Effects of interferon inducible protein 16 (IFI16) on viral protein and pro-inflammatory cytokine ex-pression in human T-cell leukemia virus type 1 (HTLV-1)-positive T cells / 中华微生物学和免疫学杂志

ABSTRACT

Objective To investigate the effects of interferon inducible protein 16 (IFI16), a cy-tosolic DNA sensor, on the expression of human T-cell leukemia virus type 1 (HTLV-1) proteins and pro-in-flammatory cytokines in adult HTLV-1-positive T cells. Methods IFI16 expression in different HTLV-1-positive T cell lines was detected by immunoblot assay. Specific siRNA targeting the IFI16 gene was con-structed and the gene silencing efficiency was detected by immunoblot assay. Expression of HTLV-1 Tax pro-tein at mRNA and protein levels was respectively detected by real-time PCR and immunoblot assay after knocking down the expression of IFI16 in HTLV-1-positive T cells with siRNA. Expression of interferon ( IFN)-α, IFN-γ, tumor necrosis factor ( TNF )-α, Tax and Env were detected by real-time PCR. Re-sults Compared with the HTLV-1-negative T cell line Jurkat, IFI16 expression was enhanced in the HTLV-1-positive T cell lines MT2, MT4 and C8166. Tax expression was increased, while that of IFN-α, IFN-γand TNF-α was decreased in MT2 and MT4 cells after silencing the expression of IFI16 with siRNA. Con-clusions IFI16 expression was increased in HTLV-1-positive MT2 and MT4 cells. Meanwhile, IFI16 pro-moted the production of interferon and pro-inflammatory cytokines and inhibited the expression of HTLV-1 proteins.