311 research outputs found

    Society for immunotherapy of cancer (SITC) statement on the proposed changes to the common rule

    Get PDF
    The Common Rule is a set of ethical principles that provide guidance on the management of human subjects taking part in biomedical and behavioral research in the United States. The elements of the Common Rule were initially developed in 1981 following a revision of the Declaration of Helsinki in 1975. Most academic facilities follow the Common Rule in the regulation of clinical trials research. Recently, the government has suggested a revision of the Common Rule to include more contemporary and streamlined oversight of clinical research. In this commentary, the leadership of the Society for Immunotherapy of Cancer (SITC) provides their opinion on this plan. While the Society recognizes the considerable contribution of clinical research in supporting progress in tumor immunotherapy and supports the need for revisions to the Common Rule, there is also some concern over certain elements which may restrict access to biospecimens and clinical data at a time when high throughput technologies, computational biology and assay standardization is allowing major advances in understanding cancer biology and providing potential predictive biomarkers of immunotherapy response. The Society values its professional commitment to patients for improving clinical outcomes with tumor immunotherapy and supports continued discussion with all stakeholders before implementing changes to the Common Rule in order to ensure maximal patient protections while promoting continued clinical research at this historic time in cancer research

    Identification of novel subgroup a variants with enhanced receptor binding and replicative capacity in primary isolates of anaemogenic strains of feline leukaemia virus

    Get PDF
    <b>BACKGROUND:</b> The development of anaemia in feline leukaemia virus (FeLV)-infected cats is associated with the emergence of a novel viral subgroup, FeLV-C. FeLV-C arises from the subgroup that is transmitted, FeLV-A, through alterations in the amino acid sequence of the receptor binding domain (RBD) of the envelope glycoprotein that result in a shift in the receptor usage and the cell tropism of the virus. The factors that influence the transition from subgroup A to subgroup C remain unclear, one possibility is that a selective pressure in the host drives the acquisition of mutations in the RBD, creating A/C intermediates with enhanced abilities to interact with the FeLV-C receptor, FLVCR. In order to understand further the emergence of FeLV-C in the infected cat, we examined primary isolates of FeLV-C for evidence of FeLV-A variants that bore mutations consistent with a gradual evolution from FeLV-A to FeLV-C.<p></p> <b>RESULTS:</b> Within each isolate of FeLV-C, we identified variants that were ostensibly subgroup A by nucleic acid sequence comparisons, but which bore mutations in the RBD. One such mutation, N91D, was present in multiple isolates and when engineered into a molecular clone of the prototypic FeLV-A (Glasgow-1), enhanced replication was noted in feline cells. Expression of the N91D Env on murine leukaemia virus (MLV) pseudotypes enhanced viral entry mediated by the FeLV-A receptor THTR1 while soluble FeLV-A Env bearing the N91D mutation bound more efficiently to mouse or guinea pig cells bearing the FeLV-A and -C receptors. Long-term in vitro culture of variants bearing the N91D substitution in the presence of anti-FeLV gp70 antibodies did not result in the emergence of FeLV-C variants, suggesting that additional selective pressures in the infected cat may drive the subsequent evolution from subgroup A to subgroup C.<p></p> <b>CONCLUSIONS:</b> Our data support a model in which variants of FeLV-A, bearing subtle differences in the RBD of Env, may be predisposed towards enhanced replication in vivo and subsequent conversion to FeLV-C. The selection pressures in vivo that drive the emergence of FeLV-C in a proportion of infected cats remain to be established

    Genetic determinants of co-accessible chromatin regions in activated T cells across humans.

