Humoral response to oligomeric human immunodeficiency virus type 1 envelope protein.
Humoral response to oligomeric human immunodeficiency virus type 1 envelope protein.
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对寡聚人类免疫缺陷病毒 1 型包膜蛋白的体液反应。
DOI：
10.1128/jvi.70.2.753-762.1996
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发表时间：
1996
期刊：
影响因子：
--
通讯作者：
Doms,RW
中科院分区：
文献类型：
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作者：
RichardsonJr,TM;Stryjewski,BL;Broder,CC;Hoxie,JA;Mascola,JR;Earl,PL;Doms,RW
对人类免疫缺陷病毒1型（HIV-1）的体液免疫应答通常通过使用单体或变性包膜蛋白（Env）来研究。然而，保持四级结构的天然HIV-1 Env复合物引发的免疫应答与单体或变性Env所见的免疫应答在性质上不同。为了更准确地评估HIV-1感染引起的抗体的水平和类型，我们开发了一种抗原捕获酶联免疫吸附试验，该试验使用含有gp 120和gp 41胞外域的可溶性寡聚体形式的HIV-1 IIIB Env（gp 140）。gp 140被各种单克隆抗体（MAb）捕获，保留了其天然的寡聚体结构：它结合CD 4，并被MAb识别为gp 120和gp 41中的构象表位，包括gp 41中的寡聚体特异性表位。我们比较了进化枝B和进化枝E血清样品与捕获的Env制剂的反应性，发现虽然两者与寡聚gp 140反应同样好，但进化枝B血清与单体gp 120的反应比进化枝E样品更强烈。然而，当gp 120被V3环单克隆抗体捕获时，这些差异被最小化，这可能导致CD 4结合位点的暴露增加。我们还测量了血清样品阻断MAb与gp 120和gp 41中表位结合的能力。进化枝B血清样品一致地阻断寡聚体依赖性MAb与gp 41的结合，并且在稍低的程度上阻断MAb与gp 120中的CD 4结合位点的结合。分化体E血清样品显示出对寡聚体依赖性gp 41抗体的相等或更大的阻断，以及对CD 4结合位点MAb的相当少的阻断。最后，我们发现进化枝B血清中< 5%的抗体结合仅存在于单体gp 120中的表位，30%结合存在于单体gp 120和寡聚体gp 140中的表位，70%结合存在于寡聚体gp 140（包括gp 41）中的表位。因此，捕获的寡聚Env紧密地反映了病毒体和感染细胞表面上Env蛋白的抗原特征，保留了被针对不同进化枝产生的抗体识别的高度保守的表位，并且使得有可能检测到比天然单体gp 120大得多的血清中总抗HIV-1 Env活性的分数。
The humoral immune response to human immunodeficiency virus type 1 (HIV-1) is often studied by using monomeric or denatured envelope proteins (Env). However, native HIV-1 Env complexes that maintain quaternary structure elicit immune responses that are qualitatively distinct from those seen with monomeric or denatured Env. To more accurately assess the levels and types of antibodies elicited by HIV-1 infection, we developed an antigen capture enzyme-linked immunosorbent assay using a soluble, oligomeric form of HIV-1IIIB Env (gp140) that contains gp120 and the gp41 ectodomain. The gp140, captured by various monoclonal antibodies (MAbs), retained its native oligomeric structure: it bound CD4 and was recognized by MAbs to conformational epitopes in gp120 and gp41, including oligomer-specific epitopes in gp41. We compared the reactivities of clade B and clade E serum samples to captured Env preparations and found that while both reacted equally well with oligomeric gp140, clade B seras reacted more strongly with monomeric gp120 than did clade E samples. However, these differences were minimized when gp120 was captured by a V3 loop MAb, which may lead to increased exposure of the CD4 binding site. We also measured the ability of serum samples to block binding of MAbs to epitopes in gp120 and gp41. Clade B serum samples consistently blocked binding of oligomer-dependent MAbs to gp41 and, to a slightly lesser extent, MAbs to the CD4 binding site in gp120. Clade E serum samples showed equivalent or greater blocking of oligomer-dependent gp41 antibodies and considerably less blocking of CD4-binding-site MAbs. Finally, we found that < 5% of the antibodies in clade B sera bound to epitopes present only in monomeric gp120, 30% bound to epitopes present in both monomeric gp120 and oligomeric gp140, and 70% bound to epitopes present in oligomeric gp140, which includes gp41. Thus, captured oligomeric Env closely reflects the antigenic characteristics of Env protein on the surface of virions and infected cells, retains highly conserved epitopes that are recognized by antibodies raised against different clades, and makes it possible to detect a much greater fraction of total anti-HIV-1 Env activity in sera than does native monomeric gp120.