Scientists are making machines, wearable and implantable, to act as kidneys
Like all those whose kidneys have failed, Scott Burton’s life revolves around dialysis. For nearly two decades, Burton has been hooked up (or, since 2020, has hooked himself up at home) to a dialysis machine that performs the job his kidneys normally would. The process is arduous, time-consuming, and expensive. Except for a brief window before his body rejected a kidney transplant, Burton has depended on machines to take the place of his kidneys since he was 12-years-old. His whole life, the 39-year-old says, revolves around dialysis.
“Whenever I try to plan anything, I also have to plan my dialysis,” says Burton says, who works as a freelance videographer and editor. “It’s a full-time job in itself.”
Many of those on dialysis are in line for a kidney transplant that would allow them to trade thrice-weekly dialysis and strict dietary limits for a lifetime of immunosuppressants. Burton’s previous transplant means that his body will likely reject another donated kidney unless it matches perfectly—something he’s not counting on. It’s why he’s enthusiastic about the development of artificial kidneys, small wearable or implantable devices that would do the job of a healthy kidney while giving users like Burton more flexibility for traveling, working, and more.
Still, the devices aren’t ready for testing in humans—yet. But recent advancements in engineering mean that the first preclinical trials for an artificial kidney could happen as soon as 18 months from now, according to Jonathan Himmelfarb, a nephrologist at the University of Washington.
“It would liberate people with kidney failure,” Himmelfarb says.
An engineering marvel
Compared to the heart or the brain, the kidney doesn’t get as much respect from the medical profession, but its job is far more complex. “It does hundreds of different things,” says UCLA’s Ira Kurtz.
Kurtz would know. He’s worked as a nephrologist for 37 years, devoting his career to helping those with kidney disease. While his colleagues in cardiology and endocrinology have seen major advances in the development of artificial hearts and insulin pumps, little has changed for patients on hemodialysis. The machines remain bulky and require large volumes of a liquid called dialysate to remove toxins from a patient’s blood, along with gallons of purified water. A kidney transplant is the next best thing to someone’s own, functioning organ, but with over 600,000 Americans on dialysis and only about 100,000 kidney transplants each year, most of those in kidney failure are stuck on dialysis.
Part of the lack of progress in artificial kidney design is the sheer complexity of the kidney’s job. Each of the 45 different cell types in the kidney do something different.
Part of the lack of progress in artificial kidney design is the sheer complexity of the kidney’s job. To build an artificial heart, Kurtz says, you basically need to engineer a pump. An artificial pancreas needs to balance blood sugar levels with insulin secretion. While neither of these tasks is simple, they are fairly straightforward. The kidney, on the other hand, does more than get rid of waste products like urea and other toxins. Each of the 45 different cell types in the kidney do something different, helping to regulate electrolytes like sodium, potassium, and phosphorous; maintaining blood pressure and water balance; guiding the body’s hormonal and inflammatory responses; and aiding in the formation of red blood cells.
There's been little progress for patients during Ira Kurtz's 37 years as a nephrologist. Artificial kidneys would change that.
UCLA
Dialysis primarily filters waste, and does so well enough to keep someone alive, but it isn’t a true artificial kidney because it doesn’t perform the kidney’s other jobs, according to Kurtz, such as sensing levels of toxins, wastes, and electrolytes in the blood. Due to the size and water requirements of existing dialysis machines, the equipment isn’t portable. Physicians write a prescription for a certain duration of dialysis and assess how well it’s working with semi-regular blood tests. The process of dialysis itself, however, is conducted blind. Doctors can’t tell how much dialysis a patient needs based on kidney values at the time of treatment, says Meera Harhay, a nephrologist at Drexel University in Philadelphia.
But it’s the impact of dialysis on their day-to-day lives that creates the most problems for patients. Only one-quarter of those on dialysis are able to remain employed (compared to 85% of similar-aged adults), and many report a low quality of life. Having more flexibility in life would make a major different to her patients, Harhay says.
“Almost half their week is taken up by the burden of their treatment. It really eats away at their freedom and their ability to do things that add value to their life,” she says.
Art imitates life
The challenge for artificial kidney designers was how to compress the kidney’s natural functions into a portable, wearable, or implantable device that wouldn’t need constant access to gallons of purified and sterilized water. The other universal challenge they faced was ensuring that any part of the artificial kidney that would come in contact with blood was kept germ-free to prevent infection.
