Abstract：
Dengue virus (DENV) is a considerable public health threat affecting millions of people globally. Vaccines for dengue are an important strategy to reduce the disease burden. We expressed capsid (C2) and envelope domain III of dengue virus serotype 2 (2EDIII) separately in the silkworm expression system. We conjugated them employing the monomeric streptavidin (mSA2) and biotin affinity to display the antigenic 2EDIII on the C2-forming capsid-like particle (CLP). Purified 2EDIII-displaying C2 (CLP/2EDIII) was immunogenic in BALB/c mice, eliciting neutralizing antibodies confirmed by a single-round infectious particle (SRIP) neutralization assay. Th1 cytokine levels were upregulated for the CLP/2EDIII group, and the anti-inflammatory IL-10 and pro-inflammatory IL-6 cytokine levels were also raised compared to the 2EDIII and the control groups. Elevated cytokine levels for CLP/2EDIII indicate the importance of displaying the 2EDIII as CLP/2EDIII rather than as an individual subunit. This study is the first to express the C2 protein as self-assembling CLP in vivo and 2EDIII separately in the silkworm expression system and conjugate them to form a monovalent CLP. Thus, this CLP/2EDIII display method may pave the way for an efficient tetravalent dengue vaccine candidate.
摘要：
登革热病毒(DENV)是影响全球数百万人的相当大的公共卫生威胁。登革热疫苗是减轻疾病负担的重要策略。我们在家蚕表达系统中分别表达了登革病毒2型（2EDIII）的衣壳（C2）和包膜结构域III。我们使用单体链霉亲和素（mSA2）和生物素亲和力将它们缀合，以在形成C2的衣壳样颗粒（CLP）上显示抗原性2EDIII。纯化的2EDIII显示C2（CLP/2EDIII）在BALB/c小鼠中具有免疫原性，通过单轮感染性颗粒（SRIP）中和测定证实的中和抗体。CLP/2EDIII组的Th1细胞因子水平上调，与2EDIII和对照组相比，抗炎IL-10和促炎IL-6细胞因子水平也升高。CLP/2EDIII的细胞因子水平升高表明将2EDIII展示为CLP/2EDIII而不是作为单个亚基的重要性。本研究首次将C2蛋白作为自组装CLP在体内表达，并在家蚕表达系统中分别表达2EDIII，并将它们偶联形成单价CLP。因此，这种CLP/2EDIII展示方法可能为高效的四价登革热候选疫苗铺平道路。
