Donor age reflects the replicative lifespan of human fibroblasts in culture.

Human fibroblasts, which have a finite lifespan in cultures, have been widely used as a model system for cellular aging, and frequently used as one model of human aging. But whether cellular aging contributes to organismal aging has been controversial. To reinvestigate this question, we cultured human fibroblasts from the skin of one individual volunteer collected at different ages. Over a period of 27 years (donor age 36 years to 62 years), we obtained skin cells four times at appropriate intervals, and established eight fibroblast lines. These human fibroblasts have presented evidence for a correlation between donor age and proliferative lifespan in vitro. This result parallels the fact that telomeric DNA size cultured fibroblasts decrease with the increase in donor age. These cell lines had a normal diploid human chromosome constitution and will be useful in studies of human biology including aging.