Determination of mismatched donor HLA in kidney transplant recipients with unknown donor HLA phenotypes

Kwok J, Chan GSW, Lam MF, Yan T, Tang L, Kwong KM, Chan KW, Chan TM. Determination of mismatched donor HLA in kidney transplant recipients with unknown donor HLA phenotypes.
Clin Transplant 2010 DOI: 10.1111/j.1399‐0012.2010.01246.x
© 2010 John Wiley & Sons A/S. Abstract: Objective: To determine donor human leukocyte antigen (HLA) from renal allograft biopsies in transplant recipients whose donor HLA phenotype is not known. Methods: Renal allograft biopsies were obtained from seven renal transplant recipients when indicated for allograft dysfunction or proteinuria. DNA was extracted fresh from allograft specimens, and HLA typing was performed with polymerase chain reaction‐specific sequence primers (PCR‐SSP) and polymerase chain reaction‐sequence‐specific oligonucleotides (PCR‐SSO). Results: HLA typing of the seven renal allograft biopsies was composed of both recipient and donor HLA phenotypes, allowing the determination of the donor HLA and the degree of HLA mismatching. Conclusions: Deducing mismatched donor HLA antigens in renal allograft recipients enables detection of donor‐specific antibodies, and the management of humoral rejection, and enables more appropriate selection of a donor organ should future retransplantation be required.     

扩大供肾标准的亲属肾移植临床效果分析

目的 探讨扩大供肾标准的亲属肾移植临床效果.方法 回顾性分析2005年11月至2011年6月亲属活体肾移植274例的临床资料,按供者情况分为扩大供者标准(供者年龄≥60岁、肾脏解剖结构/功能异常)组(66例)和标准供者组(208例).扩大标准组供者年龄≥60岁36例,其中合并肾囊肿6例,合并肾结石1例;肾囊肿22例,囊肿直径4～40 mm;肾结石4例,结石直径3 ～～6 mm;术侧肾小球滤过率(GFR) ＜35 ml/min 4例.统计学比较两组受者术后3、7d,l、3、6、12个月血清SCr值、并发症发生率、急性排斥反应发生率、移植肾功能延迟恢复(DGF)发生率,1、3年人/肾存活率.结果 扩大标准组及标准供者组受者术后3、7d血清SCr值分别为(242.7±132.2)、( 185.6±148.4) μmol/L和(156.7±86.8)、( 122.2±136.8) μmol/L,两组受者第3天与第7天SCr值比较差异均有统计学意义(P＜0.05);但两组受者术后1、3、6、12个月血SCr、并发症发生率、急性排斥反应发生率、DGF发生率,1、3年人/肾存活率之间比较差异均无统计学意义(P＞0.05).结论 ≥60岁健康高龄、直径＜40 mm供肾囊肿仍可考虑作为亲属肾移植供者;低GFR应结合供者年龄、供受者体表面积比、供受者体质量比、可通过外科处理纠正等方面综合考虑;供肾结石者应慎重选择.     

Necrotizing glomerulonephritis in a living donor kidney transplant recipient

The occurrence of a rapidly progressive necrotizing glomerulonephritis after kidney transplantation is exceptional and usually leads to graft failure. We describe a case of necrotizing glomerulonephritis that developed 5 months after renal transplantation in a patient suffering from prolonged bowel paralysis and sepsis. After reinforcement of corticosteroid therapy and introduction of cyclophosphamide, glomerulonephritis recovered. Cyclophosphamide was stopped after 2 months and replaced by azatioprine while prednisone was progressively reduced. Three years after transplantation the patient has a stable serum creatinine of 1.7 mg/dL and mild proteinuria. To the best of our knowledge this is the first case of recovery from a necrotizing glomerulonephritis in a renal transplant recipient.     

