他克莫司对脂肪肝供体大鼠肝移植围手术期移植物功能保护作用的研究

目的探讨他克莫司对脂肪肝供体大鼠肝移植围手术期移植物功能的保护作用及机制。方法建立脂肪肝供体Wistar大鼠肝移植模型,实验组与对照组受体大鼠分别在术中、术后注射他克莫司(0.3mg/kg)或生理盐水,在移植物再灌注0h、24h、72h和1周后分别检测两组受体大鼠的血清肝酶[丙氨酸氨基转移酶(ALT)、天冬氨酸氨基转移酶(AST)、乳酸脱氢酶(LDH)]、内皮素(ET)和脂质过氧化指标[超氧化物歧化酶(SOD)、过氧化氢酶(CAT)和丙二醛(MDA)],同时取肝组织制成匀浆检测其SOD、CAT和MDA水平,取小块肝组织制成切片在电镜下观察肝脏超微结构,采用原位末端标志法(TUNEL)检测肝组织的细胞凋亡情况。结果实验组大鼠的血清ALT、AST、LDH、ET和MDA水平明显低于对照组,SOD和CAT高于对照组(P0.05),实验组大鼠的肝组织匀浆中MDA水平也显著低于对照组,SOD和CAT高于对照组(P0.05)。实验组肝脏超微结构的损伤程度和细胞凋亡程度均较对照组有所减轻。结论他克莫司能在一定程度上保护脂肪肝供体大鼠肝移植围手术期移植物的功能,其作用机制可能与其抑制脂质过氧化、细胞凋亡和减轻再灌注损伤有关。     

他克莫司撤药诱发大鼠肝移植急性排斥反应的病理学观察与分析

目的建立大鼠肝移植急性排斥反应动物模型,观察大鼠肝移植术后他克莫司撤药诱发受体急性排斥反应的肝脏动态病理学变化,为临床肝移植术后他克莫司停药或者用药不规律所致急性排斥反应的预测和评估提供理论依据。方法通过Kamada二袖套法,建立雄性DA大鼠至Lewis大鼠的原位肝移植模型60例。受体大鼠术前1 d和术后7 d内饲喂治疗剂量的他克莫司,之后半量递减至停药。分别于术后7、14、21及28 d处死部分受体大鼠,获取肝组织标本,观察受体大鼠肝脏大体和镜下的动态病理学改变,并进行排斥活动指数评分,同时观察受体大鼠的术后生存时间。结果受体大鼠术后7 d内由于受他克莫司的保护,肝脏未出现典型的急性排斥反应表现,至术后14 d由于他克莫司的减量及撤出,迅速发生肝脏的急性排斥反应,术后14、21及28 d排斥活动指数评分分别为(3.7±0.9)分(、6.3±0.9)分和(8.1±0.7)分。受体术后生存时间为(20.85±0.71)d,中位生存期为21 d。结论通过围手术期短期饲喂治疗剂量他克莫司并逐渐减量至撤药诱发肝移植大鼠急性排斥反应模型术后的急性排斥反应,动态观察该实验条件下排斥反应发生的时限和严重程度,对临床肝移植术后类似情况下所发生的急性排斥反应具有一定的预测价值和严重程度评估价值。     

他克莫司在大鼠肝脏保存中的作用

目的了解他克莫司对肝脏缺血再灌注损伤的保护作用。方法在供肝保存期间向保存液中加入他克莫司,检测保存12 h后的肝脏能量物质负荷、肝移植术后受体大鼠血清中的肝酶浓度以及胆汁分泌情况。结果保存液中加入他克莫司后,肝组织在保存期间的能量物质消耗明显小于对照组,移植术后受体大鼠血清中ALT和LDH含量明显较对照组为低,胆汁分泌量则明显高于对照组,差异均具有显著性(P0.05)。结论他克莫司用于肝脏保存能够有效地减轻缺血再灌注损伤,提高肝细胞能荷,改善移植术后的肝脏功能。     

