Glasner Dustin R, Ratnasiri Kalani, Puerta-Guardo Henry, Espinosa Diego A, Beatty P Robert, Harris Eva
Division of Infectious Diseases and Vaccinology, School of Public Health, University of California, Berkeley, CA, United States of America.
PLoS Pathog. 2017 Nov 9;13(11):e1006673. doi: 10.1371/journal.ppat.1006673. eCollection 2017 Nov.
Dengue virus (DENV) is the most prevalent, medically important mosquito-borne virus. Disease ranges from uncomplicated dengue to life-threatening disease, characterized by endothelial dysfunction and vascular leakage. Previously, we demonstrated that DENV nonstructural protein 1 (NS1) induces endothelial hyperpermeability in a systemic mouse model and human pulmonary endothelial cells, where NS1 disrupts the endothelial glycocalyx-like layer. NS1 also triggers release of inflammatory cytokines from PBMCs via TLR4. Here, we examined the relative contributions of inflammatory mediators and endothelial cell-intrinsic pathways. In vivo, we demonstrated that DENV NS1 but not the closely-related West Nile virus NS1 triggers localized vascular leak in the dorsal dermis of wild-type C57BL/6 mice. In vitro, we showed that human dermal endothelial cells exposed to DENV NS1 do not produce inflammatory cytokines (TNF-α, IL-6, IL-8) and that blocking these cytokines does not affect DENV NS1-induced endothelial hyperpermeability. Further, we demonstrated that DENV NS1 induces vascular leak in TLR4- or TNF-α receptor-deficient mice at similar levels to wild-type animals. Finally, we blocked DENV NS1-induced vascular leak in vivo using inhibitors targeting molecules involved in glycocalyx disruption. Taken together, these data indicate that DENV NS1-induced endothelial cell-intrinsic vascular leak is independent of inflammatory cytokines but dependent on endothelial glycocalyx components.
登革病毒（DENV）是最常见且在医学上具有重要意义的蚊媒病毒。其引发的疾病范围从无并发症的登革热到危及生命的疾病，特征为内皮功能障碍和血管渗漏。此前，我们证明登革病毒非结构蛋白1（NS1）在系统性小鼠模型和人肺内皮细胞中可诱导内皮细胞高通透性，其中NS1会破坏内皮糖萼样层。NS1还通过Toll样受体4（TLR4）触发外周血单核细胞（PBMC）释放炎性细胞因子。在此，我们研究了炎性介质和内皮细胞内在途径的相对作用。在体内，我们证明DENV NS1而非密切相关的西尼罗河病毒NS1会在野生型C57BL/6小鼠的背部真皮引发局部血管渗漏。在体外，我们发现暴露于DENV NS1的人真皮内皮细胞不会产生炎性细胞因子（肿瘤坏死因子-α、白细胞介素-6、白细胞介素-8），并且阻断这些细胞因子并不影响DENV NS1诱导的内皮细胞高通透性。此外，我们证明DENV NS1在TLR4或肿瘤坏死因子-α受体缺陷型小鼠中诱导血管渗漏的程度与野生型动物相似。最后，我们在体内使用靶向参与糖萼破坏的分子的抑制剂来阻断DENV NS1诱导的血管渗漏。综上所述，这些数据表明DENV NS1诱导的内皮细胞内在性血管渗漏不依赖于炎性细胞因子，而是依赖于内皮糖萼成分。
