Neutrophil chemotaxis and neutrophil elastase in the aortic wall in patients with abdominal aortic aneurysms.

To test the hypothesis that elastin-derived peptides (EDP) from human aortic tissue may be chemotactic for inflammatory cells, we studied the chemotaxis of neutrophils and monocytes to EDP derived from abdominal aortic aneurysm (AAA), aortic occlusive disease (AOD), and control aortas. In addition, we determined if neutrophils deliver neutrophil elastase to the aorta in vivo by staining for neutrophil elastase (NE) throughout the course of abdominal aortic aneurysms with the monoclonal antibody to human NE. EDP from AAA, AOD, and control tissue demonstrated significant chemotactic activity for both neutrophils and monocytes. All neutrophils had a greater attraction to EDP from AAA tissue compared to AOD and control aorta. Neutrophils from AAA patients were more attracted to EDP of AAA tissue than were neutrophils of AOD or control patients attracted to their respective aortic EDP. Neutrophil elastase stained positive in the adventitia and thrombus throughout the course of the aneurysm, but was not found in the intima, media, or plaque of the aorta.