他克莫司和雷帕霉素对肝癌肝移植患者Foxp3+ Treg的影响及防治排斥反应的研究

目的 探讨免疫抑制剂他克莫司和雷帕霉素对肝癌肝移植受者Foxp3+ Treg产生的影响及其防治排斥反应的疗效.方法 自移植后第2个月到第12个月,每月采血,采用实时荧光定量PCR法检测他克莫司组和雷帕霉素组肝癌肝移植受者新鲜外周血单个核细胞中Foxp3 mRNA的表达水平,通过同期术后观察和实验室检查,比较两组受者间Foxp3 mRNA表达水平和急性排斥反应发生率的差异.结果 他克莫司组受者的外周血单个核细胞中Foxp3 mRNA表达水平(0.1032±0.0943)明显低于雷帕霉素组受者(1.2136±0.6738),差异有统计学意义(t=5.1610,P＜0.01);雷帕霉素组患者比同期他克莫司组受者术后急性排斥反应发生率明显减低,差异有统计学意义(x2=2.2222,P＜0.05).结论 他克莫司抑制了肝癌肝移植术后免疫耐受的诱导,而雷帕霉素可能参与了免疫耐受的诱导和维持;雷帕霉素对肝癌肝移植受者防治排斥反应的效果更好.     

初始灌注液对离体低温保存大鼠肝脏的影响

目的 探讨缺血再灌注过程中初始灌注液对离体低温保存大鼠肝脏的影响。方法采用离体大鼠肝脏低温缺血保存再灌注模型90例,分别选择UW液、HC-A液和乳酸林格液作为不同的初始灌注液,观察大鼠肝脏在低温保存0、3、6、12、24 h后再灌注流出液中ALT、AST、LDH和ET的水平,同时比较3组之间肝脏细胞形态和细胞凋亡。结果 使用HC-A液作为初始灌注液的大鼠肝脏再灌注流出液中ALT、AST、LDH和ET水平较其他两组低(P<0.05),肝脏形态和细胞凋亡的发生3组差异无显著性。另外,上述指标均受低温保存时间的影响。结论 初始灌注液可影响离体低温保存大鼠肝脏的质量,细胞凋亡可能参与了肝脏的缺血再灌注损伤。     

调整免疫抑制方案应权衡临床疗效与毒性

环孢素A(CsA)或他克莫司(FK506)联合抗增免疫抑制剂和皮质类固醇的免疫抑制方案可获得较低的急性排斥反应(AR)发生率和较好的移植物存活率.     

潘生丁对大鼠移植肝缺血再灌注损伤保护作用的实验研究

目的探讨潘生丁对大鼠移植肝缺血再灌注损伤的保护作用及其相关机制。方法采用改良Kam ada“二袖套法”制作肝移植模型,48只雄性SD大鼠随机分成3组:假手术组(A组),同基因大鼠肝移植组(B组)和潘生丁预处理 同基因大鼠肝移植组(C组)。于供肝再灌注2 h后测定各组PAGT、ALT、AST、SOD、MDA含量,比较肝细胞凋亡和组织形态学改变。结果移植肝再灌注2 h后C组较B组肝组织损害轻,SOD、MDA、ALT、AST、PAGT变化及肝细胞凋亡差异有显著性(P<0.05)。结论潘生丁可通过改善肝脏微循环状况,改善缺血肝脏组织的能量代谢,提高肝组织抗氧化能力,抑制细胞凋亡和减少肝脏细胞的变性坏死程度而对肝脏热缺血再灌注起保护作用。     

他克莫司在肾移植中应用新进展

他克莫司（普乐可复）是从放线菌属中提取出来的一种新型强效免疫抑制剂。近年来,他克莫司被广泛应用于肝脏、肾脏、心脏和胰腺等实体器官移植领域,对于预防术后急性排斥反应有良好的疗效。肾移植术后服用他克莫司预防急性排斥反应的患者比例逐年增加,     

