Activation of immune cells from TBLN. Cells from TBLN of OVA- and SNP/OVA-mice (10 μg SNP) were stained for expression of surface molecules, including CD4, CD69, CD11c, CD11b, MHC II, and Gr-1. Cells were gated on singlets using FSC-A/FSC-H, lymphocytes, monocytes, or granulocytes using FSC-A/SSC-A, and individual cell populations, including CD4+ cells, CD11c+, Gr-1+, CD11c+Gr-1+CD11b- pDC, CD11c+Gr-1-CD11b- AM. More details on the gating strategy are found in the supplementary information (Additional file 1: Figure S6). Expression of CD69 on CD4+ cells (A), Gr-1+ cells (B), CD11c+ cells (C), pDC (D), and AM (E), and expression of MHC II on CD11c+ cells (F) are presented in histograms, with X axis representing mean fluorescence intensity for CD69 or MHC II and Y for % of particular gated cell population. Six samples from OVA- (grey curve) or OVA/SNP- (black curve) mice were concatenated for flow cytometric analysis. Statistical analysis of percent values of CD69 expression from individual TBLN revealed a significant difference in CD11c+, AM, and pDC populations between OVA and SNP/OVA-mice.