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Daniel J. J. Carr - One of the best experts on this subject based on the ideXlab platform.

  • PD-L1-Expressing Dendritic Cells Contribute to Viral Resistance during Acute HSV-1 Infection
    Hindawi Limited, 2012
    Co-Authors: Katie M. Bryant-hudson, Daniel J. J. Carr
    Abstract:

    The inhibitory receptor, Programmed Death 1 (PD-1), and its ligands (PD-L1/PD-L2) are thought to play a role in immune surveillance during chronic viral infection. The contribution of the receptor/ligand pair during an acute infection is less understood. To determine the role of PD-L1 and PD-L2 during acute ocular herpes simplex virus type 1 (HSV-1) infection, HSV-1-infected mice administered neutralizing antibody to PD-L1 or PD-L2 were assessed for viral burden and host cellular immune responses. Virus titers were elevated in cornea and trigeminal ganglia (TG) of anti-PD-L1-treated mice which corresponded with a reduced number of CD80-expressing dendritic cells, PD-L1+ dendritic cells, and HSV-1-specific CD8+ T cells within the draining (Mandibular) Lymph Node (MLN). In contrast, anti-PD-L2 treatment had no effect on viral replication or changes in the MLN population. Notably, analysis of CD11c-enriched MLN cells from anti-PD-L1-treated mice revealed impaired functional capabilities. These studies indicate PD-L1-expressing dendritic cells are important for antiviral defense during acute HSV-1 infection

  • A Functional Type I Interferon Pathway Drives Resistance to Cornea Herpes Simplex Virus Type 1 Infection by Recruitment of Leukocytes.
    Journal of biomedical research, 2011
    Co-Authors: Christopher D. Conrady, Heather Jones, Min Zheng, Daniel J. J. Carr
    Abstract:

    Type I interferons are critical antiviral cytokines produced following herpes simplex virus type-1 (HSV-1) infection that act to inhibit viral spread. In the present study, we identify HSV-infected and adjacent uninfected corneal epithelial cells as the source of interferon-α. We also report mice deficient in the A1 chain of the type I IFN receptor (CD118−/−) are extremely sensitive to ocular infection with low doses (100 PFU) of HSV-1 as seen by significantly elevated viral titers in the cornea compared to wild type (WT) controls. The enhanced susceptibility correlated with a loss of CD4+ and CD8+ T cell recruitment and aberrant chemokine production in the cornea despite mounting an adaptive immune response in the draining Mandibular Lymph Node of CD118−/− mice. Taken together, these results highlight the importance of IFN production in both the innate immune response as well as eliciting chemokine production required to facilitate adaptive immune cell trafficking.

  • Research Article PD-L1-Expressing Dendritic Cells Contribute to Viral Resistance during Acute HSV-1 Infection
    2011
    Co-Authors: Katie M. Bryant-hudson, Daniel J. J. Carr
    Abstract:

    Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. The inhibitory receptor, Programmed Death 1 (PD-1), and its ligands (PD-L1/PD-L2) are thought to play a role in immune surveillance during chronic viral infection. The contribution of the receptor/ligand pair during an acute infection is less understood. To determine the role of PD-L1 and PD-L2 during acute ocular herpes simplex virus type 1 (HSV-1) infection, HSV-1-infected mice administered neutralizing antibody to PD-L1 or PD-L2 were assessed for viral burden and host cellular immune responses. Virus titers were elevated in cornea and trigeminal ganglia (TG) of anti-PD-L1-treated mice which corresponded with a reduced number of CD80-expressing dendritic cells, PD-L1 + dendritic cells, and HSV-1-specific CD8 + T cells within the draining (Mandibular) Lymph Node (MLN). In contrast, anti-PD-L2 treatment had no effect on viral replication or changes in the MLN population. Notably, analysis of CD11c-enriched MLN cells from anti-PD-L1-treated mice revealed impaired functional capabilities. These studies indicate PD-L1-expressing dendritic cells are important for antiviral defense during acute HSV-1 infection. 1

  • Loss of Mandibular Lymph Node integrity is associated with an increase in sensitivity to HSV-1 infection in CD118-deficient mice.
    Journal of immunology (Baltimore Md. : 1950), 2009
    Co-Authors: Christopher D. Conrady, Manoj Thapa, Todd Wuest, Daniel J. J. Carr
    Abstract:

