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Sample records for cells mediates consolidation

  1. Cerebellar vermis H₂ receptors mediate fear memory consolidation in mice.

    Science.gov (United States)

    Gianlorenço, A C L; Riboldi, A M; Silva-Marques, B; Mattioli, R

    2015-02-01

    Histaminergic fibers are present in the molecular and granular layers of the cerebellum and have a high density in the vermis and flocullus. Evidence supports that the cerebellar histaminergic system is involved in memory consolidation. Our recent study showed that histamine injections facilitate the retention of an inhibitory avoidance task, which was abolished by pretreatment with an H2 receptor antagonist. In the present study, we investigated the effects of intracerebellar post training injections of H1 and H2 receptor antagonists as well as the selective H2 receptor agonist on fear memory consolidation. The cerebellar vermi of male mice were implanted with guide cannulae, and after three days of recovery, the inhibitory avoidance test was performed. Immediately after a training session, animals received a microinjection of the following histaminergic drugs: experiment 1, saline or chlorpheniramine (0.016, 0.052 or 0.16 nmol); experiment 2, saline or ranitidine (0.57, 2.85 or 5.07 nmol); and experiment 3, saline or dimaprit (1, 2 or 4 nmol). Twenty-four hours later, a retention test was performed. The data were analyzed using one-way analysis of variance (ANOVA) and Duncan's tests. Animals microinjected with chlorpheniramine did not show any behavioral effects at the doses that we used. Intra-cerebellar injection of the H2 receptor antagonist ranitidine inhibited, while the selective H2 receptor agonist dimaprit facilitated, memory consolidation, suggesting that H2 receptors mediate memory consolidation in the inhibitory avoidance task in mice.

  2. Bortezomib consolidation after autologous stem cell transplantation in multiple myeloma

    DEFF Research Database (Denmark)

    Mellqvist, Ulf-Henrik; Gimsing, Peter; Hjertner, Oyvind;

    2013-01-01

    The Nordic Myeloma Study Group conducted an open randomized trial to compare bortezomib as consolidation therapy given after high-dose therapy and autologous stem cell transplantation (ASCT) with no consolidation in bortezomib-naive patients with newly diagnosed multiple myeloma. Overall, 370...

  3. Astrocytic β2-adrenergic receptors mediate hippocampal long-term memory consolidation

    KAUST Repository

    Gao, Virginia

    2016-07-12

    Emotionally relevant experiences form strong and long-lasting memories by critically engaging the stress hormone/neurotransmitter noradrenaline, which mediates and modulates the consolidation of these memories. Noradrenaline acts through adrenergic receptors (ARs), of which β2- Adrenergic receptors (βARs) are of particular importance. The differential anatomical and cellular distribution of βAR subtypes in the brain suggests that they play distinct roles in memory processing, although much about their specific contributions and mechanisms of action remains to be understood. Here we show that astrocytic rather than neuronal β2ARs in the hippocampus play a key role in the consolidation of a fear-based contextual memory. These hippocampal β2ARs, but not β1ARs, are coupled to the training-dependent release of lactate from astrocytes, which is necessary for long- Term memory formation and for underlying molecular changes. This key metabolic role of astrocytic β2ARs may represent a novel target mechanism for stress-related psychopathologies and neurodegeneration.

  4. Silencing the Majority of Cerebellar Granule Cells Uncovers Their Essential Role in Motor Learning and Consolidation

    Directory of Open Access Journals (Sweden)

    Elisa Galliano

    2013-04-01

    Full Text Available Cerebellar granule cells (GCs account for more than half of all neurons in the CNS of vertebrates. Theoretical work has suggested that the abundance of GCs is advantageous for sparse coding during memory formation. Here, we minimized the output of the majority of GCs by selectively eliminating their CaV2.1 (P/Q-type Ca2+ channels, which mediate the bulk of their neurotransmitter release. This resulted in reduced GC output to Purkinje cells (PCs and stellate cells (SCs as well as in impaired long-term plasticity at GC-PC synapses. As a consequence modulation amplitude and regularity of simple spike (SS output were affected. Surprisingly, the overall motor performance was intact, whereas demanding motor learning and memory consolidation tasks were compromised. Our findings indicate that a minority of functionally intact GCs is sufficient for the maintenance of basic motor performance, whereas acquisition and stabilization of sophisticated memories require higher numbers of normal GCs controlling PC firing.

  5. Assay of mast cell mediators

    DEFF Research Database (Denmark)

    Rådinger, Madeleine; Jensen, Bettina M; Swindle, Emily;

    2015-01-01

    Mediator release from activated mast cells is a major initiator of the symptomology associated with allergic disorders such as anaphylaxis and asthma. Thus, methods to monitor the generation and release of such mediators have widespread applicability in studies designed to understand the processes...... regulating mast cell activation and for the identification of therapeutic approaches to block mast cell-driven disease. In this chapter, we discuss approaches used for the determination of mast cell degranulation, lipid-derived inflammatory mediator production, and cytokine/chemokine gene expression as well...

  6. Consolidated pretreatment and hydrolysis of plant biomass expressing cell wall degrading enzymes

    Energy Technology Data Exchange (ETDEWEB)

    Raab, R. Michael; Zhang, Dongcheng; Bougri, Oleg

    2016-02-02

    Methods for consolidated pretreatment and hydrolysis of genetically engineered plants expressing cell wall degrading enzymes are provided. Expression cassettes and vectors for making transgenic plants are described. Plants engineered to express one or more cell wall degrading enzymes using expression cassettes and vectors of the invention are also provided.

  7. 78 FR 49528 - Consolidation of Wound Care Products Containing Live Cells

    Science.gov (United States)

    2013-08-14

    ... HUMAN SERVICES Food and Drug Administration Consolidation of Wound Care Products Containing Live Cells...) is transferring oversight responsibilities for certain wound care products containing live cells from... scientific and regulatory activities between CDRH and CBER. FDA believes that as more wound care...

  8. Biocalcifying Bacillus subtilis cells effectively consolidate deteriorated Globigerina limestone.

    Science.gov (United States)

    Micallef, Roderick; Vella, Daniel; Sinagra, Emmanuel; Zammit, Gabrielle

    2016-07-01

    Microbially induced calcite precipitation occurs naturally on ancient limestone surfaces in Maltese hypogea. We exploited this phenomenon and treated deteriorated limestone with biocalcifying bacteria. The limestone was subjected to various mechanical and physical tests to present a statistically robust data set to prove that treatment was indeed effective. Bacillus subtilis conferred uniform bioconsolidation to a depth of 30 mm. Drilling resistance values were similar to those obtained for freshly quarried limestone (9 N) and increased up to 15 N. Treatment resulted in a high resistance to salt deterioration and a slow rate of water absorption. The overall percentage porosity of treated limestone varied by ±6 %, thus the pore network was preserved. We report an eco-friendly treatment that closely resembles the mineral composition of limestone and that penetrates into the porous structure without affecting the limestones' natural properties. The treatment is of industrial relevance since it compares well with stone consolidants available commercially. PMID:27072564

  9. Industrialisation of polymer solar cells. Phase 2: Consolidation

    Energy Technology Data Exchange (ETDEWEB)

    Lauritzen, H.; Gevorgyan, S.; Frausig, J.; Andersen, Rasmus B.; Krebs, F.C.

    2013-03-15

    The key results from the project are: a firmly anchoring of DTU's basic polymer solar cell technology, ProcessOne, at Mekoprint, improved documented operational lifetime for polymer solar modules, and optimized processing of such modules. Mekoprint has worked determinedly to stabilize their production of ProcessOne devices, to prepare for full scale production and to build a marked for polymer solar cells. Work has been invested in improvement of process tolerances, documentation of the production process, training of process operators and roll-to-roll characterization of the produced solar cells. The planned and conducted actions have been summed up in a SIPOC diagram. Mekoprint's communication with potential customers reveals that lowering the cost, increasing the efficiency and operational life time is important for reaching the commercial market. Activities aimed at penetrating the market for lighting products in 3{sup rd} world countries are intensified. A new solar cell laser pointer is developed and a series of 2000 has been produced for the purpose of creating a commercial focus on polymer solar cells. DTU has established a characterization laboratory for organic photovoltaics (CLOP). The laboratory allows for real-time - and accelerated lifetime testing of solar cells both indoor and outdoor, and thus for the development of reliable methods for predicting life-time from accelerated testing. An operational lifetime of 2 years has, by means of the method, been documented for polymer solar modules encapsulated in a food-packaging barrier. Preliminary accelerated measurements on an equivalent device encapsulated in the same barrier, but in two layers, show a five times improvement of the solar cell stability. On basis of this it is considered that five years operational lifetime is within reach. DTU has improved of their OPV production technology by replacing the purchased vacuum-processed indium-tin-oxide (ITO) electrode by a roll-to-roll processed

  10. Notch-Mediated Cell Adhesion

    OpenAIRE

    Akihiko Murata; Shin-Ichi Hayashi

    2016-01-01

    Notch family members are generally recognized as signaling molecules that control various cellular responses in metazoan organisms. Early fly studies and our mammalian studies demonstrated that Notch family members are also cell adhesion molecules; however, information on the physiological roles of this function and its origin is limited. In this review, we discuss the potential present and ancestral roles of Notch-mediated cell adhesion in order to explore its origin and the initial roles of...

  11. Consolidative treatment after salvage chemotherapy improves prognosis in patients with relapsed extranodal natural killer/T-cell lymphoma

    OpenAIRE

    Man Nie; Xi-wen Bi; Wen-wen Zhang; Peng Sun; Yi Xia; Pan-pan Liu; Hui-qiang Huang; Wen-qi Jiang; Zhi-ming Li

    2016-01-01

    The optimal treatment strategy for relapsed natural killer/T-cell lymphoma (NKTCL) remains largely unknown. We retrospectively reviewed the treatment modalities and prognosis of 56 relapsed NKTCL patients. Chemotherapy was the initial salvage treatment, followed by radiotherapy (RT) or autologous hematopoietic stem cell transplantation (AHSCT) as consolidative therapy, depending on the status of remission and the pattern of relapse. For patients with locoregional relapse alone, consolidative ...

  12. Fungal-mediated consolidated bioprocessing: the potential of Fusarium oxysporum for the lignocellulosic ethanol industry.

    Science.gov (United States)

    Ali, Shahin S; Nugent, Brian; Mullins, Ewen; Doohan, Fiona M

    2016-03-01

    Microbial bioprocessing of lignocellulose to bioethanol still poses challenges in terms of substrate catabolism. The most important challenge is to overcome substrate recalcitrance and to thus reduce the number of steps needed to biorefine lignocellulose. Conventionally, conversion involves chemical pretreatment of lignocellulose, followed by hydrolysis of biomass to monomer sugars that are subsequently fermented into bioethanol. Consolidated bioprocessing (CBP) has been suggested as an efficient and economical method of manufacturing bioethanol from lignocellulose. CBP integrates the hydrolysis and fermentation steps into a single process, thereby significantly reducing the amount of steps in the biorefining process. Filamentous fungi are remarkable organisms that are naturally specialised in deconstructing plant biomass and thus they have tremendous potential as components of CBP. The fungus Fusarium oxysporum has potential for CBP of lignocellulose to bioethanol. Here we discuss the complexity and potential of CBP, the bottlenecks in the process, and the potential influence of fungal genetic diversity, substrate complexity and new technologies on the efficacy of CPB of lignocellulose, with a focus on F. oxysporum. PMID:26888202

  13. [Methylenetetrahydrofolate reductase polymorphism C677T in patients with consolidated fractures and pseudarthrosis of long bones: relationship with homocystein and inflammatory mediators].

    Science.gov (United States)

    Bezsmertnyĭ, Iu O

    2013-01-01

    In article described research the results of the prevalence of the genetic polymorphism of the gene Methylentetrahydrofolatereductase C677T (MTHFR) in 130 patients with pseudarthrosis of long bones and in those with consolidated fractures. The incidence of allele-T among patients with pseudarthrosis was 1.4 times higher than among those with consolidated fractures. Pathological genotype MTHFR 677-TT was associated with the development avital types of pseudarthrosis and increase the proportion of people with hyperhomocysteinemia, high content of inflammatory mediators and development refracture. PMID:24605633

  14. Benefit of Consolidative Radiation Therapy for Primary Bone Diffuse Large B-Cell Lymphoma

    Energy Technology Data Exchange (ETDEWEB)

    Tao, Randa; Allen, Pamela K. [Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Rodriguez, Alma [Department of Lymphoma and Myeloma, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Shihadeh, Ferial; Pinnix, Chelsea C.; Arzu, Isadora; Reed, Valerie K. [Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Oki, Yasuhiro; Westin, Jason R.; Fayad, Luis E.; Medeiros, L. Jeffrey [Department of Lymphoma and Myeloma, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Dabaja, Bouthaina, E-mail: bdabaja@mdanderson.org [Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States)

    2015-05-01

    Purpose: Outcomes for patients with diffuse large B-cell lymphoma (DLBCL) differ according to the site of presentation. With effective chemotherapy, the need for consolidative radiation therapy (RT) is controversial. We investigated the influence of primary bone presentation and receipt of consolidative RT on progression-free survival (PFS) and overall survival (OS) in patients with DLBCL. Methods and Materials: We identified 102 patients with primary bone DLBCL treated consecutively from 1988 through 2013 and extracted clinical, pathologic, and treatment characteristics from the medical records. Survival outcomes were calculated by the Kaplan-Meier method, with factors affecting survival determined by log-rank tests. Univariate and multivariate analyses were done with a Cox regression model. Results: The median age was 55 years (range, 16-87 years). The most common site of presentation was in the long bones. Sixty-five patients (63%) received R-CHOP–based chemotherapy, and 74 (72%) received rituximab. RT was given to 67 patients (66%), 47 with stage I to II and 20 with stage III to IV disease. The median RT dose was 44 Gy (range, 24.5-50 Gy). At a median follow-up time of 82 months, the 5-year PFS and OS rates were 80% and 82%, respectively. Receipt of RT was associated with improved 5-year PFS (88% RT vs 63% no RT, P=.0069) and OS (91% vs 68%, P=.0064). On multivariate analysis, the addition of RT significantly improved PFS (hazard ratio [HR] = 0.14, P=.014) with a trend toward an OS benefit (HR=0.30, P=.053). No significant difference in PFS or OS was found between patients treated with 30 to 35 Gy versus ≥36 Gy (P=.71 PFS and P=.31 OS). Conclusion: Patients with primary bone lymphoma treated with standard chemotherapy followed by RT can have excellent outcomes. The use of consolidative RT was associated with significant benefits in both PFS and OS.

  15. Current Research on Consolidation Therapy and Follow-up Health Care in Advanced Non-small Cell Lung Cancer Patients

    Institute of Scientific and Technical Information of China (English)

    Runbo Zhong; Baohui Han; Bo Jin

    2008-01-01

    ABSTRACT Following concurrent radio-chemotherapy or first-line chemotherapy for advanced non-small cell lung cancer(NSCLC), continuous maintenance therapy given to patients with stable disease (SD) and follow-up treatment is called consolidation therapy. Concerning NSCLC patients with a non-operable dry Stage-ⅢB (N3) disease, I.e. Contra-lateral mediastinal and hilar lymph node, or homolateral/contra-lateral scalene and Troisier sign, a 2 or 3-course of standard-dosage Taxotere consolidation therapy can be performed after concurrent radio-chemotherapy. In pursuance of evidence-based medicine (EBM), low-dose Taxoteremaintenance therapy, and biological targeted therapy of patients with appropriate symptoms are suitable for second-line therapy for moist of the Stage-ⅢB (malignant pleural effusion) and Ⅳpatients.

  16. Impact of postremission consolidation chemotherapy on outcome after reduced-intensity conditioning allogeneic stem cell transplantation for patients with acute myeloid leukemia in first complete remission

    DEFF Research Database (Denmark)

    Yeshurun, Moshe; Labopin, Myriam; Blaise, Didier;

    2014-01-01

    The objective of the current study was to investigate the role of postremission consolidation chemotherapy before reduced-intensity conditioning (RIC) allogeneic stem cell transplantation (alloSCT) for patients with acute myeloid leukemia (AML) in first complete remission (CR1).......The objective of the current study was to investigate the role of postremission consolidation chemotherapy before reduced-intensity conditioning (RIC) allogeneic stem cell transplantation (alloSCT) for patients with acute myeloid leukemia (AML) in first complete remission (CR1)....

  17. Two-Stage Translational Control of Dentate Gyrus LTP Consolidation Is Mediated by Sustained BDNF-TrkB Signaling to MNK

    Directory of Open Access Journals (Sweden)

    Debabrata Panja

    2014-11-01

    Full Text Available BDNF signaling contributes to protein-synthesis-dependent synaptic plasticity, but the dynamics of TrkB signaling and mechanisms of translation have not been defined. Here, we show that long-term potentiation (LTP consolidation in the dentate gyrus of live rodents requires sustained (hours BDNF-TrkB signaling. Surprisingly, this sustained activation maintains an otherwise labile signaling pathway from TrkB to MAP-kinase-interacting kinase (MNK. MNK activity promotes eIF4F translation initiation complex formation and protein synthesis in mechanistically distinct early and late stages. In early-stage translation, MNK triggers release of the CYFIP1/FMRP repressor complex from the 5′-mRNA cap. In late-stage translation, MNK regulates the canonical translational repressor 4E-BP2 in a synapse-compartment-specific manner. This late stage is coupled to MNK-dependent enhanced dendritic mRNA translation. We conclude that LTP consolidation in the dentate gyrus is mediated by sustained BDNF signaling to MNK and MNK-dependent regulation of translation in two functionally and mechanistically distinct stages.

  18. Extensive disease small cell carcinoma of the lung; trial of non-cross resistant chemotherapy and consolidation radiotherapy

    International Nuclear Information System (INIS)

    Twenty-nine patients with extensive disease, small-cell carcinoma of the lung, were treated with two cycles of intensive combination chemotherapy: HexaVAC (hexamethylmelamine, vincristine, Adriamycin, cyclophosphamide). Responders received prophylactic cranial radiation (2000 rad/10 fractions) and non cross resistant chemotherapy via a schedule of alternating cycles of CMV (cyclophosphamide, methotrexate, VP-16-213) and AMV (Adriamycin, methotrexate, VP-16-213). Whenever a complete response was achieved, consolidation radiotherapy was given to the lung primary (4000 rad/20 fractions, split dose) and abdominal metastases (2000 rad/10 fractions) synchronous with CMV therapy. The complete response rate was 14% with HexaVAC, but increased to 38% during CMV/AMV. Total response rate (complete and partial) was 59% and median survival was 42 weeks. Prophylactic brain radiation prevented clinical relapse in the brain in all 14 patients who received it. However, consolidation radiotherapy failed to prevent clinical relapse in the lung and/or liver, and therapeutic brain radiation (3000 rad) failed to prevent relapse in that site. The simultaneous administration of radiotherapy and chemotherapy was well-tolerated although two patients with poor performance status died of infectious complications while leukopenic. In spite of the high response rate, durable remissions with prolonged disease free survival were rare. Further evaluation of induction, consolidation, and maintenance modes of therapy are indicated

  19. Mast Cell-Mediated Mechanisms of Nociception

    Science.gov (United States)

    Aich, Anupam; Afrin, Lawrence B.; Gupta, Kalpna

    2015-01-01

    Mast cells are tissue-resident immune cells that release immuno-modulators, chemo-attractants, vasoactive compounds, neuropeptides and growth factors in response to allergens and pathogens constituting a first line of host defense. The neuroimmune interface of immune cells modulating synaptic responses has been of increasing interest, and mast cells have been proposed as key players in orchestrating inflammation-associated pain pathobiology due to their proximity to both vasculature and nerve fibers. Molecular underpinnings of mast cell-mediated pain can be disease-specific. Understanding such mechanisms is critical for developing disease-specific targeted therapeutics to improve analgesic outcomes. We review molecular mechanisms that may contribute to nociception in a disease-specific manner. PMID:26690128

  20. MicroRNA-mediated somatic cell reprogramming.

    Science.gov (United States)

    Kuo, Chih-Hao; Ying, Shao-Yao

    2013-02-01

    Since the first report of induced pluripotent stem cells (iPSCs) using somatic cell nuclear transfer (SCNT), much focus has been placed on iPSCs due to their great therapeutic potential for diseases such as abnormal development, degenerative disorders, and even cancers. Subsequently, Takahashi and Yamanaka took a novel approach by using four defined transcription factors to generate iPSCs in mice and human fibroblast cells. Scientists have since been trying to refine or develop better approaches to reprogramming, either by using different combinations of transcription factors or delivery methods. However, recent reports showed that the microRNA expression pattern plays a crucial role in somatic cell reprogramming and ectopic introduction of embryonic stem cell-specific microRNAs revert cells back to an ESC-like state, although, the exact mechanism underlying this effect remains unclear. This review describes recent work that has focused on microRNA-mediated approaches to somatic cell reprogramming as well as some of the pros and cons to these approaches and a possible mechanism of action. Based on the pivotal role of microRNAs in embryogenesis and somatic cell reprogramming, studies in this area must continue in order to gain a better understanding of the role of microRNAs in stem cells regulation and activity. PMID:22961769

  1. Mediated Electrochemical Measurements of Intracellular Catabolic Activities of Yeast Cells

    Institute of Scientific and Technical Information of China (English)

    Jin Sheng ZHAO; Zhen Yu YANG; Yao LU; Zheng Yu YANG

    2005-01-01

    Coupling with the dual mediator system menadione/ferricyanide, microelectrode voltammetric measurements were undertaken to detect the ferrocyanide accumulations arising from the mediated reduction of ferricyanide by yeast cells. The results indicate that the dual mediator system menadione/ferricyanide could be used as a probe to detect cellular catabolic activities in yeast cells and the electrochemical response has a positive relationship with the specific growth rate of yeast cells.

  2. Impact of Consolidation Radiation Therapy in Stage III-IV Diffuse Large B-cell Lymphoma With Negative Post-Chemotherapy Radiologic Imaging

    Energy Technology Data Exchange (ETDEWEB)

    Dorth, Jennifer A., E-mail: jennifer.dorth@duke.edu [Department of Radiation Oncology, Duke University Medical Center, Durham, North Carolina (United States); Prosnitz, Leonard R. [Department of Radiation Oncology, Duke University Medical Center, Durham, North Carolina (United States); Broadwater, Gloria [Cancer Statistical Center, Duke University Medical Center, Durham, North Carolina (United States); Diehl, Louis F.; Beaven, Anne W. [Department of Medicine, Division of Medical Oncology, Duke University Medical Center, Durham, North Carolina (United States); Coleman, R. Edward [Department of Radiology, Division of Nuclear Medicine, Duke University Medical Center, Durham, North Carolina (United States); Kelsey, Chris R. [Department of Radiation Oncology, Duke University Medical Center, Durham, North Carolina (United States)

    2012-11-01

    Purpose: While consolidation radiation therapy (i.e., RT administered after chemotherapy) is routine treatment for patients with early-stage diffuse large B-cell lymphoma (DLBCL), the role of consolidation RT in stage III-IV DLBCL is controversial. Methods and Materials: Cases of patients with stage III-IV DLBCL treated from 1991 to 2009 at Duke University, who achieved a complete response to chemotherapy were reviewed. Clinical outcomes were calculated using the Kaplan-Meier method and were compared between patients who did and did not receive RT, using the log-rank test. A multivariate analysis was performed using Cox proportional hazards model. Results: Seventy-nine patients were identified. Chemotherapy (median, 6 cycles) consisted of anti-CD20 antibody rituximab combined with cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP; 65%); cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP; 22%); or other (13%). Post-chemotherapy imaging consisted of positron emission tomography (PET)/computed tomography (CT) (73%); gallium with CT (14%); or CT only (13%). Consolidation RT (median, 25 Gy) was given to involved sites of disease in 38 (48%) patients. Receipt of consolidation RT was associated with improved in-field control (92% vs. 69%, respectively, p = 0.028) and event-free survival (85% vs. 65%, respectively, p = 0.014) but no difference in overall survival (85% vs. 78%, respectively, p = 0.15) when compared to patients who did not receive consolidation RT. On multivariate analysis, no RT was predictive of increased risk of in-field failure (hazard ratio [HR], 8.01, p = 0.014) and worse event-free survival (HR, 4.3, p = 0.014). Conclusions: Patients with stage III-IV DLBCL who achieve negative post-chemotherapy imaging have improved in-field control and event-free survival with low-dose consolidation RT.

  3. Oncogenic BRAF-Mediated Melanoma Cell Invasion

    Directory of Open Access Journals (Sweden)

    Hezhe Lu

    2016-05-01

    Full Text Available Melanoma patients with oncogenic BRAFV600E mutation have poor prognoses. While the role of BRAFV600E in tumorigenesis is well established, its involvement in metastasis that is clinically observed in melanoma patients remains a topic of debate. Here, we show that BRAFV600E melanoma cells have extensive invasion activity as assayed by the generation of F-actin and cortactin foci that mediate membrane protrusion, and degradation of the extracellular matrix (ECM. Inhibition of BRAFV600E blocks melanoma cell invasion. In a BRAFV600E-driven murine melanoma model or in patients’ tumor biopsies, cortactin foci decrease upon inhibitor treatment. In addition, genome-wide expression analysis shows that a number of invadopodia-related genes are downregulated after BRAFV600E inhibition. Mechanistically, BRAFV600E induces phosphorylation of cortactin and the exocyst subunit Exo70 through ERK, which regulates actin dynamics and matrix metalloprotease secretion, respectively. Our results provide support for the role of BRAFV600E in metastasis and suggest that inhibiting invasion is a potential therapeutic strategy against melanoma.

  4. Nanomedicine-mediated cancer stem cell therapy.

    Science.gov (United States)

    Shen, Song; Xia, Jin-Xing; Wang, Jun

    2016-01-01

    Circumstantial evidence suggests that most tumours are heterogeneous and contain a small population of cancer stem cells (CSCs) that exhibit distinctive self-renewal, proliferation and differentiation capabilities, which are believed to play a crucial role in tumour progression, drug resistance, recurrence and metastasis in multiple malignancies. Given that the existence of CSCs is a primary obstacle to cancer therapy, a tremendous amount of effort has been put into the development of anti-CSC strategies, and several potential approaches to kill therapeutically-resistant CSCs have been explored, including inhibiting ATP-binding cassette transporters, blocking essential signalling pathways involved in self-renewal and survival of CSCs, targeting CSCs surface markers and destroying the tumour microenvironment. Meanwhile, an increasing number of therapeutic agents (e.g. small molecule drugs, nucleic acids and antibodies) to selectively target CSCs have been screened or proposed in recent years. Drug delivery technology-based approaches hold great potential for tackling the limitations impeding clinical applications of CSC-specific agents, such as poor water solubility, short circulation time and inconsistent stability. Properly designed nanocarrier-based therapeutic agents (or nanomedicines) offer new possibilities of penetrating CSC niches and significantly increasing therapeutic drug accumulation in CSCs, which are difficult for free drug counterparts. In addition, intelligent nanomedicine holds great promise to overcome pump-mediated multidrug resistance which is driven by ATP and to decrease detrimental effects on normal somatic stem cells. In this review, we summarise the distinctive biological processes related to CSCs to highlight strategies against inherently drug-resistant CSCs. We then focus on some representative examples that give a glimpse into state-of-the-art nanomedicine approaches developed for CSCs elimination. A perspective on innovative therapeutic

  5. Inflammatory mediators: Parallels between cancer biology and stem cell therapy

    OpenAIRE

    Patel, Shyam A; Heinrich, Andrew C; Bobby Y. Reddy; Rameshwar, Pranela

    2009-01-01

    Inflammation encompasses diverse molecular pathways, and it is intertwined with a wide array of biological processes. Recently, there has been an upsurge of interest in the interactions between mediators of inflammation and other cells such as stem cells and cancer cells. Since tissue injuries are associated with the release of inflammatory mediators, it would be difficult to address this subject without considering the implications of their systemic effects. In this review, we discuss the ef...

  6. Sustained First Remission in an Adolescent With Hepatosplenic T-Cell Lymphoma Treated With T-Cell Leukemia Induction, Nucleoside Analog-Based Consolidation, and Early Hematopoietic Stem Cell Transplant

    OpenAIRE

    Schafer, Eric; Chen, Allen; Arceci, Robert J.

    2009-01-01

    Hepatosplenic T-cell lymphoma (HTCL) is a rare malignancy. Prognosis is poor with only a few case reports of long-term survivors. While HTCL universally involves the bone marrow, the condition has been most often treated with multimodal lymphoma specific chemotherapy. We report a durable, sustained first remission in an adolescent treated for HTCL who received induction therapy according to a high risk T-cell leukemia regimen, a nucleoside analog-based consolidation, and allogeneic transplant...

  7. The L-Type Voltage-Gated Calcium Channel Ca[subscript v]1.3 Mediates Consolidation, but Not Extinction, of Contextually Conditioned Fear in Mice

    Science.gov (United States)

    McKinney, Brandon C.; Murphy, Geoffrey G.

    2006-01-01

    Using pharmacological techniques, it has been demonstrated that both consolidation and extinction of Pavlovian fear conditioning are dependent to some extent upon L-type voltage-gated calcium channels (LVGCCs). Although these studies have successfully implicated LVGCCs in Pavlovian fear conditioning, they do not provide information about the…

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

    Directory of Open Access Journals (Sweden)

    Wataru Sonoyama

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

  9. GILT - A randomised phase III study of oral vinorelbine and cisplatin with concomitant radiotherapy followed by either consolidation therapy with oral vinorelbine and cisplatin or best supportive care alone in stage III non-small cell lung cancer

    International Nuclear Information System (INIS)

    Concurrent chemoradiotherapy (CRT) is considered standard for inoperable stage III non-small cell lung cancer (NSCLC). Consolidation chemotherapy (CC) following CRT is intended to further improve outcomes, yet studies have shown discordant results. This phase III study assessed CRT followed by best supportive care (BSC) or consolidation with oral vinorelbine and cisplatin. Patients received two cycles of oral vinorelbine (50 mg/m2 days 1, 8 and 15) + cisplatin (20 mg/m2 days 1-4) q4w + radiotherapy (RT; 66 Gy). Patients with at least stable disease (SD) were randomised to either two cycles oral vinorelbine (60-80 mg/m2 days 1 and 8) + cisplatin (80 mg/m2 day 1) q3w + BSC or BSC alone. Primary endpoint was progression-free survival (PFS). A total of 279 patients were enrolled for CRT and 201 patients were randomised to CC or BSC. Both CRT and CC were well tolerated, with limited radiation-mediated grade 3/4 toxicities (CRT/CC/BSC: oesophagitis-related events 12.9 %/3.1 %/0 %; grade 3 pneumonitis 0 %/0 %/2 %) and chemotherapy-mediated grade 3/4 toxicities (CRT/CC: neutropenia 11.2 %/22.1 %; leukopenia 18.3 %/26.7 %; grade 3 nausea 5.0 %/2.3 %, grade 3 vomiting 3.2 %/3.5 %). Median PFS from randomisation was 6.4 (5.0-8.7) and 5.5 (3.8-7.4) months in the CC and BSC arms (hazard ratio, HR = 0.93 [0.69-1.26]; p = 0.63), respectively; median overall survival (OS) 20.8 (13.5-25.3) and 18.5 (13.6-24.7) months, respectively. Consolidation chemotherapy after concurrent CRT did not prolong PFS or OS. Concurrent RT with oral vinorelbine and cisplatin demonstrated a favourable safety profile and represents a suitable treatment regimen for inoperable stage III NSCLC. (orig.)

  10. Mesenchymal Stem Cell-Mediated Functional Tooth Regeneration in Swine

    OpenAIRE

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

    2006-01-01

    Mesenchymal stem cell-mediated tissue regeneration is a promising approach for regenerative medicine for a wide range of applications. Here we report a new population of stem cells isolated from the root apical papilla of human teeth (SCAP, stem cells from apical papilla). Using a minipig model, we transplanted both human SCAP and periodontal ligament stem cells (PDLSCs) to generate a root/periodontal complex capable of supporting a porcelain crown, resulting in normal tooth function. This wo...

  11. Fuel consolidation demonstration: Consolidation concept development

    Energy Technology Data Exchange (ETDEWEB)

    1990-02-01

    EPRI, Northeast utilities Service Company (NUSCO), DOE, Baltimore Gas Electric Company, and Combustion Engineering, Inc. (C-E) are engaged in a program to develop a system for consolidating spent fuel, in which the consolidated fuel will be licensable by NRC for storage in the spent-fuel storage pool. Fuel consolidation offers a means of substantially increasing the capacity of spent-fuel storage pools. Consolidation equipment design, development, construction, and testing are being performed by C-E in Windsor, Connecticut. Seismic and structural evaluation of the capability of the Millstone Unit 2 spent-fuel pool and building to accommodate the increased fuel capacity is being conducted by NUSCO. NUSCO plans to obtain a license to store consolidated fuel in the Millstone-2 spent-fuel storage pool. NUSCO also plans to perform a hot demonstration of the integrated consolidation system with spent fuel at Millstone-2. This report describes the consolidation system design that forms the basis for the detailed design of the equipment comprising the system, including information on the fabrication and testing of the equipment. Appendix B describes an evaluation of the ability of the system under development to consolidate LWR spent-fuel assemblies other than the 14 {times} 14 fuel of C-E design stored at Millstone-2. A comparison was made of fuel-assembly designs on the basis of information available in open literature. It was concluded that with appropriate dimensional modifications the spent-fuel consolidation system equipment design is applicable to almost all PWR fuel-assembly configurations. 8 refs., 20 figs.

  12. Polycation-mediated integrated cell death processes

    DEFF Research Database (Denmark)

    Parhamifar, Ladan; Andersen, Helene; Wu, Linping;

    2014-01-01

    standard. PEIs are highly efficient transfectants, but depending on their architecture and size they induce cytotoxicity through different modes of cell death pathways. Here, we briefly review dynamic and integrated cell death processes and pathways, and discuss considerations in cell death assay design...

  13. Cdc42-mediated tubulogenesis controls cell specification

    DEFF Research Database (Denmark)

    Kesavan, Gokul; Sand, Fredrik Wolfhagen; Greiner, Thomas Uwe;

    2009-01-01

    Understanding how cells polarize and coordinate tubulogenesis during organ formation is a central question in biology. Tubulogenesis often coincides with cell-lineage specification during organ development. Hence, an elementary question is whether these two processes are independently controlled......, or whether proper cell specification depends on formation of tubes. To address these fundamental questions, we have studied the functional role of Cdc42 in pancreatic tubulogenesis. We present evidence that Cdc42 is essential for tube formation, specifically for initiating microlumen formation and later...... for maintaining apical cell polarity. Finally, we show that Cdc42 controls cell specification non-cell-autonomously by providing the correct microenvironment for proper control of cell-fate choices of multipotent progenitors. For a video summary of this article, see the PaperFlick file with the Supplemental Data...

  14. Multifactorial aspects of antibody-mediated blood cell destruction

    NARCIS (Netherlands)

    R. Kapur

    2014-01-01

    The research described in this thesis focuses on diseases of antibody-mediated blood cell destruction via FcγRs on phagocytes, in particular regarding platelets in fetal or neonatal alloimmune thrombocytopenia (FNAIT) and red blood cells (RBC) in hemolytic disease of the fetus and newborn (HDFN). Di

  15. Bone marrow stromal cell: mediated neuroprotection for spinal cord repair

    OpenAIRE

    Ritfeld, Gaby Jane

    2014-01-01

    Currently, there is no treatment available that restores anatomy and function after spinal cord injury. This thesis explores transplantation of bone marrow-derived mesenchymal stem cells (bone marrow stromal cells; BMSCs) as a therapeutic approach for spinal cord repair. BMSCs secrete neurotrophic factors, enabling neuroprotection/tissue sparing in a rat model of spinal cord injury. In this model system, bone marrow stromal cell-mediated tissue sparing leads to motor and sensory function impr...

  16. Ion mediated targeting of cells with nanoparticles

    Science.gov (United States)

    Maheshwari, Vivek; Fu, Jinlong

    2010-03-01

    In eukaryotic cells, Ca^2+ ions are necessary for intracellular signaling, in activity of mitochondria and a variety of other cellular process that have been linked to cell apoptosis, proteins synthesis and cell-cycle regulation. Here we show that Ca^2+ ions, serving as the bio-compatible interface can be used to target Saccharomyces cerevisiae (SaC, baker's yeast), a model eukaryotic cell, with Au nanoparticles (10 nm). The Ca^2+ ions bind to the carboxylic acid groups in the citrate functionalized Au nanoparticles. This transforms the nanoparticles into micron long 1-D branched chain assemblies due to inter-particle dipole-dipole interaction and inter-particle bonding due to the divalent nature of the Ca^2+ ion. A similar transformation is observed with the use of divalent ions Mg^2+, Cd^2+ and Fe^2+. The 1-D assembly aids the interfacing of ion-nanoparticles on the cell by providing multiple contact points. Further monovalent ions such as Na^+ are also effective for the targeting of the cell with nanoparticles. However Na-Au nanoparticles are limited in their deposition as they exist in solution as single particles. The cells remain alive after the deposition process and their vitality is unaffected by the interfacing with ion-nanoparticles.

  17. Laser-mediated perforation of plant cells

    Science.gov (United States)

    Wehner, Martin; Jacobs, Philipp; Esser, Dominik; Schinkel, Helga; Schillberg, Stefan

    2007-07-01

    The functional analysis of plant cells at the cellular and subcellular levels requires novel technologies for the directed manipulation of individual cells. Lasers are increasingly exploited for the manipulation of plant cells, enabling the study of biological processes on a subcellular scale including transformation to generate genetically modified plants. In our setup either a picosecond laser operating at 1064 nm wavelength or a continuous wave laser diode emitting at 405 nm are coupled into an inverse microscope. The beams are focused to a spot size of about 1.5 μm and the tobacco cell protoplasts are irradiated. Optoporation is achieved when targeting the laser focal spot at the outermost edge of the plasma membrane. In case of the picosecond laser a single pulse with energy of about 0.4 μJ was sufficient to perforate the plasma membrane enabling the uptake of dye or DNA from the surrounding medium into the cytosol. When the ultraviolet laser diode at a power level of 17 mW is employed an irradiation time of 200 - 500 milliseconds is necessary to enable the uptake of macromolecules. In the presence of an EYFP encoding plasmid with a C-terminal peroxisomal signal sequence in the surrounding medium transient transformation of tobacco protoplasts could be achieved in up to 2% of the optoporated cells. Single cell perforation using this novel optoporation method shows that isolated plant cells can be permeabilized without direct manipulation. This is a valuable procedure for cell-specific applications, particularly where the import of specific molecules into plant cells is required for functional analysis.

  18. Acquired cancer stem cell phenotypes through Oct4-mediated dedifferentiation

    Science.gov (United States)

    Kumar, Suresh M.; Liu, Shujing; Lu, Hezhe; Zhang, Hongtao; Zhang, Paul J.; Gimotty, Phyllis A.; Guerra, Matthew; Guo, Wei; Xu, Xiaowei

    2012-01-01

    There is enormous interest to target cancer stem cells (CSCs) for clinical treatment because these cells are highly tumorigenic and resistant to chemotherapy. Oct4 is expressed by CSC-like cells in different types of cancer. However, function of Oct4 in tumor cells is unclear. In this study, we showed that expression of Oct4 gene or transmembrane delivery of Oct4 protein promoted dedifferentiation of melanoma cells to CSC-like cells. The dedifferentiated melanoma cells showed significantly decreased expression of melanocytic markers and acquired the ability to form tumor spheroids. They showed markedly increased resistance to chemotherapeutic agents and hypoxic injury. In the subcutaneous xenograft and tail vein injection assays, these cells had significantly increased tumorigenic capacity. The dedifferentiated melanoma cells acquired features associated with CSCs such as multipotent differentiation capacity and expression of melanoma CSC markers such as ABCB5 and CD271. Mechanistically, Oct4 induced dedifferentiation was associated with increased expression of endogenous Oct4, Nanog and Klf4, and global gene expression changes that enriched for transcription factors. RNAi mediated knockdown of Oct4 in dedifferentiated cells led to diminished CSC phenotypes. Oct4 expression in melanoma was regulated by hypoxia and its expression was detected in a subpopulation of melanoma cells in clinical samples. Our data indicate that Oct4 is a positive regulator of tumor dedifferentiation. The results suggest that CSC phenotype is dynamic and may be acquired through dedifferentiation. Oct4 mediated tumor cell dedifferentiation may play an important role during tumor progression. PMID:22286766

  19. Cortactin mediated morphogenic cell movements during zebrafish (Danio rerio) gastrulation

    Institute of Scientific and Technical Information of China (English)

    YU Dan; ZHANG Peijun; ZHAN Xi

    2005-01-01

    Cell migration is essential to direct embryonic cells to specific sites at which their developmental fates are ultimately determined. However, the mechanism by which cell motility is regulated in embryonic development is largely unknown. Cortactin, a filamentous actin binding protein, is an activator of Arp2/3 complex in the nucleation of actin cytoskeleton at the cell leading edge and acts directly on the machinery of cell motility. To determine whether cortactin and Arp2/3 mediated actin assembly plays a role in the morphogenic cell movements during the early development of zebrafish, we initiated a study of cortactin expression in zebrafish embryos at gastrulating stages when massive cell migrations occur. Western blot analysis using a cortactin specific monoclonal antibody demonstrated that cortactin protein is abundantly present in embryos at the most early developmental stages. Immunostaining of whole-mounted embryo showed that cortactin immunoreactivity was associated with the embryonic shield, predominantly at the dorsal side of the embryos during gastrulation. In addition, cortactin was detected in the convergent cells of the epiblast and hypoblast, and later in the central nervous system. Immunofluorescent staining with cortactin and Arp3 antibodies also revealed that cortactin and Arp2/3 complex colocalized at the periphery and many patches associated with the cell-to-cell junction in motile embryonic cells. Therefore, our data suggest that cortactin and Arp2/3 mediated actin polymerization is implicated in the cell movement during gastrulation and perhaps the development of the central neural system as well.

  20. Glioma cell dispersion is driven by α5 integrin-mediated cell-matrix and cell-cell interactions.

    Science.gov (United States)

    Blandin, Anne-Florence; Noulet, Fanny; Renner, Guillaume; Mercier, Marie-Cécile; Choulier, Laurence; Vauchelles, Romain; Ronde, Philippe; Carreiras, Franck; Etienne-Selloum, Nelly; Vereb, Gyorgy; Lelong-Rebel, Isabelle; Martin, Sophie; Dontenwill, Monique; Lehmann, Maxime

    2016-07-01

    Glioblastoma multiform (GBM) is the most common and most aggressive primary brain tumor. The fibronectin receptor, α5 integrin is a pertinent novel therapeutic target. Despite numerous data showing that α5 integrin support tumor cell migration and invasion, it has been reported that α5 integrin can also limit cell dispersion by increasing cell-cell interaction. In this study, we showed that α5 integrin was involved in cell-cell interaction and gliomasphere formation. α5-mediated cell-cell cohesion limited cell dispersion from spheroids in fibronectin-poor microenvironment. However, in fibronectin-rich microenvironment, α5 integrin promoted cell dispersion. Ligand-occupied α5 integrin and fibronectin were distributed in fibril-like pattern at cell-cell junction of evading cells, forming cell-cell fibrillar adhesions. Activated focal adhesion kinase was not present in these adhesions but was progressively relocalized with α5 integrin as cell migrates away from the spheroids. α5 integrin function in GBM appears to be more complex than previously suspected. As GBM overexpressed fibronectin, it is most likely that in vivo, α5-mediated dissemination from the tumor mass overrides α5-mediated tumor cell cohesion. In this respect, α5-integrin antagonists may be useful to limit GBM invasion in brain parenchyma. PMID:27063097

  1. Cell-mediated mutagenesis and cell transformation of mammalian cells by chemical carcinogens

    International Nuclear Information System (INIS)

    We have developed a cell-mediated mutagenesis assay in which cells with the appropriate markers for mutagenesis are co-cultivated with either lethally irradiated rodent embryonic cells that can metabolize carcinogenic hydrocarbons or with primary rat liver cells that can metabolize chemicals carcinogenic to the liver. During co-cultivation, the reactive metabolites of the procarcinogen appear to be transmitted to the mutable cells and induce mutations in them. Assays of this type make it possible to demonstrate a relationship between carcinogenic potency of the chemicals and their ability to induce mutations in mammalian cells. In addition, by simultaneously comparing the frequencies of transformation and mutation induced in normal diploid hamster cells by benzo(a)pyrene (BP) and one of its metabolites, it is possible to estimate the genetic target size for cell transformation in vitro

  2. Simultaneous consolidation and creep

    DEFF Research Database (Denmark)

    Krogsbøll, Anette

    1997-01-01

    Materials that exhibit creep under constant effective stress typically also show rate dependent behavior. The creep deformations and the rate sensitive behavior is very important when engineering and geological problems with large time scales are considered. When stress induced compaction...... (consolidation) is retarded by slow drainage of excess pore pressure it is expected that consolidation and creep occur simultaneously. A constitutive model adressing the problems of rate sensitive behavior and simultaneous consolidation and creep is presented....

  3. Parathyroid hormone mediates hematopoietic cell expansion through interleukin-6.

    Directory of Open Access Journals (Sweden)

    Flavia Q Pirih

    Full Text Available Parathyroid hormone (PTH stimulates hematopoietic cells through mechanisms of action that remain elusive. Interleukin-6 (IL-6 is upregulated by PTH and stimulates hematopoiesis. The purpose of this investigation was to identify actions of PTH and IL-6 in hematopoietic cell expansion. Bone marrow cultures from C57B6 mice were treated with fms-like tyrosine kinase-3 ligand (Flt-3L, PTH, Flt-3L plus PTH, or vehicle control. Flt-3L alone increased adherent and non-adherent cells. PTH did not directly impact hematopoietic or osteoclastic cells but acted in concert with Flt-3L to further increase cell numbers. Flt-3L alone stimulated proliferation, while PTH combined with Flt-3L decreased apoptosis. Flt-3L increased blasts early in culture, and later increased CD45(+ and CD11b(+ cells. In parallel experiments, IL-6 acted additively with Flt-3L to increase cell numbers and IL-6-deficient bone marrow cultures (compared to wildtype controls but failed to amplify in response to Flt-3L and PTH, suggesting that IL-6 mediated the PTH effect. In vivo, PTH increased Lin(- Sca-1(+c-Kit(+ (LSK hematopoietic progenitor cells after PTH treatment in wildtype mice, but failed to increase LSKs in IL-6-deficient mice. In conclusion, PTH acts with Flt-3L to maintain hematopoietic cells by limiting apoptosis. IL-6 is a critical mediator of bone marrow cell expansion and is responsible for PTH actions in hematopoietic cell expansion.

  4. Stem cell  mediated liver regeneration:

    DEFF Research Database (Denmark)

    Jelnes, Peter

    udformet en strategi som involverede isolering af HPCr vha. Fluorescent Activated Cell Sorting (FACS). Isolerede celler skulle efterfølgende undersøges ved in vitro studier som implicerede tilsætning af specifikke immunrespons relaterede faktorer. Kun få specifikke overflade HPC markører er blevet...

  5. Intratumoral oxygen gradients mediate sarcoma cell invasion.

    Science.gov (United States)

    Lewis, Daniel M; Park, Kyung Min; Tang, Vitor; Xu, Yu; Pak, Koreana; Eisinger-Mathason, T S Karin; Simon, M Celeste; Gerecht, Sharon

    2016-08-16

    Hypoxia is a critical factor in the progression and metastasis of many cancers, including soft tissue sarcomas. Frequently, oxygen (O2) gradients develop in tumors as they grow beyond their vascular supply, leading to heterogeneous areas of O2 depletion. Here, we report the impact of hypoxic O2 gradients on sarcoma cell invasion and migration. O2 gradient measurements showed that large sarcoma mouse tumors (>300 mm(3)) contain a severely hypoxic core [≤0.1% partial pressure of O2 (pO2)] whereas smaller tumors possessed hypoxic gradients throughout the tumor mass (0.1-6% pO2). To analyze tumor invasion, we used O2-controllable hydrogels to recreate the physiopathological O2 levels in vitro. Small tumor grafts encapsulated in the hydrogels revealed increased invasion that was both faster and extended over a longer distance in the hypoxic hydrogels compared with nonhypoxic hydrogels. To model the effect of the O2 gradient accurately, we examined individual sarcoma cells embedded in the O2-controllable hydrogel. We observed that hypoxic gradients guide sarcoma cell motility and matrix remodeling through hypoxia-inducible factor-1α (HIF-1α) activation. We further found that in the hypoxic gradient, individual cells migrate more quickly, across longer distances, and in the direction of increasing O2 tension. Treatment with minoxidil, an inhibitor of hypoxia-induced sarcoma metastasis, abrogated cell migration and matrix remodeling in the hypoxic gradient. Overall, we show that O2 acts as a 3D physicotactic agent during sarcoma tumor invasion and propose the O2-controllable hydrogels as a predictive system to study early stages of the metastatic process and therapeutic targets. PMID:27486245

  6. Predictors of Local Recurrence After Rituximab-Based Chemotherapy Alone in Stage III and IV Diffuse Large B-Cell Lymphoma: Guiding Decisions for Consolidative Radiation

    Energy Technology Data Exchange (ETDEWEB)

    Jegadeesh, Naresh; Rajpara, Raj; Esiashvili, Natia; Shi, Zheng [Department of Radiation Oncology, Emory University, Atlanta, Georgia (United States); Winship Cancer Institute, Emory University, Atlanta, Georgia (United States); Liu, Yuan [Winship Cancer Institute, Emory University, Atlanta, Georgia (United States); Department of Biostatistics and Bioinformatics Shared Resource, Emory University, Atlanta, Georgia (United States); Okwan-Duodu, Derrick [Department of Radiation Oncology, Emory University, Atlanta, Georgia (United States); Winship Cancer Institute, Emory University, Atlanta, Georgia (United States); Flowers, Christopher R. [Winship Cancer Institute, Emory University, Atlanta, Georgia (United States); Department of Medical Oncology, Emory University, Atlanta, Georgia (United States); Khan, Mohammad K., E-mail: drkhurram2000@gmail.com [Department of Radiation Oncology, Emory University, Atlanta, Georgia (United States); Winship Cancer Institute, Emory University, Atlanta, Georgia (United States)

    2015-05-01

    Purpose: The role of consolidative radiation therapy (RT) for stage III and IV diffuse large B-cell lymphoma (DLBCL) in the era of rituximab is not well defined. There is evidence that some patients with bulky disease may benefit, but patient selection criteria are not well established. We sought to identify a subset of patients who experienced a high local failure rate after receiving rituximab-based chemotherapy alone and hence may benefit from the addition of consolidative RT. Methods and Materials: Two hundred eleven patients with stage III and IV DLBCL treated between August 1999 and January 2012 were reviewed. Of these, 89 had a complete response to systemic therapy including rituximab and received no initial RT. Kaplan-Meier analysis and Cox proportional hazards regression were performed, with local recurrence (LR) as the primary outcome. Results: The median follow-up time was 43.9 months. Fifty percent of patients experienced LR at 5 years. In multivariate analysis, tumor ≥5 cm and stage III disease were associated with increased risk of LR. The 5-year LR-free survival was 47.4% for patients with ≥5-cm lesions versus 74.7% for patients with <5-cm lesions (P=.01). In patients with <5-cm tumors, the maximum standardized uptake value (SUVmax) was ≥15 in all patients with LR. The 5-year LR-free survival was 100% in SUV<15 versus 68.8% in SUV≥15 (P=.10). Conclusions: Advanced-stage DLBCL patients with stage III disease or with disease ≥5 cm appear to be at an increased risk for LR. Patients with <5-cm disease and SUVmax ≥15 may be at higher risk for LR. These patients may benefit from consolidative RT after chemoimmunotherapy.

  7. Cell mediated immunity to fungi: a reassessment.

    Science.gov (United States)

    Romani, Luigina

    2008-09-01

    Protective immunity against fungal pathogens is achieved by the integration of two distinct arms of the immune system, the innate and adaptive responses. Innate and adaptive immune responses are intimately linked and controlled by sets of molecules and receptors that act to generate the most effective form of immunity for protection against fungal pathogens. The decision of how to respond will still be primarily determined by interactions between pathogens and cells of the innate immune system, but the actions of T cells will feed back into this dynamic equilibrium to regulate the balance between tolerogenic and inflammatory responses. In the last two decades, the immunopathogenesis of fungal infections and fungal diseases was explained primarily in terms of Th1/Th2 balance. Although Th1 responses driven by the IL-12/IFN-gamma axis are central to protection against fungi, other cytokines and T cell-dependent pathways have come of age. The newly described Th17 developmental pathway may play an inflammatory role previously attributed to uncontrolled Th1 responses and serves to accommodate the seemingly paradoxical association of chronic inflammatory responses with fungal persistence in the face of an ongoing inflammation. Regulatory T cells in their capacity to inhibit aspects of innate and adaptive antifungal immunity have become an integral component of immune resistance to fungi, and provide the host with immune defense mechanisms adequate for protection, without necessarily eliminating fungal pathogens which would impair immune memory--or causing an unacceptable level of tissue damage. The enzyme indoleamine 2,3-dioxygenase and tryptophan metabolites contribute to immune homeostasis by inducing Tregs and taming overzealous or heightened inflammatory responses.

  8. Biomarkers of CD4+ CTL cell Mediated Immunity to Tuberculosis

    Science.gov (United States)

    The immune responses mediated by interactions between T-lymphocyte subsets and mycobacteria-infected macrophages are critical for control of tuberculosis. In these studies, the bovine model was used to characterize the cytolytic and mycobactericidal CD4+ T cell response induced by BCG vaccination. ...

  9. Multifactorial aspects of antibody-mediated blood cell destruction

    OpenAIRE

    Schoot, van der, B.H.; Vidarsson, G.; Kapur, R.

    2014-01-01

    The research described in this thesis focuses on diseases of antibody-mediated blood cell destruction via FcγRs on phagocytes, in particular regarding platelets in fetal or neonatal alloimmune thrombocytopenia (FNAIT) and red blood cells (RBC) in hemolytic disease of the fetus and newborn (HDFN). Diagnostically, for HDFN laboratory tests are in place in order to predict risk for severe fetal RBC destruction and thereby initiate appropriate treatments. This test is sensitive, but has relativel...

  10. Defective cell mediated immunity in sarcoidosis: effect of interleukin-2.

    OpenAIRE

    Lyons, D J; Gao, L.; Mitchell, E B; Mitchell, D. N.

    1988-01-01

    Interleukin-2 has been reported to enhance the immune response in diseases characterised by defective cell mediated immunity. The effect of exogenous recombinant interleukin-2 was studied on the proliferative and cytotoxic responses of peripheral blood mononuclear cells from 39 patients with sarcoidosis and 14 healthy control subjects. The proliferative response to purified protein derivative was smaller in patients than in control subjects (p less than 0.001) whereas the response to 80 U int...

  11. Inflammatory mediators: Parallels between cancer biology and stem cell therapy

    Directory of Open Access Journals (Sweden)

    A Patel

    2009-02-01

    Full Text Available Shyam A Patel1,2,3, Andrew C Heinrich2,3, Bobby Y Reddy2, Pranela Rameshwar21Graduate School of Biomedical Sciences, University of Medicine and Dentistry of New Jersey, Newark, NJ, USA; 2Department of Medicine – Division of Hematology/Oncology, New Jersey Medical School, University of Medicine and Dentistry of New Jersey, Newark, NJ, USA; 3These authors contributed equally to this workAbstract: Inflammation encompasses diverse molecular pathways, and it is intertwined with a wide array of biological processes. Recently, there has been an upsurge of interest in the interactions between mediators of inflammation and other cells such as stem cells and cancer cells. Since tissue injuries are associated with the release of inflammatory mediators, it would be difficult to address this subject without considering the implications of their systemic effects. In this review, we discuss the effects of inflammatory reactions on stem cells and extrapolate on information pertaining to cancer biology. The discussion focuses on integrins and cytokines, and identifies the transcription factor, nuclear factor-kappa B (NFκB as central to the inflammatory response. Since stem cell therapy has been proposed for type II diabetes mellitus, metabolic syndrome, pulmonary edema, these disorders are used as examples to discuss the roles of inflammatory mediators. We propose prospects for future research on targeting the NFκB signaling pathway. Finally, we explore the bridge between inflammation and stem cells, including neural stem cells and adult stem cells from the bone marrow. The implications of mesenchymal stem cells in regenerative medicine as pertaining to inflammation are vast based on their anti-inflammatory and immunosuppressive effects. Such features of stem cells offer great potential for therapy in graft-versus-host disease, conditions with a significant inflammatory component, and tissue regeneration.Keywords: mesenchymal stem cells, cancer, cytokines

  12. Neural stem cell-derived exosomes mediate viral entry

    Directory of Open Access Journals (Sweden)

    Sims B

    2014-10-01

    Full Text Available Brian Sims,1,2,* Linlin Gu,3,* Alexandre Krendelchtchikov,3 Qiana L Matthews3,4 1Division of Neonatology, Department of Pediatrics, 2Department of Cell, Developmental, and Integrative Biology, 3Division of Infectious Diseases, Department of Medicine, 4Center for AIDS Research, University of Alabama at Birmingham, Birmingham, AL, USA *These authors contributed equally to this work Background: Viruses enter host cells through interactions of viral ligands with cellular receptors. Viruses can also enter cells in a receptor-independent fashion. Mechanisms regarding the receptor-independent viral entry into cells have not been fully elucidated. Exosomal trafficking between cells may offer a mechanism by which viruses can enter cells.Methods: To investigate the role of exosomes on cellular viral entry, we employed neural stem cell-derived exosomes and adenovirus type 5 (Ad5 for the proof-of-principle study. Results: Exosomes significantly enhanced Ad5 entry in Coxsackie virus and adenovirus receptor (CAR-deficient cells, in which Ad5 only had very limited entry. The exosomes were shown to contain T-cell immunoglobulin mucin protein 4 (TIM-4, which binds phosphatidylserine. Treatment with anti-TIM-4 antibody significantly blocked the exosome-mediated Ad5 entry.Conclusion: Neural stem cell-derived exosomes mediated significant cellular entry of Ad5 in a receptor-independent fashion. This mediation may be hampered by an antibody specifically targeting TIM-4 on exosomes. This set of results will benefit further elucidation of virus/exosome pathways, which would contribute to reducing natural viral infection by developing therapeutic agents or vaccines. Keywords: neural stem cell-derived exosomes, adenovirus type 5, TIM-4, viral entry, phospholipids

  13. Mast cell-derived histamine mediates cystitis pain.

    Directory of Open Access Journals (Sweden)

    Charles N Rudick

    Full Text Available BACKGROUND: Mast cells trigger inflammation that is associated with local pain, but the mechanisms mediating pain are unclear. Interstitial cystitis (IC is a bladder disease that causes debilitating pelvic pain of unknown origin and without consistent inflammation, but IC symptoms correlate with elevated bladder lamina propria mast cell counts. We hypothesized that mast cells mediate pelvic pain directly and examined pain behavior using a murine model that recapitulates key aspects of IC. METHODS AND FINDINGS: Infection of mice with pseudorabies virus (PRV induces a neurogenic cystitis associated with lamina propria mast cell accumulation dependent upon tumor necrosis factor alpha (TNF, TNF-mediated bladder barrier dysfunction, and pelvic pain behavior, but the molecular basis for pelvic pain is unknown. In this study, both PRV-induced pelvic pain and bladder pathophysiology were abrogated in mast cell-deficient mice but were restored by reconstitution with wild type bone marrow. Pelvic pain developed normally in TNF- and TNF receptor-deficient mice, while bladder pathophysiology was abrogated. Conversely, genetic or pharmacologic disruption of histamine receptor H1R or H2R attenuated pelvic pain without altering pathophysiology. CONCLUSIONS: These data demonstrate that mast cells promote cystitis pain and bladder pathophysiology through the separable actions of histamine and TNF, respectively. Therefore, pain is independent of pathology and inflammation, and histamine receptors represent direct therapeutic targets for pain in IC and other chronic pain conditions.

  14. Cell-Cell Interactions Mediate the Response of Vascular Smooth Muscle Cells to Substrate Stiffness

    Science.gov (United States)

    Sazonova, Olga V.; Lee, Kristen L.; Isenberg, Brett C.; Rich, Celeste B.; Nugent, Matthew A.; Wong, Joyce Y.

    2011-01-01

    The vessel wall experiences progressive stiffening with age and the development of cardiovascular disease, which alters the micromechanical environment experienced by resident vascular smooth muscle cells (VSMCs). In vitro studies have shown that VSMCs are sensitive to substrate stiffness, but the exact molecular mechanisms of their response to stiffness remains unknown. Studies have also shown that cell-cell interactions can affect mechanotransduction at the cell-substrate interface. Using flexible substrates, we show that the expression of proteins associated with cell-matrix adhesion and cytoskeletal tension is regulated by substrate stiffness, and that an increase in cell density selectively attenuates some of these effects. We also show that cell-cell interactions exert a strong effect on cell morphology in a substrate-stiffness dependent manner. Collectively, the data suggest that as VSMCs form cell-cell contacts, substrate stiffness becomes a less potent regulator of focal adhesion signaling. This study provides insight into the mechanisms by which VSMCs respond to the mechanical environment of the blood vessel wall, and point to cell-cell interactions as critical mediators of VSMC response to vascular injury. PMID:21806930

  15. Single cell migration dynamics mediated by geometric confinement.

    Science.gov (United States)

    Zhang, Hua; Hou, Ruixia; Xiao, Peng; Xing, Rubo; Chen, Tao; Han, Yanchun; Ren, Penggang; Fu, Jun

    2016-09-01

    The migration dynamics of cells plays a key role in tissue engineering and regenerative medicine. Previous studies mostly focus on regulating stem cell fate and phenotype by biophysical cues. In contrast, less is known about how the geometric cues mediate the migration dynamics of cells. Here, we fabricate graphene oxide (GO) microstripes on cell non-adhesive PEG substrate by using micromolding in capillary (MIMIC) method. Such micropatterns with alternating cell adhesion and cell resistance enable an effective control of selective adhesion and migration of single cells. The sharp contrast in cell adhesion minimizes the invasion of cells into the PEG patterns, and thereby strongly confines the cells on GO microstripes. As a result, the cells are forced to adapt highly polarized, elongated, and oriented geometry to fit the patterns. A series of pattern widths have been fabricated to modulate the extent of cell deformation and polarization. Under strong confinement, the cytoskeleton contractility, intracellular traction, and actin filament elongation are highly promoted, which result in enhanced cell migration along the patterns. This work provides an important insight into developing combinatorial graphene-based patterns for the control of cell migration dynamics, which is of great significance for tissue engineering and regenerative medicine. PMID:27137805

  16. Consolidation Radiotherapy in Stage IE- IIE, Non-Bulky Primary Gastric Diffuse Large B-Cell Lymphoma with Post-Chemotherapy Complete Remission.

    Directory of Open Access Journals (Sweden)

    Qiwen Li

    Full Text Available To investigate the effects of consolidation radiation in patients with stage IE-IIE, non-bulky primary gastric diffuse large B-cell lymphoma (DLBCL.A cohort consisted of 71 consecutive patients with stage IE-IIE, non-bulky primary gastric DLBCL was retrospectively analyzed. All of them had been in complete remission after receiving at least four cycles of chemotherapy, containing rituximab or not. Consolidation radiation was delivered thereafter in 28 patients while other 43 received clinical observation only. Locoregional relapse-free survival (LRFS, disease-free survival (DFS, overall survival (OS and distant metastasis-free survival (DMFS were compared between patients with or without radiotherapy.The 10-year LRFS, DFS, OS and DMFS were 100% and 81.4% (p = 0.028, 91.7% and 77.1% (p = 0.14, 91.7% and 77.8% (p = 0.67, 91.7% and 78.0% (p = 0.42 for patients with or without radiotherapy.Radiotherapy is associated with improved locoregional control of patients with early stage primary gastric DLBCL, who have achieved complete remission following at least four cycles of chemotherapy.

  17. Cytolysis of oligodendrocytes is mediated by killer (K) cells but not by natural killer (NK) cells.

    Science.gov (United States)

    Satoh, J; Kim, S U; Kastrukoff, L F

    1991-03-01

    The cytotoxic activity of killer (K) cells against enriched cultures of bovine oligodendrocytes (BOL) was investigated in multiple sclerosis (MS) and controls. Human K cells mediated cytotoxicity to primary cultures of BOL in the presence of anti-BOL antiserum in all study groups, while BOL were resistant to human natural killer (NK) cells. Cytotoxic activity was significantly reduced in MS when compared to age-matched normal controls but not when compared to other neurologic disease (OND) patients. K cell-mediated lysis of BOL could also be induced with anti-galactocerebroside antibody but not with other antibodies including those specific for OL antigens (myelin basic protein, proteolipid apoprotein, and 2',3'-cyclic nucleotide 3'-phosphodiesterase). Enrichment of the effector population indicated that antibody-dependent cell-mediated cytotoxicity (ADCC) to BOL was mediated by large granular lymphocytes, and the effector population was further characterized by flow cytometry. The effector cells mediating ADCC could be inhibited by protein A of Staphylococcus aureus, and by K562 cells in cold competition assay. These observations indicate that oligodendrocytes are resistant to NK cells but are susceptible to cytolysis mediated by K cells. This may represent a potentially important immune mechanism in the pathogenesis of MS.

  18. MAR characteristic motifs mediate episomal vector in CHO cells.

    Science.gov (United States)

    Lin, Yan; Li, Zhaoxi; Wang, Tianyun; Wang, Xiaoyin; Wang, Li; Dong, Weihua; Jing, Changqin; Yang, Xianjun

    2015-04-01

    An ideal gene therapy vector should enable persistent transgene expression without limitations in safety and reproducibility. Recent researches' insight into the ability of chromosomal matrix attachment regions (MARs) to mediate episomal maintenance of genetic elements allowed the development of a circular episomal vector. Although a MAR-mediated engineered vector has been developed, little is known on which motifs of MAR confer this function during interaction with the host genome. Here, we report an artificially synthesized DNA fragment containing only characteristic motif sequences that served as an alternative to human beta-interferon matrix attachment region sequence. The potential of the vector to mediate gene transfer in CHO cells was investigated. The short synthetic MAR motifs were found to mediate episomal vector at a low copy number for many generations without integration into the host genome. Higher transgene expression was maintained for at least 4 months. In addition, MAR was maintained episomally and conferred sustained EGFP expression even in nonselective CHO cells. All the results demonstrated that MAR characteristic sequence-based vector can function as stable episomes in CHO cells, supporting long-term and effective transgene expression.

  19. HIGH EFFICIENCY RETROVIRUS-MEDIATED GENE TRANSFER TO LEUKEMIA CELLS

    Institute of Scientific and Technical Information of China (English)

    FU Jian-xin; CHEN Zi-xing; CEN Jian-nong; WANG Wei; RUAN Chang-geng

    1999-01-01

    Objective: To establish an efficient and safe gene transfer system mediated by retrovirus for gene marking and gene therapy of human leukemia. Method: The retroviral vector LXSN, containing the neomycin resistance (NeoR) gene, was transferred into amphotropic packaging cells GP+envAm12 by liposome transfection or by ecotropic retrovirus transduction. Amphotropic retrovirus in supernatants with higher titer was used to infect human leukemic cell lines NB4, U937, and THP-1.The efficiency of gene transfer was assayed on colonies formed by transduced K562 cells. Results: The titer of DOSPER directly transfected GP+envAm12 cells determined on NIH3T3 cells was 8.0×105 CFU/ml, while that of producer infected with retrovirus was 1.6×107CFU/ml. Integration of NeoR gene into all leukemia cells was confirmed by polymerase chain reaction (PCR).Absence of replication-competent virus was proved by both nested PCR for env gene and marker gene rescue assay. Gene transfer with the efficiency as high as 93.3 to 100% in K562 cells was verified by seminested PCR for integrated NeoR gene on colonies after 7 days' culture.Conclusion: The efficiency and safety of retrovirus mediated gene transfer system might provide an optimal system in gene therapy for leukemia or genetic diseases.

  20. Stress-mediated p38 activation promotes somatic cell reprogramming

    Institute of Scientific and Technical Information of China (English)

    Xinxiu Xu; Quan Wang; Yuan Long; Ru Zhang; Xiaoyuan Wei; Mingzhe Xing; Haifeng Gu

    2013-01-01

    Environmental stress-mediated adaptation plays essential roles in the evolution of life.Cellular adaptation mechanisms usually involve the regulation of chromatin structure,transcription,mRNA stability and translation,which eventually lead to efficient changes in gene expression.Global epigenetic change is also involved in the reprogramming of somatic cells into induced pluripotent stem (iPS) cells by defined factors.Here we report that environmental stress such as hyperosmosis not only facilitates four factor-mediated reprogramming,but also enhances two or one factor-induced iPS cell generation.Hyperosmosis-induced p38 activation plays a critical role in this process.Constitutive active p38 mimics the positive effect of hyperosmosis,while dominant negative p38 and p38 inhibitor block the effect of hyperosmosis.Further study indicates stress-mediated p38 activation may promote reprogramming by reducing the global DNA methylation level and enhancing the expression of pluripotency genes.Our results demonstrate how simple environmental stress like hyperosmosis helps to alter the fate of cells via intracellular signaling and epigenetic modulation.

  1. Peripheral and central CB1 cannabinoid receptors control stress-induced impairment of memory consolidation.

    Science.gov (United States)

    Busquets-Garcia, Arnau; Gomis-González, Maria; Srivastava, Raj Kamal; Cutando, Laura; Ortega-Alvaro, Antonio; Ruehle, Sabine; Remmers, Floortje; Bindila, Laura; Bellocchio, Luigi; Marsicano, Giovanni; Lutz, Beat; Maldonado, Rafael; Ozaita, Andrés

    2016-08-30

    Stressful events can generate emotional memories linked to the traumatic incident, but they also can impair the formation of nonemotional memories. Although the impact of stress on emotional memories is well studied, much less is known about the influence of the emotional state on the formation of nonemotional memories. We used the novel object-recognition task as a model of nonemotional memory in mice to investigate the underlying mechanism of the deleterious effect of stress on memory consolidation. Systemic, hippocampal, and peripheral blockade of cannabinoid type-1 (CB1) receptors abolished the stress-induced memory impairment. Genetic deletion and rescue of CB1 receptors in specific cell types revealed that the CB1 receptor population specifically in dopamine β-hydroxylase (DBH)-expressing cells is both necessary and sufficient for stress-induced impairment of memory consolidation, but CB1 receptors present in other neuronal populations are not involved. Strikingly, pharmacological manipulations in mice expressing CB1 receptors exclusively in DBH(+) cells revealed that both hippocampal and peripheral receptors mediate the impact of stress on memory consolidation. Thus, CB1 receptors on adrenergic and noradrenergic cells provide previously unrecognized cross-talk between central and peripheral mechanisms in the stress-dependent regulation of nonemotional memory consolidation, suggesting new potential avenues for the treatment of cognitive aspects on stress-related disorders. PMID:27528659

  2. Regulatory T cells in immune-mediated renal disease.

    Science.gov (United States)

    Ghali, Joanna R; Wang, Yuan Min; Holdsworth, Stephen R; Kitching, A Richard

    2016-02-01

    Regulatory T cells (Tregs) are CD4+ T cells that can suppress immune responses by effector T cells, B cells and innate immune cells. This review discusses the role that Tregs play in murine models of immune-mediated renal diseases and acute kidney injury and in human autoimmune kidney disease (such as systemic lupus erythematosus, anti-glomerular basement membrane disease, anti-neutrophil cytoplasmic antibody-associated vasculitis). Current research suggests that Tregs may be reduced in number and/or have impaired regulatory function in these diseases. Tregs possess several mechanisms by which they can limit renal and systemic inflammatory immune responses. Potential therapeutic applications involving Tregs include in vivo induction of Tregs or inducing Tregs from naïve CD4+ T cells or expanding natural Tregs ex vivo, to use as a cellular therapy. At present, the optimal method of generating a phenotypically stable pool of Tregs with long-lasting suppressive effects is not established, but human studies in renal transplantation are underway exploring the therapeutic potential of Tregs as a cellular therapy, and if successful may have a role as a novel therapy in immune-mediated renal diseases. PMID:26206106

  3. The role of cell-mediated immunity in typhoid.

    Science.gov (United States)

    Mabel, T J; Paniker, C K

    1979-06-01

    The cell-mediated immunity in typhoid was assessed by the leukocyte migration inhibition test and delayed hypersensitivity skin test in 60 clinical typhoid patients. The property of leukocyte migration inhibition appeared first and was positive in 28 of 60 (46.7%) patients on admission and 45 of 60 (75%) at the time of discharge. This difference was definitely more in blood culture positive patients. The delayed hypersensitivity appeared later and was positive in 18 of 60 (30%) on admission and 31 of 60 (51.7%) at the time of discharge. Patients with positive cellular-immune response against typhoid antigen did not develop relapse. On the whole cell-mediated immunity seems to play an important role in typoid. The control groups--the medical and surgical patients, doctors, clinical students and preclinical students--showed positive cellular immune response of 43.3 81.3, 40.7 and 25% respectively. The significance of these results is discussed.

  4. Nanodrug-Mediated Thermotherapy of Cancer Stem-Like Cells.

    Science.gov (United States)

    Rao, Wei; Wang, Hai; Zhong, Allison; Yu, Jianhua; Lu, Xiongbin; He, Xiaoming

    2016-03-01

    Cancer stem-like cells (CSCs) are rare subpopulations of cancer cells that are resistant to conventional chemotherapy and radiotherapy and contribute to cancer metastases and tumor recurrence. Therefore, it is of significance to develop an effective therapy to eliminate the CSCs. Cancer thermotherapy realized by depositing heat into tumor in a minimally invasive way is a promising alternative to the conventional therapies for cancer treatment. However, this method is limited by its inability to target CSCs, potentially allowing the CSCs to survive and re-initiate tumor growth. More recently, nanodrug-mediated thermotherapy has been explored to selectively eliminate CSCs and specifically deposit heat in tumor to spare healthy tissue. Here, we provide a brief overview of the targeting moieties and nanoplatforms used in developing nanodrug-mediated thermotherapy of cancer with particular emphasis on the CSCs, as well as the challenges and potential directions for future research in this emerging field. PMID:27455612

  5. Roles of Cortactin, an Actin Polymerization Mediator, in Cell Endocytosis

    Institute of Scientific and Technical Information of China (English)

    Li CHEN; Zhi-Wei WANG; Jian-wei ZHU; Xi ZHAN

    2006-01-01

    Cortactin, an actin-binding protein and a substrate of Src, is encoded by the EMS 1 oncogene.Cortactin is known to activate Arp2/3 complex-mediated actin polymerization and interact with dynamin, a large GTPase and proline rich domain-containing protein. Transferrin endocytosis was significantly reduced in cells by knock-down of cortactin expression as well as in vivo introduction of cortactin immunoreagents.Cortactin-dynamin interaction displayed morphologically dynamic co-distribution with a change in the endocytosis level in cells treated with an actin depolymerization reagent, cytochalasin D. In an in vitro beads assay, a branched actin network was recruited onto dynamin-coated beads in a cortactin Src homology domain 3 (SH3)-dependent manner. In addition, cortactin was found to function in the late stage of clathrin coated vesicle formation.Taken together, cortactin is required for optimal clathrin mediated endocytosis in a dynamin directed manner.

  6. Computed Tomography-Based Anatomic Assessment Overestimates Local Tumor Recurrence in Patients With Mass-like Consolidation After Stereotactic Body Radiotherapy for Early-Stage Non-Small Cell Lung Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Dunlap, Neal E. [Department of Radiation Oncology, University of Louisville, Louisville, KY (United States); Yang Wensha [Department of Radiation Oncology, Cedars Sinai Medical Center, Los Angeles, CA (United States); McIntosh, Alyson [Department of Radiation Oncology, John and Dorothy Morgan Cancer Center, Lehigh Valley Hospital, Allentown, PA (United States); Sheng, Ke [Department of Radiation Oncology, David Geffen School of Medicine at University of California Los Angeles, Los Angeles, CA (United States); Benedict, Stanley H.; Read, Paul W. [Department of Radiation Oncology, University of Virginia, Charlottesville, VA (United States); Larner, James M., E-mail: jml2p@virginia.edu [Department of Radiation Oncology, University of Virginia, Charlottesville, VA (United States)

    2012-12-01

    Purpose: To investigate pulmonary radiologic changes after lung stereotactic body radiotherapy (SBRT), to distinguish between mass-like fibrosis and tumor recurrence. Methods and Materials: Eighty consecutive patients treated with 3- to 5-fraction SBRT for early-stage peripheral non-small cell lung cancer with a minimum follow-up of 12 months were reviewed. The mean biologic equivalent dose received was 150 Gy (range, 78-180 Gy). Patients were followed with serial CT imaging every 3 months. The CT appearance of consolidation was defined as diffuse or mass-like. Progressive disease on CT was defined according to Response Evaluation Criteria in Solid Tumors 1.1. Positron emission tomography (PET) CT was used as an adjunct test. Tumor recurrence was defined as a standardized uptake value equal to or greater than the pretreatment value. Biopsy was used to further assess consolidation in select patients. Results: Median follow-up was 24 months (range, 12.0-36.0 months). Abnormal mass-like consolidation was identified in 44 patients (55%), whereas diffuse consolidation was identified in 12 patients (15%), at a median time from end of treatment of 10.3 months and 11.5 months, respectively. Tumor recurrence was found in 35 of 44 patients with mass-like consolidation using CT alone. Combined with PET, 10 of the 44 patients had tumor recurrence. Tumor size (hazard ratio 1.12, P=.05) and time to consolidation (hazard ratio 0.622, P=.03) were predictors for tumor recurrence. Three consecutive increases in volume and increasing volume at 12 months after treatment in mass-like consolidation were highly specific for tumor recurrence (100% and 80%, respectively). Patients with diffuse consolidation were more likely to develop grade {>=}2 pneumonitis (odds ratio 26.5, P=.02) than those with mass-like consolidation (odds ratio 0.42, P=.07). Conclusion: Incorporating the kinetics of mass-like consolidation and PET to the current criteria for evaluating posttreatment response will

  7. Molecular Signaling Pathways Mediating Osteoclastogenesis Induced by Prostate Cancer Cells

    International Nuclear Information System (INIS)

    Advanced prostate cancer commonly metastasizes to bone leading to osteoblastic and osteolytic lesions. Although an osteolytic component governed by activation of bone resorbing osteoclasts is prominent in prostate cancer metastasis, the molecular mechanisms of prostate cancer-induced osteoclastogenesis are not well-understood. We studied the effect of soluble mediators released from human prostate carcinoma cells on osteoclast formation from mouse bone marrow and RAW 264.7 monocytes. Soluble factors released from human prostate carcinoma cells significantly increased viability of naïve bone marrow monocytes, as well as osteoclastogenesis from precursors primed with receptor activator of nuclear factor κ-B ligand (RANKL). The prostate cancer-induced osteoclastogenesis was not mediated by RANKL as it was not inhibited by osteoprotegerin (OPG). However inhibition of TGFβ receptor I (TβRI), or macrophage-colony stimulating factor (MCSF) resulted in attenuation of prostate cancer-induced osteoclastogenesis. We characterized the signaling pathways induced in osteoclast precursors by soluble mediators released from human prostate carcinoma cells. Prostate cancer factors increased basal calcium levels and calcium fluctuations, induced nuclear localization of nuclear factor of activated t-cells (NFAT)c1, and activated prolonged phosphorylation of ERK1/2 in RANKL-primed osteoclast precursors. Inhibition of calcium signaling, NFATc1 activation, and ERK1/2 phosphorylation significantly reduced the ability of prostate cancer mediators to stimulate osteoclastogenesis. This study reveals the molecular mechanisms underlying the direct osteoclastogenic effect of prostate cancer derived factors, which may be beneficial in developing novel osteoclast-targeting therapeutic approaches

  8. Factors influencing ER subtype-mediated cell proliferation and apoptosis

    OpenAIRE

    Evers, N.M.

