clones. Moreover, unsupervised analysis such as a dendrogram generated after agglomerative hierarchical clustering comparing several transcriptomic data showed important similarities between the tumorigenic neural crest-derived clone and mammary tumor cell lines. Altogether, it appeared that NCSC isolated from adult bone marrow represents a potential danger for cellular therapy, and consequently, we recommend that phenotypic, functional and genetic assays should be performed on bone marrow mesenchymal and neural crest stem cells before in vivo use, to demonstrate whether their biological properties, after ex vivo expansion, remain suitable for clinical application. PMID:23071568

  18. The CUL4-DDB1 ubiquitin ligase complex controls adult and embryonic stem cell differentiation and homeostasis

    PubMed Central

    Gao, Jie; Buckley, Shannon M; Cimmino, Luisa; Guillamot, Maria; Strikoudis, Alexandros; Cang, Yong; Goff, Stephen P; Aifantis, Iannis

    2015-01-01

    Little is known on post-transcriptional regulation of adult and embryonic stem cell maintenance and differentiation. Here we characterize the role of Ddb1, a component of the CUL4-DDB1 ubiquitin ligase complex. Ddb1 is highly expressed in multipotent hematopoietic progenitors and its deletion leads to abrogation of both adult and fetal hematopoiesis, targeting specifically transiently amplifying progenitor subsets. However, Ddb1 deletion in non-dividing lymphocytes has no discernible phenotypes. Ddb1 silencing activates Trp53 pathway and leads to significant effects on cell cycle progression and rapid apoptosis. The abrogation of hematopoietic progenitor cells can be partially rescued by simultaneous deletion of Trp53. Conversely, depletion of DDB1 in embryonic stem cell (ESC) leads to differentiation albeit negative effects on cell cycle and apoptosis. Mass spectrometry reveals differing protein interactions between DDB1 and distinct DCAFs, the substrate recognizing components of the E3 complex, between cell types. Our studies identify CUL4-DDB1 complex as a novel post-translational regulator of stem and progenitor maintenance and differentiation. DOI: http://dx.doi.org/10.7554/eLife.07539.001 PMID:26613412

  19. Expression of the Argonaute protein PiwiL2 and piRNAs in adult mouse mesenchymal stem cells

    SciTech Connect

    Wu, Qiuling; Ma, Qi; Shehadeh, Lina A.; Wilson, Amber; Xia, Linghui; Yu, Hong; Webster, Keith A.

    2010-06-11

    Piwi (P-element-induced wimpy testis) first discovered in Drosophila is a member of the Argonaute family of micro-RNA binding proteins with essential roles in germ-cell development. The murine homologue of PiwiL2, also known as Mili is selectively expressed in the testes, and mice bearing targeted mutations of the PiwiL2 gene are male-sterile. PiwiL2 proteins are thought to protect the germ line genome by suppressing retrotransposons, stabilizing heterochromatin structure, and regulating target genes during meiosis and mitosis. Here, we report that PiwiL2 and associated piRNAs (piRs) may play similar roles in adult mouse mesenchymal stem cells. We found that PiwiL2 is expressed in the cytoplasm of metaphase mesenchymal stem cells from the bone marrow of adult and aged mice. Knockdown of PiwiL2 with a specific siRNA enhanced cell proliferation, significantly increased the number of cells in G1/S and G2/M cell cycle phases and was associated with increased expression of cell cycle genes CCND1, CDK8, microtubule regulation genes, and decreased expression of tumor suppressors Cables 1, LATS, and Cxxc4. The results suggest broader roles for Piwi in genome surveillance beyond the germ line and a possible role in regulating the cell cycle of mesenchymal stem cells.

  20. Functional and Molecular Characterization of Rod-like Cells from Retinal Stem Cells Derived from the Adult Ciliary Epithelium

    PubMed Central

    Demontis, Gian Carlo; Aruta, Claudia; Comitato, Antonella; De Marzo, Anna; Marigo, Valeria

    2012-01-01

    In vitro generation of photoreceptors from stem cells is of great interest for the development of regenerative medicine approaches for patients affected by retinal degeneration and for high throughput drug screens for these diseases. In this study, we show unprecedented high percentages of rod-fated cells from retinal stem cells of the adult ciliary epithelium. Molecular characterization of rod-like cells demonstrates that they lose ciliary epithelial characteristics but acquire photoreceptor features. Rod maturation was evaluated at two levels: gene expression and electrophysiological functionality. Here we present a strong correlation between phototransduction protein expression and functionality of the cells in vitro. We demonstrate that in vitro generated rod-like cells express cGMP-gated channels that are gated by endogenous cGMP. We also identified voltage-gated channels necessary for rod maturation and viability. This level of analysis for the first time provides evidence that adult retinal stem cells can generate highly homogeneous rod-fated cells. PMID:22432014

  1. Reelin and its receptors, VLDLR and ApoER2, in melanocytic nevi

    PubMed Central

    Mihail, A; Coman, G; Staniceanu, F; Coman, L; Zurac, S; Coman, OA

    2017-01-01

    Reelin is an extracellular signaling protein synthesized by Cajal-Retius cells in utero and early after birth, its presence being signaled in adult life too. Reelin acts on its receptors, VLDLR and ApoER2, acting on cytoskeleton, controlling migration and subsequently positioning and stabilizing the cortical neurons. We investigated the reelin presence and its receptors, VLDLR and ApoER2, in melanocytic nevi considering the neural crest origin of the nevus cells and their migration into skin during embrionary period. Melanocytic nevi present a strict cellular architecture and an increased malignant transforming capacity. We investigated reelin presence in 32 melanocytic nevi (5 junctional, 27 compound or 14 dysplastic nevi and 18 non dysplastic nevi). The assessment of reelin presence was performed by histological semiquantitative criteria. Results showed the presence of reelin in 29 cases (29/ 32). The presence of reelin was elevated in junctional areas as in dysplastic nevi. VLDLR presented positive values in 16 cases (16/ 32) and ApoER2 was weak positive in 7 cases. Reelin or its receptors was peritumorally absent. Our study showed the presence of reelin in nevus cells from cutaneous melanocytic nevi and, in these cells, only the VLDLR receptor was present in half of the cases. The significance of the reelin presence in cutaneous nevus cells may be hypothetically considered correlated with the position maintenance of the nevus cells or migration of these cells in malignant transforming situation. Abbreviations: ApoER2 = apolipoprotein receptor 2, VLDLR = very low density lipoprotein receptor, DAB-1 = DIABLO protein, HMB45 = gene HMB45 PMID:28255385

  2. Neural stem cell deforestation as the main force driving the age-related decline in adult hippocampal neurogenesis.

    PubMed

    Encinas, Juan M; Sierra, Amanda

    2012-02-14

    Newborn neurons derived from radial glia-like stem cells located in the dentate gyrus integrate into the adult hippocampal circuitry and participate in memory formation, spatial learning, pattern separation, fear conditioning, and anxiety. This process takes place throughout the life span of mammals, including humans; however, it follows a sharp declining curve. New neurons are generated abundantly during youth but very scarcely in the aged brain. The absolute number of newly generated neurons, or neurogenic output, is determined at different levels along the neurogenic cascade: the activation of quiescent stem cells; the mitotic potential of proliferating precursors; and the survival of neuronal fate-committed precursors. A continuous depletion of the hippocampal neural stem cell pool has been recently proposed as the main force underlying the age-related decline of neurogenesis, in contrast to the previous view of population of neural stem cells whose number remains constant but loses its ability to bear fruit. Nevertheless, the diminished neurogenic output may be reflecting other phenomena such as decreased mitotic capability of proliferating progenitors, decreased survival or changes in differentiation. We describe herein the most important events in determining the amount of neurogenesis in the dentate gyrus and examine the literature to understand the effects of age throughout the cascade.

  3. Macrophages Contribute to the Cyclic Activation of Adult Hair Follicle Stem Cells

    PubMed Central

    Castellana, Donatello; Paus, Ralf; Perez-Moreno, Mirna

    2014-01-01

    Skin epithelial stem cells operate within a complex signaling milieu that orchestrates their lifetime regenerative properties. The question of whether and how immune cells impact on these stem cells within their niche is not well understood. Here we show that skin-resident macrophages decrease in number because of apoptosis before the onset of epithelial hair follicle stem cell activation during the murine hair cycle. This process is linked to distinct gene expression, including Wnt transcription. Interestingly, by mimicking this event through the selective induction of macrophage apoptosis in early telogen, we identify a novel involvement of macrophages in stem cell activation in vivo. Importantly, the macrophage-specific pharmacological inhibition of Wnt production delays hair follicle growth. Thus, perifollicular macrophages contribute to the activation of skin epithelial stem cells as a novel, additional cue that regulates their regenerative activity. This finding may have translational implications for skin repair, inflammatory skin diseases and cancer. PMID:25536657

  4. Cyclin E marks quiescent neural stem cells and caspase-3-positive newborn cells during adult hippocampal neurogenesis in mice.

    PubMed

    Ikeda, Yayoi; Ikeda, Masa-Aki

    2015-10-21

    Cyclin E is a key regulator of progression through the G1-phase of the cell cycle. Recently, a cell cycle-independent role for cyclin E in the adult mouse central nervous system has been suggested. In the present study, we examined expression of cyclin E in the mouse hippocampal dentate gyrus (DG), a region of neurogenesis in adulthood, using immunofluorescence. In the adult DG, cyclin E-immunoreactive (cyclin E+) cells was limited to postmitotic cells. In the subgranular zone, cyclin E was detected in the vertical process of radial glia-like cells, which were marked by the neural stem cell markers nestin and GFAP. Cyclin E was also detected in the nucleus of cells, which were labeled with stage-specific neuronal cell markers, including Pax6, Sox2, NeuroD, doublecortin, and NeuN. The densities of cyclin E+ cells in the DG reduced and increased with age and running, respectively. Furthermore, the majority of cyclin E+ cells co-expressed active caspase-3, a marker of apoptosis. Together, the results indicate that cyclin E is expressed in the process of quiescent neural stem cells and in the nucleus of active caspase-3+ cells during neuronal cell differentiation, suggesting that cyclin E has a Cdk-independent function, which might be important for the mechanisms regulating adult hippocampal neurogenesis.

  5. Genetic inactivation of Cdk7 leads to cell cycle arrest and induces premature aging due to adult stem cell exhaustion

    PubMed Central

    Ganuza, Miguel; Sáiz-Ladera, Cristina; Cañamero, Marta; Gómez, Gonzalo; Schneider, Ralph; Blasco, María A; Pisano, David; Paramio, Jesús M; Santamaría, David; Barbacid, Mariano

    2012-01-01

    Cyclin-dependent kinase (Cdk)7, the catalytic subunit of the Cdk-activating kinase (CAK) complex has been implicated in the control of cell cycle progression and of RNA polymerase II (RNA pol II)-mediated transcription. Genetic inactivation of the Cdk7 locus revealed that whereas Cdk7 is completely dispensable for global transcription, is essential for the cell cycle via phosphorylation of Cdk1 and Cdk2. In vivo, Cdk7 is also indispensable for cell proliferation except during the initial stages of embryonic development. Interestingly, widespread elimination of Cdk7 in adult tissues with low proliferative indexes had no phenotypic consequences. However, ablation of conditional Cdk7 alleles in tissues with elevated cellular turnover led to the efficient repopulation of these tissues with Cdk7-expressing cells most likely derived from adult stem cells that may have escaped the inactivation of their targeted Cdk7 alleles. This process, a physiological attempt to maintain tissue homeostasis, led to the attrition of adult stem cell pools and to the appearance of age-related phenotypes, including telomere shortening and early death. PMID:22505032

  6. Expression of polysialylated neural cell adhesion molecules on adult stem cells after neuronal differentiation of inner ear spiral ganglion neurons.

    PubMed

    Park, Kyoung Ho; Yeo, Sang Won; Troy, Frederic A

    2014-10-17

    During brain development, polysialylated (polySia) neural cell adhesion molecules (polySia-NCAMs) modulate cell-cell adhesive interactions involved in synaptogenesis, neural plasticity, myelination, and neural stem cell (NSC) proliferation and differentiation. Our findings show that polySia-NCAM is expressed on NSC isolated from adult guinea pig spiral ganglion (GPSG), and in neurons and Schwann cells after differentiation of the NSC with epidermal, glia, fibroblast growth factors (GFs) and neurotrophins. These differentiated cells were immunoreactive with mAb's to polySia, NCAM, β-III tubulin, nestin, S-100 and stained with BrdU. NSC could regenerate and be differentiated into neurons and Schwann cells. We conclude: (1) polySia is expressed on NSC isolated from adult GPSG and on neurons and Schwann cells differentiated from these NSC; (2) polySia is expressed on neurons primarily during the early stage of neuronal development and is expressed on Schwann cells at points of cell-cell contact; (3) polySia is a functional biomarker that modulates neuronal differentiation in inner ear stem cells. These new findings suggest that replacement of defective cells in the inner ear of hearing impaired patients using adult spiral ganglion neurons may offer potential hope to improve the quality of life for patients with auditory dysfunction and impaired hearing disorders.

  7. Neural Stem Cells in the Adult Subventricular Zone Oxidize Fatty Acids to Produce Energy and Support Neurogenic Activity.

    PubMed

    Stoll, Elizabeth A; Makin, Rebecca; Sweet, Ian R; Trevelyan, Andrew J; Miwa, Satomi; Horner, Philip J; Turnbull, Douglass M

    2015-07-01

    Neural activity is tightly coupled to energy consumption, particularly sugars such as glucose. However, we find that, unlike mature neurons and astrocytes, neural stem/progenitor cells (NSPCs) do not require glucose to sustain aerobic respiration. NSPCs within the adult subventricular zone (SVZ) express enzymes required for fatty acid oxidation and show sustained increases in oxygen consumption upon treatment with a polyunsaturated fatty acid. NSPCs also demonstrate sustained decreases in oxygen consumption upon treatment with etomoxir, an inhibitor of fatty acid oxidation. In addition, etomoxir decreases the proliferation of SVZ NSPCs without affecting cellular survival. Finally, higher levels of neurogenesis can be achieved in aged mice by ectopically expressing proliferator-activated receptor gamma coactivator 1 alpha (PGC1α), a factor that increases cellular aerobic capacity by promoting mitochondrial biogenesis and metabolic gene transcription. Regulation of metabolic fuel availability could prove a powerful tool in promoting or limiting cellular proliferation in the central nervous system. Stem Cells 2015;33:2306-2319.

  8. Resveratrol rescues SIRT1-dependent adult stem cell decline and alleviates progeroid features in laminopathy-based progeria.

    PubMed

    Liu, Baohua; Ghosh, Shrestha; Yang, Xi; Zheng, Huiling; Liu, Xinguang; Wang, Zimei; Jin, Guoxiang; Zheng, Bojian; Kennedy, Brian K; Suh, Yousin; Kaeberlein, Matt; Tryggvason, Karl; Zhou, Zhongjun

    2012-12-05

    Abnormal splicing of LMNA gene or aberrant processing of prelamin A results in progeroid syndrome. Here we show that lamin A interacts with and activates SIRT1. SIRT1 exhibits reduced association with nuclear matrix (NM) and decreased deacetylase activity in the presence of progerin or prelamin A, leading to rapid depletion of adult stem cells (ASCs) in Zmpste24(-/-) mice. Resveratrol enhances the binding between SIRT1 and A-type lamins to increases its deacetylase activity. Resveratrol treatment rescues ASC decline, slows down body weight loss, improves trabecular bone structure and mineral density, and significantly extends the life span in Zmpste24(-/-) mice. Our data demonstrate lamin A as an activator of SIRT1 and provide a mechanistic explanation for the activation of SIRT1 by resveratrol. The link between conserved SIRT1 longevity pathway and progeria suggests a stem cell-based and SIRT1 pathway-dependent therapeutic strategy for progeria.

  9. The next generation of burns treatment: intelligent films and matrix, controlled enzymatic debridement, and adult stem cells.

    PubMed

    Drago, H; Marín, G H; Sturla, F; Roque, G; Mártire, K; Díaz Aquino, V; Lamonega, R; Gardiner, C; Ichim, T; Riordan, N; Raimondi, J C; Bossi, S; Samadikuchaksaraei, A; van Leeuwen, M; Tau, J M; Núñez, L; Larsen, G; Spretz, R; Mansilla, E

    2010-01-01

    We describe a novel technology based on nanoengineered multifunctional acellular biologic scaffolds combined with wound dressings and films of the same kind. This method allows selective delivery and release of shielded biomaterials and bioactive substances to a desired wound or damaged tissue while stimulating the selective anchoring and adhesion of endogenous circulating repairing cells, such as mesenchymal stem cells, to obtain a faster and more physiologic healing process. We also present a new controlled enzymatic debridement process for more effective burned tissue scarolysis. In light of our preliminary in vitro and in vivo data, we are convinced that these approaches can include the use of other kinds of adult stem cells, such as endometrial regenerative cells, to improve the vascularization of the constructs, with great potential in the entire tissue and organ regeneration field but especially for the treatment of severely burned patients, changing the way these lesions may be treated in the future.

