293 research outputs found

    Increase of cells expressing PD-L1 in bovine leukemia virus infection and enhancement of anti-viral immune responses in vitro via PD-L1 blockade

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    The inhibitory receptor programmed death-1 (PD-1) and its ligand, programmed death-ligand 1 (PD-L1) are involved in immune evasion mechanisms for several pathogens causing chronic infections. Blockade of the PD-1/PD-L1 pathway restores anti-virus immune responses, with concomitant reduction in viral load. In a previous report, we showed that, in bovine leukemia virus (BLV) infection, the expression of bovine PD-1 is closely associated with disease progression. However, the functions of bovine PD-L1 are still unknown. To investigate the role of PD-L1 in BLV infection, we identified the bovine PD-L1 gene, and examined PD-L1 expression in BLV-infected cattle in comparison with uninfected cattle. The deduced amino acid sequence of bovine PD-L1 shows high homology to the human and mouse PD-L1. The proportion of PD-L1 positive cells, especially among B cells, was upregulated in cattle with the late stage of the disease compared to cattle at the aleukemic infection stage or uninfected cattle. The proportion of PD-L1 positive cells correlated positively with prediction markers for the progression of the disease such as leukocyte number, virus load and virus titer whilst on the contrary, it inversely correlated with the degree of interferon-gamma expression. Blockade of the PD-1/PD-L1 pathway in vitro by PD-L1-specific antibody upregulated the production of interleukin-2 and interferon-gamma, and correspondingly, downregulated the BLV provirus load and the proportion of BLV-gp51 expressing cells. These data suggest that PD-L1 induces immunoinhibition in disease progressed cattle during chronic BLV infection. Therefore, PD-L1 would be a potential target for developing immunotherapies against BLV infection

    Comparison of Epirubicin-Iodized Oil Suspension and Emulsion for Transcatheter Arterial Chemoembolization in VX2 Tumor

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    To compare the antitumor efficacy and safety of transcatheter arterial chemoembolization (TACE) by epirubicin suspension (epirubicin suspension: epirubicin-iodized oil mixture without solution) to that by epirubicin emulsion (epirubicin emulsion: epirubicin-iodized oil mixture with solution), the efficacy of treatment by administration of either an epirubicin suspension or emulsion was examined in an animal model. Changes in plasma epirubicin concentration were compared over 24 h immediately after treatment, and enhanced ultrasonographic and histopathological analysis subsequently conducted 7 days after treatment to determine the growth ratio and proportion of viable tumor cells. The growth ratio and proportion of viable tumor cells were found to be significantly lower in the suspension group than in the emulsion group while the plasma epirubicin concentration was found to be significantly higher in the suspension group than in the emulsion group. These results indicate that administration of an epirubicin suspension is a superior form of TACE compared to that of administration of an epirubicin emulsion

    LINE-1 hypomethylation in gastric cancer, detected by bisulfite pyrosequencing, is associated with poor prognosis

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    BACKGROUND: Genome-wide DNA hypomethylation plays an important role in genomic instability and carcinogenesis. DNA methylation in the long interspersed nucleotide element-1, L1 (LINE-1) repetitive element is a good indicator of the global DNA methylation level. In some types of human neoplasms, LINE-1 methylation level is attracting interest as a predictive marker for patient prognosis. However, the prognostic significance of LINE-1 hypomethylation in gastric cancer remains unclear. METHODS: Using 203 resected gastric cancer specimens, we quantified LINE-1 methylation using bisulfite-pyrosequencing technology. A Cox proportional hazards model was used to calculate the hazard ratio (HR), adjusted for the clinical and pathological variables. RESULTS: Gastric cancers showed significantly lower LINE-1 methylation levels compared to matched normal gastric mucosa (p < 0.0001; n = 74). Tumoral LINE-1 methylation range was 11.6–97.5 on a 0–100 scale (n = 203; mean 71.4, median 74.4, standard deviation 12.9). LINE-1 hypomethylation was significantly associated with shorter overall survival [log-rank p = 0.029; univariate HR 2.01, 95 % confidence interval (CI) 1.09–3.99, p = 0.023; stage-matched HR 1.88, 95 % CI 1.02–3.74, p = 0.041; multivariate HR 1.98, 95 % CI 1.04–4.04, p = 0.036]. No significant effect modification was observed by any of the covariates in survival analysis (all p interaction >0.25). CONCLUSIONS: LINE-1 hypomethylation in gastric cancer is associated with shorter survival, suggesting that it has potential for use as a prognostic biomarker

    Distinct polymorphisms in a single herpesvirus gene are capable of enhancing virulence and mediating vaccinal resistance

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    Modified-live herpesvirus vaccines are widely used in humans and animals, but field strains can emerge that have a higher virulence and break vaccinal protection. Since the introduction of the first vaccine in the 1970s, Marek's disease virus overcame the vaccine barrier by the acquisition of numerous genomic mutations. However, the evolutionary adaptations in the herpesvirus genome responsible for the vaccine breaks have remained elusive. Here, we demonstrate that point mutations in the multifunctional meq gene acquired during evolution can significantly alter virulence. Defined mutations found in highly virulent strains also allowed the virus to overcome innate cellular responses and vaccinal protection. Concomitantly, the adaptations in meq enhanced virus shedding into the environment, likely providing a selective advantage for the virus. Our study provides the first experimental evidence that few point mutations in a single herpesviral gene result in drastically increased virulence, enhanced shedding, and escape from vaccinal protection

