Scientists are working on eye transplants for vision loss. Who will sign up?
Awash in a fluid finely calibrated to keep it alive, a human eye rests inside a transparent cubic device. This ECaBox, or Eyes in a Care Box, is a one-of-a-kind system built by scientists at Barcelona’s Centre for Genomic Regulation (CRG). Their goal is to preserve human eyes for transplantation and related research.
In recent years, scientists have learned to transplant delicate organs such as the liver, lungs or pancreas, but eyes are another story. Even when preserved at the average transplant temperature of 4 Centigrade, they last for 48 hours max. That's one explanation for why transplanting the whole eye isn’t possible—only the cornea, the dome-shaped, outer layer of the eye, can withstand the procedure. The retina, the layer at the back of the eyeball that turns light into electrical signals, which the brain converts into images, is extremely difficult to transplant because it's packed with nerve tissue and blood vessels.
These challenges also make it tough to research transplantation. “This greatly limits their use for experiments, particularly when it comes to the effectiveness of new drugs and treatments,” said Maria Pia Cosma, a biologist at Barcelona’s Centre for Genomic Regulation (CRG), whose team is working on the ECaBox.
Eye transplants are desperately needed, but they're nowhere in sight. About 12.7 million people worldwide need a corneal transplant, which means that only one in 70 people who require them, get them. The gaps are international. Eye banks in the United Kingdom are around 20 percent below the level needed to supply hospitals, while Indian eye banks, which need at least 250,000 corneas per year, collect only around 45 to 50 thousand donor corneas (and of those 60 to 70 percent are successfully transplanted).
As for retinas, it's impossible currently to put one into the eye of another person. Artificial devices can be implanted to restore the sight of patients suffering from severe retinal diseases, but the number of people around the world with such “bionic eyes” is less than 600, while in America alone 11 million people have some type of retinal disease leading to severe vision loss. Add to this an increasingly aging population, commonly facing various vision impairments, and you have a recipe for heavy burdens on individuals, the economy and society. In the U.S. alone, the total annual economic impact of vision problems was $51.4 billion in 2017.
Even if you try growing tissues in the petri dish route into organoids mimicking the function of the human eye, you will not get the physiological complexity of the structure and metabolism of the real thing, according to Cosma. She is a member of a scientific consortium that includes researchers from major institutions from Spain, the U.K., Portugal, Italy and Israel. The consortium has received about $3.8 million from the European Union to pursue innovative eye research. Her team’s goal is to give hope to at least 2.2 billion people across the world afflicted with a vision impairment and 33 million who go through life with avoidable blindness.
Their method? Resuscitating cadaveric eyes for at least a month.
If we succeed, it will be the first intact human model of the eye capable of exploring and analyzing regenerative processes ex vivo. -- Maria Pia Cosma.
“We proposed to resuscitate eyes, that is to restore the global physiology and function of human explanted tissues,” Cosma said, referring to living tissues extracted from the eye and placed in a medium for culture. Their ECaBox is an ex vivo biological system, in which eyes taken from dead donors are placed in an artificial environment, designed to preserve the eye’s temperature and pH levels, deter blood clots, and remove the metabolic waste and toxins that would otherwise spell their demise.
Scientists work on resuscitating eyes in the lab of Maria Pia Cosma.
Courtesy of Maria Pia Cosma.
“One of the great challenges is the passage of the blood in the capillary branches of the eye, what we call long-term perfusion,” Cosma said. Capillaries are an intricate network of very thin blood vessels that transport blood, nutrients and oxygen to cells in the body’s organs and systems. To maintain the garland-shaped structure of this network, sufficient amounts of oxygen and nutrients must be provided through the eye circulation and microcirculation. “Our ambition is to combine perfusion of the vessels with artificial blood," along with using a synthetic form of vitreous, or the gel-like fluid that lets in light and supports the the eye's round shape, Cosma said.
The scientists use this novel setup with the eye submersed in its medium to keep the organ viable, so they can test retinal function. “If we succeed, we will ensure full functionality of a human organ ex vivo. It will be the first intact human model of the eye capable of exploring and analyzing regenerative processes ex vivo,” Cosma added.
A rapidly developing field of regenerative medicine aims to stimulate the body's natural healing processes and restore or replace damaged tissues and organs. But for people with retinal diseases, regenerative medicine progress has been painfully slow. “Experiments on rodents show progress, but the risks for humans are unacceptable,” Cosma said.