  10. Paraganglioma-like dermal melanocytic tumor: a unique entity distinct from cellular blue nevus, clear cell sarcoma, and cutaneous melanoma.

    PubMed

    Deyrup, Andrea T; Althof, Pamela; Zhou, Ming; Morgan, Michael; Solomon, Alvin R; Bridge, Julia A; Weiss, Sharon W

    2004-12-01

    We are reporting a previously undescribed primary dermal melanocytic tumor identified by reviewing all dermal melanocytic tumors referred in consultation that did not qualify histologically as a previously described entity. From these cases, 8 were remarkably similar. We termed them "paraganglioma-like dermal melanocytic tumor" (PDMT) based on their nested growth pattern. This term is used descriptively and does not imply any histogenetic or biologic similarity to true paraganglioma. PDMT is primarily a tumor of the extremities of adult females (18-53 years, mean 35 years; males 2; females 6) which present as a dermal nodule (range, 0.5-4.2 cm; mean, 1.4 cm) composed of nests of clear to amphophilic oval cells separated by delicate fibrous strands. Nuclear atypia was mild and mitotic activity low (1-4 mitoses/10 HPF). Melanin was not obvious on light microscopy. Tumors expressed S-100 protein (8 of 8), Melan-A (4 of 8), HMB-45 (8 of 8), and microphthalmia transcription factor (8 of 8) and lacked pancytokeratin (8 of 8) and smooth muscle actin (8 of 8). FISH analysis of 5 cases revealed an intact EWS gene locus, supporting absence of the clear cell sarcoma 12;22 translocation. Follow-up information in 8 patients (range, 35-92 months; mean, 54 months) indicated that all were alive without disease. PDMT comprises a clinically and pathologically unique subtype of dermal melanocytic tumors. Our study suggests a benign course, although a lesion of low malignant potential cannot be excluded.

  11. Positive and negative elements regulate a melanocyte-specific promoter.

    PubMed Central

    Lowings, P; Yavuzer, U; Goding, C R

    1992-01-01

    Melanocytes are specialized cells residing in the hair follicles, the eye, and the basal layer of the human epidermis whose primary function is the production of the pigment melanin, giving rise to skin, hair, and eye color. Melanogenesis, a process unique to melanocytes that involves the processing of tyrosine by a number of melanocyte-specific enzymes, including tyrosinase and tyrosinase-related protein 1 (TRP-1), occurs only after differentiation from the melanocyte precursor, the melanoblast. In humans, melanogenesis is inducible by UV irradiation, with melanin being transferred from the melanocyte in the epidermis to the surrounding keratinocytes as protection from UV-induced damage. Excessive exposure to UV, however, is the primary cause of malignant melanoma, an increasingly common and highly aggressive disease. As an initial approach to understanding the regulation of melanocyte differentiation and melanocyte-specific transcription, we have isolated the gene encoding TRP-1 and examined the cis- and trans-acting factors required for cell-type-specific expression. We find that the TRP-1 promoter comprises both positive and negative regulatory elements which confer efficient expression in a TRP-1-expressing, pigmented melanoma cell line but not in NIH 3T3 or JEG3 cells and that a minimal promoter extending between -44 and +107 is sufficient for cell-type-specific expression. Assays for DNA-protein interactions coupled with extensive mutagenesis identified three factors, whose binding correlated with the function of two positive and one negative regulatory element. One of these factors, termed M-box-binding factor 1, binds to an 11-bp motif, the M box, which acts as a positive regulatory element both in TRP-1-expressing and -nonexpressing cell lines, despite being entirely conserved between the melanocyte-specific tyrosinase and TRP-1 promoters. The possible mechanisms underlying melanocyte-specific gene expression are discussed. Images PMID:1321344

  12. Adult stem cell as new advanced therapy for experimental neuropathic pain treatment.

    PubMed

    Franchi, Silvia; Castelli, Mara; Amodeo, Giada; Niada, Stefania; Ferrari, Daniela; Vescovi, Angelo; Brini, Anna Teresa; Panerai, Alberto Emilio; Sacerdote, Paola

    2014-01-01

    Neuropathic pain (NP) is a highly invalidating disease resulting as consequence of a lesion or disease affecting the somatosensory system. All the pharmacological treatments today in use give a long lasting pain relief only in a limited percentage of patients before pain reappears making NP an incurable disease. New approaches are therefore needed and research is testing stem cell usage. Several papers have been written on experimental neuropathic pain treatment using stem cells of different origin and species to treat experimental NP. The original idea was based on the capacity of stem cell to offer a totipotent cellular source for replacing injured neural cells and for delivering trophic factors to lesion site; soon the researchers agreed that the capacity of stem cells to contrast NP was not dependent upon their regenerative effect but was mostly linked to a bidirectional interaction between the stem cell and damaged microenvironment resident cells. In this paper we review the preclinical studies produced in the last years assessing the effects induced by several stem cells in different models of neuropathic pain. The overall positive results obtained on pain remission by using stem cells that are safe, of easy isolation, and which may allow an autologous transplant in patients may be encouraging for moving from bench to bedside, although there are several issues that still need to be solved.

  13. Allogeneic Hematopoietic Stem Cell Transplantation for Adult Acute Lymphoblastic Leukemia: Results from a Single Center, 1993-2011

    PubMed Central

    Yonal-Hindilerden, Ipek; Kalayoglu-Besisik, Sevgi; Gurses-Koc, Nuray; Hindilerden, Fehmi; Sargin, Deniz

    2017-01-01

    Background: For adult ALL patients, the indications and appropriate timing of allogeneic hematopoietic stem cell transplantation (AHSCT) continue to be debated. The primary aim of this single-institution study was to compare the results of our adult ALL patients that had been allografted with those reported in the current literature. Subjects and Methods: This study included 53 consecutive adults with acute lymphoblastic leukemia (ALL) who underwent allogeneic hematopoietic stem cell transplantation (AHSCT) with myeloablative (92%) and reduced-intensity (8%) conditioning between 1993 and 2011. Results: Mean patient age was 27 years (SD:8.62) and donor age was 33.7 years (SD:9.47). Fourteen patients were in first remission; 21 in ≥2nd remission, 15 in relapse and 3 had primary refractory leukemia. Thirty-four, 15 and 4 patients received busulfan plus cyclophosphamide, cyclophosphamide/total body irradiation and fludarabine-based regimens, respectively. For graft-versus-host disease (GVHD) prophylaxis, cyclosporine plus methotrexate were used. Forty-six donors were related and 7 were unrelated. Thirty patients received granulocyte-colony stimulating factor (G-CSF) mobilized peripheral blood and 23 received bone marrow as stem cell source. Twenty-six patients relapsed at a mean duration of 11.3 months (SD:19.1). Forty-four patients succumbed to their disease after a mean follow-up of 13.6 months (SD:19.5). The cause of mortality was relapse (n=24; 54.5%) and transplant-related etiologies (n=20; 45.5%). The estimated five year probabilities of overall survival (OS) and progression-free survival (PFS) were 37% and 12%, respectively. Conclusion: By multivariate analyses, transplantation in first remission was the most important predictor of transplant success. PMID:28286617

  14. Giant melanocytic nevi with neurocutaneous melanosis masquerading as neurofibromas

    PubMed Central

    Gowda, Vykuntaraju K.; Basude, Anita; Srinivas, Sahana M.; Bhat, Maya

    2016-01-01

    Neurocutaneous melanosis is congenital melanocytic nevus with neurological manifestations. We report a 4-year-old female child presenting with hyperpigmented and nodular skin lesion associated with developmental delay and convulsions. The child had multiple brownish-black nevi on the face and chest and giant melanocytic nevi on thoraco-abdomen, back, and gluteal region. Computed tomography scan of the brain showed calcification in the pons, right cerebellar hemisphere, and left medial temporal lobe. Skin biopsy done from nodular hyperpigmented site was suggestive of melanocytic nevi. Electroencephalogram showed multifocal epileptiform discharges. PMID:27857802

  15. Multiple roles of NF1 in the melanocyte lineage.

    PubMed

    Larribère, Lionel; Utikal, Jochen

    2016-07-01

    NF1 is a tumour suppressor gene, germline mutations of which lead to neurofibromatosis type 1 syndrome. Patients develop benign tumours from several types of cells including neural crest-derived cells. NF1 somatic mutations also occur in 15% of sporadic melanoma, a cancer originating from melanocytes. Evidence now suggests the involvement of NF1 mutations in melanoma resistance to targeted therapies. Although NF1 is ubiquitously expressed, genetic links between NF1 and genes involved in melanocyte biology have been described, implying the lineage-specific mechanisms. In this review, we summarize and discuss the latest advances related to the roles of NF1 in melanocyte biology and in cutaneous melanoma.

  16. Poised Regeneration of Zebrafish Melanocytes Involves Direct Differentiation and Concurrent Replenishment of Tissue-Resident Progenitor Cells.

    PubMed

    Iyengar, Sharanya; Kasheta, Melissa; Ceol, Craig J

    2015-06-22

    Efficient regeneration following injury is critical for maintaining tissue function and enabling organismal survival. Cells reconstituting damaged tissue are often generated from resident stem or progenitor cells or from cells that have dedifferentiated and become proliferative. While lineage-tracing studies have defined cellular sources of regeneration in many tissues, the process by which these cells execute the regenerative process is largely obscure. Here, we have identified tissue-resident progenitor cells that mediate regeneration of zebrafish stripe melanocytes and defined how these cells reconstitute pigmentation. Nearly all regeneration melanocytes arise through direct differentiation of progenitor cells. Wnt signaling is activated prior to differentiation, and inhibition of Wnt signaling impairs regeneration. Additional progenitors divide symmetrically to sustain the pool of progenitor cells. Combining direct differentiation with symmetric progenitor divisions may serve as a means to rapidly repair injured tissue while preserving the capacity to regenerate.

  17. Direct Activation of Amidohydrolase Domain-Containing 1 Gene by Thyroid Hormone Implicates a Role in the Formation of Adult Intestinal Stem Cells During Xenopus Metamorphosis.

    PubMed

    Okada, Morihiro; Miller, Thomas C; Fu, Liezhen; Shi, Yun-Bo

    2015-09-01

    The T3-dependent anuran metamorphosis resembles postembryonic development in mammals, the period around birth when plasma T3 levels peak. In particular, the remodeling of the intestine during metamorphosis mimics neonatal intestinal maturation in mammals when the adult intestinal epithelial self-renewing system is established. We have been using intestinal metamorphosis to investigate how the organ-specific adult stem cells are formed during vertebrate development. Early studies in Xenopus laevis have shown that this process involves complete degeneration of the larval epithelium and de novo formation of adult stem cells. A tissue-specific microarray analysis of intestinal gene expression during Xenopus laevis metamorphosis has identified a number of candidate stem cell genes. Here we have carried out detailed analyses of one such gene, amidohydrolase domain containing 1 (AMDHD1) gene, which encodes an enzyme in the histidine catabolic pathway. We show that AMDHD1 is exclusively expressed in the proliferating adult epithelial stem cells during metamorphosis with little expression in other intestinal tissues. We further provide evidence that T3 activates AMDHD1 gene expression directly at the transcription level through T3 receptor binding to the AMDHD1 gene in the intestine. In addition, we have reported earlier that histidine ammonia-lyase gene, another gene in histidine catabolic pathway, is similarly regulated by T3 in the intestine. These results together suggest that histidine catabolism plays a critical role in the formation and/or proliferation of adult intestinal stem cells during metamorphosis.

  18. [Stem cells in adult retina--current state of research, future therapeutic prospects].

    PubMed

    Machalińska, Anna; Zuba-Surma, Ewa K

    2009-01-01

    The latest research reports revealed the presence of stem/progenitor cells located in different regions of matured eye. They are able to differentiate into retinal pigment epithelium cells as well as neural structure of retina. These cells were identified in neurosensory retina, pigment epithelium and within cilliary body and iris epithelium. Moreover, it has been proved that Muller glia possess the potential of differentiation into retinal cells. These findings indicate the presence of potential mechanisms enabling retinal cell repopulation and retinal tissue regeneration. In the present work, the recent reports documenting the presence of different stem cell populations in eye have been reviewed, particularly focusing on recently identified very small embryonic-like stem cells (VSEL-SCs). The potential clinical applications of the residing stem cells and limitations of such therapeutic strategies have been also discussed.

  19. Adult spinal cord ependymal layer: a promising pool of quiescent stem cells to treat spinal cord injury.

    PubMed

    Panayiotou, Elena; Malas, Stavros

    2013-11-28

    Spinal cord injury (SCI) is a major health burden and currently there is no effective medical intervention. Research performed over the last decade revealed that cells surrounding the central canal of the adult spinal cord and forming the ependymal layer acquire stem cell properties either in vitro or in response to injury. Following SCI activated ependymal cells generate progeny cells which migrate to the injury site but fail to produce the appropriate type of cells in sufficient number to limit the damage, rendering this physiological response mainly ineffective. Research is now focusing on the manipulation of ependymal cells to produce cells of the oligodendrocyte lineage which are primarily lost in such a situation leading to secondary neuronal degeneration. Thus, there is a need for a more focused approach to understand the molecular properties of adult ependymal cells in greater detail and develop effective strategies for guiding their response during SCI.

  20. Regulation of haematopoietic stem cell proliferation by stimulatory factors produced by murine fetal and adult liver.

    PubMed Central

    Dawood, K A; Briscoe, C V; Thomas, D B; Riches, A C

    1990-01-01

    Haematopoietic stem cells in murine fetal liver are in a proliferative state unlike those in normal bone marrow which are quiescent. A regulatory activity is produced by cells in the fetal liver which will switch quiescent normal bone marrow haematopoietic stem cells into cell cycle in vitro. This regulator from Day 15 fetal liver cells is produced by adherent cells and by cells fractionated on a Percoll gradient in the 1.064 and 1.076 g per cm3 density bands but not in the 1.123 g per cm3 band. Colony-stimulating factor cannot be detected in the supernatants containing the stem cell regulatory activity. The stimulator can be detected in supernatants produced from cell suspensions of liver cells at Day 15 and Day 17 of gestation and 24 hours and 72 hours after birth. However by 1 week after birth the production of the stimulator decreases and is undetectable 3 and 10 weeks after birth. The total numbers of haematopoietic stem cells (CFU-S) in fetal liver decrease from Day 15 of gestation and only small numbers are present 1 week after birth. Thus the decline in the production of haematopoietic stem cell proliferation stimulator correlates with the decrease in haematopoietic stem cell numbers in the liver through gestation and after birth. PMID:2323992

  1. Radioimmunoassay for. gamma. -melanocyte stimulating hormone

    SciTech Connect

    Shibasaki, T.; Ling, N.; Guillemin, R.

    1980-05-26

    A specific radioimmunoassay for ..gamma..-melanocyte stimulating hormone-like peptides was developed. An antiserum raised in rabbit to synthetic bovine ..gamma../sub 3/-MSH, one of the possible ..gamma..-MSH peptides, specifically recognizes the portion between His/sup 5/ and Arg/sup 14/ of ..gamma../sub 3/-MSH without significant cross-reaction with other synthetic ..gamma..-MSH-like peptides, ..cap alpha..-, ..beta..-MSH, adrenocorticotropin, and ..beta..-endorphin. The usable range of this RIA is 10 pg to 600 pg of synthetic ..gamma../sub 3/-MSH. Three immunoreactive ..gamma..-MSH peaks were thus found in gel permeation chromatography of the whole bovine pituitary extract.

  2. Congenital melanocytic nevus: two clinicopathological forms.

    PubMed

    Magaña, Mario; Sánchez-Romero, Elizabeth; Magaña, Pablo; Beck-Magaña, Andrés; Magaña-Lozano, Mario

    2015-01-01

    Congenital melanocytic nevus (CMN) is a hamartomatous disease for which many attempts at classification have been proposed. This disease is relevant not only because of its functional and esthetic implications but also because it is a well-documented precursor to malignant melanoma. We performed a clinical and pathological prospective study of 200 cases of CMN and were able to identify 2 different forms of CMN, each one with biological, clinical, and histopathological features and criteria that are consistent and repeatable. We propose to name them types I and II. Type I CMN is the most common, usually, if not always, a single lesion, it consists of a plaque that involves only 1 anatomic region and does not go beyond it; type I CNM grows in proportion to the growth of the child, melanoma rarely develops from it, and when it does it usually arises at the dermoepidermal junction. Its histopathology shows cords, strands, nests, and single units of melanocytes spreading between collagen bundles only in the dermis and frequently the epidermis too, but without trespassing to the hypodermis, that is, it is superficial. Type II CMN is always made up of many lesions, one of them being very large and surrounded by many lesions; histopathologically, it involves not only the skin but also deeper structures, sometimes bone and central nervous system; therefore, it is deep; when melanoma develops, it does in the dermal component and usually from the largest plaque. This type of CMN is the one that develops neurocutaneous melanocytosis. This system is not only easy and logical but it also has biologic advantages and the clinical-pathological correlation and criteria are repeatable by clinicians and pathologists.

