Soluble TNF-alpha but not transmembrane TNF-alpha sensitizes T cells for enhanced activation-induced cell death.
Eur J Immunol
; 39(11): 3171-80, 2009 Nov.
Article
en En
| MEDLINE
| ID: mdl-19681056
In addition to its proinflammatory effects, TNF-alpha exhibits immunosuppression. Here, we compared the capacities of transmembrane TNF-alpha (tmTNF) and soluble TNF-alpha (sTNF) in regulating expansion of activated T cells by apoptosis. Splenic CD4(+) T cells from wtTNF, TNF-alpha-deficient (TNF(-/-)) and TNF(-/-) mice expressing a non-cleavable mutant tmTNF showed comparable proliferation rates upon TCR-mediated stimulation. Activation-induced cell death (AICD), however, was significantly attenuated in tmTNF and TNF(-/-), compared with wtTNF CD4(+) T cells. Addition of sTNF during initial priming was sufficient to enhance susceptibility to AICD in tmTNF and TNF(-/-) CD4(+) T cells to levels seen in wtTNF CD4(+) T cells, whereas addition of sTNF only during restimulation failed to enhance AICD. sTNF-induced, enhanced susceptibility to AICD was dependent on both TNF receptors. The reduced susceptibility of tmTNF CD4(+) T cells for AICD was also evident in an in vivo model of adoptively transferred CD4(+) T-cell-mediated colonic inflammation. Hence, the presence of sTNF during T-cell priming may represent an important mechanism to sensitize activated T cells for apoptosis, thereby attenuating the extent and duration of T-cell reactivities and subsequent T-cell-mediated, excessive inflammation.
Texto completo:
1
Colección:
01-internacional
Banco de datos:
MEDLINE
Asunto principal:
Activación de Linfocitos
/
Linfocitos T
/
Factor de Necrosis Tumoral alfa
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Apoptosis
/
Inmunomodulación
Tipo de estudio:
Prognostic_studies
Límite:
Animals
Idioma:
En
Revista:
Eur J Immunol
Año:
2009
Tipo del documento:
Article
País de afiliación:
Suiza