Behavior of parasite-specific effector CD8+ T cells in the brain and visualization of a kinesis-associated system of reticular fibers.
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.
Wilson
Emma H
EH
Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA. emmaw@ucr.edu
Harris
Tajie H
TH
Mrass
Paulus
P
John
Beena
B
Tait
Elia D
ED
Wu
Gregory F
GF
Pepper
Marion
M
Wherry
E John
EJ
Dzierzinski
Florence
F
Roos
David
D
Haydon
Philip G
PG
Laufer
Terri M
TM
Weninger
Wolfgang
W
Hunter
Christopher A
CA
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