胰腺移植急性排斥反应中的细胞凋亡

目的　观察胰腺移植急性排斥反应中的细胞凋亡变化。方法　对封闭群大鼠作单纯胰腺移植 (A组 )和胰脾联合移植 (B组 ) ,手术后第 3、7、12、2 0天每组各处死 5只 ,切取移植胰 ,石蜡包埋切片 ,原位DNA缺口末端标记 (TUNEL)法测定胰腺组织细胞凋亡。结果　A组术后第 3、7、12、2 0天胰腺细胞凋亡数分别为 (15 2 .5 5± 2 7.2 4)、(5 0 8.19± 117.83)、(70 1.33± 130 .17)和 (10 10 .5 6±114.6 9)个 /高倍视野 ;B组分别为 (12 4.87± 19.11)、(198.6 8± 31.99)、(492 .2 5± 93.0 1)和(6 49.80± 140 .91)个 /高倍视野。 2组各时点均显著高于正常胰腺。第 7、12、2 0天A组也显著高于B组。结论　胰腺移植急性排斥时细胞凋亡活性明显增高。     

脾移植前去除成熟树突状细胞预防移植排斥反应的体外研究

目的 建立治疗性单抗溶液持续灌注大鼠脾脏模型,应用抗大鼠树突状细胞单克隆抗体（ＷＺＤ）降低大鼠移植脾的免疫原性。方法 以ＷＺＤ溶液持续灌注移植脾,筛选最佳方案并观察灌注后混合淋巴细胞培养（ｍｉｘｄｅ ｌｙｍｐｈｏｃｙｔｅ ｃｕｌｔｕｒｅ,ＭＬＣ）淋巴细胞增殖情况及脾细胞的超微结构,以及灌注后移植脾细胞的免疫组化情况。结果 ＷＺＤ灌注组ＭＬＣ淋巴细胞增殖能力明显降低,与对照组及应ＣｓＡ组相比差异有显     

PD142893诱导活化T细胞凋亡减轻大鼠肺移植急性排斥反应

T淋巴细胞在器官移植急性排斥反应中起核心作用，目前许多免疫抑制剂都是通过阻止T淋巴细胞的活化而发挥抗急性排斥效应的。本研究旨在探讨PD142893参与大鼠肺移植后对急性移植排斥反应的影响及对活化T细胞的作用。     

中药移植合剂对大鼠胰腺移植急性排斥反应的作用

目的:观察大鼠胰腺移植后的细胞凋亡情况,以及中药移植合剂在急性排斥反应中的作用并探讨其作用机制.方法:建立大鼠全胰十二指肠移植模型,均为异基因移植(以SD、Wistar大鼠作为供、受体),共分5组,每组10只.第1组:阴性对照组;第2组:环孢素A (cyclosporin A, CsA)组,5 mg/(Kg·d);第3组:中药移植合剂组,每100 g体重1 mL/d;第4组:中西医结合组,中药移植合剂每100 g体重1 mL/d CsA 2.5 mg/(Kg·d);第5组:亚治疗剂量CsA组,2.5 mg/(Kg·d).术后第7 d每组处死5只大鼠,取移植胰腺,受体肝脏、肾脏行病理学检查,应用原位末端标记法(TUNEL)检测细胞凋亡情况.余鼠待出现急性排斥反应时处死,观察各组移植胰腺有功能存活时间.结果:中药移植合剂可以延长移植胰腺有功能存活时间,抑制胰腺腺泡细胞凋亡,其与亚治疗剂量CsA合用后可以达到治疗剂量CsA的抗排斥反应效果.结论:中药移植合剂具有一定的抗大鼠胰腺移植急性排斥反应的作用,作用机制与其抑制移植胰腺腺泡细胞凋亡有关,且与CsA具有协同作用.     

腺泡细胞凋亡在大鼠胰腺移植急性排斥反应中的意义

目的：观察移植胰腺的腺泡细胞凋亡及其与急性排斥反应的关系。方法：选用SD和Wistar大鼠进行全胰十二指移植。实验分为同基因移植组（Wistar→Wistar）和异基因移植组（SD→Wistar）两组。于术后第3d、5d和7d分批处死受体，取移植胰腺标本用HE染色和原位末端标记（TUNEL）技术检测移植胰腺切片，进行排斥反应的病理学评分和计数凋亡指数（AI）。结果：发生凋亡的细胞主要是腺泡细胞，同基因移植组胰腺有散在的腺泡细胞凋亡，AI在术后无明显变化。异基因移植组胰腺腺泡细胞凋亡在术后第3d、5d和7d逐渐升高，AI与急性排斥反应的病理学评分成正相关。结论：细胞凋亡与移植胰腺急性排斥反应的严重程度显著相关，凋亡指数可作为判断移植物损伤程度的指标，对急性排斥反应的诊断有一定的参考价值。     

