New Hope for Organ Transplantation: Life Without Anti-Rejection Drugs
Rob Waddell dreaded getting a kidney transplant. He suffers from a genetic condition called polycystic kidney disease that causes the uncontrolled growth of cysts that gradually choke off kidney function. The inherited defect has haunted his family for generations, killing his great grandmother, grandmother, and numerous cousins, aunts and uncles.
But he saw how difficult it was for his mother and sister, who also suffer from this condition, to live with the side effects of the drugs they needed to take to prevent organ rejection, which can cause diabetes, high blood pressure and cancer, and even kidney failure because of their toxicity. Many of his relatives followed the same course, says Waddell: "They were all on dialysis, then a transplant and ended up usually dying from cancers caused by the medications."
When the Louisville native and father of four hit 40, his kidneys barely functioned and the only alternative was either a transplant or the slow death of dialysis. But in 2009, when Waddell heard about an experimental procedure that could eliminate the need for taking antirejection drugs, he jumped at the chance to be their first patient. Devised by scientists at the University of Louisville and Northwestern University, the innovative approach entails mixing stem cells from the live kidney donor with that of the recipient to create a hybrid immune system, known as a chimera, that would trick the immune system and prevent it from attacking the implanted kidney.
The procedure itself was done at Northwestern Memorial Hospital in Chicago, using a live kidney donated by a neighbor of Waddell's, who camped out in Chicago during his recovery. Prior to surgery, Waddell underwent a conditioning treatment that consisted of low dose radiation and chemotherapy to weaken his own immune system and make room for the infusion of stem cells.
"The low intensity chemo and radiation conditioning regimen create just enough space for the donor stem cells to gain a foothold in the bone marrow and the donor's immune system takes over," says Dr. Joseph Levanthal, the transplant surgeon who performed the operation and director of kidney and pancreas transplantation at Northwestern University Feinberg School of Medicine. "That way the recipient develops an immune system that doesn't see the donor organ as foreign."
"As a surgeon, I saw what my patients had to go through—taking 25 pills a day, dying at an early age from heart disease, or having a 35% chance of dying every year on dialysis."
A week later, Waddell had the kidney transplant. The following day, he was infused with a complex cellular cocktail that included blood-forming stem cells derived from his donor's bone marrow mixed what are called tolerance inducing facilitator cells (FCs); these cells help the foreign stem cells get established in the recipient's bone marrow.
Over the course of the following year, he was slowly weaned off of antirejection medications—a precaution in case the procedure didn't work—and remarkably, hasn't needed them since. "I felt better than I had in decades because my kidneys [had been] degrading," recalls Waddell, now 54 and a CPA for a global beverage company. And what's even better is that this new approach offers hope for one of his sons who has also inherited the disorder.
Kidney transplants are the most frequent organ transplants in the world and more than 23,000 of these procedures were done in the United States in 2019, according to the United Network for Organ Sharing. Of this, about 7,000 operations are done annually using live organ donors; the remainder use organs from people who are deceased. Right now, this revolutionary new approach—as well as a similar strategy formulated by Stanford University scientists--is in the final phase of clinical trials. Ultimately, this research may pave the way towards realizing the holy grail of organ transplantation: preventing organ rejection by creating a tolerant state in which the recipient's immune system is compatible with the donor, which would eliminate the need for a lifetime of medications.
"As a surgeon, I saw what my patients had to go through—taking 25 pills a day, dying at an early age from heart disease, or having a 35% chance of dying every year on dialysis," says Dr. Suzanne Ildstad, a transplant surgeon and director of the Institute for Cellular Therapeutics at the University of Louisville, whose discovery of facilitator cells were the basis for this therapeutic platform. Ildstad, who has spent more than two decades searching for a better way, says, "This is something I have worked for my entire life."
The Louisville group uses a combination of chemo and radiation to replace the recipient's immune and blood forming cells with that of the donor. In contrast, the Stanford protocol involves harvesting the donor's blood stem cells and T-cells, which are the foot soldiers of the immune system that fight off infections and would normally orchestrate the rejection of the transplanted organ. Their transplant recipients undergo a milder form of "conditioning" that only radiates discrete parts of the body and selectively targets the recipient's T-cells, creating room for both sets of T-cells, a strategy these researchers believe has a better safety profile and less of a chance of rejection.
"We try to achieve immune tolerance by a true chimerism," says Dr. Samuel Strober, a professor of medicine for immunology and rheumatology at Stanford University and a leader of this research team. "The recipients immune system cells are maintained but mixed in the blood with that of the donor."
