Antibody epitopes on the neuraminidase of a recent H3N2 influenza virus (A/memphis/31/98)
Antibody epitopes on the neuraminidase of a recent H3N2 influenza virus (A/memphis/31/98)
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DOI：
10.1128/jvi.76.23.12274-12280.2002
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发表时间：
2002-12-01
影响因子：
5.4
通讯作者：
Air, GM
中科院分区：
文献类型：
--
作者：
Gulati, U;Hwang, CC;Air, GM
本文报道了抗悉尼样流感病毒（A/孟菲斯/31/98，H3 N2）神经氨酸酶（NA）的单克隆抗体在A/NWS/33（HA）-A/Mem/31/98（NA）（H1 N2）中的特性，以及由这些单克隆抗体选择的九种逃逸突变体。五种抗体使用相同的重链VDJ基因，并且可能不是独立的。另一种抗体Mem 5使用相同的V-H和J基因，具有不同的D基因和不同的同种型。由这些抗体选择的逃逸突变体中的序列变化发生在NA的两个环中，在氨基酸198、199、220或221处。这些氨基酸位于NA单体的与N9和早期N2 NA中发现的主要表位相反的一侧。与野生型病毒相比，在198处具有变化的逃逸突变体具有降低的NA活性。Asp][98指向底物结合口袋，我们以前发现这种氨基酸的定点突变导致酶活性的丧失（M。R.伦茨河，巴西-地G.韦伯斯特和G. M. Air，Biochemistry 26：5351-5358，1987）。与野生型NA相比，在残基199、220或221处的突变没有显著改变NA活性。与Mem/98 NA复合的Mem 5 Fab的3.5埃结构显示Mem 5抗体在由其它抗体选择的逃逸突变位点处结合。
We have characterized monoclonal antibodies raised against the neuraminidase (NA) of a Sydney-like influenza virus (A/Memphis/31/98, H3N2) in a reassortant virus A/NWS/33(HA)-A/Mem/31/98(NA) (H1N2) and nine escape mutants selected by these monoclonal antibodies. Five of the antibodies use the same heavy chain VDJ genes and may not be independent. Another antibody, Mem5, uses the same V-H and J genes with a different D gene and different isotype. Sequence changes in escape mutants selected by these antibodies occur in two loops of the NA, at amino acid 198, 199, 220, or 221. These amino acids are located on the opposite side of the NA monomer to the major epitopes found in N9 and early N2 NAs. Escape mutants with a change at 198 have reduced NA activity compared to the wild-type virus. Asp][98 points toward the substrate binding pocket, and we had previously found that a site-directed mutation of this amino acid resulted in a loss of enzyme activity (M. R. Lentz, R. G. Webster, and G. M. Air, Biochemistry 26:5351-5358, 1987). Mutations at residue 199, 220, or 221 did not alter the NA activity significantly compared to that of wild-type NA. A 3.5-Angstrom structure of Mem5 Fab complexed with the Mem/98 NA shows that the Mem5 antibody binds at the sites of escape mutation selected by the other antibodies.