A New Gene Engineering Method Could Allow Us to Grow Organs for Transplants

A Chemical Approach

Making an organism’s genome — its entire genetic structure, from scratch — is already possible, but so far it’s only been successful in tiny bacterial genomes and in a portion of a yeast genome. Several researchers are working on synthesizing the entire human genome, but our current methods are limited because of their dependence on enzymes.

Now, a team of researchers from the University of Southampton in the U.K., working with colleagues from the University of Oxford and DNA synthesis firm ATDBio (based in Southampton and Oxford), propose a new method that could surpass these limitations.

In a study published in the journal Nature Chemistry, the researchers showcased a purely chemical technique for gene assembly. It uses an efficient and rapid-acting chemical reaction called click chemistry that puts together multiple modified DNA fragments into a gene — a process called click DNA ligation.

Image Credit: US Department of Energy

“Our approach is a significant breakthrough in gene synthesis,” University of Southampton Chemical Biology Professor and Lead Researcher Ali Tavassoli said in a press release. “Not only have we demonstrated assembly of a gene using click-chemistry, we have also shown that the resulting strand of DNA is fully functional in bacteria, despite the scars formed by joining fragments.”

Human Genome Synthesis

Although plans to synthesize the human genome from scratch have been received with mixed feelings and ethical considerations, its appeal comes from the possibilities it has to offer. According to GP-write, an international effort working on engineering large genomes, applications of DNA synthesis include growing transplantable human organs from scratch, engineering viral immunity and cancer resistance, and even allowing for more efficient and cost-effective drug development and testing.

Ethical quandaries notwithstanding, synthetic DNA is promising. With it, we could be looking at better ways to treat DNA-based diseases, or edit them out altogether — ultimately, extending human life or even potentially creating it from scratch, so to speak. “Genome synthesis will play an increasingly important role in scientific research,” Tavassoli explained. He believes their approach will make it more possible.

A shortcoming of current methods involves the extensive use of enzymes, which can’t be incorporated into certain sites that control the expression (i.e., the switching “on” or “off”) of genes. This so-called epigenetic information can be crucial to better understand biological processes, e.g., cancer, which couldn’t be cured too soon.

“The synthesis of chemically modified genes, which we have achieved by a radical new approach, will become ever more important as the effects of epigenetically modified DNA on gene expression become clear,” study co-author Tom Brown said in the press release.

Furthermore, the chemical method could also greatly accelerate the synthesis of larger DNA strands, producing larger quantities of a single gene. “We believe our purely chemical approach has the potential to significantly accelerate efforts in this vitally important area, and ultimately lead to a better understanding of biological systems,” Tavassoli added.

The post A New Gene Engineering Method Could Allow Us to Grow Organs for Transplants appeared first on Futurism.

Futurism

Transplants of Genetically Modified Pig Organs for Humans Could Happen Within Two Years

Xenotransplantation

This year, novel organ transplant procedures have been getting a fair amount of attention. While some may seem rather bizarre — like that human head transplant currently in the works — others could be the beginning of a new era in organ transplantation. Chinese researchers have been working on using genetically modified pig organs for human transplantation, and they expect it to be available in the next two years.

Because they closely resemble human organs in terms of size and metabolism, pig organs are considered to be the best animal organs for human transplants — a procedure known as xenotransplantation. Studies involving pig organ transplants have shown considerable benefits, most notably a baboon that received a pig’s heart was able to survive for three years.

In order to confirm these effects, researchers from more than 10 institutes in China have asked permission from the government to conduct human clinical trials use pig organs for transplants. These trials are part of a a national xenotransplantation project funded by the Chinese central government.

Piggy Organ Bank

China seems to be leading the way in this field, producing more genetically modified pigs than any other country. For pig organ transplants to work, modifying pigs by removing certain genes are necessary to prevent the human immune system from rejecting the donated organsThe South China Morning Post (SCMP) reports that cloning farms in China produce a total of 1,000 cloned pigs a year, according to one researcher.

