The Endogenous Th17 Response in NO<inf>2</inf>-Promoted Allergic Airway Disease Is Dispensable for Airway Hyperresponsiveness and Distinct from Th17 Adoptive Transfer

Severe, glucocorticoid-resistant asthma comprises 5-7% of patients with asthma. IL-17 is a biomarker of severe asthma, and the adoptive transfer of Th17 cells in mice is sufficient to induce glucocorticoid-resistant allergic airway disease. Nitrogen dioxide (NO2) is an environmental toxin that correlates with asthma severity, exacerbation, and risk of adverse outcomes. Mice that are allergically sensitized to the antigen ovalbumin by exposure to NO2 exhibit a mixed Th2/Th17 adaptive immune response and eosinophil and neutrophil recruitment to the airway following antigen challenge, a phenotype reminiscent of severe clinical asthma. Because IL-1 receptor (IL-1R) signaling is critical in the generation of the Th17 response in vivo, we hypothesized that the IL-1R/Th17 axis contributes to pulmonary inflammation and airway hyperresponsiveness (AHR) in NO2-promoted allergic airway disease and manifests in glucocorticoid-resistant cytokine production. IL-17A neutralization at the time of antigen challenge or genetic deficiency in IL-1R resulted in decreased neutrophil recruitment to the airway following antigen challenge but did not protect against the development of AHR. Instead, IL-1R-/- mice developed exacerbated AHR compared to WT mice. Lung cells from NO2-allergically inflamed mice that were treated in vitro with dexamethasone (Dex) during antigen restimulation exhibited reduced Th17 cytokine production, whereas Th17 cytokine production by lung cells from recipient mice of in vitro Th17-polarized OTII T-cells was resistant to Dex. These results demonstrate that the IL-1R/Th17 axis does not contribute to AHR development in NO2-promoted allergic airway disease, that Th17 adoptive transfer does not necessarily reflect an endogenously-generated Th17 response, and that functions of Th17 responses are contingent on the experimental conditions in which they are generated. © 2013 Martin et al

Practical Application of Methanol-Mediated Mutualistic Symbiosis between Methylobacterium Species and a Roof Greening Moss, Racomitrium japonicum

Bryophytes, or mosses, are considered the most maintenance-free materials for roof greening. Racomitrium species are most often used due to their high tolerance to desiccation. Because they grow slowly, a technology for forcing their growth is desired. We succeeded in the efficient production of R. japonicum in liquid culture. The structure of the microbial community is crucial to stabilize the culture. A culture-independent technique revealed that the cultures contain methylotrophic bacteria. Using yeast cells that fluoresce in the presence of methanol, methanol emission from the moss was confirmed, suggesting that it is an important carbon and energy source for the bacteria. We isolated Methylobacterium species from the liquid culture and studied their characteristics. The isolates were able to strongly promote the growth of some mosses including R. japonicum and seed plants, but the plant-microbe combination was important, since growth promotion was not uniform across species. One of the isolates, strain 22A, was cultivated with R. japonicum in liquid culture and in a field experiment, resulting in strong growth promotion. Mutualistic symbiosis can thus be utilized for industrial moss production

Mitochondrial Localized STAT3 Is Involved in NGF Induced Neurite Outgrowth

Background: Signal transducer and activator of transcription 3 (STAT3) plays critical roles in neural development and is increasingly recognized as a major mediator of injury response in the nervous system. Cytokines and growth factors are known to phosphorylate STAT3 at tyrosine 705 with or without the concomitant phosphorylation at serine 727, resulting in the nuclear localization of STAT3 and subsequent transcriptional activation of genes. Recent evidence suggests that STAT3 may control cell function via alternative mechanisms independent of its transcriptional activity. Currently, the involvement of STAT3 mono-phosphorylated at residue serine 727 (P-Ser-STAT3) in neurite outgrowth and the underlying mechanism is largely unknown. Principal Findings: In this study, we investigated the role of nerve growth factor (NGF) induced P-Ser-STAT3 in mediating neurite outgrowth. NGF induced the phosphorylation of residue serine 727 but not tyrosine 705 of STAT3 in PC12 and primary cortical neuronal cells. In PC12 cells, serine but not tyrosine dominant negative mutant of STAT3 was found to impair NGF induced neurite outgrowth. Unexpectedly, NGF induced P-Ser-STAT3 was localized to the mitochondria but not in the nucleus. Mitochondrial STAT3 was further found to be intimately involved in NGF induced neurite outgrowth and the production of reactive oxygen species (ROS). Conclusion: Taken together, the findings herein demonstrated a hitherto unrecognized novel transcription independen

