First Author | Sun M | Year | 2006 |
Journal | J Immunol | Volume | 177 |
Issue | 3 | Pages | 1481-91 |
PubMed ID | 16849454 | Mgi Jnum | J:138030 |
Mgi Id | MGI:3803566 | Doi | 10.4049/jimmunol.177.3.1481 |
Citation | Sun M, et al. (2006) The cytoplasmic domain of Fas ligand costimulates TCR signals. J Immunol 177(3):1481-91 |
abstractText | Productive T cell activation generally requires costimulation in addition to a signal delivered through the TCR. Although FasL is well-characterized for its capacity to deliver a death signal through Fas, this TNF family member can also transmit a reverse signal to enhance Ag-driven T cell proliferation. In this study, we define this reverse signal through FasL as costimulation by showing it requires TCR coengagement and is CD28 independent. We demonstrate that FasL-mediated costimulation drives FasL recruitment into lipid rafts and association with select Src homology 3 (SH3)-containing proteins. We further show that the proline-rich intracellular domain of FasL is sufficient to costimulate by enhancing the phosphorylation of Akt, ERK1/2, JNK, and FasL itself, by activating the transcription factors NFAT and AP-1, and by enhancing IFN-gamma production. These results elucidate the pathway of costimulation through the death inducer FasL, and comprise the first mechanistic analysis of a newly emerging group of costimulators, the TNF family. |