多粘菌素B及其模拟肽体外抗内毒素的实验研究  

Experimental studies of polymyxin B and its mimic peptide anti-LPS in vitro

作　　者：万志红[1] 王宇明[1] 刘国栋[1] 

机构地区：[1]中国人民解放军第三军医大学附属西南医院全军感染病研究所,重庆市400038

出　　处：《世界华人消化杂志》2003年第8期1200-1202,共3页World Chinese Journal of Digestology

摘　　要：方法:LPS(或FITC-LPS)100μg/L分别与PMB 100mg/L、peptide 0 100mg/L、peptide1 100mg/L、PBS,37℃孵育30min后(分别加入50mL/L NHS)刺激PBMC,用流式细胞仪检测FITC-LPS与PBMC的结合能力及CD14表达;ELISA法检测培养上清中细胞因子TNFα、IL-6含量。结果:FITC-LPS分别与PMB、peptidel孵育后,细胞膜平均通道荧光显著减少,LPS与PBMC的结合能力显著降低(分别为8.1±1.8 vs 15.8±4.5 P<0.01;8.5±2.0 vs15.8±4.5 P<0.01)。100μg/L LPS刺激PBMC3h后CD14阳性率明显增加;LPS分别与PMB和peptidel预孵育后可显著降低LPS刺激PBMC细胞膜CD14表达(分别为45.5±6.2％vs 68±5.5％ P<0.01;43.2±4.1％ vs 68±5.5％ P<0.01),LPS刺激PBMC分泌TNF-α和IL-6显著增加,LPS分别与PMB和peptidel预孵育后能显著减少细胞因子TNF-α(分别为15.30±1.0 vs 45.9±5.7 P<0.01;18.2土0.9 vs45.9±5.7 P<0.01)和IL-6分泌(分别为50.5±4.2 vs 176.4±12.1 P<0.01;58.1± 4.1 vs 176.4±12.1 P<0.01)。结论:多粘菌素B及其模拟肽(Peptidel)可能通过下调PBMC CD14表达,降低细胞因子水平来减少LPS诱导的炎症反应。AIM: To observe the binding ability of FITC-LPS and PMBC, changes of IL-6,TNF α before and after polymyxin B (PMB) or its mimic peptide treatment. METHODS: LPS (or FITC-LPS) 100 μg/L was incubated with PMB 100 mg/L, peptide 0: 100 mg/L, peptide 1: 100 mg/L or PBS at 37℃ and 5 mL/L normal human serum respectively for 30 min to stimulate PBMC. Binding ability of FITC-LPS and CD14 expression of PBMC were assayed by flow cytometer; IL-6 and TNF α level in culture supernatant were assayed by ELISA. RESULTS: After incubation with PMB or peptide 1, mean fluorescence intensity of FITC-LPS binding to cell mem- brane decreased (8.1±1.8 vs 15.8±4.5 P<0.01; 8.5±2.0 vs 15.8±4.5 P<0.01, respectively). Positive rate of CD14 increased in 3 h after LPS stimulation, Incubation with PMB or peptide 1 could reduce CD14 expression of PBMC stimulated by LPS (45.5±6.2 % vs 68±5.5 % P<0.01; 43.2±4.1 % vs 68±5.5 % P<0.01, respectively). Pretreatment with PMB or peptide 1 could decrease TNF-α(15.30±1.0 vs 45.9±5.7 P<0.01; 18.2±0.9 vs 45.9±5.7 P<0. 01, respectively) and IL-6 level (50.5±4.2 vs 176.4±12.1 P<0.01; 58.1±4.1 vs 176.4±12.1 P<0.01, respectively) stimulated by LPS gignificantly. CONCLUSION: PMB and its minic peptide (peptide 1) might suppress inflammation stimulated by LPS via down-regulating CD14 expression, and decrease cytokines level.

关 键 词：多粘菌素B 模拟肽 内毒素 实验 细胞因子 TNFΑ IL-6 肠源性内毒素血症 肝炎 

分 类 号：R575[医药卫生—消化系统]