Cells were washed once with Hanks’s balanced salt solution and cultured in Dulbecco’s modified Eagle’s medium (DMEM) (Hyclone, Logan, UT, USA) supplemented with 5% fetal
calf serum (Gibco, Paisley, UK), 1% L-glutamine (Sigma, St Louis, MO, USA), 1% non-essential amino acids (Sigma), 2 × 10−5 M 2-mercaptoethanol (Amresco, Solon, OH, USA), 100 U/ml penicillin and 100 μg/ml streptomycin (Gibco). All cells were adjusted to 2 × 106 cells/ml. MNC suspensions (4 × 105) obtained above were seeded in triplicate in 96-well, round-bottomed microtitre plates at different lymphocyte : astrocyte ratios (10:1, 1:1 and 1:5). Cells were stimulated with 25 μg/ml MOG35–55 peptide for Ibrutinib ic50 72 h. For anti-CD3/CD28-induced
cell proliferation, 96-well culture plates were coated with purified anti-CD3 and anti-CD28 monoclonal antibodies (mAbs) (5 μg/ml each; eBioscience, Ltd, Ireland, UK). ConA (Sigma, St Louis, MO, NVP-AUY922 nmr USA) was used at 5 μg/ml. Proliferation was measured by [3H]-thymidine (specific activity, 60 μCi/mmol; Institute of Atomic Energy, China; 0·5 μCi/well) incorporation after 72 h in complete DMEM medium. Astrocytes were cultured at a concentration of 1 × 106 cells/well in 12-well plates, then incubated with 2 μg/ml goat anti-mouse-IL-27 antibody (R&D Systems, Minneapolis, MN, USA) [37] or isotype control immunoglobulin (Ig)G2a in 2 ml medium for 12 h to neutralize IL-27. ifoxetine Astrocytes were co-cultured with MNCs (1 × 107) harvested from the lymph nodes of EAE mice in 2 ml lymphocyte culture medium. The cells were incubated at 37°C, 5% CO2 for 72 h. Supernatants were collected for measurement of the levels of soluble cytokines. Astrocytes (1 × 106) were co-cultured with lymph node lymphocytes (1 × 107) harvested from 7 dpi mice in 2 ml lymphocyte culture medium. Where indicated, lymphocytes were also seeded in Transwell™ insert (24-well plates, 3 μm pore size;
Corning, NY, USA). Twenty-five μg/ml MOG35–55 peptide was incubated as antigen and the supernatants were collected 72 h later. Measurement of cytokine levels in cell culture supernatants was performed by enzyme-linked immunosorbent assay (ELISA) using commercially available ELISA kits, in accordance with the manufacturer’s instructions. IFN-γ, IL-17 and IL-4 ELISA kits were purchased from Peprotech (Rocky Hill, NJ, USA). The TGF-β ELISA kit was obtained from Boster, China. Results are expressed as pg/ml. Total RNA was prepared from spinal cords or lymph node MNCs using TRIzol reagent (Invitrogen). cDNA was synthesized using a reverse transcription–polymerase chain reaction (RT–PCR) kit from TaKaRa (Kyoto, Japan). RT–PCR was used to detect MHC-II genes using the following forward 5′-GATCGGATCCAACCCTGCTGAGGATTCA-3′ and reverse 5′-GATCGGATCCTGTCCTCGGCTGGGAAGA-3′ primers.