This is post no. 1 under the main topic.
| 06-27-2010, 04:41 PM
(This post was last modified: 07-04-2010, 10:42 PM by Charles.)
A vaccine is a special preparation of biological elements that enhances immune system in the body of the host against a particular disease. Usually a vaccine contains a disease causing agent which induces immune system of the body by producing antibodies against those agents in the body. Those disease causing agents remain in the killed or nonfunctional attenuated form in the vaccine. So they do not create any disease in the host but are very much effective to create specific immune system in the host cell. At first the term vaccine was used by Edward Jenner in 1796 from the Latin name of cowpox causing agent variolæ vaccine. Vaccines can be of two types, some vaccines are developed to prevent the further infection by the causal agent who is called prophylactic and some vaccines are therapeutic such as vaccines to prevent cancer which still remains under investigation.
Gene’s expression of microbial cells is from pathogens which encode surface antigens. Neutralizing antibodies are induced in the host of the pathogen by those antigens. This technique is the most elementary application of genetic engineering in vaccine development. This technique is developed in the preparation of hepatitis B vaccine successfully. HBV vaccine is now used widely all around the world.
Preparation of vaccine is not so easy now. It needs to know some fundamental matters such as virulence determination, antigenic variation, response against viral antigens etc. In the primitive stage of vaccine application, antigen from the causing agents are directly injected into the host body. It was very harmful for human body. Now we are living in the time of genetic engineering where safe and secured life is ensured to everybody as much as possible. So vaccines are now prepared in the simplest and safe way by genetic engineering.
Like all the products of biotechnology and genetic engineering, vaccines have created a wide business environment all around the world. Vaccine preparation and manufacturing are now a leading areas for the young scientists and scientific companies. They are not only committed to give us the vaccines of seasonal influenza but also promised to give us vaccines of crucial diseases such as cancer or AIDS as early as possible. This worldwide leading area has also involved to create bioterrorism. So vaccination is a confusing matter for the people of third world countries. Till now vaccines business is a high risk business considering their low price and short lifetime. Competition amongst the vaccines exported companies, low efficiency of the vaccine manufacturers and commercial thinking greater than humanity are responsible for the bad affects on this sensitive business.
Businessmen are now trying to improve and manipulate vaccines in a better way so they introduce new innovation in the field of vaccines. Vaccines are now developed in combination with dendrite cell to work efficiently in the white blood cells for stimulating immune system. Recombinant vectors are used as vaccine in the host body’s cell receptor peptide vaccines are now under research. Bacterial proteins are developed in bacterial virulence mechanism by complement inhibition reaction. So vaccines manipulated by the genetic engineering can be the most essential tools for human body in the upcoming times.
This is post no. 2 under the main topic.
| 06-30-2010, 11:24 PM
The simplest application of the modern genetic manipulation methods to vaccine development is the expression in microbial cells of genes from pathogens that encode surface antigens capable of inducing neutralizing antibodies in the host of the pathogen involved. This procedure has been exploited successfully for development of a vaccine against hepatitis B virus (HBV) that is now widely used.
This is post no. 3 under the main topic.
| 06-30-2010, 11:39 PM
Additionally, BCG vaccine used to protect against Mycobacterium tuberculosis. Vaccines are effective in preventing disease not only in individuals, but also in communities often known as "herd immunity."
This is post no. 4 under the main topic.
| 10-04-2012, 03:20 AM
(This post was last modified: 10-04-2012, 03:31 AM by Administrator.)
We all know that “Prevention is better than cure” and this meaning is all abbreviated in term vaccine itself! Humans are top animal when it comes to the course of evolution. This is only because it has advantage over other animals with respect to memory, brain capacity. With the use of brain, today human being is ruling the world leaving behind all other animals. This memory is not only what we remember consciously but also what we remember sub-consciously somewhere beneath our biological system. This is the biological system which takes care of our life while defending with deadly pathogens. The unique system of immunity! When pathogens are encountered, they are remembered by our immune system which is known as memory of immunity or plasma cells. This concept is being employed to protect possible future diseases by knowingly introducing attenuated pathogens i.e. Vaccines!
