Angiogenesis is associated with mononuclear inflammatory cells in abdominal aortic aneurysms

To evaluate the extent of neovascularisation in abdominal aortic aneurysms, specimens from the aneurysm walls of 17 consecutive patients (14 men, mean age 69 years, range 59 to 79 years) were studied and compared with specimens from patients with aortoiliac occlusive disease (n = 8, five men, mean age 53 years; range 40 to 71 years). Routine histology was performed after haematoxylin and eosin, Verhoeff's elastic and periodic acid-Schiff stainings. For immunophenotypic analysis of inflammatory cells four monoclonal mouse antibodies (UCHL1, L26, PG-M1 and KP1) were used.

The histological sections through the walls of the AAAs showed extensive destruction of elastin and variable inflammation. Dense neovascularisation was seen throughout the aortic wall in the AAA cases compared to a mild angiogenetic response seen only occasionally in the AODs.

Angiogenesis may play a significant role in the AAA process by recruiting and carrying a macrophage-rich infiltrate to the aortic wall.