title: Behavior of parasite-specific effector CD8+ T cells in the brain and visualization of a kinesis-associated system of reticular fibers.
abstract: To understand lymphocyte behavior in the brain, we used two-photon microscopy to visualize effector CD8(+) T cells during toxoplasmic encephalitis. These cells displayed multiple behaviors with two distinct populations of cells apparent: one with a constrained pattern of migration and one with a highly migratory subset. The proportion of these populations varied over time associated with changes in antigen availability as well as T cell expression of the inhibitory receptor PD1. Unexpectedly, the movement of infiltrating cells was closely associated with an infection-induced reticular system of fibers. This observation suggests that, whereas in other tissues pre-existing scaffolds exist that guide lymphocyte migration, in the brain specialized structures are induced by inflammation that guide migration of T cells in this immune-privileged environment.
authors.affiliation: Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA. emmaw@ucr.edu
authors.forename: Emma H
authors.initials: EH
authors.lastname: Wilson
authors.forename: Tajie H
authors.initials: TH
authors.lastname: Harris
authors.forename: Paulus
authors.initials: P
authors.lastname: Mrass
authors.forename: Beena
authors.initials: B
authors.lastname: John
authors.forename: Elia D
authors.initials: ED
authors.lastname: Tait
authors.forename: Gregory F
authors.initials: GF
authors.lastname: Wu
authors.forename: Marion
authors.initials: M
authors.lastname: Pepper
authors.forename: E John
authors.initials: EJ
authors.lastname: Wherry
authors.forename: Florence
authors.initials: F
authors.lastname: Dzierzinski
authors.forename: David
authors.initials: D
authors.lastname: Roos
authors.forename: Philip G
authors.initials: PG
authors.lastname: Haydon
authors.forename: Terri M
authors.initials: TM
authors.lastname: Laufer
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Weninger
authors.forename: Christopher A
authors.initials: CA
authors.lastname: Hunter
mesh_terms: D000818:Animals; D018414:CD8-Positive T-Lymphocytes / Q000166:cytology* / Q000276:immunology*; D002465:Cell Movement / Q000276:immunology*; D002490:Central Nervous System / Q000276:immunology; D051379:Mice; D051381:Rats; D014122:Toxoplasma / Q000276:immunology*; D016781:Toxoplasmosis, Cerebral / Q000276:immunology* / Q000469:parasitology* / Q000473:pathology