    Type I IFNs are potent antiviral cytokines that contribute to the development of the adaptive immune response. To determine the role of type I IFNs in this process in an infectious disease model, mice deficient in the type I IFN receptor (CD118 −/− ) were ocularly infected with HSV-1 and surveyed at times post infection in the nervous system and Lymph Node for virus and the host immune response. Virus titers were elevated in the trigeminal ganglia and brain stem with virus disseminating rapidly to the draining Lymph Node of CD118 −/− mice. T cell and plasmacytoid dendritic cell infiltration into the brain stem was reduced in CD118 −/− mice following infection, which correlated with a reduction in CXCL10 but not CXCL9 expression. In contrast, CXCL1 and CCL2 levels were up-regulated in the brainstem of CD118 −/− mice associated with an increase in F4/80 + macrophages. By day 5 post infection, there was a significant loss in T, NK, and plasmacytoid dendritic cell numbers in the draining Lymph Nodes associated with an increase in apoptotic/necrotic T cells and an appreciable lack of HSV-specific CD8 + T cells. The adoptive transfer of HSV-specific TCR transgenic CD8 + T cells into CD118 −/− mice at the time of infection modestly reduced viral titers in the nervous system suggesting in addition to the generation of HSV-specific CD8 + T cells, other type I IFN-activated pathways are instrumental in controlling acute infection.

D. L. Harris - One of the best experts on this subject based on the ideXlab platform.

  • Acute Infection of Swine by Various Salmonella Serovars
    Journal of food protection, 2004
    Co-Authors: Alan T. Loynachan, J. M. Nugent, Matthew M. Erdman, D. L. Harris
    Abstract:

    The objective of this study was to evaluate the ability of various serovars of Salmonella enterica subsp. enterica to infect alimentary and nonalimentary tissues of swine within 3 h of inoculation. Fourteen wild-type S. enterica serovars (4,12:imonophasic, 6,7 nonmotile, Agona, Brandenburg, Bredeney, Derby, Heidelberg, Infantis, Muenchen, Thompson, Typhimurium, Typhimurium variant Copenhagen, untypeable, and Worthington), two known virulent S. enterica serovars (Choleraesuis strain SC-38 and Typhimurium strain χ4232), and two avirulent S. enterica Choleraesuis vaccine strains (Argus and SC-54) were inoculated intranasally (approximately 5 × 109 cells) into swine (four animals per Salmonella isolate). Three hours after inoculation, animals were euthanized, and both alimentary tissues (tonsil, colon contents, and cecum contents) and nonalimentary tissues (Mandibular Lymph Node, thymus, lung, liver, spleen, ileocecal Lymph Node, and blood) were collected for Salmonella isolation. All Salmonella serovars eval...

  • Virulence determination for rapid extraintestinal Dissemination (Acute Infection) of Common Salmonella Serotypes in Swine
    International Conference on the Epidemiology and Control of Biological Chemical and Physical Hazards in Pigs and Pork, 2001
    Co-Authors: Alan T. Loynachan, J. M. Nugent, Matthew M. Erdman, D. L. Harris
    Abstract:

    Salmonella enterica (Typhimurium and Choleraesuis) have been shown to rapidly disseminate extraintestinally (RED) within 3 hours of intranasal inoculation in pigs (1,2,5,6). Evaluation of RED serotypes may be an important indicator of Salmonella virulence. Experimentally, pigs were challenged with important Lymph Node, fecal, and vaccine isolates of Salmonella and evaluated for RED. These isolates include S. Heidelberg, S. Infantis, S. Derby, S. Worthington, S. 4, 12 imonophasic, S. untypable HL 10416, S. Typhimurium, S. Typhimurium variant Copenhagen, S. Bredeney, S. Muenchen, S. Brandenburg, S. Choleraesuis SC-38, S. Choleraesuis SC-54, and S. Choleraesuis strain Argus. Three hours after intranasal inoculation, the pigs were euthanized, necropsied, and the following tissues were collected for qualitative isolation: tonsil, thymus, blood, Mandibular Lymph Node, lung, spleen, liver, ileocecal Lymph Node, colon contents, and cecum contents. Fewer tissues were positive for vaccine strains compared with wild type or parent strains.

Christian Gortázar - One of the best experts on this subject based on the ideXlab platform.

