%0 Journal Article
%T In Vivo Identification and Characterization of CD4+ Cytotoxic T Cells Induced by Virulent Brucella abortus Infection
%A Anna Martirosyan
%A Kristine Von Bargen
%A Vilma Arce Gorvel
%A Weidong Zhao
%A Sean Hanniffy
%A Johnny Bonnardel
%A St¨¦phane M¨¦resse
%A Jean-Pierre Gorvel
%J PLOS ONE
%D 2013
%I Public Library of Science (PLoS)
%R 10.1371/journal.pone.0082508
%X 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-¦Ã. 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-¦Ã and granzyme B expression. CD4+ CTLs represent a so far uncharacterized immune cell sub-type triggered by early immune responses upon Brucella abortus infection.
%U http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0082508