IMPACT DES PARTICULES DIESEL ET DES ACARIENS SUR LES CELLULES EPITHELIALES BRONCHIQUES HUMAINES (ALTERATION DES INTERACTIONS CELLULE-MATRICE EXTRACELLULAIRE)

PARIS12-CRETEIL BU Multidisc. (940282102) / SudocSudocFranceF

Biological markers in pneumoconioses : plasma metalloendopeptidase and matrix metalloendopeptidase

International audienceThe design and validation ofbiomarkers can contribute significantly to early detection of biological effects and identification ofthose who are at risk ofcoal workers' pneumoconiosis (CWP). This research is designed to evaluate diflerent plasma metalloendopeptidase and metalloproteinase activities to estimate harmfui exposure in coalminers from difierent roining regions (North, Lorraine and Provence) in France and to relate the outcome to diflerences in prevalence ofCWP between these regions

Role of collagenase in mediating in vitro alveolar epithelial wound repair.

International audienceType II pneumocytes are essential for repair of the injured alveolar epithelium. The effect of two MMP collagenases, MMP-1 and MMP-13 on alveolar epithelial repair was studied in vitro. The A549 alveolar epithelial cell line and primary rat alveolar epithelial cell cultures were used. Cell adhesion and cell migration were measured with and without exogenous MMP-1. Wound healing of a cell monolayer of rat alveolar epithelial cell after a mechanical injury was evaluated by time lapse video analysis. Cell adhesion on type I collagen, as well as cytoskeleton stiffness, was decreased in the presence of exogenous collagenases. A similar decrease was observed when cell adhesion was tested on collagen that was first incubated with MMP-1 (versus control on intact collagen). Cell migration on type I collagen was promoted by collagenases. Wound healing of an alveolar epithelial cell monolayer was enhanced in the presence of exogenous collagenases. Our results suggest that collagenases could modulate the repair process by decreasing cell adhesion and cell stiffness, and by increasing cell migration on type I collagen. Collagen degradation could modify cell adhesion sites and collagen degradation peptides could induce alveolar type II pneumocyte migration. New insights regarding alveolar epithelial cell migration are particularly relevant to investigate early events during alveolar epithelial repair following lung injury