Cardiac retransplantation: is it justified in times of critical donor organ shortage? Long-term single-center experience

Objective: Survival after heart transplantation has improved significantly over the last decades. There are a growing number of patients that require cardiac retransplantation because of chronic allograft dysfunction. With regard to the critical shortage of cardiac allograft donors the decision to offer repeat heart transplantation must be carefully considered. Methods: Since 1983 a total of 807 heart transplantations have been performed at our institution. Among them 41 patients received cardiac retransplantation, 18 patients because of acute graft failure and 23 because of chronic graft failure. Data were analyzed for demographics, morbidity and risk factors for mortality. The acute and chronic retransplant group was compared to those patients undergoing primary transplantation. Results: The mean interval between primary transplantation and retransplantation was 1.9 days in the acute and 6.7 years in the chronic retransplant group. Mean follow-up was 6.9 years. Baseline characteristics were similar in the primary and retransplant group. Actuarial survival rates at 1, 3, 5 and 7 years after primary cardiac transplantation compared to retransplantation were 83, 78, 72 and 64% vs 53, 50, 47 and 36%, respectively (p < 0.001). Early mortality after acute retransplantation was significantly higher compared to late retransplantation (10/18, 55.6% vs 4/23, 17.4%, p = 0.011). Major causes of death were acute and chronic rejection, infection and sepsis. Conclusions: Cardiac retransplantation is associated with lower survival rates compared to primary transplantation. However, results after retransplantation in chronic graft failure are significantly better compared to acute graft failure. Therefore, we consider cardiac retransplantation in chronic graft failure a justified therapeutic option. In contrast, patients with acute graft failure seem to be inappropriate candidates for cardiac retransplantation.     

Retransplantation in 7,290 primary transplant patients: a 10-year multi-institutional study.

BACKGROUND: Cardiac retransplantation is a controversial procedure due to the disparity between donor heart demand and supply. METHODS: Of 7,290 patients undergoing primary cardiac transplantation between January 1990 and December 1999 at 42 institutions contributing to the Cardiac Transplant Research Database (CTRD), 106 patients later underwent a second and 1 patient a third cardiac transplant procedure. RESULTS: The actuarial freedom from retransplantation was 99.2% and 96.8% at 1 and 10 years, respectively. Reasons for retransplantation included early graft failure (n = 34), acute cardiac rejection (n = 15), coronary allograft vasculopathy (CAV, n = 39), non-specific graft failure (n = 7), and miscellaneous (n = 10). The only risk factor associated with retransplantation was younger age, reflecting the policy of preferential retransplantation of younger patients. Survival after retransplantation was inferior to that after primary transplantation (56% and 38% at 1 and 5 years, respectively). Risk factors associated with death after retransplantation included retransplantation for acute rejection (p = 0.0005), retransplantation for early graft failure (p = 0.03), and use of a female donor (p = 0.005). Survival after retransplantation for acute rejection was poorest (32% and 8% at 1 and 5 years, respectively) followed by retransplantation for early graft failure (50% and 39% at 1 and 5 years, respectively). Survival after retransplantation for CAV has steadily improved with successive eras. CONCLUSIONS: The results of retransplantation for acute rejection and early graft failure are poor enough to suggest that this option is not advisable. However, retransplantation for CAV is currently associated with satisfactory survival and should continue to be offered to selected patients.     

The results of cardiac retransplantation: an analysis of the Joint International Society for Heart and Lung Transplantation/United Network for Organ Sharing Thoracic Registry

BACKGROUND: It is well established that repeat heart transplantation has a significantly worse outcome when compared with primary (first time) transplantation. Defining the risk factors for mortality within this group has been difficult due to small numbers of patients at individual centers. METHODS: All cardiac retransplants performed in the United States and registered in the Joint International Society for Heart and Lung Transplantation (ISHLT)/United Network for Organ Sharing (UNOS) Thoracic Registry were analyzed for demographics, morbidity posttransplantation, immunosuppression, and risk factors for mortality. RESULTS: The study cohort included 514 patients of which 81% were male with a mean age of 47+/-12 years. Time from primary transplant to retransplantation ranged from 1 day to 15.5 years and more than 50% of the patients underwent retransplantation for chronic rejection. More than 60% of patients were in the intensive care unit at the time of retransplantation and more than 40% of the patients were reported to be on some form of life support (ventricular assist device, ventilator, and/or inotropic therapy). Survival for the entire retransplant cohort was 65, 59, and 55% for 1, 2, and 3 years, respectively, but was substantially lower when the intertransplant interval was short. Conversely, when the interval between primary and retransplantation was more than 2 years, 1 year survival postretransplantation approached that of primary transplantation. Additional independent risk factors for mortality for the retransplant cohort included overall cardiac transplant center volume, the use of a ventricular assist device or ventilator, the patient being in the intensive care unit, and recipient age. The four most common causes of death were infection, primary/nonspecific graft failure, chronic rejection (allograft vasculopathy), and acute rejection. CONCLUSIONS: The data confirm that repeat heart transplantation is a higher risk procedure than primary transplantation, especially early after the primary heart transplant.     

