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The adoptive transfer of OVA-specific Th1 cells into WT mice followed by OVA inhalation induces a significant elevation of airway hyper-responsiveness (AHR) with neutrophilia but not mucus hypersecretion. Here, we demonstrate that the airway inflammation model, pathogenically characterized as severe asthma, was partly mimicked by i.n. administration of IFN-γ. The administration of IFN-γ instead of Th1 cells caused AHR elevation but not neutrophilia, and remarkably induced neurokinin-2 receptor (NK2R) expression along with neurokinin A (NKA) production in the lung. To evaluate whether NKA/NK2R was involved in airway inflammation, we first investigated the role of NKA/NK2R-signaling in airway smooth muscle cells (ASMCs) in vitro. NK2R mRNA expression was significantly augmented in tracheal tube-derived ASMCs of WT mice but not STAT-1−/− mice after stimulation with IFN-γ. In addition, methacholine-mediated Ca2+ influx into the ASMCs was significantly reduced in the presence of NK2R antagonist. Moreover, the NK2R antagonist strongly inhibited IFN-γ-dependent AHR elevation in vivo. Thus, these results demonstrated that IFN-γ directly acts on ASMCs to elevate AHR via the NKA/NK2R-signaling cascade. Our present findings suggested that NK2R-mediated neuro-immuno crosstalk would be a promising target for developing novel drugs in Th1-cell-mediated airway inflammation, including severe asthma. [ABSTRACT FROM AUTHOR]

Background: Janus kinases (JAKs) are regulators of signaling through cytokine receptors. The importance of JAK1/3 signaling on TH2 differentiation and development of lung allergic responses has not been investigated. Objective: We sought to examine a selective JAK1/3 inhibitor (R256) on differentiation of TH subsets in vitro and on development of ovalbumin (OVA)–induced airway hyperresponsiveness (AHR) and inflammation in an experimental model of asthma. Methods: A selective JAK1/3 inhibitor was used to assay the importance of this pathway on induction of TH1, TH2, and TH17 differentiation in vitro. In vivo, the effects of inhibiting JAK1/3 signaling were examined by administering the inhibitor during the sensitization or allergen challenge phases in the primary challenge model or just before provocative challenge in the secondary challenge model. Airway inflammation and AHR were examined after the last airway challenge. Results: In vitro, R256 inhibited differentiation of TH2 but not TH1 or TH17 cells, which was associated with downregulation of signal transducer and activator of transcription (STAT) 6 and STAT5 phosphorylation. However, once polarized, TH2 cells were unaffected by the inhibitor. In vivo, R256 administered during the OVA sensitization phase prevented the development of AHR, airway eosinophilia, mucus hypersecretion, and TH2 cytokine production without changes in TH1 and TH17 cytokine levels, indicating that selective blockade of TH2 differentiation was critical. Inhibitor administration after OVA sensitization but during the challenge phases in the primary or secondary challenge models similarly suppressed AHR, airway eosinophilia, and mucus hypersecretion without any reduction in TH2 cytokine production, suggesting the inhibitory effects were downstream of TH2 cytokine receptor signaling pathways. Conclusions: Targeting the TH2-dependent JAK/STAT activation pathway represents a novel therapeutic approach for the treatment of asthma. [Copyright &y& Elsevier]

Background: The provirus integration site for Moloney murine leukemia virus (Pim) 1 kinase is an oncogenic serine/threonine kinase implicated in cytokine-induced cell signaling, whereas Runt-related transcription factor (Runx) has been implicated in the regulation of T-cell differentiation. The interaction of Pim1 kinase and Runx3 in the pathogenesis of peanut allergy has not been defined. Objectives: We sought to determine the effects of Pim1 kinase modulation on Runx3 expression and TH2 and TH17 cell function in an experimental model of peanut allergy. Methods: A Pim1 kinase inhibitor was administered to peanut-sensitized and challenged wild-type and Runx3 +/− mice. Symptoms, intestinal inflammation, and Pim1 kinase and Runx3 mRNA expression and protein levels were assessed. The effects of Pim1 kinase inhibition on TH1, TH2, and TH17 differentiation in vivo and in vitro were also determined. Results: Peanut sensitization and challenge resulted in accumulation of inflammatory cells and goblet cell metaplasia and increased levels of Pim1 kinase and TH2 and TH17 cytokine production but decreased levels of Runx3 mRNA and protein in the small intestines of wild-type mice. All of these findings were normalized with Pim1 kinase inhibition. In sensitized and challenged Runx3 +/− mice, inhibition of Pim1 kinase had less effect on the development of the full spectrum of intestinal allergic responses. In vitro inhibition of Pim1 kinase attenuated TH2 and TH17 cell differentiation and expansion while maintaining Runx3 expression in T-cell cultures from wild-type mice; these effects were reduced in T-cell cultures from Runx3 +/− mice. Conclusion: These data support a novel regulatory axis involving Pim1 kinase and Runx3 in the control of food-induced allergic reactions through the regulation of TH2 and TH17 differentiation. [Copyright &y& Elsevier]

