Coxsackievirus B4 (CV-B4) is suspected to be an environmental factor that has the intrinsic capacity to damage the pancreatic beta cells and therefore causes insulitis and type 1 diabetes (T1D). Although vaccination against CV-B4 could reduce the incidence of this chronic auto-immune disease, there is currently no therapeutic reagent or vaccine in clinical use. By the employment of the Bac-to-Bac® vector system to express the major viral capsid protein, we contributed towards the development of a CV-B4 vaccine by producing CV-B4 virus-like particles (VLPs) from recombinant baculovirus in infected insect cells. In fact Western blot and Immunofluorescence analysis detected the viral protein 1 (VP1) in the cells resulting from the construction of a recombinant bacmid DNA carrying the key immunogenic protein then transfected in the insect cells. Sucrose gradient ultracentrifugation fractions of the infected cell lysates contained the recombinant protein and the electron microscopy demonstrated the presence of VLPs in these sucrose fractions. This study clearly shows for the first time the expression of CVB4 VP1 structure protein alone can form VLPs in the baculovirus-infected insect cell keeping conserved both characteristics and morphology.

中文翻译：

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由表达主要衣壳蛋白的重组杆状病毒-昆虫细胞系统产生的柯萨奇病毒B4病毒样颗粒VLP的表征。

柯萨奇病毒B4（CV-B4）被怀疑是一种具有破坏胰腺β细胞的内在能力的环境因素，因此会导致胰岛炎和1型糖尿病（T1D）。尽管针对CV-B4的疫苗接种可以减少这种慢性自身免疫性疾病的发生率，但目前临床上没有治疗试剂或疫苗。通过使用Bac-to-Bac®载体系统表达主要的病毒衣壳蛋白，我们通过在感染昆虫中由重组杆状病毒生产CV-B4病毒样颗粒（VLP），为CV-B4疫苗的开发做出了贡献细胞。实际上，Western印迹和免疫荧光分析检测到细胞中的病毒蛋白1（VP1），该病毒蛋白是通过构建携带关键免疫原性蛋白的重组杆状病毒质粒DNA构建而成，然后将其转染到昆虫细胞中的。感染细胞裂解液的蔗糖梯度超速离心分离级分含有重组蛋白，电子显微镜显示这些蔗糖级分中存在VLP。这项研究清楚地表明，首次单独表达CVB4 VP1结构蛋白可以在杆状病毒感染的昆虫细胞中形成VLP，同时保持特征和形态。