Relationship between the increase of secretion of sTNF_α induced by lipopolysaccharides and the enhanced expression of TACE mRNA in HL-60 cells and adhesive cells from human spleen

Abstract

In order to find out the potential modulators which influence the secretion of TNFα, the relationship between the amount of secreted TNFα(sTNFα) and the level of TNFα converting enzyme (TACE) gene expression was studied before and after the stimulation by lipopolysaccharides (LPS) to HL-60 cells and adhered cells isolated from human spleen using cytological and molecular biology techniques and methods (RT-PCR, Dot-blot hybridization, etc.). The experimental results showed that: (1) LPS could induce the increase of expression of TNFα mRNA and TACE mRNA, reaching the peak value at 6 h and 10 h respectively after addition of LPS into cell culture medium; (2) The anti-sense oligodeoxyribonucleotide (A-ODN) complementary to TACE mRNA sequence really inhibited the secretion of TNFα as a result of blocked translation of TACE gene; (3) Furthermore, it was also observed that RDQ, a kind of injection derived from Chinese traditional herb, had strongly inhibitory effects on the expression of TACE mRNA and secretion of sTNFα stimulated by LPS. The above results suggested that the TACE indeed involved in delivering and processing of pro-TNFα during the period of LPS stimulation and the study about the regulator/inhibitors of TACE gene expression would be very important to develop new types of therapy agents against toxic and side effects of sTNFα during the peroid of infection/inflammation to human body.

Keywords

TNFα / TNFα converting enzyme / lipopolysaccharides / anti-sense oligodeoxyribonucleotide

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