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Sample records for spindle cell differentiation

  1. Pituitary spindle cell oncocytoma

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    Soledad Sosa

    2018-01-01

    Full Text Available Spindle cell oncocytoma is an infrequent benign non-endocrine sellar neoplasm. Due to its similar morphology to pituitary adenomas, consideration of this differential diagnosis would conduce to a more careful surgical approach in order to avoid intraoperative bleeding and aiming to a complete resection, on which depends long-term outcomes. We present the case of a 60-year-old male who complained about visual abnormalities, with computerized visual field confirmation. On biochemistry, a panhypopituitarism was detected. The brain magnetic resonance images showed a sellar mass. A non-functioning pituitary macroadenoma was presumptively diagnosed and due to the visual impairment, surgical transesphenoidal treatment was indicated. The histological diagnosis was spindle cell oncocytoma. Five months after surgery, the control image demonstrated a lesion that was considered as remnant tumor, hence radiosurgery was performed. During the follow-up, the tumor reduced its size and four years after initial treatment, the sellar resonance imaging showed disappearance of the residual tumor. Communication of new cases of this rare entity will enlarge the existing evidence and will help to determinate the most effective treatment and prognosis.

  2. Spindle cell oncocytoma of adenohypophysis: Cytogenetics and β-catenin findings with pathology differential diagnosis and review of the literature

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    Jianwu Xie

    2017-09-01

    Full Text Available Spindle cell oncocytoma (SCO is an extremely rare neoplasm arising in the anterior pituitary. We report comprehensive pathological description of a case of SCO in a 60 year-old male who presented with nausea, vomiting and severe hyponatremia, and pan hypopituitarism. Magnetic resonance imaging (MRI showed a 3.1 × 2.3 × 2.0 cm homogeneously enhancing bilobed mass within the sella turcica and suprasellar cistern. Intraoperative frozen section and touch imprint cytology showed cohesive spindle cells with abundant oncocytic cytoplasm. Histologic sections revealed the tumor was composed of interlacing fascicles of compact spindled cells with abundant dense oncocytic cytoplasm. There was no mitosis or necrosis present. Ki-67 index varied in areas, with an average of 3%. By immunohistochemistry (IHC, the tumor cells were negative for Cam5.2, AE1/3, neurofilament (NF, NeuN, glial fibrillary acidic protein (GFAP and synaptophysin, and strongly positive for vimentin, TTF-1 and EMA. S-100 showed focal weakly positivity. By electron microscopy (EM, the cytoplasm of the spindle cells contained numerous abundant, back-to-back, uniform, round, normal-sized mitochondria with long and lamellar cristae. Beta-catenin showed diffuse membranous and partial cytoplasmic positivity. Cytogenetic analysis showed extra copies of chromosome 1 (74%, up to 8 copies, and loss of chromosome 2 (35%. The histogenesis, classification and differential diagnosis are discussed.

  3. Spindle Cell Metaplastic Breast Cancer: Case Report

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    Dursun Ozgur Karakas

    2013-08-01

    Conclusion: Spindle cell metaplastic breast cancer must be considered in differential diagnosis of breast cancers, and preoperative immunohistochemical examination, including cytokeratin and vimentin, must be added to pathological examination in intervening cases. [Arch Clin Exp Surg 2013; 2(4.000: 259-262

  4. Breast spindle cell tumours: about eight cases

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    Abd El All Howayda S

    2006-07-01

    Full Text Available Abstract Background Breast spindle cell tumours (BSCTs, although rare, represent a heterogeneous group with different treatment modalities. This work was undertaken to evaluate the utility of fine needle aspiration cytology (FNAC, histopathology and immunohistochemistry (IHC in differentiating BSCTs. Methods FNAC of eight breast masses diagnosed cytologically as BSCTs was followed by wide excision biopsy. IHC using a panel of antibodies against vimentin, pan-cytokeratin, s100, desmin, smooth muscle actin, CD34, and CD10 was evaluated to define their nature. Results FNAC defined the tumors as benign (n = 4, suspicious (n = 2 and malignant (n = 3, based on the cytopathological criteria of malignancy. Following wide excision biopsy, the tumors were reclassified into benign (n = 5 and malignant (n = 3. In the benign group, the diagnosis was raised histologically and confirmed by IHC for 3 cases (one spindle cell lipoma, one myofibroblastoma and one leiomyoma. For the remaining two cases, the diagnosis was set up after IHC (one fibromatosis and one spindle cell variant of adenomyoepithelioma. In the malignant group, a leiomyosarcoma was diagnosed histologically, while IHC was crucial to set up the diagnosis of one case of spindle cell carcinoma and one malignant myoepithelioma. Conclusion FNAC in BSCTs is an insufficient tool and should be followed by wide excision biopsy. The latter technique differentiate benign from malignant BSCTs and is able in 50% of the cases to set up the definite diagnosis. IHC is of value to define the nature of different benign lesions and is mandatory in the malignant ones for optimal treatment. Awareness of the different types of BSCTs prevents unnecessary extensive therapeutic regimes.

  5. The Spindle Cell Neoplasms of the Oral Cavity.

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    Shamim, Thorakkal

    2015-01-01

    Spindle cell neoplasms are defined as neoplasms that consist of spindle-shaped cells in the histopathology. Spindle cell neoplasms can affect the oral cavity. In the oral cavity, the origin of the spindle cell neoplasms may be traced to epithelial, mesenchymal and odontogenic components. This article aims to review the spindle cell neoplasms of the oral cavity with emphasis on histopathology.

  6. Spinal spindle cell haemangioma: an atypical location.

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    Talan-Hranilović, J; Vucić, M; Sajko, T; Bedek, D; Tomić, K; Lupret, V

    2007-03-01

    We present a case of the 31-year-old male patient who complained of weakness in both legs and progressed slowly. Neuroimagine of the thoracic spine showed an intraspinal, extradural mass lesion, measuring 5.3 x 1.2 cm at the Th1-Th3 level. Histologically the lesion was a spindle cell haemangioma composed of dilated vascular spaces and a proliferation of bland appearing interspersed spindle cells. Immunohistochemical analysis was diffusely positive for VIM, SMA and focally for CD34. This lesion is uncommon and shows a predilection for distal extremities. Spindle cell haemangioma within the spine has not been previously reported in the literature.

  7. The relationship between cell killing, chromosome aberrations, spindle defects, and mitotic delay in mouse lymphoma cells of differential sensitivity to X-rays

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    Scott, D.; Zampetti-Bosseler, F.

    1980-01-01

    A study has been made of the effects of x radiation on an ultrasensitive subline of L5178Y mouse lymphoma cells. It has been shown that at survival levels above about 20 per cent, chromosome structural aberrations which lead to bridges and fragments at anaphase are about four times more frequent than spindle defects. The results demonstrated the higher frequency of structural aberrations and spindle defects, and the greater mitotic delay in the X-ray-sensitive than in the X-ray-resistant cell line. A model is proposed which causally relates these end-points to cell killing and DNA repair. (author)

  8. Unusual recurrent tongue spindle cell carcinoma with marked anaplasia occurring at the site of glossectomy for a well-differentiated squamous cell carcinoma: A case report.

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    Okuyama, Kohei; Fujita, Shuichi; Yanamoto, Souichi; Naruse, Tomofumi; Sakamoto, Yuki; Kawakita, Akiko; Omori, Keisuke; Tsuchihashi, Hiroki; Umeda, Masahiro

    2017-09-01

    Spindle cell carcinoma (SpCC), which predominantly arises in the oral, pharyngeal and laryngeal mucosal tissues, is composed of a mixture of squamous and sarcomatoid components. The present study describes the case of a 62-year-old woman with SpCC recurrence 4 years after an initial surgery to remove a well-differentiated primary squamous cell carcinoma (SCC) of the tongue. The recurrent tumor was spherical and located deep within the tongue tissue, which differs from the typical manifestation of ulcerated masses of the mucosa. The majority of cases of recurrence involving SpCC are associated with radiotherapeutic treatment of the primary malignancy; however, the patient in the present study had not received postoperative radiotherapy for SCC. Furthermore, the recurrent tumor in the present case exhibited marked anaplasia and sarcomatoid features, and the absence of SCC elements upon biopsy rendered histological diagnosis difficult. In summary, the present findings suggest that immunohistochemical examination and identification of SCC components are essential for ensuring the accuracy of the histological diagnosis of recurrent SpCC following a primary epithelial malignancy.

  9. Spindle Cell Carcinoma of the hypopharynx: a case report

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    Dillu Ram Kandel

    2018-03-01

    Full Text Available Spindle cell carcinoma of hpopharynx is a rare pathology. It is a poorly differentiated variant of squamous cell carcinoma and morphologically resembles sarcoma. This is a disease of old age. It is usually associated with smoking and alcohol abuse. When it is associated with radiation exposure history it behaves more aggressively. Surgery is considered as the main modality of treatment and adjuvant radiotherapy if necessary. Here we present a case of 79 year old male with spindle cell carcinomaof right piriform fossa with 2-month history of progressive dysphasia and hoarseness that has been affecting his ability to speak and swallow with history of weight loss and past history of radiotherapy. So possibility of spindle cell carcinoma of the hypopharynx should beconsidered in an old patient with rapidly developing swelling of the hypopharynx with past history of radiation exposure. As it is a highly aggressive disease it should be treated timely and more aggressively to prolong the survival of the patient.   

  10. Mitotic spindle proteomics in Chinese hamster ovary cells.

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    Mary Kate Bonner

    Full Text Available Mitosis is a fundamental process in the development of all organisms. The mitotic spindle guides the cell through mitosis as it mediates the segregation of chromosomes, the orientation of the cleavage furrow, and the progression of cell division. Birth defects and tissue-specific cancers often result from abnormalities in mitotic events. Here, we report a proteomic study of the mitotic spindle from Chinese Hamster Ovary (CHO cells. Four different isolations of metaphase spindles were subjected to Multi-dimensional Protein Identification Technology (MudPIT analysis and tandem mass spectrometry. We identified 1155 proteins and used Gene Ontology (GO analysis to categorize proteins into cellular component groups. We then compared our data to the previously published CHO midbody proteome and identified proteins that are unique to the CHO spindle. Our data represent the first mitotic spindle proteome in CHO cells, which augments the list of mitotic spindle components from mammalian cells.

  11. Spindle epithelial tumor with thymus-like differentiation of thyroid gland: Report of two cases with follow-up

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    Nisa Azizun

    2010-10-01

    Full Text Available Spindle epithelial tumor with thymus-like differentiation (SETTLE is a rare malignant thyroid tumor showing thymic or related branchial pouch differentiation. The tumors are composed predominantly of spindle cells along with focal epithelial component and ductular formations. SETTLE occurs in young patients, with indolent growth and a tendency to develop delayed blood-borne metastases. We herein report two cases of SETTLE with a follow-up period of 64 months and 30 months, respectively.

  12. TFG-MET fusion in an infantile spindle cell sarcoma with neural features

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    Flucke, U.E.; Noesel, M.M. van; Wijnen, M.; Zhang, L.; Chen, C.L.; Sung, Y.S.; Antonescu, C.R.

    2017-01-01

    An increasing number of congenital and infantile sarcomas displaying a primitive, monomorphic spindle cell phenotype have been characterized to harbor recurrent gene fusions, including infantile fibrosarcoma and congenital spindle cell rhabdomyosarcoma. Here, we report an unusual spindle cell

  13. Regulation of spindle orientation and neural stem cell fate in the Drosophila optic lobe

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    Brand Andrea H

    2007-01-01

    Full Text Available Abstract Background The choice of a stem cell to divide symmetrically or asymmetrically has profound consequences for development and disease. Unregulated symmetric division promotes tumor formation, whereas inappropriate asymmetric division affects organ morphogenesis. Despite its importance, little is known about how spindle positioning is regulated. In some tissues cell fate appears to dictate the type of cell division, whereas in other tissues it is thought that stochastic variation in spindle position dictates subsequent sibling cell fate. Results Here we investigate the relationship between neural progenitor identity and spindle positioning in the Drosophila optic lobe. We use molecular markers and live imaging to show that there are two populations of progenitors in the optic lobe: symmetrically dividing neuroepithelial cells and asymmetrically dividing neuroblasts. We use genetically marked single cell clones to show that neuroepithelial cells give rise to neuroblasts. To determine if a change in spindle orientation can trigger a neuroepithelial to neuroblast transition, we force neuroepithelial cells to divide along their apical/basal axis by misexpressing Inscuteable. We find that this does not induce neuroblasts, nor does it promote premature neuronal differentiation. Conclusion We show that symmetrically dividing neuroepithelial cells give rise to asymmetrically dividing neuroblasts in the optic lobe, and that regulation of spindle orientation and division symmetry is a consequence of cell type specification, rather than a mechanism for generating cell type diversity.

  14. Spindle-cell carcinoma of esophagus: a case report

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    Kim, Ji Chang; Lee, Jae Mun; Jung, Seung Eun; Lee, Kyo Young; Hahn, Seong Tai; Kim, Man Deuk

    2001-01-01

    Spindle-cell carcinoma of the esophagus is a rare malignant tumor composed of both carcinomatous and sarcomatous elements, and has generated many terminology problems. It is characterized by a bulky polypoid intraluminal mass with a lobulated surface located in the middle third of the esophagus. Local expansion of this organ is observed. The lesion may be pedunculated but despite its bulk, causes little obstruction. We report the imaging findings of a case of spindle-cell carcinoma arising in the upper esophagus

  15. MR imaging features of spindle cell lipoma

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    Kirwadi, Anand; Abdul-Halim, Rehan; Highland, Adrian; Kotnis, Nikhil [Sheffield Teaching Hospitals NHS Trust, Radiology Department, Sheffield (United Kingdom); Fernando, Malee [Sheffield Teaching Hospitals NHS Trust, Histopathology Department, Sheffield (United Kingdom)

    2014-02-15

    To assess the MR imaging features of spindle cell lipomas (SCL) and to compare these appearances directly with the histopathological findings. A retrospective review of our soft tissue tumor database was performed. This yielded 1,327 histologically proven lipomas, of which 25 were confirmed as being SCLs. Fourteen of the 25 patients had MR examinations available for review and only these patients were included in our study. Lesions were assessed at MR examination for the degree of internal fat signal content with grade 0 representing 0 % fat signal and grade 4 100 % fat signal. The degree of fat suppression and contrast-enhancement pattern were also recorded. The excision specimens were independently reviewed by a consultant histopathologist. The histology specimens were assessed for the amount of internal fat and non-adipose tissue and graded using the same scale applied for the imaging. Where core needle biopsy (CNB) was performed, the CNB specimens were also examined for positive features of SCL. In our study, 93 % (13/14) of our patients were male and the average age was 58 years. 65 % (9/14) of the lesions presented in the upper back, shoulder, or neck. All lesions were subcutaneous. 35 % (5/14) of the SCLs demonstrated grade 3 (>75 %) or grade 4 (100 %) fat signal on MR examination. 35 % (5/14) of the lesions had grade 2 (25-75 %) fat signal and 29 % (4/14) of the lesions demonstrated grade 0 (0 %) or grade 1 (<25 %) fat signal. 43 % (6/14) of lesions demonstrated homogenous fat suppression, 28 % (4/14) showed focal areas of high internal signal, and 28 % (4/14) had diffuse internal high signal on fluid-sensitive fat-saturated sequences. 86 % (6/7) of the cases demonstrated septal/nodular enhancement. The diagnosis was evident on the CNB specimen in 100 % (9/9) cases. The histopathology fat content grade was in agreement with the imaging grade in 86 % (12/14) cases. The internal signal pattern of SCL can range broadly, with low fat content lesions seen almost

  16. TFG-MET fusion in an infantile spindle cell sarcoma with neural features.

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    Flucke, Uta; van Noesel, Max M; Wijnen, Marc; Zhang, Lei; Chen, Chun-Liang; Sung, Yun-Shao; Antonescu, Cristina R

    2017-09-01

    An increasing number of congenital and infantile sarcomas displaying a primitive, monomorphic spindle cell phenotype have been characterized to harbor recurrent gene fusions, including infantile fibrosarcoma and congenital spindle cell rhabdomyosarcoma. Here, we report an unusual spindle cell sarcoma presenting as a large and infiltrative pelvic soft tissue mass in a 4-month-old girl, which revealed a novel TFG-MET gene fusion by whole transcriptome RNA sequencing. The tumor resembled the morphology of an infantile fibrosarcoma with both fascicular and patternless growth, however, it expressed strong S100 protein immunoreactivity, while lacking SOX10 staining and retaining H3K27me3 expression. Although this immunoprofile suggested partial neural/neuroectodermal differentiation, overall features were unusual and did not fit into any known tumor types (cellular schwannoma, MPNST), raising the possibility of a novel pathologic entity. The TFG-MET gene fusion expands the genetic spectrum implicated in the pathogenesis of congenital spindle cell sarcomas, with yet another example of kinase oncogenic activation through chromosomal translocation. The discovery of this new fusion is significant since the resulting MET activation can potentially be inhibited by targeted therapy, as MET inhibitors are presently available in clinical trials. © 2017 Wiley Periodicals, Inc.

  17. Cytokeratin: a Shortcut to Diagnose Spindle Cell Carcinoma

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    Dehghani Nazhvani A

    2017-09-01

    Full Text Available A relatively rare subtype of squamous cell carcinoma (SCC is spindle cell carcinoma (SPCC. It is composed of epithelium-derived spindle cells arranged in sheets with mesenchymal properties and small, hard-ly detectable regions of SCC, challenging its definite diagnosis. We encountered five cases of SPCC. In case one, chronic inflammation and subepithelial blister with leukoplakia was found 5 years before our examination. And later, exophytic features, keratotic papules and scar with elevated margins was seen on lateral border of the tongue. In case two, three and four, an abnormal soft tissue elevations were examined, and in the fifth case we examined the soft and bony speci-men from the posterior aspect of maxillary ridge. We evaluated all of them histologically and immunohistochemically for cytokeratin to reach final diagnosis.

  18. Radiation-induced spindle cell sarcoma: A rare case report

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    Khan Mubeen

    2009-01-01

    Full Text Available Ionizing radiation has been known to induce malignant transformation in human beings. Radiation-induced sarcomas are a late sequel of radiation therapy. Most sarcomas have been reported to occur after exposure to a radiation dose of 55 Gray (Gy and above, with a dose ranging from 16 to 112 Gys. Spindle cell sarcomas, arising after radiotherapy given to treat the carcinoma of head and neck region is a very uncommon sequel. This is a rare case report of spindle cell sarcoma of left maxilla, in a 24-year-old male, occurring as a late complication of radiotherapy with Cobalt-60 given for the treatment of retinoblastoma of the left eye 21 years back.

  19. Left atrial spindle cell sarcoma – Case report

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    Nihar Mehta

    2012-07-01

    Full Text Available Primary spindle cell sarcoma of the left atrium is an extremely rare tumour. Surgical excision is the mainstay of treatment since it responds poorly to chemotherapy or radiotherapy. In spite of all the treatment, the prognosis remains poor due to inadvertent delay in diagnosis, few therapeutic options and propensity to metastasize. We present a 47-year-old male who underwent a surgical excision of a left atrial mass in February 2010. It was proved to be a high-grade spindle cell sarcoma on histopathology. He presented again in October 2010 with recurrence of the tumour for which he was re-operated. However, the tumour recurred again within one month, to which the patient succumbed.

  20. CD30+ lymphoproliferative disorder with spindle-cell morphology.

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    Martires, Kathryn J; Cohen, Brandon E; Cassarino, David S

    2016-11-01

    Lymphomatoid papulosis (LyP) is classified as a CD30+ primary cutaneous lymphoproliferative disease. The phenotypic variability along the spectrum of CD30+ lymphoproliferative diseases is highlighted by the distinct histologic subtypes of LyP types A, B, C, and the more recently described types D, E, and F. We report the case of an elderly woman with a clinical presentation and histopathologic findings consistent with LyP, whose atypical CD30+ infiltrate uniquely demonstrated a spindle-cell morphology. To our knowledge, this is the first reported case of LyP characterized by CD30+ spindle-shaped cells, and may represent a new and distinct histologic variant of LyP. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  1. Combined classical spindle cell/pleomorphic lipoma spectrum imaging and clinical data

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    Younan, Yara; Gonzalez, Felix; Umpierrez, Monica; Singer, Adam D. [Emory University Hospital, Department of Radiology and Imaging Sciences Section of Musculoskeletal Imaging, Atlanta, GA (United States); Martinez, Anthony; Edgar, Mark [Emory University Hospital, Department of Pathology, Atlanta, GA (United States); Reimer, Nickolas [Emory University Hospital, Department of Orthopedic Surgery, Atlanta, GA (United States); Subhawong, Ty [University of Miami, Department of Radiology, Miami, FL (United States)

    2018-01-15

    Compile the largest study to date on the imaging and clinical features of the classic spindle cell/pleomorphic lipoma spectrum and suggest this diagnosis be included in the differential for benign and malignant macroscopic fat-containing soft tissue masses regardless of the mass location or patient demographics. An institutional search was performed to identify all available classic-type spindle cell/pleomorphic lipomas with available demographic and imaging data. Images and reports were analyzed by one MSK-trained radiologist and radiographic, anatomic and clinical data were recorded. Additionally, a literature search was performed to identify studies describing the spindle cell lipoma spectrum imaging features and were combined with institutional data. Forty-two institutional cases were identified, 37 of which had MRIs performed among which 21 had images available (T1- and T2-weighted pulse sequences) for review while the remainder had outside reports detailing the mass imaging features. There was a mean age of 57 with 79% of cases occurring in males. Contrary to prior reports, 57% of masses were subcutaneous, and the neck and back region accounted for 26% of cases. When the institutional cases were combined with available data in the literature, there was a new sample size of 91 masses, 74 of which had MRI and/or CT data. Eighty-seven percent of masses were heterogeneous, 51% were composed of less than 75% fat, 65% were in the back, neck or shoulder region, 27% of masses were deep and 91% demonstrated enhancement. Eighty-two percent of patients were males with a mean age of 58 at excision. Imaging features, patient demographics and tumor location alone are not enough to differentiate tumors of the spindle cell lipoma spectrum from other macroscopic fat-containing benign and malignant tumors, and these entities should be included in the same imaging differential diagnosis. (orig.)

  2. Fission yeast cells undergo nuclear division in the absence of spindle microtubules.

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    Stefania Castagnetti

    2010-10-01

    Full Text Available Mitosis in eukaryotic cells employs spindle microtubules to drive accurate chromosome segregation at cell division. Cells lacking spindle microtubules arrest in mitosis due to a spindle checkpoint that delays mitotic progression until all chromosomes have achieved stable bipolar attachment to spindle microtubules. In fission yeast, mitosis occurs within an intact nuclear membrane with the mitotic spindle elongating between the spindle pole bodies. We show here that in fission yeast interference with mitotic spindle formation delays mitosis only briefly and cells proceed to an unusual nuclear division process we term nuclear fission, during which cells perform some chromosome segregation and efficiently enter S-phase of the next cell cycle. Nuclear fission is blocked if spindle pole body maturation or sister chromatid separation cannot take place or if actin polymerization is inhibited. We suggest that this process exhibits vestiges of a primitive nuclear division process independent of spindle microtubules, possibly reflecting an evolutionary intermediate state between bacterial and Archeal chromosome segregation where the nucleoid divides without a spindle and a microtubule spindle-based eukaryotic mitosis.

  3. Topological defects in confined populations of spindle-shaped cells

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    Duclos, Guillaume; Erlenkämper, Christoph; Joanny, Jean-François; Silberzan, Pascal

    2017-01-01

    Most spindle-shaped cells (including smooth muscles and sarcomas) organize in vivo into well-aligned `nematic’ domains, creating intrinsic topological defects that may be used to probe the behaviour of these active nematic systems. Active non-cellular nematics have been shown to be dominated by activity, yielding complex chaotic flows. However, the regime in which live spindle-shaped cells operate, and the importance of cell-substrate friction in particular, remains largely unexplored. Using in vitro experiments, we show that these active cellular nematics operate in a regime in which activity is effectively damped by friction, and that the interaction between defects is controlled by the system’s elastic nematic energy. Due to the activity of the cells, these defects behave as self-propelled particles and pairwise annihilate until all displacements freeze as cell crowding increases. When confined in mesoscopic circular domains, the system evolves towards two identical +1/2 disclinations facing each other. The most likely reduced positions of these defects are independent of the size of the disk, the cells’ activity or even the cell type, but are well described by equilibrium liquid crystal theory. These cell-based systems thus operate in a regime more stable than other active nematics, which may be necessary for their biological function.

  4. Live imaging of spindle pole disorganization in docetaxel-treated multicolor cells

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    Sakaushi, Shinji; Nishida, Kumi; Minamikawa, Harumi; Fukada, Takashi; Oka, Shigenori; Sugimoto, Kenji

    2007-01-01

    Treatment of cells with docetaxel at low concentrations induces aberrant bipolar spindles of which two centrosomes stay at only one pole, and also induces multipolar spindles. To gain insight into the relations between centrosome impairment and structural defects of the spindle, live-cell imaging was performed on a human MDA Auro/imp/H3 cell line in which centrosomes/mitotic spindles, nuclear membrane and chromatin were simultaneously visualized by fluorescent proteins. In the presence of docetaxel at IC 50 concentration, the centrosomes did not segregate, and multiple aster-like structures ectopically arose around the disappearing nuclear membrane. Those ectopic structures formed an acentrosomal pole opposing to the two-centrosomes-containing pole. In late metaphase, one pole often fragmented into multiple spindle poles, leading multipolar division. These results suggest that spindle pole fragility may be induced by centrosome impairment, and collapse of the pole may contribute to induction of aneuploid daughter cells

  5. Spindle Cell Carcinoma of Nasal Cavity- A Case Report

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    Mittal, Abhishek; Nagpal, Tapan

    2016-01-01

    Spindle Cell Carcinoma (SpCC), also known as Sarcomatoid Carcinoma, is a rare and peculiar biphasic malignant neoplasm that occurs mainly in the upper aero-digestive tract, mostly in larynx. SCC accounts for 3% of all squamous cell carcinomas (SCCs) in the head and neck region. It is a rare variant of SCC which shows spindled or pleomorphic tumour cells simulating a true sarcoma. We present a case report of SpCC nasal cavity in a 50-year-old female patient, presented with intermittent epistaxis from left nasal cavity. On physical examination, the patient had an ulcero-exophytic type of mass in the left nasal cavity and a smooth bulge on the left side of anterior hard palate. Patient underwent excision of nasal mass along with partial palatectomy by facial degloving approach and reconstruction of palate with naso-labial flap. The postoperative histopathological report showed SCC. Surgery forms the mainstay of treatment. Radiotherapy and Chemotherapy is warranted in order to improve treatment results. As only few cases have been reported, we report a case of this rare entity to contribute for better understanding and awareness of this rare malignancy. PMID:27190843

  6. Dual mechanism controls asymmetric spindle position in ascidian germ cell precursors.

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    Prodon, François; Chenevert, Janet; Hébras, Céline; Dumollard, Rémi; Faure, Emmanuel; Gonzalez-Garcia, Jose; Nishida, Hiroki; Sardet, Christian; McDougall, Alex

    2010-06-01

    Mitotic spindle orientation with respect to cortical polarity cues generates molecularly distinct daughter cells during asymmetric cell division (ACD). However, during ACD it remains unknown how the orientation of the mitotic spindle is regulated by cortical polarity cues until furrowing begins. In ascidians, the cortical centrosome-attracting body (CAB) generates three successive unequal cleavages and the asymmetric segregation of 40 localized postplasmic/PEM RNAs in germ cell precursors from the 8-64 cell stage. By combining fast 4D confocal fluorescence imaging with gene-silencing and classical blastomere isolation experiments, we show that spindle repositioning mechanisms are active from prometaphase until anaphase, when furrowing is initiated in B5.2 cells. We show that the vegetal-most spindle pole/centrosome is attracted towards the CAB during prometaphase, causing the spindle to position asymmetrically near the cortex. Next, during anaphase, the opposite spindle pole/centrosome is attracted towards the border with neighbouring B5.1 blastomeres, causing the spindle to rotate (10 degrees /minute) and migrate (3 microm/minute). Dynamic 4D fluorescence imaging of filamentous actin and plasma membrane shows that precise orientation of the cleavage furrow is determined by this second phase of rotational spindle displacement. Furthermore, in pairs of isolated B5.2 blastomeres, the second phase of rotational spindle displacement was lost. Finally, knockdown of PEM1, a protein localized in the CAB and required for unequal cleavage in B5.2 cells, completely randomizes spindle orientation. Together these data show that two separate mechanisms active during mitosis are responsible for spindle positioning, leading to precise orientation of the cleavage furrow during ACD in the cells that give rise to the germ lineage in ascidians.

  7. Akap350 Recruits Eb1 to The Spindle Poles, Ensuring Proper Spindle Orientation and Lumen Formation in 3d Epithelial Cell Cultures.

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    Almada, Evangelina; Tonucci, Facundo M; Hidalgo, Florencia; Ferretti, Anabela; Ibarra, Solange; Pariani, Alejandro; Vena, Rodrigo; Favre, Cristián; Girardini, Javier; Kierbel, Arlinet; Larocca, M Cecilia

    2017-11-02

    The organization of epithelial cells to form hollow organs with a single lumen requires the accurate three-dimensional arrangement of cell divisions. Mitotic spindle orientation is defined by signaling pathways that provide molecular links between specific spots at the cell cortex and astral microtubules, which have not been fully elucidated. AKAP350 is a centrosomal/Golgi scaffold protein, implicated in the regulation of microtubule dynamics. Using 3D epithelial cell cultures, we found that cells with decreased AKAP350 expression (AKAP350KD) formed polarized cysts with abnormal lumen morphology. Analysis of mitotic cells in AKAP350KD cysts indicated defective spindle alignment. We established that AKAP350 interacts with EB1, a microtubule associated protein that regulates spindle orientation, at the spindle poles. Decrease of AKAP350 expression lead to a significant reduction of EB1 levels at spindle poles and astral microtubules. Conversely, overexpression of EB1 rescued the defective spindle orientation induced by deficient AKAP350 expression. The specific delocalization of the AKAP350/EB1complex from the centrosome decreased EB1 levels at astral microtubules and lead to the formation of 3D-organotypic structures which resembled AKAP350KD cysts. We conclude that AKAP350 recruits EB1 to the spindle poles, ensuring EB1 presence at astral microtubules and proper spindle orientation during epithelial morphogenesis.

  8. Axin localizes to mitotic spindles and centrosomes in mitotic cells

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    Kim, Shi-Mun; Choi, Eun-Jin; Song, Ki-Joon; Kim, Sewoon; Seo, Eunjeong; Jho, Eek-Hoon; Kee, Sun-Ho

    2009-01-01

    Wnt signaling plays critical roles in cell proliferation and carcinogenesis. In addition, numerous recent studies have shown that various Wnt signaling components are involved in mitosis and chromosomal instability. However, the role of Axin, a negative regulator of Wnt signaling, in mitosis has remained unclear. Using monoclonal antibodies against Axin, we found that Axin localizes to the centrosome and along mitotic spindles. This localization was suppressed by siRNA specific for Aurora A kinase and by Aurora kinase inhibitor. Interestingly, Axin over-expression altered the subcellular distribution of Plk1 and of phosphorylated glycogen synthase kinase (GSK3β) without producing any notable changes in cellular phenotype. In the presence of Aurora kinase inhibitor, Axin over-expression induced the formation of cleavage furrow-like structures and of prominent astral microtubules lacking midbody formation in a subset of cells. Our results suggest that Axin modulates distribution of Axin-associated proteins such as Plk1 and GSK3β in an expression level-dependent manner and these interactions affect the mitotic process, including cytokinesis under certain conditions, such as in the presence of Aurora kinase inhibitor

  9. Spindle disturbances in human-hamster hybrid (AL) cells induced by mobile communication frequency range signals.

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    Schrader, Thorsten; Münter, Klaus; Kleine-Ostmann, Thomas; Schmid, Ernst

    2008-12-01

    The production of spindle disturbances in FC2 cells, a human-hamster hybrid (A(L)) cell line, by non-ionizing radiation was studied using an electromagnetic field with a field strength of 90 V/m at a frequency of 835 MHz. Due to the given experimental conditions slide flask cultures were exposed at room temperature in a microTEM (transversal electromagnetic field) cell, which allows optimal experimental conditions for small samples of biological material. Numerical calculations suggest that specific absorption rates of up to 60 mW/kg are reached for maximum field exposure. All exposure field parameters--either measured or calculable--are precisely defined and, for the first time, traceable to the standards of the SI system of physical units. Compared with co-incident negative controls, the results of two independently performed experiments suggest that exposure periods of time from 0.5 to 2 h with an electric field strength of 90 V/m are spindle acting agents as predominately indicated by the appearance of spindle disturbances at the ana- and telophase stages (especially lagging and non-disjunction of single chromosomes) of cell divisions. The spindle disturbances do not change the fraction of mitotic cells with increasing exposure time up to 2 h. Due to the applied experimental conditions an influence of temperature as a confounder parameter for spindle disturbances can be excluded.

  10. TBCD links centriologenesis, spindle microtubule dynamics, and midbody abscission in human cells.

    Directory of Open Access Journals (Sweden)

    Mónica López Fanarraga

    2010-01-01

    Full Text Available Microtubule-organizing centers recruit alpha- and beta-tubulin polypeptides for microtubule nucleation. Tubulin synthesis is complex, requiring five specific cofactors, designated tubulin cofactors (TBCs A-E, which contribute to various aspects of microtubule dynamics in vivo. Here, we show that tubulin cofactor D (TBCD is concentrated at the centrosome and midbody, where it participates in centriologenesis, spindle organization, and cell abscission. TBCD exhibits a cell-cycle-specific pattern, localizing on the daughter centriole at G1 and on procentrioles by S, and disappearing from older centrioles at telophase as the protein is recruited to the midbody. Our data show that TBCD overexpression results in microtubule release from the centrosome and G1 arrest, whereas its depletion produces mitotic aberrations and incomplete microtubule retraction at the midbody during cytokinesis. TBCD is recruited to the centriole replication site at the onset of the centrosome duplication cycle. A role in centriologenesis is further supported in differentiating ciliated cells, where TBCD is organized into "centriolar rosettes". These data suggest that TBCD participates in both canonical and de novo centriolar assembly pathways.

  11. Spindle orientation bias in gut epithelial stem cell compartments is lost in precancerous tissue

    NARCIS (Netherlands)

    Quyn, A.J.; Appleton, P.L.; Carey, F.A.; Steele, R.J.; Barker, N.; Clevers, H.; Ridgway, R.A.; Sansom, O.J.; Nathke, I.S.

    2010-01-01

    The importance of asymmetric divisions for stem cell function and maintenance is well established in the developing nervous system and the skin; however, its role in gut epithelium and its importance for tumorigenesis is still debated. We demonstrate alignment of mitotic spindles perpendicular to

  12. Mammalian neurogenesis requires Treacle-Plk1 for precise control of spindle orientation, mitotic progression, and maintenance of neural progenitor cells.

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    Daisuke Sakai

    Full Text Available The cerebral cortex is a specialized region of the brain that processes cognitive, motor, somatosensory, auditory, and visual functions. Its characteristic architecture and size is dependent upon the number of neurons generated during embryogenesis and has been postulated to be governed by symmetric versus asymmetric cell divisions, which mediate the balance between progenitor cell maintenance and neuron differentiation, respectively. The mechanistic importance of spindle orientation remains controversial, hence there is considerable interest in understanding how neural progenitor cell mitosis is controlled during neurogenesis. We discovered that Treacle, which is encoded by the Tcof1 gene, is a novel centrosome- and kinetochore-associated protein that is critical for spindle fidelity and mitotic progression. Tcof1/Treacle loss-of-function disrupts spindle orientation and cell cycle progression, which perturbs the maintenance, proliferation, and localization of neural progenitors during cortical neurogenesis. Consistent with this, Tcof1(+/- mice exhibit reduced brain size as a consequence of defects in neural progenitor maintenance. We determined that Treacle elicits its effect via a direct interaction with Polo-like kinase1 (Plk1, and furthermore we discovered novel in vivo roles for Plk1 in governing mitotic progression and spindle orientation in the developing mammalian cortex. Increased asymmetric cell division, however, did not promote increased neuronal differentiation. Collectively our research has therefore identified Treacle and Plk1 as novel in vivo regulators of spindle fidelity, mitotic progression, and proliferation in the maintenance and localization of neural progenitor cells. Together, Treacle and Plk1 are critically required for proper cortical neurogenesis, which has important implications in the regulation of mammalian brain size and the pathogenesis of congenital neurodevelopmental disorders such as microcephaly.

  13. Spindle-cell squamous carcinoma of the esophagus: a tumor with biphasic morphology

    International Nuclear Information System (INIS)

    Agha, F.P.; Keren, D.F.

    1985-01-01

    Spindle-cell squamous carcinoma of the esophagus is a rare malignant tumor. It is characterized by a large bulky mass in the middle third of the esophagus with a lobulated surface and local expansion of the esophagus. This lesion may be pedunculated and cause relatively little obstruction despite its bulk. The current view, based on ultrastructure and immunohistochemical evidence, has confirmed that the sarcomatous component of the squamous cell carcinoma originates from mesenchymal metaplasia of squamous cells. On the basis of this evidence and clinical behavior, it seems appropriate to consider carcinosarcoma and pseudosarcoma as equivalents and as variants of squamous cell carcinoma. Four patients with spindle-cell squamous carcinoma, an unusual subset of squamous carcinoma, are described, and the salient radiographic and pathologic features of this disorder's distinctive biphasic morphology are discussed

  14. Expanding the histologic spectrum of mucinous tubular and spindle cell carcinoma of the kidney.

    Science.gov (United States)

    Fine, Samson W; Argani, Pedram; DeMarzo, Angelo M; Delahunt, Brett; Sebo, Thomas J; Reuter, Victor E; Epstein, Jonathan I

    2006-12-01

    Mucinous tubular and spindle cell carcinomas (MTSCs) are polymorphic neoplasms characterized by small, elongated tubules lined by cuboidal cells and/or cords of spindled cells separated by pale mucinous stroma. Nonclassic morphologic variants and features of MTSC have not been well studied. We identified 17 previously unreported MTSCs from Surgical Pathology and consultative files of the authors and their respective institutions and studied their morphologic features. A total of 10/17 cases were considered "classic," as described above, with 5/10 showing at least focal (20% to 50%) tubular predominance without apparent mucinous matrix. Alcian blue staining revealed abundant (>50%) mucin in all classic cases. Seven of 17 MTSCs were classified as "mucin-poor," with little to no extracellular mucin appreciable by hematoxylin and eosin. Four of these cases showed equal tubular and spindled morphology, 2 cases showed spindle cell predominance (70%; 95%), and 1 case showed tubular predominance (90%). In 5/7 mucin-poor cases, staining for Alcian blue revealed scant (<10%) mucin in cellular areas with the other 2 cases having 30% mucin. Unusual histologic features identified in the 17 cases were: foamy macrophages (n=8), papillations/well formed papillae (n=6/n=1), focal clear cells in tubules (n=3), necrosis (n=3), oncocytic tubules (n=2; 40%, 5%), numerous small vacuoles (n=2), heterotopic bone (n=1), psammomatous calcification (n=1), and nodular growth with lymphocytic cuffing (n=1). An exceptional case contained a well-circumscribed, HMB45-positive angiomyolipoma within the MTSC. MTSCs may be "mucin-poor" and show a marked predominance of either of its principal morphologic components, which coupled with the presence of other unusual features such as clear cells, papillations, foamy macrophages, and necrosis, may mimic other forms of renal cell carcinoma. Pathologists must be aware of the spectrum of histologic findings within MTSCs to ensure their accurate diagnosis.

  15. Primary histiocytic sarcoma arising in the head and neck with predominant spindle cell component

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    Zhao XF

    2007-02-01

    Full Text Available Abstract This is the first case report of Histiocytic Sarcoma (HS with predominant spindle cell component occurring in the head and neck region of a 41-year-old man. The tumor was composed of sheets of large round to oval cells with pleomorphic vesicular nuclei, prominent nucleoli and abundant eosinophilic cytoplasm. Multinucleated forms, numerous mitoses, and tumor necrosis were also noted. Sheets, fascicles, and whorls of spindle cells with spindled to ovoid vesicular nuclei, small to medium-sized distinct nucleoli, and eosinophilic cytoplasm were frequently observed. Immunohistochemical staining in the tumor cells was positive for CD163, CD68, lysozyme, CD45, and NSE. Focal expression of CD4 and S-100 was also noted. Electron microscopy demonstrated an abundance of lysosomes in the cytoplasm of tumor cells. Chromosome study revealed a 57–80 hyperdiploid [7]/46, XY [13] karyotype, including 3 to 4 copies of various chromosomes. The immunohistochemical and ultrastructural findings confirmed the diagnosis of HS.

  16. E-cadherin is required for centrosome and spindle orientation in Drosophila male germline stem cells.

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    Mayu Inaba

    2010-08-01

    Full Text Available Many adult stem cells reside in a special microenvironment known as the niche, where they receive essential signals that specify stem cell identity. Cell-cell adhesion mediated by cadherin and integrin plays a crucial role in maintaining stem cells within the niche. In Drosophila melanogaster, male germline stem cells (GSCs are attached to niche component cells (i.e., the hub via adherens junctions. The GSC centrosomes and spindle are oriented toward the hub-GSC junction, where E-cadherin-based adherens junctions are highly concentrated. For this reason, adherens junctions are thought to provide a polarity cue for GSCs to enable proper orientation of centrosomes and spindles, a critical step toward asymmetric stem cell division. However, understanding the role of E-cadherin in GSC polarity has been challenging, since GSCs carrying E-cadherin mutations are not maintained in the niche. Here, we tested whether E-cadherin is required for GSC polarity by expressing a dominant-negative form of E-cadherin. We found that E-cadherin is indeed required for polarizing GSCs toward the hub cells, an effect that may be mediated by Apc2. We also demonstrated that E-cadherin is required for the GSC centrosome orientation checkpoint, which prevents mitosis when centrosomes are not correctly oriented. We propose that E-cadherin orchestrates multiple aspects of stem cell behavior, including polarization of stem cells toward the stem cell-niche interface and adhesion of stem cells to the niche supporting cells.

  17. Localization of spindle checkpoint proteins in cells undergoing mitosis with unreplicated genomes.

    Science.gov (United States)

    Johnson, Mary Kathrine; Cooksey, Amanda M; Wise, Dwayne A

    2008-11-01

    CHO cells can be arrested with hydoxyurea at the beginning of the DNA synthesis phase of the cell cycle. Subsequent treatment with the xanthine, caffeine, induces cells to bypass the S-phase checkpoint and enter unscheduled mitosis [Schlegel and Pardee,1986, Science 232:1264-1266]. These treated cells build a normal spindle and distribute kinetochores, unattached to chromosomes, to their daughter cells [Brinkley et al.,1988, Nature 336:251-254; Zinkowski et al.,1991, J Cell Biol 113:1091-1110; Wise and Brinkley,1997, Cell Motil Cytoskeleton 36:291-302; Balczon et al.,2003, Chromosoma 112:96-102]. To investigate how these cells distribute kinetochores to daughter cells, we analyzed the spindle checkpoint components, Mad2, CENP-E, and the 3F3 phosphoepitope, using immunofluorescence and digital microscopy. Even though the kinetochores were unpaired and DNA was fragmented, the tension, alignment, and motor components of the checkpoint were found to be present and localized as predicted in prometaphase and metaphase. This unusual mitosis proves that a cell can successfully localize checkpoint proteins and divide even when kinetochores are unpaired and fragmented. (c) 2008 Wiley-Liss, Inc.

  18. Inhibition of clathrin by pitstop 2 activates the spindle assembly checkpoint and induces cell death in dividing HeLa cancer cells

    Directory of Open Access Journals (Sweden)

    Smith Charlotte M

    2013-01-01

    Full Text Available Abstract Background During metaphase clathrin stabilises the mitotic spindle kinetochore(K-fibres. Many anti-mitotic compounds target microtubule dynamics. Pitstop 2™ is the first small molecule inhibitor of clathrin terminal domain and inhibits clathrin-mediated endocytosis. We investigated its effects on a second function for clathrin in mitosis. Results Pitstop 2 did not impair clathrin recruitment to the spindle but disrupted its function once stationed there. Pitstop 2 trapped HeLa cells in metaphase through loss of mitotic spindle integrity and activation of the spindle assembly checkpoint, phenocopying clathrin depletion and aurora A kinase inhibition. Conclusions Pitstop 2 is therefore a new tool for investigating clathrin spindle dynamics. Pitstop 2 reduced viability in dividing HeLa cells, without affecting dividing non-cancerous NIH3T3 cells, suggesting that clathrin is a possible novel anti-mitotic drug target.

  19. Mucinous tubular and spindle cell carcinoma of kidney: A clinicopathologic study of six cases

    Directory of Open Access Journals (Sweden)

    Mudassar Hussain

    2012-01-01

    Full Text Available Background: Mucinous tubular and spindle carcinoma (MTSCC of kidney is a rare, low-grade polymorphic tumor. Recent studies have described a wide morphology spectrum of this tumor. Aim: To report the clinico-pathologic features of six cases of MTSCC of kidney. Materials and Methods: Six cases of MTSCC of kidney were studied and literature was reviewed. Immunohistochemistry was done by Envision method. Results: The age of the patients ranged from 44 to 84 years (mean 58.5 years. Four patients were males and two were females. The tumor was located in the left kidney in four cases and in the right kidney in two cases. The tumor size ranged from 4.5 to 15 cm (mean 6.4 cm. All tumors exhibited an admixture of tubules, spindle cells, and mucinous stroma in variable proportions. Tubules were predominant in five cases and spindle cells in one case. Psammomatous calcifications, papillations, and necrosis were seen in two cases. Collections of foamy histiocytes were noted in four cases. Cytoplasmic vacuoles and osseous metaplasia were seen in one case each. All cases were Fuhrman′s nuclear grade II. Five cases were of stage pT1, and one was pT3. All cases stained positive for alcian blue at pH 2.5. Immunohistochemical stain CK7 was positive in all cases and CD10 was positive in 1/1 case. All patients were alive and well at follow-up of 12-59 months (mean 33.5 months. No metastases were detected. Conclusions: We report six cases of MTSCC of kidney, a rare distinct variant of RCC, with a favorable prognosis. A male predominance was seen in our cases. MTSCC shares histologic and immunohistochemical overlap with papillary renal cell carcinoma (PRCC and cytogenetic analysis should be performed in difficult cases to avoid a misdiagnosis.

  20. Mixed Large Cell Neuroendocrine Carcinoma and Adenocarcinoma with Spindle Cell and Clear Cell Features in the Extrahepatic Bile Duct

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    John Wysocki

    2014-01-01

    Full Text Available Mixed adenoneuroendocrine carcinomas, spindle cell carcinomas, and clear cell carcinomas are all rare tumors in the biliary tract. We present the first case, to our knowledge, of an extrahepatic bile duct carcinoma composed of all three types. A 65-year-old man with prior cholecystectomy presented with painless jaundice, vomiting, and weight loss. CA19-9 and alpha-fetoprotein (AFP were elevated. Cholangioscopy revealed a friable mass extending from the middle of the common bile duct to the common hepatic duct. A bile duct excision was performed. Gross examination revealed a 3.6 cm intraluminal polypoid tumor. Microscopically, the tumor had foci of conventional adenocarcinoma (CK7-positive and CA19-9-postive surrounded by malignant-appearing spindle cells that were positive for cytokeratins and vimentin. Additionally, there were separate areas of large cell neuroendocrine carcinoma (LCNEC. Foci of clear cell carcinoma merged into both the LCNEC and the adenocarcinoma. Tumor invaded through the bile duct wall with extensive perineural and vascular invasion. Circumferential margins were positive. The patient’s poor performance status precluded adjuvant therapy and he died with recurrent and metastatic disease 5 months after surgery. This is consistent with the reported poor survival rates of biliary mixed adenoneuroendocrine carcinomas.

  1. Xanthium strumarium extract inhibits mammalian cell proliferation through mitotic spindle disruption mediated by xanthatin.

    Science.gov (United States)

    Sánchez-Lamar, Angel; Piloto-Ferrer, Janet; Fiore, Mario; Stano, Pasquale; Cozzi, Renata; Tofani, Daniela; Cundari, Enrico; Francisco, Marbelis; Romero, Aylema; González, Maria L; Degrassi, Francesca

    2016-12-24

    Xanthium strumarium L. is a member of the Asteraceae family popularly used with multiple therapeutic purposes. Whole extracts of this plant have shown anti-mitotic activity in vitro suggesting that some components could induce mitotic arrest in proliferating cells. Aim of the present work was to characterize the anti-mitotic properties of the X. strumarium whole extract and to isolate and purify active molecule(s). The capacity of the whole extract to inhibit mitotic progression in mammalian cultured cells was investigated to identify its anti-mitotic activity. Isolation of active component(s) was performed using a bioassay-guided multistep separation procedure in which whole extract was submitted to a progressive process of fractionation and fractions were challenged for their anti-mitotic activity. Our results show for the first time that X. strumarium whole extract inhibits assembly of the mitotic spindle and spindle-pole separation, thereby heavily affecting mitosis, impairing the metaphase to anaphase transition and inducing apoptosis. The purification procedure led to a fraction with an anti-mitotic activity comparable to that of the whole extract. Chemical analysis of this fraction showed that its major component was xanthatin. The present work shows a new activity of X. strumarium extract, i.e. the alteration of the mitotic apparatus in cultured cells that may be responsible for the anti-proliferative activity of the extract. Anti-mitotic activity is shown to be mainly exerted by xanthatin. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  2. Spindle cell carcinoma of the breast as complex cystic lesion: a case report

    International Nuclear Information System (INIS)

    Kitada, Masahiro; Hayashi, Satoshi; Matsuda, Yoshinari; Ishibashi, Kei; Oikawa, Keisuke; Miyokawa, Naoyuki

    2014-01-01

    Spindle cell carcinoma of the breast is a rare tumor. This tumor can proliferate rapidly and cause cystic changes because of internal tissue necrosis. We evaluated a 54-year-old woman with right breast lump. Mammography showed a category four mass with a diameter of 2.5 cm. Ultrasonography (US) revealed a complex cystic lesion, and fine-needle aspiration (FNA) cytology demonstrated bloody fluid and malignant cells. Partial breast resection and sentinel lymph node biopsy were performed. Immunohistology revealed spindle cells with positive results for cytokeratin (AE1/AE3) and vimentin, partially positive results for s-100, and negative results for desmin and α-actin. The pathological stage was IIA, and biochemical characterization showed that the tumor was triple negative. Six courses of FEC-100 chemotherapy (5-fluorouracil 500 mg/m 2 , epirubicin 100 mg/m 2 , and cyclophosphamide 500 mg/m 2 ) were administered. Radiotherapy was performed. This case is discussed with reference to the literature

  3. Primary spindle cell sarcoma of the prostate and 18 F-fluorodeoxyglucose-positron-emission tomography/computed tomography findings

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    Hakan Öztürk

    2015-01-01

    Conclusion: Spindle sarcomas of the prostate have quite aggressive nature and they have high potential to metastase. Average life expectancy is <1 year and the prognosis is poor. CTx and radiation therapy can′t yield curative effects due to poor differentiation.

  4. Mucinous tubular and spindle cell carcinoma of kidney: A rare case report and review of the literature

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    Geramizadeh Bita

    2009-10-01

    Full Text Available Low grade mucinous tubular and spindle cell carcinoma of kidney was newly established as a distinct renal cell carcinoma in the World Health Organization (WHO classification of 2004. Until now, less than 60 cases have been reported and the largest series represented approximately 15 patients with this type of tumor. Herein, we report a case of mucinous tubular and spindle cell carcinoma in a 63-year-old male presented with right flank pain which was diagnosed after nephrectomy. Pathologists should consider this diagnosis and its spectrum of histopathologic features in mind to ensure an accurate diagnosis.

  5. New radiological clues in the diagnosis of spindle cell oncocytoma of the adenohypophysis

    International Nuclear Information System (INIS)

    Hasiloglu, Z.I.; Ure, E.; Comunoglu, N.; Tanriover, N.; Oz, B.; Gazioglu, N.; Mihmanli, I.

    2016-01-01

    Aim: To present three new cases of spindle cell oncocytoma (SCO) from a single centre and to identify new radiological clues in the diagnosis of SCO according to the information obtained from the cases presented. Materials and methods: Three adults with SCO confirmed at histopathology were retrospectively reviewed. The medical records, imaging findings, operative notes, and histopathology findings for each patient were recorded. Magnetic resonance imaging (MRI) findings were evaluated, including tumour localisation, tumour size, signal intensity, imaging features on T1-weighted and T2-weighted images, and contrast enhancement characteristics. The study protocol was approved by the institutional review board. Informed consent was obtained from each patient. Results: T1-weighted imaging (WI) and T2WI demonstrated millimetric hypointense foci and linear signal void areas in all lesions. Consistent with the hypervascular features of the tumour, intense contrast enhancement was observed during the early stages of dynamic contrast enhanced (DCE) MRI. Linear signal void areas showed contrast enhancement, but some of the hypointense millimetric foci remained without contrast enhancement. Conclusions: Although the radiological findings and preoperative diagnosis of SCO have been reported to be non-specific and impossible, respectively, in the literature, the characteristics of MRI and different patterns of contrast enhancement can help in recognising this rare entity. This article represents a single institution case series of SCOs and also includes the first description of a correlation of the histopathological findings with radiological findings and new clues in the differential diagnosis of SCOs. We described these new radiological clues as “Hasiloglu's Signs”. - Highlights: • Radiologically, SCOs include hypointense foci and linear signal-void areas on T1-weighted and T2-weighted magnetic resonance imaging. • We confirmed that these hypointense foci may

  6. DNA damage response and spindle assembly checkpoint function throughout the cell cycle to ensure genomic integrity.

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    Katherine S Lawrence

    2015-04-01

    Full Text Available Errors in replication or segregation lead to DNA damage, mutations, and aneuploidies. Consequently, cells monitor these events and delay progression through the cell cycle so repair precedes division. The DNA damage response (DDR, which monitors DNA integrity, and the spindle assembly checkpoint (SAC, which responds to defects in spindle attachment/tension during metaphase of mitosis and meiosis, are critical for preventing genome instability. Here we show that the DDR and SAC function together throughout the cell cycle to ensure genome integrity in C. elegans germ cells. Metaphase defects result in enrichment of SAC and DDR components to chromatin, and both SAC and DDR are required for metaphase delays. During persistent metaphase arrest following establishment of bi-oriented chromosomes, stability of the metaphase plate is compromised in the absence of DDR kinases ATR or CHK1 or SAC components, MAD1/MAD2, suggesting SAC functions in metaphase beyond its interactions with APC activator CDC20. In response to DNA damage, MAD2 and the histone variant CENPA become enriched at the nuclear periphery in a DDR-dependent manner. Further, depletion of either MAD1 or CENPA results in loss of peripherally associated damaged DNA. In contrast to a SAC-insensitive CDC20 mutant, germ cells deficient for SAC or CENPA cannot efficiently repair DNA damage, suggesting that SAC mediates DNA repair through CENPA interactions with the nuclear periphery. We also show that replication perturbations result in relocalization of MAD1/MAD2 in human cells, suggesting that the role of SAC in DNA repair is conserved.

  7. Spindle epithelial tumor with thymus-like differentiation of the thyroid in a 70-year-old man.

    Science.gov (United States)

    Lee, Sunhye; Kim, Yon Seon; Lee, Jeong Hyeon; Hwang, Sung Ho; Oh, Yu-Hwan; Ko, Byung Kyun; Ham, Soo-Youn

    2018-06-01

    Spindle epithelial tumor with thymus-like differentiation (SETTLE) is a very rare tumor of the thyroid gland mostly occurring in young patients. The imaging findings of SETTLE tumors are yet to be defined. However, they are usually described as well-defined heterogeneously enhanced masses on CT scan. The current case has the potential growth as compared with a 2009 chest radiography. We took into account the possibility of SETTLE in the case of a bulky mass in patients over 70 years old, particularly in the lower neck. Herein, we report a case of the oldest patient so far. The patient underwent a right lobectomy of the thyroid and mass excision. Follow-up CT scans after 6 months revealed no local recurrence. Surgery is the gold standard treatment for SETTLE. Chemotherapy and radiotherapy could be another possible option for patients with advanced stage SETTLE.

  8. Cellular angiofibroma: analysis of 25 cases emphasizing its relationship to spindle cell lipoma and mammary-type myofibroblastoma

    NARCIS (Netherlands)

    Flucke, U.E.; Krieken, J.H. van; Mentzel, T.

    2011-01-01

    Cellular angiofibroma represents a rare benign mesenchymal tumor, occurring mainly in the superficial soft tissue of the genital region. The involvement of 13q14 in some cases confirmed the morphological suggested link with spindle cell lipoma and mammary-type myofibroblastoma. We analyzed the

  9. A spindle cell anaplastic pancreatic carcinoma with rhabdoid features following curative resection.

    Science.gov (United States)

    Abe, Tomoyuki; Amano, Hironobu; Hanada, Keiji; Okazaki, Akihisa; Yonehara, Shuji; Kuranishi, Fumito; Nakahara, Masahiro; Kuroda, Yoshinori; Noriyuki, Toshio

    2016-08-01

    Anaplastic pancreatic carcinoma (ANPC) accounts for ~5% of all pancreatic ductal adenocarcinoma cases. Due to its rarity, its clinical features and surgical outcomes remain to be clearly understood. A 74-year-old woman was admitted to Onomichi General Hospital (Onomichi, Japan) in April 2015 without any significant past medical history. Contrast-enhanced computed tomography (CT) revealed a 9.5×8.0 cm tumor in the body and tail of the pancreas. The patient developed acute abdominal pain 3 weeks later and the CT revealed massive abdominal bleeding caused by tumor rupture. The tumor increased in size and reached 12.0×10.0 cm in maximal diameter. The tumor doubling time was estimated to be 13 days. 18 F-fluorodeoxyglucose (FDG) positron emission tomography/CT confirmed the absence of distant metastasis since FDG accumulation was detected only in the tumor lesion. Emergency distal pancreatectomy and splenectomy were performed. Histologically, the tumor was classified as a spindle cell ANPC with rhabdoid features. The patient succumbed to mortality 8 months following the surgery while undergoing systemic adjuvant chemotherapy for multiple liver metastases. ANPC is difficult to detect in the early stages due to its progressive nature and atypical radiological findings. Long-term survival can be achieved only by curative resection; therefore, surgical resection must be performed whenever possible, even if the chance of long-term survival following surgery is considered dismal. As the present case suggested, spindle cell ANPC with rhabdoid features is highly aggressive and curative-intent resection must not be delayed.

  10. Time-sequential observation of spindle and phragmoplast orientation in BY-2 cells with altered cortical actin microfilament patterning.

    Science.gov (United States)

    Kojo, Kei H; Yasuhara, Hiroki; Hasezawa, Seiichiro

    2014-01-01

    Precise division plane determination is essential for plant development. At metaphase, a dense actin microfilament meshwork appears on both sides of the cell center, forming a characteristic cortical actin microfilament twin peak pattern in BY-2 cells. We previously reported a strong correlation between altered cortical actin microfilament patterning and an oblique mitotic spindle orientation, implying that these actin microfilament twin peaks play a role in the regulation of mitotic spindle orientation. In the present study, time-sequential observation was used to reveal the progression from oblique phragmoplast to oblique cell plate orientation in cells with altered cortical actin microfilament patterning. In contrast to cells with normal actin microfilament twin peaks, oblique phragmoplast reorientation was rarely observed in cells with altered cortical actin microfilament patterning. These results support the important roles of cortical actin microfilament patterning in division plane orientation.

  11. Criticality in cell differentiation

    Indian Academy of Sciences (India)

    Indrani Bose

    2017-11-09

    Nov 9, 2017 ... Differentiation is mostly based on binary decisions with the progenitor cells ..... accounts for the dominant part of the remaining variation ... significant loss in information. ..... making in vitro: emerging concepts and novel tools.

  12. Alterations of the spindle checkpoint pathway in clinicopathologically aggressive CpG island methylator phenotype clear cell renal cell carcinomas.

    Science.gov (United States)

    Arai, Eri; Gotoh, Masahiro; Tian, Ying; Sakamoto, Hiromi; Ono, Masaya; Matsuda, Akio; Takahashi, Yoriko; Miyata, Sayaka; Totsuka, Hirohiko; Chiku, Suenori; Komiyama, Motokiyo; Fujimoto, Hiroyuki; Matsumoto, Kenji; Yamada, Tesshi; Yoshida, Teruhiko; Kanai, Yae

    2015-12-01

    CpG-island methylator phenotype (CIMP)-positive clear cell renal cell carcinomas (RCCs) are characterized by accumulation of DNA hypermethylation of CpG islands, clinicopathological aggressiveness and poor patient outcome. The aim of this study was to clarify the molecular pathways participating in CIMP-positive renal carcinogenesis. Genome (whole-exome and copy number), transcriptome and proteome (two-dimensional image converted analysis of liquid chromatography-mass spectrometry) analyses were performed using tissue specimens of 87 CIMP-negative and 14 CIMP-positive clear cell RCCs and corresponding specimens of non-cancerous renal cortex. Genes encoding microtubule-associated proteins, such as DNAH2, DNAH5, DNAH10, RP1 and HAUS8, showed a 10% or higher incidence of genetic aberrations (non-synonymous single-nucleotide mutations and insertions/deletions) in CIMP-positive RCCs, whereas CIMP-negative RCCs lacked distinct genetic characteristics. MetaCore pathway analysis of CIMP-positive RCCs revealed that alterations of mRNA or protein expression were significantly accumulated in six pathways, all participating in the spindle checkpoint, including the "The metaphase checkpoint (p = 1.427 × 10(-6))," "Role of Anaphase Promoting Complex in cell cycle regulation (p = 7.444 × 10(-6))" and "Spindle assembly and chromosome separation (p = 9.260 × 10(-6))" pathways. Quantitative RT-PCR analysis revealed that mRNA expression levels for genes included in such pathways, i.e., AURKA, AURKB, BIRC5, BUB1, CDC20, NEK2 and SPC25, were significantly higher in CIMP-positive than in CIMP-negative RCCs. All CIMP-positive RCCs showed overexpression of Aurora kinases, AURKA and AURKB, and this overexpression was mainly attributable to increased copy number. These data suggest that abnormalities of the spindle checkpoint pathway participate in CIMP-positive renal carcinogenesis, and that AURKA and AURKB may be potential therapeutic targets in more aggressive CIMP-positive RCCs.

  13. Mycobacterium genavense-induced spindle cell pseudotumor in a pediatric hematopoietic stem cell transplant recipient: Case report and review of the literature.

    Science.gov (United States)

    Coelho, Ritika; Hanna, Rabi; Flagg, Aron; Stempak, Lisa M; Ondrejka, Sarah; Procop, Gary W; Harrington, Susan; Zembillas, Anthony; Kusick, Karissa; Gonzalez, Blanca E

    2017-04-01

    We describe the first reported pediatric patient to our knowledge with a spindle cell pseudotumor caused by Mycobacterium genavense in a hematopoietic stem cell transplant recipient, and review the literature of such an entity in the transplant population. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  14. Human ASPM participates in spindle organisation, spindle orientation and cytokinesis

    Directory of Open Access Journals (Sweden)

    Woods C Geoffrey

    2010-11-01

    Full Text Available Abstract Background Mutations in the Abnormal Spindle Microcephaly related gene (ASPM are the commonest cause of autosomal recessive primary microcephaly (MCPH a disorder characterised by a small brain and associated mental retardation. ASPM encodes a mitotic spindle pole associated protein. It is suggested that the MCPH phenotype arises from proliferation defects in neural progenitor cells (NPC. Results We show that ASPM is a microtubule minus end-associated protein that is recruited in a microtubule-dependent manner to the pericentriolar matrix (PCM at the spindle poles during mitosis. ASPM siRNA reduces ASPM protein at the spindle poles in cultured U2OS cells and severely perturbs a number of aspects of mitosis, including the orientation of the mitotic spindle, the main determinant of developmental asymmetrical cell division. The majority of ASPM depleted mitotic cells fail to complete cytokinesis. In MCPH patient fibroblasts we show that a pathogenic ASPM splice site mutation results in the expression of a novel variant protein lacking a tripeptide motif, a minimal alteration that correlates with a dramatic decrease in ASPM spindle pole localisation. Moreover, expression of dominant-negative ASPM C-terminal fragments cause severe spindle assembly defects and cytokinesis failure in cultured cells. Conclusions These observations indicate that ASPM participates in spindle organisation, spindle positioning and cytokinesis in all dividing cells and that the extreme C-terminus of the protein is required for ASPM localisation and function. Our data supports the hypothesis that the MCPH phenotype caused by ASPM mutation is a consequence of mitotic aberrations during neurogenesis. We propose the effects of ASPM mutation are tolerated in somatic cells but have profound consequences for the symmetrical division of NPCs, due to the unusual morphology of these cells. This antagonises the early expansion of the progenitor pool that underpins cortical

  15. Spindle epithelial tumor with thymus-like differentiation of the thyroid gland: A case report with ultrasonography and CT features, cytological findings and histopathological results

    International Nuclear Information System (INIS)

    Kang, Dong Joo; Lee, Yoo Jin; Kim, Dong Wook; Jung, Soo Jin

    2016-01-01

    Spindle epithelial tumor with thymus-like differentiation (SETTLE) of the thyroid gland is a very rare tumor. It is believed to originate from ectopic thymus tissue within the thyroid gland or from branchial pouch remnants that differentiate along the thymic line. A few reports of SETTLE have been presented, but to the best of our knowledge, there is no case report in which detailed preoperative imaging features of SETTLE have been described. In addition, there are no case reports of SETTLE in Korean patients. Thus, we report a case of SETTLE with detailed preoperative ultrasonography and computed tomography features, cytological findings and histopathological results

  16. Spindle epithelial tumor with thymus-like differentiation of the thyroid gland: A case report with ultrasonography and CT features, cytological findings and histopathological results

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Dong Joo; Lee, Yoo Jin; Kim, Dong Wook; Jung, Soo Jin [Busan Paik Hospital, Inje University College of Medicine, Busan (Korea, Republic of)

    2016-11-15

    Spindle epithelial tumor with thymus-like differentiation (SETTLE) of the thyroid gland is a very rare tumor. It is believed to originate from ectopic thymus tissue within the thyroid gland or from branchial pouch remnants that differentiate along the thymic line. A few reports of SETTLE have been presented, but to the best of our knowledge, there is no case report in which detailed preoperative imaging features of SETTLE have been described. In addition, there are no case reports of SETTLE in Korean patients. Thus, we report a case of SETTLE with detailed preoperative ultrasonography and computed tomography features, cytological findings and histopathological results.

  17. Multipolar spindle pole coalescence is a major source of kinetochore mis-attachment and chromosome mis-segregation in cancer cells.

    Directory of Open Access Journals (Sweden)

    William T Silkworth

    Full Text Available Many cancer cells display a CIN (Chromosome Instability phenotype, by which they exhibit high rates of chromosome loss or gain at each cell cycle. Over the years, a number of different mechanisms, including mitotic spindle multipolarity, cytokinesis failure, and merotelic kinetochore orientation, have been proposed as causes of CIN. However, a comprehensive theory of how CIN is perpetuated is still lacking. We used CIN colorectal cancer cells as a model system to investigate the possible cellular mechanism(s underlying CIN. We found that CIN cells frequently assembled multipolar spindles in early mitosis. However, multipolar anaphase cells were very rare, and live-cell experiments showed that almost all CIN cells divided in a bipolar fashion. Moreover, fixed-cell analysis showed high frequencies of merotelically attached lagging chromosomes in bipolar anaphase CIN cells, and higher frequencies of merotelic attachments in multipolar vs. bipolar prometaphases. Finally, we found that multipolar CIN prometaphases typically possessed gamma-tubulin at all spindle poles, and that a significant fraction of bipolar metaphase/early anaphase CIN cells possessed more than one centrosome at a single spindle pole. Taken together, our data suggest a model by which merotelic kinetochore attachments can easily be established in multipolar prometaphases. Most of these multipolar prometaphase cells would then bi-polarize before anaphase onset, and the residual merotelic attachments would produce chromosome mis-segregation due to anaphase lagging chromosomes. We propose this spindle pole coalescence mechanism as a major contributor to chromosome instability in cancer cells.

  18. Taxifolin enhances andrographolide-induced mitotic arrest and apoptosis in human prostate cancer cells via spindle assembly checkpoint activation.

    Directory of Open Access Journals (Sweden)

    Zhong Rong Zhang

    Full Text Available Andrographolide (Andro suppresses proliferation and triggers apoptosis in many types of cancer cells. Taxifolin (Taxi has been proposed to prevent cancer development similar to other dietary flavonoids. In the present study, the cytotoxic and apoptotic effects of the addition of Andro alone and Andro and Taxi together on human prostate carcinoma DU145 cells were assessed. Andro inhibited prostate cancer cell proliferation by mitotic arrest and activation of the intrinsic apoptotic pathway. Although the effect of Taxi alone on DU145 cell proliferation was not significant, the combined use of Taxi with Andro significantly potentiated the anti-proliferative effect of increased mitotic arrest and apoptosis by enhancing the cleavage of poly(ADP-ribose polymerase, and caspases-7 and -9. Andro together with Taxi enhanced microtubule polymerization in vitro, and they induced the formation of twisted and elongated spindles in the cancer cells, thus leading to mitotic arrest. In addition, we showed that depletion of MAD2, a component in the spindle assembly checkpoint (SAC, alleviated the mitotic block induced by the two compounds, suggesting that they trigger mitotic arrest by SAC activation. This study suggests that the anti-cancer activity of Andro can be significantly enhanced in combination with Taxi by disrupting microtubule dynamics and activating the SAC.

