RNA interference-mediated gene silencing in murine T cells: In vitro and in vivo validation of proinflammatory target genes

Abstract

Background: T cells play a central role in many inflammatory diseases, hence the identification and validation of T cell-specific target genes will increase the understanding of T cell function in pathologic inflammatory situations. RNA interference (RNAi), with its ability to induce specific gene silencing in mammalian cells, represents a powerful technology to investigate and validate the function of pharmaceutical target genes in vitro and in vivo. The aim of the present study was to systematically explore RNAi-mediated gene-silencing of known T cell-specific model signaling molecules in primary murine T cells in vitro and in vivo. Results: We demonstrate that siRNA delivery and subsequent silencing of T cell specific genes is substantially increased, if murine T cells were activated prior siRNA transfection. Silencing of ZAP70, p56Lck as well as PLC-a1 protein expression resulted in impaired function of T cells in vitro. Furthermore, delayed type hypersensitivity (DTH) was ameliorated in vivo after adoptive transfer of ZAP70-silenced T cells. Coclusion: The combination of RNAi-mediated gene silencing and adoptive transfer of genesilenced T cells, thus, may allow the identification and analysis of T cell-specific targets for therapeutic intervention. Additionally, this model system may represent an alternative to conventional time consuming and cost intensive gene targeting approaches. © 2008 Gust et al; licensee BioMed Central Ltd.