Evidence for in vitro senescence of T-lymphocytes cultured from normal human peripheral blood

Long-term T-cell cultures from 15 donors of various ages were established using T-cell growth factor (TCGF). The donors were divided in equal numbers into three age groups, under 40, 40 to 80 and over 80 years of age. The cell cultures showed a growth pattern similar to the Hayflick Phenomenon observed in the cultured human fibroblasts with a limited total number of doublings. Cell cultures from younger groups grew longer with higher total number of doublings. The total number of doublings averaged 16.5, 12.2 and 6.5 for the cultured cells obtained from donors under 40, 40 to 80 and over 80 years of age respectively.