简单条件下大鼠肾移植模型的建立

目的探讨在简单条件下,稳定的、用于移植后早期免疫功能等实验研究的大鼠肾移植模型的建立方法。方法以Wistar大鼠为供体,Sprague Dawley大鼠为受体。取供体大鼠左肾,移植物包括与肾静脉相连的下腔静脉段,与肾动脉相连的腹主动脉段,以及与输尿管相连的供体膀胱瓣,经腹主动脉原位低温灌注6～8mL4℃肝素生理盐水。受体手术于裸眼下完成,供体下腔静脉与受体下腔静脉、供体腹主动脉与受体腹主动脉行端侧吻合,供体输尿管带膀胱瓣与受体膀胱两定点连续缝合。结果共完成50例异体肾移植大鼠模型,存活41例,手术成功率82%,存活时间（6.3±1.6）d。供体手术时间（44.8±7.4）min、受体手术时间（59.0±6.6）min、动脉吻合时间（15.9±2.3）min、静脉吻合时间（14.2±2.7）min、尿路重建时间（5.3±0.8）min、热缺血时间（55.7±4.5）s和冷缺血时间（55.1±5.9）min。结论建立此模型所需要的实验条件简单,术者容易掌握,移植成功率高。     

Living related donor kidney grafts in the cyclosporine era

The results of 120 LRD kidney grafts, 49 HLA identical and 71 haploidentical, performed between 1981 and 1987 during the CyA era have been analyzed. The reduction in the incidence of rejection in diploidenticals with CyA vs AZA did not increase short- or long-term graft survival but was accompanied by worse kidney function and a greater need for antihypertensives. CyA did improve the results in haploidentical recipients over our historical experience, although prior sensitization was still a major hazard in this group.     

大鼠肾移植模型建立研究进展

大鼠肾移植实验模型建立显微外科以及分析移植相关方面的研究有着其重要的意义.随着临床肾移植的不断发展,以及对于器官移植排斥反应研究的重视,大鼠肾移植模型愈来愈受到人们的关注,本文对于大鼠肾移植模型建立研究进展综述如下.     

Early experience of a living donor kidney transplant program

OBJECTIVES: Laparoscopic nephrectomy has been shown to reduce the morbidity of live donor nephrectomy, but post-transplant kidney function and safety issues with the procedure are still of some concern. The review of our early experience could detect errors that should be avoided in the refining of the technique. METHODS: Our first sixty consecutive laparoscopic donor nephrectomies were analyzed retrospectively. RESULTS: There were conversions to open surgery (5%), all three in the first 18 cases. All donors were alive at 1 year with a glomerular filtration rate of 85+/-21 ml/min (78% of the basal). Patient and graft survival at 1 year was 100% and 95%, respectively. Creatinine nadir was achieved on post-transplant day 3 (creatinine, 176+/-122 micromol/l). Late renal function proved a continuous improvement until the 2-year follow-up (creatinine, 135+/-29 micromol/l). Renal function recovery was better in both recipient and donor when the donor was < or =50 years old, compared with older patients. Transplant complications that required reintervention included one ureteral fistula, one ureteral stenosis and one case of low renal flow that was re-vascularised. CONCLUSIONS: Technical surgical aspects such the use of Haemoloc clips in the clipping of the artery, the hand-assisted extraction of the kidney, a refined surgical technique during the transplant and avoidance of prolonged warm and cold ischemia, taken together with an adequate intraoperative hemodynamic management of the donor aid in avoiding life-threatening complications and achieving a good post-transplant renal function recovery.     

Hyperlipidemia in pediatric kidney transplant recipients treated with cyclosporine

