A monoclonal fab derived from a human nonimmune phage library reveals a new epitope on gp41 and neutralizes diverse human immunodeficiency virus type 1 strains
A monoclonal fab derived from a human nonimmune phage library reveals a new epitope on gp41 and neutralizes diverse human immunodeficiency virus type 1 strains
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DOI：
10.1128/jvi.01260-07
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发表时间：
2007-12-01
影响因子：
5.4
通讯作者：
Clore, G. Marius
中科院分区：
文献类型：
--
作者：
Gustchina, Elena;Louis, John M.;Clore, G. Marius
本文描述了一个单克隆Fab (Fab 3674)，通过对嵌合构建物ngg -gp41（包括一个暴露的gp41 N螺旋三聚体，在螺旋相融合到gp41的最小热稳定性外域）进行筛选，从人类非免疫噬菌体文库中选择。在env伪病毒中和实验中，Fab 3674被证明可以中和多种实验室适应的人类免疫缺陷病毒1型（HIV-1） B株和A、B、C亚型的原代分离株，尽管与2F5和4E10相比效力降低（约25倍）。Alamine扫描诱变将一个新的表位映射到gp41的N螺旋上的一个浅槽上，该浅槽暴露在gp41的6螺旋束构象中的两个C螺旋之间。二价Fab 3674和C34肽（一种来自gp41 C螺旋的有效融合抑制剂）在融合反应的相似阶段表现出协同中和HIV-1的作用，这进一步证明Fab 3674的表位是新的，不同于C34的结合位点。
A monoclonal Fab (Fab 3674) selected from a human nonimmune phage library by panning against the chimeric construct NccG-gp41 (which comprises an exposed coiled-coil trimer of gp41 N helices fused in the helical phase onto the minimal thermostable ectodomain of gp41) is described. Fab 3674 is shown to neutralize diverse laboratory-adapted B strains of human immunodeficiency virus type 1 (HIV-1) and primary isolates of subtypes A, B, and C in an Env-pseudotyped-virus neutralization assay, albeit with reduced potency (approximately 25-fold) compared to that of 2F5 and 4E10. Alamine scanning mutagenesis maps a novel epitope to a shallow groove on the N helices of gp41 that is exposed between two C helices in the fusogenic six-helix bundle conformation of gp41. Bivalent Fab 3674 and the C34 peptide (a potent fusion inhibitor derived from the C helix of gp41) are shown to act at similar stages of the fusion reaction and to neutralize HIV-1 synergistically, providing additional evidence that the epitope of Fab 3674 is new and distinct from the binding site of C34.