Inflammatory abdominal aortic aneurysm and the associated T-cell reaction: a case study.

The immune response associated with an inflammatory abdominal aortic aneurysm was studied by determining the phenotypes of lymphocytes in the peripheral blood, the aortic aneurysm wall, and the perianeurysmal tissue. Increased numbers of activated T cells were found in all three areas. After aneurysm repair, peripheral blood analysis demonstrated normalization of the T-cell subsets. These data suggest that inflammatory abdominal aortic aneurysm is associated with a measurable immune response in peripheral blood with elevation of the same subset of inflammatory cells (CD4) as detected in abdominal aortic aneurysm tissue, and the immune response regresses after aneurysm repair.