MBCD or after pre-treatment with 20 mM MBCD for 20min at 39uC prior to washing and adding the SVLP for 20min on ice. For reference, the cell control is shown as the solid grey histogram. The ‘‘Overlay’’ shows just the results with (coloured) and without (grey/black) MBCD. (B) As in (A), but using CTB in place of SVLP. (C) As in (A), but comparing a particular stock of SVLP used at 1 mg/ml and 10 mg/ml. (TIF) References 1. Wykes M, Pombo A, Jenkins C, MacPherson GG (1998) Dendritic cells interact directly with naive B lymphocytes to transfer antigen and initiate class switching in a primary T-dependent response. J Immunol 161: 1313–1319. 2. Lin ML, Zhan Y, Villadangos JA, Lew AM (2008) The cell biology of cross- presentation and the role of dendritic cell subsets. Immunol Cell Biol 86: 353– 362. 3. Banchereau J, Steinman RM (1998) Dendritic cells and the control of immunity. Nature 392: 245–252. 4. 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