细胞凋亡在大鼠胰腺移植急性排斥反应中的作用

目的探讨细胞凋亡和相关因子Fas、FasL、bcl-2和bax在大鼠胰腺移植急性排斥反应中的作用,评价十二指肠黏膜活检在胰腺移植中诊断排斥反应的价值。方法选SD和Wistar大鼠行全胰十二指肠移植,实验分同基因胰腺移植组和异基因胰腺移植组。于移植术后第3、5及7d分批处死受体,取移植胰腺和十二指肠标本用HE染色和原位末端脱氧核糖核苷酸转移酶标记技术(TUNEL)检测移植物。免疫组化法检测移植后胰腺和十二指肠Fas、FasL、bcl-2和bax的表达。结果异基因胰腺移植组胰腺和十二指肠病理评分相同者占61.1%(11/18);评分不同者占38.9%(7/18),其中胰腺评分较高者6例,十二指肠黏膜评分较高者仅1例。异基因胰腺移植组胰腺和十二指肠病理学评分和细胞凋亡指数均明显高于同基因胰腺移植组(P<0.05,P<0.01)。胰腺和十二指肠细胞凋亡指数与急性排斥反应的病理学评分成正相关(r=0.965,P<0.01;r=0.942,P<0.01)。随着术后时间延长,排斥反应分级上升,细胞凋亡增加,FasL表达升高,在异基因移植组bcl-2表达下降,而Fas和bax表达无明显变化。结论细胞凋亡与移植胰腺急性排斥反应的严重程度呈正相关,细胞凋亡指数可作为判断移植物损伤程度的指标。FasL和bcl-2与胰腺移植急性排斥及组织损伤密切相关。十二指肠黏膜活检有助于判断有无胰腺急性排斥反应发生。     

胰腺腺泡细胞凋亡和Fas/Fas配体表达在大鼠胰腺移植急性排斥反应中的作用

目的探讨大鼠胰腺移植后细胞凋亡的变化、Fas/Fas配体(FasL)的表达及其与急性排斥反应的关系。方法实验分为同基因移植组和异基因移植组。分别于术后第3、5、7天处死受体,取移植胰腺,应用原位末端标记法(TUNEL)检测细胞凋亡,计算凋亡指数(AI),应用免疫组织化学及Westernblot检测Fas/FasL的表达。结果细胞凋亡主要发生在胰腺腺泡细胞,同基因移植组有散在的腺泡细胞凋亡,AI在术后无明显变化,Fas/FasL表达阴性;异基因移植组在术后第3、5、7天胰腺腺泡细胞凋亡发生率逐渐增加(28.40±3.75,39.40±5.59,57.30±8.53,P<0.01),Fas/FasL表达逐渐增强,AI与急性排斥反应程度呈显著正相关(rs=0.932,P<0.01)。结论胰腺腺泡细胞凋亡和Fas/FasL表达在胰腺移植急性排斥反应中发挥重要作用,凋亡指数对胰腺移植急性排斥反应的诊断有一定的参考价值。     

小肠移植排斥反应期移植肠粘膜细胞凋亡的研究

目的 明确移植肠上皮细胞凋亡在小肠移植排斥反应中的意义及诊断价值。方法 选用近交系大鼠Ｆ３４４／Ｎ和Ｗｉｓｔａｒ／Ａ进行全小肠异位移植,实验分４组。第１组：非基本对照 ;第２组;同基因移植组;第３组;异基因移植组;第４组;异基因移植加环孢霉素Ａ治疗组。术的第３、５、７天取移植肠进行病理学检查,采用ＴｄＴ介导的脱氧核苷酸原位末端标记法（ＴＵＮＥＬ）检测移植肠上皮细胞凋亡。结果 病理学检查显示第３组大     

