Involvement of the matrix protein in attachment of porcine reproductive and respiratory syndrome virus to a heparinlike receptor on porcine alveolar macrophages
Involvement of the matrix protein in attachment of porcine reproductive and respiratory syndrome virus to a heparinlike receptor on porcine alveolar macrophages
复制标题
DOI：
10.1128/jvi.76.9.4312-4320.2002
复制
发表时间：
2002-05-01
影响因子：
5.4
通讯作者：
Pensaert, MB
中科院分区：
文献类型：
--
作者：
Delputte, PL;Vanderheijden, N;Pensaert, MB
猪繁殖与呼吸综合征病毒（PRRSV）对单核细胞-巨噬细胞系的分化良好的细胞具有非常有限的嗜性，这可能是由这些细胞上的特异性受体决定的。在这项研究中，肝素样分子对猪肺泡巨噬细胞（PAM）的PRRSV感染的重要性进行了测定。肝素与病毒相互作用，并减少PAM的感染高达92%或88%的美洲和欧洲型的PRRSV，分别。其他糖胺聚糖，类似于肝素，对感染没有显着影响，而肝素酶治疗PAM导致感染显着减少。感染动力学分析表明，PRRSV附着硫酸乙酰肝素发生在感染早期。观察到肝素敏感结合步骤，其在4 ℃下120 min后完全转化为肝素抗性结合。用肝素亲和层析和十二烷基硫酸钠-聚丙烯酰胺凝胶电泳（SDS-PAGE），观察到结构基质（M）和核衣壳（N）蛋白与肝素结合。非还原性SDS-PAGE显示，M主要以与糖蛋白GP的复合物的形式与肝素结合（5），而N蛋白以同二聚体的形式与肝素结合。GP（3）是欧洲型PRRSV的一种次要结构蛋白，不与肝素结合。由于N蛋白未暴露在病毒体表面，因此得出结论，结构M蛋白和M-GP（5）复合物有助于PRRSV附着在PAM上的肝素样受体上。这是第一个报告，确定了一个细胞表面肝素样受体PAM的PRRSV配体。
The porcine reproductive and respiratory syndrome virus (PRRSV) has a very restricted tropism for well-differentiated cells of the monocyte-macrophage lineage, which is probably determined by specific receptors on these cells. In this study, the importance of heparinlike molecules on porcine alveolar macrophages (PAM) for PRRSV infection was determined. Heparin interacted with the virus and reduced infection of PAM up to 92 or 88% for the American and European types of PRRSV, respectively. Other glycosaminoglycans, similar to heparin, had no significant effect on infection while heparinase treatment of PAM resulted in a significant reduction of the infection. Analysis of infection kinetics showed that PRRSV attachment to heparan sulfate occurs early in infection. A heparin-sensitive binding step was observed which converted completely into a heparin-resistant binding after 120 min at 4degreesC. Using heparin-affinity chromatography and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), it was observed that the structural matrix (M) and nucleocapsid (N) proteins attached to heparin. Nonreducing SDS-PAGE revealed that M bound to heparin mainly as a complex with glycoprotein GP(5) and that the N protein bound to heparin as a homodimer. GP(3), which was identified as a minor structural protein of European types of PRRSV, did not bind to heparin. Since the N protein is not exposed on the virion surface, it was concluded that the structural M protein and the M-GP(5), complex contribute to PRRSV attachment on a heparinlike receptor on PAM. This is the first report that identifies a PRRSV ligand for a cell surface heparinlike receptor on PAM.