James D. Henderson

Modulation of Airway Inflammation by Immunostimulatory CpG Oligodeoxynucleotides in a Murine Model of Allergic Aspergillosis

ABSTRACT Allergic aspergillosis is a Th2 T-lymphocyte-mediated pulmonary complication in patients with atopic asthma and cystic fibrosis. Therefore, any therapeutic strategy that selectively inhibits Th2 T-cell activation may be useful in downregulating allergic lung inflammation in asthma. In the present study, we developed a CpG oligodeoxynucleotide (ODN)-based immune intervention of allergic inflammation in a mouse model of allergic aspergillosis. Four different groups of mice were used in a short-term immunization protocol. Three experimental groups of animals (groups 1 to 3) were sensitized with Aspergillus fumigatus antigens. Animals in group 1 were immunized with A. fumigatus antigen alone, while those in group 2 were treated with CpG-ODN 1 day before the first antigen immunization, and the animals in group 3 received the first CpG-ODN administration between the antigen treatments. The animals in group 4 served as controls and were given phosphate-buffered saline. Allergen-specific serum immunoglobulins and total immunoglobulin E in different groups of animals were measured by enzyme-linked immunosorbent assay, while airway remodeling and cytokine production were studied by immunohistochemistry. The results demonstrated that CpG-ODN administration either before (group 2) or between (group 3) antigen treatments resulted in reduced total immunoglobulin E levels and peripheral blood eosinophil numbers compared to A. fumigatus allergen-sensitized group 1 animals. Similarly, treatment with CpG-ODN also downregulated inflammatory cell infiltration, goblet cell hyperplasia, and basement membrane thickening compared to A. fumigatus-sensitized mice. The distinct reduction in peripheral blood eosinophilia and airway remodeling in CpG-ODN-treated mice emphasized its usefulness as an immunomodulating agent for allergic fungal diseases.

Alkaline Serine Proteinase from Aspergillus fumigatus Has Synergistic Effects on Asp-f-2-Induced Immune Response in Mice

Background: Exposure to Aspergillus fumigatus allergens results in the sensitization and the development of allergic bronchopulmonary aspergillosis in susceptible individuals. Aspergillus antigen consists of a number of chemically diverse components and their cumulative or synergistic effect may result in disease. When mice were challenged with individual recombinant allergens, there was only reduced inflammation and immunological responses compared to the whole antigen. Various enzymes identified from A. fumigatus have been thought to cause airway damage. In the present study, we evaluated the effect of exposure to Asp f 13, an alkaline serine proteinase, and Asp f 2 in mice. Methods: BALB/c mice were challenged intranasally with Asp f 2 and Asp f 13 alone and in combination. The antibody response, pulmonary inflammation, and airway hyperreactivity were studied. Results: Results demonstrated no major difference in antibody response and airway responses among the different groups. The inflammatory responses in the lungs, however, showed marked differences in the various groups. Conclusion: In spite of the similar immunological responses in the different groups of mice studied, the results demonstrate enhanced inflammation in the lungs of mice exposed to a combination of both allergens. Allergens with proteinase activity have been found to be involved in airway inflammation and remodeling, which may also apply for Aspergillus-induced allergy.

The yjeQ Gene Is Required for Virulence of Staphylococcus aureus

ABSTRACT Gene products required for in vivo growth and survival of Staphylococcus aureus and other pathogens represent new targets for antimicrobial chemotherapy. In this study we created a Staphylococcus aureus yjeQ deletion strain and tested its virulence using a mouse kidney abscess infection model. The yjeQ deletion strain was compromised for growth in vitro and severely attenuated for virulence. We concluded that yjeQ is an attractive and novel new drug target.

