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Main conclusion: Verticillium colonization does induce a cascade of defense/stress proteins but the Ve1 gene also promotes enhanced root growth, which appears to allow the plant to outgrow the pathogen and avoid symptoms associated with an exaggerated defense response.In tomato, the Ve1 gene provides resistance to the vascular pathogen, Verticillium dahliae, race 1; ve1 plants are susceptible. However, the physiological basis of the resistance is unknown. While developing alternative lines of mutant Ve1 gene transformants to address this question a striking difference was observed in transformation frequency resulting from the inefficient rooting of plantlets from ve1 callus relative to Ve1 callus. Subsequent experiments with resistant and susceptible near-isolines of the cultivar Craigella, as well as Ve1 transformants, showed that in both artificial medium and soil, root growth was significantly enhanced in the resistant cultivar. Parallel studies of Verticillium colonization indicated a significantly lower overall concentration in the resistant plant characteristic of the resistant phenotype, but an almost equal total fungal biomass in both resistant and susceptible roots. Proteomic analyses of the roots of Verticillium-infected plants revealed elevated levels of defense/stress proteins, which correlated with the fungal concentration rather than resistance. Hormone analyses demonstrated a higher cis-ABA level in the resistant isoline consistent with enhanced root growth. Taken together these studies indicate a similar fungal biomass in the roots of both isolines where the Ve1 gene also promotes root production. In the case of the Craigella/Vd1 pathosystem, this appears to allow the host to resist better by outgrowing the pathogen with less wilt rather than reliance only on partial immunity. [ABSTRACT FROM AUTHOR]

Background Aims: Esophageal eosinophilia (EE) can be caused by gastroesophageal reflux disease (GERD), protonpump inhibitor-responsive EE (PPI-REE) or eosinophilic esophagitis (EoE). This study quantified protein expression and S-nitrosylation (SNO) post-translational modifications in EE to elucidate potential disease biomarkers. Methods: Proximal and distal esophageal (DE) biopsy proteins in patients with EE and in controls were assayed for protein content and fluorescence-labeled with and without ascorbate treatment. Protein SNO was determined, and selected protein spots were identified by matrix-assisted laser desorption ionization time-of-flight/mass spectrometry. Western blot and ingenuity pathway analysis were performed. Results: Ninetyone of 648 proteins showed differential expression. There were significantly altered levels of abundance for 11 proximal and 14 DE proteins. Hierarchal clustering revealed differential SNO in inflamed tissues, indicating reactive nitrogen/ oxygen species involvement. Galectin-3 was upregulated in both proximal (p < 0.04) and distal (p < 0.004) esophageal EE biopsies compared to controls. In distal EE samples, galectin-3 was significantly S-nitrosylated (p < 0.004). Principal component analysis revealed sample group discrimination distally. Conclusion: Proteomic analysis in EE esophageal mucosa revealed a distinct abundance and nitrosylation profile, most prominently in distal biopsies. Galectin- 3 was upregulated in expression and SNO, which may indicate its potential role in mucosal inflammation. These results call for more studies to be performed to investigate the role of galectin-3 in GERD, PPI-REE and EoE. [ABSTRACT FROM AUTHOR]

We sought to identify cells and cytokines in bronchoalveolar lavage (BAL) fluids that distinguish asthma from healthy control subjects and those that distinguish controlled asthma from uncontrolled asthma. Following informed consent, 36 human subjects were recruited for this study. These included 11 healthy control subjects, 15 subjects with controlled asthma with FEV1≥80% predicted and 10 subjects with uncontrolled asthma with FEV1 <80% predicted. BAL fluid was obtained from all subjects. The numbers of different cell types and the levels of 48 cytokines were measured in these fluids. Compared to healthy control subjects, patients with asthma had significantly more percentages of eosinophils and neutrophils, IL-1RA, IL-1α, IL-1β, IL-2Rα, IL-5, IL-6, IL-7, IL-8, G-CSF, GROα (CXCL1), MIP-1β (CCL4), MIG (CXCL9), RANTES (CCL5) and TRAIL in their BAL fluids. The only inflammatory markers that distinguished controlled asthma from uncontrolled asthma were neutrophil percentage and IL-8 levels, and both were inversely correlated with FEV1. We examined whether grouping asthma subjects on the basis of BAL eosinophil % or neutrophil % could identify specific cytokine profiles. The only differences between neutrophil-normal asthma (neutrophil≤2.4%) and neutrophil-high asthma (neutrophils%>2.4%) were a higher BAL fluid IL-8 levels, and a lower FEV1 in the latter group. By contrast, compared to eosinophil-normal asthma (eosinophils≤0.3%), eosinophil-high asthma (eosinophils>0.3%) had higher levels of IL-5, IL-13, IL-16, and PDGF-bb, but same neutrophil percentage, IL-8, and FEV1. Our results identify neutrophils and IL-8 are the only inflammatory components in BAL fluids that distinguish controlled asthma from uncontrolled asthma, and both correlate inversely with FEV1. [ABSTRACT FROM AUTHOR]

