Send to

Choose Destination
J Immunol. 2004 May 15;172(10):6313-23.

Viral FLIP impairs survival of activated T cells and generation of CD8+ T cell memory.

Author information

Immunoregulation Unit, Autoimmunity Branch, National Institute of Arthritis and Musculoskeletal and Skin Diseases, National Institutes of Health, Bethesda, MD 20892, USA.


Viral FLIPs (vFLIPs) interfere with apoptosis signaling by death-domain-containing receptors in the TNFR superfamily (death receptors). In this study, we show that T cell-specific transgenic expression of MC159-vFLIP from the human Molluscum contagiosum virus blocks CD95-induced apoptosis in thymocytes and peripheral T cells, but also impairs postactivation survival of in vitro activated primary T cells despite normal early activation parameters. MC159 vFLIP impairs T cell development to a lesser extent than does Fas-associated death domain protein deficiency or another viral FLIP, E8. In the periphery, vFLIP expression leads to a specific deficit of functional memory CD8(+) T cells. After immunization with a protein Ag, Ag-specific CD8(+) T cells initially proliferate, but quickly disappear and fail to produce Ag-specific memory CD8(+) T cells. Viral FLIP transgenic mice exhibit impaired CD8(+) T cell responses to lymphocytic choriomeningitis virus and Trypanosoma cruzi infections, and a specific defect in CD8(+) T cell recall responses to influenza virus was seen. These results suggest that vFLIP expression in T cells blocks signals necessary for the sustained survival of CD8(+) T cells and the generation of CD8(+) T cell memory. Through this mechanism, vFLIP proteins expressed by T cell tropic viruses may impair the CD8(+) T cell immune responses directed against them.

[Indexed for MEDLINE]
Free full text

LinkOut - more resources

Full Text Sources

Other Literature Sources


Supplemental Content

Full text links

Icon for HighWire
Loading ...
Support Center