Figure 3
From: A modified human ELISPOT assay to detect specific responses to primary tumor cell targets
Incubation of PBMC and tumor cells for 48 h enhanced the sensitivity of the tumor IFN-γ ELISPOT assay. Pre- (white columns) and postvaccine (grey columns) PBMC (1 × 105 cells/well) were co-cultured with sCD40Lt activated autologous tumor cells (2 × 105 cells/well) for 24, 48 and 72 h in the ELISPOT assay. Significantly (p < 0.05) more IFN-γ production by responding T cells was observed in post- compared to prevaccine PBMC samples regardless of the length of incubation. Moreover, a significantly higher number of tumor-reactive T cells were observed at the 48 h in the postvaccine PBMC (p < 0.01). Data is represented as average number of spots per well ± SE (n = 3). Data for 72 h is not shown because the resulting spots were too numerous and/or diffuse to count accurately.