Human B cell isolation and cultures
Venous peripheral blood was withdrawn from each patient and healthy
control subject. B cells were isolated by positive selection using CD19
beads, according to the manufacturer’s instructions (Miltenyi, Bergisch
Gladbach, Germany; routine purity > 95%). Cell culture was
performed in human B cell culture medium (Lonza, Walkersville, MD, USA)
supplemented with 10% foetal bovine serum (FBS) and 1%
penicillin/streptomycin.