Value of mucosal biopsies in the monitoring of acute small bowel rejection

The value of mucosal biopsies in evaluating small bowel rejection is controversial. In this study, the value of mucosal biopsies was estimated in unmodified porcine small bowel rejection. Ten animals received the distal half of the small bowel as a heterotopic loop (Thiry-Vella loop). The allografts were followed by proximally and distally harvested full-thickness and mucosal biopsies every other day, starting from the 3rd day and continuing until the grafts became necrotic. The histological parameters in both types of biopsies were semiquantitatively scored from 0 to 3 and compared with each other. The difference in mean values on subsequent days was not remarkable, the results favoring slightly higher values in full-thickness than in mucosal biopsies. Our results suggest that multiple mucosal biopsies are adequate in monitoring morphological changes of small bowel grafts during rejection and that the proximal and distal ileum are similarly affected by acute rejection. Received: 17 June 1996 Received after revision: 20 November 1996 Accepted: 6 December 1996     

一氧化氮在大鼠小肠移植缺血再灌注损伤和急性排斥反应中的作用

目的 探讨一氧化氮(NO)在大鼠小肠移植缺血再灌注损伤(IRI)和急性排斥反应(AR)中作用.方法 建立同种大鼠原位小肠移植模型,采用随机数字表法将受鼠分为4组.移植对照组、左旋精氨酸(L-Arg)组、左旋硝基精氨酸甲酯(L-NAME)Ⅰ组(Ⅰ组)和L-NAMEⅡ组(Ⅱ组)受鼠于手术当天开始分别每天给予生理盐水、L-Arg 150 mg·kg-1 ·d-1、L-NAME 4和8 mg·kg-1·d-1.术后观察各组受鼠的存活时间,行HE染色观察移植小肠的组织病理学改变,采用免疫组织化学法观察移植小肠一氧化氮合酶(NOS)的活性,以及检测血糖吸收功能和血清NO浓度.结果 移植对照组、L-Arg组、Ⅰ组及Ⅱ组受鼠的存活时间分别为(11.7±1.2)d、(10.2±1.0)d、(12.3±1.5)d和(17.3±1.9)d,Ⅱ组受鼠的存活时间明显延长(P＜0.01).与移植对照组相比,L-Arg组和Ⅰ组IRI的Park评分下降,IRI减轻;Ⅱ组Park评分显著升高(P＜0.01),IRI加重,但AR明显减轻.与移植对照组相比,IRI期间,Ⅰ组iNOS染色减弱,Ⅱ组iNOS和nNOS染色均减弱;AR期间,Ⅱ组iNOS染色明显减弱.各组血清NO浓度于再灌注后30min逐渐升高.与移植对照组相比,Ⅱ组血 NO浓度的升高延缓.与移植对照组相比,L-Arg组血糖吸收值于再灌注30 min至术后3d明显增高(P＜0.01);Ⅰ组和Ⅱ组血糖吸收值术后处于较低水平.结论 NO在大鼠小肠移植IRI中起到了细胞毒和细胞保护的双重作用;在AR中加重了组织损伤.术后早期补充L-Arg可促进移植肠管对糖类的吸收.     

Phenotypic and functional characteristics of intestinal intraepithelial lymphocytes during acute rejection of small intestinal allografts

Infiltration of a transplanted organ by host lymphoid cells is the hallmark of acute rejection. However, after intestinal transplantation, physiological lymphocyte migration may lead to host cell infiltration of the graft even in the absence of rejection. It is unclear whether this lymphocyte migration also involves the intraepithelial compartment of the graft or whether infiltration there is indicative of acute rejection. We demonstrate here that host cell infiltration of the intestinal mucosa occurs both during acute rejection of a small bowel allograft and, to a lesser extent, when rejection is prevented by immunosuppression with FK506. The infiltrating host cells consisted of CD3 ⁺ T cells with a predominant CD4^–CD8 ⁺ phenotype resembling intraepithelial lymphocytes (IELs). Functional studies showed that the nonspecific cytolytic activity of IELs was not affected by acute rejection or by immunosuppression with FK506. These findings indicate that host cell infiltration of the intestinal mucosa does not connote an ongoing acute rejection. Furthermore, the decreased mucosal barrier function during acute rejection of intestinal allgrafts is probably not due to impaired cytolytic activity of IELs. Received: 10 March 1997 Received after revision: 6 November 1997 Accepted: 19 November 1997     

