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.
Meet the Psychologist Using Psychedelics to Treat Racial Trauma
Monnica Williams was stuck. The veteran psychologist wanted to conduct a study using psychedelics, but her university told her they didn't have the expertise to evaluate it via an institutional review board, which is responsible for providing ethical and regulatory oversight for research that involves human participants. Instead, they directed her to a hospital, whose reviewers turned it down, citing research of a banned substance as unethical.
"I said, 'We're not using illegal psilocybin, we're going through Health Canada,'" Williams said. Psilocybin was banned in Canada in 1974, but can now be obtained with an exemption from Health Canada, the federal government's health policy department. After learning this, the hospital review board told Williams they couldn't review her proposal because she's not affiliated with the hospital, after all.
It's all part of balancing bureaucracy with research goals for Williams, a leading expert on racial trauma and psychedelic medicine, as well as obsessive compulsive disorder (OCD), at the University of Ottawa. She's exploring the use of hallucinogenic substances like MDMA and psilocybin — commonly known as ecstasy and magic mushrooms, respectively — to help people of color address the psychological impacts of systemic racism. A prolific researcher, Williams also works as an expert witness, offering clinical evaluations for racial trauma cases.
Scientists have long known that psychedelics produce an altered state of consciousness and openness to new perspectives. For people with mental health conditions who haven't benefited from traditional therapy, psychedelics may be able to help them discover what's causing their pain or trauma, including racial trauma—the mental and emotional injury spurred by racial bias.
"Using psychedelics can not only bring these pain points to the surface for healing, but can reduce the anxiety or response to these memories and allow them to speak openly about them without the pain they bring," Williams says. Her research harnesses the potential of psychedelics to increase neuroplasticity, which includes the brain's ability to build new pathways.
"People of color are dealing with racism all the time, in large and small ways, and even dealing with racism in healthcare, even dealing with racism in therapy."
But she says therapists of color aren't automatically equipped to treat racial trauma. First, she notes, people of color are "vastly underrepresented in the mental health workforce." This is doubly true in psychedelic-assisted psychotherapy, in which a person is guided through a psychedelic session by a therapist or team of therapists, then processes the experience in subsequent therapy sessions.
"On top of that, the therapists of color are getting the same training that the white therapists are getting, so it's not even really guaranteed that they're going to be any better at helping a person that may have racial trauma emerging as part of their experience," she says.
In her own training to become a clinical psychologist at the University of Virginia, Williams says she was taught "how to be a great psychologist for white people." Yet even people of color, she argues, need specialized training to work with marginalized groups, particularly when it comes to MDMA, psilocybin and other psychedelics. Because these drugs can lower natural psychological defense mechanisms, Williams says, it's important for providers to be specially trained.
"People of color are dealing with racism all the time, in large and small ways, and even dealing with racism in healthcare, even dealing with racism in therapy. So [they] generally develop a lot of defenses and coping strategies to ward off racism so that they can function." she says. This is particularly true with psychedelic-assisted psychotherapy: "One possibility is that you're going to be stripped of your defenses, you're going to be vulnerable. And so you have to work with a therapist who is going to understand that and not enact more racism in their work with you."
Williams has struggled to find funding and institutional approval for research involving psychedelics, or funding for investigations into racial trauma or the impacts of conditions like OCD and post-traumatic stress disorder (PTSD) in people of color. With the bulk of her work focusing on OCD, she hoped to focus on people of color, but found there was little funding for that type of research. In 2020, that started to change as structural racism garnered more media attention.
After the killing of George Floyd, a 46-year-old Black man, by a white police officer in May 2020, Williams was flooded with media requests. "Usually, when something like that happens, I get contacted a lot for a couple of weeks, and it dies off. But after George Floyd, it just never did."
Monnica Williams, clinical psychologist at the University of Ottawa
Williams was no stranger to the questions that soon blazed across headlines: How can we mitigate microaggressions? How do race and ethnicity impact mental health? What terms should we use to discuss racial issues? What constitutes an ally, and why aren't there more of them? Why aren't there more people of color in academia, and so many other fields?
Now, she's hoping that the increased attention on racial justice will mean more acceptance for the kind of research she's doing.
In fact, Williams herself has used psychedelics in order to gain a better understanding of how to use them to treat racial trauma. In a study published in January, she and two other Black female psychotherapists took MDMA in a supervised setting, guided by a team of mental health practitioners who helped them process issues that came up as the session progressed. Williams, who was also the study's lead author, found that participants' experiences centered around processing and finding release from racial identities, and, in one case, of simply feeling wholly human without the burden of racial identity for the first time.
The purpose of the study was twofold: to understand how Black women react to psychedelics and to provide safe, firsthand, psychedelic experiences to Black mental health practitioners. One of the other study participants has since gone on to offer psychedelic-assisted psychotherapy to her own patients.
Psychedelic research, and psilocybin in particular, has become a hot topic of late, particularly after Oregon became the first state to legalize it for therapeutic use last November. A survey-based, observational study with 313 participants, published in 2020, paved the way for Williams' more recent MDMA experiments by describing improvements in depression, anxiety and racial trauma among people of color who had used LSD, psilocybin or MDMA in a non-research setting.
Williams and her team included only respondents who reported a moderate to strong psychoactive effect of past psychedelic consumption and believed these experiences provided "relief from the challenging effects of ethnic discrimination." Participants reported a memorable psychedelic experience as well as its acute and lasting effects, completing assessments of psychological insight, mystical experience and emotional challenges experienced during psychedelic experience, then describing their mental health — including depression, anxiety and trauma symptoms — before and after that experience.
