Ectopic expression of human and feline CD9 in a human B cell line confers beta 1 integrin-dependent motility on fibronectin and laminin substrates and enhanced tyrosine phosphorylation.

Few molecules have been shown to confer cell motility. Although the motility-arresting properties of anti-CD9 monoclonal antibody (mAb) suggest the transmembrane 4 superfamily (TM4SF) member CD9 can induce a motorgenic signal, gene transfection studies have failed to confirm this hypothesis. We report here that ectopic expression of human CD9 (CD9h) and feline CD9 (CD9f) in the CD9-negative, poorly motile, human B cell line Raji dramatically enhances migration across fibronectin- and laminin-coated polycarbonate filters. Migration of Raji/CD9h and Raji/CD9f on either substrate was inhibited by the anti-CD9 mAb 50H.19 and by the anti-beta 1 integrin mAb AP-138. Migration of Raji/CD9h on laminin was potently inhibited by the anti-VLA-6 integrin mAb GoH3 and by the anti-VLA-4 integrin mAb 44H6, whereas migration of Raji/CD9h on fibronectin was inhibited only by mAb 44H6. Since CD9h-transfected Raji cells adhered to fibronectin as effectively as mock transfectants, expression of CD9 enhanced motility, but not adhesion. CD9-enhanced migration was inhibited by the protein tyrosine kinase inhibitor herbimycin A suggesting that tyrosine phosphorylation played a role in the generation of a motorgenic signal. Raji/CD9h transfectants adherent to fibronectin expressed 6-fold higher levels of phosphotyrosine than Raji. Raji/CD9f transfectants also phosphorylated proteins on tyrosine more effectively than Raji including a protein of 110 kDa which was phosphorylated on the motility-inducing substrates laminin and fibronectin, but not on bovine serum albumin. Our results support a role for CD9 in the amplification of a motorgenic signal in B cells involving beta 1 integrins and the activation of protein tyrosine kinases.

[Mites as a cause of allergic diseases in humans]. / Roztocza jako przyczyna schorzen alergicznych u czlowieka.

The paper presents current views on the role of acarina in pathogenesis of allergic diseases and their occurrence in the human environment. The allergic species of acarina present both in the occupational and community environments were investigated. Basic methods for obtaining allergen extracts as well as immunological tests used for detecting allergy to those allergens are described. Some modes of combating acarina in the human environment are discussed.

Endotoxin in the occupational environment of bakers: method of detection.

The present study was conducted in a large mechanical city bakery. The AS-50 aspirators equipped with cellulose membrane filters were used for dust sampling. Airborne microbial content was assessed by means of sedimentation and aspiration using an Andersen sampler on Petri plates containing McConkey's medium. The following Gram-negative rods were detected in the bakery atmosphere: Erwinia herbicola, Acinetobacter Lwoffi and Klebsiella oxytoca, in concentrations ranging from 1.4 10(4) to 3.5 10(5) colony forming units per cubic meter (cfu/m3). Endotoxin concentration in flour dust sampled in selected work areas of the bakery ranged from 6.7 micrograms of endotoxin per gram of dust (micrograms/g) to 20.3 micrograms/g. Endotoxin level in the air was 0.04-0.05 micrograms of endotoxin per cubic meter (micrograms/m3). The results of our show that aspiration sampling is necessary for evaluation of airborne bacterial content and demonstrate the efficacy of the Limulus test of varying sensitivity to assay endotoxin level in the airborne dust. The advantage of this method is the possibility of assessing endotoxin in crude dust extracts.

[Biological effect of wood dust]. / Biologiczne dzialanie pylu drzewnego.