Mesenchymal stem cells (MSC) exert immune modulatory properties and previous studies demonstrated suppressive effects of MSC treatment in animal models of allergic airway inflammation. However, the underlying mechanisms have not been fully elucidated. We studied the role of MSC in immune activation and subsequent recruitment of monocytes in suppressing airway hyperresponsiveness and airway inflammation using a mouse model of allergic airway inflammation. MSC administration prior to or after allergen challenge inhibited the development of airway inflammation in allergen-sensitized mice. This was accompanied by an influx of CCR2-positive monocytes, which were localized around injected MSC in the lungs. Notably, IL-10-producing monocytes and/or macrophages were also increased in the lungs. Systemic administration of liposomal clodronate or a CCR2 antagonist significantly prevented the suppressive effects of MSC. Activation of MSC by IFN-γ leading to the upregulation of CCL2 expression was essential for the suppressive effects, as administration of wild-type MSC into IFN-γ-deficient recipients, or IFN-γ receptor-deficient or CCL2-deficient MSC into wild-type mice failed to suppress airway inflammation. These results suggest that MSC activation by IFN-γ, followed by increased expression of CCL2 and recruitment of monocytes to the lungs, is essential for suppression by MSC in allergen-induced airway hyperresponsiveness and airway inflammation. [ABSTRACT FROM AUTHOR]

Food allergy prevalence is increasing all over the world. Recent epidemiologic studies have shown the link between vitamin D 3 insufficiency and food allergy occurrence. In this study, we investigated the effect of supplementation with cholecalciferol, a widely used form of vitamin D 3 , on food allergy using an experimental mouse model. In wild-type BALB/c mice which were sensitized and challenged with an experimental allergen, ovalbumin, a clinical symptom of food allergy, diarrhea, was significantly induced with the elevation of immunoglobulin E level and the increases of T helper 2 cytokine productions, such as interleukin-4, -5, and -13 (p<0.05), whereas no change in T helper 1 cytokine production, such as interferon-γ, was observed. It was also found that cell population of CD69 + CD4 + T cells was increased slightly in spleen and significantly in the mesenteric lymphnode with the diarrheal symptom (p<0.05). Treatment of cholecalciferol reduced the allergic diarrhea (p<0.05) with the decreasing tendency of CD69 + CD4 + T cells, suggesting that the cell population might be associated with the attenuating effect of cholecalciferol on diarrhea occurrence, although immunoglobulin E levels and cytokine productions were not significantly altered by the treatment of cholecalciferol. When given the mice anti-CD69 mAb treatment, significant improvement of allergic diarrhea symptom was observed (p<0.05), accompanying the decrease of CD69 + CD4 + T cells which suggested the contribution of these cells to the diarrhea symptom. Taken together, we suggest that administration of cholecalciferol might be useful to suppress symptomatic food allergy in association with the decrease of CD69 + CD4 + T cells.

