Assessment of Seasonal Influenza A Virus-Specific CD4 T-Cell Responses to 2009 Pandemic H1N1 Swine-Origin Influenza A Virus
Assessment of Seasonal Influenza A Virus-Specific CD4 T-Cell Responses to 2009 Pandemic H1N1 Swine-Origin Influenza A Virus
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DOI：
10.1128/jvi.02226-09
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发表时间：
2010-04-01
影响因子：
5.4
通讯作者：
Kwok, William W.
中科院分区：
文献类型：
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作者：
Ge, Xinhui;Tan, Venus;Kwok, William W.
据报道，非常有限的证据表明人类对2009年H1N1猪源性流感病毒（S-OIV）的适应性免疫反应。我们研究了17个S-OIV肽同源的免疫显性CD 4 T表位血凝素（HA），神经氨酸酶（NA），核蛋白（NP），M1基质蛋白（MP），和PB 1的季节性H1N1毒株。我们得出结论，这17种S-OIV肽中的15种将诱导季节性流感病毒特异性T细胞的应答。其中，7个S-OIV序列与季节性流感病毒序列相同，而8个序列至少有一个氨基酸不保守。可离体检测识别源自这些S-OIV抗原的表位的T细胞。这些T细胞中的大多数表达记忆标记，尽管没有供体暴露于S-OIV。功能分析显示，这些S-OIV肽序列中的特定氨基酸差异不会影响或部分影响记忆T细胞应答。这些发现表明，如果没有保护性抗体应答，接种季节性甲型流感疫苗的个体仍可能受益于预先存在的交叉反应性记忆CD 4 T细胞，从而降低其对S-OIV感染的易感性。
Very limited evidence has been reported to show human adaptive immune responses to the 2009 pandemic H1N1 swine-origin influenza A virus (S-OIV). We studied 17 S-OIV peptides homologous to immunodominant CD4 T epitopes from hemagglutinin (HA), neuraminidase (NA), nuclear protein (NP), M1 matrix protein (MP), and PB1 of a seasonal H1N1 strain. We concluded that 15 of these 17 S-OIV peptides would induce responses of seasonal influenza virus-specific T cells. Of these, seven S-OIV sequences were identical to seasonal influenza virus sequences, while eight had at least one amino acid that was not conserved. T cells recognizing epitopes derived from these S-OIV antigens could be detected ex vivo. Most of these T cells expressed memory markers, although none of the donors had been exposed to S-OIV. Functional analysis revealed that specific amino acid differences in the sequences of these S-OIV peptides would not affect or partially affect memory T-cell responses. These findings suggest that without protective antibody responses, individuals vaccinated against seasonal influenza A may still benefit from preexisting cross-reactive memory CD4 T cells reducing their susceptibility to S-OIV infection.