Sci Trans Med:易受骗的免疫细胞让通用流感疫苗遥遥无期

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开发通用流感疫苗的难度可能比科学家以前认为的高得多，原因是我们的免疫系统太容易受骗。流感病毒以擅长突变著称，它通过改变自己躲避免疫细胞的探测。因为流感的易变性，我们每年都需要开发新的疫苗而不能依赖免疫系统对去年流感的记忆。

发表在《Science Translational Medicine》上的一项研究指出，我们的免疫系统有潜力发现和对抗所有的病毒变种，但被骗只打击特定的病毒变种。芝加哥大学的研究人员让21名被试暴露在2009 H1N1病毒下，检查他们的免疫反应，观察生产抗体的B细胞。抗体是通过检查流感病毒的血球凝集素（(HA）头部将其识别出来。而HA头部会频繁变异，从而躲避抗体。但研究人员发现，免疫系统天生会生产出发现所有病毒变异的跟踪抗体，但茎部抗体（stalk antibodies）会被头部抗体（head antibodies）驱逐，原因是这些抗体的打击更精确，而跟踪抗体精度不高。由于跟踪抗体的低效和低精度，免疫系统更偏爱激活B细胞去生产头部绑定抗体。

来源：生物360

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Immune history profoundly affects broadly protective B cell responses to influenza

Sarah F. Andrews1, Yunping Huang1, Kaval Kaur1,2, Lyubov I. Popova1, Irvin Y. Ho1, Noel T. Pauli1,2, Carole J. Henry Dunand1, William M. Taylor1, Samuel Lim1, Min Huang1, Xinyan Qu1, Jane-Hwei Lee1, Marlene Salgado-Ferrer1, Florian Krammer3, Peter Palese3,4, Jens Wrammert5, Rafi Ahmed5 and Patrick C. Wilson

Abstract
Generating a broadly protective influenza vaccine is critical to global health. Understanding how immune memory influences influenza immunity is central to this goal. We undertook an in-depth study of the B cell response to the pandemic 2009 H1N1 vaccine over consecutive years. Analysis of monoclonal antibodies generated from vaccine-induced plasmablasts demonstrated that individuals with low preexisting serological titers to the vaccinating strain generated a broadly reactive, hemagglutinin (HA) stalk–biased response. Higher preexisting serum antibody levels correlated with a strain-specific HA head–dominated response. We demonstrate that this HA head immunodominance encompasses poor accessibility of the HA stalk epitopes. Further, we show polyreactivity of HA stalk–reactive antibodies that could cause counterselection of these cells. Thus, preexisting memory B cells against HA head epitopes predominate, inhibiting a broadly protective response against the HA stalk upon revaccination with similar strains. Consideration of influenza exposure history is critical for new vaccine strategies designed to elicit broadly neutralizing antibodies.

http://stm.sciencemag.org/content/7/316/316ra192.full

Biodog

stalk antibodies应翻译为“茎部抗体‘更恰当，有的文献上也叫stem antibody！

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Biodog 发表于 2015-12-7 22:00
stalk antibodies应翻译为“茎部抗体‘更恰当，有的文献上也叫stem antibody！

是的，转载的时候没注意，先已改正。