Intramucosal pH and intestinal mucosal damage in ischemia-reperfusion injury

Small bowel transplantation (SBT) has become an increasingly promising treatment for short bowel syndrome. The evaluation of graft viability after SBT, however, has not been established, except by mucosal biopsy. We monitored intestinal mucosal acidity in order to detect small intestinal ischemia-reperfusion injury. Mongrel dogs were used in this study. After laparotomy, the small bowel was isolated with a vascular pedicle. A tonometer to measure intramucosal pH (pHi) was then positioned in the terminal ileum. The superior mesenteric artery was occluded with or without concomitant superior mesenteric vein occlusion for 60 or 120 min. The value of pHi was determined from laparotomy (baseline) to 12 h after reperfusion. Whole-thickness specimens of the ileum were taken before ischemia, just before reperfusion, and 1 h afterward. Mucosal injury was graded histopathologically. pHi decreased from baseline in relation to the degree of histopathological mucosal injury. There was a significant correlation between histological findings and the change in pHi. We conclude that monitoring intestinal mucosal acidity is a reliable way of determining graft viability after SBT. Received: 19 February 1998 Received after revision: 27 July 1998 Accepted: 15 September 1998     

辅助性同种异体肝肠联合移植术后急性排斥反应的监测

目的评价猪同种异体辅助性肝肠联合移植术后排斥反应的监测方法。方法将50头杂交长白猪分为3组．A、B组各20头各完成10次猪辅助性带胰头及十二指肠的同种异体肝肠联合移植术．其中B组术后予以免疫抑制治疗：C组10头完成交互的同种异体节段性小肠移植术10例。术后1、3、5、7、14、21及30d经移植肠远端造口取小肠黏膜经常规处理后。分别在光镜和电镜下观察并进行排斥反应评分。结果术后A组出现排斥反应的中位时间为8（7～12）d．迟于c组的5（3～5）d（P〈0．05）。术后1周,A组的排斥反应评分为1．11±0．20。低于C组（2．56±0．18,P〈0．05）;但比B组高（O．20±0．13,P〈O．05）。A组移植术后中位存活时问为9（7～25）d,C组为12（7～20）d．而B组术后全部成活超过30d．与以上两组比较,P〈0.05．差异有统计学意义。结论移植术后排斥反应通过肠造口取材进行监测方便有效。     

Is patchy tubular injury a histopathological marker of acute rejection?

Abstract:  Renal allograft specimens often show patchy tubular injury (PTI), or patches of injured tubular sections. PTI reflects damage to the proximal tubules, and the histologic findings consist of tubular cell necrosis and tubular regeneration without tubulitis. Unlike acute tubular necrosis (ATN) in cadaveric donors, PTI can be observed in kidneys from living donors when there is no history of acute renal failure after transplantation. In this study, we examined the clinicopathological importance of PTI in acute rejection. Between April 2000 and May 2007, 2252 biopsies of living kidney grafts were performed at least one d after the transplant operation. Acute rejection was observed in 877 biopsies. Of these cases, 78 (8.9%) biopsies from 43 patients showed PTI. The severity of the PTI was graded semiquantitatively as follows: grade 1 cases had three or four damaged tubular sections, grade 2 cases had >5 sections, and grade 3 cases had >10 sections. The incidence of PTI was significantly higher in vascular rejection (VR) and antibody-mediated rejection (AMR) patients than in those experiencing tubulointerstitial rejection (TIR). The mean PTI score was significantly higher (2.00 ± 0.12) in VR than in TIR (1.39 ± 0.10) and AMR (1.68 ± 0.08) patients. The mean serum creatinine (sCr) at the time of biopsy was higher in VR patients than in AMR and TIR patients. Moreover, in VR patients, those with severer PTI developed higher sCr levels. These data suggest that PTI has a strong relationship with local ischemic damage delegated by VR, and the severity of PTI could be a practical histological marker in acute vascular rejection.     

