title: Tissue exit: a novel control point in the accumulation of antigen-specific CD8 T cells in the influenza a virus-infected lung.
abstract: Memory/effector T cells efficiently migrate into extralymphoid tissues and sites of infection, providing immunosurveillance and a first line of defense against invading pathogens. Even though it is a potential means to regulate the size, quality, and duration of a tissue infiltrate, T cell egress from infected tissues is poorly understood. Using a mouse model of influenza A virus infection, we found that CD8 effector T cells egressed from the infected lung in a CCR7-dependent manner. In contrast, following antigen recognition, effector CD8 T cell egress decreased and CCR7 function was reduced in vivo and in vitro, indicating that the exit of CD8 T cells from infected tissues is tightly regulated. Our data suggest that the regulation of T cell egress is a mechanism to retain antigen-specific effectors at the site of infection to promote viral clearance, while decreasing the numbers of bystander T cells and preventing overt inflammation.
authors.affiliation: Department of Pathobiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA.
authors.forename: Silke
authors.initials: S
authors.lastname: Jennrich
authors.forename: Michael H
authors.initials: MH
authors.lastname: Lee
authors.forename: Rachel C
authors.initials: RC
authors.lastname: Lynn
authors.forename: Kristofer
authors.initials: K
authors.lastname: Dewberry
authors.forename: Gudrun F
authors.initials: GF
authors.lastname: Debes
mesh_terms: D000818:Animals; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology* / Q000821:virology; D005260:Female; D006801:Humans; D009980:Influenza A virus / Q000235:genetics / Q000276:immunology* / Q000502:physiology; D007251:Influenza, Human / Q000276:immunology* / Q000821:virology; D008168:Lung / Q000276:immunology* / Q000821:virology; D051379:Mice; D008807:Mice, Inbred BALB C; D018345:Mice, Knockout; D054400:Receptors, CCR7 / Q000235:genetics / Q000276:immunology
chemical_list: C515371:Ccr7 protein, mouse; D054400:Receptors, CCR7