As part of last year’s KidneyX Prize, a partnership between the U.S. Department of Health and Human Services and the American Society of Nephrology, inventors were challenged to create prototypes for artificial kidneys. Himmelfarb’s team at the University of Washington’s Center for Dialysis Innovation won the prize by focusing on miniaturizing existing technologies to create a portable dialysis machine. The backpack sized AKTIV device (Ambulatory Kidney to Increase Vitality) will recycle dialysate in a closed loop system that removes urea from blood and uses light-based chemical reactions to convert the urea to nitrogen and carbon dioxide, which allows the dialysate to be recirculated.
Himmelfarb says that the AKTIV can be used when at home, work, or traveling, which will give users more flexibility and freedom. “If you had a 30-pound device that you could put in the overhead bins when traveling, you could go visit your grandkids,” he says.
Kurtz’s team at UCLA partnered with the U.S. Kidney Research Corporation and Arkansas University to develop a dialysate-free desktop device (about the size of a small printer) as the first phase of a progression that will he hopes will lead to something small and implantable. Part of the reason for the artificial kidney’s size, Kurtz says, is the number of functions his team are cramming into it. Not only will it filter urea from blood, but it will also use electricity to help regulate electrolyte levels in a process called electrodeionization. Kurtz emphasizes that these additional functions are what makes his design a true artificial kidney instead of just a small dialysis machine.
One version of an artificial kidney.
UCLA
“It doesn't have just a static function. It has a bank of sensors that measure chemicals in the blood and feeds that information back to the device,” Kurtz says.
Other startups are getting in on the game. Nephria Bio, a spinout from the South Korean-based EOFlow, is working to develop a wearable dialysis device, akin to an insulin pump, that uses miniature cartridges with nanomaterial filters to clean blood (Harhay is a scientific advisor to Nephria). Ian Welsford, Nephria’s co-founder and CTO, says that the device’s design means that it can also be used to treat acute kidney injuries in resource-limited settings. These potentials have garnered interest and investment in artificial kidneys from the U.S. Department of Defense.
For his part, Burton is most interested in an implantable device, as that would give him the most freedom. Even having a regular outpatient procedure to change batteries or filters would be a minor inconvenience to him.
“Being plugged into a machine, that’s not mimicking life,” he says.
On today’s episode of Making Sense of Science, I’m honored to be joined by Dr. Paul Song, a physician, oncologist, progressive activist and biotech chief medical officer. Through his company, NKGen Biotech, Dr. Song is leveraging the power of patients’ own immune systems by supercharging the body’s natural killer cells to make new treatments for Alzheimer’s and cancer.
Whereas other treatments for Alzheimer’s focus directly on reducing the build-up of proteins in the brain such as amyloid and tau in patients will mild cognitive impairment, NKGen is seeking to help patients that much of the rest of the medical community has written off as hopeless cases, those with late stage Alzheimer’s. And in small studies, NKGen has shown remarkable results, even improvement in the symptoms of people with these very progressed forms of Alzheimer’s, above and beyond slowing down the disease.
In the realm of cancer, Dr. Song is similarly setting his sights on another group of patients for whom treatment options are few and far between: people with solid tumors. Whereas some gradual progress has been made in treating blood cancers such as certain leukemias in past few decades, solid tumors have been even more of a challenge. But Dr. Song’s approach of using natural killer cells to treat solid tumors is promising. You may have heard of CAR-T, which uses genetic engineering to introduce cells into the body that have a particular function to help treat a disease. NKGen focuses on other means to enhance the 40 plus receptors of natural killer cells, making them more receptive and sensitive to picking out cancer cells.
Paul Y. Song, MD is currently CEO and Vice Chairman of NKGen Biotech. Dr. Song’s last clinical role was Asst. Professor at the Samuel Oschin Cancer Center at Cedars Sinai Medical Center.
Dr. Song served as the very first visiting fellow on healthcare policy in the California Department of Insurance in 2013. He is currently on the advisory board of the Pritzker School of Molecular Engineering at the University of Chicago and a board member of Mercy Corps, The Center for Health and Democracy, and Gideon’s Promise.