Selective treatment of early acute rejection after liver transplantation: Effects on liver,infection rate,and outcome

To evaluate the results of selective treatment of biopsy-proven mild acute rejection episodes, we retrospectively studied 1-week liver biopsies of 103 patients with a primary liver graft in relation to liver function tests. The overall incidence of rejection was 35 %. In four patients the biopsy showed histological features consistent with rejection; in 27 patients it showed mild acute rejection (grade 1), and in 5 patients it showed moderate acute rejection (grade 2). Study group 1 consisted of 19 untreated patients with grade 1 rejection and group 2 of 8 treated patients with grade 1 rejection. At 30 and 90 days, no differences in liver function tests were found. The infection rate, histology after 1 year, and survival in the two groups did not differ. It may, therefore, be concluded that withholding treatment in histologically proven mild acute rejection is possible in selected patients based on histological, biochemical, and clinical criteria. This may reflect the functional diversity of morphologically similar lymphocytic infiltrates observed in graft biopsies showing features of mild acute rejection.Liver Transplant Group     

Selective treatment of early acute rejection after liver transplantation: effects on liver, infection rate, and outcome

Abstract To evaluate the results of selective treatment of biopsy-proven mild acute rejection episodes, we retrospectively studied 1-week liver biopsies of 103 patients with a primary liver graft in relation to liver function tests. The overall incidence of rejection was 35 %. In four patients the biopsy showed histological features consistent with rejection; in 27 patients it showed mild acute rejection (grade 1), and in 5 patients it showed moderate acute rejection (grade 2). Study group 1 consisted of 19 untreated patients with grade 1 rejection and group 2 of 8 treated patients with grade 1 rejection. At 30 and 90 days, no differences in liver function tests were found. The infection rate, histology after 1 year, and survival in the two groups did not differ. It may, therefore, be concluded that withholding treatment in histologically proven mild acute rejection is possible in selected patients based on histological, biochemical, and clinical criteria. This may reflect the functional diversity of morphologically similar lymphocytic infiltrates observed in graft biopsies showing features of mild acute rejection.     

小鼠肠移植术前输注表达吲哚胺2,3双加氧酶的供者树突细胞抑制排斥反应

目的观察干扰素γ(IFN-γ)诱导供者(C57BL/6小鼠)脾树突细胞(DC)表达吲哚胺2,3双加氧酶(IDO)的情况;研究受者(BalB/c小鼠)小肠移植术前输注高表达IDO的供者DC对排斥反应的抑制作用。方法用IFN-γ诱导供者DC表达IDO;半定量逆转录聚合酶链反应、免疫印迹法及毛细管电泳法检测IDO表达水平及活性,混合淋巴细胞培养(MLR)测定IDO刺激T细胞增殖的能力。利用小鼠异位小肠移植模型,设单纯移植组、DC输注移植组(术前输注供者脾DC 2×10~6个)及诱导DC输注移植组(术前输注经IFN-γ诱导的供者脾DC 2×10~6个),术后观察移植肠存活时间并行病理学检查。结果经IFN-γ诱导的脾DC IDO分子mRNA转录水平(相对量)、IDO蛋白表达水平(相对量)及培养液中犬尿氨酸浓度分别为(1.23±0.02)、(2.74±0.01)以及(76.52±0.44)μmol/L,未经IFN-γ诱导的脾DC分别为(1.05±0.05)、(1.40±0.17)及(43.31±0.48)μmol/L,前者显著增强(P<0.01)。脾DC对同种T细胞增殖的刺激作用在IFN-γ诱导后减弱,在加入IDO的特异性抑制剂后增强。输注诱导DC移植组移植肠中位存活时间(12 d)较单纯移植组(6 d)及输注DC移植组(7.5 d)显著延长(P<0.01),而移植肠病理分级显著性降低(P<0.05)。结论IFN-γ可诱导小鼠脾DC高表达活性的IDO,后者可减弱DC刺激T细胞增殖的能力。受者术前输注高表达IDO的供者DC能够诱导针对供者的特异性免疫耐受而减轻排斥反应。     

