ZURICH: New research on the long-term behavior of transplanted stem cells in the body reveals how aging impacts stem cell survival and immune diversity, providing insights that could improve the safety and success of transplants.
For the first time, scientists have traced the long-term fate of stem cells decades after a transplant, unveiling insights into a medical procedure that has remained a mystery for more than 50 years.
Insights could pave the way for new strategies in donor selection and transplant success, potentially leading to safer, more effective transplants.
Researchers from the Wellcome Sanger Institute and their collaborators at the University of Zurich were able to map the behavior of stem cells in recipients’ bodies up to three decades post-transplant, providing the first-ever glimpse into the long-term dynamics of these cells.
The study, published in Nature and part-funded by Cancer Research UK, reveals that transplants from older donors, which are often less successful, have ten times fewer vital stem cells surviving the transplant process. Some of the surviving cells also lose the ability to produce the range of blood cells essential for a robust immune system.
Over a million people worldwide are diagnosed with blood cancer each year, including cancers such as leukemia and lymphoma, which can stop a person’s immune system from working properly. Stem cell transplants, also known as bone marrow transplants, are often the only curative treatment option for patients. The procedure replaces a patient’s damaged blood cells with healthy stem cells from a donor, which then rebuilds the patient’s entire blood and immune system. In the UK alone, over 2,000 people undergo this procedure each year.
The Cellular Mystery of Transplants
Despite being performed for over 50 years, many fundamental questions about how transplants work have remained unanswered. While they can be life-saving, outcomes vary widely, leaving many patients facing complications years later. Donor age has been known to impact success rates, but what happens at the cellular level following a transplant has been a ‘black box’, until now.
In this new study, researchers from the Wellcome Sanger Institute and the University of Zurich used advanced genome sequencing techniques to analyze blood samples from ten donor-recipient sibling pairs up to 31 years post-transplant.
