Apoptosis and treatment of chronic allograft nephropathy with everolimus

BACKGROUND: Chronic allograft nephropathy (CAN) is responsible for most cases of late kidney allograft loss. However, no effective treatment is available so far. Everolimus (RAD) (40-O [2-hydroxyethyl] rapamycin) is a new immunosuppressive agent with antiproliferative and apoptosis-enhancing effects. We asked whether everolimus can ameliorate CAN even at advanced stages, whether everolimus treatment affects the level of growth factor mRNA, and whether everolimus treatment affects the number of apoptotic cells in the graft. METHODS: We transplanted kidneys from Fisher rats into Lewis rats and treated recipients with everolimus over different time periods. Grafts were analyzed 20 or 28 weeks after transplantation. RESULTS: Everolimus delayed the progression of CAN when started at an early stage. Surprisingly, everolimus even ameliorated CAN when initiated at an advanced stage. Interestingly, apoptosis was more prevalent in treated animals, particularly in those with delayed treatment as compared with controls. CONCLUSIONS: Everolimus ameliorates CAN as a result of antiproliferative or apoptosis-enhancing effects.     

Immunopathogenesis of accelerated allograft rejection in sensitized recipients: humoral and nonhumoral mechanisms

INTRODUCTION: Accelerated rejection (AccR) in sensitized recipients (second-set rejection) is considered a classic humorally mediated form of allograft rejection, although additional effector mechanisms may be involved. METHODS: We developed a model of AccR in which C57BL6 mice are sensitized by BALB/c skin grafts, followed 10 days later by transplantation of BALB/c hearts. We undertook analysis of various humoral and cellular components in this model using knockout or monoclonal antibody-treated allograft recipients. RESULTS: Sensitized mice rejected cardiac allografts in 34+/-7 hr. AccR was accompanied by endothelial deposition of immunoglobulins, complement, and fibrin, but also by dense expression of multiple chemokines and a mixed polymorphonuclear and mononuclear cellular infiltrate. Whereas neutrophil or complement depletion had no significant effect on the tempo of AccR, surprisingly B cell-deficient recipients still underwent AccR (41+/-7 hr) in conjunction with T cell and macrophage recruitment. In contrast, T cell-deficient (nude) mice maintained functioning cardiac allografts for >720 hr despite prior skin engraftment. CONCLUSIONS: AccR in sensitized experimental recipients involves multiple effector pathways. Although most previous studies have emphasized the key role of humoral pathways in mediating AccR, our data indicate that T cell-dependent mechanisms can also promote AccR, alone or in conjunction with humoral responses.     

大鼠慢性移植肾肾病动物模型的制作经验总结

目的 总结制作稳定的大鼠慢性移植肾肾病(CAN)动物模型的经验.方法 以F344近交系大鼠为供者,取供者左肾作为供肾,原位低温灌注;以Lewis近交系大鼠为受者,行左侧原位肾移植,供肾动脉与受者腹主动脉端侧吻合,供肾静脉与受者肾静脉端端吻合,输尿管带膀胱瓣与受者膀胱吻合.术后用环孢素A灌胃10 d,剂量为10 mg·kg-1·d-1.每月采集受者血液和尿液,测定血肌酐及24 h尿蛋白,分别于术后2、4个月获取移植肾进行病理检查.结果 45只进行移植,手术成功率为85%,单次手术时间为(120±20)min.移植后1个月,大鼠即出现血肌酐、尿素氮及血胱抑素升高,24 h尿蛋白增加,与术前相比,各项指标均升高(P<0.05);术后2个月及4个月,除尿蛋白继续增加外,其余观察指标上升不明显.移植术后2个月,移植肾有轻度至中度的间质纤维化,淋巴细胞和浆细胞的浸润;4个月时,移植肾可见广泛的间质纤维增生,间质细胞大量浸润,肾小球基底膜增厚、硬化、闭塞,肾小管萎缩退化,符合CAN的病理改变.结论 通过充分的手术强化训练及改进,规范大鼠取、肾、移植术中、术后管理的每个细节,大鼠CAN模型的成功率及稳定性高.

