Medical certification of incapacity in guardianship applications: conceptualising capacity

Abstract

Fragestellung: Neutrophil (polymorphonuclear leukocytes [PMN]) accumulation within the synovial fluid of diseased joints in rheumatoid arthritis (RA) is a distinct event in the early stages of the disease. The recruitment of PMNs to inflamed joints involves a sequence of complex cellular events including directed chemotaxis to the inflammatory site. Given the crucial role of Ca2+ transients in chemotactic signaling and responses, we assessed the role of the putative Ca2+entry channel TRPC6 in PMN chemotaxis.Methodik: Neutrophils were isolated from the bone-marrow of 8-10 weeks old TRPC6 knockout mice and age matched wild type controls. Chemotaxis analysis was performed in 3-dimensional collagen-I matrices (2.5mg/ml) on fibronectin coated (1mug/cm2) chemtoaxis chambers and quantified by time-lapse videomicroscopy. PMN migration was elicited using gradients of either N-formyl-methionyl-leucyl-phenylalanine (fMLP) or cell-free inflammatory exudates obtained from the acute phases of peritonitis induced in these mice by a 9% casein solution. Additionally, we inhibited the CXCR2 receptor by adding CXCR2 receptor blocker SB225002 to the inflammatory exudate gradient.Ergebnisse: Neutrophils were isolated from the bone-marrow of 8-10 weeks old TRPC6 knockout mice and age matched wild type controls. Chemotaxis analysis was performed in 3-dimensional collagen-I matrices (2.5mg/ml) on fibronectin coated (1ig/cm2) chemtoaxis chambers and quantified by time-laps videomicroscopy. PMN migration was elicited using gradients of either N-formyl-methionyl-leucyl-phenylalanine (fMLP) or cell-free inflammatory exudates obtained from the acute phases of peritonitis induced in these mice by a 9% casein solution. Additionally, we inhibited the CXCR2 receptor by adding CXCR2 receptor blocker SB225002 to the inflammatory exudate gradient.Schlussfolgerung: The reduced chemotaxis of TRPC6 knockout neutrophils along an inflammatory exudate gradient and the lack of CXCR2 blocking effects in these neutrophils indicate that TRPC6 contributes to neutrophil chemotaxis to inflammatory sites as part of the CXCR2 receptor pathway.