Abstract: Toll-like receptors(TLRs)are important pattern recognition receptors in innate immunity.They play an important role in innate and acquired immune responses.The objective of this study was to assess the effect of TLR2-and TLR4-BB peptides(BBPs)on LPS-stimulated TNF-αmRNA expression in peritoneal macrophages of mouse and to unravel its underling mechanism.The mouse peritoneal macrophages were isolated and subsequently cultured in vitro,and the mRNA expression of TNF-αwas examined quantitatively by real-time fluorescent quantitative RT-PCR.Compared with the LPS-stimulated group,there was no significant difference in the mRNA expression of TNF-αin the CP control group(P>0.05);TLR2-and TLR4-BBPs decreased extremely significantly the mRNA and protein expression of TNF-αin peritoneal macrophages of mouse(P<0.01).These results demonstrate that TLR2-and TLR4-BBPs has inhibitory effect on mRNA expression of pro-inflammatory cytokine TNF-α.