Li Tian-Cheng, Iwasaki Kenji, Katano Harutaka, Kataoka Michiyo, Nagata Noriyo, Kobayashi Kazumi, Mizutani Tetsuya, Takeda Naokazu, Wakita Takaji, Suzuki Tetsuro
Department of Virology II, National Institute of Infectious Diseases, Tokyo, Japan.
Institute for Protein Research, Osaka University, Osaka, Japan.
PLoS One. 2015 Feb 11;10(2):e0115646. doi: 10.1371/journal.pone.0115646. eCollection 2015.
In our recombinant baculovirus system, VP1 protein of merkel cell polyomavirus (MCPyV), which is implicated as a causative agent in Merkel cell carcinoma, was self-assembled into MCPyV-like particles (MCPyV-LP) with two different sizes in insect cells, followed by being released into the culture medium. DNA molecules of 1.5- to 5-kb, which were derived from host insect cells, were packaged in large, ~50-nm spherical particles but not in small, ~25-nm particles. Structure reconstruction using cryo-electron microscopy showed that large MCPyV-LPs are composed of 72 pentameric capsomeres arranged in a T = 7 icosahedral surface lattice and are 48 nm in diameter. The MCPyV-LPs did not share antigenic determinants with BK- and JC viruses (BKPyV and JCPyV). The VLP-based enzyme immunoassay was applied to investigate age-specific prevalence of MCPyV infection in the general Japanese population aged 1-70 years. While seroprevalence of MCPyV increased with age in children and young individuals, its seropositivity in each age group was lower compared with BKPyV and JCPyV.
在我们的重组杆状病毒系统中，默克尔细胞多瘤病毒（MCPyV）的VP1蛋白（被认为是默克尔细胞癌的病原体）在昆虫细胞中自组装成两种不同大小的MCPyV样颗粒（MCPyV-LP），随后释放到培养基中。源自宿主昆虫细胞的1.5至5 kb的DNA分子被包装在大约50 nm的大型球形颗粒中，而不是在大约25 nm的小型颗粒中。使用冷冻电子显微镜进行的结构重建表明，大型MCPyV-LP由72个五聚体壳粒组成，排列成T = 7的二十面体表面晶格，直径为48 nm。MCPyV-LP与BK病毒和JC病毒（BKPyV和JCPyV）没有共同的抗原决定簇。基于病毒样颗粒的酶免疫测定法用于调查1至70岁日本普通人群中MCPyV感染的年龄特异性流行情况。虽然MCPyV的血清阳性率在儿童和年轻人中随年龄增加，但与BKPyV和JCPyV相比，其在每个年龄组中的血清阳性率较低。
