ABSTRACT
Objective To investigate the lipoteichoic acid(LTA) induced apoptosis and the expression of inflammatory cytokines in human alveolar macrophage (AM) and the anti-apoptotic and anti-inflamatory effect of moxifloxacin (MXF).Methods Obtained human AM from bronchoalveolar lavage and used MTT assay to observe the effects of LTA and MXF on cell activity,optical microscope to investigate the change of the cell morphology,flow cytometry to assess cell apoptosis,RT-PCR to detect the mRNA levels of TLR2,IL-1 β,IL-8 and TNF-α,ELISA for the production of IL-8 to exam RT-PCR.Results LTA showed cytotoxicity on AM in a dose-dependent manner ( P＜0.05 ) ; MXF inhibited the effect of LTA without cytotoxicicy ( P＜0.05 ).LTA promoted apoptosis ( P＜0.05 ) and the mRNA expressions of TRL2,IL-1 β,IL-8 and TNF-α significantly in AM (P＜0.05),the peaks and peak time ofthe above factors were (3.56±0.03) at 12 h,(46.63±7.06) at 6 h,(28.07±1.24) at 12 h and (2.34 ±0.50) at 3 h respectively and increased the release of IL-8 protein level at 24 h (P＜0.05).MXF inhibited the cell apoptosis and the above mRNA expression at 12h ( P＜0.05 ),and inhibited the IL-8 protein level at 24 h( P＜0.05 ).Conclusion LTA showed cytotoxicity on AM,induced AM apoptosis and increased the expression of TLR2,IL-I β,IL-8 and TNF-α of AM ; MXF could protect AM through inhibiting of the above effects and may play a key role beside bactericidal effect in gram-positive bacteria pneumonia.