    2014-01-01

      The aim of the current thesis is to elucidate the role of estrogen receptor (ER)αand ERβin cell proliferation and apoptosis induced by estrogenic compounds. Special attention is paid to the importance of the receptor preference of the estrogenic compounds, the cellular ERα/ERβratio, the role of coregulators, and ER-mediated induction of protein expression. In chapter 1 estrogenic compounds and their interaction with estrogen receptors are described and the two dif...

  9. Fibronectin on the Surface of Myeloma Cell-derived Exosomes Mediates Exosome-Cell Interactions.

    Science.gov (United States)

    Purushothaman, Anurag; Bandari, Shyam Kumar; Liu, Jian; Mobley, James A; Brown, Elizabeth E; Sanderson, Ralph D

    2016-01-22

    Exosomes regulate cell behavior by binding to and delivering their cargo to target cells; however, the mechanisms mediating exosome-cell interactions are poorly understood. Heparan sulfates on target cell surfaces can act as receptors for exosome uptake, but the ligand for heparan sulfate on exosomes has not been identified. Using exosomes isolated from myeloma cell lines and from myeloma patients, we identify exosomal fibronectin as a key heparan sulfate-binding ligand and mediator of exosome-cell interactions. We discovered that heparan sulfate plays a dual role in exosome-cell interaction; heparan sulfate on exosomes captures fibronectin, and on target cells it acts as a receptor for fibronectin. Removal of heparan sulfate from the exosome surface releases fibronectin and dramatically inhibits exosome-target cell interaction. Antibody specific for the Hep-II heparin-binding domain of fibronectin blocks exosome interaction with tumor cells or with marrow stromal cells. Regarding exosome function, fibronectin-mediated binding of exosomes to myeloma cells activated p38 and pERK signaling and expression of downstream target genes DKK1 and MMP-9, two molecules that promote myeloma progression. Antibody against fibronectin inhibited the ability of myeloma-derived exosomes to stimulate endothelial cell invasion. Heparin or heparin mimetics including Roneparstat, a modified heparin in phase I trials in myeloma patients, significantly inhibited exosome-cell interactions. These studies provide the first evidence that fibronectin binding to heparan sulfate mediates exosome-cell interactions, revealing a fundamental mechanism important for exosome-mediated cross-talk within tumor microenvironments. Moreover, these results imply that therapeutic disruption of fibronectin-heparan sulfate interactions will negatively impact myeloma tumor growth and progression.

  10. CONSOLIDATION OF MOTOR MEMORY

    OpenAIRE

    Krakauer, John W.; Shadmehr, Reza

    2005-01-01

    A question of great recent interest is whether motor memory consolidates in a manner analogous to declarative memories, with the formation of a memory that progresses over time from a fragile state, susceptible to interference by a lesion or a conflicting motor task, to a stabilized state, resistant to such interference. Here, we first review studies that examine the anatomical basis for motor consolidation: evidence implicates cerebellar circuitry for two types of associative motor learning,...

  11. B-cell-mediated strategies to fight chronic allograft rejection

    Directory of Open Access Journals (Sweden)

    Ali H Dalloul

    2013-12-01

    Full Text Available Solid organs have been transplanted for decades. Since the improvement in graft selection and in medical and surgical procedures, the likelihood of graft function after one year is now close to 90%. Nonetheless even well-matched recipients continue to need medications for the rest of their lives hence adverse side effects and enhanced morbidity. Understanding Immune rejection mechanisms, is of increasing importance since the greater use of living-unrelated donors and genetically unmatched individuals. Chronic rejection is devoted to T-cells, however the role of B-cells in rejection has been appreciated recently by the observation that B-cell depletion improve graft survival. By contrast however, B-cells can be beneficial to the grafted tissue. This protective effect is secondary to either the secretion of protective antibodies or the induction of B-cells that restrain excessive inflammatory responses, chiefly by local provision of IL-10, or inhibit effector T-cells by direct cellular interactions. As a proof of concept B-cell-mediated infectious transplantation tolerance could be achieved in animal models, and evidence emerged that the presence of such B-cells in transplanted patients correlate with a favorable outcome. Among these populations, regulatory B-cells constitute a recently described population. These cells may develop as a feedback mechanism to prevent uncontrolled reactivity to antigens and inflammatory stimuli. The difficult task for the clinician, is to quantify the respective ratios and functions of tolerant vs effector B-cells within a transplanted organ, at a given time point in order to modulate B-cell-directed therapy. Several receptors at the B-cell membrane as well as signaling molecules, can now be targeted for this purpose. Understanding the temporal expansion of regulatory B-cells in grafted patients and the stimuli that activate them will help in the future to implement specific strategies aimed at fighting chronic

  12. Sphingosine kinase-1 mediates androgen-induced osteoblast cell growth

    Energy Technology Data Exchange (ETDEWEB)

    Martin, Claire [CNRS, Institut de Pharmacologie et de Biologie Structurale, Toulouse F-31000 (France); Universite de Toulouse, UPS, IPBS, Toulouse F-31000 (France); Lafosse, Jean-Michel [CHU Toulouse, Hopital Rangueil, Service d' orthopedie et Traumatologie, Toulouse F-31000 (France); Malavaud, Bernard [CNRS, Institut de Pharmacologie et de Biologie Structurale, Toulouse F-31000 (France); Universite de Toulouse, UPS, IPBS, Toulouse F-31000 (France); CHU Toulouse, Hopital Rangueil, Service d' Urologie et de Transplantation Renale, Toulouse F-31000 (France); Cuvillier, Olivier, E-mail: olivier.cuvillier@ipbs.fr [CNRS, Institut de Pharmacologie et de Biologie Structurale, Toulouse F-31000 (France); Universite de Toulouse, UPS, IPBS, Toulouse F-31000 (France)

    2010-01-01

    Herein we report that the lipid kinase sphingosine kinase-1 (SphK1) is instrumental in mediating androgen-induced cell proliferation in osteoblasts. Dihydrotestosterone (DHT) triggered cell growth in steroid-deprived MC3T3 cells, which was associated with a rapid stimulation of SphK1 and activation of both Akt and ERK signaling pathways. This mechanism relied on functional androgen receptor/PI3K/Akt nongenotropic signaling as pharmacological antagonists could block SphK1 stimulation by DHT and its consequences. Finally, SphK1 inhibition not only abrogated DHT-induced ERK activation but also blocked cell proliferation, while ERK inhibition had no impact, suggesting that SphK1 was critical for DHT signaling yet independently of the ERK.

  13. DNA-mediated gene transfer into ataxia-telangiectasia cells

    International Nuclear Information System (INIS)

    The complete description of the genetic lesion(s) underlying the AT mutation might, therefore, highlight not only a DNA-repair pathwa, but also an important aspect of the physiology of lymphocytes. DNA-mediated gene transfer into eukaryotic cells has proved a powerful tool for the molecular cloning of certain mammalian genes. The possibility to clone a given gene using this technology depends, basically, on the availability of a selectable marker associated with the expression of the transfected gene in the recipient cell. Recently, a human DNA repair gene has been cloned in CHO mutant cells by taking advantage of the increased resistance to ultraviolet radiation of the transformants. As a preliminary step toward the molecular cloning of the AT gene(s), the authors have attempted to confer radioresistance to AT cells by transfection with normal human DNA

  14. Nonlinear Finite Strain Consolidation Analysis with Secondary Consolidation Behavior

    OpenAIRE

    Jieqing Huang; Xinyu Xie; Jifa Zhang; Jinzhu Li; Wenjun Wang

    2014-01-01

    This paper aims to analyze nonlinear finite strain consolidation with secondary consolidation behavior. On the basis of some assumptions about the secondary consolidation behavior, the continuity equation of pore water in Gibson’s consolidation theory is modified. Taking the nonlinear compressibility and nonlinear permeability of soils into consideration, the governing equation for finite strain consolidation analysis is derived. Based on the experimental data of Hangzhou soft clay samples, t...

  15. Recruitment and Consolidation of Cell Assemblies for Words by Way of Hebbian Learning and Competition in a Multi-Layer Neural Network.

    Science.gov (United States)

    Garagnani, Max; Wennekers, Thomas; Pulvermüller, Friedemann

    2009-06-01

    Current cognitive theories postulate either localist representations of knowledge or fully overlapping, distributed ones. We use a connectionist model that closely replicates known anatomical properties of the cerebral cortex and neurophysiological principles to show that Hebbian learning in a multi-layer neural network leads to memory traces (cell assemblies) that are both distributed and anatomically distinct. Taking the example of word learning based on action-perception correlation, we document mechanisms underlying the emergence of these assemblies, especially (i) the recruitment of neurons and consolidation of connections defining the kernel of the assembly along with (ii) the pruning of the cell assembly's halo (consisting of very weakly connected cells). We found that, whereas a learning rule mapping covariance led to significant overlap and merging of assemblies, a neurobiologically grounded synaptic plasticity rule with fixed LTP/LTD thresholds produced minimal overlap and prevented merging, exhibiting competitive learning behaviour. Our results are discussed in light of current theories of language and memory. As simulations with neurobiologically realistic neural networks demonstrate here spontaneous emergence of lexical representations that are both cortically dispersed and anatomically distinct, both localist and distributed cognitive accounts receive partial support.

  16. A mediação do riso na expressão e consolidação racismo no Brasil The laughter as a mediator of the expression and consolidation of racism in Brazil

    Directory of Open Access Journals (Sweden)

    Sandra Leal de Melo Dahia

    2008-12-01

    Full Text Available O objetivo do presente artigo é fornecer uma possível leitura da realidade do racismo no Brasil, na qual o riso desempenha um importante papel mediador. Inscrito na fronteira entre realidades distintas - o psíquico e o social, o consciente e o inconsciente, o jocoso e o sério -, o riso, suscitado pela piada racista, é capaz de articulá-las de forma a contribuir para o encobrimento e a consolidação do racismo aqui vigente. O efeito de sua ação pode soçobrar em conseqüência de um debate público em que o próprio riso se torne o objeto da discussão.This article aims at providing a possible reading of the reality of racism in Brazil in which laughter plays a relevant mediating role. Inserted among distinct realities - psychic and social, conscious and unconscious, playful and serious -, the laughter, as a by-product of racist jokes, can articulate these realities in such a manner as to contribute to concealing and consolidating the existing racism in Brazil. Its effect may be obscured as a consequence of a public debate in which laughter itself becomes the object of the discussion.

  17. Protein Kinase G facilitates EGFR-mediated cell death in MDA-MB-468 cells.

    Science.gov (United States)

    Jackson, Nicole M; Ceresa, Brian P

    2016-08-15

    The Epidermal Growth Factor Receptor (EGFR) is a transmembrane receptor tyrosine kinase with critical implications in cell proliferation, migration, wound healing and the regulation of apoptosis. However, the EGFR has been shown to be hyper-expressed in a number of human malignancies. The MDA-MB-468 metastatic breast cell line is one example of this. This particular cell line hyper-expresses the EGFR and undergoes EGFR-mediated apoptosis in response to EGF ligand. The goal of this study was to identify the kinases that could be potential intermediates for the EGFR-mediated induction of apoptosis intracellularly. After identifying Cyclic GMP-dependent Protein Kinase G (PKG) as a plausible intermediate, we wanted to determine the temporal relationship of these two proteins in the induction of apoptosis. We observed a dose-dependent decrease in MDA-MB-468 cell viability, which was co-incident with increased PKG activity as measured by VASPSer239 phosphorylation. In addition, we observed a dose dependent decrease in cell viability, as well as an increase in apoptosis, in response to two different PKG agonists, 8-Bromo-cGMP and 8-pCPT-cGMP. MDA-MB-468 cells with reduced PKG activity had attenuated EGFR-mediated apoptosis. These findings indicate that PKG does not induce cell death via transphosphorylation of the EGFR. Instead, PKG activity occurs following EGFR activation. Together, these data indicate PKG as an intermediary in EGFR-mediated cell death, likely via apoptotic pathway. PMID:27381222

  18. Glycosylation-mediated phenylpropanoid partitioning in Populus tremuloides cell cultures

    Directory of Open Access Journals (Sweden)

    Babst Benjamin A

    2009-12-01

    identified candidate genes for glycosyltransferases that may mediate the glycosylation, and for transporters that mediate the subcellular compartmentalization of sugars and phenolic glycosides. The suspension cells appear to represent a facile system for dissecting the regulation of phenolic carbon partitioning, and in turn, its effects on growth in Populus.

  19. Integrin Receptors on Tumor Cells Facilitate NK cell-mediated Antibody-dependent Cytotoxicity

    OpenAIRE

    Anikeeva, Nadia; Steblyanko, Maria; Fayngerts, Svetlana; Kopylova, Natalya; Marshall, Deborah J.; Powers, Gordon D.; Sato, Takami; Campbell, Kerry S.; Sykulev, Yuri

    2014-01-01

    NK cells that mediate ADCC play an important role in tumor-specific immunity. We have examined factors limiting specific lysis of tumor cells by CD16.NK-92 cells induced by CNTO 95LF antibodies recognizing αV integrins that are overexpressed on many tumor cells. Although all tested tumor cells were killed by CD16.NK-92 effectors in the presence of the antibodies, the killing of target cells with a low level of ICAM-1 expression revealed a dramatic decrease in their specific lysis at high anti...

  20. Selectins mediate small cell lung cancer systemic metastasis.

    Directory of Open Access Journals (Sweden)

    Franziska Heidemann

    Full Text Available Metastasis formation is the major reason for the extremely poor prognosis in small cell lung cancer (SCLC patients. The molecular interaction partners regulating metastasis formation in SCLC are largely unidentified, however, from other tumor entities it is known that tumor cells use the adhesion molecules of the leukocyte adhesion cascade to attach to the endothelium at the site of the future metastasis. Using the human OH-1 SCLC line as a model, we found that these cells expressed E- and P-selectin binding sites, which could be in part attributed to the selectin binding carbohydrate motif sialyl Lewis A. In addition, protein backbones known to carry these glycotopes in other cell lines including PSGL-1, CD44 and CEA could be detected in in vitro and in vivo grown OH1 SCLC cells. By intravital microscopy of murine mesenterial vasculature we could capture SCLC cells while rolling along vessel walls demonstrating that SCLC cells mimic leukocyte rolling behavior in terms of selectin and selectin ligand interaction in vivo indicating that this mechanism might indeed be important for SCLC cells to seed distant metastases. Accordingly, formation of spontaneous distant metastases was reduced by 50% when OH-1 cells were xenografted into E-/P-selectin-deficient mice compared with wild type mice (p = 0.0181. However, as metastasis formation was not completely abrogated in selectin deficient mice, we concluded that this adhesion cascade is redundant and that other molecules of this cascade mediate metastasis formation as well. Using several of these adhesion molecules as interaction partners presumably make SCLC cells so highly metastatic.

  1. Establishment of Stable, Cell-Mediated Immunity that Makes "Susceptible" Mice Resistant to Leishmania major

    Science.gov (United States)

    Bretscher, Peter A.; Wei, Guojian; Menon, Juthika N.; Bielefeldt-Ohmann, Helle

    1992-07-01

    Cell-mediated, but not antibody-mediated, immune responses protect humans against certain pathogens that produce chronic diseases such as leishmaniasis. Effective vaccination against such pathogens must therefore produce an immunological "imprint" so that stable, cell-mediated immunity is induced in all individuals after natural infection. BALB/c mice "innately susceptible" to Leishmania major produce antibodies after substantial infection. In the present study, "susceptible" mice injected with a small number of parasites mounted a cell-mediated response and acquired resistance to a larger, normally pathogenic, challenge. This vaccination strategy may be applicable in diseases in which protection is dependent on cell-mediated immunity.

  2. T Cell-Mediated Modulation of Mast Cell Function: Heterotypic Adhesion-Induced Stimulatory or Inhibitory Effects

    OpenAIRE

    Mekori, Yoseph A.; Hershko, Alon Y.

    2012-01-01

    Close physical proximity between mast cells and T cells has been demonstrated in several T cell mediated inflammatory processes such as rheumatoid arthritis and sarcoidosis. However, the way by which mast cells are activated in these T cell-mediated immune responses has not been fully elucidated. We have identified and characterized a novel mast cell activation pathway initiated by physical contact with activated T cells, and showed that this pathway is associated with degranulation and cytok...

  3. Epigenetically Mediated Pathogenic Effects of Phenanthrene on Regulatory T Cells

    Directory of Open Access Journals (Sweden)

    Jing Liu

    2013-01-01

    Full Text Available Phenanthrene (Phe, a polycyclic aromatic hydrocarbon (PAH, is a major constituent of urban air pollution. There have been conflicting results regarding the role of other AhR ligands 2,3,7,8- tetrachlorodibenzo-p-dioxin (TCDD and 6-formylindolo [3,2-b]carbazole (FICZ in modifying regulatory T cell populations (Treg or T helper (Th17 differentiation, and the effects of Phe have been understudied. We hypothesized that different chemical entities of PAH induce Treg to become either Th2 or Th17 effector T cells through epigenetic modification of FOXP3. To determine specific effects on T cell populations by phenanthrene, primary human Treg were treated with Phe, TCDD, or FICZ and assessed for function, gene expression, and phenotype. Methylation of CpG sites within the FOXP3 locus reduced FOXP3 expression, leading to impaired Treg function and conversion of Treg into a CD4+CD25lo Th2 phenotype in Phe-treated cells. Conversely, TCDD treatment led to epigenetic modification of IL-17A and conversion of Treg to Th17 T cells. These findings present a mechanism by which exposure to AhR-ligands mediates human T cell responses and begins to elucidate the relationship between environmental exposures, immune modulation, and initiation of human disease.

  4. Signals mediating Klotho-induced neuroprotection in hippocampal neuronal cells.

    Science.gov (United States)

    Cheng, Meng-Fu; Chen, Li-Jen; Niu, Ho-Shan; Yang, Ting-Ting; Lin, Kao-Chang; Cheng, Juei-Tang

    2015-01-01

    The erythropoietin (Epo) receptor (EpoR) is expressed in the brain and was shown to have neuroprotective effects against brain damage in animal models. A recent study indicated that EpoR and its activity are the downstream effectors of Klotho for cytoprotection in the kidney. Thus, we propose that Klotho can stimulate the expression of EpoR in neuronal cells to enhance Epo-mediated protection. H19-7 hippocampal neuronal cells were treated with recombinant Klotho. In H19-7 cells, Klotho increased the expression of both the EpoR protein and mRNA. Klotho also enhanced the transcription activity of the EpoR promoter in H19-7 cells. Moreover, Klotho augmented the Epo-triggered phosphorylation of Jak2 and Stat5 and protected H19-7 cells from hydrogen peroxide cytotoxicity. The silencing of EpoR abolished the protective effect of Klotho against peroxide-induced cytotoxicity. Finally, the silencing of GATA1 diminished the Klotho-induced increase in EpoR protein and mRNA expression as well as its promoter activity. In conclusion, Klotho increased EpoR expression in neuronal cells through GATA1, thereby enabling EpoR to function as a cytoprotective protein against oxidative injury. PMID:25856523

  5. Lung Regeneration: Endogenous and Exogenous Stem Cell Mediated Therapeutic Approaches

    Directory of Open Access Journals (Sweden)

    Khondoker M. Akram

    2016-01-01

    Full Text Available The tissue turnover of unperturbed adult lung is remarkably slow. However, after injury or insult, a specialised group of facultative lung progenitors become activated to replenish damaged tissue through a reparative process called regeneration. Disruption in this process results in healing by fibrosis causing aberrant lung remodelling and organ dysfunction. Post-insult failure of regeneration leads to various incurable lung diseases including chronic obstructive pulmonary disease (COPD and idiopathic pulmonary fibrosis. Therefore, identification of true endogenous lung progenitors/stem cells, and their regenerative pathway are crucial for next-generation therapeutic development. Recent studies provide exciting and novel insights into postnatal lung development and post-injury lung regeneration by native lung progenitors. Furthermore, exogenous application of bone marrow stem cells, embryonic stem cells and inducible pluripotent stem cells (iPSC show evidences of their regenerative capacity in the repair of injured and diseased lungs. With the advent of modern tissue engineering techniques, whole lung regeneration in the lab using de-cellularised tissue scaffold and stem cells is now becoming reality. In this review, we will highlight the advancement of our understanding in lung regeneration and development of stem cell mediated therapeutic strategies in combating incurable lung diseases.

  6. Schemas and memory consolidation.

    Science.gov (United States)

    Tse, Dorothy; Langston, Rosamund F; Kakeyama, Masaki; Bethus, Ingrid; Spooner, Patrick A; Wood, Emma R; Witter, Menno P; Morris, Richard G M

    2007-04-01

    Memory encoding occurs rapidly, but the consolidation of memory in the neocortex has long been held to be a more gradual process. We now report, however, that systems consolidation can occur extremely quickly if an associative "schema" into which new information is incorporated has previously been created. In experiments using a hippocampal-dependent paired-associate task for rats, the memory of flavor-place associations became persistent over time as a putative neocortical schema gradually developed. New traces, trained for only one trial, then became assimilated and rapidly hippocampal-independent. Schemas also played a causal role in the creation of lasting associative memory representations during one-trial learning. The concept of neocortical schemas may unite psychological accounts of knowledge structures with neurobiological theories of systems memory consolidation.

  7. β-Cell Regeneration Mediated by Human Bone Marrow Mesenchymal Stem Cells

    OpenAIRE

    Anna Milanesi; Jang-Won Lee; Zhenhua Li; Stefano Da Sacco; Valentina Villani; Vanessa Cervantes; Laura Perin; Yu, John S.

    2012-01-01

    Bone marrow mesenchymal stem cells (BMSCs) have been shown to ameliorate diabetes in animal models. The mechanism, however, remains largely unknown. An unanswered question is whether BMSCs are able to differentiate into β-cells in vivo, or whether BMSCs are able to mediate recovery and/or regeneration of endogenous β-cells. Here we examined these questions by testing the ability of hBMSCs genetically modified to transiently express vascular endothelial growth factor (VEGF) or pancreatic-duode...

  8. Patterns of Failure in Advanced Stage Diffuse Large B-Cell Lymphoma Patients After Complete Response to R-CHOP Immunochemotherapy and the Emerging Role of Consolidative Radiation Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Shi, Zheng [Department of Radiation Oncology, Emory University, Atlanta, Georgia (United States); Winship Cancer Institute, Emory University, Atlanta, Georgia (United States); Das, Satya; Okwan-Duodu, Derick [Emory University School of Medicine, Atlanta, Georgia (United States); Esiashvili, Natia [Department of Radiation Oncology, Emory University, Atlanta, Georgia (United States); Winship Cancer Institute, Emory University, Atlanta, Georgia (United States); Flowers, Christopher [Winship Cancer Institute, Emory University, Atlanta, Georgia (United States); Department of Medical Oncology, Emory University, Atlanta, Georgia (United States); Chen, Zhengjia; Wang, Xiaojing [Winship Cancer Institute, Emory University, Atlanta, Georgia (United States); Department of Biostatistics and Bioinformatics, Emory University, Atlanta, Georgia (United States); Jiang, Kun [Department of Pathology, Emory University, Atlanta, Georgia (United States); Nastoupil, Loretta J. [Winship Cancer Institute, Emory University, Atlanta, Georgia (United States); Department of Medical Oncology, Emory University, Atlanta, Georgia (United States); Khan, Mohammad K., E-mail: drkhurram2000@gmail.com [Department of Radiation Oncology, Emory University, Atlanta, Georgia (United States); Winship Cancer Institute, Emory University, Atlanta, Georgia (United States)

    2013-07-01

    Purpose: The role of consolidative radiation therapy (RT) after complete response (CR) to rituximab combined with cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) for stage III-IV diffuse large B-cell lymphoma (DLBCL) patients is unclear. We aimed to evaluate our institutional experience when consolidative RT is delivered to initial presenting sites or bulky sites in these patients. Methods and Materials: We identified 211 histologically confirmed stage III-IV DLBCL patients who received R-CHOP from January 2000 to May 2012 at our institution. Patterns of failure for patients who achieved CR to R-CHOP were analyzed. Local control (LC), distant control (DC), progression-free survival (PFS), and overall survival (OS) were estimated using Kaplan-Meier method and compared between patients who received R-CHOP alone versus R-CHOP plus consolidative RT using the log–rank test. Multivariate analyses were also performed using Cox proportional hazards model. Results: Detailed treatment records were available for 163 patients. After a median 6 cycles of R-CHOP, 110 patients (67.5%) achieved CR and were entered for analysis. Fourteen patients (12.7%) received consolidative RT. After median follow-up of 32.9 months, 43.8% of patients who received R-CHOP alone failed at the initial sites with or without distant recurrence (DR), whereas isolated DR only occurred in 3.7% of these patients. Consolidative RT was associated with significantly improved LC (91.7% vs 48.8%), DC (92.9% vs 71.9%), PFS (85.1% vs 44.2%), and OS (92.3% vs 68.5%; all Ps<.0001) at 5 years compared with patients with R-CHOP alone. On multivariate analysis, consolidative RT and nonbulky disease were predictive of increased LC and PFS, whereas bone marrow involvement was associated with increased risk of DR and worse OS. Consolidative RT was also associated with marginal improved OS. Conclusions: Forty-four percent of patients with advanced stage DLBCL failed at initial presenting sites after

  9. NKG2D ligands mediate immunosurveillance of senescent cells.

    Science.gov (United States)

    Sagiv, Adi; Burton, Dominick G A; Moshayev, Zhana; Vadai, Ezra; Wensveen, Felix; Ben-Dor, Shifra; Golani, Ofra; Polic, Bojan; Krizhanovsky, Valery

    2016-02-01

    Cellular senescence is a stress response mechanism that limits tumorigenesis and tissue damage. Induction of cellular senescence commonly coincides with an immunogenic phenotype that promotes self-elimination by components of the immune system, thereby facilitating tumor suppression and limiting excess fibrosis during wound repair. The mechanisms by which senescent cells regulate their immune surveillance are not completely understood. Here we show that ligands of an activating Natural Killer (NK) cell receptor (NKG2D), MICA and ULBP2 are consistently up-regulated following induction of replicative senescence, oncogene-induced senescence and DNA damage - induced senescence. MICA and ULBP2 proteins are necessary for efficient NK-mediated cytotoxicity towards senescent fibroblasts. The mechanisms regulating the initial expression of NKG2D ligands in senescent cells are dependent on a DNA damage response, whilst continuous expression of these ligands is regulated by the ERK signaling pathway. In liver fibrosis, the accumulation of senescent activated stellate cells is increased in mice lacking NKG2D receptor leading to increased fibrosis. Overall, our results provide new insights into the mechanisms regulating the expression of immune ligands in senescent cells and reveal the importance of NKG2D receptor-ligand interaction in protecting against liver fibrosis. PMID:26878797

  10. Interstitial cells of Cajal mediate mechanosensitive responses in the stomach

    Science.gov (United States)

    Won, Kyung-Jong; Sanders, Kenton M.; Ward, Sean M.

    2005-10-01

    Changes in motor activity are a basic response to filling of smooth muscle organs. Responses to gastric filling, for example, are thought to be regulated by neural reflexes. Here, we demonstrate a previously uncharacterized aspect of stretch-dependent responses in visceral smooth muscles that is mediated by mechanosensitive interstitial cells of Cajal. Length ramps were applied to the murine antral muscles while recording intracellular electrical activity and isometric force. Stretching muscles by an average of 27 ± 1% of resting length resulted in 5 mN of force. Increasing length caused membrane depolarization and increased slow-wave frequency. The responses were dependent on the rate of stretch. Stretch-dependent responses were not inhibited by neuronal antagonists or nifedipine. Increases in slow-wave frequency, but not membrane depolarization, were inhibited by reducing external Ca2+ (100 μM) and by Ni2+ (250 μM). Responses to stretch were inhibited by indomethacin (1 μM) and were absent in cyclooxygenase II-deficient mice, suggesting that cyclooxygenase II-derived eicosanoids may mediate these responses. Dual microelectrode impalements of muscle cells within the corpus and antrum showed that stretch-induced changes in slow-wave frequency uncoupled proximal-to-distal propagation of slow waves. This uncoupling could interfere with gastric peristalsis and impede gastric emptying. Stretch of antral muscles of W/WV mice, which lack intramuscular interstitial cells of Cajal, did not affect membrane depolarization or slow-wave frequency. These data demonstrate a previously uncharacterized nonneural stretch reflex in gastric muscles and provide physiological evidence demonstrating a mechanosensitive role for interstitial cells of Cajal in smooth muscle tissues. gastric compliance | pacemaker | stretch | slow waves | propagation

  11. Hepatic non-parenchymal cells and extracellular matrix participate in oval cell-mediated liver regeneration

    Institute of Scientific and Technical Information of China (English)

    Wei Zhang; Xiao-Ping Chen; Wan-Guang Zhang; Feng Zhang; Shuai Xiang; Han-Hua Dong; Lei Zhang

    2009-01-01

    AIM: To elucidate the interaction between nonparenchymal cells, extracellular matrix and oval cells during the restituting process of liver injury induced by partial hepatectomy (PH). METHODS: We examined the localization of oval cells, non-parenchymal cells, and the extracellular matrix components using immunohistochemical and double immunofluorescent analysis during the proliferation and differentiation of oval cells in N-2-acetylaminofluorene (2-AAF)/PH rat model. RESULTS: By day 2 after PH, small oval cells began to proliferate around the portal area. Most of stellate cells and laminin were present along the hepatic sinusoids in the periportal area. Kupffer cells and fibronectin markedly increased in the whole hepatic lobule. From day 4 to 9, oval cells spread further into hepatic parenchyma, closely associated with stellate cells, fibronectin and laminin. Kupffer cells admixed with oval cells by day 6 and then decreased in the periportal zone. From day 12 to 15, most of hepatic stellate cells (HSCs), laminin and fibronectin located around the small hepatocyte nodus, and minority of them appeared in the nodus. Kupffer cells were mainly limited in the pericentral sinusoids. After day 18, the normal liver lobule structures began to recover.CONCLUSION: Local hepatic microenvironment may participate in the oval cell-mediated liver regeneration through the cell-cell and cell-matrix interactions.

  12. Amphiregulin mediates self-renewal in an immortal mammary epithelial cell line with stem cell characteristics

    Energy Technology Data Exchange (ETDEWEB)

    Booth, Brian W., E-mail: brbooth@clemson.edu [Mammary Biology and Tumorigenesis Laboratory, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892 (United States); Institute for Biological Interfaces of Engineering, Clemson University, Clemson, SC 29634 (United States); Boulanger, Corinne A.; Anderson, Lisa H. [Mammary Biology and Tumorigenesis Laboratory, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892 (United States); Jimenez-Rojo, Lucia; Brisken, Cathrin [Ecole polytechnique federale de Lausanne (EPFL), ISREC-Swiss Institute for Experimental Research, NCCR Molecular Oncology, SV.832 Station 19 CH-1015, Lausanne (Switzerland); Smith, Gilbert H., E-mail: gs4d@nih.gov [Mammary Biology and Tumorigenesis Laboratory, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892 (United States)

    2010-02-01

    Amphiregulin (AREG), a ligand for epidermal growth factor receptor, is required for mammary gland ductal morphogenesis and mediates estrogen actions in vivo, emerging as an essential growth factor during mammary gland growth and differentiation. The COMMA-D {beta}-geo (CD{beta}geo) mouse mammary cell line displays characteristics of normal mammary progenitor cells including the ability to regenerate a mammary gland when transplanted into the cleared fat pad of a juvenile mouse, nuclear label retention, and the capacity to form anchorage-independent mammospheres. We demonstrate that AREG is essential for formation of floating mammospheres by CD{beta}geo cells and that the mitogen activated protein kinase signaling pathway is involved in AREG-mediated mammosphere formation. Addition of exogenous AREG promotes mammosphere formation in cells where AREG expression is knocked down by siRNA and mammosphere formation by AREG{sup -/-} mammary epithelial cells. AREG knockdown inhibits mammosphere formation by duct-limited mammary progenitor cells but not lobule-limited mammary progenitor cells. These data demonstrate AREG mediates the function of a subset of mammary progenitor cells in vitro.

  13. Consolidating BPR with CALS

    DEFF Research Database (Denmark)

    Larsen, Michael Holm; Leinsdorff, Torben; Madsen, Claus;

    1999-01-01

    the efficiency of the concept. However, limited directions are provided.This article suggests that Continuous Acquisition and Lifecycle Support (CALS) is a viable concept to complement and thus consolidate BPR. This is based on two hypotheses stating that CALS provides guidelines for applying IT to increase...

  14. Abstraction and Consolidation

    Science.gov (United States)

    Monaghan, John; Ozmantar, Mehmet Fatih

    2006-01-01

    The framework for this paper is a recently developed theory of abstraction in context. The paper reports on data collected from one student working on tasks concerned with absolute value functions. It examines the relationship between mathematical constructions and abstractions. It argues that an abstraction is a consolidated construction that can…

  15. β-Cell regeneration mediated by human bone marrow mesenchymal stem cells.

    Directory of Open Access Journals (Sweden)

    Anna Milanesi

    Full Text Available Bone marrow mesenchymal stem cells (BMSCs have been shown to ameliorate diabetes in animal models. The mechanism, however, remains largely unknown. An unanswered question is whether BMSCs are able to differentiate into β-cells in vivo, or whether BMSCs are able to mediate recovery and/or regeneration of endogenous β-cells. Here we examined these questions by testing the ability of hBMSCs genetically modified to transiently express vascular endothelial growth factor (VEGF or pancreatic-duodenal homeobox 1 (PDX1 to reverse diabetes and whether these cells were differentiated into β-cells or mediated recovery through alternative mechanisms. Human BMSCs expressing VEGF and PDX1 reversed hyperglycemia in more than half of the diabetic mice and induced overall improved survival and weight maintenance in all mice. Recovery was sustained only in the mice treated with hBMSCs-VEGF. However, de novo β-cell differentiation from human cells was observed in mice in both cases, treated with either hBMSCs-VEGF or hBMSCs- PDX1, confirmed by detectable level of serum human insulin. Sustained reversion of diabetes mediated by hBMSCs-VEGF was secondary to endogenous β-cell regeneration and correlated with activation of the insulin/IGF receptor signaling pathway involved in maintaining β-cell mass and function. Our study demonstrated the possible benefit of hBMSCs for the treatment of insulin-dependent diabetes and gives new insight into the mechanism of β-cell recovery after injury mediated by hBMSC therapy.

  16. 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

  17. p-Cresol mediates autophagic cell death in renal proximal tubular cells.

    Science.gov (United States)

    Lin, Hsin-Hung; Huang, Chiu-Ching; Lin, Tze-Yi; Lin, Ching-Yuang

    2015-04-01

    Higher serum level of p-cresol (PC) in chronic kidney disease (CKD) patients has been linked with CKD progression. The toxic effect of PC on diverse cells has been reported by prior studies, except for renal tubular cells. Both autophagy and apoptosis contribute to renal tubular cell death, yet evidence of its response to PC is limited and their crosstalk is still unclear. Autophagy is an important cellular process involved in toxin-induced cell death. Renal tubular cell death in tubular injury is thought to be one of the key events causing the progression of CKD. Thus, we treated rat (NRK-52E) and human (HRPTEC) renal proximal tubular cells (RPTC) with PC and found the cell proliferation was significantly decreased. Cell apoptosis was significantly increased and accompanied with the activation of autophagy as evidenced by increases in LC3-II, beclin 1 and Atg 4. We also found an increase of p62 by c-Jun activation. p62 accumulation could mediate the activation of caspase 8-dependent cell apoptosis. Conversely, knockdown of p62 by siRNA of p62 had the opposite effect by arresting LC3-II accumulation and promoting increasing cell viability. We conclude that PC triggered autophagic RPTC death via JNK-mediated p62 accumulation and then activated caspase 8-dependent cell death pathway. PC can be considered as one of the key events causing progression of CKD, which might affect drug disposition in CKD cases. PMID:25668154

  18. BNNT-mediated irreversible electroporatio: its potential on cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Vittoria Raffa, Cristina Riggio, Michael W. Smith, Kevin C. Jordan, Wei Cao, Alfred Cuschieri

    2012-10-01

    Tissue ablation, i.e., the destruction of undesirable tissues, has become an important minimally invasive technique alternative to resection surgery for the treatment of tumours. Several methods for tissue ablation are based on thermal techniques using cold, e.g. cryosurgery [1] or heat, e.g. radiofrequency [2] or high-intensity focused ultrasound [3] or nanoparticle-mediated irradiation [4]. Alternatively, irreversible electroporation (IRE) has been proposed as non thermal technique for minimally invasive tissue ablation based on the use of electrical pulses. When the electric field is applied to a cell, a change in transmembrane potential is induced, which can cause biochemical and physiological changes of the cell. When the threshold value of the transmembrane potential is exceeded, the cell membrane becomes permeable, thus allowing entrance of molecules that otherwise cannot cross the membrane [5]. A further increase in the electric field intensity may cause irreversible membrane permeabilization and cell death. These pulses create irreversible defects (pores) in the cell membrane lipid bilayer, causing cell death through loss of cell homeostasis [6]. This is desirable in tumour ablation in order to produce large cell death, without the use of cytostatic drugs. A study of Davalos, Mir and Rubinsky showed that IRE can ablate substantial volumes of tissue without inducing a thermal effect and therefore serve as an independent and new tissue ablation modality; this opened the way to the use of IRE in surgery [7]. Their finding was subsequently confirmed in studies on cells [8], small animal models [9] and in large animal models in the liver [10] and the heart [11]. The most important finding in these papers is that irreversible electroporation produces precisely delineated ablation zones with cell scale resolution between ablated and non-ablated areas, without zones in which the extent of damage changes gradually as during thermal ablation. Furthermore, it is

  19. Mast cell mediator tryptase levels after inhalation or intravenous administration of high doses pharmaceutically prepared heroin

    NARCIS (Netherlands)

    E.J. Rook; A.P. van Zanten; W. van den Brink; J.M. van Ree; J.H. Beijnen

    2006-01-01

    Background: Opioids like morphine and heroin induce mast cell degranulation in vitro. The release of mast cell mediators like histamine and tryptase may lead to allergic symptoms. In this study it was investigated whether mast cell mediator release also occurs in vivo in addicted patients who partic

  20. Molecular basis of sidekick-mediated cell-cell adhesion and specificity

    Energy Technology Data Exchange (ETDEWEB)

    Goodman, Kerry M.; Yamagata, Masahito; Jin, Xiangshu; Mannepalli, Seetha; Katsamba, Phinikoula S.; Ahlsén, Göran; Sergeeva, Alina P.; Honig, Barry; Sanes, Joshua R.; Shapiro, Lawrence

    2016-09-19

    Sidekick (Sdk) 1 and 2 are related immunoglobulin superfamily cell adhesion proteins required for appropriate synaptic connections between specific subtypes of retinal neurons. Sdks mediate cell-cell adhesion with homophilic specificity that underlies their neuronal targeting function. Here we report crystal structures of Sdk1 and Sdk2 ectodomain regions, revealing similar homodimers mediated by the four N-terminal immunoglobulin domains (Ig1–4), arranged in a horseshoe conformation. These Ig1–4 horseshoes interact in a novel back-to-back orientation in both homodimers through Ig1:Ig2, Ig1:Ig1 and Ig3:Ig4 interactions. Structure-guided mutagenesis results show that this canonical dimer is required for both Sdk-mediated cell aggregation (viatransinteractions) and Sdk clustering in isolated cells (viacisinteractions). Sdk1/Sdk2 recognition specificity is encoded across Ig1–4, with Ig1–2 conferring the majority of binding affinity and differential specificity. We suggest that competition betweencisandtransinteractions provides a novel mechanism to sharpen the specificity of cell-cell interactions.

  1. M1 muscarinic receptor activation mediates cell death in M1-HEK293 cells.

    Science.gov (United States)

    Graham, E Scott; Woo, Kerhan K; Aalderink, Miranda; Fry, Sandie; Greenwood, Jeffrey M; Glass, Michelle; Dragunow, Mike

    2013-01-01

    HEK293 cells have been used extensively to generate stable cell lines to study G protein-coupled receptors, such as muscarinic acetylcholine receptors (mAChRs). The activation of M1 mAChRs in various cell types in vitro has been shown to be protective. To further investigate M1 mAChR-mediated cell survival, we generated stable HEK293 cell-lines expressing the human M1 mAChR. M1 mAChRs were efficiently expressed at the cell surface and efficiently internalised within 1 h by carbachol. Carbachol also induced early signalling cascades similar to previous reports. Thus, ectopically expressed M1 receptors behaved in a similar fashion to the native receptor over short time periods of analysis. However, substantial cell death was observed in HEK293-M1 cells within 24 h after carbachol application. Death was only observed in HEK cells expressing M1 receptors and fully blocked by M1 antagonists. M1 mAChR-stimulation mediated prolonged activation of the MEK-ERK pathway and resulted in prolonged induction of the transcription factor EGR-1 (>24 h). Blockade of ERK signalling with U0126 did not reduce M1 mAChR-mediated cell-death significantly but inhibited the acute induction of EGR-1. We investigated the time-course of cell death using time-lapse microscopy and xCELLigence technology. Both revealed the M1 mAChR cytotoxicity occurs within several hours of M1 activation. The xCELLigence assay also confirmed that the ERK pathway was not involved in cell-death. Interestingly, the MEK blocker did reduce carbachol-mediated cleaved caspase 3 expression in HEK293-M1 cells. The HEK293 cell line is a widely used pharmacological tool for studying G-protein coupled receptors, including mAChRs. Our results highlight the importance of investigating the longer term fate of these cells in short term signalling studies. Identifying how and why activation of the M1 mAChR signals apoptosis in these cells may lead to a better understanding of how mAChRs regulate cell-fate decisions.

  2. Distinct gut-derived lactic acid bacteria elicit divergent dendritic cell-mediated NK cell responses

    DEFF Research Database (Denmark)

    Fink, Lisbeth Nielsen; Zeuthen, Louise Hjerrild; Christensen, Hanne;

    2007-01-01

    Lactic acid bacteria (LAB) are abundant in the gastrointestinal tract where they continuously regulate the immune system. NK cells are potently activated by dendritic cells (DCs) matured by inflammatory stimuli, and NK cells are present in the gut epithelium and in mesenteric lymph nodes...... in their ability to induce DC-dependent IFN-gamma production by NK cells. This suggests that DCs stimulated by gut LAB may expand the pool of NK cells and increase their cytotoxic potential. Specific LAB, inducing high levels of IL-12 in DCs, may promote amplification of a type-1 response via potent stimulation...... of IFN-gamma production in NK cells. Combining IFN-gamma-inducing and non-inducing LAB completely abrogates DC-mediated IFN-gamma production by NK cells, and therefore LAB modulating IFN-gamma production in NK cells may be important regulators of the immune response....

  3. Regulation of VH replacement by B cell receptor-mediated signaling in human immature B cells.

    Science.gov (United States)

    Liu, Jing; Lange, Miles D; Hong, Sang Yong; Xie, Wanqin; Xu, Kerui; Huang, Lin; Yu, Yangsheng; Ehrhardt, Götz R A; Zemlin, Michael; Burrows, Peter D; Su, Kaihong; Carter, Robert H; Zhang, Zhixin

    2013-06-01

    VH replacement provides a unique RAG-mediated recombination mechanism to edit nonfunctional IgH genes or IgH genes encoding self-reactive BCRs and contributes to the diversification of Ab repertoire in the mouse and human. Currently, it is not clear how VH replacement is regulated during early B lineage cell development. In this article, we show that cross-linking BCRs induces VH replacement in human EU12 μHC(+) cells and in the newly emigrated immature B cells purified from peripheral blood of healthy donors or tonsillar samples. BCR signaling-induced VH replacement is dependent on the activation of Syk and Src kinases but is inhibited by CD19 costimulation, presumably through activation of the PI3K pathway. These results show that VH replacement is regulated by BCR-mediated signaling in human immature B cells, which can be modulated by physiological and pharmacological treatments.

  4. Plant Cell Division Analyzed by Transient Agrobacterium-Mediated Transformation of Tobacco BY-2 Cells.

    Science.gov (United States)

    Buschmann, Henrik

    2016-01-01

    The continuing analysis of plant cell division will require additional protein localization studies. This is greatly aided by GFP-technology, but plant transformation and the maintenance of transgenic lines can present a significant technical bottleneck. In this chapter I describe a method for the Agrobacterium-mediated genetic transformation of tobacco BY-2 cells. The method allows for the microscopic analysis of fluorescence-tagged proteins in dividing cells in within 2 days after starting a coculture. This transient transformation procedure requires only standard laboratory equipment. It is hoped that this rapid method would aid researchers conducting live-cell localization studies in plant mitosis and cytokinesis.

  5. Autophagy as a Survival Mechanism for Squamous Cell Carcinoma Cells in Endonuclease G-Mediated Apoptosis

    Science.gov (United States)

    Masui, Atsushi; Hamada, Masakazu; Kameyama, Hiroyasu; Wakabayashi, Ken; Takasu, Ayako; Imai, Tomoaki; Iwai, Soichi; Yura, Yoshiaki

    2016-01-01

    Safingol, L- threo-dihydrosphingosine, induces cell death in human oral squamous cell carcinoma (SCC) cells through an endonuclease G (endoG) -mediated pathway. We herein determined whether safingol induced apoptosis and autophagy in oral SCC cells. Safingol induced apoptotic cell death in oral SCC cells in a dose-dependent manner. In safingol-treated cells, microtubule-associated protein 1 light chain 3 (LC3)-I was changed to LC3-II and the cytoplasmic expression of LC3, amount of acidic vesicular organelles (AVOs) stained by acridine orange and autophagic vacuoles were increased, indicating the occurrence of autophagy. An inhibitor of autophagy, 3-methyladenine (3-MA), enhanced the suppressive effects of safingol on cell viability, and this was accompanied by an increase in the number of apoptotic cells and extent of nuclear fragmentation. The nuclear translocation of endoG was minimal at a low concentration of safingol, but markedly increased when combined with 3-MA. The suppressive effects of safingol and 3-MA on cell viability were reduced in endoG siRNA- transfected cells. The scavenging of reactive oxygen species (ROS) prevented cell death induced by the combinational treatment, whereas a pretreatment with a pan-caspase inhibitor z-VAD-fmk did not. These results indicated that safingol induced apoptosis and autophagy in SCC cells and that the suppression of autophagy by 3-MA enhanced apoptosis. Autophagy supports cell survival, but not cell death in the SCC cell system in which apoptosis occurs in an endoG-mediated manner. PMID:27658240

  6. Endocannabinoid Signaling within the Basolateral Amygdala Integrates Multiple Stress Hormone Effects on Memory Consolidation

    Science.gov (United States)

    Atsak, Piray; Hauer, Daniela; Campolongo, Patrizia; Schelling, Gustav; Fornari, Raquel V; Roozendaal, Benno

    2015-01-01

    Glucocorticoid hormones are known to act synergistically with other stress-activated neuromodulatory systems, such as norepinephrine and corticotropin-releasing factor (CRF), within the basolateral complex of the amygdala (BLA) to induce optimal strengthening of the consolidation of long-term memory of emotionally arousing experiences. However, as the onset of these glucocorticoid actions appear often too rapid to be explained by genomic regulation, the neurobiological mechanism of how glucocorticoids could modify the memory-enhancing properties of norepinephrine and CRF remained elusive. Here, we show that the endocannabinoid system, a rapidly activated retrograde messenger system, is a primary route mediating the actions of glucocorticoids, via a glucocorticoid receptor on the cell surface, on BLA neural plasticity and memory consolidation. Furthermore, glucocorticoids recruit downstream endocannabinoid activity within the BLA to interact with both the norepinephrine and CRF systems in enhancing memory consolidation. These findings have important implications for understanding the fine-tuned crosstalk between multiple stress hormone systems in the coordination of (mal)adaptive stress and emotional arousal effects on neural plasticity and memory consolidation. PMID:25547713

  7. Nonlinear Finite Strain Consolidation Analysis with Secondary Consolidation Behavior

    Directory of Open Access Journals (Sweden)

    Jieqing Huang

    2014-01-01

    Full Text Available This paper aims to analyze nonlinear finite strain consolidation with secondary consolidation behavior. On the basis of some assumptions about the secondary consolidation behavior, the continuity equation of pore water in Gibson’s consolidation theory is modified. Taking the nonlinear compressibility and nonlinear permeability of soils into consideration, the governing equation for finite strain consolidation analysis is derived. Based on the experimental data of Hangzhou soft clay samples, the new governing equation is solved with the finite element method. Afterwards, the calculation results of this new method and other two methods are compared. It can be found that Gibson’s method may underestimate the excess pore water pressure during primary consolidation. The new method which takes the secondary consolidation behavior, the nonlinear compressibility, and nonlinear permeability of soils into consideration can precisely estimate the settlement rate and the final settlement of Hangzhou soft clay sample.

  8. Cell mediated immune response in human antirabies revaccination

    Directory of Open Access Journals (Sweden)

    Débora Regina Veiga

    1987-04-01

    Full Text Available The occurrence of secondary cell mediated immune response (CMI in human antirabies immunization was studied. The Puenzalida & Palácios vaccine was used because it is routinely used in Brazil. CMI was evaluated by lymphoblastic transformation indices obtained in whole blood culture in the presence of rabies and control (nervous tissue antigens. Eleven volunteers submitted to revaccination constituted the group under study, while three other volunteers submitted primo vaccination were utilized as control group. A clear secondary CMI to rabies antigen was detected in all the revaccinated volunteers who showed earlier and more intense response than the control group. Response to the control antigen, however, present in all the components of the first group was not detectable in two out of the three primovaccinated and very low in the third one.

  9. Concurrent cisplatin, continuous infusion fluorouracil and radiotherapy followed by tailored consolidation treatment in non metastatic anal squamous cell carcinoma

    Directory of Open Access Journals (Sweden)

    Petralia Giuseppe

    2011-02-01

    Full Text Available Abstract Background To evaluate efficacy and feasibility of chemo-radiotherapy in patients with non-metastatic anal squamous-cell-cancer. Methods TNM staged anal squamous-cell cancer patients were treated with pelvic radiotherapy concomitant to continuous infusion fluorouracil plus cisplatin for at least 2 cycles. In T3-T4 or any T - N+ tumours or in "slow-responder" cases, 1-2 chemotherapy courses were subsequently administered. Tumour assessment was performed at baseline and 6-8 weeks after radiotherapy to evaluate response. Results 29 patients were enrolled: 4 males, 25 females; median age 57 years; baseline T1/T2/T3/T4 2/12/7/8; N involvement 17. Median dose pelvic radiotherapy was 59.4 Gy (range: 54-74. In 5 patients 2 chemotherapy courses, in 12 patients three and in 12 patients four courses were performed. At first evaluation, 27 CR (93.1%; 95% CI: 78% - 98% and 2 SD were observed. Main grade (G 3 toxic events were neutropenia (8%, diarrhoea (8% and dermatitis (62%. Most frequent late events G3-G4 occurred in 14 patients: proctitis (5, dermatitis (4, bladder dysfunctions (2, sexual dysfunctions (9, lower extremity venous thromboses (2, dysuria (1, stenosis (1 and tenesmus (1. Five patients reported G1 leucopoenia. The rate of colostomy was 14%. After a median follow up of 42 months (range: 4-81, 20 patients are still alive without relapse and 3 died due to PD. The estimated 7-year DFS was 83.4% (C.I.: 68.3%-98.5% and the estimated 7-year OS was 85.7% (C.I.: 70% - 100%. The 1-year and the estimated 7-year colostomy-free survivals were 85.9% (C.I.: 73.1% - 98.7%. Conclusions Concurrent cisplatin plus fluorouracil and radiotherapy is associated with favourable local control rates and acute toxicity. Future investigations will be directed towards research into molecular biomarkers related to disease progression and resistance to chemo-radiotherapy and to the evaluation of new cytotoxic agents or targeted drugs, such as anti-epidermal growth

  10. Integrin receptors on tumor cells facilitate NK cell-mediated antibody-dependent cytotoxicity.

    Science.gov (United States)

    Anikeeva, Nadia; Steblyanko, Maria; Fayngerts, Svetlana; Kopylova, Natalya; Marshall, Deborah J; Powers, Gordon D; Sato, Takami; Campbell, Kerry S; Sykulev, Yuri

    2014-08-01

    NK cells that mediate ADCC play an important role in tumor-specific immunity. We have examined factors limiting specific lysis of tumor cells by CD16.NK-92 cells induced by CNTO 95LF antibodies recognizing αV integrins that are overexpressed on many tumor cells. Although all tested tumor cells were killed by CD16.NK-92 effectors in the presence of the antibodies, the killing of target cells with a low level of ICAM-1 expression revealed a dramatic decrease in their specific lysis at high antibody concentration, revealing a dose limiting effect. A similar effect was also observed with primary human NK cells. The effect was erased after IFN-γ treatment of tumor cells resulting in upregulation of ICAM-1. Furthermore, killing of the same tumor cells induced by Herceptin antibody was significantly impaired in the presence of CNTO 95Ala-Ala antibody variant that blocks αV integrins but is incapable of binding to CD16. These data suggest that αV integrins on tumor cells could compensate for the loss of ICAM-1 molecules, thereby facilitating ADCC by NK cells. Thus, NK cells could exercise cytolytic activity against ICAM-1 deficient tumor cells in the absence of proinflammatory cytokines, emphasizing the importance of NK cells in tumor-specific immunity at early stages of cancer. PMID:24810893

  11. MACROTHEORETICAL FOUNDATIONS OF FISCAL CONSOLIDATION

    Directory of Open Access Journals (Sweden)

    I. Liutyi

    2016-06-01

    Full Text Available The article analyses the unexplored category of "fiscal consolidation". The study shows a different interpretation of the content of fiscal consolidation. It was emphasized that in today's fiscal policy in the EU aims mainly at implementing fiscal consolidation programs that provide sustainable public finances by implementing measures to limit the fiscal imbalances (especially deficit of governance and public debt. The paper analyses the fiscal consolidation program aimed at stabilizing of public finances and improve their sustainability. The research proved that fiscal rules and norms contribute to the process of fiscal consolidation.

  12. Fiscal consolidation strategy

    OpenAIRE

    Cogan, John F.; John B. Taylor; Wieland, Volker; Wolters, Maik H

    2012-01-01

    In the aftermath of the global financial crisis and great recession, many countries face substantial deficits and growing debts. In the United States, federal government outlays as a ratio to GDP rose substantially from about 19.5 percent before the crisis to over 24 percent after the crisis. In this paper we consider a fiscal consolidation strategy that brings the budget to balance by gradually reducing this spending ratio over time to the level that prevailed prior to the crisis. A crucial ...

  13. Ezrin dephosphorylation/downregulation contributes to ursolic acid-mediated cell death in human leukemia cells

    International Nuclear Information System (INIS)

    Ezrin links the actin filaments with the cell membrane and has a functional role in the apoptotic process. It appears clear that ezrin is directly associated with Fas, leading to activation of caspase cascade and cell death. However, the exact role of ezrin in ursolic acid (UA)-induced apoptosis remains unclear. In this study, we show for the first time that UA induces apoptosis in both transformed and primary leukemia cells through dephosphorylation/downregulation of ezrin, association and polarized colocalization of Fas and ezrin, as well as formation of death-inducing signaling complex. These events are dependent on Rho-ROCK1 signaling pathway. Knockdown of ezrin enhanced cell death mediated by UA, whereas overexpression of ezrin attenuated UA-induced apoptosis. Our in vivo study also showed that UA-mediated inhibition of tumor growth of mouse leukemia xenograft model is in association with the dephosphorylation/downregulation of ezrin. Such findings suggest that the cytoskeletal protein ezrin may represent an attractive target for UA-mediated lethality in human leukemia cells

  14. Langerhans Cells Suppress CD49a+ NK Cell-Mediated Skin Inflammation.

    Science.gov (United States)

    Scholz, Felix; Naik, Shruti; Sutterwala, Fayyaz S; Kaplan, Daniel H

    2015-09-01

    Recruitment of innate immune effector cells into sites of infection is a critical component of resistance to pathogen infection. Using a model of intradermal footpad injection of Candida albicans, we observed that inflammation as measured by footpad thickness and neutrophil recruitment occurred independent of adoptive immunity but was significantly reduced in MyD88(-/-) and IL-6(-/-) mice. Unexpectedly, huLangerin-DTA mice (ΔLC) that lack Langerhans cells (LC) developed increased skin inflammation and expressed higher amounts of IL-6, suggesting a suppressive role for LC. Increased inflammation also occurred in Rag1(-/-) ΔLC mice but was reversed by Ab-mediated ablation of NK cells. CXCR6(+)CD49a(+) NK cells are a liver-resident subset that can mediate inflammatory skin responses. We found that exaggerated skin inflammation was absent in ΔLC × CXCR6(-/-) mice. Moreover, the exaggerated response in ΔLC mice could be adoptively transferred with liver CD49a(+) NK cells. Finally, CD49a(+) NK cells in ΔLC but not control mice were recruited to the skin, and inhibition of their recruitment prevented the exaggerated response. Thus, in the absence of LC, CD49a(+) liver NK cells display an inappropriately proinflammatory phenotype that results in increased local skin inflammation. These data reveal a novel function for LC in the regulation of this recently described subset of skin tropic NK cells. PMID:26209621

  15. Palliative chemotherapy followed by consolidation radiotherapy in patients with advanced and metastatic non-small cell lung cancer not suitable for radical treatment

    Institute of Scientific and Technical Information of China (English)

    Hany Eldeeb; Philip Gamileri; Ghoi Mak

    2012-01-01

    Objective: This is a retrospective study to assess the effectiveness of consolidation radiotherapy (CRT) following palliative chemotherapy in patients with metastatic or locally advanced non-small cell lung cancer (NSCLC) who are not suitable for radical treatment. Methods: This study involved retrospective analysis of a prospective database of Northampton Oncology Centre from January 2005 to December 2010,63 patients with advanced/metastatic NSCLC treated at the oncology centre were enrolled. Patients were either treated with high dose (39/36 Gy /13-12 fractions, group 1) or low dose (20 Gy / 5 fractions, group 2) CRT or those were not offered any CRT (group 3). Results: There was no significant difference between the three groups as regard age, sex, performance status, comorbidities or chemotherapy given. However there was a statistically significant difference as regard the stage P = 0.009 with more stage IV patients at group Ⅱ and Ⅲ compared to group l. The mean survival for the three groups was 27 months, 14 months &15 months, respectively. There was a statistically significant improvement of survival in patients treated with high dose palliative CRT compared to the other two groups (P = 0.006). In multivariate analysis only the radiotherapy dose remains as the only statistical significant factor affecting the survival with hazard ratio 0.372 and confidence interval (0.147-0.726). Conclusion: Despite the limitation of our retrospective study, it is worth considering CRT approach for patients with advanced and metastatic NSCLC - not suitable for radical treatment - who have not progressed on chemotherapy.

  16. Calcium signaling as a mediator of cell energy demand and a trigger to cell death.

    Science.gov (United States)

    Bhosale, Gauri; Sharpe, Jenny A; Sundier, Stephanie Y; Duchen, Michael R

    2015-09-01

    Calcium signaling is pivotal to a host of physiological pathways. A rise in calcium concentration almost invariably signals an increased cellular energy demand. Consistent with this, calcium signals mediate a number of pathways that together serve to balance energy supply and demand. In pathological states, calcium signals can precipitate mitochondrial injury and cell death, especially when coupled to energy depletion and oxidative or nitrosative stress. This review explores the mechanisms that couple cell signaling pathways to metabolic regulation or to cell death. The significance of these pathways is exemplified by pathological case studies, such as those showing loss of mitochondrial calcium uptake 1 in patients and ischemia/reperfusion injury.

  17. The effect of adenovirus-mediated gene expression of FHIT in small cell lung cancer cells

    DEFF Research Database (Denmark)

    Zandi, Roza; Xu, Kai; Poulsen, Hans S;

    2011-01-01

    The candidate tumor suppressor fragile histidine traid (FHIT) is frequently inactivated in small cell lung cancer (SCLC). Mutations in the p53 gene also occur in the majority of SCLC leading to the accumulation of the mutant protein. Here we evaluated the effect of FHIT gene therapy alone...... or in combination with the mutant p53-reactivating molecule, PRIMA-1(Met)/APR-246, in SCLC. Overexpression of FHIT by recombinant adenoviral vector (Ad-FHIT)-mediated gene transfer in SCLC cells inhibited their growth by inducing apoptosis and when combined with PRIMA-1(Met)/APR-246, a synergistic cell growth...

  18. Cytomegalovirus-Infected Cells Resist T Cell Mediated Killing in an HLA-Recognition Independent Manner.

    Science.gov (United States)

    Proff, Julia; Walterskirchen, Christian; Brey, Charlotte; Geyeregger, Rene; Full, Florian; Ensser, Armin; Lehner, Manfred; Holter, Wolfgang

    2016-01-01

    In order to explore the potential of HLA-independent T cell therapy for human cytomegalovirus (HCMV) infections, we developed a chimeric antigen receptor (CAR) directed against the HCMV encoded glycoprotein B (gB), which is expressed at high levels on the surface of infected cells. T cells engineered with this anti-gB CAR recognized HCMV-infected cells and released cytokines and cytotoxic granules. Unexpectedly, and in contrast to analogous approaches for HIV, Hepatitis B or Hepatitis C virus, we found that HCMV-infected cells were resistant to killing by the CAR-modified T cells. In order to elucidate whether this phenomenon was restricted to the use of CARs, we extended our experiments to T cell receptor (TCR)-mediated recognition of infected cells. To this end we infected fibroblasts with HCMV-strains deficient in viral inhibitors of antigenic peptide presentation and targeted these HLA-class I expressing peptide-loaded infected cells with peptide-specific cytotoxic T cells (CTLs). Despite strong degranulation and cytokine production by the T cells, we again found significant inhibition of lysis of HCMV-infected cells. Impairment of cell lysis became detectable 1 day after HCMV infection and gradually increased during the following 3 days. We thus postulate that viral anti-apoptotic factors, known to inhibit suicide of infected host cells, have evolved additional functions to directly abrogate T cell cytotoxicity. In line with this hypothesis, CAR-T cell cytotoxicity was strongly inhibited in non-infected fibroblasts by expression of the HCMV-protein UL37x1, and even more so by additional expression of UL36. Our data extend the current knowledge on Betaherpesviral evasion from T cell immunity and show for the first time that, beyond impaired antigen presentation, infected cells are efficiently protected by direct blockade of cytotoxic effector functions through viral proteins.

  19. Measurement of cell mediated cytotoxicity by post-labeling surviving target cells

    International Nuclear Information System (INIS)

    The 51Cr release assay (CRA) is the commonly accepted technique for measurement of cell mediated cytotoxicity. This assay shows some disadvantages when mononucleated cells of human peripheral blood (MNC) are used as effector and target cells. The uptake of 51Cr by PHA stimulated lymphocytes is low compared to the spontaneous release. In an attempt to develop a cytotoxicity assay suitable for human lymphocytes we used 14C-TdR to label target cells surviving after contact with effector cells. Cytotoxic lymphocytes were generated by incubation of MNC with irradiated allogeneic MNC for 6 days. On day 6 the effector cells are irradiated and cocultured with PHA stimulated target cells. Twenty-four hours later 14C-TdR is added. After an additional 24 h the cultures are harvested and 14C-TdR taken up by target cells is measured. It is shown that the effector cells are still cytotoxic after irradiation. These cells do not take up 14C-TdR. Cell-free supernatants do not influence the uptake of 14C-TdR by target cells. The results obtained with this assay correlate very well those obtained by the CRA, if the spontaneous release does not exceed 30%. (author)

  20. Neutrophil mediated smooth muscle cell loss precedes allograft vasculopathy

    Directory of Open Access Journals (Sweden)

    Lee Timothy DG

    2010-06-01

    Full Text Available Abstract Background Cardiac allograft vasculopathy (AV is a pathological process of vascular remodeling leading to late graft loss following cardiac transplantation. While there is consensus that AV is alloimmune mediated, and evidence that the most important alloimmune target is medial smooth muscle cells (SMC, the role of the innate immune response in the initiation of this disease is still being elucidated. As ischemia reperfusion (IR injury plays a pivotal role in the initiation of AV, we hypothesize that IR enhances the early innate response to cardiac allografts. Methods Aortic transplants were performed between fully disparate mouse strains (C3H/HeJ and C57BL/6, in the presence of therapeutic levels of Cyclosporine A, as a model for cardiac AV. Neutrophils were depleted from some recipients using anti-PMN serum. Grafts were harvested at 1,2,3,5d and 1,2wk post-transplant. Ultrastructural integrity was examined by transmission electron microscopy. SMC and neutrophils were quantified from histological sections in a blinded manner. Results Grafts exposed to cold ischemia, but not transplanted, showed no medial SMC loss and normal ultrastructural integrity. In comparison, allografts harvested 1d post-transplant exhibited > 90% loss of SMC (p Conclusions These novel data show that there is extensive damage to medial SMC at 1d post-transplant. By depleting neutrophils from recipients it was demonstrated that a portion of the SMC loss was mediated by neutrophils. These results provide evidence that IR activation of early innate events contributes to the etiology of AV.

  1. Radiation therapy for consolidation of metastatic or recurrent sarcomas in children treated with intensive chemotherapy and stem cell rescue. A feasibility study

    International Nuclear Information System (INIS)

    Purpose: To assess the role of consolidative radiation therapy (CRT) in conjunction with myeloablative therapy with or without total body irradiation (TBI) in children and young adults with metastatic or recurrent sarcoma. Methods and Materials: Twenty-one pediatric sarcoma patients with metastatic or recurrent disease were entered on a prospective feasibility study of intensive myeloablative therapy with or without TBI. Median patient age was 17.8 years (range, 9.4-24.7 years). Primary histologies included Ewing's, PNET, and other soft tissue sarcomas. Twenty patients received induction chemotherapy. Myeloablative therapy consisted of TBI in 11 patients with either high dose melphalan/etoposide or high dose cytoxan/thiotepa. TBI consisted of 12 Gy in 2 Gy fractions delivered twice daily over 3 days. Ten patients received high dose chemotherapy alone, either with thiotepa/carboplatinum/etoposide or cytoxan/carboplatinum. Myeloablative therapy was followed by autologous stem cell rescue (ASCR) 24 to 48 hours after completing chemotherapy. Fourteen patients (67%) received CRT either prior to or following myeloablative therapy. Median CRT dose was 37.2 Gy (range, 20-60). Fifty-one disease sites were present prior to myeloablative therapy. Twelve (24%) were bulky (> 8 cm) and 18 (35%) underwent surgical debulking. The median follow-up of surviving patients was 15 months (range, 8-20) with 25% of patients having been followed for more than 20 months. Results: The 3-year actuarial disease-free (DFS) and overall survival (OS) rates for the entire group were 36% and 27%, respectively. Following myeloablative treatment, responses were: 11 complete, 6 partial, 1 stable, and 3 progressive disease. Sixteen patients (71%) have relapsed. The most common site of relapse was the lung. Of the 51 disease sites present prior to myeloablative therapy, 36 sites (71%) were amenable to CRT. Non-amenable sites were: multiple lung metastases and bone marrow. Twenty-six amenable sites (51

  2. Roscovitine suppresses CD4+ T cells and T cell-mediated experimental uveitis.

    Directory of Open Access Journals (Sweden)

    Zili Zhang

    Full Text Available BACKGROUND: T cells are essential for the development of uveitis and other autoimmune diseases. After initial activation, CD4+ lymphocytes express the co-stimulatory molecule OX40 that plays an important role in T cell proliferation. Cyclin dependent kinase 2 (CdK2 plays a pivotal role in the cell cycle transition from G1 to S phase. In addition, recent research has implicated CdK2 in T cell activation. Thus, we sought to test the immunosuppressive effect of roscovitine, a potent CdK2 inhibitor, on CD4+ T cell activation, proliferation, and function. DESIGN AND METHODS: Mouse CD4+ T cells were activated by anti-CD3 and anti-CD28 antibodies. The expression of OX40, CD44, and CdK2 were analyzed by flow cytometry. In addition, cell cycle progression and apoptosis of control and roscovitine-treated T lymphocytes were measured by BrdU incorporation and annexin V assay, respectively. Furthermore, the immunoregulatory effect of roscovitine was evaluated in both ovalbumin-induced uveitis and experimental autoimmune uveitis (EAU models. RESULTS: In this study, we found that T cell activation induced OX40 expression. Cell cycle analysis showed that more CD4+OX40+ cells entered S phase than OX40- T cells. Concurrently, CD4+OX40+ cells had a higher level of CdK2 expression. Roscovitine treatment blocked activated CD4+ cells from entering S phase. In addition, roscovitine not only reduced the viability of CD4+ lymphocytes but also suppressed T cell activation and cytokine production. Finally, roscovitine significantly attenuated the severity of T cell-dependent, OX40-enhanced uveitis. CONCLUSION: These results implicate CdK2 in OX40-augmented T cell response and expansion. Furthermore, this study suggests that roscovitine is a novel, promising, therapeutic agent for treating T cell-mediated diseases such as uveitis.

  3. Consolidation modeling of oilsand tailings

    Energy Technology Data Exchange (ETDEWEB)

    Pollock, G. [AMEC Earth and Environmental Ltd., Calgary, AB (Canada)

    2004-07-01

    Sand consolidation was discussed with reference to modeling sand consolidation, its limitations, opportunities and challenges. Consolidation is the process of soil densification where water is squeezed out of the soil matrix because of added load. The added load comes from additional tailings during filling or additional surcharge. Consolidation provides planners with a tool to predict the quantities of solids and water that a tailings pond will ultimately be required to hold. Consolidation modeling is used in mines all over world, in the dredging industry, and where there is loading of very soft soils. This presentation described how to model consolidation, including input planning parameters and tailings parameters. It provided a summary of a Syncrude consolidated tailings (CT) prototype and compared CT versus mature fine tailings (MFT), versus thickened tailings (TT). It was concluded that finite strain consolidation modeling provides a useful tool for tailings pond planning; consolidation modeling provides opportunity for field measurements which calibrate model; consolidation modeling is very useful for determining end product after reclamation loading; and presently CT is easier to model than mature fine tailings. tabs., figs.

  4. Effect of adrenotensin on cell proliferation is mediated by angiotensin Ⅱ in cultured rat mesangial cells

    Institute of Scientific and Technical Information of China (English)

    Hong XUE; Ping YUAN; Li ZHOU; Tai YAO; Yu HUANG; Li-min LU

    2009-01-01

    Aim: Both adrenomedullin (ADM) and adrenotensin (ADT) are derived from the same propeptide precursor, and both act as circulat- ing hormones and local paracrine mediators with multiple biological activities. Compared with ADM, little is known about how ADT achieves its functions. In the present study, we investigated the effect of ADT on cell proliferation and transforming growth factor-β (TGF-β) secretion in cultured renal mesangial cells (MCs) and determined whether angiotensin Ⅱ (Ang Ⅱ) was involved in mediating this process.Methods: Cell proliferation was measured by bromodeoxyuridine (BrdU) incorporation assay, Ang Ⅱ levels were assayed using an enzyme immunoassay, and real time PCR was used to measure Ang Ⅱ type 1 (AT1) receptor, Ang Ⅱ type 2 (AT2) receptor, angiotensino-gen (AGT), renin, angiotensin converting enzyme (ACE) and TGF-β1 mRNA levels. TGF-β1 and collagen type IV protein levels in cellmedia were measured using enzyme-linked immunoassays. Results: ADT treatment induced cell proliferation in a concentration-dependent manner; it also increased the levels of TGF-β1 mRNA and protein as well as collagen type Ⅳ excretion by cultured MCs. ADT treatment increased renin and AGT mRNAs as well as Ang Ⅱ protein, but did not affect the ACE mRNA level. ADT up-regulated angiotensin AT1 receptor mRNA, but not that of the AT2 receptor. The angiotensin AT1 receptor antagonist Iosartan blocked the effects of ADT-induced cell proliferation, TGF-β1 and collagen type Ⅳ synthe-sis and secretion.Conclusion: ADT has a stimulating role in cell proliferation in cultured MCs. Increases in the levels of Ang II and the AT1 receptor after ADT treatment mediate the stimulating effects of ADT on cell proliferation and extracellular matrix synthesis and secretion.

  5. Software Vulnerability Taxonomy Consolidation

    Energy Technology Data Exchange (ETDEWEB)

    Polepeddi, S

    2004-12-08

    In today's environment, computers and networks are increasing exposed to a number of software vulnerabilities. Information about these vulnerabilities is collected and disseminated via various large publicly available databases such as BugTraq, OSVDB and ICAT. Each of these databases, individually, do not cover all aspects of a vulnerability and lack a standard format among them, making it difficult for end-users to easily compare various vulnerabilities. A central database of vulnerabilities has not been available until today for a number of reasons, such as the non-uniform methods by which current vulnerability database providers receive information, disagreement over which features of a particular vulnerability are important and how best to present them, and the non-utility of the information presented in many databases. The goal of this software vulnerability taxonomy consolidation project is to address the need for a universally accepted vulnerability taxonomy that classifies vulnerabilities in an unambiguous manner. A consolidated vulnerability database (CVDB) was implemented that coalesces and organizes vulnerability data from disparate data sources. Based on the work done in this paper, there is strong evidence that a consolidated taxonomy encompassing and organizing all relevant data can be achieved. However, three primary obstacles remain: lack of referencing a common ''primary key'', un-structured and free-form descriptions of necessary vulnerability data, and lack of data on all aspects of a vulnerability. This work has only considered data that can be unambiguously extracted from various data sources by straightforward parsers. It is felt that even with the use of more advanced, information mining tools, which can wade through the sea of unstructured vulnerability data, this current integration methodology would still provide repeatable, unambiguous, and exhaustive results. Though the goal of coalescing all available data

  6. Software Vulnerability Taxonomy Consolidation

    Energy Technology Data Exchange (ETDEWEB)

    Polepeddi, Sriram S. [Carnegie Mellon Univ., Pittsburgh, PA (United States)

    2004-12-07

    In today's environment, computers and networks are increasing exposed to a number of software vulnerabilities. Information about these vulnerabilities is collected and disseminated via various large publicly available databases such as BugTraq, OSVDB and ICAT. Each of these databases, individually, do not cover all aspects of a vulnerability and lack a standard format among them, making it difficult for end-users to easily compare various vulnerabilities. A central database of vulnerabilities has not been available until today for a number of reasons, such as the non-uniform methods by which current vulnerability database providers receive information, disagreement over which features of a particular vulnerability are important and how best to present them, and the non-utility of the information presented in many databases. The goal of this software vulnerability taxonomy consolidation project is to address the need for a universally accepted vulnerability taxonomy that classifies vulnerabilities in an unambiguous manner. A consolidated vulnerability database (CVDB) was implemented that coalesces and organizes vulnerability data from disparate data sources. Based on the work done in this paper, there is strong evidence that a consolidated taxonomy encompassing and organizing all relevant data can be achieved. However, three primary obstacles remain: lack of referencing a common ''primary key'', un-structured and free-form descriptions of necessary vulnerability data, and lack of data on all aspects of a vulnerability. This work has only considered data that can be unambiguously extracted from various data sources by straightforward parsers. It is felt that even with the use of more advanced, information mining tools, which can wade through the sea of unstructured vulnerability data, this current integration methodology would still provide repeatable, unambiguous, and exhaustive results. Though the goal of coalescing all available data

  7. Cell surface molecules and fibronectin-mediated cell adhesion: effect of proteolytic digestion of membrane proteins

    OpenAIRE

    1982-01-01

    Proteases have been used as a tool to investigate the role of surface molecules in fibronectin-mediated cell adhesion. Proteolytic digestion of membrane-proteins by pronase (1 mg/ml for 20 min at 37 degrees C) completely inhibited adhesion of baby hamster kidney (BHK) fibroblasts on fibronectin-coated plastic dishes. Various degrees of inhibition were also obtained after treatment with proteinase K, chymotrypsin, papain, subtilopeptidase A, and thermolysin. Protein synthesis was required to r...