  19. Taxifolin Enhances Andrographolide-Induced Mitotic Arrest and Apoptosis in Human Prostate Cancer Cells via Spindle Assembly Checkpoint Activation

    Science.gov (United States)

    Wong, Matthew Man-Kin; Chiu, Sung-Kay; Cheung, Hon-Yeung

    2013-01-01

    Andrographolide (Andro) suppresses proliferation and triggers apoptosis in many types of cancer cells. Taxifolin (Taxi) has been proposed to prevent cancer development similar to other dietary flavonoids. In the present study, the cytotoxic and apoptotic effects of the addition of Andro alone and Andro and Taxi together on human prostate carcinoma DU145 cells were assessed. Andro inhibited prostate cancer cell proliferation by mitotic arrest and activation of the intrinsic apoptotic pathway. Although the effect of Taxi alone on DU145 cell proliferation was not significant, the combined use of Taxi with Andro significantly potentiated the anti-proliferative effect of increased mitotic arrest and apoptosis by enhancing the cleavage of poly(ADP-ribose) polymerase, and caspases-7 and -9. Andro together with Taxi enhanced microtubule polymerization in vitro, and they induced the formation of twisted and elongated spindles in the cancer cells, thus leading to mitotic arrest. In addition, we showed that depletion of MAD2, a component in the spindle assembly checkpoint (SAC), alleviated the mitotic block induced by the two compounds, suggesting that they trigger mitotic arrest by SAC activation. This study suggests that the anti-cancer activity of Andro can be significantly enhanced in combination with Taxi by disrupting microtubule dynamics and activating the SAC. PMID:23382917

  20. Gemcitabine and docetaxel in relapsed and unresectable high-grade osteosarcoma and spindle cell sarcoma of bone

    OpenAIRE

    Palmerini, E.; Jones, R. L.; Marchesi, E.; Paioli, A.; Cesari, M.; Longhi, A.; Meazza, C.; Coccoli, L.; Fagioli, F.; Asaftei, S.; Grignani, G.; Tamburini, A.; Pollack, S. M.; Picci, P.; Ferrari, S.

    2016-01-01

    Background Few new compounds are available for relapsed osteosarcoma. We retrospectively evaluated the activity of gemcitabine (G) plus docetaxel (D) in patients with relapsed high-grade osteosarcoma and high-grade spindle cell sarcoma of bone (HGS). Methods Patients receiving G 900?mg/m2 d 1, 8; D 75?mg/m2 d 8, every 21?days were eligible. Primary end-point: progression-free survival (PFS) at 4?months; secondary end-point: overall survival (OS) and response rate. Results Fifty-one patients w...

  1. Short-Spindled Cell Haemangioblastoma with CD34 Expression: New Histopathological Variant or Just a Stochastic Cytological Singularity?

    Directory of Open Access Journals (Sweden)

    Miguel Fdo. Salazar

    2016-01-01

    Full Text Available Haemangioblastomas are neoplasms of uncertain histogenesis with cellular and reticular variants advocated in current lore. Herein we describe an intriguing cerebellar specimen with unusual traits including spindle cell morphology and CD34 positivity. A thirty-nine-year old man had an infratentorial tumour discovered incidentally and resected three times. In all the instances, histopathological diagnosis was haemangioblastoma; nonetheless, he had neither physical stigmata nor family history of von Hippel-Lindau disease. By histology, the lesion was composed of areas of conventional stromal cells admixed with territories populated by short-spindled cells packed in lobules, sometimes giving the appearance of gomitoli. Immunoperoxidase-coupled reactions confirmed the expression of inhibin A, neuron-specific enolase (NSE, PS100, and CD57 but also revealed focal immunolabeling for CD34, CD99, and FXIIIa. This case highlights the potential phenotypical diversity that can be found within these neoplasms. Rather than uncertain histogenesis, it may in fact reflect multiple lines of differentiation—histomimesis—prone to adopt unusual morpho- and immunophenotypes in a subset of haemangioblastomas.

  2. Osteoblastic cells: differentiation and trans-differentiation

    DEFF Research Database (Denmark)

    Kassem, Moustapha; Abdallah, Basem; Saeed, Hamid

    2008-01-01

    The osteoblast is the bone forming cell and is derived from mesenchymal stem cells (MSC) present among the bone marrow stroma. MSC are capable of multi-lineage differentiation into mesoderm-type cells such as osteoblasts and adipocytes. Understanding the mechanisms underlying osteoblast different...

  3. Paracetamol-induced spindle disturbances in V79 cells with and without expression of human CYP1A2

    DEFF Research Database (Denmark)

    Jensen, K G; Poulsen, H E; Doehmer, J

    1996-01-01

    Spindle disturbing effects in terms of c-mitosis and cytotoxicity of paracetamol were investigated in two Chinese hamster V79 cell lines, one of which (V79MZh1A2) was transfected with human CYP1A2. This enzyme catalyses the oxidative formation of the reactive paracetamol metabolite, NAPQI, believed...... to initiate hepatoxicity by covalent binding to proteins after overdose. In the native V79 cell line paracetamol increased c-mitosis frequency in a concentration dependent manner from 8.7 + or - 3.5% (control) to 66 + or - 18% at 20 mM. A significant increase to 13.3 + or - 3.5% was first seen at 2.5 m......M in the native cell line (Pparacetamol. At 5 mM paracetamol the c-mitosis frequency was 14.4 + or - 5.0% and 19.0 + or - 3...

  4. Mechanical design principles of a mitotic spindle.

    Science.gov (United States)

    Ward, Jonathan J; Roque, Hélio; Antony, Claude; Nédélec, François

    2014-12-18

    An organised spindle is crucial to the fidelity of chromosome segregation, but the relationship between spindle structure and function is not well understood in any cell type. The anaphase B spindle in fission yeast has a slender morphology and must elongate against compressive forces. This 'pushing' mode of chromosome transport renders the spindle susceptible to breakage, as observed in cells with a variety of defects. Here we perform electron tomographic analyses of the spindle, which suggest that it organises a limited supply of structural components to increase its compressive strength. Structural integrity is maintained throughout the spindle's fourfold elongation by organising microtubules into a rigid transverse array, preserving correct microtubule number and dynamically rescaling microtubule length.

  5. Role of immunohistochemistry and fluorescence in-situ hybridization (FISH in the diagnosis of spindle and round cell tumors of the kidney

    Directory of Open Access Journals (Sweden)

    M. Abbas

    2015-09-01

    Conclusion: In summary we advise an immunohistochemical panel for round/spindle cell tumors of the kidney and for unclear cases we advise to add (FISH to get the correct diagnosis, as they are completely different regarding surgical approach and post-operative adjuvant therapy.

  6. Unusual case of spindle cell sarcoma metastases to right ventricle: a case report and a literature review.

    Science.gov (United States)

    Frakulli, Rezarta; Cammelli, Silvia; Salvi, Fabrizio; Balestrini, Damiano; Baldissera, Antonella; Degli Esposti, Claudio; Martelli, Ombretta; Abate, Massimo; Piaoli, Anna; Ferrari, Stefano; Morganti, Alessio G; Frezza, Giovanni Piero

    2017-09-01

    Cardiac metastases from sarcoma are uncommon. Due to their rarity there is not a standard of care. However, complete cardiac metastases resection is the best option but most of patients has widespread disease. In these patients palliative radiotherapy (RT) might improve symptoms and prevent further cardiac function decline. Here we present the case of a symptomatic 30-year-old woman with spindle cell sarcoma metastasis of right ventriculum and widespread disease. The patient received radiotherapy to the heart with palliative intent. Cardiac metastases represent a challenging clinic problem. Treatment should be individualized in a multidisciplinary setting, when possible surgery seems to be the best options. However, radiotherapy even in case of widespread disease can improve clinical control symptoms by reducing the mass effect.

  7. Intimal spindle cell sarcoma masquerading as adult-onset symptomatic pulmonic stenosis: a case report and review of the literature.

    Science.gov (United States)

    Manmadhan, Arun; Malhotra, Sunil P; Weinberg, Catherine R; Reyentovich, Alex; Latson, Larry A; Bhatla, Puneet; Saric, Muhamed

    2017-10-30

    Pulmonary artery intimal spindle cell sarcomas are rare and carry with them a poor prognosis and high rate of recurrence. In extremely rare cases, this tumor can infiltrate the pulmonic valve and manifest as adult-onset pulmonic stenosis. We report an unusual case of a patient with symptomatic, adult-onset severe pulmonic stenosis who was referred for possible balloon valvuloplasty but was subsequently found to have pulmonary artery intimal sarcoma infiltrating the pulmonary valve leading to progressive exertional dyspnea. The presence of adult-onset pulmonic stenosis should prompt the clinician to investigate further as most cases of pulmonic stenosis are congenital in nature and present early in life. Careful diagnostic evaluation in concert with multimodal imaging should take place to arrive at the correct and challenging diagnosis of sarcoma-induced adult-onset severe pulmonic stenosis. Given the poor prognosis and rapid progression of disease, early diagnosis is crucial.

  8. Intimal spindle cell sarcoma masquerading as adult-onset symptomatic pulmonic stenosis: a case report and review of the literature

    Directory of Open Access Journals (Sweden)

    Arun Manmadhan

    2017-10-01

    Full Text Available Abstract Background Pulmonary artery intimal spindle cell sarcomas are rare and carry with them a poor prognosis and high rate of recurrence. In extremely rare cases, this tumor can infiltrate the pulmonic valve and manifest as adult-onset pulmonic stenosis. Case presentation We report an unusual case of a patient with symptomatic, adult-onset severe pulmonic stenosis who was referred for possible balloon valvuloplasty but was subsequently found to have pulmonary artery intimal sarcoma infiltrating the pulmonary valve leading to progressive exertional dyspnea. Conclusion The presence of adult-onset pulmonic stenosis should prompt the clinician to investigate further as most cases of pulmonic stenosis are congenital in nature and present early in life. Careful diagnostic evaluation in concert with multimodal imaging should take place to arrive at the correct and challenging diagnosis of sarcoma-induced adult-onset severe pulmonic stenosis. Given the poor prognosis and rapid progression of disease, early diagnosis is crucial.

  9. CT and MR imaging features of mucinous tubular and spindle cell carcinoma of the kidneys. A multi-institutional review

    Energy Technology Data Exchange (ETDEWEB)

    Cornelis, F.; Grenier, N. [Pellegrin Hospital, Department of Radiology, Bordeaux (France); Ambrosetti, D. [Pasteur Hospital, Department of Pathology, Nice (France); Rocher, L. [Kremlin-Bicetre Hospital, Department of Radiology, Paris (France); Derchi, L.E. [University of Genoa, IRCCS AOU Ospedale, San Martino IST, Department of Health Sciences (DISSAL), Genoa (Italy); Renard, B.; Puech, P. [Claude Huriez Hospital, Department of Radiology, Lille (France); Claudon, M. [Brabois Hospital, Department of Radiology, Vandoeuvre-les-Nancy (France); Rouviere, O. [E. Herriot Hospital, Department of Radiology, Lyon (France); Ferlicot, S. [Kremlin-Bicetre Hospital, Department of Pathology, Paris (France); Roy, C. [Civil Hospital, Department of Radiology, Strasbourg (France); Yacoub, M. [Pellegrin Hospital, Department of Pathology, Bordeaux (France); Bernhard, J.C. [Pellegrin Hospital, Department of Urologic Surgery, Bordeaux (France)

    2017-03-15

    Mucinous tubular and spindle cell carcinoma (MTSCC) of the kidney is a recently identified renal malignancy. Diagnosis of this rare subtype of renal tumour can be challenging for pathologists, and as such, any additional data would be helpful to improve diagnostic reliability. As imaging features of this new and rare sub-type have not yet been clearly described, the purpose of this study was to describe the main radiologic features on computed tomography (CT) and magnetic resonance imaging (MRI), based jointly on the literature and findings from a multi-institutional retrospective review of pathology and imaging databases. Using a combination of CT/MRI features, diagnosis of MTSCC could be suggested in many cases. A combination of slow enhancement with plateau on dynamic contrast-enhanced CT/MRI, intermediate to high T2 signal intensity contrasting with low apparent diffusion coefficient values on MRI appeared evocative of this diagnosis. (orig.)

  10. When the genome plays dice: circumvention of the spindle assembly checkpoint and near-random chromosome segregation in multipolar cancer cell mitoses.

    Science.gov (United States)

    Gisselsson, David; Håkanson, Ulf; Stoller, Patrick; Marti, Dominik; Jin, Yuesheng; Rosengren, Anders H; Stewénius, Ylva; Kahl, Fredrik; Panagopoulos, Ioannis

    2008-04-02

    Normal cell division is coordinated by a bipolar mitotic spindle, ensuring symmetrical segregation of chromosomes. Cancer cells, however, occasionally divide into three or more directions. Such multipolar mitoses have been proposed to generate genetic diversity and thereby contribute to clonal evolution. However, this notion has been little validated experimentally. Chromosome segregation and DNA content in daughter cells from multipolar mitoses were assessed by multiphoton cross sectioning and fluorescence in situ hybridization in cancer cells and non-neoplastic transformed cells. The DNA distribution resulting from multipolar cell division was found to be highly variable, with frequent nullisomies in the daughter cells. Time-lapse imaging of H2B/GFP-labelled multipolar mitoses revealed that the time from the initiation of metaphase to the beginning of anaphase was prolonged and that the metaphase plates often switched polarity several times before metaphase-anaphase transition. The multipolar metaphase-anaphase transition was accompanied by a normal reduction of cellular cyclin B levels, but typically occurred before completion of the normal separase activity cycle. Centromeric AURKB and MAD2 foci were observed frequently to remain on the centromeres of multipolar ana-telophase chromosomes, indicating that multipolar mitoses were able to circumvent the spindle assembly checkpoint with some sister chromatids remaining unseparated after anaphase. Accordingly, scoring the distribution of individual chromosomes in multipolar daughter nuclei revealed a high frequency of nondisjunction events, resulting in a near-binomial allotment of sister chromatids to the daughter cells. The capability of multipolar mitoses to circumvent the spindle assembly checkpoint system typically results in a near-random distribution of chromosomes to daughter cells. Spindle multipolarity could thus be a highly efficient generator of genetically diverse minority clones in transformed cell

  11. When the genome plays dice: circumvention of the spindle assembly checkpoint and near-random chromosome segregation in multipolar cancer cell mitoses.

    Directory of Open Access Journals (Sweden)

    David Gisselsson

    Full Text Available BACKGROUND: Normal cell division is coordinated by a bipolar mitotic spindle, ensuring symmetrical segregation of chromosomes. Cancer cells, however, occasionally divide into three or more directions. Such multipolar mitoses have been proposed to generate genetic diversity and thereby contribute to clonal evolution. However, this notion has been little validated experimentally. PRINCIPAL FINDINGS: Chromosome segregation and DNA content in daughter cells from multipolar mitoses were assessed by multiphoton cross sectioning and fluorescence in situ hybridization in cancer cells and non-neoplastic transformed cells. The DNA distribution resulting from multipolar cell division was found to be highly variable, with frequent nullisomies in the daughter cells. Time-lapse imaging of H2B/GFP-labelled multipolar mitoses revealed that the time from the initiation of metaphase to the beginning of anaphase was prolonged and that the metaphase plates often switched polarity several times before metaphase-anaphase transition. The multipolar metaphase-anaphase transition was accompanied by a normal reduction of cellular cyclin B levels, but typically occurred before completion of the normal separase activity cycle. Centromeric AURKB and MAD2 foci were observed frequently to remain on the centromeres of multipolar ana-telophase chromosomes, indicating that multipolar mitoses were able to circumvent the spindle assembly checkpoint with some sister chromatids remaining unseparated after anaphase. Accordingly, scoring the distribution of individual chromosomes in multipolar daughter nuclei revealed a high frequency of nondisjunction events, resulting in a near-binomial allotment of sister chromatids to the daughter cells. CONCLUSION: The capability of multipolar mitoses to circumvent the spindle assembly checkpoint system typically results in a near-random distribution of chromosomes to daughter cells. Spindle multipolarity could thus be a highly efficient

  12. Methylglyoxal Induced Basophilic Spindle Cells with Podoplanin at the Surface of Peritoneum in Rat Peritoneal Dialysis Model

    Directory of Open Access Journals (Sweden)

    Ichiro Hirahara

    2015-01-01

    Full Text Available Peritoneal dialysis (PD is a common treatment for patients with reduced or absent renal function. Long-term PD leads to peritoneal injury with structural changes and functional decline. At worst, peritoneal injury leads to encapsulating peritoneal sclerosis (EPS, which is a serious complication of PD. In order to carry out PD safely, it is important to define the mechanism of progression of peritoneal injury and EPS. We prepared rat models of peritoneal injury by intraperitoneal administration of glucose degradation products, such as methylglyoxal (MGO or formaldehyde (FA, chlorhexidine gluconate (CG, and talc. In rats treated with MGO, peritoneal fibrous thickening with the appearance of basophilic spindle cells with podoplanin, cytokeratin, and α-smooth muscle actin at the surface of the peritoneum was observed. These cells may have been derived from mesothelial cells by epithelial-to-mesenchymal transition. In FA- or CG-treated rats, the peritoneum was thickened, and mesothelial cells were absent at the surface of the peritoneum. The CG- or MGO-treated rats presented with a so-called abdominal cocoon. In the talc-treated rats, extensive peritoneal adhesion and peritoneal thickening were observed. MGO-induced peritoneal injury model may reflect human histopathology and be suitable to analyze the mechanism of progression of peritoneal injury and EPS.

  13. The Spindle Assembly Checkpoint Is Not Essential for Viability of Human Cells with Genetically Lowered APC/C Activity.

    Science.gov (United States)

    Wild, Thomas; Larsen, Marie Sofie Yoo; Narita, Takeo; Schou, Julie; Nilsson, Jakob; Choudhary, Chunaram

    2016-03-01

    The anaphase-promoting complex/cyclosome (APC/C) and the spindle assembly checkpoint (SAC), which inhibits the APC/C, are essential determinants of mitotic timing and faithful division of genetic material. Activation of the APC/C is known to depend on two APC/C-interacting E2 ubiquitin-conjugating enzymes-UBE2C and UBE2S. We show that APC/C activity in human cells is tuned by the combinatorial use of three E2s, namely UBE2C, UBE2S, and UBE2D. Genetic deletion of UBE2C and UBE2S, individually or in combination, leads to discriminative reduction in APC/C function and sensitizes cells to UBE2D depletion. Reduction of APC/C activity results in loss of switch-like metaphase-to-anaphase transition and, strikingly, renders cells insensitive to chemical inhibition of MPS1 and genetic ablation of MAD2, both of which are essential for the SAC. These results provide insights into the regulation of APC/C activity and demonstrate that the essentiality of the SAC is imposed by the strength of the APC/C. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  14. The Spindle Assembly Checkpoint Is Not Essential for Viability of Human Cells with Genetically Lowered APC/C Activity

    DEFF Research Database (Denmark)

    Wild, Thomas; Larsen, Marie Sofie Yoo; Narita, Takeo

    2016-01-01

    The anaphase-promoting complex/cyclosome (APC/C) and the spindle assembly checkpoint (SAC), which inhibits the APC/C, are essential determinants of mitotic timing and faithful division of genetic material. Activation of the APC/C is known to depend on two APC/C-interacting E2 ubiquitin......-conjugating enzymes-UBE2C and UBE2S. We show that APC/C activity in human cells is tuned by the combinatorial use of three E2s, namely UBE2C, UBE2S, and UBE2D. Genetic deletion of UBE2C and UBE2S, individually or in combination, leads to discriminative reduction in APC/C function and sensitizes cells to UBE2D...... depletion. Reduction of APC/C activity results in loss of switch-like metaphase-to-anaphase transition and, strikingly, renders cells insensitive to chemical inhibition of MPS1 and genetic ablation of MAD2, both of which are essential for the SAC. These results provide insights into the regulation of APC...

  15. Measuring mitotic spindle dynamics in budding yeast

    Science.gov (United States)

    Plumb, Kemp

    In order to carry out its life cycle and produce viable progeny through cell division, a cell must successfully coordinate and execute a number of complex processes with high fidelity, in an environment dominated by thermal noise. One important example of such a process is the assembly and positioning of the mitotic spindle prior to chromosome segregation. The mitotic spindle is a modular structure composed of two spindle pole bodies, separated in space and spanned by filamentous proteins called microtubules, along which the genetic material of the cell is held. The spindle is responsible for alignment and subsequent segregation of chromosomes into two equal parts; proper spindle positioning and timing ensure that genetic material is appropriately divided amongst mother and daughter cells. In this thesis, I describe fluorescence confocal microscopy and automated image analysis algorithms, which I have used to observe and analyze the real space dynamics of the mitotic spindle in budding yeast. The software can locate structures in three spatial dimensions and track their movement in time. By selecting fluorescent proteins which specifically label the spindle poles and cell periphery, mitotic spindle dynamics have been measured in a coordinate system relevant to the cell division. I describe how I have characterised the accuracy and precision of the algorithms by simulating fluorescence data for both spindle poles and the budding yeast cell surface. In this thesis I also describe the construction of a microfluidic apparatus that allows for the measurement of long time-scale dynamics of individual cells and the development of a cell population. The tools developed in this thesis work will facilitate in-depth quantitative analysis of the non-equilibrium processes in living cells.

  16. An unusual and spectacular case of spindle cell lipoma of the posterior neck invading the spinal cervical canal and posterior cranial fossa.

    Science.gov (United States)

    Petit, Damien; Menei, Philippe; Fournier, Henri-Dominique

    2011-11-01

    The authors describe the first case of spindle cell lipoma of the posterior neck invading the upper cervical spinal canal and the posterior cranial fossa. Spindle cell lipoma is an extremely rare variant of benign lipoma. It usually occurs as a solitary subcutaneous well-circumscribed lesion in the posterior neck or shoulders of adult men. Local aggressiveness is unusual. This 61-year-old man presented with an increased left cerebellar syndrome and headaches. He also had a posterior neck tumefaction, which had been known about for a long time. Computed tomography and MR imaging studies revealed a voluminous mass extending to the upper cervical canal and posterior cranial fossa and eroding the neighboring bones. The lesion was well delimited, and contrast enhancement was intense and heterogeneous. The tumor, which had initially developed under the muscles of the posterior neck, was totally resected. Histological assessment revealed numerous fat cells with spindle cells secreting collagen. The large size of the tumor and the submuscular location, bone erosion, and compression of the CNS were unusual in this rare subtype of benign adipose tumor. Its presentation could simulate a sarcoma.

  17. Trading in your spindles for blebs: the amoeboid tumor cell phenotype in prostate cancer

    Directory of Open Access Journals (Sweden)

    Samantha Morley

    2014-08-01

    Full Text Available Prostate cancer (PCa remains a principal cause of mortality in developed countries. Because no clinical interventions overcome resistance to androgen ablation therapy, management of castration resistance and metastatic disease remains largely untreatable. Metastasis is a multistep process in which tumor cells lose cell-cell contacts, egress from the primary tumor, intravasate, survive shear stress within the vasculature and extravasate into tissues to colonize ectopic sites. Tumor cells reestablish migratory behaviors employed during nonneoplastic processes such as embryonic development, leukocyte trafficking and wound healing. While mesenchymal motility is an established paradigm of dissemination, an alternate, 'amoeboid' phenotype is increasingly appreciated as relevant to human cancer. Here we discuss characteristics and pathways underlying the phenotype, and highlight our findings that the cytoskeletal regulator DIAPH3 governs the mesenchymal-amoeboid transition. We also describe our identification of a new class of tumor-derived microvesicles, large oncosomes, produced by amoeboid cells and with potential clinical utility in prostate and other cancers.

  18. Gastrointestinal tract spindle cell lesions--just like real estate, it's all about location.

    Science.gov (United States)

    Voltaggio, Lysandra; Montgomery, Elizabeth A

    2015-01-01

    Interpretation of gastrointestinal tract mesenchymal lesions is simplified merely by knowing in which anatomic layer they are usually found. For example, Kaposi sarcoma is detected on mucosal biopsies, whereas inflammatory fibroid polyp is nearly always in the submucosa. Gastrointestinal stromal tumors (GISTs) are generally centered in the muscularis propria. Schwannomas are essentially always in the muscularis propria. Mesenteric lesions are usually found in the small bowel mesentery. Knowledge of the favored layer is even most important in interpreting colon biopsies, as many mesenschymal polyps are encountered in the colon. Although GISTs are among the most common mesenchymal lesions, we will concentrate our discussion on other mesenchymal lesions, some of which are in the differential diagnosis of GIST, and point out some diagnostic pitfalls, particularly in immunolabeling.

  19. Capacity of Human Dental Follicle Cells to Differentiate into Neural Cells In Vitro

    Directory of Open Access Journals (Sweden)

    Shingo Kanao

    2017-01-01

    Full Text Available The dental follicle is an ectomesenchymal tissue surrounding the developing tooth germ. Human dental follicle cells (hDFCs have the capacity to commit to differentiation into multiple cell types. Here we investigated the capacity of hDFCs to differentiate into neural cells and the efficiency of a two-step strategy involving floating neurosphere-like bodies for neural differentiation. Undifferentiated hDFCs showed a spindle-like morphology and were positive for neural markers such as nestin, β-III-tubulin, and S100β. The cellular morphology of several cells was neuronal-like including branched dendrite-like processes and neurites. Next, hDFCs were used for neurosphere formation in serum-free medium containing basic fibroblast growth factor, epidermal growth factor, and B27 supplement. The number of cells with neuronal-like morphology and that were strongly positive for neural markers increased with sphere formation. Gene expression of neural markers also increased in hDFCs with sphere formation. Next, gene expression of neural markers was examined in hDFCs during neuronal differentiation after sphere formation. Expression of Musashi-1 and Musashi-2, MAP2, GFAP, MBP, and SOX10 was upregulated in hDFCs undergoing neuronal differentiation via neurospheres, whereas expression of nestin and β-III-tubulin was downregulated. In conclusion, hDFCs may be another optimal source of neural/glial cells for cell-based therapies to treat neurological diseases.

  20. Gemcitabine and docetaxel in relapsed and unresectable high-grade osteosarcoma and spindle cell sarcoma of bone.

    Science.gov (United States)

    Palmerini, E; Jones, R L; Marchesi, E; Paioli, A; Cesari, M; Longhi, A; Meazza, C; Coccoli, L; Fagioli, F; Asaftei, S; Grignani, G; Tamburini, A; Pollack, S M; Picci, P; Ferrari, S

    2016-04-20

    Few new compounds are available for relapsed osteosarcoma. We retrospectively evaluated the activity of gemcitabine (G) plus docetaxel (D) in patients with relapsed high-grade osteosarcoma and high-grade spindle cell sarcoma of bone (HGS). Patients receiving G 900 mg/m(2) d 1, 8; D 75 mg/m(2) d 8, every 21 days were eligible. Primary end-point: progression-free survival (PFS) at 4 months; secondary end-point: overall survival (OS) and response rate. Fifty-one patients were included, with a median age of 17 years (8-71), 26 (51%) were pediatric patients. GD line of treatment: 2nd in 14 patients, ≥3rd in 37. 25 (49%) patients had metastases limited to lungs, 26 (51%) multiple sites. 40 (78%) osteosarcoma, 11 (22%) HGS. Eight (16%) patients achieved surgical complete response (sCR2) after GD. Four-month PFS rate was 46%, and significantly better for patients with ECOG 0 (ECOG 0: 54% vs ECOG 1: 43% vs ECOG 2: 0%; p = 0.003), for patients undergoing metastasectomy after GD (sCR2 75% vs no-sCR2 40 %, p = 0.02) and for osteosarcoma (osteosarcoma 56% vs HGS 18%; p = 0.05), with no differences according to age, line of treatment, and pattern of metastases. Forty-six cases had RECIST measurable disease: 6 (13%) patients had a partial response (PR), 20 (43%) had stable disease (SD) and 20 (43%) had progressive disease (PD). The 1-year OS was 30%: 67% for PR, 54% for SD and 20% for PD (p = 0.005). GD is an active treatment for relapsed high-grade osteosarcoma, especially for ECOG 0 patients, and should be included in the therapeutic armamentarium of metastatic osteosarcoma.

  1. Gemcitabine and docetaxel in relapsed and unresectable high-grade osteosarcoma and spindle cell sarcoma of bone

    International Nuclear Information System (INIS)

    Palmerini, E.; Jones, R. L.; Marchesi, E.; Paioli, A.; Cesari, M.; Longhi, A.; Meazza, C.; Coccoli, L.; Fagioli, F.; Asaftei, S.; Grignani, G.; Tamburini, A.; Pollack, S. M.; Picci, P.; Ferrari, S.

    2016-01-01

    Few new compounds are available for relapsed osteosarcoma. We retrospectively evaluated the activity of gemcitabine (G) plus docetaxel (D) in patients with relapsed high-grade osteosarcoma and high-grade spindle cell sarcoma of bone (HGS). Patients receiving G 900 mg/m 2 d 1, 8; D 75 mg/m 2 d 8, every 21 days were eligible. Primary end-point: progression-free survival (PFS) at 4 months; secondary end-point: overall survival (OS) and response rate. Fifty-one patients were included, with a median age of 17 years (8–71), 26 (51 %) were pediatric patients. GD line of treatment: 2nd in 14 patients, ≥3rd in 37. 25 (49 %) patients had metastases limited to lungs, 26 (51 %) multiple sites. Histology: 40 (78 %) osteosarcoma, 11 (22 %) HGS. Eight (16 %) patients achieved surgical complete response (sCR2) after GD. Four-month PFS rate was 46 %, and significantly better for patients with ECOG 0 (ECOG 0: 54 % vs ECOG 1: 43 % vs ECOG 2: 0 %; p = 0.003), for patients undergoing metastasectomy after GD (sCR2 75 % vs no-sCR2 40 %, p = 0.02) and for osteosarcoma (osteosarcoma 56 % vs HGS 18 %; p = 0.05), with no differences according to age, line of treatment, and pattern of metastases. Forty-six cases had RECIST measurable disease: 6 (13 %) patients had a partial response (PR), 20 (43 %) had stable disease (SD) and 20 (43 %) had progressive disease (PD). The 1-year OS was 30 %: 67 % for PR, 54 % for SD and 20 % for PD (p = 0.005). GD is an active treatment for relapsed high-grade osteosarcoma, especially for ECOG 0 patients, and should be included in the therapeutic armamentarium of metastatic osteosarcoma

  2. Mitochondria in aging cell differentiation

    Czech Academy of Sciences Publication Activity Database

    Palková, Zdena; Váchová, Libuše

    2016-01-01

    Roč. 8, č. 7 (2016), s. 1287-1288 ISSN 1945-4589 R&D Projects: GA MŠk(CZ) ED1.1.00/02.0109 Institutional support: RVO:61388971 Keywords : mitochondria * cell differentiation * retrograde signaling Subject RIV: EE - Microbiology, Virology Impact factor: 4.867, year: 2016

  3. Airborne urban particles (Milan winter-PM2.5) cause mitotic arrest and cell death: Effects on DNA, mitochondria, AhR binding and spindle organization

    Energy Technology Data Exchange (ETDEWEB)

    Gualtieri, Maurizio [Applied Cell Biology and Particles Effects, Department of Environmental Science, University Milano-Bicocca, Piazza della Scienza 1, 20126 Milano (Italy); Division of Environmental Medicine, Norwegian Institute of Public Health, P.O. Box 4404 Nydalen, N-0403 Oslo (Norway); Ovrevik, Johan [Division of Environmental Medicine, Norwegian Institute of Public Health, P.O. Box 4404 Nydalen, N-0403 Oslo (Norway); Mollerup, Steen [Section for Toxicology, National Institute of Occupational Health, N-0033 Oslo (Norway); Asare, Nana [Division of Environmental Medicine, Norwegian Institute of Public Health, P.O. Box 4404 Nydalen, N-0403 Oslo (Norway); Longhin, Eleonora [Applied Cell Biology and Particles Effects, Department of Environmental Science, University Milano-Bicocca, Piazza della Scienza 1, 20126 Milano (Italy); Dahlman, Hans-Jorgen [Division of Environmental Medicine, Norwegian Institute of Public Health, P.O. Box 4404 Nydalen, N-0403 Oslo (Norway); Camatini, Marina [Applied Cell Biology and Particles Effects, Department of Environmental Science, University Milano-Bicocca, Piazza della Scienza 1, 20126 Milano (Italy); Centre Research POLARIS, Department of Environmental Science, University Milano-Bicocca, Piazza della Scienza 1, 20126 Milano (Italy); Holme, Jorn A., E-mail: jorn.holme@fhi.no [Division of Environmental Medicine, Norwegian Institute of Public Health, P.O. Box 4404 Nydalen, N-0403 Oslo (Norway)

    2011-08-01

    Highlights: {yields} PM2.5 induces mitotic arrest in BEAS-2B cells. {yields} PM2.5 induces DNA damage and activates DNA damage response. {yields} AhR regulated genes (Cyp1A1, Cyp1B1 and AhRR) are upregulated after PM exposure. {yields} Mitotic spindle assembly is perturbed in PM exposed cells. - Abstract: Airborne particulate matter (PM) is considered to be an important contributor to lung diseases. In the present study we report that Milan winter-PM2.5 inhibited proliferation in human bronchial epithelial cells (BEAS-2B) by inducing mitotic arrest. The cell cycle arrest was followed by an increase in mitotic-apoptotic cells, mitotic slippage and finally an increase in 'classical' apoptotic cells. Exposure to winter-PM10 induced only a slight effect which may be due to the presence of PM2.5 in this fraction while pure combustion particles failed to disturb mitosis. Fewer cells expressing the mitosis marker phospho-histone H3 compared to cells with condensed chromosomes, suggest that PM2.5 induced premature mitosis. PM2.5 was internalized into the cells and often localized in laminar organelles, although particles without apparent plasma membrane covering were also seen. In PM-containing cells mitochondria and lysosomes were often damaged, and in mitotic cells fragmented chromosomes often appeared. PM2.5 induced DNA strands breaks and triggered a DNA-damage response characterized by increased phosphorylation of ATM, Chk2 and H2AX; as well as induced a marked increase in expression of the aryl hydrocarbon receptor (AhR)-regulated genes, CYP1A1, CYP1B1 and AhRR. Furthermore, some disturbance of the organization of microtubules was indicated. It is hypothesized that the induced mitotic arrest and following cell death was due to a premature chromosome condensation caused by a combination of DNA, mitochondrial and spindle damage.

  4. Spindle Cell Hemangioendothelioma of the Temporal Muscle Resected with Zygomatic Osteotomy: A Case Report of an Unusual Intramuscular Lesion Mimicking Sarcoma

    Directory of Open Access Journals (Sweden)

    Tomohiro Minagawa

    2011-01-01

    Full Text Available Spindle cell hemangioendothelioma (SCH was originally described by Weiss and Enzinger (1986 as a low-grade angiosarcoma resembling both cavernous hemangioma and Kaposi's sarcoma. Recent studies suggest that SCH is a benign neoplasm or reactive lesion accompanying a congenital or acquired vascular malformation. Most SCHs present as one or more nodules affecting the dermis or subcutis of the distal extremities. Few reports describe SCH of the head and neck region; even fewer note intramuscular SCH. Here, we describe a case of SCH involving the temporal muscle mimicking soft tissue sarcoma, who had a successful surgical treatment with a coronal approach and zygomatic osteotomy.

  5. Wnt-10b promotes differentiation of skin epithelial cells in vitro

    International Nuclear Information System (INIS)

    Ouji, Yukiteru; Yoshikawa, Masahide; Shiroi, Akira; Ishizaka, Shigeaki

    2006-01-01

    To evaluate the role of Wnt-10b in epithelial differentiation, we investigated the effects of Wnt-10b on adult mouse-derived primary skin epithelial cells (MPSEC). Recombinant Wnt-10b protein (rWnt-10b) was prepared using a gene engineering technique and MPSEC were cultured in its presence, which resulted in morphological changes from cuboidal to spindle-shaped and inhibited their proliferation. Further, involvement of the canonical Wnt signal pathway was also observed. MPSEC treated with rWnt-10b showed characteristics of the hair shaft and inner root sheath of the hair follicle, in results of Ayoub Shklar staining and immunocytochemistry. Further, the cells expressed mRNA for differentiated epithelial cells, including keratin 1, keratin 2, loricrin, mHa5, and mHb5, in association with a decreased expression of the basal cell marker keratin 5. These results suggest that Wnt-10b promotes the differentiation of MPSEC

  6. Regulators of Tfh cell differentiation

    Directory of Open Access Journals (Sweden)

    Gajendra Motiram Jogdand

    2016-11-01

    Full Text Available The follicular helper T (Tfh cells help is critical for activation of B cells, antibody class switching and germinal center formation. The Tfh cells are characterized by the expression of CXCR5, ICOS, PD-1, Bcl-6, and IL-21. They are involved in clearing infections and are adversely linked with autoimmune diseases and also have a role in viral replication as well as clearance. Tfh cells are generated from naïve CD4 T cells with sequential steps involving cytokine signaling (IL-21, IL-6, IL-12, activin A, migration and positioning in the germinal center by CXCR5, surface receptors (ICOS/ICOSL, SAP/SLAM as well as transcription factor (Bcl-6, c-Maf, STAT3 signaling and repressor miR155. On the other hand Tfh generation is negatively regulated at specific steps of Tfh generation by specific cytokine (IL-2, IL-7, surface receptor (PD-1, CTLA-4, transcription factors Blimp-1, STAT5, T-bet, KLF-2 signaling and repressor miR 146a. Interestingly, miR 17-92 and FOXO1 acts as a positive as well as a negative regulator of Tfh differentiation depending on the time of expression and disease specificity. Tfh cells are also generated from the conversion of other effector T cells as exemplified by Th1 cells converting into Tfh during viral infection. The mechanistic details of effector T cells conversion into Tfh are yet to be clear. To manipulate Tfh cells for therapeutic implication and or for effective vaccination strategies, it is important to know positive and negative regulators of Tfh generation. Hence, in this review we have highlighted and interlinked molecular signaling from cytokines, surface receptors, transcription factors, ubiquitin Ligase and miRNA as positive and negative regulators for Tfh differentiation.

  7. Spatial signals link exit from mitosis to spindle position.

    Science.gov (United States)

    Falk, Jill Elaine; Tsuchiya, Dai; Verdaasdonk, Jolien; Lacefield, Soni; Bloom, Kerry; Amon, Angelika

    2016-05-11

    In budding yeast, if the spindle becomes mispositioned, cells prevent exit from mitosis by inhibiting the mitotic exit network (MEN). The MEN is a signaling cascade that localizes to spindle pole bodies (SPBs) and activates the phosphatase Cdc14. There are two competing models that explain MEN regulation by spindle position. In the 'zone model', exit from mitosis occurs when a MEN-bearing SPB enters the bud. The 'cMT-bud neck model' posits that cytoplasmic microtubule (cMT)-bud neck interactions prevent MEN activity. Here we find that 1) eliminating cMT- bud neck interactions does not trigger exit from mitosis and 2) loss of these interactions does not precede Cdc14 activation. Furthermore, using binucleate cells, we show that exit from mitosis occurs when one SPB enters the bud despite the presence of a mispositioned spindle. We conclude that exit from mitosis is triggered by a correctly positioned spindle rather than inhibited by improper spindle position.

  8. The fission yeast spindle orientation checkpoint: a model that generates tension?

    Science.gov (United States)

    Gachet, Yannick; Reyes, Céline; Goldstone, Sherilyn; Tournier, Sylvie

    2006-10-15

    In all eukaryotes, the alignment of the mitotic spindle with the axis of cell polarity is essential for accurate chromosome segregation as well as for the establishment of cell fate, and thus morphogenesis, during development. Studies in invertebrates, higher eukaryotes and yeast suggest that astral microtubules interact with the cell cortex to position the spindle. These microtubules are thought to impose pushing or pulling forces on the spindle poles to affect the rotation or movement of the spindle. In the fission yeast model, where cell division is symmetrical, spindle rotation is dependent on the interaction of astral microtubules with the cortical actin cytoskeleton. In these cells, a bub1-dependent mitotic checkpoint, the spindle orientation checkpoint (SOC), is activated when the spindles fail to align with the cell polarity axis. In this paper we review the mechanism that orientates the spindle during mitosis in fission yeast, and discuss the consequences of misorientation on metaphase progression. Copyright 2006 John Wiley & Sons, Ltd.

  9. Inscuteable Regulates the Pins-Mud Spindle Orientation Pathway

    Science.gov (United States)

    Mauser, Jonathon F.; Prehoda, Kenneth E.

    2012-01-01

    During asymmetric cell division, alignment of the mitotic spindle with the cell polarity axis ensures that the cleavage furrow separates fate determinants into distinct daughter cells. The protein Inscuteable (Insc) is thought to link cell polarity and spindle positioning in diverse systems by binding the polarity protein Bazooka (Baz; aka Par-3) and the spindle orienting protein Partner of Inscuteable (Pins; mPins or LGN in mammals). Here we investigate the mechanism of spindle orientation by the Insc-Pins complex. Previously, we defined two Pins spindle orientation pathways: a complex with Mushroom body defect (Mud; NuMA in mammals) is required for full activity, whereas binding to Discs large (Dlg) is sufficient for partial activity. In the current study, we have examined the role of Inscuteable in mediating downstream Pins-mediated spindle orientation pathways. We find that the Insc-Pins complex requires Gαi for partial activity and that the complex specifically recruits Dlg but not Mud. In vitro competition experiments revealed that Insc and Mud compete for binding to the Pins TPR motifs, while Dlg can form a ternary complex with Insc-Pins. Our results suggest that Insc does not passively couple polarity and spindle orientation but preferentially inhibits the Mud pathway, while allowing the Dlg pathway to remain active. Insc-regulated complex assembly may ensure that the spindle is attached to the cortex (via Dlg) before activation of spindle pulling forces by Dynein/Dynactin (via Mud). PMID:22253744

  10. Regulation of cortical contractility and spindle positioning by the protein phosphatase 6 PPH-6 in one-cell stage C. elegans embryos

    Science.gov (United States)

    Afshar, Katayoun; Werner, Michael E.; Tse, Yu Chung; Glotzer, Michael; Gönczy, Pierre

    2010-01-01

    Modulation of the microtubule and the actin cytoskeleton is crucial for proper cell division. Protein phosphorylation is known to be an important regulatory mechanism modulating these cytoskeletal networks. By contrast, there is a relative paucity of information regarding how protein phosphatases contribute to such modulation. Here, we characterize the requirements for protein phosphatase PPH-6 and its associated subunit SAPS-1 in one-cell stage C. elegans embryos. We establish that the complex of PPH-6 and SAPS-1 (PPH-6/SAPS-1) is required for contractility of the actomyosin network and proper spindle positioning. Our analysis demonstrates that PPH-6/SAPS-1 regulates the organization of cortical non-muscle myosin II (NMY-2). Accordingly, we uncover that PPH-6/SAPS-1 contributes to cytokinesis by stimulating actomyosin contractility. Furthermore, we demonstrate that PPH-6/SAPS-1 is required for the proper generation of pulling forces on spindle poles during anaphase. Our results indicate that this requirement is distinct from the role in organizing the cortical actomyosin network. Instead, we uncover that PPH-6/SAPS-1 contributes to the cortical localization of two positive regulators of pulling forces, GPR-1/2 and LIN-5. Our findings provide the first insights into the role of a member of the PP6 family of phosphatases in metazoan development. PMID:20040490

  11. Apc bridges Wnt/{beta}-catenin and BMP signaling during osteoblast differentiation of KS483 cells

    Energy Technology Data Exchange (ETDEWEB)

    Miclea, Razvan L., E-mail: R.L.Miclea@lumc.nl [Department of Pediatrics, Leiden University Medical Centre (LUMC), Leiden (Netherlands); Horst, Geertje van der, E-mail: G.van_der_Horst@lumc.nl [Department of Urology, LUMC, Leiden (Netherlands); Robanus-Maandag, Els C., E-mail: E.C.Robanus@lumc.nl [Department of Human Genetics, LUMC, Leiden (Netherlands); Loewik, Clemens W.G.M., E-mail: C.W.G.M.Lowik@lumc.nl [Department of Endocrinology and Metabolic Diseases, LUMC, Leiden (Netherlands); Oostdijk, Wilma, E-mail: W.Oostdijk@lumc.nl [Department of Pediatrics, Leiden University Medical Centre (LUMC), Leiden (Netherlands); Wit, Jan M., E-mail: J.M.Wit@lumc.nl [Department of Pediatrics, Leiden University Medical Centre (LUMC), Leiden (Netherlands); Karperien, Marcel, E-mail: H.B.J.Karperien@tnw.utwente.nl [MIRA Institute for Biomedical Technology and Technical Medicine, Department of Tissue Regeneration, University of Twente, Zuidhorst Room ZH 144, Drienerlolaan 5, 7522 NB Enschede (Netherlands)

    2011-06-10

    The canonical Wnt signaling pathway influences the differentiation of mesenchymal cell lineages in a quantitative and qualitative fashion depending on the dose of {beta}-catenin signaling. Adenomatous polyposis coli (Apc) is the critical intracellular regulator of {beta}-catenin turnover. To better understand the molecular mechanisms underlying the role of Apc in regulating the differentiation capacity of skeletal progenitor cells, we have knocked down Apc in the murine mesenchymal stem cell-like KS483 cells by stable expression of Apc-specific small interfering RNA. In routine culture, KSFrt-Apc{sub si} cells displayed a mesenchymal-like spindle shape morphology, exhibited markedly decreased proliferation and increased apoptosis. Apc knockdown resulted in upregulation of the Wnt/{beta}-catenin and the BMP/Smad signaling pathways, but osteogenic differentiation was completely inhibited. This effect could be rescued by adding high concentrations of BMP-7 to the differentiation medium. Furthermore, KSFrt-Apc{sub si} cells showed no potential to differentiate into chondrocytes or adipocytes. These results demonstrate that Apc is essential for the proliferation, survival and differentiation of KS483 cells. Apc knockdown blocks the osteogenic differentiation of skeletal progenitor cells, a process that can be overruled by high BMP signaling.

  12. Carcinoma fusocelular de cavidad oral: Revisión de 9 casos Spindle cell carcinoma of the oral cavity: A review of 9 cases

    Directory of Open Access Journals (Sweden)

    G. Gómez Oliveira

    2006-02-01

    Full Text Available El carcinoma fusocelular es una variedad maligna y poco frecuente del carcinoma de células escamosas. Es una tumoración constituida por una doble proliferación celular: una sarcomatosa de células fusocelulares y otra carcinomatosa de células epiteliales. Aunque puede afectar a cualquier parte del organismo, es más frecuente encontrarla en vías aerodigestivas superiores. Afecta con mayor frecuencia a varones entre la 6ª y 7ª décadas de la vida. Tiene un comportamiento agresivo con tendencia a la recurrencia. El alcohol y tabaco han sido identificados como los factores de riesgo más importantes. Su diagnóstico histológico es complicado y muchas veces es necesario recurrir a técnicas de inmunohistoquímica y al uso del microscopio electrónico. En la actualidad, se le atribuye un origen epitelial. El objetivo de este trabajo es presentar una revisión de 9 casos de carcinoma fusocelular localizados en cavidad oral recogidos en nuestro servicio entre los años 1985 a 2004, describiendo su comportamiento clínico y tratando de comprender la patogenia de esta controvertida estirpe tumoral.Spindle cell carcinoma is a malignant and rare variant of squamous cell carcinoma. The histological pattern is composed of a double cell proliferation: a sarcomatous component made up of spindle-shaped cells and a carcinomatous component made up of epithelial cells. Nearly all the anatomy of the body can be affected by these tumors although the most common location is the upper aerodigestive tract. With regard to sex distribution, it is more frequent in males than in females in their sixth and seventh decades of life. Its behavior is aggressive and it tends to recur after treatment. The most important risk factors are alcohol and tobacco. The histological diagnosis is complicated, so immunohistochemical techniques and the use of electron microscopy are usually necessary. Nowadays, its epithelial origin is accepted. The aim of this article is to report a

  13. Nuclear Mechanics and Stem Cell Differentiation.

    Science.gov (United States)

    Mao, Xinjian; Gavara, Nuria; Song, Guanbin

    2015-12-01

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

  14. Characterization of a putative spindle assembly checkpoint kinase Mps1, suggests its involvement in cell division, morphogenesis and oxidative stress tolerance in Candida albicans.

    Directory of Open Access Journals (Sweden)

    Mohan Kamthan

    Full Text Available In Saccharomyces cerevisiae MPS1 is one of the major protein kinase that governs the spindle checkpoint pathway. The S. cerevisiae structural homolog of opportunistic pathogen Candida albicans CaMPS1, is indispensable for the cell viability. The essentiality of Mps1 was confirmed by Homozygote Trisome test. To determine its biological function in this pathogen conditional mutant was generated through regulatable MET3 promoter. Examination of heterozygous and conditional (+Met/Cys mps1 mutants revealed a mitosis specific arrest phenotype, where mutants showed large buds with undivided nuclei. Flowcytometry analysis revealed abnormal ploidy levels in mps1 mutant. In presence of anti-microtubule drug Nocodazole, mps1 mutant showed a dramatic loss of viability suggesting a role of Mps1 in Spindle Assembly Checkpoint (SAC activation. These mutants were also defective in microtubule organization. Moreover, heterozygous mutant showed defective in-vitro yeast to hyphae morphological transition. Growth defect in heterozygous mutant suggest haploinsufficiency of this gene. qRT PCR analysis showed around 3 fold upregulation of MPS1 in presence of serum. This expression of MPS1 is dependent on Efg1 and is independent of other hyphal regulators like Ras1 and Tpk2. Furthermore, mps1 mutants were also sensitive to oxidative stress. Heterozygous mps1 mutant did not undergo morphological transition and showed 5-Fold reduction in colony forming units in response to macrophage. Thus, the vital checkpoint kinase, Mps1 besides cell division also has a role in morphogenesis and oxidative stress tolerance, in this pathogenic fungus.

  15. Can bone marrow differentiate into renal cells?

    Science.gov (United States)

    Imai, Enyu; Ito, Takahito

    2002-10-01

    A considerable plasticity of adult stem cells has been confirmed in a wide variety of tissues. In particular, the pluripotency of bone marrow-derived stem cells may influence the regeneration of injured tissues and may provide novel avenues in regenerative medicine. Bone marrow contains at least hematopoietic and mesenchymal stem cells, and both can differentiate into a wide range of differentiated cells. Side population (SP) cells, which are originally defined in bone marrow cells by high efflux of DNA-binding dye, seem to be a new class of multipotent stem cells. Irrespective of the approach used to obtain stem cells, the fates of marrow-derived cells following bone marrow transplantation can be traced by labeling donor cells with green fluorescence protein or by identifying donor Y chromosome in female recipients. So far, bone marrow-derived cells have been reported to differentiate into renal cells, including mesangial cells, endothelial cells, podocytes, and tubular cells in the kidney, although controversy exists. Further studies are required to address this issue. Cell therapy will be promising when we learn to control stem cells such as bone marrow-derived stem cells, embryonic stem cells, and resident stem cells in the kidney. Identification of factors that support stem cells or promote their differentiation should provide a relevant step towards cell therapy.

  16. Phyllanthus emblica Fruit Extract Activates Spindle Assembly Checkpoint, Prevents Mitotic Aberrations and Genomic Instability in Human Colon Epithelial NCM460 Cells

    Directory of Open Access Journals (Sweden)

    Xihan Guo

    2016-09-01

    Full Text Available The fruit of Phyllanthus emblica Linn. (PE has been widely consumed as a functional food and folk medicine in Southeast Asia due to its remarkable nutritional and pharmacological effects. Previous research showed PE delays mitotic progress and increases genomic instability (GIN in human colorectal cancer cells. This study aimed to investigate the similar effects of PE by the biomarkers related to spindle assembly checkpoint (SAC, mitotic aberrations and GIN in human NCM460 normal colon epithelial cells. Cells were treated with PE and harvested differently according to the biomarkers observed. Frequencies of micronuclei (MN, nucleoplasmic bridge (NPB and nuclear bud (NB in cytokinesis-block micronucleus assay were used as indicators of GIN. Mitotic aberrations were assessed by the biomarkers of chromosome misalignment, multipolar division, chromosome lagging and chromatin bridge. SAC activity was determined by anaphase-to- metaphase ratio (AMR and the expression of core SAC gene budding uninhibited by benzimidazoles related 1 (BubR1. Compared with the control, PE-treated cells showed (1 decreased incidences of MN, NPB and NB (p < 0.01; (2 decreased frequencies of all mitotic aberration biomarkers (p < 0.01; and (3 decreased AMR (p < 0.01 and increased BubR1 expression (p < 0.001. The results revealed PE has the potential to protect human normal colon epithelial cells from mitotic and genomic damages partially by enhancing the function of SAC.

  17. A spindle pole antigen gene MoSPA2 is important for polar cell growth of vegetative hyphae and conidia, but is dispensable for pathogenicity in Magnaporthe oryzae.

    Science.gov (United States)

    Li, Chao; Yang, Jun; Zhou, Wei; Chen, Xiao-Lin; Huang, Jin-Guang; Cheng, Zhi-Hua; Zhao, Wen-Sheng; Zhang, Yan; Peng, You-Liang

    2014-11-01

    Spa2 is an important component of the multiprotein complex polarisome, which is involved in the establishment, maintenance, termination of polarized cell growth and is important for defining tip growth of filamentous fungi. In this study, we isolated an insertional mutant of the rice blast fungus Magnaporthe oryzae that formed smaller colony and conidia compared with the wild type. In the mutant, a spindle pole antigen gene MoSPA2 was disrupted by the integration of an exogenous plasmid. Targeted gene deletion and complementation assays demonstrated the gene disruption was responsible for the defects of the insertional mutant. Interestingly, the MoSpa2-GFP fusion protein was found to accumulate as a spot at hyphal tips, septa of hyphae and conidial tip cells where germ tubes are usually produced, but not in appressoria, infection hyphae or at the septa of conidia. Furthermore, the deletion mutants of MoSPA2 exhibited slower hyphal tip growth, more hyphal branches, and smaller size of conidial tip cells. However, MoSPA2 is not required for plant infection. These results indicate that MoSPA2 is required for vegetative hyphal growth and maintaining conidium morphology and that spotted accumulation of MoSpa2 is important for its functions during cell polar growth.

  18. Sleep spindles predict stress-related increases in sleep disturbances

    Directory of Open Access Journals (Sweden)

    Thien Thanh eDang-Vu

    2015-02-01

    Full Text Available Background and Aim: Predisposing factors place certain individuals at higher risk for insomnia, especially in the presence of precipitating conditions such as stressful life events. Sleep spindles have been shown to play an important role in the preservation of sleep continuity. Lower spindle density might thus constitute an objective predisposing factor for sleep reactivity to stress. The aim of this study was therefore to evaluate the relationship between baseline sleep spindle density and the prospective change in insomnia symptoms in response to a standardized academic stressor. Methods: 12 healthy students had a polysomnography (PSG recording during a period of lower stress at the beginning of the academic semester, along with an assessment of insomnia complaints using the Insomnia Severity Index (ISI. They completed a second ISI assessment at the end of the semester, a period coinciding with the week prior to final examinations and thus higher stress. Spindle density, amplitude, duration and frequency, as well as sigma power were computed from C4-O2 electroencephalography (EEG derivation during stages N2-N3 of non-rapid-eye-movement (NREM sleep, across the whole night and for each NREM sleep period. To test for the relationship between spindle density and changes in insomnia symptoms in response to academic stress, spindle measurements at baseline were correlated with changes in ISI across the academic semester.Results: Spindle density (as well as spindle amplitude and sigma power, particularly during the first NREM sleep period, negatively correlated with changes in ISI (p < 0.05. Conclusion: Lower spindle activity, especially at the beginning of the night, prospectively predicted larger increases in insomnia symptoms in response to stress. This result indicates that individual differences in sleep spindle activity contribute to the differential vulnerability to sleep disturbances in the face of precipitating factors.

  19. Malignant myoepithelial cells are associated with the differentiated papillary structure and metastatic ability of a syngeneic murine mammary adenocarcinoma model

    International Nuclear Information System (INIS)

    Bumaschny, Viviana; Urtreger, Alejandro; Diament, Miriam; Krasnapolski, Martín; Fiszman, Gabriel; Klein, Slobodanka; Joffé, Elisa Bal de Kier

    2004-01-01

    The normal duct and lobular system of the mammary gland is lined with luminal and myoepithelial cell types. Although evidence suggests that myoepithelial cells might suppress tumor growth, invasion and angiogenesis, their role remains a major enigma in breast cancer biology and few models are currently available for exploring their influence. Several years ago a spontaneous transplantable mammary adenocarcinoma (M38) arose in our BALB/c colony; it contains a malignant myoepithelial cell component and is able to metastasize to draining lymph nodes and lung. To characterize this tumor further, primary M38 cultures were established. The low-passage LM38-LP subline contained two main cell components up to the 30th subculture, whereas the higher passage LM38-HP subline was mainly composed of small spindle-shaped cells. In addition, a large spindle cell clone (LM38-D2) was established by dilutional cloning of the low-passage MM38-LP cells. These cell lines were studied by immunocytochemistry, electron microscopy and ploidy, and syngeneic mice were inoculated subcutaneously and intravenously with the different cell lines, either singly or combined to establish their tumorigenic and metastatic capacity. The two subpopulations of LM38-LP cultures were characterized as luminal and myoepithelium-like cells, whereas LM38-HP was mainly composed of small, spindle-shaped epithelial cells and LM38-D2 contained only large myoepithelial cells. All of them were tumorigenic when inoculated into syngeneic mice, but only LM38-LP cultures containing both conserved luminal and myoepithelial malignant cells developed aggressive papillary adenocarcinomas that spread to lung and regional lymph nodes. The differentiated histopathology and metastatic ability of the spontaneous transplantable M38 murine mammary tumor is associated with the presence and/or interaction of both luminal and myoepithelial tumor cell types

  20. Transcriptome changes during intestinal cell differentiation

    DEFF Research Database (Denmark)

    Tadjali, Mehrdad; Seidelin, Jakob B; Olsen, Jørgen Lillelund

    2002-01-01

    The expression of 18149 genes have been analysed during the differentiation of the human intestinal cell line Caco-2. cDNA probes from undifferentiated and differentiated Caco-2 cells were separately hybridised to EST DNAs spotted in an array on a nylon membrane. A remarkable change in the transc...

  1. In vitro differentiation of human umbilical cord blood mesenchymal ...

    African Journals Online (AJOL)

    Mesenchymal stem cells (MSCs) were isolated by gradient density centrifugation from umbilical cord blood. Spindle-shaped adherent cells were permitted to grow to 70% confluence in primary culture media which was reached by day 12. Induction of differentiation started by culturing cells with differentiation medium ...

  2. The Making of SPINdle

    Science.gov (United States)

    Lam, Ho-Pun; Governatori, Guido

    We present the design and implementation of SPINdle - an open source Java based defeasible logic reasoner capable to perform efficient and scalable reasoning on defeasible logic theories (including theories with over 1 million rules). The implementation covers both the standard and modal extensions to defeasible logics. It can be used as a standalone theory prover and can be embedded into any applications as a defeasible logic rule engine. It allows users or agents to issues queries, on a given knowledge base or a theory generated on the fly by other applications, and automatically produces the conclusions of its consequences. The theory can also be represented using XML.

  3. Valve spindle gland

    International Nuclear Information System (INIS)

    Burda, Z.; Harazim, A.; Kerlin, K.

    1979-01-01

    A gland is proposed of the valve spindle designed for radioactive or otherwise harmful media, such as in nuclear power plant primary circuits. The gland is installed in the valve cover and consists of a primary and a secondary part and of a gland case partitioning the gland space into two chambers. The bottom face of the gland case is provided with a double-sided collar for controlling the elements of the bottom primary gland while the top face is provided with a removable flange. (M.S.)

  4. Wnt-10b secreted from lymphocytes promotes differentiation of skin epithelial cells

    International Nuclear Information System (INIS)

    Ouji, Yukiteru; Yoshikawa, Masahide; Shiroi, Akira; Ishizaka, Shigeaki

    2006-01-01

    Wnt-10b was originally isolated from lymphoid tissue and is known to be involved in a wide range of biological actions, while recently it was found to be expressed early in the development of hair follicles. However, few studies have been conducted concerning the role of Wnt-10b with the differentiation of skin epithelial cells. To evaluate its role in epithelial differentiation, we purified Wnt-10b from the supernatant of a concanavalin A-stimulated lymphocyte culture using an affinity column and investigated its effects on the differentiation of adult mouse-derived primary skin epithelial cells (MPSEC). MPSEC cultured with Wnt-10b showed morphological changes from cuboidal to spindle-shaped with inhibited proliferation, and also obtained characteristics of the hair shaft and inner root sheath of the hair follicle, represented by red-colored Ayoub Shklar staining, and reactions to AE-13 and AE-15 as seen with immunocytology. Further, RT-PCR analysis demonstrated the expression of mRNA for keratin 1, keratin 2, loricrin, mHa5, and mHb5, in association with a decreased expression of the basal cell marker keratin 5, in Wnt-10b-treated MPSEC. In addition, involvement of the canonical Wnt signal pathway was demonstrated by a TCF reporter (pTOPFLASH) assay. These results suggest that Wnt-10b promotes the differentiation of MPSEC and may play an important role in hair follicle development by promoting differentiation of epithelial cells

  5. Cancer stem cells and differentiation therapy.

    Science.gov (United States)

    Jin, Xiong; Jin, Xun; Kim, Hyunggee

    2017-10-01

    Cancer stem cells can generate tumors from only a small number of cells, whereas differentiated cancer cells cannot. The prominent feature of cancer stem cells is its ability to self-renew and differentiate into multiple types of cancer cells. Cancer stem cells have several distinct tumorigenic abilities, including stem cell signal transduction, tumorigenicity, metastasis, and resistance to anticancer drugs, which are regulated by genetic or epigenetic changes. Like normal adult stem cells involved in various developmental processes and tissue homeostasis, cancer stem cells maintain their self-renewal capacity by activating multiple stem cell signaling pathways and inhibiting differentiation signaling pathways during cancer initiation and progression. Recently, many studies have focused on targeting cancer stem cells to eradicate malignancies by regulating stem cell signaling pathways, and products of some of these strategies are in preclinical and clinical trials. In this review, we describe the crucial features of cancer stem cells related to tumor relapse and drug resistance, as well as the new therapeutic strategy to target cancer stem cells named "differentiation therapy."

  6. DNA repair in murine embryonic stem cells and differentiated cells

    International Nuclear Information System (INIS)

    Tichy, Elisia D.; Stambrook, Peter J.

    2008-01-01

    Embryonic stem (ES) cells are rapidly proliferating, self-renewing cells that have the capacity to differentiate into all three germ layers to form the embryo proper. Since these cells are critical for embryo formation, they must have robust prophylactic mechanisms to ensure that their genomic integrity is preserved. Indeed, several studies have suggested that ES cells are hypersensitive to DNA damaging agents and readily undergo apoptosis to eliminate damaged cells from the population. Other evidence suggests that DNA damage can cause premature differentiation in these cells. Several laboratories have also begun to investigate the role of DNA repair in the maintenance of ES cell genomic integrity. It does appear that ES cells differ in their capacity to repair damaged DNA compared to differentiated cells. This minireview focuses on repair mechanisms ES cells may use to help preserve genomic integrity and compares available data regarding these mechanisms with those utilized by differentiated cells

  7. Intercentrosomal angular separation during mitosis plays a crucial role for maintaining spindle stability

    Science.gov (United States)

    Sutradhar, S.; Basu, S.; Paul, R.

    2015-10-01

    Cell division through proper spindle formation is one of the key puzzles in cell biology. In most mammalian cells, chromosomes spontaneously arrange to achieve a stable bipolar spindle during metaphase which eventually ensures proper segregation of the DNA into the daughter cells. In this paper, we present a robust three-dimensional mechanistic model to investigate the formation and maintenance of a bipolar mitotic spindle in mammalian cells under different physiological constraints. Using realistic parameters, we test spindle viability by measuring the spindle length and studying the chromosomal configuration. The model strikingly predicts a feature of the spindle instability arising from the insufficient intercentrosomal angular separation and impaired sliding of the interpolar microtubules. In addition, our model successfully reproduces chromosomal patterns observed in mammalian cells, when activity of different motor proteins is perturbed.

  8. Transcriptome changes during intestinal cell differentiation

    DEFF Research Database (Denmark)

    Tadjali, Mehrdad; Seidelin, Jakob B; Olsen, Jørgen

    2002-01-01

    The expression of 18149 genes have been analysed during the differentiation of the human intestinal cell line Caco-2. cDNA probes from undifferentiated and differentiated Caco-2 cells were separately hybridised to EST DNAs spotted in an array on a nylon membrane. A remarkable change in the transc......The expression of 18149 genes have been analysed during the differentiation of the human intestinal cell line Caco-2. cDNA probes from undifferentiated and differentiated Caco-2 cells were separately hybridised to EST DNAs spotted in an array on a nylon membrane. A remarkable change...... cells by performing reverse transcriptase-polymerase chain reaction on RNA extracted from laser dissected intestinal crypt and villi. In a screen of eight transcripts one - SART3 - was identified as a marker for human colonic crypts....

  9. Chromatin in embryonic stem cell neuronal differentiation.

    Science.gov (United States)

    Meshorer, E

    2007-03-01

    Chromatin, the basic regulatory unit of the eukaryotic genetic material, is controlled by epigenetic mechanisms including histone modifications, histone variants, DNA methylation and chromatin remodeling. Cellular differentiation involves large changes in gene expression concomitant with alterations in genome organization and chromatin structure. Such changes are particularly evident in self-renewing pluripotent embryonic stem cells, which begin, in terms of cell fate, as a tabula rasa, and through the process of differentiation, acquire distinct identities. Here I describe the changes in chromatin that accompany neuronal differentiation, particularly of embryonic stem cells, and discuss how chromatin serves as the master regulator of cellular destiny.

  10. Human Pluripotent Stem Cell Differentiation into Functional Epicardial Progenitor Cells

    NARCIS (Netherlands)

    Guadix, Juan Antonio; Orlova, Valeria V.; Giacomelli, Elisa; Bellin, Milena; Ribeiro, Marcelo C.; Mummery, Christine L.; Pérez-Pomares, José M.; Passier, Robert

    2017-01-01

    Human pluripotent stem cells (hPSCs) are widely used to study cardiovascular cell differentiation and function. Here, we induced differentiation of hPSCs (both embryonic and induced) to proepicardial/epicardial progenitor cells that cover the heart during development. Addition of retinoic acid (RA)

  11. Mitotic Spindle Asymmetry: A Wnt/PCP-Regulated Mechanism Generating Asymmetrical Division in Cortical Precursors

    Directory of Open Access Journals (Sweden)

    Delphine Delaunay

    2014-01-01

    Full Text Available The regulation of asymmetric cell division (ACD during corticogenesis is incompletely understood. We document that spindle-size asymmetry (SSA between the two poles occurs during corticogenesis and parallels ACD. SSA appears at metaphase and is maintained throughout division, and we show it is necessary for proper neurogenesis. Imaging of spindle behavior and division outcome reveals that neurons preferentially arise from the larger-spindle pole. Mechanistically, SSA magnitude is controlled by Wnt7a and Vangl2, both members of the Wnt/planar cell polarity (PCP-signaling pathway, and relayed to the cell cortex by P-ERM proteins. In vivo, Vangl2 and P-ERM downregulation promotes early cell-cycle exit and prevents the proper generation of late-born neurons. Thus, SSA is a core component of ACD that is conserved in invertebrates and vertebrates and plays a key role in the tight spatiotemporal control of self-renewal and differentiation during mammalian corticogenesis.

  12. Control of differentiation of melanoma cells

    International Nuclear Information System (INIS)

    Eguchi, Goro

    1980-01-01

    To develop the method to induce the appearance of differentiation in amelanotic melanoma, experimental control of differentiation in B-16 melanoma cells of mice was discussed. Human melanoma cells and yellow melanin pigment cells useful for a fundamental study of radiotherapy for cancer were cultured and were differentiated into some lines. Melanotic B-16 cells and amelanotic B-16 cells were irradiated with thermal neutron (neutron: 2.7 x 10 12 , γ-dose: 32.3 rad) after they were cultured in culture solution containing 10 γ/ml of 10 B-dopa for 13 hours. A fine structure 5 hours after the irradiation in one of 5 experimental cases showed aggregated disintegration of melanin pigment particles, markedly deformed and fragmentized nucleus, and structural changes in cell membrane. (Tsunoda, M.)

  13. Nucleotide excision repair in differentiated cells

    Energy Technology Data Exchange (ETDEWEB)

    Wees, Caroline van der [Department of Toxicogenetics, Leiden University Medical Center, Leiden (Netherlands); Department of Cardiology, Leiden University Medical Center, Leiden (Netherlands); Jansen, Jacob [Department of Toxicogenetics, Leiden University Medical Center, Leiden (Netherlands); Vrieling, Harry [Department of Toxicogenetics, Leiden University Medical Center, Leiden (Netherlands); Laarse, Arnoud van der [Department of Cardiology, Leiden University Medical Center, Leiden (Netherlands); Zeeland, Albert van [Department of Toxicogenetics, Leiden University Medical Center, Leiden (Netherlands); Mullenders, Leon [Department of Toxicogenetics, Leiden University Medical Center, Leiden (Netherlands)]. E-mail: l.mullenders@lumc.nl

    2007-01-03

    Nucleotide excision repair (NER) is the principal pathway for the removal of a wide range of DNA helix-distorting lesions and operates via two NER subpathways, i.e. global genome repair (GGR) and transcription-coupled repair (TCR). Although detailed information is available on expression and efficiency of NER in established mammalian cell lines, little is known about the expression of NER pathways in (terminally) differentiated cells. The majority of studies in differentiated cells have focused on repair of UV-induced cyclobutane pyrimidine dimers (CPD) and 6-4-photoproducts (6-4PP) because of the high frequency of photolesions at low level of toxicity and availability of sensitive technologies to determine photolesions in defined regions of the genome. The picture that emerges from these studies is blurred and rather complex. Fibroblasts and terminally differentiated myocytes of the rat heart display equally efficient GGR of 6-4PP but poor repair of CPD due to the absence of p48 expression. This repair phenotype is clearly different from human terminal differentiated neurons. Furthermore, both cell types were found to carry out TCR of CPD, thus mimicking the repair phenotype of established rodent cell lines. In contrast, in intact rat spermatogenic cells repair was very inefficient at the genome overall level and in transcriptionally active genes indicating that GGR and TCR are non-functional. Also, non-differentiated mouse embryonic stem (ES) cells exhibit low levels of NER after UV irradiation. However, the mechanisms that lead to low NER activity are clearly different: in differentiated spermatogenic cells differences in chromatin compaction and sequestering of NER proteins may underlie the lack of NER activity in pre-meiotic cells, whereas in non-differentiated ES cells NER is impaired by a strong apoptotic response.

