Homotypic aggregation of the BaF3 cell transfectants upon addition of anti-CD34 MoAb QBEND 10. BaF3-CD34 cells were incubated with the negative control MoAb (A) or anti-CD34 MoAb QBEND 10 (B), which represents the typical morphology of homoaggregate formation of BaF3-CD34 cells (score, 3+). Similarly, BaF3-CD34/T cells (C), BaF3-CD34/EPOR cells (D), and BaF3-CD34/G-CSFR cells (E) were treated with MoAb QBEND 10. As a positive control, KG1a cells were also incubated with MoAb QBEND 10 (F). The final concentration of MoAb is 5 μg/mL. This experiment has been repeated five times with similar results.