Tumor-specific cytolysis by peripheral blood lymphocytes derived from patient D12 before and after a repeat series of Id-KLH vaccinations (third course of vaccinations).

Prevaccine and postvaccine PBMC effectors were restimulated using 2 weekly cycles of CD40L-activated autologous tumor cells plus interleukin-2. After 14 days, the ability of effectors to lyse unmodified, cryopreserved tumor cells was assessed in a 4-hour⁵¹Cr release assay. Purified autologous normal peripheral blood B cells serve as negative control targets. The percentage specific lysis is expressed as the mean of triplicate values. Results are representative of 3 independent experiments. ▴ indicates postvaccine course no. 3 versus tumor targets; ▵ indicates prevaccine course no. 3 versus tumor targets; ● indicates postvaccine course no. 3 versus normal B cells; and ○ indicates prevaccine course no. 3 versus normal B cells.