肝移植急性排斥反应的诊断与治疗

目的 总结肝移植术后急性排斥反应(AR)的诊治经验。方法 回顾性分析57例肝移植患者术后AR的发生率和治疗结果。结果 21例患者术后因肝功能异常而行38次移植肝活检(术后6～91d)，11例15次发生AR，其中8例为单次，3例为两次或两次以上，轻度11次，中重度4次，AR发生率为19．3％(11／57)。20次为单纯保存-再灌注损伤(PRI)。3次为药物中毒。所有AR均经激素冲击或调整FK506剂量后缓解。结论 移植肝活检对于AR的诊断与鉴别诊断有重要意义，只要给予及时的诊断与治疗，AR一般是可逆的。     

小肠移植术后内镜引导下移植肠黏膜活检的时机及诊断价值

目的 总结小肠移植术后内镜引导下移植肠黏膜活检的时机及该技术对急性排斥反应和感染的诊断价值.方法 根据免疫抑制方案的不同,将15例小肠移植受者分为3个阶段.1994-1995年为第1阶段(3例),2003-2006年为第2阶段(7例),2007年以后为第3阶段(5例).第3阶段进行计划性内镜引导下移植肠黏膜活检的监测,既术后第3天进行首次内镜引导下移植肠黏膜活检,此后活检的频次在术后第1个月为2次/周,术后第2～3个月为1次/周,术后第4～6个月为1次/2周,术后7个月以后为1次/月,在受者出现排斥反应的临床症状和抗排斥反应治疗期间,也进行内镜引导下移植肠黏膜活检.结果 15例共进行内镜引导下移植肠黏膜活检255次,移植肠腹壁造口肉眼直视下取材活检21次.以上276份样本中,诊断排斥反应共51份(18.5%),其中诊断不确定急性排斥反应至轻度排斥反应32份(11.6%)、中度排斥反应9份(3.3%)、重度排斥反应10份(3.6%),巨细胞病毒(CMV)感染2份(0.7%),细菌感染2份(0.7%).15例共发生病理证实并需l临床治疗的排斥反应20次,其中不确定急性排斥反应至轻度排斥反应11次、中度5次、重度4次,发生细菌性和CMV肠炎各1次.结论 内镜引导下移植肠黏膜活检及其病理学检查是小肠移植术后诊断排斥反应和感染的重要手段,有计划的进行该检查对排斥反应有术后监测、早期诊断、鉴别诊断和指导治疗的价值.     

Histamine-degrading enzymes as cellular markers of acute small bowel allograft rejection

Intestinal histamine-degrading enzymes diamine oxidase (DAO) and histamine N-methyltransferase (HNMT) activities are relatively constant per individual and bowel segment, and they reflect the functional integrity of the intestinal mucosa. It was, therefore, hypothesised that a decrease in these enzymes could be indicative of acute rejection of an intestinal allograft. Enzymatic activities of DAO and HNMT were determined in mucosal biopsies of isogeneic (Lewis-to-Lewis, n=48) and allogeneic (Brown Norway-to-Lewis, n=48) heterotopic small bowel transplants in a rat model at various time periods. Allograft recipients were not given any immunosuppression. While no changes in enzyme activities were observed in isografts up to day 8 following transplantation, significantly reduced activities of both enzymes were found in all allografts 6-8 days after transplantation. Activities of both DAO and HNMT exhibited a strong negative correlation with the histological rejection score ( P<0.01). We can conclude that DAO and HNMT activities in gut mucosa are reliable quantitative markers of acute intestinal allograft rejection in the rat that support histopathological analysis.     

心肺联合移植中供者心、肺的保护及术后排斥反应的诊断和治疗二例

目的 探讨心肺联合移植中供者心、肺的保护措施,以及术后免疫抑制方案、排斥反应的临床诊断及其处理.方法 回顾分析2例心肺联合移植的临床资料.2例供肺的灌洗分别使用Perfadx保护液(每1000 ml加入氨基丁三醇0.3 ml,伊洛前列素25 μg)和Euro Collins(EC)保护液(每1000 ml加入氨基丁三醇0.3 ml,前列地尔100 μg).供心的灌洗使用UW液.心肺联合移植采用经典原位技术.免疫抑制方案采用巴利昔单抗诱导,术后采用环孢素A+吗替麦考酚酯+皮质激素.术后早期观察受者的血象变化,各器官功能,各心腔大小及室间隔、左室后壁厚度等,必要时行胸部CT、纤维支气管镜及组织病理检查,及时发现排斥反应征象.受者发生排斥反应后给予皮质激素冲击治疗,并及时调整免疫抑制剂用量.结果 2例受者分别于术后第80天和第141天康复出院,分别随访4年6个月与4年2个月,现生活质量良好.1例受者于术后第10天和第26天发生急性排斥反应,另1例受者于术后第29天和第87天发生急性排斥反应,均经皮质激素冲击治疗,并调整免疫抑制剂用量后逆转.当受者发生急性排斥反应时,往往伴有血象的变化及室间隔和左心室后壁厚度的增加,给予相应治疗后渐恢复至正常范围.结论 Perfadx保护液和EC保护液对供肺均有较好的保护作用,UW液对供心有较好的保护作用;术后及时发现排斥反应与感染,并采取恰当的处理措施有利于受者顺利康复.

