Anti ccr6 pe

The following anti-human monoclonal antibodies were used for surface phenotype and intracellular cytokine staining: anti-CD4-fluorescein isothiocyanate (FITC); anti-CD4-phycoerythrin (PE); anti-CD161-PE; anti-CCR6-PE; anti-CD45RO-PE; anti-CD147-peridinin chlorophylla protein cyanine 5.5 dies (Percp–cy5.5); anti-interferon (IFN)-γ-FITC (all from BD Biosciences); and anti-IL-17A-allophycocyanin (APC; eBiosciences). Anti-mouse monoclonal antibodies included: anti-CD4-Percp; anti-IL-17A-APC; and anti-IFN-γ-FITC (all from BD Biosciences). Appropriately conjugated IgG antibodies were used as isotype controls. Cells were acquired on a FACSCalibur flow cytometer (BD Biosciences) and analyzed using Cell Quest software (BD Bioscience) and FlowJo 7.6.1 software (Tree Star).

PBMCs were stimulated with HBV core 18–27 epitope (HBc 18–27, sequence: FLPSDFFPSV; final concentration: 10 μg/mL) in the presence of Brefeldin A (final concentration: 10 μg/mL) for 12 h. Cells were harvested and transferred to FACS tubes, and were stained with anti-CD4-PerCP (BD Bioscience, San Jose, CA, USA), anti-CD25-APC (BD Bioscience), and anti-CD127-FITC (BD Bioscience) for 20 min in the dark at 4 °C. Cells were washed twice with Staining Buffer (BD Bioscience), and were resuspended with 250 μL of Fixation/Permeabilization solution (BD Bioscience) for 20 min at 4 °C. Cells were then washed twice in 1 × BD Perm/Wash buffer (BD Bioscience), and were stained with anti-IL-17-PE (BD Bioscience) for 30 min in the dark at 4 °C. In certain experiments, purified CD4⁺CD25⁺CD127^dim/− Tregs were stained with anti-CCR4-FITC (BD Bioscience) and anti-CCR6-PE (BD Bioscience) for 20 min in the dark at 4 °C. Isotype antibodies were used to separate positive and negative cells in PerCP, APC, FITC, and PE fluorescence channels. Samples were analyzed with FACS Calibur analyzer (BD Bioscience). Acquisitions were performed with CellQuest Pro Software (BD Bioscience), and analyses were performed with FlowJo Version 8.4.2 for Windows (Tree Star, Ashland, OR, USA).