Time-dependent and cell-specific effects of anti-B4–bR and anti-B4 on intracellular calcium mobilization. Namalwa, Daudi, and Molt-4 cells were loaded with the Ca2+ indicator Fluo-3-AM and then stimulated with a concentration of 5 nmol/L of unconjugated anti-B4 MoAb (anti-CD19), or anti-B4–bR (anti-CD19-bR) followed by GAM. In some experiments, Molt-4 cells were stimulated with ionomycin (3 μmol/L). Agents were added at 125 seconds as indicated by the arrows, and fluorescence was measured every second with no interruption of sample flow during the data collection period (from 0 to 512 seconds). Data are expressed as dot plots of fluorescence versus time. Traces are representative of eight, five, and two separate experiments with Namalwa, Daudi, and Molt-4 cells, respectively.