  8. GILT - A randomised phase III study of oral vinorelbine and cisplatin with concomitant radiotherapy followed by either consolidation therapy with oral vinorelbine and cisplatin or best supportive care alone in stage III non-small cell lung cancer

    Energy Technology Data Exchange (ETDEWEB)

    Flentje, Michael [University Hospital Wuerzburg, Dept. of Radiotherapy, Wuerzburg (Germany); Huber, Rudolf M. [University Hospital Munich, Member of the German Center for Lung Research (DZL CPC-M), Munich (Germany); Engel-Riedel, Walburga [University Hospital Merheim, Dept. of Pneumonology, Cologne (Germany); Andreas, Stefan [Dept. of Pneumonology, Immenhausen (Germany); Kollmeier, Jens [Helios Emil-von-Behring Hospital, Berlin (Germany); Staar, Susanne [Municipal Hospital Bremen-Mitte, Bremen (Germany); Dickgreber, Nicolas [University Hospital Hannover, Hannover (Germany); Vaissiere, Nathalie; Almeida, Cecilia de [Institut de Recherche Pierre Fabre, Boulogne (France); Edlich, Birgit [Pierre Fabre Pharma GmbH, Freiburg (Germany); Fietkau, Rainer [University Hospital Erlangen, Erlangen (Germany)

    2016-04-15

    Concurrent chemoradiotherapy (CRT) is considered standard for inoperable stage III non-small cell lung cancer (NSCLC). Consolidation chemotherapy (CC) following CRT is intended to further improve outcomes, yet studies have shown discordant results. This phase III study assessed CRT followed by best supportive care (BSC) or consolidation with oral vinorelbine and cisplatin. Patients received two cycles of oral vinorelbine (50 mg/m{sup 2} days 1, 8 and 15) + cisplatin (20 mg/m{sup 2} days 1-4) q4w + radiotherapy (RT; 66 Gy). Patients with at least stable disease (SD) were randomised to either two cycles oral vinorelbine (60-80 mg/m{sup 2} days 1 and 8) + cisplatin (80 mg/m{sup 2} day 1) q3w + BSC or BSC alone. Primary endpoint was progression-free survival (PFS). A total of 279 patients were enrolled for CRT and 201 patients were randomised to CC or BSC. Both CRT and CC were well tolerated, with limited radiation-mediated grade 3/4 toxicities (CRT/CC/BSC: oesophagitis-related events 12.9 %/3.1 %/0 %; grade 3 pneumonitis 0 %/0 %/2 %) and chemotherapy-mediated grade 3/4 toxicities (CRT/CC: neutropenia 11.2 %/22.1 %; leukopenia 18.3 %/26.7 %; grade 3 nausea 5.0 %/2.3 %, grade 3 vomiting 3.2 %/3.5 %). Median PFS from randomisation was 6.4 (5.0-8.7) and 5.5 (3.8-7.4) months in the CC and BSC arms (hazard ratio, HR = 0.93 [0.69-1.26]; p = 0.63), respectively; median overall survival (OS) 20.8 (13.5-25.3) and 18.5 (13.6-24.7) months, respectively. Consolidation chemotherapy after concurrent CRT did not prolong PFS or OS. Concurrent RT with oral vinorelbine and cisplatin demonstrated a favourable safety profile and represents a suitable treatment regimen for inoperable stage III NSCLC. (orig.) [German] Simultane Radiochemotherapie (CRT) wird als Standardtherapie beim inoperablen Stadium III des nicht-kleinzelligen Lungenkarzinoms (NSCLC) angesehen. Konsolidierende Chemotherapie (CC) nach der CRT zielt darauf ab, das Therapieergebnis zu verbessern, allerdings zeigen Studien

  9. Perfluorooctanesulfonate Mediates Renal Tubular Cell Apoptosis through PPARgamma Inactivation.

    Directory of Open Access Journals (Sweden)

    Li-Li Wen

    Full Text Available Perfluorinated chemicals (PFCs are ubiquitously distributed in the environments including stainless pan-coating, raincoat, fire extinguisher, and semiconductor products. The PPAR family has been shown to contribute to the toxic effects of PFCs in thymus, immune and excretory systems. Herein, we demonstrated that perfluorooctanesulfonate (PFOS caused cell apoptosis through increasing ratio of Bcl-xS/xL, cytosolic cytochrome C, and caspase 3 activation in renal tubular cells (RTCs. In addition, PFOS increased transcription of inflammatory cytokines (i.e., TNFα, ICAM1, and MCP1 by NFκB activation. Conversely, PFOS reduced the mRNA levels of antioxidative enzymes, such as glutathione peroxidase, catalase, and superoxide dismutase, as a result of reduced PPARγ transactivational activity by using reporter and chromatin immuoprecipitation (ChIP assays. PFOS reduced the protein interaction between PPARγ and PPARγ coactivator-1 alpha (PGC1α by PPARγ deacetylation through Sirt1 upregulation, of which the binding of PPARγ and PGC1α to a peroxisome proliferator response element (PPRE in the promoter regions of these antioxidative enzymes was alleviated in the ChIP assay. Furthermore, Sirt1 also deacetylated p53 and then increased the binding of p53 to Bax, resulting in increased cytosolic cytochrome C. The effect of PPARγ inactivation by PFOS was validated using the PPARγ antagonist GW9662, whereas the adverse effects of PFOS were prevented by PPARγ overexpression and activators, rosiglitozone and L-carnitine, in RTCs. The in vitro finding of protective effect of L-carnitine was substantiated in vivo using Balb/c mice model subjected to PFOS challenge. Altogether, we provide in vivo and in vitro evidence for the protective mechanism of L-carnitine in eliminating PFOS-mediated renal injury, at least partially, through PPARγ activation.

  10. Cell mediated therapeutics for cancer treatment: Tumor homing cells as therapeutic delivery vehicles

    Science.gov (United States)

    Balivada, Sivasai

    Many cell types were known to have migratory properties towards tumors and different research groups have shown reliable results regarding cells as delivery vehicles of therapeutics for targeted cancer treatment. Present report discusses proof of concept for 1. Cell mediated delivery of Magnetic nanoparticles (MNPs) and targeted Magnetic hyperthermia (MHT) as a cancer treatment by using in vivo mouse cancer models, 2. Cells surface engineering with chimeric proteins for targeted cancer treatment by using in vitro models. 1. Tumor homing cells can carry MNPs specifically to the tumor site and tumor burden will decrease after alternating magnetic field (AMF) exposure. To test this hypothesis, first we loaded Fe/Fe3O4 bi-magnetic NPs into neural progenitor cells (NPCs), which were previously shown to migrate towards melanoma tumors. We observed that NPCs loaded with MNPs travel to subcutaneous melanoma tumors. After alternating magnetic field (AMF) exposure, the targeted delivery of MNPs by the NPCs resulted in a mild decrease in tumor size (Chapter-2). Monocytes/macrophages (Mo/Ma) are known to infiltrate tumor sites, and also have phagocytic activity which can increase their uptake of MNPs. To test Mo/Ma-mediated MHT we transplanted Mo/Ma loaded with MNPs into a mouse model of pancreatic peritoneal carcinomatosis. We observed that MNP-loaded Mo/Ma infiltrated pancreatic tumors and, after AMF treatment, significantly prolonged the lives of mice bearing disseminated intraperitoneal pancreatic tumors (Chapter-3). 2. Targeted cancer treatment could be achieved by engineering tumor homing cell surfaces with tumor proteases cleavable, cancer cell specific recombinant therapeutic proteins. To test this, Urokinase and Calpain (tumor specific proteases) cleavable; prostate cancer cell (CaP) specific (CaP1 targeting peptide); apoptosis inducible (Caspase3 V266ED3)- rCasp3V266ED3 chimeric protein was designed in silico. Hypothesized membrane anchored chimeric protein (rCasp3V

  11. Consolidated Copayment Processing Center (CCPC)

    Data.gov (United States)

    Department of Veterans Affairs — The Consolidated Copayment Processing Center (CCPC) database contains Veteran patient contact and billing information in order to support the printing and mailing...

  12. Lentivirus-Mediated Knockdown of Myosin VI Inhibits Cell Proliferation of Breast Cancer Cell.

    Science.gov (United States)

    Wang, Hong; Wang, Biyun; Zhu, Wei; Yang, Ziang

    2015-10-01

    Myosin VI (MYO6) is a unique member of the myosin superfamily, and almost no experimental studies link MYO6 to tumorigenesis of breast cancer. However, previous microarray data demonstrated that MYO6 was frequently overexpressed in breast cancer tissues. In this study, to further develop its role in breast cancer, endogenous expression of MYO6 was significantly inhibited in breast cancer ZR-75-30 and MDA-MB-231 cells using lentivirus-mediated RNA interference. Quantitative polymerase chain reaction and western blot were applied to detect the expression level of MYO6. Cell viability of both cell lines was measured by methylthiazol tetrazolium and colony formation assays. Besides, cell cycle assay was utilized to acquire the distribution information of cell phase. The results demonstrated that knockdown of MYO6 markedly reduced cell viability and colony formation, as well as suppressed cell cycle progression in breast cancer cells. The results suggested that MYO6 played a vital role in breast cancer cells and might provide useful information for diagnosis and therapy of human breast cancer in future. PMID:26407123

  13. Dynamic Regulation of Activated Leukocyte Cell Adhesion Molecule–mediated Homotypic Cell Adhesion through the Actin CytoskeletonV⃞

    OpenAIRE

    Nelissen, Judith M. D. T.; Peters, Inge M.; de Grooth, Bart G.; Van Kooyk, Yvette; Figdor, Carl G.

    2000-01-01

    Restricted expression of activated leukocyte cell adhesion molecule (ALCAM) by hematopoietic cells suggests an important role in the immune system and hematopoiesis. To get insight into the mechanisms that control ALCAM-mediated adhesion we have investigated homotypic ALCAM–ALCAM interactions. Here, we demonstrate that the cytoskeleton regulates ALCAM-mediated cell adhesion because inhibition of actin polymerization by cytochalasin D (CytD) strongly induces homotypic ALCAM–ALCAM interactions....

  14. Mesenchymal Stem Cells in Immune-Mediated Bone Marrow Failure Syndromes

    OpenAIRE

    Maria-Christina Kastrinaki; Konstantia Pavlaki; Batsali, Aristea K.; Elisavet Kouvidi; Irene Mavroudi; Charalampos Pontikoglou; Papadaki, Helen A

    2013-01-01

    Immune-mediated bone marrow failure syndromes (BMFS) are characterized by ineffective marrow haemopoiesis and subsequent peripheral cytopenias. Ineffective haemopoiesis is the result of a complex marrow deregulation including genetic, epigenetic, and immune-mediated alterations in haemopoietic stem/progenitor cells, as well as abnormal haemopoietic-to-stromal cell interactions, with abnormal release of haemopoietic growth factors, chemokines, and inhibitors. Mesenchymal stem/stromal cells (MS...

  15. Suppression of Th1-mediated autoimmunity by embryonic stem cell-derived dendritic cells.

    Directory of Open Access Journals (Sweden)

    Tokunori Ikeda

    Full Text Available We herein demonstrate the immune-regulatory effect of embryonic stem cell-derived dendritic cells (ES-DCs using two models of autoimmune disease, namely non-obese diabetic (NOD mice and experimental autoimmune encephalomyelitis (EAE. Treatment of pre-diabetic NOD mice with ES-DCs exerted almost complete suppression of diabetes development during the observation period for more than 40 weeks. The prevention of diabetes by ES-DCs was accompanied with significant reduction of insulitis and decreased number of Th1 and Th17 cells in the spleen. Development of EAE was also inhibited by the treatment with ES-DCs, and the therapeutic effect was obtained even if ES-DCs were administrated after the onset of clinical symptoms. Treatment of EAE-induced mice with ES-DCs reduced the infiltration of inflammatory cells into the spinal cord and suppressed the T cell response to the myelin antigen. Importantly, the ES-DC treatment did not affect T cell response to an exogenous antigen. As the mechanisms underlying the reduction of the number of infiltrating Th1 cells, we observed the inhibition of differentiation and proliferation of Th1 cells by ES-DCs. Furthermore, the expression of VLA-4α on Th1 cells was significantly inhibited by ES-DCs. Considering the recent advances in human induced pluripotent stem cell-related technologies, these results suggest a clinical application for pluripotent stem cell-derived dendritic cells as a therapy for T cell-mediated autoimmune diseases.

  16. Sox17-Mediated XEN Cell Conversion Identifies Dynamic Networks Controlling Cell-Fate Decisions in Embryo-Derived Stem Cells

    Directory of Open Access Journals (Sweden)

    Angela C.H. McDonald

    2014-10-01

    Full Text Available Little is known about the gene regulatory networks (GRNs distinguishing extraembryonic endoderm (ExEn stem (XEN cells from those that maintain the extensively characterized embryonic stem cell (ESC. An intriguing network candidate is Sox17, an essential transcription factor for XEN derivation and self-renewal. Here, we show that forced Sox17 expression drives ESCs toward ExEn, generating XEN cells that contribute to ExEn when placed back into early mouse embryos. Transient Sox17 expression is sufficient to drive this fate change during which time cells transit through distinct intermediate states prior to the generation of functional XEN-like cells. To orchestrate this conversion process, Sox17 acts in autoregulatory and feedforward network motifs, regulating dynamic GRNs directing cell fate. Sox17-mediated XEN conversion helps to explain the regulation of cell-fate changes and reveals GRNs regulating lineage decisions in the mouse embryo.

  17. N-cadherin-mediated cell adhesion restricts cell proliferation in the dorsal neural tube.

    Science.gov (United States)

    Chalasani, Kavita; Brewster, Rachel M

    2011-05-01

    Neural progenitors are organized as a pseudostratified epithelium held together by adherens junctions (AJs), multiprotein complexes composed of cadherins and α- and β-catenin. Catenins are known to control neural progenitor division; however, it is not known whether they function in this capacity as cadherin binding partners, as there is little evidence that cadherins themselves regulate neural proliferation. We show here that zebrafish N-cadherin (N-cad) restricts cell proliferation in the dorsal region of the neural tube by regulating cell-cycle length. We further reveal that N-cad couples cell-cycle exit and differentiation, as a fraction of neurons are mitotic in N-cad mutants. Enhanced proliferation in N-cad mutants is mediated by ligand-independent activation of Hedgehog (Hh) signaling, possibly caused by defective ciliogenesis. Furthermore, depletion of Hh signaling results in the loss of junctional markers. We therefore propose that N-cad restricts the response of dorsal neural progenitors to Hh and that Hh signaling limits the range of its own activity by promoting AJ assembly. Taken together, these observations emphasize a key role for N-cad-mediated adhesion in controlling neural progenitor proliferation. In addition, these findings are the first to demonstrate a requirement for cadherins in synchronizing cell-cycle exit and differentiation and a reciprocal interaction between AJs and Hh signaling.

  18. Consolidating Social Media Strategies

    DEFF Research Database (Denmark)

    Gyimóthy, Szilvia; Munar, Ana Maria; Larson, Mia

    2014-01-01

    This study revisits and integrates the insights of recent studies on emergent social media strategies deployed by destination and event management organisations. In a comparative analysis Munar (2012) identified four generic approaches pursued by national tourism boards in the Nordic region, while...... Gyimóthy & Larson (2014) portrayed three digital value co-creation strategies deployed by festival social media. Both frameworks provided novel analytical typologies which identified a series of categories (mimetic, analytic, immersion, advertising and insourcing, crowdsourcing and community consolidation......). This paper discusses the complementary nature of these conceptual proposals and advances an integrated conceptual framework of social media strategies. Based on the empirical findings of a case study that revisits evolving digital and social media strategies of European DMOs this paper maps the dynamics...

  19. FM consolidation plan

    CERN Document Server

    Nonis, M; CERN. Geneva. TS Department

    2008-01-01

    The average life duration of infrastructure being 30 years, preventive or corrective maintenance is not enough to guarantee the perpetuity of the operation of equipment and installation in order to assure the maintain of the patrimony in a functional state. At CERN, such is the age of the civil engineering infrastructure and the relative technical equipment that urgent and appropriate consolidation programs shall be established. The big number of aged buildings and equipment entails that priorities are defined. This paper realizes a portrait of the actual situation and related problems, based on data extracted from D7i and inventories carried out by TS/FM group; at the same time it defines an interventions planning which optimizes safety aspects and maintenance costs. The timing of these interventions depends on the availability of specific resources.

  20. Multiple host-cell recombination pathways act in Agrobacterium-mediated transformation of plant cells.

    Science.gov (United States)

    Mestiri, Imen; Norre, Frédéric; Gallego, Maria E; White, Charles I

    2014-02-01

    Using floral-dip, tumorigenesis and root callus transformation assays of both germline and somatic cells, we present here results implicating the four major non-homologous and homologous recombination pathways in Agrobacterium-mediated transformation of Arabidopsis thaliana. All four single mutant lines showed similar mild reductions in transformability, but knocking out three of four pathways severely compromised Agrobacterium-mediated transformation. Although integration of T-DNA into the plant genome is severely compromised in the absence of known DNA double-strand break repair pathways, it does still occur, suggesting the existence of other pathways involved in T-DNA integration. Our results highlight the functional redundancy of the four major plant recombination pathways in transformation, and provide an explanation for the lack of strong effects observed in previous studies on the roles of plant recombination functions in transformation.

  1. Effects of bortezomib in sensitizing human prostate cancer cell lines to NK-mediated cytotoxicity

    Institute of Scientific and Technical Information of China (English)

    Wei Hu; Rui-Rui Zheng; Hui-Xia Cui; Dan Yue; Yong Wang; You-Hong Jiang

    2012-01-01

    The proteasome inhibitor,bortezomib,has been demonstrated to sensitize tumor cells to tumor necrosis factor-related apoptosis-inducing ligand (TRAIL)-mediated apoptosis.Natural killer (NK) cells represent potent antitumor effector cells.They also express TRAIL.Therefore.we investigated whether bortezomib could sensitize tumor cells to NK cell-mediated killing,and have the same effect in human prostate cancer cell lines (LNCaP and DU145).We found that bortezomib strongly inhibits proliferation in both cell lines.Furthermore,compared with LNCaP cells,DU 145 cells are more sensitive to bortezomib-induced apoptosis.However,bortezomib is unable to sensitize these two cell lines to NK cell-mediated killing in short-term assays.In long-term assays,we found that killing mediated by activated NK cells following bortezornib treatment leads to greater antitumor effects than either treatment alone.In addition,treatment with bortezomib causes these cells to upregulate apoptosis-related mRNA as well as death receptors and downregulate the major histocompatibility class (MHC)-Ⅰ molecule on the cell surface of DU145 cells.In contrast,LNCaP cells are not sensitized by this treatment.Death receptors and the MHC-Ⅰ molecule did not change in this cell line.These-data suggest that bortezomib can be used to sensitize prostate cancer cells to NK cell-mediated killing and improve current cancer therapies.This therapeutic strategy may be more effective in patients with androgen-insensitive prostate cancer.

  2. Fiscal Consolidations and Heterogeneous Expectations

    NARCIS (Netherlands)

    C. Hommes; J. Lustenhouwer; K. Mavromatis

    2015-01-01

    We analyze fiscal consolidations using a New Keynesian model where agents have heterogeneous expectations and are uncertain about the composition of consoidations. Heterogeneity in expectations may amplify expansions, stabilizing thus the debt-to-GDP ratio faster under tax based consolidations, in t

  3. Remarkable heterogeneity displayed by oval cells in rat and mouse models of stem cell-mediated liver regeneration

    DEFF Research Database (Denmark)

    Jelnes, Peter; Santoni-Rugiu, Eric; Rasmussen, Morten;

    2007-01-01

    the molecular phenotypes of oval cells in several of the most commonly used protocols of stem cell-mediated liver regeneration-namely, treatment with 2-acetylaminofluorene and partial (70%) hepatectomy (AAF/PHx); a choline-deficient, ethionine-supplemented (CDE) diet; a 3,5-diethoxycarbonyl-1,4-dihydro......The experimental protocols used in the investigation of stem cell-mediated liver regeneration in rodents are characterized by activation of the hepatic stem cell compartment in the canals of Hering followed by transit amplification of oval cells and their subsequent differentiation along hepatic...... remarkable phenotypic discrepancies exhibited by oval cells in stem cell-mediated liver regeneration between rats and mice and underline the importance of careful extrapolation between individual species....

  4. Polyol-mediated Synthesis of Chalcogenide Nanoparticles for Thin-film Solar Cells

    OpenAIRE

    Dong, Hailong

    2014-01-01

    The aim of this work was polyol-mediated syntheses of chalcogenide nanoparticles for printable thin-film solar cells. In this thesis, chalcogenide nanoparticles, such as Cu2Se, In2Se3, CZTS, Se@CuSe and Te@Bi2Te3, have been successfully synthesized via a polyol-mediated method.

  5. Inflammatory mediators and cell adhesion molecules as indicators of severity of atherosclerosis: the Rotterdam Study

    NARCIS (Netherlands)

    M.P.M. de Maat (Moniek); M.L. Bots (Michiel); M.M.B. Breteler (Monique); J. Meijer (John); A.J. Kiliaan (Amanda); J.C.M. Witteman (Jacqueline); A. Hofman (Albert)

    2002-01-01

    textabstractInflammatory mediators and soluble cell adhesion molecules predict cardiovascular events. It is not clear whether they reflect the severity of underlying atherosclerotic disease. Within the Rotterdam Study, we investigated the associations of C-reactive protein (CRP), i

  6. MFG-E8 Is Critical for Embryonic Stem Cell-Mediated T Cell Immunomodulation

    Directory of Open Access Journals (Sweden)

    Yuan Tan

    2015-11-01

    Full Text Available The molecules and mechanisms pertinent to the low immunogenicity of undifferentiated embryonic stem cells (ESCs remain poorly understood. Here, we provide evidence that milk fat globule epidermal growth factor 8 (MFG-E8 is a vital mediator in this phenomenon and directly suppresses T cell immune responses. MFG-E8 is enriched in undifferentiated ESCs but diminished in differentiated ESCs. Upregulation of MFG-E8 in ESCs increases the successful engraftment of both undifferentiated and differentiated ESCs across major histocompatibility complex barriers. MFG-E8 suppresses T cell activation/proliferation and inhibits Th1, Th2, and Th17 subpopulations while increasing regulatory T cell subsets. Neutralizing MFG-E8 substantially abrogates these effects, whereas addition of recombinant MFG-E8 to differentiated ESCs restores immunosuppression. Furthermore, we provide the evidence that MFG-E8 suppresses T cell activation and regulates T cell polarization by inhibiting PKCθ phosphorylation through the α3/5βV integrin receptor. Our findings offer an approach to facilitate transplantation acceptance.

  7. Clinical Cancer Therapy by NK Cells via Antibody-Dependent Cell-Mediated Cytotoxicity

    Directory of Open Access Journals (Sweden)

    Kory L. Alderson

    2011-01-01

    Full Text Available Natural killer (NK cells are powerful effector cells that can be directed to eliminate tumor cells through tumor-targeted monoclonal antibodies (mAbs. Some tumor-targeted mAbs have been successfully applied in the clinic and are included in the standard of care for certain malignancies. Strategies to augment the antitumor response by NK cells have led to an increased understanding of how to improve their effector responses. Next-generation reagents, such as molecularly modified mAbs and mAb-cytokine fusion proteins (immunocytokines, ICs designed to augment NK-mediated killing, are showing promise in preclinical and some clinical settings. Continued research into the antitumor effects induced by NK cells and tumor-targeted mAbs suggests that additional intrinsic and extrinsic factors may influence the antitumor response. Therefore more research is needed that focuses on evaluating which NK cell and tumor criteria are best predictive of a clinical response and which combination immunotherapy regimens to pursue for distinct clinical settings.

  8. Positron Emission Tomography/Computed Tomography Findings During Therapy Predict Outcome in Patients With Diffuse Large B-Cell Lymphoma Treated With Chemotherapy Alone but Not in Those Who Receive Consolidation Radiation

    Energy Technology Data Exchange (ETDEWEB)

    Dabaja, Bouthaina S., E-mail: bdabaja@mdanderson.org [Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Hess, Kenneth [Department of Biostatistics, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Shihadeh, Ferial [Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Podoloff, Donald A. [Department of Nuclear Medicine, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Medeiros, L. Jeffrey [Department of Hematopathology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Mawlawi, Osama [Department of Imaging Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Arzu, Isidora [Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Oki, Yasuhiro; Hagemeister, Fredrick B.; Fayad, Luis E. [Department of Lymphoma/Myeloma, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Reed, Valerie K.; Kedir, Aziza; Wogan, Christine F. [Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Rodriguez, Alma [Office of the Executive Vice President and Physician-in-Chief, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States)

    2014-06-01

    Purpose: To assess the value of mid-therapy positron emission tomography (PET) findings for predicting survival and disease progression in patients with diffuse large B-cell lymphoma, considering type of therapy (chemotherapy with or without radiation therapy). Methods and Materials: We retrospectively evaluated 294 patients with histologically confirmed diffuse large B-cell lymphoma with respect to age, sex, disease stage, International Prognostic Index score, mid-therapy PET findings (positive or negative), and disease status after therapy and at last follow-up. Overall survival (OS) and progression-free survival (PFS) were compared according to mid-therapy PET findings. Results: Of the 294 patients, 163 (55%) were male, 144 (49%) were age >61 years, 110 (37%) had stage I or II disease, 219 (74%) had International Prognostic Index score ≤2, 216 (73%) received ≥6 cycles of rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone, and 88 (30%) received consolidation radiation therapy. Five-year PFS and OS rates were associated with mid-therapy PET status: PFS was 78% for those with PET-negative (PET−) disease versus 63% for PET-positive (PET+) disease (P=.024), and OS was 82% for PET− versus 62% for PET+ (P<.002). These associations held true for patients who received chemotherapy only (PFS 71% for PET− vs 52% PET+ [P=.012], OS 78% for PET− and 51% for PET+ [P=.0055]) but not for those who received consolidation radiation therapy (PFS 84% PET− vs 81% PET+ [P=.88]; OS 90% PET− vs 81% PET+ [P=.39]). Conclusion: Mid-therapy PET can predict patient outcome, but the use of consolidation radiation therapy may negate the significance of mid-therapy findings.

  9. NK cell survival mediated through the regulatory synapse with human DCs requires IL-15Rα

    OpenAIRE

    Brilot, Fabienne; Strowig, Till; Roberts, Susanne M.; Arrey, Frida; Münz, Christian

    2007-01-01

    DCs activate NK cells during innate immune responses to viral infections. However, the composition and kinetics of the immunological synapse mediating this interaction are largely unknown. Here, we report the rapid formation of an immunological synapse between human resting NK cells and mature DCs. Although inhibitory NK cell receptors were polarized to this synapse, where they are known to protect mature DCs from NK cell lysis, the NK cell also received activation signals that induced mobili...

  10. Lis1 mediates planar polarity of auditory hair cells through regulation of microtubule organization

    OpenAIRE

    Sipe, Conor W.; Liu, Lixia; Lee, Jianyi; Grimsley-Myers, Cynthia; Lu, Xiaowei

    2013-01-01

    The V-shaped hair bundles atop auditory hair cells and their uniform orientation are manifestations of epithelial planar cell polarity (PCP) required for proper perception of sound. PCP is regulated at the tissue level by a conserved core Wnt/PCP pathway. However, the hair cell-intrinsic polarity machinery is poorly understood. Recent findings implicate hair cell microtubules in planar polarization of hair cells. To elucidate the microtubule-mediated polarity pathway, we analyzed Lis1 functio...

  11. Does abnormal sleep impair memory consolidation in schizophrenia?

    Directory of Open Access Journals (Sweden)

    Dara S Manoach

    2009-09-01

    Full Text Available Although disturbed sleep is a prominent feature of schizophrenia, its relation to the pathophysiology, signs, and symptoms of schizophrenia remains poorly understood. Sleep disturbances are well known to impair cognition in healthy individuals. Yet, in spite of its ubiquity in schizophrenia, abnormal sleep has generally been overlooked as a potential contributor to cognitive deficits. Amelioration of cognitive deficits is a current priority of the schizophrenia research community, but most efforts to define, characterize, and quantify cognitive deficits focus on cross-sectional measures. While this approach provides a valid snapshot of function, there is now overwhelming evidence that critical aspects of learning and memory consolidation happen offline, both over time and with sleep. Initial memory encoding is followed by a prolonged period of consolidation, integration, and reorganization, that continues over days or even years. Much of this evolution of memories is mediated by sleep. This article briefly reviews (i abnormal sleep in schizophrenia, (ii sleep-dependent memory consolidation in healthy individuals, (iii recent findings of impaired sleep-dependent memory consolidation in schizophrenia, and (iv implications of impaired sleep-dependent memory consolidation in schizophrenia. This literature suggests that abnormal sleep in schizophrenia disrupts attention and impairs sleep-dependent memory consolidation and task automation. We conclude that these sleep-dependent impairments may contribute substantially to generalized cognitive deficits in schizophrenia. Understanding this contribution may open new avenues to ameliorating cognitive dysfunction and thereby improve outcome in schizophrenia.

  12. Childhood adversity and cell-mediated immunity in young adulthood: Does type and timing matter?

    OpenAIRE

    Slopen, Natalie; McLaughlin, Katie A.; Erin C Dunn; Koenen, Karestan C.

    2012-01-01

    Childhood adversity can have powerful effects on health over the life course. Persistent changes in cell-mediated immune function may be one pathway linking adverse childhood experiences with later disease risk. However, limited research has examined childhood adversity in relation to cell-mediated immune function, and in particular, immune response to latent viruses in adulthood. The present study investigated the association of two types of childhood adversity, socioeconomic disadvantage du...

  13. Autophagic Cell Death and Apoptosis Jointly Mediate Cisatracurium Besylate-Induced Cell Injury

    Directory of Open Access Journals (Sweden)

    Haixia Zhuang

    2016-04-01

    Full Text Available Cisatracurium besylate is an ideal non-depolarizing muscle relaxant which is widely used in clinical application. However, some studies have suggested that cisatracurium besylate can affect cell proliferation. Moreover, its specific mechanism of action remains unclear. Here, we found that the number of GFP-LC3 (green fluoresent protein-light chain 3 positive autophagosomes and the rate of mitochondria fracture both increased significantly in drug-treated GFP-LC3 and MitoDsRed stable HeLa cells. Moreover, cisatracurium promoted the co-localization of LC3 and mitochondria and induced formation of autolysosomes. Levels of mitochondrial proteins decreased, which were reversed by the lysosome inhibitor Bafinomycin A1. Similar results with evidence of dose-dependent effects were found in both HeLa and Human Umbilical Vein Endothelial Cells (HUVECs. Cisatracurium lowered HUVEC viability to 0.16 (OD490 at 100 µM and to 0.05 (OD490 after 48 h in vitro; it increased the cell death rate to 56% at 100 µM and to 60% after 24 h in a concentration- and time-dependent manner (p < 0.01. Cell proliferation decreased significantly by four fold in Atg5 WT (wildtype MEF (mouse embryonic fibroblast (p < 0.01 but was unaffected in Atg5 KO (Knockout MEF, even upon treatment with a high dose of cisatracurium. Cisatracurium induced significant increase in cell death of wild-type MEFs even in the presence of the apoptosis inhibitor zVAD. Thus, we conclude that activation of both the autophagic cell death and cell apoptosis pathways contributes to cisatracurium-mediated cell injury.

  14. Thymoquinone inhibits autophagy and induces cathepsin-mediated, caspase-independent cell death in glioblastoma cells.

    Directory of Open Access Journals (Sweden)

    Ira O Racoma

    Full Text Available Glioblastoma is the most aggressive and common type of malignant brain tumor in humans, with a median survival of 15 months. There is a great need for more therapies for the treatment of glioblastoma. Naturally occurring phytochemicals have received much scientific attention because many exhibit potent tumor killing action. Thymoquinone (TQ is the bioactive compound of the Nigella sativa seed oil. TQ has anti-oxidant, anti-inflammatory and anti-neoplastic actions with selective cytotoxicity for human cancer cells compared to normal cells. Here, we show that TQ selectively inhibits the clonogenicity of glioblastoma cells as compared to normal human astrocytes. Also, glioblastoma cell proliferation could be impaired by chloroquine, an autophagy inhibitor, suggesting that glioblastoma cells may be dependent on the autophagic pathway for survival. Exposure to TQ caused an increase in the recruitment and accumulation of the microtubule-associated protein light chain 3-II (LC3-II. TQ also caused an accumulation of the LC3-associated protein p62, confirming the inhibition of autophagy. Furthermore, the levels of Beclin-1 protein expression were unchanged, indicating that TQ interferes with a later stage of autophagy. Finally, treatment with TQ induces lysosome membrane permeabilization, as determined by a specific loss of red acridine orange staining. Lysosome membrane permeabilization resulted in a leakage of cathepsin B into the cytosol, which mediates caspase-independent cell death that can be prevented by pre-treatment with a cathepsin B inhibitor. TQ induced apoptosis, as determined by an increase in PI and Annexin V positive cells. However, apoptosis appears to be caspase-independent due to failure of the caspase inhibitor z-VAD-FMK to prevent cell death and absence of the typical apoptosis related signature DNA fragmentation. Inhibition of autophagy is an exciting and emerging strategy in cancer therapy. In this vein, our results describe a

  15. Adenovirus-mediated transfection with glucose transporter 3 suppresses PC12 cell apoptosis following ischemic injury

    Institute of Scientific and Technical Information of China (English)

    Junliang Li; Xinke Xu; Shanyi Zhang; Meiguang Zheng; Zhonghua Wu; Yinlun Weng; Leping Ouyang; Jian Yu; Fangcheng Li

    2012-01-01

    In this study, we investigated the effects of adenovirus-mediated transfection of PC12 cells with glucose transporter 3 after ischemic injury. The results of flow cytometry and TUNEL showed that exogenous glucose transporter 3 significantly suppressed PC12 cell apoptosis induced by ischemic injury. The results of isotopic scintiscan and western blot assays showed that, the glucose uptake rate was significantly increased and nuclear factor kappaB expression was significantly decreased after adenovirus-mediated transfection of ischemic PC12 cells with glucose transporter 3. These results suggest that adenovirus-mediated transfection of cells with glucose transporter 3 elevates the energy metabolism of PC12 cells with ischemic injury, and inhibits cell apoptosis.

  16. UV laser mediated cell selective destruction by confocal microscopy

    Directory of Open Access Journals (Sweden)

    Giangrande Angela

    2008-04-01

    Full Text Available Abstract Analysis of cell-cell interactions, cell function and cell lineages greatly benefits selective destruction techniques, which, at present, rely on dedicated, high energy, pulsed lasers and are limited to cells that are detectable by conventional microscopy. We present here a high resolution/sensitivity technique based on confocal microscopy and relying on commonly used UV lasers. Coupling this technique with time-lapse enables the destruction and following of any cell(s in any pattern(s in living animals as well as in cell culture systems.

  17. Numerical Modeling of Microbial Fuel Cell Based on Redox Electron Mediator

    Institute of Scientific and Technical Information of China (English)

    Nanqi Ren

    2015-01-01

    To investigate the behavior of redox electron mediator and its impact to power generation of microbial fuel cell ( MFC ) , this study carries out the numerical modeling of a typical two⁃chamber MFC based on assumption of interfacial electron transfer via redox electron mediator and acetate as sole electron donor. The model simulates the development of cell voltage, current, substrate concentration, redox electron mediator concentration, polarization and power density output under defined conditions. The results demonstrate that the developed models can fit the experimental results well on a qualitative basis, and concentration of electron reduced mediator plays a dominant role in electron transfer process, and the mass transfer may constitute the limiting step when its concentration is at a relatively low level. This study not only provides a better understanding of electron redox mediator behavior during power generation, but also suggests a strategy to improve electron transfer in the anode of MFC.

  18. Separation of effector cells mediating antibody-dependent cellular cytotoxicity (ADC) to erythrocyte targets from those mediating ADC to tumor targets.

    Science.gov (United States)

    Pollack, S B; Nelson, K; Grausz, J D

    1976-04-01

    Murine spleen cells mediate antibody-dependent cellular cytotoxicity (ADC) both to erythrocyte targets in a 51Cr release assay and to syngeneic tumor targets in a microcytotoxicity assay. The effector cells active in the two ADC assays can be separated by passage of the spleen cells through columns of Sephadex G-10 at 37 degrees C. Cells mediating ADC to sarcoma cells did not adhere to the G-10 and were recovered in the column effluent. These nonadherent cells were not cytotoxic to antibody-coated chicken red blood cells. Spleen cells which mediated ADC in a 51Cr release assay to the red cell targets adhered to G-10. Adherent effector cells could subsequently be recovered from the columns by elution with 5 X 10(-4) M EDTA. PMID:815438

  19. Cell-cycle dependent expression of a translocation-mediated fusion oncogene mediates checkpoint adaptation in rhabdomyosarcoma.

    Science.gov (United States)

    Kikuchi, Ken; Hettmer, Simone; Aslam, M Imran; Michalek, Joel E; Laub, Wolfram; Wilky, Breelyn A; Loeb, David M; Rubin, Brian P; Wagers, Amy J; Keller, Charles

    2014-01-01

    Rhabdomyosarcoma is the most commonly occurring soft-tissue sarcoma in childhood. Most rhabdomyosarcoma falls into one of two biologically distinct subgroups represented by alveolar or embryonal histology. The alveolar subtype harbors a translocation-mediated PAX3:FOXO1A fusion gene and has an extremely poor prognosis. However, tumor cells have heterogeneous expression for the fusion gene. Using a conditional genetic mouse model as well as human tumor cell lines, we show that that Pax3:Foxo1a expression is enriched in G2 and triggers a transcriptional program conducive to checkpoint adaptation under stress conditions such as irradiation in vitro and in vivo. Pax3:Foxo1a also tolerizes tumor cells to clinically-established chemotherapy agents and emerging molecularly-targeted agents. Thus, the surprisingly dynamic regulation of the Pax3:Foxo1a locus is a paradigm that has important implications for the way in which oncogenes are modeled in cancer cells. PMID:24453992

  20. Cell-cycle dependent expression of a translocation-mediated fusion oncogene mediates checkpoint adaptation in rhabdomyosarcoma.

    Directory of Open Access Journals (Sweden)

    Ken Kikuchi

    2014-01-01

    Full Text Available Rhabdomyosarcoma is the most commonly occurring soft-tissue sarcoma in childhood. Most rhabdomyosarcoma falls into one of two biologically distinct subgroups represented by alveolar or embryonal histology. The alveolar subtype harbors a translocation-mediated PAX3:FOXO1A fusion gene and has an extremely poor prognosis. However, tumor cells have heterogeneous expression for the fusion gene. Using a conditional genetic mouse model as well as human tumor cell lines, we show that that Pax3:Foxo1a expression is enriched in G2 and triggers a transcriptional program conducive to checkpoint adaptation under stress conditions such as irradiation in vitro and in vivo. Pax3:Foxo1a also tolerizes tumor cells to clinically-established chemotherapy agents and emerging molecularly-targeted agents. Thus, the surprisingly dynamic regulation of the Pax3:Foxo1a locus is a paradigm that has important implications for the way in which oncogenes are modeled in cancer cells.

  1. T Cell-Mediated Modulation of Mast Cell Function: Heterotypic Adhesion-Induced Stimulatory or Inhibitory Effects

    Directory of Open Access Journals (Sweden)

    Yoseph A. Mekori

    2012-01-01

    Full Text Available Close physical proximity between mast cells and T cells has been demonstrated in several T cell mediated inflammatory processes such as rheumatoid arthritis and sarcoidosis. However, the way by which mast cells are activated in these T cell-mediated immune responses has not been fully elucidated. We have identified and characterized a novel mast cell activation pathway initiated by physical contact with activated T cells, and showed that this pathway is associated with degranulation and cytokine release. The signaling events associated with this pathway of mast cell activation have also been elucidated confirming the activation of the Ras MAPK systems. More recently, we hypothesized and demonstrated that mast cells may also be activated by microparticles released from activated T cells that are considered as miniature version of a cell. By extension, microparticles might affect the activity of mast cells, which are usually not in direct contact with T cells at the inflammatory site. Recent works have also focused on the effects of regulatory T cells on mast cells. These reports highlighted the importance of the cytokines IL-2 and IL-9, produced by mast cells and T cells, respectively, in obtaining optimal immune suppression. Finally, physical contact, associated by OX40-OX40L engagement has been found to underlie the down-regulatory effects exerted by regulatory T cells on mast cell function.

  2. Extracellular Protein Interactions Mediated by the Neural Cell Adhesion Molecule, NCAM: Heterophilic Interactions Between NCAM and Cell Adhesion Molecules, Extracellular Matrix Proteins, and Viruses

    DEFF Research Database (Denmark)

    Nielsen, Janne; Kulahin, Nikolaj; Walmod, Peter

    2008-01-01

    Cell adhesion molecules (CAMs) mediate cell-to-cell interactions and interactions between cells and the extracellular matrix (ECM). The neural cell adhesion molecule (NCAM), a prototypic member of the immunoglobulin (Ig) superfamily of CAMs, mediates adhesion through homophilic and heterophilic i...

  3. The B-cell receptor orchestrates environment-mediated lymphoma survival and drug resistance in B-cell malignancies.

    Science.gov (United States)

    Shain, K H; Tao, J

    2014-08-01

    Specific niches within the lymphoma tumor microenvironment (TME) provide sanctuary for subpopulations of tumor cells through stromal cell-tumor cell interactions. These interactions notably dictate growth, response to therapy and resistance of residual malignant B cells to therapeutic agents. This minimal residual disease (MRD) remains a major challenge in the treatment of B-cell malignancies and contributes to subsequent disease relapse. B-cell receptor (BCR) signaling has emerged as essential mediator of B-cell homing, survival and environment-mediated drug resistance (EMDR). Central to EMDR are chemokine- and integrin-mediated interactions between lymphoma and the TME. Further, stromal cell-B cell adhesion confers a sustained BCR signaling leading to chemokine and integrin activation. Recently, the inhibitors of BCR signaling have garnered a substantial clinical interest because of their effectiveness in B-cell disorders. The efficacy of these agents is, at least in part, attributed to attenuation of BCR-dependent lymphoma-TME interactions. In this review, we discuss the pivotal role of BCR signaling in the integration of intrinsic and extrinsic determinants of TME-mediated lymphoma survival and drug resistance. PMID:24037527

  4. T cell-mediated modulation of mast cell function: heterotypic adhesion-induced stimulatory or inhibitory effects.

    Science.gov (United States)

    Mekori, Yoseph A; Hershko, Alon Y

    2012-01-01

    Close physical proximity between mast cells and T cells has been demonstrated in several T cell mediated inflammatory processes such as rheumatoid arthritis and sarcoidosis. However, the way by which mast cells are activated in these T cell-mediated immune responses has not been fully elucidated. We have identified and characterized a novel mast cell activation pathway initiated by physical contact with activated T cells, and showed that this pathway is associated with degranulation and cytokine release. The signaling events associated with this pathway of mast cell activation have also been elucidated confirming the activation of the Ras mitogen-activated protein kinase systems. More recently, we hypothesized and demonstrated that mast cells may also be activated by microparticles released from activated T cells that are considered as miniature version of a cell. By extension, microparticles might affect the activity of mast cells, which are usually not in direct contact with T cells at the inflammatory site. Recent works have also focused on the effects of regulatory T cells (Treg) on mast cells. These reports highlighted the importance of the cytokines IL-2 and IL-9, produced by mast cells and T cells, respectively, in obtaining optimal immune suppression. Finally, physical contact, associated by OX40-OX40L engagement has been found to underlie the down-regulatory effects exerted by Treg on mast cell function. PMID:22566892

  5. Bone Morphogenetic Protein 4 Mediates Human Embryonic Germ Cell Derivation

    OpenAIRE

    Hiller, Marc; Liu, Cyndi; Blumenthal, Paul D; John D Gearhart; Kerr, Candace L.

    2010-01-01

    Human primordial germ cells (PGCs) have proven to be a source of pluripotent stem cells called embryonic germ cells (EGCs). Unlike embryonic stem cells, virtually little is known regarding the factors that regulate EGC survival and maintenance. In mice, the growth factor bone morphogenetic protein 4 (BMP4) has been shown to be required for maintaining mouse embryonic stem cells, and disruptions in this gene lead to defects in mouse PGC specification. Here, we sought to determine whether recom...

  6. P-selectin-mediated platelet adhesion promotes the metastasis of murine melanoma cells.

    Science.gov (United States)

    Qi, Cui-Ling; Wei, Bo; Ye, Jie; Yang, Yang; Li, Bin; Zhang, Qian-Qian; Li, Jiang-Chao; He, Xiao-Dong; Lan, Tian; Wang, Li-Jing

    2014-01-01

    Studies have indicated that the aggregation of activated platelets with cancer cells facilitates tumor metastasis; the adhesion molecule P-selectin may be an important mediator of this process, but the detailed mechanism is unclear. In the current study, we established a B16F10 (B16) cell metastatic model in P-selectin knockout (P-sel-/-) mice to determine the effect of P-selectin-mediated platelet adhesion on metastasis. Compared with C57 mice, P-sel-/- mice developed fewer metastatic foci, and cell proliferation within the metastatic tumors was inhibited by P-selectin deficiency. The platelet refusion assay demonstrated that mice with P-sel-/- platelets developed fewer lung metastatic foci (PP-selectin deficiency inhibited the metastasis of B16 cells and that wild-type platelet refusion reversed this inhibition. The P-selectin-mediated interaction between platelets and B16 cells promoted angiogenesis by up-regulating VEGF.

  7. Methylanthraquinone from Hedyotis diffusa WILLD induces Ca(2+)-mediated apoptosis in human breast cancer cells.

    Science.gov (United States)

    Liu, Zheng; Liu, Ming; Liu, Miao; Li, Jianchun

    2010-02-01

    Methylanthraquinone from Hedyotis diffusa WILLD exhibited potent anticancer activity in many kinds of cancer cells. However, the exact mechanism and signaling pathway involved in methylanthraquinone-induced apoptosis have not been fully elucidated. Therefore, we explored the mechanisms of methylanthraquinone-mediated apoptosis in MCF-7 human breast cancer cells. When MCF-7 cells were co-incubated with methylanthraquinone, the percentage of apoptotic cell and S phase of cell cycle was markedly increased. In addition, a rise in intracellular calcium levels, phosphorylation of JNK and activation of calpain were found in MCF-7 cells after exposure to methylanthraquinone. With the methylanthraquinone-mediated reduction of mitochondrial membrane potential, cytochrome c was released from mitochondria to cytosol. Moreover, methylanthraquinone strongly induced cleavage of caspase-4, caspase-9 and caspase-7 in MCF-7 cells. These results suggested that methylanthraquinone from Hedyotis diffusa WILLD induced MCF-7 cells apoptosis via Ca(2+)/calpain/caspase-4 pathway. PMID:19686834

  8. UCP2- and non-UCP2-mediated electric current in eukaryotic cells exhibits different properties.

    Science.gov (United States)

    Wang, Ruihua; MoYung, K C; Zhang, M H; Poon, Karen

    2015-12-01

    Using live eukaryotic cells, including cancer cells, MCF-7 and HCT-116, normal hepatocytes and red blood cells in anode and potassium ferricyanide in cathode of MFC could generate bio-based electric current. Electrons and protons generated from the metabolic reaction in both cytosol and mitochondria contributing to the leaking would mediate the generation of electric current. Both resveratrol (RVT) and 2,4-dinitrophenol (DNP) used to induce proton leak in mitochondria were found to promote electric current production in all cells except red blood cells without mitochondria. Proton leak might be important for electric current production by bringing the charge balance in cells to enhance the further electron leak. The induced electric current by RVT can be blocked by Genipin, an inhibitor of UCP2-mediated proton leak, while that induced by DNP cannot. RVT could reduce reactive oxygen species (ROS) level in cells better than that of DNP. In addition, RVT increased mitochondrial membrane potential (MMP), while DNP decreased it. Results highly suggested the existence of at least two types of electric current that showed different properties. They included UCP2-mediated and non-UCP2-mediated electric current. UCP2-mediated electric current exhibited higher reactive oxygen species (ROS) reduction effect per unit electric current production than that of non-UCP2-mediated electric current. Higher UCP2-mediated electric current observed in cancer cells might contribute to the mechanism of drug resistence. Correlation could not be established between electric current production with either ROS and MMP without distinguishing the types of electric current.

  9. Ciprofloxacin mediates cancer stem cell phenotypes in lung cancer cells through caveolin-1-dependent mechanism.

    Science.gov (United States)

    Phiboonchaiyanan, Preeyaporn Plaimee; Kiratipaiboon, Chayanin; Chanvorachote, Pithi

    2016-04-25

    Cancer stem cells (CSCs), a subpopulation of cancer cells with high aggressive behaviors, have been identified in many types of cancer including lung cancer as one of the key mediators driving cancer progression and metastasis. Here, we have reported for the first time that ciprofloxacin (CIP), a widely used anti-microbial drug, has a potentiating effect on CSC-like features in human non-small cell lung cancer (NSCLC) cells. CIP treatment promoted CSC-like phenotypes, including enhanced anchorage-independent growth and spheroid formation. The known lung CSC markers: CD133, CD44, ABCG2 and ALDH1A1 were found to be significantly increased, while the factors involving in epithelial to mesenchymal transition (EMT): Slug and Snail, were depleted. Also, self-renewal transcription factors Oct-4 and Nanog were found to be up-regulated in CIP-treated cells. The treatment of CIP on CSC-rich populations obtained from secondary spheroids resulted in the further increase of CSC markers. In addition, we have proven that the mechanistic insight of the CIP induced stemness is through Caveolin-1 (Cav-1)-dependent mechanism. The specific suppression of Cav-1 by stably transfected Cav-1 shRNA plasmid dramatically reduced the effect of CIP on CSC markers as well as the CIP-induced spheroid formation ability. Cav-1 was shown to activate protein kinase B (Akt) and extracellular signal-regulated kinase (ERK) pathways in CSC-rich population; however, such an effect was rarely found in the main lung cancer cells population. These findings reveal a novel effect of CIP in positively regulating CSCs in lung cancer cells via the activation of Cav-1, Akt and ERK, and may provoke the awareness of appropriate therapeutic strategy in cancer patients.

  10. Listeria monocytogenes alters mast cell phenotype, mediator and osteopontin secretion in a listeriolysin-dependent manner.

    Directory of Open Access Journals (Sweden)

    Catherine E Jobbings

    Full Text Available Whilst mast cells participate in the immune defence against the intracellular bacterium Listeria monocytogenes, there is conflicting evidence regarding the ability of L. monocytogenes to infect mast cells. It is known that the pore-forming toxin listeriolysin (LLO is important for mast cell activation, degranulation and the release of pro-inflammatory cytokines. Mast cells, however, are a potential source of a wide range of cytokines, chemokines and other mediators including osteopontin, which contributes to the clearing of L. monocytogenes infections in vivo, although its source is unknown. We therefore aimed to resolve the controversy of mast cell infection by L. monocytogenes and investigated the extent of mediator release in response to the bacterium. In this paper we show that the infection of bone marrow-derived mast cells by L. monocytogenes is inefficient and LLO-independent. LLO, however, is required for calcium-independent mast cell degranulation as well as for the transient and selective downregulation of cell surface CD117 (c-kit on mast cells. We demonstrate that in addition to the key pro-inflammatory cytokines TNF-α and IL-6, mast cells release a wide range of other mediators in response to L. monocytogenes. Osteopontin, IL-2, IL-4, IL-13 and granulocyte macrophage colony-stimulating factor (GM-CSF, and chemokines including CCL2, CCL3, CCL4 and CCL5 are released in a MyD88-dependent manner. The wide range of mediators released by mast cells in response to L. monocytogenes may play an important role in the recruitment and activation of a variety of immune cells in vivo. The cocktail of mediators, however, is unlikely to skew the immune response to a particular effector response. We propose that mast cells provide a hitherto unreported source of osteopontin, and may provide an important role in co-ordinating the immune response during Listeria infection.

  11. Consolidated Human Activities Database (CHAD)

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Consolidated Human Activity Database (CHAD) contains data obtained from human activity studies that were collected at city, state, and national levels. CHAD is...

  12. Phorbol ester modulation of integrin-mediated cell adhesion: a postreceptor event

    OpenAIRE

    1989-01-01

    Chinese hamster ovary (CHO) suspension culture cells adhere readily to substrata coated with extracellular matrix proteins such as fibronectin, vitronectin, or laminin. In the case of fibronectin, it is known that adhesion is mediated by an integrin-type, cell surface fibronectin receptor (FnR). We demonstrate here that treatment of CHO cells with submicromolar concentrations of phorbol ester produces a remarkable increase in the ability of these cells to adhere to fibronectin. Both the rate ...

  13. CONSOLIDATED FINANCIAL STATEMENTS UNDER IFRS

    OpenAIRE

    Tănase Alin-Eliodor; Calotă Traian-Ovidiu

    2013-01-01

    This article is focuses on accounting consolidation techniques and the preparation of consolidation worksheets for the components of financial statements (statement of comprehensive income, statement of changes in equity, and financial position). The presented group includes parent company, two subsidiaries (only one fully controlled by the parent company) and a jointly controlled entity. The financial statements are presented under the following standards IFRS 3 Business Combination, IAS 27 ...

  14. Specific Btk inhibition suppresses B cell- and myeloid cell-mediated arthritis

    Energy Technology Data Exchange (ETDEWEB)

    Di Paolo, Julie A.; Huang, Tao; Balazs, Mercedesz; Barbosa, James; Barck, Kai H.; Bravo, Brandon J.; Carano, Richard A.D.; Darrow, James; Davies, Douglas R.; DeForge, Laura E.; Diehl, Lauri; Ferrando, Ronald; Gallion, Steven L.; Giannetti, Anthony M.; Gribling, Peter; Hurez, Vincent; Hymowitz, Sarah G.; Jones, Randall; Kropf, Jeffrey E.; Lee, Wyne P.; Maciejewski, Patricia M.; Mitchell, Scott A.; Rong, Hong; Staker, Bart L.; Whitney, J. Andrew; Yeh, Sherry; Young, Wendy B.; Yu, Christine; Zhang, Juan; Reif, Karin; Currie, Kevin S. (CGI); (Emerald); (Genentech)

    2011-09-20

    Bruton's tyrosine kinase (Btk) is a therapeutic target for rheumatoid arthritis, but the cellular and molecular mechanisms by which Btk mediates inflammation are poorly understood. Here we describe the discovery of CGI1746, a small-molecule Btk inhibitor chemotype with a new binding mode that stabilizes an inactive nonphosphorylated enzyme conformation. CGI1746 has exquisite selectivity for Btk and inhibits both auto- and transphosphorylation steps necessary for enzyme activation. Using CGI1746, we demonstrate that Btk regulates inflammatory arthritis by two distinct mechanisms. CGI1746 blocks B cell receptor-dependent B cell proliferation and in prophylactic regimens reduces autoantibody levels in collagen-induced arthritis. In macrophages, Btk inhibition abolishes Fc{gamma}RIII-induced TNF{alpha}, IL-1{beta} and IL-6 production. Accordingly, in myeloid- and Fc{gamma}R-dependent autoantibody-induced arthritis, CGI1746 decreases cytokine levels within joints and ameliorates disease. These results provide new understanding of the function of Btk in both B cell- or myeloid cell-driven disease processes and provide a compelling rationale for targeting Btk in rheumatoid arthritis.

  15. Atherosclerosis: a chronic inflammatory disease mediated by mast cells.

    Science.gov (United States)

    Conti, Pio; Shaik-Dasthagirisaeb, Yazdami

    2015-01-01

    Inflammation is a process that plays an important role in the initiation and progression of atherosclerosis and immune disease, involving multiple cell types, including macrophages, T-lymphocytes, endothelial cells, smooth muscle cells and mast cells. The fundamental damage of atherosclerosis is the atheromatous or fibro-fatty plaque which is a lesion that causes several diseases. In atherosclerosis the innate immune response, which involves macrophages, is initiated by the arterial endothelial cells which respond to modified lipoproteins and lead to Th1 cell subset activation and generation of inflammatory cytokines and chemoattractant chemokines. Other immune cells, such as CD4+ T inflammatory cells, which play a critical role in the development and progression of atherosclerosis, and regulatory T cells [Treg], which have a protective effect on the development of atherosclerosis are involved. Considerable evidence indicates that mast cells and their products play a key role in inflammation and atherosclerosis. Activated mast cells can have detrimental effects, provoking matrix degradation, apoptosis, and enhancement as well as recruitment of inflammatory cells, which actively contributes to atherosclerosis and plaque formation. Here we discuss the relationship between atherosclerosis, inflammation and mast cells. PMID:26648785

  16. Consolidation projections for thickened tailings

    Energy Technology Data Exchange (ETDEWEB)

    Shaw, B. [WHS Engineering Inc., Lakewood, OH (United States); Hyndman, A. [Magnus Ltd., Norwich (United Kingdom); Sobkowicz, J. [Thurber Engineering Ltd., Calgary, AB (Canada)

    2010-07-01

    Fluid fine tailings (FFT) are produced when tailings segregate upon deposition, and when fines and water are separated from tailings. The FFT are stored in ponds. This PowerPoint presentation discussed issues related to the consolidation of FFT as thickened tailings (TT). Tailings grain sizes from various oil sands operations were discussed, as well as beach and dyke construction methods that can lead to the storage and consolidation of FFT. Fines sequestration methods included conventional beaching, mature fine tailings (MFT) centrifugation; and water-capping in pit lakes. Rates of thickened tailings consolidation were considered, as well as methods of constructing enclosure landscapes. Modelling techniques for simulating the consolidation of TT were reviewed. Details of field tests conducted to determine the material properties of TT at several different sites were presented, as well as the results of finite strain consolidation analyses. The study showed that the strength properties of TT are related to effective stress as well as to solids content. While the TT deposits took several years to achieve sufficient consolidation for reclamation purposes, they required less surface area than other methods. tabs., figs. tabs., figs.

  17. TRAIL restores DCA/metformin-mediated cell death in hypoxia.

    Science.gov (United States)

    Hong, Sung-Eun; Kim, Chang Soon; An, Sungkwan; Kim, Hyun-Ah; Hwang, Sang-Gu; Song, Jie-Young; Lee, Jin Kyung; Hong, Jungil; Kim, Jong-Il; Noh, Woo Chul; Jin, Hyeon-Ok; Park, In-Chul

    2016-09-23

    Previous studies have shown that hypoxia can reverse DCA/metformin-induced cell death in breast cancer cells. Therefore, targeting hypoxia is necessary for therapies targeting cancer metabolism. In the present study, we found that TRAIL can overcome the effect of hypoxia on the cell death induced by treatment of DCA and metformin in breast cancer cells. Unexpectedly, DR5 is upregulated in the cells treated with DCA/metformin, and sustained under hypoxia. Blocking DR5 by siRNA inhibited DCA/metformin/TRAIL-induced cell death, indicating that DR5 upregulation plays an important role in sensitizing cancer cells to TRAIL-induced cell death. Furthermore, we found that activation of JNK and c-Jun is responsible for upregulation of DR5 induced by DCA/metformin. These findings support the potential application of combining TRAIL and metabolism-targeting drugs in the treatment of cancers under hypoxia. PMID:27569287

  18. Transplantation tolerance mediated by regulatory T cells in mice

    Institute of Scientific and Technical Information of China (English)

    冯宁翰; 吴宏飞; 吴军; 张炜; 眭元庚; 贺厚光; 张春雷; 郑峻松

    2004-01-01

    Background With potent suppressive effect on responder T cells, CD4+CD25+ regulatory T (Treg) cells have become the focus of attention only recently and they may play an important role in transplantation tolerance. However, the mechanism of action is not clear. This study was designed to assess the possibility of using CD4+CD25+ Treg cells to induce transplantation tolerance and to investigate their mechanism of action.Methods CD4+CD25+ Treg cells were isolated using magnetic cell separation techniques. Mixed lymphocyte reactions were used to assess the ability of Treg cells to suppress effector T cells. Before skin transplantation, various numbers of CD4+CD25+Treg cells, which have been induced using complex skin antigens from the donor, were injected into the host mice either intraperitoneally (0.5×105, 1×105, 2×105, 3×105, 4×105, or 5×105) or by injection through the tail vein (5×103, 1×104, 2×104, 5×104, 1×105, 2×105). Skin grafts from two different donor types were used to assess whether the induced Treg cells were antigen-specific. The survival time of the allografts were observed. Single photon emission computed tomography was also used to determine the distribution of Treg cells before and after transplantation.Results Treg cells have suppressive effect on mixed lymphocyte reactions. Grafts survived longer in mice receiving CD4+CD25+ Treg cell injections than in control mice. There was a significant difference between groups receiving intraperitoneal injection of either 2×105 or 3×105 CD4+CD25+Treg cells and the control group (P<0.05, respectively). Better results were achieved when Treg cells were injected via the tail vein than when injected intraperitoneally. The transplantation tolerance induced by CD4+CD25+ Treg cells was donor-specific. Analysis of the localization of Treg cells revealed that Treg cells mainly migrated from the liver to the allografts and the spleen.Conclusions CD4+CD25+Treg cells can induce donor

  19. Atherosclerosis: a chronic inflammatory disease mediated by mast cells

    OpenAIRE

    Conti, Pio; Shaik-Dasthagirisaeb, Yazdami

    2015-01-01

    Inflammation is a process that plays an important role in the initiation and progression of atherosclerosis and immune disease, involving multiple cell types, including macrophages, T-lymphocytes, endothelial cells, smooth muscle cells and mast cells. The fundamental damage of atherosclerosis is the atheromatous or fibro-fatty plaque which is a lesion that causes several diseases. In atherosclerosis the innate immune response, which involves macrophages, is initiated by the arterial endotheli...

  20. Neuronal inhibition of astroglial cell proliferation is membrane mediated

    OpenAIRE

    1987-01-01

    Previously we have used a microwell tissue culture assay to show that early postnatal mouse cerebellar astroglia have a flattened morphology and proliferate rapidly when they are cultured in the absence of neurons, but develop specific cell-cell contacts and undergo morphological differentiation when they are co-cultured with purified granule neurons (Hatten, M. E., 1985, J. Cell Biol., 100:384-396). In these studies of cell binding between neurons and astroglia, measurement with light and fl...

  1. Interleukin-33-dependent Innate Lymphoid Cells Mediate Hepatic Fibrosis

    OpenAIRE

    Mchedlidze, Tamar; Waldner, Maximilian; Zopf, Steffen; Walker, Jennifer; Rankin, Andrew L.; Schuchmann, Marcus; Voehringer, David; McKenzie, Andrew N.J.; Neurath, Markus F.; Pflanz, Stefan; Wirtz, Stefan

    2013-01-01

    Liver fibrosis is a consequence of chronic liver diseases and thus a major cause of mortality and morbidity. Clinical evidence and animal studies suggest that local tissue homeostasis is disturbed due to immunological responses to chronic hepatocellular stress. Poorly defined stress-associated inflammatory networks are thought to mediate gradual accumulation of extracellular-matrix-components, ultimately leading to fibrosis and liver-failure. Here we have reported that hepatic expression of i...

  2. HaloTag protein-mediated specific labeling of living cells with quantum dots

    International Nuclear Information System (INIS)

    Quantum dots emerge as an attractive alternative to small molecule fluorophores as fluorescent tags for in vivo cell labeling and imaging. This communication presents a method for specific labeling of live cells using quantum dots. The labeling is mediated by HaloTag protein expressed at the cell surface which forms a stable covalent adduct with its ligand (HaloTag ligand). The labeling can be performed in one single step with quantum dot conjugates that are functionalized with HaloTag ligand, or in two steps with biotinylated HaloTag ligand first and followed by streptavidin coated quantum dots. Live cell fluorescence imaging indicates that the labeling is specific and takes place at the cell surface. This HaloTag protein-mediated cell labeling method should facilitate the application of quantum dots for live cell imaging

  3. TRAIL-mediated killing of acute lymphoblastic leukemia by plasmacytoid dendritic cell-activated natural killer cells.

    Science.gov (United States)

    Lelaidier, Martin; Dìaz-Rodriguez, Yildian; Cordeau, Martine; Cordeiro, Paulo; Haddad, Elie; Herblot, Sabine; Duval, Michel

    2015-10-01

    Acute lymphoblastic leukemia (ALL) still frequently recurs after hematopoietic stem cell transplantation (HSCT), underscoring the need to improve the graft-versus-leukemia (GvL) effect. Natural killer (NK) cells reconstitute in the first months following HSCT when leukemia burden is at its lowest, but ALL cells have been shown to be resistant to NK cell-mediated killing. We show here that this resistance is overcome by NK cell stimulation with TLR-9-activated plasmacytoid dendritic cells (pDCs). NK cell priming with activated pDCs resulted in TRAIL and CD69 up-regulation on NK cells and IFN-γ production. NK cell activation was dependent on IFN-α produced by pDCs, but was not reproduced by IFN-α alone. ALL killing was further enhanced by inhibition of KIR engagement. We showed that ALL lysis was mainly mediated by TRAIL engagement, while the release of cytolytic granules was involved when ALL expressed NK cell activating receptor ligands. Finally, adoptive transfers of activated-pDCs in ALL-bearing humanized mice delayed the leukemia onset and cure 30% of mice. Our data therefore demonstrate that TLR-9 activated pDCs are a powerful tool to overcome ALL resistance to NK cell-mediated killing and to reinforce the GvL effect of HSCT. These results open new therapeutic avenues to prevent relapse in children with ALL.

  4. Role of the retinoblastoma protein in cell cycle arrest mediated by a novel cell surface proliferation inhibitor

    Science.gov (United States)

    Enebo, D. J.; Fattaey, H. K.; Moos, P. J.; Johnson, T. C.; Spooner, B. S. (Principal Investigator)

    1994-01-01

    A novel cell regulatory sialoglycopeptide (CeReS-18), purified from the cell surface of bovine cerebral cortex cells has been shown to be a potent and reversible inhibitor of proliferation of a wide array of fibroblasts as well as epithelial-like cells and nontransformed and transformed cells. To investigate the possible mechanisms by which CeReS-18 exerts its inhibitory action, the effect of the inhibitor on the posttranslational regulation of the retinoblastoma susceptibility gene product (RB), a tumor suppressor gene, has been examined. It is shown that CeReS-18 mediated cell cycle arrest of both human diploid fibroblasts (HSBP) and mouse fibroblasts (Swiss 3T3) results in the maintenance of the RB protein in the hypophosphorylated state, consistent with a late G1 arrest site. Although their normal nontransformed counterparts are sensitive to cell cycle arrest mediated by CeReS-18, cell lines lacking a functional RB protein, through either genetic mutation or DNA tumor virus oncoprotein interaction, are less sensitive. The refractory nature of these cells is shown to be independent of specific surface receptors for the inhibitor, and another tumor suppressor gene (p53) does not appear to be involved in the CeReS-18 inhibition of cell proliferation. The requirement for a functional RB protein product, in order for CeReS-18 to mediate cell cycle arrest, is discussed in light of regulatory events associated with density-dependent growth inhibition.

  5. Bacterial-mediated DNA delivery to tumour associated phagocytic cells.

    Science.gov (United States)

    Byrne, W L; Murphy, C T; Cronin, M; Wirth, T; Tangney, M

    2014-12-28

    Phagocytic cells including macrophages, dendritic cells and neutrophils are now recognised as playing a negative role in many disease settings including cancer. In particular, macrophages are known to play a pathophysiological role in multiple diseases and present a valid and ubiquitous therapeutic target. The technology to target these phagocytic cells in situ, both selectively and efficiently, is required in order to translate novel therapeutic modalities into clinical reality. We present a novel delivery strategy using non-pathogenic bacteria to effect gene delivery specifically to tumour-associated phagocytic cells. Non-invasive bacteria lack the ability to actively enter host cells, except for phagocytic cells. We exploit this natural property to effect 'passive transfection' of tumour-associated phagocytic cells following direct administration of transgene-loaded bacteria to tumour regions. Using an in vitro-differentiated human monocyte cell line and two in vivo mouse models (an ovarian cancer ascites and a solid colon tumour model) proof of delivery is demonstrated with bacteria carrying reporter constructs. The results confirm that the delivery strategy is specific for phagocytic cells and that the bacterial vector itself recruits more phagocytic cells to the tumour. While proof of delivery to phagocytic cells is demonstrated in vivo for solid and ascites tumour models, this strategy may be applied to other settings, including non-cancer related disease. PMID:25466954

  6. Effects of verteporfin-mediated photodynamic therapy on endothelial cells

    Science.gov (United States)

    Kraus, Daniel; Chen, Bin

    2015-03-01

    Photodynamic therapy (PDT) is a treatment modality in which cytotoxic reactive oxygen species are generated from oxygen and other biological molecules when a photosensitizer is activated by light. PDT has been approved for the treatment of cancers and age-related macular degeneration (AMD) due to its effectiveness in cell killing and manageable normal tissue complications. In this study, we characterized the effects of verteporfin-PDT on SVEC mouse endothelial cells and determined its underlying cell death mechanisms. We found that verteporfin was primarily localized in mitochondria and endoplasmic reticulum (ER) in SVEC cells. Light treatment of photosensitized SVEC cells induced a rapid onset of cell apoptosis. In addition to significant structural damages to mitochondria and ER, verteporfin-PDT caused substantial degradation of ER signaling molecules, suggesting ER stress. These results demonstrate that verteporfin-PDT triggered SVEC cell apoptosis by both mitochondrial and ER stress pathways. Results from this study may lead to novel therapeutic approaches to enhance PDT outcome.

  7. Secretory phospholipase A2-mediated neuronal cell death involves glutamate ionotropic receptors

    DEFF Research Database (Denmark)

    de Turco, Elena B; Diemer, Nils Henrik; Bazan, Nicolas G;

    2002-01-01

    To define the significance of glutamate ionotropic receptors in sPLA -mediated neuronal cell death we used the NMDA receptor antagonist MK-801 and the AMPA receptor antagonist PNQX. In primary neuronal cell cultures both MK-801 and PNQX inhibited sPLA - and glutamate-induced neuronal death. [ H]A...

  8. Role of macrophage inflammatory protein-1alpha in T-cell-mediated immunity to viral infection

    DEFF Research Database (Denmark)

    Madsen, Andreas N; Nansen, Anneline; Christensen, Jan P;

    2003-01-01

    The immune response to lymphocytic choriomeningitis virus in mice lacking macrophage inflammatory protein-1alpha (MIP-1alpha) was evaluated. Generation of virus-specific effector T cells is unimpaired in MIP-1alpha-deficient mice. Furthermore, MIP-1alpha is not required for T-cell-mediated virus...

  9. Human CAR T cells with cell-intrinsic PD-1 checkpoint blockade resist tumor-mediated inhibition.

    Science.gov (United States)

    Cherkassky, Leonid; Morello, Aurore; Villena-Vargas, Jonathan; Feng, Yang; Dimitrov, Dimiter S; Jones, David R; Sadelain, Michel; Adusumilli, Prasad S

    2016-08-01

    Following immune attack, solid tumors upregulate coinhibitory ligands that bind to inhibitory receptors on T cells. This adaptive resistance compromises the efficacy of chimeric antigen receptor (CAR) T cell therapies, which redirect T cells to solid tumors. Here, we investigated whether programmed death-1-mediated (PD-1-mediated) T cell exhaustion affects mesothelin-targeted CAR T cells and explored cell-intrinsic strategies to overcome inhibition of CAR T cells. Using an orthotopic mouse model of pleural mesothelioma, we determined that relatively high doses of both CD28- and 4-1BB-based second-generation CAR T cells achieved tumor eradication. CAR-mediated CD28 and 4-1BB costimulation resulted in similar levels of T cell persistence in animals treated with low T cell doses; however, PD-1 upregulation within the tumor microenvironment inhibited T cell function. At lower doses, 4-1BB CAR T cells retained their cytotoxic and cytokine secretion functions longer than CD28 CAR T cells. The prolonged function of 4-1BB CAR T cells correlated with improved survival. PD-1/PD-1 ligand [PD-L1] pathway interference, through PD-1 antibody checkpoint blockade, cell-intrinsic PD-1 shRNA blockade, or a PD-1 dominant negative receptor, restored the effector function of CD28 CAR T cells. These findings provide mechanistic insights into human CAR T cell exhaustion in solid tumors and suggest that PD-1/PD-L1 blockade may be an effective strategy for improving the potency of CAR T cell therapies.

  10. Human CAR T cells with cell-intrinsic PD-1 checkpoint blockade resist tumor-mediated inhibition.

    Science.gov (United States)

    Cherkassky, Leonid; Morello, Aurore; Villena-Vargas, Jonathan; Feng, Yang; Dimitrov, Dimiter S; Jones, David R; Sadelain, Michel; Adusumilli, Prasad S

    2016-08-01

    Following immune attack, solid tumors upregulate coinhibitory ligands that bind to inhibitory receptors on T cells. This adaptive resistance compromises the efficacy of chimeric antigen receptor (CAR) T cell therapies, which redirect T cells to solid tumors. Here, we investigated whether programmed death-1-mediated (PD-1-mediated) T cell exhaustion affects mesothelin-targeted CAR T cells and explored cell-intrinsic strategies to overcome inhibition of CAR T cells. Using an orthotopic mouse model of pleural mesothelioma, we determined that relatively high doses of both CD28- and 4-1BB-based second-generation CAR T cells achieved tumor eradication. CAR-mediated CD28 and 4-1BB costimulation resulted in similar levels of T cell persistence in animals treated with low T cell doses; however, PD-1 upregulation within the tumor microenvironment inhibited T cell function. At lower doses, 4-1BB CAR T cells retained their cytotoxic and cytokine secretion functions longer than CD28 CAR T cells. The prolonged function of 4-1BB CAR T cells correlated with improved survival. PD-1/PD-1 ligand [PD-L1] pathway interference, through PD-1 antibody checkpoint blockade, cell-intrinsic PD-1 shRNA blockade, or a PD-1 dominant negative receptor, restored the effector function of CD28 CAR T cells. These findings provide mechanistic insights into human CAR T cell exhaustion in solid tumors and suggest that PD-1/PD-L1 blockade may be an effective strategy for improving the potency of CAR T cell therapies. PMID:27454297

  11. Aptamer-mediated indirect quantum dot labeling and fluorescent imaging of target proteins in living cells

    International Nuclear Information System (INIS)

    Protein labeling for dynamic living cell imaging plays a significant role in basic biological research, as well as in clinical diagnostics and therapeutics. We have developed a novel strategy in which the dynamic visualization of proteins within living cells is achieved by using aptamers as mediators for indirect protein labeling of quantum dots (QDs). With this strategy, the target protein angiogenin was successfully labeled with fluorescent QDs in a minor intactness model, which was mediated by the aptamer AL6-B. Subsequent living cell imaging analyses indicated that the QDs nanoprobes were selectively bound to human umbilical vein endothelial cells, gradually internalized into the cytoplasm, and mostly localized in the lysosome organelle, indicating that the labeled protein retained high activity. Compared with traditional direct protein labeling methods, the proposed aptamer-mediated strategy is simple, inexpensive, and provides a highly selective, stable, and intact labeling platform that has shown great promise for future biomedical labeling and intracellular protein dynamic analyses. (paper)

  12. The Biological Effects of IL-21 Signaling on B-Cell-Mediated Responses in Organ Transplantation

    Science.gov (United States)

    Wu, Yongkang; van Besouw, Nicole M.; Shi, Yunying; Hoogduijn, Martin J.; Wang, Lanlan; Baan, Carla C.

    2016-01-01

    Antibody-mediated rejection has emerged as one of the major issues limiting the success of organ transplantation. It exerts a highly negative impact on graft function and outcome, and effective treatment is lacking. The triggers for antibody development, and the mechanisms leading to graft dysfunction and failure, are incompletely understood. The production of antibodies is dependent on instructions from various immunocytes including CD4 T-helper cells that secrete interleukin (IL)-21 and interact with antigen-specific B-cells via costimulatory molecules. In this article, we discuss the role of IL-21 in the activation and differentiation of B-cells and consider the mechanisms of IL-21 and B-cell interaction. An improved understanding of the biological mechanisms involved in antibody-mediated complications after organ transplantation could lead to the development of novel therapeutic strategies, which control humoral alloreactivity, potentially preventing and treating graft-threatening antibody-mediated rejection. PMID:27602031

  13. The Biological Effects of IL-21 Signaling on B-Cell-Mediated Responses in Organ Transplantation.

    Science.gov (United States)

    Wu, Yongkang; van Besouw, Nicole M; Shi, Yunying; Hoogduijn, Martin J; Wang, Lanlan; Baan, Carla C

    2016-01-01

    Antibody-mediated rejection has emerged as one of the major issues limiting the success of organ transplantation. It exerts a highly negative impact on graft function and outcome, and effective treatment is lacking. The triggers for antibody development, and the mechanisms leading to graft dysfunction and failure, are incompletely understood. The production of antibodies is dependent on instructions from various immunocytes including CD4 T-helper cells that secrete interleukin (IL)-21 and interact with antigen-specific B-cells via costimulatory molecules. In this article, we discuss the role of IL-21 in the activation and differentiation of B-cells and consider the mechanisms of IL-21 and B-cell interaction. An improved understanding of the biological mechanisms involved in antibody-mediated complications after organ transplantation could lead to the development of novel therapeutic strategies, which control humoral alloreactivity, potentially preventing and treating graft-threatening antibody-mediated rejection. PMID:27602031

  14. Polycystin-1 promotes PKCα-mediated NF-κB activation in kidney cells

    International Nuclear Information System (INIS)

    Polycystin-1 (PC1), the PKD1 gene product, is a membrane receptor which regulates many cell functions, including cell proliferation and apoptosis, both typically increased in cyst lining cells in autosomal dominant polycystic kidney disease. Here we show that PC1 upregulates the NF-κB signalling pathway in kidney cells to prevent cell death. Human embryonic kidney cell lines (HEK293CTT), stably expressing a PC1 cytoplasmic terminal tail (CTT), presented increased NF-κB nuclear levels and NF-κB-mediated luciferase promoter activity. This, consistently, was reduced in HEK293 cells in which the endogenous PC1 was depleted by RNA interference. CTT-dependent NF-κB promoter activation was mediated by PKCα because it was blocked by its specific inhibitor Ro-320432. Furthermore, it was observed that apoptosis, which was increased in PC1-depleted cells, was reduced in HEK293CTT cells and in porcine kidney LtTA cells expressing a doxycycline-regulated CTT. Staurosporine, a PKC inhibitor, and parthenolide, a NF-κB inhibitor, significantly reduced the CTT-dependent antiapoptotic effect. These data reveal, therefore, a novel pathway by which polycystin-1 activates a PKCα-mediated NF-κB signalling and cell survival

  15. The 3 major types of innate and adaptive cell-mediated effector immunity.

    Science.gov (United States)

    Annunziato, Francesco; Romagnani, Chiara; Romagnani, Sergio

    2015-03-01

    The immune system has tailored its effector functions to optimally respond to distinct species of microbes. Based on emerging knowledge on the different effector T-cell and innate lymphoid cell (ILC) lineages, it is clear that the innate and adaptive immune systems converge into 3 major kinds of cell-mediated effector immunity, which we propose to categorize as type 1, type 2, and type 3. Type 1 immunity consists of T-bet(+) IFN-γ-producing group 1 ILCs (ILC1 and natural killer cells), CD8(+) cytotoxic T cells (TC1), and CD4(+) TH1 cells, which protect against intracellular microbes through activation of mononuclear phagocytes. Type 2 immunity consists of GATA-3(+) ILC2s, TC2 cells, and TH2 cells producing IL-4, IL-5, and IL-13, which induce mast cell, basophil, and eosinophil activation, as well as IgE antibody production, thus protecting against helminthes and venoms. Type 3 immunity is mediated by retinoic acid-related orphan receptor γt(+) ILC3s, TC17 cells, and TH17 cells producing IL-17, IL-22, or both, which activate mononuclear phagocytes but also recruit neutrophils and induce epithelial antimicrobial responses, thus protecting against extracellular bacteria and fungi. On the other hand, type 1 and 3 immunity mediate autoimmune diseases, whereas type 2 responses can cause allergic diseases. PMID:25528359

  16. Glycosylation inhibitors efficiently inhibit P-selectin-mediated cell adhesion to endothelial cells.

    Science.gov (United States)

    Ghoshal, Pushpankur; Rajendran, Mythilypriya; Odo, Nadine; Ikuta, Tohru

    2014-01-01

    Adhesion molecules play a critical role in the adhesive interactions of multiple cell types in sickle cell disease (SCD). We previously showed that anti-P-selectin aptamer efficiently inhibits cell adhesion to endothelial cells (ECs) and permits SCD mice to survive hypoxic stress. In an effort to discover new mechanisms with which to inhibit P-selectin, we examined the role of glycosylation. P-selectin is a 90 kDa protein but was found to migrate as 90 and 140 kDa bands on gel electrophoresis. When P-selectin isolated from ECs was digested with peptide N-glycosidase F, but not O-glycosidase, the 140 kDa band was lost and the 90 kDa band was enhanced. Treatment of ECs with tunicamycin, an N-glycosylation inhibitor, suppressed CD62P (P-selectin) expression on the cell surface as well as the 140 kDa form in the cytoplasm. These results indicate that the 140 kDa band is N-glycosylated and glycosylation is critical for cell surface expression of P-selectin in ECs. Thrombin, which stimulates P-selectin expression on ECs, induced AKT phosphorylation, whereas tunicamycin inhibited AKT phosphorylation, suggesting that AKT signaling is involved in the tunicamycin-mediated inhibition of P-selectin expression. Importantly, the adhesion of sickle red blood cells (sRBCs) and leukocytes to ECs induced by thrombin or hypoxia was markedly inhibited by two structurally distinct glycosylation inhibitors; the levels of which were comparable to that of a P-selectin monoclonal antibody which most strongly inhibited cell adhesion in vivo. Knockdown studies of P-selectin using short-hairpin RNAs in ECs suppressed sRBC adhesion, indicating a legitimate role for P-selectin in sRBC adhesion. Together, these results demonstrate that P-selectin expression on ECs is regulated in part by glycosylation mechanisms and that glycosylation inhibitors efficiently reduce the adhesion of sRBCs and leukocytes to ECs. Glycosylation inhibitors may lead to a novel therapy which inhibits cell adhesion in SCD.

