The healing power of eggs

The idea of using a biological system to produce products for human use is not new. Since civilization began, humans have harnessed bacteria, yeast and more to produce alcoholic drinks, fermented foods and, later on, things like silk and insulin.

Modern-day scientists are taking biological systems engineering to the next level. Indeed, it’s now a university degree program offered at major institutions around the world. Experts are applying fundamental principles of engineering to living systems to produce everything from drugs to organic computers.

For some time, bacteria, yeast and some types of mammalian cells have been used to produce a group of pharmaceuticals called pharmaceutical proteins. Using an egg to produce these protein drug treatments is a relatively new idea, but one that makes a lot of sense. Eggs provide a sterile, closed environment and the capability of large-scale production at relatively low cost, all allowing mass manufacture of a given compound that would otherwise be unfeasible.

It turns out that eggs are suitable to produce a particular cell-signalling protein called interferon beta (some biological systems are better suited than others to produce particular proteins). Interferon beta can not only disarm viruses like the one that causes hepatitis, but can also control some cancers as well as auto-immune diseases like multiple sclerosis. In short, it’s in hot demand.

Enter researchers at Japan’s National Institute of Advanced Industrial Science and Technology, who have genetically engineered hens to produce eggs with large amounts of interferon beta in the whites. Their first step is to edit genes found in chicken sperm. They then use these modified sperm to fertilize eggs. The resulting male chicks are then crossbred, with interferon beta produced in the eggs of the hen offspring. The research was jointly conducted with scientists from Japan’s National Agriculture and Food Research Organization and a Japanese company called Cosmo Bio.

If commercialized, this method will be a great improvement over the traditional way that interferon beta is produced. Presently, it’s a very technologically intensive process involving bacteria or mouse ovarian cells that produce only small volumes. However, when the Cosmo Bio process will be commercialized and the cost to produce protein this way is still unknown.

We do know that the company plans to begin selling interferon beta in the new manner as a research reagent in 2018. Company spokesperson Mika Kitahara says the price of producing this reagent is “about one-tenth the cost compared with [the] former procedure.” We also know that developing a process to produce interferon beta on a commercial scale likely will require increasing the amount of interferon beta that can be produced per egg. On that front, researchers will have to meet requirements for standard regulatory testing.

It wouldn’t be the first time that the U.S. Food and Drug Administration (FDA) has approved a drug produced through the gene editing of chickens. In 2015, it permitted such a treatment for a rare and very serious disease known as lysosomal acid lipase deficiency, also called Wolman disease. The FDA stated in a press release at the time that the deadly disease “results in a build-up of fats within the cells of various tissues that can lead to liver and cardiovascular disease and other complications”.

Celiac treatment
Scientists at the University of Alberta have developed a new treatment for celiac disease using an antibody derived from egg yolks. According to the Canadian Celiac Association (CCA), about one in 133 people in Canada are affected by the condition, where damage to the absorptive surface of the small intestine is caused by gluten.

The association notes on its website that a gluten-free diet “can be very challenging to follow, as it is complicated and expensive. In addition, there are concerns about the nutritional adequacy of gluten-free products, as they can be high in fat and sugar, and often low in fiber, iron and B vitamins.”

That is why U of A associate professor of pharmaceutical sciences Hoon Sunwoo developed the treatment in partnership with his colleague Jeong Sim, who is retired from the university. Sunwoo could not be reached for comment, but he’s noted in the past that it’s difficult to completely avoid gluten because it can be present but unlisted in food and drugs.

Sunwoo and Sim discovered that antibodies in egg yolk binds with a component of gluten called gliadin, preventing its absorption. Sunwoo states on his university web page that “these antibodies are effective for gastrointestinal drug delivery and efficiently neutralize immunogenic gluten.” The treatment was patented in the U.S. in 2012 and a human clinical trial (phase I) was successfully conducted in 2014. CCA executive director Melissa Secord notes further studies are on hold pending Health Canada approvals.

Biomedical micro-circuitry
Scientists are also using egg whites to develop a biodegradable circuit device. This innovation can power various small-scale medical processes inside the body, like delivering drugs to specific body sites and detecting disease early. This biological resister (called a memrister) is the brainchild of scientists Jack (Jikui) Luo at Bolton University in the U.K., Xiaozhi Wang at Zhejiang University in China and their colleagues.

The resister consists of electrodes made of magnesium and tungsten attached to an ultra-thin film made from vigorously whipped diluted egg whites (albumen). The resistor’s performance is similar to conventional resistors of the same type. It dissolves in a few hours in water in the lab, with total breakdown achieved in a few days.

Luo notes that research of albumen-based devices is at an early stage. “For [body] implant applications, not just memister devices but also other electronic devices used to process information are needed,” he says. “All of them are being researched by many people around the world, and it will take tens of years for these types of devices to be used for implants. We are working on a number of devices, but none of them could be used soon.”