    Get PDF
    Over 90% of genetic variants associated with complex human traits map to non-coding regions, but little is understood about how they modulate gene regulation in health and disease. One possible mechanism is that genetic variants affect the activity of one or more cis-regulatory elements leading to gene expression variation in specific cell types. To identify such cases, we analyzed ATAC-seq and RNA-seq profiles from stimulated primary CD4+ T cells in up to 105 healthy donors. We found that regions of accessible chromatin (ATAC-peaks) are co-accessible at kilobase and megabase resolution, consistent with the three-dimensional chromatin organization measured by in situ Hi-C in T cells. Fifteen percent of genetic variants located within ATAC-peaks affected the accessibility of the corresponding peak (local-ATAC-QTLs). Local-ATAC-QTLs have the largest effects on co-accessible peaks, are associated with gene expression and are enriched for autoimmune disease variants. Our results provide insights into how natural genetic variants modulate cis-regulatory elements, in isolation or in concert, to influence gene expression

    Alternative statistical methods for estimating efficacy of interferon beta-1b for multiple sclerosis clinical trials

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>In the randomized study of interferon beta-1b (IFN beta-1b) for multiple sclerosis (MS), it has usually been evaluated the simple annual relapse rate as the study endpoint. This study aimed to investigate the performance of various regression models using information regarding the time to each recurrent event and considering the MS specific data generation process, and to estimate the treatment effect of a MS clinical trial data.</p> <p>Methods</p> <p>We conducted a simulation study with consideration of the pathological characteristics of MS, and applied alternative efficacy estimation methods to real clinical trial data, including 5 extended Cox regression models for time-to-event analysis, a Poisson regression model and a Poisson regression model with Generalized Estimating Equations (GEE). We adjusted for other important covariates that may have affected the outcome.</p> <p>Results</p> <p>We compared the simulation results for each model. The hazard ratios of real data were estimated for each model including the effects of other covariates. The results (hazard ratios of high-dose to low-dose) of all models were approximately 0.7 (range, 0.613 - 0.769), whereas the annual relapse rate ratio was 0.714.</p> <p>Conclusions</p> <p>The precision of the treatment estimation was increased by application of the alternative models. This suggests that the use of alternative models that include recurrence event data may provide better analyses.</p

    Tear fluid biomarkers in ocular and systemic disease: potential use for predictive, preventive and personalised medicine

    Get PDF
    In the field of predictive, preventive and personalised medicine, researchers are keen to identify novel and reliable ways to predict and diagnose disease, as well as to monitor patient response to therapeutic agents. In the last decade alone, the sensitivity of profiling technologies has undergone huge improvements in detection sensitivity, thus allowing quantification of minute samples, for example body fluids that were previously difficult to assay. As a consequence, there has been a huge increase in tear fluid investigation, predominantly in the field of ocular surface disease. As tears are a more accessible and less complex body fluid (than serum or plasma) and sampling is much less invasive, research is starting to focus on how disease processes affect the proteomic, lipidomic and metabolomic composition of the tear film. By determining compositional changes to tear profiles, crucial pathways in disease progression may be identified, allowing for more predictive and personalised therapy of the individual. This article will provide an overview of the various putative tear fluid biomarkers that have been identified to date, ranging from ocular surface disease and retinopathies to cancer and multiple sclerosis. Putative tear fluid biomarkers of ocular disorders, as well as the more recent field of systemic disease biomarkers, will be shown

    Reduced type I interferon production by dendritic cells and weakened antiviral immunity in patients with Wiskott-Aldrich syndrome protein deficiency

    Get PDF
    Background: Wiskott-Aldrich syndrome (WAS) is a rare X-linked primary immunodeficiency caused by absence of Wiskott-Aldrich syndrome protein (WASP) expression, resulting in defective function of many immune cell lineages and susceptibility to severe bacterial, viral, and fungal infections. Despite a significant proportion of patients with WAS having recurrent viral infections, surprisingly little is known about the effects of WASP deficiency on antiviral immunity. Objective: We sought to evaluate the antiviral immune response in patients with WASP deficiency in vivo. Methods: Viral clearance and associated immunopathology were measured after infection of WASP-deficient (WAS KO) mice with lymphocytic choriomeningitis virus (LCMV). Induction of antiviral CD8 T-cell immunity and cytotoxicity was documented in WAS KO mice by means of temporal enumeration of total and antigen-specific T-cell numbers. Type I interferon (IFN-I) production was measured in serum in response to LCMV challenge and characterized in vivo by using IFN-I reporter mice crossed with WAS KO mice. Results: WAS KO mice showed reduced viral clearance and enhanced immunopathology during LCMV infection. This was attributed to both an intrinsic CD8 T-cell defect and defective priming of CD8 T cells by dendritic cells (DCs). IFN-I production by WAS KO DCs was reduced both in vivo and in vitro. Conclusions: These studies use a well-characterized model of persistence-prone viral infection to reveal a critical deficiency of CD8 T-cell responses in murine WASP deficiency, in which abrogated production of IFN-I by DCs might play an important contributory role. These findings might help us to understand the immunodeficiency of WAS. © 2012 American Academy of Allergy, Asthma & Immunology