  17. B cells mediate chronic allograft rejection independently of antibody production.

    Science.gov (United States)

    Zeng, Qiang; Ng, Yue-Harn; Singh, Tripti; Jiang, Ke; Sheriff, Khaleefathullah A; Ippolito, Renee; Zahalka, Salwa; Li, Qi; Randhawa, Parmjeet; Hoffman, Rosemary A; Ramaswami, Balathiripurasundari; Lund, Frances E; Chalasani, Geetha

    2014-03-01

    Chronic rejection is the primary cause of long-term failure of transplanted organs and is often viewed as an antibody-dependent process. Chronic rejection, however, is also observed in mice and humans with no detectable circulating alloantibodies, suggesting that antibody-independent pathways may also contribute to pathogenesis of transplant rejection. Here, we have provided direct evidence that chronic rejection of vascularized heart allografts occurs in the complete absence of antibodies, but requires the presence of B cells. Mice that were deficient for antibodies but not B cells experienced the same chronic allograft vasculopathy (CAV), which is a pathognomonic feature of chronic rejection, as WT mice; however, mice that were deficient for both B cells and antibodies were protected from CAV. B cells contributed to CAV by supporting splenic lymphoid architecture, T cell cytokine production, and infiltration of T cells into graft vessels. In chimeric mice, in which B cells were present but could not present antigen, both T cell responses and CAV were markedly reduced. These findings establish that chronic rejection can occur in the complete absence of antibodies and that B cells contribute to this process by supporting T cell responses through antigen presentation and maintenance of lymphoid architecture.

  18. B cells mediate chronic allograft rejection independently of antibody production.

    Science.gov (United States)

    Zeng, Qiang; Ng, Yue-Harn; Singh, Tripti; Jiang, Ke; Sheriff, Khaleefathullah A; Ippolito, Renee; Zahalka, Salwa; Li, Qi; Randhawa, Parmjeet; Hoffman, Rosemary A; Ramaswami, Balathiripurasundari; Lund, Frances E; Chalasani, Geetha

    2014-03-01

    Chronic rejection is the primary cause of long-term failure of transplanted organs and is often viewed as an antibody-dependent process. Chronic rejection, however, is also observed in mice and humans with no detectable circulating alloantibodies, suggesting that antibody-independent pathways may also contribute to pathogenesis of transplant rejection. Here, we have provided direct evidence that chronic rejection of vascularized heart allografts occurs in the complete absence of antibodies, but requires the presence of B cells. Mice that were deficient for antibodies but not B cells experienced the same chronic allograft vasculopathy (CAV), which is a pathognomonic feature of chronic rejection, as WT mice; however, mice that were deficient for both B cells and antibodies were protected from CAV. B cells contributed to CAV by supporting splenic lymphoid architecture, T cell cytokine production, and infiltration of T cells into graft vessels. In chimeric mice, in which B cells were present but could not present antigen, both T cell responses and CAV were markedly reduced. These findings establish that chronic rejection can occur in the complete absence of antibodies and that B cells contribute to this process by supporting T cell responses through antigen presentation and maintenance of lymphoid architecture. PMID:24509079

  19. RAD18 mediates resistance to ionizing radiation in human glioma cells

    Energy Technology Data Exchange (ETDEWEB)

    Xie, Chen; Wang, Hongwei; Cheng, Hongbin; Li, Jianhua; Wang, Zhi, E-mail: drzwang@gmail.com; Yue, Wu, E-mail: drwuyue@gmail.com

    2014-02-28

    Highlights: • RAD18 is an important mediator of the IR-induced resistance in glioma cell lines. • RAD18 overexpression confers resistance to IR-mediated apoptosis. • The elevated expression of RAD18 is associated with recurrent GBM who underwent IR therapy. - Abstract: Radioresistance remains a major challenge in the treatment of glioblastoma multiforme (GBM). RAD18 a central regulator of translesion DNA synthesis (TLS), has been shown to play an important role in regulating genomic stability and DNA damage response. In the present study, we investigate the relationship between RAD18 and resistance to ionizing radiation (IR) and examined the expression levels of RAD18 in primary and recurrent GBM specimens. Our results showed that RAD18 is an important mediator of the IR-induced resistance in GBM. The expression level of RAD18 in glioma cells correlates with their resistance to IR. Ectopic expression of RAD18 in RAD18-low A172 glioma cells confers significant resistance to IR treatment. Conversely, depletion of endogenous RAD18 in RAD18-high glioma cells sensitized these cells to IR treatment. Moreover, RAD18 overexpression confers resistance to IR-mediated apoptosis in RAD18-low A172 glioma cells, whereas cells deficient in RAD18 exhibit increased apoptosis induced by IR. Furthermore, knockdown of RAD18 in RAD18-high glioma cells disrupts HR-mediated repair, resulting in increased accumulation of DSB. In addition, clinical data indicated that RAD18 was significantly higher in recurrent GBM samples that were exposed to IR compared with the corresponding primary GBM samples. Collectively, our findings reveal that RAD18 may serve as a key mediator of the IR response and may function as a potential target for circumventing IR resistance in human GBM.

  20. Betamethasone, but Not Tacrolimus, Suppresses the Development of Th2 Cells Mediated by Langerhans Cell-Like Dendritic Cells.

    Science.gov (United States)

    Matsui, Katsuhiko; Tamai, Saki; Ikeda, Reiko

    2016-01-01

    It is well known that Langerhans cells (LCs) work as the primary orchestrators in the polarization of the immune milieu towards a T helper type 1 (Th1) or T helper type 2 (Th2) response. In this study, we investigated the effects of tacrolimus and betamethasone, each used as topical applications in atopic dermatitis (AD), on Th2 cell development mediated by LCs. LC-like dendritic cells (LDCs) were generated from mouse bone marrow cells and used as substitutes for LCs. Mice were primed with ovalbumin (OVA) peptide-pulsed LDCs, which had been treated with tacrolimus or betamethasone, via the hind footpad. After 5 d, the cytokine response in the popliteal lymph nodes was investigated by enzyme-linked immunosorbent assay. The expression of cell surface molecules on LDCs was investigated via reverse transcriptase polymerase chain reaction. Administration of OVA peptide-pulsed LDCs, which had been treated with betamethasone, inhibited Th2 cell development, as represented by the down-regulation of interleukin-4 production, and also inhibited Th1 cell development, represented by the down-regulation of interferon-γ production. However, tacrolimus-treated LDCs did not induce such inhibition of the development of Th1 and Th2 cells. The inhibition of Th1 and Th2 cell development was associated with the suppression of CD40 and T-cell immunoglobulin, and mucin domain-containing protein (TIM)-4 expression, respectively, in LDCs. These results suggest that the topical application of betamethasone to skin lesions of patients with AD acts on epidermal LCs, and may inhibit the development of Th2 cells, thus being of benefit for the control of AD. PMID:27374298

  1. Cell-cell contact and anatomical compatibility in stromal cell-mediated HSC support during development

    NARCIS (Netherlands)

    K. Harvey (Kirsten); E.A. Dzierzak (Elaine)

    2004-01-01

    textabstractHematopoietic stem cells (HSCs) are able to generate the wide variety of blood cells found in the adult and are maintained in the bone marrow (BM) stromal microenvironment. In the aorta-gonads-mesonephros (AGM), which autonomously generates the first HSCs, the stromal m

  2. Mechanisms of KGF mediated signaling in pancreatic duct cell proliferation and differentiation.

    Directory of Open Access Journals (Sweden)

    Benjamin Uzan

    Full Text Available BACKGROUND: Keratinocyte growth factor (KGF; palifermin is a growth factor with a high degree of specificity for epithelial cells. KGF is an important effector of epithelial growth and tissue homeostasis in various organs including the pancreas. Here we investigated the intracellular signaling pathways involved in the mediation of pancreatic ductal cell proliferation and differentiation induced by exogenous KGF during beta-cell regeneration in diabetic rat. METHODOLOGY AND RESULTS: In vitro and in vivo duct cell proliferation was measured by BrdU incorporation assay. The implication of MAPK-ERK1/2 in the mediation of KGF-induced cell proliferation was determined by inactivation of this pathway, using the pharmacological inhibitor or antisense morpholino-oligonucleotides against MEK1. In vivo KGF-induced duct cell differentiation was assessed by the immunolocalization of PDX1 and Glut2 in ductal cells and the implication of PI3K/AKT in this process was investigated. We showed that KGF exerted a potent mitogenic effect on ductal cells. Both in vitro and in vivo, its effect on cell proliferation was mediated through the activation of ERK1/2 as evidenced by the abolition of duct cell proliferation in the context of MEK/ERK inactivation. In vivo, KGF treatment triggered ductal cell differentiation as revealed by the expression of PDX1 and Glut2 in a subpopulation of ductal cells via a PI3K-dependent mechanism. CONCLUSION: Here we show that KGF promotes beta-cell regeneration by stimulating duct cell proliferation in vivo. Moreover, we demonstrated for the first time that KGF directly induces the expression of PDX1 in some ductal cells thus inducing beta-cell neogenesis. We further explored the molecular mechanisms involved in these processes and showed that the effects of KGF on duct cell proliferation are mediated by the MEK-ERK1/2 pathway, while the KGF-induced cell differentiation is mediated by the PI3K/AKT pathway. These findings might have

  3. Mediation of autophagic cell death by type 3 ryanodine receptor (RyR3 in adult hippocampal neural stem cells

    Directory of Open Access Journals (Sweden)

    Kyung Min eChung

    2016-05-01

    Full Text Available Cytoplasmic Ca2+ actively engages in diverse intracellular processes from protein synthesis, folding and trafficking to cell survival and death. Dysregulation of intracellular Ca2+ levels is observed in various neuropathological states including Alzheimer’s and Parkinson’s diseases. Ryanodine receptors (RyRs and IP3 receptors (IP3Rs, the main Ca2+ release channels located in endoplasmic reticulum (ER membranes, are known to direct various cellular events such as autophagy and apoptosis. Here we investigated the intracellular Ca2+-mediated regulation of survival and death of adult hippocampal neural stem (HCN cells utilizing an insulin withdrawal model of autophagic cell death. Despite comparable expression levels of RyR and IP3R transcripts in HCN cells at normal state, the expression levels of RyRs — especially RyR3 — were markedly upregulated upon insulin withdrawal. While treatment with the RyR agonist caffeine significantly promoted the autophagic death of insulin-deficient HCN cells, treatment with its inhibitor dantrolene prevented the induction of autophagy following insulin withdrawal. Furthermore, CRISPR/Cas9-mediated knockout of the RyR3 gene abolished autophagic cell death of HCN cells. This study delineates a distinct, RyR3-mediated ER Ca2+ regulation of autophagy and programmed cell death in neural stem cells. Our findings provide novel insights into the critical, yet understudied mechanisms underlying the regulatory function of ER Ca2+ in neural stem cell biology.

  4. Identifying Intracellular Sites of Eicosanoid Lipid Mediator Synthesis with EicosaCell Assays

    OpenAIRE

    Bandeira-Melo, Christianne; Weller, Peter Fahey; Bozza, Patricia T.

    2011-01-01

    Eicosanoids, arachidonic acid-derived signaling lipid mediators, are newly formed and nonstorable molecules that have important roles in physiological and pathological processes. EicosaCell is a microscopic assay that enables the intracellular detection and localization of eicosanoid lipid mediator-synthesizing compartments by means of a strategy to covalently cross-link and immobilize eicosanoids at their sites of synthesis followed by immunofluorescent-based localization of the targeted eic...

  5. Targeted microbubbles for ultrasound mediated gene transfection and apoptosis induction in ovarian cancer cells

    OpenAIRE

    Chang, Shufang; Guo, Juan; Sun, Jiangchuan; Zhu, Shenyin; Yan, Yu; Zhu, Yi; Li, Min; Wang, Zhigang; Xu, Ronald X

    2012-01-01

    Ultrasound-targeted microbubble destruction (UTMD) technique can be potentially used for non-viral delivery of gene therapy. Targeting wild-type p53 (wtp53) tumor suppressor gene may provide a clinically promising treatment for patients with ovarian cancer. However, UTMD mediated gene therapy typically uses non-targeted microbubbles with suboptimal gene transfection efficiency. We synthesized a targeted microbubble agent for UTMD mediated wtp53 gene therapy in ovarian cancer cells. Lipid micr...

  6. IL-35-mediated induction of a potent regulatory T cell population.

    Science.gov (United States)

    Collison, Lauren W; Chaturvedi, Vandana; Henderson, Abigail L; Giacomin, Paul R; Guy, Cliff; Bankoti, Jaishree; Finkelstein, David; Forbes, Karen; Workman, Creg J; Brown, Scott A; Rehg, Jerold E; Jones, Michael L; Ni, Hsiao-Tzu; Artis, David; Turk, Mary Jo; Vignali, Dario A A

    2010-12-01

    Regulatory T cells (T(reg) cells) have a critical role in the maintenance of immunological self-tolerance. Here we show that treatment of naive human or mouse T cells with IL-35 induced a regulatory population, which we call 'iT(R)35 cells', that mediated suppression via IL-35 but not via the inhibitory cytokines IL-10 or transforming growth factor-β (TGF-β). We found that iT(R)35 cells did not express or require the transcription factor Foxp3, and were strongly suppressive and stable in vivo. T(reg) cells induced the generation of iT(R)35 cells in an IL-35- and IL-10-dependent manner in vitro and induced their generation in vivo under inflammatory conditions in intestines infected with Trichuris muris and within the tumor microenvironment (B16 melanoma and MC38 colorectal adenocarcinoma), where they contributed to the regulatory milieu. Thus, iT(R)35 cells constitute a key mediator of infectious tolerance and contribute to T(reg) cell-mediated tumor progression. Furthermore, iT(R)35 cells generated ex vivo might have therapeutic utility.

  7. Function of Helper T Cells in the Memory CTL-mediated Anti-tumor Immunity

    Institute of Scientific and Technical Information of China (English)

    高丰光; GermainJ.P.Fernendo; 刘文军

    2004-01-01

    Abstract To investigate the role of CD4+ helper T (Th) cells in the memory CTL-mediated anti-tumor immunity, the RAG-1 gene knock out mice were adoptively transferred with OT-1 cells to generate the memory CTL, the C57B1/6 mice immunized with the epitope peptide of OVA specific Th cells and with different adjuvants were adopfively transferred with these memory-CTLs, and then the animals were challenged with tumor cells EGT. It was found that although the simple immunization of mice with the epitope peptide of the OVA specific Th cells could generate more effect CTL, but this effect was not so strong enough to resist completely the challenges with tumor cells. Nevertheless, the memory CTL-mediated anti-tumor immune effect required the helps of Th1 and Th2 cells. The cross-regulation between Thl and Th2 cells seemed to be beneficial for the host to generate more effector CTL for mounting an efficient anti-tumor response. It concluded that the interaction between Thl and Th2 cells might be more important than the single subset of Th cells in the memory CTL-mediated anti-tumor immune response. More attention should be paid in this regard for the future studies.

  8. Role of the spleen in cell-mediated cardiac allograft rejection

    Energy Technology Data Exchange (ETDEWEB)

    Hall, B.M.

    1982-04-01

    A quantitative adoptive transfer assay was used to investigate the role of the spleen in cell-mediated rejection of directly vascularized heart grafts. In this assay, the cell-mediated rejection response can be examined directly by testing the capacity of inocula of T cells to effect rejection of DA heart grafts in PVG rats whose own lymphocytes have been destroyed by whole body irradiation. The capacity of a variety of inocula, including lymph node cells (LNCs), spleen cells, and T cells from lymph node and spleen, to restore rejection were compared in groups of splenectomized and nonsplenectomized hosts. In both groups all inocula restored rejection toward normal. Only in experiments testing inocula equivalent to a small fraction of the naive peripheral lymphocyte pool was rejection delayed in the splenectomized hosts, and this was only a delay of a few days. These results showed that in the absence of the spleen, the primary rejection responses can be generated. In addition, it was demonstrated that the normal spleen contains only a small fraction of the T cell pool with the capacity to effect rejection. Memory T cells were also shown to mediate rejection in splenectomized hosts. It is concluded that with strongly incompatible grafts, splenectomy has only a trivial immunosuppressive effect; it removes neither a sigificant proportion of the alloreactive T cell pool nor the essential site for activation of proliferation of these cells.

  9. A unified theory for systems and cellular memory consolidation.

    Science.gov (United States)

    Dash, Pramod K; Hebert, April E; Runyan, Jason D

    2004-04-01

    The time-limited role of the hippocampus for explicit memory storage has been referred to as systems consolidation where learning-related changes occur first in the hippocampus followed by the gradual development of a more distributed memory trace in the neocortex. Recent experiments are beginning to show that learning induces plasticity-related molecular changes in the neocortex as well as in the hippocampus and with a similar time course. Present memory consolidation theories do not account for these findings. In this report, we present a theory (the C theory) that incorporates these new findings, provides an explanation for the length of time for hippocampal dependency, and that can account for the apparent longer consolidation periods in species with larger brains. This theory proposes that a process of cellular consolidation occurs in the hippocampus and in areas of the neocortex during and shortly after learning resulting in long-term memory storage in both areas. For a limited time, the hippocampus is necessary for memory retrieval, a process involving the coordinated reactivation of these areas. This reactivation is later mediated by longer extrahippocampal connectivity between areas. The delay in hippocampal-independent memory retrieval is the time it takes for gene products in these longer extrahippocampal projections to be transported from the soma to tagged synapses by slow axonal transport. This cellular transport event defines the period of hippocampal dependency and, thus, the duration of memory consolidation. The theoretical description for memory consolidation presented in this review provides alternative explanations for several experimental observations and presents a unification of the concepts of systems and cellular memory consolidation.

  10. Macrophage-Mediated Trogocytosis Leads to Death of Antibody-Opsonized Tumor Cells.

    Science.gov (United States)

    Velmurugan, Ramraj; Challa, Dilip K; Ram, Sripad; Ober, Raimund J; Ward, E Sally

    2016-08-01

    Understanding the complex behavior of effector cells such as monocytes or macrophages in regulating cancerous growth is of central importance for cancer immunotherapy. Earlier studies using CD20-specific antibodies have demonstrated that the Fcγ receptor (FcγR)-mediated transfer of the targeted receptors from tumor cells to these effector cells through trogocytosis can enable escape from antibody therapy, leading to the viewpoint that this process is protumorigenic. In the current study, we demonstrate that persistent trogocytic attack results in the killing of HER2-overexpressing breast cancer cells. Further, antibody engineering to increase FcγR interactions enhances this tumoricidal activity. These studies extend the complex repertoire of activities of macrophages to trogocytic-mediated cell death of HER2-overexpressing target cells and have implications for the development of effective antibody-based therapies. Mol Cancer Ther; 15(8); 1879-89. ©2016 AACR. PMID:27226489

  11. CDK8-Mediated STAT1-S727 Phosphorylation Restrains NK Cell Cytotoxicity and Tumor Surveillance

    Directory of Open Access Journals (Sweden)

    Eva Maria Putz

    2013-08-01

    Full Text Available The transcription factor STAT1 is important in natural killer (NK cells, which provide immediate defense against tumor and virally infected cells. We show that mutation of a single phosphorylation site (Stat1-S727A enhances NK cell cytotoxicity against a range of tumor cells, accompanied by increased expression of perforin and granzyme B. Stat1-S727A mice display significantly delayed disease onset in NK cell-surveilled tumor models including melanoma, leukemia, and metastasizing breast cancer. Constitutive phosphorylation of S727 depends on cyclin-dependent kinase 8 (CDK8. Inhibition of CDK8-mediated STAT1-S727 phosphorylation may thus represent a therapeutic strategy for stimulating NK cell-mediated tumor surveillance.

  12. Bone marrow stromal cell : mediated neuroprotection for spinal cord repair

    NARCIS (Netherlands)

    Ritfeld, Gaby Jane

    2014-01-01

    Currently, there is no treatment available that restores anatomy and function after spinal cord injury. This thesis explores transplantation of bone marrow-derived mesenchymal stem cells (bone marrow stromal cells; BMSCs) as a therapeutic approach for spinal cord repair. BMSCs secrete neurotrophic f

  13. Suppression by Apoptotic Cells Defines Tumor Necrosis Factor-Mediated Induction of Glomerular Mesangial Cell Apoptosis by Activated Macrophages

    OpenAIRE

    Duffield, Jeremy S.; Ware, Carl F.; Ryffel, Bernhardt; Savill, John

    2001-01-01

    Activated macrophages (Mφ) isolated from inflamed glomeruli or generated by interferon-γ and lipopolysaccharide treatment in vitro induce glomerular mesangial cell apoptosis by hitherto incompletely understood mechanisms. In this report we demonstrate that nitric oxide-independent killing of co-cultured mesangial cells by interferon-γ/lipopolysaccharide-activated Mφ is suppressed by binding/ingestion of apoptotic cells and is mediated by tumor necrosis factor (TNF). Thus, soluble TNF receptor...

  14. Lysosome fusion to the cell membrane is mediated by the dysferlin C2A domain in coronary arterial endothelial cells

    OpenAIRE

    Han, Wei-Qing; Xia, Min; Xu, Ming; Krishna M Boini; Ritter, Joseph K.; Li, Ning-Jun; Li, Pin-Lan

    2012-01-01

    Dysferlin has recently been reported to participate in cell membrane repair in muscle and other cells through lysosome fusion. Given that lysosome fusion is a crucial mechanism that leads to membrane raft clustering, the present study attempted to determine whether dysferlin is involved in this process and its related signalling, and explores the mechanism underlying dysferlin-mediated lysosome fusion in bovine coronary arterial endothelial cells (CAECs). We found that dysferlin is clustered ...

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

    Science.gov (United States)

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

    2016-09-01

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

  16. Retrovirus-Mediated Gene Transfer in Immortalization of Progenitor Hair Cell Lines in Newborn Rat

    Institute of Scientific and Technical Information of China (English)

    ZHANG Yuan; ZHAI Suo-qiang; SONG Wei; GUO Wei; ZHENG Gui-liang; HU Yin-yan

    2008-01-01

    Objective To present an experimental method that allows isolation of greater epithelial ridge (GER) and lesser epithelial ridge(LER) cells from postnatal rat cochleae using a combinatorial approach of enzymatic digestion and mechanical separation and to investigate a retrovirus-mediated gene transfer technique for its possibl utility in immortalization of the GER and LER cell lines, in an effort to establish an in vitro model system of hair cell differentiation. Methods GER and LER cells were dissected from postnatal rat cochleae and immortalized by transferring the SV40 large T antigen using a retrovirus. The established cell lines were confirmed through morphology observation, immunnocytochemical staining and RT-PCR analysis. The Hathl gene was transferred into the cell lines using adenovirus-mediated techniques to explore their potential to differentiate into hair cells. Results The established cell lines were stably maintained for more than 20 passages and displayed many features similar to primary GER and LER cells. They grew in patches and assumed a polygonal morphology. Immunostaining showed labeling by SV40 large T antigen and Islet1 (a specific marker for GER and LER). All passages of the cell lines expressed SV40 large T antigen on RT-PCR analysis. The cells also showed the capability to differenti-ate into hair cell-like cells when forced to express Hathl. Conclusion Retrovirus-mediated gene transfer can be used in establishing immortalized progenitor hair cell lines in newborn rat, which may provide an invaluable system for studying hair cell differentiation and regeneration for new treatment of sensory hearing loss caused by hair cell loss.

  17. Mannose 6-, fructose 1-, and fructose 6-phosphates inhibit human natural cell-mediated cytotoxicity.

    OpenAIRE

    Forbes, J T; Bretthauer, R. K.; Oeltmann, T N

    1981-01-01

    In vitro human natural cell-mediated cytotoxicity (NCMC) to K-562, Molt-4, and F-265 cells is inhibited in a dose-dependent manner by mannose 6-phosphate, fructose 1-phosphate and fructose 6-phosphate. This inhibition is not observed with mannose, glucose, fucose, glucose 6-phosphate, mannose 1-phosphate, galactose 1-phosphate, or galactose 6-phosphate. Preincubation of the effector cells, obtained from fresh whole blood, with mannose-6-phosphate, fructose-1-phosphate, or fructose-6-phosphate...

  18. Pokemon Silencing Leads to Bim-Mediated Anoikis of Human Hepatoma Cell QGY7703

    OpenAIRE

    Kun Liu; Feng Liu(Central China Normal University); Nannan Zhang; Shiying Liu; Yuyang Jiang

    2012-01-01

    Pokemon is an important proto-oncogene that plays a critical role in cellular oncogenic transformation and tumorigenesis. Anoikis, which is regulated by Bim-mediated apoptosis, is critical to cancer cell invasion and metastasis. We investigated the role of Pokemon in anoikis, and our results show that Pokemon renders liver cells resistant to anoikis via suppression of Bim transcription. We knocked-down Pokemon in human hepatoma cells QGY7703 with small interfering RNAs (siRNA). Knockdown of P...

  19. Status of rod consolidation, 1988

    International Nuclear Information System (INIS)

    It is estimated that the spent fuel storage pools at some domestic light-water reactors will run out of space before 2003, the year that the US Department of Energy currently predicts it will have a repository available. Of the methods being studied to alleviate the problem, rod consolidation is one of the leading candidates for achieving more efficient use of existing space in spent fuel storage pools. Rod consolidation involves mechanically removing all the fuel rods from the fuel assembly hardware (i.e., the structural components) and placing the fuel rods in a close-packed array in a canister without space grids. A typical goal of rod consolidation systems is to insert the fuel rods from two fuel assemblies into a canister that has the same exterior dimensions as one standard fuel assembly (i.e., to achieve a consolidation or compaction ratio of 2:1) and to compact the nonfuel-bearing structural components from those two fuel assemblies by a factor of 10 to 20. This report provides an overview of the current status of rod consolidation in the United States and a small amount of information on related activities in other countries. 85 refs., 36 figs., 5 tabs

  20. High glucose-mediated oxidative stress impairs cell migration.

    Directory of Open Access Journals (Sweden)

    Marcelo L Lamers

    Full Text Available Deficient wound healing in diabetic patients is very frequent, but the cellular and molecular causes are poorly defined. In this study, we evaluate the hypothesis that high glucose concentrations inhibit cell migration. Using CHO.K1 cells, NIH-3T3 fibroblasts, mouse embryonic fibroblasts and primary skin fibroblasts from control and diabetic rats cultured in 5 mM D-glucose (low glucose, LG, 25 mM D-glucose (high glucose, HG or 25 mM L-glucose medium (osmotic control--OC, we analyzed the migration speed, protrusion stability, cell polarity, adhesion maturation and the activity of the small Rho GTPase Rac1. We also analyzed the effects of reactive oxygen species by incubating cells with the antioxidant N-Acetyl-Cysteine (NAC. We observed that HG conditions inhibited cell migration when compared to LG or OC. This inhibition resulted from impaired cell polarity, protrusion destabilization and inhibition of adhesion maturation. Conversely, Rac1 activity, which promotes protrusion and blocks adhesion maturation, was increased in HG conditions, thus providing a mechanistic basis for the HG phenotype. Most of the HG effects were partially or completely rescued by treatment with NAC. These findings demonstrate that HG impairs cell migration due to an increase in oxidative stress that causes polarity loss, deficient adhesion and protrusion. These alterations arise, in large part, from increased Rac1 activity and may contribute to the poor wound healing observed in diabetic patients.

  1. Slit2 involvement in glioma cell migration is mediated by Robo1 receptor.

    Science.gov (United States)

    Mertsch, Sonja; Schmitz, Nicole; Jeibmann, Astrid; Geng, Jian-Guo; Paulus, Werner; Senner, Volker

    2008-03-01

    Slit and Robo proteins are evolutionarily conserved molecules whose interaction underlies axon guidance and neuronal precursor cell migration. During development secreted Slit proteins mediate chemorepulsive signals on cells expressing Robo receptors. Because similar molecular mechanisms may be utilized in glioma cell invasion and neuroblast migration, we studied the expression of Slit2 and its transmembrane receptor Robo1 as well as their functional role in migration in glioma cells. qRT-PCR and immunohistochemistry of human specimens revealed that Slit2 was distinctly expressed by non-neoplastic neurons, but at only very low levels in fibrillary astrocytoma and glioblastoma. Robo1 also was mainly restricted to neurons in the normal brain, whereas astrocytic tumor cells in situ as well as glioblastoma cell lines overexpressed Robo1 at mRNA and protein levels. Recombinant human Slit2 in a concentration of 0.45 nM was repulsive for glioma cell lines in a modified Boyden chamber assay. RNAi-mediated knockdown of Robo1 in glioma cell lines neutralized the repulsive effect of Slit2, demonstrating that Robo1 served as the major Slit2 receptor. Our findings suggest that a chemorepulsive effect mediated by interaction of Slit2 and Robo1 participates in glioma cell guidance in the brain.

  2. Effect of disodium cromoglycate on mast cell-mediated immediate-type allergic reactions.

    Science.gov (United States)

    Shin, Hye-Young; Kim, Jung-Sook; An, Nyeon-Hyoung; Park, Rae-Kil; Kim, Hyung-Min

    2004-04-23

    We investigated the effect of disodium cromoglycate (DSCG) on mast cell-mediated immediate-type hypersensitivity. DSCG inhibited systemic allergic reaction induced by compound 48/80 dose-dependently. Passive cutaneous anaphylaxis was inhibited by 71.6% by oral administration of DSCG (1 g/kg). When DSCG was pretreated at concentration rang from 0.01-1000 g/kg, the serum histamine levels were reduced in a dose dependent manner. DSCG also significantly inhibited histamine release from rat peritoneal mast cell (RPMC) by compound 48/80. We confirmed that DSCG inhibited compound 48/80-induced degranulation of RPMC by alcian blue/nuclear fast red staining. In addition, DSCG showed a significant inhibitory effect on anti-dinitrophenyl IgE-mediated tumor necrosis factor-alpha production. These results indicate that DSCG inhibits mast cell-mediated immediate-type allergic reaction. PMID:15050425

  3. Memory Consolidation and Neural Substrate of Reward

    Directory of Open Access Journals (Sweden)

    Redolar-Ripoll, Diego

    2012-08-01

    Full Text Available The aim of this report is to analyze the relationships between reward and learning and memory processes. Different studies have described how information about rewards influences behavior and how the brain uses this reward information to control learning and memory processes. Reward nature seems to be processed in different ways by neurons in different brain structures, ranging from the detection and perception of rewards to the use of information about predicted rewards for the control of goal-directed behavior. The neural substrate underling this processing of reward information is a reliable way of improving learning and memory processes. Evidence from several studies indicates that this neural system can facilitate memory consolidation in a wide variety of learning tasks. From a molecular perspective, certain cardinal features of reward have been described as forms of memory. Studies of human addicts and studies in animal models of addiction show that chronic drug exposure produces stable changes in the brain at the cellular and molecular levels that underlie the long-lasting behavioral plasticity associated with addiction. These molecular and cellular adaptations involved in addiction are also implicated in learning and memory processes. Dopamine seems to be a critical common signal to activate different genetic mechanisms that ultimately remodel synapses and circuits. Despite memory is an active and complex process mediated by different brain areas, the neural substrate of reward is able to improve memory consolidation in a several paradigms. We believe that there are many equivalent traits between reward and learning and memory processes.

  4. Bax translocation mediated mitochondrial apoptosis and caspase dependent photosensitizing effect of Ficus religiosa on cancer cells.

    Directory of Open Access Journals (Sweden)

    Jazir Haneef

    Full Text Available The main aim of the present work was to investigate the potential effect of acetone extract of Ficus religosa leaf (FAE in multiple apoptosis signalling in human breast cancer cells. FAE treatment significantly induced dose and time dependent, irreversible inhibition of breast cancer cell growth with moderate toxicity to normal breast epithelial cells. This observation was validated using Sulforhodamine B assay. Cell cycle analysis by Flow cytometry showed cell cycle arrest in G1 phase and induction of sub-G0 peak. FAE induced chromatin condensation and displayed an increase in apoptotic population in Annexin V-FITC/PI (Fluorescein isothiocyanate/Propidium iodide double staining. FAE stimulated the loss of mitochondrial membrane potential in multiple breast cancer cell lines when compared to normal diploid cells. To understand the role of Bax in FAE induced apoptosis, we employed a sensitive cell based platform of MCF-7 cells expressing Bax-EGFP. Bax translocation to mitochondria was accompanied by the disruption of mitochondrial membrane potential and marked elevation in LEHDase activity (Caspase 9. Consistent with this data, FAE induced Caspase activation as evidenced by ratio change in FRET Caspase sensor expressing MCF-7 cell line and cleavage of prominent Caspases and PARP. Interestingly, FAE accelerated cell death in a mitochondrial dependent manner in continuous live cell imaging mode indicating its possible photosensitizing effect. Intracellular generation of reactive oxygen species (ROS by FAE played a critical role in mediating apoptotic cell death and photosensitizing activity. FAE induced dose and time dependent inhibition of cancer cell growth which was associated with Bax translocation and mitochondria mediated apoptosis with the activation of Caspase 9 dependent Caspase cascade. FAE also possessed strong photosensitizing effect on cancer cell line that was mediated through rapid mitochondrial transmembrane potential loss and

  5. Bax translocation mediated mitochondrial apoptosis and caspase dependent photosensitizing effect of Ficus religiosa on cancer cells.

    Science.gov (United States)

    Haneef, Jazir; Parvathy, Muraleedharan; M, Parvathy; Thankayyan R, Santhosh Kumar; Sithul, Hima; Sreeharshan, Sreeja

    2012-01-01

    The main aim of the present work was to investigate the potential effect of acetone extract of Ficus religosa leaf (FAE) in multiple apoptosis signalling in human breast cancer cells. FAE treatment significantly induced dose and time dependent, irreversible inhibition of breast cancer cell growth with moderate toxicity to normal breast epithelial cells. This observation was validated using Sulforhodamine B assay. Cell cycle analysis by Flow cytometry showed cell cycle arrest in G1 phase and induction of sub-G0 peak. FAE induced chromatin condensation and displayed an increase in apoptotic population in Annexin V-FITC/PI (Fluorescein isothiocyanate/Propidium iodide) double staining. FAE stimulated the loss of mitochondrial membrane potential in multiple breast cancer cell lines when compared to normal diploid cells. To understand the role of Bax in FAE induced apoptosis, we employed a sensitive cell based platform of MCF-7 cells expressing Bax-EGFP. Bax translocation to mitochondria was accompanied by the disruption of mitochondrial membrane potential and marked elevation in LEHDase activity (Caspase 9). Consistent with this data, FAE induced Caspase activation as evidenced by ratio change in FRET Caspase sensor expressing MCF-7 cell line and cleavage of prominent Caspases and PARP. Interestingly, FAE accelerated cell death in a mitochondrial dependent manner in continuous live cell imaging mode indicating its possible photosensitizing effect. Intracellular generation of reactive oxygen species (ROS) by FAE played a critical role in mediating apoptotic cell death and photosensitizing activity. FAE induced dose and time dependent inhibition of cancer cell growth which was associated with Bax translocation and mitochondria mediated apoptosis with the activation of Caspase 9 dependent Caspase cascade. FAE also possessed strong photosensitizing effect on cancer cell line that was mediated through rapid mitochondrial transmembrane potential loss and partial Caspase

  6. Cutting edge: membrane lymphotoxin regulates CD8(+) T cell-mediated intestinal allograft rejection.

    Science.gov (United States)

    Guo, Z; Wang, J; Meng, L; Wu, Q; Kim, O; Hart, J; He, G; Zhou, P; Thistlethwaite, J R; Alegre, M L; Fu, Y X; Newell, K A

    2001-11-01

    Blocking the CD28/B7 and/or CD154/CD40 costimulatory pathways promotes long-term allograft survival in many transplant models where CD4(+) T cells are necessary for rejection. When CD8(+) T cells are sufficient to mediate rejection, these approaches fail, resulting in costimulation blockade-resistant rejection. To address this problem we examined the role of lymphotoxin-related molecules in CD8(+) T cell-mediated rejection of murine intestinal allografts. Targeting membrane lymphotoxin by means of a fusion protein, mAb, or genetic mutation inhibited rejection of intestinal allografts by CD8(+) T cells. This effect was associated with decreased monokine induced by IFN-gamma (Mig) and secondary lymphoid chemokine (SLC) gene expression within allografts and spleens respectively. Blocking membrane lymphotoxin did not inhibit rejection mediated by CD4(+) T cells. Combining disruption of membrane lymphotoxin and treatment with CTLA4-Ig inhibited rejection in wild-type mice. These data demonstrate that membrane lymphotoxin is an important regulatory molecule for CD8(+) T cells mediating rejection and suggest a strategy to avoid costimulation blockade-resistant rejection. PMID:11673481

  7. HLA-G inhibits xenogenetic cytotoxicity mediated by human NK cells and T lymphocytes against PECs

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    In order to investigate whether the non-classi-cal HLA-G classⅠmolecule protects the porcine endothelial cells (PECs) from the lysis mediated by human immune cells in pig to human discordant xenotransplantation, we have cloned HLA-G cDNA from a human placenta by RT-PCR. Mammalian expression vector, pEFG-neo, was constructed by insertion of HLA-G cDNA in pEF-neo. We obtained efficiently expressed PECs by stable transfection. Cytotoxicity assay showed that overexpression of HLA-G on PECs was sufficient to inhibit human NK-92 cell lysis. The level of lysis was equal to or less than that of the lysis of human umbilical vein endothelial cells mediated by human NK-92 cells. It also indicated that HLA-G inhibited the lysis of PECs mediated by xeno-antigen specific T lymphocytes. The reduction of lysis ranged between 59.1% and 88.9%. These findings suggest that the transgenic approach to overexpress HLA-G is believed to be a new immunotherapy in overcoming the immune rejections in xenotransplantion, including delayed xenograft rejection and cell-mediated rejection.

  8. Towards Future T Cell-Mediated Influenza Vaccines

    Directory of Open Access Journals (Sweden)

    Thi H. O. Nguyen

    2016-04-01

    Full Text Available Influenza A virus (IAVs infections impact significantly on global health, being particularly problematic in children, the elderly, pregnant women, indigenous populations and people with co-morbidities. Antibody-based vaccines require annual administration to combat rapidly acquired mutations modifying the surface haemagglutinin (HA and neuraminidase (NA glycoproteins. Conversely, influenza-specific CD8+ T cell responses directed at peptides derived from the more conserved internal virus proteins are known to be protective, suggesting that T cell-based vaccines may provide long-lasting cross-protection. This review outlines the importance of CD8+ T cell immunity to seasonal influenza and pandemic IAVs and summarises current vaccination strategies for inducing durable CD8+ T cell memory. Aspects of future IAV vaccine design and the use of live virus challenge in humans to establish proof of principle are also discussed.

  9. Control of Th2-Mediated Inflammation by Regulatory T Cells

    OpenAIRE

    Poojary, K. Venuprasad; Kong, Yi-chi M.; Farrar, Michael A.

    2010-01-01

    Allergic diseases and asthma are caused by dysregulated Th2-type immune responses, which drive disease development in susceptible individuals. Immune tolerance to allergens prevents inflammatory symptoms in the respiratory mucosa and provides protection against inflammation in the airways. Increasing evidence indicates that Foxp3+ regulatory T cells (Tregs) play a critical role in immune tolerance and control Th2-biased responses. Tregs develop in the thymus from CD4+ T cells (natural Tregs) ...

  10. Specific Btk inhibition suppresses B cell- and myeloid cell-mediated arthritis

    Energy Technology Data Exchange (ETDEWEB)

    Di Paolo, Julie A; Huang, Tao; Balazs, Mercedesz; Barbosa, James; Barck, Kai H; Bravo, Brandon J; Carano, Richard A.D.; Darrow, James; Davies, Douglas R; DeForge, Laura E; Diehl, Lauri; Ferrando, Ronald; Gallion, Steven L; Giannetti, Anthony M; Gribling, Peter; Hurez, Vincent; Hymowitz, Sarah G; Jones, Randall; Kropf, Jeffrey E; Lee, Wyne P; Maciejewski, Patricia M; Mitchell, Scott A; Rong, Hong; Staker, Bart L; Whitney, J Andrew; Yeh, Sherry; Young, Wendy B; Yu, Christine; Zhang, Juan; Reif, Karin; Currie, Kevin S [CGI; (Emerald); (Genentech)

    2011-08-29

    Bruton's tyrosine kinase (Btk) is a therapeutic target for rheumatoid arthritis, but the cellular and molecular mechanisms by which Btk mediates inflammation are poorly understood. Here we describe the discovery of CGI1746, a small-molecule Btk inhibitor chemotype with a new binding mode that stabilizes an inactive nonphosphorylated enzyme conformation. CGI1746 has exquisite selectivity for Btk and inhibits both auto- and transphosphorylation steps necessary for enzyme activation. Using CGI1746, we demonstrate that Btk regulates inflammatory arthritis by two distinct mechanisms. CGI1746 blocks B cell receptor–dependent B cell proliferation and in prophylactic regimens reduces autoantibody levels in collagen-induced arthritis. In macrophages, Btk inhibition abolishes FcγRIII-induced TNFα, IL-1β and IL-6 production. Accordingly, in myeloid- and FcγR-dependent autoantibody-induced arthritis, CGI1746 decreases cytokine levels within joints and ameliorates disease. These results provide new understanding of the function of Btk in both B cell– or myeloid cell–driven disease processes and provide a compelling rationale for targeting Btk in rheumatoid arthritis.

  11. Heat-preconditioning confers protection from Ca2+-mediated cell toxicity in renal tubular epithelial cells (BSC-1)

    OpenAIRE

    Kuhlmann, Martin K.; Betz, Regina; Hanselmann, Rainer; Köhler, Hans

    1997-01-01

    A rise in intracellular calcium may mediate ischemic damage by phospholipid hydrolysis and proteolysis Heat shock proteins have been shown to provide protection from various forms of cell stress, but not from models of Ca2+-mediated injury. The effect of heat preconditioning in a model of ionomycin-induced injury in cultured renal tubular epitheliaal cells (BSC-1) was examined. Hsp70-mRNA expression was induced by hyperthermia (HT) (42°C, 60 min). Hsp70 protein accumulation was maximal after ...

  12. The Role of TG2 in Regulating S100A4-Mediated Mammary Tumour Cell Migration

    OpenAIRE

    Zhuo Wang; Martin Griffin

    2013-01-01

    The importance of S100A4, a Ca(2+)-binding protein, in mediating tumour cell migration, both intracellularly and extracellularly, is well documented. Tissue transglutaminase (TG2) a Ca(2+)-dependent protein crosslinking enzyme, has also been shown to enhance cell migration. Here by using the well characterised non-metastatic rat mammary R37 cells (transfected with empty vector) and highly metastatic KP1 cells (R37 cells transfected with S100A4), we demonstrate that inhibition of TG2 either by...

  13. Redox Imbalance in T Cell-Mediated Skin Diseases

    Directory of Open Access Journals (Sweden)

    Saveria Pastore

    2010-01-01

    Full Text Available The skin is permanently exposed to physical, chemical, and biological aggression by the environment. In addition, acute and chronic inflammatory events taking place in the skin are accompanied by abnormal release of pro-oxidative mediators. In this paper, we will briefly overview the homeostatic systems active in the skin to maintain the redox balance and also to counteract abnormal oxidative stress. We will concentrate on the evidence that a local and/or systemic redox dysregulation accompanies the chronic inflammatory disorder events associated to psoriasis, contact dermatitis, and atopic dermatitis. We will also discuss the fact that several well-established treatments for the therapy of chronic inflammatory skin disorders are based on the application of strong physical or chemical oxidants onto the skin, indicating that, in selected conditions, a further increase of the oxidative imbalance may lead to a beneficial outcome.

  14. Cutting edge: TNFR-shedding by CD4+CD25+ regulatory T cells inhibits the induction of inflammatory mediators.

    NARCIS (Netherlands)

    Mierlo, G.J. van; Scherer, H.U.; Hameetman, M.; Morgan, M.E.; Flierman, R.; Huizinga, T.W.J.; Toes, R.E.

    2008-01-01

    CD4+CD25+ regulatory T (Treg) cells play an essential role in maintaining tolerance to self and nonself. In several models of T cell-mediated (auto) immunity, Treg cells exert protective effects by the inhibition of pathogenic T cell responses. In addition, Treg cells can modulate T cell-independent

  15. The double-edge role of B cells in mediating antitumor T-cell immunity: Pharmacological strategies for cancer immunotherapy.

    Science.gov (United States)

    Wang, Jing-Zhang; Zhang, Yu-Hua; Guo, Xin-Hua; Zhang, Hong-Yan; Zhang, Yuan

    2016-07-01

    Emerging evidence reveals the controversial role of B cells in antitumor immunity, but the underlying mechanisms have to be explored. Three latest articles published in the issue 521 of Nature in 2015 reconfirmed the puzzling topic and put forward some explanations of how B cells regulate antitumor T-cell responses both positively and negatively. This paper attempts to demonstrate that different B-cell subpopulations have distinct immunological properties and that they are involved in either antitumor responses or immunosuppression. Recent studies supporting the positive and negative roles of B cells in tumor development were summarized comprehensively. Several specific B-cell subpopulations, such as IgG(+), IgA(+), IL-10(+), and regulatory B cells, were described in detail. The mechanisms underlying the controversial B-cell effects were mainly attributed to different B-cell subpopulations, different B-cell-derived cytokines, direct B cell-T cell interaction, different cancer categories, and different malignant stages, and the immunological interaction between B cells and T cells is mediated by dendritic cells. Promising B-cell-based antitumor strategies were proposed and novel B-cell regulators were summarized to present interesting therapeutic targets. Future investigations are needed to make sure that B-cell-based pharmacological strategies benefit cancer immunotherapy substantially.

  16. Analysis of cell-mediated immune responses in support of dengue vaccine development efforts.

    Science.gov (United States)

    Rothman, Alan L; Currier, Jeffrey R; Friberg, Heather L; Mathew, Anuja

    2015-12-10

    Dengue vaccine development has made significant strides, but a better understanding of how vaccine-induced immune responses correlate with vaccine efficacy can greatly accelerate development, testing, and deployment as well as ameliorate potential risks and safety concerns. Advances in basic immunology knowledge and techniques have already improved our understanding of cell-mediated immunity of natural dengue virus infection and vaccination. We conclude that the evidence base is adequate to argue for inclusion of assessments of cell-mediated immunity as part of clinical trials of dengue vaccines, although further research to identify useful correlates of protective immunity is needed.

  17. P-Selectin-Mediated Platelet Adhesion Promotes the Metastasis of Murine Melanoma Cells

    OpenAIRE

    Cui-Ling Qi; Bo Wei; Jie Ye; Yang Yang; Bin Li; Qian-Qian Zhang; Jiang-Chao Li; Xiao-Dong He; Tian Lan; Li-Jing Wang

    2014-01-01

    Studies have indicated that the aggregation of activated platelets with cancer cells facilitates tumor metastasis; the adhesion molecule P-selectin may be an important mediator of this process, but the detailed mechanism is unclear. In the current study, we established a B16F10 (B16) cell metastatic model in P-selectin knockout (P-sel-/-) mice to determine the effect of P-selectin-mediated platelet adhesion on metastasis. Compared with C57 mice, P-sel-/- mice developed fewer metastatic foci, ...

  18. Electron Transfer Mediators for Photoelectrochemical Cells Based on Cu(I Metal Complexes

    Directory of Open Access Journals (Sweden)

    Michele Brugnati

    2007-01-01

    Full Text Available The preparation and the photoelectrochemical characterization of a series of bipyridine and pyridyl-quinoline Cu(I complexes, used as electron transfer mediators in regenerative photoelectrochemical cells, are reported. The best performing mediators produced maximum IPCEs of the order of 35–40%. The J-V curves recorded under monochromatic light showed that the selected Cu(I/(II couples generated higher Vocs and fill factors compared to an equivalent I-/I3- cell, due to a decreased dark current.

  19. Alpha-synuclein promotes clathrin-mediated endocytosis of NMDA receptors in dopaminergic cells

    Institute of Scientific and Technical Information of China (English)

    Shun Yu; Furong Cheng; Xin Li; Yaohua Li; Tao Wang; Guangwei Liu; Andrius Baskys

    2012-01-01

    Loss of dopaminergic i a compensatory increase in nput to the striatum associated with Parkinson' s disease brings about glutamate release onto the dopaminergic cell bodies in the substantia nigra pars compacta (SNpc)[1] Glutamate over-activation of NMDA receptors on these cells can cause excitotoxicity and contribute to their further loss. NMDA receptor-mediated neuronal death is reduced by group I mGluR-mediated up-regulation of endocytosis protein RAB5B[2.3] Among proteins shown to interact with RAB5 proteins is a-synuclein

  20. Glucocorticoid receptor-mediated induction of glutamine synthetase in skeletal muscle cells in vitro

    Science.gov (United States)

    Max, Stephen R.; Thomas, John W.; Banner, Carl; Vitkovic, Ljubisa; Konagaya, Masaaki

    1987-01-01

    The regulation by glucocorticoids of glutamine synthetase in L6 muscle cells in culture is studied. Glutamine synthetase activity was strikingly enhanced by dexamethasone. The dexamethasone-mediated induction of glutamine synthetase activity was blocked by RU38486, a glucocorticoid antagonist, indicating the involvement of intracellular glucocorticoid receptors in the induction process. RU38486 alone was without effect. Northern blot analysis revealed that dexamethasone-mediated enhancement of glutamine synthetase activity involves increased levels of glutamine synthetase mRNA. Glucocorticoids regulate the expression of glutamine synthetase mRNA in cultured muscle cells via interaction with intracellular receptors. Such regulation may be relevant to control of glutamine production by muscle.

  1. Immunotherapy: Shifting the Balance of Cell-Mediated Immunity and Suppression in Human Prostate Cancer

    Directory of Open Access Journals (Sweden)

    Jeffrey Schlom

    2012-12-01

    Full Text Available Active immunotherapy is dependent on the ability of the immune system to recognize and respond to tumors. Despite overwhelming evidence to support a cell-mediated immune response to prostate cancer, it is insufficient to eradicate the disease. This is likely due to a high level of suppression at the tumor site from a variety of sources, including immunosuppressive cells. Immune cells entering the tumor microenvironment may be inhibited directly by the tumor, stromal cells or other immune cells that have been induced to adopt a suppressive phenotype. The resurgence of interest in immunotherapy following the approval of sipuleucel-T and ipilimumab by the Food and Drug Administration has brought about new strategies for overcoming tumor-mediated suppression and bolstering anti-tumor responses. Improved understanding of the immune response to prostate cancer can lead to new combination therapies, such as the use of vaccine with small molecule and checkpoint inhibitors or other immunotherapies.

  2. Immunotherapy: Shifting the Balance of Cell-Mediated Immunity and Suppression in Human Prostate Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Tucker, Jo A.; Jochems, Caroline [Laboratory of Tumor Immunology and Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892 (United States); Gulley, James L. [Laboratory of Tumor Immunology and Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892 (United States); Medical Oncology Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892 (United States); Schlom, Jeffrey, E-mail: js141c@nih.gov; Tsang, Kwong Y. [Laboratory of Tumor Immunology and Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892 (United States)

    2012-12-11

    Active immunotherapy is dependent on the ability of the immune system to recognize and respond to tumors. Despite overwhelming evidence to support a cell-mediated immune response to prostate cancer, it is insufficient to eradicate the disease. This is likely due to a high level of suppression at the tumor site from a variety of sources, including immunosuppressive cells. Immune cells entering the tumor microenvironment may be inhibited directly by the tumor, stromal cells or other immune cells that have been induced to adopt a suppressive phenotype. The resurgence of interest in immunotherapy following the approval of sipuleucel-T and ipilimumab by the Food and Drug Administration has brought about new strategies for overcoming tumor-mediated suppression and bolstering anti-tumor responses. Improved understanding of the immune response to prostate cancer can lead to new combination therapies, such as the use of vaccine with small molecule and checkpoint inhibitors or other immunotherapies.

  3. Immunotherapy: Shifting the Balance of Cell-Mediated Immunity and Suppression in Human Prostate Cancer

    International Nuclear Information System (INIS)

    Active immunotherapy is dependent on the ability of the immune system to recognize and respond to tumors. Despite overwhelming evidence to support a cell-mediated immune response to prostate cancer, it is insufficient to eradicate the disease. This is likely due to a high level of suppression at the tumor site from a variety of sources, including immunosuppressive cells. Immune cells entering the tumor microenvironment may be inhibited directly by the tumor, stromal cells or other immune cells that have been induced to adopt a suppressive phenotype. The resurgence of interest in immunotherapy following the approval of sipuleucel-T and ipilimumab by the Food and Drug Administration has brought about new strategies for overcoming tumor-mediated suppression and bolstering anti-tumor responses. Improved understanding of the immune response to prostate cancer can lead to new combination therapies, such as the use of vaccine with small molecule and checkpoint inhibitors or other immunotherapies

  4. The role of TG2 in regulating S100A4-mediated mammary tumour cell migration.

    Directory of Open Access Journals (Sweden)

    Zhuo Wang

    Full Text Available The importance of S100A4, a Ca(2+-binding protein, in mediating tumour cell migration, both intracellularly and extracellularly, is well documented. Tissue transglutaminase (TG2 a Ca(2+-dependent protein crosslinking enzyme, has also been shown to enhance cell migration. Here by using the well characterised non-metastatic rat mammary R37 cells (transfected with empty vector and highly metastatic KP1 cells (R37 cells transfected with S100A4, we demonstrate that inhibition of TG2 either by TG2 inhibitors or transfection of cells with TG2 shRNA block S100A4-accelerated cell migration in the KP1cells and in R37 cells treated with exogenous S100A4. Cell migration was also blocked by the treatment with the non-cell permeabilizing TG2 inhibitor R294, in the human breast cancer cell line MDA-MB-231 (Clone 16, which has a high level of TG2 expression. Inhibition was paralleled by a decrease in S100A4 polymer formation. In vitro co-immunoprecipitation and Far Western blotting assays and cross-linking assays showed not only the direct interaction between TG2 and S100A4, but also confirmed S100A4 as a substrate for TG2. Using specific functional blocking antibodies, a targeting peptide and a recombinant protein as a competitive treatment, we revealed the involvement of syndecan-4 and α5β1 integrin co-signalling pathways linked by activation of PKCα in this TG2 and S100A4-mediated cell migration. We propose a mechanism for TG2-regulated S100A4-related mediated cell migration, which is dependent on TG2 crosslinking.

  5. Lovastatin-Mediated Changes in Human Tendon Cells.

    Science.gov (United States)

    Kuzma-Kuzniarska, Maria; Cornell, Hannah R; Moneke, Michael C; Carr, Andrew J; Hulley, Philippa A

    2015-10-01

    Statins are among the most widely prescribed drugs worldwide. Numerous studies have shown their beneficial effects in prevention of cardiovascular disease through cholesterol-lowering and anti-atherosclerotic properties. Although some statin patients may experience muscle-related symptoms, severe side effects of statin therapy are rare, primarily due to extensive first-pass metabolism in the liver. Skeletal muscles appear to be the main site of side effects; however, recently some statin-related adverse effects have been described in tendon. The mechanism behind these side effects remains unknown. This is the first study that explores tendon-specific effects of statins in human primary tenocytes. The cells were cultured with different concentrations of lovastatin for up to 1 week. No changes in cell viability or morphology were observed in tenocytes incubated with therapeutic doses. Short-term exposure to lovastatin concentrations outside the therapeutic range had no effect on tenocyte viability; however, cell migration was reduced. Simvastatin and atorvastatin, two other drug family members, also reduced the migratory properties of the cells. Prolonged exposure to high concentrations of lovastatin induced changes in cytoskeleton leading to cell rounding and decreased levels of mRNA for matrix proteins, but increased BMP-2 expression. Gap junctional communication was impaired but due to cell shape change and separation rather than direct gap junction inhibition. These effects were accompanied by inhibition of prenylation of Rap1a small GTPase. Collectively, we showed that statins in a dose-dependent manner decrease migration of human tendon cells, alter their expression profile and impair the functional network, but do not inhibit gap junction function.

  6. AspC-mediated aspartate metabolism coordinates the Escherichia coli cell cycle.

    Directory of Open Access Journals (Sweden)

    Feng Liu

    Full Text Available The fast-growing bacterial cell cycle consists of at least two independent cycles of chromosome replication and cell division. To ensure proper cell cycles and viability, chromosome replication and cell division must be coordinated. It has been suggested that metabolism could affect the Escherichia coli cell cycle, but the idea is still lacking solid evidences.We found that absence of AspC, an aminotransferase that catalyzes synthesis of aspartate, led to generation of small cells with less origins and slow growth. In contrast, excess AspC was found to exert the opposite effect. Further analysis showed that AspC-mediated aspartate metabolism had a specific effect in the cell cycle, as only extra aspartate of the 20 amino acids triggered production of bigger cells with more origins per cell and faster growth. The amount of DnaA protein per cell was found to be changed in response to the availability of AspC. Depletion of (pppGpp by ΔrelAΔspoT led to a slight delay in initiation of replication, but did not change the replication pattern found in the ΔaspC mutant.The results suggest that AspC-mediated metabolism of aspartate coordinates the E. coli cell cycle through altering the amount of the initiator protein DnaA per cell and the division signal UDP-glucose. Furthermore, AspC sequence conservation suggests similar functions in other organisms.

  7. Comparison of lentiviral and sleeping beauty mediated αβ T cell receptor gene transfer.

    Directory of Open Access Journals (Sweden)

    Anne-Christine Field

    Full Text Available Transfer of tumour antigen-specific receptors to T cells requires efficient delivery and integration of transgenes, and currently most clinical studies are using gamma retroviral or lentiviral systems. Whilst important proof-of-principle data has been generated for both chimeric antigen receptors and αβ T cell receptors, the current platforms are costly, time-consuming and relatively inflexible. Alternative, more cost-effective, Sleeping Beauty transposon-based plasmid systems could offer a pathway to accelerated clinical testing of a more diverse repertoire of recombinant high affinity T cell receptors. Nucleofection of hyperactive SB100X transposase-mediated stable transposition of an optimised murine-human chimeric T cell receptor specific for Wilm's tumour antigen from a Sleeping Beauty transposon plasmid. Whilst transfer efficiency was lower than that mediated by lentiviral transduction, cells could be readily enriched and expanded, and mediated effective target cells lysis in vitro and in vivo. Integration sites of transposed TCR genes in primary T cells were almost randomly distributed, contrasting the predilection of lentiviral vectors for transcriptionally active sites. The results support exploitation of the Sleeping Beauty plasmid based system as a flexible and adaptable platform for accelerated, early-phase assessment of T cell receptor gene therapies.

  8. NK cell-mediated killing of AML blasts. Role of histamine, monocytes and reactive oxygen metabolites

    International Nuclear Information System (INIS)

    Blasts recovered from patients with acute myelogenous leukaemia (AML) were lysed by heterologeous natural killer (NK) cells treated with NK cell-activating cytokine-induced killing of AML blasts was inhibited by monocytes, recovered from peripheral blood by counterflow centrifugal elutriation. Histamine, at concentrations exceeding 0.1 μM, abrogated the monocyte-induced inhibition of NK cells; thereby, histamine and IL-2 or histamine and IFN-α synergistically induced NK cell-mediated destruction of AML blasts. The effect of histamine was completely blocked by the histamine H2-receptor (H2R) antagonist ranitidine but not by its chemical control AH20399AA. Catalase, a scavenger of reactive oxygen metabolites (ROM), reversed the monocyte-induced inhibition of NK cell-mediated killing of blast cells, indicating that the inhibitory signal was mediated by products of the respiratory burst of monocytes. It is concluded that (i) monocytes inhibit anti-leukemic properties of NK cells, (ii) the inhibition is conveyed by monocyte-derived ROM, and (iii) histamine reverses the inhibitory signal and, thereby, synergizes with NK cell-activating cytokines to induce killing of AML blasts. (au) 19 refs

  9. Conceptual Design for Consolidation TCAP

    International Nuclear Information System (INIS)

    Two alternate Thermal Cycling Absorption Process (TCAP) designs have been developed for the Tritium Facility Modernization and Consolidation (TFM and C) Project. The alternate designs were developed to improve upon the existing Replacement Tritium Facility (RTF) TCAP design and to eliminate the use of building distributed hot and cold nitrogen system.A brief description of TCAP theory and modeling is presented, followed by an overview of the design criteria for the Isotope Separation System (ISS). Both designs are described in detail, along with a generic description of the complete TCAP system. A design is recommend for the Consolidation Project, and a development plan for both designs is proposed

  10. Thermodynamics of the nanoparticle consolidation

    Directory of Open Access Journals (Sweden)

    Lisovsky A.F.

    2009-01-01

    Full Text Available Thermodynamic functions have been derived that describe the processes of nanoparticle consolidation in solid-mobile phase two- and three-phase dispersed systems. An expression for the shrinkage pressure in a two-phase dispersed system has been deduced, which allows one to calculate stresses generating in the bulk of heterophase composite materials in the course of the nanoparticle consolidation. On the strength of these thermodynamic functions criteria have been suggested that allow one to predict the structure of a nanocomposite material.

  11. HIV-1 Nef enhances dendritic cell-mediated viral transmission to CD4+ T cells and promotes T-cell activation.

    Directory of Open Access Journals (Sweden)

    Corine St Gelais

    Full Text Available HIV-1 Nef enhances dendritic cell (DC-mediated viral transmission to CD4(+ T cells, but the underlying mechanism is not fully understood. It is also unknown whether HIV-1 infected DCs play a role in activating CD4(+ T cells and enhancing DC-mediated viral transmission. Here we investigated the role of HIV-1 Nef in DC-mediated viral transmission and HIV-1 infection of primary CD4(+ T cells using wild-type HIV-1 and Nef-mutated viruses. We show that HIV-1 Nef facilitated DC-mediated viral transmission to activated CD4(+ T cells. HIV-1 expressing wild-type Nef enhanced the activation and proliferation of primary resting CD4(+ T cells. However, when co-cultured with HIV-1-infected autologous DCs, there was no significant trend for infection- or Nef-dependent proliferation of resting CD4(+ T cells. Our results suggest an important role of Nef in DC-mediated transmission of HIV-1 to activated CD4(+ T cells and in the activation and proliferation of resting CD4(+ T cells, which likely contribute to viral pathogenesis.

  12. Bone morphogenetic protein 4 mediates human embryonic germ cell derivation.

    Science.gov (United States)

    Hiller, Marc; Liu, Cyndi; Blumenthal, Paul D; Gearhart, John D; Kerr, Candace L

    2011-02-01

    Human primordial germ cells (PGCs) have proven to be a source of pluripotent stem cells called embryonic germ cells (EGCs). Unlike embryonic stem cells, virtually little is known regarding the factors that regulate EGC survival and maintenance. In mice, the growth factor bone morphogenetic protein 4 (BMP4) has been shown to be required for maintaining mouse embryonic stem cells, and disruptions in this gene lead to defects in mouse PGC specification. Here, we sought to determine whether recombinant human BMP4 could influence EGC derivation and/or human PGC survival. We found that the addition of recombinant BMP4 increased the number of human PGCs after 1 week of culture in a dose-responsive manner. The efficiency of EGC derivation and maintenance in culture was also enhanced by the presence of recombinant BMP4 based on alkaline phosphatase and OCT4 staining. In addition, an antagonist of the BMP4 pathway, Noggin, decreased PGC proliferation and led to an increase in cystic embryoid body formation. Quantitative real-time (qRT)-polymerase chain reaction analyses and immunostaining confirmed that the constituents of the BMP4 pathway were upregulated in EGCs versus PGCs. Downstream activators of the BMP4 pathway such as ID1 and phosphorylated SMADs 1 and 5 were also expressed, suggesting a role of this growth factor in EGC pluripotency. PMID:20486775

  13. Melatonin-mediated cytoprotection against hyperglycemic injury in Muller cells.

    Directory of Open Access Journals (Sweden)

    Tingting Jiang

    Full Text Available Oxidative stress is a contributing factor to the development and progression of diabetic retinopathy, a leading cause of blindness in people at working age worldwide. Recent studies showed that Müller cells play key roles in diabetic retinopathy and produce vascular endothelial growth factor (VEGF that regulates retinal vascular leakage and proliferation. Melatonin is a potent antioxidant capable of protecting variety of retinal cells from oxidative damage. In addition to the pineal gland, the retina produces melatonin. In the current study, we investigated whether melatonin protects against hyperglycemia-induced oxidative injury to Müller cells and explored the potential underlying mechanisms. Our results show that both melatonin membrane receptors, MT1 and MT2, are expressed in cultured primary Müller cells and are upregulated by elevated glucose levels. Both basal and high glucose-induced VEGF production was attenuated by melatonin treatment in a dose-dependent manner. Furthermore, we found that melatonin is a potent activator of Akt in Müller cells. Our findings suggest that in addition to functioning as a direct free radical scavenger, melatonin can elicit cellular signaling pathways that are protective against retinal injury during diabetic retinopathy.

  14. Building Cell Selectivity into CPP-Mediated Strategies

    Directory of Open Access Journals (Sweden)

    Irene Martín

    2010-05-01

    Full Text Available There is a pressing need for more effective and selective therapies for cancer and other diseases. Consequently, much effort is being devoted to the development of alternative experimental approaches based on selective systems, which are designed to be specifically directed against target cells. In addition, a large number of highly potent therapeutic molecules are being discovered. However, they do not reach clinical trials because of their low delivery, poor specificity or their incapacity to bypass the plasma membrane. Cell-penetrating peptides (CPPs are an open door for cell-impermeable compounds to reach intracellular targets. Putting all these together, research is sailing in the direction of the design of systems with the capacity to transport new drugs into a target cell. Some CPPs show cell type specificity while others require modifications or form part of more sophisticated drug delivery systems. In this review article we summarize several strategies for directed drug delivery involving CPPs that have been reported in the literature.

  15. NF-KB downregulation may be involved the depression of tumor cell proliferation mediated by human mesenchymal stem cells

    Institute of Scientific and Technical Information of China (English)

    Ling QIAO; Tie-jun ZHAO; Feng-ze WANG; Chang-liang SHAN; Li-hong YE; Xiao-dong ZHANG

    2008-01-01

    Aim:It has been reported that stem cells are able to home to tumorigenesis and inhibit the proliferation of tumor cells.The purpose of our study was to demon-strate the molecular mechanism of the inhibitory proliferation of hepatoma cells and breast cancer cells mediated by human mesenchymal stem cells (hMSCs).Methods:The proliferation of H7402 human hepatoma cells and MCF-7 human breast cancer cells was measured by the 5-bromodeoxyuridine (BrdU) incorpora-tion assay and flow cytometry assay after the treatment with conditioned media from hMSCs culture,such as Z3 cells or BMMS-03 cells.The role of NF-kB or the phosphorylation of inhibitor kBoα (p-IkBα) in the depression of hepatoma or breast cancer cells treated with conditioned media from Z3 cells or BMMS-03 cells was examined by reporter gene assay,quantitative real-time PCR,and Western blot analysis,respectively.Results:The proliferation of H7402 cells and MCF-7 cells was decreased significantly by the BrdU incorporation assay and flow cytometry assay after treatment.The transcriptional activity and mRNA level of NF-kB were downregulated in the treated cells by reporter gene assay and quantitative real-time PCR in a dose-dependent manner.At the protein level,NF-kB and p-IkBα decreased in the treated cells by Western blot analysis.Conclusion:Conditioned media from hMSCs are able to inhibit the proliferation of tumor cells.NF-kB downregulation is one of reasons for the depression of tumor cell proliferation mediated by hMSCs.

  16. ROS accumulation by PEITC selectively kills ovarian cancer cells via UPR-mediated apoptosis

    Directory of Open Access Journals (Sweden)

    Yoon-hee eHong

    2015-07-01

    Full Text Available Unfolded protein response (UPR is crucial for both survival and death of mammalian cells, which is regulated by reactive oxygen species (ROS and nutrient depletion. In this study, we demonstrated the effect of ROS-accumulation, induced by β-phenethyl isothiocyanate (PEITC, on UPR mediated apoptosis in ovarian cancer cells. We used ovarian cancer cell lines, PA-1 and SKOV-3, with different p53 status (wild- and null- type, respectively. PEITC caused increased ROS-accumulation and inhibited proliferation selectively in ovarian cancer cells, and glutathione (GSH depletion in SKOV-3. However, PEITC did not cause any effect in normal ovarian epithelial cells and peripheral blood mononuclear cells. After 48 h of PEITC treatment (5 µM, apoptotic cell death was shown to increase significantly in the ovarian cancer cells and not in the normal cells. The key regulator of UPR-mediated apoptosis, CHOP/GADD153 and ER resident chaperone BiP/GRP78 were parallely up-regulated with activation of two major sensors of the UPR (PERK and ATF-6 in PA-1; PERK, and IRE1α in SKOV-3 in response to ROS accumulation induced by PEITC (5 µM. ROS scavenger, N-acetyl-cysteine (NAC, attenuated the effect of PEITC on UPR signatures (P-PERK, IRE1α, CHOP/GADD153, and BiP/GRP78, suggesting the involvement of ROS in UPR-mediated apoptosis. Altogether, PEITC induces UPR-mediated apoptosis in ovarian cancer cells via accumulation of ROS in a cancer-specific manner.

  17. ZFAT plays critical roles in peripheral T cell homeostasis and its T cell receptor-mediated response

    Energy Technology Data Exchange (ETDEWEB)

    Doi, Keiko [Department of Cell Biology, Faculty of Medicine, Fukuoka University, Fukuoka (Japan); Central Research Institute for Advanced Molecular Medicine, Fukuoka University, Fukuoka (Japan); Central Research Institute of Life Sciences for the Next Generation of Women Scientists, Fukuoka University, Fukuoka (Japan); Fujimoto, Takahiro [Department of Cell Biology, Faculty of Medicine, Fukuoka University, Fukuoka (Japan); Central Research Institute for Advanced Molecular Medicine, Fukuoka University, Fukuoka (Japan); Okamura, Tadashi [Division of Animal Models, Department of Infectious Diseases, Research Institute, National Center for Global Health and Medicine, Tokyo (Japan); Ogawa, Masahiro [Central Research Institute for Advanced Molecular Medicine, Fukuoka University, Fukuoka (Japan); Tanaka, Yoko [Department of Cell Biology, Faculty of Medicine, Fukuoka University, Fukuoka (Japan); Mototani, Yasumasa; Goto, Motohito [Division of Animal Models, Department of Infectious Diseases, Research Institute, National Center for Global Health and Medicine, Tokyo (Japan); Ota, Takeharu; Matsuzaki, Hiroshi [Department of Cell Biology, Faculty of Medicine, Fukuoka University, Fukuoka (Japan); Kuroki, Masahide [Central Research Institute for Advanced Molecular Medicine, Fukuoka University, Fukuoka (Japan); Tsunoda, Toshiyuki [Department of Cell Biology, Faculty of Medicine, Fukuoka University, Fukuoka (Japan); Central Research Institute for Advanced Molecular Medicine, Fukuoka University, Fukuoka (Japan); Sasazuki, Takehiko [Institute for Advanced Study, Kyushu University, Fukuoka (Japan); Shirasawa, Senji, E-mail: sshirasa@fukuoka-u.ac.jp [Department of Cell Biology, Faculty of Medicine, Fukuoka University, Fukuoka (Japan); Central Research Institute for Advanced Molecular Medicine, Fukuoka University, Fukuoka (Japan)

    2012-08-17

    Highlights: Black-Right-Pointing-Pointer We generated Cd4-Cre-mediated T cell-specific Zfat-deficient mice. Black-Right-Pointing-Pointer Zfat-deficiency leads to reduction in the number of the peripheral T cells. Black-Right-Pointing-Pointer Impaired T cell receptor-mediated response in Zfat-deficient peripheral T cells. Black-Right-Pointing-Pointer Decreased expression of IL-7R{alpha}, IL-2R{alpha} and IL-2 in Zfat-deficient peripheral T cells. Black-Right-Pointing-Pointer Zfat plays critical roles in peripheral T cell homeostasis. -- Abstract: ZFAT, originally identified as a candidate susceptibility gene for autoimmune thyroid disease, has been reported to be involved in apoptosis, development and primitive hematopoiesis. Zfat is highly expressed in T- and B-cells in the lymphoid tissues, however, its physiological function in the immune system remains totally unknown. Here, we generated the T cell-specific Zfat-deficient mice and demonstrated that Zfat-deficiency leads to a remarkable reduction in the number of the peripheral T cells. Intriguingly, a reduced expression of IL-7R{alpha} and the impaired responsiveness to IL-7 for the survival were observed in the Zfat-deficient T cells. Furthermore, a severe defect in proliferation and increased apoptosis in the Zfat-deficient T cells following T cell receptor (TCR) stimulation was observed with a reduced IL-2R{alpha} expression as well as a reduced IL-2 production. Thus, our findings reveal that Zfat is a critical regulator in peripheral T cell homeostasis and its TCR-mediated response.

  18. Surface deformation and shear flow in ligand mediated cell adhesion

    Science.gov (United States)

    Sircar, Sarthok; Roberts, Anthony; Sarthok Sircar / Anthony Roberts Collaboration

    We present a unified, multiscale model to study the attachment/detachment dynamics of two deforming, near spherical cells, coated with binding ligands and subject to a slow, homogeneous shear flow in a viscous fluid medium. The binding ligands on the surface of the cells experience attractive and repulsive forces in an ionic medium and exhibit finite resistance to rotation via bond tilting. The microscale drag forces and couples describing the fluid flow inside the small separation gap between the cells, are calculated using a combination of methods in lubrication theory and previously published numerical results. For a select range of material and fluid parameters, a hysteretic transition of the sticking probability curves (i.e., the function g*) between the adhesion phase (when g*>0.5) and the fragmentation phase (when g*University startup funds and AR is supported by the Australian Research Council Discovery Grant DP150102385.

  19. Photothermal Therapy of Cancer Cells mediated by Blue Hydrogel Nanoparticles

    Science.gov (United States)

    Curry, Taeyjuana; Epstein, Tamir; Kopelman, Raoul

    2012-10-01

    Coomassie Blue dye has been covalently linked into a polyacrylamide nanoparticle matrix, so as to form nontoxic, biologically compatible, biodegradable and cell-specific targetable nanoparticles for photothermal therapy (PTT) of cancer. The nanoparticles were found to be approximately 80-95 nm in diameter, with an absorbance value of 0.52. Using an inexpensive, low intensity LED array light source (590nm, 25mW/cm^2), with 20 minute excitation times, at 37 , PTT induced hyperthermia/thermolysis in HeLa cells, in vitro, resulting in virtually complete cell death when observed 3 hours after exposure. These multifunctional particles have been previously used in cancer delineation, for surgery, and in photoacoustic imaging studies; the addition of the PTT function now enables a multi-pronged medical approach to cancer.

