BACKGROUNDInterleukin 1beta (IL-1beta) is the principal mediator in the pathogenesis of rheumatoid arthritis. Continuous injection of interleukin 1beta (IL-1beta) into the knee articular cavities of animals can induce models that resemble rheumatoid arthritis. The objective of this study was to evaluate the feasibility of local recombinant retrovirus viral interleukin 10 (rRV-vIL-10) gene transfer treatment of a rabbit model of arthritis induced by IL-1beta.

METHODSAn hIL-1beta-induced rabbit rheumatoid arthritis model was established using the MFG-hIL-1beta-neo-HIG-82 cell line, which is capable of continuous secretion of hIL-1beta. After transfecting the rabbit synovial fibroblast cell line (MFG-hIL-1beta-neo-HIG-82) with rRV-vIL-10, G418 was then added to identify the positive clone. The rRV-vIL-10 positive clone was injected into the established rabbit rheumatoid arthritis model through intra-articular injection. Successful gene transfer was determined by reverse transcription-polymerase chain reaction (RT-PCR) and immunohistochemistry. The levels of IL-1beta before and after treatment were determined by enzyme- linked immunosorbent assay.

RESULTSRetrovirus vector was an effective vector both to synoviocytes in vitro and synovium tissue in vivo as confirmed by RT-PCR and immunohistochemistry. The rabbit arthritis model treated with rRV-vIL-10 showed a dramatic remission of arthritis and a decline in the level of cytokines such as IL-1beta.

CONCLUSIONSRetrovirus-mediated transfection of vIL-10 successfully transferred the gene into rabbit synovium ex vivo and was able to suppress intra-articular inflammation response to IL-1beta.