Hyperlipidemia is a risk factor for cardiovascular disease in adult kidney transplant (Tx) recipients. We sought to determine the prevalence of, and the risk factors associated with, hyperlipidemia in pediatric kidney Tx recipients on cyclosporine (CsA). We identified 59 patients (mean age 8.2+/-5.7 years) transplanted between 1 January 1991 and 31 December 1993. Pre Tx, 34% had elevated total cholesterol [TC >200 mg/dl (5.17 mmol/l)]; 54% had elevated triglycerides [TG >200 mg/dl (2.26 mmol/L)]. Mean TG was higher pre Tx in dialysis (versus nondialysis) patients: 306 mg/dl (3.46 mmol/l) versus 228 mg/dl (2.58 mmol/l) ( P=0.04). Mean TC was higher in peritoneal dialysis than hemodialysis patients: 222 mg/dl (5.74 mmol/l) versus 169 mg/dl (4.37 mmol/l) ( P=0.03). Pre Tx and 3-year values correlated (TC, r=0.49, P=0.0008; TG, r=0.41, P=0.001); 3- and 5-year TC values correlated ( r=0.57, P=0.003). At 5 years post Tx, 41% of the recipients had elevated TC; 14% had elevated TG. Recipients with elevated TC had higher mean CsA concentrations at 1 year post Tx ( P=0.03). Recipients with elevated TG tended to receive more prednisone ( P=0.06). At 5 years post Tx, recipients had a high prevalence of hyperlipidemia. The identification and treatment of hyperlipidemia should be included in pediatric kidney Tx protocols.     

Rejection of a kidney transplant does not always lead to priming of cytotoxic T cells against mismatched donor HLA class I antigens

BACKGROUND: Previous studies showed that graft rejection is often associated with the presence of primed cytotoxic T cells (CTLs) with a high avidity for donor cells. Similar high avidity CTLs have been found in individuals who have formed IgG anti-HLA antibodies. The presence of such CTLs to a specific HLA mismatch is therefore considered to be a reflection of an activated immune system, and a contraindication for retransplantation with a donor sharing this particular HLA class I mismatch. METHODS: In our study we investigated whether patients have always primed CTLs against all individual HLA class I mismatches present on a rejected graft. Therefore, 14 patients who had undergone transplantectomy after irreversible kidney graft rejection were analyzed with respect to donor-specific CTLp frequencies and the presence or absence of high avidity CTLs directed against HLA class I mismatches present on the rejected graft. RESULTS: Patients, who have not formed anti-HLA antibodies against the donor have mainly naive CTLs. Most of the patients, that have developed IgG anti-HLA antibodies against a donor mismatch, have primed CTLs directed against that particular mismatch. However, patients with IgM anti-HLA antibodies only, and patients with IgG anti-HLA antibodies in historical sera but no IgG anti-HLA antibodies in current sera, have mainly naive CTLs against the donor HLA mismatch. CONCLUSION: Our results suggest that it is not always necessary to exclude repeated HLA class I mismatches for a subsequent transplantation. In addition to good anti-HLA antibody screening, the CTLp-assay may be a useful tool for donor-selection in retransplant candidates.     

Nephrotoxicity of cyclosporine A and cyclosporine G in a rat model

Cyclosporine G (CsG) like cyclosporine A (CsA) is a cyclic endecapeptide where the alpha-amino butyric acid residue in position 2 is replaced by norvaline. We studied the effects of both drugs on renal function in a nontransplant rat model to avoid the additional variable of rejection. Age- and weight-matched pairs of male Sprague-Dawley rats were treated subcutaneously for 21 days with a daily dose of 25 mg/kg bw of either powdered CsA or CsG dissolved in 1 ml of olive oil. A control group (C) received olive oil only. Blood pressure (BP) and creatinine (Cr) were measured on days 0, 7, 14, and 21. On day 22, animals were weighed, anesthetized, and glomerular filtration rate (GFR) and renal plasma flow (RPF) were measured using c14 inulin and 3H paraAminohippuric acid, respectively. Renal plasma flow and glomerular filtration rate were unaltered in CsG-treated animals compared to controls but significantly reduced in CsA-treated animals. Histologically, vacuolization and microcalcification were seen in significantly greater frequency among the CsA-treated animals. CsG with lesser nephrotoxic potential may prove to be of use in maintenance of therapy of transplants as well as selected autoimmune disorders.     