  14. Human Pluripotent Stem Cell Differentiation into Functional Epicardial Progenitor Cells

    Directory of Open Access Journals (Sweden)

    Juan Antonio Guadix

    2017-12-01

    Full Text Available Summary: Human pluripotent stem cells (hPSCs are widely used to study cardiovascular cell differentiation and function. Here, we induced differentiation of hPSCs (both embryonic and induced to proepicardial/epicardial progenitor cells that cover the heart during development. Addition of retinoic acid (RA and bone morphogenetic protein 4 (BMP4 promoted expression of the mesodermal marker PDGFRα, upregulated characteristic (proepicardial progenitor cell genes, and downregulated transcription of myocardial genes. We confirmed the (proepicardial-like properties of these cells using in vitro co-culture assays and in ovo grafting of hPSC-epicardial cells into chick embryos. Our data show that RA + BMP4-treated hPSCs differentiate into (proepicardial-like cells displaying functional properties (adhesion and spreading over the myocardium of their in vivo counterpart. The results extend evidence that hPSCs are an excellent model to study (proepicardial differentiation into cardiovascular cells in human development and evaluate their potential for cardiac regeneration. : The authors have shown that hPSCs can be instructed in vitro to differentiate into a specific cardiac embryonic progenitor cell population called the proepicardium. Proepicardial cells are required for normal formation of the heart during development and might contribute to the development of cell-based therapies for heart repair. Keywords: human pluripotent stem cells, proepicardium, progenitor cells, cardiovascular, differentiation

  15. Nanotopographical Control of Stem Cell Differentiation

    Directory of Open Access Journals (Sweden)

    Laura E. McNamara

    2010-01-01

    Full Text Available Stem cells have the capacity to differentiate into various lineages, and the ability to reliably direct stem cell fate determination would have tremendous potential for basic research and clinical therapy. Nanotopography provides a useful tool for guiding differentiation, as the features are more durable than surface chemistry and can be modified in size and shape to suit the desired application. In this paper, nanotopography is examined as a means to guide differentiation, and its application is described in the context of different subsets of stem cells, with a particular focus on skeletal (mesenchymal stem cells. To address the mechanistic basis underlying the topographical effects on stem cells, the likely contributions of indirect (biochemical signal-mediated and direct (force-mediated mechanotransduction are discussed. Data from proteomic research is also outlined in relation to topography-mediated fate determination, as this approach provides insight into the global molecular changes at the level of the functional effectors.

  16. Biophysical regulation of stem cell differentiation.

    Science.gov (United States)

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

    2013-06-01

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

  17. The genetic network controlling plasma cell differentiation.

    Science.gov (United States)

    Nutt, Stephen L; Taubenheim, Nadine; Hasbold, Jhagvaral; Corcoran, Lynn M; Hodgkin, Philip D

    2011-10-01

    Upon activation by antigen, mature B cells undergo immunoglobulin class switch recombination and differentiate into antibody-secreting plasma cells, the endpoint of the B cell developmental lineage. Careful quantitation of these processes, which are stochastic, independent and strongly linked to the division history of the cell, has revealed that populations of B cells behave in a highly predictable manner. Considerable progress has also been made in the last few years in understanding the gene regulatory network that controls the B cell to plasma cell transition. The mutually exclusive transcriptomes of B cells and plasma cells are maintained by the antagonistic influences of two groups of transcription factors, those that maintain the B cell program, including Pax5, Bach2 and Bcl6, and those that promote and facilitate plasma cell differentiation, notably Irf4, Blimp1 and Xbp1. In this review, we discuss progress in the definition of both the transcriptional and cellular events occurring during late B cell differentiation, as integrating these two approaches is crucial to defining a regulatory network that faithfully reflects the stochastic features and complexity of the humoral immune response. 2011 Elsevier Ltd. All rights reserved.

  18. A 2D/3D image analysis system to track fluorescently labeled structures in rod-shaped cells: application to measure spindle pole asymmetry during mitosis.

    Science.gov (United States)

    Schmitter, Daniel; Wachowicz, Paulina; Sage, Daniel; Chasapi, Anastasia; Xenarios, Ioannis; Simanis; Unser, Michael

    2013-01-01

    The yeast Schizosaccharomyces pombe is frequently used as a model for studying the cell cycle. The cells are rod-shaped and divide by medial fission. The process of cell division, or cytokinesis, is controlled by a network of signaling proteins called the Septation Initiation Network (SIN); SIN proteins associate with the SPBs during nuclear division (mitosis). Some SIN proteins associate with both SPBs early in mitosis, and then display strongly asymmetric signal intensity at the SPBs in late mitosis, just before cytokinesis. This asymmetry is thought to be important for correct regulation of SIN signaling, and coordination of cytokinesis and mitosis. In order to study the dynamics of organelles or large protein complexes such as the spindle pole body (SPB), which have been labeled with a fluorescent protein tag in living cells, a number of the image analysis problems must be solved; the cell outline must be detected automatically, and the position and signal intensity associated with the structures of interest within the cell must be determined. We present a new 2D and 3D image analysis system that permits versatile and robust analysis of motile, fluorescently labeled structures in rod-shaped cells. We have designed an image analysis system that we have implemented as a user-friendly software package allowing the fast and robust image-analysis of large numbers of rod-shaped cells. We have developed new robust algorithms, which we combined with existing methodologies to facilitate fast and accurate analysis. Our software permits the detection and segmentation of rod-shaped cells in either static or dynamic (i.e. time lapse) multi-channel images. It enables tracking of two structures (for example SPBs) in two different image channels. For 2D or 3D static images, the locations of the structures are identified, and then intensity values are extracted together with several quantitative parameters, such as length, width, cell orientation, background fluorescence and

  19. Adaptive Spindle Balancing Using Magnetically Levitated Bearings

    International Nuclear Information System (INIS)

    BARNEY, PATRICK S.; LAUFFER, JAMES P.; PETTEYS, REBECCA; REDMOND, JAMES M.; SULLIVAN, WILLIAM N.

    1999-01-01

    A technological break through for supporting rotating shafts is the active magnetic bearing (AMB). Active magnetic bearings offer some important advantages over conventional ball, roller or journal bearings such as reduced frictional drag, no physical contact in the bearing, no need for lubricants, compatibility with high vacuum and ultra-clean environments, and ability to control shaft position within the bearing. The disadvantages of the AMB system are the increased cost and complexity, reduced bearing stiffness and the need for a controller. Still, there are certain applications, such as high speed machining, biomedical devices, and gyroscopes, where the additional cost of an AMB system can be justified. The inherent actuator capabilities of the AMB offer the potential for active balancing of spindles and micro-shaping capabilities for machine tools, The work presented in this paper concentrates on an AMB test program that utilizes the actuator capability to dynamically balance a spindle. In this study, an unbalanced AMB spindle system was enhanced with an LMS (Least Mean Squares) algorithm combined with an existing PID (proportional, integral, differential) control. This enhanced controller significantly improved the concentricity of an intentionally unbalanced shaft. The study included dynamic system analysis, test validation, control design and simulation, as well as experimental implementation using a digital LMS controller

  20. CENP-W plays a role in maintaining bipolar spindle structure.

    Directory of Open Access Journals (Sweden)

    Agnieszka Kaczmarczyk

    Full Text Available The CENP-W/T complex was previously reported to be required for mitosis. HeLa cells depleted of CENP-W displayed profound mitotic defects, with mitotic timing delay, disorganized prometaphases and multipolar spindles as major phenotypic consequences. In this study, we examined the process of multipolar spindle formation induced by CENP-W depletion. Depletion of CENP-W in HeLa cells labeled with histone H2B and tubulin fluorescent proteins induced rapid fragmentation of originally bipolar spindles in a high proportion of cells. CENP-W depletion was associated with depletion of Hec1 at kinetochores. The possibility of promiscuous centrosomal duplication was ruled out by immunofluorescent examination of centrioles. However, centrioles were frequently observed to be abnormally split. In addition, a large proportion of the supernumerary poles lacked centrioles, but were positively stained with different centrosomal markers. These observations suggested that perturbation in spindle force distribution caused by defective kinetochores could contribute to a mechanical mechanism for spindle pole disruption. 'Spindle free' nocodazole arrested cells did not exhibit pole fragmentation after CENP-W depletion, showing that pole fragmentation is microtubule dependent. Inhibition of centrosome separation by monastrol reduced the incidence of spindle pole fragmentation, indicating that Eg5 plays a role in spindle pole disruption. Surprisingly, CENP-W depletion rescued the monopolar spindle phenotype of monastrol treatment, with an increased frequency of bipolar spindles observed after CENP-W RNAi. We overexpressed the microtubule cross-linking protein TPX2 to create spindle poles stabilized by the microtubule cross-linking activity of TPX2. Spindle pole fragmentation was suppressed in a TPX2-dependent fashion. We propose that CENP-W, by influencing proper kinetochore assembly, particularly microtubule docking sites, can confer spindle pole resistance to traction

  1. CENP-W Plays a Role in Maintaining Bipolar Spindle Structure

    Science.gov (United States)

    Kaczmarczyk, Agnieszka; Sullivan, Kevin F.

    2014-01-01

    The CENP-W/T complex was previously reported to be required for mitosis. HeLa cells depleted of CENP-W displayed profound mitotic defects, with mitotic timing delay, disorganized prometaphases and multipolar spindles as major phenotypic consequences. In this study, we examined the process of multipolar spindle formation induced by CENP-W depletion. Depletion of CENP-W in HeLa cells labeled with histone H2B and tubulin fluorescent proteins induced rapid fragmentation of originally bipolar spindles in a high proportion of cells. CENP-W depletion was associated with depletion of Hec1 at kinetochores. The possibility of promiscuous centrosomal duplication was ruled out by immunofluorescent examination of centrioles. However, centrioles were frequently observed to be abnormally split. In addition, a large proportion of the supernumerary poles lacked centrioles, but were positively stained with different centrosomal markers. These observations suggested that perturbation in spindle force distribution caused by defective kinetochores could contribute to a mechanical mechanism for spindle pole disruption. ‘Spindle free’ nocodazole arrested cells did not exhibit pole fragmentation after CENP-W depletion, showing that pole fragmentation is microtubule dependent. Inhibition of centrosome separation by monastrol reduced the incidence of spindle pole fragmentation, indicating that Eg5 plays a role in spindle pole disruption. Surprisingly, CENP-W depletion rescued the monopolar spindle phenotype of monastrol treatment, with an increased frequency of bipolar spindles observed after CENP-W RNAi. We overexpressed the microtubule cross-linking protein TPX2 to create spindle poles stabilized by the microtubule cross-linking activity of TPX2. Spindle pole fragmentation was suppressed in a TPX2-dependent fashion. We propose that CENP-W, by influencing proper kinetochore assembly, particularly microtubule docking sites, can confer spindle pole resistance to traction forces exerted

  2. Thrombopoietin inhibits murine mast cell differentiation

    Science.gov (United States)

    Martelli, Fabrizio; Ghinassi, Barbara; Lorenzini, Rodolfo; Vannucchi, Alessandro M; Rana, Rosa Alba; Nishikawa, Mitsuo; Partamian, Sandra; Migliaccio, Giovanni; Migliaccio, Anna Rita

    2009-01-01

    We have recently shown that Mpl, the thrombopoietin receptor, is expressed on murine mast cells and on their precursors and that targeted deletion of the Mpl gene increases mast cell differentiation in mice. Here we report that treatment of mice with thrombopoietin, or addition of this growth factor to bone marrow-derived mast cell cultures, severely hampers the generation of mature cells from their precursors by inducing apoptosis. Analysis of the expression profiling of mast cells obtained in the presence of thrombopoietin suggests that thrombopoietin induces apoptosis of mast cells by reducing expression of the transcription factor Mitf and its target anti-apoptotic gene Bcl2. PMID:18276801

  3. Spindle neurons of the human anterior cingulate cortex

    Science.gov (United States)

    Nimchinsky, E. A.; Vogt, B. A.; Morrison, J. H.; Hof, P. R.; Bloom, F. E. (Principal Investigator)

    1995-01-01

    The human anterior cingulate cortex is distinguished by the presence of an unusual cell type, a large spindle neuron in layer Vb. This cell has been noted numerous times in the historical literature but has not been studied with modern neuroanatomic techniques. For instance, details regarding the neuronal class to which these cells belong and regarding their precise distribution along both ventrodorsal and anteroposterior axes of the cingulate gyrus are still lacking. In the present study, morphological features and the anatomic distribution of this cell type were studied using computer-assisted mapping and immunocytochemical techniques. Spindle neurons are restricted to the subfields of the anterior cingulate cortex (Brodmann's area 24), exhibiting a greater density in anterior portions of this area than in posterior portions, and tapering off in the transition zone between anterior and posterior cingulate cortex. Furthermore, a majority of the spindle cells at any level is located in subarea 24b on the gyral surface. Immunocytochemical analysis revealed that the neurofilament protein triple was present in a large percentage of these neurons and that they did not contain calcium-binding proteins. Injections of the carbocyanine dye DiI into the cingulum bundle revealed that these cells are projection neurons. Finally, spindle cells were consistently affected in Alzheimer's disease cases, with an overall loss of about 60%. Taken together, these observations indicate that the spindle cells of the human cingulate cortex represent a morphological subpopulation of pyramidal neurons whose restricted distribution may be associated with functionally distinct areas.

  4. A novel cell culture model for studying differentiation and apoptosis in the mouse mammary gland

    International Nuclear Information System (INIS)

    Gordon, Katrina E; Binas, Bert; Chapman, Rachel S; Kurian, Kathreena M; Clarkson, Richard W E; John Clark, A; Birgitte Lane, E; Watson, Christine J

    2000-01-01

    This paper describes the derivation and characterization of a novel, conditionally immortal mammary epithelial cell line named KIM-2. These cells were derived from mid-pregnant mammary glands of a mouse harbouring one to two copies of a transgene comprised of the ovine β-lactoglobulin milk protein gene promoter, driving expression of a temperature-sensitive variant of simian virus-40 (SV40) large T antigen (T-Ag). KIM-2 cells have a characteristic luminal epithelial cell morphology and a stable, nontransformed phenotype at the semipermissive temperature of 37°C. In contrast, at the permissive temperature of 33°C the cells have an elongated spindle-like morphology and become transformed after prolonged culture. Differentiation of KIM-2 cells at 37°C, in response to lactogenic hormones, results in the formation of polarized dome-like structures with tight junctions. This is accompanied by expression of the milk protein genes that encode β-casein and whey acidic protein (WAP), and activation of the prolactin signalling molecule, signal transducer and activator of transcription (STAT)5. Fully differentiated KIM-2 cultures at 37°C become dependent on lactogenic hormones for survival and undergo extensive apoptosis upon hormone withdrawal, as indicated by nuclear morphology and flow cytometric analysis. KIM-2 cells can be genetically modified by stable transfection and clonal lines isolated that retain the characteristics of untransfected cells. KIM-2 cells are a valuable addition, therefore, to currently available lines of mammary epithelial cells. Their capacity for extensive differentiation in the absence of exogenously added basement membrane, and ability to undergo apoptosis in response to physiological signals will provide an invaluable model system for the study of signal transduction pathways and transcriptional regulatory mechanisms that control differentiation and involution in the mammary gland

  5. The Antigen Presenting Cells Instruct Plasma Cell Differentiation

    Directory of Open Access Journals (Sweden)

    Wei eXu

    2014-01-01

    Full Text Available The professional antigen presenting cells (APCs, including many subsets of dendritic cells and macrophages, not only mediate prompt but nonspecific response against microbes, but also bridge the antigen-specific adaptive immune response through antigen presentation. In the latter, typically activated B cells acquire cognate signals from T helper cells in the germinal center of lymphoid follicles to differentiate into plasma cells, which generate protective antibodies. Recent advances have revealed that many APC subsets provide not only signal 1 (the antigen, but also signal 2 to directly instruct the differentiation process of plasma cells in a T cell-independent manner. Herein, the different signals provided by these APC subsets to direct B cell proliferation, survival, class switching and terminal differentiation are discussed. We furthermore propose that the next generation of vaccines for boosting antibody response could be designed by targeting APCs.

  6. Tracking plasma cell differentiation and survival.

    Science.gov (United States)

    Roth, Katrin; Oehme, Laura; Zehentmeier, Sandra; Zhang, Yang; Niesner, Raluca; Hauser, Anja E

    2014-01-01

    Plasma cells play a crucial role for the humoral immune response as they represent the body's factories for antibody production. The differentiation from a B cell into a plasma cell is controlled by a complex transcriptional network and happens within secondary lymphoid organs. Based on their lifetime, two types of antibody secreting cells can be distinguished: Short-lived plasma cells are located in extrafollicular sites of secondary lymphoid organs such as lymph node medullary cords and the splenic red pulp. A fraction of plasmablasts migrate from secondary lymphoid organs to the bone marrow where they can become long-lived plasma cells. Bone marrow plasma cells reside in special microanatomical environments termed survival niches, which provide factors promoting their longevity. Reticular stromal cells producing the chemokine CXCL12, which is known to attract plasmablasts to the bone marrow but also to promote plasma cell survival, play a crucial role in the maintenance of these niches. In addition, hematopoietic cells are contributing to the niches by providing other soluble survival factors. Here, we review the current knowledge on the factors involved in plasma cell differentiation, their localization and migration. We also give an overview on what is known regarding the maintenance of long lived plasma cells in survival niches of the bone marrow. © 2013 International Society for Advancement of Cytometry.

  7. The spindle assembly checkpoint: More than just keeping track of the spindle.

    OpenAIRE

    Lawrence, KS; Engebrecht, J

    2015-01-01

    Genome stability is essential for cell proliferation and survival. Consequently, genome integrity is monitored by two major checkpoints, the DNA damage response (DDR) and the spindle assembly checkpoint (SAC). The DDR monitors DNA lesions in G1, S, and G2 stages of the cell cycle and the SAC ensures proper chromosome segregation in M phase. There have been extensive studies characterizing the roles of these checkpoints in response to the processes for which they are named; however, emerging e...

  8. Bioprinting and Differentiation of Stem Cells

    Directory of Open Access Journals (Sweden)

    Scott A. Irvine

    2016-09-01

    Full Text Available The 3D bioprinting of stem cells directly into scaffolds offers great potential for the development of regenerative therapies; in particular for the fabrication of organ and tissue substitutes. For this to be achieved; the lineage fate of bioprinted stem cell must be controllable. Bioprinting can be neutral; allowing culture conditions to trigger differentiation or alternatively; the technique can be designed to be stimulatory. Such factors as the particular bioprinting technique; bioink polymers; polymer cross-linking mechanism; bioink additives; and mechanical properties are considered. In addition; it is discussed that the stimulation of stem cell differentiation by bioprinting may lead to the remodeling and modification of the scaffold over time matching the concept of 4D bioprinting. The ability to tune bioprinting properties as an approach to fabricate stem cell bearing scaffolds and to also harness the benefits of the cells multipotency is of considerable relevance to the field of biomaterials and bioengineering.

  9. The influence of scaffold microstructure on chondrogenic differentiation of mesenchymal stem cells

    International Nuclear Information System (INIS)

    Zhang, Jingjing; Ge, Zigang; Wu, Yingnan; Lee, Eng Hin; Thote, Tanushree; Yang, Zheng

    2014-01-01

    Different forms of biomaterials, including microspheres, sponges, hydrogels and nanofibres have been broadly used in cartilage regeneration; however, effects of internal structures of biomaterials on chondrogenesis of mesenchymal stem cells (MSCs) remain largely unexplored. Here we investigated the effect of physical microenvironments of sponges and hydrogels on chondrogenic differentiation of MSCs. MSCs, cultured in these two scaffold systems, were induced with TGF-β 3  in chondrogeneic differentiation medium and the chondrogenic differentiation was evaluated and compared after three weeks. MSCs in the sponges clustered with spindle morphologies, while they distributed homogenously with round morphologies in the hydrogel. The MSCs proliferated faster in the sponge compared to that in the hydrogel. Significantly higher glycosaminoglycan and collagen II were found in the sponges but not in the hydrogels. The different tissue formation ability of MSCs in these two systems could be attributed to the different metabolic requirements and the cellular events prerequisite in the chondrogenic process of MSCs. It is reasonable to conclude that sponges with relatively active microenvironments that facilitate cell–cell contacts and cell–matrix interaction are optimal for early stage of chondrogeneic differentiation. (paper)

  10. The antigen presenting cells instruct plasma cell differentiation.

    Science.gov (United States)

    Xu, Wei; Banchereau, Jacques

    2014-01-06

    The professional antigen presenting cells (APCs), including many subsets of dendritic cells and macrophages, not only mediate prompt but non-specific response against microbes, but also bridge the antigen-specific adaptive immune response through antigen presentation. In the latter, typically activated B cells acquire cognate signals from T helper cells in the germinal center of lymphoid follicles to differentiate into plasma cells (PCs), which generate protective antibodies. Recent advances have revealed that many APC subsets provide not only "signal 1" (the antigen), but also "signal 2" to directly instruct the differentiation process of PCs in a T-cell-independent manner. Herein, the different signals provided by these APC subsets to direct B cell proliferation, survival, class switching, and terminal differentiation are discussed. We furthermore propose that the next generation of vaccines for boosting antibody response could be designed by targeting APCs.

  11. The structure of the mitotic spindle and nucleolus during mitosis in the amebo-flagellate Naegleria.

    Science.gov (United States)

    Walsh, Charles J

    2012-01-01

    Mitosis in the amebo-flagellate Naegleria pringsheimi is acentrosomal and closed (the nuclear membrane does not break down). The large central nucleolus, which occupies about 20% of the nuclear volume, persists throughout the cell cycle. At mitosis, the nucleolus divides and moves to the poles in association with the chromosomes. The structure of the mitotic spindle and its relationship to the nucleolus are unknown. To identify the origin and structure of the mitotic spindle, its relationship to the nucleolus and to further understand the influence of persistent nucleoli on cellular division in acentriolar organisms like Naegleria, three-dimensional reconstructions of the mitotic spindle and nucleolus were carried out using confocal microscopy. Monoclonal antibodies against three different nucleolar regions and α-tubulin were used to image the nucleolus and mitotic spindle. Microtubules were restricted to the nucleolus beginning with the earliest prophase spindle microtubules. Early spindle microtubules were seen as short rods on the surface of the nucleolus. Elongation of the spindle microtubules resulted in a rough cage of microtubules surrounding the nucleolus. At metaphase, the mitotic spindle formed a broad band completely embedded within the nucleolus. The nucleolus separated into two discreet masses connected by a dense band of microtubules as the spindle elongated. At telophase, the distal ends of the mitotic spindle were still completely embedded within the daughter nucleoli. Pixel by pixel comparison of tubulin and nucleolar protein fluorescence showed 70% or more of tubulin co-localized with nucleolar proteins by early prophase. These observations suggest a model in which specific nucleolar binding sites for microtubules allow mitotic spindle formation and attachment. The fact that a significant mass of nucleolar material precedes the chromosomes as the mitotic spindle elongates suggests that spindle elongation drives nucleolar division.

  12. Schwann cells promote neuronal differentiation of bone marrow ...

    African Journals Online (AJOL)

    Administrator

    2011-04-25

    Apr 25, 2011 ... Bone marrow stromal cells (BMSCs), a type of multipotent stem cell, can differentiate into various types ... induced to differentiate into neuron-like cells when they are ... axonal regeneration and functional reconstruction do not.

  13. Human mesenchymal stem cells derived from limb bud can differentiate into all three embryonic germ layers lineages.

    Science.gov (United States)

    Jiao, Fei; Wang, Juan; Dong, Zhao-Lun; Wu, Min-Juan; Zhao, Ting-Bao; Li, Dan-Dan; Wang, Xin

    2012-08-01

    Mesenchymal stem cells (MSCs) have been isolated from many sources, including adults and fetuses. Previous studies have demonstrated that, compared with their adult counterpart, fetal MSCs with several remarkable advantages may be a better resource for clinical applications. In this study, we successfully isolated a rapidly proliferating cell population from limb bud of aborted fetus and termed them "human limb bud-derived mesenchymal stem cells" (hLB-MSCs). Characteristics of their morphology, phenotype, cell cycle, and differentiation properties were analyzed. These adherent cell populations have a typically spindle-shaped morphology. Flow cytometry analysis showed that hLB-MSCs are positive for CD13, CD29, CD90, CD105, and CD106, but negative for CD3, CD4, CD5, CD11b, CD14, CD15, CD34, CD45, CD45RA, and HLA-DR. The detection of cell cycle from different passages indicated that hLB-MSCs have a similar potential for propagation during long culture in vitro. The most novel finding here is that, in addition to their mesodermal differentiation (osteoblasts and adipocytes), hLB-MSCs can also differentiated into extramesenchymal lineages, such as neural (ectoderm) and hepatic (endoderm) progenies. These results indicate that hLB-MSCs have a high level of plasticity and can differentiate into cell lineages from all three embryonic layers in vitro.

  14. Differential white cell count by centrifugal microfluidics.

    Energy Technology Data Exchange (ETDEWEB)

    Sommer, Gregory Jon; Tentori, Augusto M.; Schaff, Ulrich Y.

    2010-07-01

    We present a method for counting white blood cells that is uniquely compatible with centrifugation based microfluidics. Blood is deposited on top of one or more layers of density media within a microfluidic disk. Spinning the disk causes the cell populations within whole blood to settle through the media, reaching an equilibrium based on the density of each cell type. Separation and fluorescence measurement of cell types stained with a DNA dye is demonstrated using this technique. The integrated signal from bands of fluorescent microspheres is shown to be proportional to their initial concentration in suspension. Among the current generation of medical diagnostics are devices based on the principle of centrifuging a CD sized disk functionalized with microfluidics. These portable 'lab on a disk' devices are capable of conducting multiple assays directly from a blood sample, embodied by platforms developed by Gyros, Samsung, and Abaxis. [1,2] However, no centrifugal platform to date includes a differential white blood cell count, which is an important metric complimentary to diagnostic assays. Measuring the differential white blood cell count (the relative fraction of granulocytes, lymphocytes, and monocytes) is a standard medical diagnostic technique useful for identifying sepsis, leukemia, AIDS, radiation exposure, and a host of other conditions that affect the immune system. Several methods exist for measuring the relative white blood cell count including flow cytometry, electrical impedance, and visual identification from a stained drop of blood under a microscope. However, none of these methods is easily incorporated into a centrifugal microfluidic diagnostic platform.

  15. Manipulating the cell differentiation through lentiviral vectors.

    Science.gov (United States)

    Coppola, Valeria; Galli, Cesare; Musumeci, Maria; Bonci, Désirée

    2010-01-01

    The manipulation of cell differentiation is important to create new sources for the treatment of degenerative diseases or solve cell depletion after aggressive therapy against cancer. In this chapter, the use of a tissue-specific promoter lentiviral vector to obtain a myocardial pure lineage from murine embryonic stem cells (mES) is described in detail. Since the cardiac isoform of troponin I gene product is not expressed in skeletal or other muscle types, short mouse cardiac troponin proximal promoter is used to drive reporter genes. Cells are infected simultaneously with two lentiviral vectors, the first expressing EGFP to monitor the transduction efficiency, and the other expressing a puromycin resistance gene to select the specific cells of interest. This technical approach describes a method to obtain a pure cardiomyocyte population and can be applied to other lineages of interest.

  16. Cell differentiation: therapeutical challenges in diabetes.

    Science.gov (United States)

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

    2012-01-01

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

  17. [EXPERIMENTAL RESEARCH OF DIFFERENTIATION OF HUMAN AMNIOTIC MESENCHYMAL STEM CELLS INTO LIGAMENT CELLS IN VITRO].

    Science.gov (United States)

    Jin, Ying; Li, Yuwan; Zhang, Chenghao; Wu, Shuhong; Cheng, Daixiong; Liu, Yi

    2016-02-01

    To discuss whether human amniotic mesenchymal stem cells (hAMSCs) possesses the characteristic of mesenchymal stem cells, and could differentiate into ligament cells in vitro after induction. The hAMSCs were separated through enzyme digestion, and the phenotypic characteristics of hAMSCs were tested through flow cytometry. The cells at passage 3 were cultured with L-DMEM/F12 medium containing transforming growth factor beta1 (TGF-beta1) + basic fibroblast growth factor (bFGF) (group A), containing hyaluronic acid (HA) (group B), containing TGF-beta1+bFGF+HA (group C), and simple L-DMEM/F12 medium (group D) as control group. The morphology changes of cells in each group were observed by inverted phase contrast microscope at 21 days after induction; the cellular activities and proliferation were examined by sulforhodamine (SRB) colorimetric method; and specific mRNA and protein expressions of ligament including collagen type I, collagen type III, and tenascin C (TNC) were measured by real-time fluorescence quantitative PCR and immunohistochemical staining. The flow cytometry result indicated that hAMSCs expressed mesenchymal stem cell phenotype. After 21 days of induction, the cells in groups A, B, and C grew like spindle-shaped fibroblasts under inverted phase contrast microscope, and cells showed single shape, obvious directivity, and compact arrangement in group C. The SRB result indicated that the cells in each group reached the peak of growth curve at 6 days; the cellular activities of groups A, B, and C were significantly higher than that of group D at 6 days after induction. Also, the immunohistochemical staining results showed that no expressions of TNC were detected in 4 groups at 7 days; expressions of collagen type I in groups A, B, and C were significantly higher than that in group D at 7, 14, and 21 days (Pligament specific genes can be up-regulated and the synthesis of ligament specific proteins can be also strengthened. As a result, it can be used as

  18. Andrographolide Promotes Neural Differentiation of Rat Adipose Tissue-Derived Stromal Cells through Wnt/β-Catenin Signaling Pathway

    Directory of Open Access Journals (Sweden)

    Yan Liang

    2017-01-01

    Full Text Available Adipose tissue-derived stromal cells (ADSCs are a high-yield source of pluripotent stem cells for use in cell-based therapies. We explored the effect of andrographolide (ANDRO, one of the ingredients of the medicinal herb extract on the neural differentiation of rat ADSCs and associated molecular mechanisms. We observed that rat ADSCs were small and spindle-shaped and expressed multiple stem cell markers including nestin. They were multipotent as evidenced by adipogenic, osteogenic, chondrogenic, and neural differentiation under appropriate conditions. The proportion of cells exhibiting neural-like morphology was higher, and neurites developed faster in the ANDRO group than in the control group in the same neural differentiation medium. Expression levels of the neural lineage markers MAP2, tau, GFAP, and β-tubulin III were higher in the ANDRO group. ANDRO induced a concentration-dependent increase in Wnt/β-catenin signaling as evidenced by the enhanced expression of nuclear β-catenin and the inhibited form of GSK-3β (pSer9. Thus, this study shows for the first time how by enhancing the neural differentiation of ADSCs we expect that ANDRO pretreatment may increase the efficacy of adult stem cell transplantation in nervous system diseases, but more exploration is needed.

  19. A Comparative Study to Evaluate Myogenic Differentiation Potential of Human Chorion versus Umbilical Cord Blood-derived Mesenchymal Stem Cells.

    Science.gov (United States)

    Bana, Nikoo; Sanooghi, Davood; Soleimani, Mansoureh; Hayati Roodbari, Nasim; Alavi Moghaddam, Sepideh; Joghataei, Mohammad Taghi; Sayahpour, Forough Azam; Faghihi, Faezeh

    2017-08-01

    Musculodegenerative diseases threaten the life of many patients in the world. Since drug administration is not efficient in regeneration of damaged tissues, stem cell therapy is considered as a good strategy to restore the lost cells. Since the efficiency of myogenic differentiation potential of human Chorion- derived Mesenchymal Stem Cells (C-MSCs) has not been addressed so far; we set out to evaluate myogenic differentiation property of these cells in comparison with Umbilical Cord Blood- derived Mesenchymal Stem Cells (UCB-MSCs) in the presence of 5-azacytidine. To do that, neonate placenta Umbilical Cord Blood were transferred to the lab. After characterization of the isolated cells using flowcytometry and multilineage differentiation capacity, the obtained Mesenchymal Stem Cells were cultured in DMEM/F12 supplemented with 2% FBS and 10μM of 5-azacytidine to induce myogenic differentiation. Real-time PCR and immunocytochemistry were used to assess the myogenic properties of the cells. Our data showed that C-MSCs and UCB-MSCs were spindle shape in morphology. They were positive for CD90, CD73 and CD44 antigens, and negative for hematopoietic markers. They also differentiated into osteoblast and adipoblast lineages. Real-time PCR results showed that the cells could express MyoD, desmin and α-MHC at the end of the first week (P<0.05). No significant upregulation was detected in the expression of GATA-4 in both groups. Immunocytochemical staining revealed the expression of Desmin, cTnT and α-MHC. Results showed that these cells are potent to differentiate into myoblast- like cells. An upregulation in the expression of some myogenic markers (desmin, α- MHC) was observed in C-MSCs in comparison with UCB-MSCs. Copyright © 2017. Published by Elsevier Ltd.

  20. In vitro differentiation of mouse embryonic stem cells into functional ...

    African Journals Online (AJOL)

    Studies have shown that embryonic stem (ES) cells can be successfully differentiated into liver cells, which offer the potential unlimited cell source for a variety of end-stage liver disease. In our study, in order to induce mouse ES cells to differentiate into hepatocyte-like cells under chemically defined conditions, ES cells ...

  1. In-silico modeling of the mitotic spindle assembly checkpoint.

    Directory of Open Access Journals (Sweden)

    Bashar Ibrahim

    2008-02-01

    Full Text Available The Mitotic Spindle Assembly Checkpoint ((MSAC is an evolutionary conserved mechanism that ensures the correct segregation of chromosomes by restraining cell cycle progression from entering anaphase until all chromosomes have made proper bipolar attachments to the mitotic spindle. Its malfunction can lead to cancer.We have constructed and validated for the human (MSAC mechanism an in silico dynamical model, integrating 11 proteins and complexes. The model incorporates the perspectives of three central control pathways, namely Mad1/Mad2 induced Cdc20 sequestering based on the Template Model, MCC formation, and APC inhibition. Originating from the biochemical reactions for the underlying molecular processes, non-linear ordinary differential equations for the concentrations of 11 proteins and complexes of the (MSAC are derived. Most of the kinetic constants are taken from literature, the remaining four unknown parameters are derived by an evolutionary optimization procedure for an objective function describing the dynamics of the APC:Cdc20 complex. MCC:APC dissociation is described by two alternatives, namely the "Dissociation" and the "Convey" model variants. The attachment of the kinetochore to microtubuli is simulated by a switching parameter silencing those reactions which are stopped by the attachment. For both, the Dissociation and the Convey variants, we compare two different scenarios concerning the microtubule attachment dependent control of the dissociation reaction. Our model is validated by simulation of ten perturbation experiments.Only in the controlled case, our models show (MSAC behaviour at meta- to anaphase transition in agreement with experimental observations. Our simulations revealed that for (MSAC activation, Cdc20 is not fully sequestered; instead APC is inhibited by MCC binding.

  2. The epigenomics of embryonic stem cell differentiation.

    Science.gov (United States)

    Kraushaar, Daniel C; Zhao, Keji

    2013-01-01

    Embryonic stem cells (ESCs) possess an open and highly dynamic chromatin landscape, which underlies their plasticity and ultimately maintains ESC pluripotency. The ESC epigenome must not only maintain the transcription of pluripotency-associated genes but must also, through gene priming, facilitate rapid and cell type-specific activation of developmental genes upon lineage commitment. Trans-generational inheritance ensures that the ESC chromatin state is stably transmitted from one generation to the next; yet at the same time, epigenetic marks are highly dynamic, reversible and responsive to extracellular cues. Once committed to differentiation, the ESC epigenome is remodeled and resolves into a more compact chromatin state. A thorough understanding of the role of chromatin modifiers in ESC fate and differentiation will be important if they are to be used for therapeutic purposes. Recent technical advances, particularly in next-generation sequencing technologies, have provided a genome-scale view of epigenetic marks and chromatin modifiers. More affordable and faster sequencing platforms have led to a comprehensive characterization of the ESC epigenome and epigenomes of differentiated cell types. In this review, we summarize and discuss the recent progress that has highlighted the central role of histone modifications, histone variants, DNA methylation and chromatin modifiers in ESC pluripotency and ESC fate. We provide a detailed and comprehensive discussion of genome-wide studies that are pertinent to our understanding of mammalian development.

  3. Constitutive Cdk2 activity promotes aneuploidy while altering the spindle assembly and tetraploidy checkpoints

    DEFF Research Database (Denmark)

    Jahn, Stephan C; Corsino, Patrick E; Davis, Bradley J

    2013-01-01

    instability. Expression of these complexes in the MCF10A cell line leads to retinoblastoma protein (Rb) hyperphosphorylation, a subsequent increase in proliferation rate, and increased expression of the spindle assembly checkpoint protein Mad2. This results in a strengthening of the spindle assembly...

  4. Proteomic cornerstones of hematopoietic stem cell differentiation

    DEFF Research Database (Denmark)

    Klimmeck, Daniel; Hansson, Jenny; Raffel, Simon

    2012-01-01

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

  5. Noninvasive three-dimensional live imaging methodology for the spindles at meiosis and mitosis

    Science.gov (United States)

    Zheng, Jing-gao; Huo, Tiancheng; Tian, Ning; Chen, Tianyuan; Wang, Chengming; Zhang, Ning; Zhao, Fengying; Lu, Danyu; Chen, Dieyan; Ma, Wanyun; Sun, Jia-lin; Xue, Ping

    2013-05-01

    The spindle plays a crucial role in normal chromosome alignment and segregation during meiosis and mitosis. Studying spindles in living cells noninvasively is of great value in assisted reproduction technology (ART). Here, we present a novel spindle imaging methodology, full-field optical coherence tomography (FF-OCT). Without any dye labeling and fixation, we demonstrate the first successful application of FF-OCT to noninvasive three-dimensional (3-D) live imaging of the meiotic spindles within the mouse living oocytes at metaphase II as well as the mitotic spindles in the living zygotes at metaphase and telophase. By post-processing of the 3-D dataset obtained with FF-OCT, the important morphological and spatial parameters of the spindles, such as short and long axes, spatial localization, and the angle of meiotic spindle deviation from the first polar body in the oocyte were precisely measured with the spatial resolution of 0.7 μm. Our results reveal the potential of FF-OCT as an imaging tool capable of noninvasive 3-D live morphological analysis for spindles, which might be useful to ART related procedures and many other spindle related studies.

  6. Nap sleep spindle correlates of intelligence.

    Science.gov (United States)

    Ujma, Péter P; Bódizs, Róbert; Gombos, Ferenc; Stintzing, Johannes; Konrad, Boris N; Genzel, Lisa; Steiger, Axel; Dresler, Martin

    2015-11-26

    Sleep spindles are thalamocortical oscillations in non-rapid eye movement (NREM) sleep, that play an important role in sleep-related neuroplasticity and offline information processing. Several studies with full-night sleep recordings have reported a positive association between sleep spindles and fluid intelligence scores, however more recently it has been shown that only few sleep spindle measures correlate with intelligence in females, and none in males. Sleep spindle regulation underlies a circadian rhythm, however the association between spindles and intelligence has not been investigated in daytime nap sleep so far. In a sample of 86 healthy male human subjects, we investigated the correlation between fluid intelligence and sleep spindle parameters in an afternoon nap of 100 minutes. Mean sleep spindle length, amplitude and density were computed for each subject and for each derivation for both slow and fast spindles. A positive association was found between intelligence and slow spindle duration, but not any other sleep spindle parameter. As a positive correlation between intelligence and slow sleep spindle duration in full-night polysomnography has only been reported in females but not males, our results suggest that the association between intelligence and sleep spindles is more complex than previously assumed.

  7. Skeletal myogenic differentiation of human urine-derived cells as a potential source for skeletal muscle regeneration.

    Science.gov (United States)

    Chen, Wei; Xie, Minkai; Yang, Bin; Bharadwaj, Shantaram; Song, Lujie; Liu, Guihua; Yi, Shanhong; Ye, Gang; Atala, Anthony; Zhang, Yuanyuan

    2017-02-01

    Stem cells are regarded as possible cell therapy candidates for skeletal muscle regeneration. However, invasive harvesting of those cells can cause potential harvest-site morbidity. The goal of this study was to assess whether human urine-derived stem cells (USCs), obtained through non-invasive procedures, can differentiate into skeletal muscle linage cells (Sk-MCs) and potentially be used for skeletal muscle regeneration. In this study, USCs were harvested from six healthy individuals aged 25-55. Expression profiles of cell-surface markers were assessed by flow cytometry. To optimize the myogenic differentiation medium, we selected two from four different types of myogenic differentiation media to induce the USCs. Differentiated USCs were identified with myogenic markers by gene and protein expression. USCs were implanted into the tibialis anterior muscles of nude mice for 1 month. The results showed that USCs displayed surface markers with positive staining for CD24, CD29, CD44, CD73, CD90, CD105, CD117, CD133, CD146, SSEA-4 and STRO-1, and negative staining for CD14, CD31, CD34 and CD45. After myogenic differentiation, a change in morphology was observed from 'rice-grain'-like cells to spindle-shaped cells. The USCs expressed specific Sk-MC transcripts and protein markers (myf5, myoD, myosin, and desmin) after being induced with different myogenic culture media. Implanted cells expressed Sk-MC markers stably in vivo. Our findings suggest that USCs are able to differentiate into the Sk-MC lineage in vitro and after being implanted in vivo. Thus, they might be a potential source for cell injection therapy in the use of skeletal muscle regeneration. Copyright © 2014 John Wiley & Sons, Ltd. Copyright © 2014 John Wiley & Sons, Ltd.

  8. Efficient myogenic differentiation of human adipose-derived stem cells by the transduction of engineered MyoD protein

    Energy Technology Data Exchange (ETDEWEB)

    Sung, Min Sun [Korea Research Institute of Bioscience and Biotechnology (KRIBB), 125 Gwahak-ro, Yuseong-gu, Daejeon 305-806 (Korea, Republic of); Biosystems and Bioengineering Program, University of Science and Technology (UST), Daejeon 305-350 (Korea, Republic of); Mun, Ji-Young [Korea Research Institute of Bioscience and Biotechnology (KRIBB), 125 Gwahak-ro, Yuseong-gu, Daejeon 305-806 (Korea, Republic of); Kwon, Ohsuk [Korea Research Institute of Bioscience and Biotechnology (KRIBB), 125 Gwahak-ro, Yuseong-gu, Daejeon 305-806 (Korea, Republic of); Biosystems and Bioengineering Program, University of Science and Technology (UST), Daejeon 305-350 (Korea, Republic of); Kwon, Ki-Sun [Korea Research Institute of Bioscience and Biotechnology (KRIBB), 125 Gwahak-ro, Yuseong-gu, Daejeon 305-806 (Korea, Republic of); Oh, Doo-Byoung, E-mail: dboh@kribb.re.kr [Korea Research Institute of Bioscience and Biotechnology (KRIBB), 125 Gwahak-ro, Yuseong-gu, Daejeon 305-806 (Korea, Republic of); Biosystems and Bioengineering Program, University of Science and Technology (UST), Daejeon 305-350 (Korea, Republic of)

    2013-07-19

    Highlights: •MyoD was engineered to contain protein transduction domain and endosome-disruptive INF7 peptide. •The engineered MyoD-IT showed efficient nuclear targeting through an endosomal escape by INF7 peptide. •By applying MyoD-IT, human adipose-derived stem cells (hASCs) were differentiated into myogenic cells. •hASCs differentiated by applying MyoD-IT fused to myotubes through co-culturing with mouse myoblasts. •Myogenic differentiation using MyoD-IT is a safe method without the concern of altering the genome. -- Abstract: Human adipose-derived stem cells (hASCs) have great potential as cell sources for the treatment of muscle disorders. To provide a safe method for the myogenic differentiation of hASCs, we engineered the MyoD protein, a key transcription factor for myogenesis. The engineered MyoD (MyoD-IT) was designed to contain the TAT protein transduction domain for cell penetration and the membrane-disrupting INF7 peptide, which is an improved version of the HA2 peptide derived from influenza. MyoD-IT showed greatly improved nuclear targeting ability through an efficient endosomal escape induced by the pH-sensitive membrane disruption of the INF7 peptide. By applying MyoD-IT to a culture, hASCs were efficiently differentiated into long spindle-shaped myogenic cells expressing myosin heavy chains. Moreover, these cells differentiated by an application of MyoD-IT fused to myotubes with high efficiency through co-culturing with mouse C2C12 myoblasts. Because internalized proteins can be degraded in cells without altering the genome, the myogenic differentiation of hASCs using MyoD-IT would be a safe and clinically applicable method.

  9. Efficient myogenic differentiation of human adipose-derived stem cells by the transduction of engineered MyoD protein

    International Nuclear Information System (INIS)

    Sung, Min Sun; Mun, Ji-Young; Kwon, Ohsuk; Kwon, Ki-Sun; Oh, Doo-Byoung

    2013-01-01

    Highlights: •MyoD was engineered to contain protein transduction domain and endosome-disruptive INF7 peptide. •The engineered MyoD-IT showed efficient nuclear targeting through an endosomal escape by INF7 peptide. •By applying MyoD-IT, human adipose-derived stem cells (hASCs) were differentiated into myogenic cells. •hASCs differentiated by applying MyoD-IT fused to myotubes through co-culturing with mouse myoblasts. •Myogenic differentiation using MyoD-IT is a safe method without the concern of altering the genome. -- Abstract: Human adipose-derived stem cells (hASCs) have great potential as cell sources for the treatment of muscle disorders. To provide a safe method for the myogenic differentiation of hASCs, we engineered the MyoD protein, a key transcription factor for myogenesis. The engineered MyoD (MyoD-IT) was designed to contain the TAT protein transduction domain for cell penetration and the membrane-disrupting INF7 peptide, which is an improved version of the HA2 peptide derived from influenza. MyoD-IT showed greatly improved nuclear targeting ability through an efficient endosomal escape induced by the pH-sensitive membrane disruption of the INF7 peptide. By applying MyoD-IT to a culture, hASCs were efficiently differentiated into long spindle-shaped myogenic cells expressing myosin heavy chains. Moreover, these cells differentiated by an application of MyoD-IT fused to myotubes with high efficiency through co-culturing with mouse C2C12 myoblasts. Because internalized proteins can be degraded in cells without altering the genome, the myogenic differentiation of hASCs using MyoD-IT would be a safe and clinically applicable method

  10. Directional differentiation of chicken embryonic stem cells into ...

    African Journals Online (AJOL)

    Jane

    2011-08-01

    Aug 1, 2011 ... In this study, the differentiation potential of chicken ES cells was investigated ... Key words: Chicken embryonic stem cells, in vitro, directional differentiation, .... synthesized by using the Revert Aid first strand cDNA synthesis kit.

  11. Regulatory T Cells in Skin Facilitate Epithelial Stem Cell Differentiation.

    Science.gov (United States)

    Ali, Niwa; Zirak, Bahar; Rodriguez, Robert Sanchez; Pauli, Mariela L; Truong, Hong-An; Lai, Kevin; Ahn, Richard; Corbin, Kaitlin; Lowe, Margaret M; Scharschmidt, Tiffany C; Taravati, Keyon; Tan, Madeleine R; Ricardo-Gonzalez, Roberto R; Nosbaum, Audrey; Bertolini, Marta; Liao, Wilson; Nestle, Frank O; Paus, Ralf; Cotsarelis, George; Abbas, Abul K; Rosenblum, Michael D

    2017-06-01

    The maintenance of tissue homeostasis is critically dependent on the function of tissue-resident immune cells and the differentiation capacity of tissue-resident stem cells (SCs). How immune cells influence the function of SCs is largely unknown. Regulatory T cells (Tregs) in skin preferentially localize to hair follicles (HFs), which house a major subset of skin SCs (HFSCs). Here, we mechanistically dissect the role of Tregs in HF and HFSC biology. Lineage-specific cell depletion revealed that Tregs promote HF regeneration by augmenting HFSC proliferation and differentiation. Transcriptional and phenotypic profiling of T regs and HFSCs revealed that skin-resident Tregs preferentially express high levels of the Notch ligand family member, Jagged 1 (Jag1). Expression of Jag1 on Tregs facilitated HFSC function and efficient HF regeneration. Taken together, our work demonstrates that Tregs in skin play a major role in HF biology by promoting the function of HFSCs. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. Dido3 PHD Modulates Cell Differentiation and Division

    Directory of Open Access Journals (Sweden)

    Jovylyn Gatchalian

    2013-07-01

    Full Text Available Death Inducer Obliterator 3 (Dido3 is implicated in the maintenance of stem cell genomic stability and tumorigenesis. Here, we show that Dido3 regulates the expression of stemness genes in embryonic stem cells through its plant homeodomain (PHD finger. Binding of Dido3 PHD to histone H3K4me3 is disrupted by threonine phosphorylation that triggers Dido3 translocation from chromatin to the mitotic spindle. The crystal structure of Dido3 PHD in complex with H3K4me3 reveals an atypical aromatic-cage-like binding site that contains a histidine residue. Biochemical, structural, and mutational analyses of the binding mechanism identified the determinants of specificity and affinity and explained the inability of homologous PHF3 to bind H3K4me3. Together, our findings reveal a link between the transcriptional control in embryonic development and regulation of cell division.

  13. Measuring and modeling polymer concentration profiles near spindle boundaries argues that spindle microtubules regulate their own nucleation

    Science.gov (United States)

    Kaye, Bryan; Stiehl, Olivia; Foster, Peter J.; Shelley, Michael J.; Needleman, Daniel J.; Fürthauer, Sebastian

    2018-05-01

    Spindles are self-organized microtubule-based structures that segregate chromosomes during cell division. The mass of the spindle is controlled by the balance between microtubule turnover and nucleation. The mechanisms that control the spatial regulation of microtubule nucleation remain poorly understood. While previous work found that microtubule nucleators bind to pre-existing microtubules in the spindle, it is still unclear whether this binding regulates the activity of those nucleators. Here we use a combination of experiments and mathematical modeling to investigate this issue. We measured the concentration of microtubules and soluble tubulin in and around the spindle. We found a very sharp decay in the concentration of microtubules at the spindle interface. This is inconsistent with a model in which the activity of nucleators is independent of their association with microtubules but consistent with a model in which microtubule nucleators are only active when bound to pre-existing microtubules. This argues that the activity of microtubule nucleators is greatly enhanced when bound to pre-existing microtubules. Thus, microtubule nucleators are both localized and activated by the microtubules they generate.

  14. Automated high-throughput quantification of mitotic spindle positioning from DIC movies of Caenorhabditis embryos.

    Directory of Open Access Journals (Sweden)

    David Cluet

    Full Text Available The mitotic spindle is a microtubule-based structure that elongates to accurately segregate chromosomes during anaphase. Its position within the cell also dictates the future cell cleavage plan, thereby determining daughter cell orientation within a tissue or cell fate adoption for polarized cells. Therefore, the mitotic spindle ensures at the same time proper cell division and developmental precision. Consequently, spindle dynamics is the matter of intensive research. Among the different cellular models that have been explored, the one-cell stage C. elegans embryo has been an essential and powerful system to dissect the molecular and biophysical basis of spindle elongation and positioning. Indeed, in this large and transparent cell, spindle poles (or centrosomes can be easily detected from simple DIC microscopy by human eyes. To perform quantitative and high-throughput analysis of spindle motion, we developed a computer program ACT for Automated-Centrosome-Tracking from DIC movies of C. elegans embryos. We therefore offer an alternative to the image acquisition and processing of transgenic lines expressing fluorescent spindle markers. Consequently, experiments on large sets of cells can be performed with a simple setup using inexpensive microscopes. Moreover, analysis of any mutant or wild-type backgrounds is accessible because laborious rounds of crosses with transgenic lines become unnecessary. Last, our program allows spindle detection in other nematode species, offering the same quality of DIC images but for which techniques of transgenesis are not accessible. Thus, our program also opens the way towards a quantitative evolutionary approach of spindle dynamics. Overall, our computer program is a unique macro for the image- and movie-processing platform ImageJ. It is user-friendly and freely available under an open-source licence. ACT allows batch-wise analysis of large sets of mitosis events. Within 2 minutes, a single movie is processed

  15. Physical Limits on the Precision of Mitotic Spindle Positioning by Microtubule Pushing forces: Mechanics of mitotic spindle positioning.

    Science.gov (United States)

    Howard, Jonathon; Garzon-Coral, Carlos

    2017-11-01

    Tissues are shaped and patterned by mechanical and chemical processes. A key mechanical process is the positioning of the mitotic spindle, which determines the size and location of the daughter cells within the tissue. Recent force and position-fluctuation measurements indicate that pushing forces, mediated by the polymerization of astral microtubules against- the cell cortex, maintain the mitotic spindle at the cell center in Caenorhabditis elegans embryos. The magnitude of the centering forces suggests that the physical limit on the accuracy and precision of this centering mechanism is determined by the number of pushing microtubules rather than by thermally driven fluctuations. In cells that divide asymmetrically, anti-centering, pulling forces generated by cortically located dyneins, in conjunction with microtubule depolymerization, oppose the pushing forces to drive spindle displacements away from the center. Thus, a balance of centering pushing forces and anti-centering pulling forces localize the mitotic spindles within dividing C. elegans cells. © 2017 The Authors. BioEssays published by Wiley Periodicals, Inc.

  16. A Balance between Nuclear and Cytoplasmic Volumes Controls Spindle Length

    Czech Academy of Sciences Publication Activity Database

    Nováková, Lucia; Kovačovicová, Kristina; Dang-Nguyen, T.; Šodek, Martin; Škultéty, M.; Anger, Martin

    2016-01-01

    Roč. 11, č. 2 (2016), e0149535-e0149535 E-ISSN 1932-6203 R&D Projects: GA ČR GAP502/12/2201 Institutional support: RVO:67985904 Keywords : mitotoc spindle * size * cells Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.806, year: 2016

  17. Discrimination between micronuclei induced by spindle poisons and ...

    African Journals Online (AJOL)

    Discrimination between micronuclei induced by spindle poisons and clastogens by using toad bone marrow polychromatic erythrocytes. ... Egyptian Journal of Biology ... The used chemicals induced high percentages of micronuclei with variable sizes, which clarify the sensitivity of bone marrow cells of Bufo regularis to ...

  18. Timely Endocytosis of Cytokinetic Enzymes Prevents Premature Spindle Breakage during Mitotic Exit.

    Directory of Open Access Journals (Sweden)

    Cheen Fei Chin

    2016-07-01

    Full Text Available Cytokinesis requires the spatio-temporal coordination of membrane deposition and primary septum (PS formation at the division site to drive acto-myosin ring (AMR constriction. It has been demonstrated that AMR constriction invariably occurs only after the mitotic spindle disassembly. It has also been established that Chitin Synthase II (Chs2p neck localization precedes mitotic spindle disassembly during mitotic exit. As AMR constriction depends upon PS formation, the question arises as to how chitin deposition is regulated so as to prevent premature AMR constriction and mitotic spindle breakage. In this study, we propose that cells regulate the coordination between spindle disassembly and AMR constriction via timely endocytosis of cytokinetic enzymes, Chs2p, Chs3p, and Fks1p. Inhibition of endocytosis leads to over accumulation of cytokinetic enzymes during mitotic exit, which accelerates the constriction of the AMR, and causes spindle breakage that eventually could contribute to monopolar spindle formation in the subsequent round of cell division. Intriguingly, the mitotic spindle breakage observed in endocytosis mutants can be rescued either by deleting or inhibiting the activities of, CHS2, CHS3 and FKS1, which are involved in septum formation. The findings from our study highlight the importance of timely endocytosis of cytokinetic enzymes at the division site in safeguarding mitotic spindle integrity during mitotic exit.

  19. Neuroendocrine differentiation of prostate cancer cells

    Czech Academy of Sciences Publication Activity Database

    Souček, Karel; Pernicová, Zuzana; Lincová, Eva; Staršíchová, Andrea; Kozubík, Alois

    2008-01-01

    Roč. 102, č. 5 (2008), s. 393 ISSN 0009-2770. [Mezioborové setkání mladých biologů, biochemiků a chemiků. Konference Sigma-Aldrich /8./. 10.06.2008-13.06.2008, Devět skal - Žďárské vrchy] R&D Projects: GA ČR(CZ) GA204/07/0834; GA ČR(CZ) GA310/07/0961 Institutional research plan: CEZ:AV0Z50040507; CEZ:AV0Z50040702 Keywords : neuroendocrine differentiation * prostate cancer * neuroendocrine-like cells Subject RIV: BO - Biophysics

  20. Differentiated cells are more efficient than adult stem cells for cloning by somatic cell nuclear transfer.

    Science.gov (United States)

    Sung, Li-Ying; Gao, Shaorong; Shen, Hongmei; Yu, Hui; Song, Yifang; Smith, Sadie L; Chang, Ching-Chien; Inoue, Kimiko; Kuo, Lynn; Lian, Jin; Li, Ao; Tian, X Cindy; Tuck, David P; Weissman, Sherman M; Yang, Xiangzhong; Cheng, Tao

    2006-11-01

    Since the creation of Dolly via somatic cell nuclear transfer (SCNT), more than a dozen species of mammals have been cloned using this technology. One hypothesis for the limited success of cloning via SCNT (1%-5%) is that the clones are likely to be derived from adult stem cells. Support for this hypothesis comes from the findings that the reproductive cloning efficiency for embryonic stem cells is five to ten times higher than that for somatic cells as donors and that cloned pups cannot be produced directly from cloned embryos derived from differentiated B and T cells or neuronal cells. The question remains as to whether SCNT-derived animal clones can be derived from truly differentiated somatic cells. We tested this hypothesis with mouse hematopoietic cells at different differentiation stages: hematopoietic stem cells, progenitor cells and granulocytes. We found that cloning efficiency increases over the differentiation hierarchy, and terminally differentiated postmitotic granulocytes yield cloned pups with the greatest cloning efficiency.

  1. Probing stem cell differentiation using atomic force microscopy

    International Nuclear Information System (INIS)

    Liang, Xiaobin; Shi, Xuetao; Ostrovidov, Serge; Wu, Hongkai; Nakajima, Ken

    2016-01-01

    Graphical abstract: - Highlights: • Atomic force microscopy (AFM) was developed to probe stem cell differentiation. • The mechanical properties of stem cells and their ECMs can be used to clearly distinguish specific stem cell-differentiated lineages. • AFM is a facile and useful tool for monitoring stem cell differentiation in a non-invasive manner. - Abstract: A real-time method using atomic force microscopy (AFM) was developed to probe stem cell differentiation by measuring the mechanical properties of cells and the extracellular matrix (ECM). The mechanical properties of stem cells and their ECMs can be used to clearly distinguish specific stem cell-differentiated lineages. It is clear that AFM is a facile and useful tool for monitoring the differentiation of stem cells in a non-invasive manner.

  2. Probing stem cell differentiation using atomic force microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Liang, Xiaobin [Graduate School of Science and Engineering, Tokyo Institute of Technology, Ookayama 2-12-1, Meguro-ku, Tokyo 152-8550 (Japan); Shi, Xuetao, E-mail: mrshixuetao@gmail.com [School of Materials Science and Engineering, South China University of Technology, Guangzhou 510641 (China); Ostrovidov, Serge [WPI-Advanced Institute for Materials Research, Tohoku University, Sendai (Japan); Wu, Hongkai, E-mail: chhkwu@ust.hk [Department of Chemistry & Division of Biomedical Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong (China); Nakajima, Ken [Graduate School of Science and Engineering, Tokyo Institute of Technology, Ookayama 2-12-1, Meguro-ku, Tokyo 152-8550 (Japan)

    2016-03-15

    Graphical abstract: - Highlights: • Atomic force microscopy (AFM) was developed to probe stem cell differentiation. • The mechanical properties of stem cells and their ECMs can be used to clearly distinguish specific stem cell-differentiated lineages. • AFM is a facile and useful tool for monitoring stem cell differentiation in a non-invasive manner. - Abstract: A real-time method using atomic force microscopy (AFM) was developed to probe stem cell differentiation by measuring the mechanical properties of cells and the extracellular matrix (ECM). The mechanical properties of stem cells and their ECMs can be used to clearly distinguish specific stem cell-differentiated lineages. It is clear that AFM is a facile and useful tool for monitoring the differentiation of stem cells in a non-invasive manner.

  3. Unique B cell differentiation profile in tolerant kidney transplant patients.

    Science.gov (United States)

    Chesneau, M; Pallier, A; Braza, F; Lacombe, G; Le Gallou, S; Baron, D; Giral, M; Danger, R; Guerif, P; Aubert-Wastiaux, H; Néel, A; Michel, L; Laplaud, D-A; Degauque, N; Soulillou, J-P; Tarte, K; Brouard, S

    2014-01-01

    Operationally tolerant patients (TOL) display a higher number of blood B cells and transcriptional B cell signature. As they rarely develop an allo-immune response, they could display an abnormal B cell differentiation. We used an in vitro culture system to explore T-dependent differentiation of B cells into plasma cells. B cell phenotype, apoptosis, proliferation, cytokine, immunoglobulin production and markers of differentiation were followed in blood of these patients. Tolerant recipients show a higher frequency of CD20(+) CD24(hi) CD38(hi) transitional and CD20(+) CD38(lo) CD24(lo) naïve B cells compared to patients with stable graft function, correlating with a decreased frequency of CD20(-) CD38(+) CD138(+) differentiated plasma cells, suggestive of abnormal B cell differentiation. B cells from TOL proliferate normally but produce more IL-10. In addition, B cells from tolerant recipients exhibit a defective expression of factors of the end step of differentiation into plasma cells and show a higher propensity for cell death apoptosis compared to patients with stable graft function. This in vitro profile is consistent with down-regulation of B cell differentiation genes and anti-apoptotic B cell genes in these patients in vivo. These data suggest that a balance between B cells producing IL-10 and a deficiency in plasma cells may encourage an environment favorable to the tolerance maintenance. © Copyright 2013 The American Society of Transplantation and the American Society of Transplant Surgeons.

  4. In vitro differentiation of mouse embryonic stem cells into functional ...

    African Journals Online (AJOL)

    Jane

    2011-08-22

    Aug 22, 2011 ... hepatocyte transplantation therapy and toxicity screening in drug discovery. Key words: Embryonic stem cells, hepatic-like cells, in vitro differentiation, sodium butyrate, ... from embryonic stem (ES) cell or induced pluripotent.

  5. [CONDITIONS OF SYNOVIAL MESENCHYMAL STEM CELLS DIFFERENTIATING INTO FIBROCARTILAGE CELLS].

    Science.gov (United States)

    Fu, Peiliang; Cong, Ruijun; Chen, Song; Zhang, Lei; Ding, Zheru; Zhou, Qi; Li, Lintao; Xu, Zhenyu; Wu, Yuli; Wu, Haishan

    2015-01-01

    To explore the conditions of synovial derived mesenchymal stem cells (SMSCs) differentiating into the fibrocartilage cells by using the orthogonal experiment. The synovium was harvested from 5 adult New Zealand white rabbits, and SMSCs were separated by adherence method. The flow cytometry and multi-directional differentiation method were used to identify the SMSCs. The conditions were found from the preliminary experiment and literature review. The missing test was carried out to screen the conditions and then 12 conditions were used for the orthogonal experiment, including transforming growth factor β1 (TGF-β1), bone morphogenic protein 2 (BMP-2), dexamethasone (DEX), proline, ascorbic acid (ASA), pyruvic acid, insulin + transferrin + selenious acid pre-mixed solution (ITS), bovin serum albumin (BSA), basic fibroblast growth factor (bFGF), intermittent hydraulic pressure (IHP), bone morphogenic protein 7 (BMP-7), and insulin-like growth factor (IGF). The L60 (212) orthogonal experiment was designed using the SPSS 18.0 with 2 level conditions and the cells were induced to differentiate on the small intestinal submucosa (SIS)-3D scaffold. The CD151+/CD44+ cells were detected with the flow cytometry and then the differentiation rate was recorded. The immumohistochemical staining, cellular morphology, toluidine blue staining, and semi-quantitative RT-PCR examination for the gene expressions of sex determining region Y (SRY)-box 9 gene (Sox9), aggrecan gene (AGN), collagen type I gene (Col I), collagen type II gene (Col II), collagen type IX gene (Col IX) were used for result confirmation. The differentiation rate was calculated as the product of CD151/CD44+ cells and cells with Col I high expression. The grow curve was detected with the DNA abundance using the PicoGreen Assay. The visual observation and the variances analysis among the variable were used to evaluate the result of the orthogonal experiment, 1 level interaction was considered. The q-test and the

  6. Nanomaterials modulate stem cell differentiation: biological interaction and underlying mechanisms.

    Science.gov (United States)

    Wei, Min; Li, Song; Le, Weidong

    2017-10-25

    Stem cells are unspecialized cells that have the potential for self-renewal and differentiation into more specialized cell types. The chemical and physical properties of surrounding microenvironment contribute to the growth and differentiation of stem cells and consequently play crucial roles in the regulation of stem cells' fate. Nanomaterials hold great promise in biological and biomedical fields owing to their unique properties, such as controllable particle size, facile synthesis, large surface-to-volume ratio, tunable surface chemistry, and biocompatibility. Over the recent years, accumulating evidence has shown that nanomaterials can facilitate stem cell proliferation and differentiation, and great effort is undertaken to explore their possible modulating manners and mechanisms on stem cell differentiation. In present review, we summarize recent progress in the regulating potential of various nanomaterials on stem cell differentiation and discuss the possible cell uptake, biological interaction and underlying mechanisms.

  7. Transplantation and differentiation of donor cells in the cloned pigs

    International Nuclear Information System (INIS)

    Shimada, Arata; Tomii, Ryo; Kano, Koichiro; Nagashima, Hiroshi

    2006-01-01

    The application of nuclear transfer technology is an interesting approach to investigate stem and progenitor cell transplantation therapy. If stem cells are used as a nuclear donor, donor cells can engraft into cloned animals without histocompatible problems. However, it is still uncertain whether donor cells can engraft to cloned animal and differentiate in vivo. To address this problem, we transplanted donor cells to dermal tissues of cloned pigs developed by using preadipocytes as donor cells. Preadipocytes are adipocytic progenitor which can differentiate to mature adipocytes in vitro. We showed that the donor preadipocytes were successfully transplanted into the cloned pigs without immune rejection and they differentiated into mature adipocytes in vivo 3 weeks after transplantation. In contrast, allogenic control preadipocytes, which can differentiate in vitro, did not differentiate in vivo. These results indicate that donor progenitor cells can differentiate in cloned animal

  8. Oligodendrocyte differentiation and implantation : new insights for remyelinating cell therapy

    NARCIS (Netherlands)

    Sher, Falak; Balasubramaniyan, Veerakumar; Boddeke, Erik; Copray, Sjef

    2008-01-01

    Purpose of review Recent research on oligodendrocyte development has yielded new insights on the involvement of morphogens and differentiation factors in oligodendrogenesis. This knowledge has improved strategies to control neural stem cell-derived oligodendrocyte differentiation and functional

  9. Downregulation of rRNA transcription triggers cell differentiation.

    Directory of Open Access Journals (Sweden)

    Yuki Hayashi

    Full Text Available Responding to various stimuli is indispensable for the maintenance of homeostasis. The downregulation of ribosomal RNA (rRNA transcription is one of the mechanisms involved in the response to stimuli by various cellular processes, such as cell cycle arrest and apoptosis. Cell differentiation is caused by intra- and extracellular stimuli and is associated with the downregulation of rRNA transcription as well as reduced cell growth. The downregulation of rRNA transcription during differentiation is considered to contribute to reduced cell growth. However, the downregulation of rRNA transcription can induce various cellular processes; therefore, it may positively regulate cell differentiation. To test this possibility, we specifically downregulated rRNA transcription using actinomycin D or a siRNA for Pol I-specific transcription factor IA (TIF-IA in HL-60 and THP-1 cells, both of which have differentiation potential. The inhibition of rRNA transcription induced cell differentiation in both cell lines, which was demonstrated by the expression of the common differentiation marker CD11b. Furthermore, TIF-IA knockdown in an ex vivo culture of mouse hematopoietic stem cells increased the percentage of myeloid cells and reduced the percentage of immature cells. We also evaluated whether differentiation was induced via the inhibition of cell cycle progression because rRNA transcription is tightly coupled to cell growth. We found that cell cycle arrest without affecting rRNA transcription did not induce differentiation. To the best of our knowledge, our results demonstrate the first time that the downregulation of rRNA levels could be a trigger for the induction of differentiation in mammalian cells. Furthermore, this phenomenon was not simply a reflection of cell cycle arrest. Our results provide a novel insight into the relationship between rRNA transcription and cell differentiation.

  10. Fibroblastic osteosarcoma with epithelioid and squamous differentiation in a dog.

    Science.gov (United States)

    Jenkins, Tiffany L; Agnew, Dalen; Rissi, Daniel R

    2018-04-01

    A fibroblastic osteosarcoma with epithelioid and squamous differentiation in the distal femur of a 9-y-old spayed female Greyhound dog is described. Grossly, the tumor consisted of a pale-white, firm-to-hard mass that replaced the medullary and cortical areas of the distal end of the right femur. Histologically, the mass was composed predominantly of spindle cells admixed with areas of mineralized and non-mineralized osteoid matrix that were surrounded by stellate osteoblasts and scattered multinucleate giant cells, consistent with the diagnosis of a fibroblastic osteosarcoma. In addition, well-demarcated clusters of neoplastic epithelioid cells and foci of squamous differentiation with keratin pearls were present throughout the neoplasm. The spindle cells, epithelioid cells, and areas of squamous differentiation expressed cytoplasmic immunostaining for osteocalcin and osteonectin. The spindle cells and epithelioid cells were also immunopositive for vimentin. Epithelioid cells also expressed occasional cytoplasmic immunostaining for pancytokeratin (PCK) Lu-5, and areas of squamous differentiation were immunoreactive for PCK Lu-5 and high molecular weight CK; these areas were inconsistently immunoreactive for CK 5-6 and immunonegative for low molecular weight CK. Foci of squamous differentiation were not located within blood or lymphatic vessels, given that no immunoreactivity for factor VIII-related antigen was observed around these areas. A thorough autopsy and an evaluation of the medical history excluded a primary carcinoma or other neoplasm elsewhere in the dog. The findings were consistent with a diagnosis of fibroblastic osteosarcoma with epithelioid and squamous differentiation.

  11. Human invariant NKT cell subsets differentially promote differentiation, antibody production, and T cell stimulation by B cells in vitro.