The ECaBox could boost progress with regenerative medicine for people with retinal diseases, which has been painfully slow because human experiments involving their eyes are too risky. “We will test emerging treatments while reducing animal research, and greatly accelerate the discovery and preclinical research phase of new possible treatments for vision loss at significantly reduced costs,” Cosma explained. Much less time and money would be wasted during the drug discovery process. Their work may even make it possible to transplant the entire eyeball for those who need it.
“It is a very exciting project,” said Sanjay Sharma, a professor of ophthalmology and epidemiology at Queen's University, in Kingston, Canada. “The ability to explore and monitor regenerative interventions will increasingly be of importance as we develop therapies that can regenerate ocular tissues, including the retina.”
Seemingly, there's no sacred religious text or a holy book prohibiting the practice of eye donation.
But is the world ready for eye transplants? “People are a bit weird or very emotional about donating their eyes as compared to other organs,” Cosma said. And much can be said about the problem of eye donor shortage. Concerns include disfigurement and healthcare professionals’ fear that the conversation about eye donation will upset the departed person’s relatives because of cultural or religious considerations. As just one example, Sharma noted the paucity of eye donations in his home country, Canada.
Yet, experts like Sharma stress the importance of these donations for both the recipients and their family members. “It allows them some psychological benefit in a very difficult time,” he said. So why are global eye banks suffering? Is it because the eyes are the windows to the soul?
Seemingly, there's no sacred religious text or a holy book prohibiting the practice of eye donation. In fact, most major religions of the world permit and support organ transplantation and donation, and by extension eye donation, because they unequivocally see it as an “act of neighborly love and charity.” In Hinduism, the concept of eye donation aligns with the Hindu principle of daan or selfless giving, where individuals donate their organs or body after death to benefit others and contribute to society. In Islam, eye donation is a form of sadaqah jariyah, a perpetual charity, as it can continue to benefit others even after the donor's death.
Meanwhile, Buddhist masters teach that donating an organ gives another person the chance to live longer and practice dharma, the universal law and order, more meaningfully; they also dismiss misunderstandings of the type “if you donate an eye, you’ll be born without an eye in the next birth.” And Christian teachings emphasize the values of love, compassion, and selflessness, all compatible with organ donation, eye donation notwithstanding; besides, those that will have a house in heaven, will get a whole new body without imperfections and limitations.
The explanation for people’s resistance may lie in what Deepak Sarma, a professor of Indian religions and philosophy at Case Western Reserve University in Cleveland, calls “street interpretation” of religious or spiritual dogmas. Consider the mechanism of karma, which is about the causal relation between previous and current actions. “Maybe some Hindus believe there is karma in the eyes and, if the eye gets transplanted into another person, they will have to have that karmic card from now on,” Sarma said. “Even if there is peculiar karma due to an untimely death–which might be interpreted by some as bad karma–then you have the karma of the recipient, which is tremendously good karma, because they have access to these body parts, a tremendous gift,” Sarma said. The overall accumulation is that of good karma: “It’s a beautiful kind of balance,” Sarma said.
For the Jews, Christians, and Muslims who believe in the physical resurrection of the body that will be made new in an afterlife, the already existing body is sacred since it will be the basis of a new refashioned body in an afterlife.---Omar Sultan Haque.
With that said, Sarma believes it is a fallacy to personify or anthropomorphize the eye, which doesn’t have a soul, and stresses that the karma attaches itself to the soul and not the body parts. But for scholars like Omar Sultan Haque—a psychiatrist and social scientist at Harvard Medical School, investigating questions across global health, anthropology, social psychology, and bioethics—the hierarchy of sacredness of body parts is entrenched in human psychology. You cannot equate the pinky toe with the face, he explained.
“The eyes are the window to the soul,” Haque said. “People have a hierarchy of body parts that are considered more sacred or essential to the self or soul, such as the eyes, face, and brain.” In his view, the techno-utopian transhumanist communities (especially those in Silicon Valley) have reduced the totality of a person to a mere material object, a “wet robot” that knows no sacredness or hierarchy of human body parts. “But for the Jews, Christians, and Muslims who believe in the physical resurrection of the body that will be made new in an afterlife, the [already existing] body is sacred since it will be the basis of a new refashioned body in an afterlife,” Haque said. “You cannot treat the body like any old material artifact, or old chair or ragged cloth, just because materialistic, secular ideologies want so,” he continued.