Right ventricular failure following heart transplantation--recovery after extended mechanical support

Abstract   Early graft failure, particularly right ventricular dysfunction, remains a significant determinant of early morbidity and mortality in heart transplant recipients. If conservative medical management fails to help recover cardiac allograft function, mechanical circulatory support either bridging to recovery or retransplantation remains the last option. We report on a 16-year-old patient with hypertropic nonobstructive cardiomyopathy who was weaned successfully from a right ventricular assist device (RVAD) after extended right ventricular mechanical support for three months following heart transplantation.     

Gene Expression Profiling for Monitoring Graft Rejection in Heart Transplant Recipients

Heart transplantation is a life-prolonging therapy for many patients with stage D heart failure and other forms of advanced heart disease. However, graft rejection and/or immunosuppression-related side effects are major causes of morbidity and death among heart transplant patients. Graft rejection monitoring remains a challenge. It would be desirable to be able to detect rejection early enough and specifically enough to prevent allograft dysfunction without unnecessary overimmunosuppression. Hitherto, the main technique employed in monitoring the rejection status of a transplanted heart has been endomyocardial biopsy (EMB), which allows rejection to be screened for and monitored on the basis of the extent and distribution of lymphocytic infiltrates and associated myocardial damage. However, EMB has significant limitations: it is invasive, its sensitivity is limited by sampling efficacy, and it suffers from considerable between-observer variability. Although many noninvasive techniques have been investigated, none so far has proved able to match the performance of EMB. Currently, a multiparametric approach is employed that comprises clinical examination for signs or symptoms of heart failure, EMBs, drug level monitoring, allograft function tests (mainly echocardiographic studies), and screening for allograft vasculopathy. Gene expression profiling may be a promising tool for this purpose.     

Outcomes for pediatric liver retransplantation from living donors

BACKGROUND: The only therapeutic option for patients with a failing allograft is retransplantation. Living donor liver transplantation (LDLT) is a well-accepted therapeutic option for end-stage liver disease, but retransplantation from a living donor (Re-LDLT) has not previously been discussed. METHODS: A total of 547 LDLTs were performed in 519 children (<18 years old) at Kyoto University Hospital from June 1990 to October 2002. During the same study period, a total of 28 Re-LDLTs were performed in 27 recipients (Re-LDLT performed twice in 1 patient). Patient survival was analyzed with respect to various preoperative factors, such as functional status, pretransplantation apheresis, cause of primary graft failure, interval from primary to subsequent transplants, and laboratory values of total bilirubin and creatinine. RESULTS: Kaplan-Meier survival rate from the date of Re-LDLT to 1 year was 47.6%. Functional status, pretransplantation apheresis, interval to Re-LDLT, and bilirubin and creatinine levels all exerted an adverse impact on survival after Re-LDLT. Pathologically proven major causes of primary graft failure were chronic rejection (n=10, 35.7%), chronic cholangitis (n=6, 21.4%), and vascular complications (n=7, 25.0%). Among these causes, vascular complications displayed the strongest adverse impact on survival, compared with chronic cholangitis and chronic rejection (1-year survival was 35.7% in vascular complications; 66.7% in chronic cholangitis; and 60.0% in chronic rejection). CONCLUSIONS: Re-LDLT can save patients with a failing allograft. To achieve better results after Re-LDLT, further investigations are necessary to understand the factors leading to poor outcome after Re-LDLT.     

Early and late outcomes after cardiac retransplantation

Background

Cardiac retransplantation remains the most viable option for patients with allograft heart failure; however, careful patient selection is paramount considering limited allograft resources. We analyzed clinical outcomes following retransplantation in an academic, tertiary care institution.