Studies suggest both approaches work. In a 2018 clinical trial conducted by Talaris Therapeutics, a Louisville-based biotech founded by Ildstad, 26 of 37 (70%) of the live donor kidney transplant recipients no longer need immunosuppressants. Last fall, Talaris began the final phase of clinical tests that will eventually encompass more than 120 such patients.
The Stanford group's cell-based immunotherapy, which is called MDR-101 and is sponsored by the South San Francisco biotech, Medeor Therapeutics, has had similar results in patients who received organs from live donors who were either well matched, such as one from siblings, meaning they were immunologically identical, or partially matched; Talaris uses unrelated donors where there is only a partial match.
In their 2020 clinical trial of 51 patients, 29 were fully matched and 22 were a partial match; 22 of the fully matched recipients didn't need antirejection drugs and ten of the partial matches were able to stop taking some of these medications without rejection. "With our fully matched, roughly 80% have been completely off drugs up to 14 years later," says Strober, "and reducing the number of drugs from three to one [in the partial matches] means you have far fewer side effects. The goal is to get them off of all drugs."
But these protocols are limited to a small number of patients—living donor kidney recipients. As a consequence, both teams are experimenting with ways to broaden their approach so they can use cadaver organs from deceased donors, with human tests planned in the coming year. Here's how that would work: after the other organs are removed from a deceased donor, stem cells are harvested from the donor's vertebrae in the spinal column and then frozen for storage.
"We do the transplant and give the patient a chance to recover and maintain them on drugs," says Ildstad. "Then we do the tolerance conditioning at a later stage."
If this strategy is successful, it would be a genuine game changer, and open the door to using these protocols for transplanting other cadaver organs, including the heart, lungs and liver. While the overall procedure is complex and costly, in the long run it's less expensive than repeated transplant surgeries, the cost of medications and hospitalizations for complications caused by the drugs, or thrice weekly dialysis treatments, says Ildstad.
And she adds, you can't put a price tag on the vast improvement in quality of life.
By mid-March, Alpha Lee was growing restless. A pioneer of AI-driven drug discovery, Lee leads a team of researchers at the University of Cambridge, but his lab had been closed amidst the government-initiated lockdowns spreading inexorably across Europe.
If the Moonshot proves successful, they hope it could serve as a future benchmark for finding new medicines for chronic diseases.
Having spoken to his collaborators across the globe – many of whom were seeing their own experiments and research projects postponed indefinitely due to the pandemic – he noticed a similar sense of frustration and helplessness in the face of COVID-19.
While there was talk of finding a novel treatment for the virus, Lee was well aware the process was likely to be long and laborious. Traditional methods of drug discovery risked suffering the same fate as the efforts to find a cure for SARS in the early 2000, which took years and were ultimately abandoned long before a drug ever reached the market.
To avoid such an outcome, Lee was convinced that global collaboration was required. Together with a collection of scientists in the UK, US and Israel, he launched the 'COVID Moonshot' – a project which encouraged chemists worldwide to share their ideas for potential drug designs. If the Moonshot proves successful, they hope it could serve as a future benchmark for finding new medicines for chronic diseases.
Solving a Complex Jigsaw
In February, ShanghaiTech University published the first detailed snapshots of the SARS-CoV-2 coronavirus's proteins using a technique called X-ray crystallography. In particular, they revealed a high-resolution profile of the virus's main protease – the part of its structure that enables it to replicate inside a host – and the main drug target. The images were tantalizing.
"We could see all the tiny pieces sitting in the structure like pieces of a jigsaw," said Lee. "All we needed was for someone to come up with the best idea of joining these pieces together with a drug. Then you'd be left with a strong molecule which sits in the protease, and stops it from working, killing the virus in the process."
Normally, ideas for how best to design such a drug would be kept as carefully guarded secrets within individual labs and companies due to their potential value. But as a result, the steady process of trial and error to reach an optimum design can take years to come to fruition.
However, given the scale of the global emergency, Lee felt that the scientific community would be open to collective brainstorming on a mass scale. "Big Pharma usually wouldn't necessarily do this, but time is of the essence here," he said. "It was a case of, 'Let's just rethink every drug discovery stage to see -- ok, how can we go as fast as we can?'"
On March 13, he launched the COVID moonshot, calling for chemists around the globe to come up with the most creative ideas they could think of, on their laptops at home. No design was too weird or wacky to be considered, and crucially nothing would be patented. The entire project would be done on a not-for-profit basis, meaning that any drug that makes it to market will have been created simply for the good of humanity.
It caught fire: Within just two weeks, more than 2,300 potential drug designs had been submitted. By the middle of July, over 10,000 had been received from scientists around the globe.