Adoptive cell transfer of an ovalbumin (OVA)-specific T(h)17-polarized cell population from transgenic DO11.10 mice into BALB/c mice followed by OVA inhalation caused airway hyperresponsiveness (AHR) with severe neutrophilia. The transferred T(h)17 cell population-previously polarized in vitro with IL-6, transforming growth factor-beta and IL-23-contained negligible numbers of IFN-gamma-producing cells; however, during T(h)17-cell-dependent airway inflammation, significant numbers of IFN-gamma-producing cells-including cells producing both IL-17 and IFN-gamma and cells producing only IFN-gamma-were detected in the lung in addition to cells producing only IL-17. Using T(h)17-polarized cell populations derived from IL-17(-/-) or IFN-gamma(-/-) mice, it was demonstrated that IL-17 is essential for inducing neutrophilic airway inflammation and that IFN-gamma is required for the AHR elevation. IFN-gamma appeared to be derived from cells producing both IL-17 and IFN-gamma and/or from cells producing only IFN-gamma, which were converted from the transferred T(h)17-polarized cell population. We also found that mAbs that neutralize IL-12 significantly suppressed the conversion of the T(h)17-polarized cell population toward IFN-gamma producers in the lung; concomitantly, with this decreased conversion, IL-12 neutralization also attenuated the AHR elevation in the lung. IL-12-dependent conversion of the transferred T(h)17-polarized cell population into IFN-gamma producers in the lung thus appeared to be a crucial process for inducing AHR elevation in T(h)17-cell-dependent airway inflammation.

3-Methylcholanthrene (MCA)-induced sarcomas have been used as conventional tools for investigating immunosurveillance against tumor development. However, MCA-induced sarcoma is not always an ideal model for the study of the human cancer system because carcinomas and not sarcomas are the dominant types of human cancers. To resolve this problem, we established a novel and simple method to induce mouse squamous cell carcinomas (SCCs). As well known, the subcutaneous injection of MCA caused the formation of sarcomas at 100% incidence. However, we here first succeeded at inducing SCC at 60% of incidence within 2 months by a single intra-dermal injection of MCA. Using this primary SCC model, we demonstrated the critical role of interferon (IFN)-gamma-dependent type 1 immunity in immunosurveillance against SCC from the following results: (i) The incidence of SCC was accelerated in IFN-gamma-deficient mice compared with that in wild-type mice; (ii) In vivo injection of CpG-oligodeoxynucleotides (CpG-ODN) caused a marked reduction in the incidence of SCC in parallel with the activation of type 1-dependent antitumor immunity and (iii) The antitumor activity of CpG-ODN was significantly decreased in IFN-gamma-deficient mice. Thus, our established MCA-induced mouse SCC model could be a powerful tool for evaluating immunosurveillance mechanisms during the development of SCC and might result in a novel strategy to address immunosurveillance mechanisms of human cancer.

Immune balance, which is controlled by IFN-gamma-producing Th1 cells and IL-4-producing Th2 cells, plays a critical role in the regulation of airway inflammation. We have demonstrated that Th1 cells induced neutrophilia, airway hyperresponsiveness (AHR) but not mucus hypersecretion, while Th2 cells induced eosinophilia, AHR and mucus hypersecretion. Here, we indicated that IFN-gamma produced by Th1 cells accelerated neutrophilia and AHR but inhibited eosinophilia and mucus hypersecretion. We also demonstrated an important role of type 1 IFN-alpha/beta during inhibition of Th2-dependent airway inflammation by TLR-9-ligand, CpG-ODN. CpG-ODN-induced IFN-alpha/beta partially appeared to act against Th2 cells to inhibit the production of IL-4 and IL-13, which are key cytokines to regulate the activation and migration of Th2 cells in the lung.

Auranofin, aurothioglucose and aurothiomalate (10 microM each) inhibited 12-O-tetradecanoylphorbol 13-acetate (TPA, 16.2 nM)-induced nuclear translocation of nuclear factor-kappa B (NF-kappaB), and production of nitric oxide (NO) and prostaglandin E(2) (PGE(2)) in rat peritoneal macrophages when the cells were pre-incubated with each gold compound for 20 h. Without pre-incubation for 20 h, aurothioglucose and aurothiomalate, but not auranofin, failed to inhibit the TPA-induced NF-kappaB nuclear translocation and production of NO and PGE(2). Auranofin, aurothioglucose and aurothiomalate did not affect the direct binding of NF-kappaB to the DNA probe. It was suggested that these gold compounds inhibit the TPA-induced production of NO and PGE(2) by inhibiting the NF-kappaB nuclear translocation.