The anti-RP105 MoAb induces B cells to increase in cell size and expression of a costimulatory molecule CD80. Peripheral blood mononuclear cells were collected by Ficoll-Hypaque density gradient centrifugation and cultured in a 24-well plate at 2 × 106cells/well with or without the anti-MHR73 MoAb (20 μg/mL). After 24 hours (the left panel of A) or 40 hours (the right panel of A and B), cells were harvested and stained with FITC-labeled anti-CD19 MoAb and biotinylated anti-CD80 MoAb followed by avidin-phycoerythrin. Stained cells were analyzed on a FACScan. Only CD19+ B cells were examined, and profiles of forward scatter (A) or CD80 expression (B) are shown. Solid lines and hatched lines depict histograms of cells cultured with or without the MHR73 MoAb, respectively.
