Organ culture of human coronary artery following balloon angioplasty

Intimal smooth muscle cell proliferation is the primary cause of restenosis following balloon angioplasty. Its underlying basis and progression remain unclear. The authors developed an organ culture of human coronary artery subjected to balloon angioplasty in order to investigate the cellular and molecular basis of intimal proliferation in a preparation that maintained the anatomic relationships of the vessel wall. Artery segments obtained from the explanted hearts of transplant recipients were maintained at 37°C in culture medium containing 30% fetal bovine serum for fourteen days. Balloon angioplasty produced partial endothelial denudation and medial smooth muscle cell damage, both of which tended to be reversed after fourteen days in culture. Transverse histologic sections of cultured artery showed the development of a new intima containing smooth muscle cells identified by immunocytochemistry with anti-α-actin. Labeling of cultures with [ 3 H] thymidine showed proliferating cells in the neointima. The data demonstrate that intimal proliferation occurs in organ culture of human coronary artery subjected to balloon angioplasty. They also suggest the possibility that the smooth muscle cells in the neointimal layer are the result of both migration and proliferation.