Methods

Between 1981 and 2011, 593 heart transplantations, including 22 retransplantations were performed at our institution. We analyzed the preoperative demographic characteristics, cause of allograft loss, short- and long-term surgical outcomes and cause of death among patients who had cardiac retransplantations.

Results

Twenty-two patients underwent retransplantation: 10 for graft vascular disease, 7 for acute rejection and 5 for primary graft failure. Mean age at retransplantation was 43 (standard deviation [SD] 15) years; 6 patients were women. Thirteen patients were critically ill preoperatively, requiring inotropes and/or mechanical support. The median interval between primary and retransplantation was 2.2 (range 0–16) years. Thirty-day mortality was 31.8%, and conditional (> 30 d) 1-, 5- and 10-year survival after retransplantation were 93%, 79% and 59%, respectively. A diagnosis of allograft vasculopathy (p = 0.008) and an interval between primary and retransplantation greater than 1 year (p = 0.016) had a significantly favourable impact on 30-day mortality. The median and mean survival after retransplantation were 3.3 and 5 (SD 6, range 0–18) years, respectively; graft vascular disease and multiorgan failure were the most common causes of death.

Conclusion

Long-term outcomes for primary and retransplantation are similar if patients survive the 30-day postoperative period. Retransplantation within 1 year of the primary transplantation resulted in a high perioperative mortality and thus may be a contraindication to retransplantation.     

Intractable recurrent hepatitis A virus infection requiring repeated liver transplantation: a case report

Although hepatitis A virus (HAV) infection is usually self-limited, it may induce fulminant hepatitis. We present an unusual case of a 40-year-old, otherwise healthy man with intractable recurrent HAV infection requiring retransplantation after primary liver transplantation for HAV-associated fulminant liver failure. After the first living-donor liver transplantation, allograft function recovered uneventfully; however, beginning at 35 days, his serum total bilirubin concentration increased, reaching 40 mg/dL, with a slight increase in liver enzymes. Detection of genomic HAV RNA in serum at the time of graft dysfunction led to a diagnosis of recurrent HAV infection. Fifty-one days after the first transplant, he underwent a deceased donor retransplantation. His allograft function recovered; the patient was discharged from the hospital. Sixty-five days later, however, he was readmitted for colitis-like symptoms and was again treated for acute rejection, but died owing to overwhelming sepsis and persistence of HAV infection. These findings indicate that patients who undergo liver transplantation for HAV-associated liver disease may be at risk of HAV reinfection, particularly if they require anti-rejection therapy. Routine measurements of anti-HAV immunoglobulin M and HAV RNA during the early posttransplant period in HAV-associated liver transplant recipients may differentiate reinfection from an acute cellular rejection episode.     

Retransplant and Medical Therapy for Cardiac Allograft Vasculopathy: International Society for Heart and Lung Transplantation Registry Analysis

Cardiac retransplantation for heart transplant recipients with advanced cardiac allograft vasculopathy (CAV) remains controversial. The International Society for Heart and Lung Transplantation Registry was used to examine survival in adult heart recipients with CAV who were retransplanted (ReTx) or managed medically (MM). Recipients transplanted between 1995 and 2010 who developed CAV and were either retransplanted within 2 years of CAV diagnosis (ReTx) or alive at ≥2 years after CAV diagnosis, managed medically (MM), without retransplant, constituted the study groups. Donor, recipient, transplant characteristics and long‐term survival were compared. The population included 65 patients in ReTx and 4530 in MM. During a median follow‐up of 4 years, there were 24 deaths in ReTx, and 1466 in MM. Survival was comparable at 9 years (55% in ReTx and 51% in MM; p = 0.88). Subgroup comparison suggested survival benefit for retransplant versus MM in patients who developed systolic graft dysfunction. Adjusted predictors for 2‐year mortality were diagnosis of CAV in the early era and longer time since CAV diagnosis following primary transplant. Retransplant was not an independent predictor in the model. Challenges associated with retransplantation as well as improved CAV treatment options support the current consensus recommendation limiting retransplant to highly selected patients with CAV.     

