Reduced immunogenicity of rat renal allografts after photochemical donor pretreatment and passive transfer of graft protection

Summary Photochemical pretreatment of the kidney donor (Sprague-Dawley rats/SD) with 8-methoxypsoralen (8-MOP) and ex vivo longwave ultraviolet (UVA) irradiation of the kidney graft (PUVA therapy) significantly prolonged survival in allogeneic recipients (BD IX rats). After more than 100 days 7 long-term surviving PUVA-pretreated SD kidneys were retransplanted into BD IX rats. Seven out of 7 secondary recipients survived for more than 100 days. Twenty BD IX recipients of normal SD kidneys were treated at the time of transplantation with serum (1 ml i.v.) and/or spleen lymphocytes (1x10⁷ i.v.) obtained from the PUVA-treated long-term survivors. A prolonged graft survival was achieved in 7 our of 20 rats, among them 4 out of 8 recipients of the serum-treated group. In conclusion, the long-term survival of PUVA-treated rat renal allografts is associated with a strong reduction of graft immunogenicity and the development of graft protecting humoral as well as cellular effectors.     

负向免疫调节树突状细胞对心脏移植大鼠免疫状态的影响

目的 探讨经体外光化学法(PUVA)处理的供者脾淋巴细胞与受者树突状细胞(DC)共培养后,对移植受者体液免疫、细胞免疫及移植物排斥反应的影响.方法 以DA大鼠为供者,LEW大鼠为受者,建立大鼠腹部异位心脏移植模型.分离供者脾淋巴细胞(SP),制备经PUVA处理的供者脾淋巴细胞(PUVA-SP).在体外分别将供者PUVA-SP和SP与受者骨髓来源的未成熟DC共培养,得到PUVA-SP-DC及SP-DC,流式细胞仪检测上述DC表型.根据受者心脏移植术前1周静脉输注成分的不同,将受者随机分为3组:(1)对照组(n=7):单纯输注磷酸盐缓冲液(PBS);(2)SP-DC组(n=8):输注Sp-DC 5×106个;(3)PUVA-SP-DC组(n=8):输注PUVA-SP-DC 5×106个.每日观察各组移植心的存活状况.移植后第6天,检测受者血清中抗供者特异性IgG水平;通过混合淋巴细胞反应(MLR)检测受者脾脏T淋巴细胞对供者抗原刺激的增殖反应;比较各组受者脾脏体积的大小.结果 供者脾淋巴细胞经PUVA处理后细胞凋亡率为81.93%.正常LEW大鼠DC共刺激分子CD80和CD86阳性率分别为(3.5±0.27)%和(13.0±0.58)%,受者DC与供者SP混合培养后,其CD80和CD86的表达水平为(16.6±0.72)%和(36.5±0.87)%,后者明显高于前者(P<0.01);受者DC与供者PUVA-SP混合培养后,其CD86和CD80的表达率分别为(3.9±0.12)%和(13.4±0.59)%,与正常LEW大鼠DC相当(P>0.05).PUVA-SP-DC组的受者抗供者特异性IgG水平明显低于SP-DC组及对照组(P<0.01).PUVA-SP-DC组受者T淋巴细胞对供者抗原的刺激反应指数为1.66±0.29,明显低于SP-DC及对照组(7.28±0.38、4.19±0.16,P<0.01);而其对无关供者抗原的刺激反应指数为4.37±0.11,与SP-DC及对照组相当(4.51±0.40、4.36±0.14,P>0.05).PUVA-SP-DC组的移植心存活时间比其他两组明显延长(P<0.01),而且其脾脏体积最小.结论 PUVA-SP-DC能够特异性的下调移植受者对供者抗原的细胞免疫及体液免疫反应,从而明显延长移植物存活时间.     

