Neointimal smooth muscle cells in human cardiac allograft coronary artery vasculopathy are of donor origin.

Background: Transplant coronary artery vasculopathy (CAV) is a fibro-proliferative process that leads to lumen occlusion and cardiac failure. Current theories suggest that the process evolves over time in response to inflammation and proliferation of donor derived medial smooth muscle cells (SMC). Animal models of cardiac transplantation have suggested that the neointima is formed by recipient derived circulating progenitor cells.