A member of a specific binding pair (sbp) is identified by expressing DNA encoding a genetically diverse population of such sbp members in recombinant host cells in which the sbp members are displayed in functional form at the surface of a secreted recombinant genetic display package (rgdp) containing DNA encoding the sbp member or a polypeptide component thereof, by virtue of the sbp member or a polypeptide component thereof being expressed as a fusion with a capsid component of the rgdp. The displayed sbps may be selected by affinity with a complementary sbp member, and the DNA recovered from selected rgdps for expression of the selected sbp members. Antibody sbp members may be thus obtained, with the different chains thereof expressed, one fused to the capsid component and the other in free form for association with the fusion partner polypeptide. A phagemid may be used as an expression vector, with said capsid fusion helping to package the phagemid DNA. Using this method libraries of DNA encoding respective chains of such multimeric sbp members may be combined, thereby obtaining a much greater genetic diversity in the sbp members than could easily be obtained by conventional methods.
特异性结合对(sbp)的一个成员是通过在
重组宿主细胞中表达编码这种 sbp 成员的遗传多样性群体的 DNA 来鉴定的,在
重组宿主细胞中,sbp 成员以功能形式显示在分泌型
重组基因显示包(rgdp)的表面,该包中含有编码 sbp 成员或其
多肽组分的 DNA,这是因为 sbp 成员或其
多肽组分是作为与 rgdp 的帽状组分融合的形式表达的。可通过与互补 sbp 成员的亲和力选择显示的 sbps,并从选定的 rgdps 中回收 DNA 以表达选定的 sbp 成员。这样就可以获得
抗体 sbp 成员,并表达其不同的链,其中一条与囊膜成分融合,另一条以自由形式与融合伙伴
多肽结合。噬菌体可用作表达载体,所述的噬菌体融合有助于包装噬菌体 DNA。使用这种方法可以组合编码这种多聚 sbp 成员各自链的 DNA 文库,从而获得比传统方法更容易获得的 sbp 成员遗传多样性。