Not sure how to quite start this, maybe with a little background again. For some time I had been involved in the alternative lifestyle. I had never really put much thought into GMO technology because it seemed so out of my knowledgesphere. I had heard the phrase Frankenfoods, I had vaguely heard of a company called Monsanto. But on the whole not much. I was told that I should avoid GM foods. It never really struck me as something that important. Now since I started my nursing education I have been taking care a lot of people with diabetes and have to use insulin. Again it wasn’t something I had thought much about until someone pointed out to me that human insulin is made using GM technology. Since throwing my weight behind the pro-gmo camp I have found it amazing that people are so against this technology; even people who work in healthcare who either just want to remain ignorant or just are ignorant of it’s value. I find this technology amazing! Not only is going to save lives, it already has.
For the record, I am not a biologist, but I’d like to think that I’ve got a rudimentary knowledge of it. Which is why I tend to check up with sites like Sense About Science, Genetic Literacy Project and Skeptical Raptor. I do not reference in any kind of organized way but I do provide as many links as possible where I feel it is needed... and sometimes where it isn’t needed.
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| Left: Child on starvation diet Right: Same child after getting insulin |
Diabetes mellitus (DM) type 1 and 2 are diseases that affect a persons ability to regulate their blood glucose levels. Both diseases are characterized by chronic high blood sugar. If left unregulated, high blood sugar can lead to acute diabetic ketoacidosis and death with long term complications of kidney failure, heart disease and blindness. DM type 1 and 2 are frightening illnesses, that depending on how you think of it, we have only fairly recently been able to get control of. The key word being control because we still have not found a cure for either, only management strategies.
Historically, DM is not a new disease There have been references to both types of DM in ancient Egyptian manuscripts and the name diabetes was coined by Ancient Greeks. In India they had already divided DM into two types; if you were “lucky” enough to receive a diagnosis you might survive for a further 1.4 years, but more often than not you would die within months if not weeks. The standard treatment at the time was starvation, which remained the standard treatment for type 1 DM until the discovery of insulin.
Insulin was discovered in the 1920's by Dr. Frederick Banting, who experimented on hundreds of dogs. It had been previously known that DM had something to do with the pancreas, but the association with the disease was still undiscovered. Dr. Banting's dog experiment established that dogs without their pancreas would develop diabetes; their blood sugars would shoot up and they’d get hungry and thirsty. All of that subsided when they were injected with ground up pancreas. Dr. Banting's would go onto discover that it was a substance called insulin that is created by the beta cells that are located in the Islets of Langerhans in the pancreas that regulates the blood sugar. After extensive experimentation, it was decided to try injecting insulin into a person, a 14 year old boy who was at deaths door before being given the first insulin injection. He went on to live live for a further 13 years.
The history of insulin is quite fascinating. It was the first protein that was completely sequenced in the 50’s. Up until the 1980’s, we were using bovine and porcine insulin; meaning that we were essentially harvesting insulin from the slaughtered leftovers of cows and pigs. While insulin from animal sources saved a lot of lives, there were major drawbacks with allergic reactions, not to mention that bovine and porcine insulin are not human insulin and there was not such thing as "control". Something had to be done to find a supply of insulin that was reliable and continuous. Researchers in the 1960's had been able to synthesize some insulin, but not enough to satisfy demand. That all changed in the 70’s when a company called Genentech started working with City of Hope Research Institute to combine human insulin gene into a bacteria in order to create insulin. Following extensive testing and refining, it was released for the general public in the 1980’s. I’ll try and explain the process of GE human insulin as simply as possible.
To make human insulin the pharmaceutical companies use a Recombinant DNA Technology, they insert insulin gene into a bacteria called E.Coli, though some manufacturers use yeast. As stated before insulin is a protein, it is composed of 51 amino acids, that are separated into A Chain with 21 amino acids and B chain with 30. A and B chain are synthesized separately. The bacteria with their new gene are allowed to ferment and thus multiply. After sufficient amount of time they are then taken out of their fermenting tanks and broken up, with the insulin protein chains extracted. The two strains are then combined with a disulfide bond. Then when all of that is done, the whole mixture is purified even further so all we end up with is a big batch of insulin. Then thereafter they add other ingredients to the mix in order to prevent bacterial contamination, to create a neutral base and to create intermediate to long-acting insulin.
There will be steps that I have missed, but in a nutshell that is how it is done. So yeah insulin. GMO. And since its discovery it has saved millions of lives that otherwise would not have been possible. Currently, there is some exciting work where insulin is harvested from Safflowers. Which would be cheaper and possibly easier to produce, along with that it could be better suited for inhalable insulin. Again, this is GMO technology at its best.
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| Spanish Flu killed 50 - 100 million worldwide |
I have already waxed lyrically about the importance of the flu vaccine for health care workers. The flu is a very serious disease at any age, but it is at its most deadly for children under five and the elderly, and of course those who suffer from immunodeficiencies due to assorted reasons. As a healthcare worker I see it as my duty to get the flu vaccine every season. The flu vaccine, unfortunately, is probably the least effective vaccine we have got at the moment. Depending on the season it’s efficacy can vary from 30% - 70%. The way we make the influenza vaccine at the moment is by using eggs. Lots and lots of eggs. And usually it takes between 1 - 2 eggs per dose of vaccine; it’s very laborious and, well, inefficient. There are couple of problems that we face with the any flu vaccine; to make a more effective and universal vaccine it would take around 12-15 years of research to develop and create with a cost somewhere between $500 million to $1 billion. This puts off nearly all of the pharmaceutical companies. Another problem with flu vaccines made from eggs is that people with egg allergies can suffer allergic reactions, hence there are now two different ways of creating a flu vaccine in the works, and one that is still being researched.
