Fig. 2.

IL-6 stimulates IL-10 production by CM005 melanoma cells. a Increase in IL-10 in response to exogenously added cytokines. The levels of IL-10 produced by CM005 cells were measured after 2-day incubation with various concentrations (1, 10, and 100 folds of levels in medium of LPS-stimulated adherent PBMC) of individual cytokines (IL-1β, IL-6, IL-12, and TNF-α). Only IL-6 promoted IL-10 production by CM005 cells. b Anti-IL-6 antibody abrogated stimulative effects of LPS-activated PBMC supernatant. c IL-10 production in response to exogenously added IL-6. Exogenously added IL-6 promoted the production of IL-10 by melanoma cells in a dose-dependent manner (P < 0.01)