    Acceptedfor publicationMay 19

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    ABSTRACT We and other investigators obtained evidence that platelets stimulate endothelin-i (ET-i) production at both message and protein levels in vascular endothelial cells (EC5),and that plate let-derived transforming growth factor-f31 (TGF-j3i) is respon sible for this stimulation. In the present study, we examined the effects of acidification or heat treatment, known to activate latent TGF-f31, on the platelet supernatant-induced Er-i pro duction in cultured porcine aortic ECs. Supematant of platelets (6.0 x 1O@ platelets/mI) aggregated by adenosine diphosphate contained large amounts of TGF-pi, but were almost in a latent form, and the proportion of active TGF-j31 in the supematant was increased markedly in the case of acidification or heat treatment. These treatments also significantly potentiated the supematant-induced stimulation of prepro Er-i mRNA expres sion and the Er-i release in ECs. Purified TGF-@i also en hanced Er-i release, dose-dependently, but the enhancement declined at the higher concentrations. Thus, powerful stimula tion of Er-i production by platelet supematant after acidifica tion or heat treatment cannot be explained only by increments in active TGF-131. The supematant-induced stimulation of Er-i synthesis was significantly inhibited by concomitant treatment of TGF-@i neutralizing antibody, but this inhibition was incom plete even at a concentration that abolished TGF-31 -induced maximal stimulation. These resutts suggest that platelet-induced stimulation and subsequent acidification and heat treatment induced potentiation on endothelial Er-i production depend closely on release and activation of TGF-@i derived from plate lets. However, when TGF-fii concentration is increased, this peptide may further stimulate Er-i production, probably through interactions with other platelet-derived substances

    Guideline from Japanese Society of Echocardiography : 2018 focused update incorporated into Guidance for the Management and Maintenance of Echocardiography Equipment

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    Echocardiography plays a pivotal role as an imaging modality in the modern cardiology practice. Information derived from echocardiography is definitely helpful for a patient care. The Japanese Society of Echocardiography has promoted echocardiography for a routine clinical and research use. One of the missions of the Society is to provide information that is useful for high-quality examinations. To ensure it, we believe equipment in good conditions and a comfortable environment are important for both a patient and an examiner. Thus, the Committee for Guideline Writing, the Japanese Society of Echocardiography published brief guidance for the routine use of echocardiography equipment in 2015. Recently, the importance of international standardization has been emphasized in the medical laboratories. Accordingly, the committee has revised and updated our guidance for the routine use of echocardiography equipment

    Potential of ferritin 2 as an antigen for the development of a universal vaccine for avian mites, poultry red mites, tropical fowl mites, and northern fowl mites

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    IntroductionPoultry red mites (PRMs, Dermanyssus gallinae), blood-sucking ectoparasites, are a threat to the poultry industry because of reduced production caused by infestation. In addition, tropical fowl mites (TFMs, Ornithonyssus bursa) and northern fowl mites (NFMs, Ornithonyssus sylviarum) are hematophagous, distributed in various regions, genetically and morphologically close to PRMs, and cause similar problems to the poultry industry. Vaccine approaches have been studied for PRM control, and several molecules have been identified in PRMs as candidates for effective vaccine antigens. The development of an anti-PRM vaccine as a universal vaccine with broad efficacy against avian mites could improve the productivity of poultry farms worldwide. Molecules that are highly conserved among avian mites and have critical functions in the physiology and growth of mites could be ideal antigen candidates for the development of universal vaccines. Ferritin 2 (FER2), an iron-binding protein, is critical for the reproduction and survival of PRMs and has been reported as a useful vaccine antigen for the control of PRMs and a candidate for the universal vaccine antigen in some tick species.Method and resultsHerein, we identified and characterized FER2 in TFMs and NFM. Compared with the sequence of PRM, the ferroxidase centers of the heavy chain subunits were conserved in FER2 of TFMs and NFMs. Phylogenetic analysis revealed that FER2 belongs to clusters of secretory ferritins of mites and other arthropods. Recombinant FER2 (rFER2) proteins from PRMs, TFMs, and NFMs exhibited iron-binding abilities. Immunization with each rFER2 induced strong antibody responses in chickens, and each immune plasma cross-reacted with rFER2 from different mites. Moreover, mortality rates of PRMs fed with immune plasma against rFER2 from TFMs or NFMs, in addition to PRMs, were higher than those of control plasma.DiscussionrFER2 from each avian mite exhibited anti-PRM effects. This data suggests that it has the potential to be used as an antigen candidate for a universal vaccine against avian mites. Further studies are needed to access the usefulness of FER2 as a universal vaccine for the control of avian mites
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