title: Efficient in vivo priming of specific cytotoxic T cell responses by neonatal dendritic cells.
abstract: In early life, a high susceptibility to infectious diseases as well as a poor capacity to respond to vaccines are generally observed as compared with observations in adults. The mechanisms underlying immune immaturity have not been fully elucidated and could be due to the immaturity of the T/B cell responses and/or to a defect in the nature and quality of Ag presentation by the APC. This prompted us to phenotypically and functionally characterize early life murine dendritic cells (DC) purified from spleens of 7-day-old mice. We showed that neonatal CD11c(+) DC express levels of costimulatory molecules and MHC molecules similar to those of adult DC and are able to fully maturate after LPS activation. Furthermore, we demonstrated that neonatal DC can efficiently take up, process, and present Ag to T cells in vitro and induce specific CTL responses in vivo. Although a reduced number of these cells was observed in the spleen of neonatal mice as compared with adults, this study clearly shows that neonatal DC have full functional capacity and may well prime Ag-specific naive T cells in vivo.
authors.affiliation: Unit of Biology of Immune Regulations, Institut Pasteur, 28 Rue du Dr Roux, 75724 Paris Cedex 15, France. gdadag@pasteur.fr
authors.forename: Gilles
authors.initials: G
authors.lastname: Dadaglio
authors.forename: Cheng-Ming
authors.initials: CM
authors.lastname: Sun
authors.forename: Richard
authors.initials: R
authors.lastname: Lo-Man
authors.forename: Claire Anne
authors.initials: CA
authors.lastname: Siegrist
authors.forename: Claude
authors.initials: C
authors.lastname: Leclerc
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D017951:Antigen Presentation; D000941:Antigens / Q000378:metabolism; D002454:Cell Differentiation; D002478:Cells, Cultured; D003601:Cytotoxicity Tests, Immunologic; D003713:Dendritic Cells / Q000145:classification / Q000187:drug effects / Q000276:immunology*; D004705:Endocytosis; D006825:Hybridomas; D016130:Immunophenotyping; D016167:Integrin alphaXbeta2 / Q000032:analysis; D008070:Lipopolysaccharides / Q000494:pharmacology; D007959:Lymphocyte Culture Test, Mixed; D051379:Mice; D008807:Mice, Inbred BALB C; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology*
chemical_list: D000941:Antigens; D016167:Integrin alphaXbeta2; D008070:Lipopolysaccharides