Abstract：

Objective To summarize the experience of establishing the stable rat model of chronic allograft nephropathy. Methods We used Fisher rats as donors and Lewis rats as recipients.After the left kidney of the donor perfused in situ under hypothermic condition, the left renal vein,abdominal aorta and bladder flap of the donor was anastomosed with the left renal vein, renal artery and bladder of the recipient, respectively. The recipients were given cyclosporin oral solution 10 mg/kg every day by gavage for 10 days after transplantation. The blood and urine samples were collected 1 month, 2 months and 4 months after transplantation and renal function and total urine protein were examined. The pathological changes of the renal allograft were observed 2 and 4 months after transplantation. Results Forty-five rats received operation and achievement ratio was 85%. The renal transplantations were finished in 120 ± 20 min. The Scr, BUN, Cycs and total urine protein demonstrated a significant increase one month after transplantation. On the second and fourth month,with the exception of urine protein continued to increase, the other indicators did not change significantly. Two months after transplantation renal pathology demonstrated light to moderate interstitial fibrosis, infiltration of lymphocytes and plasma cells. At 4th month the renal allografts showed extensive interstitial fibrosis, a large number of infiltrating interstitial cells, thickening,hardening, occlusion of glomerular basement membrane, and renal tubular atrophy that were consistent with pathological changes of chronic allograft nephropathy. Conclusion Through adequate surgical training and improvement, and specification for rat nephrectomy, transplantation surgery,and postoperative management in every detail, the model with high success rate and stability can be achieved.     

Alloreactivity in renal transplant recipients with and without chronic allograft nephropathy

The pathogenesis of chronic allograft nephropathy (CAN) involves both immunologic (antigen-dependent) and nonimmunologic (antigen-independent) mechanisms. In order to provide further insight into the immunologic basis of this disease, a cross-sectional analysis of cellular and humoral immunity in human renal allograft recipients with or without deteriorating renal function and biopsy proven CAN was performed. Interferon-gamma enzyme-linked immunosorbent spot assays were used to assess cellular immunity to donor, or fully mismatched third-party stimulator cells (direct pathway), and to synthetic peptides derived from donor HLA molecules (indirect pathway). Anti-HLA antibodies were evaluated by flow cytometry using HLA-coated beads. Both the mean frequencies of donor-reactive peripheral blood lymphocytes and the number of individuals who responded to donor antigens per group were statistically higher in CAN patients versus control subjects (P < 0.02). Calculated ratios of donor/third-party enzyme-linked immunosorbent spot responses showed mean values of 2.61 +/- 3.0 in the CAN group, with ratios of 0.50 to 0.72 +/- 0.42 in control subjects (P < 0.001), confirming that direct, donor-specific cellular immunity predominated in patients with CAN. Fifty percent of CAN patients studied exhibited donor peptide reactivity compared with only 28.6% in control subjects. Finally, 33% of patients in the CAN group developed new posttransplantation anti-HLA antibodies compared with only 4% in the control group (P < 0.05). Overall, the results suggest that persistent cell-mediated and humoral alloimmunity contribute to the development of CAN and further demonstrate that anti-donor immunity in patients with CAN is heterogeneous. Immune monitoring to predict long-term outcome should include multiple measures of cellular and humoral immunity.     

Ultrastructural analysis of the Fisher to Lewis rat model of chronic allograft nephropathy