Hepatitis C, acute humoral rejection, and renal allograft survival

The effect of recipient hepatitis C virus (HCV) infection on renal allograft loss and acute rejection in kidney transplantation remains controversial. We studied 354 renal allograft recipients transplanted during 1996 to 2001 who had HCV antibodies (Ab) measured before transplantation. The primary outcome was death-censored allograft loss and the secondary outcome was acute humoral rejection (AHR). Compared with HCV Ab-negative patients, those with positive HCV Ab had longer time on dialysis before transplantation, higher percentage of panel-reactive antibodies (PRA), were more likely to receive a cadaveric transplant, and were more likely to develop delayed graft function (DGF). In univariate analyses, predictors of renal allograft loss included HCV, cadaveric graft, PRA >20%, HLA mismatch > or =5, retransplantation, DGF, induction therapy, and AHR. When adjusted for PRA >20%, HLA mismatch > or =5, and multiple transplant status, HCV was not a statistically significant predictor of allograft loss. HCV was also associated with AHR but lost significance when adjusted for PRA >20%. HCV Ab-positive patients were more likely to have longer duration of dialysis before transplantation prior to kidney transplants, higher PRA, and to receive cadaveric transplants. These characteristics likely resulted in more DGF and AHR after transplantation. After adjusting for these confounding factors, the association between HCV Ab positivity and renal allograft loss was notably attenuated and no longer statistically significant.     

Long-term survival after cardiac retransplantation: a twenty-year single-center experience

OBJECTIVE: To identify risk factors for survival after cardiac retransplantation and compare the survival after retransplantation with that after primary cardiac transplantation. METHODS: A retrospective analysis of 952 patients undergoing cardiac transplantation for the treatment of end-stage heart disease at a single center between 1977 and October 1997. Of these, 43 patients (4.5%) underwent cardiac retransplantation for cardiac failure resulting from transplant-related coronary artery disease, rejection, and early graft failure. RESULTS: No significant difference in actuarial patient survival was found by Kaplan-Meier analysis at 1, 2, and 5 years between patients undergoing primary transplantation and those undergoing retransplantation 76%, 71%, and 60% versus 66%, 66%, and 51%, respectively (P =.2). Multivariable analysis identified a shorter interval between transplants and an initial diagnosis of ischemic cardiomyopathy as significant risk factors for death after retransplantation (P =.04 and.03, respectively). Since 1993, when our criteria for patient selection for retransplantation were revised on the basis of earlier experience to exclude patients with allograft dysfunction as a result of primary graft failure and those with intractable acute rejection occurring less than 6 months after transplantation, the survival has been significantly better (<1993 = 45%, 45%, and 33% versus >/=1993 = 94%, 94%, and 94% at 1, 2, and 4 years, respectively, P =.003). CONCLUSION: The long-term outcome of cardiac retransplantation is comparable with that of primary transplantation, especially in patients with transplant-related coronary artery disease. Patient characteristics and other preoperative variables should assist in the rational application of retransplantation to ensure optimal use of donor organs.     

The association of viral infection and chronic allograft nephropathy with graft dysfunction after renal transplantation

BACKGROUND: The long-term effect of viral infections on graft dysfunction and rejection after renal transplantation is uncertain. METHODS: A cohort of 37 renal transplant recipients was followed prospectively for 3 years. Creatinine clearance rate at 6 months and 3 years and chronic allograft nephropathy were correlated with the detection of cytomegalovirus (CMV), human herpesvirus 6 and human herpesvirus 7 and BK virus DNA, CMV disease, and acute rejection. RESULTS: CMV disease was significantly associated with poor graft function at 6 months, whereas chronic allograft nephropathy was associated with graft dysfunction at 3 years. Both CMV disease and detection of human herpesvirus 6 DNA were associated with chronic allograft nephropathy. CONCLUSIONS: CMV disease was a significant cause of early graft dysfunction, whereas the presence of chronic allograft nephropathy was the main determinant of poor long-term graft function. The role of viral infections in chronic allograft nephropathy deserves further investigation.     

A single-center study of the technical aspects and outcome of third and subsequent renal transplants