  20. Identifying genes that mediate anthracyline toxicity in immune cells

    Directory of Open Access Journals (Sweden)

    Amber eFrick

    2015-04-01

    Full Text Available The role of the immune system in response to chemotherapeutic agents remains elusive. The interpatient variability observed in immune and chemotherapeutic cytotoxic responses is likely, at least in part, due to complex genetic differences. Through the use of a panel of genetically diverse mouse inbred strains, we developed a drug screening platform aimed at identifying genes underlying these chemotherapeutic cytotoxic effects on immune cells. Using genome-wide association studies (GWAS, we identified four genome-wide significant quantitative trait loci (QTL that contributed to the sensitivity of doxorubicin and idarubicin in immune cells. Of particular interest, a locus on chromosome 16 was significantly associated with cell viability following idarubicin administration (p = 5.01x10-8. Within this QTL lies App, which encodes amyloid beta precursor protein. Comparison of dose-response curves verified that T-cells in App knockout mice were more sensitive to idarubicin than those of C57BL/6J control mice (p < 0.05.In conclusion, the cellular screening approach coupled with GWAS led to the identification and subsequent validation of a gene involved in T-cell viability after idarubicin treatment. Previous studies have suggested a role for App in in vitro and in vivo cytotoxicity to anticancer agents; the overexpression of App enhances resistance, while the knockdown of this gene is deleterious to cell viability. Thus, further investigations should include performing mechanistic studies, validating additional genes from the GWAS, including Ppfia1 and Ppfibp1, and ultimately translating the findings to in vivo and human studies.

  1. B cell autophagy mediates TLR7-dependent autoimmunity and inflammation.

    Science.gov (United States)

    Weindel, Chi G; Richey, Lauren J; Bolland, Silvia; Mehta, Abhiruchi J; Kearney, John F; Huber, Brigitte T

    2015-01-01

    Systemic lupus erythematosus (SLE) is a heterogeneous autoimmune disease, defined by loss of B cell self-tolerance that results in production of antinuclear antibodies (ANA) and chronic inflammation. While the initiating events in lupus development are not well defined, overexpression of the RNA-recognizing toll-like receptor (TLR)7 has been linked to SLE in humans and mice. We postulated that autophagy plays an essential role in TLR7 activation of B cells for the induction of SLE by delivering RNA ligands to the endosomes, where this innate immune receptor resides. To test this hypothesis, we compared SLE development in Tlr7 transgenic (Tg) mice with or without B cell-specific ablation of autophagy (Cd19-Cre Atg5(f/f)). We observed that in the absence of B cell autophagy the 2 hallmarks of SLE, ANA and inflammation, were eliminated, thus curing these mice of lupus. This was also evident in the significantly extended survival of the autophagy-deficient mice compared to Tlr7.1 Tg mice. Furthermore, glomerulonephritis was ameliorated, and the serum levels of inflammatory cytokines in the knockout (KO) mice were indistinguishable from those of control mice. These data provide direct evidence that B cells require TLR7-dependent priming through an autophagy-dependent mechanism before autoimmunity is induced, thereafter involving many cell types. Surprisingly, hyper-IgM production persisted in Tlr7.1 Tg mice in the absence of autophagy, likely involving a different activation pathway than the production of autoantibodies. Furthermore, these mice still presented with anemia, but responded with a striking increase in extramedullary hematopoiesis (EMH), possibly due to the absence of pro-inflammatory cytokines.

  2. Effect of electron mediators on current generation and fermentation in a microbial fuel cell

    Energy Technology Data Exchange (ETDEWEB)

    Sund, C.J.; McMasters, S.; Crittenden, S.R.; Sumner, J.J. [Sensors and Electron Devices Directorate, Adelphi, MD (United States). US Army Research Laboratory; Harrell, L.E. [US Military Academy, West Point, NY (United States). Dept. of Physics

    2007-09-15

    Effects of select electron mediators [9,10-anthraquinone-2,6-disulfonic acid disodium salt (AQDS), safranine O, resazurin, methylene blue, and humic acids] on metabolic end-products and current production from cellulose digestion by Clostridium cellulolyticum in microbial fuel cells (MFCs) were studied using capillary electrophoresis and traditional electrochemical techniques. Addition of the mediator resazurin greatly enhanced current production but did not appear to alter the examined fermentation end-products compared to MFCs with no mediator. Assays for lactate, acetate, and ethanol indicate that the presence of safranine O, methylene blue, and humic acids alters metabolite production in the MFC: safranine O decreased the examined metabolites, methylene blue increased lactate formation, and humic acids increased the examined metabolites. Mediator standard redox potentials (E{sub 0}) reported in the literature do not coincide with redox potentials in MFCs due presumably to the electrolytic complexity of media that supports bacterial survival and growth. Current production in MFCs: (1) can be effected by the mediator redox potential while in the media, which may be significantly shifted from E{sub 0}, and (2) depended on the ability of the mediator to access the bacterial electron source, which may be cytoplasmic. In addition, some electron mediators had significant effects on metabolic end-products and therefore the metabolism of the organism itself.

  3. Involvement of Hydrogen Peroxide in Safingol-Induced Endonuclease G-Mediated Apoptosis of Squamous Cell Carcinoma Cells

    Directory of Open Access Journals (Sweden)

    Masakazu Hamada

    2014-02-01

    Full Text Available Safingol, a L-threo-dihydrosphingosine, induced the nuclear translocation of a mitochondrial apoptogenic mediator—endonuclease G (endo G—and apoptosis of human oral squamous cell carcinoma (SCC cells. Upstream mediators remain largely unknown. The levels of hydrogen peroxide (H2O2 in cultured oral SCC cells were measured. Treatment with safingol increased intracellular H2O2 levels but not extracellular H2O2 levels, indicating the production of H2O2. The cell killing effect of safingol and H2O2 was diminished in the presence of reactive oxygen species (ROS scavenger N-acetyl-L-cysteine (NAC. Dual staining of cells with annexin V and propidium iodide (PI revealed that apoptotic cell death occurred by treatment with H2O2 and safingol. The number of apoptotic cells was reduced in the presence of NAC. In untreated cells, endo G distributed in the cytoplasm and an association of endo G with mitochondria was observed. After treatment with H2O2 and safingol, endo G was distributed to the nucleus and cytoplasm, indicating the nuclear translocation of the mitochondrial factor. NAC prevented the increase of apoptotic cells and the translocation of endo G. Knock down of endo G diminished the cell killing effect of H2O2 and safingol. These results suggest that H2O2 is involved in the endo G-mediated apoptosis of oral SCC cells by safingol.

  4. Stem cell mediation of functional recovery after stroke in the rat.

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    Pedro Ramos-Cabrer

    Full Text Available BACKGROUND: Regenerative strategies of stem cell grafting have been demonstrated to be effective in animal models of stroke. In those studies, the effectiveness of stem cells promoting functional recovery was assessed by behavioral testing. These behavioral studies do, however, not provide access to the understanding of the mechanisms underlying the observed functional outcome improvement. METHODOLOGY/PRINCIPAL FINDINGS: In order to address the underlying mechanisms of stem cell mediated functional improvement, this functional improvement after stroke in the rat was investigated for six months after stroke by use of fMRI, somatosensory evoked potentials by electrophysiology, and sensorimotor behavior testing. Stem cells were grafted ipsilateral to the ischemic lesion. Rigorous exclusion of spontaneous recovery as confounding factor permitted to observe graft-related functional improvement beginning after 7 weeks and continuously increasing during the 6-month observation period. The major findings were i functional improvement causally related to the stem cells grafting; ii tissue replacement can be excluded as dominant factor for stem cell mediated functional improvement; iii functional improvement occurs by exclusive restitution of the function in the original representation field, without clear contributions from reorganization processes, and iv stem cells were not detectable any longer after six months. CONCLUSIONS/SIGNIFICANCE: A delayed functional improvement due to stem cell implantation has been documented by electrophysiology, fMRI and behavioral testing. This functional improvement occurred without cells acting as a tissue replacement for the necrotic tissue after the ischemic event. Combination of disappearance of grafted cells after six months on histological sections with persistent functional recovery was interpreted as paracrine effects by the grafted stem cells being the dominant mechanism of cell activity underlying the observed

  5. Consolidation out of Diversification in Narratology

    Directory of Open Access Journals (Sweden)

    Dan Shen

    2013-12-01

    Full Text Available Although the field of narratology is increasingly diversified with the appearance of various new approaches and new models, it has more elements of consolidation than the picture appears to be. I will discuss three aspects of consolidation: (1 how postclassical narratologies consolidate classical narrative poetics; (2 how the cognitive approach to unreliability consolidates the rhetorical criterion of unreliability and, moreover, how the rhetorical approach consolidates the cognitive concern with individual readers; and (3 how the Chinese classification of modes of discourse presentation consolidates its Western counterpart.

  6. Quasi natural consolidation of poorly consolidated oil field reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Larsen, T.; Lioliou, M.; Joesang, L. O.; Oestvold, T.

    2006-03-15

    A new method to prevent sand permeation from unconsolidated or poorly consolidated reservoir formations has been developed. The Quasi Natural Consolidation (QNC)-method involves a controlled in situ precipitation of calcium carbonate on sand grains. Experiments show that calcium carbonate forms bridges between sand grains and strengthens the unconsolidated sand pack. The QNC-solution contains Ca{sup 2+}, a CO{sub 3}{sup 2-} source and a catalyst. When this single-phase solution is injected into the sand pack, calcium carbonate precipitates at a rate which is dependent on the catalyst concentration and the temperature. A series of batch experiments have been carried out in order to establish the optimum solution chemistry/composition for sand consolidation. Consolidation experiments have shown that this method is applicable in the temperature range from 25 deg C to at least 65 deg C. An untreated sand pack will collapse at a water flow velocity of less than 0.01 cm/s (Q/A{sub tot}). However, after one QNC-injection at 50 deg C for 24 hours a sand pack could withstand a water flow velocity of 0.38 cm/s without producing sand. The initial and end permeability of this sand pack was respectively approx. 10 and approx. 7 Darcy. Uniaxial compressive strengths of 10.56, 8.69 and 4.80Mpa were achieved after four QNC-injections at respectively 25, 50 and 65 deg C. A sand pack treated with four QNC-injections at 50 deg C withstood 28 days of water flooding at 15 deg C without any sand production or dissolution of the precipitated calcium carbonate. Preliminary results have shown that consolidation can be achieved also with oil present in the sand pack. (Author)

  7. Effect of Biophytum sensitivum on cell-mediated immune response in mice.

    Science.gov (United States)

    Guruvayoorappan, C; Kuttan, G

    2007-01-01

    Effect of Biophytum sensitivum on cell-mediated immune response was studied in normal as well as Ehrlich ascites tumor bearing BALB/c mice. Administration of Biophytum sensitivum significantly enhanced the proliferation of splenocytes, thymocytes and bone marrow cells by stimulating the mitogenic potential of various mitogens such as Lipopolysaccharide (LPS), Concanavalin A (Con A), Phytohaemagglutinin (PHA) and Poke Weed Mitogen (PWM). Natural killer (NK) cell activity was enhanced significantly by Biophytum sensitivum in both the normal (43.6% cell lysis on day 5) and the tumor bearing group (48.2% cell lysis on day 5), and it was found to be earlier than tumor bearing control animals (maximum of 13.4% cell lysis on day 9). Antibody dependent cellular cytotoxicity (ADCC) was also enhanced significantly in both Biophytum treated normal (35% cell lysis on day 7) as well as tumor bearing animals (40.2% cell lysis on day 7) compared to untreated control tumor bearing animals (maximum of 12.3% cell lysis on day 11). An early antibody dependent complement mediated cytotoxicity (ACC) was also observed in the Biophytum treated normal (22.6% cell lysis, on day 15) and tumor bearing animals (26.4% cell lysis, on day 15). Results of our present study suggest the immunomodulatory property of Biophytum sensitivum. PMID:18075848

  8. The Role of Antioxidation and Immunomodulation in Postnatal Multipotent Stem Cell-Mediated Cardiac Repair

    Directory of Open Access Journals (Sweden)

    Johnny Huard

    2013-08-01

    Full Text Available Oxidative stress and inflammation play major roles in the pathogenesis of coronary heart disease including myocardial infarction (MI. The pathological progression following MI is very complex and involves a number of cell populations including cells localized within the heart, as well as cells recruited from the circulation and other tissues that participate in inflammatory and reparative processes. These cells, with their secretory factors, have pleiotropic effects that depend on the stage of inflammation and regeneration. Excessive inflammation leads to enlargement of the infarction site, pathological remodeling and eventually, heart dysfunction. Stem cell therapy represents a unique and innovative approach to ameliorate oxidative stress and inflammation caused by ischemic heart disease. Consequently, it is crucial to understand the crosstalk between stem cells and other cells involved in post-MI cardiac tissue repair, especially immune cells, in order to harness the beneficial effects of the immune response following MI and further improve stem cell-mediated cardiac regeneration. This paper reviews the recent findings on the role of antioxidation and immunomodulation in postnatal multipotent stem cell-mediated cardiac repair following ischemic heart disease, particularly acute MI and focuses specifically on mesenchymal, muscle and blood-vessel-derived stem cells due to their antioxidant and immunomodulatory properties.

  9. Cutting edge: Human regulatory T cells require IL-35 to mediate suppression and infectious tolerance.

    Science.gov (United States)

    Chaturvedi, Vandana; Collison, Lauren W; Guy, Clifford S; Workman, Creg J; Vignali, Dario A A

    2011-06-15

    Human regulatory T cells (T(reg)) are essential for the maintenance of immune tolerance. However, the mechanisms they use to mediate suppression remain controversial. Although IL-35 has been shown to play an important role in T(reg)-mediated suppression in mice, recent studies have questioned its relevance in human T(reg). In this study, we show that human T(reg) express and require IL-35 for maximal suppressive capacity. Substantial upregulation of EBI3 and IL12A, but not IL10 and TGFB, was observed in activated human T(reg) compared with conventional T cells (T(conv)). Contact-independent T(reg)-mediated suppression was IL-35 dependent and did not require IL-10 or TGF-β. Lastly, human T(reg)-mediated suppression led to the conversion of the suppressed T(conv) into iTr35 cells, an IL-35-induced T(reg) population, in an IL-35-dependent manner. Thus, IL-35 contributes to human T(reg)-mediated suppression, and its conversion of suppressed target T(conv) into IL-35-induced T(reg) may contribute to infectious tolerance.

  10. Glycan elongation beyond the mucin associated Tn antigen protects tumor cells from immune-mediated killing.

    Directory of Open Access Journals (Sweden)

    Caroline B Madsen

    Full Text Available Membrane bound mucins are up-regulated and aberrantly glycosylated during malignant transformation in many cancer cells. This results in a negatively charged glycoprotein coat which may protect cancer cells from immune surveillance. However, only limited data have so far demonstrated the critical steps in glycan elongation that make aberrantly glycosylated mucins affect the interaction between cancer cells and cytotoxic effector cells of the immune system. Tn (GalNAc-Ser/Thr, STn (NeuAcα2-6GalNAc-Ser/Thr, T (Galβ1-3GalNAc-Ser/Thr, and ST (NeuAcα2-6Galβ1-3GalNAc-Ser/Thr antigens are recognized as cancer associated truncated glycans, and are expressed in many adenocarcinomas, e.g. breast- and pancreatic cancer cells. To investigate the role of the cancer associated glycan truncations in immune-mediated killing we created glyco-engineered breast- and pancreatic cancer cells expressing only the shortest possible mucin-like glycans (Tn and STn. Glyco-engineering was performed by zinc finger nuclease (ZFN knockout (KO of the Core 1 enzyme chaperone COSMC, thereby preventing glycan elongation beyond the initial GalNAc residue in O-linked glycans. We find that COSMC KO in the breast and pancreatic cancer cell lines T47D and Capan-1 increases sensitivity to both NK cell mediated antibody-dependent cellular-cytotoxicity (ADCC and cytotoxic T lymphocyte (CTL-mediated killing. In addition, we investigated the association between total cell surface expression of MUC1/MUC16 and NK or CTL mediated killing, and observed an inverse correlation between MUC16/MUC1 expression and the sensitivity to ADCC and CTL-mediated killing. Together, these data suggest that up-regulation of membrane bound mucins protects cells from immune mediated killing, and that particular glycosylation steps, as demonstrated for glycan elongation beyond Tn and STn, can be important for fine tuning of the immune escape mechanisms in cancer cells.

  11. CRISPR/Cas9-mediated genome editing of Epstein-Barr virus in human cells.

    Science.gov (United States)

    Yuen, Kit-San; Chan, Chi-Ping; Wong, Nok-Hei Mickey; Ho, Chau-Ha; Ho, Ting-Hin; Lei, Ting; Deng, Wen; Tsao, Sai Wah; Chen, Honglin; Kok, Kin-Hang; Jin, Dong-Yan

    2015-03-01

    The CRISPR (clustered regularly interspaced short palindromic repeats)/Cas9 (CRISPR-associated 9) system is a highly efficient and powerful tool for RNA-guided editing of the cellular genome. Whether CRISPR/Cas9 can also cleave the genome of DNA viruses such as Epstein-Barr virus (EBV), which undergo episomal replication in human cells, remains to be established. Here, we reported on CRISPR/Cas9-mediated editing of the EBV genome in human cells. Two guide RNAs (gRNAs) were used to direct a targeted deletion of 558 bp in the promoter region of BART (BamHI A rightward transcript) which encodes viral microRNAs (miRNAs). Targeted editing was achieved in several human epithelial cell lines latently infected with EBV, including nasopharyngeal carcinoma C666-1 cells. CRISPR/Cas9-mediated editing of the EBV genome was efficient. A recombinant virus with the desired deletion was obtained after puromycin selection of cells expressing Cas9 and gRNAs. No off-target cleavage was found by deep sequencing. The loss of BART miRNA expression and activity was verified, supporting the BART promoter as the major promoter of BART RNA. Although CRISPR/Cas9-mediated editing of the multicopy episome of EBV in infected HEK293 cells was mostly incomplete, viruses could be recovered and introduced into other cells at low m.o.i. Recombinant viruses with an edited genome could be further isolated through single-cell sorting. Finally, a DsRed selectable marker was successfully introduced into the EBV genome during the course of CRISPR/Cas9-mediated editing. Taken together, our work provided not only the first genetic evidence that the BART promoter drives the expression of the BART transcript, but also a new and efficient method for targeted editing of EBV genome in human cells.

  12. Riluzole mediates anti-tumor properties in breast cancer cells independent of metabotropic glutamate receptor-1.

    Science.gov (United States)

    Speyer, Cecilia L; Nassar, Mahdy A; Hachem, Ali H; Bukhsh, Miriam A; Jafry, Waris S; Khansa, Rafa M; Gorski, David H

    2016-06-01

    Riluzole, the only drug approved by the FDA for treating amyotrophic lateral sclerosis, inhibits melanoma proliferation through its inhibitory effect on glutamatergic signaling. We demonstrated that riluzole also inhibits the growth of triple-negative breast cancer (TNBC) and described a role for metabotropic glutamate receptor-1 (GRM1) in regulating TNBC cell growth and progression. However, the role of GRM1 in mediating riluzole's effects in breast cancer has not been fully elucidated. In this study, we seek to determine how much of riluzole's action in breast cancer is mediated through GRM1. We investigated anti-tumor properties of riluzole in TNBC and ER+ cells using cell growth, invasion, and soft-agar assays and compared riluzole activity with GRM1 levels. Using Lentiviral vectors expressing GRM1 or shGRM1, these studies were repeated in cells expressing high or low GRM1 levels where the gene was either silenced or overexpressed. Riluzole inhibited proliferation, invasion, and colony formation in both TNBC and ER+ cells. There was a trend between GRM1 expression in TNBC cells and their response to riluzole in both cell proliferation and invasion assays. However, silencing and overexpression studies had no effect on cell sensitivity to riluzole. Our results clearly suggest a GRM1-independent mechanism through which riluzole mediates its effects on breast cancer cells. Understanding the mechanism by which riluzole mediates breast cancer progression will be useful in identifying new therapeutic targets for treating TNBC and in facilitating stratification of patients in clinical trials using riluzole in conjunction with conventional therapy. PMID:27146584

  13. Tetraspanin CD151 Is a Negative Regulator of FcεRI-Mediated Mast Cell Activation.

    Science.gov (United States)

    Abdala-Valencia, Hiam; Bryce, Paul J; Schleimer, Robert P; Wechsler, Joshua B; Loffredo, Lucas F; Cook-Mills, Joan M; Hsu, Chia-Lin; Berdnikovs, Sergejs

    2015-08-15

    Mast cells are critical in the pathogenesis of allergic disease due to the release of preformed and newly synthesized mediators, yet the mechanisms controlling mast cell activation are not well understood. Members of the tetraspanin family are recently emerging as modulators of FcεRI-mediated mast cell activation; however, mechanistic understanding of their function is currently lacking. The tetraspanin CD151 is a poorly understood member of this family and is specifically induced on mouse and human mast cells upon FcεRI aggregation but its functional effects are unknown. In this study, we show that CD151 deficiency significantly exacerbates the IgE-mediated late phase inflammation in a murine model of passive cutaneous anaphylaxis. Ex vivo, FcεRI stimulation of bone marrow-derived mast cells from CD151(-/-) mice resulted in significantly enhanced expression of proinflammatory cytokines IL-4, IL-13, and TNF-α compared with wild-type controls. However, FcεRI-induced mast cell degranulation was unaffected. At the molecular signaling level, CD151 selectively regulated IgE-induced activation of ERK1/2 and PI3K, associated with cytokine production, but had no effect on the phospholipase Cγ1 signaling, associated with degranulation. Collectively, our data indicate that CD151 exerts negative regulation over IgE-induced late phase responses and cytokine production in mast cells. PMID:26136426

  14. Effector CD4+ T cell expression signatures and immune-mediated disease associated genes.

    Directory of Open Access Journals (Sweden)

    Wei Zhang

    Full Text Available Genome-wide association studies (GWAS in immune-mediated diseases have identified over 150 associated genomic loci. Many of these loci play a role in T cell responses, and regulation of T cell differentiation plays a critical role in immune-mediated diseases; however, the relationship between implicated disease loci and T cell differentiation is incompletely understood. To further address this relationship, we examined differential gene expression in naïve human CD4+ T cells, as well as in in vitro differentiated Th1, memory Th17-negative and Th17-enriched CD4+ T cells subsets using microarray and RNASeq. We observed a marked enrichment for increased expression in memory CD4+ compared to naïve CD4+ T cells of genes contained among immune-mediated disease loci. Within memory T cells, expression of disease-associated genes was typically increased in Th17-enriched compared to Th17-negative cells. Utilizing RNASeq and promoter methylation studies, we identified a differential regulation pattern for genes solely expressed in Th17 cells (IL17A and CCL20 compared to genes expressed in both Th17 and Th1 cells (IL23R and IL12RB2, where high levels of promoter methylation are correlated to near zero RNASeq levels for IL17A and CCL20. These findings have implications for human Th17 celI plasticity and for the regulation of Th17-Th1 expression signatures. Importantly, utilizing RNASeq we found an abundant isoform of IL23R terminating before the transmembrane domain that was enriched in Th17 cells. In addition to molecular resolution, we find that RNASeq provides significantly improved power to define differential gene expression and identify alternative gene variants relative to microarray analysis. The comprehensive integration of differential gene expression between cell subsets with disease-association signals, and functional pathways provides insight into disease pathogenesis.

  15. TGF-β1/SMAD SIGNALING PATHWAY MEDIATES p53-DEPENDENT APOPTOSIS IN HEPATOMA CELL LINES

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Objective To determine whether transforming growth factor betal ( TGF-β1 )/Smad signaling pathway mediates p53-dependent apoptosis in hepatoma cell lines. Methods Three human hepatic carcinoma cell lines, HepG2, Huh-7, and Hep3B, were used in this study. TGF-β31-induced apoptosis in hepatic carcinoma cell lines was analyzed using TUNEL assay. For identifying the mechanism of apoptosis induced by TGF-β1, cell lines were transfected with a TGF-β1-inducible luciferase reportor plasmid containing Smad4 binding elements. After transfection, cells were treated with TGF-β1, then assayed for luciferase activity. Results The apoptosis rate of HepG2 cell lines (48.51% ± 8.21% ) was significantly higher than control (12. 72% ±2. 18%, P <0. 05 ). But TGF-β1 was not able to induce apoptosis of Huh-7 and Hep3B cell lines. The relative luciferase activity of TGF-β1-treated HepG2 cell lines (4. 38) was significantly higher than control (1.00, P <0. 05). But the relative luciferase activity of TGF-β1-treated Huh-7 and Hep3B cell lines less increased compared with control. Conclusions HepG2 cells seem to be highly susceptible to TGF-β1-induced apoptosis compared with Hep3B and Huh-7 cell lines. Smad4 is a central mediator of TGF-β1 signaling transdution pathway. TGF-β1/Smad signaling pathway might mediate p53-dependent apoptosis in hepatoma cell lines.

  16. Prostate cancer cell-stromal cell crosstalk via FGFR1 mediates antitumor activity of dovitinib in bone metastases.

    Science.gov (United States)

    Wan, Xinhai; Corn, Paul G; Yang, Jun; Palanisamy, Nallasivam; Starbuck, Michael W; Efstathiou, Eleni; Li Ning Tapia, Elsa M; Tapia, Elsa M Li-Ning; Zurita, Amado J; Aparicio, Ana; Ravoori, Murali K; Vazquez, Elba S; Robinson, Dan R; Wu, Yi-Mi; Cao, Xuhong; Iyer, Matthew K; McKeehan, Wallace; Kundra, Vikas; Wang, Fen; Troncoso, Patricia; Chinnaiyan, Arul M; Logothetis, Christopher J; Navone, Nora M

    2014-09-01

    Bone is the most common site of prostate cancer (PCa) progression to a therapy-resistant, lethal phenotype. We found that blockade of fibroblast growth factor receptors (FGFRs) with the receptor tyrosine kinase inhibitor dovitinib has clinical activity in a subset of men with castration-resistant PCa and bone metastases. Our integrated analyses suggest that FGF signaling mediates a positive feedback loop between PCa cells and bone cells and that blockade of FGFR1 in osteoblasts partially mediates the antitumor activity of dovitinib by improving bone quality and by blocking PCa cell-bone cell interaction. These findings account for clinical observations such as reductions in lesion size and intensity on bone scans, lymph node size, and tumor-specific symptoms without proportional declines in serum prostate-specific antigen concentration. Our findings suggest that targeting FGFR has therapeutic activity in advanced PCa and provide direction for the development of therapies with FGFR inhibitors.

  17. An evidence for adhesion-mediated acquisition of acute myeloid leukemic stem cell-like immaturities

    Energy Technology Data Exchange (ETDEWEB)

    Funayama, Keiji; Shimane, Miyuki; Nomura, Hitoshi [Department of Integrative Bioscience and Biomedical Engineering, Waseda University, 4-3-1 Ohkubo, Shinjuku-ku, Tokyo 169-8555 (Japan); Asano, Shigetaka, E-mail: asgtkmd@waseda.jp [Department of Integrative Bioscience and Biomedical Engineering, Waseda University, 4-3-1 Ohkubo, Shinjuku-ku, Tokyo 169-8555 (Japan)

    2010-02-12

    For long-term survival in vitro and in vivo of acute myeloid leukemia cells, their adhesion to bone marrow stromal cells is indispensable. However, it is still unknown if these events are uniquely induced by the leukemic stem cells. Here we show that TF-1 human leukemia cells, once they have formed a cobblestone area by adhering to mouse bone marrow-derived MS-5 cells, can acquire some leukemic stem cell like properties in association with a change in the CD44 isoform-expression pattern and with an increase in a set of related microRNAs. These findings strongly suggest that at least some leukemia cells can acquire leukemic stem cell like properties in an adhesion-mediated stochastic fashion.

  18. Cell-Mediated Immunity Imbalance in Patients with Intrahepatic Cholestasis of Pregnancy

    Institute of Scientific and Technical Information of China (English)

    Bin Ling; Fengqiu Yao; Ying Zhou; Zhengzheng Chen; Guodong Shen; Yuanyuan Zhu

    2007-01-01

    Decidual lymphocytes may mediate fetal trophoblast recognition and regulate maternal immune reaction and play an essential role in the maintenance of normal pregnancy. The aim of this study was to compare the percentage of T cells, natural killer (NK) cells and natural killer T (NKT) cells within decidual parietalis of normal pregnant controls (NP) and patients with intraheptic cholestasis of pregnancy (ICP), and to investigate the production of interleukin-4 (IL-4), interferon-γ (IFN-γ) in the culture supernatant of decidual parietalis mononuclear cells (DPMCs). Compared with controls, the decidua parietalis from ICP were characterized with significant increased percentages of CD3-CD56+ cells, CD3+CD56+ cells, CD56+CD16+ cells, CD56+CD16- cells, CD56+NKG2D+ cells, and the significant decreased percentages of CD3+ cells, CD3+CD4+ cells. There were no differences found for the percentage of CD3+CD8+ cells, CD56+NKG2A+ cells between control and study group. In addition, the enhanced concentration of IFN-γ was presented in culture supernatant of DPMCs from ICP. It was suggested that the increased NK cells, NKT cells and the decreased T cells in the decidual parietalis and over-secretion of IFN-γ could be correlated with the pathophysiology of ICP patients.

  19. Histamine stimulates calcium-mediated protein phosphorylation in a colonic epithelial cell line.

    Science.gov (United States)

    Cohn, J A; Dougherty, N C; King, W F

    1989-12-15

    Protein phosphorylation responses in intact enterocytes were examined by stimulating 32Pi-labeled T84 cell monolayers with histamine and resolving proteins by two-dimensional gel electrophoresis. Histamine increases 32P-incorporation into two acidic proteins of Mr 83,000 and of Mr 29,000, designated p83 and p29. Labeling of p83 and p29 is also increased in cells exposed to ionomycin, but not in cells exposed to vasoactive intestinal peptide under conditions resulting in cAMP-mediated secretion and cAMP-stimulated protein phosphorylation. When T84 cell fractions are incubated with [gamma-32P]ATP, labeling of p83 is stimulated by Ca++, but not by cAMP. Thus, histamine stimulates Ca++-mediated protein phosphorylation during the regulation of Cl- secretion.

  20. Explanatory style and cell-mediated immunity in elderly men and women.

    Science.gov (United States)

    Kamen-Siegel, L; Rodin, J; Seligman, M E; Dwyer, J

    1991-01-01

    Correlated pessimistic explanatory style--the belief that negative events are caused by internal, stable, and global factors--with lowered immunocompetence in a sample of 26 older adults. Two measures of cell-mediated immunity--T-helper cell/T-suppressor cell ratio and T-lymphocyte response to mitogen challenge--were lower in individuals with a pessimistic style, controlling for the influence of current health, depression, medication, recent weight change, sleep, and alcohol use. A relative increase in the percentage of T-suppressor cells seemed to underlie this immunosuppression. Although the mechanism by which explanatory style might influence immune function remains unknown, we speculate that a pessimistic style might be an important psychological risk factor--at least among older people--in the early course of certain immune-mediated diseases. PMID:1915208

  1. UV stimulation of DNA-mediated transformation of human cells

    International Nuclear Information System (INIS)

    Irradiation of dominant marker DNA with UV light (150 to 1,000 J/m2) was found to stimulate the transformation of human cells by this marker from two- to more than fourfold. This phenomenon is also displayed by xeroderma pigmentosum cells, which are deficient in the excision repair of UV-induced pyrimidine dimers in the DNA. Also, exposure to UV of the transfected (xeroderma pigmentosum) cells enhanced the transfection efficiency. Removal of the pyrimidine dimers from the DNA by photoreactivating enzyme before transfection completely abolished the stimulatory effect, indicating that dimer lesions are mainly responsible for the observed enhancement. A similar stimulation of the transformation efficiency is exerted by 2-acetoxy-2-acetylaminofluorene modification of the DNA. These findings suggest that lesions which are targets for the excision repair pathway induce the increase in transformation frequency. The stimulation was found to be independent of sequence homology between the irradiated DNA and the host chromosomal DNA. Therefore, the increase of the transformation frequency is not caused by a mechanism inducing homologous recombination between these two DNAs. UV treatment of DNA before transfection did not have a significant effect on the amount of DNA integrated into the xeroderma pigmentosum genome

  2. Wnt3a is critical for endothelial progenitor cell-mediated neural stem cell proliferation and differentiation

    Science.gov (United States)

    Du, Yibin; Zhang, Shuo; Yu, Tao; Du, Gongwen; Zhang, Hui; Yin, Zongsheng

    2016-01-01

    The present study aimed to determine whether co-culture with bone marrow-derived endothelial progenitor cells (EPCs) affects the proliferation and differentiation of spinal cord-derived neural stem cells (NSCs), and to investigate the underlying mechanism. The proliferation and differentiation of the NSCs were evaluated by an MTT cell proliferation and cytotoxicity assay, and immunofluorescence, respectively. The number of neurospheres and the number of β-tubulin III-positive cells were detected by microscopy. The wingless-type MMTV integration site family, member 3a (Wnt3a)/β-catenin signaling pathway was analyzed by western blot analysis and reverse transcription-quantitative polymerase chain reaction to elucidate the possible mechanisms of EPC-mediated NSC proliferation and differentiation. The results revealed that co-culture with EPCs significantly induced NSC proliferation and differentiation. In addition, co-culture with EPCs markedly induced the expression levels of Wnt3a and β-catenin and inhibited the phosphorylation of glycogen synthase kinase 3β (GSK-3β). By contrast, Wnt3a knockdown using a short hairpin RNA plasmid in the EPCs reduced EPC-mediated NSC proliferation and differentiation, accompanied by inhibition of the EPC-mediated expression of β-catenin, and its phosphorylation and activation of GSK-3β. Taken together, the findings of the present study demonstrated that Wnt3a was critical for EPC-mediated NSC proliferation and differentiation. PMID:27484039

  3. A Phase I Study of Reduced-Intensity Conditioning and Allogeneic Stem Cell Transplantation Followed by Dose Escalation of Targeted Consolidation Immunotherapy with Gemtuzumab Ozogamicin in Children and Adolescents with CD33+ Acute Myeloid Leukemia.

    Science.gov (United States)

    Zahler, Stacey; Bhatia, Monica; Ricci, Angela; Roy, Sumith; Morris, Erin; Harrison, Lauren; van de Ven, Carmella; Fabricatore, Sandra; Wolownik, Karen; Cooney-Qualter, Erin; Baxter-Lowe, Lee Ann; Luisi, Paul; Militano, Olga; Kletzel, Morris; Cairo, Mitchell S

    2016-04-01

    Myeloablative conditioning and allogeneic hematopoietic stem cell transplant (alloHSCT) in children with acute myeloid leukemia (AML) in first complete remission (CR1) may be associated with significant acute toxicity and late effects. Reduced-intensity conditioning (RIC) and alloHSCT in children is safe, feasible, and may be associated with less adverse effects. Gemtuzumab ozogamicin (GO) induces a response in 30% of patients with CD33+ relapsed/refractory AML. The dose of GO is significantly lower when combined with chemotherapy. We examined the feasibility and toxicity of RIC alloHSCT followed by GO targeted immunotherapy in children with CD33+ AML in CR1/CR2. Conditioning consisted of fludarabine 30 mg/m2 × 6 days, busulfan 3.2 to 4 mg/kg × 2 days ± rabbit antithymocyte globulin 2 mg/kg × 4 days followed by alloHSCT from matched related/unrelated donors. GO was administered ≥60 days after alloHSCT in 2 doses (8 weeks apart), following a dose-escalation design (4.5, 6, 7.5, and 9 mg/m2). Fourteen patients with average risk AML received RIC alloHSCT and post-GO consolidation: median age 13.5 years at transplant (range, 1 to 21), male-to-female 8:6, and disease status at alloHSCT 11 CR1 and 3 CR2. Eleven patients received alloHSCT from 5-6/6 HLA-matched family donors: 8 received peripheral blood stem cells, 2 received bone marrow, and 1 received related cord blood transplantation. Three patients received an unrelated allograft (two 4-5/6 and one 9/10) from unrelated cord blood unit and bone marrow, respectively. Neutrophil and platelet engraftment was observed in all assessable patients (100%), achieved at median 15.5 days (range, 7 to 31) and 21 days (range, 10 to 52), respectively. Three patients received GO at dose level 1 (4.5 mg/m2 per dose), 5 at dose level 2 (6 mg/m2 per dose), 3 at dose level 3 (7.5 mg/m2 per dose), and 3 at dose level 4 (9 mg/m2 per dose). Three of 14 patients received only 1 dose of GO after alloHSCT. One patient experienced grade

  4. Measles Virus Spread by Cell-Cell Contacts: Uncoupling of Contact-Mediated Receptor (CD46) Downregulation from Virus Uptake

    OpenAIRE

    firsching, Ruth; Christian J Buchholz; Schneider, Urs; Cattaneo, Roberto; ter Meulen, Volker; Schneider-Schaulies, Jürgen

    1999-01-01

    CD46, which serves as a receptor for measles virus (MV; strain Edmonston), is rapidly downregulated from the cell surface after contact with viral particles or infected cells. We show here that the same two CD46 complement control protein (CCP) domains responsible for primary MV attachment mediate its downregulation. Optimal downregulation efficiency was obtained with CD46 recombinants containing CCP domains 1 and 2, whereas CCP 1, alone and duplicated, induced a slight downregulation. Using ...

  5. Cre-inducible human CD59 mediates rapid cell ablation after intermedilysin administration.

    Science.gov (United States)

    Feng, Dechun; Dai, Shen; Liu, Fengming; Ohtake, Yosuke; Zhou, Zhou; Wang, Hua; Zhang, Yonggang; Kearns, Alison; Peng, Xiao; Zhu, Faliang; Hayat, Umar; Li, Man; He, Yong; Xu, Mingjiang; Zhao, Chunling; Cheng, Min; Zhang, Lining; Wang, Hong; Yang, Xiaofeng; Ju, Cynthia; Bryda, Elizabeth C; Gordon, Jennifer; Khalili, Kamel; Hu, Wenhui; Li, Shuxin; Qin, Xuebin; Gao, Bin

    2016-06-01

    Cell ablation is a powerful tool for studying cell lineage and/or function; however, current cell-ablation models have limitations. Intermedilysin (ILY), a cytolytic pore-forming toxin that is secreted by Streptococcus intermedius, lyses human cells exclusively by binding to the human complement regulator CD59 (hCD59), but does not react with CD59 from nonprimates. Here, we took advantage of this feature of ILY and developed a model of conditional and targeted cell ablation by generating floxed STOP-CD59 knockin mice (ihCD59), in which expression of human CD59 only occurs after Cre-mediated recombination. The administration of ILY to ihCD59+ mice crossed with various Cre-driver lines resulted in the rapid and specific ablation of immune, epithelial, or neural cells without off-target effects. ILY had a large pharmacological window, which allowed us to perform dose-dependent studies. Finally, the ILY/ihCD59-mediated cell-ablation method was tested in several disease models to study immune cell functionalities, hepatocyte and/or biliary epithelial damage and regeneration, and neural cell damage. Together, the results of this study demonstrate the utility of the ihCD59 mouse model for studying the effects of cell ablation in specific organ systems in a variety of developmental and disease states. PMID:27159394

  6. AKT-mediated enhanced aerobic glycolysis causes acquired radioresistance by human tumor cells

    International Nuclear Information System (INIS)

    Background and purpose: Cellular radioresistance is a major impediment to effective radiotherapy. Here, we demonstrated that long-term exposure to fractionated radiation conferred acquired radioresistance to tumor cells due to AKT-mediated enhanced aerobic glycolysis. Material and methods: Two human tumor cell lines with acquired radioresistance were established by long-term exposure to fractionated radiation with 0.5 Gy of X-rays. Glucose uptake was inhibited using 2-deoxy-D-glucose, a non-metabolizable glucose analog. Aerobic glycolysis was assessed by measuring lactate concentrations. Cells were then used for assays of ROS generation, survival, and cell death as assessed by annexin V staining. Results: Enhanced aerobic glycolysis was shown by increased glucose transporter Glut1 expression and a high lactate production rate in acquired radioresistant cells compared with parental cells. Inhibiting the AKT pathway using the AKT inhibitor API-2 abrogated these phenomena. Moreover, we found that inhibiting glycolysis with 2-deoxy-D-glucose suppressed acquired tumor cell radioresistance. Conclusions: Long-term fractionated radiation confers acquired radioresistance to tumor cells by AKT-mediated alterations in their glucose metabolic pathway. Thus, tumor cell metabolic pathway is an attractive target to eliminate radioresistant cells and improve radiotherapy efficacy

  7. Involvement of the insular cortex in regulating glucocorticoid effects on memory consolidation of inhibitory avoidance training

    Directory of Open Access Journals (Sweden)

    Raquel eFornari

    2012-03-01

    Full Text Available Glucocorticoids are known to enhance the consolidation of memory of emotionally arousing experiences by acting upon a network of interconnected brain regions. Although animal studies typically do not consider the insular cortex (IC to be part of this network, the present findings indicate that the IC is importantly involved in regulating glucocorticoid effects on memory consolidation of emotionally arousing inhibitory avoidance training. The specific glucocorticoid receptor agonist RU 28362 (3 or 10 ng in 0.5 l infused bilaterally into the IC of male Sprague-Dawley rats immediately after one-trial inhibitory avoidance training dose-dependently enhanced 48-h retention performance. Moreover, training on the inhibitory avoidance task increased neuronal activity of the IC, as assessed by an increased number of cells expressing immunoreactivity for phosphorylated extracellular signal-regulated kinase 1/2 (pERK1/2. However, systemic administration of a memory-enhancing dose of corticosterone (1 mg/kg after inhibitory avoidance training rapidly reduced the number of pERK1/2-positive cells in the IC, suggesting that glucocorticoid administration reduces overall neuronal activity of the IC. To investigate which components of the inhibitory avoidance training experience were influenced by the intra-IC glucocorticoid administration, in the last experiment rats were trained on a modified inhibitory avoidance task in which context exposure and footshock training occur on two sequential days. RU 28362 administration into the IC enhanced later retention when infused immediately after either the context or footshock training. Thus, these findings indicate that the IC mediates glucocorticoid effects on the consolidation of memory of different components of inhibitory avoidance training and suggest that the IC might be an important element of the rodent brain network involved in emotional regulation of learning and memory.

  8. CELL-MEDIATED IMMUNE RESPONSES IN THE SEA-STAR ASTERIAS RUBENS (ECHINODERM

    Directory of Open Access Journals (Sweden)

    Michel Leclerc

    2012-01-01

    Full Text Available Cell-mediated immune responses occur in sea star system. In Asterias rubens it is said that B sea star lymphocytes and T sea star lymphocytes exist in the axial organ which can be considered as an ancestral lymphoid organ. In the same manner the origin of lymphocytes can be found in Invertebrates such as Echinodermal.

  9. A longitudinal study of cell-mediated immunity in pigs infected with porcine parvovirus

    DEFF Research Database (Denmark)

    Ladekjaer-Mikkelsen, A.S.; Nielsen, Jens

    2002-01-01

    Porcine parvovirus (PPV) is an ubiquitous pathogen causing reproductive failure in swine. Protection against reproductive failure caused by acute PPV infection has commonly been related to the presence of specific antibodies in the dam. However, the role of cell-mediated immunity during chronic PPV...

  10. IL-10 polymorphism and cell-mediated immune response to Chlamydia trachomatis

    DEFF Research Database (Denmark)

    Öhman, H.; Tiitinen, A; Halttunen, M.;

    2006-01-01

    background. To study a relationship between interleukin-10 (IL-10) promoter -1082 polymorphism and cell-mediated immune response during C trachomatis infection in vitro, lymphocyte proliferation and cytokine (IL-10, IFN-gamma, TNF-alpha, IL-2, IL-4 and IL-5) secretion were analysed in subjects with different...

  11. Role of very late antigen-1 in T-cell-mediated immunity to systemic viral infection

    DEFF Research Database (Denmark)

    Ørding Kauffmann, Susanne; Thomsen, Allan Randrup; Christensen, Jan Pravsgaard

    2006-01-01

    or their distribution between lymphoid and nonlymphoid organs. Regarding a functional role of VLA-1, we found that intracerebral infection of both VLA-1(-/-) and wild-type (wt) mice resulted in lethal T-cell-mediated meningitis, and quantitative and qualitative analyses of the cellular exudate did not reveal any...

  12. A Proteolytic Cascade Controls Lysosome Rupture and Necrotic Cell Death Mediated by Lysosome-Destabilizing Adjuvants

    OpenAIRE

    Jürgen Brojatsch; Heriberto Lima; Alak K Kar; Jacobson, Lee S.; Stefan M Muehlbauer; Kartik Chandran; Felipe Diaz-Griffero

    2014-01-01

    Recent studies have linked necrotic cell death and proteolysis of inflammatory proteins to the adaptive immune response mediated by the lysosome-destabilizing adjuvants, alum and Leu-Leu-OMe (LLOMe). However, the mechanism by which lysosome-destabilizing agents trigger necrosis and proteolysis of inflammatory proteins is poorly understood. The proteasome is a cellular complex that has been shown to regulate both necrotic cell death and proteolysis of inflammatory proteins. We found that the p...

  13. Protection against murine disseminated candidiasis mediated by a Candida albicans-specific T-cell line.

    OpenAIRE

    Sieck, T G; Moors, M A; Buckley, H R; Blank, K J

    1993-01-01

    The role of T lymphocytes in disseminated candidiasis in a mouse model of irradiation-induced immunosuppression was investigated. A continuously cultured Candida albicans-specific T-cell line mediated protection of sublethally irradiated mice from disseminated candidiasis as measured by both the fungal load in the kidneys and mortality. These results are the first to demonstrate directly a role for antigen-specific T cells in the protective immune response against murine disseminated candidia...

  14. IL-6 Promotes Cardiac Graft Rejection Mediated by CD4+ Cells1

    OpenAIRE

    Booth, Adam Jared; Grabauskiene, Svetlana; Wood, Sherri Chan; Lu, Guanyi; Burrell, Bryna E.; Bishop, D. Keith

    2011-01-01

    IL-6 mediates numerous immunologic effects relevant to transplant rejection; however its specific contributions to these processes are not fully understood. To this end, we neutralized IL-6 in settings of acute cardiac allograft rejection associated with either CD8+ or CD4+ cell dominant responses. In a setting of CD8+ cell dominant graft rejection, IL-6 neutralization delayed the onset of acute rejection while decreasing graft infiltrate and inverting anti-graft Th1/Th2 priming dominance in ...

  15. Dexamethasone-induced apoptosis of osteocytic and osteoblastic cells is mediated by TAK1 activation.

    Science.gov (United States)

    Ding, Heyuan; Wang, Tao; Xu, Dongli; Cha, Bingbing; Liu, Jun; Li, Yiming

    2015-05-01

    Increased apoptosis of osteoblasts and osteocytes is the main mechanism of glucocorticoid (GC)-induced osteonecrosis. In the current study, we investigated whether dexamethasone (Dex)-induced osteoblastic and osteocytic cell apoptosis is mediated through activation of transforming growth factor-β (TGF-β)-activated kinase 1 (TAK1), and whether TAK1 inhibition could promote survival opposing the deleterious effects of Dex. We found that TAK1 was activated by Dex in both osteocytic MLO-Y4 and osteoblastic OB-6 cells, which was prevented by two known anti-oxidants N-acetylcysteine (NAC) and ebselen. TAK1 inhibitors, including LYTAK1 and 5Z-7-oxozeaenol (57-OZ), inhibited Dex-induced apoptosis of MLO-Y4 and OB-6 cells. Meanwhile shRNA-mediated knockdown of TAK1 also suppressed Dex-induced damages to MLO-Y4 and OB-6 cells. On the other hand, exogenously over-expressing TAK1 enhanced Dex-induced MLO-Y4 and OB-6 cell apoptosis. At the molecular level, we found that TAK1 mediated Dex-induced pro-apoptotic Pyk2-JNK activation. Inhibition or silencing of TAK1 almost abolished Pyk2-JNK phosphorylations by Dex in MLO-Y4 and OB-6 cells. TAK1 over-expression, on the other hand, increased Dex's activity on Pyk2-JNK phosphorylations in above cells. We conclude that part of the pro-apoptotic actions of Dex on osteoblastic and osteocytic cells are mediated through TAK1 activation, and that inhibition of TAK1 might protect from GC-induced damages to osteoblasts and osteocytes. PMID:25753204

  16. Phase 2 Study of Concurrent Cetuximab Plus Definitive Thoracic Radiation Therapy Followed by Consolidation Docetaxel Plus Cetuximab in Poor Prognosis or Elderly Patients With Locally Advanced Non-Small Cell Lung Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Dilling, Thomas J. [Department of Radiation Oncology, Moffitt Cancer Center, Tampa, Florida (United States); Extermann, Martine [Department of Senior Adult Oncology, Moffitt Cancer Center, Tampa, Florida (United States); Kim, Jongphil [Department of Biostatistics and Bioinformatics, Moffitt Cancer Center, Tampa, Florida (United States); Thompson, Lora M. [Department of Supportive Care Medicine, Moffitt Cancer Center, Tampa, Florida (United States); Yue, Binglin [Department of Biostatistics and Bioinformatics, Moffitt Cancer Center, Tampa, Florida (United States); Stevens, Craig W. [Department of Radiation Oncology, Moffitt Cancer Center, Tampa, Florida (United States); Antonia, Scott; Gray, Jhanelle; Williams, Charles; Haura, Eric; Pinder-Schenck, Mary; Tanvetyanon, Tawee [Department of Thoracic Oncology, Moffitt Cancer Center, Tampa, Florida (United States); Kim, Sungjune [Department of Radiation Oncology, Moffitt Cancer Center, Tampa, Florida (United States); Chiappori, Alberto, E-mail: alberto.chiappori@moffitt.org [Department of Thoracic Oncology, Moffitt Cancer Center, Tampa, Florida (United States)

    2014-11-15

    Background: Recursive partitioning analysis has shown that Eastern Cooperative Oncology Group (ECOG) Performance Status (PS) ≥2, male sex, and age ≥70 years are prognostic of poor outcome in locally advanced non-small cell lung cancer (LA-NSCLC) patients. Concurrent chemoradiation therapy (CRT) improves survival, but toxicity is a concern in this frail patient cohort. We therefore opened this trial of concurrent definitive thoracic radiation therapy (XRT) and cetuximab, followed by consolidation docetaxel plus cetuximab. Methods and Materials: Eligible patients had pathologically proven, unresectable LA-NSCLC (stage IIA-“dry” IIIB). They had ECOG PS 2 or weight loss ≥5% in 3 months or were aged ≥70 years. The primary objective was progression-free survival (PFS). Secondary objectives included overall survival (OS) and overall response rate (ORR). Results: From May 2008 to November 2010, a total of 32 patients were evaluated in our single-institution, institutional review board–approved prospective clinical trial. Three patients were screen failures and 2 more withdrew consent before treatment, leaving 27 evaluable patients. One was removed because of poor therapy compliance, and 2 were taken off trial because of grade 3 cetuximab-related toxicities but were followed up under intent-to-treat analysis. The median follow-up and OS were 10.5 months. The median PFS was 7.5 months. The ORR was 59.3%. Eight early/sudden deaths were reported. Upon review, 6 patients developed severe pulmonary complications. Conclusions: Patients enrolled in this trial had improved OS compared with poor-PS historical controls (10.5 vs 6.4 months) and comparable OS to good-PS historical controls (10.5 vs 11.9 months) treated with XRT alone. However, pulmonary toxicity is a concern. Consolidative cetuximab/docetaxel, in conjunction with high-dose radiation therapy, is a putative cause.

  17. Gene expression profiles of human liver cells mediated by hepatitis B virus X protein

    Institute of Scientific and Technical Information of China (English)

    Wei-ying ZHANG; Fu-qing XU; Chang-liang SHAN; Rong XIANG; Li-hong YE; Xiao-dong ZHANG

    2009-01-01

    Aim: To demonstrate the gene expression profiles mediated by hepatitis B virus X protein (HBx), we characterized the molecular features of pathogenesis associated with HBx in a human liver cell model.Methods: We examined gene expression profiles in L-O2-X cells, an engineered L-O2 cell line that constitutively expresses HBx, relative to L-O2 cells using an Agilent 22 K human 70-mer oligonucleotide microarray representing more than 21,329 unique, well-characterized Homo sapiens genes, Western blot analysis and RNA interference (RNAi) targeting HBx mRNA validated the overexpression of proliferating cell nuclear antigen (PCNA) and Bcl-2 in L-O2-X cells. Meanwhile, the BrdU incorporation assay was used to test cell proliferation mediated by upregulated cyclooxygenase-2 (COX-2).Results: The microarray showed that the expression levels of 152 genes were remarkably altered; 82 of the genes were upregulated and 70 genes were downregulated in L-O2-X cells. The altered genes were associated with signal transduction pathways, cell cycle, metastasis, transcriptional regulation, immune response, metabolism, and other processes. PCNA and Bcl-2 were upregulated in L-O2-X cells. Furthermore, we found that COX-2 upregulation in L-O2-X cells enhanced proliferation using the BrdU incorporation assay, whereas indomethacin (an inhibitor of COX-2) abolished the promotion.Conclusion: Our findings provide new evidence that HBx is able to regulate many genes that may be involved in the car-cinogenesis. These regulated genes mediated by HBx may serve as molecular targets for the prevention and treatment of hepatocellular carcinoma.

  18. Expression of Bcl-2 inhibited Fas-mediated apoptosis in human hepatocellular carcinoma BEL-7404 cells

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Apoptosis plays an important role in embryonic development, tissue remodeling, immune regulation and tumor regression. Two groups of molecules (Bcl-2 family and"Death factor"family) are involved in regulating apoptosis. In order to know about the effect of Bcl-2 on apoptosis induced by Fas, a typical member of"Death factor" family, the transfection experiments with expression vectors pcDNA3-fland pcDNA3-bcl-2 were performed in BEL-7404 cells, a human hepatocellular carcinoma cell line which expresses endogenous Fas, but not FasL and Bcl2. The data showed that the expression of FasL in pcDNA3fl transfected hepatoma cells obviously induced the apoptosis of the cells. However, the overexpression of Bcl-2 in pcDNA3bcl-2 transfected 7404/b-16 cells counteracted pcDNA3-fltransient transfection mediated apoptosis. Further study by cotransfection experiments indicated that Bid but not Bax (both were pro-apoptotic proteins of Bcl-2 family) blocked the inhibitory effect of Bcl-2 on Fas-mediated apoptosis. These results suggested that Fas-mediated apoptosis in human hcpatoma cells is possibly regulated by Bcl-2 family proteins via mitochondria pathway.

  19. P-selectin-mediated platelet adhesion promotes the metastasis of murine melanoma cells.

    Directory of Open Access Journals (Sweden)

    Cui-Ling Qi

    Full Text Available Studies have indicated that the aggregation of activated platelets with cancer cells facilitates tumor metastasis; the adhesion molecule P-selectin may be an important mediator of this process, but the detailed mechanism is unclear. In the current study, we established a B16F10 (B16 cell metastatic model in P-selectin knockout (P-sel-/- mice to determine the effect of P-selectin-mediated platelet adhesion on metastasis. Compared with C57 mice, P-sel-/- mice developed fewer metastatic foci, and cell proliferation within the metastatic tumors was inhibited by P-selectin deficiency. The platelet refusion assay demonstrated that mice with P-sel-/- platelets developed fewer lung metastatic foci (P<0.01 with a lower microvascular density (MVD than mice with wild-type platelets. A co-culture model of platelets and B16 cells was utilized to determine the difference in VEGF concentration in the supernatants. The results demonstrated that the supernatant from the P-sel-/- platelet/B16 co-culture had a lower concentration of VEGF. Therefore, our findings indicated that P-selectin deficiency inhibited the metastasis of B16 cells and that wild-type platelet refusion reversed this inhibition. The P-selectin-mediated interaction between platelets and B16 cells promoted angiogenesis by up-regulating VEGF.

  20. Stem cell factor-mediated wild-type KIT receptor activation is critical for gastrointestinal stromal tumor cell growth

    Institute of Scientific and Technical Information of China (English)

    Chen-Guang Bai; Xiao-Wei Hou; Feng Wang; Cen Qiu; Yan Zhu; Ling Huang; Jing Zhao

    2012-01-01

    AIM:To clarify the biological role of stem cell factor (SCF)-mediated wild-type KIT receptor activation in gastrointestinal stromal tumor (GIST) growth.METHODS:The co-expression of wild-type KIT receptor and SCF was evaluated in 51 GIST samples using mutation analysis and immunohistochemistry,and the results were correlated with clinicopathological parameters,including the mitotic count,proliferative index (Ki-67 immunohistochemical staining),mitotic index (phospho-histone H3 immunohistochemical staining)and apoptotic index (terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling).Using primary cultured GIST cells,the effect of SCF-mediated wild-type KIT receptor activation was determined by western blotting,methyl thiazolyl tetrazolium (MTT),and apoptosis assays.RESULTS:We found that wild-type KIT receptor and SCF protein were expressed in 100% and 76.5% of the 51 GIST samples,respectively,and the co-expression of wild-type KIT receptor and SCF was associated with known indicators of poor prognosis,including larger tumor size (P =0.0118),higher mitotic count (P =0.0058),higher proliferative index (P =0.0012),higher mitotic index (P =0.0282),lower apoptosis index (P =0.0484),and increased National Institutes of Health risk level (P =0.0012).We also found that the introduction of exogenous SCF potently increased KIT kinase activity,stimulated cell proliferation (P < 0.01) and inhibited apoptosis (P < 0.01) induced by serum starvation,while a KIT immunoblocking antibody suppressed proliferation (P =0.01) and promoted apoptosis (P < 0.01)in cultured GIST cells.CONCLUSION:SCF-mediated wild-type KIT receptor activation plays an important role in GIST cell growth.The inhibition of SCF-mediated wild-type KIT receptor activation may prove to be particularly important for GIST therapy.

  1. CD47-signal regulatory protein-alpha (SIRP alpha) interactions form a barrier for antibody-mediated tumor cell destruction

    NARCIS (Netherlands)

    Zhao, Xi Wen; van Beek, Ellen M.; Schornagel, Karin; Van der Maaden, Hans; Van Houdt, Michel; Otten, Marielle A.; Finetti, Pascal; Van Egmond, Marjolein; Matozaki, Takashi; Kraal, Georg; Birnbaum, Daniel; van Elsas, Andrea; Kuijpers, Taco W.; Bertucci, Francois; van den Berg, Timo K.

    2011-01-01

    Monoclonal antibodies are among the most promising therapeutic agents for treating cancer. Therapeutic cancer antibodies bind to tumor cells, turning them into targets for immune-mediated destruction. We show here that this antibody-mediated killing of tumor cells is limited by a mechanism involving

  2. Adenovirus-mediated CTLA4Ig gene inhibits infiltration of immune cells and cell apoptosis in rats after liver transplantation

    Institute of Scientific and Technical Information of China (English)

    Guo-Ping Jiang; Zhen-Hua Hu; Shu-Sen Zheng; Chang-Ku Jia; Ai-Bin Zhang; Wei-Lin Wang

    2005-01-01

    AIM: To investigate the role of adenovirus-mediated CTLA4Ig gene therapy in inhibiting the infiltration of macrophages and CD8+T cells and cell apoptosis after liver transplantation.METHODS: The rat orthotopic liver transplantation model was applied. The rats were divided into three groups:group Ⅰ: rejection control (SD-to-Wistar); group Ⅱ: acute rejection treated with intramuscular injection of CsA injection of 1× 109 PFU adenovirus-mediated CTLA4Ig gene liquor in dorsal vein of penis 7 d before liver transplantation(SD-to-Wistar+CTLA4Ig). Immunohistochemistry and transferase-mediated dUTPnick-end labeling (TUNEL)were used to analyze the expression of CTLA4Ig gene in liver, infiltration of macrophages and CD8+T cells, cell apoptosis in grafts at different time-points after liver transplantation. Histopathological examination was done.RESULTS: CTLA4Ig gene expression was positive in liver on d 7 after administering adenovirus-mediated CTLA4Ig gene via vein, and remained positive until day 60 after liver transplantation. Infiltration of macrophages and CD8+T cells in CTLA4Ig-treated group was less than in rejection control group and CsA-treated group. The apoptotic index of rejection group on d 3, 5, and 7 were significantly higher than that of CTLA4Ig-treated group. A good correlation was found between severity of rejection reaction and infiltration of immune activator cells or cell apoptotic index in grafts.CONCLUSION: CTLA4Ig gene is constantly expressed in liver and plays an important role in inducing immune tolerance.

  3. Methoxychlor enhances degranulation of murine mast cells by regulating FcεRI-mediated signal transduction.

    Science.gov (United States)

    Yasunaga, Sho; Nishi, Kosuke; Nishimoto, Sogo; Sugahara, Takuya

    2015-01-01

    Methoxychlor, an organochlorine insecticide developed to replace DDT (dichlorodiphenyltrichloroethane), has been reported to induce mast cell degranulation and to enhance IgE-mediated allergic responses. However, the mechanisms underlying these effects are not clear. To clarify potential mechanisms, the effects of methoxychlor on degranulation of mast cells were examined. Degranulation responses were evaluated using RBL-2H3 cells and mouse bone marrow-derived mast cells with either the antigen-induced or calcium ionophore-induced stimulation. Phosphorylation of enzymes related to signaling events associated with mast cell degranulation was analyzed by immunoblotting. Effects on vascular permeability in the passive cutaneous anaphylaxis reaction were evaluated following oral administration of methoxychlor to BALB/c mice. The results indicated that methoxychlor caused increased mast cell degranulation in the presence of antigen, whereas it had no effect on calcium ionophore-induced degranulation of RBL-2H3 cells. Immunoblot analyses demonstrated that the phosphorylation level of phosphoinositide 3-kinase (which plays a central role in mast cell signaling) was increased by methoxychlor during antigen-induced degranulation. In addition, methoxychlor activated the signaling pathway via the high-affinity IgE receptor by inducing phosphorylation of Syk and PLCγ1/2, which transfer the signal for degranulation downstream. Lastly, oral administration of methoxychlor exhibited a tendency to promote vascular permeability in passive cutaneous anaphylaxis model mice. Taken together, the results here suggested that methoxychlor enhanced degranulation through FcεRI-mediated signaling and promoted allergenic symptoms involved in mast cell degranulation.

  4. Ferulic acid reverses ABCB1-mediated paclitaxel resistance in MDR cell lines.

    Science.gov (United States)

    Muthusamy, Ganesan; Balupillai, Agilan; Ramasamy, Karthikeyan; Shanmugam, Mohana; Gunaseelan, Srithar; Mary, Beaulah; Prasad, N Rajendra

    2016-09-01

    Multidrug resistance (MDR) remains a major obstacle in cancer chemotherapy. The use of the dietary phytochemicals as chemosensitizing agents to enhance the efficacy of conventional cytostatic drugs has recently gained the attention as a plausible approach for overcoming the drug resistance. The aim of this study was to investigate whether a naturally occurring diet-based phenolic acid, ferulic acid, could sensitize paclitaxel efficacy in ABCB1 overexpressing (P-glycoprotein) colchicine selected KB Ch(R)8-5 cell line. In vitro drug efflux assays demonstrated that ferulic acid inhibits P-glycoprotein transport function in drug resistant KB Ch(R)8-5 cell lines. However, ferulic acid significantly downregulates ABCB1 expression in a concentration dependent manner. Cytotoxicity assay reveals that ferulic acid decreased paclitaxel resistance in KBCh(R)8-5 and HEK293/ABCB1 cells, which indicates its chemosensitizing potential. Clonogenic cell survival assay and apoptotic morphological staining further confirm the chemosensitizing potential of ferulic acid in drug resistant KB Ch(R)8-5 cell lines. Ferulic acid treatment enhances paclitaxel mediated cell cycle arrest and upregulates paclitaxel-induced apoptotic signaling in KB resistant cells. Hence, it has been concluded that downregulation of ABCB1 and subsequent induction of paclitaxel-mediated cell cycle arrest and apoptotic signaling may be the cause for the chemosensitizing potential of ferulic acid in P-gp overexpressing cell lines. PMID:27262378

  5. A RUNX2-Mediated Epigenetic Regulation of the Survival of p53 Defective Cancer Cells.

    Directory of Open Access Journals (Sweden)

    Min Hwa Shin

    2016-02-01

    Full Text Available The inactivation of p53 creates a major challenge for inducing apoptosis in cancer cells. An attractive strategy is to identify and subsequently target the survival signals in p53 defective cancer cells. Here we uncover a RUNX2-mediated survival signal in p53 defective cancer cells. The inhibition of this signal induces apoptosis in cancer cells but not non-transformed cells. Using the CRISPR technology, we demonstrate that p53 loss enhances the apoptosis caused by RUNX2 knockdown. Mechanistically, RUNX2 provides the survival signal partially through inducing MYC transcription. Cancer cells have high levels of activating histone marks on the MYC locus and concomitant high MYC expression. RUNX2 knockdown decreases the levels of these histone modifications and the recruitment of the Menin/MLL1 (mixed lineage leukemia 1 complex to the MYC locus. Two inhibitors of the Menin/MLL1 complex induce apoptosis in p53 defective cancer cells. Together, we identify a RUNX2-mediated epigenetic mechanism of the survival of p53 defective cancer cells and provide a proof-of-principle that the inhibition of this epigenetic axis is a promising strategy to kill p53 defective cancer cells.

  6. Identification of Mediator Kinase Substrates in Human Cells using Cortistatin A and Quantitative Phosphoproteomics.

    Science.gov (United States)

    Poss, Zachary C; Ebmeier, Christopher C; Odell, Aaron T; Tangpeerachaikul, Anupong; Lee, Thomas; Pelish, Henry E; Shair, Matthew D; Dowell, Robin D; Old, William M; Taatjes, Dylan J

    2016-04-12

    Cortistatin A (CA) is a highly selective inhibitor of the Mediator kinases CDK8 and CDK19. Using CA, we now report a large-scale identification of Mediator kinase substrates in human cells (HCT116). We identified over 16,000 quantified phosphosites including 78 high-confidence Mediator kinase targets within 64 proteins, including DNA-binding transcription factors and proteins associated with chromatin, DNA repair, and RNA polymerase II. Although RNA-seq data correlated with Mediator kinase targets, the effects of CA on gene expression were limited and distinct from CDK8 or CDK19 knockdown. Quantitative proteome analyses, tracking around 7,000 proteins across six time points (0-24 hr), revealed that CA selectively affected pathways implicated in inflammation, growth, and metabolic regulation. Contrary to expectations, increased turnover of Mediator kinase targets was not generally observed. Collectively, these data support Mediator kinases as regulators of chromatin and RNA polymerase II activity and suggest their roles extend beyond transcription to metabolism and DNA repair. PMID:27050516

  7. Identification of Mediator Kinase Substrates in Human Cells using Cortistatin A and Quantitative Phosphoproteomics

    Directory of Open Access Journals (Sweden)

    Zachary C. Poss

    2016-04-01

    Full Text Available Cortistatin A (CA is a highly selective inhibitor of the Mediator kinases CDK8 and CDK19. Using CA, we now report a large-scale identification of Mediator kinase substrates in human cells (HCT116. We identified over 16,000 quantified phosphosites including 78 high-confidence Mediator kinase targets within 64 proteins, including DNA-binding transcription factors and proteins associated with chromatin, DNA repair, and RNA polymerase II. Although RNA-seq data correlated with Mediator kinase targets, the effects of CA on gene expression were limited and distinct from CDK8 or CDK19 knockdown. Quantitative proteome analyses, tracking around 7,000 proteins across six time points (0–24 hr, revealed that CA selectively affected pathways implicated in inflammation, growth, and metabolic regulation. Contrary to expectations, increased turnover of Mediator kinase targets was not generally observed. Collectively, these data support Mediator kinases as regulators of chromatin and RNA polymerase II activity and suggest their roles extend beyond transcription to metabolism and DNA repair.

  8. LPS-TLR4 Pathway Mediates Ductular Cell Expansion in Alcoholic Hepatitis

    Science.gov (United States)

    Odena, Gemma; Chen, Jiegen; Lozano, Juan Jose; Altamirano, Jose; Rodrigo-Torres, Daniel; Affo, Silvia; Morales-Ibanez, Oriol; Matsushita, Hiroshi; Zou, Jian; Dumitru, Raluca; Caballeria, Juan; Gines, Pere; Arroyo, Vicente; You, Min; Rautou, Pierre-Emmanuel; Valla, Dominique; Crews, Fulton; Seki, Ekihiro; Sancho-Bru, Pau; Bataller, Ramon

    2016-01-01

    Alcoholic hepatitis (AH) is the most severe form of alcoholic liver disease for which there are no effective therapies. Patients with AH show impaired hepatocyte proliferation, expansion of inefficient ductular cells and high lipopolysaccharide (LPS) levels. It is unknown whether LPS mediates ductular cell expansion. We performed transcriptome studies and identified keratin 23 (KRT23) as a new ductular cell marker. KRT23 expression correlated with mortality and LPS serum levels. LPS-TLR4 pathway role in ductular cell expansion was assessed in human and mouse progenitor cells, liver slices and liver injured TLR4 KO mice. In AH patients, ductular cell expansion correlated with portal hypertension and collagen expression. Functional studies in ductular cells showed that KRT23 regulates collagen expression. These results support a role for LPS-TLR4 pathway in promoting ductular reaction in AH. Maneuvers aimed at decreasing LPS serum levels in AH patients could have beneficial effects by preventing ductular reaction development. PMID:27752144

  9. Bam32: a novel mediator of Erk activation in T cells.

    Science.gov (United States)

    Sommers, Connie L; Gurson, Jordan M; Surana, Rishi; Barda-Saad, Mira; Lee, Jan; Kishor, Aparna; Li, Wenmei; Gasser, Adam J; Barr, Valarie A; Miyaji, Michihiko; Love, Paul E; Samelson, Lawrence E

    2008-07-01

    Bam32 (B lymphocyte adapter molecule of 32 kDa) is an adapter protein expressed in some hematopoietic cells including B and T lymphocytes. It was previously shown that Bam32-deficient mice have defects in various aspects of B cell activation including B cell receptor (BCR)-induced Erk activation, BCR-induced proliferation and T-independent antibody responses. In this study, we have examined the role of Bam32 in T cell activation using Bam32-deficient mice. By comparing CD4(+) T cells from lymph nodes of wild-type and Bam32-deficient mice, we found that Bam32 was required for optimal TCR-induced Erk activation, cytokine production, proliferation and actin-mediated spreading of CD4(+) T cells. These results indicate a novel pathway to Erk activation in T cells involving the adapter protein Bam32.

  10. Polyphosphate induces matrix metalloproteinase-3-mediated proliferation of odontoblast-like cells derived from induced pluripotent stem cells

    International Nuclear Information System (INIS)

    Inorganic polyphosphate [Poly(P)] may represent a physiological source of phosphate and has the ability to induce bone differentiation in osteoblasts. We previously reported that cytokine-induced matrix metalloproteinase (MMP)-3 accelerates the proliferation of purified odontoblast-like cells. In this study, MMP-3 small interfering RNA (siRNA) was transfected into odontoblast-like cells derived from induced pluripotent stem cells to investigate whether MMP-3 activity is induced by Poly(P) and/or is associated with cell proliferation and differentiation into odontoblast-like cells. Treatment with Poly(P) led to an increase in both cell proliferation and additional odontoblastic differentiation. Poly(P)-treated cells showed a small but significant increase in dentin sialophosphoprotein (DSPP) and dentin matrix protein-1 (DMP-1) mRNA expression, which are markers of mature odontoblasts. The cells also acquired additional odontoblast-specific properties including adoption of an odontoblastic phenotype typified by high alkaline phosphatase (ALP) activity and a calcification capacity. In addition, Poly(P) induced expression of MMP-3 mRNA and protein, and increased MMP-3 activity. MMP-3 siRNA-mediated disruption of the expression of these effectors potently suppressed the expression of odontoblastic biomarkers ALP, DSPP, and DMP-1, and blocked calcification. Interestingly, upon siRNA-mediated silencing of MMP-3, we noted a potent and significant decrease in cell proliferation. Using specific siRNAs, we revealed that a unique signaling cascade, Poly(P)→MMP-3→DSPP and/or DMP-1, was intimately involved in the proliferation of odontoblast-like cells. - Highlights: • Polyphosphate increases proliferation of iPS cell-derived odontoblast-like cells. • Polyphosphate-induced MMP-3 results in an increase of cell proliferation. • Induced cell proliferation involves MMP-3, DSPP, and/or DMP-1 sequentially. • Induced MMP-3 also results in an increase of odontoblastic

  11. Polyphosphate induces matrix metalloproteinase-3-mediated proliferation of odontoblast-like cells derived from induced pluripotent stem cells

    Energy Technology Data Exchange (ETDEWEB)

    Ozeki, Nobuaki; Hase, Naoko; Yamaguchi, Hideyuki; Hiyama, Taiki; Kawai, Rie [Department of Endodontics, School of Dentistry, Aichi Gakuin University, 2-11 Suemori-dori, Chikusa-ku, Nagoya, Aichi 464-8651 (Japan); Kondo, Ayami [Department of Medicinal Biochemistry, School of Pharmacy, Aichi Gakuin University, 1-100 Kusumoto, Chikusa-ku, Nagoya 464-8650 (Japan); Nakata, Kazuhiko [Department of Endodontics, School of Dentistry, Aichi Gakuin University, 2-11 Suemori-dori, Chikusa-ku, Nagoya, Aichi 464-8651 (Japan); Mogi, Makio, E-mail: makio@dpc.agu.ac.jp [Department of Medicinal Biochemistry, School of Pharmacy, Aichi Gakuin University, 1-100 Kusumoto, Chikusa-ku, Nagoya 464-8650 (Japan)

    2015-05-01

    Inorganic polyphosphate [Poly(P)] may represent a physiological source of phosphate and has the ability to induce bone differentiation in osteoblasts. We previously reported that cytokine-induced matrix metalloproteinase (MMP)-3 accelerates the proliferation of purified odontoblast-like cells. In this study, MMP-3 small interfering RNA (siRNA) was transfected into odontoblast-like cells derived from induced pluripotent stem cells to investigate whether MMP-3 activity is induced by Poly(P) and/or is associated with cell proliferation and differentiation into odontoblast-like cells. Treatment with Poly(P) led to an increase in both cell proliferation and additional odontoblastic differentiation. Poly(P)-treated cells showed a small but significant increase in dentin sialophosphoprotein (DSPP) and dentin matrix protein-1 (DMP-1) mRNA expression, which are markers of mature odontoblasts. The cells also acquired additional odontoblast-specific properties including adoption of an odontoblastic phenotype typified by high alkaline phosphatase (ALP) activity and a calcification capacity. In addition, Poly(P) induced expression of MMP-3 mRNA and protein, and increased MMP-3 activity. MMP-3 siRNA-mediated disruption of the expression of these effectors potently suppressed the expression of odontoblastic biomarkers ALP, DSPP, and DMP-1, and blocked calcification. Interestingly, upon siRNA-mediated silencing of MMP-3, we noted a potent and significant decrease in cell proliferation. Using specific siRNAs, we revealed that a unique signaling cascade, Poly(P)→MMP-3→DSPP and/or DMP-1, was intimately involved in the proliferation of odontoblast-like cells. - Highlights: • Polyphosphate increases proliferation of iPS cell-derived odontoblast-like cells. • Polyphosphate-induced MMP-3 results in an increase of cell proliferation. • Induced cell proliferation involves MMP-3, DSPP, and/or DMP-1 sequentially. • Induced MMP-3 also results in an increase of odontoblastic

  12. CD11c⁺ cells partially mediate the renoprotective effect induced by bone marrow-derived mesenchymal stem cells.

    Directory of Open Access Journals (Sweden)

    Myung-Gyu Kim

    Full Text Available Previous studies have shown that induction of immune tolerance by mesenchymal stem cells (MSCs is partially mediated via monocytes or dendritic cells (DCs. The purpose of this study was to determine the role of CD11c⁺ cells in MSC-induced effects on ischemia/reperfusion injury (IRI. IRI was induced in wildtype (WT mice and CD11c⁺-depleted mice following pretreatment with or without MSCs. In the in-vitro experiments, the MSC-treated CD11c⁺ cells acquired regulatory phenotype with increased intracellular IL-10 production. Although splenocytes cocultured with MSCs showed reduced T cell proliferation and expansion of CD4⁺FoxP3⁺ regulatory T cells (Tregs, depletion of CD11c⁺ cells was associated with partial loss of MSCs effect on T cells. In in-vivo experiment, MSCs' renoprotective effect was also associated with induction of more immature CD11c⁺ cells and increased FoxP3 expression in I/R kidneys. However all these effects induced by the MSCs were partially abrogated when CD11c⁺ cells were depleted in the CD11c⁺-DTR transgenic mice. In addition, the observation that adoptive transfer of WT CD11c⁺ cells partially restored the beneficial effect of the MSCs, while transferring IL-10 deficient CD11c⁺ cells did not, strongly suggest the important contribution of IL-10 producing CD11c⁺ cells in attenuating kidney injury by MSCs. Our results suggest that the CD11c⁺ cell-Tregs play critical role in mediating renoprotective effect of MSCs.

