73 research outputs found

    Macrophages mediate the anti-tumor effects of the oncolytic virus HSV1716 in mammary tumors

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    Oncolytic viruses (OV) have been shown to activate the anti-tumor functions of specific immune cells like T cells. Here, we show OV can also reprogram TAMs to a less immunosuppressive phenotype. Syngeneic, immunocompetent mouse models of primary breast cancer were established using PyMT-TS1, 4T1 and E0771 cell lines and a metastatic model of breast cancer was established using the 4T1 cell line. Tumor growth and overall survival was assessed following intravenous administration of the OV, HSV1716 (a modified herpes simplex virus). Infiltration and function of various immune effector cells was assessed by NanoString, flow cytometry of dispersed tumors and immunofluorescence analysis of tumor sections. HSV1716 administration led to marked tumor shrinkage in primary mammary tumors and a decrease in metastases. This was associated with a significant increase in the recruitment/activation of cytotoxic T cells, a reduction in the presence of regulatory T cells and the reprograming of TAMs towards a pro-inflammatory, less immunosuppressive phenotype. These findings were supported by in vitro data demonstrating that human monocyte-derived macrophages (MDMs) host HSV1716 replication, and that this led to immunogenic macrophage lysis. These events were dependent on macrophage expression of proliferating cell nuclear antigen (PCNA). Finally, the anti-tumor effect of OV was markedly diminished when TAMs were depleted using clodronate liposomes. Together, our results show that TAMs play an essential role in support of the tumoricidal effect of the OV, HSV1716 - they both host viral replication via a novel, PCNA-dependent mechanism and are reprogramed to express a less immunosuppressive phenotype

    Factorization at Subleading Power and Irreducible Uncertainties in BˉXsγ\bar B\to X_s\gamma Decay

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    Using methods from soft-collinear and heavy-quark effective theory, a systematic factorization analysis is performed for the BˉXsγ\bar B\to X_s\gamma photon spectrum in the endpoint region mb2Eγ=O(ΛQCD)m_b-2E_\gamma={\cal O}(\Lambda_{\rm QCD}). It is proposed that, to all orders in 1/mb1/m_b, the spectrum obeys a novel factorization formula, which besides terms with the structure HJSH\,J\otimes S familiar from inclusive BˉXulνˉ\bar B\to X_u l\,\bar\nu decay distributions contains "resolved photon" contributions of the form HJSJˉH\,J\otimes S\otimes\bar J and HJSJˉJˉH\,J\otimes S\otimes\bar J\otimes\bar J. Here SS and Jˉ\bar J are new soft and jet functions, whose form is derived. These contributions arise whenever the photon couples to light partons instead of coupling directly to the effective weak interaction. The new contributions appear first at order 1/mb1/m_b and are related to operators other than Q7γQ_{7\gamma} in the effective weak Hamiltonian. They give rise to non-vanishing 1/mb1/m_b corrections to the total decay rate, which cannot be described using a local operator product expansion. A systematic analysis of these effects is performed at tree level in hard and hard-collinear interactions. The resulting uncertainty on the decay rate defined with a cut Eγ>1.6E_\gamma>1.6 GeV is estimated to be approximately ±5\pm 5%. It could be reduced by an improved measurement of the isospin asymmetry Δ0\Delta_{0-} to the level of ±4\pm 4%. We see no possibility to reduce this uncertainty further using reliable theoretical methods.Comment: 63 pages, 11 Figures, Journal Versio

    Infant High-Grade Gliomas Comprise Multiple Subgroups Characterized by Novel Targetable Gene Fusions and Favorable Outcomes.

