This project is jointly funded by Sparks and charity partner Great Ormond Street Hospital Children’s Charity through the National Research Funding Call.
When children have heart-transplants, the surgeon must remove their thymus, a gland where white blood cells called T-cells are made, to gain access to the heart. T-cells help us fight infections, including carefully controlling how and when the immune system responds to invaders like bacteria or viruses. They are also the cells that can cause a body to reject transplants – because the cells or tissue are seen as ‘foreign’.
Because children who have transplants also lack a thymus, this can also cause additional complications, including other effects on the wider immune system. The average survival for a transplanted heart is 20 years, so currently, all children who receive a heart-transplant will need re-transplanting as young adults.
Professor Tessa Crompton from Great Ormond Street Hospital Institute of Child Health wants to improve the short- and long-term success of heart transplants.
Her team want to understand if also transplanting thymus tissue from the donor, along with the heart, could help stop the recipients’ immune system from attacking the transplanted tissue. They will also test whether reintroducing part of the patient’s own thymus after surgery will help recover normal immune system behaviour more broadly. They will initially test this in animal models to ensure it will be safe in children.
If successful, this project will provide better approaches to heart transplants in those children who need them. This could also potentially help children who need other solid organ transplants, such as kidney transplants. These new approaches could prolong the life of the transplanted organ, allowing children to avoid undergoing major surgery again for longer. It could also reduce the need for drugs that stop the patient’s immune system from attacking the transplanted organ and improve a child’s overall immune system after transplant.
Using a tissue of the immune system (the thymus) to improve the success of heart transplants
Researcher: Professor Tessa Crompton