Design of Escherichia coli-Expressed Stalk Domain Immunogens of H1N1 Hemagglutinin That Protect Mice from Lethal Challenge
Design of Escherichia coli-Expressed Stalk Domain Immunogens of H1N1 Hemagglutinin That Protect Mice from Lethal Challenge
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DOI：
10.1128/jvi.01429-12
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发表时间：
2012-12-01
影响因子：
5.4
通讯作者：
Liang, Xiaoping
中科院分区：
文献类型：
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作者：
Bommakanti, Gayathri;Lu, Xianghan;Liang, Xiaoping
流感病毒表面的血凝素蛋白（HA）对于病毒进入宿主细胞至关重要。 HA 的 HA1 亚基也是中和抗体的主要靶标。 HA2 亚基在病毒粒子表面的暴露较少，并且比 HA1 更保守。我们之前设计了一种源自 H3N2 A/HK/68 病毒序列的基于 HA2 的免疫原。在本研究中，我们报告了 H1N1 亚型 (PR/8/34) 的基于 HA2 的免疫原的设计。这种免疫原 (H1HA0HA6) 及其环状排列突变体 (H1HA6) 折叠良好，可提供针对同源病毒攻击的完整保护。免疫小鼠的抗血清与不同品系和亚型的HA蛋白表现出交叉反应性。虽然在传统的中和测定中没有观察到中和作用，但免疫豚鼠的血清与广泛中和抗体 CR6261 竞争与重组 Viet/04 HA 蛋白的结合，表明 CR6261 样抗体是由免疫原引发的。来自季节性 H1N1 毒株 (A/NC/20/99) 和最近大流行毒株 (A/Cal/07/09) 的干域免疫原提供了针对 A/PR/8/34 病毒攻击的交叉保护。因此，含有HA2的干结构域免疫原有可能提供亚型特异性保护。
The hemagglutinin protein (HA) on the surface of influenza virus is essential for viral entry into the host cells. The HA1 subunit of HA is also the primary target for neutralizing antibodies. The HA2 subunit is less exposed on the virion surface and more conserved than HA1. We have previously designed an HA2-based immunogen derived from the sequence of the H3N2 A/HK/68 virus. In the present study, we report the design of an HA2-based immunogen from the H1N1 subtype (PR/8/34). This immunogen (H1HA0HA6) and its circular permutant (H1HA6) were well folded and provided complete protection against homologous viral challenge. Antisera of immunized mice showed cross-reactivity with HA proteins of different strains and subtypes. Although no neutralization was observable in a conventional neutralization assay, sera of immunized guinea pigs competed with a broadly neutralizing antibody, CR6261, for binding to recombinant Viet/04 HA protein, suggesting that CR6261-like antibodies were elicited by the immunogens. Stem domain immunogens from a seasonal H1N1 strain (A/NC/20/99) and a recent pandemic strain (A/Cal/07/09) provided cross-protection against A/PR/8/34 viral challenge. HA2-containing stem domain immunogens therefore have the potential to provide subtype-specific protection.