Synergistic effect of donor pretreatment with 8-methoxypsoralen and ultraviolet irradiation of the graft plus azathioprine and prednisolone therapy in prolonging rat renal allograft survival

Summary Pretreatment of the kidney donor with 8-methoxy-psoralen (8-MOP) and direct longwave ultraviolet (UVA) irradiation of the kidney graft (PUVA therapy) significantly prolonged survival in allogeneic recipients. 40% of the recipients survived more than 100 days with normal transplant function. The addition of standard clinical immunosuppressive agents azathioprine and prednisolone (both at dosages of 15 mg/kg body weight/day for 21 days) to the PUVA therapy further improved graft survival rate, with a recipient survival rate of 62.5%. The two drugs alone were less effective in prolonging graft survival rate (28.5%). A synergistic effect of PUVA therapy and standard immunosuppressive treatment with azathioprine and prednisolone was demonstrated. This suggested a possible clinical application of this type of immunosuppression and immunoregulation.     

Sensitization interval and administration method alter the effect of 15-deoxyspergualin on heart transplantation in sensitized recipient rats

We evaluated the effect of 15-deoxyspergualin (DSG) on accelerated rejection. Brown Norway rats (BN) served as organ donors and Lewis rats (LEW) as recipients. In an accelerated rejection model, after a LEW rat was sensitized with BN skin, a BN heart was transplanted. Various intervals between sensitization and heart transplantation were examined. The heart allografts in sensitized recipients were rejected earlier than those in unmodified recipients regardless of the sensitization interval. DSG (2.5 mg/kg per day), given to the recipients during the sensitization phase, significantly prolonged graft survival compared with the untreated hosts when the sensitization interval was short. When the recipients were treated with DSG after heart transplantation, heart graft survival was significantly prolonged regardless of the sensitization interval. Flow cytometric analysis and complement-dependent cytotoxicity tests revealed that DSG suppressed antidonor antibody formation and that postoperative administration of DSG significantly decreased the proliferation of B cells when the sensitization interval was short and the proliferation of class II antigen-positive cells when the sensitization interval was long.     

Changes in blood ketone body ratio with reference to graft viability after liver transplantation in rats

Arterial blood ketone body ratio (acetoacetate/3-hydroxybutyrate; KBR), which reflects hepatic mitochondrial redox potential, was measured during a 2-week period after orthotopic liver transplantation in three groups of rats: group 1, the isogenic combination of LEW (RT1¹) graft to LEW recipient as control; group 2, the allogenic combination of ACI (RT1^a) graft to LEW recipient without immunosuppressive treatment; and group 3, the allogenic combination of ACI to LEW with immunosuppressive treatment using cyclosporin (CyA). Isogenic recipients survived indefinitely. Allogenic recipients in group 2 had severe rejection with a mean survival of 10.3±0.54 days, while 77.8% of the allogenic recipients in group 3 survived more than 30 days. KBR of rats surviving more than 2 weeks in groups 1 and 3 gradually increased post-transplantation and was maintained at a high level. By contrast, though KBR in group 2 was restored at 3 days, it gradually fell and remained at a significantly low level (P<0.001). It is suggested that KBR provides an accurate indicator for evaluating metabolic viability of the critically deteriorating liver graft accompanied by severe rejection.     

Synergistic Effect of Photochemical Donor Pretreatment and Cyclosporin Therapy of the Recipient on Rat Renal Allograft Survival

Dose-response studies of cyclosporin (CsA) established thatdoses of 2 mg/kg body weight on 4 consecutive days (0–3)or higher gave complete suppression of rejection and permanentsurvival of all rat kidney allografts, while a dose of 2 mg/kgbody weight on day 0 was much less effective in preventing deleteriousrejection (30% permanent survival). Photochemical pretreatmentof the kidney donor with 8-methoxypsoralen (8-MOP) and directlong-wave ultraviolet irradiation (UVA) of the kidney (PUVAtherapy) significantly prolonged the subsequent graft survivalin allogeneic recipients. Forty per cent of the animals survivedmore than 100 days. However, when PUVA-treated kidney allograftswere transplanted into temporary CsA immunosuppressed recipients(2 mg/kg on day 0) the graft survival rate was further improved.Seventy per cent of the PUVA + CsA-treated recipients survivedpermanently. Therefore, a synergistic effect of PUVA pretreatmentand low-dose CsA therapy on rat renal allograft survival wasdemonstrated. The results suggested a possible clinical application of thistreatment regimen in order to avoid high nephrotoxic CsA doses.     