Chronic allograft nephropathy (CAN) is the leading cause of graft loss following kidney transplantation. One factor contributing to CAN is chronic alloimmune injury. However, the involvement of alloantigen-dependent and -independent factors in CAN is unclear. The pathomechanism of CAN has been extensively studied by utilizing the Fischer-to-Lewis (F344-to-LEW) rat model. Transplant capillaropathy (circumferential multiplication of the peritubular capillary basement membrane) and transplant glomerulopathy (reduplication of the glomerular basement membrane) have recently been validated clinicopathologically as ultrastructural indicators of chronic alloimmune injury. To investigate the presence of these markers, F344-to-LEW kidneys were examined by electron and light microscopy 32, 40 and 52 weeks after implantation. F344 rats with or without 30-min ischemia of the left kidney following right nephrectomy served as controls. All transplanted rats displayed marked proteinuria. On electron microscopy, transplant capillaropathy, transplant glomerulopathy, and T-cell cytotoxicity (indicator of ongoing cellular rejection) were absent. On light microscopy, the arteries were devoid of intimal fibrosis. Focal-segmental glomerulopathy resembling hyperfiltration injury was encountered, with mild interstitial infiltration, fibrosis, and tubular atrophy. The proteinuria and kidney pathology were more severe in transplanted than in ischemic or uninephrectomized rats. Because chronic-active rejection could not be detected between weeks 32 and 52, we propose that the alloantigen-dependent initial graft injury subsides, but induces the late events: glomerular hyperfiltration, proteinuria, and glomerulosclerosis. Accordingly, the model - in the late phase - is suitable to investigate alloantigen-independent factors of CAN and lacks markers of alloantigen-dependent processes.     

Peripheral nerve allograft: cellular and humoral immune responses of mice

Despite numerous experimental and clinical studies, no method has been established for achieving successful peripheral nerve allografts. One reason is that few studies concerning the immune response of the host have been conducted with nerve allografts. We therefore investigated the immune response of fresh nerve allografts with respect to both cellular and humoral immunological reactions. Using immunologically established strains of inbred mice, we performed the mixed lymphocyte culture (MLC) reaction and the cell-mediated lymphocytolysis reaction to test the cellular immune reaction and the complement-dependent cytotoxicity test to the humoral immune reaction. We observed that peripheral nerve tissues were strongly immunogenic; there was increased MLC reactivity to the allo-MHC antigen of the donor, specific cytotoxic T-cell activity, and production of specific antibody in the serum. For satisfactory nerve regeneration and transplantation, it is essential to suppress this immune response.     

Upregulation of connective tissue growth factor in a rat model of chronic allograft nephropathy

AIM: To study the expression of connective tissue growth factor (CTGF) in transplanted rat kidney and its relationship with chronic allograft nephropathy (CAN). METHODS: Kidney transplantation was performed from Lewis to Fisher 344 allogeneic rat strain, and kidney grafts were harvested at the eighth, 12th and 16th week. The morphological changes were studied, and collagen deposition was determined by Masson trichrome stain. Serum creatinine was examined. The fibrotic process and the CAN grades were evaluated according to Banff 97 schema. The expressions of transforming growth factor beta, CTGF and alpha-smooth muscle actin were detected to assess the development of grafted kidney fibrosis and to discuss their relationships. Spearman correlation was used for correlation study between CTGF expression and development of CAN. RESULTS: Serum creatinine was promoted in a time-dependent manner. Morphological changes suggested that the grafted kidneys were under abnormalities. At the end stage, focal segmental glomerulosclerosis was seen; tubular epithelial cells lost their phenotype and interstitial fibrosis was notable. Masson trichrome stain showed significant collagen accumulation in a time-dependent manner. Immunohistochemistry and western blotting results showed that the transforming growth factor beta, CTGF and alpha-smooth muscle actin expression were markedly promoted compared with the control group. CTGF was mainly expressed in the plasm of proximal tubular epithelial cells based on the severity of CAN. CONCLUSION: Connective tissue growth factor might play an important role in the pathological changes of CAN after kidney transplantation. The expression of CTGF in epithelial cells could act as a molecular marker of interstitial fibrosis and CAN.     

Conversion of ciclosporin A to tacrolimus in kidney transplant recipients with chronic allograft nephropathy.

