Abstract 494: Proinflammatory Role of Stem Cells in Abdominal Aortic Aneurysms

Background: The pathogenesis of abdominal aortic aneurysm (AAA) formation includes inflammation, vascular smooth muscle cell apoptosis, extracellular matrix degradation and oxidative stress. It is well established that multi-potent stem cells have an important role in cardiovascular health and disease but the role of stem cells in AAA formation remains controversial. We sought to describe the presence of stem cells in human AAA tissue. Additionally, we investigated the differentiation of stem cells within the aneurysmal aorta. Methods: Infra-renal aortic wall specimens (8 AAA patients; 5 males and 3 females; ages ranging from 55 to 78 years) were collected from patients undergoing AAA repair operations. Non-aneurysmal infra-renal aortic control samples were collected at autopsies (N=5; 3 males and 2 females; donor ages ranging from 53 to 78 years). Using immunohistochemistry, we compared the abundance of STRO1+, cKit+, and CD34+ cells in aortic tissue. Using double immunofluorescence staining, we evaluate...