A vascularized bone marrow transplantation model in rat

Abstract

Objective To establish a simple and reliable vascularized bone marrow transplantation (VBMT) model as a new method for bone marrow transplantation.Methods The femoral bones were transplanted into the recipient inguinal regions and their nutrient vessels were anastomosed with recipients vessels.Twenty Lewis rats were divided into 3 groups.In syngeneic group,femoral bone transplantation was performed between Lewis rats.In both rejection and immunosuppression groups,BN rats were used as donors and Lewis rats as recipients.Rats in rejection group received no treatment,and those in immunosuppression group were given cyclosporine A after allotransplantation.The viability of the all grafts was evaluated grossly and morphologically,and the chimerism was determined by using flow cytometry.Results The bone grafts in syngeneic group remained viable and the bone marrow maintained normal morphologically at 30th day post-transplant,but the grafts in rejection group were clearly rejected at 7th day after transplantation,and the number of bone marrow cells was decreased sharply with almost no chimerism.In accord with syngeneic grafts,the grafts in immunosuppression group showed normal appearance of the viable tissue.Donor-specific chimerism was confirmed in peripheral blood at 1st,2nd,3rd,and 4th week posttransplant,and the chimerism level was detected at (4.7 ± 2.0) ％,(2.2 ± 1.2) ％,(1.8 ± 0.9) ％ and (1.5 ± 0.3) ％ respectively.Conclusion Vascularized femoral bone grafting is a simple and reliable method for the transplantation of bone marrow,and may provide a useful tool for the study of immune tolerance. Key words: Vascularized bone marrow transplantation; Chimerism; Immune tolerance; Femoral bone transplantion