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[Cell culture as an experimental system for studying aging processes].

The investigation of cellular aging has mainly been limited by experimental and descriptive work on two separate cell culture systems. On one hand studies were performed on in vitro aging, comparing fibroblasts in early and late passage. On the other hand, fibroblasts derived from donors of different age were compared (in vivo aging). Recently, results have been achieved, stating that some of the investigated parameters change similarly in both systems. Therefore it is of great importance to find criteria for cellular aging, not only to precise the results in both cell culture systems, but also to be able to draw conclusions concerning aging of the organism in vivo.