MOLECULAR PROFILE OF AN ANTIBODY-RESPONSE TO HIV-1 AS PROBED BY COMBINATORIAL LIBRARIES
MOLECULAR PROFILE OF AN ANTIBODY-RESPONSE TO HIV-1 AS PROBED BY COMBINATORIAL LIBRARIES
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DOI：
10.1006/jmbi.1993.1203
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发表时间：
1993-04-05
影响因子：
5.6
通讯作者：
BURTON, DR
中科院分区：
文献类型：
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作者：
BARBAS, CF;COLLET, TA;BURTON, DR
通过从噬菌体表面展示的组合IgG1κ文库中进行选择，已经产生了大量(33)与HIV-1表面糖蛋白gp120反应的人Fab片段。该文库是由长期无症状的艾滋病毒血清阳性供体制备的。对这些 Fab 序列的分析表明，重链可以分组，其中许多包含克隆内变体，几乎肯定对应于体内使用的链。可以通过链改组实验获得更多变体，其中给定的轻链与重链文库重组。重链混杂性，即重链与不同轻链配对并保留抗原结合的能力，取决于所考虑的特定重链，并且可能排除体内轻链配偶体的识别。这里检查的抗体主要针对 gp120 上的 CD4 结合位点，广泛反映供体的血清特征。这些抗体显示出广泛的体细胞修饰的证据，表明抗原驱动的反应。抗体的重链 CDR3 区显示出显着保守的延伸长度。一些数据还显示出 CDR3 中强烈的序列保守性，而 VH 基因的其余部分具有相当大的多样性，支持该区域在抗原识别中的核心作用。
A large number (33) of human Fab fragments reacting with HIV-1 surface glycoprotein gp120 have been generated by selection from a combinatorial IgGlκ library displayed on the surface of phage. The library was prepared from a long term asymptomatic HIV-seropositive donor. Analysis of the sequences from these Fabs shows the heavy chains can be placed in groups, many of which contain intraclonal variants, almost certainly corresponding to chains usedin vivo. Further variants can be accessedviachain shuffling experiments in which a given light chain is recombined with a library of heavy chains. Heavy chain promiscuity, i.e. the ability of heavy chains to pair with different light chains with retention of antigen binding, is dependent on the particular heavy chain considered and probably excludes the identification ofin vivolight chain partners. The antibodies examined here are primarily to the CD4 binding site on gp120 and broadly reflect the serum profile of the donor. The antibodies show evidence of extensive somatic modification indicative of an antigen-driven response. The heavy chain CDR3 regions of the antibodies show a remarkably conserved extended length. A number also show strong sequence conservation in CDR3 against a background of considerable diversity in the rest of the VH gene supporting a central role for this region in antigen recognition.