Representative wells of a tumor IFN-γ ELISPOT assay. Pre- and postvaccine PBMC (1 × 105 cells/well) were co-cultured with sCD40Lt activated autologous tumor cells (2 × 105 cells/well) for 48 h as described in Materials and Methods. Wells containing PBMC alone and tumor cells alone served as controls. Samples were tested blinded in triplicates. Images from the plate scan generated by the ImmunoSpot analyzing system are shown. Average numbers of spots per well are indicated. Data is from a representative experiment of nine with similar results.