Effects of PUVA therapy on kidney allografts: results of a randomized prospective double-blind study

Abstract After successful experimental organ transplant studies on the efficacy of PUVA therapy combining donor pretreatment with the photosensitizer 8-methoxypsoralen (P) and the ex vivo irradiation of organs with long-wave ultraviolet light (UVA) prior to transplantation, we started in 1989 the first randomized, prospective, double-blind study to clarify the efficacy of PUVA therapy in human kidney tiansplantation. This study included 50 kidney donors, 25 of whom were PUVA-treated. A total of 75 kidneys were transplanted in Berlin, Halle and Rostock. The complete data of these 75 recipients were available for the final evaluation. The PUVA group ( n = 36) and the non-PUVA group ( n = 39) were not statistically significantly different as to donor and recipient data. Regarding the results, no differences were seen in initial hospitalization time, early graft function, rejection rate, number and time of rejection episodes. After a follow-up of 24 months, both graft survival (PUVA vs. non-PUVA: 75% vs. 71.8%) and patient survival (97.2% vs. 97.4%, respectively) were comparably high. PUVA therapy did not influence the development of vascular rejection. Interestingly, the rate of late graft loss after the 6th posttransplant month was lower, but not statistically significantly so, in the PUVA than in the non-PUVA-group (2 vs. 6 graft losses). Thus, PUVA-pretreated kidneys may be associated with a reduced development of chronic rejection.     

Transplantation of allogeneic fetal pancreases combined from MHC-different donor strains does not change rejection of the graft

A number of 17.5- to 18.5-day-old fetal pancreases were grafted under the kidney capsule of streptozotocin-diabetic rats. Eight syngeneically grafted glands were sufficient to reverse the diabetes of the recipients within 4 weeks when the recipient rats were treated with insulin for 18 days after transplantation. Eight allogeneic fetal pancreases obtained from one donor strain were rejected after transplantation and the recipients relapsed into hyperglycemia immediately after insulin withdrawal. Eight allogeneic fetal pancreases obtained from eight MHC-different donor strains were also rejected and the recipients relapsed into hyperglycemia after insulin withdrawal. Using fetal pancreases as tissue sources, the combination of the allogeneic graft from different donor strains was not sufficient to prolong the survival time of the grafted tissue.     

Short- and long-term success of organs transplanted from acute methanol poisoned donors