CYP3A5在肝移植术后他克莫司个体化治疗中的意义

目的总结CYP3A5在肝移植术后他克莫司个体化治疗中的意义。方法复习、分析近年来有关肝移植患者CYP3A5基因多态性对他克莫司药代动力学影响的文献。结果他克莫司可以有效预防肝移植的排斥反应。药代动力学中狭窄的有效药物浓度范围和个体差异使其很难确定针对所有患者的固定剂量,药物代谢酶和转运子的基因多态性影响着他克莫司的血药浓度。CYP3A5基因分型影响着肝移植受体的他克莫司需要量。结论 CYP3A5基因分型可能为优化肝移植患者的免疫抑制治疗提供帮助。     

他克莫司缓释胶囊在肝移植中应用的优势

他克莫司缓释胶囊(商品名新普乐可复)是每天服用1次的新型制剂,它将进一步改善移植受者的依从性.已经使用环孢素A或使用2次/d他克莫司胶囊的肝移植受者可以转换为他克莫司缓释胶囊,初始肝移植受者也可以直接应用他克莫司缓释胶囊. 众所周知,器官移植受者中依从性不佳者非常普遍,而在供者器官短缺日益严重的今天,如何改善依从性,优化受者及移植物的中长期预后,成为大家更为关注的热点问题.不同的研究中心所报道的依从性差的发生率高达22％～55％.但实际工作中,依从性差所导致的移植物功能丧失常常被低估.研究提示[1],与依从性良好的受者相比,依从性差的受者急性排斥反应的发生率更高,移植物功能丧失的发生率更高.他克莫司缓释胶囊究竟是否能改善肝移植受者的依从性呢?Beckebau等[2]的一项研究中给出了答案.     

血清CINC浓度在大鼠肝移植后急性排斥反应中的意义

目的 探讨嗜中性粒细胞趋化因子（ＣＩＮＣ）在肝移植后再灌注损伤和急性排斥反应发生时的作用。方法 施行了３组大鼠原位肝移植。即：（１）ＡＣＩ大鼠－ＬＥＷ大鼠组;（２）ＢＮ大鼠－ＬＥＷ大鼠组;（３）ＬＥＷ大鼠－ＬＥＷ大鼠组。分别为高度排斥反应组,中度排斥反应组和对照组。结果 大鼠肝移植后血清ＣＩＮＣ浓度与正常大鼠相比明显增加（Ｐ〈０．００１）,同时嗜中性粒细胞总数和天冬氨酸转氨酶（ＡＳＴ）及丙氨酸转氨     

Apoptosis and the expression of Fas and Fas ligand (FasL) antigen in rejection and reinfection in liver allograft specimens

BACKGROUND AND METHODS: To investigate the frequency of apoptosis and the expression of Fas/Fas ligand (FasL) in liver allografts, we examined 97 biopsy specimens from 62 patients after orthotopic liver transplantation. The results of the biopsies were as follows: acute allograft rejection (n=32); hepatitis C virus (HCV) reinfection (n=18); cytomegalovirus infection (n=5); acute rejection plus HCV reinfection (n=3); and stable graft function (n=30); and after treatment of acute rejection (n=9). RESULTS: Apoptotic cells were found in all cases examined, and their frequency increased significantly during acute rejection (0.17 vs. 9.0; P<0.05). The immunoreactivity of Fas and FasL antigen was higher in specimens with acute rejection than in those with stable graft function. Increased apoptosis, Fas, and FasL expression, however, were also seen in HCV reinfection. CONCLUSION: We conclude that apoptosis plays an important role in the hepatocellular damage observed in acute rejection and also in HCV reinfection. However, these parameters are, taken by themselves, not useful as indicators of acute rejection or HCV reinfection.     

Beta-glucan reflects liver injury after preservation and transplantation in dogs.