Abstract：

Objective To summarize the preservation measures of the donor's heart and lung, and the postoperative immunotherapy, as well as the clinical experience of discrimination and management for graft rejection.Methods The clinical data of 2 cases of heart-lung transplantation in our department were retrospectively analyzed. Two different protective liquids were used for donor's lung lavage of 2 cases: Perfadx solution (1000 mL containing tris 0.3 mL and ilomedin 25 μg); Euro Collins solution (1000 mL containing tris 0.3 mL and PGE1 100 μg). UW solution was used for donor's heart lavage. Surgical procedure for heart-lung transplantation was classic technique in situ. The schedule of immunosuppression was induced by Basiliximab, and combined with cyclosporine+ mycophemolate mofeil+corcal hommone after operation. recipient's blood count, organ's functions, the sizes of every cavity of heart, IVSPW and LVPW were observed during early post-operation. The recipients were subjected to chest CT scan, fiberoptic bronchoscope and tissue pathological study when necessary to find the signs of rejection promptly. When the rejection occurred in the recipient, cortical hormone's impulse therapy was given and the dose of immunosuppression was adjusted in time.Results Two patients discharged in 80 days and 141 days after operation. The patients were followed up for 54 months and 50 months respectively, and their life qualities were very well. Acute rejections occurred on the 10th and 26th day in one case, and in another case, acute rejections occurred on the 29th and 87th day after operation. All were conversed by cortical hormone's impulse therapy and adjusting the dose of immunosuppressants. When acute rejection occurred, the blood count had significant change, and IVSPW and LVPW were increases. They were returned the normal range after corresponding therapy.Conclusion Perfidx solution and Euro-Collin solution may play good protective roles for donor's lungs. UW solution may play good a protective role for donor's heart. To discriminate the clinical graft rejection and infection in time and administrate correct management will have large benefits for the patients' rehabilitation.     

Mucosal recipient-type mononuclear repopulation and low-grade chronic rejection occur simultaneously in indefinitely surviving recipients of small bowel allografts

Lewis rat recipients of long-term, surviving, orthotopic Brown-Norway rat intestinal allografts, initially treated with cyclosporin A (CyA) or FK 506, were evaluated for their functional capacity and morphology over 1 year after the immunosuppressive therapy had been discontinued. Functional parameters such as nitrogen and fat balances, maltose absorption, blood chemistry, hematologic studies, and the weight gained by the allografted animals did not differ from those of syngeneically grafted or agematched normal animals. Immunohistochemical studies showed that the lamina propria of the allografts was repopulated with recipient MHC class II+mononuclear cells and that a normal distribution of T helper, T suppressor/killer, and IgA+plasma cells had occurred. However, fibrous replacement of the mesenteric lymph nodes and Peyer's patches were detected in all, and an inflammatory obliterative arteriolopathy developed in the mesenteric vasculature of half of the allografted animals. No such findings were observed in recipients of syngeneic grafts. These results demonstrate that the limited use of potent immunosuppressive agents immediately after transplantation averts rejection and is followed by recipient-type mucosal lymphocytic repopulation. Simultaneously, a clinically not recognizable chronic rejection evolves. This suggests that the timely diagnosis of chronic rejection may not be possible with the use of standard tests of gut function and random mucosal biopsies alone.This study was presented in part at the 32nd Annual Meeting of the Society for Surgery of the Alimentary Tract, 21–22 May 1991, New Orleans, Louisiana     

