Airway contraction and cytokine release in isolated rat lungs induced by wear particles from the road and tire interface and road vehicle brakes.

The dominant road traffic particle sources are wear particles from the road and tire interface, and from vehicle brake pads. The aim of this work was to investigate the effect of road and brake wear particles on pulmonary function and biomarkers in isolated perfused rat lungs. Particles were sampled from the studded tire wear of three road pavements containing different rock materials in a road simulator; and from the wear of two brake pad materials using a pin-on-disk machine.

Wear particles generated from studded tires and pavement induces inflammatory reactions in mouse macrophage cells.

Health risks associated with exposure to airborne particulate matter (PM) have been shown epidemiologically as well as experimentally, pointing to both respiratory and cardiovascular effects. These health risks are of increasing concern in society, and to protect public health, a clarification of the toxic properties of particles from different sources is of importance. Lately, wear particles generated from traffic have been recognized as a major contributing source to the overall particle load, especially in the Nordic countries where studded tires are used.

Interferon gamma-induced gene expression of the novel secretory phospholipase A2 type IID in human monocyte-derived macrophages is inhibited by lipopolysaccharide.

Phospholipase A(2) (PLA(2)) is a superfamily of enzymes that may play a major role in airways inflammation. We investigated the effect of interferon-gamma (IFN-gamma) on the gene expression of 19 different PLA(2) types in human monocyte-derived macrophages and nasal epithelial cells (RPMI 2650). The cells were stimulated with IFN-gamma for different lengths of time (up to 48 h), and the mRNA levels of the different PLA(2) types were determined by reverse transcriptase-PCR (RT-PCR) and normalized to those of the house-keeping gene, GAPDH.

Comparison of genotoxic and inflammatory effects of particles generated by wood combustion, a road simulator and collected from street and subway.

The health effects of exposure to airborne particles are of increasing concern in society. In order to protect public health, a clarification of the toxic properties of particles from different sources is of importance. The aim of this study was to investigate and compare the genotoxicity and the ability to induce inflammatory mediators of nine different particle types from wood and pellets combustion, from tire-road wear and collected from an urban street and a subway station.

Exposure to wear particles generated from studded tires and pavement induces inflammatory cytokine release from human macrophages.

Health risks associated with exposure to airborne particulate matter (PM) have been shown epidemiologically as well as experimentally, pointing to both respiratory and cardiovascular effects. Lately, wear particles generated from traffic have been recognized to be a major contributing source to the overall particle load, especially in the Nordic countries were studded tires are used. In this work, we investigated the inflammatory effect of PM10 generated from the wear of studded tires on two different types of pavement.

Phospholipase A2 mRNA expression in the nasal mucosa of healthy subjects and patients with seasonal allergic rhinitis.

Phospholipase A2 (PLA2) is a family of enzymes that play different role(s) in inflammation, but their importance in seasonal allergic rhinitis (SAR) has not been clarified. Here, we determined the levels of messenger ribonucleic acid (mRNA) for different PLA2 types in the nasal mucosa of SAR patients (n = 6) and healthy controls (n = 5). Nasal brush samples were taken both during pollen season, when the symptoms of the patients were severe, and off-season, when the patients were free of symptoms.

Clara cell 10-KDA protein inhibits endotoxin-induced airway contraction in isolated perfused rat lungs.

Clara cell 10-kDa protein (CC10) is a major component of bronchoalveolar lavage fluid and is suggested to be a natural regulator of airway inflammation, possibly through its effects on the proinflammatory enzyme(s), phospholipase A2. We examined the effect of recombinant human (rh) CC10 on endotoxin-induced airway contraction and cytokine release in isolated perfused rat lungs. We found that rhCC10 added to the lung perfusate abolished the endotoxin-induced airway contraction, and that it inhibited both the release of interleukin-1 beta and interleukin-6 into the lung perfusate and the release of tumor necrosis factor-alpha into the pulmonary lavage fluid.

Increased gene expression of novel cytosolic and secretory phospholipase A(2) types in human airway epithelial cells induced by tumor necrosis factor-alpha and IFN-gamma.

Phospholipase A(2) (PLA(2)) is a growing family of enzymes that may play a major role in inflammation. We investigated the effect of tumor necrosis factor-alpha (TNF-alpha) and interferon-gamma (IFN-gamma) on the gene expression of 19 different PLA(2) types (IB, IIA, IID, IIE, IIF, III, IVA, IVB, IVC, V, VIA, VIB, VIIA, VIIB, VIIIA, VIIIB, X, XII, and XIII) in human bronchoepithelial (BEAS-2B) and nasal epithelial (RPMI 2650) cells. The cells were stimulated with TNF-alpha or IFN-gamma for different lengths of time (1, 4, 18, and 48 h), and the mRNA levels of the different PLA(2) types were determined by reverse transcriptase-PCR (RT-PCR) and normalized to those of the housekeeping gene, GAPDH.