A REGULATORY ROLE FOR TRAF1 IN ANTIGEN-INDUCED APOPTOSIS OF T-CELLS

Tumor necrosis factor receptor (TNFR)-associated factor 2 (TRAF2) and TRAF1 were found as components of the TNFR2 signaling complex, which e xerts multiple biological effects on cells such as cell proliferation, cytokine production, and cell death. In the TNFR2-mediated. signaling pathways, TRAF2 works as a mediator for activation signals such as NF -KB, but the role of TRAF1 has not been previously determined. Here we show in transgenic mice that TRAF1 overexpression inhibits antigen-in duced apoptosis of CD8(+) T lymphocytes. Our results demonstrate a bio logical role for TRAF1 as a regulator of apoptotic signals and also su pport tile hypothesis that the combination of TRAF proteins in a given cell type determines distinct biological effects triggered by members of tile TNF receptor superfamily.