    OpenAIRE

    O'REILLY, VINCENT

    2013-01-01

    PUBLISHED Invariant NK T (iNKT) cells can provide help for B cell activation and Ab production. Because B cells are also capable of cytokine production, Ag presentation, and T cell activation, we hypothesized that iNKT cells will also influence these activities. Furthermore, subsets of iNKT cells based on CD4 and CD8 expression that have distinct functional activities may differentially affect B cell functions. We investigated the effects of coculturing expanded human CD4(+), CD8α(+), and ...

  12. Accuracy of Spindle Units with Hydrostatic Bearings

    Directory of Open Access Journals (Sweden)

    Fedorynenko Dmytro

    2016-06-01

    Full Text Available The work is devoted to the research of precision regularities in a spindle unit by the trajectory of the spindle installed on hydrostatic bearings. The mathematical model of trajectories spindle with lumped parameters that allows to define the position of the spindle with regard the simultaneous influence of design parameters, geometrical deviations ofform, temperature deformation bearing surfaces, the random nature of operational parameters and technical loads of hydrostatic bearings has been developed. Based on the results of numerical modeling the influence of shape errors of bearing surface of hydrostatic bearing on the statistical characteristics of the radius vector trajectories of the spindle by varying the values rotational speed of the spindle and oil pressure in front hydrostatic bearing has been developed. The obtained statistical regularities of precision spindle unit have been confirmed experimentally. It has been shown that an effective way to increase the precision of spindle units is to regulate the size of the gap in hydrostatic spindle bearings. The new design of an adjustable hydrostatic bearing, which can improve the accuracy of regulation size gap has been proposed.

  13. Directional differentiation of chicken embryonic stem cells into ...

    African Journals Online (AJOL)

    Chicken embryonic stem (ES) cells are useful for producing transgenic chickens and preserving genetic material in avian species. In this study, the differentiation potential of chicken ES cells was investigated in vitro. Chicken ES cells were differentiated into osteoblasts cultured for 15 to 21 days in the induction media ...

  14. Primitive human hematopoietic cells give rise to differentially specified daughter cells upon their initial cell division.

    NARCIS (Netherlands)

    Giebel, B.; Zhang, T.; Beckmann, J.; Spanholtz, J.; Wernet, P.; Ho, A.; Punzel, M.

    2006-01-01

    It is often predicted that stem cells divide asymmetrically, creating a daughter cell that maintains the stem-cell capacity, and 1 daughter cell committed to differentiation. While asymmetric stem-cell divisions have been proven to occur in model organisms (eg, in Drosophila), it remains illusive

  15. Multiple Duties for Spindle Assembly Checkpoint Kinases in Meiosis

    Science.gov (United States)

    Marston, Adele L.; Wassmann, Katja

    2017-01-01

    Cell division in mitosis and meiosis is governed by evolutionary highly conserved protein kinases and phosphatases, controlling the timely execution of key events such as nuclear envelope breakdown, spindle assembly, chromosome attachment to the spindle and chromosome segregation, and cell cycle exit. In mitosis, the spindle assembly checkpoint (SAC) controls the proper attachment to and alignment of chromosomes on the spindle. The SAC detects errors and induces a cell cycle arrest in metaphase, preventing chromatid separation. Once all chromosomes are properly attached, the SAC-dependent arrest is relieved and chromatids separate evenly into daughter cells. The signaling cascade leading to checkpoint arrest depends on several protein kinases that are conserved from yeast to man. In meiosis, haploid cells containing new genetic combinations are generated from a diploid cell through two specialized cell divisions. Though apparently less robust, SAC control also exists in meiosis. Recently, it has emerged that SAC kinases have additional roles in executing accurate chromosome segregation during the meiotic divisions. Here, we summarize the main differences between mitotic and meiotic cell divisions, and explain why meiotic divisions pose special challenges for correct chromosome segregation. The less-known meiotic roles of the SAC kinases are described, with a focus on two model systems: yeast and mouse oocytes. The meiotic roles of the canonical checkpoint kinases Bub1, Mps1, the pseudokinase BubR1 (Mad3), and Aurora B and C (Ipl1) will be discussed. Insights into the molecular signaling pathways that bring about the special chromosome segregation pattern during meiosis will help us understand why human oocytes are so frequently aneuploid. PMID:29322045

  16. Multiple Duties for Spindle Assembly Checkpoint Kinases in Meiosis

    Directory of Open Access Journals (Sweden)

    Adele L. Marston

    2017-12-01

    Full Text Available Cell division in mitosis and meiosis is governed by evolutionary highly conserved protein kinases and phosphatases, controlling the timely execution of key events such as nuclear envelope breakdown, spindle assembly, chromosome attachment to the spindle and chromosome segregation, and cell cycle exit. In mitosis, the spindle assembly checkpoint (SAC controls the proper attachment to and alignment of chromosomes on the spindle. The SAC detects errors and induces a cell cycle arrest in metaphase, preventing chromatid separation. Once all chromosomes are properly attached, the SAC-dependent arrest is relieved and chromatids separate evenly into daughter cells. The signaling cascade leading to checkpoint arrest depends on several protein kinases that are conserved from yeast to man. In meiosis, haploid cells containing new genetic combinations are generated from a diploid cell through two specialized cell divisions. Though apparently less robust, SAC control also exists in meiosis. Recently, it has emerged that SAC kinases have additional roles in executing accurate chromosome segregation during the meiotic divisions. Here, we summarize the main differences between mitotic and meiotic cell divisions, and explain why meiotic divisions pose special challenges for correct chromosome segregation. The less-known meiotic roles of the SAC kinases are described, with a focus on two model systems: yeast and mouse oocytes. The meiotic roles of the canonical checkpoint kinases Bub1, Mps1, the pseudokinase BubR1 (Mad3, and Aurora B and C (Ipl1 will be discussed. Insights into the molecular signaling pathways that bring about the special chromosome segregation pattern during meiosis will help us understand why human oocytes are so frequently aneuploid.

  17. Relations between ultrastructure of mitotic spindle and chromosome translocation

    OpenAIRE

    Jadwiga A. Tarkowska

    2014-01-01

    Dividing endosperm cells of Haemanthus katherinae Bak. treated with an 0.25 per cent mixture of water-soluble glycosides from Nerium oleander were insepected in a light microscope (LM) and severe disturbances were found in all phases of mitosis. The same cells were observed in the electron microscope (EM) and relations were noted and analysed between the chromosome arrangement and the submicroscopic structure of the mitotuc spindle. The successive steps in the disintegration of the formed spi...

  18. Human dental pulp stem cells derived from cryopreserved dental pulp tissues of vital extracted teeth with disease demonstrate hepatic-like differentiation.

    Science.gov (United States)

    Chen, Y K; Huang, Anderson H C; Chan, Anthony W S; Lin, L M

    2016-06-01

    Reviewing the literature, hepatic differentiation of human dental pulp stem cells (hDPSCs) from cryopreserved dental pulp tissues of vital extracted teeth with disease has not been studied. This study is aimed to evaluate the hypothesis that hDPSCs from cryopreserved dental pulp tissues of vital extracted teeth with disease could possess potential hepatic differentiation. Forty vital extracted teeth with disease recruited for hDPSCs isolation, stem cell characterization and hepatic differentiation were randomly and equally divided into group A (liquid nitrogen-stored dental pulp tissues) and group B (freshly derived dental pulp tissues). Samples of hDPSCs isolated from groups A and B but without hepatic growth factors formed negative controls. A well-differentiated hepatocellular carcinoma cell line was employed as a positive control. All the isolated hDPSCs from groups A and B showed hepatic-like differentiation with morphological change from a spindle-shaped to a polygonal shape and normal karyotype. Differentiated hDPSCs and the positive control expressed hepatic metabolic function genes and liver-specific genes. Glycogen storage of differentiated hDPSCs was noted from day 7 of differentiation-medium culture. Positive immunofluorescence staining of low-density lipoprotein and albumin was observed from day 14 of differentiation-medium culture; urea production in the medium was noted from week 6. No hepatic differentiation was observed for any of the samples of the negative controls. We not only demonstrated the feasibility of hepatic-like differentiation of hDPSCs from cryopreserved dental pulp tissues of vital extracted teeth with disease but also indicated that the differentiated cells possessed normal karyotype and were functionally close to normal hepatic-like cells. Copyright © 2013 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  19. Spontaneous Differentiation of Human Mesenchymal Stem Cells on Poly-Lactic-Co-Glycolic Acid Nano-Fiber Scaffold.

    Directory of Open Access Journals (Sweden)

    Koshiro Sonomoto

    Full Text Available Mesenchymal stem cells (MSCs have immunosuppressive activity and can differentiate into bone and cartilage; and thus seem ideal for treatment of rheumatoid arthritis (RA. Here, we investigated the osteogenesis and chondrogenesis potentials of MSCs seeded onto nano-fiber scaffolds (NFs in vitro and possible use for the repair of RA-affected joints.MSCs derived from healthy donors and patients with RA or osteoarthritis (OA were seeded on poly-lactic-glycolic acid (PLGA electrospun NFs and cultured in vitro.Healthy donor-derived MSCs seeded onto NFs stained positive with von Kossa at Day 14 post-stimulation for osteoblast differentiation. Similarly, MSCs stained positive with Safranin O at Day 14 post-stimulation for chondrocyte differentiation. Surprisingly, even cultured without any stimulation, MSCs expressed RUNX2 and SOX9 (master regulators of bone and cartilage differentiation at Day 7. Moreover, MSCs stained positive for osteocalcin, a bone marker, and simultaneously also with Safranin O at Day 14. On Day 28, the cell morphology changed from a spindle-like to an osteocyte-like appearance with processes, along with the expression of dentin matrix protein-1 (DMP-1 and matrix extracellular phosphoglycoprotein (MEPE, suggesting possible differentiation of MSCs into osteocytes. Calcification was observed on Day 56. Expression of osteoblast and chondrocyte differentiation markers was also noted in MSCs derived from RA or OA patients seeded on NFs. Lactic acid present in NFs potentially induced MSC differentiation into osteoblasts.Our PLGA scaffold NFs induced MSC differentiation into bone and cartilage. NFs induction process resembled the procedure of endochondral ossification. This finding indicates that the combination of MSCs and NFs is a promising therapeutic technique for the repair of RA or OA joints affected by bone and cartilage destruction.

  20. Symbiotic Cell Differentiation and Cooperative Growth in Multicellular Aggregates.

    Directory of Open Access Journals (Sweden)

    Jumpei F Yamagishi

    2016-10-01

    Full Text Available As cells grow and divide under a given environment, they become crowded and resources are limited, as seen in bacterial biofilms and multicellular aggregates. These cells often show strong interactions through exchanging chemicals, as evident in quorum sensing, to achieve mutualism and division of labor. Here, to achieve stable division of labor, three characteristics are required. First, isogenous cells differentiate into several types. Second, this aggregate of distinct cell types shows better growth than that of isolated cells without interaction and differentiation, by achieving division of labor. Third, this cell aggregate is robust with respect to the number distribution of differentiated cell types. Indeed, theoretical studies have thus far considered how such cooperation is achieved when the ability of cell differentiation is presumed. Here, we address how cells acquire the ability of cell differentiation and division of labor simultaneously, which is also connected with the robustness of a cell society. For this purpose, we developed a dynamical-systems model of cells consisting of chemical components with intracellular catalytic reaction dynamics. The reactions convert external nutrients into internal components for cellular growth, and the divided cells interact through chemical diffusion. We found that cells sharing an identical catalytic network spontaneously differentiate via induction from cell-cell interactions, and then achieve division of labor, enabling a higher growth rate than that in the unicellular case. This symbiotic differentiation emerged for a class of reaction networks under the condition of nutrient limitation and strong cell-cell interactions. Then, robustness in the cell type distribution was achieved, while instability of collective growth could emerge even among the cooperative cells when the internal reserves of products were dominant. The present mechanism is simple and general as a natural consequence of

  1. Non-genetic heterogeneity, criticality and cell differentiation.

    Science.gov (United States)

    Pal, Mainak; Ghosh, Sayantari; Bose, Indrani

    2014-11-27

    The different cell types in a living organism acquire their identity through the process of cell differentiation in which multipotent progenitor cells differentiate into distinct cell types. Experimental evidence and analysis of large-scale microarray data establish the key role played by a two-gene motif in cell differentiation in a number of cell systems. The two genes express transcription factors which repress each other's expression and autoactivate their own production. A number of theoretical models have recently been proposed based on the two-gene motif to provide a physical understanding of how cell differentiation occurs. In this paper, we study a simple model of cell differentiation which assumes no cooperativity in the regulation of gene expression by the transcription factors. The latter repress each other's activity directly through DNA binding and indirectly through the formation of heterodimers. We specifically investigate how deterministic processes combined with stochasticity contribute in bringing about cell differentiation. The deterministic dynamics of our model give rise to a supercritical pitchfork bifurcation from an undifferentiated stable steady state to two differentiated stable steady states. The stochastic dynamics of our model are studied using the approaches based on the Langevin equations and the linear noise approximation. The simulation results provide a new physical understanding of recent experimental observations. We further propose experimental measurements of quantities like the variance and the lag-1 autocorrelation function in protein fluctuations as the early signatures of an approaching bifurcation point in the cell differentiation process.

  2. Sequential activities of Dynein, Mud and Asp in centrosome-spindle coupling maintain centrosome number upon mitosis.

    Science.gov (United States)

    Bosveld, Floris; Ainslie, Anna; Bellaïche, Yohanns

    2017-10-15

    Centrosomes nucleate microtubules and are tightly coupled to the bipolar spindle to ensure genome integrity, cell division orientation and centrosome segregation. While the mechanisms of centrosome-dependent microtubule nucleation and bipolar spindle assembly have been the focus of numerous works, less is known about the mechanisms ensuring the centrosome-spindle coupling. The conserved NuMA protein (Mud in Drosophila ) is best known for its role in spindle orientation. Here, we analyzed the role of Mud and two of its interactors, Asp and Dynein, in the regulation of centrosome numbers in Drosophila epithelial cells. We found that Dynein and Mud mainly initiate centrosome-spindle coupling prior to nuclear envelope breakdown (NEB) by promoting correct centrosome positioning or separation, while Asp acts largely independently of Dynein and Mud to maintain centrosome-spindle coupling. Failure in the centrosome-spindle coupling leads to mis-segregation of the two centrosomes into one daughter cell, resulting in cells with supernumerary centrosomes during subsequent divisions. Altogether, we propose that Dynein, Mud and Asp operate sequentially during the cell cycle to ensure efficient centrosome-spindle coupling in mitosis, thereby preventing centrosome mis-segregation to maintain centrosome number. © 2017. Published by The Company of Biologists Ltd.

  3. Correlation between membrane fluidity cellular development and stem cell differentiation

    KAUST Repository

    Noutsi, Bakiza Kamal

    2016-01-01

    Cell membranes are made up of a complex structure of lipids and proteins that diffuse laterally giving rise to what we call membrane fluidity. During cellular development, such as neuronal differentiation, cell membranes undergo dramatic structural

  4. Warts phosphorylates mud to promote pins-mediated mitotic spindle orientation in Drosophila, independent of Yorkie.

    Science.gov (United States)

    Dewey, Evan B; Sanchez, Desiree; Johnston, Christopher A

    2015-11-02

    Multicellular animals have evolved conserved signaling pathways that translate cell polarity cues into mitotic spindle positioning to control the orientation of cell division within complex tissue structures. These oriented cell divisions are essential for the development of cell diversity and the maintenance of tissue homeostasis. Despite intense efforts, the molecular mechanisms that control spindle orientation remain incompletely defined. Here, we describe a role for the Hippo (Hpo) kinase complex in promoting Partner of Inscuteable (Pins)-mediated spindle orientation. Knockdown of Hpo, Salvador (Sav), or Warts (Wts) each result in a partial loss of spindle orientation, a phenotype previously described following loss of the Pins-binding protein Mushroom body defect (Mud). Similar to orthologs spanning yeast to mammals, Wts kinase localizes to mitotic spindle poles, a prominent site of Mud localization. Wts directly phosphorylates Mud in vitro within its C-terminal coiled-coil domain. This Mud coiled-coil domain directly binds the adjacent Pins-binding domain to dampen the Pins/Mud interaction, and Wts-mediated phosphorylation uncouples this intramolecular Mud interaction. Loss of Wts prevents cortical Pins/Mud association without affecting Mud accumulation at spindle poles, suggesting phosphorylation acts as a molecular switch to specifically activate cortical Mud function. Finally, loss of Wts in Drosophila imaginal disc epithelial cells results in diminished cortical Mud and defective planar spindle orientation. Our results provide new insights into the molecular basis for dynamic regulation of the cortical Pins/Mud spindle positioning complex and highlight a novel link with an essential, evolutionarily conserved cell proliferation pathway. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Clathrin is spindle-associated but not essential for mitosis.

    Directory of Open Access Journals (Sweden)

    Joana Borlido

    Full Text Available Clathrin is a multimeric protein involved in vesicle coat assembly. Recently clathrin distribution was reported to change during the cell cycle and was found to associate with the mitotic spindle. Here we test whether the recruitment of clathrin to the spindle is indicative of a critical functional contribution to mitosis.Previously a chicken pre-B lymphoma cell line (DKO-R was developed in which the endogenous clathrin heavy chain alleles were replaced with the human clathrin heavy chain under the control of a tetracycline-regulatable promoter. Receptor-mediated and fluid-phase endocytosis were significantly inhibited in this line following clathrin knockout, and we used this to explore the significance of clathrin heavy chain expression for cell cycle progression. We confirmed using confocal microscopy that clathrin colocalised with tubulin at mitotic spindles. Using a propidium iodide flow cytometric assay we found no statistical difference in the cell cycle distribution of the knockout cells versus the wild-type. Additionally, we showed that the ploidy and the recovery kinetics following cell cycle arrest with nocodazole were unchanged by repressing clathrin heavy chain expression.We conclude that the association of clathrin with the mitotic spindle and the contribution of clathrin to endocytosis are evolutionarily conserved. However we find that the contribution of clathrin to mitosis is less robust and dependent on cellular context. In other cell-lines silencing RNA has been used by others to knockdown clathrin expression resulting in an increase in the mitotic index of the cells. We show an effect on the G2/M phase population of clathrin knockdown in HEK293 cells but show that repressing clathrin expression in the DKO-R cell-line has no effect on the size of this population. Consequently this work highlights the need for a more detailed molecular understanding of the recruitment and function of clathrin at the spindle, since the

  6. Membrane glycoproteins of differentiating skeletal muscle cells

    International Nuclear Information System (INIS)

    Miller, K.R.; Remy, C.N.; Smith, P.B.

    1987-01-01

    The composition of N-linked glycoprotein oligosaccharides was studied in myoblasts and myotubes of the C2 muscle cell line. Oligosaccharides were radioactively labelled for 15 hr with [ 3 H] mannose and plasma membranes isolated. Ten glycopeptides were detected by SDS-PAGE and fluorography. The extent of labelling was 4-6 fold greater in myoblasts vs myotubes. A glycopeptide of Mr > 100,000 was found exclusively in myoblast membranes. Lectin chromatography revealed that the proportion of tri-, tetranntenary, biantennary and high mannose chains was similar throughout differentiation. The high mannose chain fraction was devoid of hybrid chains. The major high mannose chain contained nine mannose residues. The higher level of glycopeptide labelling in myoblasts vs myotubes corresponded to a 5-fold greater rate of protein synthesis. Pulse-chase experiments were used to follow the synthesis of the Dol-oligosaccharides. Myoblasts and myotubes labelled equivalently the glucosylated tetradecasaccharide but myoblasts labelled the smaller intermediates 3-4 greater than myotubes. Myoblasts also exhibited a 2-3 fold higher Dol-P dependent glycosyl transferase activity for chain elongation and Dol-sugar synthesis. Together these results show that the degree of protein synthesis and level of Dol-P are contributing factors in the higher capacity of myoblasts to produce N-glycoproteins compared to myotubes

  7. Differential marker expression by cultures rich in mesenchymal stem cells

    Science.gov (United States)

    2013-01-01

    Background Mesenchymal stem cells have properties that make them amenable to therapeutic use. However, the acceptance of mesenchymal stem cells in clinical practice requires standardized techniques for their specific isolation. To date, there are no conclusive marker (s) for the exclusive isolation of mesenchymal stem cells. Our aim was to identify markers differentially expressed between mesenchymal stem cell and non-stem cell mesenchymal cell cultures. We compared and contrasted the phenotype of tissue cultures in which mesenchymal stem cells are rich and rare. By initially assessing mesenchymal stem cell differentiation, we established that bone marrow and breast adipose cultures are rich in mesenchymal stem cells while, in our hands, foreskin fibroblast and olfactory tissue cultures contain rare mesenchymal stem cells. In particular, olfactory tissue cells represent non-stem cell mesenchymal cells. Subsequently, the phenotype of the tissue cultures were thoroughly assessed using immuno-fluorescence, flow-cytometry, proteomics, antibody arrays and qPCR. Results Our analysis revealed that all tissue cultures, regardless of differentiation potential, demonstrated remarkably similar phenotypes. Importantly, it was also observed that common mesenchymal stem cell markers, and fibroblast-associated markers, do not discriminate between mesenchymal stem cell and non-stem cell mesenchymal cell cultures. Examination and comparison of the phenotypes of mesenchymal stem cell and non-stem cell mesenchymal cell cultures revealed three differentially expressed markers – CD24, CD108 and CD40. Conclusion We indicate the importance of establishing differential marker expression between mesenchymal stem cells and non-stem cell mesenchymal cells in order to determine stem cell specific markers. PMID:24304471

  8. Schwann cells promote neuronal differentiation of bone marrow ...

    African Journals Online (AJOL)

    It has been suggested that the BMSCs have the capacity to differentiate into neurons under specific experimental conditions, using chemical factors. In this study, we showed that BMSCs can be induced to differentiate into neuron-like cells when they are co-cultured with Schwann cells by Brdu pulse label technology.

  9. Isolation and Osteogenic Differentiation of Rat Periosteum-derived Cells

    OpenAIRE

    Declercq, Heidi Andrea; De Ridder, Leo Isabelle; Cornelissen, Maria Jozefa

    2005-01-01

    Selection of appropriate cultures having an osteogenic potential is a necessity if cell/biomaterial interactions are studied in long-term cultures. Osteoblastic cells derived from rat long bones or calvaria have the disadvantage of being in an advanced differentiation stage which results in terminal differentiation within 21 days. In this regard, less differentiated periosteum-derived osteoprogenitors could be more suitable.

  10. Relations between ultrastructure of mitotic spindle and chromosome translocation

    Directory of Open Access Journals (Sweden)

    Jadwiga A. Tarkowska

    2014-01-01

    Full Text Available Dividing endosperm cells of Haemanthus katherinae Bak. treated with an 0.25 per cent mixture of water-soluble glycosides from Nerium oleander were insepected in a light microscope (LM and severe disturbances were found in all phases of mitosis. The same cells were observed in the electron microscope (EM and relations were noted and analysed between the chromosome arrangement and the submicroscopic structure of the mitotuc spindle. The successive steps in the disintegration of the formed spindle are described: fragmentatiun of all microtubules (MTs starting from the poles, disappearance of non-kinetachore MTs and further the external MTs of the kineto,chore bundle. The central (internal parallel ones remain the longest at the kinerf,ochares. Oleander glycosides cause disintegration of the existing MTs and prevent formation of new ones. The causes of restitution transformations in the successive phases of mitosis are discussed.

  11. Demethylating agent, 5-azacytidine, reverses differentiation of embryonic stem cells

    International Nuclear Information System (INIS)

    Tsuji-Takayama, Kazue; Inoue, Toshiya; Ijiri, Yoshihiro; Otani, Takeshi; Motoda, Ryuichi; Nakamura, Shuji; Orita, Kunzo

    2004-01-01

    The de novo methylation activity is essential for embryonic development as well as embryonic stem (ES) cell differentiation, where the intensive and extensive DNA methylation was detected. In this study, we investigated the effects of a demethylating agent, 5-azacytidine (5-AzaC), on differentiated ES cells in order to study the possibility of reversing the differentiation process. We first induced differentiation of ES cells by forming embryoid bodies, and then the cells were treated with 5-AzaC. The cells showed some undifferentiated features such as stem cell-like morphology with unclear cell-to-cell boundary and proliferative responsiveness to LIF. Moreover, 5-AzaC increased the expressions of ES specific markers, SSEA-1, and alkaline phosphatase activity as well as ES specific genes, Oct4, Nanog, and Sox2. We also found that 5-AzaC demethylated the promoter region of H19 gene, a typical methylated gene during embryonic differentiation. These results indicate that 5-AzaC reverses differentiation state of ES cells through its DNA demethylating activity to differentiation related genes

  12. Hepatic differentiation potential of commercially available human mesenchymal stem cells.

    Science.gov (United States)

    Ong, Shin-Yeu; Dai, Hui; Leong, Kam W

    2006-12-01

    The ready availability and low immunogenicity of commercially available mesenchymal stem cells (MSC) render them a potential cell source for the development of therapeutic products. With cell source a major bottleneck in hepatic tissue engineering, we investigated whether commercially available human MSC (hMSC) can transdifferentiate into the hepatic lineage. Based on previous studies that find rapid gain of hepatic genes in bone marrow-derived stem cells cocultured with liver tissue, we used a similar approach to drive hepatic differentiation by coculturing the hMSC with rat livers treated or untreated with gadolinium chloride (GdCl(3)). After a 24-hour coculture period with liver tissue injured by GdCl(3) in a Transwell configuration, approximately 34% of the cells differentiated into albumin-expressing cells. Cocultured cells were subsequently maintained with growth factors to complete the hepatic differentiation. Cocultured cells expressed more hepatic gene markers, and had higher metabolic functions and P450 activity than cells that were only differentiated with growth factors. In conclusion, commercially available hMSC do show hepatic differentiation potential, and a liver microenvironment in culture can provide potent cues to accelerate and deepen the differentiation. The ability to generate hepatocyte-like cells from a commercially available cell source would find interesting applications in liver tissue engineering.

  13. Two pore channel 2 differentially modulates neural differentiation of mouse embryonic stem cells.

    Directory of Open Access Journals (Sweden)

    Zhe-Hao Zhang

    Full Text Available Nicotinic acid adenine dinucleotide phosphate (NAADP is an endogenous Ca(2+ mobilizing nucleotide presented in various species. NAADP mobilizes Ca(2+ from acidic organelles through two pore channel 2 (TPC2 in many cell types and it has been previously shown that NAADP can potently induce neuronal differentiation in PC12 cells. Here we examined the role of TPC2 signaling in the neural differentiation of mouse embryonic stem (ES cells. We found that the expression of TPC2 was markedly decreased during the initial ES cell entry into neural progenitors, and the levels of TPC2 gradually rebounded during the late stages of neurogenesis. Correspondingly, TPC2 knockdown accelerated mouse ES cell differentiation into neural progenitors but inhibited these neural progenitors from committing to neurons. Overexpression of TPC2, on the other hand, inhibited mouse ES cell from entering the early neural lineage. Interestingly, TPC2 knockdown had no effect on the differentiation of astrocytes and oligodendrocytes of mouse ES cells. Taken together, our data indicate that TPC2 signaling plays a temporal and differential role in modulating the neural lineage entry of mouse ES cells, in that TPC2 signaling inhibits ES cell entry to early neural progenitors, but is required for late neuronal differentiation.

  14. NOV/CCN3 impairs muscle cell commitment and differentiation

    International Nuclear Information System (INIS)

    Calhabeu, Frederico; Lafont, Jerome; Le Dreau, Gwenvael; Laurent, Maryvonne; Kazazian, Chantal; Schaeffer, Laurent; Martinerie, Cecile; Dubois, Catherine

    2006-01-01

    NOV (nephroblastoma overexpressed) is a member of a family of proteins which encodes secreted matrix-associated proteins. NOV is expressed during development in dermomyotome and limb buds, but its functions are still poorly defined. In order to understand the role of NOV in myogenic differentiation, C2C12 cells overexpressing NOV (C2-NOV) were generated. These cells failed to engage into myogenic differentiation, whereas they retained the ability to differentiate into osteoblasts. In differentiating conditions, C2-NOV cells remained proliferative, failed to express differentiation markers and lost their ability to form myotubes. Inhibition of differentiation by NOV was also observed with human primary muscle cells. Further examination of C2-NOV cells revealed a strong downregulation of the myogenic determination genes MyoD and Myf5 and of IGF-II expression. MyoD forced expression in C2-NOV was sufficient to restore differentiation and IGF-II induction whereas 10 -6 M insulin treatment had no effects. NOV therefore acts upstream of MyoD and does not affect IGF-II induction and signaling. HES1, a target of Notch, previously proposed to mediate NOV action, was not implicated in the inhibition of differentiation. We propose that NOV is a specific cell fate regulator in the myogenic lineage, acting negatively on key myogenic genes thus controlling the transition from progenitor cells to myoblasts

  15. Diclofenac and triamcinolone acetonide impair tenocytic differentiation and promote adipocytic differentiation of mesenchymal stem cells.

    Science.gov (United States)

    Fredriksson, Maritha; Li, Yan; Stålman, Anders; Haldosén, Lars-Arne; Felländer-Tsai, Li

    2013-09-02

    Tendinopathies are often empirically treated with oral/topical nonsteroidal anti-inflammatory medications and corticosteroid injections despite their unclear effects on tendon regeneration. Recent studies indicate that tendon progenitors exhibit stem cell-like properties, i.e., differentiation to osteoblasts, adipocytes, and chondrocytes, in addition to tenocytes. Our present study aims at understanding the effects of triamcinolone acetonide and diclofenac on tenocytic differentiation of mesenchymal stem cells. The murine fibroblast C3H10T1/2 cell line was induced to tenocytic differentiation by growth differentiation factor-7. Cell proliferation and differentiation with the exposure of different concentrations of triamcinolone acetonide and diclofenac were measured by WST-1 assay and real-time polymerase chain reaction analysis, respectively. Cell proliferation was decreased in a concentration-dependent manner when exposed to triamcinolone acetonide and diclofenac. In addition to tenocytic differentiation, adipocyte formation was observed, both at gene expression and microscopic level, when the cells were exposed to triamcinolone acetonide or high concentrations of diclofenac. Our results indicate that triamcinolone acetonide and diclofenac might alter mesenchymal stem cell differentiation in a nonfavorable way regarding tendon regeneration; therefore, these medications should be used with more caution clinically.

  16. Sleep spindle density in narcolepsy

    DEFF Research Database (Denmark)

    Christensen, Julie Anja Engelhard; Nikolic, Miki; Hvidtfelt, Mathias

    2017-01-01

    BACKGROUND: Patients with narcolepsy type 1 (NT1) show alterations in sleep stage transitions, rapid-eye-movement (REM) and non-REM sleep due to the loss of hypocretinergic signaling. However, the sleep microstructure has not yet been evaluated in these patients. We aimed to evaluate whether...... the sleep spindle (SS) density is altered in patients with NT1 compared to controls and patients with narcolepsy type 2 (NT2). METHODS: All-night polysomnographic recordings from 28 NT1 patients, 19 NT2 patients, 20 controls (C) with narcolepsy-like symptoms, but with normal cerebrospinal fluid hypocretin...... levels and multiple sleep latency tests, and 18 healthy controls (HC) were included. Unspecified, slow, and fast SS were automatically detected, and SS densities were defined as number per minute and were computed across sleep stages and sleep cycles. The between-cycle trends of SS densities in N2...

  17. Vascular Mural Cells Promote Noradrenergic Differentiation of Embryonic Sympathetic Neurons

    Directory of Open Access Journals (Sweden)

    Vitor Fortuna

    2015-06-01

    Full Text Available The sympathetic nervous system controls smooth muscle tone and heart rate in the cardiovascular system. Postganglionic sympathetic neurons (SNs develop in close proximity to the dorsal aorta (DA and innervate visceral smooth muscle targets. Here, we use the zebrafish embryo to ask whether the DA is required for SN development. We show that noradrenergic (NA differentiation of SN precursors temporally coincides with vascular mural cell (VMC recruitment to the DA and vascular maturation. Blocking vascular maturation inhibits VMC recruitment and blocks NA differentiation of SN precursors. Inhibition of platelet-derived growth factor receptor (PDGFR signaling prevents VMC differentiation and also blocks NA differentiation of SN precursors. NA differentiation is normal in cloche mutants that are devoid of endothelial cells but have VMCs. Thus, PDGFR-mediated mural cell recruitment mediates neurovascular interactions between the aorta and sympathetic precursors and promotes their noradrenergic differentiation.

  18. Vascular Mural Cells Promote Noradrenergic Differentiation of Embryonic Sympathetic Neurons.

    Science.gov (United States)

    Fortuna, Vitor; Pardanaud, Luc; Brunet, Isabelle; Ola, Roxana; Ristori, Emma; Santoro, Massimo M; Nicoli, Stefania; Eichmann, Anne

    2015-06-23

    The sympathetic nervous system controls smooth muscle tone and heart rate in the cardiovascular system. Postganglionic sympathetic neurons (SNs) develop in close proximity to the dorsal aorta (DA) and innervate visceral smooth muscle targets. Here, we use the zebrafish embryo to ask whether the DA is required for SN development. We show that noradrenergic (NA) differentiation of SN precursors temporally coincides with vascular mural cell (VMC) recruitment to the DA and vascular maturation. Blocking vascular maturation inhibits VMC recruitment and blocks NA differentiation of SN precursors. Inhibition of platelet-derived growth factor receptor (PDGFR) signaling prevents VMC differentiation and also blocks NA differentiation of SN precursors. NA differentiation is normal in cloche mutants that are devoid of endothelial cells but have VMCs. Thus, PDGFR-mediated mural cell recruitment mediates neurovascular interactions between the aorta and sympathetic precursors and promotes their noradrenergic differentiation. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

  19. Early stage differentiation of thallus cells of Porphyra haitanensis (Rhodophyta)

    Science.gov (United States)

    Wang, Sujuan; Sun, Yunlong; Lu, Anming; Wang, Guangyuan

    1987-09-01

    The early stage differentiation of thallus cells of Porphyra haitanensis T. J. Chang et B. F. Zheng was studied. Protoplasts or single cells were isolated from the blades using enzyme mixture comprising 2% sea snail gut enzyme and 1% cellulase. The isolated protoplasts or single cells were incubated in the MES medium. The cell differentiations were examined under the microscope at intervals after incubation. Four types of cell differentiation, namely, normal, abnormal, carposporangial and spermatorangial, and rhizoidal types, were observed. Since normal cell differentiations occur mostly in small thalli 50 mm in length and middle portions of big thalli 200 mm in length, it is essential to select tissues from these two kinds of thalli essential for commercial production.

  20. Differentiation of stem cells upon deprivation of exogenous FGF2

    DEFF Research Database (Denmark)

    Kjartansdóttir, Kristín Rós; Gabrielsen, Anette; Reda, Ahmed

    2012-01-01

    Establishing a model for in vitro differentiation of human embryonic stem cells (hESCs) towards the germ cell lineage could be used to identify molecular mechanisms behind germ cell differentiation that may help in understanding human infertility. Here, we evaluate whether a lack of exogenous...... fibroblast growth factor 2 (FGF2) is supporting spontaneous differentiation of hESCs cultured on human foreskin fibroblast (hFF) monolayers towards germ cell lineage. Additionally to depriving the hESCs of exogenous FGF2, cells were stimulated with all-trans retinoic acid (ATRA). To get a more comprehensive...... impression on effects of removal of FGF2 and stimulation with ATRA, we combined the results of three cell lines for each experimental setting. When combining gene expression profiles of three cell lines for 96 genes, only 6 genes showed a significant up-regulation in all cell lines, when no FGF2 was added...

  1. Epigenetic control of CD8+ T cell differentiation.

    Science.gov (United States)

    Henning, Amanda N; Roychoudhuri, Rahul; Restifo, Nicholas P

    2018-05-01

    Upon stimulation, small numbers of naive CD8 + T cells proliferate and differentiate into a variety of memory and effector cell types. CD8 + T cells can persist for years and kill tumour cells and virally infected cells. The functional and phenotypic changes that occur during CD8 + T cell differentiation are well characterized, but the epigenetic states that underlie these changes are incompletely understood. Here, we review the epigenetic processes that direct CD8 + T cell differentiation and function. We focus on epigenetic modification of DNA and associated histones at genes and their regulatory elements. We also describe structural changes in chromatin organization that affect gene expression. Finally, we examine the translational potential of epigenetic interventions to improve CD8 + T cell function in individuals with chronic infections and cancer.

  2. In vitro germ cell differentiation from cynomolgus monkey embryonic stem cells.

    Directory of Open Access Journals (Sweden)

    Kaori Yamauchi

    Full Text Available BACKGROUND: Mouse embryonic stem (ES cells can differentiate into female and male germ cells in vitro. Primate ES cells can also differentiate into immature germ cells in vitro. However, little is known about the differentiation markers and culture conditions for in vitro germ cell differentiation from ES cells in primates. Monkey ES cells are thus considered to be a useful model to study primate gametogenesis in vitro. Therefore, in order to obtain further information on germ cell differentiation from primate ES cells, this study examined the ability of cynomolgus monkey ES cells to differentiate into germ cells in vitro. METHODS AND FINDINGS: To explore the differentiation markers for detecting germ cells differentiated from ES cells, the expression of various germ cell marker genes was examined in tissues and ES cells of the cynomolgus monkey (Macaca fascicularis. VASA is a valuable gene for the detection of germ cells differentiated from ES cells. An increase of VASA expression was observed when differentiation was induced in ES cells via embryoid body (EB formation. In addition, the expression of other germ cell markers, such as NANOS and PIWIL1 genes, was also up-regulated as the EB differentiation progressed. Immunocytochemistry identified the cells expressing stage-specific embryonic antigen (SSEA 1, OCT-4, and VASA proteins in the EBs. These cells were detected in the peripheral region of the EBs as specific cell populations, such as SSEA1-positive, OCT-4-positive cells, OCT-4-positive, VASA-positive cells, and OCT-4-negative, VASA-positive cells. Thereafter, the effect of mouse gonadal cell-conditioned medium and growth factors on germ cell differentiation from monkey ES cells was examined, and this revealed that the addition of BMP4 to differentiating ES cells increased the expression of SCP1, a meiotic marker gene. CONCLUSION: VASA is a valuable gene for the detection of germ cells differentiated from ES cells in monkeys, and the

  3. Id2 reinforces TH1 cell differentiation and inhibits E2A to repress TFH cell differentiation

    Science.gov (United States)

    Shaw, Laura A.; Bélanger, Simon; Omilusik, Kyla D.; Cho, Sunglim; Scott-Browne, James P.; Nance, J. Philip; Goulding, John; Lasorella, Anna; Lu, Li-Fan; Crotty, Shane; Goldrath, Ananda W.

    2016-01-01

    Differentiation of T helper (TH) effector subsets is critical for host protection. E protein transcription factors and Id proteins are important arbiters of T cell development, but their role in differentiation of TH1 and TFH cells is not well understood. TH1 cells showed robust Id2 expression compared to TFH cells, and RNAi depletion of Id2 increased TFH cell frequencies. Further, TH1 cell differentiation was blocked by Id2 deficiency, leading to E protein-dependent accumulation of effector cells with mixed characteristics during viral infection and severely impaired generation of TH1 cells following Toxoplasma gondii infection. The TFH-defining transcriptional repressor Bcl6 bound the Id2 locus, providing a mechanism for the bimodal Id2 expression and reciprocal development of TH1 and TFH cell fates. PMID:27213691

  4. Hypercholesterolemia Induces Differentiation of Regulatory T Cells in the Liver.

    Science.gov (United States)

    Mailer, Reiner K W; Gisterå, Anton; Polyzos, Konstantinos A; Ketelhuth, Daniel F J; Hansson, Göran K

    2017-05-26

    The liver is the central organ that responds to dietary cholesterol intake and facilitates the release and clearance of lipoprotein particles. Persistent hypercholesterolemia leads to immune responses against lipoprotein particles that drive atherosclerosis. However, the effect of hypercholesterolemia on hepatic T-cell differentiation remains unknown. To investigate hepatic T-cell subsets upon hypercholesterolemia. We observed that hypercholesterolemia elevated the intrahepatic regulatory T (Treg) cell population and increased the expression of transforming growth factor-β1 in the liver. Adoptive transfer experiments revealed that intrahepatically differentiated Treg cells relocated to the inflamed aorta in atherosclerosis-prone low-density lipoprotein receptor deficient ( Ldlr -/- ) mice. Moreover, hypercholesterolemia induced the differentiation of intrahepatic, but not intrasplenic, Th17 cells in wild-type mice, whereas the disrupted liver homeostasis in hypercholesterolemic Ldlr -/- mice led to intrahepatic Th1 cell differentiation and CD11b + CD11c + leukocyte accumulation. Our results elucidate a new mechanism that controls intrahepatic T-cell differentiation during atherosclerosis development and indicates that intrahepatically differentiated T cells contribute to the CD4 + T-cell pool in the atherosclerotic aorta. © 2017 American Heart Association, Inc.

  5. The Physics of the Metaphase Spindle.

    Science.gov (United States)

    Oriola, David; Needleman, Daniel J; Brugués, Jan

    2018-05-20

    The assembly of the mitotic spindle and the subsequent segregation of sister chromatids are based on the self-organized action of microtubule filaments, motor proteins, and other microtubule-associated proteins, which constitute the fundamental force-generating elements in the system. Many of the components in the spindle have been identified, but until recently it remained unclear how their collective behaviors resulted in such a robust bipolar structure. Here, we review the current understanding of the physics of the metaphase spindle that is only now starting to emerge.

  6. Actin depolymerization enhances adipogenic differentiation in human stromal stem cells.

    Science.gov (United States)

    Chen, Li; Hu, Huimin; Qiu, Weimin; Shi, Kaikai; Kassem, Moustapha

    2018-05-01

    Human stromal stem cells (hMSCs) differentiate into adipocytes that play a role in skeletal tissue homeostasis and whole body energy metabolism. During adipocyte differentiation, hMSCs exhibit significant changes in cell morphology suggesting changes in cytoskeletal organization. Here, we examined the effect of direct modulation of actin microfilament dynamics on adipocyte differentiation. Stabilizing actin filaments in hMSCs by siRNA-mediated knock down of the two main actin depolymerizing factors (ADFs): Cofilin 1 (CFL1) and Destrin (DSTN) or treating the cells by Phalloidin reduced adipocyte differentiation as evidenced by decreased number of mature adipocytes and decreased adipocyte specific gene expression (ADIPOQ, LPL, PPARG, FABP4). In contrast, disruption of actin cytoskeleton by Cytochalasin D enhanced adipocyte differentiation. Follow up studies revealed that the effects of CFL1 on adipocyte differentiation depended on the activity of LIM domain kinase 1 (LIMK1) which is the major upstream kinase of CFL1. Inhibiting LIMK by its specific chemical inhibitor LIMKi inhibited the phosphorylation of CFL1 and actin polymerization, and enhanced the adipocyte differentiation. Moreover, treating hMSCs by Cytochalasin D inhibited ERK and Smad2 signaling and this was associated with enhanced adipocyte differentiation. On the other hand, Phalloidin enhanced ERK and Smad2 signaling, but inhibited adipocyte differentiation which was rescued by ERK specific chemical inhibitor U0126. Our data provide a link between restructuring of hMSCs cytoskeleton and hMSCs lineage commitment and differentiation. Copyright © 2018 Elsevier B.V. All rights reserved.

  7. Identification of transcript regulatory patterns in cell differentiation.

    Science.gov (United States)

    Gusnanto, Arief; Gosling, John Paul; Pope, Christopher

    2017-10-15

    Studying transcript regulatory patterns in cell differentiation is critical in understanding its complex nature of the formation and function of different cell types. This is done usually by measuring gene expression at different stages of the cell differentiation. However, if the gene expression data available are only from the mature cells, we have some challenges in identifying transcript regulatory patterns that govern the cell differentiation. We propose to exploit the information of the lineage of cell differentiation in terms of correlation structure between cell types. We assume that two different cell types that are close in the lineage will exhibit many common genes that are co-expressed relative to those that are far in the lineage. Current analysis methods tend to ignore this correlation by testing for differential expression assuming some sort of independence between cell types. We employ a Bayesian approach to estimate the posterior distribution of the mean of expression in each cell type, by taking into account the cell formation path in the lineage. This enables us to infer genes that are specific in each cell type, indicating the genes are involved in directing the cell differentiation to that particular cell type. We illustrate the method using gene expression data from a study of haematopoiesis. R codes to perform the analysis are available in http://www1.maths.leeds.ac.uk/∼arief/R/CellDiff/. a.gusnanto@leeds.ac.uk. Supplementary data are available at Bioinformatics online. © The Author (2017). Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com

  8. Cell culture plastics with immobilized interleukin-4 for monocyte differentiation

    DEFF Research Database (Denmark)

    Hansen, Morten; Hjortø, Gertrud Malene; Met, Özcan

    2011-01-01

    Standard cell culture plastic was surface modified by passive adsorption or covalent attachment of interleukin (IL)-4 and investigated for its ability to induce differentiation of human monocytes into mature dendritic cells, a process dose-dependently regulated by IL-4. Covalent attachment of IL-4...... in water instead of phosphate-buffered saline. Passively adsorbed IL-4 was observed to induce differentiation to dendritic cells, but analysis of cell culture supernatants revealed that leakage of IL-4 into solution could account for the differentiation observed. Covalent attachment resulted in bound IL-4...... at similar concentrations to the passive adsorption process, as measured by enzyme-linked immunosorbent assays, and the bound IL-4 did not leak into solution to any measurable extent during cell culture. However, covalently bound IL-4 was incapable of inducing monocyte differentiation. This may be caused...

  9. Cortical dendritic activity correlates with spindle-rich oscillations during sleep in rodents.

    Science.gov (United States)

    Seibt, Julie; Richard, Clément J; Sigl-Glöckner, Johanna; Takahashi, Naoya; Kaplan, David I; Doron, Guy; de Limoges, Denis; Bocklisch, Christina; Larkum, Matthew E

    2017-09-25

    How sleep influences brain plasticity is not known. In particular, why certain electroencephalographic (EEG) rhythms are linked to memory consolidation is poorly understood. Calcium activity in dendrites is known to be necessary for structural plasticity changes, but this has never been carefully examined during sleep. Here, we report that calcium activity in populations of neocortical dendrites is increased and synchronised during oscillations in the spindle range in naturally sleeping rodents. Remarkably, the same relationship is not found in cell bodies of the same neurons and throughout the cortical column. Spindles during sleep have been suggested to be important for brain development and plasticity. Our results provide evidence for a physiological link of spindles in the cortex specific to dendrites, the main site of synaptic plasticity.Different stages of sleep, marked by particular electroencephalographic (EEG) signatures, have been linked to memory consolidation, but underlying mechanisms are poorly understood. Here, the authors show that dendritic calcium synchronisation correlates with spindle-rich sleep phases.

  10. Lactobacilli Differentially Activate Natural Killer Cells

    DEFF Research Database (Denmark)

    Fink, Lisbeth Nielsen; Christensen, Hanne Risager; Frøkiær, Hanne

    bacteria on regulatory functions of NK-cells. Here, we have investigated how human gut flora-derived non-pathogenic lactobacilli affect NK cells in vitro, by measuring proliferation and IFN-gamma production of human peripheral blood NK cells upon bacterial stimulation. CD3-CD56+ NK cells were isolated from...... having engulfed bacteria, stimulated the growth of the NK cells. In contrast, a Lactobacillus paracasei strain caused the NK cells to proliferate only in the presence of monocytes. These results demonstrate that various lactobacilli have the capacity to activate NK cells in vitro, in a monocyte dependent...

  11. Actin depolymerization enhances adipogenic differentiation in human stromal stem cells

    DEFF Research Database (Denmark)

    Chen, Li; Hu, Huimin; Qiu, Weimin

    2018-01-01

    Human stromal stem cells (hMSCs) differentiate into adipocytes that play a role in skeletal tissue homeostasis and whole body energy metabolism. During adipocyte differentiation, hMSCs exhibit significant changes in cell morphology suggesting changes in cytoskeletal organization. Here, we examined...... the effect of direct modulation of actin microfilament dynamics on adipocyte differentiation. Stabilizing actin filaments in hMSCs by siRNA-mediated knock down of the two main actin depolymerizing factors (ADFs): Cofilin 1 (CFL1) and Destrin (DSTN) or treating the cells by Phalloidin reduced adipocyte...

  12. Cell culture plastics with immobilized interleukin-4 for monocyte differentiation

    DEFF Research Database (Denmark)

    Hansen, Morten; Hjortø, Gertrud Malene; Met, Ozcan

    2011-01-01

    in water instead of phosphate-buffered saline. Passively adsorbed IL-4 was observed to induce differentiation to dendritic cells, but analysis of cell culture supernatants revealed that leakage of IL-4 into solution could account for the differentiation observed. Covalent attachment resulted in bound IL-4...... at similar concentrations to the passive adsorption process, as measured by enzyme-linked immunosorbent assays, and the bound IL-4 did not leak into solution to any measurable extent during cell culture. However, covalently bound IL-4 was incapable of inducing monocyte differentiation. This may be caused...

  13. Differential TCR signals for T helper cell programming.

    Science.gov (United States)

    Morel, Penelope A

    2018-05-02

    Upon encounter with their cognate antigen naïve CD4 T cells become activated and are induced to differentiate into several possible T helper (Th) cell subsets. This differentiation depends on a number of factors including antigen presenting cells, cytokines and costimulatory molecules. The strength of the T cell receptor (TCR) signal, related to the affinity of TCR for antigen and antigen dose, has emerged as a dominant factor in determining Th cell fate. Recent studies have revealed that TCR signals of high or low strength do not simply induce quantitatively different signals in the T cells, but rather qualitatively distinct pathways can be induced based on TCR signal strength. This review examines the recent literature in this area and highlights important new developments in our understanding of Th cell differentiation and TCR signal strength. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  14. Conceptual Challenges of the Systemic Approach in Understanding Cell Differentiation.

    Science.gov (United States)

    Paldi, Andras

    2018-01-01

    The cells of a multicellular organism are derived from a single zygote and genetically identical. Yet, they are phenotypically very different. This difference is the result of a process commonly called cell differentiation. How the phenotypic diversity emerges during ontogenesis or regeneration is a central and intensely studied but still unresolved issue in biology. Cell biology is facing conceptual challenges that are frequently confused with methodological difficulties. How to define a cell type? What stability or change means in the context of cell differentiation and how to deal with the ubiquitous molecular variations seen in the living cells? What are the driving forces of the change? We propose to reframe the problem of cell differentiation in a systemic way by incorporating different theoretical approaches. The new conceptual framework is able to capture the insights made at different levels of cellular organization and considered previously as contradictory. It also provides a formal strategy for further experimental studies.

  15. Alpha-adrenergic blocker mediated osteoblastic stem cell differentiation

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Yoon Jung [Craniomaxillofacial Reconstructive Sciences Major, College of Dentistry, Seoul National University, Seoul 110-749 (Korea, Republic of); Lee, Jue Yeon [Craniomaxillofacial Reconstructive Sciences Major, College of Dentistry, Seoul National University, Seoul 110-749 (Korea, Republic of); Research Center, Nano Intelligent Biomedical Engineering Corporation (NIBEC), Seoul (Korea, Republic of); Lee, Seung Jin [Department of Industrial Pharmacy, College of Pharmacy, Ewha Womans University, Seoul (Korea, Republic of); Research Center, Nano Intelligent Biomedical Engineering Corporation (NIBEC), Seoul (Korea, Republic of); Chung, Chong-Pyoung [Department of Periodontology, School of Dentistry, Seoul National University, Seoul (Korea, Republic of); Research Center, Nano Intelligent Biomedical Engineering Corporation (NIBEC), Seoul (Korea, Republic of); Park, Yoon Jeong, E-mail: parkyj@snu.ac.kr [Craniomaxillofacial Reconstructive Sciences Major, College of Dentistry, Seoul National University, Seoul 110-749 (Korea, Republic of); Research Center, Nano Intelligent Biomedical Engineering Corporation (NIBEC), Seoul (Korea, Republic of)

    2011-12-16

    Highlights: Black-Right-Pointing-Pointer Doxazocin directly up-regulated bone metabolism at a low dose. Black-Right-Pointing-Pointer Doxazocin induced osteoblastic stem cell differentiation without affecting cell proliferation. Black-Right-Pointing-Pointer This osteogenic stem cell differentiation is mediated by ERK-signal dependent pathway. -- Abstract: Recent researches have indicated a role for antihypertensive drugs including alpha- or beta-blockers in the prevention of bone loss. Some epidemiological studies reported the protective effects of those agents on fracture risk. However, there is limited information on the association with those agents especially at the mechanism of action. In the present study, we investigated the effects of doxazosin, an alpha-blocker that is clinically used for the treatment of benign prostatic hyperplasia (BPH) along with antihypertensive medication, on the osteogenic stem cell differentiation. We found that doxazosin increased osteogenic differentiation of human mesenchymal stem cells, detected by Alizarin red S staining and calcein. Doxazosin not only induced expression of alkaline phosphatase, type I collagen, osteopontin, and osteocalcin, it also resulted in increased phosphorylation of extracellular signal-regulated kinase (ERK1/2), a MAP kinase involved in osteoblastic differentiation. Treatment with U0126, a MAP kinase inhibitor, significantly blocked doxazosin-induced osteoblastic differentiation. Unrelated to activation of osteogenic differentiation by doxazosin, we found that there were no significant changes in adipogenic differentiation or in the expression of adipose-specific genes, including peroxisome proliferator-activated receptor {gamma}, aP2, or LPL. In this report, we suggest that doxazosin has the ability to increase osteogenic cell differentiation via ERK1/2 activation in osteogenic differentiation of adult stem cells, which supports the protective effects of antihypertensive drug on fracture risk and

  16. Alpha-adrenergic blocker mediated osteoblastic stem cell differentiation

    International Nuclear Information System (INIS)

    Choi, Yoon Jung; Lee, Jue Yeon; Lee, Seung Jin; Chung, Chong-Pyoung; Park, Yoon Jeong

    2011-01-01

    Highlights: ► Doxazocin directly up-regulated bone metabolism at a low dose. ► Doxazocin induced osteoblastic stem cell differentiation without affecting cell proliferation. ► This osteogenic stem cell differentiation is mediated by ERK-signal dependent pathway. -- Abstract: Recent researches have indicated a role for antihypertensive drugs including alpha- or beta-blockers in the prevention of bone loss. Some epidemiological studies reported the protective effects of those agents on fracture risk. However, there is limited information on the association with those agents especially at the mechanism of action. In the present study, we investigated the effects of doxazosin, an alpha-blocker that is clinically used for the treatment of benign prostatic hyperplasia (BPH) along with antihypertensive medication, on the osteogenic stem cell differentiation. We found that doxazosin increased osteogenic differentiation of human mesenchymal stem cells, detected by Alizarin red S staining and calcein. Doxazosin not only induced expression of alkaline phosphatase, type I collagen, osteopontin, and osteocalcin, it also resulted in increased phosphorylation of extracellular signal-regulated kinase (ERK1/2), a MAP kinase involved in osteoblastic differentiation. Treatment with U0126, a MAP kinase inhibitor, significantly blocked doxazosin-induced osteoblastic differentiation. Unrelated to activation of osteogenic differentiation by doxazosin, we found that there were no significant changes in adipogenic differentiation or in the expression of adipose-specific genes, including peroxisome proliferator-activated receptor γ, aP2, or LPL. In this report, we suggest that doxazosin has the ability to increase osteogenic cell differentiation via ERK1/2 activation in osteogenic differentiation of adult stem cells, which supports the protective effects of antihypertensive drug on fracture risk and according to our data doxazosin might be useful for application in the field of bone

  17. Division of Labor in Biofilms: the Ecology of Cell Differentiation.

    Science.gov (United States)

    van Gestel, Jordi; Vlamakis, Hera; Kolter, Roberto

    2015-04-01

    The dense aggregation of cells on a surface, as seen in biofilms, inevitably results in both environmental and cellular heterogeneity. For example, nutrient gradients can trigger cells to differentiate into various phenotypic states. Not only do cells adapt physiologically to the local environmental conditions, but they also differentiate into cell types that interact with each other. This allows for task differentiation and, hence, the division of labor. In this article, we focus on cell differentiation and the division of labor in three bacterial species: Myxococcus xanthus, Bacillus subtilis, and Pseudomonas aeruginosa. During biofilm formation each of these species differentiates into distinct cell types, in some cases leading to cooperative interactions. The division of labor and the cooperative interactions between cell types are assumed to yield an emergent ecological benefit. Yet in most cases the ecological benefits have yet to be elucidated. A notable exception is M. xanthus, in which cell differentiation within fruiting bodies facilitates the dispersal of spores. We argue that the ecological benefits of the division of labor might best be understood when we consider the dynamic nature of both biofilm formation and degradation.

  18. Molecular biological features of male germ cell differentiation

    Science.gov (United States)

    HIROSE, MIKA; TOKUHIRO, KEIZO; TAINAKA, HITOSHI; MIYAGAWA, YASUSHI; TSUJIMURA, AKIRA; OKUYAMA, AKIHIKO; NISHIMUNE, YOSHITAKE

    2007-01-01

    Somatic cell differentiation is required throughout the life of a multicellular organism to maintain homeostasis. In contrast, germ cells have only one specific function; to preserve the species by conveying the parental genes to the next generation. Recent studies of the development and molecular biology of the male germ cell have identified many genes, or isoforms, that are specifically expressed in the male germ cell. In the present review, we consider the unique features of male germ cell differentiation. (Reprod Med Biol 2007; 6: 1–9) PMID:29699260

  19. Semaphorin-Plexin Signaling Controls Mitotic Spindle Orientation during Epithelial Morphogenesis and Repair

    DEFF Research Database (Denmark)

    Xia, Jingjing; Swiercz, Jakub M.; Bañón-Rodríguez, Inmaculada

    2015-01-01

    Morphogenesis, homeostasis, and regeneration of epithelial tissues rely on the accurate orientation of cell divisions, which is specified by the mitotic spindle axis. To remain in the epithelial plane, symmetrically dividing epithelial cells align their mitotic spindle axis with the plane. Here, we...... show that this alignment depends on epithelial cell-cell communication via semaphorin-plexin signaling. During kidney morphogenesis and repair, renal tubular epithelial cells lacking the transmembrane receptor Plexin-B2 or its semaphorin ligands fail to correctly orient the mitotic spindle, leading...... to severe defects in epithelial architecture and function. Analyses of a series of transgenic and knockout mice indicate that Plexin-B2 controls the cell division axis by signaling through its GTPase-activating protein (GAP) domain and Cdc42. Our data uncover semaphorin-plexin signaling as a central...

  20. Differentiation of Dental Pulp Stem Cells into Neuron-Like Cells in Serum-Free Medium

    Directory of Open Access Journals (Sweden)

    Shahrul Hisham Zainal Ariffin

    2013-01-01

    Full Text Available Dental pulp tissue contains dental pulp stem cells (DPSCs. Dental pulp cells (also known as dental pulp-derived mesenchymal stem cells are capable of differentiating into multilineage cells including neuron-like cells. The aim of this study was to examine the capability of DPSCs to differentiate into neuron-like cells without using any reagents or growth factors. DPSCs were isolated from teeth extracted from 6- to 8-week-old mice and maintained in complete medium. The cells from the fourth passage were induced to differentiate by culturing in medium without serum or growth factors. RT-PCR molecular analysis showed characteristics of Cd146+, Cd166+, and Cd31− in DPSCs, indicating that these cells are mesenchymal stem cells rather than hematopoietic stem cells. After 5 days of neuronal differentiation, the cells showed neuron-like morphological changes and expressed MAP2 protein. The activation of Nestin was observed at low level prior to differentiation and increased after 5 days of culture in differentiation medium, whereas Tub3 was activated only after 5 days of neuronal differentiation. The proliferation of the differentiated cells decreased in comparison to that of the control cells. Dental pulp stem cells are induced to differentiate into neuron-like cells when cultured in serum- and growth factor-free medium.

  1. Actin depolymerization enhances adipogenic differentiation in human stromal stem cells

    DEFF Research Database (Denmark)

    Chen, Li; Hu, Huimin; Qiu, Weimin

    2018-01-01

    Human stromal stem cells (hMSCs) differentiate into adipocytes that play a role in skeletal tissue homeostasis and whole body energy metabolism. During adipocyte differentiation, hMSCs exhibit significant changes in cell morphology suggesting changes in cytoskeletal organization. Here, we examined...... differentiation as evidenced by decreased number of mature adipocytes and decreased adipocyte specific gene expression (ADIPOQ, LPL, PPARG, FABP4). In contrast, disruption of actin cytoskeleton by Cytochalasin D enhanced adipocyte differentiation. Follow up studies revealed that the effects of CFL1 on adipocyte...... differentiation depended on the activity of LIM domain kinase 1 (LIMK1) which is the major upstream kinase of CFL1. Inhibiting LIMK by its specific chemical inhibitor LIMKi inhibited the phosphorylation of CFL1 and actin polymerization, and enhanced the adipocyte differentiation. Moreover, treating h...

  2. Kinesin-8 effects on mitotic microtubule dynamics contribute to spindle function in fission yeast

    Science.gov (United States)

    Gergely, Zachary R.; Crapo, Ammon; Hough, Loren E.; McIntosh, J. Richard; Betterton, Meredith D.

    2016-01-01

    Kinesin-8 motor proteins destabilize microtubules. Their absence during cell division is associated with disorganized mitotic chromosome movements and chromosome loss. Despite recent work studying effects of kinesin-8s on microtubule dynamics, it remains unclear whether the kinesin-8 mitotic phenotypes are consequences of their effect on microtubule dynamics, their well-established motor activity, or additional, unknown functions. To better understand the role of kinesin-8 proteins in mitosis, we studied the effects of deletion of the fission yeast kinesin-8 proteins Klp5 and Klp6 on chromosome movements and spindle length dynamics. Aberrant microtubule-driven kinetochore pushing movements and tripolar mitotic spindles occurred in cells lacking Klp5 but not Klp6. Kinesin-8–deletion strains showed large fluctuations in metaphase spindle length, suggesting a disruption of spindle length stabilization. Comparison of our results from light microscopy with a mathematical model suggests that kinesin-8–induced effects on microtubule dynamics, kinetochore attachment stability, and sliding force in the spindle can explain the aberrant chromosome movements and spindle length fluctuations seen. PMID:27146110

  3. Mirna biogenesis pathway is differentially regulated during adipose derived stromal/stem cell differentiation.

    Science.gov (United States)

    Martin, E C; Qureshi, A T; Llamas, C B; Burow, M E; King, A G; Lee, O C; Dasa, V; Freitas, M A; Forsberg, J A; Elster, E A; Davis, T A; Gimble, J M

    2018-02-07

    Stromal/stem cell differentiation is controlled by a vast array of regulatory mechanisms. Included within these are methods of mRNA gene regulation that occur at the level of epigenetic, transcriptional, and/or posttranscriptional modifications. Current studies that evaluate the posttranscriptional regulation of mRNA demonstrate microRNAs (miRNAs) as key mediators of stem cell differentiation through the inhibition of mRNA translation. miRNA expression is enhanced during both adipogenic and osteogenic differentiation; however, the mechanism by which miRNA expression is altered during stem cell differentiation is less understood. Here we demonstrate for the first time that adipose-derived stromal/stem cells (ASCs) induced to an adipogenic or osteogenic lineage have differences in strand preference (-3p and -5p) for miRNAs originating from the same primary transcript. Furthermore, evaluation of miRNA expression in ASCs demonstrates alterations in both miRNA strand preference and 5'seed site heterogeneity. Additionally, we show that during stem cell differentiation there are alterations in expression of genes associated with the miRNA biogenesis pathway. Quantitative RT-PCR demonstrated changes in the Argonautes (AGO1-4), Drosha, and Dicer at intervals of ASC adipogenic and osteogenic differentiation compared to untreated ASCs. Specifically, we demonstrated altered expression of the AGOs occurring during both adipogenesis and osteogenesis, with osteogenesis increasing AGO1-4 expression and adipogenesis decreasing AGO1 gene and protein expression. These data demonstrate changes to components of the miRNA biogenesis pathway during stromal/stem cell differentiation. Identifying regulatory mechanisms for miRNA processing during ASC differentiation may lead to novel mechanisms for the manipulation of lineage differentiation of the ASC through the global regulation of miRNA as opposed to singular regulatory mechanisms.

  4. Differentiation ability of rat postnatal dental pulp cells in vitro.

    NARCIS (Netherlands)

    Zhang, W.; Walboomers, X.F.; Wolke, J.G.C.; Bian, Z.; Fan, M.W.; Jansen, J.A.

    2005-01-01

    The current rapid progression in stem cell research has enhanced our knowledge of dental tissue regeneration. In this study, rat dental pulp cells were isolated and their differentiation ability was evaluated. First, dental pulp cells were obtained from maxillary incisors of male Wistar rats.

  5. Division of labor in biofilms : The ecology of cell differentiation

    NARCIS (Netherlands)

    van Gestel, Jordi; Vlamakis, Hera; Kolter, Roberto

    The dense aggregation of cells on a surface, as seen in biofilms, inevitably results in both environmental and cellular heterogeneity. For example, nutrient gradients can trigger cells to differentiate into various phenotypic states. Not only do cells adapt physiologically to the local environmental

  6. Pathways in pluripotency and differentiation of embryonic cells

    NARCIS (Netherlands)

    du Puy, L.

    2010-01-01

    Pluripotency - the potential to differentiate into derivatives of the three embryonic germ layers endoderm, ectoderm and mesoderm - is the main characteristic of embryonic stem (ES) cells. ES cells are derived from the inner cell mass (ICM) of a pre-implantation blastocyst and can self-renew

  7. Changes in total and differential white cell counts, total lymphocyte ...

    African Journals Online (AJOL)

    Background: Published reports on the possible changes in the various immune cell populations, especially the total lymphocyte and CD4 cell counts, during the menstrual cycle in Nigerian female subjects are relatively scarce. Aim: To determine possible changes in the total and differential white blood cell [WBC] counts, ...

  8. Pituitary cell differentiation from stem cells and other cells: toward restorative therapy for hypopituitarism?

    Science.gov (United States)

    Willems, Christophe; Vankelecom, Hugo

    2014-01-01

    The pituitary gland, key regulator of our endocrine system, produces multiple hormones that steer essential physiological processes. Hence, deficient pituitary function (hypopituitarism) leads to severe disorders. Hypopituitarism can be caused by defective embryonic development, or by damage through tumor growth/resection and traumatic brain injury. Lifelong hormone replacement is needed but associated with significant side effects. It would be more desirable to restore pituitary tissue and function. Recently, we showed that the adult (mouse) pituitary holds regenerative capacity in which local stem cells are involved. Repair of deficient pituitary may therefore be achieved by activating these resident stem cells. Alternatively, pituitary dysfunction may be mended by cell (replacement) therapy. The hormonal cells to be transplanted could be obtained by (trans-)differentiating various kinds of stem cells or other cells. Here, we summarize the studies on pituitary cell regeneration and on (trans-)differentiation toward hormonal cells, and speculate on restorative therapies for pituitary deficiency.

  9. Differential radiosensitivity among B cell subpopulations

    International Nuclear Information System (INIS)

    Riggs, J.E.

    1988-01-01

    The selective radiosensitivity of sIgM >> sIgD marginal zone B cells is associated with the selective loss of B cell function. The simultaneous restoration of impaired function and recovery of these cells with time supports this premise. B cell recovery, delayed one week after irradiation, is in progress at two weeks, and virtually complete by three weeks. XID mice reveal similar recovery kinetics although there are fewer recovering cells and these bear reduced levels of Ia. This observation represents additional evidence that xid B cells are distinct from those of normal mice. The simultaneous loss, and concurrent recovery, of sIgM >> sIgD B cells and TI-2 responsiveness in irradiated mice suggests the existence of a unique B cell subpopulation possessing both phenotypes. Additional support for this hypothesis is provided by demonstrating that splenocytes, depleted of IgD + cells adoptively reconstitute this response in XID mice. The peritoneal B cell pool, which, compared to the spleen, consist of increased numbers of sIgM >> sIgD B cells, is shown to be a source of radiosensitive B cells that are TI-2 responsive. These observations represent additional evidence for an association between sIgM >> sIgD B cells and TI-2 responsiveness

  10. Chemical strategies for pancreatic β cell differentiation, reprogramming, and regeneration.

    Science.gov (United States)

    Ma, Xiaojie; Zhu, Saiyong

    2017-04-01

    Generation of unlimited functional pancreatic β cells is critical for the study of pancreatic biology and treatment of diabetes mellitus. Recent advances have suggested several promising directions, including directed differentiation of pancreatic β cells from pluripotent stem cells, reprogramming of pancreatic β cells from other types of somatic cells, and stimulated proliferation and enhanced functions of existing pancreatic β cells. Small molecules are useful in generating unlimited numbers of functional pancreatic cells in vitro and could be further developed as drugs to stimulate endogenous pancreatic regeneration. Here, we provide an updated summary of recent major achievements in pancreatic β cell differentiation, reprogramming, proliferation, and function. These studies will eventually lead to significant advances in the field of pancreatic biology and regeneration. © The Author 2017. Published by Oxford University Press on behalf of the Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  11. Analytical modeling for thermal errors of motorized spindle unit

    OpenAIRE

    Liu, Teng; Gao, Weiguo; Zhang, Dawei; Zhang, Yifan; Chang, Wenfen; Liang, Cunman; Tian, Yanling

    2017-01-01

    Modeling method investigation about spindle thermal errors is significant for spindle thermal optimization in design phase. To accurately analyze the thermal errors of motorized spindle unit, this paper assumes approximately that 1) spindle linear thermal error on axial direction is ascribed to shaft thermal elongation for its heat transfer from bearings, and 2) spindle linear thermal errors on radial directions and angular thermal errors are attributed to thermal variations of bearing relati...

  12. Cell differentiation and matrix organization in engineered teeth.

    Science.gov (United States)

    Nait Lechguer, A; Couble, M L; Labert, N; Kuchler-Bopp, S; Keller, L; Magloire, H; Bleicher, F; Lesot, H

    2011-05-01

    Embryonic dental cells were used to check a series of criteria to be achieved for tooth engineering. Implantation of cultured cell-cell re-associations led to crown morphogenesis, epithelial histogenesis, organ vascularization, and root and periodontium development. The present work aimed to investigate the organization of predentin/dentin, enamel, and cementum which formed and mineralized after implantation. These implants were processed for histology, transmission electron microscopy, x-ray microanalysis, and electron diffraction. After two weeks of implantation, the re-associations showed gradients of differentiating odontoblasts. There were ciliated, polarized, and extended cell processes in predentin/dentin. Ameloblasts became functional. Enamel crystals showed a typical oriented arrangement in the inner and outer enamel. In the developing root, odontoblasts differentiated, cementogenesis occurred, and periodontal ligament fibroblasts interacted with the root surface and newly formed bone. The implantation of cultured dental cell re-associations allows for reproduction of complete functional differentiation at the cell, matrix, and mineral levels.

