Antibody Screening System Using a Herpes Simplex Virus (HSV)-Based Probe To Identify a Novel Target for Receptor-Retargeted Oncolytic HSVs
Antibody Screening System Using a Herpes Simplex Virus (HSV)-Based Probe To Identify a Novel Target for Receptor-Retargeted Oncolytic HSVs
复制标题
使用基于单纯疱疹病毒（HSV）的探针的抗体筛选系统鉴定受体重靶向溶瘤HSV的新靶点
DOI：
10.1128/jvi.01766-20
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发表时间：
2021-05-01
影响因子：
5.4
通讯作者：
Tahara, Hideaki
中科院分区：
文献类型：
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作者：
Ikeda, Hitomi;Uchida, Hiroaki;Tahara, Hideaki
单纯疱疹病毒（HSV）是开发溶瘤病毒治疗的一个很有前途的工具。我们最近报道了一个受体重靶向溶瘤性单纯疱疹病毒的平台，该平台将单链抗体（scFvs）整合到包膜糖蛋白D （gD）中，介导病毒通过肿瘤相关抗原进入。因此，开发一种有效的系统来筛选可能介导HSV进入gD的抗体是有用的。我们通过基因融合一个gD突变体构建了一个基于单纯疱疹病毒的筛选探针，该突变体与单纯疱疹病毒的真实进入受体和链球菌蛋白g的抗体结合C结构域的结合能力被削弱。相反，当这种病毒与细胞膜上的抗原特异性抗体结合时，它特异性地进入表达同源抗原的细胞。该病毒被用作探针，以鉴定通过识别细胞膜上的某些分子而不是真正的受体介导病毒进入的抗体。使用这种方法，我们鉴定了一种针对表调节蛋白（EREG）的抗体，该抗体主要被研究为一种分泌生长因子，而不一定是其以跨膜形式表达的前体。我们用抗EREG抗体构建了一个scFv插入到重靶向HSV平台中，发现重组病毒通过细胞表达的EREG特异性进入细胞。这种新的抗体筛选系统可能有助于发现独特的和意想不到的分子，这些分子可能用于受体重靶向的溶瘤性单纯疱疹病毒的进入。重要性：HSV进入细胞的趋向性依赖于其包膜gD与其真实受体之一的结合。通过将scFvs插入gD并进行适当的修饰，可以将其完全重定向到其他受体上。理论上，在与工程化gD结合后，除真实受体外的受体应诱导gD发生构象变化，从而激活病毒进入所需的下游机制。然而，受体用作重靶向病毒靶标的先决因素仍然知之甚少，并且很难预测哪些分子可能适合我们的重靶向HSV结构。我们基于HSV的探针将允许无偏倚地筛选介导病毒进入的抗体-抗原对，这可能是一个有用的工具，可以为我们的构建确定合适的抗体-抗原对，并增强我们对HSV和其他病毒感染期间病毒-细胞相互作用的理解。
Herpes simplex virus (HSV) is a promising tool for developing oncolytic virotherapy. We recently reported a platform for receptor-retargeted oncolytic HSVs that incorporates single-chain antibodies (scFvs) into envelope glycoprotein D (gD) to mediate virus entry via tumor-associated antigens. Therefore, it would be useful to develop an efficient system that can screen antibodies that might mediate HSV entry when they are incorporated as scFvs into gD. We created an HSV-based screening probe by the genetic fusion of a gD mutant with ablated binding capability to the authentic HSV entry receptors and the antibody-binding C domain of streptococcal protein G. This engineered virus failed to enter cells through authentic receptors. In contrast, when this virus was conjugated with an antibody specific to an antigen on the cell membrane, it specifically entered cells expressing the cognate antigen. This virus was used as a probe to identify antibodies that mediate virus entry via recognition of certain molecules on the cell membrane other than authentic receptors. Using this method, we identified an antibody specific to epiregulin (EREG), which has been investigated mainly as a secreted growth factor and not necessarily for its precursor that is expressed in a transmembrane form. We constructed an scFv from the anti-EREG antibody for insertion into the retargeted HSV platform and found that the recombinant virus entered cells specifically through EREG expressed by the cells. This novel antibody-screening system may contribute to the discovery of unique and unexpected molecules that might be used for the entry of receptor-retargeted oncolytic HSVs.IMPORTANCE The tropism of the cellular entry of HSV is dependent on the binding of the envelope gD to one of its authentic receptors. This can be fully retargeted to other receptors by inserting scFvs into gD with appropriate modifications. In theory, upon binding to the engineered gD, receptors other than authentic receptors should induce a conformational change in the gD, which activates downstream mechanisms required for viral entry. However, prerequisite factors for receptors to be used as targets of a retargeted virus remain poorly understood, and it is difficult to predict which molecules might be suitable for our retargeted HSV construct. Our HSV-based probe will allow unbiased screening of antibody-antigen pairs that mediate virus entry and might be a useful tool to identify suitable pairs for our construct and to enhance our understanding of virus-cell interactions during infection by HSV and possibly other viruses.