Publications by authors named "Jason D Price"

Loss-of-function mutations have provided crucial insights into the immunoregulatory actions of Foxp3+ regulatory T cells (Tregs). By contrast, we know very little about the consequences of defects that amplify aspects of Treg function or differentiation. Here we show that mice heterozygous for an Ikbkb gain-of-function mutation develop psoriasis.

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Inflammasome signaling is a central pillar of innate immunity triggering inflammation and cell death in response to microbes and danger signals. Here, we show that two virulence factors from the human bacterial pathogen Clostridium perfringens are nonredundant activators of the NLRP3 inflammasome in mice and humans. C.

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Merozoite surface protein 2 (MSP2) is a highly abundant, GPI-anchored surface antigen on merozoites of the malaria parasite Plasmodium falciparum. It consists of highly conserved N- and C-terminal domains, and a central polymorphic region that allows all MSP2 alleles to be categorized into the 3D7 or FC27 family. Previously it has been shown that epitope accessibility differs between lipid-bound and lipid-free MSP2, suggesting that lipid interactions modulate the conformation and antigenicity in a way that may better mimic native MSP2 on the merozoite surface.

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Inflammasomes are important for host defence against pathogens and homeostasis with commensal microbes. Here, we show non-haemolytic enterotoxin (NHE) from the neglected human foodborne pathogen Bacillus cereus is an activator of the NLRP3 inflammasome and pyroptosis. NHE is a non-redundant toxin to haemolysin BL (HBL) despite having a similar mechanism of action.

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Host recognition of microbial components is essential in mediating an effective immune response. Cytosolic bacteria must secure entry into the host cytoplasm to facilitate replication and, in doing so, liberate microbial ligands that activate cytosolic innate immune sensors and the inflammasome. Here, we identified a multicomponent enterotoxin, haemolysin BL (HBL), that engages activation of the inflammasome.

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Introduction: In this phase I study using a 3 + 3 dose escalation design, the safety, dose-limiting toxicity (DLT), immunogenicity and efficacy of intravenous Lipovaxin-MM-a multi-component dendritic cell-targeted liposomal vaccine against metastatic melanoma-was investigated.

Methods: Twelve subjects with metastatic cutaneous melanoma were recruited in three cohorts. Patients in Cohort A (n = 3) and Cohort B (n = 3) received three doses of 0.

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Cholera toxin (CT) is a mucosal adjuvant capable of inducing strong immune responses to co-administered antigens following oral or intranasal immunization of mice. To date, the direct effect of CT on antigen-specific CD4(+) T cell migration and proliferation profiles in vivo is not well characterized. In this study, the effect of CT on the migration pattern and proliferative responses of adoptively transferred, CD4(+) TCR transgenic T cells in orally or intranasally vaccinated mice, was analyzed by flow cytometry.

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Celiac disease is a chronic inflammatory enteropathy caused by cellular immunity to dietary gluten. More than 90% of patients carry HLA-DQ2 encoded by HLA-DQA1*05 and DQB1*02, and gluten-specific CD4(+) T cells from intestinal biopsies of these patients are HLA-DQ2-restricted, produce Th1 cytokines and preferentially recognize gluten peptides deamidated by tissue transglutaminase. We generated mice lacking murine MHC class II genes that are transgenic for human CD4 and the autoimmunity and celiac disease-associated HLA-DR3-DQ2 haplotype.

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Helicobacter pylori is the etiological agent of human chronic gastritis, a condition seen as a precursor to the development of gastrointestinal ulcers or gastric cancer. This study utilized the murine model of chronic H. pylori infection to characterize the role of macrophages in the induction of specific immune responses and gastritis and in the control of the bacterial burden following H.

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Interleukin-12 (IL-12) and IL-18 are both central to the induction of gamma interferon (IFN-gamma), and various roles for IL-12 and IL-18 in control of intracellular microbial infections have been demonstrated. We used IL-12p40(-/-) and IL-18(-/-) mice to further investigate the role of IL-12 and IL-18 in control of Salmonella enterica serovar Typhimurium. While C57BL/6 and IL-18(-/-) mice were able to resolve attenuated S.

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The humoral response to the gastrointestinal (GI) flora was analyzed in secretory Ig (sIg)-deficient polymeric IgR (pIgR)(-/-) mice and otherwise congenic C57BL/6 mice. While both strains carried an ileal flora of similar size and composition, increased bacterial translocation to mesenteric lymph node was demonstrated in pIgR(-/-) mice. Serum IgA was greatly increased in pIgR(-/-) mice compared with C57BL/6 mice and reacted with commensal organisms and food.

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A major hurdle in designing successful epitope-based vaccines resides in the delivery, stability, and immunogenicity of the peptide immunogen. The short-lived nature of unmodified peptide-based vaccines in vivo limits their therapeutic application in the immunotherapy of cancers and chronic viral infections as well as their use in generating prophylactic immunity. The incorporation of beta-amino acids into peptides decreases proteolysis, yet its potential application in the rational design of T cell mimotopes is poorly understood.

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Gene expression in murine dendritic cells (DCs) infected with green fluorescent protein-expressing Salmonella enterica serovar Typhimurium BRD509 was studied by mRNA differential display. Infected DCs were sorted from uninfected cells by flow cytometry. The mRNA expression patterns of infected and uninfected cells revealed a number of differentially expressed transcripts, which included the macrophage-derived chemokine (MDC).

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