  3. I.V. infusion of brain-derived neurotrophic factor gene-modified human mesenchymal stem cells protects against injury in a cerebral ischemia model in adult rat.

    PubMed

    Nomura, T; Honmou, O; Harada, K; Houkin, K; Hamada, H; Kocsis, J D

    2005-01-01

    I.V. delivery of mesenchymal stem cells prepared from adult bone marrow reduces infarction size and ameliorates functional deficits in rat cerebral ischemia models. Administration of the brain-derived neurotrophic factor to the infarction site has also been demonstrated to be neuroprotective. To test the hypothesis that brain-derived neurotrophic factor contributes to the therapeutic benefits of mesenchymal stem cell delivery, we compared the efficacy of systemic delivery of human mesenchymal stem cells and human mesenchymal stem cells transfected with a fiber-mutant F/RGD adenovirus vector with a brain-derived neurotrophic factor gene (brain-derived neurotrophic factor-human mesenchymal stem cells). A permanent middle cerebral artery occlusion was induced by intraluminal vascular occlusion with a microfilament. Human mesenchymal stem cells and brain-derived neurotrophic factor-human mesenchymal stem cells were i.v. injected into the rats 6 h after middle cerebral artery occlusion. Lesion size was assessed at 6 h, 1, 3 and 7 days using MR imaging, and histological methods. Functional outcome was assessed using the treadmill stress test. Both human mesenchymal stem cells and brain-derived neurotrophic factor-human mesenchymal stem cells reduced lesion volume and elicited functional improvement compared with the control sham group, but the effect was greater in the brain-derived neurotrophic factor-human mesenchymal stem cell group. ELISA analysis of the infarcted hemisphere revealed an increase in brain-derived neurotrophic factor in the human mesenchymal stem cell groups, but a greater increase in the brain-derived neurotrophic factor-human mesenchymal stem cell group. These data support the hypothesis that brain-derived neurotrophic factor contributes to neuroprotection in cerebral ischemia and cellular delivery of brain-derived neurotrophic factor can be achieved by i.v. delivery of human mesenchymal stem cells.

  4. Monitoring human melanocytic cell responses to piperine using multispectral imaging

    NASA Astrophysics Data System (ADS)

    Samatham, Ravikant; Phillips, Kevin G.; Sonka, Julia; Yelma, Aznegashe; Reddy, Neha; Vanka, Meenakshi; Thuillier, Philippe; Soumyanath, Amala; Jacques, Steven

    2011-03-01

    Vitiligo is a depigmentary disease characterized by melanocyte loss attributed most commonly to autoimmune mechanisms. Currently vitiligo has a high incidence (1% worldwide) but a poor set of treatment options. Piperine, a compound found in black pepper, is a potential treatment for the depigmentary skin disease vitiligo, due to its ability to stimulate mouse epidermal melanocyte proliferation in vitro and in vivo. The present study investigates the use of multispectral imaging and an image processing technique based on local contrast to quantify the stimulatory effects of piperine on human melanocyte proliferation in reconstructed epidermis. We demonstrate the ability of the imaging method to quantify increased pigmentation in response to piperine treatment. The quantization of melanocyte stimulation by the proposed imaging technique illustrates the potential use of this technology to quickly assess therapeutic responses of vitiligo tissue culture models to treatment non-invasively.

  5. SRY-box-containing Gene 2 Regulation of Nuclear Receptor Tailless (Tlx) Transcription in Adult Neural Stem Cells*

    PubMed Central

    Shimozaki, Koji; Zhang, Chun-Li; Suh, Hoonkyo; Denli, Ahmet M.; Evans, Ronald M.; Gage, Fred H.

    2012-01-01

    Adult neurogenesis is maintained by self-renewable neural stem cells (NSCs). Their activity is regulated by multiple signaling pathways and key transcription factors. However, it has been unclear whether these factors interplay with each other at the molecular level. Here we show that SRY-box-containing gene 2 (Sox2) and nuclear receptor tailless (TLX) form a molecular network in adult NSCs. We observed that both Sox2 and TLX proteins bind to the upstream region of Tlx gene. Sox2 positively regulates Tlx expression, whereas the binding of TLX to its own promoter suppresses its transcriptional activity in luciferase reporter assays. Such TLX-mediated suppression can be antagonized by overexpressing wild-type Sox2 but not a mutant lacking the transcriptional activation domain. Furthermore, through regions involved in DNA-binding activity, Sox2 and TLX physically interact to form a complex on DNAs that contain a consensus binding site for TLX. Finally, depletion of Sox2 revealed the potential negative feedback loop of TLX expression that is antagonized by Sox2 in adult NSCs. These data suggest that Sox2 plays an important role in Tlx transcription in cultured adult NSCs. PMID:22194602

  6. Hindsight/RREB-1 functions in both the specification and differentiation of stem cells in the adult midgut of Drosophila

    PubMed Central

    Baechler, Brittany L.; McKnight, Cameron; Pruchnicki, Porsha C.; Biro, Nicole A.; Reed, Bruce H.

    2016-01-01

    ABSTRACT The adult Drosophila midgut is established during the larval/pupal transition from undifferentiated cells known as adult midgut precursors (AMPs). Four fundamental cell types are found in the adult midgut epithelium: undifferentiated intestinal stem cells (ISCs) and their committed daughter cells, enteroblasts (EBs), plus enterocytes (ECs) and enteroendocrine cells (EEs). Using the Drosophila posterior midgut as a model, we have studied the function of the transcription factor Hindsight (Hnt)/RREB-1 and its relationship to the Notch and Egfr signaling pathways. We show that hnt is required for EC differentiation in the context of ISC-to-EC differentiation, but not in the context of AMP-to-EC differentiation. In addition, we show that hnt is required for the establishment of viable or functional ISCs. Overall, our studies introduce hnt as a key factor in the regulation of both the developing and the mature adult midgut. We suggest that the nature of these contextual differences can be explained through the interaction of hnt with multiple signaling pathways. PMID:26658272

  7. Outcome of allogeneic hematopoietic stem cell transplantation in adult patients with acute myeloid leukemia harboring trisomy 8.

    PubMed

    Konuma, Takaaki; Kondo, Tadakazu; Yamashita, Takuya; Uchida, Naoyuki; Fukuda, Takahiro; Ozawa, Yukiyasu; Ohashi, Kazuteru; Ogawa, Hiroyasu; Kato, Chiaki; Takahashi, Satoshi; Kanamori, Heiwa; Eto, Tetsuya; Nakaseko, Chiaki; Kohno, Akio; Ichinohe, Tatsuo; Atsuta, Yoshiko; Takami, Akiyoshi; Yano, Shingo

    2017-03-01

    Trisomy 8 (+8) is one of the most common cytogenetic abnormalities in adult patients with acute myeloid leukemia (AML). However, the outcome of allogeneic hematopoietic stem cell transplantation (HSCT) in adult patients with AML harboring +8 remains unclear. To evaluate, the outcome and prognostic factors in patients with AML harboring +8 as the only chromosomal abnormality or in association with other abnormalities, we retrospectively analyzed the Japanese registration data of 631 adult patients with AML harboring +8 treated with allogeneic HSCT between 1990 and 2013. In total, 388 (61%) patients were not in remission at the time of HSCT. With a median follow-up of 38.5 months, the probability of overall survival and the cumulative incidence of relapse at 3 years were 40 and 34%, respectively. In the multivariate analysis, two or more additional cytogenetic abnormalities and not being in remission at the time of HSCT were significantly associated with a higher overall mortality and relapse. Nevertheless, no significant impact on the outcome was observed in cases with one cytogenetic abnormality in addition to +8. Although more than 60% of the patients received HSCT when not in remission, allogeneic HSCT offered a curative option for adult patients with AML harboring +8.

  8. Planarian yorkie/YAP functions to integrate adult stem cell proliferation, organ homeostasis and maintenance of axial patterning.

    PubMed

    Lin, Alexander Y T; Pearson, Bret J

    2014-03-01

    During adult homeostasis and regeneration, the freshwater planarian must accomplish a constant balance between cell proliferation and cell death, while also maintaining proper tissue and organ size and patterning. How these ordered processes are precisely modulated remains relatively unknown. Here we show that planarians use the downstream effector of the Hippo signaling cascade, yorkie (yki; YAP in vertebrates) to control a diverse set of pleiotropic processes in organ homeostasis, stem cell regulation, regeneration and axial patterning. We show that yki functions to maintain the homeostasis of the planarian excretory (protonephridial) system and to limit stem cell proliferation, but does not affect the differentiation process or cell death. Finally, we show that Yki acts synergistically with WNT/β-catenin signaling to repress head determination by limiting the expression domains of posterior WNT genes and that of the WNT-inhibitor notum. Together, our data show that yki is a key gene in planarians that integrates stem cell proliferation control, organ homeostasis, and the spatial patterning of tissues.

  9. Induced neural stem cells achieve long-term survival and functional integration in the adult mouse brain.

    PubMed

    Hemmer, Kathrin; Zhang, Mingyue; van Wüllen, Thea; Sakalem, Marna; Tapia, Natalia; Baumuratov, Aidos; Kaltschmidt, Christian; Kaltschmidt, Barbara; Schöler, Hans R; Zhang, Weiqi; Schwamborn, Jens C

    2014-09-09

    Differentiated cells can be converted directly into multipotent neural stem cells (i.e., induced neural stem cells [iNSCs]). iNSCs offer an attractive alternative to induced pluripotent stem cell (iPSC) technology with regard to regenerative therapies. Here, we show an in vivo long-term analysis of transplanted iNSCs in the adult mouse brain. iNSCs showed sound in vivo long-term survival rates without graft overgrowths. The cells displayed a neural multilineage potential with a clear bias toward astrocytes and a permanent downregulation of progenitor and cell-cycle markers, indicating that iNSCs are not predisposed to tumor formation. Furthermore, the formation of synaptic connections as well as neuronal and glial electrophysiological properties demonstrated that differentiated iNSCs migrated, functionally integrated, and interacted with the existing neuronal circuitry. We conclude that iNSC long-term transplantation is a safe procedure; moreover, it might represent an interesting tool for future personalized regenerative applications.

  10. Mediation of Autophagic Cell Death by Type 3 Ryanodine Receptor (RyR3) in Adult Hippocampal Neural Stem Cells

    PubMed Central

    Chung, Kyung Min; Jeong, Eun-Ji; Park, Hyunhee; An, Hyun-Kyu; Yu, Seong-Woon

    2016-01-01

    Cytoplasmic Ca2+ actively engages in diverse intracellular processes from protein synthesis, folding and trafficking to cell survival and death. Dysregulation of intracellular Ca2+ levels is observed in various neuropathological states including Alzheimer’s and Parkinson’s diseases. Ryanodine receptors (RyRs) and inositol 1,4,5-triphosphate receptors (IP3Rs), the main Ca2+ release channels located in endoplasmic reticulum (ER) membranes, are known to direct various cellular events such as autophagy and apoptosis. Here we investigated the intracellular Ca2+-mediated regulation of survival and death of adult hippocampal neural stem (HCN) cells utilizing an insulin withdrawal model of autophagic cell death (ACD). Despite comparable expression levels of RyR and IP3R transcripts in HCN cells at normal state, the expression levels of RyRs—especially RyR3—were markedly upregulated upon insulin withdrawal. While treatment with the RyR agonist caffeine significantly promoted the autophagic death of insulin-deficient HCN cells, treatment with its inhibitor dantrolene prevented the induction of autophagy following insulin withdrawal. Furthermore, CRISPR/Cas9-mediated knockout of the RyR3 gene abolished ACD of HCN cells. This study delineates a distinct, RyR3-mediated ER Ca2+ regulation of autophagy and programmed cell death in neural stem cells. Our findings provide novel insights into the critical, yet understudied mechanisms underlying the regulatory function of ER Ca2+ in neural stem cell biology. PMID:27199668

  11. Enhanced genetic modification of adult growth factor mobilized peripheral blood hematopoietic stem and progenitor cells with rapamycin.

    PubMed

    Li, Lijing; Torres-Coronado, Mónica; Gu, Angel; Rao, Anitha; Gardner, Agnes M; Epps, Elizabeth W; Gonzalez, Nancy; Tran, Chy-Anh; Wu, Xiwei; Wang, Jin-Hui; DiGiusto, David L

    2014-10-01

    Genetic modification of adult human hematopoietic stem and progenitor cells (HSPCs) with lentiviral vectors leads to long-term gene expression in the progeny of the HSPCs and has been used to successfully treat several monogenic diseases. In some cases, the gene-modified cells have a selective growth advantage over nonmodified cells and eventually are the dominant engrafted population. However, in disease indications for which the gene-modified cells do not have a selective advantage, optimizing transduction of HSPC is paramount to successful stem cell-based gene therapy. We demonstrate here that transduction of adult CD34+ HSPCs with lentiviral vectors in the presence of rapamycin, a widely used mTORC1 inhibitor, results in an approximately threefold increase in stable gene marking with minimal effects on HSPC growth and differentiation. Using this approach, we have demonstrated that we can enhance the frequency of gene-modified HSPCs that give rise to clonogenic progeny in vitro without excessive increases in the number of vector copies per cell or changes in integration pattern. The genetic marking of HSPCs and expression of transgenes is durable, and transplantation of gene-modified HSPCs into immunodeficient mice results in high levels of gene marking of the lymphoid and myeloid progeny in vivo. The prior safe clinical history of rapamycin in other applications supports the use of this compound to generate gene-modified autologous HSPCs for our HIV gene therapy clinical trials.

  12. Human Adult Stem Cells Maintain a Constant Phenotype Profile Irrespective of Their Origin, Basal Media, and Long Term Cultures

    PubMed Central

    Somasundaram, Indumathi; Mishra, Rashmi; Radhakrishnan, Harikrishnan; Sankaran, Rajkumar; Garikipati, Venkata Naga Srikanth

    2015-01-01

    The study aims to identify the phenotypic marker expressions of different human adult stem cells derived from, namely, bone marrow, subcutaneous fat, and omentum fat, cultured in different media, namely, DMEM-Low Glucose, Alpha-MEM, DMEM-F12 and DMEM-KO and under long term culture conditions (>P20). We characterized immunophenotype by using various hematopoietic, mesenchymal, endothelial markers, and cell adhesion molecules in the long term cultures (Passages-P1, P3, P5, P9, P12, P15, and P20.) Interestingly, data revealed similar marker expression profiles irrespective of source, basal media, and extensive culturing. This demonstrates that all adult stem cell sources mentioned in this study share similar phenotypic marker and all media seem appropriate for culturing these sources. However, a disparity was observed in the markers such as CD49d, CD54, CD117, CD29, and CD106, thereby warranting further research on these markers. Besides the aforesaid objective, it is understood from the study that immunophenotyping acts as a valuable tool to identify inherent property of each cell, thereby leading to a valuable cell based therapy. PMID:25688272

  13. Immunohistochemical diagnosis of canine oral amelanotic melanocytic neoplasms.

    PubMed

    Smedley, R C; Lamoureux, J; Sledge, D G; Kiupel, M

    2011-01-01

    Definitive diagnosis of canine oral melanocytic neoplasms is often difficult because of variability in pigmentation and cellular pleomorphism. These neoplasms can resemble carcinomas, sarcomas, and round cell neoplasms, which differ in prognosis and treatment. A variety of immunohistochemical antibodies have been used for diagnosis of melanocytic neoplasms in humans and dogs; however, sensitivity and specificity of many markers have not been determined in amelanotic melanocytic neoplasms in dogs. The authors investigated a comprehensive panel of immunohistochemical markers in 49 canine oral amelanotic melanocytic neoplasms--namely, Melan-A, PNL2, HMB-45, microphthalmia transcription factor (MiTF), S-100, tyrosine hydroxylase, tyrosinase, tyrosinase-related proteins 1 and 2 (TRP-1 and TRP-2), and CD34. Ten well-differentiated cutaneous soft tissue spindle cell sarcomas were negative controls. Melan-A, PNL2, TRP-1, and TRP-2 were highly sensitive and 100% specific for the diagnosis of canine oral amelanotic melanocytic neoplasms. S-100 and MiTF showed high sensitivity but were less specific; that is, they also labeled a proportion of the soft tissue spindle cell sarcomas. HMB-45, tyrosinase, and tyrosine hydroxylase were 100% specific but had low sensitivities. CD34 did not label any of the melanocytic neoplasms but did label 80% of the soft tissue spindle cell sarcomas. A cost-effective and efficient immunodiagnostic cocktail containing antibodies against PNL2, Melan-A, TRP-1, and TRP-2 was created that had 100% specificity and 93.9% sensitivity in identifying canine oral amelanotic melanocytic neoplasms. The spindloid variant was the variant with the lowest sensitivity to the cocktail. The likelihood of correctly diagnosing canine oral amelanotic melanocytic neoplasms was dramatically higher when biopsy samples contained ample overlying and adjacent epithelium.