  13. Bone marrow-derived mesenchymal stromal cells inhibit Th2-mediated allergic airways inflammation in mice.

    Science.gov (United States)

    Goodwin, Meagan; Sueblinvong, Viranuj; Eisenhauer, Philip; Ziats, Nicholas P; LeClair, Laurie; Poynter, Matthew E; Steele, Chad; Rincon, Mercedes; Weiss, Daniel J

    2011-07-01

    Bone marrow-derived mesenchymal stromal cells (BMSCs) mitigate inflammation in mouse models of acute lung injury. However, specific mechanisms of BMSC actions on CD4 T lymphocyte-mediated inflammation in vivo remain poorly understood. Limited data suggests promotion of Th2 phenotype in models of Th1-mediated diseases. However, whether this might alleviate or worsen Th2-mediated diseases such as allergic asthma is unknown. To ascertain the effects of systemic administration of BMSCs in a mouse model of Th2-mediated allergic airways inflammation, ovalbumin (OVA)-induced allergic airways inflammation was induced in wild-type C57BL/6 and BALB/c mice as well as in interferon-γ (IFNγ) receptor null mice. Effects of systemic administration during antigen sensitization of either syngeneic or allogeneic BMSC on airways hyperreactivity, lung inflammation, antigen-specific CD4 T lymphocytes, and serum immunoglobulins were assessed. Both syngeneic and allogeneic BMSCs inhibited airways hyperreactivity and lung inflammation through a mechanism partly dependent on IFNγ. However, contrary to existing data, BMSCs did not affect antigen-specific CD4 T lymphocyte proliferation but rather promoted Th1 phenotype in vivo as assessed by both OVA-specific CD4 T lymphocyte cytokine production and OVA-specific circulating immunoglobulins. BMSCs treated to prevent release of soluble mediators and a control cell population of primary dermal skin fibroblasts only partly mimicked the BMSC effects and in some cases worsened inflammation. In conclusion, BMSCs inhibit Th2-mediated allergic airways inflammation by influencing antigen-specific CD4 T lymphocyte differentiation. Promotion of a Th1 phenotype in antigen-specific CD4 T lymphocytes by BMSCs is sufficient to inhibit Th2-mediated allergic airways inflammation through an IFNγ-dependent process. PMID:21544902

  14. Heterotrimeric G-protein is involved in phytochrome A-mediated cell death of Arabidopsis hypocotyls

    Institute of Scientific and Technical Information of China (English)

    Qing Wei; Wenbin Zhou; Guangzhen Hu; Jiamian Wei; Hongquan Yang; Jirong Huang

    2008-01-01

    The heterotrimeric guanine nucleotide-binding protein (G-protein) has been demonstrated to mediate various signaling pathways in plants. However,its role in phytochrome A (phyA) signaling remains elusive. In this study,we discover a new phyA-mediated phenotype designated far-red irradiation (FR) preconditioned cell death,which occurs only in the hypocotyls of FR-grown seedlings following exposure to white light (WL). The cell death is mitigated in the Ga mutant gpal but aggravated in the Gβ mutant agbl in comparison with the wild type (WT),indicative of antagonistic roles of GPAI and AGB1 in the phyA-mediated cell-death pathway. Further investigation indicates that FR-induced accumulation of nonphotoconvertible protochlorophyllide (Pchlide633),which generates reactive oxygen species (ROS)on exposure to WL,is required for FR-preconditioned cell death. Moreover,ROS is mainly detected in chloroplasts using the fluorescent probe. Interestingly,the application of H2O2 to dark-grown seedlings results in a phenotype similar to FR-preconditioned cell death. This reveals that ROS is a critical mediator for the cell death. In addition,we observe that agbl is more sensitive to H2O2 than WT seedlings,indicating that the G-protein may also modify the sensitivity of the seedlings to ROS stress. Taking these results together,we infer that the G-protein may be involved in the phyA signaling pathway to regulate FR-preconditioned cell death of Arabidopsis hypocotyls.Apossible mechanism underlying the involvement of the G-protein in phyA signaling is discussed in this study.

  15. Sphingosine-1-phosphate mediates epidermal growth factor-induced muscle satellite cell activation

    Energy Technology Data Exchange (ETDEWEB)

    Nagata, Yosuke, E-mail: cynagata@mail.ecc.u-tokyo.ac.jp; Ohashi, Kazuya; Wada, Eiji; Yuasa, Yuki; Shiozuka, Masataka; Nonomura, Yoshiaki; Matsuda, Ryoichi

    2014-08-01

    Skeletal muscle can regenerate repeatedly due to the presence of resident stem cells, called satellite cells. Because satellite cells are usually quiescent, they must be activated before participating in muscle regeneration in response to stimuli such as injury, overloading, and stretch. Although satellite cell activation is a crucial step in muscle regeneration, little is known of the molecular mechanisms controlling this process. Recent work showed that the bioactive lipid sphingosine-1-phosphate (S1P) plays crucial roles in the activation, proliferation, and differentiation of muscle satellite cells. We investigated the role of growth factors in S1P-mediated satellite cell activation. We found that epidermal growth factor (EGF) in combination with insulin induced proliferation of quiescent undifferentiated mouse myoblast C2C12 cells, which are also known as reserve cells, in serum-free conditions. Sphingosine kinase activity increased when reserve cells were stimulated with EGF. Treatment of reserve cells with the D-erythro-N,N-dimethylsphingosine, Sphingosine Kinase Inhibitor, or siRNA duplexes specific for sphingosine kinase 1, suppressed EGF-induced C2C12 activation. We also present the evidence showing the S1P receptor S1P2 is involved in EGF-induced reserve cell activation. Moreover, we demonstrated a combination of insulin and EGF promoted activation of satellite cells on single myofibers in a manner dependent on SPHK and S1P2. Taken together, our observations show that EGF-induced satellite cell activation is mediated by S1P and its receptor. - Highlights: • EGF in combination with insulin induces proliferation of quiescent C2C12 cells. • Sphingosine kinase activity increases when reserve cells are stimulated with EGF. • EGF-induced activation of reserve cells is dependent on sphingosine kinase and ERK. • The S1P receptor S1P2 is involved in EGF-induced reserve cell activation. • EGF-induced reserve cell activation is mediated by S1P and its

  16. School Consolidation: Easing the Transition. Administrative Report.

    Science.gov (United States)

    Moray, Mary

    Changing population patterns, inflated housing costs, and cuts in school financing have forced many school districts to face school closures and school consolidation as a way of maintaining solvency. This report reviews the literature on school consolidation with attention to the fact that the need to consolidate now faces elementary schools as…

  17. Consolidation of Sensorimotor Learning during Sleep

    Science.gov (United States)

    Brawn, Timothy P.; Fenn, Kimberly M.; Nusbaum, Howard C.; Margoliash, Daniel

    2008-01-01

    Consolidation of nondeclarative memory is widely believed to benefit from sleep. However, evidence is mainly limited to tasks involving rote learning of the same stimulus or behavior, and recent findings have questioned the extent of sleep-dependent consolidation. We demonstrate consolidation during sleep for a multimodal sensorimotor skill that…

  18. Impact Mediated Loading Cytoplasmic Loading of Macromolecules into Adherent Cells

    Science.gov (United States)

    Clarke, Mark S. F.; Feeback, Daniel L.; Vanderburg, Charles R.

    2003-01-01

    The advent of modern molecular biology, including the development of gene array technologies, has resulted in an explosion of information concerning the specific genes activated during normal cellular development, as well as those associated with a variety of pathological conditions. These techniques have served as a highly efficient, broacI.-based screening approach for those specific genes involved. in regulating normal cellular physiology and identifying candidate genes directly associated with the etiology of specific disease states. However, this approach provides information at the transcriptional' level only and does not necessarily indicate . that the gene in question is in fact translated ito a protein, or whether or not post-translational modification of the protein occurs. The critical importance of post-translational modification (i.e. phosphorylation, glycosylation, sialyation, etc.) to protein function has been recognized with regard to a number of proteins involved in a variety of important disease states. For example, altered glycosylation of beta-amyloid precursor protein results in an increase in the amount of beta-amyloid peptide generated and hence secreted as insoluble extracellular amyloid deposits (Georgopoulou, McLaughlin et al. 2001; Walter, Fluhrer et al. 2001), a pathological hal1nark of Alzheimer's disease. Abnormal phosphorylaion of synapsin I has been linked to alterations in synaptic vesicle trafficking leading to defective neurotransmission in Huntington's disease (Lievens, Woodman et al. 2002). Altered phosphorylation of the TAU protein involved in microtubule function has been linked to a number of neurodegenative diseases such as Alzheimer's disease (Billingsley and Kincaid 1997; Sanchez, Alvarez-Tllada et a1. 2001). Aberrant siaIyation of cell/I surface antigens has been detected in a number of different tumor cell types and has been linked to the acquisition of a neoplastic phenotype (Sell 1990), while improper' sia1yation of

  19. Consolidated results 2000. Forecasts 2001; Resultats consolides 2000. Perspectives 2001

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-07-01

    This document presents an economic analysis of the Group Gaz De France consolidated results for the year 2000. The main topics are the evolution of the energy market, the great economic growth for the five businesses of the Group (exploration-production, trade, transport, distribution and services), financial results affected by the supply costs increase, the position reinforcement among the gas leaders in Europe and the highlights of 2000. (A.L.B.)

  20. The pan-ErbB tyrosine kinase inhibitor canertinib induces caspase-mediated cell death in human T-cell leukemia (Jurkat) cells

    Energy Technology Data Exchange (ETDEWEB)

    Trinks, Cecilia, E-mail: Cecilia.trinks@liu.se [Division of Oncology, Department of Clinical and Experimental Medicine, Faculty of Health Sciences, Linkoeping University, Linkoeping (Sweden); Severinsson, Emelie A., E-mail: Emelie.severinsson@liu.se [Division of Oncology, Department of Clinical and Experimental Medicine, Faculty of Health Sciences, Linkoeping University, Linkoeping (Sweden); Holmlund, Birgitta, E-mail: Birgitta.holmlund@lio.se [Department of Oncology, County Council of Ostergoetland, Linkoeping (Sweden); Green, Anna, E-mail: Anna.green@liu.se [Division of Cell Biology, Department of Clinical and Experimental Medicine, Faculty of Health Sciences, Linkoeping University, Linkoeping (Sweden); Green, Henrik, E-mail: Henrik.green@liu.se [Clinical Pharmacology, Division of Drug Research, Department of Medical and Health Sciences, Faculty of Health Sciences, Linkoeping University, Linkoeping (Sweden); Joensson, Jan-Ingvar, E-mail: Jan-ingvar.jonsson@liu.se [Experimental Hematology Unit, Department of Clinical and Experimental Medicine, Faculty of Health Sciences, Linkoeping University, Linkoeping (Sweden); Hallbeck, Anna-Lotta, E-mail: Anna-Lotta.Hallbeck@lio.se [Division of Oncology, Department of Clinical and Experimental Medicine, Faculty of Health Sciences, Linkoeping University, Linkoeping (Sweden); Department of Oncology, County Council of Ostergoetland, Linkoeping (Sweden); Walz, Thomas M., E-mail: Thomas.Walz@lio.se [Division of Oncology, Department of Clinical and Experimental Medicine, Faculty of Health Sciences, Linkoeping University, Linkoeping (Sweden); Department of Oncology, County Council of Ostergoetland, Linkoeping (Sweden)

    2011-07-08

    Highlights: {yields} Canertinib induces caspase-mediated apoptosis in T-cell leukemia cells in vitro. {yields} Canertinib mediates activation of the intrinsic apoptotic pathway. {yields} Canertinib induces apoptosis in an ErbB receptor independent manner. {yields} Lymphocyte specific proteins as well as survival kinases are inhibited. {yields} Canertinib may act as a multi-kinase inhibiting drug in human T-cell malignancies. -- Abstract: Canertinib is a novel ErbB-receptor inhibitor currently in clinical development for the treatment of solid tumors overexpressing ErbB-receptors. We have recently demonstrated that canertinib displays anti-proliferative and pro-apoptotic effects in human myeloid leukemia cells devoid of ErbB-receptors. The mechanism mediating these effects are however unknown. In this study, we show that canertinib is able to act as a multi-kinase inhibitor by inhibition of several intracellular kinases involved in T-cell signaling such as Akt, Erk1/2 and Zap-70, and reduced Lck protein expression in the human T-cell leukemia cell line Jurkat. Treatment with canertinib at a concentration of 2 {mu}M caused accumulation of Jurkat cells in the G{sub 1} cell cycle phase and increased doses induced apoptosis in a time-dependent manner. Apoptotic signs of treated cells were detected by Annexin V staining and cleavage of PARP, caspase-3, -8, -9, -10 and Bid. A subset of the pro-apoptotic signals mediated by canertinib could be significantly reduced by specific caspase inhibitors. Taken together, these results demonstrate the dual ability of canertinib to downregulate important signaling pathways and to activate caspase-mediated intrinsic apoptosis pathway in human T-cell leukemia cells.

  1. GABAA Receptor Blockade Enhances Memory Consolidation by Increasing Hippocampal BDNF Levels

    OpenAIRE

    Kim, Dong hyun; Kim, Jong Min; Park, Se Jin; Cai, MuDan; Liu, Xiaotong; Lee, Seungheon; Shin, Chan Young; Ryu, Jong Hoon

    2011-01-01

    Memory consolidation is the process by which acquired information is converted to something concrete to be retrieved later. Here we examined a potential role for brain-derived neurotrophic factor (BDNF) in mediating the enhanced memory consolidation induced by the GABAA receptor antagonist, bicuculline methiodide. With the administration of an acquisition trial in naïve mice using a passive avoidance task, mature BDNF (mBDNF) levels were temporally changed in the hippocampal CA1 region, and t...

  2. The Growing Complexity of Cancer Cell Response to DNA-Damaging Agents: Caspase 3 Mediates Cell Death or Survival?

    Science.gov (United States)

    Mirzayans, Razmik; Andrais, Bonnie; Kumar, Piyush; Murray, David

    2016-05-11

    It is widely stated that wild-type p53 either mediates the activation of cell cycle checkpoints to facilitate DNA repair and promote cell survival, or orchestrates apoptotic cell death following exposure to cancer therapeutic agents. This reigning paradigm has been challenged by numerous discoveries with different human cell types, including solid tumor-derived cell lines. Thus, activation of the p53 signaling pathway by ionizing radiation and other DNA-damaging agents hinders apoptosis and triggers growth arrest (e.g., through premature senescence) in some genetic backgrounds; such growth arrested cells remain viable, secrete growth-promoting factors, and give rise to progeny with stem cell-like properties. In addition, caspase 3, which is best known for its role in the execution phase of apoptosis, has been recently reported to facilitate (rather than suppress) DNA damage-induced genomic instability and carcinogenesis. This observation is consistent with an earlier report demonstrating that caspase 3 mediates secretion of the pro-survival factor prostaglandin E₂, which in turn promotes enrichment of tumor repopulating cells. In this article, we review these and related discoveries and point out novel cancer therapeutic strategies. One of our objectives is to demonstrate the growing complexity of the DNA damage response beyond the conventional "repair and survive, or die" hypothesis.

  3. RNA interference mediated inhibition of dengue virus multiplication and entry in HepG2 cells.

    Directory of Open Access Journals (Sweden)

    Mohammed Abdelfatah Alhoot

    Full Text Available BACKGROUND: Dengue virus-host cell interaction initiates when the virus binds to the attachment receptors followed by endocytic internalization of the virus particle. Successful entry into the cell is necessary for infection initiation. Currently, there is no protective vaccine or antiviral treatment for dengue infection. Targeting the viral entry pathway has become an attractive therapeutic strategy to block infection. This study aimed to investigate the effect of silencing the GRP78 and clathrin-mediated endocytosis on dengue virus entry and multiplication into HepG2 cells. METHODOLOGY/PRINCIPAL FINDINGS: HepG2 cells were transfected using specific siRNAs to silence the cellular surface receptor (GRP78 and clathrin-mediated endocytosis pathway. Gene expression analysis showed a marked down-regulation of the targeted genes (87.2%, 90.3%, and 87.8% for GRP78, CLTC, and DNM2 respectively in transfected HepG2 cells when measured by RT-qPCR. Intracellular and extracellular viral RNA loads were quantified by RT-qPCR to investigate the effect of silencing the attachment receptor and clathrin-mediated endocytosis on dengue virus entry. Silenced cells showed a significant reduction of intracellular (92.4% and extracellular viral RNA load (71.4% compared to non-silenced cells. Flow cytometry analysis showed a marked reduction of infected cells (89.7% in silenced HepG2 cells compared to non-silenced cells. Furthermore, the ability to generate infectious virions using the plaque assay was reduced 1.07 log in silenced HepG2 cells. CONCLUSIONS/SIGNIFICANCE: Silencing the attachment receptor and clathrin-mediated endocytosis using siRNA could inhibit dengue virus entry and multiplication into HepG2 cells. This leads to reduction of infected cells as well as the viral load, which might function as a unique and promising therapeutic agent for attenuating dengue infection and prevent the development of dengue fever to the severe life-threatening DHF or DSS

  4. Polyunsaturated fatty acid-derived lipid mediators and T cell function

    Directory of Open Access Journals (Sweden)

    Anna eNicolaou

    2014-02-01

    Full Text Available Fatty acids are involved in T cell biology both as nutrients important for energy production as well as signalling molecules. In particular, polyunsaturated fatty acids are known to exhibit a range of immunomodulatory properties that progress through T cell mediated events, although the molecular mechanisms of these actions have not yet been fully elucidated. Some of these immune activities are linked to polyunsaturated fatty acid-induced alteration of the composition of cellular membranes and the consequent changes in signalling pathways linked to membrane raft associated proteins. However, significant aspects of the polyunsaturated fatty acid bioactivities are mediated through their transformation to specific lipid mediators, products of cyclooxygenase, lipoxygenase or cytochrome P450 enzymatic reactions. Resulting bioactive metabolites including prostaglandins, leukotrienes and endocannabinoids are produced by and/or act upon T leukocytes through cell surface receptors and have been shown to alter T cell activation and differentiation, proliferation, cytokine production, motility and homing events. Detailed appreciation of the mode of action of these lipids presents opportunities for the design and development of therapeutic strategies aimed at regulating T cell function.

  5. SOX7 is involved in aspirin-mediated growth inhibition of human colorectal cancer cells

    Institute of Scientific and Technical Information of China (English)

    Xin Zhou; Shu-Yan Huang; Jing-Xin Feng; Yan-Yan Gao; Li Zhao; Jun Lu; Bai-Qu Huang; Yu Zhang

    2011-01-01

    AIM: To confirm the role of sex-determining region Y-box 7 (Sox7) in aspirin-mediated growth inhibition of COX-independent human colorectal cancer cells.METHODS: The cell survival percentage was examined by MTT (Moto-nuclear cell direc cytotoxicity) assay.SOX7 expression was assessed by using reverse transcription-polymerase chain reaction and Western blotting. SB203580 was used to inhibit the p38MAPK signal pathway. SOX7 promoter activity was detected by Luciferase reporter assay.RESULTS: SOX7 was upregulated by aspirin and was involved in aspirin-mediated growth inhibition of SW480 human colorectal cancer cells. The p38MAPK pathway played a role in aspirin-induced SOX7 expression, during which the AP1 transcription factors c-Jun and c-Fos upregulated SOX7 promoter activities.RESULTS: SOX7 is upregulated by aspirin and is involved in aspirin-mediated growth inhibition of human colorectal cancer SW480 cells.

  6. Activation of cell-mediated immunity by Morinda citrifolia fruit extract and its constituents.

    Science.gov (United States)

    Murata, Kazuya; Abe, Yumi; Futamura-Masudaa, Megumi; Uwaya, Akemi; Isami, Fumiyuki; Matsuda, Hideaki

    2014-04-01

    Morinda citrifolia, commonly known as noni, is a traditional natural medicine in French Polynesia and Hawaii. Functional foods derived from M. citrifolia fruit have been marketed to help prevent diseases and promote good health. The objective of this study was to assess the effects of M. citrifolia fruit on cell-mediated immunity. In the picryl chloride-induced contact dermatitis test, M. citrifolia fruit extract (Noni-ext) inhibited the suppression of cell-mediated immunity by immunosuppressive substances isolated from freeze-dried ascites of Ehrlich carcinoma-bearing mice (EC-sup). In addition, Noni-ext inhibited reduction of IL-2 production in EC-sup-treated mice and activated natural killer cells in normal mice. These results suggest that Noni-ext has multiple effects on the recovery of cell-mediated immunity. Furthermore, we investigated the active principles of Noni-ext and identified an iridoid glycoside, deacetylasperulosidic acid. Oral administration of deacetylasperulosidic acid inhibited the reduction of ear swelling, and also cancelled the suppression of IL-2 production along with the activation of natural killer cells in the same manner as that of Noni-ext.

  7. Silver Nanoparticles Induce HePG-2 Cells Apoptosis Through ROS-Mediated Signaling Pathways

    Science.gov (United States)

    Zhu, Bing; Li, Yinghua; Lin, Zhengfang; Zhao, Mingqi; Xu, Tiantian; Wang, Changbing; Deng, Ning

    2016-04-01

    Recently, silver nanoparticles (AgNPs) have been shown to provide a novel approach to overcome tumors, especially those of hepatocarcinoma. However, the anticancer mechanism of silver nanoparticles is unclear. Thus, the purpose of this study was to estimate the effect of AgNPs on proliferation and activation of ROS-mediated signaling pathway on human hepatocellular carcinoma HePG-2 cells. A simple chemical method for preparing AgNPs with superior anticancer activity has been showed in this study. AgNPs were detected by transmission electronic microscopy (TEM) and energy dispersive X-ray (EDX). The size distribution and zeta potential of silver nanoparticles were detected by Zetasizer Nano. The average size of AgNPs (2 nm) observably increased the cellular uptake by endocytosis. AgNPs markedly inhibited the proliferation of HePG-2 cells through induction of apoptosis with caspase-3 activation and PARP cleavage. AgNPs with dose-dependent manner significantly increased the apoptotic cell population (sub-G1). Furthermore, AgNP-induced apoptosis was found dependent on the overproduction of reactive oxygen species (ROS) and affecting of MAPKs and AKT signaling and DNA damage-mediated p53 phosphorylation to advance HePG-2 cells apoptosis. Therefore, our results show that the mechanism of ROS-mediated signaling pathways may provide useful information in AgNP-induced HePG-2 cell apoptosis.

  8. Silver Nanoparticles Induce HePG-2 Cells Apoptosis Through ROS-Mediated Signaling Pathways.

    Science.gov (United States)

    Zhu, Bing; Li, Yinghua; Lin, Zhengfang; Zhao, Mingqi; Xu, Tiantian; Wang, Changbing; Deng, Ning

    2016-12-01

    Recently, silver nanoparticles (AgNPs) have been shown to provide a novel approach to overcome tumors, especially those of hepatocarcinoma. However, the anticancer mechanism of silver nanoparticles is unclear. Thus, the purpose of this study was to estimate the effect of AgNPs on proliferation and activation of ROS-mediated signaling pathway on human hepatocellular carcinoma HePG-2 cells. A simple chemical method for preparing AgNPs with superior anticancer activity has been showed in this study. AgNPs were detected by transmission electronic microscopy (TEM) and energy dispersive X-ray (EDX). The size distribution and zeta potential of silver nanoparticles were detected by Zetasizer Nano. The average size of AgNPs (2 nm) observably increased the cellular uptake by endocytosis. AgNPs markedly inhibited the proliferation of HePG-2 cells through induction of apoptosis with caspase-3 activation and PARP cleavage. AgNPs with dose-dependent manner significantly increased the apoptotic cell population (sub-G1). Furthermore, AgNP-induced apoptosis was found dependent on the overproduction of reactive oxygen species (ROS) and affecting of MAPKs and AKT signaling and DNA damage-mediated p53 phosphorylation to advance HePG-2 cells apoptosis. Therefore, our results show that the mechanism of ROS-mediated signaling pathways may provide useful information in AgNP-induced HePG-2 cell apoptosis. PMID:27075340

  9. Prospects for a nonliving vaccine against Schistosomiasis based on cell-mediated immune resistance mechanisms

    Directory of Open Access Journals (Sweden)

    Stephanie L. James

    1987-01-01

    Full Text Available We have designed a vaccine model based on induction of cell-mediated immunity and shown that it protects mice against Schistosoma mansoni infection. Mice are immunized by intradermal injection with schistosome antigens plus BCG. Resistance is dependent on the route of antigen presentation and the adjuvant chosen. The pattern of resistance correlates with sensitization of T lymphocytes for production of gamma interferon, a macrophage activating lymphokine that stimulates the cellular effector mechanism of protection. Purified schistosome paramyosin, a muscle cell component present in soluble parasite antigenic preparations, is immunogenic for T lymphocytes and induces resistance when given intradermally with BCG. It is likely that this protein, and possibly other soluble molecules that are released by the parasites of a challenge infection, induce a cellular inflammatory response resulting in larval trapping and/or killing by activated macrophages. These results verify the feasibility of a vaccine against schistosomiasis based on induction of cell-mediated immune resistance mechanisms.

  10. A High Power-Density Mediator-Free Microfluidic Biophotovoltaic Device for Cyanobacterial Cells

    CERN Document Server

    Bombelli, Paolo; Herling, Therese W; Howe, Christopher J; Knowles, Tuomas P J

    2014-01-01

    Biophotovoltaics has emerged as a promising technology for generating renewable energy since it relies on living organisms as inexpensive, self-repairing and readily available catalysts to produce electricity from an abundant resource - sunlight. The efficiency of biophotovoltaic cells, however, has remained significantly lower than that achievable through synthetic materials. Here, we devise a platform to harness the large power densities afforded by miniaturised geometries. To this effect, we have developed a soft-lithography approach for the fabrication of microfluidic biophotovoltaic devices that do not require membranes or mediators. Synechocystis sp. PCC 6803 cells were injected and allowed to settle on the anode, permitting the physical proximity between cells and electrode required for mediator-free operation. We demonstrate power densities of above 100 mW/m2 for a chlorophyll concentration of 100 {\\mu}M under white light, a high value for biophotovoltaic devices without extrinsic supply of additional...

  11. Purinergic receptor antagonists inhibit odorant-mediated CREB phosphorylation in sustentacular cells of mouse olfactory epithelium

    LENUS (Irish Health Repository)

    Dooley, Ruth

    2011-08-22

    Abstract Background Extracellular nucleotides have long been known to play neuromodulatory roles and to be involved in intercellular signalling. In the olfactory system, ATP is released by olfactory neurons, and exogenous ATP can evoke an increase in intracellular calcium concentration in sustentacular cells, the nonneuronal supporting cells of the olfactory epithelium. Here we investigate the hypothesis that olfactory neurons communicate with sustentacular cells via extracellular ATP and purinergic receptor activation. Results Here we show that exposure of mice to a mixture of odorants induced a significant increase in the levels of the transcription factor CREB phosphorylated at Ser-133 in the nuclei of both olfactory sensory neurons and sustentacular cells. This activation was dependent on adenylyl cyclase III-mediated olfactory signaling and on activation of P2Y purinergic receptors on sustentacular cells. Purinergic receptor antagonists inhibited odorant-dependent CREB phosphorylation specifically in the nuclei of the sustentacular cells. Conclusion Our results point to a possible role for extracellular nucleotides in mediating intercellular communication between the neurons and sustentacular cells of the olfactory epithelium in response to odorant exposure. Maintenance of extracellular ionic gradients and metabolism of noxious chemicals by sustentacular cells may therefore be regulated in an odorant-dependent manner by olfactory sensory neurons.

  12. JNK1 protects against glucolipotoxicity-mediated beta-cell apoptosis

    DEFF Research Database (Denmark)

    Prause, Michala; Christensen, Dan Ploug; Billestrup, Nils;

    2014-01-01

    Pancreatic β-cell dysfunction is central to type 2 diabetes pathogenesis. Prolonged elevated levels of circulating free-fatty acids and hyperglycemia, also termed glucolipotoxicity, mediate β-cell dysfunction and apoptosis associated with increased c-Jun N-terminal Kinase (JNK) activity. Endoplas......Pancreatic β-cell dysfunction is central to type 2 diabetes pathogenesis. Prolonged elevated levels of circulating free-fatty acids and hyperglycemia, also termed glucolipotoxicity, mediate β-cell dysfunction and apoptosis associated with increased c-Jun N-terminal Kinase (JNK) activity....... Endoplasmic reticulum (ER) and oxidative stress are elicited by palmitate and high glucose concentrations further potentiating JNK activity. Our aim was to determine the role of the JNK subtypes JNK1, JNK2 and JNK3 in palmitate and high glucose-induced β-cell apoptosis. We established insulin-producing INS1...... INS1 cells showed increased apoptosis and cleaved caspase 9 and 3 compared to non-sense shRNA expressing control INS1 cells when exposed to palmitate and high glucose associated with increased CHOP expression, ROS formation and Puma mRNA expression. JNK2 shRNA expressing INS1 cells did not affect...

  13. 5-ALA mediated photodynamic therapy induces autophagic cell death via AMP-activated protein kinase

    Directory of Open Access Journals (Sweden)

    Lin Yu-Hsin

    2010-04-01

    Full Text Available Abstract Photodynamic therapy (PDT has been developed as an anticancer treatment, which is based on the tumor-specific accumulation of a photosensitizer that induces cell death after irradiation of light with a specific wavelength. Depending on the subcellular localization of the photosensitizer, PDT could trigger various signal transduction cascades and induce cell death such as apoptosis, autophagy, and necrosis. In this study, we report that both AMP-activated protein kinase (AMPK and mitogen-activated protein kinase (MAPK signaling cascades are activated following 5-aminolevulinic acid (ALA-mediated PDT in both PC12 and CL1-0 cells. Although the activities of caspase-9 and -3 are elevated, the caspase inhibitor zVAD-fmk did not protect cells against ALA-PDT-induced cell death. Instead, autophagic cell death was found in PC12 and CL1-0 cells treated with ALA-PDT. Most importantly, we report here for the first time that it is the activation of AMPK, but not MAPKs that plays a crucial role in mediating autophagic cell death induced by ALA-PDT. This novel observation indicates that the AMPK pathway play an important role in ALA-PDT-induced autophagy.

  14. Plasticity of adult human pancreatic duct cells by neurogenin3-mediated reprogramming.

    Directory of Open Access Journals (Sweden)

    Nathalie Swales

    Full Text Available AIMS/HYPOTHESIS: Duct cells isolated from adult human pancreas can be reprogrammed to express islet beta cell genes by adenoviral transduction of the developmental transcription factor neurogenin3 (Ngn3. In this study we aimed to fully characterize the extent of this reprogramming and intended to improve it. METHODS: The extent of the Ngn3-mediated duct-to-endocrine cell reprogramming was measured employing genome wide mRNA profiling. By modulation of the Delta-Notch signaling or addition of pancreatic endocrine transcription factors Myt1, MafA and Pdx1 we intended to improve the reprogramming. RESULTS: Ngn3 stimulates duct cells to express a focused set of genes that are characteristic for islet endocrine cells and/or neural tissues. This neuro-endocrine shift however, is incomplete with less than 10% of full duct-to-endocrine reprogramming achieved. Transduction of exogenous Ngn3 activates endogenous Ngn3 suggesting auto-activation of this gene. Furthermore, pancreatic endocrine reprogramming of human duct cells can be moderately enhanced by inhibition of Delta-Notch signaling as well as by co-expressing the transcription factor Myt1, but not MafA and Pdx1. CONCLUSIONS/INTERPRETATION: The results provide further insight into the plasticity of adult human duct cells and suggest measurable routes to enhance Ngn3-mediated in vitro reprogramming protocols for regenerative beta cell therapy in diabetes.

  15. Potential role of NKT regulatory cell ligands for the treatment of immune mediated colitis

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Natural killer T lymphocytes (NKT) have been implicated in the regulation of autoimmune processes in both mice and humans. In response to stimuli, this subset of cells rapidly produces large amounts of cytokines thereby provoking immune responses, including protection against autoimmune diseases. NKT cells are present in all lymphoid compartments, but are most abundant in the liver and bone marrow. They are activated by interaction of their T-cell receptor with glycolipids presented by CD1d, a nonpolymorphic, major histocompatibility complex class Mike molecule expressed by antigen presenting cells. Several possible ligands for NKT cells have recently been suggested, p-glucosylceramide, a naturally occurring glycolipid, is a metabolic intermediate in the anabolic and catabolic pathways of complex glycosphingolipids. Like other p-glycolipids, p-glucosylceramide has an immunomodulatory effect in several immune mediated disorders, including immune mediated colitis. Due to the broad impact that NKT cells have on the immune system, there is intense interest in understanding how NKT cells are stimulated and the extent to which NKT cell responses can be controlled. These novel ligands are currently being evaluated in animal models of colitis. Here, we discuss strategies to alter NKT lymphocyte function in various settings and the potential clinical applications of natural glycolipids.

  16. Purinergic receptor antagonists inhibit odorant-mediated CREB phosphorylation in sustentacular cells of mouse olfactory epithelium.

    LENUS (Irish Health Repository)

    Dooley, Ruth

    2012-02-01

    BACKGROUND: Extracellular nucleotides have long been known to play neuromodulatory roles and to be involved in intercellular signalling. In the olfactory system, ATP is released by olfactory neurons, and exogenous ATP can evoke an increase in intracellular calcium concentration in sustentacular cells, the nonneuronal supporting cells of the olfactory epithelium. Here we investigate the hypothesis that olfactory neurons communicate with sustentacular cells via extracellular ATP and purinergic receptor activation. RESULTS: Here we show that exposure of mice to a mixture of odorants induced a significant increase in the levels of the transcription factor CREB phosphorylated at Ser-133 in the nuclei of both olfactory sensory neurons and sustentacular cells. This activation was dependent on adenylyl cyclase III-mediated olfactory signaling and on activation of P2Y purinergic receptors on sustentacular cells. Purinergic receptor antagonists inhibited odorant-dependent CREB phosphorylation specifically in the nuclei of the sustentacular cells. CONCLUSION: Our results point to a possible role for extracellular nucleotides in mediating intercellular communication between the neurons and sustentacular cells of the olfactory epithelium in response to odorant exposure. Maintenance of extracellular ionic gradients and metabolism of noxious chemicals by sustentacular cells may therefore be regulated in an odorant-dependent manner by olfactory sensory neurons.

  17. Dehydroeffusol effectively inhibits human gastric cancer cell-mediated vasculogenic mimicry with low toxicity

    International Nuclear Information System (INIS)

    Accumulated data has shown that various vasculogenic tumor cells, including gastric cancer cells, are able to directly form tumor blood vessels via vasculogenic mimicry, supplying oxygen and nutrients to tumors, and facilitating progression and metastasis of malignant tumors. Therefore, tumor vasculogenic mimicry is a rational target for developing novel anticancer therapeutics. However, effective antitumor vasculogenic mimicry-targeting drugs are not clinically available. In this study, we purified 2,7-dihydroxyl-1-methyl-5-vinyl-phenanthrene, termed dehydroeffusol, from the traditional Chinese medicinal herb Juncus effusus L., and found that dehydroeffusol effectively inhibited gastric cancer cell-mediated vasculogenic mimicry in vitro and in vivo with very low toxicity. Dehydroeffusol significantly suppressed gastric cancer cell adhesion, migration, and invasion. Molecular mechanistic studies revealed that dehydroeffusol markedly inhibited the expression of a vasculogenic mimicry master gene VE-cadherin and reduced adherent protein exposure on the cell surface by inhibiting gene promoter activity. In addition, dehydroeffusol significantly decreased the expression of a key vasculogenic gene matrix metalloproteinase 2 (MMP2) in gastric cancer cells, and diminished MMP2 protease activity. Together, our results showed that dehydroeffusol effectively inhibited gastric cancer cell-mediated vasculogenic mimicry with very low toxicity, suggesting that dehydroeffusol is a potential drug candidate for anti-gastric cancer neovascularization and anti-gastric cancer therapy. - Highlights: • Dehydroeffusol markedly inhibits gastric cancer cell-mediated vasculogenic mimicry. • Dehydroeffusol suppresses the expression of vasculogenic mimicry key gene VE-cadherin. • Dehydroeffusol decreases the MMP2 expression and activity in gastric cancer cells. • Dehydroeffusol is a potential anti-cancer drug candidate with very low toxicity

  18. Dehydroeffusol effectively inhibits human gastric cancer cell-mediated vasculogenic mimicry with low toxicity

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Wenming; Meng, Mei; Zhang, Bin; Du, Longsheng; Pan, Yanyan; Yang, Ping; Gu, Zhenlun; Zhou, Quansheng, E-mail: quanshengzhou@yahoo.com; Cao, Zhifei, E-mail: hunancao@163.com

    2015-09-01

    Accumulated data has shown that various vasculogenic tumor cells, including gastric cancer cells, are able to directly form tumor blood vessels via vasculogenic mimicry, supplying oxygen and nutrients to tumors, and facilitating progression and metastasis of malignant tumors. Therefore, tumor vasculogenic mimicry is a rational target for developing novel anticancer therapeutics. However, effective antitumor vasculogenic mimicry-targeting drugs are not clinically available. In this study, we purified 2,7-dihydroxyl-1-methyl-5-vinyl-phenanthrene, termed dehydroeffusol, from the traditional Chinese medicinal herb Juncus effusus L., and found that dehydroeffusol effectively inhibited gastric cancer cell-mediated vasculogenic mimicry in vitro and in vivo with very low toxicity. Dehydroeffusol significantly suppressed gastric cancer cell adhesion, migration, and invasion. Molecular mechanistic studies revealed that dehydroeffusol markedly inhibited the expression of a vasculogenic mimicry master gene VE-cadherin and reduced adherent protein exposure on the cell surface by inhibiting gene promoter activity. In addition, dehydroeffusol significantly decreased the expression of a key vasculogenic gene matrix metalloproteinase 2 (MMP2) in gastric cancer cells, and diminished MMP2 protease activity. Together, our results showed that dehydroeffusol effectively inhibited gastric cancer cell-mediated vasculogenic mimicry with very low toxicity, suggesting that dehydroeffusol is a potential drug candidate for anti-gastric cancer neovascularization and anti-gastric cancer therapy. - Highlights: • Dehydroeffusol markedly inhibits gastric cancer cell-mediated vasculogenic mimicry. • Dehydroeffusol suppresses the expression of vasculogenic mimicry key gene VE-cadherin. • Dehydroeffusol decreases the MMP2 expression and activity in gastric cancer cells. • Dehydroeffusol is a potential anti-cancer drug candidate with very low toxicity.

  19. Molecular tracking of antigen-specific T cell clones in neurological immune-mediated disorders

    Science.gov (United States)

    Muraro, Paolo A.; Wandinger, Klaus-Peter; Bielekova, Bibiana; Gran, Bruno; Marques, Adriana; Utz, Ursula; McFarland, Henry F.; Jacobson, Steve; Martin, Roland

    2016-01-01

    Summary T cells recognizing self or microbial antigens may trigger or reactivate immune-mediated diseases. Monitoring the frequency of specific T cell clonotypes to assess a possible link with the course of disease has been a difficult task with currently available technology. Our goal was to track individual candidate pathogenic T cell clones, selected on the basis of previous extensive studies from patients with immune-mediated disorders of the CNS, including multiple sclerosis, HTLV-I associated myelopathy/tropical spastic paraparesis (HAM/ TSP) and chronic Lyme neuroborreliosis. We developed and applied a highly specific and sensitive technique to track single CD4+ and CD8+ T cell clones through the detection and quantification of T cell receptor (TCR) α or β chain complementarity-determining region 3 transcripts by real-time reverse transcriptase (RT)-PCR. We examined the frequency of the candidate pathogenic T cell clones in the peripheral blood and CSF during the course of neurological disease. Using this approach, we detected variations of clonal frequencies that appeared to be related to clinical course, significant enrichment in the CSF, or both. By integrating clono-type tracking with direct visualization of antigen-specific staining, we showed that a single T cell clone contributed substantially to the overall recognition of the viral peptide/MHC complex in a patient with HAM/ TSP. T cell clonotype tracking is a powerful new technology enabling further elucidation of the dynamics of expansion of autoreactive or pathogen-specific T cells that mediate pathological or protective immune responses in neurological disorders. PMID:12477694

  20. One-dimensional consolidation of over-consolidated soil under time-dependent loading

    Institute of Scientific and Technical Information of China (English)

    Kanghe XIE; Kun WANG; Guohong CHEN; Anfeng HU

    2008-01-01

    The problem of one-dimensional consolidation of over-consolidated saturated soil under time-dependent loading was studied based on semi-analytical method. The relevant computer code was developed by FORTRAN programming, and one-dimensional consolidation behavior of over-consolidated soil was investigated. It is shown that, unlike this described by traditional Terzaghi's consolidation theory, the rate of excess pore water pressure dissipation is different from that of settlement developing. The magnitude of load and that of pre-consolidation pressure as well as the loading rate has all significant influence on consolidation. With the increasing of pre-consolidation pressure and loading rate, the rate of consolidation increases correspondingly. However, an increase in load will slow down the consolidation rate.

  1. Transposon-mediated BAC transgenesis in human ES cells.

    Science.gov (United States)

    Rostovskaya, Maria; Fu, Jun; Obst, Mandy; Baer, Isabell; Weidlich, Stefanie; Wang, Hailong; Smith, Andrew J H; Anastassiadis, Konstantinos; Stewart, A Francis

    2012-10-01

    Transgenesis is a cornerstone of molecular biology. The ability to integrate a specifically engineered piece of DNA into the genome of a living system is fundamental to our efforts to understand life and exploit its implications for medicine, nanotechnology and bioprospecting. However, transgenesis has been hampered by position effects and multi-copy integration problems, which are mainly due to the use of small, plasmid-based transgenes. Large transgenes based on native genomic regions cloned into bacterial artificial chromosomes (BACs) circumvent these problems but are prone to fragmentation. Herein, we report that contrary to widely held notions, large BAC-sized constructs do not prohibit transposition. We also report the first reliable method for BAC transgenesis in human embryonic stem cells (hESCs). The PiggyBac or Sleeping Beauty transposon inverted repeats were integrated into BAC vectors by recombineering, followed by co-lipofection with the corresponding transposase in hESCs to generate robust fluorescent protein reporter lines for OCT4, NANOG, GATA4 and PAX6. BAC transposition delivers several advantages, including increased frequencies of single-copy, full-length integration, which will be useful in all transgenic systems but especially in difficult venues like hESCs. PMID:22753106

  2. 5-Azacytidine Promotes an Inhibitory T-Cell Phenotype and Impairs Immune Mediated Antileukemic Activity

    Directory of Open Access Journals (Sweden)

    Thomas Stübig

    2014-01-01

    Full Text Available Demethylating agent, 5-Azacytidine (5-Aza, has been shown to be active in treatment of myeloid malignancies. 5-Aza enhances anticancer immunity, by increasing expression of tumor-associated antigens. However, the impact of 5-Aza immune responses remains poorly understood. Here, T-cell mediated tumor immunity effects of 5-Aza, are investigated in vitro and in vivo. T-cells from healthy donors were treated with 5-Aza and analyzed by qRT-PCR and flow cytometry for changes in gene expression and phenotype. Functionality was assessed by a tumor lysis assay. Peripheral blood from patients treated with 5-Aza after alloSCT was monitored for changes in T-cell subpopulations. 5-Aza treatment resulted in a decrease in CD8+ T-cells, whereas CD4+ T-cells increased. Furthermore, numbers of IFN-γ+ T-helper 1 cells (Th1 were reduced, while Treg-cells showed substantial increase. Additionally, CD8+ T-cells exhibited limited killing capacity against leukemic target cells. In vivo data confirm the increase of Treg compartment, while CD8+ T-effector cell numbers were reduced. 5-Aza treatment results in a shift from cytotoxic to regulatory T-cells with a functional phenotype and a major reduction in proinflammatory Th1-cells, indicating a strong inhibition of tumor-specific T-cell immunity by 5-Aza.

  3. 5-Azacytidine Promotes an Inhibitory T-Cell Phenotype and Impairs Immune Mediated Antileukemic Activity

    Science.gov (United States)

    Stübig, Thomas; Luetkens, Tim; Hildebrandt, York; Atanackovic, Djordje; Binder, Thomas M. C.; Fehse, Boris; Kröger, Nicolaus

    2014-01-01

    Demethylating agent, 5-Azacytidine (5-Aza), has been shown to be active in treatment of myeloid malignancies. 5-Aza enhances anticancer immunity, by increasing expression of tumor-associated antigens. However, the impact of 5-Aza immune responses remains poorly understood. Here, T-cell mediated tumor immunity effects of 5-Aza, are investigated in vitro and in vivo. T-cells from healthy donors were treated with 5-Aza and analyzed by qRT-PCR and flow cytometry for changes in gene expression and phenotype. Functionality was assessed by a tumor lysis assay. Peripheral blood from patients treated with 5-Aza after alloSCT was monitored for changes in T-cell subpopulations. 5-Aza treatment resulted in a decrease in CD8+ T-cells, whereas CD4+ T-cells increased. Furthermore, numbers of IFN-γ+ T-helper 1 cells (Th1) were reduced, while Treg-cells showed substantial increase. Additionally, CD8+ T-cells exhibited limited killing capacity against leukemic target cells. In vivo data confirm the increase of Treg compartment, while CD8+ T-effector cell numbers were reduced. 5-Aza treatment results in a shift from cytotoxic to regulatory T-cells with a functional phenotype and a major reduction in proinflammatory Th1-cells, indicating a strong inhibition of tumor-specific T-cell immunity by 5-Aza. PMID:24757283

  4. 5-azacytidine promotes an inhibitory T-cell phenotype and impairs immune mediated antileukemic activity.

    Science.gov (United States)

    Stübig, Thomas; Badbaran, Anita; Luetkens, Tim; Hildebrandt, York; Atanackovic, Djordje; Binder, Thomas M C; Fehse, Boris; Kröger, Nicolaus

    2014-01-01

    Demethylating agent, 5-Azacytidine (5-Aza), has been shown to be active in treatment of myeloid malignancies. 5-Aza enhances anticancer immunity, by increasing expression of tumor-associated antigens. However, the impact of 5-Aza immune responses remains poorly understood. Here, T-cell mediated tumor immunity effects of 5-Aza, are investigated in vitro and in vivo. T-cells from healthy donors were treated with 5-Aza and analyzed by qRT-PCR and flow cytometry for changes in gene expression and phenotype. Functionality was assessed by a tumor lysis assay. Peripheral blood from patients treated with 5-Aza after alloSCT was monitored for changes in T-cell subpopulations. 5-Aza treatment resulted in a decrease in CD8+ T-cells, whereas CD4+ T-cells increased. Furthermore, numbers of IFN-γ + T-helper 1 cells (Th1) were reduced, while Treg-cells showed substantial increase. Additionally, CD8+ T-cells exhibited limited killing capacity against leukemic target cells. In vivo data confirm the increase of Treg compartment, while CD8+ T-effector cell numbers were reduced. 5-Aza treatment results in a shift from cytotoxic to regulatory T-cells with a functional phenotype and a major reduction in proinflammatory Th1-cells, indicating a strong inhibition of tumor-specific T-cell immunity by 5-Aza. PMID:24757283

  5. Effect of miR-451-mediated regulation of MIF expression on cell proliferation in human colon carcinoma cell line LoVo

    Institute of Scientific and Technical Information of China (English)

    孔帅

    2013-01-01

    Objective To investigate the effect of miR-451-mediated regulation of macrophage migration inhibitory factor(MIF) expression on cell proliferation in human colon carcinoma cell line LoVo.Methods A lentiviral vector

  6. Participation of CD45, NKR-P1A and ANK61 antigen in rat hepatic NK cell (pit cell)-mediated target cell cytotoxicity

    Institute of Scientific and Technical Information of China (English)

    Dian Zhong Luo; David Vermijlen; B lent Ahishali; Vasilis Triantis; Eddie Wisse; Karin Vanderkerken; Peter J.K. Kuppen

    2000-01-01

    AIM Several triggering receptors have been described to be involved in natural killer (NK) cellmediated target cytotoxicity. In these studies, NK cells derived from blood or spleen were used. Pit cells are liver-specific NK cells that possess a higher level of natural cytotoxicity and a different morphology when compared to blood NK cells. The aim of this study was to characterize the role of the NK-triggering molecules NKR-P1A, ANK61 antigen, and CD45 in pit cell-mediated killing of target cells. METHODS 51 Cr-release and DNA fragmentation were used to quantify target cell lysis and apoptosis, respectively. RESULTS Flow cytometric analysis showed that pit cells expressed CD45, NKR-P1A, and ANK61 antigen. Treatment of pit cells with monoclonal antibody ( mAb ) to CD45 ( ANK74 ) not only inhibited CC531s or YAC-1 target lysis but also apoptosis induced by pit cells. The mAbs to NKRP1A (3.2.3) and ANK61 antigen (ANK61) had no effect on pit cell-mediated CC531s or YAC-1 target cytolysis or apoptosis, while they did increase the Fcγ receptor positive (FcγR+) P815 cytolysis and apoptosis. This enhanced cytotoxicity could he inhibited by 3,4-dichloroisocoumarin, an inhibitor of granzymes. CONCLUSION These results indicate that CD45 participates in pit cell-mediated CC531s and YAC-1 target cytolysis and apoptosis. NKR-P1A and ANK61 antigen on pit cells function as activation structures against FcγR+ P815 cells, which was mediated by the perforin/granzyme pathway.

  7. Ibrutinib interferes with the cell-mediated anti-tumor activities of therapeutic CD20 antibodies: implications for combination therapy

    DEFF Research Database (Denmark)

    Da Roit, F.; Engelberts, P. J.; Taylor, R. P.;

    2015-01-01

    the possible positive or negative impact of these drugs on all known mechanisms of action of both type I and type II anti-CD20 antibodies. Pretreatment with ibrutinib for 1 hour did not increase direct cell death of cell lines or chronic lymphocytic leukemia samples mediated by anti-CD20 antibodies. Pre......-treatment with ibrutinib did not inhibit complement activation or complement-mediated lysis. In contrast, ibrutinib strongly inhibited all cell-mediated mechanisms induced by anti-CD20 antibodies rituximab, ofatumumab or obinutuzumab, either in purified systems or whole blood assays. Activation of natural killer cells...

  8. Antigenic role of stress-induced catalase of Salmonella typhimurium in cell-mediated immunity.

    OpenAIRE

    Kagaya, K; Miyakawa, Y; Watanabe, K.; Fukazawa, Y.

    1992-01-01

    The ability of the H2O2-induced catalase of Salmonella typhimurium to induce cell-mediated immunity against S. typhimurium infection in mice was examined. When exponentially growing cells of S. typhimurium were treated with 20 microM H2O2, the cells resisted killing by 1 mM H2O2 and showed the induction of a new species of catalase in addition to the constitutively produced one. Two molecules of catalases in S. typhimurium were isolated from mutant strains: H2O2-induced catalase (catalase II,...

  9. Ras protein participated in histone acetylation-mediated cell cycle control in Physarum polycephalum

    Institute of Scientific and Technical Information of China (English)

    LI Xiaoxue; LU Jun; ZHAO Yanmei; WANG Xiuli; HUANG Baiqu

    2005-01-01

    In this paper, we demonstrate that in Physarum polycephalum, a naturally synchronized slime mold, histone deacetylase (HDAC) inhibitor Trichostatin A (TSA), arrestes the cell cycle at the checkpoints of S/G2, G2/M and mitosis exit, and influences the transcription of two ras genes Ppras1 and Pprap1, as well as the Ras protein level. Antibody neutralization experiment using anti-Ras antibody treatment showed that Ras protein played an important role in cell cycle checkpoint control through regulation of the level of Cyclin B1, suggesting that Ras protein might be a key factor for histone acetylation-mediated cell cycle regulation in P. polycephalum.

  10. Evidence for a Notch1-mediated transition during olfactory ensheathing cell development.

    Science.gov (United States)

    Miller, Sophie R; Perera, Surangi N; Benito, Cristina; Stott, Simon R W; Baker, Clare V H

    2016-09-01

    Olfactory ensheathing cells (OECs) are a unique glial population found in both the peripheral and central nervous system: they ensheath bundles of unmyelinated olfactory axons from their peripheral origin in the olfactory epithelium to their central synaptic targets in the glomerular layer of the olfactory bulb. Like all other peripheral glia (Schwann cells, satellite glia, enteric glia), OECs are derived from the embryonic neural crest. However, in contrast to Schwann cells, whose development has been extensively characterised, relatively little is known about their normal development in vivo. In the Schwann cell lineage, the transition from multipotent Schwann cell precursor to immature Schwann cell is promoted by canonical Notch signalling. Here, in situ hybridisation and immunohistochemistry data from chicken, mouse and human embryos are presented that suggest a canonical Notch-mediated transition also occurs during OEC development. PMID:27271278

  11. CD13 is a novel mediator of monocytic/endothelial cell adhesion

    DEFF Research Database (Denmark)

    Mina-Osorio, Paola; Winnicka, Beata; O'Conor, Catherine;

    2008-01-01

    rearrangement and filopodia formation. Treatment with soluble recombinant (r)CD13 blocks this CD13-dependent adhesion, and CD13 molecules from monocytic and endothelial cells are present in the same immunocomplex, suggesting a direct participation of CD13 in the adhesive interaction. This concept......During inflammation, cell surface adhesion molecules guide the adhesion and migration of circulating leukocytes across the endothelial cells lining the blood vessels to access the site of injury. The transmembrane molecule CD13 is expressed on monocytes and endothelial cells and has been shown...... to mediate homotypic cell adhesion, which may imply a role for CD13 in inflammatory monocyte trafficking. Here, we show that ligation and clustering of CD13 by mAb or viral ligands potently induce myeloid cell/endothelial adhesion in a signal transduction-dependent manner involving monocytic cytoskeletal...

  12. Differential regulation of intracellular factors mediating cell cycle, DNA repair and inflammation following exposure to silver nanoparticles in human cells

    Directory of Open Access Journals (Sweden)

    AshaRani PV

    2012-02-01

    Full Text Available Abstract Background Investigating the cellular and molecular signatures in eukaryotic cells following exposure to nanoparticles will further our understanding on the mechanisms mediating nanoparticle induced effects. This study illustrates the molecular effects of silver nanoparticles (Ag-np in normal human lung cells, IMR-90 and human brain cancer cells, U251 with emphasis on gene expression, induction of inflammatory mediators and the interaction of Ag-np with cytosolic proteins. Results We report that silver nanoparticles are capable of adsorbing cytosolic proteins on their surface that may influence the function of intracellular factors. Gene and protein expression profiles of Ag-np exposed cells revealed up regulation of many DNA damage response genes such as Gadd 45 in both the cell types and ATR in cancer cells. Moreover, down regulation of genes necessary for cell cycle progression (cyclin B and cyclin E and DNA damage response/repair (XRCC1 and 3, FEN1, RAD51C, RPA1 was observed in both the cell lines. Double strand DNA damage was observed in a dose dependant manner as evidenced in γH2AX foci assay. There was a down regulation of p53 and PCNA in treated cells. Cancer cells in particular showed a concentration dependant increase in phosphorylated p53 accompanied by the cleavage of caspase 3 and PARP. Our results demonstrate the involvement of NFκB and MAP kinase pathway in response to Ag-np exposure. Up regulation of pro-inflammatory cytokines such as interleukins (IL-8, IL-6, macrophage colony stimulating factor, macrophage inflammatory protein in fibroblasts following Ag-np exposure were also observed. Conclusion In summary, Ag-np can modulate gene expression and protein functions in IMR-90 cells and U251 cells, leading to defective DNA repair, proliferation arrest and inflammatory response. The observed changes could also be due to its capability to adsorb cytosolic proteins on its surface.

  13. Human Umbilical Cord Wharton's Jelly Stem Cell Conditioned Medium Induces Tumoricidal Effects on Lymphoma Cells Through Hydrogen Peroxide Mediation.

    Science.gov (United States)

    Lin, Hao Daniel; Fong, Chui-Yee; Biswas, Arijit; Choolani, Mahesh; Bongso, Ariff

    2016-09-01

    Several groups have reported that human umbilical cord Wharton's jelly stem cells (hWJSCs) possess unique tumoricidal properties against many cancers. However, the exact mechanisms as to how hWJSCs inhibit tumor growth are not known. Recent evidence suggests that exposure of cancer cells to high hydrogen peroxide (H2 O2 ) levels from H2 O2 -releasing drugs causes their death. We therefore explored whether the tumoricidal effect of hWJSCs on lymphoma cells was mediated via H2 O2 . We first exposed lymphoma cells to six different molecular weight cut-off (MWCO) concentrates of hWJSC-conditioned medium (hWJSC-CM) (3, 5, 10, 30, 50, 100 kDa) for 48 h. Since, the 3 kDa-MWCO concentrate showed the greatest cell inhibition we then investigated whether the tumoricidal effect of the specific 3 kDa-MWCO concentrate on two different lymphoma cell lines (Ramos and Toledo) was mediated via accumulation of H2 O2 . We used a battery of assays (MTT, propidium iodide, mitochondria membrane potential, apoptosis, cell cycle, oxidative stress enzymes, hydrogen peroxide, mitochondrial superoxide, hydroxyl radical, peroxynitrile anion, and lipid peroxidation) to test this mechanism. The hWJSC-CM-3 kDa MWCO concentrate significantly decreased cell viability and mitochondrial membrane potential and increased cell death and apoptosis in both lymphoma cell lines. There were significant increases in superoxide dismutase with concomitant decreases in glutathione peroxidase, catalase, and thioredoxin peroxidase activities. H2 O2 levels, mitochondrial superoxide, hydroxyl radical, peroxynitrile anion, and lipid peroxidation were also significantly increased in both lymphoma cell lines. The results suggested that the hWJSC-CM-3 kDa MWCO concentrate regulates cellular H2 O2 leading to a tumoricidal effect and may thus be a promising anti-lymphoma agent. J. Cell. Biochem. 117: 2045-2055, 2016. © 2016 Wiley Periodicals, Inc. PMID:27392313

  14. Land evaluation by the process of agricultural land consolidation - the case of land consolidation area Berkovci

    OpenAIRE

    Knavs, Alojz

    2008-01-01

    The thesis describes the course of procedure of agricultural land consolidation in Slovenia, based on valid legislation of land consolidation of agricultural land. The main stress is given on approaches to land evaluation of agricultural land consolidation fund, which is an important step at re-distribution of land from the land consolidation fund among the land owners. The main purpose of the thesis is to point out the importance of land evaluation by the process of land consolidation and to...

  15. FINANCING MODE FOR SUSTAINABLE FARMLAND CONSOLIDATION

    Institute of Scientific and Technical Information of China (English)

    BAO Hai-jun; XU Bao-gen; WU Ci-fang; ZHOU Wang-yue

    2004-01-01

    Sustainable farmland consolidation covers ecology, economy and society, which means, its only goal is to protect eco-environment, in accordance with public benefits and economic laws. China is still a developing country, facing capital-lacking, an important but difficult problem, while sustainable farmland consolidation will need more money than common farmland consolidation. To solve the problem, this paper put forward and designed a new financing mode for farmland consolidation: BOT(Build-Operate-Transfer), which can effectively solve the financing problem and investment reclamation by the way of concession, and make sustainable farmland consolidation be realized in China.

  16. CYLD Promotes TNF-α-Induced Cell Necrosis Mediated by RIP-1 in Human Lung Cancer Cells

    Science.gov (United States)

    Lin, Xing; Chen, Qianshun; Huang, Chen

    2016-01-01

    Lung cancer is one of the most common cancers in the world. Cylindromatosis (CYLD) is a deubiquitination enzyme and contributes to the degradation of ubiquitin chains on RIP1. The aim of the present study is to investigate the levels of CYLD in lung cancer patients and explore the molecular mechanism of CYLD in the lung cancer pathogenesis. The levels of CYLD were detected in human lung cancer tissues and the paired paracarcinoma tissues by real-time PCR and western blotting analysis. The proliferation of human lung cancer cells was determined by MTT assay. Cell apoptosis and necrosis were determined by FACS assay. The results demonstrated that low levels of CYLD were detected in clinical lung carcinoma specimens. Three pairs of siRNA were used to knock down the endogenous CYLD in lung cancer cells. Knockdown of CYLD promoted cell proliferation of lung cancer cells. Otherwise overexpression of CYLD induced TNF-α-induced cell death in A549 cells and H460 cells. Moreover, CYLD-overexpressed lung cancer cells were treated with 10 μM of z-VAD-fmk for 12 hours and the result revealed that TNF-α-induced cell necrosis was significantly enhanced. Additionally, TNF-α-induced cell necrosis in CYLD-overexpressed H460 cells was mediated by receptor-interacting protein 1 (RIP-1) kinase. Our findings suggested that CYLD was a potential target for the therapy of human lung cancers.

  17. Antibody-dependent cell-mediated cytotoxicity (ADCC) toward human O+ red cells coated with anti-D antibody: comparison between lymphocyte and monocyte ADCC activity.

    OpenAIRE

    Sunada,Mitsutoshi; Suzuki, Shinya; Ota, Zensuke

    1985-01-01

    We investigated the antibody dependent cell-mediated cytotoxicity (ADCC) of lymphocytes and monocytes toward human O+ red cells coated with anti-D antibody using a 51Cr release assay. Lysis of sensitized red cells by lymphocytes occurred rapidly, but monocyte-mediated lysis occurred slowly. This difference might be due to postphagocytic 51Cr release by monocytes. ADCC of lymphocytes increased in proportion to the effector cell number, but large amounts of antibodies were required. In contrast...

  18. Diabetes and consolidation of fractures

    OpenAIRE

    T O Yalochkina; E A Pigarova

    2013-01-01

    One of the complications of diabetes in humans is inadequate bone formation resulting in osteopenia and slow consolidation of fractures. The basis of these pathological processes is a disruption of the regeneration of bone tissue in insulin deficiency and hyperglycemia, the mechanisms of which are highlighted in this mini-review. The published data indicate the need for careful monitoring of blood glucose levels and adequate replacement therapy for the prevention of skeletal complications of ...

  19. Diabetes and consolidation of fractures

    Directory of Open Access Journals (Sweden)

    T O Yalochkina

    2013-06-01

    Full Text Available One of the complications of diabetes in humans is inadequate bone formation resulting in osteopenia and slow consolidation of fractures. The basis of these pathological processes is a disruption of the regeneration of bone tissue in insulin deficiency and hyperglycemia, the mechanisms of which are highlighted in this mini-review. The published data indicate the need for careful monitoring of blood glucose levels and adequate replacement therapy for the prevention of skeletal complications of diabetes.

  20. Complement-mediated enhancement of HIV-1 infection in peripheral blood mononuclear cells

    DEFF Research Database (Denmark)

    Nielsen, S D; Sørensen, A M; Schønning, Kristian;

    1997-01-01

    3 isolates and found only a minor effect on antigen production (median enhancement 1.2-fold, range 0.6-1.5). Furthermore, addition of HIV-specific antibodies in combination with complement resulted in enhanced antigen production in 2/3 sera tested. However, the combination of complement...... and antibodies resulted in only a minor increase in enhancement of HIV infection compared to that obtained with complement alone. Finally, we found evidence of complement-mediated enhancement of HIV infection in resting PBMC. In conclusion, we demonstrated that complement-mediated enhancement of HIV infection......We investigated if complement-mediated enhancement of HIV infection occurs in peripheral blood mononuclear cells (PBMC). In 7 experiments, we evaluated the effect of human complement on HIVIIIB infection in vitro. We measured HIV antigen production on day 4 and found that pre-incubation of HIV...

  1. Matrix stiffness-mediated effects on stemness characteristics occurring in HCC cells.

    Science.gov (United States)

    You, Yang; Zheng, Qiongdan; Dong, Yinying; Xie, Xiaoying; Wang, Yaohui; Wu, Sifan; Zhang, Lan; Wang, Yingcong; Xue, Tongchun; Wang, Zhiming; Chen, Rongxin; Wang, Yanhong; Cui, Jiefeng; Ren, Zhenggang

    2016-05-31

    Matrix stiffness as an important physical attribute of extracellular matrix exerts significant impacts on biological behaviors of cancer cells such as growth, proliferation, motility, metabolism and invasion. However, its influence on cancer stemness still remains elusive. Here, we explore whether matrix stiffness-mediated effects on stemness characteristics occur in HCC cells. As the substrate stiffness increased, HCC cells exhibited high proportion of cells with CD133(+)/EpCAM(+), high expression levels of CD133, EpCAM, Nanog and SOX2, greater self-renewing ability and oxaliplatin resistance. Simultaneously, their phosphorylation levels of Akt and mTOR, as well as p-4E-BP and SOX2 expressions were also obviously upregulated. Conversely, knockdown of integrin β1 partially attenuated higher stiffness-mediated stemness characteristics in HCC cells, and reversed the phosphorylation levels of Akt and mTOR, and expressions of p-4E-BP and SOX2, suggesting that integrin β1 may deliver higher stiffness signal into HCC cells and activate mTOR signaling pathway. Additionally, mTOR inhibitor suppressed the mTOR phosphorylation level and expression levels of p-4E-BP and SOX2 in HCC cells grown on higher stiffness substrate, as well as depressed their stemness properties significantly, favoring a regulating role of mTOR signaling pathway in matrix stiffness-mediated effects on stemness. In summary, matrix stiffness may be involved in the process of stemness regulation via activating integrin β1/Akt/mTOR/SOX2 signaling pathway. To the best of our knowledge, this study first reveals a novel regulating pathway to direct the stemness characteristics in HCC cells.

  2. Pericyte actomyosin-mediated contraction at the cell-material interface can modulate the microvascular niche

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Sunyoung; Zeiger, Adam; Maloney, John M; Van Vliet, Krystyn J [Department of Materials Science and Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139 (United States); Kotecki, Maciej; Herman, Ira M, E-mail: krystyn@mit.ed, E-mail: ira.herman@tufts.ed [Department of Physiology, Tufts University School of Medicine, 145 Harrison Avenue, Boston, MA 02111 (United States)

    2010-05-19

    Pericytes physically surround the capillary endothelium, contacting and communicating with associated vascular endothelial cells via cell-cell and cell-matrix contacts. Pericyte-endothelial cell interactions thus have the potential to modulate growth and function of the microvasculature. Here we employ the experimental finding that pericytes can buckle a freestanding, underlying membrane via actin-mediated contraction. Pericytes were cultured on deformable silicone substrata, and pericyte-generated wrinkles were imaged via both optical and atomic force microscopy (AFM). The local stiffness of subcellular domains both near and far from these wrinkles was investigated by using AFM-enabled nanoindentation to quantify effective elastic moduli. Substratum buckling contraction was quantified by the normalized change in length of initially flat regions of the substrata (corresponding to wrinkle contour lengths), and a model was used to relate local strain energies to pericyte contractile forces. The nature of pericyte-generated wrinkling and contractile protein-generated force transduction was further explored by the addition of pharmacological cytoskeletal inhibitors that affected contractile forces and the effective elastic moduli of pericyte domains. Actin-mediated forces are sufficient for pericytes to exert an average buckling contraction of 38% on the elastomeric substrata employed in these in vitro studies. Actomyosin-mediated contractile forces also act in vivo on the compliant environment of the microvasculature, including the basement membrane and other cells. Pericyte-generated substratum deformation can thus serve as a direct mechanical stimulus to adjacent vascular endothelial cells, and potentially alter the effective mechanical stiffness of nonlinear elastic extracellular matrices, to modulate pericyte-endothelial cell interactions that directly influence both physiologic and pathologic angiogenesis.

  3. Common variable immunodeficiency and inclusion body myositis: a distinct myopathy mediated by natural killer cells.

    Science.gov (United States)

    Dalakas, M C; Illa, I

    1995-06-01

    Inclusion body myositis developed in two men, 36 and 48 years old with long-standing common variable immunodeficiency. Immunophenotypic analysis of the endomysial cells showed an increased number of natural killer (NK) cells (defined as CD57+, CD56+, CD3-, CD8-, CD68-) accounting for 8.5 to 9.5% of the total cells, compared with a mean of 1% in sporadic inclusion body myositis. The remaining cells were CD8+, macrophages, and CD4+ T cells. NK cells were positive for intercellular cell adhesion molecule-1 and invaded muscle fibers negative for major histocompatibility complex (MHC) class I. In contrast to ubiquitous endomysial expression of MHC class I antigen in sporadic inclusion body myositis, the MHC class I in common variable immunodeficiency and inclusion body myositis was absent or weakly expressed in only some of the muscle fibers surrounded by CD8+ cells. Enteroviral or retroviral RNA sequences were not amplified. Treatment with intravenous immunoglobulin improved strength in 1 patient whose repeated muscle biopsy specimen showed normal NK cells. We conclude that inclusion body myositis can develop in patients with common variable immunodeficiency. Common variable immunodeficiency with inclusion body myositis is an immune myopathy mediated by NK cells in a non-MHC class I-restricted cytotoxicity, and by CD8+ cells in an MHC class I-restricted process. This is the first description of an inflammatory myopathy in which NK cells participate in the myocytotoxic process.

  4. Intracellular dopamine oxidation mediates rotenone-induced apoptosis in PC12 cells

    Institute of Scientific and Technical Information of China (English)

    Hua-qing LIU; Xing-zu ZHU; En-qi WENG

    2005-01-01

    Aim: To study the role of dopamine (DA) in rotenone-induced neurotoxicity in PC12 cells. Methods: Cell viability was assessed by detecting the leakage of lactate dehydrogenase (LDH) into the medium. Apoptosis rate was measured by flow cytometry. Caspase-3-1ike activity was measured by fluorescence assay using the probe Ac-DEVD-AMC. The level of intracellular hydrogen peroxide and other peroxides in PC12 cells were quantified by loading cells with 2'-7'-Dichlorodihydrofluorescein diacetate (DCFH-DA) in fluorescence assay. Lactic acid was measured spectrophotometrically. The DA levels in PC12 cells were determined by HPLC-ECD. Results: A 48-h incubation of PC12 cells with rotenone caused an apoptotic cell death and elevated intracellular reactive oxygen species (ROS) and lactic acid accumulation. Intracellular DA depletion with reserpine significantly attenuated rotenone-induced ROS accumulation and apoptotic cell death. No change was found in rotenone-induced ROS accumulation when cells were co-treated with deprenyl. Brief treatment with reserpine at the end of rotenone treatment had no effect on rotenone-induced neurotoxicity. However,when cells were first incubated with deprenyl, a monoamine oxidase-B inhibitor for 30 min then co-incubated with rotenone plus deprenyl, a brief treatment with reserpine enhanced cell injury. Conclusion: Rotenone-induced apoptosis in PC 12 cells was mediated by intracellular dopamine oxidation.

  5. Entorhinal cortex and consolidated memory.

    Science.gov (United States)

    Takehara-Nishiuchi, Kaori

    2014-07-01

    The entorhinal cortex is thought to support rapid encoding of new associations by serving as an interface between the hippocampus and neocortical regions. Although the entorhinal-hippocampal interaction is undoubtedly essential for initial memory acquisition, the entorhinal cortex contributes to memory retrieval even after the hippocampus is no longer necessary. This suggests that during memory consolidation additional synaptic reinforcement may take place within the cortical network, which may change the connectivity of entorhinal cortex with cortical regions other than the hippocampus. Here, I outline behavioral and physiological findings which collectively suggest that memory consolidation involves the gradual strengthening of connection between the entorhinal cortex and the medial prefrontal/anterior cingulate cortex (mPFC/ACC), a region that may permanently store the learned association. This newly formed connection allows for close interaction between the entorhinal cortex and the mPFC/ACC, through which the mPFC/ACC gains access to neocortical regions that store the content of memory. Thus, the entorhinal cortex may serve as a gatekeeper of cortical memory network by selectively interacting either with the hippocampus or mPFC/ACC depending on the age of memory. This model provides a new framework for a modification of cortical memory network during systems consolidation, thereby adding a fresh dimension to future studies on its biological mechanism.

  6. Neo-lymphoid aggregates in the adult liver can initiate potent cell-mediated immunity.

    Directory of Open Access Journals (Sweden)

    Melanie Greter

    2009-05-01

    Full Text Available Subcutaneous immunization delivers antigen (Ag to local Ag-presenting cells that subsequently migrate into draining lymph nodes (LNs. There, they initiate the activation and expansion of lymphocytes specific for their cognate Ag. In mammals, the structural environment of secondary lymphoid tissues (SLTs is considered essential for the initiation of adaptive immunity. Nevertheless, cold-blooded vertebrates can initiate potent systemic immune responses even though they lack conventional SLTs. The emergence of lymph nodes provided mammals with drastically improved affinity maturation of B cells. Here, we combine the use of different strains of alymphoplastic mice and T cell migration mutants with an experimental paradigm in which the site of Ag delivery is distant from the site of priming and inflammation. We demonstrate that in mammals, SLTs serve primarily B cell priming and affinity maturation, whereas the induction of T cell-driven immune responses can occur outside of SLTs. We found that mice lacking conventional SLTs generate productive systemic CD4- as well as CD8-mediated responses, even under conditions in which draining LNs are considered compulsory for the initiation of adaptive immunity. We describe an alternative pathway for the induction of cell-mediated immunity (CMI, in which Ag-presenting cells sample Ag and migrate into the liver where they induce neo-lymphoid aggregates. These structures are insufficient to support antibody affinity maturation and class switching, but provide a novel surrogate environment for the initiation of CMI.

  7. Lipid rafts-mediated endocytosis and physiology-based cell membrane traffic models of doxorubicin liposomes.

    Science.gov (United States)

    Li, Yinghuan; Gao, Lei; Tan, Xi; Li, Feiyang; Zhao, Ming; Peng, Shiqi

    2016-08-01

    The clathrin-mediated endocytosis is likely a major mechanism of liposomes' internalization. A kinetic approach was used to assess the internalization mechanism of doxorubicin (Dox) loaded cationic liposomes and to establish physiology-based cell membrane traffic mathematic models. Lipid rafts-mediated endocytosis, including dynamin-dependent or -independent endocytosis of noncaveolar structure, was a dominant process. The mathematic models divided Dox loaded liposomes binding lipid rafts (B) into saturable binding (SB) and nonsaturable binding (NSB) followed by energy-driven endocytosis. The intracellular trafficking demonstrated early endosome-late endosome-lysosome or early/late endosome-cytoplasm-nucleus pathways. The three properties of liposome structures, i.e., cationic lipid, fusogenic lipid, and pegylation, were investigated to compare their contributions to cell membrane and intracellular traffic. The results revealed great contribution of cationic lipid DOTAP and fusogenic lipid DOPE to cell membrane binding and internalization. The valid Dox in the nuclei of HepG2 and A375 cells treated with cationic liposomes containing 40mol% of DOPE were 1.2-fold and 1.5-fold higher than that in the nuclei of HepG2 and A375 cells treated with liposomes containing 20mol% of DOPE, respectively, suggesting the dependence of cell type. This tendency was proportional to the increase of cell-associated total liposomal Dox. The mathematic models would be useful to predict intracellular trafficking of liposomal Dox.

  8. Plumbagin induces apoptosis in Her2-overexpressing breast cancer cells through the mitochondrial-mediated pathway.

    Science.gov (United States)

    Kawiak, Anna; Zawacka-Pankau, Joanna; Lojkowska, Ewa

    2012-04-27

    Breast cancer is the leading cause of death-related cancers in women. Approximately 30% of breast cancers overexpress the Her2 oncogene, which is associated with a poor prognosis and increased resistance to chemotherapy. Plumbagin (1), a constituent of species in the plant genera Drosera and Plumbago, displays antineoplastic activity toward various cancers. The present study was aimed at determining the anticancer potential of 1 toward Her2-overexpressing breast cancer cells and defining the mode of cell death induced in these cells. The results showed that 1 exhibited high antiproliferative activity toward the Her2-overexpressing cell lines SKBR3 and BT474. The antiproliferative activity of 1 was associated with apoptosis-mediated cell death, as revealed by caspase activation and an increase in the sub-G1 fraction of the cell cycle. Compound 1 increased the levels of the proapoptotic Bcl-2 family of proteins and decreased the level of the antiapoptotic Bcl-2 protein in SKBR3 and BT474 cells. Thus, these findings indicate that 1 induces apoptosis in Her2-overexpressing breast cancers through the mitochondrial-mediated pathway and suggest its potential for further investigation for the treatment of Her2-overexpressing breast cancer. PMID:22512718

  9. P-cadherin promotes collective cell migration via a Cdc42-mediated increase in mechanical forces

    Science.gov (United States)

    Plutoni, Cédric; Bazellieres, Elsa; Le Borgne-Rochet, Maïlys; Comunale, Franck; Brugues, Agusti; Séveno, Martial; Planchon, Damien; Thuault, Sylvie; Morin, Nathalie; Bodin, Stéphane; Trepat, Xavier

    2016-01-01

    Collective cell migration (CCM) is essential for organism development, wound healing, and metastatic transition, the primary cause of cancer-related death, and it involves cell–cell adhesion molecules of the cadherin family. Increased P-cadherin expression levels are correlated with tumor aggressiveness in carcinoma and aggressive sarcoma; however, how P-cadherin promotes tumor malignancy remains unknown. Here, using integrated cell biology and biophysical approaches, we determined that P-cadherin specifically induces polarization and CCM through an increase in the strength and anisotropy of mechanical forces. We show that this mechanical regulation is mediated by the P-cadherin/β-PIX/Cdc42 axis; P-cadherin specifically activates Cdc42 through β-PIX, which is specifically recruited at cell–cell contacts upon CCM. This mechanism of cell polarization and migration is absent in cells expressing E- or R-cadherin. Thus, we identify a specific role of P-cadherin through β-PIX–mediated Cdc42 activation in the regulation of cell polarity and force anisotropy that drives CCM. PMID:26783302

  10. Cytotoxicity of some oxysterols on human vascular smooth muscle cells was mediated by apoptosis.

    Science.gov (United States)

    Miyashita, Y; Shirai, K; Ito, Y; Watanabe, J; Urano, Y; Murano, T; Tomioka, H

    1997-01-01

    A decrease in smooth muscle cells is observed in advanced atherosclerotic lesion. To understand this mechanism, we selected oxysterols as candidates for toxic lipid, and examined their cytotoxicity on human cultured vascular smooth muscle cells, together with the manner of cell death. In the presence of 7-ketocholesterol or 7 beta-hydroxycholesterol (50 mumol/L), the percentage of detached cells increased significantly with dose dependency, and an increase in detached cell number and DNA nick detected by terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling study (TUNEL) preceded an increase in lactate dehydrogenase released into the medium. DNA extracted from smooth muscle cells incubated with 7-ketocholesterol or 7 beta-hydroxycholesterol showed a laddering pattern on agarose electrophoresis. In the presence of 7-ketocholesterol or 7 beta-hydroxycholesterol, fragmented DNA quantified by the quantitative sandwich enzyme immunoassay was significantly increased. From these results, it is proposed that 7-ketocholesterol and 7 beta-hydroxycholesterol are toxic to smooth muscle cells, and that this cytotoxicity is mediated by apoptosis. PMID:9638517

  11. FSAP-mediated nucleosome release from late apoptotic cells is inhibited by autoantibodies present in SLE.

    Science.gov (United States)

    Marsman, Gerben; Stephan, Femke; de Leeuw, Karina; Bulder, Ingrid; Ruinard, Jessica T; de Jong, Jan; Westra, Johanna; Bultink, Irene E M; Voskuyl, Alexandre E; Aarden, Lucien A; Luken, Brenda M; Kallenberg, Cees G M; Zeerleder, Sacha

    2016-03-01

    Inefficient clearance of apoptotic cells and the subsequent exposure of the immune system to nuclear contents are crucially involved in the pathogenesis of systemic lupus erythematosus (SLE). Factor VII-activating protease (FSAP) is activated in serum upon contact with dead cells, and releases nucleosomes from late apoptotic cells into the extracellular environment. We investigated whether FSAP-mediated nucleosome release from late apoptotic cells is affected in SLE patients. Nucleosome release in sera of 27 SLE patients and 30 healthy controls was investigated by incubating late apoptotic Jurkat cells with serum and analyzing the remaining DNA content by flow cytometry. We found that nucleosome release in sera of SLE patients with high disease activity was significantly decreased when compared with that in SLE sera obtained during low disease activity or from healthy individuals. Upon removal of IgG/IgM antibodies from SLE sera, nucleosome release was restored. Similarly, monoclonal antinuclear antibodies inhibited nucleosome release in healthy donor serum or by plasma-purified FSAP. This inhibition was lost when Fab fragments were used, suggesting that antigen cross-linking is involved. In conclusion, FSAP-mediated nucleosome release from late apoptotic cells is greatly impaired in SLE patient sera, possibly hampering the clearance of these cells and thereby propagating inflammation.