    Zinc uptake promotes myoblast differentiation via Zip7 transporter and activation of Akt signalling transduction pathway

    Get PDF
    [EN] Myogenic regeneration occurs through a chain of events beginning with the output of satellite cells from quiescent state, formation of competent myoblasts and later fusion and differentiation into myofibres. Traditionally, growth factors are used to stimulate muscle regeneration but this involves serious off-target effects, including alterations in cell homeostasis and cancer. In this work, we have studied the use of zinc to trigger myogenic differentiation. We show that zinc promotes myoblast proliferation, differentiation and maturation of myofibres. We demonstrate that this process occurs through the PI3K/Akt pathway, via zinc stimulation of transporter Zip7. Depletion of zinc transporter Zip7 by RNA interference shows reduction of both PI3K/Akt signalling and a significant reduction of multinucleated myofibres and myotubes development. Moreover, we show that mature myofibres, obtained through stimulation with high concentrations of zinc, accumulate zinc and so we hypothesise their function as zinc reservoirs into the cell.P.R. and R.S. acknowledges support from the Spanish Ministry of Economy and Competitiveness (MINECO) (MAT2015-69315-C3-1-R). P.R. acknowledges the Fondo Europeo de Desarrollo Regional (FEDER). CIBER-BBN is an initiative funded by the VI National R&D&I Plan 2008-2011, Iniciativa Ingenio 2010, Consolider Program, CIBER Actions and financed by the Instituto de Salud Carlos III with assistance from the European Regional Development Fund. R.S. acknowledges the support from the Spanish MECD through the PRX16/00208 grant. MSS acknowledges support from the European Research Council (ERC - HealInSynergy 306990) and the UK Engineering and Physical Sciences Research Council (EPSRC - EP/P001114/1)Mnatsakanyan, H.; Sabater I Serra, R.; Rico Tortosa, PM.; Salmerón Sánchez, M. (2018). Zinc uptake promotes myoblast differentiation via Zip7 transporter and activation of Akt signalling transduction pathway. Scientific Reports. 8:1-14. https://doi.org/10.1038/s41598-018-32067-0S1148Frontera, W. R. & Ochala, J. Skeletal muscle: a brief review of structure and function. Calcif. Tissue Int. 96, 183–195 (2015).Wolfe, R. R., Frontera, W. R. & Ochala, J. The underappreciated role of muscle in health and disease. Am. J. Clin. Nutr. 84, 475–82 (2006).Sciorati, C., Rigamonti, E., Manfredi, A. A. & Rovere-Querini, P. Cell death, clearance and immunity in the skeletal muscle. Cell Death Differ. 23, 927–937 (2016).Wang, Y. X. & Rudnicki, M. A. Satellite cells, the engines of muscle repair. Nat. Rev. Mol. Cell Biol. 13, 127–133 (2011).Yin, H., Price, F. & Rudnicki, M. A. Satellite cells and the muscle stem cell niche. Physiol. Rev. 93, 23–67 (2013).Dhawan, J. & Rando, T. A. Stem cells in postnatal myogenesis: Molecular mechanisms of satellite cell quiescence, activation and replenishment. Trends Cell Biol. 15, 666–673 (2005).Yun, K. & Wold, B. Skeletal muscle determination and differentiation: Story of a core regulatory network and its context. Curr. Opin. Cell Biol. 8, 877–889 (1996).Gharaibeh, B. et al. Biological approaches to improve skeletal muscle healing after injury and disease. Birth Defects Res. Part C Embryo Today Rev. 96, 82–94 (2012).Schiaffino, S. & Mammucari, C. Regulation of skeletal muscle growth by the IGF1-Akt/PKB pathway: insights from genetic models. Skelet. Muscle 1, 4 (2011).Sandri, M. Signaling in muscle atrophy and hypertrophy. Physiology (Bethesda). 23, 160–70 (2008).Karalaki, M., Fili, S., Philippou, A. & Koutsilieris, M. Muscle regeneration: cellular and molecular events. In Vivo 23, 779–96 (2009).Fujio, Y. et al. Cell cycle withdrawal promotes myogenic induction of Akt, a positive modulator of myocyte survival. Mol. Cell. Biol. 19, 5073–82 (1999).Wilson, E. M. & Rotwein, P. Control of MyoD function during initiation of muscle differentiation by an autocrine signaling pathway activated by insulin-like growth factor-II. J. Biol. Chem. 281, 29962–29971 (2006).Sun, L., Liu, L., Yang, X. & Wu, Z. Akt binds prohibitin 2 and relieves its repression of MyoD and muscle differentiation. J. Cell Sci. 117, 3021–3029 (2004).Milner, D. & Cameron, J. Muscle repair and regeneration: stem cells, scaffolds, and the contributions of skeletal muscle to amphibian limb regeneration. Curr. Top. Microbiol. Immunol. 