Kaposi Sarcoma-Associated Herpesvirus Glycoprotein H Is Indispensable for Infection of Epithelial, Endothelial, and Fibroblast Cell Types
Kaposi Sarcoma-Associated Herpesvirus Glycoprotein H Is Indispensable for Infection of Epithelial, Endothelial, and Fibroblast Cell Types
复制标题
DOI：
10.1128/jvi.00630-19
复制
发表时间：
2019-08-01
影响因子：
5.4
通讯作者：
Ogembo, Javier Gordon
中科院分区：
文献类型：
--
作者：
Muniraju, Murali;Mutsvunguma, Lorraine Z.;Ogembo, Javier Gordon
卡波西肉瘤相关疱疹病毒（Kaposi sarcoma-associated herpesvirus，KSHV）是一种新发现的病原体，是引起卡波西肉瘤和两种B细胞来源的恶性肿瘤的病原体。迄今为止，还没有获得许可的KSHV疫苗。对KSHV如何在不同的人类细胞类型中启动体内急性原发性感染的理解不足，仍然限制了针对KSHV的有效疫苗的开发。糖蛋白H（gH）在疱疹病毒进入机制中的作用在很大程度上仍然没有得到解决。为了表征在病毒生命周期中对KSHV gH的需求和确定细胞嗜性，我们产生并表征了其中gH表达被废除的突变KSHV。利用含有完整重组KSHV基因组的细菌人工染色体和重组DNA技术，我们将终止密码子插入gH编码区。我们使用电子显微镜来揭示与野生型病毒相比，gH-无效突变体病毒正常地组装并从细胞中退出。使用纯化的病毒粒子，我们评估了gH-无效突变体在体外不同哺乳动物细胞类型中的感染性。与野生型病毒或含gH的回复突变体不同，gH无效突变体不能感染任何测试的上皮、内皮或成纤维细胞类型。然而，其感染B细胞的能力是不确定的，并且由于体外感染性通常较差，仍有待于在体内研究。总之，这些结果表明，GH是KSHV感染的高度允许的细胞类型，包括上皮，内皮细胞和成纤维细胞的关键。重要的疱疹病毒GH的所有同源物研究迄今已牵连在发挥重要作用，在病毒感染的不同的允许细胞类型。然而，gH在KSHV感染机制中的作用在很大程度上仍未得到解决。在这项研究中，我们产生了一个gH无效突变KSHV，并提供证据表明，缺乏gH表达不影响病毒颗粒的组装或出口。使用gH-无效突变体，我们表明，gH是必不可少的KSHV感染的上皮细胞，内皮细胞和成纤维细胞在体外。这表明gH是开发KSHV预防性疫苗以预防初始病毒感染的重要靶标。
Kaposi sarcoma-associated herpesvirus (KSHV) is an emerging pathogen and is the causative infectious agent of Kaposi sarcoma and two malignancies of B cell origin. To date, there is no licensed KSHV vaccine. Development of an effective vaccine against KSHV continues to be limited by a poor understanding of how the virus initiates acute primary infection in vivo in diverse human cell types. The role of glycoprotein H (gH) in herpesvirus entry mechanisms remains largely unresolved. To characterize the requirement for KSHV gH in the viral life cycle and in determination of cell tropism, we generated and characterized a mutant KSHV in which expression of gH was abrogated. Using a bacterial artificial chromosome containing a complete recombinant KSHV genome and recombinant DNA technology, we inserted stop codons into the gH coding region. We used electron microscopy to reveal that the gH-null mutant virus assembled and exited from cells normally, compared to wild-type virus. Using purified virions, we assessed infectivity of the gH-null mutant in diverse mammalian cell types in vitro. Unlike wild-type virus or a gH-containing revertant, the gH-null mutant was unable to infect any of the epithelial, endothelial, or fibroblast cell types tested. However, its ability to infect B cells was equivocal and remains to be investigated in vivo due to generally poor infectivity in vitro. Together, these results suggest that gH is critical for KSHV infection of highly permissive cell types, including epithelial, endothelial, and fibroblast cells.IMPORTANCE All homologues of herpesvirus gH studied to date have been implicated in playing an essential role in viral infection of diverse permissive cell types. However, the role of gH in the mechanism of KSHV infection remains largely unresolved. In this study, we generated a gH-null mutant KSHV and provided evidence that deficiency of gH expression did not affect viral particle assembly or egress. Using the gH-null mutant, we showed that gH was indispensable for KSHV infection of epithelial, endothelial, and fibroblast cells in vitro. This suggests that gH is an important target for the development of a KSHV prophylactic vaccine to prevent initial viral infection.