G. Dranoff, Dana-Farber Cancer Institute, Boston, MA, USA), replaced every other day. On day 6, BMDC were detached with enzyme-free digestion buffer (Sigma-Aldrich, St. Louis, MO, USA). BMDC pulsed with α-GalCer (200 ng/mL, Kirin) or vehicle (Tween-20) in medium for 3 h at 37°C. BMDC were subsequently washed with PBS and
fixed with 0.02% glutaraldehyde (Sigma-Aldrich) for 1 min selleck chemicals llc before being used in experiments. Single cell suspensions from spleens were prepared by standard techniques. Liver MNC were isolated as previously described 17 without prior Collagenase digestion. Briefly, livers were perfused with PBS, minced and iNKT cells were enriched by centrifugation in a two-step Percoll gradient. Enriched populations typically contained 20–30% iNKT cells. Human iNKT cell lines were
established by sorting PBMC with iNKT-mAb 6B11 and expanding with mitogen as described 26. Lines were maintained by periodic re-stimulations and purity checked with Vα24 mAb 26. iNKT cells from livers were stimulated in the presence of either plate-bound PBS57-loaded CD1d monomers or α-GalCer-pulsed and Glutaraldehyde-fixed BMDC. PBS57-loaded CD1d monomers were plate-bound overnight in PBS at 4°C, blocked and washed with complete culture medium before cells were added. Cytokine-specific ELISA assays (eBioscience, San Diego, CA, USA) were performed following the manufacturers instructions. Sera were diluted 1:10 in PBS/1% BSA. RNA isolations using TRIzol (Invitrogen, Carlsbad, CA, USA) and RT reactions were performed as described 27. Real-time
click here PCR using 1/20 volume of reverse check details transcription reactions and primers specific for adenosine receptors A1R (F, 5′-CATTGGGCCACAGACCTACT-3′, R, 5′- CAAGGGAGAGAATCCAGCAG-3′), A2aR (F, 5′- CACGCAGAGTTCCATCTTCA-3′, R, 5′-ATGGGTACCACGTCCTCAAA-3′), A2b (F, 5′- TGCTCACACAGAGCTCCATC-3′ R, 5′- AGTCAATCCAATGCCAAAGG-3′), A3R (F 5′-GCTGATCTTCACCCATGCTT-3′, R, 5′- ATCCAAACTGACCACGGAAC-3′), and GAPDH (F, 5′-aactttggcattgt-3′, 5′-acacatttgggggta-3′) were performed using Quantitect SYBR Green in a Corbett (Qiagen, Valencia, CA, USA). Target gene expression was normalized against levels of GAPDH and normalized against standards with known copy numbers (102–105/reaction) of adenosine receptors. Subsequent to blocking with anti-CD16/32 mAb cells were stained with CD3-FITC, NK1.1-PE and CD1d tetramer-APC. NKT cells were gated as CD3+NK1.1+CD1d-tetramer+ and sorted to purities >95% using a FACSAria (all BD Biosciences, San Jose, CA, USA). Intracellular stainings for IL-4 and IFN-γ were performed using Cytofix/cytoperm (BD Biosciences) according to manufacturer’s instructions. Results are expressed mean±SD. For statistical analyses, the one-way-ANOVA with Newman-Keuls post-test was used. Values of p<0.05 were considered as significant.