Comparison of doubling numbers attained by cultured animal cells with life span of species

Abstract

HUMAN fibroblasts in culture undergo 40–60 cell doublings (indicating numbers of cell generations) before the growth rate declines and death of cells ensues¹. Hayflick² has suggested that the final doubling numbers achieved by cultured diploid cells may be related to the life span of the animal species from which the cells were derived. This suggestion is based on reported final doubling numbers for human, chicken and mouse being in the ranges 40–60, 15–35, and 14–28, whereas the maximum life span of each of these species was 110, 30 and 3.5 yr, respectively. We report here findings on final cell doubling numbers attained when cells from ten different animal species were serially subcultured. Tissues of foetal or newborn origin were used to initiate cultures from man, horse, monkey, cat and dunnart, and the cultures of wallaroo×red kangaroo hybrid, kangaroo, wallaby, rabbit and potoroo, were derived from adult tissues.