胸腺内注射异基因抗原诱导特异性神经移植耐受的实验

背景:主要组织相容性复合物抗原不匹配是发生移植排斥的主要原因,诱导免疫耐受是防止器官移植排斥的理想途径,在胸腺内通过阴性选择可获得对自身耐受的T细胞,胸腺内异基因抗原注射是否可获得对该抗原的免疫耐受?目的:观察胸腺内注射异基因抗原在同种异基因神经移植免疫耐受中的作用。设计:对照观察实验。单位:哈尔滨医科大学免疫学教研室,哈尔滨医科大学第四临床医院骨科。材料:供体鼠C57BL/6(H-2b)30只,雄性,6～8周龄,体质量18～22g,由黑龙江省兽医研究所提供;受体鼠Balb/c(H-2d)60只,雌性,6～8周龄,体质量18～22g,由北京实验动物中心提供。主要组织相容性复合物(H-2b)抗原由哈尔滨医科大学免疫教研室制备,蛋白浓度为4.4g/L。方法:实验于2002-06/11在哈尔滨医科大学免疫教研室完成。将受体鼠Balb/c随机分为4组:胸腺内注射组、同系同基因移植组、异体神经移植组、免疫抑制剂组。自供体鼠C57BL/6(H-2b)的脾细胞中提取MHC抗原,注入受体鼠Balb/c(H-2d)胸腺内,两周后移植供体坐骨神经。移植后3周做单向混合淋巴细胞培养,诱导迟发型超敏反应。主要观察指标:各组混合淋巴细胞反应、诱导迟发型超敏反应的差异。结果:纳入供体鼠C57BL/6(H-2b)30只和受体鼠Balb/c(H-2d)60只,全部进入结果分析。①混合淋巴细胞反应结果:同系同基因移植组、胸腺内注射组和免疫抑制剂组细胞增殖均明显低于异体神经移植组[(546.1±75.1),(2668.3±533.8),(3101.3±429.1),(4312.3±534.1)min-1,P<0.05]。②诱导迟发型超敏反应结果:同系同基因移植组、胸腺内注射组和免疫抑制剂组两侧足垫的厚度差均明显低于异体神经移植组[(41.1±3.7),(72.1±5.1),(57.6±11.3),(86.2±13.2)μm,P<0.05]。结论:胸腺内注射异基因H-2b抗原可以诱导特异性神经移植耐受。

Inhibition of nerve transplantation rejection in adult mice induced by intrathymic injection of allogeneic antigen

BACKGROUND: Uncoupling of major histocompatibility complex (MHC) is the main cause for transplantation rejection, and it is the best way to prevent transplantation rejection by induce immunological tolerance of the recipient to the donor organ. Self-tolerant T cells can be obtained by negative selection in thymus, whether the intrathymic injection of allogenic antigen can get the immunological tolerance to the antigen?OBJECTIVE: To observe the effects of intrathymic injection of allogenic antigen on inducing immunological tolerance in nerve transplantation.DESIGN: A comparative observation.SETTINGS: Department of Immunology, Harbin Medical University; Department of Orthopaedics, Fourth Clinical Hospital of Harbin Medical University.MATERIALS: Thirty donor C57BL/6 mice (H-2b), male, aged from 6-8 weeks, weighing 18-22 g, were purchased from the Veterinarian Institute of Heilongjiang Province; While 60 recipient Balb/c mice (H-2b) female, aged from 6-8 weeks, weighing 18-22 g, from Beijing Experimental Animal Center. MHC (H-2b) antigen was prepared by the Department of Immunology, Harbin Medical University, and the concentration of protein was 4.4 g/L.METHODS: The experiments were carried out in the Department of Immunology, Harbin Medical University from June to November 2002. The recipient Balb/c mice were randomly divided into four groups: intrathymic injection group, syngenic transplantation group, allogenic transplantation group and immunosuppressant drug group. MHC (H-2b) antigen was extracted from splenic cells of donor C57BL/6 mice and injected intrathymically into recipient Balb/c mice (H-2d). Two weeks later, the sciatic nerve was transplanted to the recipient mice. Mixed lymphocyte reaction and delayed-type hypersensitivity (DTH) were detected at 3 weeks after transplantation.MAIN OUTCOME MEASURES:The differences of mixed lymphocyte reaction and DTH were compared among the groups.RESULTS: All the 30 donor C25BL/6 mice (H-2b) and 60 recipient Balb/c mice (H-2d) were involved in the analysis of results.①Results of mixed lymphocyte reaction: The cell proliferations in the syngenic transplantation group and intrathymic injection group were obviously lower than that in the allogenic transplantation group [(546.1±75.1), (2 668.3±533.8), (3 101.3±429.1), (4 312.3±534.1) minutes-1, P＜0.05].②Results of DTH: The thicknesses difference between two pads in the syngenic transplantation group and intrathymic injection group were obviously lower than that in the allogenic transplantation group [(41.1±3.7), (72.1±5.1), (57.6±11.3), (86.2±13.2)μm, P＜0.05].CONCLUSION:The intrathymic injection of donor H-2b antigen could induce immunological tolerance of nerve transplantation.