Departamento de Bioquímica y Biología Molecular, Instituto Biofisika (CSIC, UPV/EHU), Universidad del País Vasco, Bilbao, Spain.
Department of Infectious Diseases, Virology, Universitätsklinikum Heidelberg, Heidelberg, Germany.
Front Immunol. 2018 Sep 4;9:1983. doi: 10.3389/fimmu.2018.01983. eCollection 2018.
The envelope of Human Immunodeficiency Virus type 1 (HIV-1) consists of a liquid-ordered membrane enriched in raft lipids and containing the viral glycoproteins. Previous studies demonstrated that changes in viral membrane lipid composition affecting membrane structure or curvature can impair infectivity. Here, we describe novel antiviral compounds that were identified by screening compound libraries based on raft lipid-like scaffolds. Three distinct molecular structures were chosen for mode-of-action studies, a sterol derivative (J391B), a sphingosine derivative (J582C) and a long aliphatic chain derivative (IBS70). All three target the viral membrane and inhibit virus infectivity at the stage of fusion without perturbing virus stability or affecting virion-associated envelope glycoproteins. Their effect did not depend on the expressed envelope glycoproteins or a specific entry route, being equally strong in HIV pseudotypes carrying VSV-G or MLV-Env glycoproteins. Labeling with laurdan, a reporter of membrane order, revealed different membrane structure alterations upon compound treatment of HIV-1, which correlated with loss of infectivity. J582C and IBS70 decreased membrane order in distinctive ways, whereas J391B increased membrane order. The compounds' effects on membrane order were reproduced in liposomes generated from extracted HIV lipids and thus independent both of virion proteins and of membrane leaflet asymmetry. Remarkably, increase of membrane order by J391B required phosphatidylserine, a lipid enriched in the HIV envelope. Counterintuitively, mixtures of two compounds with opposite effects on membrane order, J582C and J391B, did not neutralize each other but synergistically inhibited HIV infection. Thus, altering membrane order, which can occur by different mechanisms, constitutes a novel antiviral mode of action that may be of general relevance for enveloped viruses and difficult to overcome by resistance development.
人类免疫缺陷病毒 1 型（HIV-1）的包膜由富含筏状脂质的有序液体膜组成，其中包含病毒糖蛋白。先前的研究表明，改变影响膜结构或曲率的病毒膜脂质组成会损害感染性。在这里，我们描述了通过基于筏状脂质样支架的化合物库筛选而发现的新型抗病毒化合物。选择了三种不同的分子结构进行作用模式研究，一种固醇衍生物（J391B）、一种神经酰胺衍生物（J582C）和一种长脂肪链衍生物（IBS70）。这三种化合物都靶向病毒膜，并在融合阶段抑制病毒感染，而不会破坏病毒稳定性或影响病毒粒子相关的包膜糖蛋白。它们的作用不依赖于表达的包膜糖蛋白或特定的进入途径，在携带 VSV-G 或 MLV-Env 糖蛋白的 HIV 假型中同样有效。用膜有序性的报告子 laurdan 标记表明，化合物处理 HIV-1 后膜结构发生不同的改变，这与感染性丧失相关。J582C 和 IBS70 以不同的方式降低了膜有序性，而 J391B 增加了膜有序性。化合物对膜有序性的影响在从提取的 HIV 脂质生成的脂质体中得到重现，因此既独立于病毒粒子蛋白，也独立于膜双层的不对称性。值得注意的是，J391B 增加膜有序性需要富含 HIV 包膜的磷脂酰丝氨酸。出人意料的是，两种具有相反膜有序性效应的化合物（J582C 和 J391B）混合物并没有相互中和，而是协同抑制 HIV 感染。因此，改变膜有序性（可能通过不同的机制发生）构成了一种新的抗病毒作用模式，可能对包膜病毒具有普遍意义，并且难以通过耐药性发展来克服。