Dr. Song graduated with honors from the University of Chicago and received his MD from George Washington University. He completed his residency in radiation oncology at the University of Chicago where he served as Chief Resident and did a brachytherapy fellowship at the Institute Gustave Roussy in Villejuif, France. He was also awarded an ASTRO research fellowship in 1995 for his research in radiation inducible gene therapy.
With Dr. Song’s leadership, NKGen Biotech’s work on natural killer cells represents cutting-edge science leading to key findings and important pieces of the puzzle for treating two of humanity’s most intractable diseases.
Show links
- Paul Song LinkedIn
- NKGen Biotech on Twitter - @NKGenBiotech
- NKGen Website: https://nkgenbiotech.com/
- NKGen appoints Paul Song
- Patient Story: https://pix11.com/news/local-news/long-island/promising-new-treatment-for-advanced-alzheimers-patients/
- FDA Clearance: https://nkgenbiotech.com/nkgen-biotech-receives-ind-clearance-from-fda-for-snk02-allogeneic-natural-killer-cell-therapy-for-solid-tumors/Q3 earnings data: https://www.nasdaq.com/press-release/nkgen-biotech-inc.-reports-third-quarter-2023-financial-results-and-business
Is there a robot nanny in your child's future?
From ROBOTS AND THE PEOPLE WHO LOVE THEM: Holding on to Our Humanity in an Age of Social Robots by Eve Herold. Copyright © 2024 by the author and reprinted by permission of St. Martin’s Publishing Group.
Could the use of robots take some of the workload off teachers, add engagement among students, and ultimately invigorate learning by taking it to a new level that is more consonant with the everyday experiences of young people? Do robots have the potential to become full-fledged educators and further push human teachers out of the profession? The preponderance of opinion on this subject is that, just as AI and medical technology are not going to eliminate doctors, robot teachers will never replace human teachers. Rather, they will change the job of teaching.
A 2017 study led by Google executive James Manyika suggested that skills like creativity, emotional intelligence, and communication will always be needed in the classroom and that robots aren’t likely to provide them at the same level that humans naturally do. But robot teachers do bring advantages, such as a depth of subject knowledge that teachers can’t match, and they’re great for student engagement.
The teacher and robot can complement each other in new ways, with the teacher facilitating interactions between robots and students. So far, this is the case with teaching “assistants” being adopted now in China, Japan, the U.S., and Europe. In this scenario, the robot (usually the SoftBank child-size robot NAO) is a tool for teaching mainly science, technology, engineering, and math (the STEM subjects), but the teacher is very involved in planning, overseeing, and evaluating progress. The students get an entertaining and enriched learning experience, and some of the teaching load is taken off the teacher. At least, that’s what researchers have been able to observe so far.
To be sure, there are some powerful arguments for having robots in the classroom. A not-to-be-underestimated one is that robots “speak the language” of today’s children, who have been steeped in technology since birth. These children are adept at navigating a media-rich environment that is highly visual and interactive. They are plugged into the Internet 24-7. They consume music, games, and huge numbers of videos on a weekly basis. They expect to be dazzled because they are used to being dazzled by more and more spectacular displays of digital artistry. Education has to compete with social media and the entertainment vehicles of students’ everyday lives.
Another compelling argument for teaching robots is that they help prepare students for the technological realities they will encounter in the real world when robots will be ubiquitous. From childhood on, they will be interacting and collaborating with robots in every sphere of their lives from the jobs they do to dealing with retail robots and helper robots in the home. Including robots in the classroom is one way of making sure that children of all socioeconomic backgrounds will be better prepared for a highly automated age, when successfully using robots will be as essential as reading and writing. We’ve already crossed this threshold with computers and smartphones.
Students need multimedia entertainment with their teaching. This is something robots can provide through their ability to connect to the Internet and act as a centralized host to videos, music, and games. Children also need interaction, something robots can deliver up to a point, but which humans can surpass. The education of a child is not just intended to make them technologically functional in a wired world, it’s to help them grow in intellectual, creative, social, and emotional ways. When considered through this perspective, it opens the door to questions concerning just how far robots should go. Robots don’t just teach and engage children; they’re designed to tug at their heartstrings.
It’s no coincidence that many toy makers and manufacturers are designing cute robots that look and behave like real children or animals, says Turkle. “When they make eye contact and gesture toward us, they predispose us to view them as thinking and caring,” she has written in The Washington Post. “They are designed to be cute, to provide a nurturing response” from the child. As mentioned previously, this nurturing experience is a powerful vehicle for drawing children in and promoting strong attachment. But should children really love their robots?
