title: The road to transplant tolerance is paved with good dendritic cells.
abstract: After transplantation, recipient T cells can recognize donor antigens either by interacting with MHC class II on donor bone marrow-derived cells (direct allorecognition), or by recognizing allogeneic peptides bound to self-MHC class II molecules on recipient antigen presenting cells (indirect allorecognition). The activation of pro-inflammatory T cells via either of these pathways leads to allograft rejection, so the suppression of both of these pathways is needed to achieve transplantation tolerance. A study in this issue of the European Journal of Immunology [Eur. J. Immunol. 2013. 43: 734-746] shows that allogeneic dendritic cells (DCs) modified to either lack expression of CD80/86 or over-express indoleamine 2,3-dioxygenase (IDO) are able to inhibit direct and/or indirect alloresponses in vitro and in vivo in mice. Notably, both allorecognition pathways were suppressed by the coexpression of self- and allo-MHC molecules on semi-allogeneic DCs. This Commentary discusses the challenges and potential of using genetically-modified DCs to suppress alloreactivity in the context of transplant tolerance.
authors: Transplantation Research Center, Department of Surgery, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA. gbenichou@partners.org
authors: Gilles
authors: G
authors: Benichou
authors: Georges
authors: G
authors: Tocco
mesh_terms: D000818:Animals; D016039:Corneal Transplantation; D003713:Dendritic Cells / Q000276:immunology*; D005260:Female; D006084:Graft Rejection / Q000276:immunology*; D056747:Immunomodulation; D023001:Transplantation Tolerance / Q000276:immunology*