For Cosma and her peers, however, the very definition of what is alive or not is a bit semantic. “As soon as we die, the electrophysiological activity in the eye stops,” she said. “The goal of the project is to restore this activity as soon as possible before the highly complex tissue of the eye starts degrading.” Cosma’s group doesn’t yet know when they will be able to keep the eyes alive and well in the ECaBox, but the consensus is that the sooner the better. Hopefully, the taboos and fears around the eye donations will dissipate around the same time.
The Top 8 Things to Know About Anti-Aging Research Right Now
Dr. Michael West has a storied legacy in the world of aging research. Twenty years ago, the company he started, Geron, hit upon a major breakthrough when his scientists isolated the active component for the gene that confers immortality to cells, called telomerase.
In the twenty years since, a new field has emerged: the science of extending the human "healthspan."
He was in the lab when scientists for the first time artificially turned on the gene in some skin cells donated by Dr. Leonard Hayflick, the man who had discovered back in 1965 that human cells age over time. Sure enough, with Geron's intervention, Hayflick's skin cells became immortal in the dish, and the landmark paper was published in Science in 1998.
In the twenty years since, a new field has emerged: the science of extending the human "healthspan" – the length of time people can live free of diseases related to aging. A substantial amount of preclinical and some clinical research is now underway, backed by heavy investments from some of the world's largest companies.
Today, Dr. West is the CEO of AgeX Therapeutics, a biotech company that is developing novel therapeutics to target human aging and age-related degenerative diseases using pluripotent stem cells. Dr. West recently shared some key insights with Editor-in-Chief Kira Peikoff about what's happening in this exciting space.
1) Pluripotent stem cells have opened the door for the first time in human history to manufacturing young cells and young tissue of any kind.
These are the body's master cells: They are self-replicating, and they can potentially give rise to any cell or tissue the body needs to repair itself. This year marks the 20th anniversary since their isolation for the first time in a lab.
"People in biotech say that the time from lab to discovery in products is about 20 years," West says. "But the good news is we're at that 20-year mark now, so you're seeing an explosive growth of applications. We can now make all cell types of the human body in a scalable manner."
2) Early human development could hold the key to unlocking the mystery of aging.
West believes that two things occur when the body forms in utero: telomerase, the immortalizing gene, gets turned off very early in development in the body cells like skin, liver, and nerves. Additionally, he thinks that a second genetic switch gets turned off that holds the potential for regeneration after injury.
"These insights open the door to intervention by the transfer of telomerase into the cells of the body."
"Very early when the body is first forming, if you cut the skin, it will not respond by scarring, but will regenerate scarlessly," he says. "But that potential gets turned off once the body is formed, about 8 weeks after fertilization. Then, you accumulate damage over a lifetime. Not only do cells have a finite capacity to replicate, but you have tissue damage."
However, there are animals in nature whose telomerase is never turned off, or whose regenerative ability is never turned off. The flatworm, for example, can regenerate its own head if it gets cut off, and it also shows no detectable aging. Lobsters are believed to be similar. (That's not to say it can't get caught and eaten for dinner.)
"These insights open the door to intervention by the transfer of telomerase into the cells of the body, or understanding how regeneration gets turned off, and then turning it back on," West says. "That's well within the power of modern medical research to understand."
3) Companies are investing tremendous resources into the anti-aging gold rush.
Devising interventions is the mission of AgeX, a subsidiary of BioTime, as well as a number of other companies.
"We're seeing a mad rush," West says. There's Google's Calico, which recently announced, with AbbVie Inc., another $1 billion into research for age-related diseases, on top of the previous $1.5 billion investment.
Other notable players include Unity Biotechnology, Samumed, Human Longevity Inc., RestorBio, Rejuvenate Bio,and Juvenescence (which is also an investor in AgeX).
"These are products in development by our company and others that the baby boomers can reasonably anticipate being available within their lifetimes."
4) The majority of clinical applications are still years away.
"What we've learned about turning back on this regenerative state, called induced tissue regeneration, is that the majority of the clinical implications are years away and will require years of clinical trials before potential FDA approval and marketing to the public," West says. "But we have found some potential near-term applications that we think may have a much faster track to commercialization. As you can imagine, we are all over those."
BioTime, Inc., AgeX's parent, has a regenerative medicine product in clinical trials for age-related macular degeneration, the leading cause of blindness in an aging population. While not yet approved by the FDA, BioTime has reported continued progress in the clinical development of the product now in Phase II trials.
Dr. Michael West, CEO of AgeX
Citi recently issued a major report, Disruptive Innovations VI, that included "Anti-Aging Medicines" as the number two innovation for investors to keep an eye on, and predicted that the first anti-aging therapies could receive regulatory approval by 2023.