  13. Differentiation of Spermatogonia Stem Cells into Functional Mature Neurons Characterized with Differential Gene Expression.

    Science.gov (United States)

    Bojnordi, Maryam Nazm; Azizi, Hossein; Skutella, Thomas; Movahedin, Mansoureh; Pourabdolhossein, Fereshteh; Shojaei, Amir; Hamidabadi, Hatef Ghasemi

    2017-09-01

    Transplantation of embryonic stem cells (ESCs) is a promising therapeutic approach for the treatment of neurodegenerative diseases. However, ESCs are not usable clinically due to immunological and ethical limitations. The identification of an alternative safe cell source opens novel options via autologous transplantation in neuro-regeneration circumventing these problems. Here, we examined the neurogenic capacity of embryonic stem-like cells (ES-like cells) derived from the testis using neural growth factor inducers and utilized them to generate functional mature neurons. The neuronal differentiation of ES-like cells is induced in three stages. Stage 1 is related to embryoid body (EB) formation. To induce neuroprogenitor cells, EBs were cultured in the presence of retinoic acid, N 2 supplement and fibroblast growth factor followed by culturing in a neurobasal medium containing B 27 , N 2 supplements for additional 10 days, to allow the maturation and development of neuronal progenitor cells. The neurogenic differentiation was confirmed by immunostaining for markers of mature neurons. The differentiated neurons were positive for Tuj1 and Tau1. Real-time PCR dates indicated the expression of Nestin and Neuro D (neuroprogenitor markers) in induced cells at the second stage of the differentiation protocol. The differentiated mature neurons exhibited the specific neuron markers Map2 and β-tubulin. The functional maturity of neurons was confirmed by an electrophysiological analysis of passive and active neural membrane properties. These findings indicated a differentiation capacity of ES-like cells derived from the testis to functionally mature neurons, which proposes them as a novel cell source for neuroregenerative medicine.

  14. Actin depolymerization enhances adipogenic differentiation in human stromal stem cells

    Directory of Open Access Journals (Sweden)

    Li Chen

    2018-05-01

    Full Text Available Human stromal stem cells (hMSCs differentiate into adipocytes that play a role in skeletal tissue homeostasis and whole body energy metabolism. During adipocyte differentiation, hMSCs exhibit significant changes in cell morphology suggesting changes in cytoskeletal organization. Here, we examined the effect of direct modulation of actin microfilament dynamics on adipocyte differentiation. Stabilizing actin filaments in hMSCs by siRNA-mediated knock down of the two main actin depolymerizing factors (ADFs: Cofilin 1 (CFL1 and Destrin (DSTN or treating the cells by Phalloidin reduced adipocyte differentiation as evidenced by decreased number of mature adipocytes and decreased adipocyte specific gene expression (ADIPOQ, LPL, PPARG, FABP4. In contrast, disruption of actin cytoskeleton by Cytochalasin D enhanced adipocyte differentiation. Follow up studies revealed that the effects of CFL1 on adipocyte differentiation depended on the activity of LIM domain kinase 1 (LIMK1 which is the major upstream kinase of CFL1. Inhibiting LIMK by its specific chemical inhibitor LIMKi inhibited the phosphorylation of CFL1 and actin polymerization, and enhanced the adipocyte differentiation. Moreover, treating hMSCs by Cytochalasin D inhibited ERK and Smad2 signaling and this was associated with enhanced adipocyte differentiation. On the other hand, Phalloidin enhanced ERK and Smad2 signaling, but inhibited adipocyte differentiation which was rescued by ERK specific chemical inhibitor U0126. Our data provide a link between restructuring of hMSCs cytoskeleton and hMSCs lineage commitment and differentiation. Keywords: Actin cytoskeleton, Actin depolymerizing factors, Adipocyte differentiation, Human stromal stem cells

  15. Current perspectives in Set7 mediated stem cell differentiation

    Directory of Open Access Journals (Sweden)

    Nazanin Karimnia

    2016-12-01

    Full Text Available Set7 is a key regulatory enzyme involved in the methylation of lysine residues of histone and non-histone proteins. This lysine methyltransferase is induced during stem cell differentiation and regulates lineage specific gene transcription and cell fate. In this article we discuss recent experimental evidence identifying regulatory targets under the control of Set7 as well as emerging evidence of regulation in stem cell differentiation. Furthermore, we discuss the function of non-coding RNAs regulated by Set7 implicated in cell plasticity.

  16. In vitro differentiation of primordial germ cells and oocyte-like cells from stem cells.

    Science.gov (United States)

    Costa, José J N; Souza, Glaucinete B; Soares, Maria A A; Ribeiro, Regislane P; van den Hurk, Robert; Silva, José R V

    2018-02-01

    Infertility is the result of failure due to an organic disorder of the reproductive organs, especially their gametes. Recently, much progress has been made on generating germ cells, including oocytes, from various types of stem cells. This review focuses on advances in female germ cell differentiation from different kinds of stem cells, with emphasis on embryonic stem cells, adult stem cells, and induced pluripotent stem cells. The advantages and disadvantages of the derivation of female germ cells from several types of stem cells are also highlighted, as well as the ability of stem cells to generate mature and functional female gametes. This review shows that stem cell therapies have opened new frontiers in medicine, especially in the reproductive area, with the possibility of regenerating fertility.

  17. Redox environment in stem and differentiated cells: A quantitative approach

    Directory of Open Access Journals (Sweden)

    O.G. Lyublinskaya

    2017-08-01

    Full Text Available Stem cells are believed to maintain a specific intracellular redox status through a combination of enhanced removal capacity and limited production of ROS. In the present study, we challenge this assumption by developing a quantitative approach for the analysis of the pro- and antioxidant ability of human embryonic stem cells in comparison with their differentiated descendants, as well as adult stem and non-stem cells. Our measurements showed that embryonic stem cells are characterized by low ROS level, low rate of extracellular hydrogen peroxide removal and low threshold for peroxide-induced cytotoxicity. However, biochemical normalization of these parameters to cell volume/protein leads to matching of normalized values in stem and differentiated cells and shows that tested in the present study cells (human embryonic stem cells and their fibroblast-like progenies, adult mesenchymal stem cells, lymphocytes, HeLa maintain similar intracellular redox status. Based on these observations, we propose to use ROS concentration averaged over the cell volume instead of ROS level as a measure of intracellular redox balance. We show that attempts to use ROS level for comparative analysis of redox status of morphologically different cells could lead to false conclusions. Methods for the assessment of ROS concentration based on flow cytometry analysis with the use of H2DCFDA dye and HyPer, genetically encoded probe for hydrogen peroxide, are discussed. Keywords: Embryonic stem cells, Differentiated cells, ROS, Redox status, H2DCFDA, HyPer, Flow cytometry, Quantitative redox biology

  18. Engineering kidney cells: reprogramming and directed differentiation to renal tissues.

    Science.gov (United States)

    Kaminski, Michael M; Tosic, Jelena; Pichler, Roman; Arnold, Sebastian J; Lienkamp, Soeren S

    2017-07-01

    Growing knowledge of how cell identity is determined at the molecular level has enabled the generation of diverse tissue types, including renal cells from pluripotent or somatic cells. Recently, several in vitro protocols involving either directed differentiation or transcription-factor-based reprogramming to kidney cells have been established. Embryonic stem cells or induced pluripotent stem cells can be guided towards a kidney fate by exposing them to combinations of growth factors or small molecules. Here, renal development is recapitulated in vitro resulting in kidney cells or organoids that show striking similarities to mammalian embryonic nephrons. In addition, culture conditions are also defined that allow the expansion of renal progenitor cells in vitro. Another route towards the generation of kidney cells is direct reprogramming. Key transcription factors are used to directly impose renal cell identity on somatic cells, thus circumventing the pluripotent stage. This complementary approach to stem-cell-based differentiation has been demonstrated to generate renal tubule cells and nephron progenitors. In-vitro-generated renal cells offer new opportunities for modelling inherited and acquired renal diseases on a patient-specific genetic background. These cells represent a potential source for developing novel models for kidney diseases, drug screening and nephrotoxicity testing and might represent the first steps towards kidney cell replacement therapies. In this review, we summarize current approaches for the generation of renal cells in vitro and discuss the advantages of each approach and their potential applications.

  19. Insulin redirects differentiation from cardiogenic mesoderm and endoderm to neuroectoderm in differentiating human embryonic stem cells.

    NARCIS (Netherlands)

    Freund, C.M.A.H.; Ward-van Oostwaard, D.; Monshouwer-Kloots, J.; van den Brink, S.; van Rooijen, M.A.; Xu, X.; Zweigerdt, R.; Mummery, C.L.; Passier, R.

    2008-01-01

    Human embryonic stem cells (hESC) can proliferate indefinitely while retaining the capacity to form derivatives of all three germ layers. We have reported previously that hESC differentiate into cardiomyocytes when cocultured with a visceral endoderm-like cell line (END-2). Insulin/insulin-like

  20. Cancer stem cell markers in patterning differentiation and in prognosis of oral squamous cell carcinoma.

    Science.gov (United States)

    Mohanta, Simple; Siddappa, Gangotri; Valiyaveedan, Sindhu Govindan; Dodda Thimmasandra Ramanjanappa, Ravindra; Das, Debashish; Pandian, Ramanan; Khora, Samanta Sekhar; Kuriakose, Moni Abraham; Suresh, Amritha

    2017-06-01

    Differentiation is a major histological parameter determining tumor aggressiveness and prognosis of the patient; cancer stem cells with their slow dividing and undifferentiated nature might be one of the factors determining the same. This study aims to correlate cancer stem cell markers (CD44 and CD147) with tumor differentiation and evaluate their subsequent effect on prognosis. Immunohistochemical analysis in treatment naïve oral cancer patients (n = 53) indicated that the expression of CD147 was associated with poorly differentiated squamous cell carcinoma and moderately differentiated squamous cell carcinoma (p squamous cell carcinoma and poorly differentiated squamous cell carcinoma patients were CD44 high /CD147 high as compared to only 10% of patients with well-differentiated squamous cell carcinoma. A three-way analysis indicated that differentiation correlated with recurrence and survival (p oral squamous cell carcinoma cell lines originating from different grades of oral cancer. Flowcytometry-based analysis indicated an increase in CD44 + /CD147 + cells in cell lines of poorly differentiated squamous cell carcinoma (94.35 ± 1.14%, p squamous cell carcinoma origin (93.49 ± 0.47%, p squamous cell carcinoma origin (23.12% ± 0.49%). Expression profiling indicated higher expression of cancer stem cell and epithelial-mesenchymal transition markers in SCC029B (poorly differentiated squamous cell carcinoma originated; p ≤ 0.001), which was further translated into increased spheroid formation, migration, and invasion (p squamous cell carcinoma origin. This study suggests that CD44 and CD147 together improve the prognostic efficacy of tumor differentiation; in vitro results further point out that these markers might be determinant of differentiation characteristics, imparting properties of increased self-renewal, migration, and invasion.

  1. Effect of coumarins on HL-60 cell differentiation.

    Science.gov (United States)

    Kawaii, S; Tomono, Y; Katase, E; Ogawa, K; Yano, M

    2000-01-01

    Twenty-eight coumarins, including 7 furocoumarins, were examined for their activity of induction of terminal differentiation of human promyelocytic leukemia cells (HL-60) by nitro blue tetrazolium (NBT) reducing, nonspecific esterase, specific esterase and phagocytic activities. Esculetin, nordalbergin, 6,7-dihydroxy-4-methylcoumarin and imperatorin had strong activity among the coumarins examined. HL-60 cells treated with these coumarins differentiated into mature monocyte/macrophage. The structure-activity relationship established from the results revealed that 6,7-dihydroxy moiety had an important role in the induction of differentiation of HL-60.

  2. Differential expression of cell adhesion genes

    DEFF Research Database (Denmark)

    Stein, Wilfred D; Litman, Thomas; Fojo, Tito

    2005-01-01

    that compare cells grown in suspension to similar cells grown attached to one another as aggregates have suggested that it is adhesion to the extracellular matrix of the basal membrane that confers resistance to apoptosis and, hence, resistance to cytotoxins. The genes whose expression correlates with poor...... in cell adhesion and the cytoskeleton. If the proteins involved in tethering cells to the extracellular matrix are important in conferring drug resistance, it may be possible to improve chemotherapy by designing drugs that target these proteins....

  3. Spindle formation in the mouse embryo requires Plk4 in the absence of centrioles.

    Science.gov (United States)

    Coelho, Paula A; Bury, Leah; Sharif, Bedra; Riparbelli, Maria G; Fu, Jingyan; Callaini, Giuliano; Glover, David M; Zernicka-Goetz, Magdalena

    2013-12-09

    During the first five rounds of cell division in the mouse embryo, spindles assemble in the absence of centrioles. Spindle formation initiates around chromosomes, but the microtubule nucleating process remains unclear. Here we demonstrate that Plk4, a protein kinase known as a master regulator of centriole formation, is also essential for spindle assembly in the absence of centrioles. Depletion of maternal Plk4 prevents nucleation and growth of microtubules and results in monopolar spindle formation. This leads to cytokinesis failure and, consequently, developmental arrest. We show that Plk4 function depends on its kinase activity and its partner protein, Cep152. Moreover, tethering Cep152 to cellular membranes sequesters Plk4 and is sufficient to trigger spindle assembly from ectopic membranous sites. Thus, the Plk4-Cep152 complex has an unexpected role in promoting microtubule nucleation in the vicinity of chromosomes to mediate bipolar spindle formation in the absence of centrioles. Copyright © 2013 The Authors. Published by Elsevier Inc. All rights reserved.

  4. Clathrin heavy chain 1 is required for spindle assembly and chromosome congression in mouse oocytes.

    Science.gov (United States)

    Zhao, Jie; Wang, Lu; Zhou, Hong-Xia; Liu, Li; Lu, Angeleem; Li, Guang-Peng; Schatten, Heide; Liang, Cheng-Guang

    2013-10-01

    Clathrin heavy chain 1 (CLTC) has been considered a “moonlighting protein” which acts in membrane trafficking during interphase and in stabilizing spindle fibers during mitosis. However, its roles in meiosis, especially in mammalian oocyte maturation, remain unclear. This study investigated CLTC expression and function in spindle formation and chromosome congression during mouse oocyte meiotic maturation. Our results showed that the expression level of CLTC increased after germinal vesicle breakdown (GVBD) and peaked in the M phase. Immunostaining results showed CLTC distribution throughout the cytoplasm in a cell cycle-dependent manner. Appearance and disappearance of CLTC along with β-tubulin (TUBB) could be observed during spindle dynamic changes. To explore the relationship between CLTC and microtubule dynamics, oocytes at metaphase were treated with taxol or nocodazole. CLTC colocalized with TUBB at the enlarged spindle and with cytoplasmic asters after taxol treatment; it disassembled and distributed into the cytoplasm along with TUBB after nocodazole treatment. Disruption of CLTC function using stealth siRNA caused a decreased first polar body extrusion rate and extensive spindle formation and chromosome congression defects. Taken together, these results show that CLTC plays an important role in spindle assembly and chromosome congression through a microtubule correlation mechanism during mouse oocyte maturation.

  5. Influence of Porcine Intervertebral Disc Matrix on Stem Cell Differentiation

    Directory of Open Access Journals (Sweden)

    Hans-Lothar Fuchsbauer

    2011-08-01

    Full Text Available For back disorders, cell therapy is one approach for a real regeneration of a degenerated nucleus pulposus. Human mesenchymal stem cells (hMSC could be differentiated into nucleus pulposus (NP-like cells and used for cell therapy. Therefore it is necessary to find a suitable biocompatible matrix, which supports differentiation. It could be shown that a differentiation of hMSC in a microbial transglutaminase cross-linked gelatin matrix is possible, but resulted in a more chondrocyte-like cell type. The addition of porcine NP extract to the gelatin matrix caused a differentiation closer to the desired NP cell phenotype. This concludes that a hydrogel containing NP extract without any other supplements could be suitable for differentiation of hMSCs into NP cells. The NP extract itself can be cross-linked by transglutaminase to build a hydrogel free of NP atypical substrates. As shown by side-specific biotinylation, the NP extract contains molecules with free glutamine and lysine residues available for the transglutaminase.

  6. Efficient differentiation of human embryonic stem cells to definitive endoderm.

    Science.gov (United States)

    D'Amour, Kevin A; Agulnick, Alan D; Eliazer, Susan; Kelly, Olivia G; Kroon, Evert; Baetge, Emmanuel E

    2005-12-01

    The potential of human embryonic stem (hES) cells to differentiate into cell types of a variety of organs has generated much excitement over the possible use of hES cells in therapeutic applications. Of great interest are organs derived from definitive endoderm, such as the pancreas. We have focused on directing hES cells to the definitive endoderm lineage as this step is a prerequisite for efficient differentiation to mature endoderm derivatives. Differentiation of hES cells in the presence of activin A and low serum produced cultures consisting of up to 80% definitive endoderm cells. This population was further enriched to near homogeneity using the cell-surface receptor CXCR4. The process of definitive endoderm formation in differentiating hES cell cultures includes an apparent epithelial-to-mesenchymal transition and a dynamic gene expression profile that are reminiscent of vertebrate gastrulation. These findings may facilitate the use of hES cells for therapeutic purposes and as in vitro models of development.

  7. Cell Fate and Differentiation of Bone Marrow Mesenchymal Stem Cells

    Directory of Open Access Journals (Sweden)

    Shoichiro Kokabu

    2016-01-01

    Full Text Available Osteoblasts and bone marrow adipocytes originate from bone marrow mesenchymal stem cells (BMMSCs and there appears to be a reciprocal relationship between adipogenesis and osteoblastogenesis. Alterations in the balance between adipogenesis and osteoblastogenesis in BMMSCs wherein adipogenesis is increased relative to osteoblastogenesis are associated with decreased bone quality and quantity. Several proteins have been reported to regulate this reciprocal relationship but the exact nature of the signals regulating the balance between osteoblast and adipocyte formation within the bone marrow space remains to be determined. In this review, we focus on the role of Transducin-Like Enhancer of Split 3 (TLE3, which was recently reported to regulate the balance between osteoblast and adipocyte formation from BMMSCs. We also discuss evidence implicating canonical Wnt signalling, which plays important roles in both adipogenesis and osteoblastogenesis, in regulating TLE3 expression. Currently, there is demand for new effective therapies that target the stimulation of osteoblast differentiation to enhance bone formation. We speculate that reducing TLE3 expression or activity in BMMSCs could be a useful approach towards increasing osteoblast numbers and reducing adipogenesis in the bone marrow environment.

  8. Histone h1 depletion impairs embryonic stem cell differentiation.

    Science.gov (United States)

    Zhang, Yunzhe; Cooke, Marissa; Panjwani, Shiraj; Cao, Kaixiang; Krauth, Beth; Ho, Po-Yi; Medrzycki, Magdalena; Berhe, Dawit T; Pan, Chenyi; McDevitt, Todd C; Fan, Yuhong

    2012-01-01

    Pluripotent embryonic stem cells (ESCs) are known to possess a relatively open chromatin structure; yet, despite efforts to characterize the chromatin signatures of ESCs, the role of chromatin compaction in stem cell fate and function remains elusive. Linker histone H1 is important for higher-order chromatin folding and is essential for mammalian embryogenesis. To investigate the role of H1 and chromatin compaction in stem cell pluripotency and differentiation, we examine the differentiation of embryonic stem cells that are depleted of multiple H1 subtypes. H1c/H1d/H1e triple null ESCs are more resistant to spontaneous differentiation in adherent monolayer culture upon removal of leukemia inhibitory factor. Similarly, the majority of the triple-H1 null embryoid bodies (EBs) lack morphological structures representing the three germ layers and retain gene expression signatures characteristic of undifferentiated ESCs. Furthermore, upon neural differentiation of EBs, triple-H1 null cell cultures are deficient in neurite outgrowth and lack efficient activation of neural markers. Finally, we discover that triple-H1 null embryos and EBs fail to fully repress the expression of the pluripotency genes in comparison with wild-type controls and that H1 depletion impairs DNA methylation and changes of histone marks at promoter regions necessary for efficiently silencing pluripotency gene Oct4 during stem cell differentiation and embryogenesis. In summary, we demonstrate that H1 plays a critical role in pluripotent stem cell differentiation, and our results suggest that H1 and chromatin compaction may mediate pluripotent stem cell differentiation through epigenetic repression of the pluripotency genes.

  9. Proteomic analysis of osteogenic differentiation of dental follicle precursor cells

    DEFF Research Database (Denmark)

    Morsczeck, Christian; Petersen, Jørgen; Völlner, Florian

    2009-01-01

    of differentiation. In the present study we applied 2-DE combined with capillary-LC-MS/MS analysis to profile differentially regulated proteins upon differentiation of dental follicle precursor cells (DFPCs). Out of 115 differentially regulated proteins, glutamine synthetase, lysosomal proteinase cathepsin B....... The bioinformatic analyses suggest that proteins associated with cell cycle progression and protein metabolism were down-regulated and proteins involved in catabolism, cell motility and biological quality were up-regulated. These results display the general physiological state of DFPCs before and after osteogenic...... proteins, plastin 3 T-isoform, beta-actin, superoxide dismutases, and transgelin were found to be highly up-regulated, whereas cofilin-1, pro-alpha 1 collagen, destrin, prolyl 4-hydrolase and dihydrolipoamide dehydrogenase were found to be highly down-regulated. The group of up-regulated proteins...

  10. Cloning mice and ES cells by nuclear transfer from somatic stem cells and fully differentiated cells.

    Science.gov (United States)

    Wang, Zhongde

    2011-01-01

    Cloning animals by nuclear transfer (NT) has been successful in several mammalian species. In addition to cloning live animals (reproductive cloning), this technique has also been used in several species to establish cloned embryonic stem (ntES) cell lines from somatic cells. It is the latter application of this technique that has been heralded as being the potential means to produce isogenic embryonic stem cells from patients for cell therapy (therapeutic cloning). These two types of cloning differ only in the steps after cloned embryos are produced: for reproductive cloning the cloned embryos are transferred to surrogate mothers to allow them to develop to full term and for therapeutic cloning the cloned embryos are used to derive ntES cells. In this chapter, a detailed NT protocol in mouse by using somatic stem cells (neuron and skin stem cells) and fully differentiated somatic cells (cumulus cells and fibroblast cells) as nuclear donors is described.

  11. Chronology of Islet Differentiation Revealed By Temporal Cell Labeling

    Science.gov (United States)

    Miyatsuka, Takeshi; Li, Zhongmei; German, Michael S.

    2009-01-01

    OBJECTIVE Neurogenin 3 plays a pivotal role in pancreatic endocrine differentiation. Whereas mouse models expressing reporters such as eGFP or LacZ under the control of the Neurog3 gene enable us to label cells in the pancreatic endocrine lineage, the long half-life of most reporter proteins makes it difficult to distinguish cells actively expressing neurogenin 3 from differentiated cells that have stopped transcribing the gene. RESEARCH DESIGN AND METHODS In order to separate the transient neurogenin 3 –expressing endocrine progenitor cells from the differentiating endocrine cells, we developed a mouse model (Ngn3-Timer) in which DsRed-E5, a fluorescent protein that shifts its emission spectrum from green to red over time, was expressed transgenically from the NEUROG3 locus. RESULTS In the Ngn3-Timer embryos, green-dominant cells could be readily detected by microscopy or flow cytometry and distinguished from green/red double-positive cells. When fluorescent cells were sorted into three different populations by a fluorescence-activated cell sorter, placed in culture, and then reanalyzed by flow cytometry, green-dominant cells converted to green/red double-positive cells within 6 h. The sorted cell populations were then used to determine the temporal patterns of expression for 145 transcriptional regulators in the developing pancreas. CONCLUSIONS The precise temporal resolution of this model defines the narrow window of neurogenin 3 expression in islet progenitor cells and permits sequential analyses of sorted cells as well as the testing of gene regulatory models for the differentiation of pancreatic islet cells. PMID:19478145

  12. Differentiation of breast cancer stem cells by knockdown of CD44: promising differentiation therapy

    Directory of Open Access Journals (Sweden)

    Pham Phuc V

    2011-12-01

    Full Text Available Abstract Background Breast cancer stem cells (BCSCs are the source of breast tumors. Compared with other cancer cells, cancer stem cells show high resistance to both chemotherapy and radiotherapy. Targeting of BCSCs is thus a potentially promising and effective strategy for breast cancer treatment. Differentiation therapy represents one type of cancer stem-cell-targeting therapy, aimed at attacking the stemness of cancer stem cells, thus reducing their chemo- and radioresistance. In a previous study, we showed that down-regulation of CD44 sensitized BCSCs to the anti-tumor agent doxorubicin. This study aimed to determine if CD44 knockdown caused BCSCs to differentiate into breast cancer non-stem cells (non-BCSCs. Methods We isolated a breast cancer cell population (CD44+CD24- cells from primary cultures of malignant breast tumors. These cells were sorted into four sub-populations based on their expression of CD44 and CD24 surface markers. CD44 knockdown in the BCSC population was achieved using small hairpin RNA lentivirus particles. The differentiated status of CD44 knock-down BCSCs was evaluated on the basis of changes in CD44+CD24- phenotype, tumorigenesis in NOD/SCID mice, and gene expression in relation to renewal status, metastasis, and cell cycle in comparison with BCSCs and non-BCSCs. Results Knockdown of CD44 caused BCSCs to differentiate into non-BCSCs with lower tumorigenic potential, and altered the cell cycle and expression profiles of some stem cell-related genes, making them more similar to those seen in non-BCSCs. Conclusions Knockdown of CD44 is an effective strategy for attacking the stemness of BCSCs, resulting in a loss of stemness and an increase in susceptibility to chemotherapy or radiation. The results of this study highlight a potential new strategy for breast cancer treatment through the targeting of BCSCs.

  13. Differential Effects of Tacrolimus versus Sirolimus on the Proliferation, Activation and Differentiation of Human B Cells.

    Directory of Open Access Journals (Sweden)

    Opas Traitanon

    Full Text Available The direct effect of immunosuppressive drugs calcineurin inhibitor (Tacrolimus, TAC and mTOR inhibitor (Sirolimus, SRL on B cell activation, differentiation and proliferation is not well documented. Purified human B cells from healthy volunteers were stimulated through the B Cell Receptor with Anti-IgM + anti-CD40 + IL21 in the absence / presence of TAC or SRL. A variety of parameters of B cell activity including activation, differentiation, cytokine productions and proliferation were monitored by flow cytometry. SRL at clinically relevant concentrations (6 ng/ml profoundly inhibited CD19(+ B cell proliferation compared to controls whereas TAC at similar concentrations had a minimal effect. CD27(+ memory B cells were affected more by SRL than naïve CD27- B cells. SRL effectively blocked B cell differentiation into plasma cells (CD19(+CD138(+ and Blimp1(+/Pax5(low cells even at low dose (2 ng/ml, and totally eliminated them at 6 ng/ml. SRL decreased absolute B cell counts, but the residual responding cells acquired an activated phenotype (CD25(+/CD69(+ and increased the expression of HLA-DR. SRL-treated stimulated B cells on a per cell basis were able to enhance the proliferation of allogeneic CD4(+CD25(- T cells and induce a shift toward the Th1 phenotype. Thus, SRL and TAC have different effects on B lymphocytes. These data may provide insights into the clinical use of these two agents in recipients of solid organ transplants.

  14. The role of purinergic receptors in stem cell differentiation

    Directory of Open Access Journals (Sweden)

    Constanze Kaebisch

    2015-01-01

    Full Text Available A major challenge modern society has to face is the increasing need for tissue regeneration due to degenerative diseases or tumors, but also accidents or warlike conflicts. There is great hope that stem cell-based therapies might improve current treatments of cardiovascular diseases, osteochondral defects or nerve injury due to the unique properties of stem cells such as their self-renewal and differentiation potential. Since embryonic stem cells raise severe ethical concerns and are prone to teratoma formation, adult stem cells are still in the focus of research. Emphasis is placed on cellular signaling within these cells and in between them for a better understanding of the complex processes regulating stem cell fate. One of the oldest signaling systems is based on nucleotides as ligands for purinergic receptors playing an important role in a huge variety of cellular processes such as proliferation, migration and differentiation. Besides their natural ligands, several artificial agonists and antagonists have been identified for P1 and P2 receptors and are already used as drugs. This review outlines purinergic receptor expression and signaling in stem cells metabolism. We will briefly describe current findings in embryonic and induced pluripotent stem cells as well as in cancer-, hematopoietic-, and neural crest-derived stem cells. The major focus will be placed on recent findings of purinergic signaling in mesenchymal stem cells addressed in in vitro and in vivo studies, since stem cell fate might be manipulated by this system guiding differentiation towards the desired lineage in the future.

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

    Science.gov (United States)

    Colom, Bartomeu; Jones, Philip H

    2016-12-01

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

  16. Canthin-6-one induces cell death, cell cycle arrest and differentiation in human myeloid leukemia cells.

    Science.gov (United States)

    Vieira Torquato, Heron F; Ribeiro-Filho, Antonio C; Buri, Marcus V; Araújo Júnior, Roberto T; Pimenta, Renata; de Oliveira, José Salvador R; Filho, Valdir C; Macho, Antonio; Paredes-Gamero, Edgar J; de Oliveira Martins, Domingos T

    2017-04-01

    Canthin-6-one is a natural product isolated from various plant genera and from fungi with potential antitumor activity. In the present study, we evaluate the antitumor effects of canthin-6-one in human myeloid leukemia lineages. Kasumi-1 lineage was used as a model for acute myeloid leukemia. Cells were treated with canthin-6-one and cell death, cell cycle and differentiation were evaluated in both total cells (Lin + ) and leukemia stem cell population (CD34 + CD38 - Lin -/low ). Among the human lineages tested, Kasumi-1 was the most sensitive to canthin-6-one. Canthin-6-one induced cell death with apoptotic (caspase activation, decrease of mitochondrial potential) and necrotic (lysosomal permeabilization, double labeling of annexin V/propidium iodide) characteristics. Moreover, canthin-6-one induced cell cycle arrest at G 0 /G 1 (7μM) and G 2 (45μM) evidenced by DNA content, BrdU incorporation and cyclin B1/histone 3 quantification. Canthin-6-one also promoted differentiation of Kasumi-1, evidenced by an increase in the expression of myeloid markers (CD11b and CD15) and the transcription factor PU.1. Furthermore, a reduction of the leukemic stem cell population and clonogenic capability of stem cells were observed. These results show that canthin-6-one can affect Kasumi-1 cells by promoting cell death, cell cycle arrest and cell differentiation depending on concentration used. Canthin-6-one presents an interesting cytotoxic activity against leukemic cells and represents a promising scaffold for the development of molecules for anti-leukemic applications, especially by its anti-leukemic stem cell activity. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Dexamethasone Suppresses Oxysterol-Induced Differentiation of Monocytic Cells

    Directory of Open Access Journals (Sweden)

    Yonghae Son

    2016-01-01

    Full Text Available Oxysterol like 27-hydroxycholesterol (27OHChol has been reported to induce differentiation of monocytic cells into a mature dendritic cell phenotype. We examined whether dexamethasone (Dx affects 27OHChol-induced differentiation using THP-1 cells. Treatment of monocytic cells with Dx resulted in almost complete inhibition of transcription and surface expression of CD80, CD83, and CD88 induced by 27OHChol. Elevated surface levels of MHC class I and II molecules induced by 27OHChol were reduced to basal levels by treatment with Dx. A decreased endocytosis ability caused by 27OHChol was recovered by Dx. We also examined effects of Dx on expression of CD molecules involved in atherosclerosis. Increased levels of surface protein and transcription of CD105, CD137, and CD166 by treatment with 27OHChol were significantly inhibited by cotreatment with Dx. These results indicate that Dx inhibits 27OHChol-induced differentiation of monocytic cells into a mature dendritic cell phenotype and expression of CD molecules whose levels are associated with atherosclerosis. In addition, we examined phosphorylation of AKT induced by 27OHChol and effect of Dx, where cotreatment with Dx inhibited the phosphorylation of AKT. The current study reports that Dx regulates oxysterol-mediated dendritic cell differentiation of monocytic cells.

  18. Phosphorylation dynamics during early differentiation of human embryonic stem cells

    NARCIS (Netherlands)

    van Hoof, D.; Munoz, J.; Braam, S.R.; Pinkse, M.W.H.; Linding, R.; Heck, A.J.R.; Mummery, C.L.; Krijgsveld, J.

    2009-01-01

    Pluripotent stem cells self-renew indefinitely and possess characteristic protein-protein networks that remodel during differentiation. How this occurs is poorly understood. Using quantitative mass spectrometry, we analyzed the (phospho)proteome of human embryonic stem cells (hESCs) during

  19. Endogenous collagen influences differentiation of human multipotent mesenchymal stromal cells

    NARCIS (Netherlands)

    Fernandes, H.; Mentink, A.; Bank, R.; Stoop, R.; Blitterswijk, C. van; Boer, J. de

    2010-01-01

    Human multipotent mesenchymal stromal cells (hMSCs) are multipotent cells that, in the presence of appropriate stimuli, can differentiate into different lineages such as the osteogenic, chondrogenic, and adipogenic lineages. In the presence of ascorbic acid, MSCs secrete an extracellular matrix

  20. Endogenous Collagen Influences Differentiation of Human Multipotent Mesenchymal Stromal Cells

    NARCIS (Netherlands)

    Fernandes, Hugo; Mentink, Anouk; Bank, Ruud; Stoop, Reinout; van Blitterswijk, Clemens; de Boer, Jan

    Human multipotent mesenchymal stromal cells (hMSCs) are multipotent cells that, in the presence of appropriate stimuli, can differentiate into different lineages such as the osteogenic, chondrogenic, and adipogenic lineages. In the presence of ascorbic acid, MSCs secrete an extracellular matrix

  1. Endogenous Collagen Influences Differentiation of Human Multipotent Mesenchymal Stromal Cells

    NARCIS (Netherlands)

    Fernandes, H.A.M.; Mentink-Leusink, Anouk; Bank, Ruud; Stoop, Reinout; van Blitterswijk, Clemens; de Boer, Jan

    2010-01-01

    Human multipotent mesenchymal stromal cells (hMSCs) are multipotent cells that, in the presence of appropriate stimuli, can differentiate into different lineages such as the osteogenic, chondrogenic, and adipogenic lineages. In the presence of ascorbic acid, MSCs secrete an extracellular matrix

  2. Somatic mutation and cell differentiation in neoplastic transformation

    International Nuclear Information System (INIS)

    Huberman, E.; Collart, F.R.

    1987-01-01

    In brief, the authors suggest that tumor formation may result from continuous expression of growth facilitating genes that, as a result of irreversible changes during the initiation step, are placed under the control of genes expressed during normal differentiation. Thus, to understand carcinogenesis, we must decipher the processes that lead to the acquisition of a mature phenotype in both normal and tumor cells and characterize the growth dependency of tumor cells to inducers of cell differentiation. Furthermore, the growth of a variety of tumors may be controlled through the use of inducers of maturation that activate genes located beyond the gene that is altered during tumor initiation. 22 refs., 3 figs

  3. Differential migration and proliferation of geometrical ensembles of cell clusters

    International Nuclear Information System (INIS)

    Kumar, Girish; Chen, Bo; Co, Carlos C.; Ho, Chia-Chi

    2011-01-01

    Differential cell migration and growth drives the organization of specific tissue forms and plays a critical role in embryonic development, tissue morphogenesis, and tumor invasion. Localized gradients of soluble factors and extracellular matrix have been shown to modulate cell migration and proliferation. Here we show that in addition to these factors, initial tissue geometry can feedback to generate differential proliferation, cell polarity, and migration patterns. We apply layer by layer polyelectrolyte assembly to confine multicellular organization and subsequently release cells to demonstrate the spatial patterns of cell migration and growth. The cell shapes, spreading areas, and cell-cell contacts are influenced strongly by the confining geometry. Cells within geometric ensembles are morphologically polarized. Symmetry breaking was observed for cells on the circular pattern and cells migrate toward the corners and in the direction parallel to the longest dimension of the geometric shapes. This migration pattern is disrupted when actomyosin based tension was inhibited. Cells near the edge or corner of geometric shapes proliferate while cells within do not. Regions of higher rate of cell migration corresponded to regions of concentrated growth. These findings demonstrate that multicellular organization can result in spatial patterns of migration and proliferation.

  4. Successful treatment with carboplatin and nanoparticle albumin-bound paclitaxel in a patient with pulmonary spindle cell carcinoma

    Directory of Open Access Journals (Sweden)

    Takahiro Tsuji

    2015-01-01

    Discussion: Preclinical models suggested that nab-PTX may reach the tumor microenvironment more efficiently than solvent-based paclitaxel (sb-PTX and be preferentially taken up by cancer cells. Considering that there is no effective treatment for patients with pulmonary SpCC, nab-PTX may merit further investigation in patients with pulmonary SpCC.

  5. Directed neuronal differentiation of human embryonic stem cells

    Directory of Open Access Journals (Sweden)

    Noggle Scott A

    2003-10-01

    Full Text Available Abstract Background We have developed a culture system for the efficient and directed differentiation of human embryonic stem cells (HESCs to neural precursors and neurons. HESC were maintained by manual passaging and were differentiated to a morphologically distinct OCT-4+/SSEA-4- monolayer cell type prior to the derivation of embryoid bodies. Embryoid bodies were grown in suspension in serum free conditions, in the presence of 50% conditioned medium from the human hepatocarcinoma cell line HepG2 (MedII. Results A neural precursor population was observed within HESC derived serum free embryoid bodies cultured in MedII conditioned medium, around 7–10 days after derivation. The neural precursors were organized into rosettes comprised of a central cavity surrounded by ring of cells, 4 to 8 cells in width. The central cells within rosettes were proliferating, as indicated by the presence of condensed mitotic chromosomes and by phosphoHistone H3 immunostaining. When plated and maintained in adherent culture, the rosettes of neural precursors were surrounded by large interwoven networks of neurites. Immunostaining demonstrated the expression of nestin in rosettes and associated non-neuronal cell types, and a radial expression of Map-2 in rosettes. Differentiated neurons expressed the markers Map-2 and Neurofilament H, and a subpopulation of the neurons expressed tyrosine hydroxylase, a marker for dopaminergic neurons. Conclusion This novel directed differentiation approach led to the efficient derivation of neuronal cultures from HESCs, including the differentiation of tyrosine hydroxylase expressing neurons. HESC were morphologically differentiated to a monolayer OCT-4+ cell type, which was used to derive embryoid bodies directly into serum free conditions. Exposure to the MedII conditioned medium enhanced the derivation of neural precursors, the first example of the effect of this conditioned medium on HESC.

  6. A defect-driven diagnostic method for machine tool spindles.

    Science.gov (United States)

    Vogl, Gregory W; Donmez, M Alkan

    2015-01-01

    Simple vibration-based metrics are, in many cases, insufficient to diagnose machine tool spindle condition. These metrics couple defect-based motion with spindle dynamics; diagnostics should be defect-driven. A new method and spindle condition estimation device (SCED) were developed to acquire data and to separate system dynamics from defect geometry. Based on this method, a spindle condition metric relying only on defect geometry is proposed. Application of the SCED on various milling and turning spindles shows that the new approach is robust for diagnosing the machine tool spindle condition.

  7. Osteogenic differentiation of human dental papilla mesenchymal cells

    International Nuclear Information System (INIS)

    Ikeda, Etsuko; Hirose, Motohiro; Kotobuki, Noriko; Shimaoka, Hideki; Tadokoro, Mika; Maeda, Masahiko; Hayashi, Yoshiko; Kirita, Tadaaki; Ohgushi, Hajime

    2006-01-01

    We isolated dental papilla from impacted human molar and proliferated adherent fibroblastic cells after collagenase treatment of the papilla. The cells were negative for hematopoietic markers but positive for CD29, CD44, CD90, CD105, and CD166. When the cells were further cultured in the presence of β-glycerophosphate, ascorbic acid, and dexamethasone for 14 days, mineralized areas together with osteogenic differentiation evidenced by high alkaline phosphatase activity and osteocalcin contents were observed. The differentiation was confirmed at both protein and gene expression levels. The cells can also be cryopreserved and, after thawing, could show in vivo bone-forming capability. These results indicate that mesenchymal type cells localize in dental papilla and that the cells can be culture expanded/utilized for bone tissue engineering

  8. Transplantation Dose Alters the Differentiation Program of Hematopoietic Stem Cells.

    Science.gov (United States)

    Brewer, Casey; Chu, Elizabeth; Chin, Mike; Lu, Rong

    2016-05-24

    Hematopoietic stem cell (HSC) transplantation is the most prevalent stem cell therapy, but it remains a risky procedure. To improve this treatment, it is important to understand how transplanted stem cells rebuild the blood and immune systems and how this process is impacted by transplantation variables such as the HSC dose. Here, we find that, in the long term following transplantation, 70%-80% of donor-HSC-derived clones do not produce all measured blood cell types. High HSC doses lead to more clones that exhibit balanced lymphocyte production, whereas low doses produce more T-cell-specialized clones. High HSC doses also produce significantly higher proportions of early-differentiating clones compared to low doses. These complex differentiation behaviors uncover the clonal-level regeneration dynamics of hematopoietic regeneration and suggest that transplantation dose can be exploited to improve stem cell therapy. Copyright © 2016 The Author(s). Published by Elsevier Inc. All rights reserved.

  9. Effects of ionizing radiation on differentiation of murine bone marrow cells into mast cells

    International Nuclear Information System (INIS)

    Murakami, Sho; Yoshino, Hironori; Ishikawa, Junya; Yamaguchi, Masaru; Tsujiguchi, Takakiyo; Nishiyama, Ayaka; Yokoyama, Kouki; Kashiwakura, Ikuo

    2015-01-01

    Mast cells, immune effector cells produced from bone marrow cells, play a major role in immunoglobulin E–mediated allergic responses. Ionizing radiation affects the functions of mast cells, which are involved in radiation-induced tissue damage. However, whether ionizing radiation affects the differential induction of mast cells is unknown. Here we investigated whether bone marrow cells of X-irradiated mice differentiated into mast cells. To induce mast cells, bone marrow cells from X-irradiated and unirradiated mice were cultured in the presence of cytokines required for mast cell induction. Although irradiation at 0.5 Gy and 2 Gy decreased the number of bone marrow cells 1 day post-irradiation, the cultured bone marrow cells of X-irradiated and unirradiated mice both expressed mast cell–related cell-surface antigens. However, the percentage of mast cells in the irradiated group was lower than in the unirradiated group. Similar decreases in the percentage of mast cells induced in the presence of X-irradiation were observed 10 days post irradiation, although the number of bone marrow cells in irradiated mice had recovered by this time. Analysis of mast cell function showed that degranulation of mast cells after immunoglobulin E–mediated allergen recognition was significantly higher in the X-irradiated group compared with in the unirradiated group. In conclusion, bone marrow cells of X-irradiated mice differentiated into mast cells, but ionizing radiation affected the differentiation efficiency and function of mast cells. (author)

  10. Glutathione, cell proliferation and differentiation | Ashtiani | African ...

    African Journals Online (AJOL)

    All organisms require an equivalent source for living. Reduced glutathione is the most abundant thiol containing protein in mammalian cells and organs. Glutathione was discovered by Hopkins in 1924 who published his findings in JBC. It is a three peptide containing glutamic acid, cystein and glycin and is found in reduced ...

  11. Effect of cell density on adipogenic differentiation of mesenchymal stem cells

    International Nuclear Information System (INIS)

    Lu, Hongxu; Guo, Likun; Wozniak, Michal J.; Kawazoe, Naoki; Tateishi, Tetsuya; Zhang, Xingdong; Chen, Guoping

    2009-01-01

    The effect of cell density on the adipogenic differentiation of human bone marrow-derived mesenchymal stem cells (MSCs) was investigated by using a patterning technique to induce the formation of a cell density gradient on a micropatterned surface. The adipogenic differentiation of MSCs at a density gradient from 5 x 10 3 to 3 x 10 4 cells/cm 2 was examined. Lipid vacuoles were observed at all cell densities after 1-3 weeks of culture in adipogenic differentiation medium although the lipid vacuoles were scarce at the low cell density and abundant at the high cell density. Real-time RT-PCR analysis showed that adipogenesis marker genes encoding peroxisome proliferator-activated receptor γ2 (PPARγ2), lipoprotein lipase (LPL), and fatty acid binding protein-4 (FABP4) were detected in the MSCs cultured at all cell densities. The results suggest that there was no apparent effect of cell density on the adipogenic differentiation of human MSCs.

  12. Cenp-meta is required for sustained spindle checkpoint

    Directory of Open Access Journals (Sweden)

    Thomas Rubin

    2014-05-01

    Full Text Available Cenp-E is a kinesin-like motor protein required for efficient end-on attachment of kinetochores to the spindle microtubules. Cenp-E immunodepletion in Xenopus mitotic extracts results in the loss of mitotic arrest and massive chromosome missegregation, whereas its depletion in mammalian cells leads to chromosome segregation defects despite the presence of a functional spindle assembly checkpoint (SAC. Cenp-meta has previously been reported to be the Drosophila homolog of vertebrate Cenp-E. In this study, we show that cenp-metaΔ mutant neuroblasts arrest in mitosis when treated with colchicine. cenp-metaΔ mutant cells display a mitotic delay. Yet, despite the persistence of the two checkpoint proteins Mad2 and BubR1 on unattached kinetochores, these cells eventually enter anaphase and give rise to highly aneuploid daughter cells. Indeed, we find that cenp-metaΔ mutant cells display a slow but continuous degradation of cyclin B, which eventually triggers the mitotic exit observed. Thus, our data provide evidence for a role of Cenp-meta in sustaining the SAC response.

  13. Prostate cancer cells induce osteoblastic differentiation via semaphorin 3A.

    Science.gov (United States)

    Liu, Fuzhou; Shen, Weiwei; Qiu, Hao; Hu, Xu; Zhang, Chao; Chu, Tongwei

    2015-03-01

    Prostate cancer metastasis to bone is the second most commonly diagnosed malignant disease among men worldwide. Such metastatic disease is characterized by the presence of osteoblastic bone lesions, and is associated with high rates of mortality. However, the various mechanisms involved in prostate cancer-induced osteoblastic differentiation have not been fully explored. Semaphorin 3A (Sema 3A) is a newly identified regulator of bone metabolism which stimulates differentiation of pre-osteoblastic cells under physiological conditions. We investigated in this study whether prostate cancer cells can mediate osteoblastic activity through Sema 3A. We cultured osteoprogenitor MC3T3-E1 cells in prostate cancer-conditioned medium, and analyzed levels of Sema 3A protein in diverse prostate cancer cell lines to identify cell lines in which Sema 3A production showed a positive correlation with osteo-stimulation. C4-2 cells were stably transfected with Sema 3A short hairpin RNA to further determine whether Sema 3A contributes to the ability of C4-2 cells to induce osteoblastic differentiation. Down-regulation of Sema 3A expression decreased indicators of C4-2 CM-induced osteoblastic differentiation, including alkaline phosphatase production and mineralization. Additionally, silencing or neutralizing Sema 3A in C4-2 cells resulted in diminished β-catenin expression in osteogenitor MC3T3-E1 cells. Our results suggest that prostate cancer-induced osteoblastic differentiation is at least partially mediated by Sema 3A, and may be regulated by the β-catenin signalling pathway. Sema 3A may represent a novel target for treatment of prostate cancer-induced osteoblastic lesions. © 2014 Wiley Periodicals, Inc.

  14. Characterisation of insulin-producing cells differentiated from tonsil derived mesenchymal stem cells.

    Science.gov (United States)

    Kim, So-Yeon; Kim, Ye-Ryung; Park, Woo-Jae; Kim, Han Su; Jung, Sung-Chul; Woo, So-Youn; Jo, Inho; Ryu, Kyung-Ha; Park, Joo-Won

    2015-01-01

    Tonsil-derived (T-) mesenchymal stem cells (MSCs) display mutilineage differentiation potential and self-renewal capacity and have potential as a banking source. Diabetes mellitus is a prevalent disease in modern society, and the transplantation of pancreatic progenitor cells or various stem cell-derived insulin-secreting cells has been suggested as a novel therapy for diabetes. The potential of T-MSCs to trans-differentiate into pancreatic progenitor cells or insulin-secreting cells has not yet been investigated. We examined the potential of human T-MSCs to trans-differentiate into pancreatic islet cells using two different methods based on β-mercaptoethanol and insulin-transferin-selenium, respectively. First, we compared the efficacy of the two methods for inducing differentiation into insulin-producing cells. We demonstrated that the insulin-transferin-selenium method is more efficient for inducing differentiation into insulin-secreting cells regardless of the source of the MSCs. Second, we compared the differentiation potential of two different MSC types: T-MSCs and adipose-derived MSCs (A-MSCs). T-MSCs had a differentiation capacity similar to that of A-MSCs and were capable of secreting insulin in response to glucose concentration. Islet-like clusters differentiated from T-MSCs had lower synaptotagmin-3, -5, -7, and -8 levels, and consequently lower secreted insulin levels than cells differentiated from A-MSCs. These results imply that T-MSCs can differentiate into functional pancreatic islet-like cells and could provide a novel, alternative cell therapy for diabetes mellitus. Copyright © 2015 International Society of Differentiation. Published by Elsevier B.V. All rights reserved.

  15. The Role of Lymphatic Niches in T Cell Differentiation

    Science.gov (United States)

    Capece, Tara; Kim, Minsoo

    2016-01-01

    Long-term immunity to many viral and bacterial pathogens requires CD8+ memory T cell development, and the induction of long-lasting CD8+ memory T cells from a naïve, undifferentiated state is a major goal of vaccine design. Formation of the memory CD8+ T cell compartment is highly dependent on the early activation cues received by naïve CD8+ T cells during primary infection. This review aims to highlight the cellularity of various niches within the lymph node and emphasize recent evidence suggesting that distinct types of T cell activation and differentiation occur within different immune contexts in lymphoid organs. PMID:27306645

  16. Mechanisms of dealing with DNA damage in terminally differentiated cells

    Energy Technology Data Exchange (ETDEWEB)

    Fortini, P. [Department of Environment and Primary Prevention, Istituto Superiore di Sanita, Viale Regina Elena 299, 00161 Rome (Italy); Dogliotti, E., E-mail: eugenia.dogliotti@iss.it [Department of Environment and Primary Prevention, Istituto Superiore di Sanita, Viale Regina Elena 299, 00161 Rome (Italy)

    2010-03-01

    To protect genomic integrity living cells that are continuously exposed to DNA-damaging insults are equipped with an efficient defence mechanism termed the DNA damage response. Its function is to eliminate DNA damage through DNA repair and to remove damaged cells by apoptosis. The DNA damage response has been investigated mainly in proliferating cells, in which the cell cycle machinery is integrated with the DNA damage signalling. The current knowledge of the mechanisms of DNA repair, DNA damage signalling and cell death of post-mitotic cells that have undergone irreversible cell cycle withdrawal will be reviewed. Evidence will be provided that the protection of the genome integrity in terminally differentiated cells is achieved by different strategies than in proliferating cells.

  17. Chronology of endocrine differentiation and beta-cell neogenesis.

    Science.gov (United States)

    Miyatsuka, Takeshi

    2016-01-01

    Diabetes is a chronic and incurable disease, which results from absolute or relative insulin insufficiency. Therefore, pancreatic beta cells, which are the only type of cell that expresses insulin, is considered to be a potential target for the cure of diabetes. Although the findings regarding beta-cell neogenesis during pancreas development have been exploited to induce insulin-producing cells from non-beta cells, there are still many hurdles towards generating fully functional beta cells that can produce high levels of insulin and respond to physiological signals. To overcome these problems, a solid understanding of pancreas development and beta-cell formation is required, and several mouse models have been developed to reveal the unique features of each endocrine cell type at distinct developmental time points. Here I review our understanding of pancreas development and endocrine differentiation focusing on recent progresses in improving temporal cell labeling in vivo.

  18. Mechanisms of dealing with DNA damage in terminally differentiated cells

    International Nuclear Information System (INIS)

    Fortini, P.; Dogliotti, E.

    2010-01-01

    To protect genomic integrity living cells that are continuously exposed to DNA-damaging insults are equipped with an efficient defence mechanism termed the DNA damage response. Its function is to eliminate DNA damage through DNA repair and to remove damaged cells by apoptosis. The DNA damage response has been investigated mainly in proliferating cells, in which the cell cycle machinery is integrated with the DNA damage signalling. The current knowledge of the mechanisms of DNA repair, DNA damage signalling and cell death of post-mitotic cells that have undergone irreversible cell cycle withdrawal will be reviewed. Evidence will be provided that the protection of the genome integrity in terminally differentiated cells is achieved by different strategies than in proliferating cells.

  19. Effect of Ultrasonic Vibration on Proliferation and Differentiation of Cells

    Directory of Open Access Journals (Sweden)

    Haruka Hino

    2016-12-01

    Full Text Available The effect of mechanical stimulation of vibration on proliferation and differentiation of cells has been studied in vitro. To apply the vibration on the cells, a piezoelectric element was attached on the outside surface of the bottom of the culture plate of six wells. The piezoelectric element was vibrated by sinusoidally alternating voltage at 1.0 MHz generated by a function generator. Five kinds of cells were used in the experiment: C2C12 (mouse myoblast cell, L929 (fibroblast connective tissue of mouse, Hepa1-6 (mouse hepatoma cell, HUVEC (human umbilical vein endothelial cell, and Neuro-2a (mouse neural crest-derived cell line. After the incubation for 24 hours, cells were exposed to the ultrasonic vibration intermittently for three days: for thirty minutes per day. At the end of the experiment, the number of cells was counted by colorimetric method with a microplate photometer. In the case of Neuro-2a, the total length of the neurite was calculated at the microscopic image. The experimental study shows following results. Cells are exfoliated by the strong vibration. Proliferation and differentiation of cells are accelerated with mild vibration. The optimum intensity of vibration depends on the kind of cells.

  20. Induction of differentiation of murine embryonal carcinoma cells by ouabain

    International Nuclear Information System (INIS)

    Zimmerman, B.T.

    1986-01-01

    Embryonal carcinoma (EC) cells can be induced to differentiate by ouabain at concentrations which inhibit Na + , K + -ATPase activity as measured by inhibition of 86 Rb + uptake. Since the pharmacologic action of ouabain is thought to be specific, the authors investigated the role of Na + , K + -ATPase inhibition and specific metabolic consequences of this inhibition in the induction of EC differentiation, and explored whether this might be a common mode of action for a variety of structurally diverse inducers. The Na + , K + -ATPase maintains ionic gradients in cells. However, results of studies utilizing specific ionophores, channel blockers, and media deficient in specific components failed to demonstrate a consistent role for ion flux or concentration in the differentiation process. The Na + , K + -ATPase is a major consumer of ATP. They therefore examined the effect of Na + , K + -ATPase inhibition on the adenylate energy charge as measured by high performance liquid chromatography of adenylate nucleotides. Ouabain was found to significantly decrease the energy charge in sensitive cells suggesting a role for suppression of ATP turnover is triggering differentiation. However, direct inhibition of glycolysis also induced differentiation without decreasing the energy charge, suggesting that reduction of the energy charge is not a common mechanism for induction of differentiation of EC

  1. Effects of Culture Substrate Made of Poly(N-isopropylacrylamide-co-acrylic acid Microgels on Osteogenic Differentiation of Mesenchymal Stem Cells

    Directory of Open Access Journals (Sweden)

    Zhuojun Dai

    2016-09-01

    Full Text Available Poly(N-isopropylacrylamide (PNIPAM-based polymers and gels are widely known and studied for their thermoresponsive property. In the biomaterials category, they are regarded as a potential cell culture substrate, not only because of their biocompatibility, but also their special character of allowing controlled detachment of cells via temperature stimulus. Previous research about PNIPAM-based substrates mostly concentrated on their effects in cell adhesion and proliferation. In this study, however, we investigate the influence of the PNIPAM-based substrate on the differentiation capacity of stem cells. Especially, we choose P(NIPAM-AA microgels as a culture dish coating and mesenchymal stem cells (MSCs are cultured on top of the microgels. Interestingly, we find that the morphology of MSCs changes remarkably on a microgel-coated surface, from the original spindle form to a more stretched and elongated cell shape. Accompanied by the alternation in morphology, the expression of several osteogenesis-related genes is elevated even without inducing factors. In the presence of full osteogenic medium, MSCs on a microgel substrate show an enhancement in the expression level of osteopontin and alizarin red staining signals, indicating the physical property of substrate has a direct effect on MSCs differentiation.

  2. Regulation of T cell differentiation and function by EZH2

    Directory of Open Access Journals (Sweden)

    THEODOROS KARANTANOS

    2016-05-01

    Full Text Available The enhancer of zeste homologue 2 (EZH2, one of the polycomb group (PcG proteins, is the catalytic subunit of Polycomb-repressive complex 2 (PRC2 and induces the trimethylation of the histone H3 lysine 27 (H3K27me3 promoting epigenetic gene silencing. EZH2 contains a SET domain promoting the methyltransferase activity while the three other protein components of PRC2, namely EED, SUZ12 and RpAp46/48 induce compaction of the chromatin permitting EZH2 enzymatic activity. Numerous studies highlight the role of this evolutionary conserved protein as a master regulator of differentiation in humans involved in the repression of the homeotic (Hox gene and the inactivation of X-chromosome. Through its effects in the epigenetic regulation of critical genes, EZH2 has been strongly linked to cell cycle progression, stem cell pluripotency and cancer biology. Most recently, EZH2 has been associated with hematopoietic stem cell proliferation and differentiation, thymopoiesis and lymphopoiesis. Several studies have evaluated the role of EZH2 in the regulation of T cell differentiation and plasticity as well as its implications in the development of autoimmune diseases and graft versus host disease (GvHD. In this review we will briefly summarize the current knowledge regarding the role of EZH2 in the regulation of T cell differentiation, effector function and homing in the tumor microenvironment and we will discuss possible therapeutic targeting of EZH2 in order to alter T cell immune functions.

  3. Pericytes Stimulate Oligodendrocyte Progenitor Cell Differentiation during CNS Remyelination

    Directory of Open Access Journals (Sweden)

    Alerie Guzman De La Fuente

    2017-08-01

    Full Text Available The role of the neurovascular niche in CNS myelin regeneration is incompletely understood. Here, we show that, upon demyelination, CNS-resident pericytes (PCs proliferate, and parenchymal non-vessel-associated PC-like cells (PLCs rapidly develop. During remyelination, mature oligodendrocytes were found in close proximity to PCs. In Pdgfbret/ret mice, which have reduced PC numbers, oligodendrocyte progenitor cell (OPC differentiation was delayed, although remyelination proceeded to completion. PC-conditioned medium accelerated and enhanced OPC differentiation in vitro and increased the rate of remyelination in an ex vivo cerebellar slice model of demyelination. We identified Lama2 as a PC-derived factor that promotes OPC differentiation. Thus, the functional role of PCs is not restricted to vascular homeostasis but includes the modulation of adult CNS progenitor cells involved in regeneration.

  4. Expression of assayable residual stem cell damage in erythroid differentiation

    International Nuclear Information System (INIS)

    Huebner, G.E.; Miller, M.E.; Cronkite, E.P.

    1985-01-01

    In rodents, residual damage is inducible in hematopoietic stem cells by exposure to ionizing radiation or alkylating agents. This damage can b e assayed in mice by transferring bone marrow into lethally irradiated syngeneic recipients and subsequently measuring the incremental increase of-( 125 I)iodo-2'-deoxyuridine incorporation in spleens. In this study, bone marrow from mice treated 3 weeks previously with Methylnitrosourea (50 mg/kg) or 450 rad was injected into recipients in order to determine possible residual effects of treatment of erythroid cell differentiation following stem cell seeding. Such effects were detected by a reduced amount of 59 Fe incorporation into spleens, thus indicatin g transfer of residual stem cell damage to differentiating cells. (orig.)

  5. Lineage-specific interface proteins match up the cell cycle and differentiation in embryo stem cells

    DEFF Research Database (Denmark)

    Re, Angela; Workman, Christopher; Waldron, Levi

    2014-01-01

    The shortage of molecular information on cell cycle changes along embryonic stem cell (ESC) differentiation prompts an in silico approach, which may provide a novel way to identify candidate genes or mechanisms acting in coordinating the two programs. We analyzed germ layer specific gene expression...... changes during the cell cycle and ESC differentiation by combining four human cell cycle transcriptome profiles with thirteen in vitro human ESC differentiation studies. To detect cross-talk mechanisms we then integrated the transcriptome data that displayed differential regulation with protein...... interaction data. A new class of non-transcriptionally regulated genes was identified, encoding proteins which interact systematically with proteins corresponding to genes regulated during the cell cycle or cell differentiation, and which therefore can be seen as interface proteins coordinating the two...

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

    Science.gov (United States)

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

    2014-06-01

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

  7. An engineered cell-imprinted substrate directs osteogenic differentiation in stem cells

    DEFF Research Database (Denmark)

    Kamguyan, Khorshid; Katbab, Ali Asghar; Mahmoudi, Morteza

    2018-01-01

    A cell-imprinted poly(dimethylsiloxane)/hydroxyapatite nanocomposite substrate was fabricated to engage topographical, mechanical, and chemical signals to stimulate and boost stem cell osteogenic differentiation. The physicochemical properties of the fabricated substrates, with nanoscale resolution...

  8. Redox environment in stem and differentiated cells: A quantitative approach.

    Science.gov (United States)

    Lyublinskaya, O G; Ivanova, Ju S; Pugovkina, N A; Kozhukharova, I V; Kovaleva, Z V; Shatrova, A N; Aksenov, N D; Zenin, V V; Kaulin, Yu A; Gamaley, I A; Nikolsky, N N

    2017-08-01

    Stem cells are believed to maintain a specific intracellular redox status through a combination of enhanced removal capacity and limited production of ROS. In the present study, we challenge this assumption by developing a quantitative approach for the analysis of the pro- and antioxidant ability of human embryonic stem cells in comparison with their differentiated descendants, as well as adult stem and non-stem cells. Our measurements showed that embryonic stem cells are characterized by low ROS level, low rate of extracellular hydrogen peroxide removal and low threshold for peroxide-induced cytotoxicity. However, biochemical normalization of these parameters to cell volume/protein leads to matching of normalized values in stem and differentiated cells and shows that tested in the present study cells (human embryonic stem cells and their fibroblast-like progenies, adult mesenchymal stem cells, lymphocytes, HeLa) maintain similar intracellular redox status. Based on these observations, we propose to use ROS concentration averaged over the cell volume instead of ROS level as a measure of intracellular redox balance. We show that attempts to use ROS level for comparative analysis of redox status of morphologically different cells could lead to false conclusions. Methods for the assessment of ROS concentration based on flow cytometry analysis with the use of H 2 DCFDA dye and HyPer, genetically encoded probe for hydrogen peroxide, are discussed. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  9. Erythroid differentiation of human induced pluripotent stem cells is independent of donor cell type of origin.

    Science.gov (United States)

    Dorn, Isabel; Klich, Katharina; Arauzo-Bravo, Marcos J; Radstaak, Martina; Santourlidis, Simeon; Ghanjati, Foued; Radke, Teja F; Psathaki, Olympia E; Hargus, Gunnar; Kramer, Jan; Einhaus, Martin; Kim, Jeong Beom; Kögler, Gesine; Wernet, Peter; Schöler, Hans R; Schlenke, Peter; Zaehres, Holm

    2015-01-01

    Epigenetic memory in induced pluripotent stem cells, which is related to the somatic cell type of origin of the stem cells, might lead to variations in the differentiation capacities of the pluripotent stem cells. In this context, induced pluripotent stem cells from human CD34(+) hematopoietic stem cells might be more suitable for hematopoietic differentiation than the commonly used fibroblast-derived induced pluripotent stem cells. To investigate the influence of an epigenetic memory on the ex vivo expansion of induced pluripotent stem cells into erythroid cells, we compared induced pluripotent stem cells from human neural stem cells and human cord blood-derived CD34(+) hematopoietic stem cells and evaluated their potential for differentiation into hematopoietic progenitor and mature red blood cells. Although genome-wide DNA methylation profiling at all promoter regions demonstrates that the epigenetic memory of induced pluripotent stem cells is influenced by the somatic cell type of origin of the stem cells, we found a similar hematopoietic induction potential and erythroid differentiation pattern of induced pluripotent stem cells of different somatic cell origin. All human induced pluripotent stem cell lines showed terminal maturation into normoblasts and enucleated reticulocytes, producing predominantly fetal hemoglobin. Differences were only observed in the growth rate of erythroid cells, which was slightly higher in the induced pluripotent stem cells derived from CD34(+) hematopoietic stem cells. More detailed methylation analysis of the hematopoietic and erythroid promoters identified similar CpG methylation levels in the induced pluripotent stem cell lines derived from CD34(+) cells and those derived from neural stem cells, which confirms their comparable erythroid differentiation potential. Copyright© Ferrata Storti Foundation.

  10. Differentiation of Mouse Embryonic Stem Cells into Ventral Foregut Precursors

    DEFF Research Database (Denmark)

    Rothová, Michaela; Hölzenspies, Jurriaan J; Livigni, Alessandra

    2016-01-01

    Anterior definitive endoderm (ADE), the ventral foregut precursor, is both an important embryonic signaling center and a unique multipotent precursor of liver, pancreas, and other organs. Here, a method is described for the differentiation of mouse embryonic stem cells (mESCs) to definitive...... endoderm with pronounced anterior character. ADE-containing cultures can be produced in vitro by suspension (embryoid body) culture or in a serum-free adherent monolayer culture. ESC-derived ADE cells are committed to endodermal fates and can undergo further differentiation in vitro towards ventral foregut...

  11. Epigenetic heterochromatin markers distinguish terminally differentiated leukocytes from incompletely differentiated leukemia cells in human blood

    Czech Academy of Sciences Publication Activity Database

    Popova, Evgenya Y.; Claxton, David F.; Lukášová, Emilie; Bird, Philip I.; Grigoryev, Sergei A.

    2006-01-01

    Roč. 34, č. 4 (2006), s. 453-462 ISSN 0301-472X R&D Projects: GA AV ČR(CZ) 1QS500040508 Institutional research plan: CEZ:AV0Z50040507 Keywords : terminal cell differentiation * chromatin structure * chronic myeloid leukemia Subject RIV: BO - Biophysics Impact factor: 3.408, year: 2006

  12. Cell cycle-dependent differentiation dynamics balances growth and endocrine differentiation in the pancreas

    DEFF Research Database (Denmark)

    Kim, Yung Hae; Larsen, Hjalte List; Rué, Paul

    2015-01-01

    Organogenesis relies on the spatiotemporal balancing of differentiation and proliferation driven by an expanding pool of progenitor cells. In the mouse pancreas, lineage tracing at the population level has shown that the expanding pancreas progenitors can initially give rise to all endocrine...

  13. Differentiation state determines neural effects on microvascular endothelial cells

    International Nuclear Information System (INIS)

    Muffley, Lara A.; Pan, Shin-Chen; Smith, Andria N.; Ga, Maricar; Hocking, Anne M.; Gibran, Nicole S.

    2012-01-01

    Growing evidence indicates that nerves and capillaries interact paracrinely in uninjured skin and cutaneous wounds. Although mature neurons are the predominant neural cell in the skin, neural progenitor cells have also been detected in uninjured adult skin. The aim of this study was to characterize differential paracrine effects of neural progenitor cells and mature sensory neurons on dermal microvascular endothelial cells. Our results suggest that neural progenitor cells and mature sensory neurons have unique secretory profiles and distinct effects on dermal microvascular endothelial cell proliferation, migration, and nitric oxide production. Neural progenitor cells and dorsal root ganglion neurons secrete different proteins related to angiogenesis. Specific to neural progenitor cells were dipeptidyl peptidase-4, IGFBP-2, pentraxin-3, serpin f1, TIMP-1, TIMP-4 and VEGF. In contrast, endostatin, FGF-1, MCP-1 and thrombospondin-2 were specific to dorsal root ganglion neurons. Microvascular endothelial cell proliferation was inhibited by dorsal root ganglion neurons but unaffected by neural progenitor cells. In contrast, microvascular endothelial cell migration in a scratch wound assay was inhibited by neural progenitor cells and unaffected by dorsal root ganglion neurons. In addition, nitric oxide production by microvascular endothelial cells was increased by dorsal root ganglion neurons but unaffected by neural progenitor cells. -- Highlights: ► Dorsal root ganglion neurons, not neural progenitor cells, regulate microvascular endothelial cell proliferation. ► Neural progenitor cells, not dorsal root ganglion neurons, regulate microvascular endothelial cell migration. ► Neural progenitor cells and dorsal root ganglion neurons do not effect microvascular endothelial tube formation. ► Dorsal root ganglion neurons, not neural progenitor cells, regulate microvascular endothelial cell production of nitric oxide. ► Neural progenitor cells and dorsal root

  14. Differentiation of human mesenchymal stem cell spheroids under microgravity conditions

    Directory of Open Access Journals (Sweden)

    Wolfgang H Cerwinka

    2012-01-01

    Full Text Available To develop and characterize a novel cell culture method for the generation of undifferentiated and differentiated human mesenchymal stem cell 3D structures, we utilized the RWV system with a gelatin-based scaffold. 3 × 106 cells generated homogeneous spheroids and maximum spheroid loading was accomplished after 3 days of culture. Spheroids cultured in undifferentiated spheroids of 3 and 10 days retained expression of CD44, without expression of differentiation markers. Spheroids cultured in adipogenic and osteogenic differentiation media exhibited oil red O staining and von Kossa staining, respectively. Further characterization of osteogenic lineage, showed that 10 day spheroids exhibited stronger calcification than any other experimental group corresponding with significant expression of vitamin D receptor, alkaline phosphatase, and ERp60 . In conclusion this study describes a novel RWV culture method that allowed efficacious engineering of undifferentiated human mesenchymal stem cell spheroids and rapid osteogenic differentiation. The use of gelatin scaffolds holds promise to design implantable stem cell tissue of various sizes and shapes for future regenerative treatment.

