Antitumor cross-reactivity of vaccine-induced Igs in responders. (A) Representative IHC evaluations of biotin-conjugated pre- (left) and postvaccination (right) Igs from responder 14 (i) and nonresponder 2 (ii) tested on allogeneic human FL specimens. Digital images were acquired with Nikon DN100 digital net camera and the Nikon Eclipse E400 microscope, and processed using Photoshop CS4 software version for Macintosh Pro personal computer. Original magnifications: panels, ×10; insets, ×40. (B) Flow cytometry of normal B (CD19) and T (CD3) cells, NHL cell lines (RL-19 and DOHH-2), and 4 different primary FLs (TM 1-4) using biotin-conjugated Igs from responders (top) and nonresponders (bottom) and FITC-labeled streptavidin as revealing system. Results are represented as the ratio between MFI of post- and prevaccination samples. Data are mean ± SE of 4 independent experiments. (C) WB analyses of DOHH-2 whole lysate probed with biotin-conjugated Igs purified from pre- (lanes 1) and post- (lanes 2) vaccination serum from responders 13, 14, 1, and 5 (left) and nonresponders 2, 8, and 17 (right). Arrow indicates the differentially revealed proteins. CR indicates complete responder; and PR, partial responder.