久久久精品欧美一区二区三区,国产欧美久久久精品影院,亚洲AV福利天堂一区二区三亚洲欧洲日韩国产AⅤ在线,亚洲成av人在线视,四虎国产精品永久地址99自拍三区一级国产片,亚洲男人的天堂久久无在线观看免费黄视频,亚洲一级特黄大片在线播放,国产成人精品区在线观看

Vaccine
Home > Application > Vaccine > Inactivated/ attenuated virus vaccine

Inactivated/ attenuated virus vaccine

Whole-virus vaccines use a weakened (attenuated) or inactivated form of the pathogen that causes disease to induce protective immunity against it. There are two types of whole virus vaccines. Live attenuated vaccines use a weakened form of the virus that can still grow and replicate, but not cause disease. Inactivated vaccines contain viruses whose genetic material has been damaged by heat, chemicals or radiation so they cannot infect cells and replicate, but can still induce an immune response.

 

Both are proven vaccination strategies that form the basis of many existing vaccines -- including the yellow fever and measles vaccine (live-attenuated vaccine) or the seasonal influenza and hepatitis A vaccine (inactivated vaccine). Vaccines that are attenuated from of bacteria also exist, such as the BCG vaccine for tuberculosis.

 

Advantages and disadvantages of live attenuated vaccines include: it is a well-established technology that induces a robust immune response involving both B and T cells; it is relatively simple to produce, but it is not suitable for people with compromised immune systems, and in rare cases may cause illness; and such products are usually relatively temperature sensitive, so careful storage is necessary.

 

Inactivated vaccines are also a mature technology and are suitable for people with compromised immune systems. Since they have no active ingredients, there is no risk of vaccine-induced disease; the production of this type of vaccines is relatively simple, and the products are relatively stable; however, booster immunization may be required .

 

Live attenuated vaccines are derived from viruses that have been weakened under laboratory conditions so that when injected they infect cells and replicate but cause no or very mild disease. However, they may not be suitable for people with compromised immune systems (such as those with HIV) and pregnant women, because even a weakened virus can cause illness in these people. Also, in rare cases, live attenuated vaccines can be reverted to a more pathogenic form, causing illness in the vaccinated individual or their contacts.

 

Because these vaccines are just weakened versions of natural pathogens, the immune system responds like any other cellular invader, mobilizing a range of defenses against it, including killer T cells (which recognize and destroy infected cells), helper T cells (which support antibody production) and antibody-producing B cells (which target pathogens lurking elsewhere in the body, such as the blood). This immune response persists until the virus is cleared from the body, which means memory cells have ample time to develop resistance to the virus. Because of this, live-attenuated vaccines can elicit an immune response almost as much as exposure to wild-type viruses without causing disease.

 

Inactivated virus vaccines also contain disease-causing viruses or parts of viruses, but their genetic material has been destroyed. For this reason, they are considered safer and more stable than live attenuated vaccines and can be given to people with compromised immune systems. Although their genetic material has been destroyed, inactivated viruses often contain many proteins that the immune system can respond to. But because they cannot infect cells, inactivated vaccines only stimulate an antibody-mediated response, and that response can be weaker and shorter-lived. To overcome this problem, inactivated vaccines are usually administered with an adjuvant and a booster immunization may be required.

 

Different viruses require slightly different production strategies, which means that each requires separate equipment and facilities. For example, the flu virus grows inside fertilized eggs -- which themselves must come from specialized sterile egg-laying facilities. The polio virus is grown in cell culture dishes that require different handling, while the bacteria-based vaccine is grown in large bioreactors. The growth of live pathogens also means that strict precautions must be taken to avoid viral escape.

 

Once large numbers of viruses or bacteria have been grown, they must be separated, purified, attenuated or inactivated, depending on the vaccine. Each of these steps requires specific equipment, reagents, and rigorous procedures to avoid and check for contamination, further increasing costs.


Related Products
Contact Us
  • Tel.: +86 021 6434 0155
  • E-Mail: marketing@duoningbio.com
  • Address: Building 30, No. 1525 Minqiang Road, Songjiang District, Shanghai
Message

Copyright ? Shanghai Duoning Biotechnology Co., Ltd. All Rights Reserved Sitemap | Technical Support: Reanod

WeChat
WeChat

Message-

Duoning Biotechnology

+86 021 6434 0155

丝袜美腿亚洲一区二区| 久久久久国产精品人妻AⅤ麻豆| 国产在线视频福利资源站| 在线看黄Ⅴ免费网站免费看| 高清国产天干天干天干| 性生生活大片又黄又| 无码国产精品一区二区免费模式| 人妻精品久久久久中文字幕一| 精品日本一区二区三区在线观看| 理论片国产在线播放免费| 国产伦精品一区二区三区妓女| 国产亚洲精品自在线观看| 亚洲精品无码永久在线观看| 成人黄色视频在线| 久久综合伊人99麻豆| 国产清纯白嫩初高生在线观看| 亚洲VA欧美VA天堂V国产综合| 亚洲AV无码国产一区二区三区| 色欲久久久天天天综合网精品| 国产成人精品在线播放| 少妇无码太爽了不卡在线观看| 国产精品福利区一区二区三区四区| 人妻精品久久久久中文字幕| 国产成人无码精品久久久露脸| 久久国产乱子伦精品免费女| 久久人人爽天天玩人人妻精品| 国产成人无码免费看片软件| 午夜鲁丝片AV无码免费| 亚洲国产综合在线观看不卡| 国产精午夜一区二区三区不卡久免費資訊| 亚洲爆乳成av人在线视菜奈实| 欧美亚洲综合在线一区| 少妇激情无码av一区二区| 天天天天躁天天爱天天碰2018| 中文字幕精品一区二区三区| 亚洲欧美中文日韩在线V日本| 国内精品久久久久免费网站| 老牛精品久久久久久中文| 无码国产色情18一20岁片A片| 九九精品亚洲一区二区三| 精品自拍视频在线观看|