  15. Regulation of T Cell Differentiation and Function by EZH2

    Science.gov (United States)

    Karantanos, Theodoros; Christofides, Anthos; Bardhan, Kankana; Li, Lequn; Boussiotis, Vassiliki A.

    2016-01-01

    The enhancer of zeste homolog 2 (EZH2), one of the polycomb-group proteins, is the catalytic subunit of Polycomb-repressive complex 2 (PRC2) and induces the trimethylation of the histone H3 lysine 27 (H3K27me3) promoting epigenetic gene silencing. EZH2 contains a SET domain promoting the methyltransferase activity, while the three other protein components of PRC2, namely EED, SUZ12, and RpAp46/48, induce compaction of the chromatin permitting EZH2 enzymatic activity. Numerous studies highlight the role of this evolutionary conserved protein as a master regulator of differentiation in humans involved in the repression of the homeotic gene and the inactivation of X-chromosome. Through its effects in the epigenetic regulation of critical genes, EZH2 has been strongly linked to cell cycle progression, stem cell pluripotency, and cancer biology, being currently at the cutting edge of research. Most recently, EZH2 has been associated with hematopoietic stem cell proliferation and differentiation, thymopoiesis and lymphopoiesis. Several studies have evaluated the role of EZH2 in the regulation of T cell differentiation and plasticity as well as its implications in the development of autoimmune diseases and graft-versus-host disease (GVHD). The aim of this review is to summarize the current knowledge regarding the role of EZH2 in the regulation of the differentiation and function of T cells focusing on possible applications in various immune-mediated conditions, including autoimmune disorders and GVHD. PMID:27199994

  16. Transcription factor interplay in T helper cell differentiation

    Science.gov (United States)

    Evans, Catherine M.

    2013-01-01

    The differentiation of CD4 helper T cells into specialized effector lineages has provided a powerful model for understanding immune cell differentiation. Distinct lineages have been defined by differential expression of signature cytokines and the lineage-specifying transcription factors necessary and sufficient for their production. The traditional paradigm of differentiation towards Th1 and Th2 subtypes driven by T-bet and GATA3, respectively, has been extended to incorporate additional T cell lineages and transcriptional regulators. Technological advances have expanded our view of these lineage-specifying transcription factors to the whole genome and revealed unexpected interplay between them. From these data, it is becoming clear that lineage specification is more complex and plastic than previous models might have suggested. Here, we present an overview of the different forms of transcription factor interplay that have been identified and how T cell phenotypes arise as a product of this interplay within complex regulatory networks. We also suggest experimental strategies that will provide further insight into the mechanisms that underlie T cell lineage specification and plasticity. PMID:23878131

  17. Proliferation of differentiated glial cells in the brain stem

    Directory of Open Access Journals (Sweden)

    P.C. Barradas

    1998-02-01

    Full Text Available Classical studies of macroglial proliferation in muride rodents have provided conflicting evidence concerning the proliferating capabilities of oligodendrocytes and microglia. Furthermore, little information has been obtained in other mammalian orders and very little is known about glial cell proliferation and differentiation in the subclass Metatheria although valuable knowledge may be obtained from the protracted period of central nervous system maturation in these forms. Thus, we have studied the proliferative capacity of phenotypically identified brain stem oligodendrocytes by tritiated thymidine radioautography and have compared it with known features of oligodendroglial differentiation as well as with proliferation of microglia in the opossum Didelphis marsupialis. We have detected a previously undescribed ephemeral, regionally heterogeneous proliferation of oligodendrocytes expressing the actin-binding, ensheathment-related protein 2'3'-cyclic nucleotide 3'-phosphodiesterase (CNPase, that is not necessarily related to the known regional and temporal heterogeneity of expression of CNPase in cell bodies. On the other hand, proliferation of microglia tagged by the binding of Griffonia simplicifolia B4 isolectin, which recognizes an alpha-D-galactosyl-bearing glycoprotein of the plasma membrane of macrophages/microglia, is known to be long lasting, showing no regional heterogeneity and being found amongst both ameboid and differentiated ramified cells, although at different rates. The functional significance of the proliferative behavior of these differentiated cells is unknown but may provide a low-grade cell renewal in the normal brain and may be augmented under pathological conditions.

  18. Transcription factor interplay in T helper cell differentiation.

    Science.gov (United States)

    Evans, Catherine M; Jenner, Richard G

    2013-11-01

    The differentiation of CD4 helper T cells into specialized effector lineages has provided a powerful model for understanding immune cell differentiation. Distinct lineages have been defined by differential expression of signature cytokines and the lineage-specifying transcription factors necessary and sufficient for their production. The traditional paradigm of differentiation towards Th1 and Th2 subtypes driven by T-bet and GATA3, respectively, has been extended to incorporate additional T cell lineages and transcriptional regulators. Technological advances have expanded our view of these lineage-specifying transcription factors to the whole genome and revealed unexpected interplay between them. From these data, it is becoming clear that lineage specification is more complex and plastic than previous models might have suggested. Here, we present an overview of the different forms of transcription factor interplay that have been identified and how T cell phenotypes arise as a product of this interplay within complex regulatory networks. We also suggest experimental strategies that will provide further insight into the mechanisms that underlie T cell lineage specification and plasticity.

  19. Globoside accelerates the differentiation of dental epithelial cells into ameloblasts

    Institute of Scientific and Technical Information of China (English)

    Takashi Nakamura; Yuta Chiba; Masahiro Naruse; Kan Saito; Hidemitsu Harada; Satoshi Fukumoto

    2016-01-01

    Tooth crown morphogenesis is tightly regulated by the proliferation and differentiation of dental epithelial cells. Globoside (Gb4), a globo-series glycosphingolipid, is highly expressed during embryogenesis as well as organogenesis, including tooth development. We previously reported that Gb4 is dominantly expressed in the neutral lipid fraction of dental epithelial cells. However, because its functional role in tooth development remains unknown, we investigated the involvement of Gb4 in dental epithelial cell differentiation. The expression of Gb4 was detected in ameloblasts of postnatal mouse molars and incisors. A cell culture analysis using HAT-7 cells, a rat-derived dental epithelial cell line, revealed that Gb4 did not promote dental epithelial cell proliferation. Interestingly, exogenous administration of Gb4 enhanced the gene expression of enamel extracellular matrix proteins such as ameloblastin, amelogenin, and enamelin in dental epithelial cells as well as in developing tooth germs. Gb4 also induced the expression of TrkB, one of the key receptors required for ameloblast induction in dental epithelial cells. In contrast, Gb4 downregulated the expression of p75, a receptor for neurotrophins (including neurotrophin-4) and a marker of undifferentiated dental epithelial cells. In addition, we found that exogenous administration of Gb4 to dental epithelial cells stimulated the extracellular signal-regulated kinase and p38 mitogen-activated protein kinase signalling pathways. Furthermore, Gb4 induced the expression of epiprofin and Runx2, the positive regulators for ameloblastin gene transcription. Thus, our results suggest that Gb4 contributes to promoting the differentiation of dental epithelial cells into ameloblasts.

  20. Correlation between membrane fluidity cellular development and stem cell differentiation

    KAUST Repository

    Noutsi, Pakiza

    2016-12-01

    Cell membranes are made up of a complex structure of lipids and proteins that diffuse laterally giving rise to what we call membrane fluidity. During cellular development, such as neuronal differentiation, cell membranes undergo dramatic structural changes induced by proteins such as ARC and Cofilin among others in the case of synaptic modification. In this study we used the generalized polarization (GP) property of fluorescent probe Laurdan using two-photon microscopy to determine membrane fluidity as a function of time and for various cell lines. A low GP value corresponds to a higher fluidity and a higher GP value is associated with a more rigid membrane. Four different cell lines were monitored such as hN2, NIH3T3, HEK293 and L6 cells. As expected, NIH3T3 cells have more rigid membrane at earlier stages of their development. On the other hand neurons tend to have the highest membrane fluidity early in their development emphasizing its correlation with plasticity and the need for this malleability during differentiation. This study sheds light on the involvement of membrane fluidity during neuronal differentiation and development of other cell lines.

  1. Cell responses to FGFR3 signalling: growth, differentiation and apoptosis

    International Nuclear Information System (INIS)

    L'Hote, Corine G.M.; Knowles, Margaret A.

    2005-01-01

    FGFR3 is a receptor tyrosine kinase (RTK) of the FGF receptor family, known to have a negative regulatory effect on long bone growth. Fgfr3 knockout mice display longer bones and, accordingly, most germline-activating mutations in man are associated with dwarfism. Somatically, some of the same activating mutations are associated with the human cancers multiple myeloma, cervical carcinoma and carcinoma of the bladder. How signalling through FGFR3 can lead to either chondrocyte apoptosis or cancer cell proliferation is not fully understood. Although FGFR3 can be expressed as two main splice isoforms (IIIb or IIIc), there is no apparent link with specific cell responses, which may rather be associated with the cell type or its differentiation status. Depending on cell type, differential activation of STAT proteins has been observed. STAT1 phosphorylation seems to be involved in inhibition of chondrocyte proliferation while activation of the ERK pathway inhibits chondrocyte differentiation and B-cell proliferation (as in multiple myeloma). The role of FGFR3 in epithelial cancers (bladder and cervix) is not known. Some of the cell specificity may arise via modulation of signalling by crosstalk with other signalling pathways. Recently, inhibition of the ERK pathway in achondroplastic mice has provided hope for an approach to the treatment of dwarfism. Further understanding of the ability of FGFR3 to trigger different responses depending on cell type and cellular context may lead to treatments for both skeletal dysplasias and cancer

  2. Optical Imaging for Stem Cell Differentiation to Neuronal Lineage

    International Nuclear Information System (INIS)

    Hwang, Do Won; Lee, Dong Soo

    2012-01-01

    In regenerative medicine, the prospect of stem cell therapy hold great promise for the recovery of injured tissues and effective treatment of intractable diseases. Tracking stem cell fate provides critical information to understand and evaluate the success of stem cell therapy. The recent emergence of in vivo noninvasive molecular imaging has enabled assessment of the behavior of grafted stem cells in living subjects. In this review, we provide an overview of current optical imaging strategies based on cell or tissue specific reporter gene expression and of in vivo methods to monitor stem cell differentiation into neuronal lineages. These methods use optical reporters either regulated by neuron-specific promoters or containing neuron-specific microRNA binding sites. Both systems revealed dramatic changes in optical reporter imaging signals in cells differentiating a yeast GAL4 amplification system or an engineering-enhanced luciferase reported gene. Furthermore, we propose an advanced imaging system to monitor neuronal differentiation during neurogenesis that uses in vivo multiplexed imaging techniques capable of detecting several targets simultaneously

  3. Colchicine affects cell motility, pattern formation and stalk cell differentiation in Dictyostelium by altering calcium signaling.

    Science.gov (United States)

    Poloz, Yekaterina; O'Day, Danton H

    2012-04-01

    Previous work, verified here, showed that colchicine affects Dictyostelium pattern formation, disrupts morphogenesis, inhibits spore differentiation and induces terminal stalk cell differentiation. Here we show that colchicine specifically induces ecmB expression and enhances accumulation of ecmB-expressing cells at the posterior end of multicellular structures. Colchicine did not induce a nuclear translocation of DimB, a DIF-1 responsive transcription factor in vitro. It also induced terminal stalk cell differentiation in a mutant strain that does not produce DIF-1 (dmtA-) and after the treatment of cells with DIF-1 synthesis inhibitor cerulenin (100 μM). This suggests that colchicine induces the differentiation of ecmB-expressing cells independent of DIF-1 production and likely through a signaling pathway that is distinct from the one that is utilized by DIF-1. Depending on concentration, colchicine enhanced random cell motility, but not chemotaxis, by 3-5 fold (10-50 mM colchicine, respectively) through a Ca(2+)-mediated signaling pathway involving phospholipase C, calmodulin and heterotrimeric G proteins. Colchicine's effects were not due to microtubule depolymerization as other microtubule-depolymerizing agents did not have these effects. Finally normal morphogenesis and stalk and spore cell differentiation of cells treated with 10 mM colchicine were rescued through chelation of Ca2+ by BAPTA-AM and EDTA and calmodulin antagonism by W-7 but not PLC inhibition by U-73122. Morphogenesis or spore cell differentiation of cells treated with 50 mM colchicine could not be rescued by the above treatments but terminal stalk cell differentiation was inhibited by BAPTA-AM, EDTA and W-7, but not U-73122. Thus colchicine disrupts morphogenesis and induces stalk cell differentiation through a Ca(2+)-mediated signaling pathway involving specific changes in gene expression and cell motility. Copyright © 2011 International Society of Differentiation. Published by Elsevier B

  4. Differentiation of a bipotential glial progenitor cell in a single cell microculture.

    Science.gov (United States)

    Temple, S; Raff, M C

    Although it is known that most cells of the vertebrate central nervous system (CNS) are derived from the neuroepithelial cells of the neural tube, the factors determining whether an individual neuroepithelial cell develops into a particular type of neurone or glial cell remain unknown. A promising model for studying this problem is the bipotential glial progenitor cell in the developing rat optic nerve; this cell differentiates into a particular type of astrocyte (a type-2 astrocyte) if cultured in 10% fetal calf serum (FCS) and into an oligodendrocyte if cultured in serum-free medium. As the oligodendrocyte-type-2 astrocyte (0-2A) progenitor cell can differentiate along either glial pathway in neurone-free cultures, living axons clearly are not required for its differentiation, at least in vitro. However, the studies on 0-2A progenitor cells were carried out in bulk cultures of optic nerve, and so it was possible that other cell-cell interactions were required for differentiation in culture. We show here that 0-2A progenitor cells can differentiate into type-2 astrocytes or oligodendrocytes when grown as isolated cells in microculture, indicating that differentiation along either glial pathway in vitro does not require signals from other CNS cells, apart from the signals provided by components of the culture medium. We also show that single 0-2A progenitor cells can differentiate along either pathway without dividing, supporting our previous studies using 3H-thymidine and suggesting that DNA replication is not required for these cells to choose between the two differentiation programmes.

  5. Smurf2 as a novel mitotic regulator: From the spindle assembly checkpoint to tumorigenesis

    Directory of Open Access Journals (Sweden)

    Moore Finola E

    2009-07-01

    Full Text Available Abstract The execution of the mitotic program with high fidelity is dependent upon precise spatiotemporal regulation of posttranslational protein modifications. For example, the timely polyubiquitination of critical mitotic regulators by Anaphase Promoting Complex/Cyclosome (APC/C is essential for the metaphase to anaphase transition and mitotic exit. The spindle assembly checkpoint prevents unscheduled activity of APC/C-Cdc20 in early mitosis, allowing bipolar attachment of kinetochores to mitotic spindle and facilitating equal segregation of sister chromatids. The critical effector of the spindle checkpoint, Mitotic arrest deficient 2 (Mad2, is recruited to unattached kinetochores forming a complex with other regulatory proteins to efficiently and cooperatively inhibit APC/C-Cdc20. A weakened and/or dysfunctional spindle checkpoint has been linked to the development of genomic instability in both cell culture and animal models, and evidence suggests that aberrant regulation of the spindle checkpoint plays a critical role in human carcinogenesis. Recent studies have illuminated a network of both degradative and non-degradative ubiquitination events that regulate the metaphase to anaphase transition and mitotic exit. Within this context, our recent work showed that the HECT (Homologous to E6-AP C-terminus-family E3 ligase Smurf2 (Smad specific ubiquitin regulatory factor 2, known as a negative regulator of transforming growth factor-beta (TGF-β signaling, is required for a functional spindle checkpoint by promoting the functional localization and stability of Mad2. Here we discuss putative models explaining the role of Smurf2 as a new regulator in the spindle checkpoint. The dynamic mitotic localization of Smurf2 to the centrosome and other critical mitotic structures provides implications about mitotic checkpoint control dependent on various ubiquitination events. Finally, deregulated Smurf2 activity may contribute to carcinogenesis by

  6. Modulation of jaw muscle spindle afferent activity following intramuscular injections with hypertonic saline.

    Science.gov (United States)

    Ro, J Y; Capra, N F

    2001-05-01

    Transient noxious chemical stimulation of small diameter muscle afferents modulates jaw movement-related responses of caudal brainstem neurons. While it is likely that the effect is mediated from the spindle afferents in the mesencephalic nucleus (Vmes) via the caudally projecting Probst's tract, the mechanisms of pain induced modulations of jaw muscle spindle afferents is not known. In the present study, we tested the hypothesis that jaw muscle nociceptors gain access to muscle spindle afferents in the same muscle via central mechanisms and alter their sensitivity. Thirty-five neurons recorded from the Vmes were characterized as muscle spindle afferents based on their responses to passive jaw movements, muscle palpation, and electrical stimulation of the masseter nerve. Each cell was tested by injecting a small volume (250 microl) of either 5% hypertonic and/or isotonic saline into the receptor-bearing muscle. Twenty-nine units were tested with 5% hypertonic saline, of which 79% (23/29) showed significant modulation of mean firing rates (MFRs) during one or more phases of ramp-and-hold movements. Among the muscle spindle primary-like units (n = 12), MFRs of 4 units were facilitated, five reduced, two showed mixed responses and one unchanged. In secondary-like units (n = 17), MFRs of 9 were facilitated, three reduced and five unchanged. Thirteen units were tested with isotonic saline, of which 77% showed no significant changes of MFRs. Further analysis revealed that the hypertonic saline not only affected the overall output of muscle spindle afferents, but also increased the variability of firing and altered the relationship between afferent signal and muscle length. These results demonstrated that activation of muscle nociceptors significantly affects proprioceptive properties of jaw muscle spindles via central neural mechanisms. The changes can have deleterious effects on oral motor function as well as kinesthetic sensibility.

  7. High levels of circulating triiodothyronine induce plasma cell differentiation.

    Science.gov (United States)

    Bloise, Flavia Fonseca; Oliveira, Felipe Leite de; Nobrega, Alberto Félix; Vasconcellos, Rita; Cordeiro, Aline; Paiva, Luciana Souza de; Taub, Dennis D; Borojevic, Radovan; Pazos-Moura, Carmen Cabanelas; Mello-Coelho, Valéria de

    2014-03-01

    The effects of hyperthyroidism on B-cell physiology are still poorly known. In this study, we evaluated the influence of high-circulating levels of 3,5,3'-triiodothyronine (T3) on bone marrow, blood, and spleen B-cell subsets, more specifically on B-cell differentiation into plasma cells, in C57BL/6 mice receiving daily injections of T3 for 14 days. As analyzed by flow cytometry, T3-treated mice exhibited increased frequencies of pre-B and immature B-cells and decreased percentages of mature B-cells in the bone marrow, accompanied by an increased frequency of blood B-cells, splenic newly formed B-cells, and total CD19(+)B-cells. T3 administration also promoted an increase in the size and cellularity of the spleen as well as in the white pulp areas of the organ, as evidenced by histological analyses. In addition, a decreased frequency of splenic B220(+) cells correlating with an increased percentage of CD138(+) plasma cells was observed in the spleen and bone marrow of T3-treated mice. Using enzyme-linked immunospot assay, an increased number of splenic immunoglobulin-secreting B-cells from T3-treated mice was detected ex vivo. Similar results were observed in mice immunized with hen egg lysozyme and aluminum adjuvant alone or together with treatment with T3. In conclusion, we provide evidence that high-circulating levels of T3 stimulate plasma cytogenesis favoring an increase in plasma cells in the bone marrow, a long-lived plasma cell survival niche. These findings indicate that a stimulatory effect on plasma cell differentiation could occur in untreated patients with Graves' disease.

  8. In vivo differentiation of induced pluripotent stem cells into neural stem cells by chimera formation.

    Science.gov (United States)

    Choi, Hyun Woo; Hong, Yean Ju; Kim, Jong Soo; Song, Hyuk; Cho, Ssang Gu; Bae, Hojae; Kim, Changsung; Byun, Sung June; Do, Jeong Tae

    2017-01-01

    Like embryonic stem cells, induced pluripotent stem cells (iPSCs) can differentiate into all three germ layers in an in vitro system. Here, we developed a new technology for obtaining neural stem cells (NSCs) from iPSCs through chimera formation, in an in vivo environment. iPSCs contributed to the neural lineage in the chimera, which could be efficiently purified and directly cultured as NSCs in vitro. The iPSC-derived, in vivo-differentiated NSCs expressed NSC markers, and their gene-expression pattern more closely resembled that of fetal brain-derived NSCs than in vitro-differentiated NSCs. This system could be applied for differentiating pluripotent stem cells into specialized cell types whose differentiation protocols are not well established.

  9. ent-Jungermannenone C Triggers Reactive Oxygen Species-Dependent Cell Differentiation in Leukemia Cells.

    Science.gov (United States)

    Yue, Zongwei; Xiao, Xinhua; Wu, Jinbao; Zhou, Xiaozhou; Liu, Weilong; Liu, Yaxi; Li, Houhua; Chen, Guoqiang; Wu, Yingli; Lei, Xiaoguang

    2018-02-23

    Acute myeloid leukemia (AML) is a hematologic malignancy that is characterized by clonal proliferation of myeloid blasts. Despite the progress that has been made in the treatment of various malignant hematopoietic diseases, the effective treatment of AML remains very challenging. Differentiation therapy has emerged as a promising approach for leukemia treatment, and new and effective chemical agents to trigger the differentiation of AML cells, especially drug-resistant cells, are urgently required. Herein, the natural product jungermannenone C, a tetracyclic diterpenoid isolated from liverworts, is reported to induce cell differentiation in AML cells. Interestingly, the unnatural enantiomer of jungermannenone C (1) was found to be more potent than jungermannenone C in inducing cell differentiation. Furthermore, compound 1 targets peroxiredoxins I and II by selectively binding to the conserved cysteine residues and leads to cellular reactive oxygen species accumulation. Accordingly, ent-jungermannenone C (1) shows potential for further investigation as an effective differentiation therapy against AML.

  10. Mesenchymal stem cell ingrowth and differentiation on coralline hydroxyapatite scaffolds

    DEFF Research Database (Denmark)

    Mygind, Tina; Stiehler, Maik; Baatrup, Anette

    2007-01-01

    Culture of osteogenic cells on a porous scaffold could offer a new solution to bone grafting using autologous human mesenchymal stem cells (hMSC) from the patient. We compared coralline hydroxyapatite scaffolds with pore sizes of 200 and 500 microm for expansion and differentiation of hMSCs. We...... polymerase chain reaction for 10 osteogenic markers. The 500-microm scaffolds had increased proliferation rates and accommodated a higher number of cells (shown by DNA content, scanning electron microscopy and fluorescence microscopy). Thus the porosity of a 3D microporous biomaterial may be used to steer h......MSC in a particular direction. We found that dynamic spinner flask cultivation of hMSC/scaffold constructs resulted in increased proliferation, differentiation and distribution of cells in scaffolds. Therefore, spinner flask cultivation is an easy-to-use inexpensive system for cultivating hMSCs on small...

  11. Decreased Intracellular pH Induced by Cariporide Differentially Contributes to Human Umbilical Cord-Derived Mesenchymal Stem Cells Differentiation

    Directory of Open Access Journals (Sweden)

    Wei Gao

    2014-01-01

    Full Text Available Background/Aims: Na+/H+ exchanger 1 (NHE1 is an important regulator of intracellular pH (pHi. High pHi is required for cell proliferation and differentiation. Our previous study has proven that the pHi of mesenchymal stem cells is higher than that of normal differentiated cells and similar to tumor cells. NHE1 is highly expressed in both mesenchymal stem cells and tumor cells. Targeted inhibition of NHE1 could induce differentiation of K562 leukemia cells. In the present paper we explored whether inhibition of NHE1 could induce differentiation of mesenchymal stem cells. Methods: MSCs were obtained from human umbilical cord and both the surface phenotype and functional characteristics were analyzed. Selective NHE1 inhibitor cariporide was used to treat human umbilical cord-derived mesenchymal stem cells (hUC-MSCs. The pHi and the differentiation of hUC-MSCs were compared upon cariporide treatment. The putative signaling pathway involved was also explored. Results: The pHi of hUC-MSCs was decreased upon cariporide treatment. Cariporide up-regulated the osteogenic differentiation of hUC-MSCs while the adipogenic differentiation was not affected. For osteogenic differentiation, β-catenin expression was up-regulated upon cariporide treatment. Conclusion: Decreased pHi induced by cariporide differentially contributes to hUC-MSCs differentiation.

  12. Local sleep spindle modulations in relation to specific memory cues

    NARCIS (Netherlands)

    Cox, R.; Hofman, W.F.; de Boer, M.; Talamini, L.M.

    2014-01-01

    Sleep spindles have been connected to memory processes in various ways. In addition, spindles appear to be modulated at the local cortical network level. We investigated whether cueing specific memories during sleep leads to localized spindle modulations in humans. During learning of word-location

  13. Arsenic inhibits hedgehog signaling during P19 cell differentiation

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Jui Tung [Environmental Toxicology Program, Clemson University, 132 Long Hall, Clemson, SC 29634 (United States); Bain, Lisa J., E-mail: lbain@clemson.edu [Environmental Toxicology Program, Clemson University, 132 Long Hall, Clemson, SC 29634 (United States); Department of Biological Sciences, Clemson University, 132 Long Hall, Clemson, SC 29634 (United States)

    2014-12-15

    Arsenic is a toxicant found in ground water around the world, and human exposure mainly comes from drinking water or from crops grown in areas containing arsenic in soils or water. Epidemiological studies have shown that arsenic exposure during development decreased intellectual function, reduced birth weight, and altered locomotor activity, while in vitro studies have shown that arsenite decreased muscle and neuronal cell differentiation. The sonic hedgehog (Shh) signaling pathway plays an important role during the differentiation of both neurons and skeletal muscle. The purpose of this study was to investigate whether arsenic can disrupt Shh signaling in P19 mouse embryonic stem cells, leading to changes muscle and neuronal cell differentiation. P19 embryonic stem cells were exposed to 0, 0.25, or 0.5 μM of sodium arsenite for up to 9 days during cell differentiation. We found that arsenite exposure significantly reduced transcript levels of genes in the Shh pathway in both a time and dose-dependent manner. This included the Shh ligand, which was decreased 2- to 3-fold, the Gli2 transcription factor, which was decreased 2- to 3-fold, and its downstream target gene Ascl1, which was decreased 5-fold. GLI2 protein levels and transcriptional activity were also reduced. However, arsenic did not alter GLI2 primary cilium accumulation or nuclear translocation. Moreover, additional extracellular SHH rescued the inhibitory effects of arsenic on cellular differentiation due to an increase in GLI binding activity. Taken together, we conclude that arsenic exposure affected Shh signaling, ultimately decreasing the expression of the Gli2 transcription factor. These results suggest a mechanism by which arsenic disrupts cell differentiation. - Highlights: • Arsenic exposure decreases sonic hedgehog pathway-related gene expression. • Arsenic decreases GLI2 protein levels and transcriptional activity in P19 cells. • Arsenic exposure does not alter the levels of SHH

  14. Nicotinamide induces differentiation of embryonic stem cells into insulin-secreting cells

    International Nuclear Information System (INIS)

    Vaca, Pilar; Berna, Genoveva; Araujo, Raquel; Carneiro, Everardo M.; Bedoya, Francisco J.; Soria, Bernat; Martin, Franz

    2008-01-01

    The poly(ADP-ribose) polymerase (PARP) inhibitor, nicotinamide, induces differentiation and maturation of fetal pancreatic cells. In addition, we have previously reported evidence that nicotinamide increases the insulin content of cells differentiated from embryonic stem (ES) cells, but the possibility of nicotinamide acting as a differentiating agent on its own has never been completely explored. Islet cell differentiation was studied by: (i) X-gal staining after neomycin selection; (ii) BrdU studies; (iii) single and double immunohistochemistry for insulin, C-peptide and Glut-2; (iv) insulin and C-peptide content and secretion assays; and (v) transplantation of differentiated cells, under the kidney capsule, into streptozotocin (STZ)-diabetic mice. Here we show that undifferentiated mouse ES cells treated with nicotinamide: (i) showed an 80% decrease in cell proliferation; (ii) co-expressed insulin, C-peptide and Glut-2; (iii) had values of insulin and C-peptide corresponding to 10% of normal mouse islets; (iv) released insulin and C-peptide in response to stimulatory glucose concentrations; and (v) after transplantation into diabetic mice, normalized blood glucose levels over 7 weeks. Our data indicate that nicotinamide decreases ES cell proliferation and induces differentiation into insulin-secreting cells. Both aspects are very important when thinking about cell therapy for the treatment of diabetes based on ES cells

  15. The Vast Universe of T Cell Diversity: Subsets of Memory Cells and Their Differentiation.

    Science.gov (United States)

    Jandus, Camilla; Usatorre, Amaia Martínez; Viganò, Selena; Zhang, Lianjun; Romero, Pedro

    2017-01-01

    The T cell receptor confers specificity for antigen recognition to T cells. By the first encounter with the cognate antigen, reactive T cells initiate a program of expansion and differentiation that will define not only the ultimate quantity of specific cells that will be generated, but more importantly their quality and functional heterogeneity. Recent achievements using mouse model infection systems have helped to shed light into the complex network of factors that dictate and sustain memory T cell differentiation, ranging from antigen load, TCR signal strength, metabolic fitness, transcriptional programs, and proliferative potential. The different models of memory T cell differentiation are discussed in this chapter, and key phenotypic and functional attributes of memory T cell subsets are presented, both for mouse and human cells. Therapeutic manipulation of memory T cell generation is expected to provide novel unique ways to optimize current immunotherapies, both in infection and cancer.

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

    Directory of Open Access Journals (Sweden)

    Emilio Satoshi Hara

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

  17. Directed Differentiation of Zebrafish Pluripotent Embryonic Cells to Functional Cardiomyocytes

    Directory of Open Access Journals (Sweden)

    Yao Xiao

    2016-09-01

    Full Text Available A cardiomyocyte differentiation in vitro system from zebrafish embryos remains to be established. Here, we have determined pluripotency window of zebrafish embryos by analyzing their gene-expression patterns of pluripotency factors together with markers of three germ layers, and have found that zebrafish undergoes a very narrow period of pluripotency maintenance from zygotic genome activation to a brief moment after oblong stage. Based on the pluripotency and a combination of appropriate conditions, we established a rapid and efficient method for cardiomyocyte generation in vitro from primary embryonic cells. The induced cardiomyocytes differentiated into functional and specific cardiomyocyte subtypes. Notably, these in vitro generated cardiomyocytes exhibited typical contractile kinetics and electrophysiological features. The system provides a new paradigm of cardiomyocyte differentiation from primary embryonic cells in zebrafish. The technology provides a new platform for the study of heart development and regeneration, in addition to drug discovery, disease modeling, and assessment of cardiotoxic agents.

  18. Effects of trichostatins on differentiation of murine erythroleukemia cells

    International Nuclear Information System (INIS)

    Yoshida, M.; Nomura, S.; Beppu, T.

    1987-01-01

    The fungistatic antibiotics trichostatins (TS) A and C were isolated from culture broth of Streptomyces platensis No. 145 and were found to be potent inducers of differentiation in murine erythroleukemia (Friend and RV133) cells at concentrations of 1.5 X 10(-8) M for TSA and 5 X 10(-7) M for TSC. Differentiation induced by TS was cooperatively enhanced by UV irradiation but not by treatment with dimethyl sulfoxide. This enhanced activity was completely inhibited by adding cycloheximide to the culture medium 2 h after exposure to TS, suggesting that TS are dimethyl sulfoxide-type inducers of erythroid differentiation. No inhibitory effect of TS was observed on macromolecular synthesis in cultured cells

  19. DIFFERENTIATION OF EMBRYONIC STEM CELLS: LESSONS FROM EMBRYONIC DEVELOPMENT

    Directory of Open Access Journals (Sweden)

    EMOKE PALL

    2008-05-01

    Full Text Available Embryonic stem (ES cells, the undifferentiated cells of early embryos are established as permanent lines and are characterised by their self-renewal capacity and the ability to retain their developmental capacity in vivo and in vitro. The pluripotent properties of ES cells are the basis of gene targeting technologies used to create mutant mouse strains with inactivated genes by homologous recombination. There are several methods to induce the formation of EBs. One of them the formation by aggregating ES cells in hanging drops, using gravity as an aggregation force. This method presents the advantage of obtaining well-calibrated EBs almost identical in size. We used at our experiment the mouse ES cell line KA1/11/C3/C8 with a normal karyotype, at 14th passages. Immunohistochemical examination was aimed to identify tissue-restricted proteins for the two differentiated lineages: titin as a cell-specific antigen for cardiac and skeletal muscle, betaIII-tubulin for the neuronal differentiation, cytokeratin Endo-A (TROMA for the presence of mesenchymal progenitor cells, Oct-4 for the presence of the undifferentiated ES cells. The beating cardiac muscle clumps showed more synchronous rhythm than those seen in EBs obtained from suspension culture method, where the beating cardiac muscle clumps appeared later, had a lower frequency and were uneven. The synaptic networks of neuronal cells were best developed in EBs from suspension, compared to those observed in EBs from hanging-drop method.

  20. Metabolism plays the key roles in Th cells differentiation

    Directory of Open Access Journals (Sweden)

    A. Hosseinzadeh

    2016-12-01

    Full Text Available The increasing rate of autoimmunity in recent decades cannot be related to only genetic instabilities and disorders. Diet can directly influence our health. Studies have shown that there is a relationship between nutritional elements and alteration in the immune system. Among immune cells, the function of T lymphocyte is important in directing immune response. T CD4+ cells lead other immune cells to respond to pathogens by secreting cytokines. HIV+ patients, who have largely lost their T CD4+ cells, are susceptible to opportunistic infections, which do not normally affect healthy people. It seems that the metabolism of T cells is critical for their differentiation and their consequent functions. After activation, T cells need to undergo clonal expansion, which is a high energy- consuming process. Studies have shown that specific metabolites deprivation or their excess supply affects T CD4+cells subsets differentiation. Abnormal induction of subsets of T CD4+ cells causes some autoimmunity reactions and hyper-sensitivity as well, which may result from imbalance of diet uptake. In this mini-review, we describe the findings about fatty acids, glucose, amino acids, and vitamins, which are effective in determining the fates of T CD4+ cells. These findings may help us uncover the role of diet in autoimmune diseases.

  1. Inorganic arsenic impairs differentiation and functions of human dendritic cells

    Energy Technology Data Exchange (ETDEWEB)

    Macoch, Mélinda; Morzadec, Claudie [UMR INSERM U1085, Institut de Recherche sur la Santé, l' Environnement et le Travail (IRSET), Université de Rennes 1, 2 avenue du Professeur Léon Bernard, 35043 Rennes (France); Fardel, Olivier [UMR INSERM U1085, Institut de Recherche sur la Santé, l' Environnement et le Travail (IRSET), Université de Rennes 1, 2 avenue du Professeur Léon Bernard, 35043 Rennes (France); Pôle Biologie, Centre Hospitalier Universitaire (CHU) Rennes, 2 rue Henri Le Guilloux, 35033 Rennes (France); Vernhet, Laurent, E-mail: laurent.vernhet@univ-rennes1.fr [UMR INSERM U1085, Institut de Recherche sur la Santé, l' Environnement et le Travail (IRSET), Université de Rennes 1, 2 avenue du Professeur Léon Bernard, 35043 Rennes (France)

    2013-01-15

    Experimental studies have demonstrated that the antileukemic trivalent inorganic arsenic prevents the development of severe pro-inflammatory diseases mediated by excessive Th1 and Th17 cell responses. Differentiation of Th1 and Th17 subsets is mainly regulated by interleukins (ILs) secreted from dendritic cells (DCs) and the ability of inorganic arsenic to impair interferon-γ and IL-17 secretion by interfering with the physiology of DCs is unknown. In the present study, we demonstrate that high concentrations of sodium arsenite (As(III), 1–2 μM) clinically achievable in plasma of arsenic-treated patients, block differentiation of human peripheral blood monocytes into immature DCs (iDCs) by inducing their necrosis. Differentiation of monocytes in the presence of non-cytotoxic concentrations of As(III) (0.1 to 0.5 μM) only slightly impacts endocytotic activity of iDCs or expression of co-stimulatory molecules in cells activated with lipopolysaccharide. However, this differentiation in the presence of As(III) strongly represses secretion of IL-12p70 and IL-23, two major regulators of Th1 and Th17 activities, from iDCs stimulated with different toll-like receptor (TLR) agonists in metalloid-free medium. Such As(III)-exposed DCs also exhibit reduced mRNA levels of IL12A and/or IL12B genes when activated with TLR agonists. Finally, differentiation of monocytes with non-cytotoxic concentrations of As(III) subsequently reduces the ability of activated DCs to stimulate the release of interferon-γ and IL-17 from Th cells. In conclusion, our results demonstrate that clinically relevant concentrations of inorganic arsenic markedly impair in vitro differentiation and functions of DCs, which may contribute to the putative beneficial effects of the metalloid towards inflammatory autoimmune diseases. Highlights: ► Inorganic arsenic impairs differentiation and functions of human dendritic cells (DCs) ► Arsenite (> 1 μM) blocks differentiation of dendritic cells by

  2. Inorganic arsenic impairs differentiation and functions of human dendritic cells

    International Nuclear Information System (INIS)

    Macoch, Mélinda; Morzadec, Claudie; Fardel, Olivier; Vernhet, Laurent

    2013-01-01

    Experimental studies have demonstrated that the antileukemic trivalent inorganic arsenic prevents the development of severe pro-inflammatory diseases mediated by excessive Th1 and Th17 cell responses. Differentiation of Th1 and Th17 subsets is mainly regulated by interleukins (ILs) secreted from dendritic cells (DCs) and the ability of inorganic arsenic to impair interferon-γ and IL-17 secretion by interfering with the physiology of DCs is unknown. In the present study, we demonstrate that high concentrations of sodium arsenite (As(III), 1–2 μM) clinically achievable in plasma of arsenic-treated patients, block differentiation of human peripheral blood monocytes into immature DCs (iDCs) by inducing their necrosis. Differentiation of monocytes in the presence of non-cytotoxic concentrations of As(III) (0.1 to 0.5 μM) only slightly impacts endocytotic activity of iDCs or expression of co-stimulatory molecules in cells activated with lipopolysaccharide. However, this differentiation in the presence of As(III) strongly represses secretion of IL-12p70 and IL-23, two major regulators of Th1 and Th17 activities, from iDCs stimulated with different toll-like receptor (TLR) agonists in metalloid-free medium. Such As(III)-exposed DCs also exhibit reduced mRNA levels of IL12A and/or IL12B genes when activated with TLR agonists. Finally, differentiation of monocytes with non-cytotoxic concentrations of As(III) subsequently reduces the ability of activated DCs to stimulate the release of interferon-γ and IL-17 from Th cells. In conclusion, our results demonstrate that clinically relevant concentrations of inorganic arsenic markedly impair in vitro differentiation and functions of DCs, which may contribute to the putative beneficial effects of the metalloid towards inflammatory autoimmune diseases. Highlights: ► Inorganic arsenic impairs differentiation and functions of human dendritic cells (DCs) ► Arsenite (> 1 μM) blocks differentiation of dendritic cells by

  3. Evaluation of a Mouse Embryonic Stem Cell Adherent Cell Differentiation and Cytotoxicity (ACDC) assay (SOT)

    Science.gov (United States)

    The Embryonic Stem Cell Test (EST) has been used to evaluate the effects of xenobiotics using three endpoints, stem cell differentiation, stem cell viability and 3T3-cell viability. Our research goal is to establish amodel system that would evaluate chemical effects using a singl...

  4. Role of Dicer1 in thyroid cell proliferation and differentiation.

    Science.gov (United States)

    Penha, Ricardo Cortez Cardoso; Sepe, Romina; De Martino, Marco; Esposito, Francesco; Pellecchia, Simona; Raia, Maddalena; Del Vecchio, Luigi; Decaussin-Petrucci, Myriam; De Vita, Gabriella; Pinto, Luis Felipe Ribeiro; Fusco, Alfredo

    2017-01-01

    DICER1 plays a central role in the biogenesis of microRNAs and it is important for normal development. Altered microRNA expression and DICER1 dysregulation have been described in several types of tumors, including thyroid carcinomas. Recently, our group identified a new somatic mutation (c.5438A>G; E1813G) within DICER1 gene of an unknown function. Herein, we show that DICER1 is overexpressed, at mRNA level, in a significant-relative number of papillary (70%) and anaplastic (42%) thyroid carcinoma samples, whereas is drastically downregulated in all the analyzed human thyroid carcinoma cell lines (TPC-1, BCPAP, FRO and 8505c) in comparison with normal thyroid tissue samples. Conversely, DICER1 is downregulated, at protein level, in PTC in comparison with normal thyroid tissues. Our data also reveals that DICER1 overexpression positively regulates thyroid cell proliferation, whereas its silencing impairs thyroid cell differentiation. The expression of DICER1 gene mutation (c.5438A>G; E1813G) negatively affects the microRNA machinery and cell proliferation as well as upregulates DICER1 protein levels of thyroid cells but has no impact on thyroid differentiation. In conclusion, DICER1 protein is downregulated in papillary thyroid carcinomas and affects thyroid proliferation and differentiation, while DICER1 gene mutation (c.5438A>G; E1813G) compromises the DICER1 wild-type-mediated microRNA processing and cell proliferation.

  5. EZH2: a pivotal regulator in controlling cell differentiation.

    Science.gov (United States)

    Chen, Ya-Huey; Hung, Mien-Chie; Li, Long-Yuan

    2012-01-01

    Epigenetic regulation plays an important role in stem cell self-renewal, maintenance and lineage differentiation. The epigenetic profiles of stem cells are related to their transcriptional signature. Enhancer of Zeste homlog 2 (EZH2), a catalytic subunit of epigenetic regulator Polycomb repressive complex 2 (PRC2), has been shown to be a key regulator in controlling cellular differentiation. EZH2 is a histone methyltransferase that not only methylates histone H3 on Lys 27 (H3K27me3) but also interacts with and recruits DNA methyltransferases to methylate CpG at certain EZH2 target genes to establish firm repressive chromatin structures, contributing to tumor progression and the regulation of development and lineage commitment both in embryonic stem cells (ESCs) and adult stem cells. In addition to its well-recognized epigenetic gene silencing function, EZH2 also directly methylates nonhistone targets such as the cardiac transcription factor, GATA4, resulting in attenuated GATA4 transcriptional activity and gene repression. This review addresses recent progress toward the understanding of the biological functions and regulatory mechanisms of EZH2 and its targets as well as their roles in stem cell maintenance and cell differentiation.

  6. Glucose metabolism regulates T cell activation, differentiation and functions

    Directory of Open Access Journals (Sweden)

    Clovis Steve Palmer

    2015-01-01

    Full Text Available The adaptive immune system is equipped to eliminate both tumors and pathogenic microorganisms. It requires a series of complex and coordinated signals to drive the activation, proliferation and differentiation of appropriate T cell subsets. It is now established that changes in cellular activation are coupled to profound changes in cellular metabolism. In addition, emerging evidence now suggest that specific metabolic alterations associated with distinct T cell subsets may be ancillary to their differentiation and influential in their immune functions. The Warburg effect originally used to describe a phenomenon in which most cancer cells relied on aerobic glycolysis for their growth is a key process that sustain T cell activation and differentiation. Here we review how different aspects of metabolism in T cells influence their functions, focusing on the emerging role of key regulators of glucose metabolism such as HIF-1α. A thorough understanding of the role of metabolism in T cell function could provide insights into mechanisms involved in inflammatory-mediated conditions, with the potential for developing novel therapeutic approaches to treat these diseases.

  7. Vinpocetine Attenuates the Osteoblastic Differentiation of Vascular Smooth Muscle Cells.

    Directory of Open Access Journals (Sweden)

    Yun-Yun Ma

    Full Text Available Vascular calcification is an active process of osteoblastic differentiation of vascular smooth muscle cells; however, its definite mechanism remains unknown. Vinpocetine, a derivative of the alkaloid vincamine, has been demonstrated to inhibit the high glucose-induced proliferation of vascular smooth muscle cells; however, it remains unknown whether vinpocetine can affect the osteoblastic differentiation of vascular smooth muscle cells. We hereby investigated the effect of vinpocetine on vascular calcification using a beta-glycerophosphate-induced cell model. Our results showed that vinpocetine significantly reduced the osteoblast-like phenotypes of vascular smooth muscle cells including ALP activity, osteocalcin, collagen type I, Runx2 and BMP-2 expression as well as the formation of mineralized nodule. Vinpocetine, binding to translocation protein, induced phosphorylation of extracellular signal-related kinase and Akt and thus inhibited the translocation of nuclear factor-kappa B into the nucleus. Silencing of translocator protein significantly attenuated the inhibitory effect of vinpocetine on osteoblastic differentiation of vascular smooth muscle cells. Taken together, vinpocetine may be a promising candidate for the clinical therapy of vascular calcification.

  8. Planar Cell Polarity Controls Pancreatic Beta Cell Differentiation and Glucose Homeostasis

    DEFF Research Database (Denmark)

    Cortijo, Cedric; Gouzi, Mathieu; Tissir, Fadel

    2012-01-01

    glucose clearance. Loss of Celsr2 and 3 leads to a reduction of Jun phosphorylation in progenitors, which, in turn, reduces beta cell differentiation from endocrine progenitors. These results highlight the importance of the PCP pathway in cell differentiation in vertebrates. In addition, they reveal.......5 synchronously to apicobasal polarization of pancreas progenitors. Loss of function of the two PCP core components Celsr2 and Celsr3 shows that they control the differentiation of endocrine cells from polarized progenitors, with a prevalent effect on insulin-producing beta cells. This results in a decreased...

  9. Induction of early differentiation as a means of cell sterilization

    International Nuclear Information System (INIS)

    Wangenheim, K.-H. v.

    1979-01-01

    Investigations in plants suggest that cytoplasmic growth during mitotic delay induces an early attainment of terminal differentiation and cessation of mitotic activity. In mammals a direct demonstration of these processes is difficult. Plants and mammals show, however, a common phenomenon: Polyploidy does not usually reduce radiosensitivity as drastically as predicted by genetical considerations and certain experimental results. In root meristems of barley it is shown that cytoplasmic growth during mitotic delay increases the amount of cytoplasma per nuclear genome to approximately the same levels in tetraploid as in diploid cells. This results in the same loss, for both ploidy levels, of meristematic cells due to early differentiation. Apparently, under usual conditions, polyploidy is unable to significantly reduce radiosensitivity because the induction of differentiation processes is more important to radiation damage than the direct effect of genetic damage. Since the same basic principles also occur in mammals, it is suggested that early differentiation, and thereby cell sterilization, are induced in mammalian cells by the same mechanism as in plants. (Auth.)

  10. Protein signaling pathways in differentiation of neural stem cells

    Czech Academy of Sciences Publication Activity Database

    Skalníková, Helena; Vodička, Petr; Pelech, S.; Motlík, Jan; Gadher, S. J.; Kovářová, Hana

    2008-01-01

    Roč. 8, - (2008), s. 4547-4559 ISSN 1615-9853 R&D Projects: GA MŠk 1M0538 Institutional research plan: CEZ:AV0Z50450515 Keywords : antibody microarray * differentiation * neural stem cells Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 4.586, year: 2008

  11. 21 CFR 864.5220 - Automated differential cell counter.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Automated differential cell counter. 864.5220 Section 864.5220 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Automated and Semi-Automated Hematology Devices...

  12. Calorie Restriction Attenuates Terminal Differentiation of Immune Cells.

    Science.gov (United States)

    White, Matthew J; Beaver, Charlotte M; Goodier, Martin R; Bottomley, Christian; Nielsen, Carolyn M; Wolf, Asia-Sophia F M; Boldrin, Luisa; Whitmore, Charlotte; Morgan, Jennifer; Pearce, Daniel J; Riley, Eleanor M

    2016-01-01

    Immune senescence is a natural consequence of aging and may contribute to frailty and loss of homeostasis in later life. Calorie restriction increases healthy life-span in C57BL/6J (but not DBA/2J) mice, but whether this is related to preservation of immune function, and how it interacts with aging, is unclear. We compared phenotypic and functional characteristics of natural killer (NK) cells and T cells, across the lifespan, of calorie-restricted (CR) and control C57BL/6 and DBA/2 mice. Calorie restriction preserves a naïve T cell phenotype and an immature NK cell phenotype as mice age. The splenic T cell populations of CR mice had higher proportions of CD11a - CD44 lo cells, lower expression of TRAIL, KLRG1, and CXCR3, and higher expression of CD127, compared to control mice. Similarly, splenic NK cells from CR mice had higher proportions of less differentiated CD11b - CD27 + cells and correspondingly lower proportions of highly differentiated CD11b + CD27 - NK cells. Within each of these subsets, cells from CR mice had higher expression of CD127, CD25, TRAIL, NKG2A/C/E, and CXCR3 and lower expression of KLRG1 and Ly49 receptors compared to controls. The effects of calorie restriction on lymphoid cell populations in lung, liver, and lymph nodes were identical to those seen in the spleen, indicating that this is a system-wide effect. The impact of calorie restriction on NK cell and T cell maturation is much more profound than the effect of aging and, indeed, calorie restriction attenuates these age-associated changes. Importantly, the effects of calorie restriction on lymphocyte maturation were more marked in C57BL/6 than in DBA/2J mice indicating that delayed lymphocyte maturation correlates with extended lifespan. These findings have implications for understanding the interaction between nutritional status, immunity, and healthy lifespan in aging populations.

  13. Effect of silver nanoparticles on human mesenchymal stem cell differentiation

    Directory of Open Access Journals (Sweden)

    Christina Sengstock

    2014-11-01

    Full Text Available Background: Silver nanoparticles (Ag-NP are one of the fastest growing products in nano-medicine due to their enhanced antibacterial activity at the nanoscale level. In biomedicine, hundreds of products have been coated with Ag-NP. For example, various medical devices include silver, such as surgical instruments, bone implants and wound dressings. After the degradation of these materials, or depending on the coating technique, silver in nanoparticle or ion form can be released and may come into close contact with tissues and cells. Despite incorporation of Ag-NP as an antibacterial agent in different products, the toxicological and biological effects of silver in the human body after long-term and low-concentration exposure are not well understood. In the current study, we investigated the effects of both ionic and nanoparticulate silver on the differentiation of human mesenchymal stem cells (hMSCs into adipogenic, osteogenic and chondrogenic lineages and on the secretion of the respective differentiation markers adiponectin, osteocalcin and aggrecan.Results: As shown through laser scanning microscopy, Ag-NP with a size of 80 nm (hydrodynamic diameter were taken up into hMSCs as nanoparticulate material. After 24 h of incubation, these Ag-NP were mainly found in the endo-lysosomal cell compartment as agglomerated material. Cytotoxicity was observed for differentiated or undifferentiated hMSCs treated with high silver concentrations (≥20 µg·mL−1 Ag-NP; ≥1.5 µg·mL−1 Ag+ ions but not with low-concentration treatments (≤10 µg·mL−1 Ag-NP; ≤1.0 µg·mL−1 Ag+ ions. Subtoxic concentrations of Ag-NP and Ag+ ions impaired the adipogenic and osteogenic differentiation of hMSCs in a concentration-dependent manner, whereas chondrogenic differentiation was unaffected after 21 d of incubation. In contrast to aggrecan, the inhibitory effect of adipogenic and osteogenic differentiation was confirmed by a decrease in the secretion of

  14. Direct kinetochore–spindle pole connections are not required for chromosome segregation

    Science.gov (United States)

    Sikirzhytski, Vitali; Magidson, Valentin; Steinman, Jonathan B.; He, Jie; Le Berre, Maël; Tikhonenko, Irina; Ault, Jeffrey G.; McEwen, Bruce F.; Chen, James K.; Sui, Haixin; Piel, Matthieu; Kapoor, Tarun M.

    2014-01-01

    Segregation of genetic material occurs when chromosomes move to opposite spindle poles during mitosis. This movement depends on K-fibers, specialized microtubule (MT) bundles attached to the chromosomes′ kinetochores. A long-standing assumption is that continuous K-fibers connect every kinetochore to a spindle pole and the force for chromosome movement is produced at the kinetochore and coupled with MT depolymerization. However, we found that chromosomes still maintained their position at the spindle equator during metaphase and segregated properly during anaphase when one of their K-fibers was severed near the kinetochore with a laser microbeam. We also found that, in normal fully assembled spindles, K-fibers of some chromosomes did not extend to the spindle pole. These K-fibers connected to adjacent K-fibers and/or nonkinetochore MTs. Poleward movement of chromosomes with short K-fibers was uncoupled from MT depolymerization at the kinetochore. Instead, these chromosomes moved by dynein-mediated transport of the entire K-fiber/kinetochore assembly. Thus, at least two distinct parallel mechanisms drive chromosome segregation in mammalian cells. PMID:25023516

  15. Direct kinetochore-spindle pole connections are not required for chromosome segregation.

    Science.gov (United States)

    Sikirzhytski, Vitali; Magidson, Valentin; Steinman, Jonathan B; He, Jie; Le Berre, Maël; Tikhonenko, Irina; Ault, Jeffrey G; McEwen, Bruce F; Chen, James K; Sui, Haixin; Piel, Matthieu; Kapoor, Tarun M; Khodjakov, Alexey

    2014-07-21

    Segregation of genetic material occurs when chromosomes move to opposite spindle poles during mitosis. This movement depends on K-fibers, specialized microtubule (MT) bundles attached to the chromosomes' kinetochores. A long-standing assumption is that continuous K-fibers connect every kinetochore to a spindle pole and the force for chromosome movement is produced at the kinetochore and coupled with MT depolymerization. However, we found that chromosomes still maintained their position at the spindle equator during metaphase and segregated properly during anaphase when one of their K-fibers was severed near the kinetochore with a laser microbeam. We also found that, in normal fully assembled spindles, K-fibers of some chromosomes did not extend to the spindle pole. These K-fibers connected to adjacent K-fibers and/or nonkinetochore MTs. Poleward movement of chromosomes with short K-fibers was uncoupled from MT depolymerization at the kinetochore. Instead, these chromosomes moved by dynein-mediated transport of the entire K-fiber/kinetochore assembly. Thus, at least two distinct parallel mechanisms drive chromosome segregation in mammalian cells.

  16. Chemo-mechanical control of neural stem cell differentiation

    Science.gov (United States)

    Geishecker, Emily R.

    Cellular processes such as adhesion, proliferation, and differentiation are controlled in part by cell interactions with the microenvironment. Cells can sense and respond to a variety of stimuli, including soluble and insoluble factors (such as proteins and small molecules) and externally applied mechanical stresses. Mechanical properties of the environment, such as substrate stiffness, have also been suggested to play an important role in cell processes. The roles of both biochemical and mechanical signaling in fate modification of stem cells have been explored independently. However, very few studies have been performed to study well-controlled chemo-mechanotransduction. The objective of this work is to design, synthesize, and characterize a chemo-mechanical substrate to encourage neuronal differentiation of C17.2 neural stem cells. In Chapter 2, Polyacrylamide (PA) gels of varying stiffnesses are functionalized with differing amounts of whole collagen to investigate the role of protein concentration in combination with substrate stiffness. As expected, neurons on the softest substrate were more in number and neuronal morphology than those on stiffer substrates. Neurons appeared locally aligned with an expansive network of neurites. Additional experiments would allow for statistical analysis to determine if and how collagen density impacts C17.2 differentiation in combination with substrate stiffness. Due to difficulties associated with whole protein approaches, a similar platform was developed using mixed adhesive peptides, derived from fibronectin and laminin, and is presented in Chapter 3. The matrix elasticity and peptide concentration can be individually modulated to systematically probe the effects of chemo-mechanical signaling on differentiation of C17.2 cells. Polyacrylamide gel stiffness was confirmed using rheological techniques and found to support values published by Yeung et al. [1]. Cellular growth and differentiation were assessed by cell counts

  17. Dissecting stem cell differentiation using single cell expression profiling

    OpenAIRE

    Moignard, Victoria Rachel; Göttgens, Berthold

    2016-01-01

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

  18. Roquin Paralogs Differentially Regulate Functional NKT Cell Subsets.

    Science.gov (United States)

    Drees, Christoph; Vahl, J Christoph; Bortoluzzi, Sabrina; Heger, Klaus D; Fischer, Julius C; Wunderlich, F Thomas; Peschel, Christian; Schmidt-Supprian, Marc

    2017-04-01

    NKT cells represent a small subset of glycolipid-recognizing T cells that are heavily implicated in human allergic, autoimmune, and malignant diseases. In the thymus, precursor cells recognize self-glycolipids by virtue of their semi-invariant TCR, which triggers NKT cell lineage commitment and maturation. During their development, NKT cells are polarized into the NKT1, NKT2, and NKT17 subsets, defined through their cytokine-secretion patterns and the expression of key transcription factors. However, we have largely ignored how the differentiation into the NKT cell subsets is regulated. In this article, we describe the mRNA-binding Roquin-1 and -2 proteins as central regulators of murine NKT cell fate decisions. In the thymus, T cell-specific ablation of the Roquin paralogs leads to a dramatic expansion of NKT17 cells, whereas peripheral mature NKT cells are essentially absent. Roquin-1/2-deficient NKT17 cells show exaggerated lineage-specific expression of nearly all NKT17-defining proteins tested. We show through mixed bone marrow chimera experiments that NKT17 polarization is mediated through cell-intrinsic mechanisms early during NKT cell development. In contrast, the loss of peripheral NKT cells is due to cell-extrinsic factors. Surprisingly, Roquin paralog-deficient NKT cells are, in striking contrast to conventional T cells, compromised in their ability to secrete cytokines. Altogether, we show that Roquin paralogs regulate the development and function of NKT cell subsets in the thymus and periphery. Copyright © 2017 by The American Association of Immunologists, Inc.

  19. Differentiation of bovine spermatogonial stem cells into osteoblasts.

    Science.gov (United States)

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

    2011-07-01

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

  20. Evidence for differentiation of cell wall poles in Bacillus subtilis

    International Nuclear Information System (INIS)

    Sonnenfeld, E.M.

    1985-01-01

    Previous data have suggested that the chromosome of Bacillus subtilis was found to the cell surface at polar regions. A significant corollary of DNA attachment to cell poles is the role of the cell wall in chromosome segregation. This project was mainly concerned with visualizing the DNA-cell wall association through autoradiography. The origin and terminus of replication were labelled with ( 3 H)-thymidine using a temperature-sensitive DNA initiation mutant. It was found that most of the radioactivity was associated with cell poles. Ultrastructural analyses of cell walls stained with dilute cationized ferritin showed that the polar area contained a site of dense electronegativity. It is not immediately apparent why cell wall poles would contain an area with a high concentration of negative charge. This finding may be related to the cell pole functioning as the site of chromosome attachment. An additional observation encountered in this study was that cell wall exhibited asymmetry with regard to negative charge, the outside surface being more electronegative than the inside. A significant consequence of this finding is that both teichoic acid and muramyl peptides are situated perpendicularly to the cell surface. This favored arrangement may facilitate cell separation during the division process due to opposition of like charges at septa. The results of this work provide further convincing evidence that the cell wall of B. subtilis is differentiated

  1. Differentiation of isolated human umbilical cord mesenchymal stem cells into neural stem cells

    Science.gov (United States)

    Chen, Song; Zhang, Wei; Wang, Ji-Ming; Duan, Hong-Tao; Kong, Jia-Hui; Wang, Yue-Xin; Dong, Meng; Bi, Xue; Song, Jian

    2016-01-01

    AIM To investigate whether umbilical cord human mesenchymal stem cell (UC-MSC) was able to differentiate into neural stem cell and neuron in vitro. METHODS The umbilical cords were obtained from pregnant women with their written consent and the approval of the Clinic Ethnics Committee. UC-MSC were isolated by adherent culture in the medium contains 20% fetal bovine serum (FBS), then they were maintained in the medium contain 10% FBS and induced to neural cells in neural differentiation medium. We investigated whether UC-MSC was able to differentiate into neural stem cell and neuron in vitro by using flow cytometry, reverse transcriptase-polymerase chain reaction (RT-PCR) and immunofluorescence (IF) analyzes. RESULTS A substantial number of UC-MSC was harvested using the tissue explants adherent method at about 2wk. Flow cytometric study revealed that these cells expressed common markers of MSCs, such as CD105 (SH2), CD73 (SH3) and CD90. After induction of differentiation of neural stem cells, the cells began to form clusters; RT-PCR and IF showed that the neuron specific enolase (NSE) and neurogenic differentiation 1-positive cells reached 87.3%±14.7% and 72.6%±11.8%, respectively. Cells showed neuronal cell differentiation after induced, including neuron-like protrusions, plump cell body, obviously and stronger refraction. RT-PCR and IF analysis showed that microtubule-associated protein 2 (MAP2) and nuclear factor-M-positive cells reached 43.1%±10.3% and 69.4%±19.5%, respectively. CONCLUSION Human umbilical cord derived MSCs can be cultured and proliferated in vitro and differentiate into neural stem cells, which may be a valuable source for cell therapy of neurodegenerative eye diseases. PMID:26949608

  2. Differentiation of isolated human umbilical cord mesenchymal stem cells into neural stem cells

    Directory of Open Access Journals (Sweden)

    Song Chen

    2016-01-01

    Full Text Available AIM: To investigate whether umbilical cord human mesenchymal stem cell (UC-MSC was able to differentiate into neural stem cell and neuron in vitro. METHODS: The umbilical cords were obtained from pregnant women with their written consent and the approval of the Clinic Ethnics Committee. UC-MSC were isolated by adherent culture in the medium contains 20% fetal bovine serum (FBS, then they were maintained in the medium contain 10% FBS and induced to neural cells in neural differentiation medium. We investigated whether UC-MSC was able to differentiate into neural stem cell and neuron in vitro by using flow cytometry, reverse transcriptase-polymerase chain reaction (RT-PCR and immunofluorescence (IF analyzes. RESULTS: A substantial number of UC-MSC was harvested using the tissue explants adherent method at about 2wk. Flow cytometric study revealed that these cells expressed common markers of MSCs, such as CD105 (SH2, CD73 (SH3 and CD90. After induction of differentiation of neural stem cells, the cells began to form clusters; RT-PCR and IF showed that the neuron specific enolase (NSE and neurogenic differentiation 1-positive cells reached 87.3%±14.7% and 72.6%±11.8%, respectively. Cells showed neuronal cell differentiation after induced, including neuron-like protrusions, plump cell body, obviously and stronger refraction. RT-PCR and IF analysis showed that microtubule-associated protein 2 (MAP2 and nuclear factor-M-positive cells reached 43.1%±10.3% and 69.4%±19.5%, respectively. CONCLUSION: Human umbilical cord derived MSCs can be cultured and proliferated in vitro and differentiate into neural stem cells, which may be a valuable source for cell therapy of neurodegenerative eye diseases.

  3. The effect of dexamethasone and triiodothyronine on terminal differentiation of primary bovine chondrocytes and chondrogenically differentiated mesenchymal stem cells.

    Science.gov (United States)

    Randau, Thomas M; Schildberg, Frank A; Alini, Mauro; Wimmer, Matthias D; Haddouti, El-Mustapha; Gravius, Sascha; Ito, Keita; Stoddart, Martin J

    2013-01-01

    The newly evolved field of regenerative medicine is offering solutions in the treatment of bone or cartilage loss and deficiency. Mesenchymal stem cells, as well as articular chondrocytes, are potential cells for the generation of bone or cartilage. The natural mechanism of bone formation is that of endochondral ossification, regulated, among other factors, through the hormones dexamethasone and triiodothyronine. We investigated the effects of these hormones on articular chondrocytes and chondrogenically differentiated mesenchymal stem cells, hypothesizing that these hormones would induce terminal differentiation, with chondrocytes and differentiated stem cells being similar in their response. Using a 3D-alginate cell culture model, bovine chondrocytes and chondrogenically differentiated stem cells were cultured in presence of triiodothyronine or dexamethasone, and cell proliferation and extracellular matrix production were investigated. Collagen mRNA expression was measured by real-time PCR. Col X mRNA and alkaline phosphatase were monitored as markers of terminal differentiation, a prerequisite of endochondral ossification. The alginate culture system worked well, both for the culture of chondrocytes and for the chondrogenic differentiation of mesenchymal stem cells. Dexamethasone led to an increase in glycosaminoglycan production. Triiodothyronine increased the total collagen production only in chondrocytes, where it also induced signs of terminal differentiation, increasing both collagen X mRNA and alkaline phosphatase activity. Dexamethasone induced terminal differentiation in the differentiated stem cells. The immature articular chondrocytes used in this study seem to be able to undergo terminal differentiation, pointing to their possible role in the onset of degenerative osteoarthritis, as well as their potential for a cell source in bone tissue engineering. When chondrocyte-like cells, after their differentiation, can indeed be moved on towards terminal

  4. PU.1 silencing leads to terminal differentiation of erythroleukemia cells

    International Nuclear Information System (INIS)

    Atar, Orna; Levi, Ben-Zion

    2005-01-01

    The transcription factor PU.1 plays a central role in development and differentiation of hematopoietic cells. Evidence from PU.1 knockout mice indicates a pivotal role for PU.1 in myeloid lineage and B-lymphocyte development. In addition, PU.1 is a key player in the development of Friend erythroleukemia disease, which is characterized by proliferation and differentiation arrest of proerythrocytes. To study the role of PU.1 in erythroleukemia, we have used murine erythroleukemia cells, isolated from Friend virus-infected mice. Expression of PU.1 small interfering RNA in these cells led to significant inhibition of PU.1 levels. This was accompanied by inhibition of proliferation and restoration in the ability of the proerythroblastic cells to produce hemoglobin, i.e., reversion of the leukemic phenotype. The data suggest that overexpression of PU.1 gene is the immediate cause for maintaining the leukemic phenotype of the disease by retaining the self-renewal capacity of transformed erythroblastic cells and by blocking the terminal differentiation program towards erythrocytes

  5. The role of p53 in the response to mitotic spindle damage

    International Nuclear Information System (INIS)

    Meek, D.W.

    2000-01-01

    The p53 tumour suppressor protein has defined roles in G1/S and G2/M cell cycle checkpoint in response to a range of cellular stresses including DNA damage, dominant oncogene expression, hypoxia, metabolic changes and viral infection. In addition to these responses, p53 can also be activated when damage occurs to the mitotic spindle. Initially, spindle damage activates a p53-independent checkpoint which functions at the metaphase-anaphase transition and prevents cells from progressing through mitosis until the completion of spindle formation. Cells eventually escape from this block (a process termed 'mitotic slippage'), and an aberrant mitosis ensues in which sister chromatids fail to segregate properly. After a delay period, p53 responds to this mitotic failure by instituting a G1-like growth arrest, with an intact nucleus containing 4N DNA, but without the cells undergoing division. Cells lacking wild-type p53 are still able to arrest transiently at mitosis, and also fail to undergo division, underscoring that the delay in mitosis is p53-independent. However, these cells are not prevented from re-entering the cell cycle and can reduplicate their DNA unchecked, leading to polyploidy. Additionally, p53-null cells which experience spindle failure often show the appearance of micronuclei arising from poorly segregated chromosomes which have de-condensed and been enclosed in a nuclear envelope. The ability of p53 to prevent their formation suggests an additional G2 involvement which prevents nuclear breakdown prior to mitosis. The molecular mechanism by which p53 is able to sense mitotic failure is still unknown, but may be linked to the ability of p53 to regulate duplication of the centrosome, the organelle which nucleates spindle formation. (authors)

  6. The differentiation potential of adipose tissue-derived mesenchymal stem cells into cell lineage related to male germ cells

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    P. Bräunig

    Full Text Available ABSTRACT The adipose tissue is a reliable source of Mesenchymal stem cells (MSCs showing a higher plasticity and transdifferentiation potential into multilineage cells. In the present study, adipose tissue-derived mesenchymal stem cells (AT-MSCs were isolated from mice omentum and epididymis fat depots. The AT-MSCs were initially compared based on stem cell surface markers and on the mesodermal trilineage differentiation potential. Additionally, AT-MSCs, from both sources, were cultured with differentiation media containing retinoic acid (RA and/or testicular cell-conditioned medium (TCC. The AT-MSCs expressed mesenchymal surface markers and differentiated into adipogenic, chondrogenic and osteogenic lineages. Only omentum-derived AT-MSCs expressed one important gene marker related to male germ cell lineages, after the differentiation treatment with RA. These findings reaffirm the importance of adipose tissue as a source of multipotent stromal-stem cells, as well as, MSCs source regarding differentiation purpose.

  7. Bee venom enhances the differentiation of human regulatory T cells.

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    Caramalho, I; Melo, A; Pedro, E; Barbosa, M M P; Victorino, R M M; Pereira Santos, M C; Sousa, A E

    2015-10-01

    Venom-specific immunotherapy (VIT) is well recognized by its efficacy, and compelling evidence implicates regulatory T cells (Tregs) in the underlying tolerogenic mechanisms. Additionally, hymenoptera venom has for a long time been claimed to modulate immunity. Here, we investigated the putative role of bee venom (Bv) in human FOXP3-expressing Treg homeostasis and differentiation, irrespective of the donors' allergic status. We found that Bv significantly enhanced the differentiation of FOXP3-expressing cells both from conventional naïve CD4 T cells and mature CD4 thymocytes, a property that may contribute to the VIT's capacity to expand circulating Tregs in allergic individuals. We expect that our data enlightening the Treg-mediated immunomodulatory properties of Bv regardless of TCR specificity, to have application in other allergies, as well as in other clinical settings, such as autoimmunity and transplantation. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  8. Acridones as inducers of HL-60 cell differentiation.

    Science.gov (United States)

    Kawaii, S; Tomono, Y; Katase, E; Ogawa, K; Yano, M; Takemura, Y; Ju-ichi, M; Ito, C; Furukawa, H

    1999-03-01

    Fifteen acridone alkaloids were examined for their activity of induction of human promyelocytic leukemia cell (HL-60) differentiation. HL-60 cells were differentiated into mature monocyte/macrophage by atalaphyllidine (9), atalaphyllinine (12), and des-N-methylnoracronycine (13). The activities of NBT reduction, nonspecific esterase, and phagocytosis, were induced by 2.5 microM of 9, 12, and 13. After a 4-day treatment, 9, 12, and 13 at 10 microM inhibited clonal proliferation of HL-60 cells by 28, 96, and 63%, respectively. The structure-activity relationship established from the results revealed that hydroxyl group at C-1 and prenyl group at C-2 had an important role.

