Resumen
TRAIL (TNF-related apoptosis inducing ligand), like other members of the TNF family of proteins, is able to induce apoptosis in sensitive target cells. Recently, cell-surface TRAIL has been shown to be expressed by activated human and mouse T lymphocytes, raising the possibility that TRAIL might be involved in T cell-mediated cytotoxicity and/or immune regulation. In the present study we show by semiquantitative reverse transcriptase polymerase chain reaction (RT-PCR) analysis that activated, but not resting, mouse T cells express abundant TRAIL mRNA. TRAIL transcripts were detectable within 4 h of T cell activation. A panel of pharmacologic inhibitors was used to investigate the signal transduction pathways involved in TRAIL gene induction following T lymphocyte activation. Trail gene expression was sensitive to the src-like protein tyrosine kinase (PTK) inhibitor herbimycin A, as well as the more general PTK inhibitor genistein, suggesting the involvement of a src family PTK. The PKC inhibitors staurosporine and calphostin C, and the phosphatidylinositol 3-kinase (PI3-K) inhibitors wortmannin and LY294002, also prevented TRAIL mRNA transcription by activated T cells, indicating a role for PKC and PI3-K. In addition, TRAIL induction was inhibited by cyclosporin A, implicating the Ca2+/calmodulin-dependent protein phosphatase calcineurin. TRAIL expression was also blocked by rapamycin, which inhibits p70 S6 kinase involved in CD28 and interleukin (IL)-2 receptor signaling. However, TRAIL mRNA expression was not induced by IL-2, suggesting that TRAIL gene induction is not coupled to the IL-2 receptor. Data obtained by RT-PCR were confirmed at the protein level by immunoblotting with TRAIL-specific antibody. We conclude that TRAIL gene induction is initiated through a T cell receptor-associated signaling pathway similar to that responsible for the expression of cytokine genes such as IL- 2.
Idioma original | English |
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Páginas (desde-hasta) | 96-103 |
Número de páginas | 8 |
Publicación | Experimental Cell Research |
Volumen | 252 |
N.º | 1 |
DOI | |
Estado | Published - oct. 10 1999 |
Nota bibliográfica
Funding Information:This work was supported by a grant to D.H. from the Natural Sciences and Engineering Research Council of Canada (OGP0046295). B.M. and A.M. are recipients of NSERC Postgraduate Studentships. J.B. was supported by a CaRE (Cancer Research and Education) Nova Scotia Trainee Award with funding from the Faculty of Medicine, Dalhousie University.
ASJC Scopus Subject Areas
- Cell Biology
PubMed: MeSH publication types
- Journal Article
- Research Support, Non-U.S. Gov't