  • A metaproteomics approach reveals changes in Mandibular Lymph Node microbiota of wild boar naturally exposed to an increasing trend of Mycobacterium tuberculosis complex infection.
    Tuberculosis (Edinburgh Scotland), 2018
    Co-Authors: João Queirós, Christian Gortázar, Vladimir López, Margarita Villar, Joaquín Vicente, Paulo C. Alves, Angélica Hernández-jarguín, Isabel G. Fernández De Mera, José De La ,fuente
    Abstract:

    Abstract Constraints in the characterization of microbiota community that circulates in the host have limited the extent of co-infection studies in natural populations. In this study, we used a metaproteomics approach to characterize the Mandibular Lymph Nodes microbiota of wild boar (Sus scrofa) naturally exposed to an increasing trend of Mycobacterium tuberculosis complex (MTC) infection. Our results showed a reduction in microbiota diversity and changes in the composition, structure and functionality of the microbiota community associated with an increase in tuberculosis prevalence, from 45% in 2002/06 to 83% in 2009/12. These temporal changes were accompanied by an increase in the relative abundance of Babesia, Theileria and Pestivirus genera and a decrease in the Ascogregarina and Chlorella. A positive association was also evidenced between the prevalence of tuberculosis and the presence of microbial proteins responsible for carbohydrate transport and metabolism. Our findings suggest MTC-host-microbiota interactions at the population level, which may occur in order to ensure sufficient metabolic resources for MTC survival, growth and transmission. We strongly recommend the use of metaproteomics when studying microbiota communities in wildlife populations, for which traditional diagnostic techniques are limited and in which new organisms with a pathogenic potential for domestic animals and humans may appear.

  • Validation of proteomics results by Western blot analysis.
    2016
    Co-Authors: Vladimir López, Margarita Villar, João Queirós, Joaquín Vicente, Lourdes Mateos-hernández, Iratxe Díez-delgado, Marinela Contreras, Paulo C. Alves, Pilar Alberdi, Christian Gortázar
    Abstract:

    To validate proteomics results, selected differentially represented immune system proteins were produced in E. coli and used to generate antibodies in rabbits for Western blot analysis of individual wild boar Mandibular Lymph Node protein samples (young TB-, N = 5; young TB+, N = 9; adult TB-, N = 4; adult TB+, N = 5; adult TB++, N = 5). The intensity of protein bands corresponding to test and control RPS14 proteins was determined by densitometric analysis. The intensity of test protein bands was normalized against the intensity of the control band, represented as average + S.D. and compared between groups in adult or young wild boars by a multivariate comparison between the groups using the one-way ANOVA test followed by one-tailed Student’s t-test with Bonferroni correction for samples with unequal variance (p = 0.05). (A) Normalized S100A9 protein levels. (B) Normalized LTF protein levels. (C) Normalized PGLYRP1 protein levels. (D) Comparative analysis of proteomics and Western blot results for differentially represented immune system proteins S100A9, LTF and PGLYRP1.

  • Comparative proteomics of Mandibular Lymph Nodes from M. bovis-infected and uninfected wild boar.
    2016
    Co-Authors: Vladimir López, Margarita Villar, João Queirós, Joaquín Vicente, Lourdes Mateos-hernández, Iratxe Díez-delgado, Marinela Contreras, Paulo C. Alves, Pilar Alberdi, Christian Gortázar
    Abstract:

    Two biological replicates with 2–5 pooled Mandibular Lymph Node samples each were used for comparative proteomics analysis. Identified proteins were grouped according to BP GO using Blast2GO. Within each BP, the average number of PSMs for each S. scrofa protein were added and normalized against the total number of PSMs and compared between infected and uninfected animals by Chi2-test (*p

  • systemic aa amyloidosis in a european wild boar sus scrofa suffering from generalized tuberculosis
    Journal of Veterinary Medicine Series A-physiology Pathology Clinical Medicine, 2005
    Co-Authors: Joaquim Segales, M J M Toussaint, L Lujan, Erik Gruys, J De Vicente, Christian Gortázar
    Abstract:

    Summary An adult female wild boar (Sus scrofa) was found moribund in Cabaneros National Park (central Spain). The animal had a markedly emaciated carcass, with body weight of 25.9 kg. At necropsy, most of the parenchymatous organs had widespread variably sized granulomas. Generalized tuberculosis was confirmed by PCR detection of Mycobacterium bovis in the Mandibular Lymph Node. Large amounts of a hyaline, pale eosinophilic material were observed in liver, kidney and intestine. Congo red staining and green birefringence identified amyloid, which was further classified as AA type based on immunohistochemical results. It is speculated that the abundant serum amyloid A derivatives deposited in the tissues as AA-amyloid may be associated with the generalized tuberculosis. This is the first report of amyloidosis in the European wild boar.

