He may have loved to eat kiwifruit. He may have been indifferent towards the fuzzy green egg-shaped things. He may not have liked them at all. But, whatever his attitude towards the innocent-looking berries was, he was not allergic to them. That is, until, at age 26, he needed a bone marrow transplant to battle acute lymphocytic leukemia. His sister turned out to be a matching donor, and the transplantation was a success. It kept the leukemia in check.
But, as it turned out, it also transferred his sister’s kiwifruit allergy to him. Transfers of allergies after bone marrow transplantation have been observed before.  What had been missing, to date, was proof that the allergy in the recipient was in fact mediated by the transferred hematopoietic stem cells. That proof is now given. A recent report by a group of scientists at the Technical University in Munich, Germany, shows, for the first time, that the allergy transfer was indeed caused by the donor’s hematopoietic stem cells. 
The researchers exploited the fortuitous coincidence that the donor happened to be female whereas the recipient was male. This point allowed the scientists to show, via a technique called fluorescence in situ hybridization, or FISH, that the recipient’s hematopoietic cells completely originated from the donor. FISH labels specific chromosomal sequences with easily detectable fluorescent dyes. Using different probes for sequences specific to the X- and Y chromosomes, the scientists saw that two X chromosomes and no Y chromosome existed in the patient’s population of peripheral blood mononuclear cells (PBMC). They were a bit surprised. The transplantation happened two decades ago – and still, the patient’s current PBMC population was entirely derived from his sister!
The scientists continued to show that sterile kiwi extract indeed caused a substantial increase in the proliferation of PBMCs from both donor and recipient, which was not observed in PBMC populations obtained from non-allergic control patients. Quod erat demonstrandum.
The now proven transfer of allergies via transplantation of hematopoietic stem cells opens up new considerations regarding such procedures. Screening potential donors for their allergic profile may be useful. Moreover, new approaches to severe allergic asthma or autoimmune diseases like Lupus, which can be aggravated by allergic reactions, may be envisioned. If a transfer of hematopoietic stem cells can cause allergic reactions, cellular therapy may also, conceivably, alleviate problematic allergies, if non-allergic donor cells are utilized.
At HemaCare, we are excited about such prospects and provide different populations of a wide variety of human cells, including hematopoietic stem cells. We offer bone marrow-derived cells such as CD133+, CD34+ or mesenchymal stem cells as well as mononuclear cells and unprocessed bone marrow from healthy volunteers, pre-screened for a variety of diseases. If any of these could further your research, please call us at (877) 397-3087 to discuss your needs.
 Ip W, Cale C, Veys P, Qasim W. Peanut allergy transferred by BMT. Bone Marrow Transplant 2014; 49: 993–994.
 Garzorz N, Thomas J2Eberlein B, Haferlach C, Ring J, Biedermann T, et al. Newly acquired kiwi fruit allergy after bone marrow transplantation from a kiwi-allergic donor. J Eur Acad Dermatol Venereol. 2016 Mar 16. doi: 10.1111/jdv.13617