Background: A series of epidemiologic studies have identified the fungus Alternaria as a major risk factor for asthma. The airway epithelium plays a critical role in the pathogenesis of allergic asthma. These reports suggest that activated airway epithelial cells can produce cytokines such as IL-25, TSLP and IL-33 that induce Th2 phenotype. However the epitheliumderived products that mediate the pro-asthma effects of Alternaria are not well characterized. We hypothesized that exposure of the airway epithelium to Alternaria releasing cytokines that can induce Th2 differentiation. Methodology/Principal Finding: We used ELISA to measure human and mouse cytokines. Alternaria extract (ALT-E) induced rapid release of IL-18, but not IL-4, IL-9, IL-13, IL-25, IL-33, or TSLP from cultured normal human bronchial epithelial cells; and in the BAL fluids of naïve mice after challenge with ALT-E. Both microscopic and FACS indicated that this release was associated with necrosis of epithelial cells. ALT-E induced much greater IL-18 release compared to 19 major outdoor allergens. Culture of naïve CD4 cells with rmIL-18 induced Th2 differentiation in the absence of IL-4 and STAT6, and this effect was abrogated by disrupting NF- kκ p50 or with a NEMO binding peptide inhibitor. Conclusion/Significance: Rapid and specific release of IL-18 from Alternaria-exposed damaged airway epithelial cells can directly initiate Th2 differentiation of naïve CD4+ T-cells via a unique NF-κB dependent pathway. [ABSTRACT FROM AUTHOR]

Allergic asthma is characterized by airway eosinophilia, increased mucin production and allergen-specific IgE. Fc gamma receptor IIb (FcγRIIb), an inhibitory IgG receptor, has recently emerged as a negative regulator of allergic diseases like anaphylaxis and allergic rhinitis. However, no studies to date have evaluated its role in allergic asthma. Our main objective was to study the role of FcγRIIb in allergic lung inflammation. We used a murine model of allergic airway inflammation. Inflammation was quantified by BAL inflammatory cells and airway mucin production. FcγRIIb expression was measured by qPCR and flow cytometry and the cytokines were quantified by ELISA. Compared to wild type animals, FcγRIIb deficient mice mount a vigorous allergic lung inflammation characterized by increased bronchoalveolar lavage fluid cellularity, eosinophilia and mucin content upon ragweed extract (RWE) challenge. RWE challenge in sensitized mice upregulated FcγRIIb in the lungs. Disruption of IFN-γ gene abrogated this upregulation. Treatment of naïve mice with the Th1-inducing agent CpG DNA increased FcγRIIb expression in the lungs. Furthermore, treatment of sensitized mice with CpG DNA prior to RWE challenge induced greater upregulation of FcγRIIb than RWE challenge alone. These observations indicated that RWE challenge upregulated FcγRIIb in the lungs by IFN-γ- and Th1-dependent mechanisms. RWE challenge upregulated FcγRIIb on pulmonary CD14+/MHC II+ mononuclear cells and CD11c+ cells. FcγRIIb deficient mice also exhibited an exaggerated RWE-specific IgE response upon sensitization when compared to wild type mice. We propose that FcγRIIb physiologically regulates allergic airway inflammation by two mechanisms: 1) allergen challenge mediates upregulation of FcγRIIb on pulmonary CD14+/MHC II+ mononuclear cells and CD11c+ cells by an IFN-γ dependent mechanism; and 2) by attenuating the allergen specific IgE response during sensitization. Thus, stimulating FcγRIIb may be a therapeutic strategy in allergic airway disorders. [ABSTRACT FROM AUTHOR]

The atrial gland is an exocrine organ that secretes into the oviduct of Aplysia californica and expresses three homologous genes belonging to the egglaying hormone gene family. Although post-translational processing of the egg-laying hormone precursor in the neuroendocrine bag cells has been examined in detail, relatively little is known about the post-translational processing of egg-laying hormone-related gene products in the atrial gland. A combination of morphologic techniques that included light-microscopic histology and immunocytochemistry, transmission electron microscopy, and immuno-electron microscopy were used to localize egg-laying hormone-related peptides in the atrial gland and to evaluate the characteristic morphology of their secretory cells. Results of these studies showed that there were at least three major types of secretory cells in the atrial gland (types 1-3). Significantly, of these three cell types, only type 1 was immunoreactive to antisera against egg-laying hormone-related precursor peptides. The immunoreactivity studies established that all three egg-laying hormone-related precursor genes are expressed in type-1 cells and indicated that the processing of these precursors also occurs within the secretory granules of this cell type. Evidence was also obtained that proteolytic processing of the egg-laying hormone-related precursors differed significantly from that observed in the bag cells. In contrast to the bag cells, the NH-terminal and COOH-terminal products of the egg-laying hormone-related precursors of the atrial gland were not sorted into different types of vesicles. [ABSTRACT FROM AUTHOR]

We have screened an Aplysia atrial gland cDNA library using an egg-laying hormone (ELH) precursor probe and have isolated and characterized five different clones, four of which are full-length and approximately 0.8 kb in size. The characterization of these cDNA clones firmly established the genetic variation of the ELH-related precursors expressed in the atrial gland and provided a rational basis for their revised nomenclature proposed herein. The five precursor ELH-related cDNA sequences obtained predicted the following genetically distinct polypeptide precursors designated as: A, [Asp143]A, [Glu94,Gln139]A, [Pro25]B, and [Phe96,Asp107] Bt. The [Phe96,Asp107] Bt cDNA sequence predicted a truncated form of a B-type precursor. Northern blot analysis of atrial gland RN A identified two transcripts of about equal intensity of 0.9 kb and 1.1kb. Polymerase chain reaction of genomic DNA, together with DNA sequence analysis, resolved previously reported discrepancies between genomic and cDNA sequences of the ELH-related precursors. Taken together the results obtained identified the expression of five ELH-related precursor genes in the atrial gland of Aplysia from at least two genetic loci per haploid genome. [ABSTRACT FROM AUTHOR]