  12. Epigenetic mechanisms of cell adhesion-mediated drug resistance in multiple myeloma.

    Science.gov (United States)

    Furukawa, Yusuke; Kikuchi, Jiro

    2016-09-01

    Multiple myeloma cells acquire the resistance to anti-cancer drugs through physical and functional interactions with the bone marrow microenvironment via two overlapping mechanisms. First, bone marrow stromal cells (BMSCs) produce soluble factors, such as interleukin-6 and insulin-like growth factor-1, to activate signal transduction pathways leading to drug resistance (soluble factor-mediated drug resistance). Second, BMSCs up-regulate the expression of cell cycle inhibitors, anti-apoptotic members of the Bcl-2 family and ABC drug transporters in myeloma cells upon direct adhesion [cell adhesion-mediated drug resistance (CAM-DR)]. Elucidation of the mechanisms underlying drug resistance may greatly contribute to the advancement of cancer therapies. Recent investigations, including ours, have revealed the involvement of epigenetic alterations in drug resistance especially CAM-DR. For example, we found that class I histone deacetylases (HDACs) determine the sensitivity of proteasome inhibitors and the histone methyltransferase EZH2 regulates the transcription of anti-apoptotic genes during the acquisition of CAM-DR by myeloma cells. In addition, another histone methyltransferase MMSET was shown to confer drug resistance to myeloma cells by facilitating DNA repair. These findings provide a rationale for the inclusion of epigenetic drugs, such as HDAC inhibitors and histone methylation modifiers, in combination chemotherapy for MM patients to increase the therapeutic index. PMID:27411688

  13. Adenovirus-mediated expression of Tob1 sensitizes breast cancer cells to ionizing radiation

    Institute of Scientific and Technical Information of China (English)

    Yang JIAO; Chun-min GE; Qing-hui MENG; Jian-ping CAO; Jian TONG; Sai-jun FAN

    2007-01-01

    Aim: To investigate the effect of the Tobl gene, a member of the Transducing Molecule of ErbB2/B-cell Translocation Ggene (TOB/BTG) family, by using the adenovirus-mediated expression of Tob 1 on radiosensitivity in a human breast cancer cell line MDA-MB-231. Methods: Cell survival was determined by clonogenic assay. Apoptosis was evaluated by DNA fragmentation gel electro-phoresis and terminal deoxynucleotidyl transferase-mediated nick end labeling assay. Protein expression was analyzed by Western blot assay and DNA repair was measured by a host cell reactivation assay. Results: We demonstrated that pre-irradiation treatment with Ad5-Tob 1 significantly increased radiosensitivity,accompanying the increased induction of apoptosis and the repression of DNA damage repair. Furthermore, Ad5-Tob 1-mediated radiosensitivity correlates with the upregulation of the pro-apoptotic protein Bax and the downregulation of several DNA double strand break repair proteins, including DNA-dependent protein kinases, Ku70 and Ku80, and X-ray-sensitive complementation group 4.Conclusion: Tobl, as a new radiosensitizer, is a new target in the radiotherapy of breast cancer via increasing apoptosis and suppressing DNA repair.

  14. A repeatedly refuelable mediated biofuel cell based on a hierarchical porous carbon electrode

    Science.gov (United States)

    Fujita, Shuji; Yamanoi, Shun; Murata, Kenichi; Mita, Hiroki; Samukawa, Tsunetoshi; Nakagawa, Takaaki; Sakai, Hideki; Tokita, Yuichi

    2014-05-01

    Biofuel cells that generate electricity from renewable fuels, such as carbohydrates, must be reusable through repeated refuelling, should these devices be used in consumer electronics. We demonstrate the stable generation of electricity from a glucose-powered mediated biofuel cell through multiple refuelling cycles. This refuelability is achieved by immobilizing nicotinamide adenine dinucleotide (NAD), an electron-transfer mediator, and redox enzymes in high concentrations on porous carbon particles constituting an anode while maintaining their electrochemical and enzymatic activities after the immobilization. This bioanode can be refuelled continuously for more than 60 cycles at 1.5 mA cm-2 without significant potential drop. Cells assembled with these bioanodes and bilirubin-oxidase-based biocathodes can be repeatedly used to power a portable music player at 1 mW cm-3 through 10 refuelling cycles. This study suggests that the refuelability within consumer electronics should facilitate the development of long and repeated use of the mediated biofuel cells as well as of NAD-based biosensors, bioreactors, and clinical applications.

  15. EVALUASI PENGGUNAAN METILEN BIRU SEBAGAI MEDIATOR ELEKTRON PADA MICROBIAL FUEL CELL DENGAN BIOKATALIS ACETOBACTER ACETI

    Directory of Open Access Journals (Sweden)

    Dani Permana

    2013-05-01

    Full Text Available Microbial fuel cell (MFC merupakan salah satu teknologi sel bahan bakar alternatif yang dapat diperbarui. MFC memanfaatkan proses oksidasi senyawa kimia oleh biokatalis untuk menghasilkan energi listrik daya rendah. Tujuan dari penelitian ini adalah mengetahui kinerja MFC dengan dan tanpa mediator elektron metilen biru (MB menggunakan biokatalis Acetobacter aceti dan substrat glukosa agar diperoleh energi listrik. Metode yang dilakukan adalah peremajaan kultur A. aceti, persiapan inokulum, persiapan reaktor MFC, persiapan media MFC dengan substrat glukosa 2% dengan dan tanpa mediator MB, pencuplikan secara periodik, penentuan kurva pertumbuhan, arus, potensial, kerapatan daya, energi, kadar glukosa dan tingkat keasaman (pH. Hasil penelitian menunjukkan bahwa MFC dengan mediator menghasilkan kuat arus sebesar 0,040 mA, potensial 878 mV, kerapatan daya 0,395 mW/cm2, energi maksimum 3,685 kJ, pemanfaatan glukosa 93,02% dan pH akhir 3,33, sedangkan MFC tanpa mediator menghasilkan kuat arus 0,035 mA, potensial 773 mV, kerapatan daya 0,290 mW/cm2, energi maksimum 2,434 kJ, pemanfaatan glukosa 90,16% dan pH akhir 3,24. Perolehan kerapatan daya pada kedua jenis MFC masih tergolong kecil dan tidak berbeda secara signifikan. Berdasarkan hasil penelitian dapat disimpulkan bahwa penggunaan mediator MB hanya berpengaruh terhadap perolehan potensial pada MFC dengan kondisi perlakuan yang diterapkan dalam penelitian ini.

  16. Stage-specific expression of TNFα regulates bad/bid-mediated apoptosis and RIP1/ROS-mediated secondary necrosis in Birnavirus-infected fish cells.

    Directory of Open Access Journals (Sweden)

    Wei-Lun Wang

    Full Text Available Infectious pancreatic necrosis virus (IPNV can induce Bad-mediated apoptosis followed by secondary necrosis in fish cells, but it is not known how these two types of cell death are regulated by IPNV. We found that IPNV infection can regulate Bad/Bid-mediated apoptotic and Rip1/ROS-mediated necrotic death pathways via the up-regulation of TNFα in zebrafish ZF4 cells. Using a DNA microarray and quantitative RT-PCR analyses, two major subsets of differentially expressed genes were characterized, including the innate immune response gene TNFα and the pro-apoptotic genes Bad and Bid. In the early replication stage (0-6 h post-infection, or p.i., we observed that the pro-inflammatory cytokine TNFα underwent a rapid six-fold induction. Then, during the early-middle replication stages (6-12 h p.i., TNFα level was eight-fold induction and the pro-apoptotic Bcl-2 family members Bad and Bid were up-regulated. Furthermore, specific inhibitors of TNFα expression (AG-126 or TNFα-specific siRNA were used to block apoptotic and necrotic death signaling during the early or early-middle stages of IPNV infection. Inhibition of TNFα expression dramatically reduced the Bad/Bid-mediated apoptotic and Rip1/ROS-mediated necrotic cell death pathways and rescued host cell viability. Moreover, we used Rip1-specific inhibitors (Nec-1 and Rip1-specific siRNA to block Rip1 expression. The Rip1/ROS-mediated secondary necrotic pathway appeared to be reduced in IPNV-infected fish cells during the middle-late stage of infection (12-18 h p.i.. Taken together, our results indicate that IPNV triggers two death pathways via up-stream induction of the pro-inflammatory cytokine TNFα, and these results may provide new insights into the pathogenesis of RNA viruses.

  17. siRNA-mediated downregulation of TC21 sensitizes esophageal cancer cells to cisplatin

    Institute of Scientific and Technical Information of China (English)

    Md.Raghibul Hasan; Shyam Singh Chauhan; Rinu Sharma; Ranju Ralhan

    2012-01-01

    AIM:To determine the functional significance of TC21 in esophageal squamous cell carcinoma (ESCC).METHODS:TC21 siRNA transfection was carried out using Hyperfectamine to knock down TC21,and transcripts were analyzed by reverse transcription-polymerase chain reaction and protein by Western blotting.We demonstrated the effect of TC21 downregulation of cell signaling in esophageal cancer cells by assessing the phosphorylation status of its downstream targets,phosphoinositide 3-kinase (PI3K),phosphatase and tensin homolog (PTEN),protein kinase B (pAkt),nuclear factor-κB (NF-κB) and cyclinD1 using specific antibodies.Cell survival analysis after cisplatin treatment was carried out by cell viability assay and cell cycle analysis using flow cytometry.RESULTS:TC21 knockdown in human ESCC cell line TE13 cells,showed only a marginal increase (14.2%) in cell death compared with control cells.The expressions of the signaling proteins PI3K and pAkt,transcription factor NF-κB,and cell cycle protein cyclin D1 were markedly decreased in response to TC21 downregulation,whereas the level of pPTEN,an antagonist of PI3K,was increased.In addition,we evaluated the potential of TC21 as a putative target for sensitizing ESCC cells to the chemotherapeutic agent dsplatin.Increased cell death (38.4%) was observed in cells treated with cisplatin after TC21 knockdown compared with cells which were treated with cisplatin alone (20% cell death).CONCLUSION:Results suggest that TC21 mediates its effects via the PI3K-Akt pathway,NF-κB and cydin D1,and enhances chemoresistance in esophageal cancer cells.

  18. Antibody induced CD4 down-modulation of T cells is site-specifically mediated by CD64(+) cells.

    Science.gov (United States)

    Vogel, Stephanie; Grabski, Elena; Buschjäger, Daniela; Klawonn, Frank; Döring, Marius; Wang, Junxi; Fletcher, Erika; Bechmann, Ingo; Witte, Torsten; Durisin, Martin; Schraven, Burkhart; Mangsbo, Sara M; Schönfeld, Kurt; Czeloth, Niklas; Kalinke, Ulrich

    2015-12-16

    Treatment of PBMC with the CD4-specific mAb BT-061 induces CD4 down-modulation of T cells. Here we report that addition of BT-061 to purified T cells did not confer this effect, whereas incubation of T cells in BT-061 coated wells restored CD4 down-modulation. These results implied that Fcγ receptor mediated cell-cell interactions played a role. In consistence with this hypothesis PBMC depleted of CD64(+) monocytes did not confer CD4 down-modulation of BT-061 decorated T cells. Strikingly, CD4 down-modulation was observed in BT-061 treated synovial fluid punctuated from patients' inflamed joints that comprised enhanced numbers of CD64(+) cells. In contrast, in a circulating whole blood system injection of BT-061 did not induce CD4 down-modulation, due to CD64 saturation by serum IgG. Similarly, tonsil derived mononuclear cells devoid of CD64(+) cells did not show CD4 down-modulation, whereas addition of blood derived monocytes restored the effect. Thus, the interaction of BT-061 decorated T cells with CD64(+) cells is needed for CD4 down-modulation, implying that in patients BT-061 would primarily induce CD4 down-modulation at inflammatory sites. These results highlight the need not only to examine the interaction of a given mAb with single FcγR, but also the immunological environment that is appropriate to support such interactions.

  19. PD-L1 Expression on Retrovirus-Infected Cells Mediates Immune Escape from CD8+ T Cell Killing

    Science.gov (United States)

    Neff, C. Preston; Gibbert, Kathrin; Dietze, Kirsten K.; Werner, Tanja; Liu, Jia; Chen, Lieping; Lang, Karl S.; Palmer, Brent E.; Dittmer, Ulf; Zelinskyy, Gennadiy

    2015-01-01

    Cytotoxic CD8+ T Lymphocytes (CTL) efficiently control acute virus infections but can become exhausted when a chronic infection develops. Signaling of the inhibitory receptor PD-1 is an important mechanism for the development of virus-specific CD8+ T cell dysfunction. However, it has recently been shown that during the initial phase of infection virus-specific CD8+ T cells express high levels of PD-1, but are fully competent in producing cytokines and killing virus-infected target cells. To better understand the role of the PD-1 signaling pathway in CD8+ T cell cytotoxicity during acute viral infections we analyzed the expression of the ligand on retrovirus-infected cells targeted by CTLs. We observed increased levels of PD-L1 expression after infection of cells with the murine Friend retrovirus (FV) or with HIV. In FV infected mice, virus-specific CTLs efficiently eliminated infected target cells that expressed low levels of PD-L1 or that were deficient for PD-L1 but the population of PD-L1high cells escaped elimination and formed a reservoir for chronic FV replication. Infected cells with high PD-L1 expression mediated a negative feedback on CD8+ T cells and inhibited their expansion and cytotoxic functions. These findings provide evidence for a novel immune escape mechanism during acute retroviral infection based on PD-L1 expression levels on virus infected target cells. PMID:26484769

  20. PD-L1 Expression on Retrovirus-Infected Cells Mediates Immune Escape from CD8+ T Cell Killing.

    Directory of Open Access Journals (Sweden)

    Ilseyar Akhmetzyanova

    2015-10-01

    Full Text Available Cytotoxic CD8+ T Lymphocytes (CTL efficiently control acute virus infections but can become exhausted when a chronic infection develops. Signaling of the inhibitory receptor PD-1 is an important mechanism for the development of virus-specific CD8+ T cell dysfunction. However, it has recently been shown that during the initial phase of infection virus-specific CD8+ T cells express high levels of PD-1, but are fully competent in producing cytokines and killing virus-infected target cells. To better understand the role of the PD-1 signaling pathway in CD8+ T cell cytotoxicity during acute viral infections we analyzed the expression of the ligand on retrovirus-infected cells targeted by CTLs. We observed increased levels of PD-L1 expression after infection of cells with the murine Friend retrovirus (FV or with HIV. In FV infected mice, virus-specific CTLs efficiently eliminated infected target cells that expressed low levels of PD-L1 or that were deficient for PD-L1 but the population of PD-L1high cells escaped elimination and formed a reservoir for chronic FV replication. Infected cells with high PD-L1 expression mediated a negative feedback on CD8+ T cells and inhibited their expansion and cytotoxic functions. These findings provide evidence for a novel immune escape mechanism during acute retroviral infection based on PD-L1 expression levels on virus infected target cells.

  1. Preliminary design report for the prototypical fuel rod consolidation system

    International Nuclear Information System (INIS)

    This report documents NUTECH's preliminary design of a dry, spent fuel rod consolidation system. This preliminary design is the result of Phase I of a planned four phase project. The present report on this project provides a considerable amount of detail for a preliminary design effort. The design and all of its details are described in this Preliminary Design Report (PDR). The NUTECH dry rod consolidation system described herein is remotely operated. It provides for automatic operation, but with operator hold points between key steps in the process. The operator has the ability to switch to a manual operation mode at any point in the process. The system is directed by the operator using an executive computer which controls and coordinates the operation of the in-cell equipment. The operator monitors the process using an in-cell closed circuit television (CCTV) system with audio output and equipment status displays on the computer monitor. The in-cell mechanical equipment consists of the following: (1) two overhead cranes with manipulators; (2) a multi-degree of freedom fuel handling table and its clamping equipment; (3) a fuel assembly end fitting removal station and its tools; (4) a consolidator (which pulls rods, assembles the consolidated bundle and loads the canister); (5) a canister end cap welder and weld inspection system; (6) decontamination systems; and (7) the CCTV and microphone systems

  2. Virus-Specific Antibody, in the Absence of T Cells, Mediates Demyelination in Mice Infected with a Neurotropic Coronavirus

    OpenAIRE

    Kim, Taeg S.; Perlman, Stanley

    2005-01-01

    Mice infected with mouse hepatitis virus strain JHM develop an inflammatory demyelinating disease in the central nervous system with many similarities to human multiple sclerosis. The mouse disease is primarily immune-mediated because demyelination is not detected in JHM-infected mice lacking T or B cells but does occur after transfer of JHM-specific T cells. Although less is known about the ability of antibodies to mediate demyelination, the presence of oligoclonally expanded B cells and hig...

  3. Intracellular protease activation in apoptosis and cell-mediated cytotoxicity characterized by cell-permeable fluorogenic protease substrates

    Institute of Scientific and Technical Information of China (English)

    Beverly Z Packard; Akira Komoriya

    2008-01-01

    Over the past decade the importance of signaling from reporter molecules inside live cells and tissues has been clearly established. Biochemical events related to inflammation, tumor metastasis and proliferation, and viral infectivity and replication are examples of processes being further defined as more molecular tools for live cell measurements become available. Moreover, in addition to quantitating parameters related to physiologic processes, real-time imaging of molecular interactions that compose basic cellular activities are providing insights into understanding disease mechanisms as well as extending clinical efficacy of therapeutic regimens. In this review the use of highly cell-permeable fluorogenic substrates that report protease activities inside live cells is described; applications to defining the molecular events of two cellular processes, i.e., apoptosis and cell-mediated cytotoxicity, are then illustrated.

  4. Tc17 CD8+ T cells potentiate Th1-mediated autoimmune diabetes in a mouse model.

    Science.gov (United States)

    Saxena, Amit; Desbois, Sabine; Carrié, Nadège; Lawand, Myriam; Mars, Lennart T; Liblau, Roland S

    2012-09-15

    An increase in IL-17-producing CD8+ T (Tc17) cells has been reported in the peripheral blood of children with recent onset type 1 diabetes (T1D), but their contribution to disease pathogenesis is still unknown. To directly study the pathogenic potential of β cell-specific Tc17 cells, we used an experimental model of T1D based on the expression of the neo-self Ag hemagglutinin (HA) in the β cells of the pancreas. When transferred alone, the IL-17-producing HA-specific CD8+ T cells homed to the pancreatic lymph nodes without causing any pancreatic infiltration or tissue destruction. When transferred together with small numbers of diabetogenic HA-specific CD4+ T cells, a strikingly different phenotype developed. Under these conditions, Tc17 cells sustained disease progression, driving the destruction of β-islet cells, causing hyperglycemia and ultimately death. Disease progression did not correlate with functional or numerical alterations among the HA-specific CD4+ T cells. Rather, the transferred CD8+ T cells accumulated in the pancreatic islets and a considerable fraction converted, under the control of IL-12, to an IFN-γ-producing phenotype. Our data indicate that Tc17 cells are not diabetogenic but can potentiate a Th1-mediated disease. Plasticity of the Tc17 lineage is associated with transition to overt disease in this experimental model of T1D. PMID:22904307

  5. Pycnogenol (PYC) induces apoptosis in human fibrosarcoma (HFS) cells under metal-mediated oxidative stress.

    Science.gov (United States)

    Park, Yeon Sun; Kim, Young Gon

    2011-01-01

    Pycnogenol (PYC), polyphenolic compounds with antioxidant activity, acted as a prooxidant. PYC caused oxidative stress in human fibrosarcoma cells (HFS) when administered following pretreatment with iron chloride. The generated reactive oxygen species (ROS) caused the formation of 8-hydroxy-2'-deoxyguanosine (8-OHdG) in DNA and resulted in more apoptosis in HFS cells than in the human fibroblastoma (HFB) cells. DNA damage and cellular viability at different PYC concentrations were closely consistent with cell growth, high performance liquid chromatography (HPLC), Enzyme Linked Immunosorbent Assay (ELISA) and assays of two major antioxidant enzymes, superoxide dismutase (SOD) and catalase. Although the presence of PYC induced total SOD and catalase activities under oxidative stress in dose dependent fashion, more apoptotic cells were induced in HFS cells with increased [8-OHdG] than in HFB cells. The results suggest that PYC selectively induced cell death in HFS cells. This further confirmed that PYC-induced apoptosis is mediated primarily through the activation of caspase-3 apoptotic marker in HFS cells but not in HFB cells. We conclude that PYC would behave as either antioxidant or prooxidant dependant upon the cellular types. PMID:22754951

  6. DNA Damage: A Sensible Mediator of the Differentiation Decision in Hematopoietic Stem Cells and in Leukemia

    Directory of Open Access Journals (Sweden)

    Cary N. Weiss

    2015-03-01

    Full Text Available In the adult, the source of functionally diverse, mature blood cells are hematopoietic stem cells, a rare population of quiescent cells that reside in the bone marrow niche. Like stem cells in other tissues, hematopoietic stem cells are defined by their ability to self-renew, in order to maintain the stem cell population for the lifetime of the organism, and to differentiate, in order to give rise to the multiple lineages of the hematopoietic system. In recent years, increasing evidence has suggested a role for the accumulation of reactive oxygen species and DNA damage in the decision for hematopoietic stem cells to exit quiescence and to differentiate. In this review, we will examine recent work supporting the idea that detection of cell stressors, such as oxidative and genetic damage, is an important mediator of cell fate decisions in hematopoietic stem cells. We will explore the benefits of such a system in avoiding the development and progression of malignancies, and in avoiding tissue exhaustion and failure. Additionally, we will discuss new work that examines the accumulation of DNA damage and replication stress in aging hematopoietic stem cells and causes us to rethink ideas of genoprotection in the bone marrow niche.

  7. Immortalization of pig fibroblast cells by transposon-mediated ectopic expression of porcine telomerase reverse transcriptase.

    Science.gov (United States)

    He, Shan; Li, Yangyang; Chen, Yang; Zhu, Yue; Zhang, Xinyu; Xia, Xiaoli; Sun, Huaichang

    2016-08-01

    Pigs are the most economically important livestock, but pig cell lines useful for physiological studies and/or vaccine development are limited. Although several pig cell lines have been generated by oncogene transformation or human telomerase reverse transcriptase (TERT) immortalization, these cell lines contain viral sequences and/or antibiotic resistance genes. In this study, we established a new method for generating pig cell lines using the Sleeping Beauty (SB) transposon-mediated ectopic expression of porcine telomerase reverse transcriptase (pTERT). The performance of the new method was confirmed by generating a pig fibroblast cell (PFC) line. After transfection of primary PFCs with the SB transposon system, one cell clone containing the pTERT expression cassette was selected by dilution cloning and passed for different generations. After passage for more than 40 generations, the cell line retained stable expression of ectopic pTERT and continuous growth potential. Further characterization showed that the cell line kept the fibroblast morphology, growth curve, population doubling time, cloning efficiency, marker gene expression pattern, cell cycle distribution and anchorage-dependent growth property of the primary cells. These data suggest that the new method established is useful for generating pig cell lines without viral sequence and antibiotic resistant gene. PMID:26341227

  8. Mediation of calcium oxalate crystal growth on human kidney epithelial cells with different degrees of injury

    International Nuclear Information System (INIS)

    The current study examined the role of injured human kidney tubular epithelial cell (HKC) in the mediation of formation of calcium oxalate (CaOxa) crystals by means of scanning electronic microscopy and X-ray diffraction. HKC was injured using different concentrations of H2O2. Cell injury resulted in a significant decrease in cell viability and superoxide dismutase (SOD) concentration and an increase in the level of malondialdehyde (MDA) and expression of osteopontin (OPN). Injured cells not only promote nucleation and aggregation of CaOxa crystals, but also induce the formation of calcium oxalate monohydrate (COM) crystals that strongly adhere to cells. These results imply that injured HKCs promote stone formation by providing more nucleating sites for crystals, promoting the aggregation of crystals, and inducing the formation of COM crystals. - Graphical abstract: Injured cells promote nucleation and aggregation of CaOxa crystals, induce the formation of calcium oxalate monohydrate (COM) crystals. Highlights: ► A direct nucleation and growth of CaOxa crystals on both normal and injured cells. ► Stronger green fluorescence, i.e. OPN expression, was seen on the injury cell surface ► Injured cells promote nucleation and aggregation of CaOxa crystals. ► Injured cells induce the formation of calcium oxalate monohydrate crystals. ► H2O2 decrease cell viability in a dose-dependent manner at 0.1–1 mmol/L.

  9. Human serum activates CIDEB-mediated lipid droplet enlargement in hepatoma cells

    International Nuclear Information System (INIS)

    Highlights: •Human serum induced differentiation of hepatoma cells increases cellular lipid droplet (LD) size. •The observed increase in LD size correlates with increased PGC-1α and CIDEB expression. •Induction of CIDEB expression correlates with rescue of VLDL secretion and loss of ADRP. •siRNA knockdown of CIDEB impairs the human serum mediated increase in LD size. •This system represents a cost-efficient model to study CIDEB’s role in lipid biology. -- Abstract: Human hepatocytes constitutively express the lipid droplet (LD) associated protein cell death-inducing DFFA-like effector B (CIDEB). CIDEB mediates LD fusion, as well as very-low-density lipoprotein (VLDL) maturation. However, there are limited cell culture models readily available to study CIDEB’s role in these biological processes, as hepatoma cell lines express negligible levels of CIDEB. Recent work has highlighted the ability of human serum to differentiate hepatoma cells. Herein, we demonstrate that culturing Huh7.5 cells in media supplemented with human serum activates CIDEB expression. This activation occurs through the induced expression of PGC-1α, a positive transcriptional regulator of CIDEB. Coherent anti-Stokes Raman scattering (CARS) microscopy revealed a correlation between CIDEB levels and LD size in human serum treated Huh7.5 cells. Human serum treatment also resulted in a rapid decrease in the levels of adipose differentiation-related protein (ADRP). Furthermore, individual overexpression of CIDEB was sufficient to down-regulate ADRP protein levels. siRNA knockdown of CIDEB revealed that the human serum mediated increase in LD size was CIDEB-dependent. Overall, our work highlights CIDEB’s role in LD fusion, and presents a new model system to study the PGC-1α/CIDEB pathway’s role in LD dynamics and the VLDL pathway

  10. Susceptibility to T cell-mediated liver injury is enhanced in asialoglycoprotein receptor-deficient mice.

    Science.gov (United States)

    McVicker, Benita L; Thiele, Geoffrey M; Casey, Carol A; Osna, Natalia A; Tuma, Dean J

    2013-05-01

    T cell activation and associated pro-inflammatory cytokine production is a pathological feature of inflammatory liver disease. It is also known that liver injury is associated with marked impairments in the function of many hepatic proteins including a hepatocyte-specific binding protein, the asialoglycoprotein receptor (ASGPR). Recently, it has been suggested that hepatic ASGPRs may play an important role in the physiological regulation of T lymphocytes, leading to our hypothesis that ASGPR defects correlate with inflammatory-mediated events in liver diseases. Therefore, in this study we investigated whether changes in hepatocellular ASGPR expression were related to the dysregulation of intrahepatic T lymphocytes and correlate with the development of T-cell mediated hepatitis. Mice lacking functional ASGPRs (receptor-deficient, RD), and wild-type (WT) controls were intravenously injected with T-cell mitogens, Concanavalin A (Con A) or anti-CD3 antibody. As a result of T cell mitogen treatment, RD mice lacking hepatic ASGPRs displayed enhancements in liver pathology, transaminase activities, proinflammatory cytokine expression, and caspase activation compared to that observed in normal WT mice. Furthermore, FACS analysis demonstrated that T-cell mitogen administration resulted in a significant rise in the percentage of CD8+ lymphocytes present in the livers of RD animals versus WT mice. Since these two mouse strains differ only in whether they express the hepatic ASGPR, it can be concluded that proper ASGPR function exerts a protective effect against T cell mediated hepatitis and that impairments to this hepatic receptor could be related to the accumulation of cytotoxic T cells that are observed in inflammatory liver diseases.

  11. Efficient nanoparticle mediated sustained RNA interference in human primary endothelial cells

    Energy Technology Data Exchange (ETDEWEB)

    Mukerjee, Anindita; Shankardas, Jwalitha; Ranjan, Amalendu P; Vishwanatha, Jamboor K, E-mail: Jamboor.vishwanatha@unthsc.edu [Department of Molecular Biology and Immunology and Institute for Cancer Research, Graduate School of Biomedical Sciences, University of North Texas Health Science Center, Fort Worth, TX 76107 (United States)

    2011-11-04

    Endothelium forms an important target for drug and/or gene therapy since endothelial cells play critical roles in angiogenesis and vascular functions and are associated with various pathophysiological conditions. RNA mediated gene silencing presents a new therapeutic approach to overcome many such diseases, but the major challenge of such an approach is to ensure minimal toxicity and effective transfection efficiency of short hairpin RNA (shRNA) to primary endothelial cells. In the present study, we formulated shAnnexin A2 loaded poly(D,L-lactide-co-glycolide) (PLGA) nanoparticles which produced intracellular small interfering RNA (siRNA) against Annexin A2 and brought about the downregulation of Annexin A2. The per cent encapsulation of the plasmid within the nanoparticle was found to be 57.65%. We compared our nanoparticle based transfections with Lipofectamine mediated transfection, and our studies show that nanoparticle based transfection efficiency is very high ({approx}97%) and is more sustained compared to conventional Lipofectamine mediated transfections in primary retinal microvascular endothelial cells and human cancer cell lines. Our findings also show that the shAnnexin A2 loaded PLGA nanoparticles had minimal toxicity with almost 95% of cells being viable 24 h post-transfection while Lipofectamine based transfections resulted in only 30% viable cells. Therefore, PLGA nanoparticle based transfection may be used for efficient siRNA transfection to human primary endothelial and cancer cells. This may serve as a potential adjuvant treatment option for diseases such as diabetic retinopathy, retinopathy of prematurity and age related macular degeneration besides various cancers.

  12. The role of estrogen receptor alpha in mediating chemoresistance in breast cancer cells

    Directory of Open Access Journals (Sweden)

    Jiang Zhinong

    2012-05-01

    Full Text Available Abstract Introduction Previous studies suggested that estrogen receptor alpha (ERα plays an important role in the chemoresistance of breast cancers. However, large random trials failed to demonstrate any benefit of the concurrent estrogen antagonist tamoxifen on the chemotherapy efficacy. Thus, in the present study, the importance of the role of ERα in the chemoresistance of breast cancer cells was investigated. Methods The ERα-transfected Bcap37 cells and natural ERα-positive T47D breast cancer cells were treated using chemotherapeutic agents with or without 17-beta estradiol (E2 pretreatment. Their viabilities were assessed using 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide assays. The dead cell rates were determined using propidium iodide dye exclusion tests, and the expression levels of Bcl-2 and Bax were detected through Western blot analysis. The effects of E2 on the growth of breast cancer cells were also determined via cell growth curve and cell cycle analysis. Results ERα activation by E2 increased the sensitivity of natural ERα-positive T47D breast cancer cells to chemotherapeutic agents. However, the increase in ERα expression in ERα-negative Bcap37 breast cancer cells also significantly increased their resistance. These phenomena cannot be explained by asserting that ERα mediated the chemoresistance of breast cancer cells by regulating the expression of Bcl-2 and Bax. Our findings show that ERα activation upregulated the expression of Bcl-2 in natural ERα-positive T47D breast cancer cells, whereas ERα activation by E2 downregulated and upregulated the Bcl-2 and Bax expression levels, respectively, in ERα-transfected Bcap37 cells. This phenomenon was due to the influence of ERα on the growth of breast cancer cells. Specifically, ERα activation enhanced the growth of natural ERα-positive breast cancer cells and thus increased their sensitivity to chemotherapeutic agents. However, ERα activation also

  13. Painting factor H onto mesenchymal stem cells protects the cells from complement- and neutrophil-mediated damage.

    Science.gov (United States)

    Li, Yan; Qiu, Wen; Zhang, Lingjun; Fung, John; Lin, Feng

    2016-09-01

    Mesenchymal stem cells (MSCs) are undergoing intensive testing in clinical trials as a promising new therapy for many inflammatory diseases and for regenerative medicine, but further optimization of current MSC-based therapies is required. In this study, we found that in addition to direct complement-mediated attack through the assembly of membrane attack complexes (MACs) that we and others have recently reported, of the released complement activation products, C5a, but not C3a, activates neutrophils in the blood to further damage MSCs through oxidative burst. In addition, we have developed a simple method for painting factor H, a native complement inhibitor, onto MSCs to locally inhibit complement activation on MSCs. MSCs painted with factor H are protected from both MAC- and neutrophil-mediated attack and are significantly more effective in inhibiting antigen-specific T cell responses than the mock-painted MSCs both in vitro and in vivo. PMID:27343468

  14. Stress-stiffening-mediated stem-cell commitment switch in soft responsive hydrogels

    Science.gov (United States)

    Das, Rajat K.; Gocheva, Veronika; Hammink, Roel; Zouani, Omar F.; Rowan, Alan E.

    2016-03-01

    Bulk matrix stiffness has emerged as a key mechanical cue in stem cell differentiation. Here, we show that the commitment and differentiation of human mesenchymal stem cells encapsulated in physiologically soft (~0.2-0.4 kPa), fully synthetic polyisocyanopeptide-based three-dimensional (3D) matrices that mimic the stiffness of adult stem cell niches and show biopolymer-like stress stiffening, can be readily switched from adipogenesis to osteogenesis by changing only the onset of stress stiffening. This mechanical behaviour can be tuned by simply altering the material’s polymer length whilst maintaining stiffness and ligand density. Our findings introduce stress stiffening as an important parameter that governs stem cell fate in a 3D microenvironment, and reveal a correlation between the onset of stiffening and the expression of the microtubule-associated protein DCAMKL1, thus implicating DCAMKL1 in a stress-stiffening-mediated, mechanotransduction pathway that involves microtubule dynamics in stem cell osteogenesis.

  15. Cathepsin L knockdown enhances curcumin-mediated inhibition of growth, migration, and invasion of glioma cells.

    Science.gov (United States)

    Fei, Yao; Xiong, Yajie; Zhao, Yifan; Wang, Wenjuan; Han, Meilin; Wang, Long; Tan, Caihong; Liang, Zhongqin

    2016-09-01

    Curcumin can be used to prevent and treat cancer. However, its exact underlying molecular mechanisms remain poorly understood. Cathepsin L, a lysosomal cysteine protease, is overexpressed in several cancer types. This study aimed to determine the role of cathepsin L in curcumin-mediated inhibition of growth, migration, and invasion of glioma cells. Results revealed that the activity of cathepsin L was enhanced in curcumin-treated glioma cells. Cathepsin L knockdown induced by RNA interference significantly promoted curcumin-induced cytotoxicity, apoptosis, and cell cycle arrest. The knockdown also inhibited the migration and invasion of glioma cells. Our results suggested that the inhibition of cathepsin L can enhance the sensitivity of glioma cells to curcumin. Therefore, cathepsin L may be a new target to enhance the efficacy of curcumin against cancers. PMID:27373979

  16. Fasting-Mimicking Diet Reduces HO-1 to Promote T Cell-Mediated Tumor Cytotoxicity.

    Science.gov (United States)

    Di Biase, Stefano; Lee, Changhan; Brandhorst, Sebastian; Manes, Brianna; Buono, Roberta; Cheng, Chia-Wei; Cacciottolo, Mafalda; Martin-Montalvo, Alejandro; de Cabo, Rafael; Wei, Min; Morgan, Todd E; Longo, Valter D

    2016-07-11

    Immune-based interventions are promising strategies to achieve long-term cancer-free survival. Fasting was previously shown to differentially sensitize tumors to chemotherapy while protecting normal cells, including hematopoietic stem and immune cells, from its toxic side effects. Here, we show that the combination of chemotherapy and a fasting-mimicking diet (FMD) increases the levels of bone marrow common lymphoid progenitor cells and cytotoxic CD8(+) tumor-infiltrating lymphocytes (TILs), leading to a major delay in breast cancer and melanoma progression. In breast tumors, this effect is partially mediated by the downregulation of the stress-responsive enzyme heme oxygenase-1 (HO-1). These data indicate that FMD cycles combined with chemotherapy can enhance T cell-dependent targeted killing of cancer cells both by stimulating the hematopoietic system and by enhancing CD8(+)-dependent tumor cytotoxicity. PMID:27411588

  17. Bile acid effects are mediated by ATP release and purinergic signalling in exocrine pancreatic cells

    DEFF Research Database (Denmark)

    Kowal, Justyna Magdalena; Haanes, Kristian Agmund; Christensen, Nynne;

    2015-01-01

    BACKGROUND: In many cells, bile acids (BAs) have a multitude of effects, some of which may be mediated by specific receptors such the TGR5 or FXR receptors. In pancreas systemic BAs, as well as intra-ductal BAs from bile reflux, can affect pancreatic secretion. Extracellular ATP and purinergic......) and duct cells (Capan-1). Taurine and glycine conjugated forms of CDCA had smaller effects on ATP release in Capan-1 cells. In duct monolayers, CDCA stimulated ATP release mainly from the luminal membrane; the releasing mechanisms involved both vesicular and non-vesicular secretion pathways. Duct cells...... increase [Ca(2+)]i. The TGR5 receptor is not involved in these processes but can play a protective role at high intracellular Ca(2+) conditions. We propose that purinergic signalling could be taken into consideration in other cells/organs, and thereby potentially explain some of the multifaceted effects...

  18. IFN-α primes T- and NK-cells for IL-15-mediated signaling and cytotoxicity

    DEFF Research Database (Denmark)

    Hansen, Mikkel L; Woetmann, Anders; Krejsgaard, Thorbjørn;

    2011-01-01

    -α fosters the production of IL-15, which plays a pivotal role in the development, survival and function of NK cells and recruitment and activation of T cells. Since these two cytokines exert overlapping functions during infections, this investigation was undertaken to study the priming effect of IFN......-α on the effect of IL-15 on human T and NK cells. We show that IFN-α induces an increased expression of IL-15Rα in human activated peripheral T cells, and in CD8(+) and CD4(+) T-cell lines. Functionally, the IFN-α-enhanced IL-15Rα expression resulted in an enhanced IL-15-mediated phosphorylation of STAT5 and STAT...

  19. Role of paracrine factors in stem and progenitor cell mediated cardiac repair and tissue fibrosis

    Directory of Open Access Journals (Sweden)

    Burchfield Jana S

    2008-10-01

    Full Text Available Abstract A new era has begun in the treatment of ischemic disease and heart failure. With the discovery that stem cells from diverse organs and tissues, including bone marrow, adipose tissue, umbilical cord blood, and vessel wall, have the potential to improve cardiac function beyond that of conventional pharmacological therapy comes a new field of research aiming at understanding the precise mechanisms of stem cell-mediated cardiac repair. Not only will it be important to determine the most efficacious cell population for cardiac repair, but also whether overlapping, common mechanisms exist. Increasing evidence suggests that one mechanism of action by which cells provide tissue protection and repair may involve paracrine factors, including cytokines and growth factors, released from transplanted stem cells into the surrounding tissue. These paracrine factors have the potential to directly modify the healing process in the heart, including neovascularization, cardiac myocyte apoptosis, inflammation, fibrosis, contractility, bioenergetics, and endogenous repair.

  20. Role of apoptosis and necrosis in cell death induced by nanoparticle-mediated photothermal therapy

    Energy Technology Data Exchange (ETDEWEB)

    Pattani, Varun P., E-mail: varun.pattani@utexas.edu; Shah, Jay; Atalis, Alexandra; Sharma, Anirudh; Tunnell, James W. [The University of Texas at Austin, Department of Biomedical Engineering (United States)

    2015-01-15

    Current cancer therapies can cause significant collateral damage due to a lack of specificity and sensitivity. Therefore, we explored the cell death pathway response to gold nanorod (GNR)-mediated photothermal therapy as a highly specific cancer therapeutic to understand the role of apoptosis and necrosis during intense localized heating. By developing this, we can optimize photothermal therapy to induce a maximum of ‘clean’ cell death pathways, namely apoptosis, thereby reducing external damage. GNRs were targeted to several subcellular localizations within colorectal tumor cells in vitro, and the cell death pathways were quantitatively analyzed after photothermal therapy using flow cytometry. In this study, we found that the cell death response to photothermal therapy was dependent on the GNR localization. Furthermore, we demonstrated that nanorods targeted to the perinuclear region irradiated at 37.5 W/cm{sup 2} laser fluence rate led to maximum cell destruction with the ‘cleaner’ method of apoptosis, at similar percentages as other anti-cancer targeted therapies. We believe that this indicates the therapeutic potential for GNR-mediated photothermal therapy to treat cancer effectively without causing damage to surrounding tissue.

  1. STAT6 Mediates Interleukin-4 Growth Inhibition in Human Breast Cancer Cells

    Directory of Open Access Journals (Sweden)

    Jennifer L. Gooch

    2002-01-01

    Full Text Available In addition to acting as a hematopoietic growth factor, interleukin-4 (IL-4 inhibits growth of some transformed cells in vitro and in vivo. In this study, we show that insulin receptor substrate (IRS-1, IRS-2, and signal transducer and activator of transcription 6 (STAT6 are phosphorylated following IL-4 treatment in MCF-7 breast cancer cells. STAT6 DNA binding is enhanced by IL-4 treatment. STAT6 activation occurs even after IRS-1 depletion, suggesting the two pathways are independent. To examine the role of STAT6 in IL-4-mediated growth inhibition and apoptosis, a fulllength STAT6 cDNA was transfected into MCF-7 cells. Transient overexpression of STAT6 resulted in both cytoplasmic and nuclear expression of the protein, increased DNA binding in response to IL-4, and increased transactivation of an IL-4 responsive promoter. In STAT6-transfected cells, basal proliferation was reduced whereas apoptosis was increased. Finally, stable expression of STAT6 resulted in reduced foci formation compared to vector-transfected cells alone. These results suggest STAT6 is required for IL-4mediated growth inhibition and induction of apoptosis in human breast cancer cells.

  2. Contact-mediated and humoral communication between vascular endothelial and smooth muscle cells in vitro

    International Nuclear Information System (INIS)

    Vascular endothelial cells (EC) and smooth muscle cells (SMC) co-exist in close apposition to each other in all blood vessels except capillaries. Investigations of the metabolic interactions that may occur between these cells are essential to an understanding of vascular homeostasis and the pathogenesis of atherosclerosis. The authors have developed two in vitro models of co-temporal vascular cell communication. The first facilitates reversible microcarrier-mediated gap junctional communication between EC and SMC monolayers. When either EC or SMC were prelabelled with 3H-uridine, intracellular nucleotide rapidly transferred across the region of heterocellular attachment to the complementary cell population. Cytoplasmic continuity between EC and SMC allowed metabolic cooperation via ions and small molecules (<1.5 KD). Thus, vascular reactivity, particularly in the microcirculation where myoendothelial gap junctions have been observed, may involve cytoplasmic second messengers transported from EC to SMC. In the second model, humoral communication was established between separated cultures of EC and SMC which shared the same culture medium. Endothelial-specific stimulation of SMC growth and lipoprotein metabolism via soluble factors was demonstrated. Two mechanisms of stimulation of SMC lipoprotein metabolism were identified; one endothelial derived mitogen-dependent, the other mitogen-independent which was mediated via low molecular weight endothelial cell products

  3. LMTK2-mediated phosphorylation regulates CFTR endocytosis in human airway epithelial cells.

    Science.gov (United States)

    Luz, Simão; Cihil, Kristine M; Brautigan, David L; Amaral, Margarida D; Farinha, Carlos M; Swiatecka-Urban, Agnieszka

    2014-05-23

    Cystic fibrosis transmembrane conductance regulator (CFTR) is a Cl(-)-selective ion channel expressed in fluid-transporting epithelia. Lemur tyrosine kinase 2 (LMTK2) is a transmembrane protein with serine and threonine but not tyrosine kinase activity. Previous work identified CFTR as an in vitro substrate of LMTK2, suggesting a functional link. Here we demonstrate that LMTK2 co-immunoprecipitates with CFTR and phosphorylates CFTR-Ser(737) in human airway epithelial cells. LMTK2 knockdown or expression of inactive LMTK2 kinase domain increases cell surface density of CFTR by attenuating its endocytosis in human airway epithelial cells. Moreover, LMTK2 knockdown increases Cl(-) secretion mediated by the wild-type and rescued ΔF508-CFTR. Compared with the wild-type CFTR, the phosphorylation-deficient mutant CFTR-S737A shows increased cell surface density and decreased endocytosis. These results demonstrate a novel mechanism of the phospho-dependent inhibitory effect of CFTR-Ser(737) mediated by LMTK2 via endocytosis and inhibition of the cell surface density of CFTR Cl(-) channels. These data indicate that targeting LMTK2 may increase the cell surface density of CFTR Cl(-) channels and improve stability of pharmacologically rescued ΔF508-CFTR in patients with cystic fibrosis.

  4. Sensitive hepatocyte-mediated assay for the metabolism of nitrosamines to mutagens for mammalian cells

    Energy Technology Data Exchange (ETDEWEB)

    Jones, C.A.; Huberman, E.

    1980-02-01

    A sensitive cell-mediated assay has been developed for testing mutagenesis in Chinese hamster V79 cells by carcinogenic nitrosamines. Mutations were characterized by resistance to ouabian and 6-thioguanine. Since V79 cells do not metabolize nitrosamines, mutagenesis in the V79 cells was tested in the presence of primary hepatocytes capable of metabolizing nitrosamines. The hepatocytes were isolated after collagenase and hyaluronidase digestion of liver slices. All seven liver carcinogens of the nine tested nitrosamines exhibited a mutagenic response in this cell-mediated assay. The potent liver carcinogens nitrosodimethylamine, nitrosodiethylamine, nitrosoethylmethylamine, and nitrosodipropylamine could be detected with doses as low as 1 ..mu..m. The noncarcinogenic nitrosodiphenylamine was not mutagenic. Nitrosomethoxymethylamine was the only nitrosamine that exhibited mutagenic activity in the absence of hepatocytes, and this activity was diminished in the presence of hepatocytes. It is suggested that the use of hepatocytes prepared by the slicing method for carcinogen metabolism and mutable V79 cells offers a highly sensitive assay for determining the mutagenic potential of carcinogenic nitrosamines and probably of other classes of hazardous chemicals occurring in the environment.

  5. Tumor-derived endothelial cells exhibit aberrant Rho-mediated mechanosensing and abnormal angiogenesis in vitro.

    Science.gov (United States)

    Ghosh, Kaustabh; Thodeti, Charles K; Dudley, Andrew C; Mammoto, Akiko; Klagsbrun, Michael; Ingber, Donald E

    2008-08-12

    Tumor blood vessels exhibit abnormal structure and function that cause disturbed blood flow and high interstitial pressure, which impair delivery of anti-cancer agents. Past efforts to normalize the tumor vasculature have focused on inhibition of soluble angiogenic factors, such as VEGF; however, capillary endothelial (CE) cell growth and differentiation during angiogenesis are also influenced by mechanical forces conveyed by the extracellular matrix (ECM). Here, we explored the possibility that tumor CE cells form abnormal vessels because they lose their ability to sense and respond to these physical cues. These studies reveal that, in contrast to normal CE cells, tumor-derived CE cells fail to reorient their actin cytoskeleton when exposed to uniaxial cyclic strain, exhibit distinct shape sensitivity to variations in ECM elasticity, exert greater traction force, and display an enhanced ability to retract flexible ECM substrates and reorganize into tubular networks in vitro. These behaviors correlate with a constitutively high level of baseline activity of the small GTPase Rho and its downstream effector, Rho-associated kinase (ROCK). Moreover, decreasing Rho-mediated tension by using the ROCK inhibitor, Y27632, can reprogram the tumor CE cells so that they normalize their reorientation response to uniaxial cyclic strain and their ability to form tubular networks on ECM gels. Abnormal Rho-mediated sensing of mechanical cues in the tumor microenvironment may therefore contribute to the aberrant behaviors of tumor CE cells that result in the development of structural abnormalities in the cancer microvasculature.

  6. Fibronectin-integrin mediated signaling in human cervical cancer cells (SiHa).

    Science.gov (United States)

    Maity, Gargi; Fahreen, Shabana; Banerji, Aniruddha; Roy Choudhury, Paromita; Sen, Triparna; Dutta, Anindita; Chatterjee, Amitava

    2010-03-01

    Interaction between cell surface integrin receptors and extracellular matrix (ECM) components plays an important role in cell survival, proliferation, and migration, including tumor development and invasion of tumor cells. Matrix metalloproteinases (MMPs) are a family of metalloproteinases capable of digesting ECM components and are important molecules for cell migration. Binding of ECM to integrins initiates cascades of cell signaling events modulating expression and activity of different MMPs. The aim of this study is to investigate fibronectin-integrin-mediated signaling and modulation of MMPs. Our findings indicated that culture of human cervical cancer cell (SiHa) on fibronectin-coated surface perhaps sends signals via fibronectin-integrin-mediated signaling pathways recruiting focal adhesion kinase (FAK) extracellular signal regulated kinase (ERK), phosphatidyl inositol 3 kinase (PI-3K), integrin-linked kinase (ILK), nuclear factor-kappa B (NF-kappaB), and modulates expression and activation of mainly pro-MMP-9, and moderately pro-MMP-2 in serum-free culture medium.

  7. Matrine inhibits proliferation and induces apoptosis via BID-mediated mitochondrial pathway in esophageal cancer cells.

    Science.gov (United States)

    Wang, Qiao; Du, Haoxin; Geng, Guojun; Zhou, Huan; Xu, Minying; Cao, Hanwei; Zhang, Bing; Song, Gang; Hu, Tianhui

    2014-05-01

    Matrine, as a member of Sophora family, is an alkaloid found in plants, and produces plethora pharmacological effects, including anti-cancer effects. However, the mechanism involved remains largely unknown. This study is conducted to investigate the anti-cancer mechanisms of matrine in human esophageal cancer in vitro and in vivo. In human esophageal cancer cell Eca-109, matrine significantly decreased the cell viability in a dose-dependent manner, and induced apoptosis as well as cell cycle arrest in G0/G1 phase by up-regulation of P53 and P21. The expression of several apoptosis-related proteins in cells and tumor tissues were evaluated by Western blot analysis. We found that matrine induced cell apoptosis by down-regulation of the ratio of BCL-2/BID and increasing activation of caspase-9. Further studies indicated that matrine induced apoptosis of Eca-109 was through the mitochondria-mediated internal pathway, but not by death receptor-mediated extrinsic apoptotic pathway, which was confirmed by the fact that Bid translocated from the nucleus to mitochondria during the process of the apoptosis induced by matrine. In vivo study found that matrine effectively inhibited the tumor formation of Eca-109 cells in nude mice. Our study suggests that matrine could serve as a potential novel agent from natural products to treat esophageal cancer.

  8. Mitochondria-Mediated Protein Regulation Mechanism of Polymorphs-Dependent Inhibition of Nanoselenium on Cancer Cells.

    Science.gov (United States)

    Wang, Ge; Guo, Yuming; Yang, Gai; Yang, Lin; Ma, Xiaoming; Wang, Kui; Zhu, Lin; Sun, Jiaojiao; Wang, Xiaobing; Zhang, Hua

    2016-01-01

    The present study was (i) to prepare two types of selenium nanoparticles, namely an amorphous form of selenium quantum dots (A-SeQDs) and a crystalline form of selenium quantum dots (C-SeQDs); and (ii) to investigate the nano-bio interactions of A-SeQDs and C-SeQDs in MCF-7, HepG2, HeLa, NIH/3T3, L929 cells and BRL-3A cells. It was found that A-SeQDs could induce the mitochondria-mediated apoptosis, necrosis and death of cells, while C-SeQDs had much weaker effects. This polymorphs-dependent anti-proliferative activity of nano-selenium was scarcely reported. Further investigation demonstrated that A-SeQDs could differentially regulate 61 proteins and several pathways related to stress response, protein synthesis, cell migration and cell cycle, including "p38 MAPK Signaling", "p53 Signaling", "14-3-3-mediated Signaling", "p70S6K Signaling" and "Protein Ubiquitination Pathway". This was the first report to demonstrate the involvement of protein synthesis and post-translational modification pathways in the anti-proliferative activity associated with NMs. Compared with previously fragmentary studies, this study use a nanomics approach combining bioinformatics and proteomics to systematically investigate the nano-bio interactions of selenium nanoparticles in cancer cells. PMID:27514819

  9. Mitochondria-Mediated Protein Regulation Mechanism of Polymorphs-Dependent Inhibition of Nanoselenium on Cancer Cells

    Science.gov (United States)

    Wang, Ge; Guo, Yuming; Yang, Gai; Yang, Lin; Ma, Xiaoming; Wang, Kui; Zhu, Lin; Sun, Jiaojiao; Wang, Xiaobing; Zhang, Hua

    2016-08-01

    The present study was (i) to prepare two types of selenium nanoparticles, namely an amorphous form of selenium quantum dots (A-SeQDs) and a crystalline form of selenium quantum dots (C-SeQDs); and (ii) to investigate the nano-bio interactions of A-SeQDs and C-SeQDs in MCF-7, HepG2, HeLa, NIH/3T3, L929 cells and BRL-3A cells. It was found that A-SeQDs could induce the mitochondria-mediated apoptosis, necrosis and death of cells, while C-SeQDs had much weaker effects. This polymorphs-dependent anti-proliferative activity of nano-selenium was scarcely reported. Further investigation demonstrated that A-SeQDs could differentially regulate 61 proteins and several pathways related to stress response, protein synthesis, cell migration and cell cycle, including “p38 MAPK Signaling”, “p53 Signaling”, “14-3-3-mediated Signaling”, “p70S6K Signaling” and “Protein Ubiquitination Pathway”. This was the first report to demonstrate the involvement of protein synthesis and post-translational modification pathways in the anti-proliferative activity associated with NMs. Compared with previously fragmentary studies, this study use a nanomics approach combining bioinformatics and proteomics to systematically investigate the nano-bio interactions of selenium nanoparticles in cancer cells.

  10. Signaling pathways involved in megakaryocyte-mediated proliferation of osteoblast lineage cells.

    Science.gov (United States)

    Cheng, Ying-Hua; Streicher, Drew A; Waning, David L; Chitteti, Brahmananda R; Gerard-O'Riley, Rita; Horowitz, Mark C; Bidwell, Joseph P; Pavalko, Fredrick M; Srour, Edward F; Mayo, Lindsey D; Kacena, Melissa A

    2015-03-01

    Recent studies suggest that megakaryocytes (MKs) may play a significant role in skeletal homeostasis, as evident by the occurrence of osteosclerosis in multiple MK related diseases (Lennert et al., 1975; Thiele et al., 1999; Chagraoui et al., 2006). We previously reported a novel interaction whereby MKs enhanced proliferation of osteoblast lineage/osteoprogenitor cells (OBs) by a mechanism requiring direct cell-cell contact. However, the signal transduction pathways and the downstream effector molecules involved in this process have not been characterized. Here we show that MKs contact with OBs, via beta1 integrin, activate the p38/MAPKAPK2/p90RSK kinase cascade in the bone cells, which causes Mdm2 to neutralizes p53/Rb-mediated check point and allows progression through the G1/S. Interestingly, activation of MAPK (ERK1/2) and AKT, collateral pathways that regulate the cell cycle, remained unchanged with MK stimulation of OBs. The MK-to-OB signaling ultimately results in significant increases in the expression of c-fos and cyclin A, necessary for sustaining the OB proliferation. Overall, our findings show that OBs respond to the presence of MKs, in part, via an integrin-mediated signaling mechanism, activating a novel response axis that de-represses cell cycle activity. Understanding the mechanisms by which MKs enhance OB proliferation will facilitate the development of novel anabolic therapies to treat bone loss associated with osteoporosis and other bone-related diseases. PMID:25160801

  11. Imidacloprid inhibits IgE-mediated RBL-2H3 cell degranulation and passive cutaneous anaphylaxis

    Science.gov (United States)

    Shi, Linbo; Zou, Li; Gao, Jinyan; Xu, Huaing; Shi, Xiaoyun

    2016-01-01

    Background Imidacloprid has been commonly used as a pesticide for crop protection and acts as nicotinic acetylcholine receptor agonists. Little information about the relationship between imidacloprid and allergy is available. Objective This study aims to examine the effects of imidacoprid on IgE-mediated mast cell activation. Methods The rat basophilic leukemia cell line RBL-2H3 (RBL-2H3 cells) were treated with 10-3 – 10-12 mol/L imidacloprid, followed by measuring the mediator production, influx of Ca2+ in IgE-activated RBL-2H3 cells, and the possible effects of imidacoprid on anti-dinitrophenyl IgE-induced passive cutaneous anaphylaxis (PCA). Results It was shown that imidacoprid suppressed the production of histamine, β-hexosaminidase, leukotriene C4, interleukin-6, tumor necrosis factor-α, and Ca2+ mobilization in IgE-activated RBL-2H3 cells and decreased vascular extravasation in IgE-induced PCA. Conclusion It is the first time to show that imidacloprid suppressed the activation of RBL-2H3 cells. PMID:27803884

  12. Autophagy and cellular senescence mediated by Sox2 suppress malignancy of cancer cells.

    Directory of Open Access Journals (Sweden)

    Yong-Yeon Cho

    Full Text Available Autophagy is a critical cellular process required for maintaining cellular homeostasis in health and disease states, but the molecular mechanisms and impact of autophagy on cancer is not fully understood. Here, we found that Sox2, a key transcription factor in the regulation of the "stemness" of embryonic stem cells and induced-pluripotent stem cells, strongly induced autophagic phenomena, including intracellular vacuole formation and lysosomal activation in colon cancer cells. The activation occurred through Sox2-mediated ATG10 gene expression and resulted in the inhibition of cell proliferation and anchorage-independent colony growth ex vivo and tumor growth in vivo. Further, we found that Sox2-induced-autophagy enhanced cellular senescence by up-regulating tumor suppressors or senescence factors, including p16(INK4a, p21 and phosphorylated p53 (Ser15. Notably, knockdown of ATG10 in Sox2-expressing colon cancer cells restored cancer cell properties. Taken together, our results demonstrated that regulation of autophagy mediated by Sox2 is a mechanism-driven novel strategy to treat human colon cancers.

  13. Lentiviral Vector Mediated Claudin1 Silencing Inhibits Epithelial to Mesenchymal Transition in Breast Cancer Cells

    Directory of Open Access Journals (Sweden)

    Xianqi Zhao

    2015-06-01

    Full Text Available Breast cancer has a high incidence and mortality rate worldwide. Several viral vectors including lentiviral, adenoviral and adeno-associated viral vectors have been used in gene therapy for various forms of human cancer, and have shown promising effects in controlling tumor development. Claudin1 (CLDN1 is a member of the tetraspan transmembrane protein family that plays a major role in tight junctions and is associated with tumor metastasis. However, the role of CLDN1 in breast cancer is largely unexplored. In this study, we tested the therapeutic potential of silencing CLDN1 expression in two breast cancer (MDA-MB-231 and MCF7 cell lines using lentiviral vector mediated RNA interference. We found that a CLDN1 short hairpin (shRNA construct efficiently silenced CLDN1 expression in both breast cancer cell lines, and CLDN1 knockdown resulted in reduced cell proliferation, survival, migration and invasion. Furthermore, silencing CLDN1 inhibited epithelial to mesenchymal transition (EMT by upregulating the epithelial cell marker, E-cadherin, and downregulating mesenchymal markers, smooth muscle cell alpha-actin (SMA and Snai2. Our data demonstrated that lentiviral vector mediated CLDN1 RNA interference has great potential in breast cancer gene therapy by inhibiting EMT and controlling tumor cell growth.

  14. Loss of STAT3 in Lymphoma Relaxes NK Cell-Mediated Tumor Surveillance

    Directory of Open Access Journals (Sweden)

    Eva Maria Putz

    2014-01-01

    Full Text Available The transcription factors and proto-oncogenes STAT3 and STAT5 are highly activated in hematological malignancies and represent promising therapeutic targets. Whereas the importance of STAT5 as tumor promoter is beyond doubt, the role of STAT3 in hematological cancers is less well understood. Both, enforced as well as attenuated expression of STAT3 were reported in hematopoietic malignancies. Recent evidence implicates STAT3 as key player for tumor immune surveillance as it both mediates the production of and response to inflammatory cytokines. Here we investigated the effects of STAT3 deletion in a BCR/ABL-induced lymphoma model, which is tightly controlled by natural killer (NK cells in vivo. Upon STAT3 deletion tumor growth is significantly enhanced when compared to STAT3-expressing controls. The increased tumor size upon loss of STAT3 was accompanied by reduced NK cell infiltration and decreased levels of the cytokine IFN-γ and the chemokine RANTES. Upon transplantation into NK cell-deficient mice differences in lymphoma size were abolished indicating that STAT3 expression in the tumor cells controls NK cell-dependent tumor surveillance. Our findings indicate that STAT3 inhibition in lymphoma patients will impair NK cell-mediated tumor surveillance, which needs to be taken into account when testing STAT3 inhibitors in preclinical or clinical trials.

  15. Loss of STAT3 in Lymphoma Relaxes NK Cell-Mediated Tumor Surveillance

    Energy Technology Data Exchange (ETDEWEB)

    Putz, Eva Maria [Institute of Pharmacology and Toxicology, University of Veterinary Medicine, Veterinaerplatz 1, Vienna 1210 (Austria); Hoelzl, Maria Agnes [Institute of Pharmacology, Center for Physiology and Pharmacology, Medical University of Vienna (MUV), Waehringer Strasse 13A, Vienna 1090 (Austria); Baeck, Julia [Institute of Pharmacology and Toxicology, University of Veterinary Medicine, Veterinaerplatz 1, Vienna 1210 (Austria); Bago-Horvath, Zsuzsanna [Institute of Pharmacology and Toxicology, University of Veterinary Medicine, Veterinaerplatz 1, Vienna 1210 (Austria); Clinical Institute of Pathology, Medical University of Vienna (MUV), Waehringer Gürtel 18-20, Vienna 1090 (Austria); Schuster, Christian [Institute of Pharmacology, Center for Physiology and Pharmacology, Medical University of Vienna (MUV), Waehringer Strasse 13A, Vienna 1090 (Austria); Reichholf, Brian [Institute of Pharmacology and Toxicology, University of Veterinary Medicine, Veterinaerplatz 1, Vienna 1210 (Austria); Kern, Daniela; Aberger, Fritz [Department of Molecular Biology, University of Salzburg, Hellbrunnerstrasse 34, Salzburg 5020 (Austria); Sexl, Veronika; Hoelbl-Kovacic, Andrea, E-mail: andrea.hoelbl@vetmeduni.ac.at [Institute of Pharmacology and Toxicology, University of Veterinary Medicine, Veterinaerplatz 1, Vienna 1210 (Austria)

    2014-01-27

    The transcription factors and proto-oncogenes STAT3 and STAT5 are highly activated in hematological malignancies and represent promising therapeutic targets. Whereas the importance of STAT5 as tumor promoter is beyond doubt, the role of STAT3 in hematological cancers is less well understood. Both, enforced as well as attenuated expression of STAT3 were reported in hematopoietic malignancies. Recent evidence implicates STAT3 as key player for tumor immune surveillance as it both mediates the production of and response to inflammatory cytokines. Here we investigated the effects of STAT3 deletion in a BCR/ABL-induced lymphoma model, which is tightly controlled by natural killer (NK) cells in vivo. Upon STAT3 deletion tumor growth is significantly enhanced when compared to STAT3-expressing controls. The increased tumor size upon loss of STAT3 was accompanied by reduced NK cell infiltration and decreased levels of the cytokine IFN-γ and the chemokine RANTES. Upon transplantation into NK cell-deficient mice differences in lymphoma size were abolished indicating that STAT3 expression in the tumor cells controls NK cell-dependent tumor surveillance. Our findings indicate that STAT3 inhibition in lymphoma patients will impair NK cell-mediated tumor surveillance, which needs to be taken into account when testing STAT3 inhibitors in preclinical or clinical trials.

  16. Electricity production from xylose using a mediator-less microbial fuel cell

    DEFF Research Database (Denmark)

    Huang, Liping; Zeng, Raymond Jianxiong; Angelidaki, Irini

    2008-01-01

    Electricity generation integrated with xylose degradation was investigated in a two-chamber mediator-less microbial fuel cell (MFC). Voltage output followed saturation kinetics as a function of xylose concentration for concentration below 9.7 mM, with a predicted maximum of 86 mV (6.3 mW m(-2) or...... in the MFC for electricity production. Comparatively higher electricity generation and coulombic efficiency can be obtained by adjusting initial xylose concentration and applying stirring in the anode chamber.......Electricity generation integrated with xylose degradation was investigated in a two-chamber mediator-less microbial fuel cell (MFC). Voltage output followed saturation kinetics as a function of xylose concentration for concentration below 9.7 mM, with a predicted maximum of 86 mV (6.3 mW m(-2...

  17. Mediator-assisted Simultaneous probing of Cytosolic and Mitochondrial Redox activity in living cells

    DEFF Research Database (Denmark)

    Heiskanen, Arto; Spegel, Christer; Kostesha, Natalie;

    2009-01-01

    ferricyanide-menadione double mediator system to study the effect of dicoumarol, an inhibitor of cytosolic and mitochondrial oxidoreductases and an uncoupler of the electron transport chain. Evaluation of the role of NAD(P)H-producing pathways in mediating biological effects is facilitated by introducing...... either fructose or glucose as the carbon source, yielding either NADH or NADPH through the glycolytic or pen-rose phosphate pathway, respectively. Respiratory noncompetent cells show greater inhibition of cytosolic menadione-reducing enzymes when NADH rather than NADPH is produced. Spectrophotometric in...... vitro assays show no difference between the cofactors. Respiratory competent cells show cytosolic inhibition only when NADPH is produced, whereas production of NADH reveals uncoupling at low dicoumarol concentrations and inhibition of complexes III and IV at higher concentrations. Spectrophotometric...

  18. STAT3 interrupts ATR-Chk1 signaling to allow oncovirus-mediated cell proliferation.

    Science.gov (United States)

    Koganti, Siva; Hui-Yuen, Joyce; McAllister, Shane; Gardner, Benjamin; Grasser, Friedrich; Palendira, Umaimainthan; Tangye, Stuart G; Freeman, Alexandra F; Bhaduri-McIntosh, Sumita

    2014-04-01

    DNA damage response (DDR) is a signaling network that senses DNA damage and activates response pathways to coordinate cell-cycle progression and DNA repair. Thus, DDR is critical for maintenance of genome stability, and presents a powerful defense against tumorigenesis. Therefore, to drive cell-proliferation and transformation, viral and cellular oncogenes need to circumvent DDR-induced cell-cycle checkpoints. Unlike in hereditary cancers, mechanisms that attenuate DDR and disrupt cell-cycle checkpoints in sporadic cancers are not well understood. Using Epstein-Barr virus (EBV) as a source of oncogenes, we have previously shown that EBV-driven cell proliferation requires the cellular transcription factor STAT3. EBV infection is rapidly followed by activation and increased expression of STAT3, which mediates relaxation of the intra-S phase cell-cycle checkpoint; this facilitates viral oncogene-driven cell proliferation. We now show that replication stress-associated DNA damage, which results from EBV infection, is detected by DDR. However, signaling downstream of ATR is impaired by STAT3, leading to relaxation of the intra-S phase checkpoint. We find that STAT3 interrupts ATR-to-Chk1 signaling by promoting loss of Claspin, a protein that assists ATR to phosphorylate Chk1. This loss of Claspin which ultimately facilitates cell proliferation is mediated by caspase 7, a protein that typically promotes cell death. Our findings demonstrate how STAT3, which is constitutively active in many human cancers, suppresses DDR, fundamental to tumorigenesis. This newly recognized role for STAT3 in attenuation of DDR, discovered in the context of EBV infection, is of broad interest as the biology of cell proliferation is central to both health and disease.

  19. Cis-hydroxyproline-induced inhibition of pancreatic cancer cell growth is mediated by endoplasmic reticulum stress

    Institute of Scientific and Technical Information of China (English)

    Christoph Mueller; Joerg Emmrich; Robert Jaster; Dagmar Braun; Stefan Liebe; Gisela Sparmann

    2006-01-01

    AIM: To investigate the biological effects of cishydroxyproline (CHP) on the rat pancreatic carcinoma cell line DSL6A, and to examine the underlying molecular mechanisms.METHODS: The effect of CHP on DSL6A cell proliferation was assessed by using BrdU incorporation. The expression of focal adhesion kinase (FAK) was characterized by Western blotting and immunofluorescence.Induction of endoplasmic reticulum (ER) stress was investigated by using RT-PCR and Western blotting for the glucose-related protein-78 (GRP78) and growth arrest and DNA inducible gene (GADD153). Cell viability was determined through measuring the metabolic activity based on the reduction potential of DSL6A cells. Apoptosis was analyzed by detection of caspase-3 activation and cleavage of poly(ADP-ribose) polymerase (PARP) as well as DNA laddering.RESULTS: In addition to inhibition of proliferation,incubation with CHP induced proteolytic cleavage of FAK and a delocalisation of the enzyme from focal adhesions,followed by a loss of cell adherence. Simultaneously,we could show an increased expression of GRP78 and GADD153, indicating a CHP-mediated activation of the ER stress cascade in the DSL6A cell line. Prolonged incubation of DSL6A cells with CHP finally resulted in apoptotic cell death. Beside L-proline, the inhibition of intracellular proteolysis by addition of a broad spectrum protease inhibitor could abolish the effects of CHP on cellular functions and the molecular processes. In contrast, impeding the activity of apoptosis-executing caspases had no influence on CHP-mediated cell damage.CONCLUSION: Our data suggest that the initiation of ER stress machinery by CHP leads to an activation of intracellular proteolytic processes, including caspaseindependent FAK degradation, resulting in damaging pancreatic carcinoma cells.

  20. Lentivirus-mediated gene silencing of NOB1 suppresses non-small cell lung cancer cell proliferation.

    Science.gov (United States)

    Huang, Weiyi; Zhong, Weiqing; Xu, Jun; Su, Benhua; Huang, Guanghui; Du, Jiajun; Liu, Qi

    2015-09-01

    NIN/RPN12 binding protein 1 (NOB1p) encoded by NOB1 has been found to be an essential factor in 26S proteasome biogenesis which participates in protein degradation. However, the functions of NOB1 in non-small cell lung cancer cells are largely unknown. In the present study, lentivirus-mediated NOB1 shRNA transfection in two non-small cell lung cancer cell lines (A549 and H1299) was accomplished, as determined by fluorescence imaging. Downregulation of NOB1 expression was confirmed by real-time PCR and western blotting. NOB1 silencing resulted in a significant decline in the proliferation and colony formation capability of non-small cell lung cancer cells. Moreover, flow cytometry showed that A549 cells were arrested in the G0/G1 phase of the cell cycle after NOB1 suppression. Furthermore, depletion of NOB1 resulted in a significant decrease in CDK4 and cyclin D1 expression. These results suggest that NOB1 may act as an important regulator in non-small cell lung cancer growth and could be a therapeutic target of non‑small cell lung cancer. PMID:26178254

  1. Polarized exocyst-mediated vesicle fusion directs intracellular lumenogenesis within the C. elegans excretory cell

    OpenAIRE

    Armenti, Stephen T.; Chan, Emily; Nance, Jeremy

    2014-01-01

    Lumenogenesis of small seamless tubes occurs through intracellular membrane growth and directed vesicle fusion events. Within the C. elegans excretory cell, which forms seamless intracellular tubes (canals) that mediate osmoregulation, lumens grow in length and diameter when vesicles fuse with the expanding lumenal surface. Here, we show that lumenal vesicle fusion depends on the small GTPase RAL-1, which localizes to vesicles and acts through the exocyst vesicle-tethering complex. Loss of ei...

  2. A46, a Benzothiophene Derived Compound, Suppresses Jak2-Mediated Pathologic Cell Growth

    OpenAIRE

    Majumder, Anurima; Magis, Andrew T.; Park, Sung O.; Figueroa, Nicholas C.; Baskin, Rebekah; Kirabo, Annet; Robert W Allan; Zhao, Zhizhuang Joe; Bisht, Kirpal S.; Keserű, György M.; Sayeski, Peter P.

    2011-01-01

    Hyperkinetic Jak2 tyrosine kinase signaling has been implicated in several hematological disorders including the myeloproliferative neoplasms (MPNs). Effective Jak2 inhibitors can thus have significant therapeutic potential. Here, using structure based virtual screening, we identified a benzothiophene derived Jak2 inhibitor named A46. We hypothesized that this compound would inhibit Jak2-V617F mediated pathologic cell growth. To test this, A46 was analyzed for its ability to i) inhibit recomb...

  3. Inhibition of Endothelin-1-Mediated Contraction of Hepatic Stellate Cells by FXR Ligand

    OpenAIRE

    Jiang Li; Ramalinga Kuruba; Annette Wilson; Xiang Gao; Yifei Zhang; Song Li

    2010-01-01

    Activation of hepatic stellate cells (HSCs) plays an important role in the development of cirrhosis through the increased production of collagen and the enhanced contractile response to vasoactive mediators such as endothelin-1 (ET-1). The farnesoid X receptor (FXR) is a member of the nuclear receptor superfamily that is highly expressed in liver, kidneys, adrenals, and intestine. FXR is also expressed in HSCs and activation of FXR in HSCs is associated with significant decreases in collagen ...

  4. Techniques to Study Specific Cell-Surface Receptor-Mediated Cellular Vitamin A Uptake

    OpenAIRE

    KAWAGUCHI, RIKI; Sun, Hui

    2010-01-01

    STRA6 is a multitransmembrane domain protein that was recently identified as the cell-surface receptor for plasma retinol binding protein (RBP), the vitamin A carrier protein in the blood. STRA6 binds to RBP with high affinity and mediates cellular uptake of vitamin A from RBP. It is not homologous to any known receptors, transporters, and channels, and it represents a new class of membrane transport protein. Consistent with the diverse physiological functions of vitamin A, STRA6 is widely ex...

  5. LRP1 in Brain Vascular Smooth Muscle Cells Mediates Local Clearance of Alzheimer's Amyloid-β

    OpenAIRE

    Kanekiyo, Takahisa; Liu, Chia-Chen; Shinohara, Mitsuru; Li, Jie; Bu, Guojun

    2012-01-01

    Impaired clearance of amyloid-β (Aβ) is a major pathogenic event for Alzheimer’s disease (AD). Aβ depositions in brain parenchyma as senile plaques and along cerebrovasculature as cerebral amyloid angiopathy (CAA) are hallmarks of AD. A major pathway that mediates brain Aβ clearance is the cerebrovascular system where Aβ is eliminated through the blood-brain barrier (BBB) and/or degraded by cerebrovascular cells along the interstitial fluid drainage pathway. An Aβ clearance receptor, the low-...

  6. Rapid elevation of sodium transport through insulin is mediated by AKT in alveolar cells

    OpenAIRE

    Mattes, Charlott; Laube, Mandy; Thome, Ulrich H.

    2014-01-01

    Abstract Alveolar fluid clearance is driven by vectorial Na+ transport and promotes postnatal lung adaptation. The effect of insulin on alveolar epithelial Na+ transport was studied in isolated alveolar cells from 18–19‐day gestational age rat fetuses. Equivalent short‐circuit currents (I SC) were measured in Ussing chambers and different kinase inhibitors were used to determine the pathway of insulin stimulation. In Western Blot measurements the activation of mediators stimulated by insulin ...

  7. Rapid elevation of sodium transport through insulin is mediated by AKT in alveolar cells

    OpenAIRE

    Mattes, Charlott; Thome, Ulrich H.

    2014-01-01

    Alveolar fluid clearance is driven by vectorial Na+ transport and promotes postnatal lung adaptation. The effect of insulin on alveolar epithelial Na+ transport was studied in isolated alveolar cells from 18–19-day gestational age rat fetuses. Equivalent short-circuit currents (ISC) were measured in Ussing chambers and different kinase inhibitors were used to determine the pathway of insulin stimulation. In Western Blot measurements the activation of mediators stimulated by ...

  8. Effects of intravenous immunoglobulins on T-cell mediated, concanavalin A-induced hepatitis in mice.

    Science.gov (United States)

    Shirin, H; Bruck, R; Aeed, H; Hershkoviz, R; Lider, O; Kenet, G; Avni, Y; Halpern, Z

    1997-12-01

    Concanavalin A (ConA) activates T lymphocytes and causes T-cell mediated hepatic injury in mice. The intravenous administration of human immunoglobulins has beneficial effects in T-cell mediated diseases such as experimental autoimmune encephalomyelitis and adjuvant arthritis. In the present study, we examined the effects of intravenous immunoglobulins in a mouse model of T-cell mediated, acute liver injury induced by concanavalin A. Balb/c mice were inoculated with 12 mg/kg concanavalin A with or without intravenous immunoglobulins at doses of 0.4, 0.6, 0.8 g/kg body wt. The serum levels of liver enzymes, tumor necrosis factor-alpha, interferon-gamma and interleukin-6 were assayed 2, 6 and 24 h after concanavalin A administration. Intravenous immunoglobulins did not prevent concanavalin A-induced hepatitis, as manifested by elevation of serum aminotransferases and histopathological evaluation. The serum levels of tumor necrosis factor-alpha in mice pretreated with immunoglobulins, measured 2 h after ConA treatment were reduced, while interferon-gamma levels measured 6 h after ConA inoculation were 5-fold higher than control levels. There was no effect of intravenous immunoglobulins on the release of interleukin 6. In conclusion, these results indicate that intravenous immunoglobulin is not effective in preventing T-cell mediated concanavalin A-induced hepatitis. The increased secretion of interferon-gamma and the incomplete suppression of tumor necrosis factor-alpha release may explain the lack of efficacy of intravenous immunoglobulin in this experimental model. PMID:9455732

  9. Role of T-cell-mediated inflammation in psoriasis: pathogenesis and targeted therapy

    OpenAIRE

    Conrad, Curdin

    2013-01-01

    Lukas Flatz, Curdin ConradDepartment of Dermatology, University Hospital of Lausanne (CHUV), Lausanne, SwitzerlandAbstract: Psoriasis is one of the most common chronic, inflammatory, T-cell-mediated autoimmune diseases. Over the past decade, increased knowledge of disease pathogenesis has fundamentally changed psoriasis treatment, with the introduction of biologics, and this has led to a multitude of improved selective targets providing potential therapeutic options. Indeed, numerous pathogen...