BACKGROUND: Tacrolimus and ciclosporin might have different effects on intra-renal fibrosis and allograft function in chronic allograft nephropathy (CAN). It is difficult to predict the response to calcineurin inhibitor minimization in patients with CAN. METHODS: This prospective randomized study compared ciclosporin A (CsA)-to-tacrolimus conversion (group A, target tacrolimus trough level 6-8 ng/ml) vs CsA minimization (group B, target CsA trough level 80-100 ng/ml) with regard to efficacy and safety in patients with CAN and deteriorating allograft function. The primary efficacy endpoint was improvement in the slope of inverse serum creatinine (1/SCr) vs time plot. RESULTS: There were 34 evaluable patients (n=16 in group A; n=18 in group B), with similar baseline characteristics. Both groups reached target drug levels after a 3-month run-in period. Over the ensuing 12 months, nine (56.3%) subjects in group A and 10 (55.6%) in group B reached the primary end point (P=0.968). Both groups showed considerable improvement in the slope of 1/SCr vs time plot. There was no significant difference in the slope between groups before and after intervention. Graft survival was 87% in group A and 100% in group B (P=0.121). Acute rejection was encountered in two group A subjects. There was no significant change or difference in blood glucose, lipids, and blood pressure between groups. CONCLUSION: Our results suggest that in patients with CAN and deteriorating allograft function, CsA-to-tacrolimus conversion or CsA minimization achieved comparable efficacies in retarding the decline of graft function. Such contention may be biased by the low patient number. Further studies with a larger cohort are needed for validation.     

Cytomegalovirus accelerates chronic allograft nephropathy in a rat renal transplant model with associated provocative chemokine profiles

BACKGROUND: Studies have shown that rat cytomegalovirus (RCMV) infection accelerates transplant vascular sclerosis (TVS) in rat heart and small bowel allotransplants. In these models, RCMV-accelerated TVS results from increased graft infiltration of inflammatory cells through up-regulation of chemokine expression. The aim of this study was to determine if RCMV infection accelerates renal transplant chronic allograft nephropathy (CAN), and the role of chemokines in this process. METHODS: F344 kidneys were transplanted into Lewis recipients with and without RCMV infection. To monitor CAN, serum creatinine (Cr) levels were measured starting at 4 weeks posttransplantation. At 7 and 21 days, and at terminal rejection, grafts were examined for histologic changes, inflammatory cell infiltrates, viral load, and chemokine expression profiles. RESULTS: By week 8, serum Cr showed significant elevation (P < .01) in the RCMV-infected group vs uninfected group, and remained significantly elevated through the end of the study. RCMV+ renal allografts had significant inflammatory cell infiltration and increased CAN at postoperative day (POD) 28. The CC chemokines RANTES, MCP-1, and MIP-1alpha, and the CXC chemokine IP-10 were up-regulated in RCMV-infected vs uninfected allografts. IP-10 was significantly up-regulated early in the process, whereas RANTES and MCP-1 were induced at a later time. CONCLUSIONS: RCMV infection accelerates CAN, with associated graft inflammatory infiltrates, which is paralleled by an increase in expression of CC and CXC chemokines. Our findings suggest that the early induction of IP-10 in the infected allografts promotes alterations in T-cell and monocyte migration to the graft, which initiates accelerated inflammatory and fibrotic changes associated with CAN.     

The effect of FK778 on the progression of chronic allograft nephropathy in a rat model

BACKGROUND: Chronic allograft nephropathy (CAN) still belongs to the leading causes of graft loss over the long term. The leflunomide derivative FK778 is a novel immunosuppressant with improved pharmacokinetic properties that effectively prolonged graft survival in several transplantation models. In the present study, we investigated the effects of FK778 at different phases after transplantation on the progression of CAN. METHODS: Fisher 344 kidneys were orthotopically transplanted into Lewis recipients. Recipients were treated with FK778 (5 mg/kg/day) over different time periods (early: days 0-10 only, continuous: day 0 to week 24, or late: weeks 16-24 only posttransplantation). Proteinuria was measured every 4 weeks, whereas grafts were harvested at 24 weeks posttransplantation for morphological and immunohistochemical analysis as well as transforming growth factor-beta and platelet derived growth factor-B chain expression. RESULTS: Continuous treatment with FK778 ameliorated the progression of CAN, whereas late treatment reduced proteinuria and resulted in a similar grade of CAN as compared to animals with continuous treatment. In contrast, FK778 given only during the early phase after transplantation had no effect on the progression of CAN as compared to controls. CONCLUSION: In summary, FK778 is a potent immunosuppressive drug that can delay the progression of CAN, even when given at later stages after transplantation.     

