Flow cytometric analysis of tumor-specific cell staining by sera from patients vaccinated with Id-KLH–pulsed dendritic cells.

Tumor cells from patients D31 and D29 (upper and lower sets of panels, respectively) were incubated with autologous postvaccine serum or that of the other patient as a control. Bound anti-Id IgG antibodies were detected by anti-IgG-PE (y-axis), and tumor B cells (IgM+) were counterstained by anti-IgM–FITC (x-axis). Each patient's serum specifically recognizes only the autologous tumor cells but not the control, irrelevant tumor cells.