大鼠小肠移植排斥反应中细胞凋亡的动态研究

目的 研究小肠移植后排斥反应与细胞闻过则喜良心的关系以及雷帕霉素（RAPA）对移植后排斥及细胞凋亡的作用。方法 以SD大鼠为假移植组作对照（1组）,其他各组采用Wistar→SD大鼠异位小肠移植模型,移植后随机分为排斥反应组（2组）、雷帕霉素2mg.kg^-1组（3组）和雷帕霉素4mg.kg^-1.d^-1组（4组）,每组术后1、3、5、7d分别处死6只大鼠,获取移植肠组织行病理学检查和细胞凋亡检测。结果 各组在术后1、3d均未发现排斥反应,2组术后5、7d分别出现I度和Ⅱ度排斥,3组仅在术后7d出现早期排斥迹象,4组枯术后一直未见排斥证据,小肠细胞凋亡数量在排斥反应前期和排斥反应时显著增加,不同强度的排斥反应,细胞凋亡数量差异有显著性。结论 排斥反应中可出现大量的肠细胞凋亡,其始发时间早于排斥的组织学发现,凋亡细胞数量与排斥强度呈正相关,可作为小肠移植后排斥反应的另一种可信的标志物。雷帕霉素对排斥反应的抑制能力与剂量有关,并不能抑制肠细胞凋亡的发生。     

异种移植超急性排斥反应的研究进展

异种移植排斥反应一般分为超急性排斥（xenogeneic hyperacute rejection，HAR），延迟性排斥（又称急性血管性排斥），急性细胞性排斥和慢性排斥。     

Opposite effects of donor apoptotic versus necrotic splenocytes on splenic allograft tolerance

BACKGROUND: Apoptotic cells have immunosuppressive activity, whereas necrotic cells activate immune response, indicating they might have different effects on immune rejection against splenic allografts. The aim of this study was to determine whether administration of apoptotic or necrotic splenocytes of donor origin could impact the acute rejection of splenic allografts. MATERIALS AND METHODS: Apoptotic or necrotic splenocytes derived from donor rats were induced by irradiation or freeze thaw, respectively. Heterotopic vascularized spleen transplantation was performed from Wistar-Furth (donor) to Sprague-Dawley (recipient) rats, and splenocytes were intravenously injected into the recipients. At different time points, the recipients were sacrificed and the splenic allografts underwent histological examination. The interferon-gamma (IFN-gamma) and transforming growth factor-beta1 (TGF-beta1) in sera, spleens of recipients, and donor splenocytes before administration were measured. Mixed leukocyte reaction (MLR) was detected with recipient splenocytes as effectors and donor splenocytes as stimulators. RESULTS: Exposure to gamma-irradiation at dose of 10,000 rad caused over 80% splenocytes to become apoptotic. The levels of TGF-beta1 released by apoptotic splenocytes in vitro were significantly higher than that by untreated splenocytes, whereas there was almost no TGF-beta1 detected in necrotic splenocytes culture medium. Administration of apoptotic splenocytes significantly attenuated acute rejection of splenic allografts, evidenced by less severe splenic histological alteration and reduction of histological scores compared with control; whereas necrotic splenocytes exacerbated the acute rejection. Apoptotic splenocytes inhibited production of IFN-gamma but increased the levels of TGF-beta1, whereas necrotic splenocytes showed opposite activity in production of those cytokines. Administration of apoptotic splenocytes inhibited MLR, and necrotic splenocytes promoted MLR. CONCLUSIONS: The apoptotic and necrotic splenocytes exhibited opposite effects on acute rejection against splenic allografts, and IFN-gamma and TGF-beta1 have been involved in the effects.     

Association of inclusion of the donor spleen in pancreaticoduodenal transplantation with rejection

Clinical pancreas transplantation (txp) using a pancreaticoduodenal allograft (pda) and the donor spleen has been applied as treatment for insulin-dependent diabetes mellitus. Inclusion of the spleen in the pda is purported to protect against thrombosis and may be of possible immunological benefit. In pancreatectomized pigs, we compared the results of pda txp with (n = 8) and without (n = 10) the donor spleen. Animals were maintained on cyclosporine (6 mg/kg/day i.v.) and prednisolone (1.5 mg/kg/day i.v. tapered over 7 days to a maintenance dose of 0.5 mg/kg/day i.v.). Pancreatic exocrine enzyme replacement was administered daily. In 10 recipients of the technically successful pda without the spleen, rejection (blood glucose greater than 150 mg/dl) was not seen in the 28 days after txp. Mean daily blood glucose was 95 +/- 8 mg/dl during this period. In contrast, 5 of 8 recipients of the technically successful pda with the donor spleen rejected their grafts an average of 13 days (range 7-16) after txp (P less than 0.01). Mean daily blood glucose was 88 +/- 21 mg/dl prior to the declaration of rejection and increased to 275 +/- 59 mg/dl after rejection (P less than 0.0001). Rejection was histologically confirmed in all cases. None of the recipients of the pda with the donor spleen developed signs of graft-versus-host disease. Glucose tolerance testing carried out 28 days after transplantation in normoglycemic pigs from both experimental groups demonstrated no difference between the groups. In the porcine pda model used in this study, the inclusion of the spleen in the pda was associated with rejection of the transplant.     

