Antigenic reactivity of pandemic influenza (H1N1) 2009 viruses from UK (n = 227).

Viruses are grouped according with amino acid signature changes described in Figures 2 and 3. Substitutions located within the signal peptide were not considered.aAmino acid changes are described using as reference the sequence of A/California/07/09.bRefers to 4-fold dilutions of antiserum against A/California/07/09. Viruses with >4-fold reduced antigenic reactivity are considered as “low reactors”. Compared with the vaccine strain antiserum, the titres with A/England/195/2009 antiserum were within one-fold of difference in most cases and all the pandemic viruses showed no reactivity against A/Brisbane/59/07 antiserum; therefore these results are not included in the analysis.cGroups where >50% of the viruses shows ≥4-fold reduced reactivity are highlighted in bold letter.

病毒根据图2和图3中所描述的氨基酸签名变化进行分组。位于信号肽内的替换并未被考虑。氨基酸变化以A/California/07/09序列为参照进行描述。针对A/California/07/09的血清抗体进行4倍稀释，病毒若抗原反应性降低超过4倍则被视为“低反应者”。与疫苗株的血清抗体相比，大多数情况下A/England/195/2009血清抗体的滴度与疫苗株相差一倍以内，所有大流行病毒对A/Brisbane/59/07血清抗体均无反应性；因此，这些结果未纳入分析。其中，超过50%的病毒显示抗原反应性降低≥4倍的组别以粗体字母突出显示。