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    Infant high-grade gliomas appear clinically distinct from their counterparts in older children, indicating that histopathologic grading may not accurately reflect the biology of these tumors. We have collected 241 cases under 4 years of age, and carried out histologic review, methylation profiling, and custom panel, genome, or exome sequencing. After excluding tumors representing other established entities or subgroups, we identified 130 cases to be part of an "intrinsic" spectrum of disease specific to the infant population. These included those with targetable MAPK alterations, and a large proportion of remaining cases harboring gene fusions targeting ALK (n = 31), NTRK1/2/3 (n = 21), ROS1 (n = 9), and MET (n = 4) as their driving alterations, with evidence of efficacy of targeted agents in the clinic. These data strongly support the concept that infant gliomas require a change in diagnostic practice and management. SIGNIFICANCE: Infant high-grade gliomas in the cerebral hemispheres comprise novel subgroups, with a prevalence of ALK, NTRK1/2/3, ROS1, or MET gene fusions. Kinase fusion-positive tumors have better outcome and respond to targeted therapy clinically. Other subgroups have poor outcome, with fusion-negative cases possibly representing an epigenetically driven pluripotent stem cell phenotype.See related commentary by Szulzewsky and Cimino, p. 904.This article is highlighted in the In This Issue feature, p. 890

    Taming the tiger by the tail: modulation of DNA damage responses by telomeres

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    Telomeres are by definition stable and inert chromosome ends, whereas internal chromosome breaks are potent stimulators of the DNA damage response (DDR). Telomeres do not, as might be expected, exclude DDR proteins from chromosome ends but instead engage with many DDR proteins. However, the most powerful DDRs, those that might induce chromosome fusion or cell-cycle arrest, are inhibited at telomeres. In budding yeast, many DDR proteins that accumulate most rapidly at double strand breaks (DSBs), have important functions in physiological telomere maintenance, whereas DDR proteins that arrive later tend to have less important functions. Considerable diversity in telomere structure has evolved in different organisms and, perhaps reflecting this diversity, different DDR proteins seem to have distinct roles in telomere physiology in different organisms. Drawing principally on studies in simple model organisms such as budding yeast, in which many fundamental aspects of the DDR and telomere biology have been established; current views on how telomeres harness aspects of DDR pathways to maintain telomere stability and permit cell-cycle division are discussed

    Leakage of nitrous oxide emissions within the Spanish agro-food system in 1961-2009

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    Abstract In this paper we examine the trends of nitrous oxide (N2O) emissions of the Spanish agricultural sector related to national production and consumption in the 1961?2009 period.The comparison between production- and consumption-based emissions at the national level provides a complete overview of the actual impact resulting from the dietary choices of a given country and allows the evaluation of potential emission leakages. On average, 1.5 % of the new reactive nitrogen that enters Spain every year is emitted as N2O. Production- and consumption-based emissions have both significantly increased in the period studied and nowadays consumption-based emissions are 45 % higher than production-based emissions. A large proportion of the net N2O emissions associated with imported agricultural godos comes from countries that are not committers for the United Nations Framework Convention on Climate Change Kyoto Protocol Annex I. An increase in feed consumption is the main driver of the changes observed, leading to a arkable emission leakage in the Spanish agricultural sector. The complementary approach used here is essential to achieve an effective mitigation of Spanish greenhouse gas emissions

    Changing trends in mastitis

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    <p>Abstract</p> <p>The global dairy industry, the predominant pathogens causing mastitis, our understanding of mastitis pathogens and the host response to intramammary infection are changing rapidly. This paper aims to discuss changes in each of these aspects. Globalisation, energy demands, human population growth and climate change all affect the dairy industry. In many western countries, control programs for contagious mastitis have been in place for decades, resulting in a decrease in occurrence of <it>Streptococcus agalactiae </it>and <it>Staphylococcus aureus </it>mastitis and an increase in the relative impact of <it>Streptococcus uberis </it>and <it>Escherichia coli </it>mastitis. In some countries, <it>Klebsiella </it>spp. or <it>Streptococcus dysgalactiae </it>are appearing as important causes of mastitis. Differences between countries in legislation, veterinary and laboratory services and farmers' management practices affect the distribution and impact of mastitis pathogens. For pathogens that have traditionally been categorised as contagious, strain adaptation to human and bovine hosts has been recognised. For pathogens that are often categorised as environmental, strains causing transient and chronic infections are distinguished. The genetic basis underlying host adaptation and mechanisms of infection is being unravelled. Genomic information on pathogens and their hosts and improved knowledge of the host's innate and acquired immune responses to intramammary infections provide opportunities to expand our understanding of bovine mastitis. These developments will undoubtedly contribute to novel approaches to mastitis diagnostics and control.</p
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