  14. Priming adult stem cells by hypoxic pretreatments for applications in regenerative medicine.

    PubMed

    Muscari, Claudio; Giordano, Emanuele; Bonafè, Francesca; Govoni, Marco; Pasini, Alice; Guarnieri, Carlo

    2013-08-29

    The efficiency of regenerative medicine can be ameliorated by improving the biological performances of stem cells before their transplantation. Several ex-vivo protocols of non-damaging cell hypoxia have been demonstrated to significantly increase survival, proliferation and post-engraftment differentiation potential of stem cells. The best results for priming cultured stem cells against a following, otherwise lethal, ischemic stress have been obtained with brief intermittent episodes of hypoxia, or anoxia, and reoxygenation in accordance with the extraordinary protection afforded by the conventional maneuver of ischemic preconditioning in severely ischemic organs. These protocols of hypoxic preconditioning can be rather easily reproduced in a laboratory; however, more suitable pharmacological interventions inducing stem cell responses similar to those activated in hypoxia are considered among the most promising solutions for future applications in cell therapy. Here we want to offer an up-to-date review of the molecular mechanisms translating hypoxia into beneficial events for regenerative medicine. To this aim the involvement of epigenetic modifications, microRNAs, and oxidative stress, mainly activated by hypoxia inducible factors, will be discussed. Stem cell adaptation to their natural hypoxic microenvironments (niche) in healthy and neoplastic tissues will be also considered.

  15. Distinctive molecular responses to ultraviolet radiation between keratinocytes and melanocytes

    PubMed Central

    Sun, Xiaoyun; Kim, Arianna; Nakatani, Masashi; Shen, Yao; Liu, Liang

    2017-01-01

    Solar ultraviolet radiation (UVR) is the major risk factor for skin carcinogenesis. To gain new insights into the molecular pathways mediating UVR effects in the skin, we performed comprehensive transcriptomic analyses to identify shared and distinctive molecular responses to UVR between human keratinocytes and melanocytes. Keratinocytes and melanocytes were irradiated with varying doses of UVB (10, 20 and 30 mJ/cm2) then analysed by RNA-Seq at different time points post-UVB radiation (4, 24 and 72 h). Under basal conditions, keratinocytes and melanocytes expressed similar number of genes, although they each expressed a distinctive subset of genes pertaining to their specific cellular identity. Upon UVB radiation, keratinocytes displayed a clear pattern of time- and dose-dependent changes in gene expression that was different from melanocytes. The early UVB-responsive gene set (4 h post-UVR) differed significantly from delayed UVB-responsive gene sets (24 and 72 h). We also identified multiple novel UVB signature genes including PRSS23, SERPINH1, LCE3D and CNFN, which were conserved between melanocyte and keratinocyte lines from different individuals. Taken together, our findings elucidated both common and distinctive molecular features between melanocytes and keratinocytes and uncovered novel UVB signature genes that might be utilized to predict UVB photobiological effects on the skin. PMID:27119462

  16. Congenital melanocytic nevus with features of hybrid schwannoma/perineurioma.

    PubMed

    Wang, Lei; Wang, Gang; Gao, Tianwen

    2013-05-01

    Neural differentiation by melanocytic nevi represents a well-recognized phenomenon, and melanocytic nevi with perineurial differentiation have been reported recently. We reported a case of a congenital melanocytic nevus with histopathologic features of hybrid schwannoma/perineurioma. The patient was a 36-year-old male who presented with a black tumor on his arm since birth. Histopathology showed a congenital melanocytic nevus in the superficial dermis, but more strikingly, in continuity with the melanocytic nevus, there was a well-circumscribed but unencapsulated nodule in the deep dermis. The nodule was composed of cellular and myxoid areas with storiform, laminated or whorled growth patterns. The cellular area was mainly composed of proliferation of plump spindle, oval or epithelioid cells. The myxoid area was mainly composed of proliferation of slender spindle cells with mucin deposition. Immunohistochemical stains showed that the cellular area was positive for S100 and CD34, weakly positive for EMA, negative for Glut-1 and collagen IV, the myxoid area was positive for S100, negative for CD34, strongly positive for EMA and focally positive for Glut-1 and collagen IV. Our results show that congenital melanocytic nevi may show neural differentiation with histopathologic features of hybrid schwannoma/perineurioma.

  17. Adult Stem Cells from the Hyaluronic Acid-Rich Node and Duct System Differentiate into Neuronal Cells and Repair Brain Injury

    PubMed Central

    Lee, Seung J.; Park, Sang H.; Kim, Yu I.; Hwang, Sunhee; Kwon, Patrick M.; Han, In S.

    2014-01-01

    The existence of a hyaluronic acid-rich node and duct system (HAR-NDS) within the lymphatic and blood vessels was demonstrated previously. The HAR-NDS was enriched with small (3.0–5.0 μm in diameter), adult stem cells with properties similar to those of the very small embryonic-like stem cells (VSELs). Sca-1+Lin−CD45− cells were enriched approximately 100-fold in the intravascular HAR-NDS compared with the bone marrow. We named these adult stem cells “node and duct stem cells (NDSCs).” NDSCs formed colonies on C2C12 feeder layers, were positive for fetal alkaline phosphatase, and could be subcultured on the feeder layers. NDSCs were Oct4+Nanog+SSEA-1+Sox2+, while VSELs were Oct4+Nanog+SSEA-1+Sox2−. NDSCs had higher sphere-forming efficiency and proliferative potential than VSELs, and they were found to differentiate into neuronal cells in vitro. Injection of NDSCs into mice partially repaired ischemic brain damage. Thus, we report the discovery of potential adult stem cells that may be involved in tissue regeneration. The intravascular HAR-NDS may serve as a route that delivers these stem cells to their target tissues. PMID:25027245

  18. CD45/CD11b Positive Subsets of Adult Lung Anchorage-Independent Cells Harness Epithelial Stem Cells

    PubMed Central

    Peter, Yakov; Sen, Namita; Levantini, Elena; Keller, Steven; Ingenito, Edward P; Ciner, Aaron; Sackstein, Robert; Shapiro, Steven D

    2015-01-01

    Compensatory growth is mediated by multiple cell types that interact during organ repair. To elucidate the relationship between the stem/progenitor cells that proliferate or differentiate and the somatic cells of lung, we utilized a novel ex vivo pneumoexplant system. Applying this technique, we identified a sustained culture of repopulating adult progenitors in the form of free floating anchorage-independent cells (AICs). AICs did not express integrin proteins α5, β3, and β7, and constituted 37% of the total culture at day 14, yielding a mixed yet conserved population that recapitulated RNA expression patterns of the healthy lung. AICs exhibited rapid proliferation manifested by a marked 60-fold increase in cell numbers by day 21. Over 50% of the AIC population was cKit+ or double-positive for CD45+ and CD11b+ antigenic determinants, consistent with cells of hematopoietic origin. The latter subset was found to be enriched with prosurfactant protein-C and SCGB1A1 expressing putative stem cells and with aquaporin-5 producing cells, characteristic of terminally differentiated alveolar epithelial type-1 pneumocytes. AICs undergo remodeling to form a cellular lining at the air/gel interface, and TGFβ1 treatment modifies protein expression, implying direct-differentiation of this population. These data confirm the active participation of clonogenic hematopietic stem cells in a mammalian model of lung repair and validate mixed stem/somatic cell cultures, which embrace sustained cell viability, proliferation, and differentiation, for use in studies of compensatory pulmonary growth. PMID:22585451

  19. Proton Beam Radiation Therapy in Treating Patients With Low Grade Gliomas

    ClinicalTrials.gov

    2015-12-14

    Adult Brain Tumor; Adult Brain Stem Glioma; Adult Diffuse Astrocytoma; Adult Ependymoma; Adult Grade II Meningioma; Adult Melanocytic Lesion; Adult Meningeal Hemangiopericytoma; Adult Mixed Glioma; Adult Oligodendroglioma; Adult Pineal Gland Astrocytoma; Adult Pineocytoma; Recurrent Adult Brain Tumor

  20. Nanostructural change of human melanocytes stimulated with α-melanocyte stimulating hormone observed by atomic force microscopy.

    PubMed

    Shin, Min Kyung; Lim, Hee Kyeong; Kang, Boo Kyoung; Lee, Gi-Ja; Uhm, Yun-Kyung; Lee, Mu-Hyoung

    2014-01-01

    It is well known that α-melanocyte stimulating hormone (α-MSH) induces melanization, but structural changes of melanocytes after α-MSH exposure are not well known. This study investigated the serial morphologic changes of human cultured melanocytes after stimulation with α-MSH using atomic force microscopy (AFM). Cultured human melanocytes were treated with α-MSH for 7 days. Contact mode AFM images were obtained using a NANOstation II and fixed melanocytes were scanned in PBS solution at a resolution of 512 × 512 pixels, at a scan speed of 0.4 line/s. The surface roughness and pore-like structures of the melanocytes were measured from topographic images using the Scanning Probe Imaging Processor. The surface roughness of cell body did not change significantly over time. All three roughness parameters (Sa, Sq, Sz) inside the pore-like structures on the dendrites increased significantly. The number of pore-like structures increased and the length and the breadth of pore-like structures also increased gradually. Pore-like structures changed statistically significantly in response to α-MSH stimulation. Further study will be needed to clarify whether the nature of pore-like structures is related to movement of melanosomes.

  1. TFAP2 paralogs regulate melanocyte differentiation in parallel with MITF

    PubMed Central

    Loftus, Stacie K.; Liu, Huan; Sompallae, Ramakrishna; Gildea, Derek E.; Santana, Juan F.; Manak, J. Robert; Pavan, William J.; Williams, Trevor; Cornell, Robert A.

    2017-01-01

    Mutations in the gene encoding transcription factor TFAP2A result in pigmentation anomalies in model organisms and premature hair graying in humans. However, the pleiotropic functions of TFAP2A and its redundantly-acting paralogs have made the precise contribution of TFAP2-type activity to melanocyte differentiation unclear. Defining this contribution may help to explain why TFAP2A expression is reduced in advanced-stage melanoma compared to benign nevi. To identify genes with TFAP2A-dependent expression in melanocytes, we profile zebrafish tissue and mouse melanocytes deficient in Tfap2a, and find that expression of a small subset of genes underlying pigmentation phenotypes is TFAP2A-dependent, including Dct, Mc1r, Mlph, and Pmel. We then conduct TFAP2A ChIP-seq in mouse and human melanocytes and find that a much larger subset of pigmentation genes is associated with active regulatory elements bound by TFAP2A. These elements are also frequently bound by MITF, which is considered the “master regulator” of melanocyte development. For example, the promoter of TRPM1 is bound by both TFAP2A and MITF, and we show that the activity of a minimal TRPM1 promoter is lost upon deletion of the TFAP2A binding sites. However, the expression of Trpm1 is not TFAP2A-dependent, implying that additional TFAP2 paralogs function redundantly to drive melanocyte differentiation, which is consistent with previous results from zebrafish. Paralogs Tfap2a and Tfap2b are both expressed in mouse melanocytes, and we show that mouse embryos with Wnt1-Cre-mediated deletion of Tfap2a and Tfap2b in the neural crest almost completely lack melanocytes but retain neural crest-derived sensory ganglia. These results suggest that TFAP2 paralogs, like MITF, are also necessary for induction of the melanocyte lineage. Finally, we observe a genetic interaction between tfap2a and mitfa in zebrafish, but find that artificially elevating expression of tfap2a does not increase levels of melanin in mitfa

  2. Involvement of the neural stem cell compartment by pediatric and adult gliomas: a retrospective review of 377 cases.

    PubMed

    Marsh, James C; Goldman, Stewart; Ziel, Ellis; Bregman, Corey; Diaz, Aidnag; Byrne, Richard; Fangusaro, Jason

    2015-03-01

    To assess frequency of neural stem cell compartment (NSC) involvement in adult and pediatric gliomas [World Health Organization (WHO) grades 1-4], and to assess whether NSC involvement at presentation impacts on survival, recurrence rates, and/or transformation from low grade (WHO grade 1-2) to high grade disease (WHO grades 3-4). Cranial MRIs for 154 pediatric and 223 adult glioma patients treated from 2000 to 2012 were reviewed. NSC involvement was documented. Tumors were stratified by age (adult vs. pediatric), histology, tumor grade, tumor location, and involvement of midline structures. Odds ratios (OR) for death were calculated based on NSC status at presentation. Rates of transformation and recurrence rates (ORR) were compared using Fisher's Exact Test. Time to recurrence (TTR) was calculated using student t test. Among recurrent and transformed tumors, we also assessed the rate of NSC involvement at time of recurrence or transformation. 74.8 % of tumors had NSC involvement. Higher rates of NSC involvement were seen among adult (p = .0001); high grade (p = .0001)); grade 2 versus grade 1 (p = .0001) and other grade 1 histologies (p = .0001) versus JPA (juvenile pilocytic astrocytoma) patients); grade 2-4 tumors (p = .0001); and supratentorial tumors (p < .0001). No transformation was noted among pediatric low grade tumors or adult grade 1 tumors. 22/119 (18.5 %) adult grade 2 tumors transformed. Rates of transformation were not impacted by NSC status (p = .47). ORR was 15.1 %, and was greater for NSC+ tumors at presentation (p = .05). 36/41 recurrences (87.8 %) involved NSC at time of recurrence. OR for death was 2.62 (1.16-5.9), p = .02 for NSC+ tumors at presentation. Adult and pediatric gliomas (all grades) frequently involve NSC at presentation, although rates are lower in pediatric JPA and all infratentorial tumors. NSC involvement at presentation increases OR death and reduces TTR for pediatric gliomas (all grades) and adult low grade gliomas, and

  3. Effect of continuous gamma-radiation on the stem and differentiating spermatogonia of the adult rat.

    PubMed

    Erickson, B H

    1978-10-01

    Sprague-Dawley rats were irradiated continuously (60Co, gamma) at a dose-rate of either 1 (0.0007 rad/min), 3 or 6 rad/23-h day for monthly intervals of 1 to 6. At one month after irradiation, counts of differentiating spermatogonia (A1 and A4) were reduced to a level that remained essentially unchanged during the succeeding 5 months of irradiation. The magnitude of the irradiation effect was greatest at stage 1 of the spermatogenic cycle where numbers of differentiating spermatogonia were reduced to 50% of control by 1 rad/day and to 30 and 20% of control by 3 and 6 rad/day, respectively. Number of stem spermatogonia was not significantly affected by 1 rad/day (P greater than 0.10). At 3 and 6 rad, however, number of stem cells declined from 80% of control at 1 month to 60 and 40% of control at 6 months, respectively. At a dose-rate of 1 rad/day there was neither a reduction in number of A1 spermatogonia per clone nor significant evidence of necrosis among either stem or differentiating spermatogonia; therefore, a reduction of stem-cell mitotic activity appears to be the principal effect of continuous low-level irradiation on spermatogenesis in the rat.

  4. Clonal proliferation of multipotent stem/progenitor cells in the neonatal and adult salivary glands

    SciTech Connect

    Kishi, Teruki; Takao, Tukasa; Fujita, Kiyohide; Taniguchi, Hideki . E-mail: rtanigu@med.yokohama-cu.ac.jp

    2006-02-10

    Salivary gland stem/progenitor cells are thought to be present in intercalated ductal cells, but the fact is unclear. In this study, we sought to clarify if stem/progenitor cells are present in submandibular glands using colony assay, which is one of the stem cell assay methods. Using a low-density culture of submandibular gland cells of neonatal rats, we developed a novel culture system that promotes single cell colony formation. Average doubling time for the colony-forming cells was 24.7 (SD = {+-}7.02) h, indicating high proliferative potency. When epidermal growth factor (EGF) and hepatocyte growth factor (HGF) were added to the medium, the number of clonal colonies increased greater than those cultured without growth factors (13.2 {+-} 4.18 vs. 4.5 {+-} 1.73). The RT-PCR and immunostaining demonstrated expressing acinar, ductal, and myoepithelial cell lineage markers. This study demonstrated the presence of the salivary gland stem/progenitor cells that are highly proliferative and multipotent in salivary glands.

  5. Transcranial Magnetic Stimulation of Human Adult Stem Cells in the Mammalian Brain

    PubMed Central

    Kremer, Karlea L.; Smith, Ashleigh E.; Sandeman, Lauren; Inglis, Joshua M.; Ridding, Michael C.; Koblar, Simon A.