BACKGROUND: Third, fourth, and fifth renal transplants are historically associated with poor outcomes. The reasons for these inferior results are unclear. In the current work, we analyzed the outcome of third and subsequent transplants and determined whether technical failure accounted for significant allograft loss. METHODS: The outcome and operative details of 49 transplants performed in 38 patients from a single center were reviewed. Thirty-eight patients received a third transplant, nine patients received a fourth transplant, and two patients received a fifth transplant. RESULTS: Actuarial patient survival was 100% and 97% at 5 and 10 years, respectively. One- and 5-year actuarial graft survival for third transplants was 90% and 62%, respectively, and for fourth transplants, 67% and 55%, respectively. Technical failure accounted for the loss of 2 third allografts and for no fourth or fifth allografts. Of the remaining third grafts, 12 failed as the result of chronic allograft nephropathy, and one failed as the result of recurrent membranoproliferative glomerulonephritis (type I). Of the fourth allografts, one failed as the result of acute rejection, two failed as the result of chronic allograft nephropathy, and one failed as the result of primary nonfunction. The mean graft survival of third and fourth transplants after a biopsy-proven acute rejection episode requiring steroid boost was significantly reduced. Of the fifth transplants, one graft failed as the result of hyperacute rejection, and one patient died with a functioning graft. Favorable human leukocyte antigen matching and a panel-reactive antibody less than 80% provided no statistical benefit to graft survival. CONCLUSIONS: The major cause of graft loss of third and fourth renal transplants is immune mediated. Although technically demanding, surgical failure is an unusual cause of graft loss.     

Results of retransplantation in individuals who received two successive cadaver kidneys.

At the Royal Victoria Hospital in Montreal, 22 patients received two successive cadaver renal transplants. The results were analysed to determine which factors have the best predictive value for success or failure in renal retransplantation. The fate of a second cadaver renal allograft was found to be about the same as the first if the initial transplant has been lost because of rejection and not technical failure. The duration of survival of the initial transplant serves as the best guide to potential outcome of retransplantation after rejection of the initial graft.     

Management of the Patient with a Failed Renal Transplant

The management of the failed renal transplant depends upon the clinical circumstances. In most instances of failure secondary to acute rejection or structural lesions, transplant nephrectomy is necessary. When failure is due to chronic rejection, grafts often can be left in place and removed only for the indications of fever, pain, swelling, infection, or refractory hypertension. Once dialysis has been reinstituted, immunosuppression should be tapered in accordance with standard principles; this often does not result in the need to remove the failed allograft so long as it is clinically quiet. The presence of a nonfunctioning graft does not preclude retransplantation. With the use of cyclosporine, the results of retransplantation are beginning to look similar to the statistics for first transplants. The quality of life in patients who have failed transplantation has not been definitely proven to be worse than that of patients on dialysis or those who have a functioning graft. However, patients with a failed transplant will need emotional support in their readjustment to dialysis.     

Successful retransplantation after renal allograft loss to polyoma virus interstitial nephritis

BACKGROUND: Although polyoma virus infection is being increasingly recognized as a cause of renal allograft dysfunction and failure, the risk of polyoma recurrence in a subsequent transplant is unknown. We present the first reported case of successful retransplantation after polyoma virus-induced renal allograft loss. CASE REPORT: A 40-year-old Caucasian woman received a cadaveric kidney transplant. Baseline immunosuppression included corticosteroids, mycophenolate mofetil, and tacrolimus. Her post-transplant clinical course was complicated by an early acute rejection episode on posttransplant day (PTD) 6, that warranted treatment with OKT3. A biopsy performed on PTD 154 to evaluate a rise in creatinine revealed polyoma virus interstitial nephritis. Despite reduction in immunosuppression, the renal function progressively worsened and dialysis was initiated by PTD 160, followed by transplant nephrectomy on PTD 184. Four months later, she received a living related kidney from her sister. Immunosuppression was initiated with prednisone, azathioprine, and tacrolimus. She had immediate graft function with a decrease in serum creatinine from 12.8 to 1.1 mg/dl. Three and one-half years after her second renal transplant, her allograft functions well, with a serum creatinine of 1 mg/dl. Both quantitative and qualitative assays of blood and urine (by PCR) remain negative for BK virus, indicating the absence of virus reactivation. CONCLUSION: Judicious retransplantation should be considered as a therapeutic option in the management of polyoma virus induced graft failure. Previous graft loss secondary to polyoma virus infection is not a contraindication to retransplantation.     