367, 133–159 (2013).Liu, C. et al. PI3K/Akt signaling transduction pathway is involved in rat vascular smooth muscle cell proliferation induced by apelin-13. Acta Biochim Biophys Sin 42, 396–402 (2010).Eriksson, M., Taskinen, M. & Leppä, S. Mitogen Activated Protein Kinase-Dependent Activation of c-Jun and c-Fos is required for Neuronal differentiation but not for Growth and Stress Reposne in PC12 cells. J. Cell. Physiol. 207, 12–22 (2006).Arsic, N. et al. Vascular endothelial growth factor stimulates skeletal muscle regeneration in Vivo. Mol. Ther. 10, 844–854 (2004).Borselli, C. et al. Functional muscle regeneration with combined delivery of angiogenesis and myogenesis factors. Proc. Natl. Acad. Sci. USA 107, 3287–3292 (2010).Hanft, J. R. et al. Phase I trial on the safety of topical rhVEGF on chronic neuropathic diabetic foot ulcers. J. Wound Care 17(30–2), 34–7 (2008).Simón-Yarza, T. et al. Vascular endothelial growth factor-delivery systems for cardiac repair: An overview. Theranostics 2, 541–552 (2012).Briquez, P. S., Hubbell, J. A. & Martino, M. M. Extracellular Matrix-Inspired Growth Factor Delivery Systems for Skin Wound Healing. Adv. Wound Care 4, 479–489 (2015).Barthel, A., Ostrakhovitch, E. A., Walter, P. L., Kampkötter, A. & Klotz, L. O. Stimulation of phosphoinositide 3-kinase/Akt signaling by copper and zinc ions: Mechanisms and consequences. Arch. Biochem. Biophys. 463, 175–182 (2007).Ostrakhovitch, E. A., Lordnejad, M. R., Schliess, F., Sies, H. & Klotz, L.-O. Copper ions strongly activate the phosphoinositide-3-kinase/Akt pathway independent of the generation of reactive oxygen species. Arch. Biochem. Biophys. 397, 232–239 (2002).Kaur, K., Gupta, R., Saraf, S. A. & Saraf, S. K. Zinc: The metal of life. Compr. Rev. Food Sci. Food Saf. 13, 358–376 (2014).Coleman, J. E. Zinc proteins: enzymes, storage proteins, transcription factors, and replication proteins. Annu. Rev. Biochem. 61, 897–946 (1992).Fukada, T. & Kambe, T. Molecular and genetic features of zinc transporters in physiology and pathogenesis. Metallomics 3, 662–674 (2011).Murakami, M. & Hirano, T. Intracellular zinc homeostasis and zinc signaling. Cancer Sci. 99, 1515–1522 (2008).Hogstrand, C., Kille, P., Nicholson, R. I. & Taylor, K. M. Zinc transporters and cancer: a potential role for ZIP7 as a hub for tyrosine kinase activation. Trends Mol. Med. 15, 101–111 (2009).Kolenko, V., Teper, E., Kutikov, A. & Uzzo, R. Zinc and zinc transporters in prostate carcinogenesis. Nat. Rev. Urol. 10, 219–26 (2013).Myers, S. A., Nield, A., Chew, G. S. & Myers, M. A. The zinc transporter, Slc39a7 (Zip7) is implicated in glycaemic control in skeletal muscle cells. Plos One 8 (2013).Kambe, T., Tsuji, T., Hashimoto, A. & Itsumura, N. The Physiological, Biochemical, and Molecular Roles of Zinc Transporters in Zinc Homeostasis and Metabolism. Physiol. Rev. 95, 749–784 (2015).Jinno, N., Nagata, M. & Takahashi, T. Marginal zinc deficiency negatively affects recovery from muscle injury in mice. Biol. Trace Elem. Res. 158, 65–72 (2014).Taylor, K. M., Hiscox, S., Nicholson, R. I., Hogstrand, C. & Kille, P. Protein Kinase CK2 Triggers Cytosolic Zinc Signaling Pathways by Phosphorylation of Zinc Channel ZIP7. Sci. Signal. 5, ra11–ra11 (2012).Yamasaki, S. et al. Zinc is a novel intracellular second messenger. J. Cell Biol. 177, 637–45 (2007).Sumitani, S., Goya, K., Testa, J. R., Kouhara, H. & Kasayama, S. Akt1 and Akt2 differently regulate muscle creatine kinase and myogenin gene transcription in insulin-induced differentiation of C2C12 myoblasts. Endocrinology 143, 820–828 (2002).Ohashi, K. et al. Zinc promotes proliferation and activation of myogenic cells via the PI3K/Akt and ERK signaling cascade. Exp. Cell Res. 333, 228–237 (2015).Chesters, J. K. In Zinc in human biology 53, 109–118 (1989).Burattini, S. et al. C2C12 murine myoblasts as a model of skeletal muscle development: Morpho-functional characterization. Eur. J. Histochem. 