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 > DNA Vaccine

DNA Vaccine

Nucleic acid-based diagnostic and therapeutic platforms are promising tools that are replacing protein-based platforms due to their unique properties, such as thermostability, resistance to denaturation, and simple storage. A good vaccine platform should be rapid, simple to develop, reproducible, thermostable, and manufacturable with reduced development costs and risks. The DNA platform addresses many of these challenges.


DNA vaccines are DNA vectors such as bacterial plasmids, minicircular DNA, or linear, covalently closed expression constructs that contain at least one eukaryotic expression cassette encoding the antigen of interest. An expression cassette typically consists of a eukaryotic promoter/enhancer, antigen gene, and poly(A) signal sequence, which are essential for antigen expression in eukaryotic cells such as muscle cells. DNA vaccines have shown convincing safety and immunogenicity in preclinical studies. Several DNA vaccines are currently approved for veterinary use in both large animals (such as horses) and small animals (such as chickens). India, based on the safety, immunogenicity and efficacy results of the ZyCoV-D Phase 3 trial, granted it emergency use authorization, which is also a milestone in the development of DNA vaccines. Clinical trials of DNA vaccines for West Nile virus (WNV), Ebola and Marburg viruses, and SARS-CoV-2 have shown that antibodies are produced in humans weeks after immunization. But there are also many cases of poor immunogenicity in clinical trials. Target antigens and optimization of construction, formulation, and delivery methods appear to be key factors in the immunogenicity of DNA vaccines.


In the past few years, many advances have been made in the field of DNA vaccines. Advances in DNA construction, delivery and administration routes, and the use of molecular adjuvants have enhanced the immunogenicity of DNA vaccines. DNA immunization promises to revolutionize the field of vaccines. DNA vaccines are less expensive to manufacture and store, making them ideal candidates for global vaccinations, even in low-income countries.


Plasmid DNA is produced by genetically modified bacteria, usually Escherichia coli (E. coli). Production of plasmid DNA following Good Manufacturing Practice (GMP) at preclinical and clinical scale requires careful development of optimal and economical commercial processes. Bacterial cells are grown under fermentative conditions, usually in a defined or minimal cell culture medium consisting of chemically defined substances such as glucose or glycerol as a carbon source, salts, vitamins, etc. After fermentation, bacterial cells are harvested by centrifugation or microfiltration. Cell lysis is then performed using chemical, physical or mechanical methods. Cell lysis produces a lysate containing cell debris, plasmid DNA, and soluble impurities. Clarification techniques such as tangential flow filtration are used to remove solids from lysates. Contaminants (e.g., host proteins, endotoxin, RNA, genomic DNA, linear and open circular forms of plasmid DNA). Purified plasmid DNA is formulated with excipients and adjuvants and filtered through sterile filters.


Minicircle DNA was generated by inducing intramolecular recombination of the parental plasmid in E.Coli. For example, the expression of recombinases, such as φC31 integrase, and restriction enzymes (REs), such as I-SceI, is induced by the arabinose-inducible gene expression system. Recombinases mediate site-specific recombination between their recognition sequences, resulting in two distinct circular DNA molecules (i) a minicircular DNA containing a eukaryotic expression cassette and (ii) a mini-plasmid (MP), MP can be specifically degraded by the induced RE. Minicircle DNA can then be extracted, purified, and formulated similarly to the method used for DNA plasmids.

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

国产精品无码午夜福利| 亚洲AV永久无码精品水牛影视| 国产一区二区三区无码视频| 男警察自己解下警裤自慰| 午夜神马福利电影不卡在线a | 午夜无码一区二区三区在线观看| 国产成人AV日韩色情| 日韩性爱视屏一区二区免费网| 啦啦啦在线观看视频免费观看| 久久婷婷五月综合国产尤物app| 精品国产成人a区在线观看| 一区二区三区精品视频在线观看| a亚洲Va欧美va国产综合| 中文综合无码一区二区三区| 超级97碰碰碰碰久久久久最新| 国产蜜桃一区二区三区在线观看 | 亚洲第一AAAAA片| 国产AⅤ精品一区二区三区| 伊人五月综合大香线蕉| 午夜自产精品一区二区三区演员| 色综合久久88色综合天天| 福利视频一区二区| 国产成人综合久久精品尤物| 无码久久综合久中文字幕| 色国产精品一区在线观看| 华人骚妇在线播放| 丰满人妻一区二区三区免费视频| 图片区小说区区亚洲五月| 91综合高清自在线看| 免费无码av一区二区三区| 天堂av无码av一区二区三区| 欧美一区二区手机在线观看视频| 精品久久人人爽人人玩人人妻| 亚洲成色www久久网站| 亚洲午夜福利在线网| 久久久久久中文字幕| 久久天天躁狠狠躁夜夜爽| 成全动漫视频在线观看免费播放| 亚洲色aⅴ性色在线观无码| 无码专区在线男人的天堂| 丰满人妻一区二区三区免费视频|