Development of a tropoelastin-binding MR contrast agent for in vivo imaging of impaired elastogenesis in atherosclerosis

Background Elastin is a primary component of the vessel wall and present in all elastic vessels such as the aorta and the pulmonary artery. Elastogenesis begins with the synthesis and secretion of the soluble precursor tropoelastin that becomes cross-linked into insoluble elastin. Under normal conditions cross-linked elastin is the only form of the molecule present in the vessel wall whereas tropoelastin is absent. Conversely, under pathological conditions including atherosclerosis and aortic aneurysms elastogenesis resumes and tropoelastin molecules accumulate in the vessel wall. We developed a novel tropoelastin-binding MRI contrast-agent that would allow 1) specifically bind to tropoelastin but not to cross-linked mature elastin to allow 2) detection of pathologic elastogenesis that occurs in atherosclerosis and 3) minimizing non-specific signal from endogenously present mature elastin.