title: Primary infection of C57BL/6 mice with Plasmodium yoelii induces a heterogeneous response of NKT cells.
abstract: NKT cells are a population of innate-like lymphocytes that display effector functions and immunoregulatory properties. We characterized the NKT cell response induced in C57BL/6 mice during a primary infection with Plasmodium yoelii sporozoites. We observed a heterogeneous NKT cell response that differed between liver and spleen. Hepatic NKT cells found in infected livers consisted mainly of CD1d-dependent CD4+ and double-negative (DN) NKT cells, whereas CD1d-independent NKT cells exhibiting a TCR(high) CD4(high) phenotype were prominent among splenic NKT cells during the infection. Hepatic and splenic NKT cells isolated from infected mice were activated and secreted mainly gamma interferon and tumor necrosis factor alpha in response to stimulation. Finally, P. yoelii-activated hepatic DN NKT cells inhibited the parasite's liver stage in a CD1d-dependent manner in vitro. However, experiments using B6.CD1d-deficient mice showed that CD1d and CD1d-restricted NKT cells are not necessary to control the parasite's development in vivo during neither the preerythrocytic stage nor the erythrocytic stage. Thus, our results show that a primary P. yoelii infection induces a heterogeneous and organ-specific response of NKT cells and that CD1d-dependent NKT cells play a minor role in the control of the development of Plasmodium in vivo in our model.
authors.affiliation: Unité d'Immunophysiopathologie Infectieuse, Institut Pasteur, 25-28 rue du Docteur Roux, 75724 Paris Cedex 15, France.
authors.forename: Valérie
authors.initials: V
authors.lastname: Soulard
authors.forename: Jacques
authors.initials: J
authors.lastname: Roland
authors.forename: Christèle
authors.initials: C
authors.lastname: Sellier
authors.forename: Anne Charlotte
authors.initials: AC
authors.lastname: Gruner
authors.forename: Maria
authors.initials: M
authors.lastname: Leite-de-Moraes
authors.forename: Jean-François
authors.initials: JF
authors.lastname: Franetich
authors.forename: Laurent
authors.initials: L
authors.lastname: Rénia
authors.forename: Pierre-André
authors.initials: PA
authors.lastname: Cazenave
authors.forename: Sylviane
authors.initials: S
authors.lastname: Pied
mesh_terms: D000818:Animals; D018949:Antigens, CD1 / Q000235:genetics; D015704:CD4 Antigens / Q000378:metabolism; D005260:Female; D007694:Killer Cells, Natural / Q000276:immunology*; D008099:Liver / Q000276:immunology / Q000469:parasitology; D008288:Malaria / Q000276:immunology* / Q000469:parasitology; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D009928:Organ Specificity; D010967:Plasmodium yoelii / Q000254:growth & development / Q000472:pathogenicity*; D013154:Spleen / Q000276:immunology / Q000469:parasitology; D034101:Sporozoites
chemical_list: D018949:Antigens, CD1; D015704:CD4 Antigens