大鼠肾下腹主动脉阻断后再灌注自由基变化对肾功能影响实验研究

目的 探讨大鼠肾下腹主动脉阻断后再灌注自由基变化对肾功能的影响及其作用机制.方法 Wistar大鼠42只,随机分为对照组,缺血5 h组,缺血5 h分别再灌注2、4、8、12 h组,每组7只.检测血清尿素氮(BUN)、肌酐(Cr)及血浆和肾组织匀浆丙二醛(MDA)、超氧化物歧化酶(SOD)水平,光镜观察各组大鼠肾脏及下肢肌肉形态学变化.结果 缺血及再灌注组大鼠BUN水平较对照组高,差异有统计学意义(P<0.05),在I/R4 h组达到最高,随后下降;各组间Cr差异无统计学意义.大鼠血浆MDA水平在对照组与I组,L/R 2 h组,I/R4 h组,I/R 8 h组,I/R 12 h组组间比较差异有统计学意义(P<0.05),血浆MDA水平在I/R 4 h组达到高值,随后下降.大鼠血浆SOD水平在对照组与I/R 4 h组,I/R 8 h组组间比较差异有统计学意义(P<0.05);大鼠肾组织匀浆SOD水平在I/R4 h组与对照组,I组,I/R 2 h组,I/R 8 h组.I/R 12 h组组间比较差异有统计学意义(P<0.05),SOD水平在I/R 4 h组达到低值,随后升高.光镜观察缺血组肾脏及下肢肌肉组织可见轻度损伤,再灌注组肾脏及下肢肌肉组织损伤程度较缺血组重.结论 大鼠肾下腹主动脉阻断后再灌注可造成肾功能异常,与缺血再灌注所激发的自由基合成及释放增多有关.     

肾移植术后耐激素急性排斥反应的诊治体会

目的 总结肾移植术后耐激素的急性排斥反应(steroid-resistant acute rejection,SRAR)的诊治体会.方法 对32例SRAR患者的临床资料进行回顾性分析.所有患者经临床表现、移植肾彩色多普勒超声(彩超)检查、移植肾穿刺病理活组织检查(活检)诊断为SRAR并分型.确诊后采用抗胸腺细胞球蛋白(...     

小肠移植急性排斥反应中bcl-2及bax表达的意义

目的探讨bcl-2及bax的异常表达与小肠移植急性排斥反应的关系。方法选用近交系F344/N和封闭群Wistar/A大鼠建立同种异基因小肠移植模型,并随机分为同基因移植组、异基因移植组、异基因加普乐可复(FK506)治疗组和对照组,用免疫组织化学技术检测36只大鼠术后移植肠组织中bcl-2及bax在移植肠组织中的表达。结果异基因组术后第3天,bcl-2的表达显著低于对照组(P<0.05),并随着移植天数的增加,差异更加具有显著性意义(P<0.01);bax的表达与对照组比较差异无显著性意义(P>0.05);FK506治疗组bcl-2及bax表达与对照组比较,差异均无显著性意义(P>0.05)。结论移植肠组织内bcl-2表达水平可作为早期诊断急性排斥反应的一个有参考意义的指标。     

Levels of HBV-DNA and HBsAg after acute liver allograft rejection treatment by corticoids and OKT3

The aim of this work was to analyze whether the treatment of acute rejection of orthotopic liver transplants (OLT), either with corticoids or OKT3, has any effect on the levels of hepatitis B virus (HBV)-DNA and HBsAg in individuals which were originally affected by cirrhosis or fulminant hepatic failure as a result of B virus. We have found that HBV-DNA is present in macrophages, B cells and both CD4+ and CD8+ T cells after OLT in all cases studied. Interestingly, the levels of HBV-DNA and HBsAg in the serum analyzed were increased extremely rapidly in the patients treated with OKT3 in an acute rejection episode. However, the serum levels of HBV-DNA and HBsAg found were lower when the patients were treated with steroids, and were not found in non-treated patients. As the serum levels of HBV-DNA increase, the process of liver reinfection could be accelerated; therefore, these results may help to understand how OKT3 and corticoids immunosuppressive therapy may accelerate the reinfection of OLT by HBV. In conclusion, our results suggest that special care must be taken in the use of OKT3 in the treatment of acute liver rejection episodes in chronic or fulminant HBV transplanted patients.