Cells were treated with vehicle control (Cont), 30 nM 9cRA and/or 100 nM 1,25(OH)2D3 (D3) for 72 hours and secreted IL-10 levels in media were measured. **, p<0.01; ***, p<0.001 (one-way ANOVA followed by Tukey’s multiple comparisons). n.d., not detected.