Hertzenberg Deetje 1 , Betz Martina 1 , Lehmann-Horn Klaus 1 , Zamvil Scott 2 , Lalive Patrice 3 , Hemmer Bernhard 1 , Weber Martin ⁎ ,1 1 Technische Universitaet Muenchen, Munich, Germany; 2 University of California, San Francisco, San Francisco, United States; 3 University of Geneva, Geneva, Switzerland B cells may have a dual role in the pathogenesis of multiple sclerosis (MS) serving as source for antibody-secreting plasma cells as well as acting as antigen presenting cells (APC) for activation of selfreactive T-cells.