大肠杆菌脂多糖2630模拟位的研究  

Study on mimotopes of E.coli lipopoly-saccharide 2630

作　　者：罗海波[1] 郑山根[1] 朱平[1] 富宁[1] 

机构地区：[1]第一军医大学免疫学教研室,广东广州510515

出　　处：《细胞与分子免疫学杂志》2004年第6期682-685,共4页Chinese Journal of Cellular and Molecular Immunology

基　　金：国家自然科学基金资助项目 (No .30 0 70 769)

摘　　要：目的 :利用纯化的抗大肠杆菌L2 6 30多抗筛选噬菌体环七肽库 ,以获得可模拟脂多糖 (LPS)表位的短肽克隆。方法 :以亲和层析纯化的抗大肠杆菌L2 6 30多克隆抗体为靶分子 ,筛选噬菌体随机环七肽库 ,用双夹心ELISA和竞争抑制ELISA鉴定阳性噬菌体克隆的抗原性。结果 :对噬菌体环肽库进行 3轮筛选后 ,随机挑选 2 0个克隆 ,经鉴定其中 12个可与抗L2 6 30抗体结合 ,即为阳性克隆 ;其中有 5个阳性噬菌体克隆表现出与抗鼠伤寒沙门氏菌LPS多抗结合的活性 ,提示这 5个噬菌体展示的短肽具有模拟大肠杆菌LPS及鼠伤寒沙门氏菌LPS共同表位的性质。经DNA序列分析显示 ,其中 8个克隆的氨基酸序列具有X DGLL XX或X EDGLL X保守序列 ,其余 4个克隆的序列均不相同。结论 :筛选获得的噬菌体环七肽克隆具有模拟大肠杆菌LPS表位的活性 ,为大肠杆菌L2 6 30多表位模拟短肽。其中AIM: To screen mimotopes of E.coli lipopolysaccharide(LPS) 2630 from c7c phage display peptide library. METHODS: The LPS mimotopes were screened from c7c phage display peptide library by using affinity chromatograph-purified polyclonal antibody against E.coli LPS 2630(L2630), and the antigenicity of selected clones was identified by ELISA. (RESULTS:) After 3 rounds of biopanning, 12 out of 20 phage clones were identified as positive clones which could bind to polyclonal anti-L2630 antibody, and 5 of these 12 clones could bind to polyclonal anti-S.typhi LPS 7261(L7261) antibody. The deduced amino acid sequence analysis showed that 8 of 12 clones had the conservative sequence: X-DGLL-XX or X-EDGLL-X. CONCLUSION: The peptides displayed on these phage clones can mimic the epitopes of L2630, and 5 of these phage clones mimic the common epitopes of L2630 and L7261.

关 键 词：脂多糖 模拟肽 噬菌体肽库 

分 类 号：R392.33[医药卫生—免疫学]