Lipid-associated membrane proteins of Mycoplasma genitalium activate NF-κB via Toll-like receptors 2

Abstract

Objective To investigate whether nuclear transcription factor κB(NF-κB) through Toll-like receptors 2(TLR2) was activated by lipid-associated membrane proteins(LAMPs) of Mycoplasma genitalium.Methods LAMPs were extractded and THP-1 cells were stimulated.The activation of NF-κBp65 was detected by ELISA and the expression of TLR2 mRNA was detected by RT-PCR.Effects of TLR2 neutralizing antibody on LAMPs induced the activation of NF-κBp65 was analyzed by ELISA.After LAMPs stimulated 293T cells with the co-transfection pFLAG-TLR2,pNF-κB-luc,pRL-TK,the activity of NF-κB firefly luciferase and pRL-TK Renilla luciferase were detected by the dual-luciferase reporter gene,to analyzed the role of TLR2-mediated NF-κB activation by LAMPs in 293T cells.Results The activation of NF-κBp65 was mediated in LAMPs induced THP-1 cells and was significantly increased by LAMPs in a dose dependent manner.when LAMPs was 4.0 μg/ml,the activation of NF-κBp65 was the highest level.TLR2 mRNA expression was up-regulated by LAMPs in THP-1 cells.TLR2 neutralizing antibody could inhibit the activation of NF-κB by 60% in LAMPs stimulated THP-1.NF-κB fluorescence was significantly increased by co-transfection pFLAG-TLR2 in a dose-dependent manner. ConclusionMycoplasma genitalium-derived lipid-associated membrane proteins activate NF-κB via TLR2 and the activation of TLR2-mediated play an important role in pathogenic process of LAMPs. Key words: Mycoplasma genitalium; Lipid-associated membrane proteins; Toll-like receptors 2; Nuclear transcription factor κB