    2016-01-01

    Introduction: The burden of stroke on the community is growing, and therefore, so is the need for a therapy to overcome the disability following stroke. Cellular-based therapies are being actively investigated at a pre-clinical and clinical level. Studies have reported the beneficial effects of exogenous stem cell implantation, however, these benefits are also associated with limited survival of implanted stem cells. This exploratory study investigated the use of transcranial magnetic stimulation (TMS) as a complementary therapy to increase stem cell survival following implantation of human dental pulp stem cells (DPSC) in the rodent cortex. Methods: Sprague-Dawley rats were anesthetized and injected with 6 × 105 DPSC or control media via an intracranial injection, and then received real TMS (TMS0.2 Hz) or sham TMS (TMSsham) every 2nd day beginning on day 3 post DPSC injection for 2 weeks. Brain sections were analyzed for the survival, migration and differentiation characteristics of the implanted cells. Results: In animals treated with DPSC and TMS0.2 Hz there were significantly less implanted DPSC and those that survived remained in the original cerebral hemisphere compared to animals that received TMSsham. The surviving implanted DPSC in TMS0.2 Hz were also found to express the apoptotic marker Caspase-3. Conclusions: We suggest that TMS at this intensity may cause an increase in glutamate levels, which promotes an unfavorable environment for stem cell implantation, proliferation and differentiation. It should be noted that only one paradigm of TMS was tested as this was conducted as a exploratory study, and further TMS paradigms should be investigated in the future. PMID:27013982

  6. p38α MAPK regulates adult muscle stem cell fate by restricting progenitor proliferation during postnatal growth and repair.

    PubMed

    Brien, Patrick; Pugazhendhi, Dhamayanthi; Woodhouse, Samuel; Oxley, David; Pell, Jennifer M

    2013-08-01

    Stem cell function is essential for the maintenance of adult tissue homeostasis. Controlling the balance between self-renewal and differentiation is crucial to maintain a receptive satellite cell pool capable of responding to growth and regeneration cues. The mitogen-activated protein kinase p38α has been implicated in the regulation of these processes but its influence in adult muscle remains unknown. Using conditional satellite cell p38α knockout mice we have demonstrated that p38α restricts excess proliferation in the postnatal growth phase while promoting timely myoblast differentiation. Differentiation was still able to occur in the p38α-null satellite cells, however, but was delayed. An absence of p38α resulted in a postnatal growth defect along with the persistence of an increased reservoir of satellite cells into adulthood. This population was still capable of responding to cardiotoxin-induced injury, resulting in complete, albeit delayed, regeneration, with further enhancement of the satellite cell population. Increased p38γ phosphorylation accompanied the absence of p38α, and inhibition of p38γ ex vivo substantially decreased the myogenic defect. We have used genome-wide transcriptome analysis to characterize the changes in expression that occur between resting and regenerating muscle, and the influence p38α has on these expression profiles. This study provides novel evidence for the fundamental role of p38α in adult muscle homeostasis in vivo.

  7. Muse Cells Derived from Dermal Tissues Can Differentiate into Melanocytes.

    PubMed

    Tian, Ting; Zhang, Ru-Zhi; Yang, Yu-Hua; Liu, Qi; Li, Di; Pan, Xiao-Ru

    2017-02-07

    The objective of the authors has been to obtain multilineage-differentiating stress-enduring cells (Muse cells) from primary cultures of dermal fibroblasts, identify their pluripotency, and detect their ability to differentiate into melanocytes. The distribution of SSEA-3-positive cells in human scalp skin was assessed by immunohistochemistry, and the distribution of Oct4, Sox2, Nanog, and SSEA-3-positive cells was determined by immunofluorescence staining. The expression levels of Sox2, Oct4, hKlf4, and Nanog mRNAs and proteins in Muse cells were determined by reverse transcription polymerase chain reaction (RT-PCR) analyses and Western blots, respectively. These Muse cells differentiated into melanocytes in differentiation medium. The SSEA-3-positive cells were scattered in the basement membrane zone and the dermis, with comparatively more in the sebaceous glands, vascular and sweat glands, as well as the outer root sheath of hair follicles, the dermal papillae, and the hair bulbs. Muse cells, which have the ability to self-renew, were obtained from scalp dermal fibroblasts by flow cytometry sorting with an anti-SSEA-3 antibody. The results of RT-PCR, Western blot, and immunofluorescence staining showed that the expression levels of Oct4, Nanog, Sox2, and Klf4 mRNAs and proteins in Muse cells were significantly different from their parental dermal fibroblasts. Muse cells differentiated into melanocytes when cultured in melanocyte differentiation medium, and the Muse cell-derived melanocytes expressed the melanocyte-specific marker HMB45. Muse cells could be obtained by flow cytometry from primary cultures of scalp dermal fibroblasts, which possessed the ability of pluripotency and self-renewal, and could differentiate into melanocytes in vitro.

  8. Inhibition of the histone demethylase Kdm5b promotes neurogenesis and derepresses Reln (reelin) in neural stem cells from the adult subventricular zone of mice.

    PubMed

    Zhou, Qiong; Obana, Edwin A; Radomski, Kryslaine L; Sukumar, Gauthaman; Wynder, Christopher; Dalgard, Clifton L; Doughty, Martin L

    2016-02-15

    The role of epigenetic regulators in the control of adult neurogenesis is largely undefined. We show that the histone demethylase enzyme Kdm5b (Jarid1b) negatively regulates neurogenesis from adult subventricular zone (SVZ) neural stem cells (NSCs) in culture. shRNA-mediated depletion of Kdm5b in proliferating adult NSCs decreased proliferation rates and reduced neurosphere formation in culture. When transferred to differentiation culture conditions, Kdm5b-depleted adult NSCs migrated from neurospheres with increased velocity. Whole-genome expression screening revealed widespread transcriptional changes with Kdm5b depletion, notably the up-regulation of reelin (Reln), the inhibition of steroid biosynthetic pathway component genes and the activation of genes with intracellular transport functions in cultured adult NSCs. Kdm5b depletion increased extracellular reelin concentration in the culture medium and increased phosphorylation of the downstream reelin signaling target Disabled-1 (Dab1). Sequestration of extracellular reelin with CR-50 reelin-blocking antibodies suppressed the increase in migratory velocity of Kdm5b-depleted adult NSCs. Chromatin immunoprecipitation revealed that Kdm5b is present at the proximal promoter of Reln, and H3K4me3 methylation was increased at this locus with Kdm5b depletion in differentiating adult NSCs. Combined the data suggest Kdm5b negatively regulates neurogenesis and represses Reln in neural stem cells from the adult SVZ.

  9. The circadian clock in skin: implications for adult stem cells, tissue regeneration, cancer, aging, and immunity

    PubMed Central

    Plikus, Maksim V.; Van Spyk, Elyse Noelani; Pham, Kim; Geyfman, Mikhail; Kumar, Vivek; Takahashi, Joseph S.; Andersen, Bogi

    2015-01-01

    Historically work on peripheral circadian clocks has been focused on organs and tissues that have prominent metabolic functions, such as liver, fat and muscle. In recent years, skin is emerging as a model for studying circadian clock regulation of cell proliferation, stem cell functions, tissue regeneration, aging and carcinogenesis. Morphologically skin is complex, containing multiple cell types and structures, and there is evidence for a functional circadian clock in most, if not all, of its cell types. Despite the complexity, skin stem cell populations are well defined, experimentally tractable and exhibit prominent daily cell proliferation cycles. Hair follicle stem cells also participate in recurrent, long-lasting cycles of regeneration -- the hair growth cycles. Among other advantages of skin is a broad repertoire of available genetic tools enabling the creation of cell-type specific circadian mutants. Also, due to the accessibility of the skin, in vivo imaging techniques can be readily applied to study the circadian clock and its outputs in real time, even at the single-cell level. Skin provides the first line of defense against many environmental and stress factors that exhibit dramatic diurnal variations such as solar UV radiation and temperature. Studies have already linked the circadian clock to the control of UVB-induced DNA damage and skin cancers. Due to the important role that skin plays in the defense against microorganisms, it represents a promising model system to further explore the role of the clock in the regulation of the body's immune functions. To that end, recent studies have already linked the circadian clock to psoriasis, one of the most common immune-mediated skin disorders. The skin also provides opportunities to interrogate clock regulation of tissue metabolism in the context of stem cells and regeneration. Furthermore, many animal species feature prominent seasonal hair molt cycles, offering an attractive model for investigating the

  10. The circadian clock in skin: implications for adult stem cells, tissue regeneration, cancer, aging, and immunity.

    PubMed

    Plikus, Maksim V; Van Spyk, Elyse N; Pham, Kim; Geyfman, Mikhail; Kumar, Vivek; Takahashi, Joseph S; Andersen, Bogi

    2015-06-01

    Historically, work on peripheral circadian clocks has been focused on organs and tissues that have prominent metabolic functions, such as the liver, fat, and muscle. In recent years, skin has emerged as a model for studying circadian clock regulation of cell proliferation, stem cell functions, tissue regeneration, aging, and carcinogenesis. Morphologically, skin is complex, containing multiple cell types and structures, and there is evidence for a functional circadian clock in most, if not all, of its cell types. Despite the complexity, skin stem cell populations are well defined, experimentally tractable, and exhibit prominent daily cell proliferation cycles. Hair follicle stem cells also participate in recurrent, long-lasting cycles of regeneration: the hair growth cycles. Among other advantages of skin is a broad repertoire of available genetic tools enabling the creation of cell type-specific circadian mutants. Also, due to the accessibility of skin, in vivo imaging techniques can be readily applied to study the circadian clock and its outputs in real time, even at the single-cell level. Skin provides the first line of defense against many environmental and stress factors that exhibit dramatic diurnal variations such as solar ultraviolet (UV) radiation and temperature. Studies have already linked the circadian clock to the control of UVB-induced DNA damage and skin cancers. Due to the important role that skin plays in the defense against microorganisms, it also represents a promising model system to further explore the role of the clock in the regulation of the body's immune functions. To that end, recent studies have already linked the circadian clock to psoriasis, one of the most common immune-mediated skin disorders. Skin also provides opportunities to interrogate the clock regulation of tissue metabolism in the context of stem cells and regeneration. Furthermore, many animal species feature prominent seasonal hair molt cycles, offering an attractive model

  11. Physicochemical Control of Adult Stem Cell Differentiation: Shedding Light on Potential Molecular Mechanisms

    DTIC Science & Technology

    2010-01-01

    applications, including tissue engineering, requires an understanding of the cell-cell and cell-environment interactions. To this end, recent efforts have been...restricted locations to allow continuation of the cycle of life [1]. These tissue -specific stem cells have been identified in the bone marrow [2], brain [3...relatively easy to isolate and differentiate into neuronal cells, and therefore may be useful for tissue engineering strategies to repair and regenerate

  12. High neuronal/astroglial differentiation plasticity of adult rat hippocampal neural stem/progenitor cells in response to the effects of embryonic and adult cerebrospinal fluids

    PubMed Central

    Peirouvi, T.; Yekani, F.; Azarnia, M.; Massumi, M.

    2015-01-01

    Hippocampal neural stem/progenitor cells (hipp-NS/PCs) of the adult mammalian brain are important sources of neuronal and gial cell production. In this study, the main goal is to investigate the plasticity of these cells in neuronal/astroglial differentiations. To this end, the differentiation of the hipp-NS/PCs isolated from 3-month-old Wistar rats was investigated in response to the embryonic cerebrospinal fluid (E-CSF) including E13.5, E17-CSF and the adult cerebrospinal fluid (A-CSF), all extracted from rats. CSF samples were selected based on their effects on cell behavioral parameters. Primary cell culture was performed in the presence of either normal or high levels of KCL in a culture medium. High levels of KCL cause cell depolarization, and thus the activation of quiescent NSCs. Results from immunocytochemistry (ICC) and semi-quantitative RT-PCR (sRT-PCR) techniques showed that in E-CSF-treated groups, neuronal differentiation increased (E17>E13.5). In contrast, A-CSF decreased and increased neuronal and astroglial differentiations, respectively. Cell survivability and/or proliferation (S/P), evaluated by an MTT assay, increased by E13.5 CSF, but decreased by both E17 CSF and A-CSF. Based on the results, it is finally concluded that adult rat hippocampal proliferative cells are not restricted progenitors but rather show high plasticity in neuronal/astroglial differentiation according to the effects of CSF samples. In addition, using high concentrations of KCL in the primary cell culture led to an increase in the number of NSCs, which in turn resulted in the increase in neuronal or astroglial differentiations after CSF treatment. PMID:27175157

  13. Human fallopian tube: a new source of multipotent adult mesenchymal stem cells discarded in surgical procedures

    PubMed Central

    Jazedje, Tatiana; Perin, Paulo M; Czeresnia, Carlos E; Maluf, Mariangela; Halpern, Silvio; Secco, Mariane; Bueno, Daniela F; Vieira, Natassia M; Zucconi, Eder; Zatz, Mayana

    2009-01-01

    Background The possibility of using stem cells for regenerative medicine has opened a new field of investigation. The search for sources to obtain multipotent stem cells from discarded tissues or through non-invasive procedures is of great interest. It has been shown that mesenchymal stem cells (MSCs) obtained from umbilical cords, dental pulp and adipose tissue, which are all biological discards, are able to differentiate into muscle, fat, bone and cartilage cell lineages. The aim of this study was to isolate, expand, characterize and assess the differentiation potential of MSCs from human fallopian tubes (hFTs). Methods Lineages of hFTs were expanded, had their karyotype analyzed, were characterized by flow cytometry and underwent in vitro adipogenic, chondrogenic, osteogenic, and myogenic differentiation. Results Here we show for the first time that hFTs, which are discarded after some gynecological procedures, are a rich additional source of MSCs, which we designated as human tube MSCs (htMSCs). Conclusion Human tube MSCs can be easily isolated, expanded in vitro, present a mesenchymal profile and are able to differentiate into muscle, fat, cartilage and bone in vitro. PMID:19538712

  14. Participation of adult bone marrow-derived stem cells in pancreatic regeneration: neogenesis versus endogenesis.

    PubMed

    Iskovich, Svetlana; Kaminitz, Ayelet; Yafe, Michal Pearl; Mizrahi, Keren; Stein, Jerry; Yaniv, Isaac; Askenasy, Nadir

    2007-12-01

    Regenerative medicine opens new avenues and promises towards more effective therapies for autoimmune disorders. Current therapeutic strategies for type I diabetes focus on three major directions, with distinct advantages and disadvantages: arrest of autoimmunity, islet transplantation and generation of neoislets. There is mounting evidence that candidate stem cells residing in the hematopoietic compartments participate in regeneration of pancreatic islets following chemical and autoimmune injury in vivo. The apparent major mechanisms include immunomodulation, revascularization, support of endogenous beta-cell regeneration and differentiation into insulin-producing cells. Review of the current evidence suggests that some divergent observations depend primarily on the experimental design, which both limits and accentuates developmental events. The flood of publications reporting negative results appears to reflect primarily suboptimal experimental conditions for differentiation of putative stem cells, rather than limited developmental plasticity. Stem cells modulate the course of autoimmune diabetes through multiple mechanisms, including de novo generation of units capable to sense, produce and secrete insulin. Therefore, the charged debate over controversies surrounding developmental plasticity should not impede attempts to design curative therapies for this disease.

  15. Autologous stem cell transplantation versus alternative allogeneic donor transplants in adult acute leukemias.

    PubMed

    Claude Gorin, Norbert

    2016-04-01

    The availability of alternative sources of stem cells including most recently T-replete haploidentical marrow or peripheral blood, and the increasing use of reduced-intensity conditioning (RIC), renders feasible an allogeneic transplant to almost all patients with acute leukemia up to 70 years of age. Autologous stem cell transplantation (ASCT) for consolidation of complete remission (CR), however, offers in some circumstances an alternative option. Although associated with a higher relapse rate, autologous transplant benefits from a lower non-relapse mortality, the absence of graft-versus-host disease (GVHD), and a better quality of life for long-term survivors. The recent use of intravenous busulfan (IVBU) with high-dose melphalan, better monitoring of minimal residual disease (MRD), and maintenance therapy post autografting bring new interest. Few retrospective studies compared the outcome following alternative donor versus autologous transplants for remission consolidation. Genoidentical and phenoidentical allogeneic stem cell transplantations are undisputed gold standards, but there are no data showing the superiority of alternative allogeneic donor over autologous transplantation, at the time of undetectable MRD, in patients with good- and intermediate-1 risk acute myelocytic leukemia (AML) in first complete remission (CR1), acute promyelocytic leukemia in second complete remission (CR2), and Philadelphia chromosome-positive (Ph(+)) acute lymphocytic leukemia (ALL).

