FIG. 4.

Effector molecules are regulated normally in memory and naive T cells in G_0(A). (A) T lymphocytes maintained in G₀ by cdk inhibition by TAT-p16^INK4A or roscovitine (20 μM) produce IL-2 and IFN-γ, upregulate CD69 and CD44, and downregulate CD62L when stimulated for 24 h with PMA and ionomycin. (B) CD4⁺ naive T cells (95% CD45RO⁺ and CD8⁺) also produce IL-2, upregulate CD69, and downregulate CD62L in response to PMA and ionomycin when maintained in G₀ by TAT-p16^INK4A. The level of IFN-γ produced was below the limits of detection. The data shown are each representative of three separate experiments.