Another study purified antibodies against Chlamydia pneumoniae outer membrane proteins (OMPs) from serum of AAA patients, and used these antibodies to analyze the aortic walls of AAA patients with western blot and found positive reactions in all of the tested samples, which could be an evidence of the association between the Chlamydia pneumoniae OMP antigens and AAA (108). The gene discussed is OMP; the disease is triple-A syndrome.