合成三肽囊素阳性噬菌体模拟七肽的免疫活性初步研究

The immune activity of synthetic heptapeptide derived from positive phage mimic of bursin

为探讨三肽囊素(Bursin)模拟七肽的免疫活性及其与Brusin的相关性,本研究根据Bursin阳性噬菌体展示七肽库中筛选得到的氨基酸序列(MTTNLQQ)人工合成该七肽。以ELISA和竞争ELISA检验合成七肽与Bursin在体外的免疫学反应的相关性;比较不同剂量的合成七肽(设定Bursin作为对照)对鸡新城疫病毒(NDV)弱毒疫苗(La Sota株)在鸡体诱导的特异性免疫应答的影响。结果显示合成七肽与抗Bursin单克隆抗体(2F9-4/HU2)能够特异性结合并且该结合作用可被Bursin阻断;动物试验的结果表明,低剂量(0.09mg)的合成七肽对疫苗诱导的体液免疫应答的增强作用与Bursin相当,而且高剂量(0.3mg)的合成七肽对细胞免疫应答具有一定的增强作用。因此,认为七肽序列MTTNLQQ具有与Bursin类似的免疫活性。

To study the immune and biological activity of heptapeptide （MTTNLQQ） and identify whether it could substitute of bursin, the heptapeptide was synthesized and tested with ELISA and competitive ELISA, the result showed that the artifical synthetic heptapeptide was a specific peptide binding to anti-bursin monoclonal antibody （2F9-4/HU2）. The heptapeptide at different dose were injected to chickens to test the effect of immune enhancement, the result showed that the heptapeptide at low dose （0.09 mg） was similar to bursin which enhanced the effect of vaccine immune in vivo experiment. Furthermore, heptapeptide at high dose （0.3 mg） was proved to enhance effectly on cellular immunity. In conclusion, the sequence of MTTNLQQ could be a mimetic peptide of bursin.