The viability of splenocytes from (□) wild-type (p53^+/+) and (▧) null (p53^−/−) murine splenocytes after 24 hours of incubation with varying concentrations of flavopiridol. Error bars indicate 95% CIs. The cells were obtained from spleens of typed and PCR confirmed p53^+/+ and p53^−/− mice. These cells were cultured at 1 × 10⁶/mL in medium (control) and varying concentrations of flavopiridol (0.01 to 1 μmol/L). After 1 day of incubation, the viability was assessed using the Trypan blue exclusion test.