48, 223–233 (2004).Mnatsakanyan, H. et al. Controlled Assembly of Fibronectin Nanofibrils Triggered by Random Copolymer Chemistry. ACS Appl. Mater. Interfaces 7, 18125–18135 (2015).Jeong, J. & Eide, D. J. The SLC39 family of zinc transporters. Molecular Aspects of Medicine 34, 612–619 (2013).Huang, L., Kirschke, C. P., Zhang, Y. & Yan, Y. Y. The ZIP7 gene (Slc39a7) encodes a zinc transporter involved in zinc homeostasis of the Golgi apparatus. J. Biol. Chem. 280, 15456–15463 (2005).Vallee, B. L. & Falchuk, K. H. The biochemical basis of zinc physiology. Physiological reviews 73 (1993).Ganju, N. & Eastman, A. Zinc inhibits Bax and Bak activation and cytochrome c release induced by chemical inducers of apoptosis but not by death-receptor-initiated pathways. Cell Death Differ. 10, 652–61 (2003).Chai, F., Truong-Tran, A. Q., Ho, L. H. & Zalewski, P. D. Regulation of caspase activation and apoptosis by cellular zinc fluxes and zinc deprivation: A review. Immunol. Cell Biol. 77, 272–278 (1999).Smith, P. J., Wiltshire, M., Furon, E., Beattie, J. H. & Errington, R. J. Impact of overexpression of metallothionein-1 on cell cycle progression and zinc toxicity. Am. J. Physiol. Cell Physiol. 295, C1399–C1408 (2008).Bozym, R. A. et al. Free zinc ions outside a narrow concentration range are toxic to a variety of cells in vitro. Exp. Biol. Med. (Maywood). 235, 741–50 (2010).Plum, L. M., Rink, L. & Hajo, H. The essential toxin: Impact of zinc on human health. Int. J. Environ. Res. Public Health 7, 1342–1365 (2010).Chen, C.-J. & Liao, S.-L. Zinc toxicity on neonatal cortical neurons: involvement of glutathione chelation. J. Neurochem. 85, 443–453 (2003).Chassot, A. A. et al. Confluence-induced cell cycle exit involves pre-mitotic CDK inhibition by p27Kip1 and cyclin D1 downregulation. Cell Cycle 7, 2038–2046 (2008).Spencer, S. L. et al. XThe proliferation-quiescence decision is controlled by a bifurcation in CDK2 activity at mitotic exit. Cell 155, 369–383 (2013).Walsh, K. & Perlman, H. Cell cycle exit upon myogenic differentiation. Curr. Opin. Genet. Dev. 7, 597–602 (1997).Puri, P. L. & Sartorelli, V. Regulation of muscle regulatory factors by DNA-binding, interacting proteins, and post-transcriptional modifications. Journal of Cellular Physiology 185, 155–173 (2000).Zammit, P. S., Partridge, T. A. & Yablonka-Reuveni, Z. The skeletal muscle satellite cell: the stem cell that came in from the cold. J Histochem Cytochem 54, 1177–1191 (2006).McCord, M. C. & Aizenman, E. The role of intracellular zinc release in aging, oxidative stress, and Alzheimer’s disease. Front. Aging Neurosci. 6, 1–16 (2014).Dirksen, R. T. Sarcoplasmic reticulum–mitochondrial through-space coupling in skeletal muscle. This paper is one of a selection of papers published in this Special Issue, entitled 14th International Biochemistry of Exercise Conference – Muscles as Molecular and Metabolic. Appl. Physiol. Nutr. Metab. 34, 389–395 (2009).Groth, C., Sasamura, T., Khanna, M. R., Whitley, M. & Fortini, M. E. Protein trafficking abnormalities in Drosophila tissues with impaired activity of the ZIP7 zinc transporter Catsup. Development 140, 3018–3027 (2013).Ellis, C. D. et al. Zinc and the Msc2 zinc transporter protein are required for endoplasmic reticulum function. J. Cell Biol. 166, 325–335 (2004).Koch, U., Lehal, R. & Radtke, F. Stem cells living with a Notch. Development 140, 689–704 (2013).Gardner, S., Anguiano, M. & Rotwein, P. Defining Akt actions in muscle differentiation. Am. J. Physiol. Physiol. 303, C1292–C1300 (2012).Knight, J. D. & Kothary, R. The myogenic kinome: protein kinases critical to mammalian skeletal myogenesis. Skelet. Muscle 1, 29 (2011).Roth, S. M. Genetic aspects of skeletal muscle strength and mass with relevance to sarcopenia. Bonekey Rep. 1, 1–7 (2012).Mebratu, Y. & Tesfaigzi, Y. How ERK1/2 Activation Controls Cell Proliferation and Cell Death Is Subcellular Localization the Answer? Cell Cycle 8, 1168–1175 (2009)

