Human arterial smooth muscle cell strains derived from patients with moyamoya disease: changes in biological characteristics and proliferative response during cellular aging in vitro.

Moyamoya disease is a progressive cerebrovascular occlusive disease that occurs frequently in children. The etiology is unknown. We examined changes in biological characteristics and responsiveness to serum mitogens during the in vitro cellular aging of arterial smooth muscle cell strains derived from patients with moyamoya disease (HMSMC) and compared them with those of cells from age-matched control patients (HCSMC). HMSMC had a normal human diploid chromosome constitution. HMSMC and HCSMC had almost the same in vitro life span and the age-related patterns of biological parameters were essentially the same. However, the doubling time at the early passages was significantly longer in moyamoya SMC than control SMC, although there was no significant difference at the late passages. Furthermore, the poor responsiveness of moyamoya SMC to platelet-derived growth factor was retained throughout the life span in vitro. These results support the hypothesis that functional alterations in vascular cells are involved in the mechanism of development of intimal thickening in moyamoya disease.