Fig. 2.

Humoral and cellular responses raised after DNA vaccination with uP-PS/scFv6.C4. a CEA-specific AB3 antibodies from mice immunized with uP-PS/scFv6.C4 were detected by ELISA. Blood samples were collected 7 days after each immunization and diluted 1:100 for assays. Sera from mice immunized with uP vector were used as control. Arrows indicate day of immunization. Values for OD_490nm are expressed as mean ± SD of each group (n = 12 per group). Representative data of 2 biological replicate experiments are shown. ***p ≤ 0.001 and **p ≤ 0.01. b Immunocytochemistry of human colorectal adenocarcinoma cell lines, murine melanoma cell lines (B16F10 and B16F10-CEA) and murine colon tumor cell line (MC38) using sera from uP-PS/scFv6.C4-immunized mice. Sera from uP-immunized mice and pre-immune sera from uP-PS/scFv6.C4-immunized mice were used as negative control. Bar 100 µm. c CEA-specific CTL activity was determined using splenocytes isolated 7 days after the last immunization. B16F10-CEA, B16F10-scFv6.C4, and B16F10 cells were used as targets (target:effector ratio: 1:50). Data are expressed as mean ± SD of each group of mice (3 mice per group). Representative data of 2 biological replicate experiments are shown. ***p ≤ 0.001