发帖
每发1个新帖
可以获得0.5个丁当奖励
回帖

【科普】faster flu vaccine

只看楼主
页码直达：
直达末页

楼主

入门站友

1楼

这个帖子发布于11年零331天前，其中的信息可能已发生改变或有所发展。

Researchers Apply DNA Biology to Vaccination Technique
February 1, 2006 — Spraying viral genes directly through the skin is a new technique that turns infinitesimal amounts of DNA into an effective vaccine. If approved for use in humans, the new procedure could save lives in case of a flu pandemic, by skipping the current, time-consuming production of vaccines in chicken eggs.
LONDON--A new flu vaccine could save lives and protect us from a deadly outbreak. But can the United States handle a widespread flu epidemic? Most experts would agree -- not with the way we currently mass-produce the vaccine. It currently takes at least six months to a year to make flu vaccines, but that's soon to change.
We all know the signs; but what if a new, more-powerful, more-deadly strain of the flu emerges?
John Beadle, a researcher from the Infectious Disease and Oncology department at PowderMed, Ltd. in London, says, "The traditional way of making vaccines has a number of significant drawbacks."
The biggest drawback is the amount of time it takes to make, which is too long. This 1950's-style vaccine process using chicken eggs takes too long, putting lives at risk if an outbreak occurs. Now, a new vaccine based on flu virus DNA could be a faster way to fight the flu.
"DNA vaccines can be manufactured very rapidly, and they can be manufactured in large amounts," Dr. Beadle says.
Infectious disease researchers extract just a few genes from the DNA of the flu virus to make a vaccine. Then, microscopic particles are coated with the vaccine and shot into the body at super-fast speeds using this new, needle-free device. "It's because the DNA gets into the cells of the skin that it produces such a strong immune response," Dr. Beadle says.
A better response is important for older Americans, like 77-year old Claire Mobley. "Having had it once, I don't want to get it again."
This new, high technology could be the solution to an old problem -- producing a vaccine in half the time of traditional methods. Dr. Beadle says, "That means that a lot more lives can be saved within that period if we have a pandemic."
The new DNA vaccine and new administering device for influenza is not yet FDA approved. Human clinical trials are planned for this year to test it against the bird flu, but any mass-produced product is still several years away. A flu outbreak or worse -- a pandemic -- could speed up the FDA approval process and bring the vaccine closer to use.
BACKGROUND: Researchers have been working on a DNA-based vaccine for the flu for several years. While not yet ready for widespread use, if there were a global outbreak of the potentially deadly virus, such a vaccine could be fast-tracked into use. The Center for Disease Control estimates that more than 200,000 people in the U.S. are hospitalized each year as a result of the flu, and more than 30,000 die from it. Globally, the flu kills close to half a million people every year.
HOW VACCINES WORK: There are three basic strains of the flu virus: A, B and C. A is the most common strain, and the most severe. The flu vaccine works by triggering the body's immune system response. The body recognizes the vaccine as a foreign invader and produces antibodies to it. However, flu strains differ from year to year; that's why there is a different vaccine each year.
Currently, flu vaccines are made by incubating the three strains of the flu virus expected to strike in a given year are injected into millions of chicken eggs to multiply before being extracted and packaged. It is a labor-intensive and time-consuming technique that is much the same as when it was first invented in the 18th century.
WHAT ARE DNA VACCINES?: DNA vaccines are a form of gene therapy in which just a few genes are extracted from the virus and injected into people. Unlike the standard process, which takes up to six months, DNA-based vaccines could be ready in less than three months. The downside is they have never been tested in full-blown clinical trials.
WHAT IS THE FLU: The flu is caused by the influenza virus, which targets the respiratory tract by binding to the surface of cells. Then the virus releases its genetic information (RNA) into the cell's nucleus to replicate itself. When the cell dies, those copies are released into the body, infecting other cells. Flu symptoms are unpleasant, but not life-threatening by themselves. However, the flu weakens the immune system, making the body vulnerable to more serious infections, such as pneumonia.

邀请讨论

搜索

2009-03-06 07:35 浏览 : 701 回复 : 2

投票
收藏
打赏
引用
分享
- 微信扫一扫
- 新浪微博
- 丁香客
- 复制网址
举报
- 广告宣传推广
- 政治敏感、违法虚假信息
- 恶意灌水、重复发帖
- 违规侵权、站友争执
- 附件异常、链接失效
- 其他

• 论卫生高级职称下放单位自主评审的利弊

深海巨鲸

常驻站友

2楼

本人已认领该文编译，48小时后若未提交译文，请其他战友自由认领。

2009-03-06 11:45

投票
收藏
打赏
引用
分享
- 微信扫一扫
- 新浪微博
- 丁香客
- 复制网址
举报
- 广告宣传推广
- 政治敏感、违法虚假信息
- 恶意灌水、重复发帖
- 违规侵权、站友争执
- 附件异常、链接失效
- 其他

