Enhanced expression of a high-molecular-weight protein in arteriosclerotic plaques

We report the detection of a high-molecular-weight protein which is present in the 12,000 X g supernatant of arteriosclerotic plaques from the abdominal aortas of cockerels. The protein has a molecular weight of 160-170 kd when resolved via sodium dodecyl sulfate polyacrylamide gel electrophoresis (7.5%) in the presence of beta-mercaptoethanol. Densitometric scans of silver-stained gels indicate that the 160 kd protein is 8-10 times more prominent in plaques than in the underlying artery wall. This protein, which is present in all plaques analyzed to date, can be detected in animals as young as 8 weeks of age. This represents the first demonstration of the elaboration of a unique protein during the early stages of arteriosclerotic plaque development.