Mercado-Curiel Ricardo F, Esquinca-Avilés Héctor Armando, Tovar Rosalinda, Díaz-Badillo Alvaro, Camacho-Nuez Minerva, Muñoz María de Lourdes
Department of Genetics and Molecular Biology, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional. Ave. Instituto Politécnico Nacional 2508 Col San Pedro Zacatenco, C.P. 07360, México, D. F., México.
BMC Microbiol. 2006 Oct 2;6:85. doi: 10.1186/1471-2180-6-85.
Dengue viruses (DENV) attach to the host cell surface and subsequently enter the cell by receptor-mediated endocytosis. Several primary and low affinity co-receptors for this flavivirus have been identified. However, the presence of these binding molecules on the cell surface does not necessarily render the cell susceptible to infection. Determination of which of them serve as bona fide receptors for this virus in the vector may be relevant to treating DENV infection and in designing control strategies.
(1) Overlay protein binding assay showed two proteins with molecular masses of 80 and 67 kDa (R80 and R67). (2) Specific antibodies against these two proteins inhibited cell binding and infection. (3) Both proteins were bound by all four serotypes of dengue virus. (4) R80 and R67 were purified by affinity chromatography from Ae. aegypti mosquito midguts and from Ae albopictus C6/36 cells. (5) In addition, a protein with molecular mass of 57 kDa was purified by affinity chromatography from the midgut extracts. (6) R80 and R67 from radiolabeled surface membrane proteins of C6/36 cells were immunoprecipitated by antibodies against Ae. aegypti midgut.
Our results strongly suggest that R67 and R80 are receptors for the four serotypes of dengue virus in the midgut cells of Ae. aegypti and in C6/36 Ae. albopictus cells.
登革病毒（DENV）附着于宿主细胞表面，随后通过受体介导的内吞作用进入细胞。已鉴定出该黄病毒的几种初级和低亲和力共受体。然而，这些结合分子在细胞表面的存在并不一定使细胞易受感染。确定它们中的哪些在载体中作为该病毒的真正受体可能与治疗登革病毒感染和设计控制策略有关。
（1）覆盖蛋白结合试验显示出两种分子量分别为80 kDa和67 kDa的蛋白质（R80和R67）。（2）针对这两种蛋白质的特异性抗体抑制细胞结合和感染。（3）这两种蛋白质均被登革病毒的所有四种血清型结合。（4）通过亲和色谱法从埃及伊蚊中肠和白纹伊蚊C6/36细胞中纯化出R80和R67。（5）此外，通过亲和色谱法从肠提取物中纯化出一种分子量为57 kDa的蛋白质。（6）来自C6/36细胞放射性标记表面膜蛋白的R80和R67被抗埃及伊蚊中肠的抗体免疫沉淀。
我们的结果有力地表明，R67和R80是埃及伊蚊中肠细胞和白纹伊蚊C6/36细胞中登革病毒四种血清型的受体。
