Alloreactive Regulatory T Cells Allow the Generation of Mixed Chimerism and Transplant Tolerance.

Front Immunol

Departmento de Biología, Facultad de Ciencias, Universidad de Chile , Santiago , Chile.

Published: December 2015

The induction of donor-specific transplant tolerance is one of the main goals of modern immunology. Establishment of a mixed chimerism state in the transplant recipient has proven to be a suitable strategy for the induction of long-term allograft tolerance; however, current experimental recipient preconditioning protocols have many side effects, and are not feasible for use in future therapies. In order to improve the current mixed chimerism induction protocols, we developed a non-myeloablative bone-marrow transplant (NM-BMT) protocol using retinoic acid (RA)-induced alloantigen-specific Tregs, clinically available immunosuppressive drugs, and lower doses of irradiation. We demonstrate that RA-induced alloantigen-specific Tregs in addition to a NM-BMT protocol generates stable mixed chimerism and induces tolerance to allogeneic secondary skin allografts in mice. Therefore, the establishment of mixed chimerism through the use of donor-specific Tregs rather than non-specific immunosuppression could have a potential use in organ transplantation.

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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4655502PMC
http://dx.doi.org/10.3389/fimmu.2015.00596DOI Listing

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