美国科学60秒 SSS 2012-12-24
时间：2013-06-25 08:49:57
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（单词翻译）
Every fall, you need a new flu shot. That’s because today’s vaccines2 train your immune system to recognize specific strains of flu, indentified by two proteins on the virus’s coat, / and /. That’s where the H and N come from in H1N1.
Problem is those proteins are moving target. They mutate quickly. Once they do, your immune system can’t recognize them, and you’ve got something like the 2009 swine flu. A strain the flu shot never primed us to fight.
To make a more universal
vaccine1 that would work year after year, researchers focused on a smaller, more stable protein, called M2. In human’s strains, the protein has hardly changed since 1930s.
Researchers engineered the M2 vaccine and gave it to mice. Then they exposed the mice to
lethal3 dose of human, swine and bird flu. All the
vaccinated4 mice survived, their unlucky counterparts did not. The research appears in journal
Molecular5 Therapy.
A good
seasonal6 flu vaccine will still beat the M2 vaccine, but if the M2 give us insurance against a surprise strain, well, it might be worth a shot.
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