19 research outputs found

    Type I Interferons Induce T Regulatory 1 Responses and Restrict Humoral Immunity during Experimental Malaria

    Get PDF
    We thank Christopher Hunter and Bob Axtell for critical feedback, and the Flow Cytometry Laboratory at OUHSC for technical assistance.Author Summary Humoral immunity is essential for host resistance to pathogens that trigger highly inflammatory immune responses, including Plasmodium parasites, the causative agents of malaria. Long-lived, secreted antibody responses depend on a specialized subset of CD4 T cells called T follicular helper (Tfh) cells. However, anti-Plasmodium humoral immunity is often short-lived, non-sterilizing, and immunity rapidly wanes, leaving individuals susceptible to repeated bouts of malaria. Here we explored the relationship between inflammatory type I interferons, the regulation of pathogen-specific CD4 T cell responses, and humoral immunity using models of experimental malaria and systemic virus infection. We identified that type I interferons promote the formation and accumulation of pathogen-specific CD4 T regulatory 1 cells that co-express interferon-gamma and interleukin-10. Moreover, we show that the combined activity of interferon-gamma and interleukin-10 limits the magnitude of infection-induced Tfh responses, the secretion of parasite-specific secreted antibody, and parasite control. Our study provides new insight into the regulation of T regulatory 1 responses and humoral immunity during inflammatory immune reactions against systemic infections.Yeshttp://www.plospathogens.org/static/editorial#pee

    The presence of the cag pathogenicity island is associated with increased superoxide anion radical scavenging activity by Helicobacter pylori

    No full text
    Reactive oxygen species (ROS) generated by Helicobacter pylori infection have been suggested to be important factors in induction of gastric malignancies. Utilizing electron spin resonance spectrometry, H. pylori-dependent radical formation and hydroxyl- and superoxide-anion radical scavenging activity was investigated. In contrast to previous reports, we found that H. pylori does not produce ROS, but displays superoxide scavenging activity. This scavenging activity was increased in cag-positive H. pylori strains when compared to strains lacking an intact cag pathogenicity island, and was dependent on enzyme activity. We hypothesize that the increased scavenging activity of cag-positive H. pylori strains is an adaptation to the increased inflammatory response associated with the cag-positive genotype of H. pylori

    Referenties en concept-maatlatten voor rivieren voor de Kaderrichtlijn Water

    No full text
    In december 2000 is de Europese Kaderrichtlijn Water (KRW) vastgesteld. Eén van de verplichtingen die voortvloeien uit de KRW is het beschrijven van de ecologische referentiesituatie van natuurlijke watertypen, waarvan dit rapport verslag doet voor de categorie Rivieren. Naast de referenties voor de biologische-, hydromorfologische- en algemene fysischchemische kwaliteitselementen per watertype, wordt in dit rapport een voorstel gedaan voor biologische maatlatten ten behoeve van de ecologische beoordeling van natuurlijke wateren. Daarbij is op ecologische gronden een onderscheid in klassen gemaakt, waaronder de Goede Ecologische Toestan

    Embodiment and fundamental motor skills in eSports

    No full text
    Electronic sports (eSports) and other variants of ‘digital sports’ have increased in popularity all over the world and may even come to challenge hegemonic concepts of sport. More relevant than the apparent opposition between ‘physical’ and ‘non-physical’ is the question what kind of embodiment is manifested within virtual environments. In this paper, we argue that eSports do require the learning and performance of motor skills and that embodiment within a virtual environment may be considered playful or even athletic. The type of skills that might be tested can even be considered fundamental movement skills. Under appropriate educational supervision, with knowledge of the game, eSports can be utilized for the development of specific elements of digital literacy. Although motor skills are a defining characteristic of eSports, we do not argue that eSports should be integrated within PE. These arguments have not so much to do with the status of physicality present (or not), but with differences in type of interactions and possibilities for body contact. The visibility of movement behavior, of interactions and rule violations are intrinsically related to the social and pedagogical values of movement education. The direct and visible interaction between learners can be considered important pedagogical tools in PE, when the context of movement education is being understood as broader than just learning sport skills

    Referenties en concept-maatlatten voor rivieren voor de Kaderrichtlijn Water

    No full text
    In december 2000 is de Europese Kaderrichtlijn Water (KRW) vastgesteld. Eén van de verplichtingen die voortvloeien uit de KRW is het beschrijven van de ecologische referentiesituatie van natuurlijke watertypen, waarvan dit rapport verslag doet voor de categorie Rivieren. Naast de referenties voor de biologische-, hydromorfologische- en algemene fysischchemische kwaliteitselementen per watertype, wordt in dit rapport een voorstel gedaan voor biologische maatlatten ten behoeve van de ecologische beoordeling van natuurlijke wateren. Daarbij is op ecologische gronden een onderscheid in klassen gemaakt, waaronder de Goede Ecologische Toestan
    corecore