2006年VOA标准英语-Vaccine Eliminates Allergy Symptoms

By Jessica Berman
Washington
05 October 2006

U.S. researchers have developed a vaccine¹ that offers protection against a common allergy² trigger in the United States known as ragweed. Scientists say the development has the potential to guard against any number of inflammatory diseases. 

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Ragweed plant

Ragweed, which causes hay fever, is the number-one cause of allergic³ symptoms during the autumn season in the United States.

Hay fever produces sneezing, an itchy, runny nose and watery⁴ eyes. The problem is worst in the eastern and midwestern United States. The symptoms are triggered by pollen⁵ from the yellow flowering ragweed.

The allergic sufferer, according to expert Peter Creticos, produces too much of an antibody called I.g.E. This triggers an excessive immune response to otherwise harmless substances such as pollen.

"The question is, 'Can you turn off that I.g.E.-mediated allergic process?' With traditional immuno-therapy, you can accomplish that. But it takes years and years," he said.

That would be an average of four to five years of going to an allergist for weekly injections to become fully⁶ immune to the ravages⁷ of ragweed pollen.

But Creticos, an associate professor of medicine at Johns Hopkins University in the eastern U.S. state of Maryland, and colleagues have conducted trials of an experimental vaccine that achieves the same level of protection in just six injections.

In a study published in the New England Journal of Medicine, a team led by Creticos reports the vaccine virtually eliminated ragweed symptoms in 14 severely⁸ affected⁹ individuals between the ages of 23 and 60.

The drug, administered in six weekly shots before the 2001 ragweed season, protected the study participants that year and through the 2002 ragweed season.

Investigators¹⁰ do not know yet whether the vaccine will offer protection beyond two years, but they think it will.

The vaccine was developed by Dynavax Technologies of Berkeley, California, which funded the clinical trials.

Co-author David Broide of the University of California in San Diego says the drug acts as a decoy to deceive the immune system of allergy sufferers.

"Bacteria activate¹¹ a protective-host immune response. And we have taken advantage of this by tagging the allergen with this little piece of bacterial¹² DNA¹³, which is not infectious, and which results in the immune system being fooled into thinking that they are seeing a bacteria instead of an allergen," he said. "And they do not bring up the allergic immune response."

Broide says the vaccine will not be available for at least another two years.

In time, researchers hope to use the DNA technology to create vaccines¹⁴ against grass pollen, cat dander and dust, as well as more serious diseases such as hepatitis.

1 vaccine   

n.牛痘苗，疫苗；adj.牛痘的，疫苗的

参考例句：

• The polio vaccine has saved millions of lives.脊髓灰质炎疫苗挽救了数以百万计的生命。
• She takes a vaccine against influenza every fall.她每年秋季接种流感疫苗。

2 allergy   

n.(因食物、药物等而引起的)过敏症

参考例句：

• He developed an allergy to pollen.他对花粉过敏。
• The patient had an allergy to penicillin.该患者对青霉素过敏。

3 allergic   

adj.过敏的，变态的

参考例句：

• Alice is allergic to the fur of cats.艾丽斯对猫的皮毛过敏。
• Many people are allergic to airborne pollutants such as pollen.许多人对空气传播的污染物过敏，比如花粉。

4 watery   

adj.有水的，水汪汪的；湿的，湿润的

参考例句：

• In his watery eyes there is an expression of distrust.他那含泪的眼睛流露出惊惶失措的神情。
• Her eyes became watery because of the smoke.因为烟熏，她的双眼变得泪汪汪的。

5 pollen   

n.[植]花粉

参考例句：

• Hummingbirds have discovered that nectar and pollen are very nutritious.蜂鸟发现花蜜和花粉是很有营养的。
• He developed an allergy to pollen.他对花粉过敏。

6 fully   

adv.完全地，全部地，彻底地；充分地

参考例句：

• The doctor asked me to breathe in,then to breathe out fully.医生让我先吸气，然后全部呼出。
• They soon became fully integrated into the local community.他们很快就完全融入了当地人的圈子。

7 ravages   

劫掠后的残迹，破坏的结果，毁坏后的残迹

参考例句：

• the ravages of war 战争造成的灾难
• It is hard for anyone to escape from the ravages of time. 任何人都很难逃避时间的摧残。

8 severely   

adv.严格地；严厉地；非常恶劣地

参考例句：

• He was severely criticized and removed from his post.他受到了严厉的批评并且被撤了职。
• He is severely put down for his careless work.他因工作上的粗心大意而受到了严厉的批评。

9 affected   

adj.不自然的，假装的

参考例句：

• She showed an affected interest in our subject.她假装对我们的课题感到兴趣。
• His manners are affected.他的态度不自然。

10 investigators   

n.调查者，审查者( investigator的名词复数 )

参考例句：

• This memo could be the smoking gun that investigators have been looking for. 这份备忘录可能是调查人员一直在寻找的证据。
• The team consisted of six investigators and two secretaries. 这个团队由六个调查人员和两个秘书组成。 来自《简明英汉词典》

11 activate   

vt.使活动起来，使开始起作用

参考例句：

• We must activate the youth to study.我们要激励青年去学习。
• These push buttons can activate the elevator.这些按钮能启动电梯。

12 bacterial   

a.细菌的

参考例句：

• Bacterial reproduction is accelerated in weightless space. 在失重的空间，细菌繁殖加快了。
• Brain lesions can be caused by bacterial infections. 大脑损伤可能由细菌感染引起。

13 DNA   

(缩)deoxyribonucleic acid 脱氧核糖核酸

参考例句：

• DNA is stored in the nucleus of a cell.脱氧核糖核酸储存于细胞的细胞核里。
• Gene mutations are alterations in the DNA code.基因突变是指DNA密码的改变。

14 vaccines   

疫苗，痘苗( vaccine的名词复数 )

参考例句：

• His team are at the forefront of scientific research into vaccines. 他的小组处于疫苗科研的最前沿。
• The vaccines were kept cool in refrigerators. 疫苗放在冰箱中冷藏。