The Road Toward Clinical Trials
With so many designs to choose from, the team has been attempting to whittle them down to a shortlist of the most promising. Computational drug discovery experts at Diamond and the Weizmann Institute of Science in Rehovot, Israel, have enabled the Moonshot team to develop algorithms for predicting how quick and easy each design would be to make, and to predict how well each proposed drug might bind to the virus in real life.
The latter is an approach known as computational covalent docking and has previously been used in cancer research. "This was becoming more popular even before COVID-19, with several covalent drugs approved by the FDA in recent years," said Nir London, professor of organic chemistry at the Weizmann Institute, and one of the Moonshot team members. "However, all of these were for oncology. A covalent drug against SARS-CoV-2 will certainly highlight covalent drug-discovery as a viable option."
Through this approach, the team have selected 850 compounds to date, which they have manufactured and tested in various preclinical trials already. Fifty of these compounds - which appear to be especially promising when it comes to killing the virus in a test tube – are now being optimized further.
Lee is hoping that at least one of these potential drugs will be shown to be effective in curing animals of COVID-19 within the next six months, a step that would allow the Moonshot team to reach out to potential pharmaceutical partners to test their compounds in humans.
Future Implications
If the project does succeed, some believe it could open the door to scientific crowdsourcing as a future means of generating novel medicine ideas for other diseases. Frank von Delft, professor of protein science and structural biology at the University of Oxford's Nuffield Department of Medicine, described it as a new form of 'citizen science.'
"There's a vast resource of expertise and imagination that is simply dying to be tapped into," he said.
Others are slightly more skeptical, pointing out that the uniqueness of the current crisis has meant that many scientists were willing to contribute ideas without expecting any future compensation in return. This meant that it was easy to circumvent the traditional hurdles that prevent large-scale global collaborations from happening – namely how to decide who will profit from the final product and who will hold the intellectual property (IP) rights.
"I think it is too early to judge if this is a viable model for future drug discovery," says London. "I am not sure that without the existential threat we would have seen so many contributions, and so many people and institutions willing to waive compensation and future royalties. Many scientists found themselves at home, frustrated that they don't have a way to contribute to the fight against COVID-19, and this project gave them an opportunity. Plus many can get behind the fact that this project has no associated IP and no one will get rich off of this effort. This breaks down a lot of the typical barriers and red-tape for wider collaboration."
"If a drug would sprout from one of these crowdsourced ideas, it would serve as a very powerful argument to consider this mode of drug discovery further in the future."
However the Moonshot team believes that if they can succeed, it will at the very least send a strong statement to policy makers and the scientific community that greater efforts should be made to make such large-scale collaborations more feasible.
"All across the scientific world, we've seen unprecedented adoption of open-science, collaboration and collegiality during this crisis, perhaps recognizing that only a coordinated global effort could address this global challenge," says London. "If a drug would sprout from one of these crowdsourced ideas, it would serve as a very powerful argument to consider this mode of drug discovery further in the future."
[An earlier version of this article was published on June 8th, 2020 as part of a standalone magazine called GOOD10: The Pandemic Issue. Produced as a partnership among LeapsMag, The Aspen Institute, and GOOD, the magazine is available for free online.]
World’s First “Augmented Reality” Contact Lens Aims to Revolutionize Much More Than Medicine
Imagine a world without screens. Instead of endlessly staring at your computer or craning your neck down to scroll through social media feeds and emails, information simply appears in front of your eyes when you need it and disappears when you don't.
"The vision is super clear...I was reading the poem with my eyes closed."
No more rude interruptions during dinner, no more bumping into people on the street while trying to follow GPS directions — just the information you want, when you need it, projected directly onto your visual field.
While this screenless future sounds like science fiction, it may soon be a reality thanks to the new Silicon Valley startup Mojo Vision, creator of the world's first smart contact lens. With a 14,000 pixel-per-inch display with eye-tracking, image stabilization, and a custom wireless radio, the Mojo smart lens bills itself the "smallest and densest dynamic display ever made." Unlike current augmented reality wearables such as Google Glass or ThirdEye, which project images onto a glass screen, the Mojo smart lens can project images directly onto the retina.
A current prototype displayed at the Consumer Electronics Show earlier this year in Las Vegas includes a tiny screen positioned right above the most sensitive area of the pupil. "[The Mojo lens] is a contact lens that essentially has wireless power and data transmission for a small micro LED projector that is placed over the center of the eye," explains David Hobbs, Director of Product Management at Mojo Vision. "[It] displays critical heads-up information when you need it and fades into the background when you're ready to continue on with your day."
