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

cDNA expression library immunization (cDELI), based on the use of a large n umber of pathogen's cDNA clones, has been previously used in our laboratory in an experimental model of murine Taenia crassiceps cysticercosis. In thi s study we show that ex vivo immunization of mice with macrophages pulsed i n vitro with plasmid DNA containing cDNA expression library (2 x 10(4) clon es) 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 eff icacy 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 wit h large genomes and complicated life cycles. (C) 1999 Published by Elsevier Science Ltd. All rights reserved.