CD19 and agammaglobulinemia: 34 Van Zelm Van Zelm MC MC Smet Smet J J Adams Adams B B Mascart Mascart F F Schandene Schandene L L Janssen Janssen F F CD81 gene defect in humans disrupts CD19 complex formation and leads to antibody deficiency CD81 gene defect in humans disrupts CD19 complex formation and leads to antibody deficiency J Clin Invest.