01 EU/μg pDNA by the Triton X-114 extraction. For polyI:C and imiquimod, polymyxin B, which binds to LPS, was added to cells at a final concentration of 5 μg/mL. ODNs, nucleotides and nucleosides were used as obtained without further purification or addition of polymyxin B. TLR9 KO mice were purchased from the Oriental Yeast Company (Tokyo, Japan). C57BL/6 WT mice Anti-infection Compound Library high throughput and Institute for Cancer Research (ICR)

mice were purchased from Japan SLC (Shizuoka, Japan) and maintained on a standard food and water diet under conventional housing conditions. All animal experiments were conducted in accordance with the principles and procedures outlined in the National Institutes of Health Guide for the Care and Use of Laboratory Animals. The protocols for animal experiments were approved by the Institutional Animal Experimentation Committee of the Graduate School of Pharmaceutical Sciences, Kyoto University. In the experiment of subcutaneous injection

of ODN into mouse footpad, 3 nmol of ODN1668 in 20 μL PBS were subcutaneously injected into the footpad of the right hind leg of male ICR mice with or without 10 nmol DNase I-treated or untreated ODN1720. Before and 24 h after injection of ODN, the thickness of footpad was measured using a micrometer caliper with a minimum scale of 10 μm (Mitutoyo, Kawasaki, Japan). Separately, the footpad was removed at 24 h after injection and submerged into

4% paraformaldehyde in PBS for 24 h at 4°C. The fixed footpad tissues MLN8237 supplier were decalcified and embedded in paraffin and sectioned into 3-μm slices. The paraffin sections were stained with hematoxylin and eosin to evaluate the infiltration of blood cells. The number of mononuclear cells and neutrophils infiltrating into the injection site in 25 mm2 was counted. Splenic macrophages were collected as previously described 16 and cultured on 96-well culture plates at a density of 3×105 cells/well in RPMI-1640 medium supplemented with 10% fetal bovine serum (FBS), penicillin G (100 U/mL), streptomycin (100 μg/mL), L-glutamine (292 μg/mL) and 2-mercaptoethanol (10−5 M). They were used for the cytokine release experiment soon after isolation. The murine macrophage-like cell line, RAW264.7 cells, was cultured before on 96-well culture plates at a density of 5×104 cells/well in RPMI-1640 supplemented with 10% FBS, penicillin G (100 U/mL), streptomycin (100 μg/mL) and L-glutamine (292 μg/mL). They were cultured for 24 h prior to use. The human leukemic plasmacytoid DC line, PMDC05 cells 17, was cultured on 96-well culture plates at a density of 4×105 cells/well in Iscove’s Modified Dulbecco’s Medium supplemented with 10% FBS, penicillin G (100 U/mL), streptomycin (100 μg/mL) and L-glutamine (292 μg/mL). They were plated before the cytokine release experiment. RAW264.