Graft failure and extrahepatic organ complications, which frequently develop after transplantation, may be related to inflammatory mediators stimulated by endotoxin (ET). The role of endotoxemia after liver transplantation is controversial and may depend upon differences in the ET assay method used in the various contradicting studies. While the standard Limulus amebocyte lysate (LAL) is reactive for ET and beta-glucan, a novel turbidimetric assay method enables separate determinations of ET and beta-glucan. Beagle dogs undergoing orthotopic liver transplantation were divided into two groups. In Group I (n = 6) the grafts were transplanted immediately and in Group II (n = 6) grafts were preserved for 48 h in University of Wisconsin (UW) solution. Animals received cyclosporine immunosuppression and were followed for 14 days. Daily measurements of aspartate aminotransferase (AST), alanine aminotransferase (ALT), and lactate dehydrogenase (LDH) were performed. Samples for ET and beta-glucan measurement were collected serially and processed using the turbidimetric assay method. While no graft failure was seen in Group I, three of six Group II animals died from graft failure within 1 day after transplantation. Preservation and reperfusion injury was much more severe in the Group II grafts than in Group I grafts. While endotoxemia could not be detected, postoperative beta-glucan levels (undetectable pretransplant) were seen in both groups. Beta-glucan levels were much higher in Group II grafts than in Group I grafts, and correlated with the severity of liver damage. In conclusion, this study shows that beta-glucan, instead of ET, appears during the early posttransplant period. We believe that posttransplant elevation of beta-glucan is related to liver damage, especially endothelial damage by preservation and reperfusion.     

Prevention of primary nonfunction after canine liver allotransplantation: the effect of gadolinium chloride

PURPOSE: Effective suppression of Kupffer cell function is believed to contribute to the prevention of preservation/reperfusion injury. In this study, effect of gadolinium, a synthetic Kupffer cell suppressant, on the reperfusion injury was examined using a canine partial liver transplantation model. METHODS: About a 70% partial liver segment was harvested and reimplanted in a mongrel recipient dog weighing 20 to 25 kg. Gadolinium chloride (10 mg/kg) was infused via the cephalic vein 24 hours before harvest of the partial liver (gadolinium group, n = 5). Serum aspartate aminotransferase (AST), alkaline phosphatase (ALP), lactate dehydrogenase (LDH), and morphologic grading of graft were compared with those of a control group (n = 5). Statistical analysis was done with an independent t-test. RESULTS: Average total ischemic time was 4 hours and 27 minutes. At 1 hour after reperfusion, there were no significant differences in AST, ALP, or LDH levels, or pathologic scores. At 48 hours after reperfusion, AST (P = .03) and LDH (P = .05) levels were significantly lower in the gadolinium group. CONCLUSION: Kupffer cell blockade using gadolinium chloride may be effective to reduce ischemia reperfusion injury, but the effect is not evident at an early stage of reperfusion.     

UTI和丹参在鼠肝脏缺血再灌注中对肝窦内皮细胞损伤保护效应的实验研究

目的：探讨UTI和丹参在肝脏缺血再灌注中对肝窦内皮细胞损伤的保护作用。方法：将大鼠肝脏缺血再灌注模型30只大鼠分为5组，A组为空白对照组（n=3），B组为缺血再灌注组（n=7），C组为UTI组（n=6），D组为丹参组（n=6），E组为UTI＋丹参组（n=8）。除A组外，在缺血30min再灌注120min后分别取血检测AST、ALT、LDH、HA及ET，并取肝组织行光镜和电镜观察。结果：C组、D组较B组各指标明显下降（P〈0．01），E组各指标较C组或D组均有下降，（P〈0．05）。光镜和电镜观察形态学损伤程度，B组最重，C组、D组次之，E组最轻。结论：UTI、丹参在缺血再灌注中能有效减轻对肝窦内皮细胞的损伤，二药合用有协同作用。     