The first one is called FluBlok, created by Protein Sciences, which uses a recombinant technology and insect cell cultures to create the vaccines. This is done by injecting a baculovirus into the insect cell culture, which in turns creates a protein that most influenza viruses have called hemagglutunin. This methods uses no other fragments of the flu virus, it contains no traces of adjuvants or antibiotics, and most importantly, no egg. Unfortunately, so far it has been found to be 44% effective.
The second one is called Flucelvax, made by Novartis. Again this is made with cell culture, but this time of mammalian origin. Other than the origins of the cell culture, Flucelvax is made using the same technology as FluBlok . Remarkably, Flucevlax was found to be more effective than FluBlok, 77% effective in fact.
Both rely on Recombinant DNA Technology. It is a technology that cuts up DNA molecules and splices the fragments together in. In other words it is the process taking a DNA fragment from somewhere else and fuse it with another DNA fragment. For example the insulin gene that has been spliced into an E.Coli bacteria.
The third flu vaccine is personally the one that excites me the most. This flu vaccine is made from genetically modified tobacco plants. Finally tobacco plants will be used for something other than to puff into our lungs. The business Medicago is leading the way in this front; for each plant, there is the potential of up to 50 doses of a flu vaccine. The exact details I don’t know and even if I did, I wouldn't be allowed to say. In essence:
“Although the exact process is proprietary, Medicago starts with tobacco plants grown in greenhouses. After about five weeks, the plants are suspended in a solution made from a human-safe bacteria found in soil. That solution in effect tells the tobacco plant to produce large quantities of an influenza viral protein. Once the plants take up that solution, they incubate for about five days.” [Source]
Unfortunately this is still in testing stages, but it would be a great cost-saver as it’s the cheapest way they have found to make a flu vaccine. At least until they find a universal flu vaccine. Medicago has been concentrating on using plants in order to create their vaccines, because it’s a comparatively inexpensive process and produces higher yields. Additionally, a flu vaccine can be made ready within 3 weeks from identifying a seasonal and/or pandemic strain.
These systems all have the advantage that they are not dependent on egg supply and more time can be dedicated towards calculating what flu strains will be most commonly in circulation.
Other medication that uses Recombinant Technology is rhGH. Which is short for recombinant Human Growth Hormone, under the brand name Humatrope. Human Growth Hormone (HGH) is necessary to stimulate cell production, growth and regeneration. It is created in the pituitary gland located in the brain. If there is lack of HGH in children, than the effects are diminished growth, obesity, lack of sexual development and disrupted mental development. There is also the danger of hypoglycaemic episodes. Again, this is where Genentech came in; they inserted the DNA code for HGH into plasmids that were then in turn introduced into our superhero bacteria, E. coli. Prior to this we had to harvest human growth hormones from human cadavers (much like insulin was harvested from slaughtered cows and pigs), and in order to gain at least a years supply you would need up to 50 pituitary glands.
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| The last Tsar family, Alexis the youngest had haemophilia. |
Then there’s haemophilia. Haemophilia is a genetic condition where blood clotting factors are impaired, causing a person to bleed profusely even with a minor wound. This is usually a genetic disorder where there is a lack of Factor VIII. The most famous example of this is the last Tsar family where Alexis, the youngest son, badly suffered from the condition. Currently, we rely on blood donations in order to treat this, which is all well and good, but we continually run into the problem of lack of donations. Spurred on by worries surrounding the lack of consistent screening of blood, and with the potential of contaminations and antibody formation to donated blood, a group of scientists in 1986 developed a way to create Factor IX. This was done by splicing Factor IX gene into plasmids, that were then inserted into hamster ovary cells along with plasmids that were treated with a gene that was coded for resistance against methotrexate.
These are just a few examples of GE technology in medicine. There are already over 110 medications on the market that are made using biotechnology with more being researched everyday and more than 350 million people feeling the benefits because of it. For example we also have antithrombin III, used to prevent blood clotting during surgery, that we collect from the milk of transgenic goats. There has been some research done regarding a vaccine against Alzheimer's using tomatoes. Organ transplant might not have to rely on organ donors anymore, with research going into making tissue that could be used to make variety of human organs! This technology provides us with the best tools in order to combat diseases that at this moment have no cure. Not only that, with the current problem we are facing regarding antibiotic resistance, biotechnology is being used to fully explore alternatives. Thanks to this technology, we are developing even more cancer treatments, and while the cure might be some time off, at least we can give people more quality years of life. With this we technology we also can stop relying on animal derived products and go towards plant based manufacturing, instead of using CHO cells. It allows us to produce more convenient storage of raw materials at a lower cost and is arguably better for the environment.
Yet out there are people who are against biotechnology, mostly for what seems to be idealistic reasons rather than any actual factual reasons. Most people who are against GMO don’t seem to realize just how useful and prevalent it is, or in fact what it is. They don’t seem to understand that biotechnology has been in use ever since humankind picked up agriculture. Biotechnology in medicine has been used, successfully, for the last 30-odd years! They don’t seem to be able to reconcile that the GMO technology they oppose so much (especially in agriculture) is helping to keep people with diabetes and haemophilia alive and well. For me, personally, as someone who works in healthcare, I cannot wait to assist people with more effective treatments as they become available. I am meant to work as part of an evidence-based practice and people who are against this technology, for whatever reasons, are not following the evidence.
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