Impact of temporary mechanical circulatory support for early graft failure on post–heart transplantation outcomes

Although temporary mechanical circulatory support (tMCS) for hemodynamic failure following heart transplantation is associated with increased early morbidity and mortality, the impact of etiology of graft dysfunction and long-term clinical implications are less well known. The objective of our study was to evaluate outcomes in patients who required venoarterial extracorporeal membrane oxygenation (VA ECMO) or temporary right ventricular assist device (RVAD) support for either primary or secondary early graft dysfunction. Hospital mortality in 27 patients who required tMCS following heart transplantation at our institution between 2007 and 2017 was 56%, 30% in patients with right ventricular dysfunction secondary to increased afterload, 60% in patients with primary graft dysfunction, and 100% in patients with graft failure secondary to coagulopathy with intraoperative bleeding or overwhelming sepsis. Conditional 1-year and 5-year survival was comparable between patients with, and without, the need for post-transplantation support with tMCS (98% and 89%; 92% and 65% at 1 and 5 years, P = .21). Etiology of early graft failure plays an important part in determining the short-term post–heart transplantation outcome. Although complications associated with tMCS use, such as renal dysfunction and infection, extend beyond index transplant hospitalization, long-term conditional survival is not compromised.     

Chronic rejection in renal transplantation

Chronic rejection in renal transplantation is an alloantigen-dependent immune process ultimately leading to graft failure. We reviewed the literature on the basis of the case history of a patient who lost her renal allograft apparently from chronic interstitial rejection. Chronic rejection presents clinically as chronic transplant dysfunction starting at various intervals after transplantation. The histopathologic features consist of chronic allograft nephropathy with or without transplant vasculopathy or glomerulopathy. Chronic rejection should be differentiated from chronic toxicity of calcineurin inhibitors, de novo or recurrent glomerulonephritis, polyoma (BK) virus nephropathy, transplant renal artery stenosis, and nephrosclerosis. Young recipient age, black race, presensitization, histoincompatibility, and acute, especially vascular, and late acute rejection episodes are dominant risk factors, compatible with immunologic mechanisms. Cellular and humoral responses resulting from indirect recognition of alloantigens with subsequent fibrotic sequelae play a central role in the pathogenesis. Circulating donor-specific antibodies and staining for C4d can detect humoral chronic rejection. The prognosis depends on alloreactivity and the presence of progression factors such as old donor age, renal dysfunction, proteinuria, hyperlipidemia, and smoking. A multifactorial approach directed to the risk and progression factors is needed to prevent premature graft loss from chronic rejection.     

再次肝移植22例的指征与疗效分析

目的 分析我院再次肝移植患者的手术指征和移植效果.方法 2001年6月至2004年11月,22例患者因各种原因行再次肝移植.原因分别为：胆道并发症10例,肝动脉血栓形成4例,其中1例合并胆漏,慢性排斥反应4例,急性排斥反应2例,原发性移植肝无功能2例.并对再次肝移植患者进行随访.结果 在22例再次移植患者中,存活12例,死亡10例,住院期间死亡率为45%（10/22）.死亡病例术后生存时间3～35 d,平均12.6 d.死于脓毒败血症7例;手术出血性休克2例;脑血管意外1例.在存活者中,并发症发生率为25%（3/12）,其中胆道并发症2例,伤口裂开1例,院内感染11例,感染率为92%（11/12）.随访2～28个月,中位随访时间18个月.存活3～31个月,中位生存时间为16个月.结论 再次肝移植主要指征为胆道并发症、肝动脉栓塞、慢性及急性排斥反应,原发性移植肝无功能.导致再次肝移植死亡原因主要为脓毒败血症.     

Donor antigen-specific regulatory T-cell function affects outcome in kidney transplant recipients

Chronic transplant dysfunction, a major impediment to long-term allograft survival, is caused by several factors including an ongoing alloimmune response termed chronic rejection. To define some of these factors further, we selected 107 patients mismatched to their donors from 623 patients transplanted at a single center. Patients were categorized according to their immunosuppressive treatment and further divided into those with stable or chronic allograft dysfunction. Donor human lymphocyte antigen allopeptide-specific T-cell lines were then generated from stable patients and those with biopsy-proven chronic allograft nephropathy. Increased amounts of CD4+CD25+ regulatory T cells (Tregs) and Treg-associated gene expression profiles were found in cell lines derived from the patients with stable compared with those with chronic allograft dysfunction. Furthermore, a higher percentage of Tregs was found in patients with stable graft function on tacrolimus-based compared with cyclosporine-based immunosuppression protocols. Patients with stable graft function had a significantly higher expression of interleukin (IL)-4 and IL-10, whereas the cytokines IL-2, IL-17, and interferon-γ were significantly higher in patients with allograft dysfunction in vitro. Thus, enhancing the operational role of naturally occurring donor-specific Tregs in allograft recipients by adjusting the immunosuppression protocol may be advantageous particularly for patients with ongoing chronic rejection.