预输注供者凋亡的脾细胞诱导大鼠肝移植免疫耐受的研究

目的探讨肝移植预输注地塞米松体内诱导凋亡的供体脾细胞诱导受体肝移植免疫耐受可能性。方法实验分5组,对照组,单纯供体地塞米松处理组,单纯输供者脾细胞组,地塞米松诱导供者凋亡脾细胞输注组,第三品系组。每组均做Wistar至SD的肝移植,每组各10只Wistar、SD大鼠。用地塞米松3mg/(kg·d)处理Wistar大鼠3d后,第4天取供体的脾细胞输注受体,第10天行大鼠肝移植。观察术后第7天肝功能(ALT、TBil)的变化、病理改变和受体生存期。结果肝移植预输注凋亡细胞组的ALT、TBil较其它各组显著低(P<0·05);生存期明显长(P<0·05),病理改变较轻。结论肝移植预输注地塞米松体内诱导供体凋亡的脾细胞能诱导受体大鼠对移植肝的免疫耐受。     

Risk factors for acute rejection in living donor liver transplantation

The influence of human leukocyte antigen (HLA) compatibility and lymphocytotoxic crossmatch on acute rejection in living donor liver transplantation (LDLT) has not been well examined. We analyzed 100 consecutive adult LDLT cases. The patient and graft survival rates and post-operative complications were assessed. The relation between the incidence of acute rejection and some clinical factors including HLA and lymphocytotoxic matching was also examined. Patients with HLA DR zero mismatching (p = 0.02) or negative T-lymphocytotoxic crossmatch (p = 0.04) had a significantly lower chance of rejection within 6 wk after LDLT. However the results had no influence on the patient survival. Our results demonstrate that in LDLT, a graft from an HLA-DR zero mismatching or negative T-lymphocytotoxic crossmatch might be advantageous because of the decreased probability of early acute rejection.     

Early versus late acute rejection episodes in renal transplantation

BACKGROUND: Acute rejection is a major complication after renal transplantation and the most important risk factor for chronic rejection. We investigated whether the timing of the last treated acute rejection episode (ARE) influences long-term outcome and compared the risk profiles of early versus late ARE. METHODS: A cohort of 654 patients who underwent cadaveric renal transplants (1983-1997) that functioned for more than 6 months was studied. In 384 of 654 transplant recipients, one or more treated AREs were documented; the last ARE occurred in 297 of 384 transplant recipients within 3 months and in 87 of 384 after 3 months. Applying multivariate logistic regression analysis, we compared the predictor variables of the two groups with transplants without AREs. RESULTS: Ten-year graft survival rates censored for causes of graft loss other than chronic rejection were 94%, 86%, and 45% for patients without ARE, with early ARE, and with late ARE, respectively. Delayed graft function, odds ratio (OR) 2.37 (1.55-3.62), and major histocompatibility complex (MHC) class II incompatibility, OR 2.28 (1.62-3.20) per human leukocyte antigen (HLA)-DR mismatch, were independent risk factors for early ARE. In contrast, recipient age, OR 0.75 (0.61-0.93) per 10-year increase, donor age, OR 1.28 (1.07-1.53) per 10-year increase, female donor gender, OR 1.74 (1.03-2.94), and MHC class I incompatibility, OR 1.35 (1.07-1.72) per mismatch of cross reactive groups, were associated with late ARE. CONCLUSIONS: Late ARE has a detrimental impact on long-term graft survival and is associated with MHC class I incompatibility, whereas early ARE is correlated with HLA-DR mismatches and has a better prognosis. These data are consistent with the role of direct and indirect allorecognition in the pathophysiology of early and late ARE, respectively.     

