DNA pulsed macrophage-mediated cDNA expression library immunization in vaccine development.

cDNA expression library immunization (cDELI), based on the use of a large number of pathogen's cDNA clones, has been previously used in our laboratory in an experimental model of murine Taenia crassiceps cysticercosis. In this study we show that ex vivo immunization of mice with macrophages pulsed in vitro with plasmid DNA containing cDNA expression library (2x10(4) clones) leads to significant reduction of parasite load. Additionally, pathogen-specific proliferation of splenocytes from immunized mice is demonstrated indicating the induction of cellular protective immune response and the efficacy of the proposed strategy to identify vaccine candidate antigens. Our method may represent an attractive tool in vaccine discovery applicable to any host-pathogen system and may be useful especially for the pathogens with large genomes and complicated life cycles.