Pacitti A F, Gentsch J R
J Virol. 1987 May;61(5):1407-15. doi: 10.1128/JVI.61.5.1407-1415.1987.
The interaction of mammalian reoviruses with sialylated glycoproteins was studied and found to be highly serotype specific in that attachment of type 3 Dearing reovirus to murine L cell receptors could be strongly inhibited by bovine submaxillary mucin (BSM), fetuin, and alpha 1 acid glycoprotein, albeit at different efficiencies, whereas attachment of type 1 Lang reovirus was inhibited only by fetuin. We subsequently demonstrated, by using reassortants between type 3 and 1 reoviruses, that inhibition of reovirus attachment to cell receptors was specified by the viral attachment protein gene S1. Using a solid-phase binding assay, we further demonstrated that the ability of reovirus type 3 or reassortant 1HA3 and the inability of reovirus type 1 or reassortant 3HA1 to bind avidly to BSM was a property of the viral S1 genome segment and required the presence of sialic acid residues on BSM oligosaccharides. Taken together, these results demonstrated that there is a serotype-specific difference in the ability of the reovirus attachment protein, sigma 1, to interact with sialylated oligosaccharides of glycoproteins. Interaction of reovirus type 3 with sialylated oligosaccharides of BSM is dramatically affected by the degree of O-acetylation of their sialic acid residues, as indicated by the findings that chemical removal of O-acetyl groups stimulated reovirus type 3 attachment to BSM, whereas preferential removal of residues lacking or possessing reduced amounts of O-acetyl groups per sialic acid molecule with Vibrio cholerae sialidase abolished binding. We also demonstrated that BSM was 10 times more potent in inhibiting attachment of infectious reovirus to L cells than was V. cholerae-treated BSM. The results are consistent with the hypothesis that sialylated oligosaccharides on host cells or erythrocytes may act as binding sites or components of binding sites for type 3 reovirus through a specific interaction with the virus attachment protein.
对哺乳动物呼肠孤病毒与唾液酸化糖蛋白的相互作用进行了研究，发现其具有高度血清型特异性。具体而言，3型迪林呼肠孤病毒与小鼠L细胞受体的结合可被牛颌下粘蛋白（BSM）、胎球蛋白和α1酸性糖蛋白强烈抑制，尽管抑制效率不同；而1型朗呼肠孤病毒的结合仅被胎球蛋白抑制。随后，我们通过使用3型和1型呼肠孤病毒之间的重配体证明，呼肠孤病毒与细胞受体结合的抑制作用由病毒附着蛋白基因S1决定。使用固相结合试验，我们进一步证明，3型呼肠孤病毒或重配体1HA3与BSM紧密结合的能力以及1型呼肠孤病毒或重配体3HA1无法与BSM紧密结合的特性是病毒S1基因组片段的属性，并且需要BSM寡糖上存在唾液酸残基。综上所述，这些结果表明，呼肠孤病毒附着蛋白σ1与糖蛋白的唾液酸化寡糖相互作用的能力存在血清型特异性差异。3型呼肠孤病毒与BSM的唾液酸化寡糖的相互作用受到其唾液酸残基O-乙酰化程度的显著影响，如下述发现所示：化学去除O-乙酰基团会刺激3型呼肠孤病毒与BSM的结合，而用霍乱弧菌唾液酸酶优先去除每个唾液酸分子缺乏或具有较少O-乙酰基团的残基则会消除结合。我们还证明，BSM在抑制感染性呼肠孤病毒与L细胞结合方面的效力比经霍乱弧菌处理的BSM高10倍。这些结果与以下假设一致：宿主细胞或红细胞上的唾液酸化寡糖可能通过与病毒附着蛋白的特异性相互作用，作为3型呼肠孤病毒的结合位点或结合位点的组成部分。
