Gene pharming ; Molecular farming ; Pharming Introduction Biopharming is the production and use of transgenic plants and animals genetically engineered to produce pharmaceutical substances for use in humans or animals. It often involves the insertion of gene constructs derived from humans. Biopharming exists on a spectrum of activity and is not clearly demarcated from its nearest neighbors. For example, genetically modified yeast, bacteria, and animal cell cultures have for some time been used to produce pharmaceutical substances in enclosed bioreactor systems, but are generally not included in the definition of biopharming. On the other hand, plant cell cultures, a newer development but also involving enclosed bioreactors, are typically included together with whole-plant methods in plant biopharming.
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History[ edit ] The first recombinant plant-derived protein PDP was human serum albumin , initially produced in in transgenic tobacco and potato plants. While the United States Department of Agriculture has approved planting of pharma crops in every state, most testing has taken place in Hawaii, Nebraska, Iowa, and Wisconsin.
Proof of concept has been established for the production of many therapeutic proteins , including antibodies , blood products , cytokines , growth factors , hormones , recombinant enzymes and human and veterinary vaccines.
This raised a furor and set the pharming field back, dramatically. A compromise was reached, but Ventria withdrew its permit to plant in Missouri due to unrelated circumstances. The industry has slowly recovered, by focusing on pharming in simple plants grown in bioreactors and on growing GM crops in greenhouses. In Dow AgroSciences received USDA approval to market a vaccine for poultry against Newcastle disease , produced in plant cell culture — the first plant-produced vaccine approved in the U.
Blood, egg white, seminal plasma , and urine are other theoretically possible systems, but all have drawbacks. Blood, for instance, as of cannot store high levels of stable recombinant proteins, and biologically active proteins in blood may alter the health of the animals.
Hamsters and rabbits have also been used in preliminary studies because of their faster breeding. One approach to this technology is the creation of a transgenic mammal that can produce the biopharmaceutical in its milk or blood or urine.
Once an animal is produced, typically using the pronuclear microinjection method, it becomes efficacious to use cloning technology to create additional offspring that carry the favorable modified genome. Marketing permission was granted by the European Medicines Agency in August The patentability of such biopharmaceuticals and their process of manufacture is uncertain. Probably, the biopharmaceuticals themselves so made are unpatentable, assuming that they are chemically identical to the preexisting drugs that they imitate.
Several 19th century United States Supreme Court decisions hold that a previously known natural product manufactured by artificial means cannot be patented.
This issue has not yet been decided in the courts. In plants[ edit ] Plant-made pharmaceuticals PMPs , also referred to as pharming, is a sub-sector of the biotechnology industry that involves the process of genetically engineering plants so that they can produce certain types of therapeutically important proteins and associated molecules such as peptides and secondary metabolites.
The proteins and molecules can then be harvested and used to produce pharmaceuticals. Tobacco has been a highly popular choice of organism for the expression of transgenes, as it is easily transformed, produces abundant tissues, and survives well in vitro and in greenhouses. However, human error could still result in pharm crops entering the food supply. Using a minor crop such as safflower or tobacco, avoids the greater political pressures and risk to the food supply involved with using staple crops such as beans or rice.
Expression of proteins in plant cell or hairy root cultures also minimizes risk of gene transfer, but at a higher cost of production.
This characteristic makes them an appealing target for the production of edible vaccines , as viral coat proteins stored in grains do not require cold storage the way many vaccines currently do. Maintaining a temperature controlled supply chain of vaccines is often difficult when delivering vaccines to developing countries.
The protein of interest is often expressed under the control of the cauliflower mosaic virus 35S promoter CaMV35S , a powerful constitutive promoter for driving expression in plants. This is done in order to improve yields, simplify purification, or so that the protein folds properly. Researchers in Japan transformed rice with an antisense SPK gene, which disrupts starch accumulation in rice seeds, so that products would accumulate in a watery sap that is easier to purify.
These frugal organisms can be cultivated in bioreactors as opposed to being grown in fields , secrete the transformed proteins into the growth medium and, thus, substantially reduce the burden of protein purification in preparing recombinant proteins for medical use.
There are differences in the regulation of GM crops — including those used for pharming — between countries, with some of the most marked differences occurring between the USA and Europe. Regulation varies in a given country depending on the intended use of the products of the genetic engineering. For example, a crop not intended for food use is generally not reviewed by authorities responsible for food safety.
There are also specific controversies around pharming. Advantages[ edit ] Plants do not carry pathogens that might be dangerous to human health. Additionally, on the level of pharmacologically active proteins , there are no proteins in plants that are similar to human proteins. On the other hand, plants are still sufficiently closely related to animals and humans that they are able to correctly process and configure both animal and human proteins.
Their seeds and fruits also provide sterile packaging containers for the valuable therapeutics and guarantee a certain storage life. Expanding the existing microbial systems, although feasible for some therapeutic products, is not a satisfactory option on several grounds. For these reasons, science has been exploring other options for producing proteins of therapeutic value.
The World Health Organization estimates that nearly 3 million people die each year from vaccine preventable disease, mostly in Africa. Diseases such as measles and hepatitis lead to deaths in countries where the people cannot afford the high costs of vaccines, but pharm crops could help solve this problem.
In the case of genetically modified GM foods, concerns focus on the safety of the food for human consumption. In response, it has been argued that the genes that enhance a crop in some way, such as drought resistance or pesticide resistance , are not believed to affect the food itself.
Other GM foods in development, such as fruits designed to ripen faster or grow larger, are believed not to affect humans any differently from non-GM varieties. Considerable attention is focused, therefore, on the restraint and caution necessary to protect both consumer health and environmental biodiversity. They worry that once production begins, the altered plants might find their way into the food supply or cross-pollinate with conventional, non-GM crops. Activists also are concerned about the power of business.
Was in process of launching trypsin product in  when later that year its field test crops contaminated conventional crops. Stine,  who owns one of the biggest soybeans genetics companies in the US.