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Granulocyte Infiltration (granulocyte + infiltration)

Distribution by Scientific Domains

Medical Sciences	75%

Selected Abstracts

Molecular and histological responses in rat skin exposed to m -xylene,

JOURNAL OF BIOCHEMICAL AND MOLECULAR TOXICOLOGY, Issue 2 2003
Palur G. Gunasekar
Abstract Solvents, surfactants, cutting fluids, hydrocarbons, and oils cause skin irritation by incompletely understood mechanisms. This study examined histological and molecular changes in rodent skin caused by brief topical exposures to m -xylene. At 0, 1, 2, 4, and 6 h after 1-h exposure, skin samples were removed and analyzed for histopathological changes and interleukin-1, (IL-1,) and inducible nitric oxide synthase (iNOS) protein levels. Histopathological changes (epidermal,dermal separation and granulocyte infiltration) and increases in IL-1, and iNOS protein expression occurred during our observation period. IL-1, levels increased by 80% immediately after exposure and iNOS levels increased about 60% 4 hours after exposure. Our study demonstrates that dermal exposure to m -xylene promotes IL-1, and iNOS production in skin and these proteins may serve as early indicators of skin irritation. © 2003 Wiley Periodicals, Inc. J Biochem Mol Toxicol 17:92,94, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/jbt.10065 [source]

Evaluation of the immune response against Strongyloides venezuelensis in antigen-immunized or previously infected mice

PARASITE IMMUNOLOGY, Issue 3 2008
A. FERNANDES
Summary The present study was carried out to investigate the immune response against Strongyloides venezuelensis infection in Balb/c mice previously immunized with larva-antigens or primed with live-larvae. Our results indicate that all primed mice developed a strong protection against challenge infection that remained active for 45 days. In mice primed with live-larvae the challenge infection resulted in great reduction of migrating larvae and the worms were completely eliminated from the small intestine before maturation. The protection pattern did not alter when the primary infection was aborted by drug treatment. In these experimental groups, the challenge infection was accompanied by a type-2 predominant immune response, intense IgE and reactive IgG1 production, and granulocyte infiltration in skin, lungs and intestine. The challenge infection in antigen-immunized mice also resulted in great reduction of migrating larvae. However, the worms that reached the host intestine matured, produced eggs and were eliminated similarly to the ones from nonimmunized mice. Protective mechanisms after immunization with larva antigen were migrating larva-specific and associated with a strong and mixed Th1 and Th2 response, without tissue granulocyte infiltration. In conclusion, protective immunity induced by a previous infection or antigen-immunization are stage-specific and operate through different effector mechanisms. [source]

Cellular and molecular mechanisms in chronic obstructive pulmonary disease: an overview

CLINICAL & EXPERIMENTAL ALLERGY, Issue 8 2004
A. Di Stefano
Summary In the last decade, the analysis of bronchial biopsies and lung parenchyma obtained from chronic obstructive pulmonary disease (COPD) patients compared with those from smokers with normal lung function and non-smokers has provided new insights on the role of the different inflammatory and structural cells, their signalling pathways and mediators, contributing to a better knowledge of the pathogenesis of COPD. This review summarizes and discusses the lung pathology of COPD patients with emphasis on inflammatory cell phenotypes that predominate in different clinical conditions. In bronchial biopsies, a cascade of events takes place during progression from mild-to-severe disease. T lymphocytes, particularly CD8+ cells and macrophages are the prevalent inflammatory cells in the lung of healthy smokers and patients with mild COPD, while total and activated neutrophils predominate in severe COPD. The number of CD4+, CD8+ cells and macrophages expressing nuclear factor-kappa B (NF-,B), STAT-4 and IFN-, proteins as well as endothelial adhesion molecule-1 in endothelium is increased in mild/moderate disease. In contrast, activated neutrophils (MPO+ cells) and increased nitrotyrosine immunoreactivity develops in severe COPD. In bronchial biopsies obtained during COPD exacerbations, some studies have shown an increased T cell and granulocyte infiltration. Regular treatment with high doses of inhaled glucocorticoids does not significantly change the number of inflammatory cells in bronchial biopsies from patients with moderate COPD. The profile in lung parenchyma is similar to bronchial biopsies. ,Healthy' smokers and mild/moderate diseased patients show increased T lymphocyte infiltration in the peripheral airways. Pulmonary emphysema is associated with a general increase of inflammatory cells in the alveolar septa. The molecular mechanisms driving the lymphocyte and neutrophilic prevalence in mild and severe disease, respectively, needs to be extensively studied. Up-regulation of pro-inflammatory transcription factors NF-,B and STAT-4 in mild, activated epithelial and endothelial cells in the more severe disease may contribute to this differential prevalence of infiltrating cells. [source]