Low-dose immunosuppression in a rat hind-limb transplantation model

Composite tissue allografts (CTAs) offer an alternative to conventional reconstructive methods. However, the toxicity of the drugs that are required to prevent rejection has prevented its widespread clinical application. The purpose of this study was to determine whether a low-dose, corticosteroid-free combination regimen of tacrolimus and mycophenolate mofetil (MMF) would prevent rejection in a rat hind-limb model, with minimal toxic side effects. Three groups were used in this study. In group I, Wistar Furth (WF) rats received a syngeneic WF hind-limb. In groups II and III, WF rats received an ACI hind-limb. The latter were treated with tacrolimus–MMF. Assessment for rejection, flow cytometry, and mixed lymphocyte reactions was performed. Biopsies were taken regularly and at the time of killing. Combination therapy with low-dose tacrolimus–MMF effectively prolonged CTA survival indefinitely, with minimal side effects. Toxicity associated with immunosuppressive drugs can be avoided in a low-dose combination corticosteroid-free regimen.     

Low-dose immunosuppression in a rat hind-limb transplantation model

Composite tissue allografts (CTAs) offer an alternative to conventional reconstructive methods. However, the toxicity of the drugs that are required to prevent rejection has prevented its widespread clinical application. The purpose of this study was to determine whether a low-dose, corticosteroid-free combination regimen of tacrolimus and mycophenolate mofetil (MMF) would prevent rejection in a rat hind-limb model, with minimal toxic side effects. Three groups were used in this study. In group I, Wistar Furth (WF) rats received a syngeneic WF hind-limb. In groups II and III, WF rats received an ACI hind-limb. The latter were treated with tacrolimus-MMF. Assessment for rejection, flow cytometry, and mixed lymphocyte reactions was performed. Biopsies were taken regularly and at the time of killing. Combination therapy with low-dose tacrolimus-MMF effectively prolonged CTA survival indefinitely, with minimal side effects. Toxicity associated with immunosuppressive drugs can be avoided in a low-dose combination corticosteroid-free regimen.     

Prolongation of allograft survival by repeated cycles of donor antigen and cyclosporine in rat kidney transplantation

Combination therapy with a short course of cyclosporine (CsA) on the day prior to, to day of, and the day after transplantation and one dose of 5 mg 3M-KCl-extracted donor-soluble antigen (Ag) prolongs the survival of Buffalo (Buf, RT1b) kidney allografts in Wistar-Furth (WFu, RTu) inbred rats because of the induction of specific suppressor cells. Four systems were utilized to demonstrate suppressor cell activity in vivo. First, pooled lymphocytes from CsA-Ag-treated hosts suppressed the capacity of admixed, syngeneic WFu cells to display an in vivo mixed lymphocyte culture reaction toward donor Buf, but not third-party Brown-Norway (BN, RT1n), hosts. Second, systemic adoptive transfer two days prior to, or on the day of, transplantation of 5 x 10(8) putative suppressor cells harvested ten days after combined Ag-CsA treatment prolonged graft survival slightly but significantly from 7 to 9 days in virgin, secondary hosts. Third, admixture of 5 x 10(8) cells from Ag-CsA-treated hosts vitiated the capacity of 5 x 10(8) virgin WFu spleen cells to restore the capacity of recipients sublethally irradiated with 500 rads to reject. Buf allografts at 7.9 days rather than 16.7 days. Fourth, i.p. administration of low-dose cyclosphophamide (CY) 7 days after transplantation, a regimen known to inhibit suppressor cells, reduced the capacity of the Ag-CsA regimen to prolong graft survival. Two additional cycles of CsA therapy at 10-day intervals administered in an attempt to maintain T suppressor dominance over T helper cells prolonged median graft survival to 65 days. Similar prolongation was not achieved using donor blood transfusion as the immunogen, or using cycles of CsA alone. These findings suggest that 3M KCl donor antigen amplifies the induction of specific suppressor cells, and that CsA by virtue of helper T cell inhibition facilitates the establishment of suppressor cell dominance, eventually leading to host unresponsiveness.