| ObjectiveTo establish durable and stable mixed chimeras and explore its effect on prevention and cure of acute graft-versus-host disease after xenogeneic bone marrow transplantation.Methods1 .Establishing durable and stable mixed chimeras(MC) model: SD rats were conditioned with sublethal total body irradiation(TBI), following by infusion of bone marrow cells(BMCs) of BALB/c mice within 4h, then were intraperitonially administered cyclophosphamide(Cy) 2 days later, so the MC model were established. Afterwards recipient rats were randomly parted as two groups: Al group was that recipient rats were infused by sterile sodium chloride solution on day 14, 21, 28 after xenogeneic bone marrow transplantation (XBMT) as comparison; Bl group was that recipient rats were infused by donor spleen cells (SCs) of different dosage on day 14, 21, 28 after XBMT. Tolerance status of the recipient rats induced and maintained were tested by mice lymphoid chimerism, skin grafting and mixed lymphocyte reaction (MLR).2. Effect of durable and stable MC on acute graft-versus-host disease (aGVHD) after XBMT: After establishing durable and stable MC in above-mentioned model, BALB/c and C57BL/6 mice were treated with lethal TBI, afterwards the mice were randomly parted as four groups: A2 group was that BALB/c mice were infused inversely by BMCs and SCs of chimeras rats in Al group. B2 group was that BALB/c mice were infused inversely by BMCs and SCs of chimeras rats in Bl group. C2 group was that C57BL/6 mice were infused by BMCs and SCs of chimeras rats in Bl group. D2 group was that BALB/c mice and C57BL/6 mice were infused bysterile sodium chloride solution. The symptom and sign, histopathological examination and survival time of transplanted mice in every group were observed. Engraft status of rat cells were tested in agonal mice of A2 group and survival mice of B2 group, then change of chimeras in B2 group were traced.Results1. The mice lymphoid chimerism in the peripheral blood lymphocyte of the SD rats: after SD rats were treated by sublethal TBI, infusion of BALB/c mice BMCs, injection of Cy intraperitonially and donor lymphocyte infusion (DLI), the peripheral blood lymphocyte of the SD rats in every group were treated by fluorescent monoclonal antibody immunity histochemistry in FCM. On 60 day the value was 3.98%~10.07% in Al group, 14.31%~21.94% in Bl group. On 120 day the value descend to 0.58%~3.34% in Al group, but the value in Bl group can be maintained 14.11%~24.38%.2. The survival of skin graft: skin grafting were administered on 45 day after infusion of SCs. The survival time of skin graft in Bl group rat to BALB/c mice skin was longer than that in Al group rat to BALB/c mice, there were different remarkably between the two group. The survival time of skin graft in Bl group rat to C57BL/6 mice skin was curtate evidently, and there was different significantly between that of skin graft in Bl group rat to C57BL/6 mice and in Bl group rat to BALB/c mice.3. The result of MLR: MLR assays of two groups to specific donor and Bl group rat to irrespective third-party were performed on 90 day and 120 day after infusion of SCs. On 90 day the reaction of two groups to specific donor was mild, the difference was not significant. On 120 day the reaction of Al group to specific donor was violent, but the reaction of Bl group to specific donor was still mild, there were different significantly between two group. The reaction of Bl group to irrespective donor was always violent-6-obviously.4. The symptom and sign of aGVHD: BALB/c and C57BL/6 mice radiated lethally were infused by the BMCs and SCs of above-mentioned chimeras rat proportionally, so aGVHD model were established. It shows that inversely transplanted mice in A2 group and C2 group represent less meal, less movement, energy cachexia, diarrhea, lordotic, lackluster hair, lose weight, skin tetter, skin canker and so on within 15 day. The transplanted mice in B2 group represent above-mentioned symptom and sign from 24th to 26th day, a... |
