FIG. 6.

Involvement of PKC in Tat-induced production of IL-10. (A) Monocytes (10⁶) were treated or not with the PKC inhibitor RO318220 (RO) at the concentrations indicated (2.5 and 5 μM) or by the PKA inhibitor H89 (50 and 100 μM) for 30 min. Tat was then added for 24 h. These results are representative of three independent experiments done on cells from three donors. (B) Control of the specificity of the kinase inhibitors H89 and RO318220. Monocytes (10⁶) were treated or not with the PKC inhibitor RO318220 (2.5 and 5 μM) or by the PKA inhibitor H89 (50 and 100 μM) for 30 min. Rolipram was then added for 24 h. Culture supernatants were then collected, and the presence of IL-10 was determined by ELISA. (C and D) Monocytes were treated or not with PMA (50 or 100 ng/ml), a PKC activator, for 24 h (C) or 48 h (D), and Tat (10 nM) was then added. After 24 h, culture supernatants were recovered, and the presence of IL-10 was determined by ELISA. The values in C are the means ± SD of three experiments. The results in C and D are representative of three independent experiments done on cells from three donors.