Study on Liver Transplants Shows Promise

On Friday, researchers from the University of Pittsburgh announced they have successfully trained some patients’ immune systems to accept liver transplants without the need for anti-rejection drugs. This approach, which has long been sought after in the field of transplantation, saw three out of eight patients off the medication for at least three years. The findings were published in Nature Communications.

Dr. William Jarnagin, a cancer surgeon at Memorial Sloan Kettering Cancer Center, stated that the team has made significant progress in validating this principle independently of his involvement. He expressed optimism, saying that with ongoing development, this could reshape the landscape of organ transplants.

Dr. Joohyun Kim, a liver transplant surgeon at Yale, echoed these thoughts, remarking that just a decade ago, the concept of “tolerance induction” seemed like an unrealistic aspiration.

While anti-rejection medications enable organ transplants, they come with serious risks. These drugs suppress the immune system, which can lead to increased susceptibility to infections, cancers, high cholesterol, heart disease, diabetes, and kidney problems. Some patients even experience hair loss as a side effect.

Sadly, about 25 percent of liver transplant patients die within five years, and many require kidney transplants as the anti-rejection medications can harm those organs. “The long list of adverse effects is daunting,” said Dr. Abhinav Humar, who leads abdominal transplant services at the University of Pittsburgh Medical Center. “If there were a way to avoid them, we certainly would.”

Research into reducing the reliance on these drugs has been ongoing for nearly 30 years, according to Dr. Angus Thomson, a professor of surgery and immunology at the University of Pittsburgh.

The study highlights the potential of dendritic cells, which play a crucial role in helping the immune system differentiate between self and non-self. The researchers proposed that by introducing dendritic cells from the donor to the recipient, the latter might learn to accept the new organ more readily.

The decision to focus on liver transplants stemmed from the idea that livers tend to be more easily accepted than kidneys. After years of taking immunosuppressive drugs, around 13 to 15 percent of liver transplant patients are able to stop without their immune systems attacking the new organ.

Additionally, the team opted to use living donors, as the liver can regenerate. In many cases, a healthy portion of the donor’s liver can be transplanted, allowing both donor and recipient to grow back full livers.

This method allowed for the donor’s dendritic cells to be given to the recipient prior to the transplant. This timing was intended to prepare the recipient’s immune system to accept the liver. There’s even a possibility of applying this with deceased donors, though it would require infusing dendritic cells a week following the transplantation.

The first participant in this study, Michael Schaffer, received his donor’s dendritic cells before his liver transplant in October 2017, but sadly passed away eight years later from unrelated issues. He remained on a minimal dose of one anti-rejection medication but could not completely stop taking it.

On a more positive note, another patient, Barbara Bowser, experienced a much better outcome. A retired school cleaner from Punxsutawney, Pennsylvania, she was unaware of her liver issues until a serious incident in December 2016, which forced her to seek a transplant.

Desperate for a living donor, she shared her story on Facebook, leading a 33-year-old woman to offer her liver. On the day of the surgery, they met for the first time. One week earlier, Barbara had received the dendritic cells.

Following the transplant on January 25, 2018, Barbara took anti-rejection drugs for nine months, finding them intolerable—they impacted her health and caused her hair to fall out. While initially cautious, the doctors eventually helped her taper off the medication in October 2019, and she feared for her health during this transition. “I never thought it would work,” she admitted.

Today, six and a half years later, Barbara is still thriving with her transplanted liver without any medication. “I feel like my old self,” she shared, reflecting the hope that this new approach could change lives for many others in need of transplants.