从噬菌体表面展示肽库中筛选葡萄球菌B型肠毒素抑制剂

Screening of Staphylococcal Enterotoxin B Inhibitor from Phage Peptide Libraries

通过生物淘选,从噬菌体表面展示12肽肽库中筛选能与葡萄球菌B型肠毒素(staphylococcalenterotoxinB ,SEB)结合且能抑制其肠毒活性的特异性短肽.采用Phage ELISA和MTT鉴定所得目的肽的亲和性;根据优势噬菌体阳性克隆序列合成相应多肽.利用竞争ELISA研究合成肽与SEB单克隆抗体竞争结合SEB的情况;通过动物实验考察其抑制SEB的超抗原特性和肠毒活性情况.筛选所得短肽在一定浓度范围内可以抑制SEB对鼠脾淋巴细胞的激活;合成肽与SEB质量比为16 0∶1时,合成肽可较好地抑制SEB对乳猫的肠毒活性,并对SEB引起的小鼠致死具有明显保护作用.结果表明,初步得到了能与SEB特异结合并能抑制SEB超抗原特性和肠毒活性的短肽,为进一步研制SEB高效抑制剂奠定了基础.

The specific peptides which can bind with staphylococcal enterotoxin B (SEB) and inhibit SEB′s enterotoxin activity were obtained by biopanning from 12-mer polypeptide libraries. The affinity activity of peptide was evaluated by employing the Phage-ELISA,MTT assay. The competition ELISA was used to appraise synthetic peptide activity of competion with anti-SEB monoclonal antibody(McAb). The animal experiments were used to evaluate the screened peptides which could suppress the SEB toxivity and enterotoxin. The results proved that the 12-mer peptide could suppress the proliferation of spleen lymphocytes in mice. At the ratio 160∶1 (synthetic 12-mer peptide∶SEB), the peptide could protect little cats from attack of enterotoxin.And the group of mice with the peptide survive better than control group. The resuts could provide a basis for developing inhibitors of SEB.