That’s potentially a huge pig organ bank, assuming the government manages to approve clinical trials soon. For Zhao Zijian, director of the Metabolic Disease Research Centre at Nanjing Medical University in Jiangsu, the government seems to be taking too long.

An Exponential Timeline of Organ Transplants
Click to View Full Infographic

“We have patients dying from organ failure and their desperate relatives pleading for them to have the chance to live,” Zhao, who’s also a senior scientist at a xenotransplantation lab, told the SCMP. “But when we turn to the authorities in charge of approving the clinical trials, all we get is silence. We understand it must be very hard for the government to make a decision, but it’s time we got an answer.”

Pig organs could speed up the process of getting transplants. In China, for instance, over 300,000 patients require organ transplants, but only less than 10,000 organs are donated each year. Moving forward, initiative when it comes to coming up with the necessary regulations are needed. “Someone has to take the first step – whether it’s the US Food and Drug Administration or the China Food and Drug Administration,” Zhao said.

The post Transplants of Genetically Modified Pig Organs for Humans Could Happen Within Two Years appeared first on Futurism.

Futurism

A New Technique Could Revolutionize Organ Transplants

Deep Freeze

A group of scientists from the University of Warwick has taken inspiration from nature for a new research project that could greatly improve the process of human organ transplantation.

An Exponential Timeline of Organ Transplants
Click to View Full Infographic

The researchers have developed a new synthetic antifreeze that mimics the properties of natural antifreeze proteins (AFPs). These proteins are produced naturally by extremophile species in cold environments, which need to be able to moderate the formation and spread of ice in order to survive.

The Warwick team’s synthetic antifreeze is iron-based, and they attribute its ability to slow the growth of ice crystals to the separation of the iron complex into regions with either water-loving or water-hating characteristics, imitating the composition of APFs found in nature.

Heart of Ice

This synthetic antifreeze could be useful for a wide range of applications, from making airplane wings less susceptible to the cold to helping produce smoother ice cream. However, it could have a major impact on something far more significant than dessert: organ transplants.

After organs are removed from a donor, they have to be iced in order to prevent them from dying off before they reach their recipient. This process is problematic, as organs typically only last for four hours before being rendered unusable. Sixty percent of hearts and lungs donated for transplants are discarded each year due in part to this short shelf life.

If organs were frozen, and not simply put in cold storage, they could last longer, but under normal circumstances, organs simply can’t survive the freezing process — cells are liable to shrivel up or even collapse entirely, the matrices that connect cells together might be torn apart, and blood vessels can disintegrate entirely.

Ice crystals are the cause of all of these major problems. If the Warwick researchers’ synthetic antifreeze can thwart the growth of these crystals, it could make it possible for surgeons to freeze organs without the associated negative effects. This would make transplants safer and add a lot more flexibility to the process in terms of timing and transport.

Most significantly, this ability to freeze organs could dramatically decrease the number of donations that are wasted as a result of their short timeframe for use. Data from the U.K. suggests that if half of the wasted organs were actually used, transplant waiting lists could be eliminated within just a couple of years.

This project hasn’t yet moved to trials using human organs, so real-world use is still far off, but the research has the potential to give people waiting for transplants a much better shot at getting the organ donation they need.

The post A New Technique Could Revolutionize Organ Transplants appeared first on Futurism.

Futurism

Nanoparticles fool your body into allowing organ transplants

Organ transplants are frequently life-saving, but they remain a gamble when your body can reject the new organ well after the initial surgery. Yale researchers have discovered a clever solution to this: prevent your body from noticing the organ unti…
Engadget RSS Feed

Artificial skin transplants could be used to treat diabetes

Skin grafts made using CRISPR gene editing are preventing mice from developing diabetes, and scientists claim they could prove beneficial for humans too. In a proof-of-concept study, researchers at the University of Chicago edited stem cells from new…
Engadget RSS Feed