FIG. 7.

Transduction after release from serum deprivation. Retroviral vectors were added to confluent, serum-deprived human fibroblasts, and 2, 4, 6, or 10 days later (days before release) the cells were stimulated to divide by replating in larger wells and increasing the concentration in serum from 0.5 to 10%. Forty-eight hours after replating, AP staining was performed; the number of AP⁺ foci in released cultures divided by the number of AP foci in dividing cultures (R/D ratio) is reported for three independent experiments with standard errors (error bars).