用噬菌体多肽库筛选日本血吸虫表膜抗原的模拟表位

为探索可用于诊断的模拟表膜抗原。采用纯化的兔抗表膜抗原IgG作探针 ,免疫筛选噬菌体随机十二肽库 ,经 3轮生物淘洗后 ,随机挑选 30个噬菌体克隆 ,用ELISA检测其与筛选抗体的特异性结合 ,选择两个阳性克隆进行DNA序列测定 ,并用斑点ELISA比较检测正常人和日本血吸虫病患者血清各 10份。结果显示 ,随机挑选的 30个克隆中有 9个噬菌体克隆与筛选的抗体有特异性的结合反应。DNA测序结果显示 ,两个阳性噬菌体克隆 (携带的抗原表位 )所演绎的氨基酸序列与GenBank已知的氨基酸序列无同源性。斑点ELISA结果显示两个抗原表位可被血吸虫病患者血清呈特异性识别

Immunoscreening Mimic Epitope of Schistosoma Japonicum Membrane Antigen by Phage Display Peptide

In order to explore an membrane mimotope in the diagnostic antigens of Schistosoma Japonicum specific IgG was purified from polyclonal antibodies (polyAb) which was against membrane of Schistosoma japonicum (SjMAg),and polyAb were used as probe to immunoscreen phage display random 12 peptides library Thirty clones were randomly selected and examined by ELISA with SjMAg immune serum The positive clones were sequenced and were used in the dot ELISA with 10 sera of schistosomiasis patients and normal human,respectively The results showed that nine phage clones displayed high affinity and specificity to anti membrane antibodies of Schistosoma japonicum .The sequence of two peptides (Q2 and Q6) showed no homology with other sequence in the GenBank In dot ELISA with Q2 and Q6,8 and 7 of 10 sera samples from schistosomiasis patients showed positive reaction,respectively,and sera from 10 normal persons all showed negative reaction with these two short peptides