The costimulatory molecules CD80, CD86 and OX40l are up-regulated in Aspergillus fumigatus sensitized mice

Aspergillus fumigatus (Af) is a fungus associated with allergic bronchopulmonary aspergillosis (ABPA) and other allergic diseases. Immune responses in these diseases are due to T and B cell responses. T cell activation requires both Af‐specific engagement of the T‐cell‐receptor as well as interaction of antigen independent costimulatory molecules including CD28‐CD80/CD86 and OX40–OX40L interactions. Since these molecules and their interactions have been suggested to have a potential involvement in the pathogenesis of ABPA, we have investigated their role in a model of experimental allergic aspergillosis. BALB/c mice were primed and sensitized with Af allergens, with or without exogenous IL‐4. Results showed up‐regulation of both CD86 and CD80 molecules on lung B cells from Af‐sensitized mice (79% CD86+ and 24% CD80+) and Af/rIL‐4‐treated mice (90% CD86+ and 24% CD80+) compared to normal controls (36% and 17%, respectively). Lung macrophages in Af‐sensitized mice treated or not with IL‐4 showed enhanced expression of these molecules. OX40L expression was also up‐regulated on lung B cells and macrophages from both Af‐sensitized and Af/rIL‐4 exposed mice as compared to normal controls. All Af‐sensitized animals showed peripheral blood eosinophilia, enhanced total serum IgE and allergen‐specific IgG1 antibodies and characteristic lung inflammation. The up‐regulation of CD80, CD86 and OX40L molecules on lung B cells and macrophages from Af‐allergen exposed mice suggests a major role for these molecules in the amplification and persistence of immunological and inflammatory responses in ABPA.

Spatial distribution and temporal onset of NF-kB activation and inducible nitric oxide synthase within pancreatic islets in the pre-diabetic stage of genetic, diabetic-prone BB rats: Attenuation by drug intervention decreases inflammatory cell infiltration and incidence of diabetes

AbstractObjective and Design: To document in vivo immunolocalization and activation of nuclear factor-κB (NF-κB) and inducible nitric oxide synthase (iNOS) expression in prediabetic stages of diabetes mellitus. Material or Subjects: Genetic, diabetic-prone or diabetic-resistant BB rats (total = 189). Treatment: Various doses of an oral dithiocarbamate derivative, NOX-700, or cyclosporine (2.5 mg/kg) starting at 30 or 60 days of age. Methods: Immunohistochemistry, electrophoretic mobility shift assays, plasma glucose. Results: NF-κB and iNOS was increased in pancreas of hyperglycemic, diabetic-prone rats but not normoglycemic, diabetic-resistant rats. Immunostaining for NF-κB and iNOS was largely confined to islets and occurred in diabetic-prone rats prior to overt hyperglycemia. NOX-700 decreased cell infiltration, delayed the onset of disease and decreased the incidence of hyperglycemia to levels achieved by immunosuppressant therapy. NOX-700 also decreased the intensity of immunoreactive NF-κB and iNOS within pancreatic islets. Conclusions: These studies support a role of NF-kB and iNOS in diabetogenesis in vivo.

A dithiocarbamate analogue decreases intraislet cell infiltration and the incidence of diabetes mellitus in the genetic diabetes-prone BB rat.

Dithiocarbamates are a class of agents that have interesting biologic properties including the ability to limit the production and/or action of nitric oxide (NO). These agents are also potential immunosuppressant agents. Since immunosuppressant agents have been examined for remission of disease in clinical trials, we wanted to examine whether a dithiocarbamate analogue, NOX-200, might inhibit diabetogenesis in the genetic diabetes-prone BB rat model. Immunohistochemical analysis revealed inducible NO synthase (iNOS) gene expression in pancreatic islets of both normoglycemic and hyperglycemic diabetes-prone BB rats but not in diabetes-prone BB rats at the early age of 30 days or in diabetes-resistant BB rats. A qualitative decrease in immunostaining for iNOS was also observed in the pancreata of drug-treated animals. Long-term treatment with NOX-200, used alone or in combination with low-dose cyclosporine (CsA), significantly reduced the incidence of diabetes mellitus. In the subset of animals that became diabetic, NOX-200 did not alter either the time to onset of hyperglycemia or the level of hyperglycemia, insulinopenia, or lymphocytic cell infiltration into the pancreas. In contrast, in animals that did not develop hyperglycemia, treatment with NOX-200 decreased inflammatory cell infiltration into the pancreas equipotent to that seen using CsA. These studies demonstrate the potential therapeutic efficacy of dithiocarbamates to oppose the development of autoimmune insulin-dependent diabetes mellitus by limiting inflammatory cell activation/infiltration.