Eventually, Mojo Visions' technology could replace our beloved smart devices but the first generation of the Mojo smart lens will be used to help the 2.2 billion people globally who suffer from vision impairment.
"If you think of the eye as a camera [for the visually impaired], the sensors are not working properly," explains Dr. Ashley Tuan, Vice President of Medical Devices at Mojo Vision and fellow of the American Academy of Optometry. "For this population, our lens can process the image so the contrast can be enhanced, we can make the image larger, magnify it so that low-vision people can see it or we can make it smaller so they can check their environment." In January of this year, the FDA granted Breakthrough Device Designation to Mojo, allowing them to have early and frequent discussions with the FDA about technical, safety and efficacy topics before clinical trials can be done and certification granted.
For now, Dr. Tuan is one of the few people who has actually worn the Mojo lens. "I put the contact lens on my eye. It was very comfortable like any contact lenses I've worn before," she describes. "The vision is super clear and then when I put on the accessories, suddenly I see Yoda in front of me and I see my vital signs. And then I have my colleague that prepared a beautiful poem that I loved when I was young [and] I was reading the poem with my eyes closed."
At the moment, there are several electronic glasses on the market like Acesight and Nueyes Pro that provide similar solutions for those suffering from visual impairment, but they are large, cumbersome, and highly visible. Mojo lens would be a discreet, more comfortable alternative that offers users more freedom of movement and independence.
"In the case of augmented-reality contact lenses, there could be an opportunity to improve the lives of people with low vision," says Dr. Thomas Steinemann, spokesperson for the American Academy of Ophthalmology and professor of ophthalmology at MetroHealth Medical Center in Cleveland. "There are existing tools for people currently living with low vision—such as digital apps, magnifiers, etc.— but something wearable could provide more flexibility and significantly more aid in day-to-day tasks."
As one of the first examples of "invisible computing," the potential applications of Mojo lens in the medical field are endless.
According to Dr. Tuan, the visually impaired often suffer from depression due to their lack of mobility and 70 percent of them are underemployed. "We hope that they can use this device to gain their mobility so they can get that social aspect back in their lives and then, eventually, employment," she explains. "That is our first and most important goal."
But helping those with low visual capabilities is only Mojo lens' first possible medical application; augmented reality is already being used in medicine and is poised to revolutionize the field in the coming decades. For example, Accuvein, a device that uses lasers to provide real-time images of veins, is widely used by nurses and doctors to help with the insertion of needles for IVs and blood tests.
According to the National Center for Biotechnology Information, augmentation of reality has been used in surgery for many years with surgeons using devices such as Google Glass to overlay critical information about their patients into their visual field. Using software like the Holographic Navigation Platform by Scopsis, surgeons can see a mixed-reality overlay that can "show you complicated tumor boundaries, assist with implant placements and guide you along anatomical pathways," its developers say.
However, according to Dr. Tuan, augmented reality headsets have drawbacks in the surgical setting. "The advantage of [Mojo lens] is you don't need to worry about sweating or that the headset or glasses will slide down to your nose," she explains "Also, our lens is designed so that it will understand your intent, so when you don't want the image overlay it will disappear, it will not block your visual field, and when you need it, it will come back at the right time."
As one of the first examples of "invisible computing," the potential applications of Mojo lens in the medical field are endless. Possibilities include live translation of sign language for deaf people; helping those with autism to read emotions; and improving doctors' bedside manner by allowing them to fully engage with patients without relying on a computer.
"[By] monitoring those blood vessels we can [track] chronic disease progression: high blood pressure, diabetes, and Alzheimer's."
Furthermore, the lens could be used to monitor health issues. "We have image sensors in the lens right now that point to the world but we can have a camera pointing inside of your eye to your retina," says Dr. Tuan, "[By] monitoring those blood vessels we can [track] chronic disease progression: high blood pressure, diabetes, and Alzheimer's."
For the moment, the future medical applications of the Mojo lens are still theoretical, but the team is confident they can eventually become a reality after going through the proper regulatory review. The company is still in the process of design, prototype and testing of the lens, so they don't know exactly when it will be available for use, but they anticipate shipping the first available products in the next couple of years. Once it does go to market, it will be available by prescription only for those with visual impairments, but the team's goal is to bring it to broader consumer markets pending regulatory clearance.
"We see that right now there's a unique opportunity here for Mojo lens and invisible computing to help to shape what the next decade of technology development looks like," explains David Hobbs. "We can use [the Mojo lens] to better serve us as opposed to us serving technology better."