Detection of Chlamydia pneumoniae in aortic lesions of atherosclerosis by immunocytochemical stain.

TLDR

Recent evidence shows Chlamydia pneumoniae antigens and nucleic acid in coronary artery atheromas from South African autopsy patients. This study aimed to demonstrate C. pneumoniae antigens in aortic atheromas using immunocytochemical techniques in autopsy patients from University of Washington aortic atherosclerosis studies. Immunoperoxidase and double‑label immunocytochemical staining with Chlamydia‑specific monoclonal antibodies was performed on aortic lesions from 34‑58‑year‑old patients, localizing antigens to macrophages and smooth muscle cells.

Abstract

Recent evidence has shown the presence of Chlamydia pneumoniae antigens and nucleic acid in coronary artery atheromas from autopsy patients in South Africa. In this study, the immunocytochemical technique was used to demonstrate C pneumoniae antigens in atheromas of the aorta in autopsy patients from retrospective aortic atherosclerosis studies at the University of Washington. The patients were 34 to 58 years old. Immunoperoxidase staining using Chlamydia-specific monoclonal antibodies showed one of four fatty streaks and six of 17 fibrous plaques were positive for C pneumoniae antigens; four control aortic tissues were negative. Two of the positive plaques were from the same patient. Double-label immunocytochemical staining using Chlamydia- and tissue type-specific monoclonal antibodies demonstrated the antigens in the cytoplasm of macrophages and smooth muscle cells in the atheromatous lesion. This study suggested a wider involvement of C pneumoniae organisms in atherosclerotic lesions of the arterial system than has previously been documented.