Gaunt Eleanor, Wise Helen M, Zhang Huayu, Lee Lian N, Atkinson Nicky J, Nicol Marlynne Quigg, Highton Andrew J, Klenerman Paul, Beard Philippa M, Dutia Bernadette M, Digard Paul, Simmonds Peter
Infection and Immunity Division, Roslin Institute, University of Edinburgh, Edinburgh, United Kingdom.
Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom.
Elife. 2016 Feb 16;5:e12735. doi: 10.7554/eLife.12735.
Previously, we demonstrated that frequencies of CpG and UpA dinucleotides profoundly influence the replication ability of echovirus 7 (Tulloch et al., 2014). Here, we show that that influenza A virus (IAV) with maximised frequencies of these dinucleotides in segment 5 showed comparable attenuation in cell culture compared to unmodified virus and a permuted control (CDLR). Attenuation was also manifested in vivo, with 10-100 fold reduced viral loads in lungs of mice infected with 200PFU of CpG-high and UpA-high mutants. However, both induced powerful inflammatory cytokine and adaptive (T cell and neutralising antibody) responses disproportionate to their replication. CpG-high infected mice also showed markedly reduced clinical severity, minimal weight loss and reduced immmunopathology in lung, yet sterilising immunity to lethal dose WT challenge was achieved after low dose (20PFU) pre-immunisation with this mutant. Increasing CpG dinucleotide frequencies represents a generic and potentially highly effective method for generating safe, highly immunoreactive vaccines.
此前，我们证明了CpG和UpA二核苷酸的频率会深刻影响埃可病毒7的复制能力（Tulloch等人，2014年）。在此，我们表明，第5节段中这些二核苷酸频率最大化的甲型流感病毒（IAV）与未修饰病毒和置换对照（CDLR）相比，在细胞培养中表现出相当的减毒效果。减毒在体内也有体现，感染200PFU的高CpG和高UpA突变体的小鼠肺部病毒载量降低了10至100倍。然而，两者都引发了强大的炎性细胞因子和适应性（T细胞和中和抗体）反应，与其复制情况不成比例。高CpG感染的小鼠临床严重程度也显著降低，体重减轻最小，肺部免疫病理学减轻，然而，用该突变体低剂量（20PFU）预免疫后，对致死剂量野生型攻击实现了无菌免疫。增加CpG二核苷酸频率是一种通用且可能非常有效的生成安全、高免疫反应性疫苗的方法。
