FILAMENTOUS FUSION PHAGE

丝状融合噬菌体展示克隆的 DNA插入传染性病毒颗粒的表面。噬菌体 携带特定外源决定簇的人可以被亲和纯化 有了抗体，就可以很容易地纯化像 在原始混合物中每1亿人中有1人。将制定方法 用于构建包含1亿个元素的融合噬菌体“库” 不同的外源DNA插入，这样就可以充分发挥 技术可以被利用。表位文库的概念 举例说明了融合噬菌体可能被用于的用途。这个 在这个文库中插入的外来DNA可能是合成的DNA 随机序列。数十亿个短氨基酸序列将是 在一个1亿克隆库中被代表；它很可能， 因此，它将包含简短的决定因素(“表位”)。 可被任何抗蛋白质抗体识别。这一想法将得到检验 用针对肌红蛋白的抗体，一种小的蛋白质 他们的抗原性结构已被深入研究 合成肽。结果应该会产生大量新的 关于抗蛋白质抗体的特异性的信息-- 涉及免疫系统如何免疫的根本问题的信息 系统设法特别识别一个看似无限的 不同蛋白质抗原的曲目。他们还应该 指出表位在未来应用的可行性 图书馆。一种可能性是它可以被用来确定 由一种有趣的抗体识别的表位--比如说， 对某些疾病具有保护性免疫力。此信息 然后可以用来设计合成疫苗或免疫原 能够在其他人身上引发类似的抗体--所有 而不必克隆和分析编码天然 抗原。

Filamentous fusion phage display the amino acids coded by a cloned DNA insertion the surface of an infectious virus particle. Phage bearing a particular foreign determinant can be affinity-purified with antibody, making it easy to purify clones that are as rare as 1 in 100 million in the original mixture. Methods will be devised for constructing fusion-phage "libraries" containing 100 million different foreign DNa inserts, so that the full potential of the technology can be exploited. The concept of an epitope library exemplifies the uses to which fusion phage might be put. The foreign DNA inserts in this library would be synthetic DNa with random sequence. Billions of short amino acid sequences would be represented in a 100-million-clone library; it is likely, therefore, that it will contain short determinants ("epitopes") recognized by any anti-protein antibody. This idea will be tested with antibodies directed against myohemerythrin, a small protein whose antigenic structure has been intensively studied with synthetic peptides. The results should yield a wealth of new information about the specificity of anti-protein antibodies-- information that touches on the fundamental issue of how the immune system manages to specifically recognize a seemingly unlimited repertoire of different protein antigens. They should also indicate the feasibility of future applications of the epitope library. One possibility is that it could be used to determine the epitope recognized by an interesting antibody--one, say, that confers protective immunity to some disease. This information could then be used to design a synthetic vaccine or immunogen capable of eliciting similar antibodies in other individuals--all without having to clone and analyze the gene encoding the natural antigen.