Figure 4. Effect of TGF-β-induced Tregs on macrophage cytokine production in the pancreas.

6–9 days after T cell transfer as described in Fig. 2, pancreata from 3–4 mice per group were harvested and pooled pancreatic cell suspensions were cultured for 5 h in the presence of brefeldin A before staining for intracellular cytokines. The histograms shown are gated on CD11b+ cells. In the experiment shown, IL-1β and MIP-1α but not TNF or MIP-1β production was suppressed. Histogram outlines indicate isotype control staining and shaded histograms indicate cytokine-specific staining. In four repeats of this experiment, we observed IL-1β and MIP-1α reduction in two cases.