title: Ontogeny and innate properties of neonatal dendritic cells.
abstract: We investigated whether a developmental immaturity of the dendritic cells (DCs) compartment could contribute to the high susceptibility to infections observed in newborns. DCs are among the first cells to colonize the spleen, but the ontogeny of DC subsets follows distinct steps. At birth, plasmacytoid DCs and CD4-CD8alpha- DCs are found in the spleen, whereas CD8alpha+ and CD4+ DCs are not present. Then, the CD8alpha+ DC compartment quickly develops and reaches an adult size by day 7, whereas the CD4+ DC compartment slowly increases to become predominant by the age of 3 weeks. The production of interleukin (IL)-12p70 by DCs is particularly efficient after birth, reflecting the stronger capacity of the neonatal CD8alpha- DCs to secrete IL-12 compared with its adult counterpart. Like-wise, neonatal DCs produced type I and II interferons. In vivo, following microbial stimulation, up-regulation of major histocompatibility complexes (MHCs) and of costimulatory molecules on DCs was induced clearly showing the activation of neonatal DCs in the neonatal environment. Therefore, despite a markedly different DC subset composition in early life compared with the adult DC compartment, neonatal DCs are fully competent in their innate immune functions.
authors.affiliation: Unité de Biologie des Régulations Immunitaires (Institut National de la Santé et de la Recherche Médicale E0352) Paris, France.
authors.forename: Cheng-Ming
authors.initials: CM
authors.lastname: Sun
authors.forename: Laurence
authors.initials: L
authors.lastname: Fiette
authors.forename: Myriam
authors.initials: M
authors.lastname: Tanguy
authors.forename: Claude
authors.initials: C
authors.lastname: Leclerc
authors.forename: Richard
authors.initials: R
authors.lastname: Lo-Man
mesh_terms: D000818:Animals; D000831:Animals, Newborn / Q000276:immunology*; D018845:CD11 Antigens / Q000032:analysis; D015704:CD4 Antigens / Q000032:analysis; D016827:CD8 Antigens / Q000032:analysis; D003713:Dendritic Cells / Q000276:immunology* / Q000378:metabolism; D004198:Disease Susceptibility; D005434:Flow Cytometry; D007107:Immune System / Q000254:growth & development*; D007121:Immunocompetence; D016130:Immunophenotyping; D007239:Infections / Q000209:etiology / Q000276:immunology; D018664:Interleukin-12 / Q000096:biosynthesis / Q000235:genetics; D008562:Membrane Glycoproteins / Q000032:analysis; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D011956:Receptors, Cell Surface / Q000032:analysis; D013154:Spleen / Q000254:growth & development / Q000276:immunology; D051193:Toll-Like Receptors
chemical_list: D018845:CD11 Antigens; D015704:CD4 Antigens; D016827:CD8 Antigens; C431698:CD8alpha antigen; D008562:Membrane Glycoproteins; D011956:Receptors, Cell Surface; D051193:Toll-Like Receptors; D018664:Interleukin-12