| First Author | Zhang Y | Year | 2005 |
| Journal | J Immunol | Volume | 175 |
| Issue | 5 | Pages | 3033-44 |
| PubMed ID | 16116191 | Mgi Jnum | J:113207 |
| Mgi Id | MGI:3664806 | Doi | 10.4049/jimmunol.175.5.3033 |
| Citation | Zhang Y, et al. (2005) Conditional Fas-associated death domain protein (FADD): GFP knockout mice reveal FADD is dispensable in thymic development but essential in peripheral T cell homeostasis. J Immunol 175(5):3033-44 |
| abstractText | Fas-associated death domain protein (FADD)/mediator of receptor-induced toxicity-1 is required for signaling induced by death receptors such as Fas. In earlier studies, FADD-deficient mice died in utero, and a FADD deficiency in embryonic stem cells inhibited T cell production in viable FADD-/- -->RAG-1-/- chimeras. To analyze the temporal requirement of FADD in the development and function in the T lineage, it is necessary to establish viable mutant mice producing detectable FADD-deficient T cells. We generated mice that express a functional FADD:GFP fusion gene reconstituting normal embryogenesis and lymphopoiesis in the absence of the endogenous FADD. Efficient T cell-specific deletion of FADD:GFP was achieved, as indicated by the presence of a high percentage of GFP-negative thymocytes and peripheral T cells in mice expressing Lck-Cre or CD4-Cre. Sorted GFP-negative thymocytes and peripheral T cells contained undetectable levels of FADD and were resistant to apoptosis induced by Fas, TNF, and TCR restimulation. These T cell-specific FADD-deficient mice contain normal thymocyte numbers, but fewer peripheral T cells. Purified peripheral FADD-deficient T cells failed to undergo extensive homeostatic expansion after adoptive transfer into lymphocyte-deficient hosts, and responded poorly to proliferation induced by ex vivo TCR stimulation. Furthermore, deletion of FADD in preactivated mature T cells using retrovirus-Cre resulted in no proliferation. These results demonstrate that FADD plays a dispensable role during thymocyte development, but is essential in maintaining peripheral T cell homeostasis and regulating both apoptotic and proliferation signals. |
