Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0032285 (pneumonia)
54,520 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We investigated keratinocyte growth factor (KGF) as a pretreatment therapy for idiopathic pneumonia syndrome (IPS) generated as a result of lung damage and allogeneic T cell-dependent inflammatory events occurring in the early peri-bone marrow (BM) transplant (BMT) period. B10.BR (H2(k)) recipient mice were transplanted with C57BL/6 (H2(b)) BM with spleen cells after lethal irradiation with and without cyclophosphamide conditioning with and without subcutaneous KGF pretreatment. KGF-pretreated mice had fewer injured alveolar type II (ATII) cells at the time of BMT and exhibited ATII cell hyperplasia at day 3 post-BMT. The composition of infiltrating cells on day 7 post-BMT was not altered by KGF pretreatment, but the frequencies of cells expressing the T-cell costimulatory molecules B7.1 and B7.2 and mRNA for the cytolysin granzyme B (usually increased in IPS) were decreased by KGF. Sera from KGF-treated mice had increases in the Th2 cytokines interleukin (IL)-4, IL-6, and IL-13 4 days after cessation of KGF administration (i.e., at the time of BMT). These data suggest that KGF hinders IPS by two modes: 1) stimulation of alveolar epithelialization and 2) attenuation of immune-mediated injury as a consequence of failure to upregulate cytolytic molecules and B7 ligand expression and the induction of anti-inflammatory Th2 cytokines in situ.
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PMID:KGF pretreatment decreases B7 and granzyme B expression and hastens repair in lungs of mice after allogeneic BMT. 1078 30

While much progress has been achieved in controlling infectious diseases, there is a startling increase in the prevalence of allergic disorders in developed countries. Previous studies using experimental murine models of asthma have demonstrated that mycobacterial infections are capable of suppressing asthma-like reactions induced by ovalbumin (OVA). Using a different intracellular bacterium, Chlamydia trachomatis mouse pneumonitis (MoPn), we examined the effect of infection on the development of allergic responses to a common natural airborne allergen, ragweed (RW). The data showed that airway eosinophilia induced by ragweed sensitization/challenge was significantly reduced in MoPn-infected mice. MoPn-infected mice also exhibited significantly lower levels of allergen-driven Th2 cytokine production, namely IL-4, IL-5, IL-10, and IL-13, following ragweed exposure in comparison with those treated with ragweed only. Additionally, the production of eotaxin, a C-C chemokine for eosinophil chemoattraction following RW exposure, was significantly reduced in the lungs of MoPn-infected mice. However, MoPn infection did not reduce the levels of RW-specific IgE and IgG1 production in the sera, nor did it diminish the level of total serum IgE. These data provide evidence that the suppression of the allergic airway inflammation induced by a common environmental allergen is attainable through intracellular bacterial infection.
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PMID:Chlamydia trachomatis infection inhibits airway eosinophilic inflammation induced by ragweed. 1178 Oct 65

Thymus- and activation-regulated chemokine (TARC/CCL17) is a lymphocyte-directed CC chemokine, which plays a role in the recruitment of CC chemokine receptor-4 positive T helper 2 (Th2) cells. In this study, we measured concentrations of TARC and Th2 cell-derived cytokines in bronchoalveolar lavage (BAL) fluid, as well as TARC concentrations in serum from patients with eosinophilic pneumonia and other interstitial lung diseases. TARC was significantly elevated in BAL fluids from patients with eosinophilic pneumonia (median, 240 pg/ml), whereas TARC was undetectable (< 7 pg/ml) in most cases of hypersensitivity pneumonitis, sarcoidosis, and idiopathic pulmonary fibrosis, as well as in healthy control subjects. Also, when present, quantities were less than 20 pg/ml. Elevated concentrations of interleukin (IL)-4, IL-5, and IL-13 were also detected in BAL fluid from patients with eosinophilic pneumonia. Interestingly, TARC concentrations in BAL fluids were closely correlated with the concentrations of IL-5 and IL-13. A serial examination showed that elevated TARC in BAL fluid rapidly fell to below detectable limits preceding decreases in IL-5 concentration and eosinophil percentage. Our results, in concordance with previous studies, demonstrate the potential activity of TARC for recruiting Th2 cells to the lungs and suggest a significant role for TARC in the pathogenesis of eosinophilic pneumonia.
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PMID:Elevated levels of thymus- and activation-regulated chemokine in bronchoalveolar lavage fluid from patients with eosinophilic pneumonia. 1195 56

