噬菌体7肽文库筛查类风湿关节炎相关抗体及分析

目的筛选和鉴定与类风湿关节炎(rheumatoid arthritis,RA)患者血清特异性结合的噬菌体7肽,并分析其实际意义。方法采用30例正常人混合血清和30例RA患者混合血清作为筛选配基对噬菌体随机7肽库进行亲和筛选、扩增,获得RA血清特异性结合的噬菌体克隆。用患者混合血清进行Dot-ELISA实验鉴定获得的噬菌体克隆,进一步用RA患者及正常人血清各12例筛选阳性噬菌体的混合克隆。对鉴定的噬菌体克隆进行测序,并分析其同源性。结果获得17个与RA患者混合血清特异性结合的阳性克隆。阳性噬菌体混合克隆与RA患者个体血清反应阳性率明显高于其与正常人血清的反应率。序列分析显示阳性噬菌体克隆的抗原表位之间无共有序列,但与杆菌、球菌等有一定的同源性。结论 RA患者血清中存在与病原体抗原表位结合的抗体成分,提示RA的发病可能与病原体感染有关。

Screening and analyzing of the phage-display random 7 amino acid peptides-specific antibodies in rheumatoid arthritis sera

Objective To screen and identify the phage-display random 7 amino acid peptides specific to the antibodies in rheumatoid arthritis(RA) sera and to analyze practical significance of the peptides.Methods The RA specific phage clones were obtained after binding with the mixture of sera from RA patients and normal controls(n=30 per group) as ligand by screening in the phage random 7 peptide library.Then Dot-ELISA was performed to identify the RA specific phage clones reactive to sera of RA patients and normal controls individually;and identified positive phage clones were further screened out by using sera from RA and normal controls(n=12 per group).Finally the identified positive phage clones were sequenced and the homology was also analyzed.Results A total of 17 positive phage clones specific to RA sera were obtained.The reactivity of the mixture of positive phage clones combined with RA sera was significantly higher than that with the normal controls.Sequence analysis showed that there was no consensus sequence between the antigenic epitopes in the identified phage clones.However,the identified phage clones had homology with Bacillus,coccus.Conclusion The antibody content combined with the pathogen epitope exists in the RA sera,indicating that the pathogenesis of RA might be related with the pathogen infection.