Cytokine pattern in aneurysmal and occlusive disease of the aorta

Background. Prominent inflammatory infiltrates of macrophages and T-lymphocytes are found in both aortic occlusive disease (AOD) and abdominal aortic aneurysms (AAA). These cells secrete different cytokines that might affect matrix turnover through modulation of matrix metalloproteinase expression. A different cytokine pattern might account for the evolution of AOD vs AAA. Materials and Methods. Six different cytokines were examined to determine whether AOD and AAA could be characterized by unique cytokine patterns. AOD (n = 8) and AAA (n = 8) tissues were collected and serially treated with salt, dimethyl sulfoxide, and urea buffers to extract the soluble matrix or cell-bound cytokines. Levels of IL-1beta, TNF-alpha, IL-10, IL-12, and IFN-gamma were measured by immunoenzymatic methods. Additionally, RNA levels of IL-12 and IFN-gamma were measured. Results. AAA tissue contained higher levels of IL-10 compared to AOD tissue (P < 0.05). Higher levels of the proinflammatory cytokines IL-1β, TNF-α, and IL-6 were found in AOD (P < 0.05). mRNA levels of IL-12 and IFN-gamma did not differ between the diseases. Aortic tissues contained large amounts of matrix or cell-bound cytokines. Conclusions. AAA is characterized by greater levels of IL-10 while IL-1beta, TNF-alpha, and IL-6 are higher in AOD. Targeted deletion of these cytokines in animal models might help in identifying their role in the progression of AAA. (C) 2001 Elsevier Science.