5) Few, if any, medical interventions are available today that are proven to markedly slow aging - yet. But the Baby Boomers are not necessarily out of luck.
Buyer beware of any claims in the marketplace that a given skin cream or stem cell product will extend your life. More than likely, they won't.
"There are a lot of people trying to cash in on the aging baby boom population," West warns.
"When you hear claims of stem cell products that you can get now, it's important to understand that they are likely not based on pluripotent stem cell technology. Also, they are usually not products approved by the FDA, having gone through clinical trials to demonstrate safety and efficacy."
However, an array of young pluripotent stem cell-derived therapies are on a development track for future approvals.
One example is another program at AgeX: the manufacture of brown fat cells; these cells burn calories rather than store them. They burn circulating fat like triglycerides and sugar in the blood and generate heat.
"You lose brown fat in aging, and animal models suggest that if you restore that tissue, you can restore a metabolic balance to be more like what you had when you were young," says West. "When I was 18, I could drink milkshakes all day long and not gain an ounce. But at 50 or 60, most of us would rapidly put on weight. Why? We believe that one important factor is that with age, you lose this brown fat tissue. The loss throws your metabolism off balance. So the solution is conceptually simple, we plan to make young brown fat cells for transplantation to reset the balance, potentially to treat Type II diabetes or even obesity.
"These are products in development by our company and others that the baby boomers can reasonably anticipate being available within their lifetimes."
6) There is an ethical debate about how far to apply this new science.
Some people are speculating about whether genetic engineering might one day be used to program longer lifespans into humans at the earliest stages of development. (Note: it is against the law across the Western world to edit human embryos intended for reproduction, although just last week, Chinese scientists used CRISPR to repair a disease-causing mutation in viable human embryos.)
West sounds a cautionary note about such interventions meant to lengthen life. "For people who think not just about the science, but the ethics, safety is a major concern. It's entirely possible to genetically engineer babies, but when you make such modifications, it's an experiment, not just in human cells in a dish, but in a human being. I have a great reticence to put any human at risk unless it's a case where the person is suffering with a life-threatening disease, and the potential therapy is their last best hope."
"I have no doubt, zero doubt, that in the foreseeable future, we'll hear of a person who has lived to about 150."
7) The biggest challenge of intervening in human aging is cultural denial.
"The prospect of intervening in a profound way in human aging is still not seen as credible by the vast majority of thoughtful people around the world," West laments.
"Aging is a universal phenomenon, it's mankind's greatest enemy, but as a species we've adapted to the realities of finite lifespans and death. We have a whole infrastructure of belief systems around this, and many people see it as inevitable."
8) The lifespan for healthy children born today could surpass anything humanity has ever seen.
"It is at least 150 years of age," West predicts. "I have no doubt, zero doubt, that in the foreseeable future, we'll hear of a person who has lived to about 150. We know now it's possible. I've never said that publicly before, but I am comfortable now with the prediction. And, of course, if some people now living could live to 150 years of age, we have the prospect of them living to see even more powerful therapies. So, the question now is, what kind of a world are we going to make for future generations?"
[Editor's Note: Check out our latest video, which was inspired by Dr. West's exclusive prediction to leapsmag.]
Kira Peikoff was the editor-in-chief of Leaps.org from 2017 to 2021. As a journalist, her work has appeared in The New York Times, Newsweek, Nautilus, Popular Mechanics, The New York Academy of Sciences, and other outlets. She is also the author of four suspense novels that explore controversial issues arising from scientific innovation: Living Proof, No Time to Die, Die Again Tomorrow, and Mother Knows Best. Peikoff holds a B.A. in Journalism from New York University and an M.S. in Bioethics from Columbia University. She lives in New Jersey with her husband and two young sons. Follow her on Twitter @KiraPeikoff.
[Editor's Note: To learn more about this exciting field, check out: The Top 8 Things to Know About Anti-Aging Research Right Now.]
Kira Peikoff was the editor-in-chief of Leaps.org from 2017 to 2021. As a journalist, her work has appeared in The New York Times, Newsweek, Nautilus, Popular Mechanics, The New York Academy of Sciences, and other outlets. She is also the author of four suspense novels that explore controversial issues arising from scientific innovation: Living Proof, No Time to Die, Die Again Tomorrow, and Mother Knows Best. Peikoff holds a B.A. in Journalism from New York University and an M.S. in Bioethics from Columbia University. She lives in New Jersey with her husband and two young sons. Follow her on Twitter @KiraPeikoff.