215. Vascularized bone marrow transplantation extends survival of vascularized skin allografts

Abstract

Purpose Vascularized bone marrow allotransplantation is known to be the most effective way of multilineage chimerism induction in the experimental and clinical models. In this study, we introduce combined vascularized skin/vascularized bone transplantation model (VS/VB) to evaluate the effect of the VB transplantation on tolerance induction across strong MHC barrier, under αβ-TCRmAb+CsA treatment protocol. Methods Thirty-six-transplantations between ACI (RT1a) donors to Lewis (RT1I) recipients were performed in three experimental groups of six animals each. In isograft control group and allograft rejection control group no treatment was applied. The experimental group III of vascularized skin/vascularized bone allograft TCR/CsA for 7 days only. The efficacy of (VS/BM) was treated with ab immunosuppressive treatment and the level of chimerism in the peripheral blood of recipients were determined by flow cytometry (FC). Standard H+E technique was applied for the evaluation of the grade of graft rejection. Results The Isograft Control Group I transplants survived indefinitely. In allograft rejection control transplants were rejected between 5 and 9 days post-transplant. The survival time was significantly (p Conclusion Transplantation of the vascularized skin with vascularized bone resulted in significant prolongation of the allograft survival. Allotransplantation of the vascularized bone with marrow natural micro-anatomic environment increases of the donor-derived stem and progenitor cells engraftment resulted in the establishment of the stable, donor specific chimerism.