RESUMO
Treatment of primary or immortalized human airway epithelial cells (16HBE14o-, S9) or alveolar cancer cells (A549) with recombinant hemolysin A (rHla), a major virulence-associated factor of Staphylococcus aureus, induces alterations in cell shape and formation of paracellular gaps in the cell layer. Semiquantitative Western blotting using extracts of freshly isolated airway tissue (nasal epithelium) or 16HBE14o- model cells revealed that phosphorylation levels of focal adhesion kinase (Fak) and paxillin were altered upon treatment of tissue or cells with rHla. Immune fluorescence analyses showed that rHla treatment of 16HBE14o- cells results in losses of vinculin and paxillin from focal contacts and a net reduction in the number of focal contacts. The actin cytoskeleton was strongly remodeled. We concluded that treatment of cells with rHla activates Fak signaling, which accelerates focal contact turnover and prevents newly formed focal contacts (focal complexes) from maturation to focal adhesions. The inability of rHla-treated cells to form stable focal adhesions may be one factor that contributes to gap formation in the cell layer. In vivo, such changes may disturb the defensive barrier function of the airway epithelium and may facilitate lung infections by S. aureus.
Assuntos
Células Epiteliais/metabolismo , Matriz Extracelular/metabolismo , Pneumonia Estafilocócica/metabolismo , Mucosa Respiratória/metabolismo , Staphylococcus aureus/metabolismo , Toxinas Bacterianas/genética , Adesão Celular/genética , Linhagem Celular , Células Epiteliais/patologia , Matriz Extracelular/genética , Feminino , Quinase 1 de Adesão Focal/genética , Quinase 1 de Adesão Focal/metabolismo , Adesões Focais/genética , Adesões Focais/metabolismo , Adesões Focais/patologia , Proteínas Hemolisinas/genética , Humanos , Masculino , Paxilina/genética , Paxilina/metabolismo , Fosforilação/genética , Pneumonia Estafilocócica/genética , Pneumonia Estafilocócica/patologia , Mucosa Respiratória/patologia , Transdução de Sinais/genética , Staphylococcus aureus/genética , Vinculina/genética , Vinculina/metabolismoRESUMO
How do you feel after drinking milk or soy milk? The aim of this preliminary study was to find out if it is possible to measure the psychological effects of staple food items using a consumer test (according to DIN 10974), assessing the mental state of the participants. Results of two tests with dairy products and non-dairy milk substitutes, two vegetable tests, and two tests with bakery products are presented and discussed in the context of the further development of a standardized and validated test to measure the effects of food on the human mental state.