All experiments were performed in triplicate. Percentage of cytotoxicity was calculated as follows: [experimental counts per minute (cpm) −  spontaneous cpm]/[total cpm − spontaneous cpm] × 100. Freshly isolated PBMCs were stimulated with 25 ng/ml phorbol 12-myristate 13-acetate (PMA; Sigma-Aldrich) and 1 µg/ml ionomycin (Sigma-Aldrich) at 37°C in humidified 7% CO2 for 4 h. To block cytokine

secretion, brefeldin A (Sigma) [27] was added to a final concentration of 10 µg/ml. After addition of stimuli, the surface staining was performed with anti-CD4-PC5 (13B8·2), anti-CD8-PerCP (SK1) and anti-CD56-PC5 BGJ398 chemical structure (N901) (Beckman Coulter). Selleck MAPK Inhibitor Library Subsequently, the cells were permeabilized, stained for intracellular IFN-γ and IL-4 using the FastImmuneTM system (BD Pharmingen), resuspended in phosphate-buffered saline (PBS) containing 1% paraformaldehyde (PFA),

and analysed on a flow cytometer (≈ 10 000 gated events acquired per sample). ELISPOT assays were performed as described previously with the following modifications [28–30]. HLA-A24 restricted peptide epitopes, squamous cell carcinoma antigen recognized by T cells 2 (SART2)899 (SYTRLFLIL), SART3109 (VYDYNCHVDL), multi-drug resistance protein 3 (MRP3)765 (VYSDADIFL), MRP3503 (LYAWEPSFL), MRP3692 (AYVPQQAWI), alpha-fetoprotein (AFP)403 (KYIQESQAL), AFP434 (AYTKKAPQL), AFP357 (EYSRRHPQL), human telomerase reverse transcriptase (hTERT)167 (AYQVCGPPL) (unpublished), hTERT461 (VYGFVRACL) and hTERT324 (VYAETKHFL) were used in this study. Negative controls consisted of an HIV envelope-derived peptide (HIVenv584). Positive controls consisted of 10 ng/ml PMA (Sigma) or a CMV pp65-derived

peptide (CMVpp65328). The coloured spots were counted with a KS ELISPOT Reader (Zeiss, Tokyo, Japan). The number of specific spots was determined by subtracting the number of spots in the absence of antigen from the number of spots in its presence. Responses were considered positive if more than 10 specific spots were detected http://www.selleck.co.jp/products/ch5424802.html and if the number of spots in the presence of antigen was at least twofold greater than the number of spots in the absence of antigen. Serum cytokine and chemokine levels were measured using the Bioplex assay (Bio-Rad, Hercules, CA, USA). Briefly, frozen serum samples were thawed at room temperature, diluted 1:4 in sample diluents, and 50 µl aliquots of diluted sample were added in duplicate to the wells of a 96-well microtitre plate containing the coated beads for a validated panel of 27 human cytokines and chemokines (cytokine 27-plex antibody bead kit) according to the manufacturer’s instructions.