  10. Functional Features of Trans-differentiated Hair Cells Mediated by Atoh1 Reveals a Primordial Mechanism

    OpenAIRE

    Yang, Juanmei; Bouvron, Sonia; Lv, Ping; Chi, Fanglu; Yamoah, Ebenezer N.

    2012-01-01

    Evolution has transformed a simple ear with few vestibular maculae into a complex 3-dimensional structure consisting of nine distinct endorgans. It is debatable whether the sensory epithelia underwent progressive segregation or emerged from distinct sensory patches. To address these uncertainties we examined the morphological and functional phenotype of trans-differentiated rat hair cells to reveal their primitive or endorgan-specific origins. Additionally, it is uncertain how Atoh1-mediated ...

  11. CD4+ T cells mediate mucosal and systemic immune responses to experimental hookworm infection

    OpenAIRE

    DONDJI, B.; Sun, T.; BUNGIRO, R. D.; VERMEIRE, J. J.; HARRISON, L. M.; BIFULCO, C.; Cappello, M

    2010-01-01

    Hookworm infection is associated with anaemia and malnutrition in many resource-limited countries. Ancylostoma hookworms have previously been shown to modulate host cellular immune responses through multiple mechanisms, including reduced mitogen-mediated lymphocyte proliferation, impaired antigen presentation/processing, and relative reductions in CD4+ T cells in the spleen and mesenteric lymph nodes. Syrian hamsters were depleted of CD4+ for up to 9 days following intraperitoneal injection (...

  12. SGLT-1-mediated glucose uptake protects human intestinal epithelial cells against Giardia duodenalis-induced apoptosis

    OpenAIRE

    Yu, Linda C.H.; Huang, Ching-ying; Kuo, Wei-ting; Sayer, Heather; Turner, Jerrold R; Buret, Andre G

    2008-01-01

    Infection with Giardia duodenalis is one of the most common causes of waterborne diarrheal disease worldwide. Mechanisms of pathogenesis and host response in giardiasis remain incompletely understood. Previous studies have shown that exposure to G. duodenalis products induce apoptosis in enterocytes. We recently discovered that sodium-dependent glucose cotransporter (SGLT)-1-mediated glucose uptake modulates enterocytic cell death induced by bacterial lipopolysaccharide. The aim of this study...

  13. Vav-1 expression correlates with NFkappaB activation and CD40-mediated cell death in diffuse large B-cell lymphoma cell lines

    DEFF Research Database (Denmark)

    Hollmann, Annette; Aloyz, Raquel; Baker, Kristi;

    2010-01-01

    Diffuse large B-cell lymphoma (DLBCL) is an aggressive malignancy with a variable response to therapy. We have previously shown that DLBCL cell lines differ in their susceptibility to CD40-mediated cell death, and that resistance to CD40-targeted antibodies correlated with increased expression...... of markers of immature B-cell and absence of Vav-1 mRNA. We used gene expression profiling to investigate the mechanism of CD40 resistance in these cell lines, and found that resistance correlated with lack of Vav-1 and inability to activate NFkappaB upon CD40 ligation. Analysis of tissue microarrays of 213...

  14. Blimp-1-Dependent IL-10 Production by Tr1 Cells Regulates TNF-Mediated Tissue Pathology

    Science.gov (United States)

    Montes de Oca, Marcela; Kumar, Rajiv; de Labastida Rivera, Fabian; Amante, Fiona H; Sheel, Meru; Faleiro, Rebecca J.; Bunn, Patrick T.; Best, Shannon E.; Beattie, Lynette; Ng, Susanna S.; Edwards, Chelsea L.; Muller, Werner; Cretney, Erika; Nutt, Stephen L.; Smyth, Mark J.; Haque, Ashraful; Hill, Geoffrey R.; Sundar, Shyam; Kallies, Axel; Engwerda, Christian R.

    2016-01-01

    Tumor necrosis factor (TNF) is critical for controlling many intracellular infections, but can also contribute to inflammation. It can promote the destruction of important cell populations and trigger dramatic tissue remodeling following establishment of chronic disease. Therefore, a better understanding of TNF regulation is needed to allow pathogen control without causing or exacerbating disease. IL-10 is an important regulatory cytokine with broad activities, including the suppression of inflammation. IL-10 is produced by different immune cells; however, its regulation and function appears to be cell-specific and context-dependent. Recently, IL-10 produced by Th1 (Tr1) cells was shown to protect host tissues from inflammation induced following infection. Here, we identify a novel pathway of TNF regulation by IL-10 from Tr1 cells during parasitic infection. We report elevated Blimp-1 mRNA levels in CD4+ T cells from visceral leishmaniasis (VL) patients, and demonstrate IL-12 was essential for Blimp-1 expression and Tr1 cell development in experimental VL. Critically, we show Blimp-1-dependent IL-10 production by Tr1 cells prevents tissue damage caused by IFNγ-dependent TNF production. Therefore, we identify Blimp-1-dependent IL-10 produced by Tr1 cells as a key regulator of TNF-mediated pathology and identify Tr1 cells as potential therapeutic tools to control inflammation. PMID:26765224

  15. Tolerogenic nanoparticles inhibit T cell-mediated autoimmunity through SOCS2.

    Science.gov (United States)

    Yeste, Ada; Takenaka, Maisa C; Mascanfroni, Ivan D; Nadeau, Meghan; Kenison, Jessica E; Patel, Bonny; Tukpah, Ann-Marcia; Babon, Jenny Aurielle B; DeNicola, Megan; Kent, Sally C; Pozo, David; Quintana, Francisco J

    2016-06-21

    Type 1 diabetes (T1D) is a T cell-dependent autoimmune disease that is characterized by the destruction of insulin-producing β cells in the pancreas. The administration to patients of ex vivo-differentiated FoxP3(+) regulatory T (Treg) cells or tolerogenic dendritic cells (DCs) that promote Treg cell differentiation is considered a potential therapy for T1D; however, cell-based therapies cannot be easily translated into clinical practice. We engineered nanoparticles (NPs) to deliver both a tolerogenic molecule, the aryl hydrocarbon receptor (AhR) ligand 2-(1'H-indole-3'-carbonyl)-thiazole-4-carboxylic acid methyl ester (ITE), and the β cell antigen proinsulin (NPITE+Ins) to induce a tolerogenic phenotype in DCs and promote Treg cell generation in vivo. NPITE+Ins administration to 8-week-old nonobese diabetic mice suppressed autoimmune diabetes. NPITE+Ins induced a tolerogenic phenotype in DCs, which was characterized by a decreased ability to activate inflammatory effector T cells and was concomitant with the increased differentiation of FoxP3(+) Treg cells. The induction of a tolerogenic phenotype in DCs by NPs was mediated by the AhR-dependent induction of Socs2, which resulted in inhibition of nuclear factor κB activation and proinflammatory cytokine production (properties of tolerogenic DCs). Together, these data suggest that NPs constitute a potential tool to reestablish tolerance in T1D and potentially other autoimmune disorders.

  16. Tolerogenic nanoparticles inhibit T cell-mediated autoimmunity through SOCS2.

    Science.gov (United States)

    Yeste, Ada; Takenaka, Maisa C; Mascanfroni, Ivan D; Nadeau, Meghan; Kenison, Jessica E; Patel, Bonny; Tukpah, Ann-Marcia; Babon, Jenny Aurielle B; DeNicola, Megan; Kent, Sally C; Pozo, David; Quintana, Francisco J

    2016-01-01

    Type 1 diabetes (T1D) is a T cell-dependent autoimmune disease that is characterized by the destruction of insulin-producing β cells in the pancreas. The administration to patients of ex vivo-differentiated FoxP3(+) regulatory T (Treg) cells or tolerogenic dendritic cells (DCs) that promote Treg cell differentiation is considered a potential therapy for T1D; however, cell-based therapies cannot be easily translated into clinical practice. We engineered nanoparticles (NPs) to deliver both a tolerogenic molecule, the aryl hydrocarbon receptor (AhR) ligand 2-(1'H-indole-3'-carbonyl)-thiazole-4-carboxylic acid methyl ester (ITE), and the β cell antigen proinsulin (NPITE+Ins) to induce a tolerogenic phenotype in DCs and promote Treg cell generation in vivo. NPITE+Ins administration to 8-week-old nonobese diabetic mice suppressed autoimmune diabetes. NPITE+Ins induced a tolerogenic phenotype in DCs, which was characterized by a decreased ability to activate inflammatory effector T cells and was concomitant with the increased differentiation of FoxP3(+) Treg cells. The induction of a tolerogenic phenotype in DCs by NPs was mediated by the AhR-dependent induction of Socs2, which resulted in inhibition of nuclear factor κB activation and proinflammatory cytokine production (properties of tolerogenic DCs). Together, these data suggest that NPs constitute a potential tool to reestablish tolerance in T1D and potentially other autoimmune disorders. PMID:27330188

  17. FGF2 mediates DNA repair in epidermoid carcinoma cells exposed to ionizing radiation

    International Nuclear Information System (INIS)

    Fibroblast growth factor 2 (FGF2) is a well-known survival factor. However, its role in DNA repair is poorly documented. The present study was designed to investigate in epidermoid carcinoma cells the potential role of FGF2 in DNA repair. The side population (SP) with cancer stem cell-like properties and the main population (MP) were isolated from human A431 squamous carcinoma cells. Radiation-induced DNA damage and repair were assessed using the alkaline comet assay. FGF2 expression was quantified by enzyme linked immunosorbent assay (ELISA). SP cells exhibited rapid repair of radiation induced DNA damage and a high constitutive level of nuclear FGF2. Blocking FGF2 signaling abrogated the rapid DNA repair. In contrast, in MP cells, a slower repair of damage was associated with low basal expression of FGF2. Moreover, the addition of exogenous FGF2 accelerated DNA repair in MP cells. When irradiated, SP cells secreted FGF2, whereas MP cells did not. FGF2 was found to mediate DNA repair in epidermoid carcinoma cells. We postulate that carcinoma stem cells would be intrinsically primed to rapidly repair DNA damage by a high constitutive level of nuclear FGF2. In contrast, the main population with a low FGF2 content exhibits a lower repair rate which can be increased by exogenous FGF2. (authors)

  18. Prolactin mediates effects of chronic psychological stress on induction of fibrofatty cells in the heart.

    Science.gov (United States)

    Song, Jiangping; Wang, Mangyuan; Chen, Xiao; Liu, Li; Chen, Liang; Song, Zhizhao; Teng, Xiao; Xing, Yong; Chen, Kai; Zhao, Kun; Hou, Jianfeng; Yang, Pingchang

    2016-01-01

    Cardiocyte apoptosis plays an important role in the pathogenesis of heart diseases. The mechanism is unclear. It is reported that prolactin (PRL) is involved in cardiac disorders. This study aims to investigate the role of PRL in mediating the psychological stress-induced fibrofatty cell differentiation in the heart. In this study, BALB/c mice were treated with a 30-day restraint stress. The heart tissue was processed by paraffin embedding and hematoxylin and eosin. The expression of Sca1 in NIH3T3 cells was assessed by cell culture, flow cytometry and Western blotting. The results showed that chronic stress induced fibrofatty cells in the mouse heart and high serum PRL levels. The induction of fibrofatty cell was mimicked by administration with recombinant PRL. The stress also induced the expression of Sca1 in the mouse heart. Exposure of NIH3T3 cells (a fibroblast cell line) to PRL in the culture enhanced the expression of stem cell antigen-1 (Sca1), phosphorylation of signal transducer and activator of transcription 3 (STAT3) and expression of adipocyte-related protein molecules, including adiponectin, fatty acid binding protein (aP2), peroxisome proliferator activated receptor-g (PPARg) and CCAAT/enhancer binding protein (C/EBP)α, in the cells. We conclude that psychological stress-derived PRL induces fibroblasts to differentiate into fibrofatty cells in the heart.

  19. RNA interference-mediated silencing of speckle-type POZ protein promotes apoptosis of renal cell cancer cells

    Directory of Open Access Journals (Sweden)

    Liu X

    2016-04-01

    Full Text Available Xiaoxia Liu, Guiling Sun, Xiuju Sun Department of Nephrology, Affiliated Hospital of Weifang Medical University, Weifang, People’s Republic of China Abstract: This study aimed to investigate the effects of silencing the speckle-type POZ protein (SPOP gene on renal cell cancer (RCC cells and to explore its possible mechanism. The A498 and ACHN RCC cells were transfected with small interference RNA (siRNA-SPOP by lipofection methods. The silencing efficiency was monitored by quantitative real-time polymerase chain reaction and Western blot. The effects of SPOP silencing on cell apoptosis, cell viability, colony formation ability, cell migration ability, and chemosensitivity to Sorafenib were assessed by flow cytometry, an MTT assay, a colony formation assay, a trans-well migration assay, and a CCK-8 assay, respectively. Its effects on the expression of several cytokines were determined by a protein microarray. Relevant signaling pathways were also analyzed. Compared with the control group, the cell apoptosis rate was significantly higher; the cell viability, the colony formation, and migration ability were significantly decreased in the siRNA-SPOP group. The protein microarray screening showed that the expression of vascular endothelial growth factor receptor, matrix metallopeptidase-9, vascular cell adhesion molecule-1, and stromal cell-derived factor-1 in the siRNA group was significantly decreased and that the expression of granulocyte–macrophage colony-stimulating factor and E-cadherin was significantly increased (P<0.05. The relevant signaling pathways were the integrin-mediated cell surface interactions pathway and extracellular matrix organization signal pathway. SPOP gene silencing induced cell apoptosis, decreased cell viability, colony formation, and migration ability, and elevated the drug sensitivity in the RCC cells. A possible mechanism is that silencing SPOP induces the differential expression of E-cadherin, vascular endothelial

  20. Cytokine-mediated regulation of plasma cell generation: IL-21 takes center stage

    Directory of Open Access Journals (Sweden)

    Stuart G Tangye

    2014-02-01

    Full Text Available During our life we are surrounded by continuous threats from a diverse range of invading pathogens. Our immune system has evolved multiple mechanisms to efficiently deal with these threats to prevent them causing disease. Differentiation of mature B cells into plasma cells (PC - the antibody (Ab secreting cells of the immune system - is critical for the generation of protective and long-lived humoral immune responses. Indeed, efficient production of antigen (Ag-specific Ab underlies the success of most currently available vaccines. The mature B cell pool is composed of several subsets, distinguished from one according to size, surface marker expression, location and Ag exposure, and they all have the capacity to differentiate into PCs. For a B cell to acquire the capacity to produce Abs, it must undergo an extensive differentiation process driven by changes in gene expression. Two broad categories of Ag exist that cause B cell activation and differentiation: T cell dependent (TD or T cell independent (TI. In addition to the B cell subset and nature of the Ag, it is important to consider the cytokine environment that also influences how B cell differentiation is achieved. Thus, while many cytokines can induce Ab secretion by B cells after activation with mimics of TD and TI stimuli in vitro, they can have different efficacies and specificities, and can often preferentially induce production of one Ig isotype over another. Here, we will provide an overview of in vitro studies (mouse and human origin that evaluated the role the different cytokines in inducing the differentiation of distinct B cell subsets to the PC lineage. We will place particular emphasis on IL-21, which has emerged as the most potent inducer of terminal B cell differentiation in humans. We will also focus on the role of IL-21 and defects in B-cell function and how these contribute to human immunopathologies such as primary immunodeficiencies and B-cell mediated autoimmune

  1. A simple and novel modification of comet assay for determination of bacteriophage mediated bacterial cell lysis.

    Science.gov (United States)

    Khairnar, Krishna; Sanmukh, Swapnil; Chandekar, Rajshree; Paunikar, Waman

    2014-07-01

    The comet assay is the widely used method for in vitro toxicity testing which is also an alternative to the use of animal models for in vivo testing. Since, its inception in 1984 by Ostling and Johansson, it is being modified frequently for a wide range of application. In spite of its wide applicability, unfortunately there is no report of its application in bacteriophages research. In this study, a novel application of comet assay for the detection of bacteriophage mediated bacterial cell lysis was described. The conventional methods in bacteriophage research for studying bacterial lysis by bacteriophages are plaque assay method. It is time consuming, laborious and costly. The lytic activity of bacteriophage devours the bacterial cell which results in the release of bacterial genomic material that gets detected by ethidium bromide staining method by the comet assay protocol. The objective of this study was to compare efficacy of comet assay with different assay used to study phage mediated bacterial lysis. The assay was performed on culture isolates (N=80 studies), modified comet assay appear to have relatively higher sensitivity and specificity than other assay. The results of the study showed that the application of comet assay can be an economical, time saving and less laborious alternative to conventional plaque assay for the detection of bacteriophage mediated bacterial cell lysis.

  2. A simple and novel modification of comet assay for determination of bacteriophage mediated bacterial cell lysis.

    Science.gov (United States)

    Khairnar, Krishna; Sanmukh, Swapnil; Chandekar, Rajshree; Paunikar, Waman

    2014-07-01

    The comet assay is the widely used method for in vitro toxicity testing which is also an alternative to the use of animal models for in vivo testing. Since, its inception in 1984 by Ostling and Johansson, it is being modified frequently for a wide range of application. In spite of its wide applicability, unfortunately there is no report of its application in bacteriophages research. In this study, a novel application of comet assay for the detection of bacteriophage mediated bacterial cell lysis was described. The conventional methods in bacteriophage research for studying bacterial lysis by bacteriophages are plaque assay method. It is time consuming, laborious and costly. The lytic activity of bacteriophage devours the bacterial cell which results in the release of bacterial genomic material that gets detected by ethidium bromide staining method by the comet assay protocol. The objective of this study was to compare efficacy of comet assay with different assay used to study phage mediated bacterial lysis. The assay was performed on culture isolates (N=80 studies), modified comet assay appear to have relatively higher sensitivity and specificity than other assay. The results of the study showed that the application of comet assay can be an economical, time saving and less laborious alternative to conventional plaque assay for the detection of bacteriophage mediated bacterial cell lysis. PMID:24681053

  3. Ceramide Production Mediates Aldosterone-Induced Human Umbilical Vein Endothelial Cell (HUVEC Damages.

    Directory of Open Access Journals (Sweden)

    Yumei Zhang

    Full Text Available Here, we studied the underlying mechanism of aldosterone (Aldo-induced vascular endothelial cell damages by focusing on ceramide. We confirmed that Aldo (at nmol/L inhibited human umbilical vein endothelial cells (HUVEC survival, and induced considerable cell apoptosis. We propose that ceramide (mainly C18 production might be responsible for Aldo-mediated damages in HUVECs. Sphingosine-1-phosphate (S1P, an anti-ceramide lipid, attenuated Aldo-induced ceramide production and following HUVEC damages. On the other hand, the glucosylceramide synthase (GCS inhibitor PDMP or the ceramide (C6 potentiated Aldo-induced HUVEC apoptosis. Eplerenone, a mineralocorticoid receptor (MR antagonist, almost completely blocked Aldo-induced C18 ceramide production and HUVEC damages. Molecularly, ceramide synthase 1 (CerS-1 is required for C18 ceramide production by Aldo. Knockdown of CerS-1 by targeted-shRNA inhibited Aldo-induced C18 ceramide production, and protected HUVECs from Aldo. Reversely, CerS-1 overexpression facilitated Aldo-induced C18 ceramide production, and potentiated HUVEC damages. Together, these results suggest that C18 ceramide production mediates Aldo-mediated HUVEC damages. MR and CerS-1 could be the two signaling molecule regulating C18 ceramide production by Aldo.

  4. Endogenous TasiRNAs mediate non-cell autonomous effects on gene regulation in Arabidopsis thaliana.

    Directory of Open Access Journals (Sweden)

    Rebecca Schwab

    Full Text Available BACKGROUND: Different classes of small RNAs (sRNAs refine the expression of numerous genes in higher eukaryotes by directing protein partners to complementary nucleic acids, where they mediate gene silencing. Plants encode a unique class of sRNAs, called trans-acting small interfering RNAs (tasiRNAs, which post-transcriptionally regulate protein-coding transcripts, as do microRNAs (miRNAs, and both sRNA classes control development through their targets. TasiRNA biogenesis requires multiple components of the siRNA pathway and also miRNAs. But while 21mer siRNAs originating from transgenes can mediate silencing across several cell layers, miRNA action seems spatially restricted to the producing or closely surrounding cells. PRINCIPAL FINDINGS: We have previously described the isolation of a genetrap reporter line for TAS3a, the major locus producing AUXIN RESPONS FACTOR (ARF-regulating tasiRNAs in the Arabidopsis shoot. Its activity is limited to the adaxial (upper side of leaf primordia, thus spatially isolated from ARF-activities, which are located in the abaxial (lower side. We show here by in situ hybridization and reporter fusions that the silencing activities of ARF-regulating tasiRNAs are indeed manifested non-cell autonomously to spatially control ARF activities. CONCLUSIONS/SIGNIFICANCE: Endogenous tasiRNAs are thus mediators of a mobile developmental signal and might provide effective gene silencing at a distance beyond the reach of most miRNAs.

  5. Reactive oxygen species do not contribute to ObgE*-mediated programmed cell death.

    Science.gov (United States)

    Dewachter, Liselot; Herpels, Pauline; Verstraeten, Natalie; Fauvart, Maarten; Michiels, Jan

    2016-01-01

    Programmed cell death (PCD) in bacteria is considered an important target for developing novel antimicrobials. Development of PCD-specific therapies requires a deeper understanding of what drives this process. We recently discovered a new mode of PCD in Escherichia coli that is triggered by expression of a mutant isoform of the essential ObgE protein, ObgE*. Our previous findings demonstrate that ObgE*-mediated cell death shares key characteristics with apoptosis in eukaryotic cells. It is well-known that reactive oxygen species (ROS) are formed during PCD in eukaryotes and play a pivotal role as signaling molecules in the progression of apoptosis. Therefore, we explored a possible role for ROS in bacterial killing by ObgE*. Using fluorescent probes and genetic reporters, we found that expression of ObgE* induces formation of ROS. Neutralizing ROS by chemical scavenging or by overproduction of ROS-neutralizing enzymes did not influence toxicity of ObgE*. Moreover, expression of ObgE* under anaerobic conditions proved to be as detrimental to bacterial viability as expression under aerobic conditions. In conclusion, ROS are byproducts of ObgE* expression that do not play a role in the execution or progression of ObgE*-mediated PCD. Targeted therapies should therefore look to exploit other aspects of ObgE*-mediated PCD. PMID:27641546

  6. T-cell-mediated drug hypersensitivity: immune mechanisms and their clinical relevance.

    Science.gov (United States)

    Yun, James; Cai, Fenfen; Lee, Frederick J; Pichler, Werner J

    2016-04-01

    T-cell-mediated drug hypersensitivity represents a significant proportion of immune mediated drug hypersensitivity reactions. In the recent years, there has been an increase in understanding the immune mechanisms behind T-cell-mediated drug hypersensitivity. According to hapten mechanism, drug specific T-cell response is stimulated by drug-protein conjugate presented on major histocompatibility complex (MHC) as it is presented as a new antigenic determinant. On the other hand, p-i concept suggests that a drug can stimulate T cells via noncovalent direct interaction with T-cell receptor and/or peptide-MHC. The drug binding site is quite variable and this leads to several different mechanisms within p-i concept. Altered peptide repertoire can be regarded as an 'atypical' subset of p-i concept since the mode of the drug binding and the binding site are essentially identical to p-i concept. However, the intracellular binding of abacavir to HLA-B(*)57:01 additionally results in alteration in peptide repertoire. Furthermore the T-cell response to altered peptide repertoire model is only shown for abacavir and HLA-B(*)57:01 and therefore it may not be generalised to other drug hypersensitivity. Danger hypothesis has been postulated to play an important role in drug hypersensitivity by providing signal 2 but its experimental data is lacking at this point in time. Furthermore, the recently described allo-immune response suggests that danger signal may be unnecessary. Finally, in view of these new understanding, the classification and the definition of type B adverse drug reaction should be revised. PMID:27141480

  7. Measurements of uranium mill tailings consolidation characteristics

    Energy Technology Data Exchange (ETDEWEB)

    Fayer, M J

    1985-02-01

    A series of experiments were conducted on uranium mill tailings from the tailings pile in Grand Junction, Colorado, to determine their consolidation characteristics. Three materials (sand, sand/slimes mix, slimes) were loaded under saturated conditions to determine their saturated consolidated behavior. During a separate experiment, samples of the slimes material were kept under a constant load while the pore pressure was increased to determine the partially saturated consolidation behavior. Results of the saturated tests compared well with published data. Sand consolidated the least, while slimes consolidated the most. As each material consolidated, the measured hydraulic conductivity decreased in a linear fashion with respect to the void ratio. Partially saturated experiments with the slimes indicated that there was little consolidation as the pore pressure was increased progressively above 7 kPa. The small amount of consolidation that did occur was only a fraction of the amount of saturated consolidation. Preliminary measurements between pore pressures of 0 and 7 kPa indicated that measurable consolidation could occur in this range of pore pressure, but only if there was no load. 13 references, 13 figures.

  8. Degradation of Epidermal Growth Factor Receptor Mediates Dasatinib-Induced Apoptosis in Head and Neck Squamous Cell Carcinoma Cells

    Directory of Open Access Journals (Sweden)

    Yu-Chin Lin

    2012-06-01

    Full Text Available Epidermal growth factor receptor (EGFR is an important oncoprotein that promotes cell growth and proliferation. Dasatinib, a bcr-abl inhibitor, has been approved clinically for the treatment of chronic myeloid leukemia and demonstrated to be effective against solid tumors in vitro through Src inhibition. Here, we disclose that EGFR degradation mediated dasatinib-induced apoptosis in head and neck squamous cell carcinoma (HNSCC cells. HNSCC cells, including Ca9-22, FaDu, HSC3, SAS, SCC-25, and UMSCC1, were treated with dasatinib, and cell viability, apoptosis, and underlying signal transduction were evaluated. Dasatinib exhibited differential sensitivities against HNSCC cells. Growth inhibition and apoptosis were correlated with its inhibition on Akt, Erk, and Bcl-2, irrespective of Src inhibition. Accordingly, we found that down-regulation of EGFR was a determinant of dasatinib sensitivity. Lysosome inhibitor reversed dasatinib-induced EGFR down-regulation, and c-cbl activity was increased by dasatinib, indicating that dasatinib-induced EGFR down-regulation might be through c-cbl-mediated lysosome degradation. Increased EGFR activation by ligand administration rescued cells from dasatinib-induced apoptosis, whereas inhibition of EGFR enhanced its apoptotic effect. Estrogen receptor α (ERα was demonstrated to play a role in Bcl-2 expression, and dasatinib inhibited ERα at the pretranslational level. ERα was associated with EGFR in dasatinib-treated HNSCC cells. Furthermore, the xenograft model showed that dasatinib inhibited HSC3 tumor growth through in vivo down-regulation of EGFR and ERα. In conclusion, degradation of EGFR is a novel mechanism responsible for dasatinib-induced apoptosis in HNSCC cells.

  9. 糖皮质激素逆转七氟烷对大鼠记忆巩固的干扰效应%Glucocorticoid reverses the impairment of memory consolidation mediated by sevoflurane

    Institute of Scientific and Technical Information of China (English)

    薛景景; 李强; 曾庆文; 薛庆生; 曹晓华; 张富军; 于布为

    2013-01-01

    -induced impairment of memory consolidation. Methods Healthy adult male Sprague-Dawley rats were randomized into eight groups: control, GC 0. 3, GC 1. 0, GC 3. 0, Sevo, Sevo + GC 0. 3, Sevo + GC 1. 0 and Sevo + GC 3. 0 groups. Immediately after a continuous multiple-trial inhibition avoidance (CMIA) training, rats in GC 0. 3 and Sevo+ GC 0.3 groups, GC 1.0 and Sevo + GC 1.0 groups, GC 3.0 and Sevo +GC 3.0 groups received peritoneal injection of glucocorticoid at 0.3 mg/kg (2 mL/kg) ,1.0 mg/kg ( 2 mL/kg), and 3.0 mg/kg(2 mL/kg), respectively; rats in Control and Sevo groups received peritoneal injection of ethanol diluent (2 mL/kg). Then the rats were exposed to sevoflurane (2.0% inspired) or air (30% oxygen and 70% nitrogen) for 2 hours. Twenty-four hours later, the CMIA retention latency and open field (OF) behavior were performed in 14 rats of each group. According to results of CMIA test, 5 rats from control, GC 3.0, Sevo and Sevo + GC 3.0 groups were sacrificed. The levels of GluFU and GluR2 subunits of α-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid receptor (AMPAR) in the hippocampus were measured. Results The memory retention latency of GC3. 0 group was significantly longer than that of control group (P0. 05). Two-factor analysis of variance showed that there were no significant differences in the levels of GluRI and GluR2 subunits among control, GC3. 0, Sevo and Sevo + GC3.0 group (all P>0.05). Conclusion Glucocorticoid can block the sevoflurane-induced impairment of memory consolidation in the hippocampus.

  10. Cells of the J774 macrophage cell line are primed for antibody-dependent cell-mediated cytotoxicity following exposure to γ-irradiation

    International Nuclear Information System (INIS)

    Activation of macrophages (M phi) for host defense against tumor cells follows a sequence of priming events followed by an initiating stimulus that results in production and release of cytotoxic molecules that mediate target cell killing. The authors have developed a model to study specific macrophage cytotoxicity in vitro utilizing a cultured murine M phi cell line, J774. Specific cytotoxicity of cultured human gastrointestinal tumor cells is achieved in the presence of murine IgG2a monoclonal antibody (mAb) 17-1-A. The ability of these cells to mediate antibody-dependent cell-mediated cytotoxicity (ADCC) is greatly enhanced following gamma-irradiation. ADCC can be demonstrated at mAb 17-1-A concentrations greater than or equal to 1 microgram/ml and effector/target cell ratios greater than or equal to 2. Exposure to doses greater than or equal to 10 Gy of gamma-irradiation increases ADCC threefold. Varying the duration from J774 M phi exposure to γ-irradiation until addition of antibody-coated target cells showed that the primed state for ADCC is stable for at least 8 days but approximately 24 hr is required for complete development of the primed state. mAb-dependent target cell death begins 8 hr after addition of mAb and labeled target cells to primed effector cells and is complete by 24 hr. Incubation of unirradiated J774 M phi effector cells with recombinant murine interferon-γ (rmIFN-γ) also results in enhanced ADCC, but the extent of target cell killing achieved is less than that following priming by γ-irradiation. Concomitant priming of γ-irradiated J774 M phi with rmIFN-γ increases the extent of ADCC. Further study of irradiated J774 cells may elucidate the molecular pathways utilized by M phi for achieving and maintaining the primed state for ADCC

  11. Baculovirus vector-mediated transfer of NIS gene into colon tumor cells for radionuclide therapy

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    AIM:To investigate the feasibility of radionuclide therapy of colon tumor cells by baculovirus vector-mediated transfer of the sodium/iodide symporter(NIS) gene.METHODS:A recombinant baculovirus plasmid carrying the NIS gene was constructed,and the viruses(BacNIS) were prepared using the Bac-to-Bac system.The infection efficiency in the colon cancer cell line SW1116 of a green fluorescent protein(GFP) expressing baculovirus(Bac-GFP) at different multiplicities of infection(MOI) with various concentrations o...

  12. Metabolic memory of ß-cells controls insulin secretion and is mediated by CaMKIIa

    OpenAIRE

    Santos, Gustavo Jorge dos; Ferreira, Sandra Mara; Ortis, Fernanda; Rezende, Luiz Fernando; Li, Chengyang; Naji, Ali; Carneiro, Everardo Magalhães; Kaestner, Klaus H.; Boschero, Antonio Carlos

    2014-01-01

    Ca2+/calmodulin-dependent protein kinase II (CaMKII) functions both in regulation of insulin secretion and neurotransmitter release through common downstream mediators. Therefore, we hypothesized that pancreatic ß-cells acquire and store the information contained in calcium pulses as a form of “metabolic memory”, just as neurons store cognitive information. To test this hypothesis, we developed a novel paradigm of pulsed exposure of ß-cells to intervals of high glucose, followed by a 24-h con...

  13. 5-Azacytidine Promotes an Inhibitory T-Cell Phenotype and Impairs Immune Mediated Antileukemic Activity

    OpenAIRE

    Thomas Stübig; Anita Badbaran; Tim Luetkens; York Hildebrandt; Djordje Atanackovic; Binder, Thomas M. C.; Boris Fehse; Nicolaus Kröger

    2014-01-01

    Demethylating agent, 5-Azacytidine (5-Aza), has been shown to be active in treatment of myeloid malignancies. 5-Aza enhances anticancer immunity, by increasing expression of tumor-associated antigens. However, the impact of 5-Aza immune responses remains poorly understood. Here, T-cell mediated tumor immunity effects of 5-Aza, are investigated in vitro and in vivo. T-cells from healthy donors were treated with 5-Aza and analyzed by qRT-PCR and flow cytometry for changes in gene expression and...

  14. Saikosaponin D Isolated from Bupleurum falcatum Inhibits Selectin-Mediated Cell Adhesion

    Directory of Open Access Journals (Sweden)

    Myoung-Jun Jang

    2014-12-01

    Full Text Available Three saikosaponins were isolated from the MeOH extract of the roots of Bupleurum falcatum L.: saikosaponins B3 (1; B4 (2; and D (3. Of the three, compound 3 inhibited the interaction of selectins (E, L, and P and THP-1 cells with IC50 values of 1.8, 3.0 and 4.3 µM, respectively. Also, the aglycone structure 4 of compound 3 showed moderate inhibitory activity on L-selectin-mediated cell adhesion. From these results, we suspect that compound 3 isolated from Bupleurum falcatum roots would be a good candidate for therapeutic strategies to treat inflammation.

  15. Essential oil of clove (Eugenia caryophyllata) augments the humoral immune response but decreases cell mediated immunity.

    Science.gov (United States)

    Halder, Sumita; Mehta, Ashish K; Mediratta, Pramod K; Sharma, Krishna K

    2011-08-01

    The present study was undertaken to explore the effect of the essential oil isolated from the buds of Eugenia caryophyllata on some immunological parameters. Humoral immunity was assessed by measuring the hemagglutination titre to sheep red blood cells and delayed type hypersensitivity was assessed by measuring foot pad thickness. Clove oil administration produced a significant increase in the primary as well as secondary humoral immune response. In addition, it also produced a significant decrease in foot pad thickness compared with the control group. Thus, these results suggest that clove oil can modulate the immune response by augmenting humoral immunity and decreasing cell mediated immunity. PMID:21796701

  16. Complement bound to tumor target cells enhances their sensitivity to macrophage-mediated killing

    Energy Technology Data Exchange (ETDEWEB)

    Bara, S.; Lint, T.F.

    1986-03-05

    Tumor cells are known to be susceptible to destruction by a variety of immune effector mechanisms including complement (C) and activated macrophages (M theta). The authors have chosen to study the interaction of these two effector systems by examining the effects of bound mouse C on the antibody-independent M theta-mediated lysis of the P815 mouse mastocytoma cell line. Hemolytically active normal mouse serum (NMS) was used to deposit C on tumor targets by an alternative pathway mechanism in the absence of added antibody. C3 was quantitated on the P815 cells by a cellular enzyme-linked immunosorbant assay. C. parvum-activated macrophages produced tumor cytolysis which was measured in a serum-free 16 hour /sup 51/Cr-release assay. Target cells which had been incubated with NMS for 30 min at 37/sup 0/C demonstrated a 30% increase in specific /sup 51/Cr-release at a 1:1 effector to target (E:T) ratio, as compared to targets incubated with heat-inactivated (56/sup 0/C, 30 min) NMS. The treatment of target cells with NMS alone did not cause lysis. At higher E:T ratios specific /sup 51/Cr-release approached a maximum level which was not increased further by C treatment of the target cells. However, at low E:T ratios, NMS increased the specific /sup 51/Cr-release in a dose-dependent fashion; this increase was abrogated by 10 mM EDTA. The kinetics of lysis of C-treated P815 cells by activated M theta does not differ from that of control P815 cells. These results indicate that target-bound C may enhance M theta-mediated killing of tumor cells.

  17. Tc17 cells mediate vaccine immunity against lethal fungal pneumonia in immune deficient hosts lacking CD4+ T cells.

    Directory of Open Access Journals (Sweden)

    Som Gowda Nanjappa

    Full Text Available Vaccines may help reduce the growing incidence of fungal infections in immune-suppressed patients. We have found that, even in the absence of CD4(+ T-cell help, vaccine-induced CD8(+ T cells persist and confer resistance against Blastomyces dermatitidis and Histoplasma capsulatum. Type 1 cytokines contribute to that resistance, but they also are dispensable. Although the role of T helper 17 cells in immunity to fungi is debated, IL-17 producing CD8(+ T cells (Tc17 cells have not been investigated. Here, we show that Tc17 cells are indispensable in antifungal vaccine immunity in hosts lacking CD4(+ T cells. Tc17 cells are induced upon vaccination, recruited to the lung on pulmonary infection, and act non-redundantly in mediating protection in a manner that requires neutrophils. Tc17 cells did not influence type I immunity, nor did the lack of IL-12 signaling augment Tc17 cells, indicating a distinct lineage and function. IL-6 was required for Tc17 differentiation and immunity, but IL-1R1 and Dectin-1 signaling was unexpectedly dispensable. Tc17 cells expressed surface CXCR3 and CCR6, but only the latter was essential in recruitment to the lung. Although IL-17 producing T cells are believed to be short-lived, effector Tc17 cells expressed low levels of KLRG1 and high levels of the transcription factor TCF-1, predicting their long-term survival and stem-cell like behavior. Our work has implications for designing vaccines against fungal infections in immune suppressed patients.

  18. Tc17 cells mediate vaccine immunity against lethal fungal pneumonia in immune deficient hosts lacking CD4+ T cells.

    Science.gov (United States)

    Nanjappa, Som Gowda; Heninger, Erika; Wüthrich, Marcel; Gasper, David Joseph; Klein, Bruce S

    2012-01-01

    Vaccines may help reduce the growing incidence of fungal infections in immune-suppressed patients. We have found that, even in the absence of CD4(+) T-cell help, vaccine-induced CD8(+) T cells persist and confer resistance against Blastomyces dermatitidis and Histoplasma capsulatum. Type 1 cytokines contribute to that resistance, but they also are dispensable. Although the role of T helper 17 cells in immunity to fungi is debated, IL-17 producing CD8(+) T cells (Tc17 cells) have not been investigated. Here, we show that Tc17 cells are indispensable in antifungal vaccine immunity in hosts lacking CD4(+) T cells. Tc17 cells are induced upon vaccination, recruited to the lung on pulmonary infection, and act non-redundantly in mediating protection in a manner that requires neutrophils. Tc17 cells did not influence type I immunity, nor did the lack of IL-12 signaling augment Tc17 cells, indicating a distinct lineage and function. IL-6 was required for Tc17 differentiation and immunity, but IL-1R1 and Dectin-1 signaling was unexpectedly dispensable. Tc17 cells expressed surface CXCR3 and CCR6, but only the latter was essential in recruitment to the lung. Although IL-17 producing T cells are believed to be short-lived, effector Tc17 cells expressed low levels of KLRG1 and high levels of the transcription factor TCF-1, predicting their long-term survival and stem-cell like behavior. Our work has implications for designing vaccines against fungal infections in immune suppressed patients.

  19. Characteristics of nobiletin-mediated alteration of gene expression in cultured cell lines

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    Nemoto, Kiyomitsu, E-mail: nemoto@u-shizuoka-ken.ac.jp [Department of Molecular Toxicology, School of Pharmaceutical Sciences, University of Shizuoka, 52-1 Yada, Suruga-ku, Shizuoka 422-8526 (Japan); Ikeda, Ayaka; Yoshida, Chiaki; Kimura, Junko; Mori, Junki [Department of Molecular Toxicology, School of Pharmaceutical Sciences, University of Shizuoka, 52-1 Yada, Suruga-ku, Shizuoka 422-8526 (Japan); Fujiwara, Hironori [Department of Anti-Dementia Functional Food Development, Research Center of Supercritical Fluid Technology, Graduate School of Engineering, Tohoku University, 6-6-7 Aoba, Aramaki, Aoba-ku, Sendai 980-8579 (Japan); Yokosuka, Akihito; Mimaki, Yoshihiro [Department of Medicinal Pharmacognosy, School of Pharmacy, Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji 192-0392 (Japan); Ohizumi, Yasushi [Department of Molecular Toxicology, School of Pharmaceutical Sciences, University of Shizuoka, 52-1 Yada, Suruga-ku, Shizuoka 422-8526 (Japan); Department of Anti-Dementia Functional Food Development, Research Center of Supercritical Fluid Technology, Graduate School of Engineering, Tohoku University, 6-6-7 Aoba, Aramaki, Aoba-ku, Sendai 980-8579 (Japan); Laboratory of Kampo Medicines, Yokohama College of Pharmacy, 601 Matano-cho, Totsuka-ku, Yokohama 245-0066 (Japan); Degawa, Masakuni [Department of Molecular Toxicology, School of Pharmaceutical Sciences, University of Shizuoka, 52-1 Yada, Suruga-ku, Shizuoka 422-8526 (Japan)

    2013-02-15

    Highlights: ► Nobiletin-mediated alterations of gene expression were examined with DNA microarrays. ► Three organ-derived cell lines were treated with 100 μM nobiletin for 24 h. ► In all cell lines, 3 endoplasmic reticulum stress-responsive genes were up-regulated. ► Some cell cycle-regulating and oxidative stress-promoting genes were down-regulated. ► These alterations may contribute to nobiletin-mediated biological effects. -- Abstract: Nobiletin, a polymethoxylated flavonoid that is highly contained in the peels of citrus fruits, exerts a wide variety of beneficial effects, including anti-proliferative effects in cancer cells, repressive effects in hyperlipidemia and hyperglycemia, and ameliorative effects in dementia at in vitro and in vivo levels. In the present study, to further understand the mechanisms of these actions of nobiletin, the nobiletin-mediated alterations of gene expression in three organ-derived cell lines – 3Y1 rat fibroblasts, HuH-7 human hepatocarcinoma cells, and SK-N-SH human neuroblastoma cells – were first examined with DNA microarrays. In all three cell lines, treatments with nobiletin (100 μM) for 24 h resulted in more than 200% increases in the expression levels of five genes, including the endoplasmic reticulum stress-responsive genes Ddit3, Trib3, and Asns, and in less than 50% decreases in the expression levels of seven genes, including the cell cycle-regulating genes Ccna2, Ccne2, and E2f8 and the oxidative stress-promoting gene Txnip. It was also confirmed that in each nobiletin-treated cell line, the levels of the DDIT3 (DNA-damage-inducible transcript 3, also known as CHOP and GADD153) and ASNS (asparagine synthetase) proteins were increased, while the level of the TXNIP (thioredoxin-interacting protein, also known as VDUP1 and TBP-2) protein was decreased. All these findings suggest that nobiletin exerts a wide variety of biological effects, at least partly, through induction of endoplasmic reticulum stress and

  20. Fluvastatin mediated breast cancer cell death: a proteomic approach to identify differentially regulated proteins in MDA-MB-231 cells.

    Directory of Open Access Journals (Sweden)

    Anantha Koteswararao Kanugula

    Full Text Available Statins are increasingly being recognized as anti-cancer agents against various cancers including breast cancer. To understand the molecular pathways targeted by fluvastatin and its differential sensitivity against metastatic breast cancer cells, we analyzed protein alterations in MDA-MB-231 cells treated with fluvastatin using 2-DE in combination with LC-MS/MS. Results revealed dys-regulation of 39 protein spots corresponding to 35 different proteins. To determine the relevance of altered protein profiles with breast cancer cell death, we mapped these proteins to major pathways involved in the regulation of cell-to-cell signaling and interaction, cell cycle, Rho GDI and proteasomal pathways using IPA analysis. Highly interconnected sub networks showed that vimentin and ERK1/2 proteins play a central role in controlling the expression of altered proteins. Fluvastatin treatment caused proteolysis of vimentin, a marker of epithelial to mesenchymal transition. This effect of fluvastatin was reversed in the presence of mevalonate, a downstream product of HMG-CoA and caspase-3 inhibitor. Interestingly, fluvastatin neither caused an appreciable cell death nor did modulate vimentin expression in normal mammary epithelial cells. In conclusion, fluvastatin alters levels of cytoskeletal proteins, primarily targeting vimentin through increased caspase-3- mediated proteolysis, thereby suggesting a role for vimentin in statin-induced breast cancer cell death.

  1. Cordyceps militaris Enhances Cell-Mediated Immunity in Healthy Korean Men.

    Science.gov (United States)

    Kang, Ho Joon; Baik, Hyun Wook; Kim, Sang Jung; Lee, Seong Gyu; Ahn, Hong Yup; Park, Ju Sang; Park, Sang Jong; Jang, Eun Jeong; Park, Sang Woon; Choi, Jin Young; Sung, Ji Hee; Lee, Seung Min

    2015-10-01

    Cordyceps militaris is a mushroom traditionally used for diverse pharmaceutical purposes in East Asia, including China, and has been found to be effective for enhancing immunity through various types of animal testing. The aim of this study is to determine the efficacy of C. militaris for enhancing cell-mediated immunity and its safety in healthy male adults. Healthy male adults were divided into the experimental group (n = 39), given 1.5 g/day of ethanol treated C. militaris in capsules, and the control group (n = 40), given the same number of identical placebo capsules filled with microcrystalline cellulose and lactose for 4 weeks from February 13 to March 14, 2012; the natural killer (NK) cell activity, lymphocyte proliferation index (PI), and T-helper cell 1 (Th1) cytokine cluster (interferon [IFN]-γ, interleukin [IL]-12, IL-2, and tumor necrosis factor [TNF]-α) were measured, along with stability test, at weeks 0, 2, and 4. The C. militaris group showed a statistically significant greater increase in NK200 (P = .0010), lymphocyte PI (P ≤ .0001), IL-2 (P = .0096), and IFN-γ (P = .0126), compared with the basal level, than the placebo group. There was no statistically significant adverse reaction. C. militaris enhanced the NK cell activity and lymphocyte proliferation and partially increased Th1 cytokine secretion. Therefore, C. militaris is safe and effective for enhancing cell-mediated immunity of healthy male adults. PMID:26284906

  2. Isoalantolactone Induces Reactive Oxygen Species Mediated Apoptosis in Pancreatic Carcinoma PANC-1 Cells

    Directory of Open Access Journals (Sweden)

    Muhammad Khan, Chuan Ding, Azhar Rasul, Fei Yi, Ting Li, Hongwen Gao, Rong Gao, Lili Zhong, Kun Zhang, Xuedong Fang, Tonghui Ma

    2012-01-01

    Full Text Available Isoalantolactone, a sesquiterpene lactone compound possesses antifungal, antibacteria, antihelminthic and antiproliferative activities. In the present study, we found that isoalantolactone inhibits growth and induces apoptosis in pancreatic cancer cells. Further mechanistic studies revealed that induction of apoptosis is associated with increased generation of reactive oxygen species, cardiolipin oxidation, reduced mitochondrial membrane potential, release of cytochrome c and cell cycle arrest at S phase. N-Acetyl Cysteine (NAC, a specific ROS inhibitor restored cell viability and completely blocked isoalantolactone-mediated apoptosis in PANC-1 cells indicating that ROS are involved in isoalantolactone-mediated apoptosis. Western blot study showed that isoalantolactone increased the expression of phosphorylated p38 MAPK, Bax, and cleaved caspase-3 and decreased the expression of Bcl-2 in a dose-dependent manner. No change in expression of phosphorylated p38 MAPK and Bax was found when cells were treated with isoalantolactone in the presence of NAC, indicating that activation of these proteins is directly dependent on ROS generation. The present study provides evidence for the first time that isoalantolactone induces ROS-dependent apoptosis through intrinsic pathway. Furthermore, our in vivo toxicity study demonstrated that isoalantolactone did not induce any acute or chronic toxicity in liver and kidneys of CD1 mice at dose of 100 mg/kg body weight. Therefore, isoalantolactone may be a safe chemotherapeutic candidate for the treatment of human pancreatic carcinoma.

  3. Transmembrane voltage potential of somatic cells controls oncogene-mediated tumorigenesis at long-range.

    Science.gov (United States)

    Chernet, Brook T; Levin, Michael

    2014-05-30

    The microenvironment is increasingly recognized as a crucial aspect of cancer. In contrast and complement to the field's focus on biochemical factors and extracellular matrix, we characterize a novel aspect of host:tumor interaction - endogenous bioelectric signals among non-excitable somatic cells. Extending prior work focused on the bioelectric state of cancer cells themselves, we show for the first time that the resting potentials of distant cells are critical for oncogene-dependent tumorigenesis. In the Xenopus laevis tadpole model, we used human oncogenes such as mutant KRAS to drive formation of tumor-like structures that exhibited overproliferation, increased nuclear size, hypoxia, acidity, and leukocyte attraction. Remarkably, misexpression of hyperpolarizing ion channels at distant sites within the tadpole significantly reduced the incidence of these tumors. The suppression of tumorigenesis could also be achieved by hyperpolarization using native CLIC1 chloride channels, suggesting a treatment modality not requiring gene therapy. Using a dominant negative approach, we implicate HDAC1 as the mechanism by which resting potential changes affect downstream cell behaviors. Based on published data on the voltage-mediated changes of butyrate flux through the SLC5A8 transporter, we present a model linking resting potentials of host cells to the ability of oncogenes to initiate tumorigenesis. Antibiotic data suggest that the relevant butyrate is generated by a native bacterial species, identifying a novel link between the microbiome and cancer that is mediated by alterations in bioelectric signaling. PMID:24830454

  4. HIF-mediated innate immune responses: cell signaling and therapeutic implications

    Directory of Open Access Journals (Sweden)

    Harris AJ

    2014-05-01

    Full Text Available Alison J Harris, AA Roger Thompson, Moira KB Whyte, Sarah R Walmsley Academic Unit of Respiratory Medicine, Department of Infection and Immunity, University of Sheffield, Sheffield, UK Abstract: Leukocytes recruited to infected, damaged, or inflamed tissues during an immune response must adapt to oxygen levels much lower than those in the circulation. Hypoxia inducible factors (HIFs are key mediators of cellular responses to hypoxia and, as in other cell types, HIFs are critical for the upregulation of glycolysis, which enables innate immune cells to produce adenosine triphosphate anaerobically. An increasing body of evidence demonstrates that hypoxia also regulates many other innate immunological functions, including cell migration, apoptosis, phagocytosis of pathogens, antigen presentation and production of cytokines, chemokines, and angiogenic and antimicrobial factors. Many of these functions are mediated by HIFs, which are not only stabilized posttranslationally by hypoxia, but also transcriptionally upregulated by inflammatory signals. Here, we review the role of HIFs in the responses of innate immune cells to hypoxia, both in vitro and in vivo, with a particular focus on myeloid cells, on which the majority of studies have so far been carried out. Keywords: hypoxia, neutrophils, monocytes, macrophages

  5. Comparative mechanisms of protein transduction mediated by cell-penetrating peptides in prokaryotes.

    Science.gov (United States)

    Liu, Betty Revon; Huang, Yue-Wern; Aronstam, Robert S; Lee, Han-Jung

    2015-04-01

    Bacterial and archaeal cell envelopes are complex multilayered barriers that serve to protect these microorganisms from their extremely harsh and often hostile environments. Import of exogenous proteins and nanoparticles into cells is important for biotechnological applications in prokaryotes. In this report, we demonstrate that cell-penetrating peptides (CPPs), both bacteria-expressed nona-arginine peptide (R9) and synthetic R9 (SR9), are able to deliver noncovalently associated proteins or quantum dots into four representative species of prokaryotes: cyanobacteria (Synechocystis sp. PCC 6803), bacteria (Escherichia coli DH5α and Arthrobacter ilicis D-50), and archaea (Thermus aquaticus). Although energy-dependent endocytosis is generally accepted as a hallmark that distinguishes eukaryotes from prokaryotes, cellular uptake of uncomplexed green fluorescent protein (GFP) by cyanobacteria was mediated by classical endocytosis. Mechanistic studies revealed that macropinocytosis plays a critical and major role in CPP-mediated protein transduction in all four prokaryotes. Membrane damage was not observed when cyanobacterial cells were treated with R9/GFP complexes, nor was cytotoxicity detected when bacteria or archaea were treated with SR9/QD complexes in the presence of macropinocytic inhibitors. These results indicate that the uptake of protein is not due to a compromise of membrane integrity in cyanobacteria, and that CPP can be an effective and safe carrier for membrane trafficking in prokaryotic cells. Our investigation provides important new insights into the transport of exogenous proteins and nanoparticles across the complex membrane systems of prokaryotes.

  6. PPARy phosphorylation mediated by JNK MAPK: a potential role in macrophage-derived foam cell formation

    Institute of Scientific and Technical Information of China (English)

    Ran YIN; Yu-gang DONG; Hong-lang LI

    2006-01-01

    Aim: To investigate whether oxidized low-density lipoprotein (ox-LDL) modulates peroxisome proliferator-activated receptor γ (PPARγ) activity through phosphorylation in macrophages, and the effect of PPARy phosphorylation on macrophages-derived foam cell formation. Methods: After exposing the cultured THP-1 cells to ox-LDL in the presence or absence of different mitogen-activated protein kinase (MAPK) inhibitors, PPARγ and phosphorylated PPARγ protein levels were detected by Western blot. MAPK activity was analyzed using MAP Kinase Assay Kit. Intracellular cholesterol accumulation was assessed by Oil red O staining and cholesterol oxidase enzymatic method. The Mrna level of PPARγ target gene was determined by reverse transcription-polymerase chain reaction (RT-PCR). Results: ox-LDL evaluated PPARγ phosphorylation status and subsequently decreased PPARγ target gene expression in a dose-dependent manner. Ox-LDL also induced MAPK activation. Treatment of THP-1 cells with c-Jun N-terminal kinase-, but not p38- or extracellular signal-regulated kinase-MAPK inhibitor, significantly suppressed PPARγ phosphorylation induced by ox-LDL, which in turn inhibited foam cell formation. Conclusion: In addition to its ligand-dependent activation, ox-LDL modulates PPARγ activity through phosphorylation, which is mediated by MAPK activation. PPARγ phosphorylation mediated by MAPK facilitates foam cell formation from macrophages exposed to ox-LDL.

  7. Effects of lipopolysaccharide on oligodendrocyte progenitor cells are mediated by astrocytes and microglia.

    Science.gov (United States)

    Pang, Y; Cai, Z; Rhodes, P G

    2000-11-15

    Oligodendrocytes are the primary cells injured in periventricular leukomalacia (PVL), a predominant form of brain white matter lesion in preterm infants. To explore the possible linkage between white matter injury and maternal infection, purified rat O-2A progenitor (Oligodendrocyte-type 2 astrocyte progenitor) cell cultures were used as a model in studying the effects of lipopolysaccharide (LPS), an endotoxin, on survival and differentiation of oligodendrocytes and the involvement of other glial cells in the effects of LPS. O-2A progenitor cells were cultured from optic nerves of 7-day-old rat pups in a chemically defined medium (CDM). Astrocyte and microglia cell cultures were prepared from the cortex of 1-day-old rat brains in the CDM. Direct treatment of LPS (1 microg/ml) to O-2A cells had no effect on viability or differentiation of these cells. When O-2A progenitor cells were cultured in the conditioned medium obtained from either astrocyte or microglial cell cultures for 48 hr, survival rate and differentiation of O-2A cells into mature oligodendrocytes were greatly enhanced as measured by the MTT assay and immunocytochemistry. The conditioned medium obtained from astrocytes or microglia treated with LPS for 48 hr, however, failed to show such a promotional effect on viability and differentiation of O-2A cells. When 5 microg/ml LPS was used to stimulate astrocytes or microglia, the conditioned medium from these glial cell cultures caused O-2A cell injury. The overall results indicate that astrocytes and microglia may promote viability and differentiation of O-2A progenitor cells under physiological conditions, but they may also mediate cytotoxic effects of LPS on oligodendrocytes under an infectious disease biochemical environment.

  8. Data correlations between gender, cytomegalovirus infection and T cells, NK cells, and soluble immune mediators in elderly humans.

    Science.gov (United States)

    Al-Attar, Ahmad; Presnell, Steven R; Peterson, Charlotte A; Thomas, D Travis; Lutz, Charles T

    2016-09-01

    We describe a cohort of 50 elderly subjects, age at least 70 years. We present gender-specific findings in T lymphocyte markers and soluble immune mediators. We show the correlation between cytomegalovirus infection status with CD56(dim) NK cell responses to a variety of stimuli and with CD56(bright)/CD56(dim) NK cell ratio. We also present the correlation of retinol binding protein (RBP)-4 plasma levels with NK cell responses and we explore the relationship between gender and adiponectin, 25(OH)D (vitamin D), and RBP4 in affecting CD56(dim) NK cell responses. These data are discussed in Al-Attar et al. (2016) [1]. PMID:27508213

  9. B7h-expressing dendritic cells and plasma B cells mediate distinct outcomes of ICOS costimulation in T cell-dependent antibody responses

    Directory of Open Access Journals (Sweden)

    Larimore Kevin

    2012-06-01

    Full Text Available Abstract Background The ICOS-B7h costimulatory receptor-ligand pair is required for germinal center formation, the production of isotype-switched antibodies, and antibody affinity maturation in response to T cell-dependent antigens. However, the potentially distinct roles of regulated B7h expression on B cells and dendritic cells in T cell-dependent antibody responses have not been defined. Results We generated transgenic mice with lineage-restricted B7h expression to assess the cell-type specific roles of B7h expression on B cells and dendritic cells in regulating T cell-dependent antibody responses. Our results show that endogenous B7h expression is reduced on B cells after activation in vitro and is also reduced in vivo on antibody-secreting plasma B cells in comparison to both naïve and germinal center B cells from which they are derived. Increasing the level of B7h expression on activated and plasma B cells in B-B7hTg mice led to an increase in the number of antibody-secreting plasma cells generated after immunization and a corresponding increase in the concentration of antigen-specific high affinity serum IgG antibodies of all isotypes, without affecting the number of responding germinal center B cells. In contrast, ICOS costimulation mediated by dendritic cells in DC-B7hTg mice contributed to germinal center formation and selectively increased IgG2a production without affecting the overall magnitude of antibody responses. Conclusions Using transgenic mice with lineage-restricted B7h expression, we have revealed distinct roles of ICOS costimulation mediated by dendritic cells and B cells in the regulation of T cell-dependent antibody responses.

  10. Distinct evolution of TLR-mediated dendritic cell cytokine secretion in patients with limited and diffuse cutaneous systemic sclerosis.

    NARCIS (Netherlands)

    Bon, L. van; Popa, C.; Huibens, R.J.F.; Vonk, M.C.; York, M.; Simms, R.; Hesselstrand, R.; Wuttge, D.M.; Lafyatis, R.; Radstake, T.R.D.J.

    2010-01-01

    BACKGROUND: Systemic sclerosis (SSc) is an autoimmune disease and accumulating evidence suggests a role for Toll-like receptor (TLR)-mediated activation of dendritic cells (DCs). OBJECTIVE: To map TLR-mediated cytokine responses of DCs from patients with SSc. METHODS: 45 patients with SSc were inclu

  11. Protein Kinases Possibly Mediate Hypergravity-Induced Changes in F-Actin Expression by Endothelial Cells

    Science.gov (United States)

    Love, Felisha D.; Melhado, Caroline D.; Bosah, Francis N.; Harris-Hooker, Sandra A.; Sanford, Gary L.

    1998-01-01

    Basic cellular functions such as electrolyte concentration, cell growth rate, glucose utilization, bone formation, response to growth stimulation, and exocytosis are modified in microgravity. These studies indicate that microgravity affects a number of physiological systems and included in this are cell signaling mechanisms. Rijken and coworkers performed growth factor studies that showed PKC signaling and actin microfilament organization appears to be sensitive to microgravity, suggesting that the inhibition of signal transduction by microgravity may be related to alterations in actin microfilament organization. However, similar studies have not been done for vascular cells. Vascular endothelial cells play critical roles in providing nutrients to organ and tissues and in wound repair. The major deterrent to ground-based microgravity studies is that it is impossible to achieved true microgravity for longer than a few minutes on earth. Hence, it has not been possible to conduct prolonged microgravity studies except for two models that simulate certain aspects of microgravity. However, hypergravity is quite easily achieved. Several researchers have shown that hypergravity will increase the proliferation of several different cell lines while decreasing cell motility and slowing liver regeneration following partial hepatectomy, These studies indicate the hypergravity also alters the behavior of most cells. Several investigators have shown that hypergravity affects the activation of several protein kinases (PKs) in cells. In this study, we investigated whether hypergravity alters the expression of f-actin by bovine aortic endothelial cells (BAECs) and the role of PK's (calmodulin 11 dependent, PKA and PKC) as mediators of these effects.

  12. Extracellular acidification stimulates GPR68 mediated IL-8 production in human pancreatic β cells.

    Science.gov (United States)

    Chandra, Vikash; Karamitri, Angeliki; Richards, Paul; Cormier, Françoise; Ramond, Cyrille; Jockers, Ralf; Armanet, Mathieu; Albagli-Curiel, Olivier; Scharfmann, Raphael

    2016-01-01

    Acute or chronic metabolic complications such as diabetic ketoacidosis are often associated with extracellular acidification and pancreatic β-cell dysfunction. However, the mechanisms by which human β-cells sense and respond to acidic pH remain elusive. In this study, using the recently developed human β-cell line EndoC-βH2, we demonstrate that β-cells respond to extracellular acidification through GPR68, which is the predominant proton sensing receptor of human β-cells. Using gain- and loss-of-function studies, we provide evidence that the β-cell enriched transcription factor RFX6 is a major regulator of GPR68. Further, we show that acidic pH stimulates the production and secretion of the chemokine IL-8 by β-cells through NF-кB activation. Blocking of GPR68 or NF-кB activity severely attenuated acidification induced IL-8 production. Thus, we provide mechanistic insights into GPR68 mediated β-cell response to acidic microenvironment, which could be a new target to protect β-cell against acidosis induced inflammation. PMID:27166427

  13. Adenovirus Mediated BIMS Transfer Induces Growth Supression and Apoptosis in Raji Lymphoma Cells

    Institute of Scientific and Technical Information of China (English)

    ZHAO Ya Ning; LI Qiang

    2014-01-01

    Objective To transfer pro-apoptotic BIM directly into tumor cells bypass the complicated biological processes of BIM activation so as to reverse the chemoresistance of cancer cells. Methods BIMS was specifically amplified from HL-60 cells by RT-PCR, confirmed to be correct by sequencing and cloned into shuttle vector pAdTrack-CMV carrying a green fluorescence protein gene to generate a recombinant plasmid pAdTrack-CMV-BIMS. This plasmid and adenovirus backbone plasmid pAdEasy-1 were linearized and electroporated into E.coli BJ5183 host bacteria to mediate homologous recombination. The positive clone was identified by restrict endonuclease digestion. The recombinant pAdEasy-CMV-BIMS was transferred into HEK293 cells for packaging and amplification. The successful construction of recombinant human BIMS adenovirus (Ad-BIMS) was demonstrated by Western blot. To test whether Ad-BIMS has the capability of inducing apoptosis of tumor cells, Ad-BIMS was used to infect GC resistant Burkitt lymphoma Raji cells. Results After infected for 2-5 days, BIMS expression in Raji cells was detected by RT-PCR and Western blot. The significant growth retardation and apoptosis of Raji cells were also observed by MTT and flow cytometry. Conclusion These results indicated that BIMS might be a potential candidate of gene therapy for chemoresistant tumor cells.

  14. Exogenous DNA internalisation by sperm cells is improved by combining lipofection and restriction enzyme mediated integration.

    Science.gov (United States)

    Churchil, R R; Gupta, J; Singh, A; Sharma, D

    2011-06-01

    1. Three types of exogenous DNA inserts, i.e. complete linearised pVIVO2-GFP/LacZ vector (9620 bp), the LacZ gene (5317 bp) and the GFP gene (2152 bp) were used to transfect chicken spermatozoa through simple incubation of sperm cells with insert. 2. PCR assay, Dot Blot hybridisation and Southern hybridisation showed the successful internalisation of exogenous DNA by chicken sperm cells. 3. Lipofection and Restriction Enzyme Mediated Integration (REMI) were used to improve the rate of internalisation of exogenous DNA by sperm cells. 4. Results from dot blot as well as Southern hybridisation were semi-quantified and improved exogenous DNA uptake by sperm cells through lipofection and REMI. Stronger signals were observed from hybridisation of LacZ as well as GFP specific probe with the DNA from lipofected exogenous DNA transfected sperm DNA in comparison with those transfected with nude exogenous DNA.

  15. Transferrin protein nanospheres: a nanoplatform for receptor-mediated cancer cell labeling and gene delivery

    Science.gov (United States)

    McDonald, Michael A.; Spurlin, Tighe A.; Tona, Alessandro; Elliott, John T.; Halter, Michael; Plant, Anne L.

    2010-02-01

    This paper presents preliminary results on the use of transferrin protein nanospheres (TfpNS) for targeting cancer cells in vitro. Protein nanospheres represent an easily prepared and modifiable nanoplatform for receptor-specific targeting, molecular imaging and gene delivery. Rhodamine B isothiocyanate conjugated TfpNS (RBITC-TfpNS) show significantly enhanced uptake in vitro in SK-MEL-28 human malignant melanoma cells known to overexpress transferrin receptors compared to controls. RBITCTfpNS labeling of the cancer cells is due to transferrin receptor-mediated uptake, as demonstrated by competitive inhibition with native transferrin. Initial fluorescence microscopy studies indicate GFP plasmid can be transfected into melanoma cells via GFP plasmid encapsulated by TfpNS.

  16. Trafficking of α1B-adrenergic receptor mediated by inverse agonist in living cells

    Institute of Scientific and Technical Information of China (English)

    MingXU; Ying-huaGUAN; NingXU; Zhang-yiLIANG; Shu-yiWang; YaoSONG; Chi-deHAN; Xin-shengZHAO; You-yiZHANG

    2005-01-01

    AIM The project is aimed at understanding the action of inverse agonist at single molecule level and capturing the real time picture of molecular behavior of α1B-adrenergic receptor (AR) mediated by inverse agonist in living cells by single molecule detection (SMD). METHODS The location and distribution of α1B-AR was detected by laser confocal and whole cell 3H-prazosin binding assay. Dynamic imaging of BODIPY-FL-labeled prazosin (Praz), specific antagonist of (1-AR, was observed in α1B-AR stably expressed human embryonic kidney 293 (HEK293) living cells. The detection of real-time dynamic behaviors of AR was achieved by using fluorescence-labeled AR and its ligand combined with SMD techniques. RESULTS α1B-AR was predominantly distributed on the cell surface and 8.2% of the total receptors were located in cytosol.

  17. Enhanced killing of chordoma cells by antibody-dependent cell-mediated cytotoxicity employing the novel anti-PD-L1 antibody avelumab.

    Science.gov (United States)

    Fujii, Rika; Friedman, Eitan R; Richards, Jacob; Tsang, Kwong Y; Heery, Christopher R; Schlom, Jeffrey; Hodge, James W

    2016-06-01

    Chordoma, a rare bone tumor derived from the notochord, has been shown to be resistant to conventional therapies. Checkpoint inhibition has shown great promise in immune-mediated therapy of diverse cancers. The anti-PD-L1 mAb avelumab is unique among checkpoint inhibitors in that it is a fully human IgG1 capable of mediating antibody-dependent cell-mediated cytotoxicity (ADCC) of PD-L1-expressing tumor cells. Here, we investigated avelumab as a potential therapy for chordoma. We examined 4 chordoma cell lines, first for expression of PD-L1, and in vitro for ADCC killing using NK cells and avelumab. PD-L1 expression was markedly upregulated by IFN-γ in all 4 chordoma cell lines, which significantly increased sensitivity to ADCC. Brachyury is a transcription factor that is uniformly expressed in chordoma. Clinical trials are ongoing in which chordoma patients are treated with brachyury-specific vaccines. Co-incubating chordoma cells with brachyury-specific CD8+ T cells resulted in significant upregulation of PD-L1 on the tumor cells, mediated by the CD8+ T cells' IFN-γ production, and increased sensitivity of chordoma cells to avelumab-mediated ADCC. Residential cancer stem cell subpopulations of chordoma cells were also killed by avelumab-mediated ADCC to the same degree as non-cancer stem cell populations. These findings suggest that as a monotherapy for chordoma, avelumab may enable endogenous NK cells, while in combination with T-cell immunotherapy, such as a vaccine, avelumab may enhance NK-cell killing of chordoma cells via ADCC.

  18. Trichomonas vaginalis and Tritrichomonas foetus: interaction with fibroblasts and muscle cells - new insights into parasite-mediated host cell cytotoxicity

    Directory of Open Access Journals (Sweden)

    Ricardo Chaves Vilela

    2012-09-01

    Full Text Available Trichomonas vaginalis and Tritrichomonas foetus are parasitic, flagellated protists that inhabit the urogenital tract of humans and bovines, respectively. T. vaginalis causes the most prevalent non-viral sexually transmitted disease worldwide and has been associated with an increased risk for human immunodeficiency virus-1 infection in humans. Infections by T. foetus cause significant losses to the beef industry worldwide due to infertility and spontaneous abortion in cows. Several studies have shown a close association between trichomonads and the epithelium of the urogenital tract. However, little is known concerning the interaction of trichomonads with cells from deeper tissues, such as fibroblasts and muscle cells. Published parasite-host cell interaction studies have reported contradictory results regarding the ability of T. foetus and T. vaginalis to interact with and damage cells of different tissues. In this study, parasite-host cell interactions were examined by culturing primary human fibroblasts obtained from abdominal biopsies performed during plastic surgeries with trichomonads. In addition, mouse 3T3 fibroblasts, primary chick embryo myogenic cells and L6 muscle cells were also used as models of target cells. The parasite-host cell cultures were processed for scanning and transmission electron microscopy and were tested for cell viability and cell death. JC-1 staining, which measures mitochondrial membrane potential, was used to determine whether the parasites induced target cell damage. Terminal deoxynucleotidyltransferase-mediated dUTP nick end labelling staining was used as an indicator of chromatin damage. The colorimetric crystal violet assay was performed to ana-lyse the cytotoxicity induced by the parasite. The results showed that T. foetus and T. vaginalis adhered to and were cytotoxic to both fibroblasts and muscle cells, indicating that trichomonas infection of the connective and muscle tissues is likely to occur; such

  19. The adhesion receptor CD44 promotes atherosclerosis by mediating inflammatory cell recruitment and vascular cell activation

    OpenAIRE

    Cuff, Carolyn A.; Kothapalli, Devashish; Azonobi, Ijeoma; Chun, Sam; Zhang, Yuanming; Belkin, Richard; Yeh, Christine; Secreto, Anthony; Richard K Assoian; Rader, Daniel J; Puré, Ellen

    2001-01-01

    Atherosclerosis causes most acute coronary syndromes and strokes. The pathogenesis of atherosclerosis includes recruitment of inflammatory cells to the vessel wall and activation of vascular cells. CD44 is an adhesion protein expressed on inflammatory and vascular cells. CD44 supports the adhesion of activated lymphocytes to endothelium and smooth muscle cells. Furthermore, ligation of CD44 induces activation of both inflammatory and vascular cells. To assess the potential contribution of CD4...

  20. Endogenous n-3 Polyunsaturated Fatty Acids Attenuate T Cell-Mediated Hepatitis via Autophagy Activation

    Science.gov (United States)

    Li, Yanli; Tang, Yuan; Wang, Shoujie; Zhou, Jing; Zhou, Jia; Lu, Xiao; Bai, Xiaochun; Wang, Xiang-Yang; Chen, Zhengliang; Zuo, Daming

    2016-01-01

    Omega-3 polyunsaturated fatty acids (n-3 PUFAs) exert anti-inflammatory effects in several liver disorders, including cirrhosis, acute liver failure, and fatty liver disease. To date, little is known about their role in immune-mediated liver diseases. In this study, we used fat-1 transgenic mice rich in endogenous n-3 PUFAs to examine the role of n-3 PUFAs in immune-mediated liver injury. Concanavalin A (Con A) was administered intravenously to wild-type (WT) and fat-1 transgenic mice to induce T cell-mediated hepatitis. Reduced liver damage was shown in Con A-administrated fat-1 transgenic mice, as evidenced by decreased mortality, attenuated hepatic necrosis, lessened serum alanine aminotransferase activity, and inhibited production of pro-inflammatory cytokines (e.g., TNF-α, IL-6, IL-17A, and IFN-γ). In vivo and in vitro studies demonstrated that n-3 PUFAs significantly inhibited the activation of hepatic T cells and the differentiation of Th1 cells after Con A challenge. Further studies showed that n-3 PUFAs markedly increased autophagy level in Con A-treated fat-1 T cells compared with the WT counterparts. Blocking hepatic autophagy activity with chloroquine diminished the differences in T cell activation and liver injury between Con A-injected WT and fat-1 transgenic mice. We conclude that n-3 PUFAs limit Con A-induced hepatitis via an autophagy-dependent mechanism and could be exploited as a new therapeutic approach for autoimmune hepatitis. PMID:27679638

  1. Sildenafil (Viagra) sensitizes prostate cancer cells to doxorubicin-mediated apoptosis through CD95.

    Science.gov (United States)

    Das, Anindita; Durrant, David; Mitchell, Clint; Dent, Paul; Batra, Surinder K; Kukreja, Rakesh C

    2016-01-26

    We previously reported that Sildenafil enhances apoptosis and antitumor efficacy of doxorubicin (DOX) while attenuating its cardiotoxic effect in prostate cancer. In the present study, we investigated the mechanism by which sildenafil sensitizes DOX in killing of prostate cancer (PCa) cells, DU145. The death receptor Fas (APO-1 or CD95) induces apoptosis in many carcinoma cells, which is negatively regulated by anti-apoptotic molecules such as FLIP (Fas-associated death domain (FADD) interleukin-1-converting enzyme (FLICE)-like inhibitory protein). Co-treatment of PCa cells with sildenafil and DOX for 48 hours showed reduced expression of both long and short forms of FLIP (FLIP-L and -S) as compared to individual drug treatment. Over-expression of FLIP-s with an adenoviral vector attentuated the enhanced cell-killing effect of DOX and sildenafil. Colony formation assays also confirmed that FLIP-S over-expression inhibited the DOX and sildenafil-induced synergistic killing effect as compared to the cells infected with an empty vector. Moreover, siRNA knock-down of CD95 abolished the effect of sildenafil in enhancing DOX lethality in cells, but had no effect on cell killing after treatment with a single agent. Sildenafil co-treatment with DOX inhibited DOX-induced NF-κB activity by reducing phosphorylation of IκB and nuclear translocation of the p65 subunit, in addition to down regulation of FAP-1 (Fas associated phosphatase-1, a known inhibitor of CD95-mediated apoptosis) expression. This data provides evidence that the CD95 is a key regulator of sildenafil and DOX mediated enhanced cell death in prostate cancer. PMID:26716643

  2. Nuclear DAMP complex-mediated RAGE-dependent macrophage cell death

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Ruochan [Department of Surgery, University of Pittsburgh, Pittsburgh, PA 15213 (United States); Department of Infectious Diseases and State Key Lab of Viral Hepatitis, Xiangya Hospital, Central South University, Changsha, Hunan 410008 (China); Fu, Sha; Fan, Xue-Gong [Department of Infectious Diseases and State Key Lab of Viral Hepatitis, Xiangya Hospital, Central South University, Changsha, Hunan 410008 (China); Lotze, Michael T.; Zeh, Herbert J. [Department of Surgery, University of Pittsburgh, Pittsburgh, PA 15213 (United States); Tang, Daolin, E-mail: tangd2@upmc.edu [Department of Surgery, University of Pittsburgh, Pittsburgh, PA 15213 (United States); Kang, Rui, E-mail: kangr@upmc.edu [Department of Surgery, University of Pittsburgh, Pittsburgh, PA 15213 (United States)

    2015-03-13

    High mobility group box 1 (HMGB1), histone, and DNA are essential nuclear components involved in the regulation of chromosome structure and function. In addition to their nuclear function, these molecules act as damage-associated molecular patterns (DAMPs) alone or together when released extracellularly. The synergistic effect of these nuclear DNA-HMGB1-histone complexes as DAMP complexes (nDCs) on immune cells remains largely unexplored. Here, we demonstrate that nDCs limit survival of macrophages (e.g., RAW264.7 and peritoneal macrophages) but not cancer cells (e.g., HCT116, HepG2 and Hepa1-6). nDCs promote production of inflammatory tumor necrosis factor α (TNFα) release, triggering reactive oxygen species-dependent apoptosis and necrosis. Moreover, the receptor for advanced glycation end products (RAGE), but not toll-like receptor (TLR)-4 and TLR-2, was required for Akt-dependent TNFα release and subsequent cell death following treatment with nDCs. Genetic depletion of RAGE by RNAi, antioxidant N-Acetyl-L-cysteine, and TNFα neutralizing antibody significantly attenuated nDC-induced cell death. These findings provide evidence supporting novel signaling mechanisms linking nDCs and inflammation in macrophage cell death. - Highlights: • Nuclear DAMP complexes (nDCs) selectively induce cell death in macrophages, but not cancer cells. • TNFα-mediated oxidative stress is required for nDC-induced death. • RAGE-mediated Akt activation is required for nDC-induced TNFα release. • Blocking RAGE and TNFα inhibits nDC-induced macrophage cell death.

  3. TFF3 mediated induction of VEGF via hypoxia in human gastric cancer SGC-7901 cells.