An IgE-dependent histamine-releasing factor (HRF p23; also known as translationally controlled tumor protein or p23) stimulates the release of histamine, IL-4, and IL-13 from a subpopulation of highly allergic donor basophils. It has also been shown to act as a chemoattractant for eosinophils. To elucidate novel functions of HRF p23 in airway inflammation, we examined the effects of human recombinant HRF p23 (hrHRF) on bronchial epithelium and found that hrHRF stimulated the secretions of IL-8 and granulocyte/macrophage colony-stimulating factor by both primary cultures of human bronchial epithelial cells and BEAS-2B cells. In response to hrHRF, these cells induced IL-8 mRNA expression within 4 h. H2O2, but not IL-1 beta or tumor necrosis factor-alpha, stimulated secretion of HRF p23 by BEAS-2B cells, suggesting that oxidative stress may trigger the release of HRF p23 from bronchial epithelial cells. Bronchoalveolar lavage (BAL) from healthy volunteers contained only trivial or undetectable amounts of HRF p23. Significantly higher amounts of HRF p23 were recovered from BAL fluid taken from asthmatic patients, and the amounts of HRF p23 were further elevated in patients with idiopathic eosinophilic pneumonia. Our results demonstrate for the first time that HRF p23 can stimulate nonimmune epithelium. HRF p23 derived from bronchial epithelial cells may regulate complex cytokine networks in eosinophil-dependent inflammation of the human airway.
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PMID:Stimulation of human bronchial epithelial cells by IgE-dependent histamine-releasing factor. 1294 34

Although Cryptococcus neoformans is recognized for its ability to cause meningoencephalitis and pneumonia among immunocompromised persons, subclinical pulmonary infection is also common among immunocompetent persons. The significance of this infection is unknown. Using a rat model, we explored the potential for pulmonary cryptococcosis to modify allergic responses and airway reactivity. Our findings indicate that localized pulmonary cryptococcal infection (but not disseminated infection) can exacerbate allergic responses to respiratory challenge with ovalbumin, as measured by total immunoglobulin E levels, ovalbumin-specific immunoglobulin E titers, and eosinophil content of bronchoalveolar lavage fluid. Infection-associated enhancement of allergic responses was not dependent on cryptococcal encapsulation and was partially ameliorated by the administration of fluconazole. Increases in both the number of goblet cells and airway responsiveness, which are also features of reactive airway disease, were also present with pulmonary infection. An examination of lung cytokine levels in the context of active pulmonary infection revealed increased expression of interleukin (IL)-10, tumor necrosis factor- alpha , and IL-13, but not IL-12 or interferon- gamma . In contrast, systemic infection was associated with higher levels of interferon- gamma but lower levels of IL-13. Our studies highlight the potential for localized pulmonary C. neoformans infection to potentiate allergic responses and airway reactivity and suggest a potential role for subclinical pulmonary cryptococcosis in the pathogenesis of asthma.
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PMID:Enhanced allergic inflammation and airway responsiveness in rats with chronic Cryptococcus neoformans infection: potential role for fungal pulmonary infection in the pathogenesis of asthma. 1654 60

Chlamydial infections are serious public health concerns worldwide. In this study, we examined the role of dendritic cell (DC) subsets in inducing protective immunity against chlamydial infection using an adoptive transfer approach. We found that CD11c+CD8alpha+ (double-positive, DP) DC, compared with CD11c+CD8alpha- (single-positive, SP) DC isolated from infected mice, are more potent inducers of protective immunity. Specifically, mice pretreated with DPDC from infected mice, upon infection with Chlamydia trachomatis mouse pneumonitis (MoPn), experienced significantly less severe body weight loss and in vivo chlamydial growth. Analysis of MoPn-driven cytokine production by immune cells revealed that mice that were treated with DPDC produced significantly higher levels of Th1 (TNF-alpha, IFN-gamma, and IL-12) but lower levels of Th2 (IL-4, IL-5, and IL-13)-related cytokines than the recipients of SPDC following infection challenge. Moreover, DPDC-treated mice displayed significantly higher levels of MoPn-specific IgG2a production and delayed-type hypersensitivity responses compared with SPDC-treated mice. Furthermore, DPDC isolated from infected mice produced higher amounts of IL-12 and IL-10 in vitro in comparison with SPDC. These data indicate that CD8alpha+ DC have a significantly higher capacity in inducing protective immunity compared with CD8alpha- DC, demonstrating the crucial role of DC1-like cells in eliciting protection against C. trachomatis infection.
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PMID:Adoptive transfer of CD8alpha+ dendritic cells (DC) isolated from mice infected with Chlamydia muridarum are more potent in inducing protective immunity than CD8alpha- DC. 1708 23

Lymphopenia and restricted T cell repertoires in humans are often associated with severe eosinophilic disease and a T cell Th2 bias. To examine the pathogenesis of this phenomenon, C57BL/6 Rag2-/- mice received limited (3 x 10(4)) or large (2 x 10(6)) numbers of CD4 T cells. Three to 5 months after transfer, mice that had received 3 x 10(4) T cells, but not those that received 2 x 10(6), developed fulminant macrophage pneumonia with eosinophilia, Ym1 deposition, and methacholine-induced airway hyperresponsiveness, as well as eosinophilic gastritis; esophagitis and other organ damage occurred in some cases. Donor cells were enriched for IL-4, IL-5, and IL-13 producers. When 3 x 10(4) cells were transferred into CD3epsilon-/- hosts, the mice developed strikingly elevated serum IgE. Prior transfer of 3 x 10(5) CD25+ CD4 T cells into Rag2-/- recipients prevented disease upon subsequent transfer of CD25- CD4 T cells, whereas 3 x 10(4) regulatory T cells (Tregs) did not, despite the fact that there were equal total numbers of Tregs in the host at the time of transfer of CD25- CD4 T cells. Limited repertoire complexity of Tregs may lead to a failure to control induction of immunopathologic responses, and limitation in repertoire complexity of conventional cells may be responsible for the Th2 phenotype.
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PMID:Lymphopenic mice reconstituted with limited repertoire T cells develop severe, multiorgan, Th2-associated inflammatory disease. 1720 52

