Motti C, Nuzzo M, Meola A, Galfré G, Felici F, Cortese R, Nicosia A, Monaci P
Istituto di Ricerche di Biologia Molecolare P. Angeletti, Pomezia, Roma, Italy.
Gene. 1994 Sep 2;146(2):191-8. doi: 10.1016/0378-1119(94)90292-5.
We used two mouse monoclonal antibodies (mAb) specific for the human hepatitis B virus surface antigen (HBsAg) to screen a random peptide library of 15 amino-acid residues displayed as a fusion to protein III of filamentous phage M13. By a combination of affinity selection, immuno-screening and ELISA techniques, we selected peptides that are recognized by the anti-HBsAg mAb and show aa similarity with the natural antigen. The selected phage-displayed epitopes (phagotopes) behave as antigenic mimics of HBsAg. One phagotope is specifically recognized by human sera from HBsAg-immunized individuals, pointing to the possible use of phagotopes as markers to detect the presence of specific Ab in the serum. The same phagotope also elicits Ab directed against HBsAg in mice, indicating that mAb-selected phagotopes can also be immunogenic mimics of the natural antigen. These findings demonstrate that it is possible to identify disease-specific epitopes that can be used as diagnostic reagents and as leads for the development of acellular vaccines.
我们使用两种针对人乙肝病毒表面抗原（HBsAg）的小鼠单克隆抗体（mAb），筛选一个由15个氨基酸残基组成的随机肽库，这些肽以与丝状噬菌体M13的蛋白III融合的形式展示。通过亲和选择、免疫筛选和酶联免疫吸附测定（ELISA）技术相结合的方法，我们筛选出了能被抗HBsAg mAb识别且与天然抗原具有氨基酸相似性的肽段。所筛选出的噬菌体展示表位（噬菌体位）表现为HBsAg的抗原模拟物。其中一个噬菌体位能被来自接种过HBsAg的个体的人血清特异性识别，这表明噬菌体位有可能用作检测血清中特异性抗体存在的标志物。同一个噬菌体位在小鼠中也能引发针对HBsAg的抗体，这表明经mAb筛选出的噬菌体位也可以是天然抗原的免疫原性模拟物。这些发现表明，识别疾病特异性表位并将其用作诊断试剂以及开发无细胞疫苗的先导物是有可能的。