Still, Williams says addressing racism is much more complex than treating racial trauma. "One of the questions I get asked a lot is, 'How can Black people cope with racism?' And I don't really like that question," she says. "I think it's important and I don't mind answering it, but I think the more important question is, how can we end racism? What can Black people do to stop racism that's happening to them and what can we do as a society to stop racism? And people aren't really asking this question."
Tiny, Injectable Robots Could Be the Future of Brain Treatments
In the 1966 movie "Fantastic Voyage," actress Raquel Welch and her submarine were shrunk to the size of a cell in order to eliminate a blood clot in a scientist's brain. Now, 55 years later, the scenario is becoming closer to reality.
California-based startup Bionaut Labs has developed a nanobot about the size of a grain of rice that's designed to transport medication to the exact location in the body where it's needed. If you think about it, the conventional way to deliver medicine makes little sense: A painkiller affects the entire body instead of just the arm that's hurting, and chemotherapy is flushed through all the veins instead of precisely targeting the tumor.
"Chemotherapy is delivered systemically," Bionaut-founder and CEO Michael Shpigelmacher says. "Often only a small percentage arrives at the location where it is actually needed."
But what if it was possible to send a tiny robot through the body to attack a tumor or deliver a drug at exactly the right location?
Several startups and academic institutes worldwide are working to develop such a solution but Bionaut Labs seems the furthest along in advancing its invention. "You can think of the Bionaut as a tiny screw that moves through the veins as if steered by an invisible screwdriver until it arrives at the tumor," Shpigelmacher explains. Via Zoom, he shares the screen of an X-ray machine in his Culver City lab to demonstrate how the half-transparent, yellowish device winds its way along the spine in the body. The nanobot contains a tiny but powerful magnet. The "invisible screwdriver" is an external magnetic field that rotates that magnet inside the device and gets it to move and change directions.
The current model has a diameter of less than a millimeter. Shpigelmacher's engineers could build the miniature vehicle even smaller but the current size has the advantage of being big enough to see with bare eyes. It can also deliver more medicine than a tinier version. In the Zoom demonstration, the micorobot is injected into the spine, not unlike an epidural, and pulled along the spine through an outside magnet until the Bionaut reaches the brainstem. Depending which organ it needs to reach, it could be inserted elsewhere, for instance through a catheter.
"The hope is that we can develop a vehicle to transport medication deep into the body."
Imagine moving a screw through a steak with a magnet — that's essentially how the device works. But of course, the Bionaut is considerably different from an ordinary screw: "At the right location, we give a magnetic signal, and it unloads its medicine package," Shpigelmacher says.
To start, Bionaut Labs wants to use its device to treat Parkinson's disease and brain stem gliomas, a type of cancer that largely affects children and teenagers. About 300 to 400 young people a year are diagnosed with this type of tumor. Radiation and brain surgery risk damaging sensitive brain tissue, and chemotherapy often doesn't work. Most children with these tumors live less than 18 months. A nanobot delivering targeted chemotherapy could be a gamechanger. "These patients really don't have any other hope," Shpigelmacher says.
Of course, the main challenge of the developing such a device is guaranteeing that it's safe. Because tissue is so sensitive, any mistake could risk disastrous results. Over the past four years, Bionaut has tested its technology in dozens of healthy sheep and pigs with no major adverse effects. Sheep make a good stand-in for humans because their brains and spines are similar to ours.
The Bionaut device is about the size of a grain of rice.
Bionaut Labs
"As the Bionaut moves through brain tissue, it creates a transient track that heals within a few weeks," Shpigelmacher says. The company is hoping to be the first to test a nanobot in humans. That could happen as early as 2023, Shpigelmacher says.
Once the technique has been perfected, further applications could include addressing other kinds of brain disorders that are considered incurable now, such as Alzheimer's or Huntington's disease. "Microrobots could serve as a bridgehead, opening the gateway to the brain and facilitating precise access of deep brain structure – either to deliver medication, take cell samples or stimulate specific brain regions," Shpigelmacher says.
Robot-assisted hybrid surgery with artificial intelligence is already used in state-of-the-art surgery centers, and many medical experts believe that nanorobotics will be the instrument of the future. In 2016, three scientists were awarded the Nobel Prize in Chemistry for their development of "the world's smallest machines," nano "elevators" and minuscule motors. Since then, the scientific experiments have progressed to the point where applicable devices are moving closer to actually being implemented.
Bionaut's technology was initially developed by a research team lead by Peer Fischer, head of the independent Micro Nano and Molecular Systems Lab at the Max Planck Institute for Intelligent Systems in Stuttgart, Germany. Fischer is considered a pioneer in the research of nano systems, which he began at Harvard University more than a decade ago. He and his team are advising Bionaut Labs and have licensed their technology to the company.
"The hope is that we can develop a vehicle to transport medication deep into the body," says Max Planck scientist Tian Qiu, who leads the cooperation with Bionaut Labs. He agrees with Shpigelmacher that the Bionaut's size is perfect for transporting medication loads and is researching potential applications for even smaller nanorobots, especially in the eye, where the tissue is extremely sensitive. "Nanorobots can sneak through very fine tissue without causing damage."
In "Fantastic Voyage," Raquel Welch's adventures inside the body of a dissident scientist let her swim through his veins into his brain, but her shrunken miniature submarine is attacked by antibodies; she has to flee through the nerves into the scientist's eye where she escapes into freedom on a tear drop. In reality, the exit in the lab is much more mundane. The Bionaut simply leaves the body through the same port where it entered. But apart from the dramatization, the "Fantastic Voyage" was almost prophetic, or, as Shpigelmacher says, "Science fiction becomes science reality."