Alan T. Loynachan - One of the best experts on this subject based on the ideXlab platform.

  • Acute Infection of Swine by Various Salmonella Serovars
    Journal of food protection, 2004
    Co-Authors: Alan T. Loynachan, J. M. Nugent, Matthew M. Erdman, D. L. Harris
    Abstract:

    The objective of this study was to evaluate the ability of various serovars of Salmonella enterica subsp. enterica to infect alimentary and nonalimentary tissues of swine within 3 h of inoculation. Fourteen wild-type S. enterica serovars (4,12:imonophasic, 6,7 nonmotile, Agona, Brandenburg, Bredeney, Derby, Heidelberg, Infantis, Muenchen, Thompson, Typhimurium, Typhimurium variant Copenhagen, untypeable, and Worthington), two known virulent S. enterica serovars (Choleraesuis strain SC-38 and Typhimurium strain χ4232), and two avirulent S. enterica Choleraesuis vaccine strains (Argus and SC-54) were inoculated intranasally (approximately 5 × 109 cells) into swine (four animals per Salmonella isolate). Three hours after inoculation, animals were euthanized, and both alimentary tissues (tonsil, colon contents, and cecum contents) and nonalimentary tissues (Mandibular Lymph Node, thymus, lung, liver, spleen, ileocecal Lymph Node, and blood) were collected for Salmonella isolation. All Salmonella serovars eval...

  • Virulence determination for rapid extraintestinal Dissemination (Acute Infection) of Common Salmonella Serotypes in Swine
    International Conference on the Epidemiology and Control of Biological Chemical and Physical Hazards in Pigs and Pork, 2001
    Co-Authors: Alan T. Loynachan, J. M. Nugent, Matthew M. Erdman, D. L. Harris
    Abstract:

    Salmonella enterica (Typhimurium and Choleraesuis) have been shown to rapidly disseminate extraintestinally (RED) within 3 hours of intranasal inoculation in pigs (1,2,5,6). Evaluation of RED serotypes may be an important indicator of Salmonella virulence. Experimentally, pigs were challenged with important Lymph Node, fecal, and vaccine isolates of Salmonella and evaluated for RED. These isolates include S. Heidelberg, S. Infantis, S. Derby, S. Worthington, S. 4, 12 imonophasic, S. untypable HL 10416, S. Typhimurium, S. Typhimurium variant Copenhagen, S. Bredeney, S. Muenchen, S. Brandenburg, S. Choleraesuis SC-38, S. Choleraesuis SC-54, and S. Choleraesuis strain Argus. Three hours after intranasal inoculation, the pigs were euthanized, necropsied, and the following tissues were collected for qualitative isolation: tonsil, thymus, blood, Mandibular Lymph Node, lung, spleen, liver, ileocecal Lymph Node, colon contents, and cecum contents. Fewer tissues were positive for vaccine strains compared with wild type or parent strains.

J. C. Ralston - One of the best experts on this subject based on the ideXlab platform.

  • Polymerase chain reaction amplification of latent Aujeszky's disease virus in dexamethasone treated pigs
    Archives of Virology, 1994
    Co-Authors: K. M. Tham, M. X. J. Motha, G. W. Horner, J. C. Ralston
    Abstract:

    A polymerase chain reaction (PCR) amplification assay was developed for the detection of Aujeszky's disease virus (ADV) DNA in cell cultures and clinical samples. Pigs vaccinated with commercial ADV vaccines and challenged with a field isolate of ADV were immunosuppressed by dexamethasone treatment. Nasal swabs collected from the pigs at various times post-immunosuppression showed that ADV was excreted for at least four to six days starting from day 8 or day 10 following dexamethasone treatment, by virus isolation and/or PCR. However, PCR only detected latent ADV in the trigeminal ganglia, Mandibular Lymph Node, spleen and tonsils, but not in the brain stem, pons and olfactory lobe of two pigs following dexamethasone treatment, whereas tissue explanation and cocultivation failed to demonstrate the presence of the virus.