Figure 1.

Sodium oleate is sufficient to induce a regulatory phenotype in MSC-2 cells. MSC-2 cells were incubated in the presence or absence of IL-4 (100 ng/ml) for four days as indicated, followed by the analysis of their inhibitory potency: Purified CD4⁺ T cells were co-cultured with MSC-2 cells in the presence or absence of IL-4 in a ratio of 1:5. T cell proliferation was analyzed by CFSE staining after 72 h (A). After a four-day culture of MSC-2 cells in the presence or absence of IL-4 (100 ng/ml), arginase activity was determined (B). Purified CD4⁺ T cells were co-cultured with MSC-2 cells in the presence or absence of IL-4, sodium oleate (0.2 mM) or a neutralizing IL-4 antibody (10 µg/ml) as indicated. T cell proliferation was analyzed by CFSE staining after 72 h (C). Shown is the mean ± SD from two to three independent experiments. *p ≤ 0.05; **p ≤ 0.01.