Effect of overexpression of the cyclin-dependent kinase inhibitor p27Kip1. Human blood monocytes differentiated for 4 days were infected with a recombinant adenovirus overexpressing p27kip1 (Ad:p27) or control, destabilized, enhanced green fluorescent protein at 1 × 108 plaque forming units/ml for 24 h. (A) p27kip1 protein overexpression by Western blotting. (B) BrdU was added 24 h after adenovirus infection in fresh medium for further 24 h and proliferation measured as percentage BrdU positive cells using immunocytochemistry. (C) A representative Western blot and relative levels of phosphorylated retinoblastoma protein. (D) A representative Western blot and relative levels H3pS-10. p Values were calculated using paired or single value t test. *indicates p < 0.05, **indicates p < 0.01 and ***indicates p < 0.001 compared with Ad:control. (E) Effect of p27 overexpression on the mRNA levels of genes regulated by IFN-γ and interleukin-4. p Values calculated using an ANOVA with Dunnett post-test, **indicates p < 0.01 compared with Ad:control. Data are presented as the mean ± SEM, n = 3 blood donors.