  16. Successful Cord Blood Stem Cell Transplantation for an Adult Case of Chronic Active Epstein-Barr Virus Infection

    PubMed Central

    Saburi, Masuho; Ogata, Masao; Satou, Takako; Yoshida, Natsumi; Nagamatsu, Kentaro; Nashimoto, Yuko; Moroga, Yui; Takano, Kuniko; Kohno, Kazuhiro; Shirao, Kuniaki

    2016-01-01

    A 41-year-old man was referred to our hospital for treatment of anaplastic lymphoma kinase (ALK)-negative anaplastic large cell lymphoma. Chronic active Epstein-Barr virus (CAEBV) was diagnosed based on the findings of elevated EBV antibody titers and positive EBV-DNA in the peripheral blood, and cord blood stem cell transplantation (CBT) was performed. The EBV-DNA levels in the blood fell below the limit of detection. His lymphoma relapsed on Day 165 with the appearance of eruptions, which disappeared after the withdrawal of tacrolimus. One year after transplantation, there were no signs of recurrence. This encouraging result suggests that CBT should be considered for adult cases of CAEBV with aggressive clinical manifestations. PMID:27904117

  17. Recent insights into the molecular mechanisms involved in aging and the malignant transformation of adult stem/progenitor cells and their therapeutic implications

    PubMed Central

    Mimeault, Murielle; Batra, Surinder K.

    2013-01-01

    Recent advancements in tissue-resident adult stem/progenitor cell research have revealed that enhanced telomere attrition, oxidative stress, ultraviolet radiation exposure and oncogenic events leading to severe DNA damages and genomic instability may occur in these immature and regenerative cells during chronological aging. Particularly, the alterations in key signaling components controlling their self-renewal capacity and an up-regulation of tumor suppressor gene products such as p16INK4A, p19ARF, ataxia-telangiectasia mutated (ATM) kinase, p53and/or theforkhead box O (FOXOs) family of transcription factors may result in their dysfunctions, growth arrest and senescence or apoptotic death during the aging process. These molecular events may culminate in a progressive decline in the regenerative functions and the number of tissue-resident adult stem/progenitor cells, and age-related disease development. Conversely, the telomerase re-activation and accumulation of numerous genetic and/or epigenetic alterations in adult stem/progenitor cells with advancing age may result in their immortalization and malignant transformation into highly leukemic or tumorigenic cancer-initiating cells and cancer initiation. Therefore, the cell-replacement and gene therapies and molecular targeting of aged and dysfunctional adult stem/progenitor cells including their malignant counterpart, cancer-initiating cells, hold great promise for treating and even curing diverse devastating human diseases. These diseases include premature aging diseases, hematopoietic, cardiovascular, musculoskeletal, pulmonary, ocular, urogenital, neurodegenerative and skin disorders and aggressive and recurrent cancers. PMID:19114129

  18. Wnt inhibitory factor (WIF)-1 promotes melanogenesis in normal human melanocytes.

    PubMed

    Park, Tae Jun; Kim, Misun; Kim, Hyeran; Park, Sun Yi; Park, Kyoung-Chan; Ortonne, Jean-Paul; Kang, Hee Young

    2014-01-01

    Wnt signaling plays a role in the differentiation as well as the development of melanocytes. Using a microarray analysis, hyperpigmentary skin of melasma expressed high levels of Wnt inhibitory factor-1 (WIF-1) compared with perilesional normal skin. In this study, the expression and functional roles of WIF-1 on melanocytes were investigated. WIF-1 was expressed both in the melanocytes of normal human skin and in cultured melanocytes. The upregulation of WIF-1 on cultured normal human melanocytes significantly induced expressions of MITF and tyrosinase, which were associated with increased melanin content and tyrosinase activity. Consistent with the stimulatory effect of WIF-1, WIF-1 siRNA reduced melanogenesis in the cells. Moreover, WIF-1 increases pigmentation in melanocytes co-cultured with WIF-1-overexpressed fibroblasts and of organ-cultured human skin. These findings suggest that melanocytes express WIF-1 constitutively in vivo and in vitro and that WIF-1 promotes melanogenesis in normal human melanocytes.

  19. Alpha-melanocyte-stimulating hormone suppresses oxidative stress through a p53-mediated signaling pathway in human melanocytes.

    PubMed

    Kadekaro, Ana Luisa; Chen, Juping; Yang, Jennifer; Chen, Shuna; Jameson, Joshua; Swope, Viki B; Cheng, Tan; Kadakia, Madhavi; Abdel-Malek, Zalfa

    2012-06-01

    Epidermal melanocytes are skin cells specialized in melanin production. Activation of the melanocortin 1 receptor (MC1R) on melanocytes by α-melanocyte-stimulating hormone (α-MSH) induces synthesis of the brown/black pigment eumelanin that confers photoprotection from solar UV radiation (UVR). Contrary to keratinocytes, melanocytes are slow proliferating cells that persist in the skin for decades, in an environment with high levels of UVR-induced reactive oxygen species (ROS). We previously reported that in addition to its role in pigmentation, α-MSH also reduces oxidative stress and enhances the repair of DNA photoproducts in melanocytes, independent of melanin synthesis. Given the significance of ROS in carcinogenesis, here we investigated the mechanisms by which α-MSH exerts antioxidant effects in melanocytes. We show that activation of the MC1R by α-MSH contributes to phosphorylation of p53 on serine 15, a known requirement for stabilization and activation of p53, a major sensor of DNA damage. This effect is mediated by the cAMP/PKA pathway and by the activation of phosphoinositide 3-kinase (PI3K) ATR and DNA protein kinase (DNA-PK). α-MSH increases the levels of 8-oxoguanine DNA glycosylase (OGG1) and apurinic apyrimidinic endonuclease 1 (APE-1/Ref-1), enzymes essential for base excision repair. Nutlin-3, an HDM2 inhibitor, mimicked the effects of α-MSH resulting in reduced phosphorylation of H2AX (γ-H2AX), a marker of DNA damage. Conversely, the p53 inhibitor pifithrin-α or silencing of p53 abolished the effects of α-MSH and augmented oxidative stress. These results show that p53 is an important target of the downstream MC1R signaling that reduces oxidative stress and possibly malignant transformation of melanocytes.

  20. Effects of FGF-2 on human adipose tissue derived adult stem cells morphology and chondrogenesis enhancement in Transwell culture

    SciTech Connect

    Kabiri, Azadeh; Esfandiari, Ebrahim; Hashemibeni, Batool; Kazemi, Mohammad; Mardani, Mohammad; Esmaeili, Abolghasem

    2012-07-27

    Highlights: Black-Right-Pointing-Pointer We investigated effects of FGF-2 on hADSCs. Black-Right-Pointing-Pointer We examine changes in the level of gene expressions of SOX-9, aggrecan and collagen type II and type X. Black-Right-Pointing-Pointer FGF-2 induces chondrogenesis in hADSCs, which Bullet Increasing information will decrease quality if hospital costs are very different. Black-Right-Pointing-Pointer The result of this study may be beneficial in cartilage tissue engineering. -- Abstract: Injured cartilage is difficult to repair due to its poor vascularisation. Cell based therapies may serve as tools to more effectively regenerate defective cartilage. Both adult mesenchymal stem cells (MSCs) and human adipose derived stem cells (hADSCs) are regarded as potential stem cell sources able to generate functional cartilage for cell transplantation. Growth factors, in particular the TGF-b superfamily, influence many processes during cartilage formation, including cell proliferation, extracellular matrix synthesis, maintenance of the differentiated phenotype, and induction of MSCs towards chondrogenesis. In the current study, we investigated the effects of FGF-2 on hADSC morphology and chondrogenesis in Transwell culture. hADSCs were obtained from patients undergoing elective surgery, and then cultured in expansion medium alone or in the presence of FGF-2 (10 ng/ml). mRNA expression levels of SOX-9, aggrecan and collagen type II and type X were quantified by real-time polymerase chain reaction. The morphology, doubling time, trypsinization time and chondrogenesis of hADSCs were also studied. Expression levels of SOX-9, collagen type II, and aggrecan were all significantly increased in hADSCs expanded in presence of FGF-2. Furthermore FGF-2 induced a slender morphology, whereas doubling time and trypsinization time decreased. Our results suggest that FGF-2 induces hADSCs chondrogenesis in Transwell culture, which may be beneficial in cartilage tissue engineering.

  1. T-cell-replete haploidentical transplantation versus autologous stem cell transplantation in adult acute leukemia: a matched pair analysis.

    PubMed

    Gorin, Norbert-Claude; Labopin, Myriam; Piemontese, Simona; Arcese, William; Santarone, Stella; Huang, He; Meloni, Giovanna; Ferrara, Felicetto; Beelen, Dietrich; Sanz, Miguel; Bacigalupo, Andrea; Ciceri, Fabio; Mailhol, Audrey; Nagler, Arnon; Mohty, Mohamad

    2015-04-01

    Adult patients with acute leukemia in need of a transplant but without a genoidentical donor are usually considered upfront for transplantation with stem cells from any other allogeneic source, rather than autologous stem cell transplantation. We used data from the European Society for Blood and Marrow Transplantation and performed a matched pair analysis on 188 T-cell-replete haploidentical and 356 autologous transplants done from January 2007 to December 2012, using age, diagnosis, disease status, cytogenetics, and interval from diagnosis to transplant as matching factors. "Haploidentical expert" centers were defined as having reported more than five haploidentical transplants for acute leukemia (median value for the study period). The median follow-up was 28 months. Multivariate analyses, including type of transplant categorized into three classes ("haploidentical regular", "haploidentical expert" and autologous), conditioning intensity (reduced intensity versus myeloablative conditioning) and the random effect taking into account associations related to matching, showed that non-relapse mortality was higher following haploidentical transplants in expert (HR: 4.7; P=0.00004) and regular (HR: 8.98; P<10(-5)) centers. Relapse incidence for haploidentical transplants was lower in expert centers (HR:0.39; P=0.0003) but in regular centers was similar to that for autologous transplants. Leukemia-free survival and overall survival rates were higher following autologous transplantation than haploidentical transplants in regular centers (HR: 1.63; P=0.008 and HR: 2.31; P=0.0002 respectively) but similar to those following haploidentical transplants in expert centers. We conclude that autologous stem cell transplantation should presently be considered as a possible alternative to haploidentical transplantation in regular centers that have not developed a specific expert program.

  2. OPLA scaffold, collagen I, and horse serum induce an higher degree of myogenic differentiation of adult rat cardiac stem cells.

    PubMed

    Di Felice, Valentina; Ardizzone, Nella Maria; De Luca, Angela; Marcianò, Vito; Marino Gammazza, Antonella; Macaluso, Filippo; Manente, Lucrezia; Cappello, Francesco; De Luca, Antonio; Zummo, Giovanni

    2009-12-01

    In the last few years, a major goal of cardiac research has been to drive stem cell differentiation to replace damaged myocardium. Several research groups have attempted to differentiate potential cardiac stem cells (CSCs) using bi- or three-dimensional systems supplemented with growth factors or molecules acting as differentiating substances. We hypothesize that these systems failed to induce a complete differentiation because they lacked an architectural space. In the present study, we isolated a pool of small proliferating and fibroblast-like cells from adult rat myocardium. The phenotype of these cells was assessed and the characterized cells were cultured in a collagen I/OPLA scaffold with horse serum to obtain fine myocardial differentiation. C-Kit(POS)/Sca-1(POS) CSCs fully differentiated in vitro when an environment more similar to the CSC niche was created. These experiments demonstrated an important model for the study of the biology of CSCs and the biochemical pathways that lead to myocardial differentiation. The results pave the way for a new surgical approach.

  3. Calpain Determines the Propensity of Adult Hippocampal Neural Stem Cells to Autophagic Cell Death Following Insulin Withdrawal.

    PubMed

    Chung, Kyung Min; Park, Hyunhee; Jung, Seonghee; Ha, Shinwon; Yoo, Seung-Jun; Woo, Hanwoong; Lee, Hyang Ju; Kim, Seong Who; Kim, Eun-Kyoung; Moon, Cheil; Yu, Seong-Woon

    2015-10-01

    Programmed cell death (PCD) has significant effects on the function of neural stem cells (NSCs) during brain development and degeneration. We have previously reported that adult rat hippocampal neural stem (HCN) cells underwent autophagic cell death (ACD) rather than apoptosis following insulin withdrawal despite their intact apoptotic capabilities. Here, we report a switch in the mode of cell death in HCN cells with calpain as a critical determinant. In HCN cells, calpain 1 expression was barely detectable while calpain 2 was predominant. Inhibition of calpain in insulin-deprived HCN cells further augmented ACD. In contrast, expression of calpain 1 switched ACD to apoptosis. The proteasome inhibitor lactacystin blocked calpain 2 degradation and elevated the intracellular Ca(2+) concentration. In combination, these effects potentiated calpain activity and converted the mode of cell death to apoptosis. Our results indicate that low calpain activity, due to absence of calpain 1 and degradation of calpain 2, results in a preference for ACD over apoptosis in insulin-deprived HCN cells. On the other hand, conditions leading to high calpain activity completely switch the mode of cell death to apoptosis. This is the first report on the PCD mode switching mechanism in NSCs. The dynamic change in calpain activity through the proteasome-mediated modulation of the calpain and intracellular Ca(2+) levels may be the critical contributor to the demise of NSCs. Our findings provide a novel insight into the complex mechanisms interconnecting autophagy and apoptosis and their roles in the regulation of NSC death.

  4. Estrogenic Exposure Alters the Spermatogonial Stem Cells in the Developing Testis, Permanently Reducing Crossover Levels in the Adult

    PubMed Central

    Vrooman, Lisa A.; Oatley, Jon M.; Griswold, Jodi E.; Hassold, Terry J.; Hunt, Patricia A.

    2015-01-01

    Bisphenol A (BPA) and other endocrine disrupting chemicals have been reported to induce negative effects on a wide range of physiological processes, including reproduction. In the female, BPA exposure increases meiotic errors, resulting in the production of chromosomally abnormal eggs. Although numerous studies have reported that estrogenic exposures negatively impact spermatogenesis, a direct link between exposures and meiotic errors in males has not been evaluated. To test the effect of estrogenic chemicals on meiotic chromosome dynamics, we exposed male mice to either BPA or to the strong synthetic estrogen, ethinyl estradiol during neonatal development when the first cells initiate meiosis. Although chromosome pairing and synapsis were unperturbed, exposed outbred CD-1 and inbred C3H/HeJ males had significantly reduced levels of crossovers, or meiotic recombination (as defined by the number of MLH1 foci in pachytene cells) by comparison with placebo. Unexpectedly, the effect was not limited to cells exposed at the time of meiotic entry but was evident in all subsequent waves of meiosis. To determine if the meiotic effects induced by estrogen result from changes to the soma or germline of the testis, we transplanted spermatogonial stem cells from exposed males into the testes of unexposed males. Reduced recombination was evident in meiocytes derived from colonies of transplanted cells. Taken together, our results suggest that brief exogenous estrogenic exposure causes subtle changes to the stem cell pool that result in permanent alterations in spermatogenesis (i.e., reduced recombination in descendent meiocytes) in the adult male. PMID:25615633

  5. Rescue of retinal degeneration by intravitreally injected adult bone marrow–derived lineage-negative hematopoietic stem cells

    PubMed Central

    Otani, Atsushi; Dorrell, Michael Ian; Kinder, Karen; Moreno, Stacey K.; Nusinowitz, Steven; Banin, Eyal; Heckenlively, John; Friedlander, Martin

    2004-01-01

    Inherited retinal degenerations afflict 1 in 3,500 individuals and are a heterogeneous group of diseases that result in profound vision loss, usually the result of retinal neuronal apoptosis. Atrophic changes in the retinal vasculature are also observed in many of these degenerations. While it is thought that this atrophy is secondary to diminished metabolic demand in the face of retinal degeneration, the precise relationship between the retinal neuronal and vascular degeneration is not clear. In this study we demonstrate that whenever a fraction of mouse or human adult bone marrow–derived stem cells (lineage-negative hematopoietic stem cells [Lin– HSCs]) containing endothelial precursors stabilizes and rescues retinal blood vessels that would ordinarily completely degenerate, a dramatic neurotrophic rescue effect is also observed. Retinal nuclear layers are preserved in 2 mouse models of retinal degeneration, rd1 and rd10, and detectable, albeit severely abnormal, electroretinogram recordings are observed in rescued mice at times when they are never observed in control-treated or untreated eyes. The normal mouse retina consists predominantly of rods, but the rescued cells after treatment with Lin– HSCs are nearly all cones. Microarray analysis of rescued retinas demonstrates significant upregulation of many antiapoptotic genes, including small heat shock proteins and transcription factors. These results suggest a new paradigm for thinking about the relationship between vasculature and associated retinal neuronal tissue as well as a potential treatment for delaying the progression of vision loss associated with retinal degeneration regardless of the underlying genetic defect. PMID:15372100

  6. Reduced-intensity hematopoietic stem-cell transplantation for malignant lymphoma: a retrospective survey of 112 adult patients in Japan.