大鼠供肾转染反义ERK2基因减缓肾移植后慢性移植肾肾病的作用及机制

目的 研究腺病毒介导的反义ERK2(A-dant-ERl(2)基因转染供肾对减缓肾移植后发生慢性移植肾肾病(CAN)的作用及机制.方法 建立大鼠间肾移植模型.按供肾移植前处理方式的不同分为对照组、空载病毒组和基因转染组,每组6只.对照组供肾灌注无菌HTK液0.5 ml,空载病毒组供肾灌注含5x109>pfu LaeZ基因腺病毒(Ad-LacZ)的HTK液0.5 ml,基因转染组供肾灌注含5x 109>pfu Adanti-ERK2的HTK液0.5 ml.肾移植术后24周行移植肾的病理学观察,免疫组织化学法观察肾小管上皮细胞表面标志蛋白E-Cadherin、Vimentin、TβRⅠ的表达以及CD4+、CD8+T淋巴细胞和ED-1+细胞的浸润情况;酶联免疫法检测受者血清中转化生长因子β1>(TGF-β1>)的含量.结果 肾移植术后24周,对照组和空载病毒组移植肾呈CAN表现;肾小球硬化,肾小管萎缩明显,伴严重间质纤维化以及明显的CD4+、CD8+T淋巴细胞和ED-1+细胞浸润;病变区肾小管上皮细胞E-Cadherin表达减少,Vimentin、TβRⅠ表达显著增多.基因转染组移植肾间质内仅有少量CD4+、CD8+T淋巴细胞和ED-1+细胞浸润;肾小管上皮细胞E-Cadherin表达正常.对照组和空载病毒组血清中TGF-β1>,含量明显高于基因转染组.结论 Adanti-ERK2基因转染移植肾可减缓CAN的发生,对移植肾具有保护作用.这种保护机制可能与减少炎症细胞的浸润、下调TGF-β1>,等致纤维化因子的表达以及抑制肾小管上皮细胞向间充质细胞的转化有关.     

Sirolimus attenuates chronic allograft nephropathy in an experimental rat kidney transplantation model

Chronic allograft nephropathy (CAN) is the primary reason for late allograft loss in kidney transplantation. The use of calcineurin inhibitors is suggested to be a risk factor for the development of CAN. Thus, calcineurin-inhibitor-free immunosuppressive protocols are needed to improve long-term graft outcome. Sirolimus affects the immune response by interfering with postreceptor interleukin-2 signaling. Safety profile of sirolimus is different from that of calcineurin inhibitors. We investigated the long-term effects of sirolimus on kidney allografts and fibrogenic growth factor expression and compared it to cyclosporine A. Kidney transplantations were performed from DA to WF rats and syngenic controls were done between DA rats. Allograft recipients were immunosuppressed daily with sirolimus 2 p.o. or CsA 1.5 mg/kg s.c. In addition, sirolimus-treated animals were treated with cyclosporine 1.5 mg/kg s.c. for the first 7 days after transplantation. Serum creatinine levels were measured once a week. Grafts were harvested 90 days after transplantation for histology and immunohistochemistry. Histological changes were scored according to the chronic allograft damage index (CADI). No signs of CAN were seen in syngenic grafts, CADI 0.8 +/- 0.2 (mean +/- SEM). In cyclosporine-treated allografts moderate to intense chronic changes were seen; CADI 10.3 +/- 0.6. Sirolimus significantly ameliorated the development of CAN compared to cyclosporine, CADI 3.0 +/- 0.5 (P < .05). Creatinine values of sirolimus-treated allografts were lower compared to the cyclosporine-treated allografts and were nearly similar to the syngenic grafts. Our results demonstrate that sirolimus attenuates the development of CAN and restores kidney function. Based on our findings, sirolimus improves the long-term kidney graft outcome.     

