by Catherine Haug, September 14, 2014
We know GMOs as a genetically engineered ‘food’ – for example, bT corn which is genetically engineered to produce the toxin normally produced by the bT bacteria. This substance is toxic to pests that eat the corn. Unfortunately, if you eat a food product made from bT corn, it includes the DNA that can produce that toxin, so that when ingested, it can potentially produce the toxin in your body too.
But that type of GMO product is just the tip of the technology iceberg. Bio-tech companies are rapidly expanding and modifying the technique for many other applications. For example, forcing a tobacco plant to produce a new type of antibiotic that helps the body fight off infection by the ebola virus. At first blush, this seems like a good, novel idea. But Science still doesn’t know the long-term effects of the application of this technology, just as it doesn’t know (or doesn’t admit) the long-term effects of GMO ‘foods.’
How does this new antibody technique work?
Agroinfiltration: a GE (genetically engineered) technology
This is the technique used to produce the antibiotic against Ebola by the drug company ZMapp. While a similar technology can be used to force animals (rats, etc.) to produce the drug, the Ebola drug is produced by a tobacco plant. NOTE: this is not the same variety of tobacco used to make cigarettes, but rather a close cousin. Tobacco plants are especially useful for this type of research and production because they were one of the first crops to be GMO, so a lot is known about them and how they work. Furthermore, tobacco plants are natural chemical factories, producing nicotine which is toxic to tobacco pests.
How does it work? Before I get to that, lets do a quick review of some terms:
- DNA: the chemical genetic makeup that provides the code to produce proteins as sequences of specific amino acids. Generally these proteins are important for the life of the organism, such as enzymes that help digest food. But when genetically engineered DNA is used, proteins with a specific alternate function or role are produced – such as an enzyme that produces a synthetic toxin or drug.
- GMO (Genetically Modified Organism): an organism whose natural DNA has been modified by inserting a select part of the DNA of another species or a synthetic genetic sequence.
- Bacteria: single-cell organism in the plant kingdom; bacteria can be beneficial such as the lacto-bacteria in our gut, or harmful such as pathogenic or disease-causing bacteria.
- Virus: an organism, generally smaller than a cell and missing some aspects of a cell, that is generally disease-causing, such as the Ebola virus.
The following is based on a Take Part blog post by By
They start with a bacteria that naturally resides in soil, and has the ability to insert a portion of its own DNA into the DNA of another species to do harm – this is a natural version of GE technology. Then they genetically modify the DNA of this bacteria to produce a different protein that, in the case of the Ebola antibiotic, helps to strengthen the immune system of the person infected with the Ebola virus, so that the body will be able to fight off the Ebola invader.
In its simplest form, the process goes like this: Scientists force a plant-infecting bacteria, genetically modified to include a gene for the desired protein, into a [tobacco] leaf by pressing a syringe (no needle) against a tiny nick in the plant’s skin. The bacteria, a natural soil pathogen, can then wriggle its way into the surrounding cells and hijack their production systems, basically bossing them into churning out the medicine.
Or a more efficient method can be used to infect the tobacco plant and force it to do the scientists bidding throughout the plant (rather than in just a small part of the plant where the syringe was used):
First, plants are flipped upside down and dipped into vats of [the desired GMO] bacteria-infused liquid. Then the plants are shoved into a vacuum, which sucks all the air out of the space between cells…[allowing] ‘the bacteria [to be] sucked into the leaf and allowed to infiltrate the cells,’ making a plant-size medicine factory.
Or more traditional GMO techniques can be used to produce a GMO tobacco plant designed to produce a drug much like normal tobacco produces nicotine.
The end result, no matter which method is used, is the GE production of a substance that produces the desired drug for the desired effect. In the case of the Ebola drug, it enhances the body’s own immune system to fight off the invading virus.
Other applications of this technology
from the Take Part article (1): Besides Ebola, tobacco is also being used:
- As a factory for antibodies against West Nile virus, which kills hundreds of people in the United States every year. Researchers at Arizona State University used antibodies grown in N. benthamiana (as well as in lettuce) to save 90 percent of mice that had been given a lethal dose of the virus.
- Wycoff’s company is using tobacco to develop antibody treatments for dental cavities and the common cold. It is also looking beyond typical therapeutic antibodies, to see what other kinds of biological drugs tobacco can produce.
- Of Planet Biotechnology’s upcoming products, the farthest along is a treatment for anthrax that combines two types of protein in one biological medicine. It works as a decoy, luring anthrax toxin away from human cells and neutralizing it.
- Another of the company’s prospective disease treatments is for Middle Eastern Respiratory Syndrome, or MERS, a deadly virus that everyone was freaking out about before Ebola came back to freak us out more. This Planet Biotechnology treatment is a decoy, similar to the anthrax treatment. It’s been effective at saving human cells from the virus in a dish, and the company is now applying for cash to start testing in live animals.
- Tobacco agroinfiltration can also be used for preventive measures, including traditional vaccines. For example a tobacco-produced flu vaccine made by Medicago, a biotech company owned jointly by Mitsubishi and Phillip Morris. Current production of the flu vaccine relies on incubating chicken eggs for six months; agroinfiltration clocks in at around a week.
The big question; what do you think?
Do you think this is a good and safe method for producing drugs and vaccines? Does the supposed benefit outweigh the potential long-term harm of using the GE technology?
You decide. If you wish to comment on this question, please send an email to Cat (see ESP Contact), and I’ll add it as a comment to the post. Please indicate whether you want me to use your first name, first and last names, your initial(s), or a fake name.
References
- Take Part blog post by By : takepart.com/article/2014/09/10/ebola-drug-zmapp-from-tobacco