| First Author | Tucek-Szabo CL | Year | 1996 |
| Journal | J Immunol | Volume | 156 |
| Issue | 1 | Pages | 192-200 |
| PubMed ID | 8598462 | Mgi Jnum | J:31074 |
| Mgi Id | MGI:78544 | Doi | 10.4049/jimmunol.156.1.192 |
| Citation | Tucek-Szabo CL, et al. (1996) Surface T cell Fas receptor/CD95 regulation, in vivo activation, and apoptosis. Activation-induced death can occur without Fas receptor. J Immunol 156(1):192-200 |
| abstractText | Fas-mediated apoptosis is a form of cell death that operates through a receptor-ligand interaction. The FasR has been implicated directly in peripheral T cell tolerance and activation-induced apoptosis of T cells in vitro, although to date its expression on murine peripheral T cells has been characterized incompletely, In this study, we document substantial expression of FasR on the vast majority of recent thymic emigrants and resting peripheral T lymphocytes. FasR ligation can induce death in a minor (similar to 5%) subset of these cells, By contrast to rather slow activation-mediated FasR up- regulation in vitro, we demonstrate that in vivo T cell activation by alpha CD3 mAb or superantigen results in rapid up-regulation of the FasR. This up-regulation is paralleled by the kinetics of activation-induced apoptosis in lymph node T cells, However, we demonstrate that the FasR is not necessary for activation-induced cell death, Lymph node T cells from young, healthy, FasR expression- deficient MRL-lpr/lpr animals could be activated in vivo through the TCR-CD3 complex. Most importantly, MRL-lpr/lpr T cells underwent massive activation-induced apoptosis in response to high and intermediate doses of alpha CD3. At a low alpha CDS dose, however, both MRL-lpr/lpr and MRL+/+ T cells were activated similarly, but only the latter underwent adequate apoptosis. Taken together, these findings suggest that in vivo, the Fas pathway may not be the only regulator of activation-induced T cell death, but that this pathway may be critical in regulating responses to weak stimuli. |
