Cell death in vasculitic neuropathy.
Vasculitic neuropathy shows cluster of differentiation (CD)4+ and CD8+ perivascular infiltrates. CD8+ cells kill the target by different ways. Some mechanisms require the release of granzymes and T-cell restricted intracellular antigen (TIA-1) which induce cell death by apoptosis. A nonsecretory ligand-mediated mechanism has been proposed for apoptosis and requires the interaction of Fas and Fas-ligand. We studied apoptosis by immunohistochemistry and terminal deoxynucleotidyl transferase-mediated nick end labeling (TUNEL) in nerve biopsy specimens in 19 cases of vasculitic neuropathy and 8 controls. In vasculitic neuropathy, perivascular mononuclear cells expressed TIA-1, granzyme A, and granzyme B. Regarding the ligand-mediated mechanism, we observed Fas+ and Fas-ligand+ mononuclear cells in an epineurial-perivascular distribution. Cells undergoing apoptosis, as demonstrated by TUNEL, represented mononuclear cells. In vasculitic neuropathy, apoptosis by both a secretory and a nonsecretory mechanism is suspected. However, apoptosis seems to be restricted to inflammatory mononuclear cells, suggesting that it may play a critical role in recovery from vasculitic neuropathy.
Heuss
D
D
Department of Neurology, Friedrich Alexander University of Erlangen-Nürnberg, Schwabachanlage 6, D-91054 Erlangen, Germany. dieter.heuss@neuro.med.uni-erlangen.de
Probst-Cousin
S
S
Kayser
C
C
Neundörfer
B
B
D017209:Apoptosis / Q000502:physiology; D016923:Cell Death / Q000502:physiology; D006801:Humans; D007150:Immunohistochemistry; D020287:In Situ Nick-End Labeling; D009410:Nerve Degeneration / Q000473:pathology; D010523:Peripheral Nervous System Diseases / Q000276:immunology / Q000473:pathology*; D013497:Sural Nerve / Q000473:pathology; D014657:Vasculitis / Q000276:immunology / Q000473:pathology*