This includes elbow, arm, hand and face transplantations and requires surgical skill and a multidisciplinary approach. Because in these cases transplanted tissues are always coming from a genetically non-identical donor (allograft), they generate a rejection process mediated by the recipient immune system.
Therefore, chronic immunosuppression is required to prevent rejection and graft loss, with some side effects that may limit the indication of transplantation based on logic of cost-benefit ratio. The ideal solution would be to get reliable protocols for inducing transplantation tolerance.
Very recently, funded by the Melina Nakos foundation and the First Elite program of the Walloon region, and in collaboration with Professor Frédéric Schuind from Erasme hospital, doctors Zanzhuo Li and Alain Le Moine, at the Institute for Medical Immunology – Université libre de Bruxelles (ULB), developed a mouse model of composite tissue allograft including a vascularised femur.
The results of their research are published in the American Journal of Transplantation, the official journal of the American Society of Transplantation (AST).
In this model, a short course of immunosuppression at the time of transplantation allowed to make recipients robustly tolerant to the transplant. Importantly, tolerance was donor-specific, since recipients were still able to reject a third party allograft (unrelated to the donor), meaning that recipient immune system ultimately recovered responsiveness. It was shown that donor-type haematopoietic stem cells derived from the transplanted bone repopulated the recipient immune system and induced tolerance by removing anti-donor cells. This did not require recipient aggressive preconditioning which is considered as a too risky treatment to be applied in the context of composite tissue allografts. Therefore, vascularized bone transplantation containing donor-derived bone marrow cells might become a valuable tool for inducing transplantation tolerance in composite tissue allografts but also in other transplantations.
This study demonstrates the feasibility of stem cells grafts through a vascularised bone and the tolerance that it induces in the recipient of a composite tissue allograft.
In terms of clinical applications, this could be an alternative method to the intravenous injection of stem cells which does not induce a stable chimerism in the recipient unless after a heavy conditioning of the patient.
Zhanzhuo L, Benghiat FS, Kubjak C, Noval Rivas M, Cobbold S, Waldmann H, Petein M, Schuind F, Goldman M, Le Moine A. CD8+ T cell depletion and rapamycin synergize with signal 1 and 2 blockade to induce robust limb allograft tolerance in mice. Am J Transplant 2008 ; 8 : 1-10.For scientific informations :
Nancy Dath | alfa
A whole-body approach to understanding chemosensory cells
13.12.2017 | Tokyo Institute of Technology
Research reveals how diabetes in pregnancy affects baby's heart
13.12.2017 | University of California - Los Angeles Health Sciences
MPQ scientists achieve long storage times for photonic quantum bits which break the lower bound for direct teleportation in a global quantum network.
Concerning the development of quantum memories for the realization of global quantum networks, scientists of the Quantum Dynamics Division led by Professor...
Researchers have developed a water cloaking concept based on electromagnetic forces that could eliminate an object's wake, greatly reducing its drag while...
Tiny pores at a cell's entryway act as miniature bouncers, letting in some electrically charged atoms--ions--but blocking others. Operating as exquisitely sensitive filters, these "ion channels" play a critical role in biological functions such as muscle contraction and the firing of brain cells.
To rapidly transport the right ions through the cell membrane, the tiny channels rely on a complex interplay between the ions and surrounding molecules,...
The miniaturization of the current technology of storage media is hindered by fundamental limits of quantum mechanics. A new approach consists in using so-called spin-crossover molecules as the smallest possible storage unit. Similar to normal hard drives, these special molecules can save information via their magnetic state. A research team from Kiel University has now managed to successfully place a new class of spin-crossover molecules onto a surface and to improve the molecule’s storage capacity. The storage density of conventional hard drives could therefore theoretically be increased by more than one hundred fold. The study has been published in the scientific journal Nano Letters.
Over the past few years, the building blocks of storage media have gotten ever smaller. But further miniaturization of the current technology is hindered by...
With innovative experiments, researchers at the Helmholtz-Zentrums Geesthacht and the Technical University Hamburg unravel why tiny metallic structures are extremely strong
Light-weight and simultaneously strong – porous metallic nanomaterials promise interesting applications as, for instance, for future aeroplanes with enhanced...
11.12.2017 | Event News
08.12.2017 | Event News
07.12.2017 | Event News
13.12.2017 | Health and Medicine
13.12.2017 | Physics and Astronomy
13.12.2017 | Life Sciences