Safety and effectiveness of switching from infliximab to etanercept in patients with rheumatoid arthritis: results from a large Japanese postmarketing surveillance study

Finding an effective treatment strategy for rheumatoid arthritis (RA) patients who have not benefited from previous tumor necrosis factor–α antagonist treatment is important for minimizing RA disease activity and improving patient outcomes. The aim of this study was to compare the safety and effectiveness of etanercept in patients with and without infliximab (IFX) treatment experience. Patients (n = 7,099) from a large postmarketing observational study of etanercept use in Japan were divided into 2 cohorts based on previous IFX use (pre-IFX and non-IFX). Baseline characteristics were assessed in each cohort. Adverse events (AEs) and European League Against Rheumatism (EULAR) responses were monitored every 4 weeks for 24 weeks. At baseline, pre-IFX patients were younger and had fewer comorbidities and a shorter RA duration than non-IFX patients. During the study, pre-IFX patients received concomitant methotrexate more often than non-IFX patients. The incidence of AEs and serious AEs were significantly lower in pre-IFX patients, as was the percentage of patients who discontinued treatment. Both cohorts had significant improvement (P < 0.001) in EULAR responses at the end of the treatment period. This study demonstrated that etanercept was effective and well tolerated in active RA patients with and without prior IFX treatment

IL-33 Induces IL-9 Production in Human CD4+ T Cells and Basophils

IL-33, an IL-1 family member and ligand for the IL-1 receptor-related protein ST2, has been associated with induction of Th2 cytokines such as IL-4, IL-5, and IL-13. Here, we report that IL-33 can initiate IL-9 protein secretion in vitro in human CD4+ T cells and basophils isolated from peripheral blood. TGF-β has been described as a critical factor for IL-9 induction in Th2 cells; however, we found that TGF-β also induces co-production of IL-9 in purified, naïve (>99%) CD4+CD45RA+CD45RO−CD25− T cells differentiated towards a Th1 profile. Subsequently, it was demonstrated that TGF-β is important, although not an absolute requirement, for IL-9 production in CD4+ T cells. IL-9 production by purified (>95%) human basophils, cultured for 24 h with IL-3 or IL-33, was found, with a strong synergy between the two, likely to be explained by the IL-3 upregulated ST2 expression. Collectively, these data indicate that barrier functioning cells are important for the regulation of IL-9 production by immune cells in inflamed tissue

Safety and effectiveness responses to etanercept for rheumatoid arthritis in Japan: a sub-analysis of a post-marketing surveillance study focusing on the duration of rheumatoid arthritis

The aim is to investigate the relationship of duration of rheumatoid arthritis (RA) with safety and effectiveness of etanercept (ETN) in Japan. Post-marketing surveillance data for 7,099 patients treated with ETN were analyzed. Baseline characteristics, treatment effectiveness, incidence of adverse events (AEs), and serious AEs (SAEs) in relation to duration of RA were studied. At baseline, patients with RA for longer duration were older, weighed less, had more comorbidities, allergies, and corticosteroid use, but smoked less and had less morning stiffness. By 2–5 years with RA, more than half of the patients had advanced to Steinbrocker radiographic stage III or IV. Methotrexate (MTX) was the most commonly used pre-treatment disease-modifying antirheumatic drug; however, concomitant MTX use and its dose were lower among patients with longer duration of RA. Remission rates (26.6%) were greatest among patients having RA for <2 years. Less AEs and SAEs were observed among patients with shorter duration of RA. These results suggest that RA treatment in Japan in the era pre-biologics may not have been adequate to control disease activity and prevent joint destruction. Patients with shorter duration of RA may have better physical status which allows the opportunity to treat more intensively putting a higher percentage of patients in remission and possibly decreasing exposure to SAEs