  9. Assessing T cell differentiation at the single-cell level

    NARCIS (Netherlands)

    Gerlach, Carmen

    2012-01-01

    This thesis describes the development and use of a novel technology for single-cell fate mapping, called cellular barcoding. With this technology, unique and heritable genetic tags (barcodes) are introduced into naïve T cells. Using cellular barcoding, we investigated I) how different

  10. Efficient Differentiation of Mouse Embryonic Stem Cells into Insulin-Producing Cells

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    Szu-Hsiu Liu

    2012-01-01

    Full Text Available Embryonic stem (ES cells are a potential source of a variety of differentiated cells for cell therapy, drug discovery, and toxicology screening. Here, we present an efficacy strategy for the differentiation of mouse ES cells into insulin-producing cells (IPCs by a two-step differentiation protocol comprising of (i the formation of definitive endoderm in monolayer culture by activin A, and (ii this monolayer endoderm being induced to differentiate into IPCs by nicotinamide, insulin, and laminin. Differentiated cells can be obtained within approximately 7 days. The differentiation IPCs combined application of RT-PCR, ELISA, and immunofluorescence to characterize phenotypic and functional properties. In our study, we demonstrated that IPCs produced pancreatic transcription factors, endocrine progenitor marker, definitive endoderm, pancreatic β-cell markers, and Langerhans α and δ cells. The IPCs released insulin in a manner that was dose dependent upon the amount of glucose added. These techniques may be able to be applied to human ES cells, which would have very important ramifications for treating human disease.

  11. Identifying States along the Hematopoietic Stem Cell Differentiation Hierarchy with Single Cell Specificity via Raman Spectroscopy.

    Science.gov (United States)

    Ilin, Yelena; Choi, Ji Sun; Harley, Brendan A C; Kraft, Mary L

    2015-11-17

    A major challenge for expanding specific types of hematopoietic cells ex vivo for the treatment of blood cell pathologies is identifying the combinations of cellular and matrix cues that direct hematopoietic stem cells (HSC) to self-renew or differentiate into cell populations ex vivo. Microscale screening platforms enable minimizing the number of rare HSCs required to screen the effects of numerous cues on HSC fate decisions. These platforms create a strong demand for label-free methods that accurately identify the fate decisions of individual hematopoietic cells at specific locations on the platform. We demonstrate the capacity to identify discrete cells along the HSC differentiation hierarchy via multivariate analysis of Raman spectra. Notably, cell state identification is accurate for individual cells and independent of the biophysical properties of the functionalized polyacrylamide gels upon which these cells are cultured. We report partial least-squares discriminant analysis (PLS-DA) models of single cell Raman spectra enable identifying four dissimilar hematopoietic cell populations across the HSC lineage specification. Successful discrimination was obtained for a population enriched for long-term repopulating HSCs (LT-HSCs) versus their more differentiated progeny, including closely related short-term repopulating HSCs (ST-HSCs) and fully differentiated lymphoid (B cells) and myeloid (granulocytes) cells. The lineage-specific differentiation states of cells from these four subpopulations were accurately identified independent of the stiffness of the underlying biomaterial substrate, indicating subtle spectral variations that discriminated these populations were not masked by features from the culture substrate. This approach enables identifying the lineage-specific differentiation stages of hematopoietic cells on biomaterial substrates of differing composition and may facilitate correlating hematopoietic cell fate decisions with the extrinsic cues that

  12. Spindle-cell carcinoma of the prostate

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    Carlos Hirokatsu Watanabe Silva

    2012-03-01

    Full Text Available Sarcoma of the prostate and sarcomatoid carcinoma of the prostate are rareconditions, both characterized by a poor prognosis. Sarcomatoid carcinoma ofthe prostate typically arises from the evolution of an underlying adenocarcinoma,occasionally featuring heterologous elements, bulky disease being possiblebut rare. In contrast, sarcoma of the prostate derives from non-epithelialmesenchymal components of the prostatic stroma, shows rapid growth, andfrequently presents as massive pelvic tumors obstructing the urinary tractat the time of diagnosis. We report the case of a 55-year-old patient with atwo-month history of symptoms of urinary obstruction. The patient presentedwith an extremely enlarged heterogeneous prostate, although his prostatespecificantigen level was low. The lack of a history of prostatic neoplasia ledus to suspect sarcoma, and a transrectal prostate biopsy was carried out. Animmunohistochemical study of the biopsy specimen did not confirm the clinicalsuspicion. However, in view of the clinical features, we believe that sarcoma ofthe prostate was the most likely diagnosis. The patient received neoadjuvantchemotherapy followed by radiation therapy. At this writing, surgical resectionhad yet to be scheduled.

  13. Poorly Differentiated Squamous Cell Carcinoma Arising in Tattooed Skin

    Science.gov (United States)

    Sarma, Deba P.; Dentlinger, Renee B.; Forystek, Amanda M.; Stevens, Todd; Huerter, Christopher

    2010-01-01

    Introduction. Tattoos have increasingly become accepted by mainstream Western society. As a result, the incidence of tattoo-associated dermatoses is on the rise. The presence of a poorly differentiated squamous cell carcinoma in an old tattooed skin is of interest as it has not been previously documented. Case Presentation. A 79-year-old white homeless man of European descent presented to the dermatology clinic with a painless raised nodule on his left forearm arising in a tattooed area. A biopsy of the lesion revealed a poorly differentiated squamous cell carcinoma infiltrating into a tattoo. The lesion was completely excised and the patient remains disease-free one year later. Conclusion. All previous reports of squamous cell carcinomas arising in tattoos have been well-differentiated low-grade type or keratoacanthoma-type and are considered to be coincidental rather than related to any carcinogenic effect of the tattoo pigments. Tattoo-associated poorly differentiated invasive carcinoma appears to be extremely rare. PMID:21274289

  14. Poorly Differentiated Squamous Cell Carcinoma Arising in Tattooed Skin

    Directory of Open Access Journals (Sweden)

    Deba P. Sarma

    2010-01-01

    Full Text Available Introduction. Tattoos have increasingly become accepted by mainstream Western society. As a result, the incidence of tattoo-associated dermatoses is on the rise. The presence of a poorly differentiated squamous cell carcinoma in an old tattooed skin is of interest as it has not been previously documented. Case Presentation. A 79-year-old white homeless man of European descent presented to the dermatology clinic with a painless raised nodule on his left forearm arising in a tattooed area. A biopsy of the lesion revealed a poorly differentiated squamous cell carcinoma infiltrating into a tattoo. The lesion was completely excised and the patient remains disease-free one year later. Conclusion. All previous reports of squamous cell carcinomas arising in tattoos have been well-differentiated low-grade type or keratoacanthoma-type and are considered to be coincidental rather than related to any carcinogenic effect of the tattoo pigments. Tattoo-associated poorly differentiated invasive carcinoma appears to be extremely rare.

  15. Endogenous collagen influences differentiation of human multipotent mesenchymal stromal cells.

    Science.gov (United States)

    Fernandes, Hugo; Mentink, Anouk; Bank, Ruud; Stoop, Reinout; van Blitterswijk, Clemens; de Boer, Jan

    2010-05-01

    Human multipotent mesenchymal stromal cells (hMSCs) are multipotent cells that, in the presence of appropriate stimuli, can differentiate into different lineages such as the osteogenic, chondrogenic, and adipogenic lineages. In the presence of ascorbic acid, MSCs secrete an extracellular matrix mainly composed of collagen type I. Here we assessed the potential role of endogenous collagen synthesis in hMSC differentiation and stem cell maintenance. We observed a sharp reduction in proliferation rate of hMSCs in the absence of ascorbic acid, concomitant with a reduction in osteogenesis in vitro and bone formation in vivo. In line with a positive role for collagen type I in osteogenesis, gene expression profiling of hMSCs cultured in the absence of ascorbic acid demonstrated increased expression of genes involved in adipogenesis and chondrogenesis and a reduction in expression of osteogenic genes. We also observed that matrix remodeling and anti-osteoclastogenic signals were high in the presence of ascorbic acid. The presence of collagen type I during the expansion phase of hMSCs did not affect their osteogenic and adipogenic differentiation potential. In conclusion, the collagenous matrix supports both proliferation and differentiation of osteogenic hMSCs but, on the other hand, presents signals stimulating matrix remodeling and inhibiting osteoclastogenesis.

  16. The Effect of Antidepressants on Mesenchymal Stem Cell Differentiation.

    Science.gov (United States)

    Kruk, Jeffrey S; Bermeo, Sandra; Skarratt, Kristen K; Fuller, Stephen J; Duque, Gustavo

    2018-02-01

    Use of antidepressant medications has been linked to detrimental impacts on bone mineral density and osteoporosis; however, the cellular basis behind these observations remains poorly understood. The effect does not appear to be homogeneous across the whole class of drugs and may be linked to affinity for the serotonin transporter system. In this study, we hypothesized that antidepressants have a class- and dose-dependent effect on mesenchymal stem cell (MSC) differentiation, which may affect bone metabolism. Human MSCs (hMSCs) were committed to differentiate when either adipogenic or osteogenic media was added, supplemented with five increasing concentrations of amitriptyline (0.001-10 µM), venlafaxine (0.01-25 µM), or fluoxetine (0.001-10 µM). Alizarin red staining (mineralization), alkaline phosphatase (osteoblastogenesis), and oil red O (adipogenesis) assays were performed at timed intervals. In addition, cell viability was assessed using a MTT. We found that fluoxetine had a significant inhibitory effect on mineralization. Furthermore, adipogenic differentiation of hMSC was affected by the addition of amitriptyline, venlafaxine, and fluoxetine to the media. Finally, none of the tested medications significantly affected cell survival. This study showed a divergent effect of three antidepressants on hMSC differentiation, which appears to be independent of class and dose. As fluoxetine and amitriptyline, but not venlafaxine, affected both osteoblastogenesis and adipogenesis, this inhibitory effect could be associated to the high affinity of fluoxetine to the serotonin transporter system.

  17. Effect of citrus flavonoids on HL-60 cell differentiation.

    Science.gov (United States)

    Kawaii, S; Tomono, Y; Katase, E; Ogawa, K; Yano, M

    1999-01-01

    Twenty-seven Citrus flavonoids were examined for their activity of induction of terminal differentiation of human promyelocytic leukemia cells (HL-60) by nitro blue tetrazolium (NBT) reducing, nonspecific esterase, specific esterase, and phagocytic activities. 10 flavonoids were judged to be active (percentage of NBT reducing cells was more than 40% at a concentration of 40 microM), and the rank order of potency was natsudaidain, luteolin, tangeretin, quercetin, apigenin, 3, 3, '4, '5, 6, 7, 8-heptamethoxyflavone, nobiletin, acacetin, eriodictyol, and taxifolin. These flavonoids exerted their activity in a dose-dependent manner. HL-60 cells treated with these flavonoids differentiated into mature monocyte/macrophage. The structure-activity relationship established from comparison between flavones and flavanones revealed that ortho-catechol moiety in ring B and C2-C3 double bond had an important role for induction of differentiation of HL-60. In polymethoxylated flavones, hydroxyl group at C3 and methoxyl group at C8 enhanced the differentiation-inducing activity.

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

    Directory of Open Access Journals (Sweden)

    Mathilde Couteaudier

    2015-03-01

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

  19. Senescence from glioma stem cell differentiation promotes tumor growth

    International Nuclear Information System (INIS)

    Ouchi, Rie; Okabe, Sachiko; Migita, Toshiro; Nakano, Ichiro; Seimiya, Hiroyuki

    2016-01-01

    Glioblastoma (GBM) is a lethal brain tumor composed of heterogeneous cellular populations including glioma stem cells (GSCs) and differentiated non-stem glioma cells (NSGCs). While GSCs are involved in tumor initiation and propagation, NSGCs' role remains elusive. Here, we demonstrate that NSGCs undergo senescence and secrete pro-angiogenic proteins, boosting the GSC-derived tumor formation in vivo. We used a GSC model that maintains stemness in neurospheres, but loses the stemness and differentiates into NSGCs upon serum stimulation. These NSGCs downregulated telomerase, shortened telomeres, and eventually became senescent. The senescent NSGCs released pro-angiogenic proteins, including vascular endothelial growth factors and senescence-associated interleukins, such as IL-6 and IL-8. Conditioned medium from senescent NSGCs promoted proliferation of brain microvascular endothelial cells, and mixed implantation of GSCs and senescent NSGCs into mice enhanced the tumorigenic potential of GSCs. The senescent NSGCs seem to be clinically relevant, because both clinical samples and xenografts of GBM contained tumor cells that expressed the senescence markers. Our data suggest that senescent NSGCs promote malignant progression of GBM in part via paracrine effects of the secreted proteins. - Highlights: • Non-stem glioma cells (NSGCs) lose telomerase and eventually become senescent. • Senescent NSGCs secrete pro-angiogenic proteins, such as VEGFs, IL-6, and IL-8. • Senescent NSGCs enhance the growth of brain microvascular endothelial cells. • Senescent NSGCs enhance the tumorigenic potential of glioma stem cells in vivo.

  20. NFIX Regulates Neural Progenitor Cell Differentiation During Hippocampal Morphogenesis

    Science.gov (United States)

    Heng, Yee Hsieh Evelyn; McLeay, Robert C.; Harvey, Tracey J.; Smith, Aaron G.; Barry, Guy; Cato, Kathleen; Plachez, Céline; Little, Erica; Mason, Sharon; Dixon, Chantelle; Gronostajski, Richard M.; Bailey, Timothy L.; Richards, Linda J.; Piper, Michael

    2014-01-01

    Neural progenitor cells have the ability to give rise to neurons and glia in the embryonic, postnatal and adult brain. During development, the program regulating whether these cells divide and self-renew or exit the cell cycle and differentiate is tightly controlled, and imbalances to the normal trajectory of this process can lead to severe functional consequences. However, our understanding of the molecular regulation of these fundamental events remains limited. Moreover, processes underpinning development of the postnatal neurogenic niches within the cortex remain poorly defined. Here, we demonstrate that Nuclear factor one X (NFIX) is expressed by neural progenitor cells within the embryonic hippocampus, and that progenitor cell differentiation is delayed within Nfix−/− mice. Moreover, we reveal that the morphology of the dentate gyrus in postnatal Nfix−/− mice is abnormal, with fewer subgranular zone neural progenitor cells being generated in the absence of this transcription factor. Mechanistically, we demonstrate that the progenitor cell maintenance factor Sry-related HMG box 9 (SOX9) is upregulated in the hippocampus of Nfix−/− mice and demonstrate that NFIX can repress Sox9 promoter-driven transcription. Collectively, our findings demonstrate that NFIX plays a central role in hippocampal morphogenesis, regulating the formation of neuronal and glial populations within this structure. PMID:23042739

  1. Senescence from glioma stem cell differentiation promotes tumor growth

    Energy Technology Data Exchange (ETDEWEB)

    Ouchi, Rie [Division of Molecular Biotherapy, Cancer Chemotherapy Center, Japanese Foundation for Cancer Research, 3-8-31 Ariake, Koto-ku, Tokyo 135-8550 (Japan); Laboratory of Molecular Target Therapy of Cancer, Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, The University of Tokyo, 3-8-31 Ariake, Koto-ku, Tokyo 135-8550 (Japan); Okabe, Sachiko; Migita, Toshiro [Division of Molecular Biotherapy, Cancer Chemotherapy Center, Japanese Foundation for Cancer Research, 3-8-31 Ariake, Koto-ku, Tokyo 135-8550 (Japan); Nakano, Ichiro [Department of Neurosurgery, Comprehensive Cancer Center, University of Alabama at Birmingham, 1824 6th Avenue South, Birmingham, AL 35233 (United States); Seimiya, Hiroyuki, E-mail: hseimiya@jfcr.or.jp [Division of Molecular Biotherapy, Cancer Chemotherapy Center, Japanese Foundation for Cancer Research, 3-8-31 Ariake, Koto-ku, Tokyo 135-8550 (Japan); Laboratory of Molecular Target Therapy of Cancer, Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, The University of Tokyo, 3-8-31 Ariake, Koto-ku, Tokyo 135-8550 (Japan)

    2016-02-05

    Glioblastoma (GBM) is a lethal brain tumor composed of heterogeneous cellular populations including glioma stem cells (GSCs) and differentiated non-stem glioma cells (NSGCs). While GSCs are involved in tumor initiation and propagation, NSGCs' role remains elusive. Here, we demonstrate that NSGCs undergo senescence and secrete pro-angiogenic proteins, boosting the GSC-derived tumor formation in vivo. We used a GSC model that maintains stemness in neurospheres, but loses the stemness and differentiates into NSGCs upon serum stimulation. These NSGCs downregulated telomerase, shortened telomeres, and eventually became senescent. The senescent NSGCs released pro-angiogenic proteins, including vascular endothelial growth factors and senescence-associated interleukins, such as IL-6 and IL-8. Conditioned medium from senescent NSGCs promoted proliferation of brain microvascular endothelial cells, and mixed implantation of GSCs and senescent NSGCs into mice enhanced the tumorigenic potential of GSCs. The senescent NSGCs seem to be clinically relevant, because both clinical samples and xenografts of GBM contained tumor cells that expressed the senescence markers. Our data suggest that senescent NSGCs promote malignant progression of GBM in part via paracrine effects of the secreted proteins. - Highlights: • Non-stem glioma cells (NSGCs) lose telomerase and eventually become senescent. • Senescent NSGCs secrete pro-angiogenic proteins, such as VEGFs, IL-6, and IL-8. • Senescent NSGCs enhance the growth of brain microvascular endothelial cells. • Senescent NSGCs enhance the tumorigenic potential of glioma stem cells in vivo.

  2. TCDD alters medial epithelial cell differentiation during palatogenesis

    International Nuclear Information System (INIS)

    Abbott, B.D.; Birnbaum, L.S.

    1989-01-01

    2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is a widely distributed, persistent environmental contaminant that is teratogenic in mice, where it induces hydronephrosis and cleft palate. The incidence of clefting has been shown to be dose dependent after exposure on either gestation Day (GD) 10 or 12, although the embryo is more susceptible on GD 12. TCDD-exposed palatal shelves meet but do not fuse, and programmed cell death of the medial epithelial cells is inhibited. The mechanism of action through which TCDD alters the program of medial cell development has not been examined in earlier studies, and it is not known whether the mechanism is the same regardless of the dose or developmental stage of exposure. In this study, C57BL/6N mice, a strain sensitive to TCDD, were dosed orally on GD 10 or 12 with 0, 6, 12, 24, or 30 micrograms/kg body wt, in 10 ml corn oil/kg. Embryonic palatal shelves were examined on GD 14, 15, or 16. The degree of palatal closure, epithelial surface morphology, and cellular ultrastructure, the incorporation of [3H]TdR, the expression of EGF receptors, and the binding of 125I-EGF were assessed. After exposure on GD 10 or 12, TCDD altered the differentiation pathway of the medial epithelial cells. The palatal shelves were of normal size and overall morphology, but fusion of the medial epithelia of the opposing shelves did not occur. TCDD prevented programmed cell death of the medial peridermal cells. The expression of EGF receptors by medial cells continued through Day 16 and the receptors were able to bind ligand. The medial cells differentiated into a stratified, squamous, keratinizing epithelium. The shift in phenotype to an oral-like epithelium occurred after exposure on either GD 10 or 12. At the lower dose (6 micrograms/kg), fewer cleft palates were produced, but those shelves which did respond had a fully expressed shift in differentiation

  3. Differential cytokine contributions of perivascular haematopoietic stem cell niches.

    Science.gov (United States)

    Asada, Noboru; Kunisaki, Yuya; Pierce, Halley; Wang, Zichen; Fernandez, Nicolas F; Birbrair, Alexander; Ma'ayan, Avi; Frenette, Paul S

    2017-03-01

    Arterioles and sinusoids of the bone marrow (BM) are accompanied by stromal cells that express nerve/glial antigen 2 (NG2) and leptin receptor (LepR), and constitute specialized niches that regulate quiescence and proliferation of haematopoietic stem cells (HSCs). However, how niche cells differentially regulate HSC functions remains unknown. Here, we show that the effects of cytokines regulating HSC functions are dependent on the producing cell sources. Deletion of chemokine C-X-C motif ligand 12 (Cxcl12) or stem cell factor (Scf) from all perivascular cells marked by nestin-GFP dramatically depleted BM HSCs. Selective Cxcl12 deletion from arteriolar NG2 + cells, but not from sinusoidal LepR + cells, caused HSC reductions and altered HSC localization in BM. By contrast, deletion of Scf in LepR + cells, but not NG2 + cells, led to reductions in BM HSC numbers. These results uncover distinct contributions of cytokines derived from perivascular cells in separate vascular niches to HSC maintenance.

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

    Science.gov (United States)

    Beane, Olivia S; Darling, Eric M

    2012-10-01

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

  5. Interleukin 4: signalling mechanisms and control of T cell differentiation.

    Science.gov (United States)

    Paul, W E

    1997-01-01

    Interleukin 4 (IL-4) is a pleiotropic type I cytokine that controls both growth and differentiation among haemopoietic and non-haemopoietic cells. Its receptor is a heterodimer. One chain, the IL-4R alpha chain, binds IL-4 with high affinity and determines the nature of the biochemical signals that are induced. The second chain, gamma c, is required for the induction of such signals. IL-4-mediated growth depends upon activation events that involve phosphorylation of Y497 of IL-4R alpha, leading to the binding and phosphorylation of 4PS/IRS-2 in haemopoietic cells and of IRS-1 in non-haemopoietic cells. By contrast, IL-4-mediated differentiation events depend upon more distal regions of the IL-4R alpha chain that include a series of STAT-6 binding sites. The distinctive roles of these receptor domains was verified by receptor-reconstruction experiments. The 'growth' and 'differentiation' domains of the IL-4R alpha chain, independently expressed as chimeric structures with a truncated version of the IL-2R beta chain, were shown to convey their functions to the hybrid receptor. The critical role of STAT-6 in IL-4-mediated gene activation and differentiation was made clear by the finding that lymphocytes from STAT-6 knockout mice are strikingly deficient in these functions but have retained the capacity to grow, at least partially, in response to IL-4. IL-4 plays a central role in determining the phenotype of naive CD4+ T cells. In the presence of IL-4, newly primed naive T cells develop into IL-4 producers while in its absence they preferentially become gamma-interferon (IFN-gamma) producers. Recently, a specialized subpopulation of T cells, CD4+/NK1.1+ cells, has been shown to produce large amounts of IL-4 upon stimulation. Two examples of mice with deficiencies in these cells are described--beta 2-microglobulin knockout mice and SJL mice. Both show defects in the development of IL-4-producing cells and in the increase in serum IgE in response to stimulation with the

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

    Science.gov (United States)

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

    2017-01-01

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

  7. Biophysical characteristics reveal neural stem cell differentiation potential.

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    Fatima H Labeed

    Full Text Available Distinguishing human neural stem/progenitor cell (huNSPC populations that will predominantly generate neurons from those that produce glia is currently hampered by a lack of sufficient cell type-specific surface markers predictive of fate potential. This limits investigation of lineage-biased progenitors and their potential use as therapeutic agents. A live-cell biophysical and label-free measure of fate potential would solve this problem by obviating the need for specific cell surface markers.We used dielectrophoresis (DEP to analyze the biophysical, specifically electrophysiological, properties of cortical human and mouse NSPCs that vary in differentiation potential. Our data demonstrate that the electrophysiological property membrane capacitance inversely correlates with the neurogenic potential of NSPCs. Furthermore, as huNSPCs are continually passaged they decrease neuron generation and increase membrane capacitance, confirming that this parameter dynamically predicts and negatively correlates with neurogenic potential. In contrast, differences in membrane conductance between NSPCs do not consistently correlate with the ability of the cells to generate neurons. DEP crossover frequency, which is a quantitative measure of cell behavior in DEP, directly correlates with neuron generation of NSPCs, indicating a potential mechanism to separate stem cells biased to particular differentiated cell fates.We show here that whole cell membrane capacitance, but not membrane conductance, reflects and predicts the neurogenic potential of human and mouse NSPCs. Stem cell biophysical characteristics therefore provide a completely novel and quantitative measure of stem cell fate potential and a label-free means to identify neuron- or glial-biased progenitors.

  8. Cell population structure prior to bifurcation predicts efficiency of directed differentiation in human induced pluripotent cells.

    Science.gov (United States)

    Bargaje, Rhishikesh; Trachana, Kalliopi; Shelton, Martin N; McGinnis, Christopher S; Zhou, Joseph X; Chadick, Cora; Cook, Savannah; Cavanaugh, Christopher; Huang, Sui; Hood, Leroy

    2017-02-28

    Steering the differentiation of induced pluripotent stem cells (iPSCs) toward specific cell types is crucial for patient-specific disease modeling and drug testing. This effort requires the capacity to predict and control when and how multipotent progenitor cells commit to the desired cell fate. Cell fate commitment represents a critical state transition or "tipping point" at which complex systems undergo a sudden qualitative shift. To characterize such transitions during iPSC to cardiomyocyte differentiation, we analyzed the gene expression patterns of 96 developmental genes at single-cell resolution. We identified a bifurcation event early in the trajectory when a primitive streak-like cell population segregated into the mesodermal and endodermal lineages. Before this branching point, we could detect the signature of an imminent critical transition: increase in cell heterogeneity and coordination of gene expression. Correlation analysis of gene expression profiles at the tipping point indicates transcription factors that drive the state transition toward each alternative cell fate and their relationships with specific phenotypic readouts. The latter helps us to facilitate small molecule screening for differentiation efficiency. To this end, we set up an analysis of cell population structure at the tipping point after systematic variation of the protocol to bias the differentiation toward mesodermal or endodermal cell lineage. We were able to predict the proportion of cardiomyocytes many days before cells manifest the differentiated phenotype. The analysis of cell populations undergoing a critical state transition thus affords a tool to forecast cell fate outcomes and can be used to optimize differentiation protocols to obtain desired cell populations.

  9. Diclofenac and triamcinolone acetonide impair tenocytic differentiation and promote adipocytic differentiation of mesenchymal stem cells

    OpenAIRE

    Fredriksson, Maritha; Li, Yan; St?lman, Anders; Haldos?n, Lars-Arne; Fell?nder-Tsai, Li

    2013-01-01

    Background Tendinopathies are often empirically treated with oral/topical nonsteroidal anti-inflammatory medications and corticosteroid injections despite their unclear effects on tendon regeneration. Recent studies indicate that tendon progenitors exhibit stem cell-like properties, i.e., differentiation to osteoblasts, adipocytes, and chondrocytes, in addition to tenocytes. Our present study aims at understanding the effects of triamcinolone acetonide and diclofenac on tenocytic differentiat...

  10. In Vitro Differentiation of Human Mesenchymal Stem Cells into Functional Cardiomyocyte-like Cells.

    Science.gov (United States)

    Szaraz, Peter; Gratch, Yarden S; Iqbal, Farwah; Librach, Clifford L

    2017-08-09

    Myocardial infarction and the subsequent ischemic cascade result in the extensive loss of cardiomyocytes, leading to congestive heart failure, the leading cause of mortality worldwide. Mesenchymal stem cells (MSCs) are a promising option for cell-based therapies to replace current, invasive techniques. MSCs can differentiate into mesenchymal lineages, including cardiac cell types, but complete differentiation into functional cells has not yet been achieved. Previous methods of differentiation were based on pharmacological agents or growth factors. However, more physiologically relevant strategies can also enable MSCs to undergo cardiomyogenic transformation. Here, we present a differentiation method using MSC aggregates on cardiomyocyte feeder layers to produce cardiomyocyte-like contracting cells. Human umbilical cord perivascular cells (HUCPVCs) have been shown to have a greater differentiation potential than commonly investigated MSC types, such as bone marrow MSCs (BMSCs). As an ontogenetically younger source, we investigated the cardiomyogenic potential of first-trimester (FTM) HUCPVCs compared to older sources. FTM HUCPVCs are a novel, rich source of MSCs that retain their in utero immunoprivileged properties when cultured in vitro. Using this differentiation protocol, FTM and term HUCPVCs achieved significantly increased cardiomyogenic differentiation compared to BMSCs, as indicated by the increased expression of cardiomyocyte markers (i.e., myocyte enhancer factor 2C, cardiac troponin T, heavy chain cardiac myosin, signal regulatory protein α, and connexin 43). They also maintained significantly lower immunogenicity, as demonstrated by their lower HLA-A expression and higher HLA-G expression. Applying aggregate-based differentiation, FTM HUCPVCs showed increased aggregate formation potential and generated contracting cells clusters within 1 week of co-culture on cardiac feeder layers, becoming the first MSC type to do so. Our results demonstrate that this

  11. Equine induced pluripotent stem cells have a reduced tendon differentiation capacity compared to embryonic stem cells

    Directory of Open Access Journals (Sweden)

    Emma Patricia Bavin

    2015-11-01

    Full Text Available Tendon injuries occur commonly in horses and their repair through scar tissue formation predisposes horses to a high rate of re-injury. Pluripotent stem cells may provide a cell replacement therapy to improve tendon tissue regeneration and lower the frequency of re-injury. We have previously demonstrated that equine embryonic stem cells (ESCs differentiate into the tendon cell lineage upon injection into the damaged horse tendon and can differentiate into functional tendon cells in vitro to generate artificial tendons. Induced pluripotent stem cells (iPSCs have now been derived from horses but, to date, there are no reports on their ability to differentiate into tendon cells. As iPSCs can be produced from adult cell types, they provide a more accessible source of cells than ESCs, which require the use of horse embryos. The aim of this study was to compare tendon differentiation by ESCs and iPSCs produced through two independent methods. In 2-dimensional differentiation assays the iPSCs expressed tendon associated genes and proteins, which were enhanced by the presence of transforming growth factor-β3. However, in 3-dimensional differentiation assays the iPSCs failed to differentiate into functional tendon cells and generate artificial tendons. These results demonstrate the utility of the 3-dimensional in vitro tendon assay for measuring tendon differentiation and the need for more detailed studies to be performed on equine iPSCs to identify and understand their epigenetic differences from pluripotent ESCs prior to their clinical application.

  12. Directed Differentiation of Human Pluripotent Stem Cells to Microglia

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    Panagiotis Douvaras

    2017-06-01

    Full Text Available Microglia, the immune cells of the brain, are crucial to proper development and maintenance of the CNS, and their involvement in numerous neurological disorders is increasingly being recognized. To improve our understanding of human microglial biology, we devised a chemically defined protocol to generate human microglia from pluripotent stem cells. Myeloid progenitors expressing CD14/CX3CR1 were generated within 30 days of differentiation from both embryonic and induced pluripotent stem cells (iPSCs. Further differentiation of the progenitors resulted in ramified microglia with highly motile processes, expressing typical microglial markers. Analyses of gene expression and cytokine release showed close similarities between iPSC-derived (iPSC-MG and human primary microglia as well as clear distinctions from macrophages. iPSC-MG were able to phagocytose and responded to ADP by producing intracellular Ca2+ transients, whereas macrophages lacked such response. The differentiation protocol was highly reproducible across several pluripotent stem cell lines.

  13. An Alu-like RNA promotes cell differentiation and reduces malignancy of human neuroblastoma cells

    OpenAIRE

    Castelnuovo Manuele; Massone Sara; Tasso Roberta; Fiorino Gloria; Gatti Monica; Robello Mauro; Gatta Elena; Berger Audrey; Strub Katharina; Florio Tullio; Dieci Giorgio; Cancedda Ranieri; Pagano Aldo

    2010-01-01

    Neuroblastoma (NB) is a pediatric cancer characterized by remarkable cell heterogeneity within the tumor nodules. Here, we demonstrate that the synthesis of a pol III-transcribed noncoding (nc) RNA (NDM29) strongly restricts NB development by promoting cell differentiation, a drop of malignancy processes, and a dramatic reduction of the tumor initiating cell (TIC) fraction in the NB cell population. Notably, the overexpression of NDM29 also confers to malignant NB cells an unpredicted suscept...

  14. Simulated Microgravity Modulates Differentiation Processes of Embryonic Stem Cells

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    Vaibhav Shinde

    2016-04-01

    Full Text Available Background/Aims: Embryonic developmental studies under microgravity conditions in space are very limited. To study the effects of altered gravity on the embryonic development processes we established an in vitro methodology allowing differentiation of mouse embryonic stem cells (mESCs under simulated microgravity within a fast-rotating clinostat (clinorotation and capture of microarray-based gene signatures. Methods: The differentiating mESCs were cultured in a 2D pipette clinostat. The microarray and bioinformatics tools were used to capture genes that are deregulated by simulated microgravity and their impact on developmental biological processes. Results: The data analysis demonstrated that differentiation of mESCs in pipettes for 3 days resultet to early germ layer differentiation and then to the different somatic cell types after further 7 days of differentiation in the Petri dishes. Clinorotation influences differentiation as well as non-differentiation related biological processes like cytoskeleton related 19 genes were modulated. Notably, simulated microgravity deregulated genes Cyr61, Thbs1, Parva, Dhrs3, Jun, Tpm1, Fzd2 and Dll1 are involved in heart morphogenesis as an acute response on day 3. If the stem cells were further cultivated under normal gravity conditions (1 g after clinorotation, the expression of cardiomyocytes specific genes such as Tnnt2, Rbp4, Tnni1, Csrp3, Nppb and Mybpc3 on day 10 was inhibited. This correlated well with a decreasing beating activity of the 10-days old embryoid bodies (EBs. Finally, we captured Gadd45g, Jun, Thbs1, Cyr61and Dll1 genes whose expressions were modulated by simulated microgravity and by real microgravity in various reported studies. Simulated microgravity also deregulated genes belonging to the MAP kinase and focal dhesion signal transduction pathways. Conclusion: One of the most prominent biological processes affected by simulated microgravity was the process of cardiomyogenesis. The

  15. Single-cell cloning of colon cancer stem cells reveals a multi-lineage differentiation capacity

    NARCIS (Netherlands)

    Vermeulen, L.; Todaro, M.; de Sousa E Melo, F.; Sprick, M. R.; Kemper, K.; Alea, M. Perez; Richel, D. J.; Stassi, G.; Medema, J. P.

    2008-01-01

    Colon carcinoma is one of the leading causes of death from cancer and is characterized by a heterogenic pool of cells with distinct differentiation patterns. Recently, it was reported that a population of undifferentiated cells from a primary tumor, so-called cancer stem cells (CSC), can

  16. Differentiation of purified malignant B cells induced by PMA or by activated normal T cells

    NARCIS (Netherlands)

    van Kooten, C.; Rensink, I.; Aarden, L.; van Oers, R.

    1993-01-01

    We studied the in vitro differentiation (immunoglobulin production) of purified malignant B cells of 21 patients with different B-cell malignancies, including chronic lymphocytic leukemia (CLL), prolymphocytic leukemia (PLL), hairy cell leukemia (HCL) and non-Hodgkin lymphoma (NHL). Direct

  17. Mouse Embryonic Stem Cell Adherent Cell Differentiation and Cytotoxicity (ACDC) assay

    Science.gov (United States)

    The Embryonic Stem Cell Test (EST) is an assay which evaluates xenobiotic-induced effects using three endpoints: mouse embryonic stem cell (mESC) differentiation, mESC viability, and 3T3-cell viability. Our research goal was to develop an improved high-throughput assay by establi...

  18. A Cell Model to Evaluate Chemical Effects on Adult Human Cardiac Progenitor Cell Differentiation and Function

    Science.gov (United States)

    Adult cardiac stem cells (CSC) and progenitor cells (CPC) represent a population of cells in the heart critical for its regeneration and function over a lifetime. The impact of chemicals on adult human CSC/CPC differentiation and function is unknown. Research was conducted to dev...

  19. JMJD5 (Jumonji Domain-containing 5) Associates with Spindle Microtubules and Is Required for Proper Mitosis.

    Science.gov (United States)

    He, Zhimin; Wu, Junyu; Su, Xiaonan; Zhang, Ye; Pan, Lixia; Wei, Huimin; Fang, Qiang; Li, Haitao; Wang, Da-Liang; Sun, Fang-Lin

    2016-02-26

    Precise mitotic spindle assembly is a guarantee of proper chromosome segregation during mitosis. Chromosome instability caused by disturbed mitosis is one of the major features of various types of cancer. JMJD5 has been reported to be involved in epigenetic regulation of gene expression in the nucleus, but little is known about its function in mitotic process. Here we report the unexpected localization and function of JMJD5 in mitotic progression. JMJD5 partially accumulates on mitotic spindles during mitosis, and depletion of JMJD5 results in significant mitotic arrest, spindle assembly defects, and sustained activation of the spindle assembly checkpoint (SAC). Inactivating SAC can efficiently reverse the mitotic arrest caused by JMJD5 depletion. Moreover, JMJD5 is found to interact with tubulin proteins and associate with microtubules during mitosis. JMJD5-depleted cells show a significant reduction of α-tubulin acetylation level on mitotic spindles and fail to generate enough interkinetochore tension to satisfy the SAC. Further, JMJD5 depletion also increases the susceptibility of HeLa cells to the antimicrotubule agent. Taken together, these results suggest that JMJD5 plays an important role in regulating mitotic progression, probably by modulating the stability of spindle microtubules. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

  20. Neuron-NG2 Cell Synapses: Novel Functions for Regulating NG2 Cell Proliferation and Differentiation

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    Qian-Kun Yang

    2013-01-01

    Full Text Available NG2 cells are a population of CNS cells that are distinct from neurons, mature oligodendrocytes, astrocytes, and microglia. These cells can be identified by their NG2 proteoglycan expression. NG2 cells have a highly branched morphology, with abundant processes radiating from the cell body, and express a complex set of voltage-gated channels, AMPA/kainate, and GABA receptors. Neurons notably form classical and nonclassical synapses with NG2 cells, which have varied characteristics and functions. Neuron-NG2 cell synapses could fine-tune NG2 cell activities, including the NG2 cell cycle, differentiation, migration, and myelination, and may be a novel potential therapeutic target for NG2 cell-related diseases, such as hypoxia-ischemia injury and periventricular leukomalacia. Furthermore, neuron-NG2 cell synapses may be correlated with the plasticity of CNS in adulthood with the synaptic contacts passing onto their progenies during proliferation, and synaptic contacts decrease rapidly upon NG2 cell differentiation. In this review, we highlight the characteristics of classical and nonclassical neuron-NG2 cell synapses, the potential functions, and the fate of synaptic contacts during proliferation and differentiation, with the emphasis on the regulation of the NG2 cell cycle by neuron-NG2 cell synapses and their potential underlying mechanisms.

  1. Mash1-expressing cells could differentiate to type III cells in adult mouse taste buds.

    Science.gov (United States)

    Takagi, Hiroki; Seta, Yuji; Kataoka, Shinji; Nakatomi, Mitsushiro; Toyono, Takashi; Kawamoto, Tatsuo

    2018-03-10

    The gustatory cells in taste buds have been identified as paraneuronal; they possess characteristics of both neuronal and epithelial cells. Like neurons, they form synapses, store and release transmitters, and are capable of generating an action potential. Like epithelial cells, taste cells have a limited life span and are regularly replaced throughout life. However, little is known about the molecular mechanisms that regulate taste cell genesis and differentiation. In the present study, to begin to understand these mechanisms, we investigated the role of Mash1-positive cells in regulating adult taste bud cell differentiation through the loss of Mash1-positive cells using the Cre-loxP system. We found that the cells expressing type III cell markers-aromatic L-amino acid decarboxylase (AADC), carbonic anhydrase 4 (CA4), glutamate decarboxylase 67 (GAD67), neural cell adhesion molecule (NCAM), and synaptosomal-associated protein 25 (SNAP25)-were significantly reduced in the circumvallate taste buds after the administration of tamoxifen. However, gustducin and phospholipase C beta2 (PLC beta2)-markers of type II taste bud cells-were not significantly changed in the circumvallate taste buds after the administration of tamoxifen. These results suggest that Mash1-positive cells could be differentiated to type III cells, not type II cells in the taste buds.

  2. Is Melanoma a stem cell tumor? Identification of neurogenic proteins in trans-differentiated cells

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    Chan Linda S

    2005-03-01

    Full Text Available Abstract Background Although several genes and proteins have been implicated in the development of melanomas, the molecular mechanisms involved in the development of these tumors are not well understood. To gain a better understanding of the relationship between the cell growth, tumorigenesis and differentiation, we have studied a highly malignant cat melanoma cell line that trans-differentiates into neuronal cells after exposure to a feline endogenous retrovirus RD114. Methods To define the repertoire of proteins responsible for the phenotypic differences between melanoma and its counterpart trans-differentiated neuronal cells we have applied proteomics technology and compared protein profiles of the two cell types and identified differentially expressed proteins by 2D-gel electrophoresis, image analyses and mass spectrometry. Results The melanoma and trans-differentiated neuronal cells could be distinguished by the presence of distinct sets of proteins in each. Although approximately 60–70% of the expressed proteins were shared between the two cell types, twelve proteins were induced de novo after infection of melanoma cells with RD114 virus in vitro. Expression of these proteins in trans-differentiated cells was significantly associated with concomitant down regulation of growth promoting proteins and up-regulation of neurogenic proteins (p = 95% proteins expressed in trans-differentiated cells could be associated with the development, differentiation and regulation of nervous system cells. Conclusion Our results indicate that the cat melanoma cells have the ability to differentiate into distinct neuronal cell types and they express proteins that are essential for self-renewal. Since melanocytes arise from the neural crest of the embryo, we conclude that this melanoma arose from embryonic precursor stem cells. This model system provides a unique opportunity to identify domains of interactions between the expressed proteins that halt the

  3. IL-17 inhibits chondrogenic differentiation of human mesenchymal stem cells.

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    Masahiro Kondo

    Full Text Available OBJECTIVE: Mesenchymal stem cells (MSCs can differentiate into cells of mesenchymal lineages, such as osteoblasts and chondrocytes. Here we investigated the effects of IL-17, a key cytokine in chronic inflammation, on chondrogenic differentiation of human MSCs. METHODS: Human bone marrow MSCs were pellet cultured in chondrogenic induction medium containing TGF-β3. Chondrogenic differentiation was detected by cartilage matrix accumulation and chondrogenic marker gene expression. RESULTS: Over-expression of cartilage matrix and chondrogenic marker genes was noted in chondrogenic cultures, but was inhibited by IL-17 in a dose-dependent manner. Expression and phosphorylation of SOX9, the master transcription factor for chondrogenesis, were induced within 2 days and phosphorylated SOX9 was stably maintained until day 21. IL-17 did not alter total SOX9 expression, but significantly suppressed SOX9 phosphorylation in a dose-dependent manner. At day 7, IL-17 also suppressed the activity of cAMP-dependent protein kinase A (PKA, which is known to phosphorylate SOX9. H89, a selective PKA inhibitor, also suppressed SOX9 phosphorylation, expression of chondrogenic markers and cartilage matrix, and also decreased chondrogenesis. CONCLUSIONS: IL-17 inhibited chondrogenesis of human MSCs through the suppression of PKA activity and SOX9 phosphorylation. These results suggest that chondrogenic differentiation of MSCs can be inhibited by a mechanism triggered by IL-17 under chronic inflammation.

  4. Effects of matrix elasticity and cell density on human mesenchymal stem cells differentiation.

    Science.gov (United States)

    Xue, Ruyue; Li, Julie Yi-Shuan; Yeh, Yiting; Yang, Li; Chien, Shu

    2013-09-01

    Human mesenchymal stem cells (hMSCs) can differentiate into various cell types, including osteogenic and chondrogenic cells. The matrix elasticity and cell seeding density are important factors in hMSCs differentiation. We cultured hMSCs at different seeding densities on polyacrylamide hydrogels with different stiffness corresponding to Young's moduli of 1.6 ± 0.3 and 40 ± 3.6 kPa. The promotion of osteogenic marker expression by hard gel is overridden by a high seeding density. Cell seeding density, however, did not influence the chondrogenic marker expressions induced by soft gel. These findings suggest that interplays between cell-matrix and cell-cell interactions contribute to hMSCs differentiation. The promotion of osteogenic differentiation on hard matrix was shown to be mediated through the Ras pathway. Inhibition of Ras (RasN17) significantly decreased ERK, Smad1/5/8 and AKT activation, and osteogenic markers expression. However, constitutively active Ras (RasV12) had little effect on osteogenic marker expression, suggesting that the Ras pathways are necessary but not sufficient for osteogenesis. Taken together, our results indicate that matrix elasticity and cell density are important microenvironmental cues driving hMSCs proliferation and differentiation. Copyright © 2013 Orthopaedic Research Society.

  5. Gene function in early mouse embryonic stem cell differentiation

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    Campbell Pearl A

    2007-03-01

    Full Text Available Abstract Background Little is known about the genes that drive embryonic stem cell differentiation. However, such knowledge is necessary if we are to exploit the therapeutic potential of stem cells. To uncover the genetic determinants of mouse embryonic stem cell (mESC differentiation, we have generated and analyzed 11-point time-series of DNA microarray data for three biologically equivalent but genetically distinct mESC lines (R1, J1, and V6.5 undergoing undirected differentiation into embryoid bodies (EBs over a period of two weeks. Results We identified the initial 12 hour period as reflecting the early stages of mESC differentiation and studied probe sets showing consistent changes of gene expression in that period. Gene function analysis indicated significant up-regulation of genes related to regulation of transcription and mRNA splicing, and down-regulation of genes related to intracellular signaling. Phylogenetic analysis indicated that the genes showing the largest expression changes were more likely to have originated in metazoans. The probe sets with the most consistent gene changes in the three cell lines represented 24 down-regulated and 12 up-regulated genes, all with closely related human homologues. Whereas some of these genes are known to be involved in embryonic developmental processes (e.g. Klf4, Otx2, Smn1, Socs3, Tagln, Tdgf1, our analysis points to others (such as transcription factor Phf21a, extracellular matrix related Lama1 and Cyr61, or endoplasmic reticulum related Sc4mol and Scd2 that have not been previously related to mESC function. The majority of identified functions were related to transcriptional regulation, intracellular signaling, and cytoskeleton. Genes involved in other cellular functions important in ESC differentiation such as chromatin remodeling and transmembrane receptors were not observed in this set. Conclusion Our analysis profiles for the first time gene expression at a very early stage of m

  6. APLP2 regulates neuronal stem cell differentiation during cortical development.

    Science.gov (United States)

    Shariati, S Ali M; Lau, Pierre; Hassan, Bassem A; Müller, Ulrike; Dotti, Carlos G; De Strooper, Bart; Gärtner, Annette

    2013-03-01

    Expression of amyloid precursor protein (APP) and its two paralogues, APLP1 and APLP2 during brain development coincides with key cellular events such as neuronal differentiation and migration. However, genetic knockout and shRNA studies have led to contradictory conclusions about their role during embryonic brain development. To address this issue, we analysed in depth the role of APLP2 during neurogenesis by silencing APLP2 in vivo in an APP/APLP1 double knockout mouse background. We find that under these conditions cortical progenitors remain in their undifferentiated state much longer, displaying a higher number of mitotic cells. In addition, we show that neuron-specific APLP2 downregulation does not impact the speed or position of migrating excitatory cortical neurons. In summary, our data reveal that APLP2 is specifically required for proper cell cycle exit of neuronal progenitors, and thus has a distinct role in priming cortical progenitors for neuronal differentiation.

  7. Radiation transformation in differentiated human cells in culture

    International Nuclear Information System (INIS)

    Mothersill, C.; Seymour, C.; Moriarty, M.; Malone, J.; Byrne, P.; Hennessy, T.

    1986-01-01

    A tissue culture technique is described for human thyroid tissue as an approach to studying mechanisms of human radiation carcinogenesis. Normal human tissue obtained from surgery is treated in one of two ways, depending upon size of specimen. Large pieces are completely digested in trypsin/ collagenase solution to a single cell suspension. Small pieces of tissue are plated as explants following partial digestion in trypsin/collagenase solution. Following irradiation of the primary differentiated monolayers (normally 10 days after plating), the development of transformed characteristics is monitored in the subsequent subcultures. A very high level of morphological and functional differentiation is apparent in the primary cultures. Over a period of approx. 6 months, the irradiated surviving cells continue to grow in culture, unlike the unirradiated controls which senesce after 2-3 subcultures. (UK)

  8. Antigen Availability Shapes T Cell Differentiation and Function during Tuberculosis.

    Science.gov (United States)

    Moguche, Albanus O; Musvosvi, Munyaradzi; Penn-Nicholson, Adam; Plumlee, Courtney R; Mearns, Helen; Geldenhuys, Hennie; Smit, Erica; Abrahams, Deborah; Rozot, Virginie; Dintwe, One; Hoff, Søren T; Kromann, Ingrid; Ruhwald, Morten; Bang, Peter; Larson, Ryan P; Shafiani, Shahin; Ma, Shuyi; Sherman, David R; Sette, Alessandro; Lindestam Arlehamn, Cecilia S; McKinney, Denise M; Maecker, Holden; Hanekom, Willem A; Hatherill, Mark; Andersen, Peter; Scriba, Thomas J; Urdahl, Kevin B

    2017-06-14

    CD4 T cells are critical for protective immunity against Mycobacterium tuberculosis (Mtb), the cause of tuberculosis (TB). Yet to date, TB vaccine candidates that boost antigen-specific CD4 T cells have conferred little or no protection. Here we examined CD4 T cell responses to two leading TB vaccine antigens, ESAT-6 and Ag85B, in Mtb-infected mice and in vaccinated humans with and without underlying Mtb infection. In both species, Mtb infection drove ESAT-6-specific T cells to be more differentiated than Ag85B-specific T cells. The ability of each T cell population to control Mtb in the lungs of mice was restricted for opposite reasons: Ag85B-specific T cells were limited by reduced antigen expression during persistent infection, whereas ESAT-6-specific T cells became functionally exhausted due to chronic antigenic stimulation. Our findings suggest that different vaccination strategies will be required to optimize protection mediated by T cells recognizing antigens expressed at distinct stages of Mtb infection. Copyright © 2017 Elsevier Inc. All rights reserved.

  9. Potential differentiation of islet-like cells from pregnant cow-derived placental stem cells

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    Shao-Yu Peng

    2017-06-01

    Conclusion: Altogether, islet-like cells have the potential to be differentiated from CPSCs without gene manipulation, and can be used in diabetic animal models in the future for preclinical and drug testing trial investigations.

  10. Potential differentiation of islet-like cells from pregnant cow-derived placental stem cells.

    Science.gov (United States)

    Peng, Shao-Yu; Chou, Chien-Wen; Kuo, Yu-Hsuan; Shen, Perng-Chih; Shaw, S W Steven

    2017-06-01

    Type 1 diabetes is an autoimmune disease that destroys islet cells and results in insufficient insulin secretion by pancreatic β-cells. Islet transplantation from donors is an approach used for treating patients with diabetes; however, this therapy is difficult to implement because of the lack of donors. Nevertheless, several stem cells have the potential to differentiate from islet-like cells and enable insulin secretion for treating diabetes in animal models. For example, placenta is considered a waste material and can be harvested noninvasively during delivery without ethical or moral concerns. To date, the differentiation of islet-like cells from cow-derived placental stem cells (CPSCs) has yet to be demonstrated. The investigation of potential differentiation of islet-like cells from CPSCs was conducted by supplementation with nicotinamide, exendin-4, glucose, and poly-d-lysine and was detected through reverse transcription polymerase chain reaction, dithizone staining, and immunocytochemical methods. Our results indicated that CPSCs are established and express mesenchymal stem cell surface antigen markers, such as CD73, CD166, β-integrin, and Oct-4, but not hematopoietic stem cell surface antigen markers, such as CD45. After induction, the CPSCs successfully differentiated into islet-like cells. The CPSC-derived islet-like cells expressed islet cell development-related genes, such as insulin, glucagon, pax-4, Nkx6.1, pax-6, and Fox. Moreover, CPSC-derived islet-like cells can be stained with zinc ions, which are widely distributed in the islet cells and enable insulin secretion. Altogether, islet-like cells have the potential to be differentiated from CPSCs without gene manipulation, and can be used in diabetic animal models in the future for preclinical and drug testing trial investigations. Copyright © 2017. Published by Elsevier B.V.

  11. STAT signaling in mammary gland differentiation, cell survival and tumorigenesis

    OpenAIRE

    Haricharan, S; Li, Y

    2013-01-01

    The mammary gland is a unique organ that undergoes extensive and profound changes during puberty, menstruation, pregnancy, lactation and involution. The changes that take place during puberty involve large-scale proliferation and invasion of the fat-pad. During pregnancy and lactation, the mammary cells are exposed to signaling pathways that inhibit apoptosis, induce proliferation and invoke terminal differentiation. Finally, during involution the mammary gland is exposed to milk stasis, prog...

  12. Expression of the chitinase family glycoprotein YKL-40 in undifferentiated, differentiated and trans-differentiated mesenchymal stem cells.

    Directory of Open Access Journals (Sweden)

    Daniel J Hoover

    Full Text Available The glycoprotein YKL-40 (CHI3L1 is a secreted chitinase family protein that induces angiogenesis, cell survival, and cell proliferation, and plays roles in tissue remodeling and immune regulation. It is expressed primarily in cells of mesenchymal origin, is overexpressed in numerous aggressive carcinomas and sarcomas, but is rarely expressed in normal ectodermal tissues. Bone marrow-derived mesenchymal stem cells (MSCs can be induced to differentiate into various mesenchymal tissues and trans-differentiate into some non-mesenchymal cell types. Since YKL-40 has been used as a mesenchymal marker, we followed YKL-40 expression as undifferentiated MSCs were induced to differentiate into bone, cartilage, and neural phenotypes. Undifferentiated MSCs contain significant levels of YKL-40 mRNA but do not synthesize detectable levels of YKL-40 protein. MSCs induced to differentiate into chondrocytes and osteocytes soon began to express and secrete YKL-40 protein, as do ex vivo cultured chondrocytes and primary osteocytes. In contrast, MSCs induced to trans-differentiate into neurons did not synthesize YKL-40 protein, consistent with the general absence of YKL-40 protein in normal CNS parenchyma. However, these trans-differentiated neurons retained significant levels of YKL-40 mRNA, suggesting the mechanisms which prevented YKL-40 translation in undifferentiated MSCs remained in place, and that these trans-differentiated neurons differ in at least this way from neurons derived from neuronal stem cells. Utilization of a differentiation protocol containing β-mercaptoethanol resulted in cells that expressed significant amounts of intracellular YKL-40 protein that was not secreted, which is not seen in normal cells. Thus the synthesis of YKL-40 protein is a marker for MSC differentiation into mature mesenchymal phenotypes, and the presence of untranslated YKL-40 mRNA in non-mesenchymal cells derived from MSCs reflects differences between differentiated and

  13. Differentiation within autologous fibrin scaffolds of porcine dermal cells with the mesenchymal stem cell phenotype

    International Nuclear Information System (INIS)

    Puente, Pilar de la; Ludeña, Dolores; López, Marta; Ramos, Jennifer; Iglesias, Javier

    2013-01-01

    Porcine mesenchymal stem cells (pMSCs) are an attractive source of cells for tissue engineering because their properties are similar to those of human stem cells. pMSCs can be found in different tissues but their dermal origin has not been studied in depth. Additionally, MSCs differentiation in monolayer cultures requires subcultured cells, and these cells are at risk of dedifferentiation when implanting them into living tissue. Following this, we attempted to characterize the MSCs phenotype of porcine dermal cells and to evaluate their cellular proliferation and differentiation in autologous fibrin scaffolds (AFSs). Dermal biopsies and blood samples were obtained from 12 pigs. Dermal cells were characterized by flow cytometry. Frozen autologous plasma was used to prepare AFSs. pMSC differentiation was studied in standard structures (monolayers and pellets) and in AFSs. The pMSCs expressed the CD90 and CD29 markers of the mesenchymal lineage. AFSs afforded adipogenic, osteogenic and chondrogenic differentiation. The porcine dermis can be proposed to be a good source of MSCs with adequate proliferative capacity and a suitable expression of markers. The pMSCs also showed optimal proliferation and differentiation in AFSs, such that these might serve as a promising autologous and implantable material for use in tissue engineering. -- Highlights: ► Low fibrinogen concentration provides a suitable matrix for cell migration and differentiation. ► Autologous fibrin scaffolds is a promising technique in tissue engineering. ► Dermal cells are an easily accessible mesenchymal stem cell source. ► Fibrin scaffolds afforded adipogenic, osteogenic and chondrogenic differentiation.

  14. Regulation of TFIIIB during F9 cell differentiation.

    Science.gov (United States)

    Athineos, Dimitris; Marshall, Lynne; White, Robert J

    2010-03-12

    Differentiation of F9 embryonal carcinoma (EC) cells into parietal endoderm (PE) provides a tractable model system for studying molecular events during early and inaccessible stages of murine development. PE formation is accompanied by extensive changes in gene expression both in vivo and in culture. One of the most dramatic is the ~10-fold decrease in transcriptional output by RNA polymerase (pol) III. This has been attributed to changes in activity of TFIIIB, a factor that is necessary and sufficient to recruit pol III to promoters. The goal of this study was to identify molecular changes that can account for the low activity of TFIIIB following F9 cell differentiation. Three essential subunits of TFIIIB decrease in abundance as F9 cells differentiate; these are Brf1 and Bdp1, which are pol III-specific, and TBP, which is also used by pols I and II. The decreased levels of Brf1 and Bdp1 proteins can be explained by reduced expression of the corresponding mRNAs. However, this is not the case for TBP, which is regulated post-transcriptionally. In proliferating cells, pol III transcription is stimulated by the proto-oncogene product c-Myc and the mitogen-activated protein kinase Erk, both of which bind to TFIIIB. However, c-Myc levels fall during differentiation and Erk becomes inactive through dephosphorylation. The diminished abundance of TFIIIB is therefore likely to be compounded by changes to these positive regulators that are required for its full activity. In addition, PE cells have elevated levels of the retinoblastoma protein RB, which is known to bind and repress TFIIIB. The low activity of TFIIIB in PE can be attributed to a combination of changes, any one of which could be sufficient to inhibit pol III transcription. Declining levels of essential TFIIIB subunits and of activators that are required for maximal TFIIIB activity are accompanied by an increase in a potent repressor of TFIIIB. These events provide fail-safe guarantees to ensure that pol III

  15. Simplified Dynamic Analysis of Grinders Spindle Node

    Science.gov (United States)

    Demec, Peter

    2014-12-01

    The contribution deals with the simplified dynamic analysis of surface grinding machine spindle node. Dynamic analysis is based on the use of the transfer matrix method, which is essentially a matrix form of method of initial parameters. The advantage of the described method, despite the seemingly complex mathematical apparatus, is primarily, that it does not require for solve the problem of costly commercial software using finite element method. All calculations can be made for example in MS Excel, which is advantageous especially in the initial stages of constructing of spindle node for the rapid assessment of the suitability its design. After detailing the entire structure of spindle node is then also necessary to perform the refined dynamic analysis in the environment of FEM, which it requires the necessary skills and experience and it is therefore economically difficult. This work was developed within grant project KEGA No. 023TUKE-4/2012 Creation of a comprehensive educational - teaching material for the article Production technique using a combination of traditional and modern information technology and e-learning.

  16. Material Choice for spindle of machine tools

    Science.gov (United States)

    Gouasmi, S.; Merzoug, B.; Abba, G.; Kherredine, L.

    2012-02-01

    The requirements of contemporary industry and the flashing development of modern sciences impose restrictions on the majority of the elements of machines; the resulting financial constraints can be satisfied by a better output of the production equipment. As for those concerning the design, the resistance and the correct operation of the product, these require the development of increasingly precise parts, therefore the use of increasingly powerful tools [5]. The precision of machining and the output of the machine tools are generally determined by the precision of rotation of the spindle, indeed, more this one is large more the dimensions to obtain are in the zone of tolerance and the defects of shape are minimized. During the development of the machine tool, the spindle which by definition is a rotating shaft receiving and transmitting to the work piece or the cutting tool the rotational movement, must be designed according to certain optimal parameters to be able to ensure the precision required. This study will be devoted to the choice of the material of the spindle fulfilling the imposed requirements of precision.

  17. Material Choice for spindle of machine tools

    International Nuclear Information System (INIS)

    Gouasmi, S; Merzoug, B; Kherredine, L; Abba, G

    2012-01-01

    The requirements of contemporary industry and the flashing development of modern sciences impose restrictions on the majority of the elements of machines; the resulting financial constraints can be satisfied by a better output of the production equipment. As for those concerning the design, the resistance and the correct operation of the product, these require the development of increasingly precise parts, therefore the use of increasingly powerful tools [5]. The precision of machining and the output of the machine tools are generally determined by the precision of rotation of the spindle, indeed, more this one is large more the dimensions to obtain are in the zone of tolerance and the defects of shape are minimized. During the development of the machine tool, the spindle which by definition is a rotating shaft receiving and transmitting to the work piece or the cutting tool the rotational movement, must be designed according to certain optimal parameters to be able to ensure the precision required. This study will be devoted to the choice of the material of the spindle fulfilling the imposed requirements of precision.

  18. Carbon nanopillars for enhanced stem cell differentiation and dopamine detection

    DEFF Research Database (Denmark)

    Bunea, Ada-Ioana; Amato, Letizia; Valsesia, Andrea

    of human neural stem cells (hNSCs) into dopaminergic neurons and that they can also be employed for detecting dopamine release from mature neurons attached to them [1]. Here, we report 3D carbon nanopillars, fabricated through colloidal lithography, with even more pronounced effect on the electrochemical......Parkinson’s disease is characterized by a deficit of dopamine in the brain, a neurotransmitter involved in the motor function. One of the future ideas for treatment is cell replacement therapy. Our group has previously shown that pyrolysed 3D carbon micropillars induce spontaneous differentiation...

  19. Survey of Differentially Methylated Promoters in Prostate Cancer Cell Lines

    Directory of Open Access Journals (Sweden)

    Yipeng Wang

    2005-08-01

    Full Text Available DNA methylation, copy number in the genomes of three immortalized prostate epithelial, five cancer cell lines (LNCaP, PC3, PC3M, PC3M-Pro4, PC3MLN4 were compared using a microarray-based technique. Genomic DNA is cut with a methylation-sensitive enzyme Hpall, followed by linker ligation, polymerase chain reaction (PCR amplification, labeling, hybridization to an array of promoter sequences. Only those parts of the genomic DNA that have unmethylated restriction sites within a few hundred base pairs generate PCR products detectable on an array. Of 2732 promoter sequences on a test array, 504 (18.5% showed differential hybridization between immortalized prostate epithelial, cancer cell lines. Among candidate hypermethylated genes in cancer-derived lines, there were eight (CD44, CDKN1A, ESR1, PLAU, RARB, SFN, TNFRSF6, TSPY previously observed in prostate cancer, 13 previously known methylation targets in other cancers (ARHI, bcl-2, BRCA1, CDKN2C, GADD45A, MTAP, PGR, SLC26A4, SPARC, SYK, TJP2, UCHL1, WIT-1. The majority of genes that appear to be both differentially methylated, differentially regulated between prostate epithelial, cancer cell lines are novel methylation targets, including PAK6, RAD50, TLX3, PIR51, MAP2K5, INSR, FBN1, GG2-1, representing a rich new source of candidate genes used to study the role of DNA methylation in prostate tumors.

  20. Differentiation of Human Dental Pulp Stem Cells into Dopaminergic Neuron-like Cells in Vitro.

    Science.gov (United States)

    Chun, So Young; Soker, Shay; Jang, Yu-Jin; Kwon, Tae Gyun; Yoo, Eun Sang

    2016-02-01

    We investigated the potential of human dental pulp stem cells (hDPSCs) to differentiate into dopaminergic neurons in vitro as an autologous stem cell source for Parkinson's disease treatment. The hDPSCs were expanded in knockout-embryonic stem cell (KO-ES) medium containing leukemia inhibitory factor (LIF) on gelatin-coated plates for 3-4 days. Then, the medium was replaced with KO-ES medium without LIF to allow the formation of the neurosphere for 4 days. The neurosphere was transferred into ITS medium, containing ITS (human insulin-transferrin-sodium) and fibronectin, to select for Nestin-positive cells for 6-8 days. The cells were then cultured in N-2 medium containing basic fibroblast growth factor (FGF), FGF-8b, sonic hedgehog-N, and ascorbic acid on poly-l-ornithine/fibronectin-coated plates to expand the Nestin-positive cells for up to 2 weeks. Finally, the cells were transferred into N-2/ascorbic acid medium to allow for their differentiation into dopaminergic neurons for 10-15 days. The differentiation stages were confirmed by morphological, immunocytochemical, flow cytometric, real-time PCR, and ELISA analyses. The expressions of mesenchymal stem cell markers were observed at the early stages. The expressions of early neuronal markers were maintained throughout the differentiation stages. The mature neural markers showed increased expression from stage 3 onwards. The percentage of cells positive for tyrosine hydroxylase was 14.49%, and the amount was 0.526 ± 0.033 ng/mL at the last stage. hDPSCs can differentiate into dopaminergic neural cells under experimental cell differentiation conditions, showing potential as an autologous cell source for the treatment of Parkinson's disease.

  1. Sleep spindles and intelligence: evidence for a sexual dimorphism.

    Science.gov (United States)

    Ujma, Péter P; Konrad, Boris Nikolai; Genzel, Lisa; Bleifuss, Annabell; Simor, Péter; Pótári, Adrián; Körmendi, János; Gombos, Ferenc; Steiger, Axel; Bódizs, Róbert; Dresler, Martin

    2014-12-03

    Sleep spindles are thalamocortical oscillations in nonrapid eye movement sleep, which play an important role in sleep-related neuroplasticity and offline information processing. Sleep spindle features are stable within and vary between individuals, with, for example, females having a higher number of spindles and higher spindle density than males. Sleep spindles have been associated with learning potential and intelligence; however, the details of this relationship have not been fully clarified yet. In a sample of 160 adult human subjects with a broad IQ range, we investigated the relationship between sleep spindle parameters and intelligence. In females, we found a positive age-corrected association between intelligence and fast sleep spindle amplitude in central and frontal derivations and a positive association between intelligence and slow sleep spindle duration in all except one derivation. In males, a negative association between intelligence and fast spindle density in posterior regions was found. Effects were continuous over the entire IQ range. Our results demonstrate that, although there is an association between sleep spindle parameters and intellectual performance, these effects are more modest than previously reported and mainly present in females. This supports the view that intelligence does not rely on a single neural framework, and stronger neural connectivity manifesting in increased thalamocortical oscillations in sleep is one particular mechanism typical for females but not males. Copyright © 2014 the authors 0270-6474/14/3416358-11$15.00/0.

  2. Dishevelled binds the Discs large 'Hook' domain to activate GukHolder-dependent spindle positioning in Drosophila.

    Directory of Open Access Journals (Sweden)

    Joshua D Garcia

    Full Text Available Communication between cortical cell polarity cues and the mitotic spindle ensures proper orientation of cell divisions within complex tissues. Defects in mitotic spindle positioning have been linked to various developmental disorders and have recently emerged as a potential contributor to tumorigenesis. Despite the importance of this process to human health, the molecular mechanisms that regulate spindle orientation are not fully understood. Moreover, it remains unclear how diverse cortical polarity complexes might cooperate to influence spindle positioning. We and others have demonstrated spindle orientation roles for Dishevelled (Dsh, a key regulator of planar cell polarity, and Discs large (Dlg, a conserved apico-basal cell polarity regulator, effects which were previously thought to operate within distinct molecular pathways. Here we identify a novel direct interaction between the Dsh-PDZ domain and the alternatively spliced "I3-insert" of the Dlg-Hook domain, thus establishing a potential convergent Dsh/Dlg pathway. Furthermore, we identify a Dlg sequence motif necessary for the Dsh interaction that shares homology to the site of Dsh binding in the Frizzled receptor. Expression of Dsh enhanced Dlg-mediated spindle positioning similar to deletion of the Hook domain. This Dsh-mediated activation was dependent on the Dlg-binding partner, GukHolder (GukH. These results suggest that Dsh binding may regulate core interdomain conformational dynamics previously described for Dlg. Together, our results identify Dlg as an effector of Dsh signaling and demonstrate a Dsh-mediated mechanism for the activation of Dlg/GukH-dependent spindle positioning. Cooperation between these two evolutionarily-conserved cell polarity pathways could have important implications to both the development and maintenance of tissue homeostasis in animals.

  3. Differentiation of Equine Mesenchymal Stromal Cells into Cells of Neural Lineage: Potential for Clinical Applications

    Directory of Open Access Journals (Sweden)

    Claudia Cruz Villagrán

    2014-01-01

    Full Text Available Mesenchymal stromal cells (MSCs are able to differentiate into extramesodermal lineages, including neurons. Positive outcomes were obtained after transplantation of neurally induced MSCs in laboratory animals after nerve injury, but this is unknown in horses. Our objectives were to test the ability of equine MSCs to differentiate into cells of neural lineage in vitro, to assess differences in morphology and lineage-specific protein expression, and to investigate if horse age and cell passage number affected the ability to achieve differentiation. Bone marrow-derived MSCs were obtained from young and adult horses. Following demonstration of stemness, MSCs were neurally induced and microscopically assessed at different time points. Results showed that commercially available nitrogen-coated tissue culture plates supported proliferation and differentiation. Morphological changes were immediate and all the cells displayed a neural crest-like cell phenotype. Expression of neural progenitor proteins, was assessed via western blot or immunofluorescence. In our study, MSCs generated from young and middle-aged horses did not show differences in their ability to undergo differentiation. The effect of cell passage number, however, is inconsistent and further experiments are needed. Ongoing work is aimed at transdifferentiating these cells into Schwann cells for transplantation into a peripheral nerve injury model in horses.

  4. Potential of bursa-immigrated hematopoietic precursor cells to differentiate to functional B and T cells

    International Nuclear Information System (INIS)

    Weber, W.T.; Alexander, J.E.

