title: Impact of CCR7 on priming and distribution of antiviral effector and memory CTL.
abstract: The chemokine receptor CCR7 is a key factor in the coordinate migration of T cells and dendritic cells (DC) into and their localization within secondary lymphoid organs. In this study we investigated the impact of CCR7 on CD8(+) T cell responses by infecting CCR7(-/-) mice with lymphocytic choriomeningitis virus (LCMV). We found that the absence of CCR7 affects the magnitude of an antiviral CTL response during the acute phase, with reduced numbers of virus-specific CTL in all lymphoid and nonlymphoid organs tested. On the single cell level, CCR7-deficient CTL gained full effector function, such that antiviral protection in CCR7-deficient mice was complete, but delayed. Similarly, adoptive transfer experiments using DC from CCR7-deficient or competent mice for the priming of CCR7-positive or CCR7-negative CD8(+) T cells, respectively, revealed that ectopic positioning of DC and CTL outside organized T cell zones results in reduced priming efficacy. In the memory phase, CCR7-deficient mice maintained a stable LCMV-specific CTL population, predominantly in nonlymphoid organs, and rapidly mounted protective CTL responses against a challenge infection with a vaccinia virus recombinant for the gp33 epitope of LCMV. Taken together, the CCR7-dependent organization of the T cell zone does not appear to be a prerequisite for antiviral effector CTL differentiation and the sustenance of antiviral memory responses in lymphoid or peripheral tissues.
authors.affiliation: Institute of Experimental Immunology, Zurich, Switzerland. tobias.junt@usz.ch
authors.forename: Tobias
authors.initials: T
authors.lastname: Junt
authors.forename: Elke
authors.initials: E
authors.lastname: Scandella
authors.forename: Reinhold
authors.initials: R
authors.lastname: Förster
authors.forename: Philippe
authors.initials: P
authors.lastname: Krebs
authors.forename: Stefan
authors.initials: S
authors.lastname: Krautwald
authors.forename: Martin
authors.initials: M
authors.lastname: Lipp
authors.forename: Hans
authors.initials: H
authors.lastname: Hengartner
authors.forename: Burkhard
authors.initials: B
authors.lastname: Ludewig
mesh_terms: D019264:Adoptive Transfer; D000818:Animals; D002465:Cell Movement / Q000235:genetics / Q000276:immunology; D017637:Clonal Deletion / Q000235:genetics; D003602:Cytotoxicity, Immunologic / Q000235:genetics; D003713:Dendritic Cells / Q000276:immunology / Q000378:metabolism / Q000821:virology; D007117:Immunization, Secondary; D007156:Immunologic Memory / Q000235:genetics; D007700:Kinetics; D019041:L-Selectin / Q000096:biosynthesis; D008213:Lymphocyte Activation / Q000235:genetics / Q000276:immunology*; D008216:Lymphocytic Choriomeningitis / Q000235:genetics / Q000276:immunology / Q000517:prevention & control; D008217:Lymphocytic choriomeningitis virus / Q000276:immunology*; D008221:Lymphoid Tissue / Q000276:immunology / Q000473:pathology / Q000821:virology; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D008822:Mice, Transgenic; D009928:Organ Specificity / Q000235:genetics / Q000276:immunology; D054400:Receptors, CCR7; D019707:Receptors, Chemokine / Q000096:biosynthesis / Q000172:deficiency / Q000235:genetics / Q000502:physiology*; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology* / Q000378:metabolism / Q000637:transplantation / Q000821:virology*; D050378:T-Lymphocytes, Regulatory / Q000276:immunology / Q000378:metabolism / Q000821:virology
chemical_list: C515371:Ccr7 protein, mouse; D054400:Receptors, CCR7; D019707:Receptors, Chemokine; D019041:L-Selectin