术前预处理及组织配型对高度致敏患者移植肾功能的影响

目的：探讨术前预处理及组织配型对高度致敏患者移植肾功能的影响。方法：对38例高度致敏患者(高敏组)肾移植术前进行预处理及组织配型,观察患者术后移植肾功能延迟(DGF)、排斥反应的发生和血肌酐(SCr)水平的变化。结果：高敏组术后发生超急性排斥反应(HAR)2例;其加速性排斥反应(ACR)、急性排斥反应(AR)以及DGF发生率均高于非高敏组受者,1年移植肾存活率则较低。高敏组中组织配型良好的受者较配型欠佳者AR发生率及术后1年SCr水平较低;术前预防性使用赛尼哌可降低术后的AR发生率。结论：预处理降低高度致敏患者群体反应性抗体(PRA),使患者易于配型成功,良好的组织配型和使用赛尼哌可降低术后AR的发生,均有助于移植肾功能的恢复。     

Prolonged cold ischemia accelerates cellular and humoral chronic rejection in a rat model of kidney allotransplantation

One of the leading causes of long-term kidney graft loss is chronic allograft injury (CAI), a pathological process triggered by alloantigen-dependent and alloantigen-independent factors. Alloantigen-independent factors, such as cold ischemia (CI) may amplify the recipient immune response against the graft. We investigated the impact of prolonged cold ischemia and the subsequent delayed graft function on CAI in a fully MHC-mismatched rat model of kidney allotransplantation. Prolonged CI was associated with anticipation of proteinuria onset and graft function deterioration (ischemia: 90d; no ischemia: 150d), more severe tubular atrophy, interstitial fibrosis, and glomerulosclerosis, and increased mortality rate (180d survival, ischemia: 0%; no ischemia: 67%). In ischemic allografts, T and B cells were detected very early and were organized in inflammatory clusters. Higher expression of BAFF-R and TACI within the ischemic allografts indicates that B cells are mature and activated. As a consequence of B cell activity, anti-donor antibodies, glomerular C4d and IgG deposition, important features of chronic humoral rejection, appeared earlier in ischemic than in non-ischemic allograft recipients. Thus, prolonged CI time plays a main role in CAI development by triggering acceleration of cellular and humoral reactions of chronic rejection. Limiting CI time should be considered as a main target in kidney transplantation.     

慢性移植肾肾病肾间质非特异性细胞浸润的意义

目的 探讨不同类型慢性移植肾肾病组织非特异性细胞浸润的意义及其预后.方法 回顾性分析2007年6月至2009年6月间83例肾移植受者的资料,受者均经移植肾穿刺证实为慢性移植肾肾病(CAN).按照Banff 2009标准,病例分为3组:慢性活动性T淋巴细胞介导的排斥反应(CTMR)组、慢性活动性抗体介导的排斥反应(CAMR)组和无特异性的间质纤维化和肾小管萎缩(NOS)组.检测并分析移植肾组织中肾小管和肾间质病变程度,CD4+、CD8+、CD20+和CD3+细胞浸润以及补体C4d染色情况.随访2年,记录移植肾存活率.结果 CTMR组受者为34例(40.9％),CAMR组为12例(14.6％),NOS组为37例(44.5％).3组间质炎症浸润范围、管周毛细血管炎和管周C4d沉积的差异均有统计学意义.CTMR组肾间质CD4+和CD8+细胞数高于CAMR组和NOS组.CTMR组移植肾存活率为73.5％,NOS组为78.4％,CAMR组为41.7％;CAMR组预后最差(P＜0.05).结论 CAMR预示肾功能预后不良,CD4+和CD8+细胞浸润是CTMR较特异性的指标,可能有助于CTMR的诊断.     

Effect of pentoxifylline on graft function of renal transplant recipients complicated with chronic allograft nephropathy