Today tolerogenic vaccine could be the new era in the field of vaccination which stops the inflammation component of heart disease.
It is being observed by research that memory cells get developed against inflammation in any location of circulatory (heart) system. The second encounter increase the attack intensity and cause heart disease or plague formation in arteries. With the development of tolerogenic vaccines, it is greatly possible to reduce the autoimmunity attack and thus helps in prevention of plague in arteries. This concept had developed curiosity in scientists to develop vaccines for heart diseases as well as other diseases related to auto-immune responses like inflammation! Yes prevention is better than cure but it is also being said that man is as old as his arteries and if we take care of it well in advance with tool like tolerogenic vaccine, it will be better than prevention !
This is post no. 5 under the main topic.
| 04-26-2014, 10:16 PM
The advancement in the application of genetic engineering concerning vaccination lies in the way it is performed. We are moving from the regular vaccines to edible ones. The basic principle behind them is that the proteins from a certain disease causing pathogen are present in the fruit we eat, for example, helping our immunity to improve. This can solve a lot of problems concerning the vaccination, especially since millions of people are dying because they do not have access to traditional vaccines.
Why edible vaccines?
The idea was started by Charles Arntzen at Texas A&M University with the intention to make vaccination more available to the whole world. Around 20% of world’s infants still do not receive six essential vaccines – against polio, measles, tetanus, tuberculosis, diphtheria and pertussis. With edible vaccines, this problem could be solved since they would be cheaper to produce and would not require refrigeration. Moreover, they could be grown locally and they could be regenerated indefinitely so the amount of vaccines would not be limited. This would also solve the problems of transportation to places. Another benefit of edible vaccines is that they are consumed orally instead of being injected, which would also solve the problem of potential infections that might arise.
Current research also suggests that using edible vaccines might help with the autoimmune diseases like multiple sclerosis, type I diabetes and rheumatoid arthritis.
The making of edible vaccine
One of the ways to produce edible vaccines is by using bacterium Abrobacterium tumefaciens which will carry our genes for antigen and ultimately deliver them into the plant cells.
- We must first have the bacteria which contain the plasmid with our gene of interest and antibiotic-resistance gene.
- The next step is to take the leaf of the plant, cut it and expose it to the bacteria (by putting it in bacterial suspension). This will allow the bacteria to deliver the genes into the plant cells.
- Then we should remove the cells that have not received the genes of interest by exposing the whole leaf to an antibiotic.
- After only transformed cells have survived, we should wait in order for the callus tissue to form (undifferentiated plant cells).
- The last thing to do is to cultivate plantlets and transform them to the soil where they will grow and produce our edible vaccine.
This is post no. 6 under the main topic.
| 03-18-2015, 03:05 AM
The modern genetic manipulation methods to vaccine development is the expression in microbial cells of genes from pathogens that encode surface antigens capable of inducing neutralizing antibodies in the host of the pathogen involved.
This is post no. 7 under the main topic.
| 06-08-2015, 11:55 PM
(This post was last modified: 06-10-2015, 12:25 AM by dbaezner.)
Hi. Newbie question. What stops a vaccine from triggering the very illness it's supposed to prevent? It's my understanding that viruses like Ebola aren't really alive, but are able to trick host cells into replicating the virus's DNA. How then do you "kill" such a virus so that it's dead form triggers the creation of antibodies but not the illness you're trying to prevent?
This is post no. 8 under the main topic.
| 06-10-2015, 08:32 PM
It's all about the 'particle' being used for vaccine development. For vaccine development, 'virulent' portions of the genes/proteins are knocked off. Only those proteins/genes are utilized as 'antigens' that may act as the fingerprints of the pathogen, but not the arsenal.
Hope it clears your doubt to some extent.
This is post no. 9 under the main topic.
| 06-10-2015, 10:44 PM
Thanks again, Sunil.
I appreciate your time.