BACKGROUND: The shortage of organs for transplantation has made it necessary to extend the criteria for the selection of donors, among others including those patients who die because of toxic substances such as methanol. Methanol is a toxic which is distributed through all the systems and viscera of the organism and tends to cause a severe metabolic acidosis. It can specifically cause serious or irreversible lesions of the central nervous system (CNS) and retina, and ultimately brain death. We present our experience with 16 organ donors who died as a result of acute methanol intoxication in 10 Spanish hospitals over the last 14 yr. PATIENTS AND METHODS: Between October 1985 and July 1999, 16 organ donors with brain death caused by acute methanol intoxication, 13 females and three males with a mean age of 38.4 +/- 7.6 yr (interval: 26-55 yr), allowed 37 elective transplants to be performed: 29 kidneys, four hearts and four livers for 37 recipients, and one urgent liver transplantation to a recipient with fulminant hepatitis. RESULTS: The immediate postoperative period was favourable for the 38 graft recipients. None of the graft recipients presented gap anion metabolic acidosis in the immediate postoperative period, nor symptomatology or lesions of the CNS characteristic of methanol intoxication. Two patients died during the first month post-transplantation, a liver recipient and a heart recipient, at 16 and 24 days, respectively, because of acute rejection of the graft. At 1 month after transplantation 35 of the 36 recipients had been discharged from hospital with normal-functioning grafts. The last of the recipients, a kidney recipient, was discharged at 6 wk with normal-functioning graft. Actuarial survival of the graft and patient of kidney recipients at 1, 3 and 5 yr was 92.6, 77.8, and 75%, and 100, 88.9 and 83.3%, respectively; with average serum creatinines of 139.9 +/- 42.9, 150.4 +/- 42.8, and 164.4 +/- 82.5 micromol/L, respectively. At 1 yr after transplantation the three heart recipients and two of the three liver recipients had normal-functioning graft. CONCLUSIONS: Methanol intoxication is not transferred from the donor to the recipient. The survival of the graft and kidney, heart and liver recipients using organs from donors who die because of methanol does not differ in the short- and long-term from the transplants performed with organs from donors who die from other causes.     

Changes in blood ketone body ratio with reference to graft viability after liver transplantation in rats

Abstract. Arterial blood ketone body ratio (acetoacetate/3-hydroxybutyrate; KBR), which reflects hepatic mitochondria] redox potential, was measured during a 2-week period after orthotopic liver transplantation in three groups of rats: group 1, the isogenic combination of LEW (RT1^l) graft to LEW recipient as control; group 2, the allogenic combination of ACI (RT1^a) graft to LEW recipient without immunosuppressive treatment; and group 3, the allogenic combination of ACI to LEW with immunosuppressive treatment using cyclosporin (CyA). Isogenic recipients survived indefinitely. Allogenic recipients in group 2 had severe rejection with a mean survival of 10. 3 ± 0. 54 days, while 77. 8% of the allogenic recipients in group 3 survived more than 30 days. KBR of rats surviving more than 2 weeks in groups 1 and 3 gradually increased post-transplantation and was maintained at a high level. By contrast, though KBR in group 2 was restored at 3 days, it gradually fell and remained at a significantly low level ( P < 0. 001). It is suggested that KBR provides an accurate indicator for evaluating metabolic viability of the critically deteriorating liver graft accompanied by severe rejection.     

雷公藤多甙在大鼠胰、十二指肠移植中的作用

目的 解胰腺移植术后应用雷公藤多甙对移植胰腺功能存活的影响。方法 供体为雄性Ｗｉｓｔｅｒ大鼠,受体为雄性ＳＤ大鼠。受体经尾静脉注射链脲霉素５０ｍｇ／ｋｇ制备成糖悄病大鼠模型。胰腺４移植受用全胰腺、十二指肠移植,胰岛素回流采用门腔静脉吻合的体循环回流,外分泌胰液采用 受体十二指肠间侧侧吻合的肠引流法。血管吻合采用显微外科技术。胰腺移植术后开始每隔采用供受体十二指肠间侧侧吻合的肠引流法。血管吻合采用显     

Donor hypo‐ and hypernatremia are predictors for increased 1‐year mortality after cardiac transplantation

Donor hypernatremia is known to be associated with initial graft dysfunction in liver transplantation. Controversial data exist regarding the impact of sodium dysregulation on patient survival after heart transplantation (HTX). The aim of this study was to investigate the influence of donor sodium levels on survival in a large cohort of heart transplant recipients from the Eurotransplant registry. From 1997 to 2005, all consecutive adult HTX performed in the Eurotransplant region were included into this study (n = 4641 patients). Multivariate analysis was applied to investigate possible clinical predictors for 1‐year post‐transplant survival after cardiac transplantation (donor sodium levels, donor age, donor cause of death, recipient age, primary disease, urgency status, cold ischemia time). In multivariate analysis, recipients receiving a donor heart with serum sodium level lower than 130 mmol/l or higher than 170 mmol/l had a 1.25‐fold higher risk for 1‐year post‐transplant mortality than patients with normal donor sodium ranges (P = 0.007). Other independent risk factors for impaired 1‐year survival were recipient age, the indication for transplantation and the urgency status of the recipient. Our study demonstrates that hyponatremia as well as hypernatremia show a strong U‐shaped correlation with poor survival after cardiac transplantation. Accurate donor management to avoid electrolyte disorder seems to be crucial for ensuring good quality of donor hearts.     

