An Excellent Step on the Journey Towards Less Barbaric Bone Marrow Transplants
Even after much progress since 1968, a bone marrow transplant remains a barbaric procedure in which the immune system is more or less destroyed using chemo and radiation (“conditioning” is the polite term for the barrage of chemo and/or radiation). The immune system is then rebuilt with transplanted stems cells.
Now, it appears some clever molecular researchers appear figured out an excellent step towards eliminating the radiation part of the bmt process. ScienceDaily has the story in a July 11, 2014 article. The full article is in Cell Stem Cell. The article is: Kadriye Nehir Cosgun, Susann Rahmig, Nicole Mende, Sören Reinke, Ilona Hauber, Carola Schäfer, Anke Petzold, Henry Weisbach, Gordon Heidkamp, Ariawan Purbojo, Robert Cesnjevar, Alexander Platz, Martin Bornhäuser, Marc Schmitz, Diana Dudziak, Joachim Hauber, Jörg Kirberg, Claudia Waskow. Kit Regulates HSC Engraftment across the Human-Mouse Species Barrier. Cell Stem Cell, 2014; DOI: 10.1016/j.stem.2014.06.001.
The press release and ScienceDaily explain the new finding, which is working in mice:
“The trick used by Claudia Waskow’s team to achieve optimal stem cell engraftment was the introduction of a naturally occurring mutation of the Kit receptor into mice that lack a functional immune system. This way they circumvented the two major obstacles of blood stem cell transplantation: the rejection by the recipient’s immune system and absence of free niche space for the incoming donor stem cells in the recipient’s bone marrow. Space is usually provided by irradiation therapy, called conditioning, because it damages and depletes the endogenous stem cells and thus frees space for the incoming human cells. However, irradiation is toxic to many cell types and can lead to strong side effects. The Kit mutation in the new mouse model impairs the recipient’s stem cell compartment in such a way that the endogenous blood stem cells can be easily replaced by human donor stem cells with a functional Kit receptor. This replacement works so efficiently that irradiation can be completely omitted allowing the study of human blood development in a physiological setting. The model can now be used to study diseases of the human blood and immune system or to test new treatment options.”