乙型肝炎病毒携带者肾移植后应用他克莫司和环孢素A对肝功能影响的比较

目的 探讨乙型肝炎病毒携带者肾移植术后应用他克莫司（FK506）和环孢素A（CsA）对肝功能的影响。方法 73例乙型肝炎病毒（HBV）携带者接受肾移植，术前患者的肝功能正常，HBVDNA阴性。术后将患者分为两组：FK506组40例，术后服用FK506、霉酚酸酯（MMF）及泼尼松（Pred）预防排斥反应；CsA组33例，术后服用CsA、MMF及Pred预防排斥反应。术后追踪随访1～6年，观察两个组患者肝功能损害情况以及HBVDNA阳性率，发生肝功能损害时，调整免疫抑制剂的用量，并给予护肝治疗。结果 术后FK506组有4例（10．0％）、CsA组有16例（48．5％）发生肝功能损害，FK506组有2例（5．0％）、CsA组有9例（27．3％）HBVDNA转阳性，两组比较，差异均有统计学意义（P＜0.05）。CsA组肝功能损害的16例中，10例将CsA切换为FK506，另6例治疗方案不变，结果转换药物者肝功能恢复正常的时间明显短于未转换者（P〈0．01），且治疗1～2周时的丙氨酸转氨酶、天冬氨酸转氨酶和胆红素总量的水平也明显低于未转换者（P＜0．05，P＜0．01）。结论 与CsA相比，乙型肝炎病毒携带者肾移植术后应用FK506可降低肝功能损害的发生率，减少乙型肝炎复发。     

缺血预处理对大鼠移植肝脏微循环的保护作用

目的：探讨早期再灌注损伤中缺血预处理（IP）对大鼠移植肝脏微循环的保护作用。方法：采用SD大鼠原位肝移植动物模型，供肝冷保存时间100min，无肝期25min。32只SD大鼠随机平均分成两组，每组16只。对照组：获取供肝前仅以肝素生理盐水经门静脉灌注；IP组；获取供肝前阻断肝门血供10min，再灌注10min，然后再以肝素生理盐水经门静脉灌注。移植肝脏再灌注2h后取血及肝脏检测。结果：IP组的肝脏抗氧化酶活力明显高于对照组（P＜0．01），血清丙氨酸转氨酶（ALT）、门冬氨酸转氨酶（AST）、乳酸脱氢酶（LDH）及肝组织中的过氧化产物丙二醛（MDA）含量均明显低于对照组（P＜0．001）；肝组织损伤以窦状内皮细胞为主，并且是以凋亡的方式发生死亡，IP组窦状内皮细胞损伤明显轻于对照组（P＜0．001）。结论：IP对大鼠移植肝脏微循环的早期再灌注损伤有保护作用。     

Alleviation of ischemia-reperfusion injury in rat liver transplantation by induction of small interference RNA targeting Fas

Background Cellular apoptosis plays an important role in ischemia-reperfusion (I/R) injury during organ transplantation. Synthetic small interference RNA (siRNA) targeting apoptotic receptor Fas has proven effective to protect mice against hepatitis and renal I/R injury. The objective of this study is to investigate the silencing impact of Fas siRNA to alleviate I/R injury in rat liver transplantation. Materials and methods Rat hepatocytes (BRL cells) were transfected with three pairs of synthesized Fas siRNA; cells untreated and treated with GFP siRNA were taken as blank and siRNA control. The most effective Fas siRNA was chosen for in vivo experiments. Syngeneic orthotopic liver transplantation was performed in Fas siRNA group, siRNA control group, and blank control group of Sprague–Dawley rats. There were 25 pairs of rats in each group. siRNA transfection of donor rats was done with hydrodynamic injection method 48 h before liver procurement. Blood and liver samples were collected for evaluation of serum ALT levels, Fas protein and mRNA expression, and apoptosis by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) staining, 1, 3, 6, 12, and 24 h after liver transplantation. Results Fas siRNA2, which inhibited Fas gene expression much more than other siRNAs, was chosen for in vivo experiment. The serum ALT levels of Fas siRNA group were much less than those of blank and siRNA control groups 1, 3, 6, 12, and 24 h after blood reperfusion, indicating diminishing ischemia-reperfusion injury. Donor livers in Fas siRNA group had substantially less cell apoptosis. The expression of Fas mRNA and protein was reduced dramatically in the Fas siRNA group compared with the other two groups. Conclusion Fas-mediated apoptosis play an important role in I/R injury of rat liver transplantation. Silencing Fas by hydrodynamic injection of siRNA holds therapeutic promise to limit I/R injury.