The superior effect of the combination of FK 506 and deoxyspergualin on rat cardiac allograft survival

In this present study, the effects of FK 506 and 15-deoxyspergualin (DSG), with respect to dose, timing, and combination, were investigated in an ACI-to-LEW rat cardiac allograft model. FK 506 was adminstered intramuscularly for 14 days starting on day 0 after grafting, while DSG was given intraperitoneally for 7 days starting on day 0,4, or 7 after transplantation. FK 506 or DSG monotherapy prolonged cardiac allograft survival in dose-dependent manners, and the minimum effective dose for overcoming rejection was 0.1 mg/kg per day in the case of FK 506 and 1.0 mg/kg per day for DSG. The graft survival rate was higher with administration of DSG starting on day 4 on day 0 after transplantation. A low dosage of FK 506 strating on day 0, in combination with DSG starting on day 0 or day 4 (but not on day 7), had a synergistic effect in prolonging allograft survival for 14.0±3.3 days and 25.4±8.2 days, respectively. The most effective combination treatment schedule for prolongation of allograft survival was FK 506 starting on day 0 and DSG starting on day 4 after transplantation.     

Optical tissue window: a novel model for optimizing engraftment of intestinal stem cell organoids

BACKGROUND: The pre-transplant administration of donor antigens to recipients is reported to prolong transplanted organ survival. We investigated the effect of pre-transplant intraportal administration of recipient blood on rat hepatic allograft survival. MATERIALS AND METHODS: Male LEW (RT1l) and ACI (RT1a) rats were used as transplant recipients and donors, respectively. Before transplantation, donors were transfused with recipient blood. Experimental animals were divided into groups as follows: group I, no treatment; group II, pre-treatment with recipient blood via the penile vein 7 days before transplantation; group III, pre-treatment with recipient blood via the portal vein 5 days before transplantation; and group IV, pre-treatment with recipient blood via the portal vein 7 days before transplantation. Serum interferon (IFN)-gamma concentrations were measured post-operatively. RESULTS: Animals in group I survived a mean of 10.1 +/- 0.7 days. The survival of groups II and III was 10.6 +/- 1.6 and 13.1 +/- 0.9 days, respectively. The survival rate in group IV was prolonged significantly to 33.7 +/- 2.6 days. Serum concentrations of IFN-gamma were increased significantly in group IV, as compared with group I. The ratio of OX76+CD4+ or OX76+CD8+ T cells to OX76-CD4+ or OX76-CD8+ T cells was greater in group IV, as compared group I. OX76+CD8+ T cells from hepatic allografts in group IV expressed IFN-gamma and interleukin (IL)-10, but not IL-2 mRNA. Apoptotic hepatic infiltrates were greater in group IV, as compared to group I. CONCLUSION: The cytokine profile of donor CD8+ T cells from allografts treated by the intraportal administration of recipient blood is associated with apoptosis of graft-infiltrating cells and the prolonged survival of hepatic allografts in rats.     

Recent trends in early outcome of adult patients after heart transplantation: a single-institution review of 251 transplants using standard donor organs.

