title: In vivo identification and characterization of CD4⁺ cytotoxic T cells induced by virulent Brucella abortus infection.
abstract: CD4(+) T cells display a variety of helper functions necessary for an efficient adaptive immune response against bacterial invaders. This work reports the in vivo identification and characterization of murine cytotoxic CD4(+) T cells (CD4(+) CTL) during Brucella abortus infection. These CD4(+) CTLs express granzyme B and exhibit immunophenotypic features consistent with fully differentiated T cells. They express CD25, CD44, CD62L ,CD43 molecules at their surface and produce IFN-γ. Moreover, these cells express neither the co-stimulatory molecule CD27 nor the memory T cell marker CD127. We show here that CD4(+) CTLs are capable of cytolytic action against Brucella-infected antigen presenting cells (APC) but not against Mycobacterium-infected APC. Cytotoxic CD4(+) T cell population appears at early stages of the infection concomitantly with high levels of IFN-γ and granzyme B expression. CD4(+) CTLs represent a so far uncharacterized immune cell sub-type triggered by early immune responses upon Brucella abortus infection.
authors.affiliation: Aix-Marseille University, CIML, 13288, Marseille, France ; CNRS, UMR 7280, 13288, Marseille, France ; INSERM, U631, 13288, Marseille, France.
authors.forename: Anna
authors.initials: A
authors.lastname: Martirosyan
authors.affiliation: Aix-Marseille University, CIML, 13288, Marseille, France ; CNRS, UMR 7280, 13288, Marseille, France ; INSERM, U631, 13288, Marseille, France.
authors.forename: Kristine
authors.initials: K
authors.lastname: Von Bargen
authors.affiliation: Aix-Marseille University, CIML, 13288, Marseille, France ; CNRS, UMR 7280, 13288, Marseille, France ; INSERM, U631, 13288, Marseille, France.
authors.forename: Vilma
authors.initials: V
authors.lastname: Arce Gorvel
authors.affiliation: Aix-Marseille University, CIML, 13288, Marseille, France ; CNRS, UMR 7280, 13288, Marseille, France ; INSERM, U631, 13288, Marseille, France.
authors.forename: Weidong
authors.initials: W
authors.lastname: Zhao
authors.affiliation: Aix-Marseille University, CIML, 13288, Marseille, France ; CNRS, UMR 7280, 13288, Marseille, France ; INSERM, U631, 13288, Marseille, France.
authors.forename: Sean
authors.initials: S
authors.lastname: Hanniffy
authors.affiliation: Aix-Marseille University, CIML, 13288, Marseille, France ; CNRS, UMR 7280, 13288, Marseille, France ; INSERM, U631, 13288, Marseille, France.
authors.forename: Johnny
authors.initials: J
authors.lastname: Bonnardel
authors.affiliation: Aix-Marseille University, CIML, 13288, Marseille, France ; CNRS, UMR 7280, 13288, Marseille, France ; INSERM, U631, 13288, Marseille, France.
authors.forename: Stéphane
authors.initials: S
authors.lastname: Méresse
authors.affiliation: Aix-Marseille University, CIML, 13288, Marseille, France ; CNRS, UMR 7280, 13288, Marseille, France ; INSERM, U631, 13288, Marseille, France.
authors.forename: Jean-Pierre
authors.initials: JP
authors.lastname: Gorvel
mesh_terms: D000818:Animals; D002003:Brucella abortus / Q000276:immunology* / Q000472:pathogenicity*; D002006:Brucellosis / Q000276:immunology / Q000378:metabolism; D015496:CD4-Positive T-Lymphocytes / Q000378:metabolism*; D005260:Female; D005434:Flow Cytometry; D018960:Hyaluronan Receptors / Q000378:metabolism; D007371:Interferon-gamma / Q000378:metabolism; D053645:Interleukin-2 Receptor alpha Subunit / Q000378:metabolism; D019041:L-Selectin / Q000378:metabolism; D051917:Leukosialin / Q000378:metabolism; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D018613:Microscopy, Confocal; D013602:T-Lymphocytes, Cytotoxic / Q000378:metabolism*
chemical_list: D018960:Hyaluronan Receptors; D053645:Interleukin-2 Receptor alpha Subunit; D051917:Leukosialin; D019041:L-Selectin; D007371:Interferon-gamma