Table 2. Cumulative population doubling of keratinocyte cultures from three donors (A, B and C) at the point of replicative senescence.

Culture condition	Donor A	Donor B	Donor C
Control	44	43	35
Rapamycin	71	57	34
Y‐27632	54	66	49
Rapamycin + Y‐27632	69	54	54