The biological effect of exposure to wood dust depends on its composition and the content of microorganisms which are an inherent element of the dust. The irritant and allergic effects of wood dust have been recognised for a long time. The allergic effect is caused by the wood dust of subtropical trees, e.g. western red cedar (Thuja plicata), redwood (Sequoia sempervirens), obeche (Triplochiton scleroxylon), cocabolla (Dalbergia retusa) and others. Trees growing in the European climate such as: larch (Larix), walnut (Juglans regia), oak (Quercus), beech (Fagus), pine (Pinus) cause a little less pronounced allergic effect. Occupational exposure to irritative or allergic wood dust may lead to bronchial asthma, rhinitis, alveolitis allergica, DDTS (Organic dust toxic syndrome), bronchitis, allergic dermatitis, conjunctivitis. An increased risk of adenocarcinoma of the sinonasal cavity is an important and serious problem associated with occupational exposure to wood dust. Adenocarcinoma constitutes about half of the total number of cancers induced by wood dust. An increased incidence of the squamous cell cancers can also be observed. The highest risk of cancer applies to workers of the furniture industry, particularly those dealing with machine wood processing, cabinet making and carpentry. The cancer of the upper respiratory tract develops after exposure to many kinds of wood dust. However, the wood dust of oak and beech seems to be most carcinogenic. It is assumed that exposure to wood dust can cause an increased incidence of other cancers, especially lung cancer and Hodgkin's disease. The adverse effects of microorganisms, mainly mould fungi and their metabolic products are manifested by alveolitis allergica and ODTS. These microorganisms can induce aspergillomycosis, bronchial asthma, rhinitis and allergic dermatitis.

The effect of subchronic exposure to the rubber vulcanization fumes on guinea pig lungs.

The influence of 28 days' inhalatory exposure to rubber vulcanization fumes at a concentration of 100 mg/m3 on guinea pigs' lung morphology was investigated. Focal infiltrations of pulmonary parenchyma with lymphocytes, neutrophilic and eosinophilic granulocytes and macrophages were observed. Lymphatic tissue concentrations having the typical appearance of solitary lymphatic nodules were also seen. The use of the double sequential Alcian blue/safranin O staining method for the identification of the mast cells [MCs] revealed that only Alcian-blue-positive MCs were observed, regardless of the region of the lungs examined, both in control and exposed guinea pigs. No safranin-0-positive MCs were seen. However, the MCs number increased from 1934 +/- 91 cells/mm3 tissue in controls to a statistically significant (p less than 0.05) 2486 +/- 89 cells/mm3 tissue in exposed guinea pig lungs. It was accompanied by histamine content increase from 1.50 +/- 0.06 micrograms/g wet tissue weight and 2.45 +/- 0.18 micrograms/g wet tissue weight, respectively. The distribution of the lung MCs varied, showing a statistically significant (p less than 0.05) increase in their number in the intraalveolar septa: from 957 +/- 53 to 1369 +/- 74 cells/mm3 tissue and in the peribronchial and peribronchiolar spaces: from 204 +/- 36 to 359 +/- 42 cells/mm3 tissue.

[Morphometric analysis of the rat lung after exposure to xylene vapors]. / Ocena morfometryczna pluc szczurów narazonych na pary ksylenu.

Pathomorphologic examinations of laboratory animals' respiratory system, carried out within evaluation of chemical substances toxicity, pose many diagnostic obstacles. Usually, pulmonary pathologies are evaluated based on arbitrarily adopted criteria and subjective "feelings" of a pathologist. To objectivize the results of pathomorphologic studies and evaluation of the usefulness of quantitative morphological techniques, morphometric tests of the lungs of rats exposed to m-xylene vapours of 4000 mg/m3 concentration for 1 and 3 months were carried out. Lungs were expanded by intratracheal insufflation of 10% formalin under controlled pressure of 23-25 cm water column. Using the stereological point--counting method, in microscope preparations evaluated was the relative volume of: a) normal and atelectatic lung parenchyma, b) peribronchial lymphatic tissue, c) interstitial inflammatory infiltrations. Pathological changes were presented in form of numbers; findings were analysed statistically with non-parametric tests of Krushal-Wallis and Mann-Whitney. The morphometric techniques demonstrated significant differences in the lungs of xylene-exposed rats, varying with the duration of exposure and applied dose, as compared to control animals.