Human-rat chimeric anti-occludin monoclonal antibodies inhibit hepatitis C virus infection
Human-rat chimeric anti-occludin monoclonal antibodies inhibit hepatitis C virus infection
复制标题
人鼠嵌合抗occludin单克隆抗体抑制丙型肝炎病毒感染
DOI：
10.1016/j.bbrc.2019.05.019
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发表时间：
2019
影响因子：
3.1
通讯作者：
Fukasawa Masayoshi
中科院分区：
文献类型：
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作者：
Shimizu Yoshimi;Yoneda Kohei;Shirasago Yoshitaka;Suzuki Takeru;Tada Minoru;Ishii-Watabe Akiko;Sugiyama Kazuo;Suzuki Tetsuro;Wakita Takaji;Yagi Kiyohito;Kondoh Masuo;Fukasawa Masayoshi
封闭蛋白（OCLN）是一种完整的跨膜蛋白，是丙型肝炎病毒（HCV）感染所必需的宿主进入因子，是一种有希望的HCV治疗靶向分子。我们先前制备的大鼠抗OCLN单克隆抗体（mAbs）在体外和体内均能有效预防HCV感染。在本研究中，我们尝试使用基因工程来改善细胞外环结构域识别抗OCLN mAb（即克隆1-3和37-5）的可药用性。为了避免抗体依赖性细胞毒性诱导的不良反应并增强抗体稳定性，我们通过将每个大鼠抗OCLN mAb的轻链和重链可变区移植到人IgG 4 m的可变区中，开发了人-大鼠嵌合免疫球蛋白G4 S228 P突变体（IgG 4 m）形式的克隆1-3和37 -5（分别命名为Xi 1-3和Xi 37-5）。构建的Xi 1-3和Xi 37-5嵌合体表现出与每个亲本大鼠抗OCLN mAb相似的亲和力和特异性水平，并且Fcγ受体Ⅲa不被抗原结合的嵌合mAb激活，如预期的那样。两种嵌合单抗均能抑制不同基因型HCV的体外感染。这些结果表明，IgG 4 m形式的人-大鼠嵌合抗OCLN mAb可能是具有泛基因型抗HCV活性的宿主靶向抗病毒药物的潜在候选分子。
Occludin (OCLN), an integral tetra-spanning plasma membrane protein, is a host entry factor essential for hepatitis C virus (HCV) infection, making it a promising host-targeting molecule for HCV therapeutic intervention. We previously generated rat anti-OCLN monoclonal antibodies (mAbs) that strongly prevented HCV infectionin vitroandin vivo. In the present study, we attempted to improve the druggability of the extracellular loop domain-recognizing anti-OCLN mAbs, namely clones 1–3 and 37-5, using genetic engineering. To avoid adverse reactions induced by antibody-dependent cellular cytotoxicity and enhance the antibody stability, we developed human-rat chimeric immunoglobulin G4 S228P mutant (IgG4m) forms of clones 1–3 and 37-5 (named Xi 1–3 and Xi 37-5, respectively) by grafting the variable regions of the light and heavy chains of each rat anti-OCLN mAb into those of human IgG4m. The constructed Xi 1–3 and Xi 37-5 chimeras demonstrated levels of affinity and specificity similar to each parental rat anti-OCLN mAb, and the Fcγ receptor Ⅲa was not activated by the antigen-bound chimeric mAbs, as expected. Both chimeric mAbs inhibitedin vitroinfection with various HCV genotypes. These results indicate that the IgG4m forms of human-rat chimeric anti-OCLN mAbs may be potential candidate molecules of host-targeting antivirals with pan-genotypic anti-HCV activity.