Fran Leier

Supervisor: Lori West

Project: Increasing the safety of ABO-mismatched heart transplants

“It is a privilege to be immersed in an environment with intelligent and kind people willing to share the wisdom they have gathered along their careers.”

Donor organ shortage is a major problem for children needing transplants. Hearts from donors with ABO blood groups mismatched to the recipient would increase access, but this is generally not done because ABO antibodies, if not removed, cause rapid rejection. The West lab showed that infants and young children can safely receive ABO-mismatched transplants because they have immature immune systems and have not yet made ABO antibodies. This has resulted in more donors for children, allowing life-saving heart transplants around the world.    

Safe ABO-mismatched transplantation in older children requires accurate detection of ABO antibodies. These are still measured with the 'hemagglutination' test (red blood cell clumping), that was developed more than 100 years ago and has known flaws. This test works well for blood transfusions, but it is less helpful for transplant testing and decision-making. Recently, the West lab developed a 'bead-based' test that is faster and easier to use. Because it is similar to tests already commonly used to detect other transplant antibodies, it is easier for clinical laboratories to start using this new test. 

For my project this summer, I will use this test to help determine normal ranges of ABO antibodies throughout childhood. We will do this by testing stored blood samples from children on the waiting list for a heart transplant. We will also test stored samples from a range of ages of children not needing a heart transplant. From this project, we will have a better understanding of the normal ranges and development of ABO antibodies in children. This knowledge and the improved ABO antibody detection method will increase the predictability and safety of ABO-mismatched heart transplantation. Precise determination of ABO antibodies will help with the consideration of expansion of ABO-mismatched heart transplantation for older children.

Fran Leier was supervised by Lori West and her summer studentship was funded by the Stollery Children’s Hospital Foundation. She is enrolled in the Bachelor of Science with Specialization in Immunology and Infection program.