    p57KIP2 control of actin cytoskeleton dynamics is responsible for its mitochondrial pro-apoptotic effect

    Get PDF
    p57 (Kip2, cyclin-dependent kinase inhibitor 1C), often found downregulated in cancer, is reported to hold tumor suppressor properties. Originally described as a cyclin-dependent kinase (cdk) inhibitor, p57KIP2 has since been shown to influence other cellular processes, beyond cell cycle regulation, including cell death and cell migration. Inhibition of cell migration by p57KIP2 is attributed to the stabilization of the actin cytoskeleton through the activation of LIM domain kinase-1 (LIMK-1). Furthermore, p57KIP2 is able to enhance mitochondrial-mediated apoptosis. Here, we report that the cell death promoting effect of p57KIP2 is linked to its effect on the actin cytoskeleton. Indeed, whereas Jasplakinolide, an actin cytoskeleton-stabilizing agent, mimicked p57KIP2's pro-apoptotic effect, destabilizing the actin cytoskeleton with cytochalsin D reversed p57KIP2's pro-apoptotic function. Conversely, LIMK-1, the enzyme mediating p57KIP2's effect on the actin cytoskeleton, was required for p57KIP2's death promoting effect. Finally, p57KIP2-mediated stabilization of the actin cytoskeleton was associated with the displacement of hexokinase-1, an inhibitor of the mitochondrial voltage-dependent anion channel, from the mitochondria, providing a possible mechanism for the promotion of the mitochondrial apoptotic cell death pathway. Altogether, our findings link together two tumor suppressor properties of p57KIP2, by showing that the promotion of cell death by p57KIP2 requires its actin cytoskeleton stabilization function
    • …
    corecore