Z vrpr fmk

Splenic B cells were purified by depleting CD43⁺ cells with magnetic beads using AutoMACS (Miltenyi Biotec, Bergisch-Gladbach, Germany). B cells from mice were cultured in Iscove's modified Dulbecco's medium supplemented with 10% fetal bovine serum and 1% penicillin–streptomycin. The antibodies for extracellular signal-regulated kinase, NIK, RelB, NF-κB2 and phospho-NF-κB2 were purchased from Cell Signaling Technology Inc. (Beverly, MA, USA) and anti-CD40 monoclonal antibody and anti-GAPDH were obtained from BD Biosciences. Lipopolysaccharide purified from Escherichia coli 055:B5 was purchased from Sigma-Aldrich (St Louis, MO, USA) and mouse recombinant BAFF was purchased from R&D Systems (Minneapolis, MN, USA). Anti-mouse IgM monoclonal antibody was obtained from Jackson Immuno Research (West Grove, PA, USA). Z-VRPR-FMK (75 μM; AdipoGen Life Sciences, Liestal, Switzerland) was dissolved in dimethyl sulfoxide and added to cells 30 min before stimulation.