SLE患者血清中病原体相关噬菌体7肽的检测

Identification of systemic lupus erythematosus infection-associated epitope by random 7 peptide libraries displayed on phage

目的用噬菌体7肽库筛选系统性红斑狼疮（SLE）患者血清特异性抗体，测序分析其实际意义。方法先用30例正常人混合血清与噬菌体7肽库反应，未与正常人白清结合的7肽再与30例SLE患者混合血清结合，获得SLE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SLE患者及正常人血清各12例筛选阳性噬菌体的混合克隆，确定阳性噬菌体克隆与个体血清之间的结合情况，并对最终鉴定的噬菌体克隆进行测序与比对分析。结果混合的阳性噬菌体克隆与SLE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与杆菌、球菌、弧菌等微生物有同源性，与裂殖酵母属、链球菌属、立克次（氏）体属等有100％同源性，与人类抗原表位无关。结论SLE患者血清中存在与病原体抗原表位结合的抗体成分，提示SLE可能与病原体感染有关。

Objective To screen and identify the phage expressing random 7 amino acid peptide specific to the systemic lupus erythematosus （SLE） and analyze its practical significance. Methods Using the phage random 7 peptide library screening, the SLE specific phage clones were obtained by mixing with the sera from 30 SLE patients＂ and 30 normal controls respectively. Dot-ELISA was used to identify the SLE specific phage clones reacting to the sera of SLE patients and normal controls. Finally, the identified phages expressing random 7 amino acid peptides were sequenced and analyzed. Results Total 12 phages expressing random 7 amino acid peptides were obtained by phage peptide library screening and dot-ELISA identification. Sequence a- nalysis showed that the no homology was found between the sequences Of the deduced amino acid of the 7 antigen peptides and the sequence of human antigens. Peptides homology was found with coccus, coli, and vibrio. We found through further analysis that these sequences had high homology with the antigens of budding yeast, streptococcus, rickettisia. Conclusion There are antibodies in SLE patients against pathogen cpitopcs. The results imply that SLE may relate with infection.