Densitometric analysis confirmed differences in expression for 20 of these gene products between AAAs and normal aorta, with the greatest increases seen for myeloid cell nuclear differentiation antigen (31-fold), cathepsin H (30-fold), platelet-derived growth factor-A (23-fold), apolipoprotein E (13-fold), gelatinase B/matrix metalloproteinase-9 (12-fold), and interleukin-8 (11-fold).