T-cell apoptosis in inflammatory brain lesions: destruction of T cells does not depend on antigen recognition.
Elimination of inflammatory T cells by apoptosis appears to play an important role in the down-regulation of inflammation in the central nervous system. Here we report that apoptosis of T lymphocytes occurs to a similar extent in different models of autoimmune encephalomyelitis. Apoptosis is restricted to cells located in the neuroectodermal parenchyma, thereby leaving T cells present in the brain's connective tissue compartments unharmed. Death of T cells in the parenchyma does not depend on antigen presentation by resident microglial cells or astrocytes. Adoptive transfer experiments with T lymphocytes carrying a specific genetic marker revealed that in the central nervous system these cells are destroyed regardless of their antigen specificity or state of activation. Although many of both antigen-dependent and -independent mechanisms in the induction of T-cell apoptosis may act simultaneously, our results suggest that the nervous system harbors a specific, currently undefined, mechanism that effectively eliminates infiltrating T lymphocytes.
Bauer
J
J
Institute of Neurology, University of Vienna, Austria.
Bradl
M
M
Hickley
W F
WF
Forss-Petter
S
S
Breitschopf
H
H
Linington
C
C
Wekerle
H
H
Lassmann
H
H
D000818:Animals; D030801:Animals, Genetically Modified; D017951:Antigen Presentation / Q000276:immunology*; D017209:Apoptosis / Q000276:immunology*; D001921:Brain / Q000276:immunology / Q000473:pathology; D002452:Cell Count; D016923:Cell Death; D002465:Cell Movement / Q000276:immunology; D004681:Encephalomyelitis, Autoimmune, Experimental / Q000276:immunology* / Q000473:pathology; D007124:Immunoenzyme Techniques; D004676:Myelin Basic Protein / Q000276:immunology; D051381:Rats; D011917:Rats, Inbred Lew; D013116:Spinal Cord / Q000276:immunology / Q000473:pathology; D013601:T-Lymphocytes / Q000276:immunology* / Q000473:pathology
D004676:Myelin Basic Protein