BACKGROUND: Chronic allograft nephropathy (CAN) is characterized by a progressive deterioration of renal function with various degrees ofproteinuria. Currently, there is no effective treatment despite the introduction of new generations of immunosuppressants. Pentoxifylline (PTX) is a phosphodiesterase inhibitor that possesses antiproteinuric effect and has been proved to be effective in treating several glomerular diseases. The purpose of the current study was to examine the effect of PTX on renal transplant patients with established CAN. MATERIALS AND METHODS: Renal transplant recipients with biopsyproven CAN were recruited for the study. All the patients had been on angiotensin-converting enzyme inhibitor or angiotensin receptor blocker for more than 1 year and were on a triple immunosuppressive regimen including corticosteroid, calcineurine inhibitor and mycophenolate mofetil. PTX in a dose of 1,200 mg/day was administered for at least 6 months. The following parameters were assessed at baseline, the 3rd and the 6th month post treatment: systolic and diastolic blood pressure, number of anti-hypertension drugs, serum creatinine (sCr),estimated glomerular filtration rate (eGFR), 24-hour urinary protein excretion (U/P), urinary N-acetylglucosaminidase (NAG) and intracytoplasmic Thl/Th2 cytokines production of peripheral blood CD4+ cells. RESULTS: A total of 17 (11 male and 6 female) patients were enrolled in the study. The mean duration of follow-up post transplant was 10.6+/- 4.4 years. The baseline data of sCr, eGFR and U/P were 1.83+/-0.46 mg/dl, 38+/-8 ml/min and 2.65+/-2.15 g/day, respectively. Corresponding values at the 3rd and 6th month post treatment were 1.90+/-0.43 mg/dl (p = NS), 33+/-7 ml/min (p=NS), 2.13 +/-1.13 g/day (p < 0.05) and 2.03+/-0.64 mg/dl (p < 0.05), 32+/-10 ml/min (p < 0.05), 2.74 +/-0.93 g/day (p = NS), respectively. When individual data were analyzed, five cases (29.4%) showed a U/P significant reduction of more than 50% of baseline value, while in 10 cases (58.8%) the graft function remained either stable (9 cases) or improved (1 case) at the end of treatment. Urinary NAG was elevated at the 3rd month, but stabilized thereafter. The Thl/Th2 intracytoplasmic cytokine pattern of peripheral blood CD4+ cells showed a significant decrease of cells bearing TNF-alpha (15.0+/-14.4% vs 14.2+/-17.0%, p < 0.05) and cells bearing IL-10 (1.60 +/-1.23% vs 0.90+/-0.66%, p < 0.05) at the 3rd month. CONCLUSION: In this pilot study, PTX seemed to be temporarily effective in reducing proteinuria. The graft function was stabilized in more than half of patients at the end of follow-up.     

益生注射液延缓大鼠慢性移植肾肾病的进程

目的　探讨中药益生注射液对大鼠慢性移植肾肾病(CAN)的防治效果。方法　分别采用封闭群雄性SD大鼠和Wistar大鼠作为供、受者进行原位肾移植,术中强化缺血再灌注损伤,建立CAN加快动物模型。将成模大鼠随机分为4个组,A组术后仅给予环孢素A(CsA)10 mg·kg-1·d-1治疗10 d;B、C组除接受CsA治疗外,还分别给予益生注射液4 mg/kg、8 mg/kg;D组除接受CsA治疗外,还给予霉酚酸酯(MMF)10 mg/kg。观察各组术后4、8及12周时的血肌酐水平、移植肾形态学变化及移植肾组织中转化生长因子β1(TGF β1)的表达。结果　术后4周起,A组的血肌酐水平明显高于其它三组(P<0.05);C组第12周时的血肌酐水平高于D组(P<0.05)。除A组术后12周出现TGF β1 表达下调外,各组术后TGF β1 的表达均呈上升趋势,A组4周和8 周时的表达最强;C组和D组的TGF β1 表达较弱。术后8周A组出现明显的CAN病理改变,而C组和D组出现明显血管内膜增生的时间明显晚于A组,且程度较轻。结论　中药益生注射液具有与霉酚酸酯类似的能够延缓慢性移植肾肾病进程的作用。     