    1978-01-01

    The potential of hematopoietic precursor cells, recently immigrated into the 13- and 14-day-old embryonic bursa, to migrate to the thymus and to differentiate to functional T cells was investigated. Chromosomally marked cell populations obtained from 13- and 14-day-old embryonic bursas were transferred i.v. to 780 R γ-irradiated chick embryos of equivalent age. When appropriate chimeras were examined at 4 to 12 weeks after cell transfer, donor cells were found to proliferate primarily in the bursa. Significant donor cell influx into the thymus was not detected. In correlation with these findings, Con A- and PHA-responsive T cells in thymus and spleen cell cultures of recipients remained of host origin whereas the number of anti-CIg responsive B cells of donor type increased gradually in the spleens of recipients. An initial lag period preceded the accumulation of functional donor B cells in the spleens of recipients, despite the predominant presence of dividing donor cells in the bursa. This suggests that the transferred bursal cell population required substantially longer to mature and emigrate from the bursa as functional B cells than the host cell population remaining in the irradiated bursas at time of cell transfer. The failure to detect significant influx of donor cells into the thymus and their failure to differentiate to functional T cells suggest that the recently bursa-immigrated hematopoietic stem cells of 13- and 14-day-old embryos may not be pluripotential cells, but rather cells already committed to the B cell line of differentiation

  5. Glutathione S-transferase expression and isoenzyme composition during cell differentiation of Caco-2 cells

    International Nuclear Information System (INIS)

    Scharmach, E.; Hessel, S.; Niemann, B.; Lampen, A.

    2009-01-01

    The human colon adenocarcinoma cell line Caco-2 is frequently used to study human intestinal metabolism and transport of xenobiotica. Previous studies have shown that both Caco-2 cells and human colon cells constitutively express the multigene family of detoxifying enzymes glutathione S-transferases (GSTs), particularly GST alpha and GST pi. GSTs may play a fundamental role in the molecular interplay between phase I, II enzymes and ABC-transporters. The gut fermentation product, butyrate, can modulate the potential for detoxification. The aim of this study was to investigate the basal expression of further cytosolic GSTs in Caco-2 cells during cell differentiation. In addition, a comparison was made with expression levels in MCF-7 and HepG2, two other cell types with barrier functions. Finally, the butyrate-mediated modulation of gene and protein expression was determined by real time PCR and western blot analysis. In Caco-2, gene and protein expression levels of GST alpha increased during cell differentiation. High levels of GSTO1 and GSTP1 were constantly expressed. No expression of GSTM5 and GSTT1 was detected. HepG2 expressed GSTO1 and MCF-7 GSTZ1 most intensively. No expression of GSTA5, GSTM5, or GSTP1 was detected in either cell. Incubation of Caco-2 cells with butyrate (5 mM) significantly induced GSTA1 and GSTM2 in proliferating Caco-2 cells. In differentiated cells, butyrate tended to increase GSTO1 and GSTP1. The results of this study show that a differentiation-dependent expression of GSTs in Caco-2 cells may reflect the in vivo situation and indicate the potential of butyrate to modify intestinal metabolism. GSTA1-A4 have been identified as good markers for cell differentiation. The Caco-2 cell line is a useful model for assessing the potential of food-related substances to modulate the GST expression pattern.

  6. Glutathione S-transferase expression and isoenzyme composition during cell differentiation of Caco-2 cells.

    Science.gov (United States)

    Scharmach, E; Hessel, S; Niemann, B; Lampen, A

    2009-11-30

    The human colon adenocarcinoma cell line Caco-2 is frequently used to study human intestinal metabolism and transport of xenobiotica. Previous studies have shown that both Caco-2 cells and human colon cells constitutively express the multigene family of detoxifying enzymes glutathione S-transferases (GSTs), particularly GST alpha and GST pi. GSTs may play a fundamental role in the molecular interplay between phase I, II enzymes and ABC-transporters. The gut fermentation product, butyrate, can modulate the potential for detoxification. The aim of this study was to investigate the basal expression of further cytosolic GSTs in Caco-2 cells during cell differentiation. In addition, a comparison was made with expression levels in MCF-7 and HepG2, two other cell types with barrier functions. Finally, the butyrate-mediated modulation of gene and protein expression was determined by real time PCR and western blot analysis. In Caco-2, gene and protein expression levels of GST alpha increased during cell differentiation. High levels of GSTO1 and GSTP1 were constantly expressed. No expression of GSTM5 and GSTT1 was detected. HepG2 expressed GSTO1 and MCF-7 GSTZ1 most intensively. No expression of GSTA5, GSTM5, or GSTP1 was detected in either cell. Incubation of Caco-2 cells with butyrate (5 mM) significantly induced GSTA1 and GSTM2 in proliferating Caco-2 cells. In differentiated cells, butyrate tended to increase GSTO1 and GSTP1. The results of this study show that a differentiation-dependent expression of GSTs in Caco-2 cells may reflect the in vivo situation and indicate the potential of butyrate to modify intestinal metabolism. GSTA1-A4 have been identified as good markers for cell differentiation. The Caco-2 cell line is a useful model for assessing the potential of food-related substances to modulate the GST expression pattern.

  7. Epigenetics of peripheral B cell differentiation and the antibody response

    Directory of Open Access Journals (Sweden)

    Hong eZan

    2015-12-01

    Full Text Available Epigenetic modifications, such as histone post-translational modifications, DNA methylation, and alteration of gene expression by non-coding RNAs, including microRNAs (miRNAs and long non-coding RNAs (lncRNAs, are heritable changes that are independent from the genomic DNA sequence. These regulate gene activities and, therefore, cellular functions. Epigenetic modifications act in concert with transcription factors and play critical roles in B cell development and differentiation, thereby modulating antibody responses to foreign- and self-antigens. Upon antigen encounter by mature B cells in the periphery, alterations of these lymphocytes epigenetic landscape are induced by the same stimuli that drive the antibody response. Such alterations instruct B cells to undergo immunoglobulin class switch DNA recombination (CSR and somatic hypermutation (SHM, as well as differentiation to memory B cells or long-lived plasma cells for the immune memory. Inducible histone modifications, together with DNA methylation and miRNAs modulate the transcriptome, particularly the expression of activation-induced cytidine deaminase (AID, which is essential for CSR and SHM, and factors central to plasma cell differentiation, such as B lymphocyte-induced maturation protein-1 (Blimp-1. These inducible B cell-intrinsic epigenetic marks guide the maturation of antibody responses. Combinatorial histone modifications also function as histone codes to target CSR and, possibly, SHM machinery to the Ig loci by recruiting specific adaptors that can stabilize CSR/SHM factors. In addition, lncRNAs, such as recently reported lncRNA-CSR and an lncRNA generated through transcription of the S region that form G-quadruplex structures, are also important for CSR targeting. Epigenetic dysregulation in B cells, including the aberrant expression of non-coding RNAs and alterations of histone modifications and DNA methylation, can result in aberrant antibody responses to foreign antigens

  8. Differentiation of neural crest stem cells from nasal mucosa into motor neuron-like cells.

    Science.gov (United States)

    Bagher, Zohreh; Kamrava, Seyed Kamran; Alizadeh, Rafieh; Farhadi, Mohammad; Absalan, Moloud; Falah, Masoumeh; Faghihi, Faezeh; Zare-Sadeghi, Arash; Komeili, Ali

    2018-05-25

    Cell transplantation is a potential therapeutic approach for repairing neuropathological and neurodegenerative disorders of central nervous system by replacing the degenerated cells with new ones. Among a variety of stem cell candidates to provide these new cells, olfactory ectomesenchymal stem cells (OE-MSCs) have attracted a great attention due to their neural crest origin, easy harvest, high proliferation, and autologous transplantation. Since there is no report on differentiation potential of these cells into motor neuron-like cells, we evaluated this potential using Real-time PCR, flowcytometry and immunocytochemistry after the treatment with differentiation cocktail containing retinoic acid and Sonic Hedgehog. Immunocytochemistry staining of the isolated OE-MSCs demonstrated their capability to express nestin and vimentin, as the two markers of primitive neuroectoderm. The motor neuron differentiation of OE-MSCs resulted in changing their morphology into bipolar cells with high expression of motor neuron markers of ChAT, Hb-9 and Islet-1 at the level of mRNA and protein. Consequently, we believe that the OE-MSCs have great potential to differentiate into motor neuron-like cells and can be an ideal stem cell source for the treatment of motor neuron-related disorders of central nervous system. Copyright © 2018 Elsevier B.V. All rights reserved.

  9. Lymphoma and the control of B cell growth and differentiation.

    Science.gov (United States)

    Rui, Lixin; Goodnow, Christopher C

    2006-05-01

    It is now widely accepted that lymphomagenesis is a multistep transformation process. A number of genetic changes and environmental and infectious factors contributing to the development and malignant progression of B-cell lymphoproliferative disorders are well documented. Reciprocal chromosomal translocations involving the immunoglobulin loci are a hallmark of most mature B cell lymphomas and lead to dysregulated expression of proto-oncogenes (c-myc) important for cell proliferation or genes involved in cell cycle progression (cyclin D1), differentiation block (bcl-6, PAX5) and cell survival (bcl-2, NF-kappaB). In addition, genetic alterations that inactivate tumor suppressor genes (p53, p16) have been frequently detected in some lymphoma tissues. Many of these genes are normally regulated by signals from the B cell antigen receptor. The high prevalence of bacterial and viral infection in lymphoma patients supports the hypothesis that infectious agents may play a contributory role in the development and evolution of B cell lymphoproliferative disorders by either directly inducing polyclonal B cell hyperactivation (EBV, HCV), or providing a chronic antigenic stimulus (EBV, HCV, HBV, H. pylori), or mimicking B cell antigen receptor signaling (EBV, HCV, HHV8), although whether these are causative factors or they are secondary to genetic changes in lymphomagenesis remains to be defined. Stimulatory signals from reactive T cells, local cytokines and growth factors can also contribute, to some extent, to the progression of transformation. Modulation of B cell antigen receptor signaling therefore emerges as a potentially powerful strategy for controlling the growth of certain B cell lymphomas.

  10. Stem cell therapy. Use of differentiated pluripotent stem cells as replacement therapy for treating disease

    DEFF Research Database (Denmark)

    Fox, Ira J; Daley, George Q; Goldman, Steven A

    2014-01-01

    Pluripotent stem cells (PSCs) directed to various cell fates holds promise as source material for treating numerous disorders. The availability of precisely differentiated PSC-derived cells will dramatically affect blood component and hematopoietic stem cell therapies and should facilitate......, and industry is critical for generating new stem cell-based therapies....... treatment of diabetes, some forms of liver disease and neurologic disorders, retinal diseases, and possibly heart disease. Although an unlimited supply of specific cell types is needed, other barriers must be overcome. This review of the state of cell therapies highlights important challenges. Successful...

  11. Prion protein expression regulates embryonic stem cell pluripotency and differentiation.

    Directory of Open Access Journals (Sweden)

    Alberto Miranda

    2011-04-01

    Full Text Available Cellular prion protein (PRNP is a glycoprotein involved in the pathogenesis of transmissible spongiform encephalopathies (TSEs. Although the physiological function of PRNP is largely unknown, its key role in prion infection has been extensively documented. This study examines the functionality of PRNP during the course of embryoid body (EB differentiation in mouse Prnp-null (KO and WT embryonic stem cell (ESC lines. The first feature observed was a new population of EBs that only appeared in the KO line after 5 days of differentiation. These EBs were characterized by their expression of several primordial germ cell (PGC markers until Day 13. In a comparative mRNA expression analysis of genes playing an important developmental role during ESC differentiation to EBs, Prnp was found to participate in the transcription of a key pluripotency marker such as Nanog. A clear switching off of this gene on Day 5 was observed in the KO line as opposed to the WT line, in which maximum Prnp and Nanog mRNA levels appeared at this time. Using a specific antibody against PRNP to block PRNP pathways, reduced Nanog expression was confirmed in the WT line. In addition, antibody-mediated inhibition of ITGB5 (integrin αvβ5 in the KO line rescued the low expression of Nanog on Day 5, suggesting the regulation of Nanog transcription by Prnp via this Itgb5. mRNA expression analysis of the PRNP-related proteins PRND (Doppel and SPRN (Shadoo, whose PRNP function is known to be redundant, revealed their incapacity to compensate for the absence of PRNP during early ESC differentiation. Our findings provide strong evidence for a relationship between Prnp and several key pluripotency genes and attribute Prnp a crucial role in regulating self-renewal/differentiation status of ESC, confirming the participation of PRNP during early embryogenesis.

  12. Phospho-Bcl-xL(Ser62) influences spindle assembly and chromosome segregation during mitosis.

    Science.gov (United States)

    Wang, Jianfang; Beauchemin, Myriam; Bertrand, Richard

    2014-01-01

    Functional analysis of a series of phosphorylation mutants reveals that Bcl-xL(Ser62Ala) influences cell entry into anaphase and mitotic exit in taxol-exposed cells compared with cells expressing wild-type Bcl-xL or a series of other phosphorylation mutants, an effect that appears to be independent of its anti-apoptotic activity. During normal mitosis progression, Bcl-xL(Ser62) is strongly phosphorylated by PLK1 and MAPK14/SAPKp38α at the prometaphase, metaphase, and the anaphase boundaries, while it is de-phosphorylated at telophase and cytokinesis. Phospho-Bcl-xL(Ser62) localizes in centrosomes with γ-tubulin and in the mitotic cytosol with some spindle-assembly checkpoint signaling components, including PLK1, BubR1, and Mad2. In taxol- and nocodazole-exposed cells, phospho-Bcl-xL(Ser62) also binds to Cdc20- Mad2-, BubR1-, and Bub3-bound complexes, while Bcl-xL(Ser62Ala) does not. Silencing Bcl-xL expression and expressing the phosphorylation mutant Bcl-xL(Ser62Ala) lead to an increased number of cells harboring mitotic spindle defects including multipolar spindle, chromosome lagging and bridging, aneuploidy with micro-, bi-, or multi-nucleated cells, and cells that fail to resolve undergo mitosis within 6 h. Together, the data indicate that during mitosis, Bcl-xL(Ser62) phosphorylation impacts on spindle assembly and chromosome segregation, influencing chromosome stability. Observations of mitotic cells harboring aneuploidy with micro-, bi-, or multi-nucleated cells, and cells that fail to resolve undergo mitosis within 6 h were also made with cells expressing the phosphorylation mutant Bcl-xL(Ser49Ala) and dual mutant Bcl-xL(Ser49/62Ala).

  13. Zfp206 regulates ES cell gene expression and differentiation.

    Science.gov (United States)

    Zhang, Wen; Walker, Emily; Tamplin, Owen J; Rossant, Janet; Stanford, William L; Hughes, Timothy R

    2006-01-01

    Understanding transcriptional regulation in early developmental stages is fundamental to understanding mammalian development and embryonic stem (ES) cell properties. Expression surveys suggest that the putative SCAN-Zinc finger transcription factor Zfp206 is expressed specifically in ES cells [Zhang,W., Morris,Q.D., Chang,R., Shai,O., Bakowski,M.A., Mitsakakis,N., Mohammad,N., Robinson,M.D., Zirngibl,R., Somogyi,E. et al., (2004) J. Biol., 3, 21; Brandenberger,R., Wei,H., Zhang,S., Lei,S., Murage,J., Fisk,G.J., Li,Y., Xu,C., Fang,R., Guegler,K. et al., (2004) Nat. Biotechnol., 22, 707-716]. Here, we confirm this observation, and we show that ZFP206 expression decreases rapidly upon differentiation of cultured mouse ES cells, and during development of mouse embryos. We find that there are at least six isoforms of the ZFP206 transcript, the longest being predominant. Overexpression and depletion experiments show that Zfp206 promotes formation of undifferentiated ES cell clones, and positively regulates abundance of a very small set of transcripts whose expression is also specific to ES cells and the two- to four-cell stages of preimplantation embryos. This set includes members of the Zscan4, Thoc4, Tcstv1 and eIF-1A gene families, none of which have been functionally characterized in vivo but whose members include apparent transcription factors, RNA-binding proteins and translation factors. Together, these data indicate that Zfp206 is a regulator of ES cell differentiation that controls a set of genes expressed very early in development, most of which themselves appear to be regulators.

  14. Bone marrow mesenchymal stem cells stimulate proliferation and neuronal differentiation of retinal progenitor cells.

    Directory of Open Access Journals (Sweden)

    Jing Xia

    Full Text Available During retina development, retinal progenitor cell (RPC proliferation and differentiation are regulated by complex inter- and intracellular interactions. Bone marrow mesenchymal stem cells (BMSCs are reported to express a variety of cytokines and neurotrophic factors, which have powerful trophic and protective functions for neural tissue-derived cells. Here, we show that the expanded RPC cultures treated with BMSC-derived conditioned medium (CM which was substantially enriched for bFGF and CNTF, expressed clearly increased levels of nuclear receptor TLX, an essential regulator of neural stem cell (NSC self-renewal, as well as betacellulin (BTC, an EGF-like protein described as supporting NSC expansion. The BMSC CM- or bFGF-treated RPCs also displayed an obviously enhanced proliferation capability, while BMSC CM-derived bFGF knocked down by anti-bFGF, the effect of BMSC CM on enhancing RPC proliferation was partly reversed. Under differentiation conditions, treatment with BMSC CM or CNTF markedly favoured RPC differentiation towards retinal neurons, including Brn3a-positive retinal ganglion cells (RGCs and rhodopsin-positive photoreceptors, and clearly diminished retinal glial cell differentiation. These findings demonstrate that BMSCs supported RPC proliferation and neuronal differentiation which may be partly mediated by BMSC CM-derived bFGF and CNTF, reveal potential limitations of RPC culture systems, and suggest a means for optimizing RPC cell fate determination in vitro.

  15. Tumor necrosis factor (cachetin) decreases adipose cell differentiation in primary cell culture

    International Nuclear Information System (INIS)

    Martin, R.J.; Jones, D.D.; Jewell, D.E.; Hausman, G.J.

    1986-01-01

    Cachetin has been shown to effect gene product expression in the established adipose cell line 3T3-L1. Expression of messenger RNA for lipoprotein lipase is suppressed in cultured adipocytes. The purpose of this study was to determine the effect of Cachetin on adipose cell differentiation in primary cell culture. Stromalvascular cells obtained from the inguinal fat pad of 4-5 week old Sprague-Dawley rats were grown in culture for two weeks. During the proliferative growth phase all cells were grown on the same medium and labelled with 3 H-thymidine. Cachetin treatment (10 -6 to 10 -10 M) was initiated on day 5, the initial phase of preadipocyte differentiation. Adipocytes and stromal cells were separated using density gradient, and 3 H-thymidine was determined for both cell types. Thymidine incorporation into adipose cells was decreased maximally (∼ 50%) at 10 -10 M. Stromalvascular cells were not influenced at any of the doses tested. Adipose cell lipid content as indicated by oil red-O staining was decreased by Cachetin. Esterase staining by adipose cells treated with Cachetin was increased indicating an increase in intracellular lipase. These studies show that Cachetin has specific effects on primary adipose cell differentiation

  16. Single-cell RNA sequencing reveals metallothionein heterogeneity during hESC differentiation to definitive endoderm

    Directory of Open Access Journals (Sweden)

    Junjie Lu

    2018-04-01

    Full Text Available Differentiation of human pluripotent stem cells towards definitive endoderm (DE is the critical first step for generating cells comprising organs such as the gut, liver, pancreas and lung. This in-vitro differentiation process generates a heterogeneous population with a proportion of cells failing to differentiate properly and maintaining expression of pluripotency factors such as Oct4. RNA sequencing of single cells collected at four time points during a 4-day DE differentiation identified high expression of metallothionein genes in the residual Oct4-positive cells that failed to differentiate to DE. Using X-ray fluorescence microscopy and multi-isotope mass spectrometry, we discovered that high intracellular zinc level corresponds with persistent Oct4 expression and failure to differentiate. This study improves our understanding of the cellular heterogeneity during in-vitro directed differentiation and provides a valuable resource to improve DE differentiation efficiency. Keywords: hPSC, Differentiation, Definitive endoderm, Heterogeneity, Single cell, RNA sequencing

  17. Decoding cell signalling and regulation of oligodendrocyte differentiation.

    Science.gov (United States)

    Santos, A K; Vieira, M S; Vasconcellos, R; Goulart, V A M; Kihara, A H; Resende, R R

    2018-05-22

    Oligodendrocytes are fundamental for the functioning of the nervous system; they participate in several cellular processes, including axonal myelination and metabolic maintenance for astrocytes and neurons. In the mammalian nervous system, they are produced through waves of proliferation and differentiation, which occur during embryogenesis. However, oligodendrocytes and their precursors continue to be generated during adulthood from specific niches of stem cells that were not recruited during development. Deficiencies in the formation and maturation of these cells can generate pathologies mainly related to myelination. Understanding the mechanisms involved in oligodendrocyte development, from the precursor to mature cell level, will allow inferring therapies and treatments for associated pathologies and disorders. Such mechanisms include cell signalling pathways that involve many growth factors, small metabolic molecules, non-coding RNAs, and transcription factors, as well as specific elements of the extracellular matrix, which act in a coordinated temporal and spatial manner according to a given stimulus. Deciphering those aspects will allow researchers to replicate them in vitro in a controlled environment and thus mimic oligodendrocyte maturation to understand the role of oligodendrocytes in myelination in pathologies and normal conditions. In this study, we review these aspects, based on the most recent in vivo and in vitro data on oligodendrocyte generation and differentiation. Copyright © 2018 Elsevier Ltd. All rights reserved.

  18. STAT signaling in mammary gland differentiation, cell survival and tumorigenesis.

    Science.gov (United States)

    Haricharan, S; Li, Y

    2014-01-25

    The mammary gland is a unique organ that undergoes extensive and profound changes during puberty, menstruation, pregnancy, lactation and involution. The changes that take place during puberty involve large-scale proliferation and invasion of the fat-pad. During pregnancy and lactation, the mammary cells are exposed to signaling pathways that inhibit apoptosis, induce proliferation and invoke terminal differentiation. Finally, during involution the mammary gland is exposed to milk stasis, programmed cell death and stromal reorganization to clear the differentiated milk-producing cells. Not surprisingly, the signaling pathways responsible for bringing about these changes in breast cells are often subverted during the process of tumorigenesis. The STAT family of proteins is involved in every stage of mammary gland development, and is also frequently implicated in breast tumorigenesis. While the roles of STAT3 and STAT5 during mammary gland development and tumorigenesis are well studied, others members, e.g. STAT1 and STAT6, have only recently been observed to play a role in mammary gland biology. Continued investigation into the STAT protein network in the mammary gland will likely yield new biomarkers and risk factors for breast cancer, and may also lead to novel prophylactic or therapeutic strategies against breast cancer. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  19. Direct Differentiation of Human Pluripotent Stem Cells into Haploid Spermatogenic Cells

    Directory of Open Access Journals (Sweden)

    Charles A. Easley, IV

    2012-09-01

    Full Text Available Human embryonic stem cells (hESCs and induced pluripotent stem cells (hiPSCs have been shown to differentiate into primordial germ cells (PGCs but not into spermatogonia, haploid spermatocytes, or spermatids. Here, we show that hESCs and hiPSCs differentiate directly into advanced male germ cell lineages, including postmeiotic, spermatid-like cells, in vitro without genetic manipulation. Furthermore, our procedure mirrors spermatogenesis in vivo by differentiating PSCs into UTF1-, PLZF-, and CDH1-positive spermatogonia-like cells; HIWI- and HILI-positive spermatocyte-like cells; and haploid cells expressing acrosin, transition protein 1, and protamine 1 (proteins that are uniquely found in spermatids and/or sperm. These spermatids show uniparental genomic imprints similar to those of human sperm on two loci: H19 and IGF2. These results demonstrate that male PSCs have the ability to differentiate directly into advanced germ cell lineages and may represent a novel strategy for studying spermatogenesis in vitro.

  20. In vitro differentiation of neural cells from human adipose tissue derived stromal cells.

    Science.gov (United States)

    Dave, Shruti D; Patel, Chetan N; Vanikar, Aruna V; Trivedi, Hargovind L

    2018-01-01

    Stem cells, including neural stem cells (NSCs), are endowed with self-renewal capability and hence hold great opportunity for the institution of replacement/protective therapy. We propose a method for in vitro generation of stromal cells from human adipose tissue and their differentiation into neural cells. Ten grams of donor adipose tissue was surgically resected from the abdominal wall of the human donor after the participants' informed consents. The resected adipose tissue was minced and incubated for 1 hour in the presence of an enzyme (collagenase-type I) at 37 0 C followed by its centrifugation. After centrifugation, the supernatant and pellets were separated and cultured in a medium for proliferation at 37 0 C with 5% CO2 for 9-10 days in separate tissue culture dishes for generation of mesenchymal stromal cells (MSC). At the end of the culture, MSC were harvested and analyzed. The harvested MSC were subjected for further culture for their differentiation into neural cells for 5-7 days using differentiation medium mainly comprising of neurobasal medium. At the end of the procedure, culture cells were isolated and studied for expression of transcriptional factor proteins: orthodenticle homolog-2 (OTX-2), beta-III-tubulin (β3-Tubulin), glial-fibrillary acid protein (GFAP) and synaptophysin-β2. In total, 50 neural cells-lines were generated. In vitro generated MSC differentiated neural cells' mean quantum was 5.4 ± 6.9 ml with the mean cell count being, 5.27 ± 2.65 × 10 3/ μl. All of them showed the presence of OTX-2, β3-Tubulin, GFAP, synaptophysin-β2. Neural cells can be differentiated in vitro from MSC safely and effectively. In vitro generated neural cells represent a potential therapy for recovery from spinal cord injuries and neurodegenerative disease.

  1. Targeting sarcoma tumor-initiating cells through differentiation therapy

    Directory of Open Access Journals (Sweden)

    Dan Han

    2017-05-01

    Full Text Available Human leukocyte antigen class I (HLA-I down-regulation has been reported in many human cancers to be associated with poor clinical outcome. However, its connection to tumor-initiating cells (TICs remains unknown. In this study, we report that HLA-I is down-regulated in a subpopulation of cells that have high tumor initiating capacity in different types of human sarcomas. Detailed characterization revealed their distinct molecular profiles regarding proliferation, apoptosis and stemness programs. Notably, these TICs can be induced to differentiate along distinct mesenchymal lineages, including the osteogenic pathway. The retinoic acid receptor signaling pathway is overexpressed in HLA-1 negative TICs. All-trans retinoic acid treatment successfully induced osteogenic differentiation of this subpopulation, in vitro and in vivo, resulting in significantly decreased tumor formation. Thus, our findings indicate down-regulated HLA-I is a shared feature of TICs in a variety of human sarcomas, and differentiation therapy strategies may specifically target undifferentiated TICs and inhibit tumor formation.

  2. Human adipose tissue-derived mesenchymal stem cells differentiate into insulin, somatostatin, and glucagon expressing cells

    International Nuclear Information System (INIS)

    Timper, Katharina; Seboek, Dalma; Eberhardt, Michael; Linscheid, Philippe; Christ-Crain, Mirjam; Keller, Ulrich; Mueller, Beat; Zulewski, Henryk

    2006-01-01

    Mesenchymal stem cells (MSC) from mouse bone marrow were shown to adopt a pancreatic endocrine phenotype in vitro and to reverse diabetes in an animal model. MSC from human bone marrow and adipose tissue represent very similar cell populations with comparable phenotypes. Adipose tissue is abundant and easily accessible and could thus also harbor cells with the potential to differentiate in insulin producing cells. We isolated human adipose tissue-derived MSC from four healthy donors. During the proliferation period, the cells expressed the stem cell markers nestin, ABCG2, SCF, Thy-1 as well as the pancreatic endocrine transcription factor Isl-1. The cells were induced to differentiate into a pancreatic endocrine phenotype by defined culture conditions within 3 days. Using quantitative PCR a down-regulation of ABCG2 and up-regulation of pancreatic developmental transcription factors Isl-1, Ipf-1, and Ngn3 were observed together with induction of the islet hormones insulin, glucagon, and somatostatin

  3. Chondroitin sulfate effects on neural stem cell differentiation.

    Science.gov (United States)

    Canning, David R; Brelsford, Natalie R; Lovett, Neil W

    2016-01-01

    We have investigated the role chondroitin sulfate has on cell interactions during neural plate formation in the early chick embryo. Using tissue culture isolates from the prospective neural plate, we have measured neural gene expression profiles associated with neural stem cell differentiation. Removal of chondroitin sulfate from stage 4 neural plate tissue leads to altered associations of N-cadherin-positive neural progenitors and causes changes in the normal sequence of neural marker gene expression. Absence of chondroitin sulfate in the neural plate leads to reduced Sox2 expression and is accompanied by an increase in the expression of anterior markers of neural regionalization. Results obtained in this study suggest that the presence of chondroitin sulfate in the anterior chick embryo is instrumental in maintaining cells in the neural precursor state.

  4. Response of Turkey Muscle Satellite Cells to Thermal Challenge. II. Transcriptome Effects in Differentiating Cells

    Directory of Open Access Journals (Sweden)

    Kent M. Reed

    2017-11-01

    Full Text Available Background: Exposure of poultry to extreme temperatures during the critical period of post-hatch growth can seriously affect muscle development and thus compromise subsequent meat quality. This study was designed to characterize transcriptional changes induced in turkey muscle satellite cells by thermal challenge during differentiation. Our goal is to better define how thermal stress alters breast muscle ultrastructure and subsequent development.Results: Skeletal muscle satellite cells previously isolated from the Pectoralis major muscle of 7-wk-old male turkeys (Meleagris gallopavo from two breeding lines: the F-line (16 wk body weight-selected and RBC2 (randombred control line were used in this study. Cultured cells were induced to differentiate at 38°C (control or thermal challenge temperatures of 33 or 43°C. After 48 h of differentiation, cells were harvested and total RNA was isolated for RNAseq analysis. Analysis of 39.9 Gb of sequence found 89% mapped to the turkey genome (UMD5.0, annotation 101 with average expression of 18,917 genes per library. In the cultured satellite cells, slow/cardiac muscle isoforms are generally present in greater abundance than fast skeletal isoforms. Statistically significant differences in gene expression were observed among treatments and between turkey lines, with a greater number of genes affected in the F-line cells following cold treatment whereas more differentially expressed (DE genes were observed in the RBC2 cells following heat treatment. Many of the most significant pathways involved signaling, consistent with ongoing cellular differentiation. Regulation of Ca2+ homeostasis appears to be significantly affected by temperature treatment, particularly cold treatment.Conclusions: Satellite cell differentiation is directly influenced by temperature at the level of gene transcription with greater effects attributed to selection for fast growth. At lower temperature, muscle-associated genes in the

  5. Radotinib Induces Apoptosis of CD11b+ Cells Differentiated from Acute Myeloid Leukemia Cells.

    Directory of Open Access Journals (Sweden)

    Sook-Kyoung Heo

    Full Text Available Radotinib, developed as a BCR/ABL tyrosine kinase inhibitor (TKI, is approved for the second-line treatment of chronic myeloid leukemia (CML in South Korea. However, therapeutic effects of radotinib in acute myeloid leukemia (AML are unknown. In the present study, we demonstrate that radotinib significantly decreases the viability of AML cells in a dose-dependent manner. Kasumi-1 cells were more sensitive to radotinib than NB4, HL60, or THP-1 cell lines. Furthermore, radotinib induced CD11b expression in NB4, THP-1, and Kasumi-1 cells either in presence or absence of all trans-retinoic acid (ATRA. We found that radotinib promoted differentiation and induced CD11b expression in AML cells by downregulating LYN. However, CD11b expression induced by ATRA in HL60 cells was decreased by radotinib through upregulation of LYN. Furthermore, radotinib mainly induced apoptosis of CD11b+ cells in the total population of AML cells. Radotinib also increased apoptosis of CD11b+ HL60 cells when they were differentiated by ATRA/dasatinib treatment. We show that radotinib induced apoptosis via caspase-3 activation and the loss of mitochondrial membrane potential (ΔΨm in CD11b+ cells differentiated from AML cells. Our results suggest that radotinib may be used as a candidate drug in AML or a chemosensitizer for treatment of AML by other therapeutics.

  6. Muscle Spindles and Locomotor Control-An Unrecognized Falls Determinant?

    OpenAIRE

    Marks Ray

    2015-01-01

    BACKGROUND: Historically, evidence muscle spindles might be involved in locomotion was provided by their presence in tetrapod antigravity muscles associated with posture and locomotion. Later, Brodal (1962) noted muscle spindles in all muscles of locomotion. To unravel the complexity of the muscle spindle and its role in human locomotor control many investigators have since conducted lesion and/or anaesthesia studies in subhuman species and human contexts. QUESTIONS: How ...

  7. Electrospun fibrous scaffolds combined with nanoscale hydroxyapatite induce osteogenic differentiation of human periodontal ligament cells

    Directory of Open Access Journals (Sweden)

    Wu XN

    2014-08-01

    Full Text Available Xiaonan Wu,1 Leiying Miao,2,# Yingfang Yao,3 Wenlei Wu,1 Yu Liu,1 Xiaofeng Chen,1 Weibin Sun1,# 1Department of Periodontology, Hospital of Stomatology, Medical School of Nanjing University, Nanjing, People’s Republic of China; 2Department of Cariology and Endodontics, Hospital of Stomatology, Medical School of Nanjing University, Nanjing, People’s Republic of China; 3Eco-materials and Renewable Energy Research Center, Department of Materials Science and Engineering, National Laboratory of Solid State Microstructures, Nanjing University, Nanjing, People’s Republic of China #These authors contributed equally to this work Abstract: Periodontal repair is a complex process in which regeneration of alveolar bone is a vital component. The aim of this study was to develop a biodegradable scaffold with good biocompatibility and osteoinductive ability. Two types of composite fibrous scaffolds were produced by electrospinning, ie, type I collagen/poly(є-caprolactone (COL/PCL and type I collagen/poly(є-caprolactone/nanoscale hydroxyapatite (COL/PCL/nHA with an average fiber diameter of about 377 nm. After a simulated body fluid (SBF immersion test, the COL/PCL/nHA-SBF scaffold developed a rough surface because of the calcium phosphate deposited on the fibers, suggesting that the presence of nHA promoted the mineralization potential of the scaffold. Energy dispersive X-ray spectroscopy clearly showed the calcium and phosphorus content in the COL/PCL/nHA and COL/PCL/nHA-SBF scaffolds, confirming the findings of nHA and calcium phosphate precipitation on scanning electron micrographs. Water contact analysis revealed that nHA could improve the hydrophilic nature of the COL/PCL/nHA-SBF scaffold. The morphology of periodontal ligament cells cultured on COL/PCL-SBF and COL/PCL/nHA-SBF was evaluated by scanning electron microscopy. The results showed that cells adhered to either type of scaffold and were slightly spindle-shaped in the beginning, then

  8. Pigment Cell Differentiation in Sea Urchin Blastula-Derived Primary Cell Cultures

    Science.gov (United States)

    Ageenko, Natalya V.; Kiselev, Konstantin V.; Dmitrenok, Pavel S.; Odintsova, Nelly A.

    2014-01-01

    The quinone pigments of sea urchins, specifically echinochrome and spinochromes, are known for their effective antioxidant, antibacterial, antifungal, and antitumor activities. We developed in vitro technology for inducing pigment differentiation in cell culture. The intensification of the pigment differentiation was accompanied by a simultaneous decrease in cell proliferation. The number of pigment cells was two-fold higher in the cells cultivated in the coelomic fluids of injured sea urchins than in those intact. The possible roles of the specific components of the coelomic fluids in the pigment differentiation process and the quantitative measurement of the production of naphthoquinone pigments during cultivation were examined by MALDI and electrospray ionization mass spectrometry. Echinochrome A and spinochrome E were produced by the cultivated cells of the sand dollar Scaphechinus mirabilis in all tested media, while only spinochromes were found in the cultivated cells of another sea urchin, Strongylocentrotus intermedius. The expression of genes associated with the induction of pigment differentiation was increased in cells cultivated in the presence of shikimic acid, a precursor of naphthoquinone pigments. Our results should contribute to the development of new techniques in marine biotechnology, including the generation of cell cultures producing complex bioactive compounds with therapeutic potential. PMID:24979272

  9. Differentiation-Dependent Glycosylation of Cells in Squamous Cell Epithelia Detected by a Mammalian Lectin

    Czech Academy of Sciences Publication Activity Database

    Plzák, J.; Holíková, Z.; Smetana Jr., K.; Dvořánková, B.; Hercogová, J.; Kaltner, H.; Motlík, Jan; Gabius, H. J.

    2002-01-01

    Roč. 171, - (2002), s. 135-144 ISSN 1422-6405 R&D Projects: GA MŠk LN00A065; GA AV ČR KSK5052113 Keywords : carcinoma * basal cell * cell differentiation Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 1.442, year: 2002

  10. Enteric neural crest cells regulate vertebrate stomach patterning and differentiation.

    Science.gov (United States)

    Faure, Sandrine; McKey, Jennifer; Sagnol, Sébastien; de Santa Barbara, Pascal

    2015-01-15

    In vertebrates, the digestive tract develops from a uniform structure where reciprocal epithelial-mesenchymal interactions pattern this complex organ into regions with specific morphologies and functions. Concomitant with these early patterning events, the primitive GI tract is colonized by the vagal enteric neural crest cells (vENCCs), a population of cells that will give rise to the enteric nervous system (ENS), the intrinsic innervation of the GI tract. The influence of vENCCs on early patterning and differentiation of the GI tract has never been evaluated. In this study, we report that a crucial number of vENCCs is required for proper chick stomach development, patterning and differentiation. We show that reducing the number of vENCCs by performing vENCC ablations induces sustained activation of the BMP and Notch pathways in the stomach mesenchyme and impairs smooth muscle development. A reduction in vENCCs also leads to the transdifferentiation of the stomach into a stomach-intestinal mixed phenotype. In addition, sustained Notch signaling activity in the stomach mesenchyme phenocopies the defects observed in vENCC-ablated stomachs, indicating that inhibition of the Notch signaling pathway is essential for stomach patterning and differentiation. Finally, we report that a crucial number of vENCCs is also required for maintenance of stomach identity and differentiation through inhibition of the Notch signaling pathway. Altogether, our data reveal that, through the regulation of mesenchyme identity, vENCCs act as a new mediator in the mesenchymal-epithelial interactions that control stomach development. © 2015. Published by The Company of Biologists Ltd.

  11. Cell membrane and cell junctions in differentiation of preimplanted mouse embryos.

    Science.gov (United States)

    Izquierdo, L; Fernández, S; López, T

    1976-12-01

    Cell membrane and cell junctions in differentiation of preimplanted mouse embryos, (membrana celular y uniones celulares en la diferenciación del embrión de ratón antes de la implantación). Arch. Biol. Med. Exper. 10: 130-134, 1976. The development of cell junctions that seal the peripheral blastomeres could be a decisive step in the differentiation of morulae into blastocysts. The appearance of these junctions is studied by electron microscopy of late morulae and initial blastocysts. Zonulae occludentes as well as impermeability to lanthanum emulsion precedes the appearance of the blastocel and hence might be considered as one of its necessary causes.

  12. Stem cell proliferation and differentiation a multitype branching process model

    CERN Document Server

    Macken, Catherine A

    1988-01-01

    The body contains many cellular systems that require the continuous production of new, fully functional, differentiated cells to replace cells lacking or having limited self-renewal capabilities that die or are damaged during the lifetime of an individual. Such systems include the epidermis, the epithelial lining of the gut, and the blood. For example, erythrocytes (red blood cells) lack nuclei and thus are incapable of self-replication. They have a life span in the circulation of about 120 days. Mature granulocytes, which also lack proliferative capacity, have a much shorter life span - typically 12 hours, though this may be reduced to only two or three hours in times of serious tissue infection. Perhaps a more familiar example is the outermost layer of the skin. This layer is composed of fully mature, dead epidermal cells that must be replaced by the descendants of stem cells lodged in lower layers of the epidermis (cf. Alberts et al. , 1983). In total, to supply the normal steady-state demands of cells, an...

  13. Combination spindle-drive system for high precision machining

    Science.gov (United States)

    Gerth, Howard L.

    1977-07-26

    A combination spindle-drive is provided for fabrication of optical quality surface finishes. Both the spindle-and-drive utilize the spindle bearings for support, thereby removing the conventional drive-means bearings as a source of vibration. An airbearing spindle is modified to carry at the drive end a highly conductive cup-shaped rotor which is aligned with a stationary stator to produce torque in the cup-shaped rotor through the reaction of eddy currents induced in the rotor. This arrangement eliminates magnetic attraction forces and all force is in the form of torque on the cup-shaped rotor.

  14. Modal analysis of spindle of grinder machine based on ANSYS

    Directory of Open Access Journals (Sweden)

    HE Chaocong

    2015-10-01

    Full Text Available The object of research is to a certain type grinding wheel spindle for which a 3D model of the spindle is established by SolidWorks software and ANSYS software is imported for model analysis.Natural frequency,vibration type and critical speed of the spindle model are obtained and the resulting data are scientifically analyzed.The results show that the spindle structure is reasonable,the machining accuracy can be ensured and the position where the most severe deformation and the main shaft fatigue fracture may occur can be found out,which also provide the theoretical basis for further optimization design and precision control.

  15. Modal analysis of spindle of grinder machine based on ANSYS

    OpenAIRE

    HE Chaocong; LIU Peipei; YAN Chunfei; WANG Muhuan; LIN Jun

    2015-01-01

    The object of research is to a certain type grinding wheel spindle for which a 3D model of the spindle is established by SolidWorks software and ANSYS software is imported for model analysis.Natural frequency,vibration type and critical speed of the spindle model are obtained and the resulting data are scientifically analyzed.The results show that the spindle structure is reasonable,the machining accuracy can be ensured and the position where the most severe deformation and the main shaft fat...

  16. Posttranscriptional (Re)programming of Cell Fate: Examples in Stem Cells, Progenitor, and Differentiated Cells.

    Science.gov (United States)

    Kanellopoulou, Chrysi; Muljo, Stefan A

    2018-01-01

    How a single genome can give rise to many different transcriptomes and thus all the different cell lineages in the human body is a fundamental question in biology. While signaling pathways, transcription factors, and chromatin architecture, to name a few determinants, have been established to play critical roles, recently, there is a growing appreciation of the roles of non-coding RNAs and RNA-binding proteins in controlling cell fates posttranscriptionally. Thus, it is vital that these emerging players are also integrated into models of gene regulatory networks that underlie programs of cellular differentiation. Sometimes, we can leverage knowledge about such posttranscriptional circuits to reprogram patterns of gene expression in meaningful ways. Here, we review three examples from our work.

  17. Free Vibration Analysis of a Spinning Flexible DISK-SPINDLE System Supported by Ball Bearing and Flexible Shaft Using the Finite Element Method and Substructure Synthesis

    Science.gov (United States)

    JANG, G. H.; LEE, S. H.; JUNG, M. S.

    2002-03-01

    Free vibration of a spinning flexible disk-spindle system supported by ball bearing and flexible shaft is analyzed by using Hamilton's principle, FEM and substructure synthesis. The spinning disk is described by using the Kirchhoff plate theory and von Karman non-linear strain. The rotating spindle and stationary shaft are modelled by Rayleigh beam and Euler beam respectively. Using Hamilton's principle and including the rigid body translation and tilting motion, partial differential equations of motion of the spinning flexible disk and spindle are derived consistently to satisfy the geometric compatibility in the internal boundary between substructures. FEM is used to discretize the derived governing equations, and substructure synthesis is introduced to assemble each component of the disk-spindle-bearing-shaft system. The developed method is applied to the spindle system of a computer hard disk drive with three disks, and modal testing is performed to verify the simulation results. The simulation result agrees very well with the experimental one. This research investigates critical design parameters in an HDD spindle system, i.e., the non-linearity of a spinning disk and the flexibility and boundary condition of a stationary shaft, to predict the free vibration characteristics accurately. The proposed method may be effectively applied to predict the vibration characteristics of a spinning flexible disk-spindle system supported by ball bearing and flexible shaft in the various forms of computer storage device, i.e., FDD, CD, HDD and DVD.

  18. Single-cell entropy for accurate estimation of differentiation potency from a cell's transcriptome

    Science.gov (United States)

    Teschendorff, Andrew E.; Enver, Tariq

    2017-01-01

    The ability to quantify differentiation potential of single cells is a task of critical importance. Here we demonstrate, using over 7,000 single-cell RNA-Seq profiles, that differentiation potency of a single cell can be approximated by computing the signalling promiscuity, or entropy, of a cell's transcriptome in the context of an interaction network, without the need for feature selection. We show that signalling entropy provides a more accurate and robust potency estimate than other entropy-based measures, driven in part by a subtle positive correlation between the transcriptome and connectome. Signalling entropy identifies known cell subpopulations of varying potency and drug resistant cancer stem-cell phenotypes, including those derived from circulating tumour cells. It further reveals that expression heterogeneity within single-cell populations is regulated. In summary, signalling entropy allows in silico estimation of the differentiation potency and plasticity of single cells and bulk samples, providing a means to identify normal and cancer stem-cell phenotypes. PMID:28569836

  19. Odontoblast-Like Cells Differentiated from Dental Pulp Stem Cells Retain Their Phenotype after Subcultivation

    Directory of Open Access Journals (Sweden)

    Paula A. Baldión

    2018-01-01

    Full Text Available Odontoblasts, the main cell type in teeth pulp tissue, are not cultivable and they are responsible for the first line of response after dental restauration. Studies on dental materials cytotoxicity and odontoblast cells physiology require large quantity of homogenous cells retaining most of the phenotype characteristics. Odontoblast-like cells (OLC were differentiated from human dental pulp stem cells using differentiation medium (containing TGF-β1, and OLC expanded after trypsinization (EXP-21 were evaluated and compared. Despite a slower cell growth curve, EXP-21 cells express similarly the odontoblast markers dentinal sialophosphoprotein and dentin matrix protein-1 concomitantly with RUNX2 transcripts and low alkaline phosphatase activity as expected. Both OLC and EXP-21 cells showed similar mineral deposition activity evidenced by alizarin red and von Kossa staining. These results pointed out minor changes in phenotype of subcultured EXP-21 regarding the primarily differentiated OLC, making the subcultivation of these cells a useful strategy to obtain odontoblasts for biocompatibility or cell physiology studies in dentistry.

  20. Differentiation of Mouse Ovarian Stem Cells Toward Oocyte-Like Structure by Coculture with Granulosa Cells.

    Science.gov (United States)

    Parvari, Soraya; Yazdekhasti, Hossein; Rajabi, Zahra; Gerayeli Malek, Valliollah; Rastegar, Tayebeh; Abbasi, Mehdi

    2016-11-01

    An increasing body of evidence has confirmed existence and function of ovarian stem cells (OSCs). In this study, a novel approach on differentiation of OSCs into oocyte-like cells (OLCs) has been addressed. Recently, different methods have been recruited to isolate and describe aspects of OSCs, but newer and more convenient strategies in isolation are still growing. Herein, a morphology-based method was used to isolate OSCs. Cell suspension of mouse neonatal ovaries was cultured and formed colonies were harvested mechanically and cultivated on mouse embryonic fibroblasts. For differentiation induction, colonies transferred on inactive granulosa cells. Results showed that cells in colonies were positive for alkaline phosphatase activity and reverse transcription-polymerase chain reaction (RT-PCR) confirmed the pluripotency characteristics of cells. Immunofluorescence revealed a positive signal for OCT4, DAZL, MVH, and SSEA1 in colonies as well. Results of RT-PCR and immunofluorescence confirmed that some OLCs were generated within the germ stem cell (GSCs) colonies. The applicability of morphological selection for isolation of GSCs was verified. This method is easier and more economic than other techniques. Our results demonstrate that granulosa cells were effective in inducing the differentiation of OSCs into OLCs through direct cell-to-cell contacts.

  1. Adipose Stem Cell Therapy Mitigates Chronic Pancreatitis via Differentiation into Acinar-like Cells in Mice.

    Science.gov (United States)

    Sun, Zhen; Gou, Wenyu; Kim, Do-Sung; Dong, Xiao; Strange, Charlie; Tan, Yu; Adams, David B; Wang, Hongjun

    2017-11-01

    The objective of this study was to assess the capacity of adipose-derived mesenchymal stem cells (ASCs) to mitigate disease progression in an experimental chronic pancreatitis mouse model. Chronic pancreatitis (CP) was induced in C57BL/6 mice by repeated ethanol and cerulein injection, and mice were then infused with 4 × 10 5 or 1 × 10 6 GFP + ASCs. Pancreas morphology, fibrosis, inflammation, and presence of GFP + ASCs in pancreases were assessed 2 weeks after treatment. We found that ASC infusion attenuated pancreatic damage, preserved pancreas morphology, and reduced pancreatic fibrosis and cell death. GFP + ASCs migrated to pancreas and differentiated into amylase + cells. In further confirmation of the plasticity of ASCs, ASCs co-cultured with acinar cells in a Transwell system differentiated into amylase + cells with increased expression of acinar cell-specific genes including amylase and chymoB1. Furthermore, culture of acinar or pancreatic stellate cell lines in ASC-conditioned medium attenuated ethanol and cerulein-induced pro-inflammatory cytokine production in vitro. Our data show that a single intravenous injection of ASCs ameliorated CP progression, likely by directly differentiating into acinar-like cells and by suppressing inflammation, fibrosis, and pancreatic tissue damage. These results suggest that ASC cell therapy has the potential to be a valuable treatment for patients with pancreatitis. Copyright © 2017 The American Society of Gene and Cell Therapy. Published by Elsevier Inc. All rights reserved.

  2. Single-Cell RNA-Sequencing Reveals a Continuous Spectrum of Differentiation in Hematopoietic Cells

    Directory of Open Access Journals (Sweden)

    Iain C. Macaulay

    2016-02-01

    Full Text Available The transcriptional programs that govern hematopoiesis have been investigated primarily by population-level analysis of hematopoietic stem and progenitor cells, which cannot reveal the continuous nature of the differentiation process. Here we applied single-cell RNA-sequencing to a population of hematopoietic cells in zebrafish as they undergo thrombocyte lineage commitment. By reconstructing their developmental chronology computationally, we were able to place each cell along a continuum from stem cell to mature cell, refining the traditional lineage tree. The progression of cells along this continuum is characterized by a highly coordinated transcriptional program, displaying simultaneous suppression of genes involved in cell proliferation and ribosomal biogenesis as the expression of lineage specific genes increases. Within this program, there is substantial heterogeneity in the expression of the key lineage regulators. Overall, the total number of genes expressed, as well as the total mRNA content of the cell, decreases as the cells undergo lineage commitment.

  3. Reconstitution of mammary epithelial morphogenesis by murine embryonic stem cells undergoing hematopoietic stem cell differentiation.

    Directory of Open Access Journals (Sweden)

    Shuxian Jiang

    2010-03-01

    Full Text Available Mammary stem cells are maintained within specific microenvironments and recruited throughout lifetime to reconstitute de novo the mammary gland. Mammary stem cells have been isolated through the identification of specific cell surface markers and in vivo transplantation into cleared mammary fat pads. Accumulating evidence showed that during the reformation of mammary stem cell niches by dispersed epithelial cells in the context of the intact epithelium-free mammary stroma, non-mammary epithelial cells may be sequestered and reprogrammed to perform mammary epithelial cell functions and to adopt mammary epithelial characteristics during reconstruction of mammary epithelium in regenerating mammary tissue in vivo.To examine whether other types of progenitor cells are able to contribute to mammary branching morphogenesis, we examined the potential of murine embryonic stem (mES cells, undergoing hematopoietic differentiation, to support mammary reconstitution in vivo. We observed that cells from day 14 embryoid bodies (EBs under hematopoietic differentiation condition, but not supernatants derived from these cells, when transplanted into denuded mammary fat pads, were able to contribute to both the luminal and myoepithelial lineages in branching ductal structures resembling the ductal-alveolar architecture of the mammary tree. No teratomas were observed when these cells were transplanted in vivo.Our data provide evidence for the dominance of the tissue-specific mammary stem cell niche and its role in directing mES cells, undergoing hematopoietic differentiation, to reprogram into mammary epithelial cells and to promote mammary epithelial morphogenesis. These studies should also provide insights into regeneration of damaged mammary gland and the role of the mammary microenvironment in reprogramming cell fate.

  4. A single-cell resolution map of mouse hematopoietic stem and progenitor cell differentiation.

    Science.gov (United States)

    Nestorowa, Sonia; Hamey, Fiona K; Pijuan Sala, Blanca; Diamanti, Evangelia; Shepherd, Mairi; Laurenti, Elisa; Wilson, Nicola K; Kent, David G; Göttgens, Berthold

    2016-08-25

    Maintenance of the blood system requires balanced cell fate decisions by hematopoietic stem and progenitor cells (HSPCs). Because cell fate choices are executed at the individual cell level, new single-cell profiling technologies offer exciting possibilities for mapping the dynamic molecular changes underlying HSPC differentiation. Here, we have used single-cell RNA sequencing to profile more than 1600 single HSPCs, and deep sequencing has enabled detection of an average of 6558 protein-coding genes per cell. Index sorting, in combination with broad sorting gates, allowed us to retrospectively assign cells to 12 commonly sorted HSPC phenotypes while also capturing intermediate cells typically excluded by conventional gating. We further show that independently generated single-cell data sets can be projected onto the single-cell resolution expression map to directly compare data from multiple groups and to build and refine new hypotheses. Reconstruction of differentiation trajectories reveals dynamic expression changes associated with early lymphoid, erythroid, and granulocyte-macrophage differentiation. The latter two trajectories were characterized by common upregulation of cell cycle and oxidative phosphorylation transcriptional programs. By using external spike-in controls, we estimate absolute messenger RNA (mRNA) levels per cell, showing for the first time that despite a general reduction in total mRNA, a subset of genes shows higher expression levels in immature stem cells consistent with active maintenance of the stem-cell state. Finally, we report the development of an intuitive Web interface as a new community resource to permit visualization of gene expression in HSPCs at single-cell resolution for any gene of choice. © 2016 by The American Society of Hematology.

  5. Cell kinetics, DNA integrity, differentiation, and lipid fingerprinting analysis of rabbit adipose-derived stem cells.

    Science.gov (United States)

    Barretto, Letícia Siqueira de Sá; Lessio, Camila; Sawaki e Nakamura, Ahy Natally; Lo Turco, Edson Guimarães; da Silva, Camila Gonzaga; Zambon, João Paulo; Gozzo, Fábio César; Pilau, Eduardo Jorge; de Almeida, Fernando Gonçalves

    2014-10-01

    Human adipose tissue has been described as a potential alternative reservoir for stem cells. Although studies have been performed in rabbits using autologous adipose-derived stem cells (ADSC), these cells have not been well characterized. The primary objectives of this study were to demonstrate the presence of adipose-derived stem cells isolated from rabbit inguinal fat pads and to characterize them through osteogenic and adipogenic in vitro differentiation and lipid fingerprinting analysis. The secondary objective was to evaluate cell behavior through growth kinetics, cell viability, and DNA integrity. Rabbit ADSCs were isolated to determine the in vitro growth kinetics and cell viability. DNA integrity was assessed by an alkaline Comet assay in passages 0 and 5. The osteogenic differentiation was evaluated by Von Kossa, and Alizarin Red S staining and adipogenic differentiation were assessed by Oil Red O staining. Lipid fingerprinting analyses of control, adipogenic, and osteogenic differentiated cells were performed by MALDI-TOF/MS. We demonstrate that rabbit ADSC have a constant growth rate at the early passages, with increased DNA fragmentation at or after passage 5. Rabbit ADSC viability was similar in passages 2 and 5 (90.7% and 86.6%, respectively), but there was a tendency to decreased cellular growth rate after passage 3. The ADSC were characterized by the expression of surface markers such as CD29 (67.4%) and CD44 (89.4%), using CD 45 (0.77%) as a negative control. ADSC from rabbits were successfully isolated form the inguinal region. These cells were capable to differentiate into osteogenic and adipogenic tissue when they were placed in inductive media. After each passage, there was a trend towards decreased cell growth. On the other hand, DNA fragmentation increased at each passage. ADSC had a different lipid profile when placed in control, adipogenic, or osteogenic media.

  6. Calpain expression and activity during lens fiber cell differentiation.

    Science.gov (United States)

    De Maria, Alicia; Shi, Yanrong; Kumar, Nalin M; Bassnett, Steven

    2009-05-15

    In animal models, the dysregulated activity of calcium-activated proteases, calpains, contributes directly to cataract formation. However, the physiological role of calpains in the healthy lens is not well defined. In this study, we examined the expression pattern of calpains in the mouse lens. Real time PCR and Western blotting data indicated that calpain 1, 2, 3, and 7 were expressed in lens fiber cells. Using controlled lysis, depth-dependent expression profiles for each calpain were obtained. These indicated that, unlike calpain 1, 2, and 7, which were most abundant in cells near the lens surface, calpain 3 expression was strongest in the deep cortical region of the lens. We detected calpain activities in vitro and showed that calpains were active in vivo by microinjecting fluorogenic calpain substrates into cortical fiber cells. To identify endogenous calpain substrates, membrane/cytoskeleton preparations were treated with recombinant calpain, and cleaved products were identified by two-dimensional difference electrophoresis/mass spectrometry. Among the calpain substrates identified by this approach was alphaII-spectrin. An antibody that specifically recognized calpain-cleaved spectrin was used to demonstrate that spectrin is cleaved in vivo, late in fiber cell differentiation, at or about the time that lens organelles are degraded. The generation of the calpain-specific spectrin cleavage product was not observed in lens tissue from calpain 3-null mice, indicating that calpain 3 is uniquely activated during lens fiber differentiation. Our data suggest a role for calpains in the remodeling of the membrane cytoskeleton that occurs with fiber cell maturation.

  7. v-Src causes delocalization of Mklp1, Aurora B, and INCENP from the spindle midzone during cytokinesis failure

    Energy Technology Data Exchange (ETDEWEB)

    Soeda, Shuhei [Department of Molecular Cell Biology, Graduate School of Pharmaceutical Sciences, Chiba University, Inohana 1-8-1, Chuo-ku, Chiba 260-8675 (Japan); Nakayama, Yuji, E-mail: nakayama@mb.kyoto-phu.ac.jp [Department of Molecular Cell Biology, Graduate School of Pharmaceutical Sciences, Chiba University, Inohana 1-8-1, Chuo-ku, Chiba 260-8675 (Japan); Department of Biochemistry and Molecular Biology, Kyoto Pharmaceutical University, 5 Nakauchi-cho, Misasagi, Yamashina-ku, Kyoto 607-8414 (Japan); Honda, Takuya; Aoki, Azumi; Tamura, Naoki; Abe, Kohei; Fukumoto, Yasunori [Department of Molecular Cell Biology, Graduate School of Pharmaceutical Sciences, Chiba University, Inohana 1-8-1, Chuo-ku, Chiba 260-8675 (Japan); Yamaguchi, Naoto, E-mail: nyama@faculty.chiba-u.jp [Department of Molecular Cell Biology, Graduate School of Pharmaceutical Sciences, Chiba University, Inohana 1-8-1, Chuo-ku, Chiba 260-8675 (Japan)

    2013-06-10

    Src-family tyrosine kinases are aberrantly activated in cancers, and this activation is associated with malignant tumor progression. v-Src, encoded by the v-src transforming gene of the Rous sarcoma virus, is a mutant variant of the cellular proto-oncogene c-Src. Although investigations with temperature sensitive mutants of v-Src have shown that v-Src induces many oncogenic processes, the effects on cell division are unknown. Here, we show that v-Src inhibits cellular proliferation of HCT116, HeLa S3 and NIH3T3 cells. Flow cytometry analysis indicated that inducible expression of v-Src results in an accumulation of 4N cells. Time-lapse analysis revealed that binucleation is induced through the inhibition of cytokinesis, a final step of cell division. The localization of Mklp1, which is essential for cytokinesis, to the spindle midzone is inhibited in v-Src-expressing cells. Intriguingly, Aurora B, which regulates Mklp1 localization at the midzone, is delocalized from the spindle midzone and the midbody but not from the metaphase chromosomes upon v-Src expression. Mklp2, which is responsible for the relocation of Aurora B from the metaphase chromosomes to the spindle midzone, is also lost from the spindle midzone. These results suggest that v-Src inhibits cytokinesis through the delocalization of Mklp1 and Aurora B from the spindle midzone, resulting in binucleation. -- Highlights: • v-Src inhibits cell proliferation of HCT116, HeLa S3 and NIH3T3 cells. • v-Src induces binucleation together with cytokinesis failure. • v-Src causes delocalization of Mklp1, Aurora B and INCENP from the spindle midzone.

  8. Rapid, Directed Differentiation of Retinal Pigment Epithelial Cells from Human Embryonic or Induced Pluripotent Stem Cells

    OpenAIRE

    Foltz, LP; Clegg, DO

    2017-01-01

    We describe a robust method to direct the differentiation of pluripotent stem cells into retinal pigment epithelial cells (RPE). The purpose of providing a detailed and thorough protocol is to clearly demonstrate each step and to make this readily available to researchers in the field. This protocol results in a homogenous layer of RPE with minimal or no manual dissection needed. The method presented here has been shown to be effective for induced pluripotent stem cells (iPSC) and human embry...

  9. EFHC1, a protein mutated in juvenile myoclonic epilepsy, associates with the mitotic spindle through its N-terminus

    International Nuclear Information System (INIS)

    Nijs, Laurence de; Lakaye, Bernard; Coumans, Bernard; Leon, Christine; Ikeda, Takashi; Delgado-Escueta, Antonio V.; Grisar, Thierry; Chanas, Grazyna

    2006-01-01

    A novel gene, EFHC1, mutated in juvenile myoclonic epilepsy (JME) encodes a protein with three DM10 domains of unknown function and one putative EF-hand motif. To study the properties of EFHC1, we expressed EGFP-tagged protein in various cell lines. In interphase cells, the fusion protein was present in the cytoplasm and in the nucleus with specific accumulation at the centrosome. During mitosis EGFP-EFHC1 colocalized with the mitotic spindle, especially at spindle poles and with the midbody during cytokinesis. Using a specific antibody, we demonstrated the same distribution of the endogenous protein. Deletion analyses revealed that the N-terminal region of EFHC1 is crucial for the association with the mitotic spindle and the midbody. Our results suggest that EFHC1 could play an important role during cell division

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

    Science.gov (United States)

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

    2018-06-01

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

  11. Collagen Type I Improves the Differentiation of Human Embryonic Stem Cells towards Definitive Endoderm

    DEFF Research Database (Denmark)

    Rasmussen, Camilla Holzmann; Petersen, Dorthe Roenn; Møller, Jonas Bech

    2015-01-01

    Human embryonic stem cells have the ability to generate all cell types in the body and can potentially provide an unlimited source of cells for cell replacement therapy to treat degenerative diseases such as diabetes. Current differentiation protocols of human embryonic stem cells towards insulin...... and consistent differentiation of stem cells to definitive endoderm. The results shed light on the importance of extracellular matrix proteins for differentiation and also points to a cost effective and easy method to improve differentiation....... embryonic stem cells to the definitive endoderm lineage. The percentage of definitive endoderm cells after differentiation on collagen I and fibronectin was >85% and 65%, respectively. The cells on collagen I substrates displayed different morphology and gene expression during differentiation as assessed...

  12. Planar Cell Polarity Controls Pancreatic Beta Cell Differentiation and Glucose Homeostasis

    Directory of Open Access Journals (Sweden)

    Cedric Cortijo

    2012-12-01

    Full Text Available Planar cell polarity (PCP refers to the collective orientation of cells within the epithelial plane. We show that progenitor cells forming the ducts of the embryonic pancreas express PCP proteins and exhibit an active PCP pathway. Planar polarity proteins are acquired at embryonic day 11.5 synchronously to apicobasal polarization of pancreas progenitors. Loss of function of the two PCP core components Celsr2 and Celsr3 shows that they control the differentiation of endocrine cells from polarized progenitors, with a prevalent effect on insulin-producing beta cells. This results in a decreased glucose clearance. Loss of Celsr2 and 3 leads to a reduction of Jun phosphorylation in progenitors, which, in turn, reduces beta cell differentiation from endocrine progenitors. These results highlight the importance of the PCP pathway in cell differentiation in vertebrates. In addition, they reveal that tridimensional organization and collective communication of cells are needed in the pancreatic epithelium in order to generate appropriate numbers of endocrine cells.

  13. Interplay between microtubule bundling and sorting factors ensures acentriolar spindle stability during C. elegans oocyte meiosis.

    Directory of Open Access Journals (Sweden)

    Timothy J Mullen

    2017-09-01

    Full Text Available In many species, oocyte meiosis is carried out in the absence of centrioles. As a result, microtubule organization, spindle assembly, and chromosome segregation proceed by unique mechanisms. Here, we report insights into the principles underlying this specialized form of cell division, through studies of C. elegans KLP-15 and KLP-16, two highly homologous members of the kinesin-14 family of minus-end-directed kinesins. These proteins localize to the acentriolar oocyte spindle and promote microtubule bundling during spindle assembly; following KLP-15/16 depletion, microtubule bundles form but then collapse into a disorganized array. Surprisingly, despite this defect we found that during anaphase, microtubules are able to reorganize into a bundled array that facilitates chromosome segregation. This phenotype therefore enabled us to identify factors promoting microtubule organization during anaphase, whose contributions are normally undetectable in wild-type worms; we found that SPD-1 (PRC1 bundles microtubules and KLP-18 (kinesin-12 likely sorts those bundles into a functional orientation capable of mediating chromosome segregation. Therefore, our studies have revealed an interplay between distinct mechanisms that together promote spindle formation and chromosome segregation in the absence of structural cues such as centrioles.

  14. Abnormal spindles in second meiosis in canola (Brassica napus and Brassica campestris

    Directory of Open Access Journals (Sweden)

    Alice Maria de Souza

    1999-01-01

    Full Text Available Studies were carried out on the occurrence of abnormal spindles in the second meiotic division in some canola cultivars recently introduced in Brazil. Fusion of spindles was observed in metaphase II rejoining the two sets of chromosomes segregated in anaphase I and also sequential and tripolar spindles were discovered rejoining two sets of chromatids segregated in anaphase II. The frequency of cells with abnormal spindles ranged from 3.18 to 8.10%. The results suggested that this abnormality was caused by environmental stress that affected the plants during the blooming period.O presente estudo descreve a ocorrência de fusos anormais na segunda divisão meiótica em algumas cultivares da canola recentemente introduzidas no Brasil. Fusão de fusos foi observada em metáfase II reunindo os dois conjuntos cromossômicos segregados na anáfase I; fusos sequenciais e tripolares reunindo cromátides segregadas na anáfase II também foram observados. A frequência de células com fusos anormais variou de 3,18 a 8,10% entre as variedades. Os resultados sugerem que estas anormalidades foram causadas por condições climáticas adversas que afetaram as plantas no período de florescimento. As implicações genéticas destas anormalidades são descritas.

  15. A SUMOylation Motif in Aurora-A: Implications for Spindle Dynamics and Oncogenesis

    Energy Technology Data Exchange (ETDEWEB)

    Pérez de Castro, Ignacio; Aguirre-Portolés, Cristina [Molecular Oncology Programme, Cell Division and Cancer Group, Centro Nacional de Investigaciones Oncológicas, Madrid (Spain); Martin, Benedicte [CNRS-UMR 6061, Institut de Génétique et Développement de Rennes, IFR 140 GFAS, Faculté de Médecine, Université Rennes 1, Rennes (France); Fernández-Miranda, Gonzalo [Molecular Oncology Programme, Cell Division and Cancer Group, Centro Nacional de Investigaciones Oncológicas, Madrid (Spain); Klotzbucher, Andrea; Kubbutat, Michael H. G. [ProQinase GmBH, Freiburg (Germany); Megías, Diego [Confocal Microscopy Core Unit, Centro Nacional de Investigaciones Oncológicas, Madrid (Spain); Arlot-Bonnemains, Yannick [CNRS-UMR 6061, Institut de Génétique et Développement de Rennes, IFR 140 GFAS, Faculté de Médecine, Université Rennes 1, Rennes (France); Malumbres, Marcos, E-mail: mmm@cnio.es, E-mail: iperez@cnio.es [Molecular Oncology Programme, Cell Division and Cancer Group, Centro Nacional de Investigaciones Oncológicas, Madrid (Spain)

    2011-12-14

    Aurora-A is a serine/threonine kinase that plays critical roles in centrosome maturation, spindle dynamics, and chromosome orientation and it is frequently over-expressed in human cancers. In this work, we show that Aurora-A interacts with the SUMO-conjugating enzyme UBC9 and co-localizes with SUMO1 in mitotic cells. Aurora-A can be SUMOylated in vitro and in vivo. Mutation of the highly conserved SUMOylation residue lysine 249 significantly disrupts Aurora-A SUMOylation and mitotic defects characterized by defective and multipolar spindles ensue. The Aurora-A{sup K249R} mutant has normal kinase activity but displays altered dynamics at the mitotic spindle. In addition, ectopic expression of the Aurora-A{sup K249R} mutant results in a significant increase in susceptibility to malignant transformation induced by the Ras oncogene. These data suggest that modification by SUMO residues may control Aurora-A function at the spindle and that deficiency of SUMOylation of this kinase may have important implications for tumor development.

  16. Absence of Rybp Compromises Neural Differentiation of Embryonic Stem Cells

    Directory of Open Access Journals (Sweden)

    Gergo Kovacs

    2016-01-01

    Full Text Available Rybp (Ring1 and Yy1 Binding Protein is a transcriptional regulator and member of the noncanonical polycomb repressive complex 1 with essential role in early embryonic development. We have previously described that alteration of Rybp dosage in mouse models induced striking neural tube defects (NTDs, exencephaly, and disorganized neurocortex. In this study we further investigated the role of Rybp in neural differentiation by utilising wild type (rybp+/+ and rybp null mutant (rybp-/- embryonic stem cells (ESCs and tried to uncover underlying molecular events that are responsible for the observed phenotypic changes. We found that rybp null mutant ESCs formed less matured neurons, astrocytes, and oligodendrocytes from existing progenitors than wild type cells. Furthermore, lack of rybp coincided with altered gene expression of key neural markers including Pax6 and Plagl1 pinpointing a possible transcriptional circuit among these genes.

  17. Mammalian cochlear supporting cells can divide and trans-differentiate into hair cells.

    Science.gov (United States)

    White, Patricia M; Doetzlhofer, Angelika; Lee, Yun Shain; Groves, Andrew K; Segil, Neil

    2006-06-22

    Sensory hair cells of the mammalian organ of Corti in the inner ear do not regenerate when lost as a consequence of injury, disease, or age-related deafness. This contrasts with other vertebrates such as birds, where the death of hair cells causes surrounding supporting cells to re-enter the cell cycle and give rise to both new hair cells and supporting cells. It is not clear whether the lack of mammalian hair cell regeneration is due to an intrinsic inability of supporting cells to divide and differentiate or to an absence or blockade of regenerative signals. Here we show that post-mitotic supporting cells purified from the postnatal mouse cochlea retain the abi