Older age, prior transplantation, pulmonary hypertension, and mechanical support are commonly seen in current potential cardiac transplant recipients. Transplants in 436 consecutive adult patients from 1994 to 1999 were reviewed. There were 251 using standard donors in 243 patients (age range 18-69 years). To emphasize recipient risk, 185 patients who received a nonstandard donor were excluded from analysis. The indications for transplant were ischemic heart disease (n = 123, 47%), dilated cardiomyopathy (n = 82, 32%), and others (n=56, 21%). One hundred and forty-nine (57%) recipients were listed as status I; 5 and 6% were supported with an intra-aortic balloon and an assist device, respectively. The 30-d survival and survival to discharge were 94.7 and 92.7%, respectively; 1-year survival was 89.1%. Causes of early death were graft failure (n = 6), infection (n = 4), stroke (n = 4), multiorgan failure (n = 3) and rejection (n = 2). Predictors were balloon pump use alone (OR= 11.4, p =0.002), pulmonary vascular resistance > 4 Wood units (OR = 5.7, p = 0.007), pretransplant creatinine > 2.0 mg/dL (OR = 6.9, p = 0.004) and female donor (OR = 8.3, p = 0.002). Recipient age and previous surgery did not affect short-term survival. Heart transplantation in the current era consistently offers excellent early and 1-year survival for well-selected recipients receiving standard donors. Early mortality tends to reflect graft failure while hospital mortality may be more indicative of recipient selection.     

Enhancement of the immunosuppressive effect of cyclosporin A by ciprofloxacin in a rat cardiac allograft transplantation model

Ciprofloxacin hyperinduces interleukin-2 production in stimulated human and mouse lymphocytes. In this study, an enhanced and prolonged interleukin-2 response was also detected in polyclonally stimulated rat splenocytes in the presence of ciprofloxacin (5–80g/ml) compared to control cells without any antibiotic. Ciprofloxacin was able to counteract the immunosuppressive effect of 10ng/ml cyclosporin A (CyA) but did not interfere with higher CyA concentrations. In parallel, ciprofloxacin did not influence thymidine uptake in mixed lymphocyte reactions in the presence of CyA. To obtain an in vivo application of these findings, graft survival was studied by performing rat cardiac allograft transplantations in the presence or absence of CyA. Brown Norway rats served as donors and Wistar Furth rats as recipients. Ciprofloxacin was injected intraperitoneally either at a high-dose regimen (240 mg/kg per 24h) into rats every 8th h starting 1 day before transplantation until day 21 or graft loss, or it was injected at a low and clinically relevant dose regimen (45mg/kg per 24h) until day 9. CyA was administered orally (10mg/kg per 24h) from day 1 through day 9. Ciprofloxacin given alone at a high-dose regimen resulted in a median graft survival of 14.8 days, which was significantly longer than graft survival in rats without treatment (median 8.0 days). A low-dose regimen of ciprofloxacin alone did not affect graft survival. Ciprofloxacin at a highdose regimen combined with CyA prolonged graft survival to a median of 24.0 days compared to 20.5 days with CyA alone. Ciprofloxacin administered in the drinking water (200mg/kg per 24h) until day 9 in addition to CyA did not affect graft survival. However, when the same dose regimen was used in experiments with PVG rats as donors and Wistar/Kyoto as recipients, graft survival was significantly prolonged to a median of 45 days. Ciprofloxacin, given orally without the addition of CyA, did not influence graft survival in either of the two strain combinations. Thus, our data show that ciprofloxacin has no negative impact on heart graft survival rats. It remains to be clarified whether ciprofloxacin influences graft survival in humans.     