脾脏在小鼠同种肝移植排斥反应中的作用

目的 观察脾切除在小鼠同种肝移植急性排斥反应过程中的作用.方法 双袖套法建立小鼠原位肝移植模型,随机分为3组,即建模保留脾脏组、建模3 d后切除脾脏与建模同时切除脾脏组,各组于移植术后14 d处死,ELESA法测定血清IgM水平;肝功能检测采用速率法;流式细胞仪检测CD4与CD8T细胞亚群;并同时行肝脏及脾脏的病理形态观察.结果 建模保留脾脏组、建模3 d后切除脾脏与建模同时切除脾脏组血清IgM水平分别为3.0181±0.4627、3.0936±0.4559、3.1953±0.4449,各组间差异无统计学意义(P＞0.05);ALT水平分别为108.6875±20.3657、83.0000±22.7799、76.8000±19.5784,差异有统计学意义(P＜0.05);AST水平分别为:105.3750±29.0583、93.0000±22.7799、93.2000±33.4220,各组间差异无统计学意义(P＞0.05);CD46+/CD8+T细胞分别为:1.9162±0.2778、1.5654±0.4750、1.4616±0.2762,差异有统计学意义(P＞0.05);3组肝脏间质及汇管区淋巴细胞浸润程度依次减弱,供肝灶状坏死程度逐渐减轻,在保留脾脏组中建模后第14天脾脏边缘区及淋巴鞘较建模同时切除的脾脏增宽.结论 在小鼠同种异体肝移植排斥反应中细胞免疫起主要作用,脾切除可部分抑制同种异体肝移植急性排斥反应,保护供体肝脏.     

骨化三醇在抑制大鼠同种肢体移植排斥反应中的作用

目的 探讨应用骨化三醇(1,25-二羟维生素D;简称:VD5)在抑制肢体移植排斥反应中的作用.方法 以Wistar大鼠为供者,SD大鼠为受者,建立同种肢体移植模型.随机将受者分为4组,每组12只.(1)对照组:术后不用免疫抑制剂,仅以15 ml·kg-1·d-1.生理盐水灌服.(2)他克莫司(FK506)组:将FK506用生理盐水稀释为0.5 mg/ml,术后前2周的用量为1.0 mg·kg-1·d-1,术后第3周起,每周灌服2次.(3)VD3组:将骨化三醇用生理盐水稀释为0.125 μg/ml,术后用量为2.5μg·kg-1·d-1,连续灌服4周.(4)VD3+FK506组:术后联合应用骨化三醇及FK506,用药方法和用量与FK506组和VD3组相同.术后观察各组受者移植肢体排斥反应发生的时间和存活时间;流式细胞仪检测T淋巴细胞亚群CD4+、CD8+细胞的百分率.结果 对照组、FK506组、VD3组以及VD3+FK506组肢体移植后排斥反应发生的时间分别为:(3.50±0.50)d、(13.13±1.50)d、(10.63±0.38)d和(29.25±0.63)d;移植肢体的存活时间分别为:(8.50±0.50)d、(26.25±1.50)d、(17.25±0.38)d和(62.00±0.63)d;与对照组比较,VD3组排斥反应发生的时间和移植肢体的存活时间均明显延长,差异有统计学意义(P＜0.01);VD3+FK506组抗排斥反应效果更佳,与FK506组和VD3组比较,差异有统计学意义(P＜0.01).VD3组T淋巴细胞亚群CD4+/CD8+细胞的比值明显低于对照组,VD3+FK506组又明显低于VD3组和FK506组(P＜0.01).结论 骨化三醇能明显减轻同种肢体移植排斥反应,延长移植肢体的存活时间;骨化三醇与FK506联合应用效果更佳,二者具有协同作用.     

同种异基因大鼠心脏移植急性排斥反应的相关基因分析

目的运用基因芯片技术分析同种异基因大鼠心脏移植后急性排斥反应的基因表达谱。方法建立同种异基因大鼠颈部心脏移植模型,并设同种同基因大鼠颈部心脏移植作为对照。术后5d,两组移植心脏中抽提总RNA,纯化后的mRNA进行逆转录制备杂交探针,应用含有4096个靶基因的表达谱芯片对两组移植心脏组织进行差异表达谱分析。结果两组之间杂交信号有明显差异,同种异基因心脏移植术后差异表达基因共有210条(下调96条,上调114条),其中已知基因有33条(下调13条,上调20条),未知基因177条(下调83条,上调94条);已知基因中有15条(上调2条,下调13条)尚未见报道。结论运用基因芯片技术分析同种异基因心脏移植术后急性排斥相关基因,可为进一步研究其发病机理和为治疗提供新思路。