Cell aging in vitro (author's transl)]

Human diploid fibroblast cultures in the phase of degeneration were compared with logarithmically-growing young cultures. Old cultures contain cells of increased size showing all signs of intact protein synthesis by means of the light and the electron microscope. DNA synthesis and cell division do not occur in old cultures. Premature chromosome condensation is still possible in old cells after fusion with mitotic cells of a fast-growing culture.