铁调素在大鼠慢性移植肾肾病中的表达及其意义

目的 探讨铁调素(Hepcidin)在大鼠慢性移植肾肾病(CAN)动物模型中的表达变化及临床意义.方法 以F344近交系大鼠为供体、Lewis近交系大鼠为受体,原位肾移植,建立20只CAN大鼠模型;于模型建立术前、术后1、2及4个月分别收集大鼠的静脉血和尿样,检测肾功能;酶联免疫吸附法(ELISA)检测血清、尿Hepcidin、血清白细胞介素-6(IL-6)和促红细胞生成素(EPO)的表达;并于移植后2个月及4个月分别处死大鼠10只,观察各组大鼠移植肾组织病理学变化.结果 血清Hepcidin、IL-6表达随着移植术的时间逐渐增高,术前、术后1、2及4个月分别为(8.18±1.60)、(10.94±2.10)、(12.71 ±2.10)、(15.81±2.40) μg/L; (2.52±0.41)、(15.58 ±6.94)、(18.16±7.08)、(25.71 ±5.71) ng/L.尿Hepcidin排出逐渐减少,术前、术后l、2及4个月分别为(17.52±2.60)、(13.65 ±2.80)、(12.02±1.30)、(10.13 ±1.80) μg/L,EPO表达逐渐减少术前、术后1、2及4个月分别为(15.51 ±0.76)、(10.29 ±0.58)、(6.37 ±0.82)、(1.23±0.15) U/L,术前与术后比较差异有统计学意义(P＜0.05);移植术后大鼠血肌酐(Cr)、尿素氮(BUN)逐渐升高,并且Cr与血清Hepcidin呈正相关;移植术后血清Hepcidin的表达与IL-6呈正相关,与EPO呈负相关;肾脏病理形态、HE染色符合CAN的病理改变.结论 随着移植肾功能的减退,大鼠体内微炎性反应增加,Hepcidin在大鼠CAN模型表达变化与肾功能有关.Hepcidin随着时间和炎症状态表达的变化可反映肾功能损伤.     

Presensitization accelerates chronic allograft rejection in a heterotopic rat tracheal allograft model with immunosuppression

BACKGROUND: In the field of organ transplantation, the effect of pretransplant humoral allosensitization on the organ transplant outcome has been highlighted. To clarify the correlation of presensitization with chronic rejection that can lead to a poor prognosis in transplant recipients, we examined humoral alloreactivity and allograft rejection in sensitized recipients by using a rat heterotopic tracheal transplant model. METHODS: An MHC fully incompatible combination strain was used in this study. Lewis (LEW) rats sensitized by transplantation with Brown Norway (BN) skin grafts received tracheal segments from BN rats in the dorsal subcutaneous pouch. Four allogenic groups (n=5) were investigated. Group 1, non-sensitized recipients without cyclosporine A (CsA) administration; group 2, non-sensitized recipients with CsA administration; group 3, sensitized recipients without CsA administration; and group 4, sensitized recipients with CsA administration. In the immunosuppressant groups (groups 2 and 4), the recipients were administered a subcutaneous injection of CsA (25 mg x kg(-1) x day(-1)) for 3 days from the day of operation. All recipients were sacrificed 21 days after transplantation. Tracheal segments were extracted from the recipients and histologically evaluated with regard to the following parameters: (1) airway lining epithelial loss, (2) lymphocyte/plasma cell infiltration, and (3) luminal obliteration due to granulation tissue formation and/or fibrosis. In order to analyze alloantibody (allo-Ab) responses, sera samples were tested by the flow cytometric cross-match (FCXM) technique. RESULTS: Histological findings revealed that the chronic rejection score in sensitized recipients treated with CsA was significantly higher than that in non-sensitized recipients treated with CsA (9.0+/-1.2 vs. 3.0+/-0.54, p<0.05). In other words, CsA therapy reduced the rejection score in non-sensitized recipients, but not in sensitized recipients. No significant differences were observed in the level of IgM Abs among the groups. However, donor-specific IgG Abs were induced after presensitization by donor skin grafting prior to tracheal transplantation. Heterotopic tracheal implantation also induced IgG Ab production. This elevation in the Ab levels was inhibited by CsA treatment in non-sensitized recipients. Conversely, the Ab levels were significantly higher in sensitized recipients than in non-sensitized recipients, regardless of CsA administration. CONCLUSIONS: Our data showed that presensitization accelerates chronic allograft rejection with a marked elevation in the level of donor specific IgG Abs. These results suggest that presensitization will be a significant risk factor for the lung transplant recipient, furthermore, the effect of immunosuppression might be insufficient in sensitized recipients.