Kimura T, Gollins S W, Porterfield J S
J Gen Virol. 1986 Nov;67 ( Pt 11):2423-33. doi: 10.1099/0022-1317-67-11-2423.
The interaction between the flavivirus West Nile virus (WNV) and cells of the mouse macrophage-like cell line, P388D1, was assayed by transmission electron microscopy, by following the association of [35S]methionine-labelled virus with cells, and by using a radiobinding assay with an 125I-labelled F(ab')2 fragment of a monoclonal antibody directed against the major viral envelope surface glycoprotein. Using electron microscopy, both fusion and endocytosis were observed at pH 6.4, but at pH 8.0 only endocytosis was observed. When 35S-labelled WNV was bound to the P388D1 cell surface at 0 degrees C, less virus eluted on warming to 37 degrees C at mildly acidic than at alkaline or neutral pH values. The monoclonal antibody fragment had an increased affinity for cell surface viral E glycoprotein after prebound WNV was warmed at mildly acidic pH values. It is proposed that the warming of cell-virus mixtures at low pH results in fusion with a consequent reduction in elution of virus and an increase in the recognition of cell surface-expressed viral envelope glycoprotein by labelled antibody.
通过透射电子显微镜、追踪[35S]甲硫氨酸标记的病毒与细胞的结合情况以及使用针对主要病毒包膜表面糖蛋白的单克隆抗体的125I标记F(ab')2片段进行放射性结合测定，对黄病毒西尼罗河病毒（WNV）与小鼠巨噬细胞样细胞系P388D1的细胞之间的相互作用进行了分析。利用电子显微镜观察到，在pH 6.4时融合和内吞作用均有发生，但在pH 8.0时仅观察到内吞作用。当35S标记的WNV在0℃与P388D1细胞表面结合时，在温和酸性条件下升温至37℃时洗脱的病毒比在碱性或中性pH值条件下少。在温和酸性pH值下将预先结合的WNV升温后，单克隆抗体片段对细胞表面病毒E糖蛋白的亲和力增加。有人提出，在低pH值下将细胞-病毒混合物升温会导致融合，从而使病毒洗脱减少，并且标记抗体对细胞表面表达的病毒包膜糖蛋白的识别增加。