三种小体积肝移植大鼠模型的比较

目的 通过对三种供肝选取方法的比较来探索更简便、稳定的小体积肝移植大鼠模型的建立方法.方法 以Kamada"二袖套"法非动脉化原位大鼠肝移植模型为基础,采取供肝冷灌洗后原位剪除肝叶的方法获取供肝,建立小体积肝移植模型,Ⅰ组以肝中叶作为供肝,Ⅱ组以肝右中叶+右叶作为供肝,Ⅲ组以肝中叶+右叶作为供肝,其中Ⅰ组及Ⅱ组供、受者体重相似,Ⅲ组供者体重比受者轻100～120 g.比较3个组的手术成功率、手术各阶段耗时、术后肝功能以及移植肝组织损伤、排斥反应发生、手术并发症和受者存活情况.结果 Ⅲ组肝叶剪除时间为(8.8±0.7)min,明显短于Ⅱ组的(11.5±1.1)min和Ⅰ组的(10.1±1.0)min(P＜0.01).3个组供肝冷缺血时间、无肝期及受者手术耗时等方面的差异无统计学意义.Ⅲ组肝断面出血和胆漏并发症显著少于Ⅰ组和Ⅱ组;Ⅰ组肝后下腔静脉狭窄及血栓形成明显多于Ⅱ组和Ⅲ组(P＜0.05).3组间术后第1、7天血清丙氨酸转氨酶、胆红素总量和血氨水平的差异无统计学意义.术后第7天,3组间肝损伤及排斥反应分级(Banff分级均为轻度)的差异均无统计学意义.Ⅰ组、Ⅱ组和Ⅲ组的手术成功率分别为80%、85%和85%,3组间的差异无统计学意义.Ⅲ组的7 d存活率为62.5%,高于Ⅰ组的42.9%和Ⅱ组的47.5%,但3组间的差异无统计学意义.Ⅲ组的存活时间为(12.0±2.3)d,长于Ⅰ组的(6.0±0.9)d和Ⅱ组的(7.0±1.3)d,但差异均无统计学意义.结论 采用肝中叶+右叶供肝和供者体重低于受者100～120 g的方案能够简便、快捷的建立稳定的30%小体积肝移植大鼠模型,而且能显著减少肝切除相关并发症.

Abstract：

Objective To explore a simple and effective way of establishing a 30 % small-forsize liver transplantation in rats. Methods SD rats were selected as the donors and recipients. Smallfor-size orthotopic live transplantation was performed using Kamada's two-cuff method. Donor's liver was flushed via abdominal aorta and hepatectomy in situ was done. Animals were divided into 3 groups (40 pairs of rats in each): group Ⅰ , median lobe was used as graft; group Ⅱ, right of median lobe and right lobe were used as graft; group Ⅲ, median and right lobes were used as graft. The body weight of the donor was the same as the recipient in groups Ⅰ and Ⅱ , but 100～ 120 g less than in group Ⅲ. The operating time, 7-day survival and technical complications were compared among these 3 groups. Results The operating time of hepatectomy was shorter in group Ⅲ than in groups Ⅰ and Ⅱ (8. 8±0.7 vs 11.5± 1.1 vs 10.1 ±1.0 min, P＜0.01). The cold ischemia time of graft, the anhepatic time, the operating time of recipient and the transplanting successful rate showed no significant difference among the 3 groups. Compared with groups Ⅰ and Ⅱ , the incidence of bleeding,bile leakage and IVC stricture was significantly decreased in group Ⅲ (P＜0. 05). Other complications after operation showed no significant difference among the 3 groups (P＞0. 05). Group Ⅲ had more 7-days survivors and longer median survival time, but there was no significant difference among the 3groups. Conclusion Small for donor body weight with median and right lobes as graft was a more effective and simple way of establishing a 30 % small-for-size liver transplantation in rats with shorter hepatectomy time and less complications after operation.     

The Evolution of Nonimmune Histological Injury and Its Clinical Relevance in Adult-Sized Kidney Grafts in Pediatric Recipients