    PubMed

    Kusumi, E; Kami, M; Kanda, Y; Murashige, N; Kishi, Y; Suzuki, R; Takeuchi, K; Tanimoto, T E; Mori, T; Muta, K; Tamaki, T; Tanaka, Y; Ogawa, H; Yamane, T; Taniguchi, S; Takaue, Y

    2005-08-01

    We conducted a nation-wide survey of 112 adult Japanese patients who underwent reduced-intensity stem cell transplantation (RIST) from 1999 to 2002. Underlying diseases included indolent (n=45), aggressive (n=58) and highly aggressive lymphomas (n=9). Median age of the patients was 49 years. A total of 40 patients (36%) had relapsed diseases after autologous stem cell transplantation and 36 patients (32%) had received radiotherapy. RIST regimens were fludarabine-based (n=95), low-dose total body irradiation-based (n=6) and others (n=11). Cumulative incidences of grade II-IV acute graft-versus-host disease (GVHD) and chronic GVHD were, respectively, 49 and 59%. Cumulative incidences of progression and progression-free mortality were 18 and 25%, respectively. With a median follow-up of 23.9 months, 3-year overall survival rates were 59%. A multivariate analysis identified three significant factors for progression, which are history of radiation (relative risk (RR) 3.45, confidential interval (CI) 1.12-10.0, P=0.03), central nervous system involvement (RR 6.25, CI 2.08-20.0, P=0.001) and development of GVHD (RR 0.28, CI 0.090-0.86, P=0.026). RIST may have decreased the rate of transplant-related mortality, and GVHD may have induced a graft-versus-lymphoma effect. However, whether or not these potential benefits can be directly translated into improved patient survival should be evaluated in further studies.

  7. Adult zebrafish intestine resection: a novel model of short bowel syndrome, adaptation, and intestinal stem cell regeneration.

    PubMed

    Schall, K A; Holoyda, K A; Grant, C N; Levin, D E; Torres, E R; Maxwell, A; Pollack, H A; Moats, R A; Frey, M R; Darehzereshki, A; Al Alam, D; Lien, C; Grikscheit, T C

    2015-08-01

    Loss of significant intestinal length from congenital anomaly or disease may lead to short bowel syndrome (SBS); intestinal failure may be partially offset by a gain in epithelial surface area, termed adaptation. Current in vivo models of SBS are costly and technically challenging. Operative times and survival rates have slowed extension to transgenic models. We created a new reproducible in vivo model of SBS in zebrafish, a tractable vertebrate model, to facilitate investigation of the mechanisms of intestinal adaptation. Proximal intestinal diversion at segment 1 (S1, equivalent to jejunum) was performed in adult male zebrafish. SBS fish emptied distal intestinal contents via stoma as in the human disease. After 2 wk, S1 was dilated compared with controls and villus ridges had increased complexity, contributing to greater villus epithelial perimeter. The number of intervillus pockets, the intestinal stem cell zone of the zebrafish increased and contained a higher number of bromodeoxyuridine (BrdU)-labeled cells after 2 wk of SBS. Egf receptor and a subset of its ligands, also drivers of adaptation, were upregulated in SBS fish. Igf has been reported as a driver of intestinal adaptation in other animal models, and SBS fish exposed to a pharmacological inhibitor of the Igf receptor failed to demonstrate signs of intestinal adaptation, such as increased inner epithelial perimeter and BrdU incorporation. We describe a technically feasible model of human SBS in the zebrafish, a faster and less expensive tool to investigate intestinal stem cell plasticity as well as the mechanisms that drive intestinal adaptation.

  8. Small Fractions of Muscular Dystrophy Embryonic Stem Cells Yield Severe Cardiac and Skeletal Muscle Defects in Adult Mouse Chimeras.

    PubMed

    Gonzalez, J Patrick; Kyrychenko, Sergii; Kyrychenko, Viktoriia; Schneider, Joel S; Granier, Celine J; Himelman, Eric; Lahey, Kevin C; Zhao, Qingshi; Yehia, Ghassan; Tao, Yuan-Xiang; Bhaumik, Mantu; Shirokova, Natalia; Fraidenraich, Diego

    2017-03-01

    Duchenne muscular dystrophy (DMD) is characterized by the loss of the protein dystrophin, leading to muscle fragility, progressive weakening, and susceptibility to mechanical stress. Although dystrophin-negative mdx mouse models have classically been used to study DMD, phenotypes appear mild compared to patients. As a result, characterization of muscle pathology, especially in the heart, has proven difficult. We report that injection of mdx embryonic stem cells (ESCs) into Wild Type blastocysts produces adult mouse chimeras with severe DMD phenotypes in the heart and skeletal muscle. Inflammation, regeneration and fibrosis are observed at the whole organ level, both in dystrophin-negative and dystrophin-positive portions of the chimeric tissues. Skeletal and cardiac muscle function are also decreased to mdx levels. In contrast to mdx heterozygous carriers, which show no significant phenotypes, these effects are even observed in chimeras with low levels of mdx ESC incorporation (10%-30%). Chimeric mice lack typical compensatory utrophin upregulation, and show pathological remodeling of Connexin-43. In addition, dystrophin-negative and dystrophin-positive isolated cardiomyocytes show augmented calcium response to mechanical stress, similar to mdx cells. These global effects highlight a novel role of mdx ESCs in triggering muscular dystrophy even when only low amounts are present. Stem Cells 2017;35:597-610.

  9. Neural Stem Cells in the Adult Subventricular Zone Oxidize Fatty Acids to Produce Energy and Support Neurogenic Activity

    PubMed Central

    Makin, Rebecca; Sweet, Ian R.; Trevelyan, Andrew J.; Miwa, Satomi; Horner, Philip J.; Turnbull, Douglass M.

    2015-01-01

    Abstract Neural activity is tightly coupled to energy consumption, particularly sugars such as glucose. However, we find that, unlike mature neurons and astrocytes, neural stem/progenitor cells (NSPCs) do not require glucose to sustain aerobic respiration. NSPCs within the adult subventricular zone (SVZ) express enzymes required for fatty acid oxidation and show sustained increases in oxygen consumption upon treatment with a polyunsaturated fatty acid. NSPCs also demonstrate sustained decreases in oxygen consumption upon treatment with etomoxir, an inhibitor of fatty acid oxidation. In addition, etomoxir decreases the proliferation of SVZ NSPCs without affecting cellular survival. Finally, higher levels of neurogenesis can be achieved in aged mice by ectopically expressing proliferator‐activated receptor gamma coactivator 1 alpha (PGC1α), a factor that increases cellular aerobic capacity by promoting mitochondrial biogenesis and metabolic gene transcription. Regulation of metabolic fuel availability could prove a powerful tool in promoting or limiting cellular proliferation in the central nervous system. Stem Cells 2015;33:2306–2319 PMID:25919237

  10. Comparison of hematopoietic supportive capacity between human fetal and adult bone marrow mesenchymal stem cells in vitro.

    PubMed

    Liu, Meng; Yang, Shao-Guang; Xing, Wen; Lu, Shi-Hong; Zhao, Qin-Jun; Ren, Hong-Ying; Chi, Ying; Ma, Feng-Xia; Han, Zhong-Chao

    2011-08-01

    Hematopoietic stem cells (HSC) shift from fetal liver and spleen to bone marrow at neonatal stages and this movement may be due to inductive signals from different microenvironments. Mesenchymal stem cells (MSC) are the precursors of stromal cells in bone marrow microenvironments such as osteoblasts and endothelial cells. Some researchers speculated that fetal bone marrow before birth might be not perfectly suit HSC growth. However, it is still lack of direct evidence to prove this hypothesis. This study was aimed to compare the hematopoietic supportive capacity between human fetal and adult bone marrow MSC in vitro. Adult bone marrow MSC (ABM-MSC) were isolated from three healthy donors and fetal bone marrow MSC (FBM-MSC) were isolated from three fetuses between gestations of 19 to 20 weeks. After irradiation, MSC were co-cultured with CD34(+) cells isolated from umbilical cord blood in long-term culture-initiating cell (LTC-IC) assay. The colony number of colony forming cells (CFC) was counted and the phenotypic changes of co-cultured CD34(+) cells were analyzed by flow cytometry. Cytokine expressions in both kinds of MSC were detected by reverse transcription polymerase chain reaction (RT-PCR). The results showed that ABM-MSC had a stronger hematopoietic supportive capacity than FBM-MSC. Both of them enhanced the differentiation of CD34(+) cells into myeloid lineages. Cytokines were expressed differently in ABM-MSC and FBM-MSC. It is concluded that ABM-MSC possess more potential application in some treatments than FBM-MSC, especially in hematopoietic reconstitution.

  11. Gene Expression Profile of Adult Human Olfactory Bulb and Embryonic Neural Stem Cell Suggests Distinct Signaling Pathways and Epigenetic Control

    PubMed Central

    Marei, Hany E. S.; Ahmed, Abd-Elmaksoud; Michetti, Fabrizio; Pescatori, Mario; Pallini, Roberto; Casalbore, Patricia; Cenciarelli, Carlo; Elhadidy, Mohamed

    2012-01-01

    Global gene expression profiling was performed using RNA from human embryonic neural stem cells (hENSC), and adult human olfactory bulb-derived neural stem cells (OBNSCs), to define a gene expression pattern and signaling pathways that are specific for each cell lineage. We have demonstrated large differences in the gene expression profile of human embryonic NSC, and adult human OBNSCs, but less variability between parallel cultures. Transcripts of genes involved in neural tube development and patterning (ALDH1A2, FOXA2), progenitor marker genes (LMX1a, ALDH1A1, SOX10), proliferation of neural progenitors (WNT1 and WNT3a), neuroplastin (NPTN), POU3F1 (OCT6), neuroligin (NLGN4X), MEIS2, and NPAS1 were up-regulated in both cell populations. By Gene Ontology, 325 out of 3875 investigated gene sets were scientifically different. 41 out of the 307 investigated Cellular Component (CC) categories, 45 out of the 620 investigated Molecular Function (MF) categories, and 239 out of the 2948 investigated Biological Process (BP) categories were significant. KEGG Pathway Class Comparison had revealed that 75 out of 171 investigated gene sets passed the 0.005 significance threshold. Levels of gene expression were explored in three signaling pathways, Notch, Wnt, and mTOR that are known to be involved in NS cell fates determination. The transcriptional signature also deciphers the role of genes involved in epigenetic modifications. SWI/SNF DNA chromatin remodeling complex family, including SMARCC1 and SMARCE1, were found specifically up-regulated in our OBNSC but not in hENSC. Differences in gene expression profile of transcripts controlling epigenetic modifications, and signaling pathways might indicate differences in the therapeutic potential of our examined two cell populations in relation to in cell survival, proliferation, migration, and differentiation following engraftments in different CNS insults. PMID:22485144

  12. Nationwide survey of BK polyomavirus associated hemorrhagic cystitis in adult allogeneic stem cell transplantation among haematologists and urologists.

    PubMed

    Schneidewind, Laila; Neumann, Thomas; Kranz, Jennifer; Knoll, Florian; Pelzer, Alexandre Egon; Schmidt, Christian; Krüger, William

    2017-02-03

    There are no epidemiological data on BK virus associated hemorrhagic cystitis (BKHC) in adult allogeneic stem cell transplantation in Germany available and associations with clinical conditions like GvHD are controversially discussed. Therefore, we conducted a nationwide survey among haematologists and urologists about this disease. We developed two questionnaires, one for haematologists (26 items) and one for urologists (20 items) concerning BKHC in adult allogeneic stem cell transplantation with epidemiological data and clinical implications. The survey was sent out at least three times to EBMT registered centres performing at least five transplantations a year, leading to 39 centres. The recruiting time was between January and June 2016. Total response rates were 76.9% among haematologists and 74.4% among urologists. BKHC seems to appear less frequent in this survey than it is described in the literature. Six deaths in the last 5 years due to this disease have been reported. Interestingly, haematologists as well as urologists mostly think that local therapy is most effective while 50.0% stated that there is no real effective oral or intravenous medication. Associations with other clinical conditions mentioned were heterogeneous, e.g. transplantation type, CMV reactivation, acute GvHD, nephropathy and worse clinical outcome. There was a significant discrepancy between haematologists and urologist concerning the association with acute GvHD (p = 0.004). We need prospective, multicentric clinical studies to evaluate local therapy and for developing a risk stratification model since this disease can be severe with morbidity and rarely mortality. In our opinion, this should be an interdisciplinary approach.

  13. Transplantation of cultured autologous melanocytes: hope or danger?

    PubMed

    Czajkowski, Rafal; Pokrywczynska, Marta; Placek, Waldemar; Zegarska, Barbara; Tadrowski, Tadeusz; Drewa, Tomasz

    2010-01-01

    Cultured human melanocytes are increasingly being used in the treatment of vitiligo. The growth media contain various types of mitogenic factors, both recombinant human (e.g., rhbFGF and rhSCF) and synthetic (e.g., TPA). High concentrations of mitogenic factors accelerate the cell cycle, and consequently may increase the risk of carcinogenesis of transplanted cells. Mutations of genes of the RAS/RAF/MEK/ERK signaling pathway are very often found in the early stages of the development of melanoma. TPA is considered to be an oncogenic factor, but so far there is no evidence to show that it is responsible for damage to the genetic material of cultured melanocytes. The aim of our study was to assess the risk of the development of mutations in selected genes of the RAS/RAF/MEK/ERK signaling pathway during the culturing of melanocytes in various growth media. Based on the results obtained, it can be concluded that TPA and high concentrations of other growth factors intensify the proliferation of melanocytes, without the risk of damage to the HRAS (exon 1 and 2), KRAS (exon 1 and 2), NRAS (exon 1 and 2), and BRAF (exon 11 and 15) genes. In order to assess the total safety of the transplantation of cultured melanocytes, it is necessary to carry out further studies on other signaling pathways as well as carry out biological tests on an animal model.

  14. Effect of streptomycin on melanogenesis and antioxidant status in melanocytes.

    PubMed

    Wrześniok, Dorota; Beberok, Artur; Otręba, Michał; Buszman, Ewa

    2013-11-01

    Streptomycin is an aminoglycoside antibiotic with an antituberculosis activity commonly used in clinical practice due to its good antimicrobial characteristics. A well-known undesirable side effect of this drug is ototoxicity, which may be caused by overproduction of reactive oxygen species and loss of melanocytes in the inner ear. The aim of this study was to examine the effect of streptomycin on melanogenesis and antioxidant defense system in cultured normal human melanocytes (HEMa-LP). Streptomycin induced concentration-dependent loss in melanocytes viability. The value of EC50 was determined to be ~5.0 mM. It has been shown that streptomycin causes inhibition of tyrosinase activity and reduces melanin content in human melanocytes in a concentration-dependent manner. Significant changes in the activity of cellular antioxidant enzymes: superoxide dismutase, catalase, and glutathione peroxidase were also stated. The results obtained in vitro may explain a potential role of melanocytes and melanin in the causative mechanisms of aminoglycosides ototoxic effects in vivo.

  15. Melanin: the biophysiology of oral melanocytes and physiological oral pigmentation.

    PubMed

    Feller, Liviu; Masilana, Aubrey; Khammissa, Razia A G; Altini, Mario; Jadwat, Yusuf; Lemmer, Johan

    2014-03-24

    The presence of melanocytes in the oral epithelium is a well-established fact, but their physiological functions are not well defined. Melanin provides protection from environmental stressors such as ultraviolet radiation and reactive oxygen species; and melanocytes function as stress-sensors having the capacity both to react to and to produce a variety of microenvironmental cytokines and growth factors, modulating immune, inflammatory and antibacterial responses. Melanocytes also act as neuroendocrine cells producing local neurotransmitters including acetylcholine, catecholamines and opioids, and hormones of the melanocortin system such as proopiomelanocortin, adrenocorticotropic hormone and α-melanocyte stimulating hormone, that participate in intracellular and in intercellular signalling pathways, thus contributing to tissue homeostasis.There is a wide range of normal variation in melanin pigmentation of the oral mucosa. In general, darker skinned persons more frequently have oral melanin pigmentation than light-skinned persons. Variations in oral physiological pigmentation are genetically determined unless associated with some underlying disease.In this article, we discuss some aspects of the biophysiology of oral melanocytes, of the functions of melanin, and of physiological oral pigmentation.

  16. Beta Cell Regeneration in Adult Mice: Controversy Over the Involvement of Stem Cells.

    PubMed

    Yu, Ke; Fischbach, Shane; Xiao, Xiangwei

    2016-01-01

    Islet transplantation is an effective therapy for severe diabetes. Nevertheless, the short supply of donor pancreases constitutes a formidable obstacle to its extensive clinical application. This shortage heightens the need for alternative sources of insulin-producing beta cells. Since mature beta cells have a very slow proliferation rate, which further declines with age, great efforts have been made to identify beta cell progenitors in the adult pancreas. However, the question whether facultative beta cell progenitors indeed exist in the adult pancreas remains largely unresolved. In the current review, we discuss the problems in past studies and review the milestone studies and recent publications.

