基于AdCTLA4-Ig的非清髓性方案在造血干细胞嵌合体诱导大鼠后肢移植免疫耐受中的应用

发布时间：2018-02-21 06:22

本文关键词： CTLA4-Ig重组腺病毒非清髓性嵌合体免疫耐受后肢移植物　出处：《第四军医大学》2008年硕士论文　论文类型：学位论文

【摘要】： 目的:探讨基于CTLA4-Ig重组腺病毒(AdCTLA4-Ig)的非清髓性方案在造血干细胞嵌合体诱导复合组织异体移植免疫耐受中的作用。方法:以近交系Brown Norway(RT1n)大鼠为供体,Lewis(RT11)大鼠为受体。实验分4组:A组:受体直接给予同种异体后肢移植,移植前不进行非清髓性预处理,移植后仅给予低剂量CsA(8 mg/kg/d)腹腔注射。B组:受体先给予非清髓性预处理,首先每天给予免疫抑制剂三联方案(腹腔注射RAPA+MMF+MP;days -33～100),然后分3次尾静脉注射AdCTLA4 -Ig(5×109 PFU/d,days -30,0,30),而后接受3Gy(照射率0.5Gy/min)低强度全身照射,不给予骨髓移植,全身照射后30d进行大鼠后肢移植(day 0)。C组:受体预处理方案同B组,在低强度全身照射后4h内尾静脉注射供体骨髓细胞(100×106,day -30),骨髓移植后30d进行大鼠后肢移植(day 0)。D组:受体预处理方案及骨髓移植方法同C组,但大鼠后肢移植供体为第三方动物WF大鼠(day 0)。在后肢移植后第100d各组均停止免疫抑制剂三联方案,仅给予低剂量CsA(8 mg/kg/d,days 100～),直至大鼠后肢移植物发生排斥反应而坏死。通过外周血嵌合率检测,GVHD检测,后肢移植物存活情况观察,移植物组织病理学检查与评价及混合淋巴细胞反应对免疫耐受状态进行分析评价。结果:C组外周血嵌合率为(38.8±10.6%,day 0)并长期保持稳定(29.3±11.9%,day 300),均未发生GVHD,停止免疫抑制剂三联方案后移植物存活天数200天(A组,B组、D组均发生免疫排斥,存活天数分别为8±2天,18±3天及20±2天,与C组相比较,p0.01)。C组移植物病理学检查显示无毛囊炎及血管周围炎等慢性免疫排斥现象,混合淋巴反应显示为供体特异性免疫耐受状态。结论:基于CTLA4-Ig重组腺病毒(AdCTLA4-Ig)的非清髓性骨髓移植方案可以诱导长期稳定的造血干细胞嵌合体状态,并可以诱导受体对大鼠后肢移植物的供体特异性部分性免疫耐受。
[Abstract]:Aim: to investigate the role of nonmyeloablative regimen based on CTLA4-Ig recombinant adenovirus AdCTLA4-Igin in the induction of allograft tolerance by hematopoietic stem cell chimerism. Methods: the inbred Brown Norwayl RT1n rat was used as the recipient of Lewis tachycardia RT11. The rats were divided into 4 groups: group A: the recipients were given allograft hind limb transplantation directly, and no non-myeloablative preconditioning was performed before transplantation. After transplantation, only low dose CsA(8 mg / kg / d was injected intraperitoneally. Group B was given non-myeloablative preconditioning. Three doses of immunosuppressant regimen (intraperitoneal injection of RAPA MMF MPP days -33) were given daily, followed by three caudal intravenous injections of AdCTLA4 -IgA 5 脳 109PFU / dd days -30g / d, followed by low-intensity whole-body irradiation of 3 Gy (0.5 Gy / min) without bone marrow transplantation. 30 days after the whole body irradiation, the rat hind limbs were transplanted into group C: the receptor preconditioning regimen was the same as that in group B. Donor bone marrow cells were injected into the tail vein within 4 hours after low intensity whole body irradiation. Group D received rat hind limb transplantation on 30 days after bone marrow transplantation: the receptor preconditioning regimen and the bone marrow transplantation method were the same as those in C group. However, the donor of hindlimb transplantation was WF rats. On the 100th day after hind limb transplantation, all groups stopped the triple regimen of immunosuppressive drugs. Only a low dose of CsA(8 mg / kg / d days was given until the rat hind limb graft developed rejection and necrosis, and the survival of the hind limb graft was observed by the peripheral blood chimerism rate and the survival rate of the hind limb graft. Graft histopathology and mixed lymphocyte reaction were used to evaluate the immune tolerance state. Results the chimeric rate of peripheral blood was 38.8 卤10.6 / day _ 0 in group C and kept stable for a long time (29.3 卤11.9day). No GVHD was found in all of them. The graft survived 200 days after stopping the triple regimen of immunosuppressant. All the patients in group A and group B developed immune rejection. The survival days were 8 卤2 days, 18 卤3 days and 20 卤2 days, respectively. Compared with group C, the grafts of group C showed no chronic immune rejection, such as folliculitis and perivascular inflammation, and mixed lymphoid reaction showed donor specific immune tolerance. Conclusion: Non-myeloablative bone marrow transplantation based on CTLA4-Ig recombinant adenovirus AdCTLA4-Igcan induce long-term stable hemopoietic stem cell chimeric status and donor specific partial tolerance to rat hind limb grafts.
【学位授予单位】：第四军医大学
【学位级别】：硕士
【学位授予年份】：2008
【分类号】：R392

【参考文献】