To describe the evolution, risk factors and impact of nonimmune histological injury after pediatric kidney transplantation, we analyzed 245 renal allograft protocol biopsies taken regularly from the time of transplantation to 2 years thereafter in 81 consecutive rejection-free pediatric recipients of an adult-sized kidney. Isometric tubular vacuolization was present early after transplantation was not progressive, and was associated with higher tacrolimus pre-dose trough levels. Chronic tubulo-interstitial damage and tubular microcalcifications were already noted at 3 months, were progressive and had a greater association with small recipient size, male donor gender, higher donor age and female recipient gender, but not with tacrolimus exposure. Renal function assessment showed that older recipients had a significant increase in absolute glomerular filtration rate with time after transplantation, which differed from small recipients who showed no increase. It is concluded that progressive, functionally relevant, nonimmune injury is detected early after adult-sized kidney transplantation in pediatric recipients. Renal graft ischemia associated with the donor-recipient size discrepancy appears to be a greater risk factor for this chronic histological injury, suggesting that the exploration of additional therapeutic approaches to increase allograft perfusion could further extend the graft survival benefit of adult-sized kidneys transplanted into small children.     

小鼠骨髓间充质干细胞减轻胰岛移植物排斥反应的作用

目的 探讨同种异基因小鼠骨髓间充质干细胞(MSC)与胰岛联合移植对胰岛移植物的免疫调节作用.方法 将18只糖尿病模型小鼠随机分成3组:(1)糖尿病组,不进行任何移植;(2)胰岛移植组,在无菌操作下将10μl纯化后的200个胰岛移植于受者的左肾包膜下;(3)胰岛+MSC移植组,除与胰岛移植组进行相同的移植外,还在胰岛移植前3、2、0d经受者尾静脉分别注射1×106个MSC.移植后,连续监测非空腹血糖至第30 d;第14和28 d对移植部位的左肾进行组织病理学观察;采集外周血进行免疫荧光染色,流式细胞术分析TH1/TH2、Tc1/Tc2细胞的比值、初始和记忆T淋巴细胞的变化、以及骨髓来源的树突状细胞(DC)成熟度和功能的变化.结果 与胰岛移植组比较,胰岛+MSC移植组血糖明显降低,移植部位炎症细胞浸润明显减轻,移植物的存活时间延长;TH1和Tc1细胞明显下降,TH2和Tc2细胞升高,TH1/TH2和Tc1/Tc2细胞比值显著下降;初始T淋巴细胞和记忆T淋巴细胞下调;DC成熟度降低,分泌白细胞介素12(IL-12)的能力下降.结论 MSC与胰岛联合移植可通过对T淋巴细胞和树突状细胞的免疫调节作用,减轻胰岛移植物的排斥反应,从而延长移植胰岛的存活时间.     

Generation of donor hematolymphoid cells after rat-limb composite grafting

BACKGROUND: Composite tissue allografts are unique because they provide the vascularized bone marrow with stroma, which is the supportive microenvironment. In this study, we investigated the beneficial effect of donor-derived bone marrow cells within the long-surviving recipient rats after limb transplantation. METHODS: Green fluorescent protein (GFP) transgenic rats developed for paramount cell marking were donors, and wild Wistar rats were recipients. Orthotopic hind-limb transplantation was performed using a microsurgical technique. Tacrolimus (1.0 mg/kg) was intramuscularly injected for 14 days postoperatively. The skin graft from GFP donor onto the GFP recipient was performed as a control. Flow cytometric analyses of recipient peripheral blood and bone marrow were carried out at 4 to 6 days, 18 to 21 days, 6 weeks, and 2, 4, 6, 9, and 12 months after transplantation. RESULTS: The rats that received tacrolimus therapy achieved prolonged composite graft acceptance more than 12 months, whereas GFP skin grafts were rejected at 47 days under the same immunosuppressive protocol. Numerous GFP lymphocytes and granulocytes were detected within the recipient bone marrow for the first 6 weeks post limb transplantation. These cells remained relatively stable for more than 12 months. CONCLUSIONS: The results showed that donor-derived hematopoietic stem cells engrafted in recipient bone marrow and differentiated to lymphocytes and granulocytes after limb transplantation. The vascularized bone marrow, transplanted as a part of the hind limb, could have contributed to mixed chimerism and worked as the bone-marrow source in the recipients.