From VOA Learning English, this is the Health Report.
Infection by the influenza virus may be more complex than scientists first thought. Researchers in the United States reported recently that the virus appears to disarm the body's first line of defense against disease.
When the flu virus attacks, the body's natural defenses produce white blood cells. The cells make antibodies design to linkup to the invading microorganism, neutralize it, and in that way, prevent or at least lessen infection. The special cells also keep a memory of the invader so that the natural defenses can fight it again if the individual is re-infected. That is the traditional understanding of how the body fights the flu virus.
Now, biologists have discovered how the virus can disarm those white blood cells, known as B cells. Hidde Ploegh led the team of researchers, he is with the Whitehead Institute for Biomedical Research in Cambridge, Massachusetts.
Studies with genetically-bred mice suggest the flu virus enters the B cells and interferes with the production of antibodies, this can kill the cells and the body's first line of defense.
If true, says Mr Ploegh, the process of infection may be more complex than scientists have thought.
"And so we think that this really provides a new window on how the virus goes about its business. It may have implications in terms of explaining why certain strains of flu cause a nastier version of the disease than others," said Ploegh.
Normally, the frontline antibodies occupy lung cells to protect the body against future viral invasion through breathing.
But the flu virus having disabled the antibodies, may instead target lung cells. In that way, the virus blocks the antibody's ability to remember the deadly invader, and labeling the virus to launch an attack on the body's defenses.
"So this suggests that the initial encounter of the very type of white blood cell that we think defends us against the virus may be taken out by this initial wave of infection," said Ploegh.
By neutralizing an interfering with the body's 'front line troops', Mr Ploegh says the flu virus has more time to reproduce and establish itself in the cells, that keeps the immune system from developing a second line of defense.
A report on how influenza overcomes the body's immune system was published in the journal Nature.
And that's the Health Report from VOA Learning English. You can read, listen and learn English with health news and more on our website learningenglish.voanews.com. You can also watch our captioned videos at the VOA Learning English channel on YouTube. I'm Milagros Ardin.
1.influenza n. [内科] 流行性感冒（简写flu）；家畜流行性感冒
This attack of influenza has crocked him up.
2.disarm vt. 解除武装；裁军；缓和
The police disarmed the remaining suspects.
3.antibody n. [免疫] 抗体
If the antibody reacted, the blood was tainted and should be discarded.
4.reproduce vt. 复制；再生；生殖；使…在脑海中重现 vi. 复制；繁殖
Lobsters can reproduce a lost limb.
1.By neutralizing an interfering with the body's 'front line troops',
interfere with 干扰，干涉；妨碍；触动或弄坏；乱动；
Complete absorption in sports interfered with his studies.
I am not going to be interfered with.
2.that keeps the immune system from developing a second line of defense.
keep from 隐瞒；阻止；抑制
The heavy rain can't keep me from going out.
You should keep from doing anything rash.
当流感病毒来袭时，人体的自然防御能产生白细胞，这些细胞创造意在连接这些入侵微生物的抗体并将之中性化，这样就能阻止或者至少减轻感染。这些特殊的细胞还能记住入侵者，这样当个人再次感染时自然防御就能再次与之相斗争 。这是传统上对身体对付流感病毒的理解 。
现在，生物学家发现了这种病毒如何瓦解这些名为B细胞的白细胞。Hidde Ploegh是研究组负责人，他就职于马萨诸塞州剑桥怀海德生物医学研究所 。