• 为什么有的医院患者少，工作轻松，但医生收入很高

深海巨鲸

常驻站友

3楼

研究人员将DNA生物学应用到疫苗接种技术中

2006年2月1日——通过喷涂病毒基因直接通过皮肤，将极少量的脱氧核糖核酸（DNA）变成有效的疫苗是一项崭新的技术。如果该项技术获得批准应用于人类，就能够省去当前从鸡蛋生产疫苗的耗时过程，在流感广泛流行时挽救生命。
伦敦——一种新的流感疫苗可以拯救生命，保护我们的生命免受致命性的突发疫情。但是，如果美国爆发大规模的流感疫情，能处理得了吗？大多数专家的意见是肯定的，不过并不是采用我们目前所使用的批量生产疫苗的方法。用目前方法生产出流感疫苗至少需要六个月到一年，不过这种情况马上就要发生变化了。
我们都知道的疫情发生前的征兆，然后再制作相应的疫苗去治疗；但是，如果一种新的，更强大，更致命的流感病毒出现呢？
任职于伦敦PowderMed有限公司传染病和肿瘤部的研究员约翰•比德尔声称：“传统的疫苗制造方法有诸多严重缺陷。”
其中最严重的缺陷就是制作耗时过长。目前使用的这种20世纪50年代的疫苗制作方法耗时过长，如果有新的疫情突然爆发，那将会使人们生命置于危险境地。现在，基于流感病毒DNA的一种新疫苗能够更快速地抵抗流感。
比德尔博士称：“这种 DNA疫苗可以迅速制造并大量生产。”
传染病研究人员仅需从流感病毒的DNA中，提取出少量几个基因用来制成疫苗。然后，将疫苗涂布在微粒（显微镜级）上，并将微粒用上述新的，无需用针注射的喷雾法以极快的速度喷射入人体。“该方法的原理是使病毒DNA快速进入皮肤细胞而使人体产生强烈的免疫反映。”比德尔博士解释道。
对于美国老年人来说，一次良好的免疫接种反应效果是很重要的，就像77岁的克莱尔•莫布里所说：“这种免疫接种反应对我来说一次就够了，我不想再经受第二次。”
这种新的高科技生产疫苗方法解决了困扰人们很久的一个难题，即缩短了生产疫苗的时间。新方法只需传统方法的一半时间。比德尔博士介绍说：“这意味着，一旦某个时间发生了一场全国行大规模的疫情，这种新方法就能快速生产疫苗，使更多的生命及时得到挽救。”
这种新的DNA疫苗和治疗流感的方法尚未获得美国食品药品监督管理局的批准。今年，计划进行人体临床实验，测试其对禽流感病毒的效果，但距使用该方法大规模生产产品仍有好几年的时间。一场流感，或者更糟，一场全国性流感的爆发，或许可以加快FDA批准进程，使新疫苗更快得到使用。
背景知识：研究人员致力于研究使用流感病毒的DNA作为疫苗已有好几年时间了。虽然还没有准备好普及应用，但一旦有一种潜在的致命性病毒全球性爆发，那么这种疫苗就可以快速投入使用。据疾病预防控制中心估计，每年有超过200, 000美国人因流感住院，并有超过30, 000人因此丧命。在全球范围内，每年流感造成的死亡人数有近50万人。
疫苗的作用原理：现有三种基本的流感病毒品系，分别为：A、B和C。A类病毒是最常见，也是最严重的一种。流感疫苗的工作原理是引发人体免疫系统的反应。当人们身体将疫苗识别为外来侵入物时，就会产生抗体抵抗它。但是，流感病毒株系年年都不同；这就是每年都有不同疫苗的原因。
目前，流感疫苗是通过将预计某年会出现的三种流感病毒株注射进数百万的鸡蛋中培育增殖得到的，然后再从鸡蛋中提出并进行包装。这是一项早在18世纪就被发明的耗时的劳动力密集型技术。
什么是DNA疫苗？：DNA疫苗是一种基因疗法，该方法只需提取病毒中的少量基因注射入人体。与现有方法的不同的是，标准的生产方法需要花费6个月时间，而DNA疫苗只需用不到三个月的时间。DNA疫苗的缺点是尚未对其进行完整的临床试验。
什么是流行性感冒：流感是由流感病毒引起的，流感病毒通过结合在呼吸道细胞的表面而靶定于呼吸道上。然后，将其的遗传信息——核糖核酸（RNA）释放进细胞的细胞核进行自我复制。当正常细胞死亡后，这些病毒的复制体就释放到了人体内，感染其他的细胞。流感的症状是会使人觉得不舒服，但就其本身而言是不会危及生命的。然而，流感会削弱人的免疫系统，使身体容易受如肺炎等的更严重传染疾病的攻击。

2009-03-08 21:40

投票
收藏
打赏
引用
分享
- 微信扫一扫
- 新浪微博
- 丁香客
- 复制网址
举报
- 广告宣传推广
- 政治敏感、违法虚假信息
- 恶意灌水、重复发帖
- 违规侵权、站友争执
- 附件异常、链接失效
- 其他

• 论卫生高级职称下放单位自主评审的利弊

科技动态

【科普】faster flu vaccine

提示

丁香园旗下网站

关于丁香园

官方链接

科技动态

分享到：

微信扫一扫

【科普】faster flu vaccine

微信扫一扫

微信扫一扫

微信扫一扫

提示

丁香园旗下网站

关于丁香园

官方链接