Pedreño-Lopez Nuria, Dang Christine M, Rosen Brandon C, Ricciardi Michael J, Bailey Varian K, Gutman Martin J, Gonzalez-Nieto Lucas, Pauthner Matthias G, Le Khoa, Song Ge, Andrabi Raiees, Weisgrau Kim L, Pomplun Nicholas, Martinez-Navio José M, Fuchs Sebastian P, Wrammert Jens, Rakasz Eva G, Lifson Jeffrey D, Martins Mauricio A, Burton Dennis R, Watkins David I, Magnani Diogo M
Department of Pathology, University of Miami Leonard M. Miller School of Medicine, Miami, FL 33136, USA.
Medical Scientist Training Program, University of Miami Leonard M. Miller School of Medicine, Miami, FL 33136, USA.
Mol Ther Methods Clin Dev. 2020 Feb 13;16:225-237. doi: 10.1016/j.omtm.2020.01.010. eCollection 2020 Mar 13.
Structural characterization of the HIV-1 Envelope (Env) glycoprotein has facilitated the development of Env probes to isolate HIV-specific monoclonal antibodies (mAbs). However, preclinical studies have largely evaluated these virus-specific mAbs against chimeric viruses, which do not naturally infect non-human primates, in contrast to the unconstrained simian immunodeficiency virus (SIV)mac239 clone. Given the paucity of native-like reagents for the isolation of SIV-specific B cells, we examined a method to isolate SIVmac239-specific mAbs without using Env probes. We first activated virus-specific B cells by inducing viral replication after the infusion of a CD8β-depleting mAb or withdrawal of antiretroviral therapy in SIVmac239-infected rhesus macaques. Following the rise in viremia, we observed 2- to 4-fold increases in the number of SIVmac239 Env-reactive plasmablasts in circulation. We then sorted these activated B cells and obtained 206 paired Ab sequences. After expressing 122 mAbs, we identified 14 Env-specific mAbs. While these Env-specific mAbs bound to both the SIVmac239 SOSIP.664 trimer and to infected primary rhesus CD4 T cells, five also neutralized SIVmac316. Unfortunately, none of these mAbs neutralized SIVmac239. Our data show that this method can be used to isolate virus-specific mAbs without antigenic probes by inducing bursts of contemporary replicating viruses .
对HIV-1包膜（Env）糖蛋白的结构表征促进了Env探针的开发，以分离HIV特异性单克隆抗体（mAb）。然而，临床前研究主要评估了这些病毒特异性mAb对嵌合病毒的作用，与无限制的猿猴免疫缺陷病毒（SIV）mac239克隆不同，嵌合病毒不会自然感染非人灵长类动物。鉴于用于分离SIV特异性B细胞的天然样试剂匮乏，我们研究了一种不使用Env探针来分离SIVmac239特异性mAb的方法。我们首先通过在感染SIVmac239的恒河猴中注入CD8β耗竭性mAb或停止抗逆转录病毒治疗后诱导病毒复制，来激活病毒特异性B细胞。在病毒血症上升后，我们观察到循环中SIVmac239 Env反应性浆母细胞数量增加了2至4倍。然后我们对这些活化的B细胞进行分选，并获得了206对抗体序列。在表达了122种mAb后，我们鉴定出14种Env特异性mAb。虽然这些Env特异性mAb与SIVmac239 SOSIP.664三聚体以及感染的原代恒河猴CD4 T细胞都结合，但其中五种也中和了SIVmac316。不幸的是，这些mAb都没有中和SIVmac239。我们的数据表明，这种方法可以通过诱导当代复制病毒的爆发来分离不使用抗原探针的病毒特异性mAb。