  17. Beta Cell Regeneration in Adult Mice: Controversy Over the Involvement of Stem Cells

    PubMed Central

    Yu, Ke; Fischbach, Shane; Xiao, Xiangwei

    2016-01-01

    Islet transplantation is an effective therapy for severe diabetes. Nevertheless, the short supply of donor pancreases constitutes a formidable obstacle to its extensive clinical application. This shortage heightens the need for alternative sources of insulin-producing beta cells. Since mature beta cells have a very slow proliferation rate, which further declines with age, great efforts have been made to identify beta cell progenitors in the adult pancreas. However, the question whether facultative beta cell progenitors indeed exist in the adult pancreas remains largely unresolved. In the current review, we discuss the problems in past studies and review the milestone studies and recent publications. PMID:25429702

  18. A discussion on adult mesenchymal stem cells for drug delivery: pros and cons.

    PubMed

    Sherman, Lauren S; Condé-Green, Alexandra; Sandiford, Oleta A; Rameshwar, Pranela

    2015-01-01

    Mesenchymal stem cells (MSCs) are emerging as candidates for drug delivery to treat numerous diseases. Their ease of isolation, expansion and reduced ethical concern, coupled with their 'plastic' immune functions and homing abilities make MSCs an appealing choice as cellular vehicle for drug delivery, including the delivery of RNA. However, while MSCs are currently listed for thousands of clinical trials, there are many confounding factors that have yet to be elucidated. In this review, we address many of the benefits of MSCs as therapeutic agents, and discuss confounding factors that require further scientific exploration.

  19. Culturing adult human bone marrow stem cells on gelatin scaffold with pNIPAAm as transplanted grafts for skin regeneration.

    PubMed

    Perng, Cherng-Kang; Kao, Chung-Lan; Yang, Yi-Ping; Lin, Han-Tso; Lin, Wen-Bin; Chu, Yue-Ru; Wang, Hsiao-Jung; Ma, Hsu; Ku, Hung-Hai; Chiou, Shih-Hwa

    2008-03-01

    Skin tissue engineering is a possible solution for the treatment of extensive skin defect. The ultimate goal of skin tissue engineering is to restore the complete functions of native skin, but until now the structures and functions of skins are only partially restored. By negative immunoselection (CD45 and glycophorin A), we isolated and cultivated adult human bone marrow stem cells (hBMSCs) that are of multilineage differentiation potential. In this study, we first demonstrated that by using gelatin/thermo-sensitive poly N-isopropylacrylamide (pNIPAAm) and the immunocompromised mice model, the hBMSCs possess the differentiation potential of epidermis and the capability of healing skin wounds. The in vitro observations and the results of the scanning electron microscope showed that the hBMSCs can attach and proliferate in the gelatin/thermo-sensitive pNIPAAm. To further monitor the in vivo growth effect of the hBMSCs in the skin-defected nude mice, the green fluorescence protein (GFP) gene was transduced into the hBMSCs by the murine stem cell viral vector. The results showed that the rates of cell growth and wound recovery in the hBMSC-treated group were significantly higher than those in the control group, which was only treated with the gelatin/pNIPAAm (p < 0.01). More importantly, the re-epithelialization markers of human pan-cytokeratin and E-cadherin were significantly increased on day 7, day 14, and day 21 after the hBMSC-scaffold with the pNIPAAM in the mice with skin defects (p < 0.05). Moreover, the stem cell markers of human CD13 and CD105 were gradually decreased during the period of wound healing. In sum, this novel method provides a transferring system for cell therapies and maintains its temperature-sensitive property of easy-peeling by lower-temperature treatment. In addition, the in vitro and in vivo GFP imaging systems provide a new imaging modality for understanding the differentiation process and the effective expression of stem cells in wound

  20. Methylene Blue (Tetramethylthionine Chloride) Influences the Mobility of Adult Neural Stem Cells: A Potentially Novel Therapeutic Mechanism of a Therapeutic Approach in the Treatment of Alzheimer's Disease.

    PubMed

    van der Ven, Amelie T; Pape, Julius C; Hermann, Dirk; Schloesser, Robert; Genius, Just; Fischer, Nadine; Mößner, Rainald; Scherbaum, Norbert; Wiltfang, Jens; Rujescu, Dan; Benninghoff, Jens

    2017-01-01

    An interest in neurogenesis in the adult human brain as a relevant and targetable process has emerged as a potential treatment option for Alzheimer's disease and other neurodegenerative conditions. The aim of this study was to investigate the effects of tetramethylthionine chloride (methylene blue, MB) on properties of adult murine neural stem cells. Based on recent clinical studies, MB has increasingly been discussed as a potential treatment for Alzheimer's disease. While no differences in the proliferative capacity were identified, a general potential of MB in modulating the migratory capacity of adult neural stem cells was indicated in a cell mobility assay. To our knowledge, this is the first time that MB could be associated with neural mobility. The results of this study add insight to the spectrum of features of MB within the central nervous system and may be helpful for understanding the molecular mechanisms underlying a potential therapeutic effect of MB.

  1. Induction of nerve growth factor receptors on cultured human melanocytes

    SciTech Connect

    Peacocke, M.; Yaar, M.; Mansur, C.P.; Chao, M.V.; Gilchrest, B.A. )

    1988-07-01

    Normal differentiation and malignant transformation of human melanocytes involve a complex series of interactions during which both genetic and environmental factors play roles. At present, the regulation of these processes is poorly understood. The authors have induced the expression of nerve growth factor (NGF) receptors on cultured human melanocytes with phorbol 12-tetradecanoate 13-acetate and have correlated this event with the appearance of a more differentiated, dendritic morphology. Criteria for NGF receptor expression included protein accumulation and cell-surface immunofluorescent staining with a monoclonal antibody directed against the human receptor and induction of the messenger RNA species as determined by blot-hybridization studies. The presence of the receptor could also be induced by UV irradiation or growth factor deprivation. The NGF receptor is inducible in cultured human melanocytes, and they suggest that NGF may modulate the behavior of this neural crest-derived cell in the skin.

  2. Metaplastic breast carcinoma; melanocytic variant, a very rare tumour

    PubMed Central

    Nzegwu, Martin A.; Sule, Emmanuel; Uzoigwe, Joseph; Achi, Franklyn

    2015-01-01

    Metaplastic breast carcinoma (MBC) is a rare heterogeneous malignancy, accounting for <1% of all invasive breast carcinomas, in which adenocarcinoma is found to coexist with an admixture of spindle, squamous, chondroid or bone-forming neoplastic cells. Melanocytic variant was first described by Ruffolo et al. in 1997. We report a case of MBC, melanocytic variant, in a 57-year-old Nigerian female who presented with a left breast mass 8 cm in diameter in the upper outer quadrant, hard and gradually increase in size to become painful. Breast examination showed gross asymmetry. Left breast was oedematous and shiny with extensive peau d'orange. No palpable axillary nodes were seen. Chest X-ray and abdominal ultrasound scan showed no involvement. Breast biopsy revealed an invasive metaplastic ductal carcinoma with melanocytic differentiation. PMID:25666364

  3. Pediatric and Adult High-Grade Glioma Stem Cell Culture Models Are Permissive to Lytic Infection with Parvovirus H-1

    PubMed Central

    Josupeit, Rafael; Bender, Sebastian; Kern, Sonja; Leuchs, Barbara; Hielscher, Thomas; Herold-Mende, Christel; Schlehofer, Jörg R.; Dinsart, Christiane; Witt, Olaf; Rommelaere, Jean; Lacroix, Jeannine

    2016-01-01

    Combining virus-induced cytotoxic and immunotherapeutic effects, oncolytic virotherapy represents a promising therapeutic approach for high-grade glioma (HGG). A clinical trial has recently provided evidence for the clinical safety of the oncolytic parvovirus H-1 (H-1PV) in adult glioblastoma relapse patients. The present study assesses the efficacy of H-1PV in eliminating HGG initiating cells. H-1PV was able to enter and to transduce all HGG neurosphere culture models (n = 6), including cultures derived from adult glioblastoma, pediatric glioblastoma, and diffuse intrinsic pontine glioma. Cytotoxic effects induced by the virus have been observed in all HGG neurospheres at half maximal inhibitory concentration (IC50) doses of input virus between 1 and 10 plaque forming units per cell. H-1PV infection at this dose range was able to prevent tumorigenicity of NCH421k glioblastoma multiforme (GBM) “stem-like” cells in NOD/SCID mice. Interestingly NCH421R, an isogenic subclone with equal capacity of xenograft formation, but resistant to H-1PV infection could be isolated from the parental NCH421k culture. To reveal changes in gene expression associated with H-1PV resistance we performed a comparative gene expression analysis in these subclones. Several dysregulated genes encoding receptor proteins, endocytosis factors or regulators innate antiviral responses were identified and represent intriguing candidates for to further study molecular mechanisms of H-1PV resistance. PMID:27213425

  4. Cell-permeable p38 MAP kinase promotes migration of adult neural stem/progenitor cells

    PubMed Central

    Hamanoue, Makoto; Morioka, Kazuhito; Ohsawa, Ikuroh; Ohsawa, Keiko; Kobayashi, Masaaki; Tsuburaya, Kayo; Akasaka, Yoshikiyo; Mikami, Tetsuo; Ogata, Toru; Takamatsu, Ken

    2016-01-01

    Endogenous neural stem/progenitor cells (NPCs) can migrate toward sites of injury, but the migration activity of NPCs is insufficient to regenerate damaged brain tissue. In this study, we showed that p38 MAP kinase (p38) is expressed in doublecortin-positive adult NPCs. Experiments using the p38 inhibitor SB203580 revealed that endogenous p38 participates in NPC migration. To enhance NPC migration, we generated a cell-permeable wild-type p38 protein (PTD-p38WT) in which the HIV protein transduction domain (PTD) was fused to the N-terminus of p38. Treatment with PTD-p38WT significantly promoted the random migration of adult NPCs without affecting cell survival or differentiation; this effect depended on the cell permeability and kinase activity of the fusion protein. These findings indicate that PTD-p38WT is a novel and useful tool for unraveling the roles of p38, and that this protein provides a reasonable approach for regenerating the injured brain by enhancing NPC migration. PMID:27067799

  5. Mathematical modelling of adult hippocampal neurogenesis: effects of altered stem cell dynamics on cell counts and bromodeoxyuridine-labelled cells

    PubMed Central

    Ziebell, Frederik; Martin-Villalba, Ana; Marciniak-Czochra, Anna

    2014-01-01

    In the adult hippocampus, neurogenesis—the process of generating mature granule cells from adult neural stem cells—occurs throughout the entire lifetime. In order to investigate the involved regulatory mechanisms, knockout (KO) experiments, which modify the dynamic behaviour of this process, were conducted in the past. Evaluating these KOs is a non-trivial task owing to the complicated nature of the hippocampal neurogenic niche. In this study, we model neurogenesis as a multicompartmental system of ordinary differential equations based on experimental data. To analyse the results of KO experiments, we investigate how changes of cell properties, reflected by model parameters, influence the dynamics of cell counts and of the experimentally observed counts of cells labelled by the cell division marker bromodeoxyuridine (BrdU). We find that changing cell proliferation rates or the fraction of self-renewal, reflecting the balance between symmetric and asymmetric cell divisions, may result in multiple time phases in the response of the system, such as an initial increase in cell counts followed by a decrease. Furthermore, these phases may be qualitatively different in cells at different differentiation stages and even between mitotically labelled cells and all cells existing in the system. PMID:24598209

  6. Photoreceptor precursors derived from three-dimensional embryonic stem cell cultures integrate and mature within adult degenerate retina.

    PubMed

    Gonzalez-Cordero, Anai; West, Emma L; Pearson, Rachael A; Duran, Yanai; Carvalho, Livia S; Chu, Colin J; Naeem, Arifa; Blackford, Samuel J I; Georgiadis, Anastasios; Lakowski, Jorn; Hubank, Mike; Smith, Alexander J; Bainbridge, James W B; Sowden, Jane C; Ali, Robin R

    2013-08-01

    Irreversible blindness caused by loss of photoreceptors may be amenable to cell therapy. We previously demonstrated retinal repair and restoration of vision through transplantation of photoreceptor precursors obtained from postnatal retinas into visually impaired adult mice. Considerable progress has been made in differentiating embryonic stem cells (ESCs) in vitro toward photoreceptor lineages. However, the capability of ESC-derived photoreceptors to integrate after transplantation has not been demonstrated unequivocally. Here, to isolate photoreceptor precursors fit for transplantation, we adapted a recently reported three-dimensional (3D) differentiation protocol that generates neuroretina from mouse ESCs. We show that rod precursors derived by this protocol and selected via a GFP reporter under the control of a Rhodopsin promoter integrate within degenerate retinas of adult mice and mature into outer segment-bearing photoreceptors. Notably, ESC-derived precursors at a developmental stage similar to postnatal days 4-8 integrate more efficiently compared with cells at other stages. This study shows conclusively that ESCs can provide a source of photoreceptors for retinal cell transplantation.

  7. Transplantation of Adult Monkey Neural Stem Cells into A Contusion Spinal Cord Injury Model in Rhesus Macaque Monkeys

    PubMed Central

    Hajinasrollah, Mostafa; Zare Mehrjerdi, Nargess; Azizi, Hossein; Hemmesi, Katayoun; Moghiminasr, Reza; Azhdari, Zahra; Talebi, Ardeshir; Mohitmafi, Soroush; Vosough Taqi Dizaj, Ahmad; Sharifi, Giuve; Baharvand, Hossein; Rezaee, Omidvar; Kiani, Sahar

    2014-01-01

    Objective Currently, cellular transplantation for spinal cord injuries (SCI) is the subject of numerous preclinical studies. Among the many cell types in the adult brain, there is a unique subpopulation of neural stem cells (NSC) that can self-renew and differentiate into neurons. The study aims, therefore, to explore the efficacy of adult monkey NSC (mNSC) in a primate SCI model. Materials and Methods In this experimental study, isolated mNSCs were analyzed by flow cytometry, immunocytochemistry, and RT-PCR. Next, BrdU-labeled cells were transplanted into a SCI model. The SCI animal model was confirmed by magnetic resonance imaging (MRI) and histological analysis. Animals were clinically observed for 6 months. Results Analysis confirmed homing of mNSCs into the injury site. Transplanted cells expressed neuronal markers (TubIII). Hind limb performance improved in trans- planted animals based on Tarlov’s scale and our established behavioral tests for monkeys. Conclusion Our findings have indicated that mNSCs can facilitate recovery in contusion SCI models in rhesus macaque monkeys. Additional studies are necessary to determine the im- provement mechanisms after cell transplantation. PMID:24567941

  8. Pediatric and Adult High-Grade Glioma Stem Cell Culture Models Are Permissive to Lytic Infection with Parvovirus H-1.

    PubMed

    Josupeit, Rafael; Bender, Sebastian; Kern, Sonja; Leuchs, Barbara; Hielscher, Thomas; Herold-Mende, Christel; Schlehofer, Jörg R; Dinsart, Christiane; Witt, Olaf; Rommelaere, Jean; Lacroix, Jeannine

    2016-05-19

    Combining virus-induced cytotoxic and immunotherapeutic effects, oncolytic virotherapy represents a promising therapeutic approach for high-grade glioma (HGG). A clinical trial has recently provided evidence for the clinical safety of the oncolytic parvovirus H-1 (H-1PV) in adult glioblastoma relapse patients. The present study assesses the efficacy of H-1PV in eliminating HGG initiating cells. H-1PV was able to enter and to transduce all HGG neurosphere culture models (n = 6), including cultures derived from adult glioblastoma, pediatric glioblastoma, and diffuse intrinsic pontine glioma. Cytotoxic effects induced by the virus have been observed in all HGG neurospheres at half maximal inhibitory concentration (IC50) doses of input virus between 1 and 10 plaque forming units per cell. H-1PV infection at this dose range was able to prevent tumorigenicity of NCH421k glioblastoma multiforme (GBM) "stem-like" cells in NOD/SCID mice. Interestingly NCH421R, an isogenic subclone with equal capacity of xenograft formation, but resistant to H-1PV infection could be isolated from the parental NCH421k culture. To reveal changes in gene expression associated with H-1PV resistance we performed a comparative gene expression analysis in these subclones. Several dysregulated genes encoding receptor proteins, endocytosis factors or regulators innate antiviral responses were identified and represent intriguing candidates for to further study molecular mechanisms of H-1PV resistance.

  9. Adult stem cells and mammalian epimorphic regeneration-insights from studying annual renewal of deer antlers.