In humans, limited T-cell receptor repertoire and lymphopenia are associated with severe eosinophilic inflammatory disease. A model of lymphopenia and reduced T-cell repertoire was created; C57BL/6 Rag2-/- mice received limited (30,000) or large (2 million) numbers of CD4 T-cells. Three to five months post-transfer, mice that had received 30,000 T-cells, but not those that received 2 million, developed fulminant macrophage pneumonia with eosinophilia, Ym1 deposition. methacholine-induced airway hyperresponsiveness, eosinophilic gastritis and esophagitis. These mice had strikingly elevated serum IgE (in CD3epsilon-/- hosts) and donor-cells were enriched for IL-4, IL-5 and IL-13 producers. Th2 pathology and serum IgE were enhanced when transferred populations were depleted of CD25+ CD4 Tregs, but was more severe when the effector population was derived from limited as compared to the large effector population. Pretreatment of Rag2-/- mice with 300,000 CD25+ CD4 Tregs prior to effector cell transfer prevented disease while pretreatment with 30,000 did not, despite the fact that there were equal numbers of Tregs in the hosts at the time of transfer of effector cells. Limited repertoire complexity of Tregs may lead to a failure to control immunopathologic responses and limited repertoire complexity of conventional cells may be responsible for the Th2 phenotype.
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PMID:Repertoire-dependent immunopathology. 1788 7

The antiviral activities of type I IFNs have long been established. However, comparatively little is known of their role in defenses against nonviral pathogens. We examined here the effects of type I IFNs on host resistance against the model pathogenic yeast Cryptococcus neoformans. After intratracheal or i.v. challenge with this fungus, most mice lacking either the IFN-alpha/beta receptor (IFN-alpha/betaR) or IFN-beta died from unrestrained pneumonia and encephalitis, while all wild-type controls survived. The pulmonary immune response of IFN-alpha/betaR-/- mice was characterized by increased expression of IL-4, IL-13, and IL-10, decreased expression of TNF-alpha, IFN-gamma, inducible NO synthetase, and CXCL10, and similar levels of IL-12 mRNA, compared with wild-type controls. Histopathological analysis showed eosinophilic infiltrates in the lungs of IFN-alpha/betaR-/- mice, although this change was less extensive than that observed in similarly infected IFN-gammaR-deficient animals. Type I IFN responses could not be detected in the lung after intratracheal challenge. However, small, but statistically significant, elevations in IFN-beta levels were measured in the supernatants of bone marrow-derived macrophages or dendritic cells infected with C. neoformans. Our data demonstrate that type I IFN signaling is required for polarization of cytokine responses toward a protective type I pattern during cryptococcal infection.
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PMID:IFN-alpha/beta signaling is required for polarization of cytokine responses toward a protective type 1 pattern during experimental cryptococcosis. 1856 23

Enhanced disease is the term used to describe the aberrant Th2-skewed responses to naturally acquired human respiratory syncytial virus (hRSV) infection observed in individuals vaccinated with formalin-inactivated viral Ags. Here we explore this paradigm with pneumonia virus of mice (PVM), a pathogen that faithfully reproduces features of severe hRSV infection in a rodent host. We demonstrate that PVM infection in mice vaccinated with formalin-inactivated Ags from PVM-infected cells (PVM Ags) yields Th2-skewed hypersensitivity, analogous to that observed in response to hRSV. Specifically, we detect elevated levels of IL-4, IL-5, IL-13, and eosinophils in bronchoalveolar lavage fluid of PVM-infected mice that were vaccinated with PVM Ags, but not among mice vaccinated with formalin-inactivated Ags from uninfected cells (control Ags). Interestingly, infection in PVM Ag-vaccinated mice was associated with a approximately 10-fold reduction in lung virus titer and protection against weight loss when compared with infected mice vaccinated with control Ags, despite the absence of serum-neutralizing Abs. Given recent findings documenting a role for eosinophils in promoting clearance of hRSV in vivo, we explored the role of eosinophils in altering the pathogenesis of disease with eosinophil-deficient mice. We found that eosinophil deficiency had no impact on virus titer in PVM Ag-vaccinated mice, nor on weight loss or levels of CCL11 (eotaxin-1), IFN-gamma, IL-5, or IL-13 in bronchoalveolar lavage fluid. However, levels of both IL-4 and CCL3 (macrophage inflammatory protein-1alpha) in bronchoalveolar lavage fluid were markedly diminished in PVM Ag-vaccinated, PVM-infected eosinophil-deficient mice when compared with wild-type controls.
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PMID:Pulmonary eosinophils and their role in immunopathologic responses to formalin-inactivated pneumonia virus of mice. 1954 71


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