ROBOTS AND THE PEOPLE WHO LOVE THEM: Holding on to Our Humanity in an Age of Social Robots by Eve Herold (January 9, 2024).
St. Martin’s Publishing Group
The problem, once again, is that a child can be lulled into thinking that she’s in an actual relationship, when a robot can’t possibly love her back. If adults have these vulnerabilities, what might such asymmetrical relationships do to the emotional development of a small child? Turkle notes that while we tend to ascribe a mind and emotions to a socially interactive robot, “simulated thinking may be thinking, but simulated feeling is never feeling, and simulated love is never love.”
Always a consideration is the fact that in the first few years of life, a child’s brain is undergoing rapid growth and development that will form the foundation of their lifelong emotional health. These formative experiences are literally shaping the child’s brain, their expectations, and their view of the world and their place in it. In Alone Together, Turkle asks: What are we saying to children about their importance to us when we’re willing to outsource their care to a robot? A child might be superficially entertained by the robot while his self-esteem is systematically undermined.
Research has emerged showing that there are clear downsides to child-robot relationships.
Still, in the case of robot nannies in the home, is active, playful engagement with a robot for a few hours a day any more harmful than several hours in front of a TV or with an iPad? Some, like Xiong, regard interacting with a robot as better than mere passive entertainment. iPal’s manufacturers say that their robot can’t replace parents or teachers and is best used by three- to eight-year-olds after school, while they wait for their parents to get off work. But as robots become ever-more sophisticated, they’re expected to perform more of the tasks of day-to-day care and to be much more emotionally advanced. There is no question children will form deep attachments to some of them. And research has emerged showing that there are clear downsides to child-robot relationships.
Some studies, performed by Turkle and fellow MIT colleague Cynthia Breazeal, have revealed a darker side to the child-robot bond. Turkle has reported extensively on these studies in The Washington Post and in her book Alone Together. Most children love robots, but some act out their inner bully on the hapless machines, hitting and kicking them and otherwise trying to hurt them. The trouble is that the robot can’t fight back, teaching children that they can bully and abuse without consequences. As in any other robot relationship, such harmful behavior could carry over into the child’s human relationships.
And, ironically, it turns out that communicative machines don’t actually teach kids good communication skills. It’s well known that parent-child communication in the first three years of life sets the stage for a very young child’s intellectual and academic success. Verbal back-and-forth with parents and care-givers is like fuel for a child’s growing brain. One article that examined several types of play and their effect on children’s communication skills, published in JAMA Pediatrics in 2015, showed that babies who played with electronic toys—like the popular robot dog Aibo—show a decrease in both the quantity and quality of their language skills.
Anna V. Sosa of the Child Speech and Language Lab at Northern Arizona University studied twenty-six ten- to sixteen- month-old infants to compare the growth of their language skills after they played with three types of toys: electronic toys like a baby laptop and talking farm; traditional toys like wooden puzzles and building blocks; and books read aloud by their parents. The play that produced the most growth in verbal ability was having books read to them by a caregiver, followed by play with traditional toys. Language gains after playing with electronic toys came dead last. This form of play involved the least use of adult words, the least conversational turntaking, and the least verbalizations from the children. While the study sample was small, it’s not hard to extrapolate that no electronic toy or even more abled robot could supply the intimate responsiveness of a parent reading stories to a child, explaining new words, answering the child’s questions, and modeling the kind of back- and-forth interaction that promotes empathy and reciprocity in relationships.
***
Most experts acknowledge that robots can be valuable educational tools. But they can’t make a child feel truly loved, validated, and valued. That’s the job of parents, and when parents abdicate this responsibility, it’s not only the child who misses out on one of life’s most profound experiences.
We really don’t know how the tech-savvy children of today will ultimately process their attachments to robots and whether they will be excessively predisposed to choosing robot companionship over that of humans. It’s possible their techno literacy will draw for them a bold line between real life and a quasi-imaginary history with a robot. But it will be decades before we see long-term studies culminating in sufficient data to help scientists, and the rest of us, to parse out the effects of a lifetime spent with robots.
This is an excerpt from ROBOTS AND THE PEOPLE WHO LOVE THEM: Holding on to Our Humanity in an Age of Social Robots by Eve Herold. The book will be published on January 9, 2024.