Transplant operations, although potentially life-saving, come with their share of risks. Researchers in Germany have found that one of those risks could be the transfer of allergies from the donor to the transplant recipient.
According to the report published in the Journal of the European Academy of Dermatology and Venereology, a 46-year-old man developed an allergy to kiwifruit after he received a bone marrow transplant from his sister, who is also allergic to the fruit.
This is not the first time doctors have seen patients develop allergies following a bone marrow transplant. But it is the first time they've been able to directly trace the allergy back to a bone marrow donor's cells.
The man received the transplant as treatment for leukemia, a form of blood cancer. During the procedure, doctors removed hematopoietic stem cells (blood stem cells, for short) from the man's sister and transplanted them into him. Blood stem cells are immature cells that are found in the blood and in the bone marrow. They can renew themselves and develop into all other types of blood cells. Doctors hoped the sister's healthy cells would replenish her brother's blood and immune cells.
They did — but with an unintended consequence: On two different occasions following the surgery, the man reported an allergic reaction after eating kiwifruit. According to the report, his lips and mouth itched and burned — the same symptoms his sister experienced after eating the fruit.
To find out what triggered the allergy, doctors isolated the cells in the man's blood that were reacting to the kiwifruit. Using a technique called fluorescent in situ hybridization (FISH), they were able to confirm that the allergic cells were transferred to the man from his sister through her blood cells.
And does this mean that the opposite is also true? Could allergies be cured through bone marrow transplants? Doctors say only time and more research will tell. "So far, our case has no direct implications concerning the treatment of allergies. However, as allergy transfer is possible via stem cell transplantation it seems possible that also curing of allergy via stem cell transplantation is feasible," says Garzorz via email.
She notes that if a bone marrow transplant were used to treat allergies, it would only be for the severest cases where the patient has exhausted all other options, as stem cell transplantation is an extremely high-risk medical procedure.