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本帖最后由 StephenW 于 2011-1-19 20:50 编辑
回复 凋零尘埃 的帖子
在网上我找不到任何提及GY-DNA的资料,所以也不知道它是什么类型的DNA疫苗.
以下是从Wikipedia有关DNA疫苗的简要说明.
DNA疫苗不同于其他药物，它通常是服用一个很短的时间。也不会造成耐药.
http://en.wikipedia.org/wiki/DNA_vaccination
DNA vaccination is a technique for protecting an organism against disease by injecting it with genetically engineered DNA to produce an immunological response. Nucleic acid vaccines are still experimental, and have been applied to a number of viral, bacterial and parasitic models of disease, as well as to several tumour models. DNA vaccines have a number of advantages over conventional vaccines, including the ability to induce a wider range of immune response types.
Vaccines are among the greatest achievements of modern medicine – in industrial nations, they have eliminated naturally-occurring cases of smallpox, and nearly eliminated polio, while other diseases, such as typhus, rotavirus, hepatitis A and B and others are well controlled.[1] Conventional vaccines, however, only cover a small number of diseases, and infections that lack effective vaccines kill millions of people every year, with AIDS, hepatitis C and malaria being particularly common.
First generation vaccines are whole-organism vaccines – either live and weakened, or killed forms.[2] Live, attenuated vaccines, such as smallpox and polio vaccines, are able to induce killer T-cell (TC or CTL) responses, helper T-cell (TH) responses and antibody immunity. However, there is a small risk that attenuated forms of a pathogen can revert to a dangerous form, and may still be able to cause disease in immunocompromised people (such as those with AIDS). While killed vaccines do not have this risk, they cannot generate specific killer T cell responses, and may not work at all for some diseases.[2] In order to minimise these risks, so-called second generation vaccines were developed. These are subunit vaccines, consisting of defined protein antigens (such as tetanus or diphtheria toxoid) or recombinant protein components (such as the hepatitis B surface antigen). These, too, are able to generate TH and antibody responses, but not killer T cell responses.
DNA vaccines are third generation vaccines, and are made up of a small, circular piece of bacterial DNA (called a plasmid) that has been genetically engineered to produce one or two specific proteins (antigens) from a pathogen. The vaccine DNA is injected into the cells of the body, where the "inner machinery" of the host cells "reads" the DNA and converts it into pathogenic proteins. Because these proteins are recognised as foreign, when they are processed by the host cells and displayed on their surface, the immune system is alerted, which then triggers a range of immune responses.[1][2] These DNA vaccines developed from “failed” gene therapy experiments. The first demonstration of a plasmid-induced immune response was when mice inoculated with a plasmid expressing human growth hormone elicited antibodies instead of altering growth.[3]
DNA疫苗是保护被注射到基因工程的DNA产生的免疫反应是对疾病的生物技术。核酸疫苗仍处于试验阶段，并已应用到病毒，细菌和寄生虫疾病的模型，以及一些肿瘤型号。 DNA疫苗的优点比传统的疫苗，包括能够诱导免疫反应类型的更广泛范围内的数字。
疫苗在现代医学的最大成就是 - 在工业国家，他们已经消除自然发生的天花病例，几乎消除了小儿麻痹症，而其他疾病，如伤寒，轮状病毒，甲肝和乙肝等是很好的控制[。 1]传统的疫苗，但是，只包括少数的疾病和感染，缺乏有效的疫苗，每百万人死亡的一年，艾滋病，丙型肝炎和疟疾是特别常见。
第一代疫苗是全生物疫苗 - 。要么生活和削弱，或杀死形式[2]减毒活疫苗，如天花，脊髓灰质炎疫苗，能诱导杀伤T细胞（TC或CTL）的反应，辅助性T细胞（TH）的免疫反应和抗体。然而，有一个小风险的病原体减毒形式可以恢复到一个危险的形式，可能仍然能够引起人们的免疫功能低下疾病（如与艾滋病患者）。虽然杀死疫苗没有这个风险，他们不能产生特定的杀手T细胞的反应，并可能不适用于某些。[2]为了最大限度地减少这些风险，所谓的第二代疫苗研制的疾病的。这是亚单位疫苗，确定蛋白抗原（如破伤风或白喉类毒素）或重组蛋白成分（如乙肝表面抗原）组成。这些，也同样能产生TH和抗体反应，但不杀伤性T细胞的反应。
DNA疫苗是第三代疫苗，是由一个小的，圆片细菌的DNA（称为质粒）基因工程已经从病原体产生一个或两个（抗原）的特定蛋白质了。该疫苗的DNA注入身体，那里的“内在机制”的宿主细胞的“读取”DNA和蛋白质转化为它的致病细胞。由于这些蛋白质是外国，当他们处理由宿主细胞的表面上显示的认可，免疫系统通知，然后触发免疫反应的范围。[1] [2]这些DNA来自“研制的疫苗失败“基因治疗实验。
一个质粒诱导的免疫反应的第一示威, 当老鼠接种一质粒表达人生长激素, 它引起的抗体，而不是改变经济增长[3]
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发表于 2011-1-19 16:14
