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Background: Kidney transplant recipients (KTRs) with "operational tolerance" (OT) maintain a functioning graft without immunosuppressive (IS) drugs, thus avoiding treatment complications. Nevertheless, IS drugs can influence gene-expression signatures aiming to identify OT among treated KTRs., Methods: We compared five published signatures of OT in peripheral blood samples from 18 tolerant, 183 stable, and 34 chronic rejector KTRs, using gene-expression levels with and without adjustment for IS drugs and regularised logistic regression., Findings: IS drugs explained up to 50% of the variability in gene-expression and 20-30% of the variability in the probability of OT predicted by signatures without drug adjustment. We present a parsimonious consensus gene-set to identify OT, derived from joint analysis of IS-drug-adjusted expression of five published signature gene-sets. This signature, including CD40, CTLA4, HSD11B1, IGKV4-1, MZB1, NR3C2, and RAB40C genes, showed an area under the curve 0⋅92 (95% confidence interval 0⋅88-0⋅94) in cross-validation and 0⋅97 (0⋅93-1⋅00) in six months follow-up samples., Interpretation: We advocate including adjustment for IS drug therapy in the development stage of gene-expression signatures of OT to reduce the risk of capturing features of treatment, which could be lost following IS drug minimisation or withdrawal. Our signature, however, would require further validation in an independent dataset and a biomarker-led trial., Funding: FP7-HEALTH-2012-INNOVATION-1 [305147:BIO-DrIM] (SC,IR-M,PM,DSt); MRC [G0801537/ID:88245] (MPH-F); MRC [MR/J006742/1] (IR-M); Guy's&StThomas' Charity [R080530]&[R090782]; CONICYT-Bicentennial-Becas-Chile (EN-L); EU:FP7/2007-2013 [HEALTH-F5-2010-260687: The ONE Study] (MPH-F); Czech Ministry of Health [NV19-06-00031] (OV); NIHR-BRC Guy's&StThomas' NHS Foundation Trust and KCL (SC); UK Clinical Research Networks [portfolio:7521]., Competing Interests: Declaration of Competing Interest Dr. Christakoudi reports grants from FP7-HEALTH-2012-INNOVATION-1 (project number 305147: BIO-DrIM), grants from National Institute for Health Research (NIHR) Biomedical Research Centre based at Guy's and St Thomas' NHS Foundation Trust and King's College London, during the conduct of the study. Mr. Runglall has nothing to disclose. Dr. Mobillo reports grants from FP7-HEALTH-2012-INNOVATION-1 (project number 305147: BIO-DrIM), during the conduct of the study. Dr. Rebollo-Mesa reports grants from [MR/J006742/1] to MRC Centre for Transplantation, grants from FP7-HEALTH-2012-INNOVATION-1 (project number 305147: BIO-DrIM), during the conduct of the study; other from UCB Pharma SRL, outside the submitted work. Mr. Tsui has nothing to disclose. Dr. Nova-Lamperti reports grants from CONICYT Bicentennial-Becas-Chile scholarship, during the conduct of the study. Dr. Taube has nothing to disclose. Dr. Norris has nothing to disclose. Mr. Kamra has nothing to disclose. Dr. Hilton reports personal fees from Chiesi Ltd, outside the submitted work. Dr. Augustine has nothing to disclose. Dr. Bhandari has nothing to disclose. Dr. Baker has nothing to disclose. Dr. Berglund has nothing to disclose. Dr. Carr has nothing to disclose. Dr. Game reports personal fees from Advisory board Chiesi pharmaceuticals, personal fees from Advisory board Recordati Rare Diseases, personal fees from Advisory board Syneos Health, outside the submitted work. Dr. Griffin has nothing to disclose. Dr. Kalra has nothing to disclose. Dr. Lewis has nothing to disclose. Dr. Mark reports personal fees and non-financial support from Vifor, personal fees from Astrazeneca, grants from Boehringer Ingelheim, personal fees and non-financial support from Pharmacosmos, personal fees from Janssen, personal fees from Novartis, personal fees from Pfizer, personal fees from Bristol Myers Squibb, personal fees and non-financial support from Napp, outside the submitted work. Dr. Marks has nothing to disclose. Dr. MacPhee reports other from AstraZeneca, other from AstraZeneca, grants and personal fees from Chiesi, personal fees from Astellas, personal fees from Sandoz, outside the submitted work. Dr. McKane has nothing to disclose. Dr. Mohaupt has nothing to disclose. Dr. Paz-Artal has nothing to disclose. Dr. Kon has nothing to disclose. Dr. Seron has nothing to disclose. Dr. Sinha has nothing to disclose. Dr. Tucker has nothing to disclose. Prof. Viklicky reports grants from CZECH MINISTRY OF HEALTH, during the conduct of the study. Dr. Stahl reports grants from FP7-HEALTH-2012-INNOVATION-1 (project number 305147: BIO-DrIM), during the conduct of the study. Dr. Lechler has nothing to disclose. Dr. Lord has nothing to disclose. Dr. Hernandez-Fuentes reports grants from FP7-HEALTH-2012-INNOVATION-1 (project number 305147: BIO-DrIM), grants from Medical Research Council MRC grants to Maria P. Hernandez-Fuentes [G0801537/ID: 88245], grants from Guy's and St Thomas’ Charity [grants R080530 and R090782], grants from EU; FP7/2007–2013], under grant agreement [No HEALTH-F5–2010–260687: The ONE Study], grants and non-financial support from National Institute for Health Research (NIHR) Biomedical Research Centre based at Guy's and St Thomas' NHS Foundation Trust and King's College London, non-financial support from Clinical Research Networks [study portfolio number 7521], during the conduct of the study; other from UCB Celltech., outside the submitted work; ., (Copyright © 2020 The Authors. Published by Elsevier B.V. All rights reserved.)

Background: Two large, prospective studies (12-03; OSAKA) compared the efficacy and tolerability of prolonged-release versus immediate-release tacrolimus in kidney transplant patients also receiving mycophenolate mofetil and low-dose corticosteroids (without induction therapy)., Methods: Data were combined into one database to compare results over 24 weeks using 3 alternative endpoints: biopsy-confirmed acute rejection (BCAR); the Food and Drug Administration composite endpoint (graft loss, BCAR, and loss to follow-up), and the European Medicines Agency composite endpoint (graft loss, BCAR, and graft dysfunction). The 95% confidence intervals were calculated (10% noninferiority margin)., Results: Overall, 633 patients received prolonged-release tacrolimus (12-03, n = 331; OSAKA, n = 302) and 645 received immediate-release tacrolimus (n = 336; n = 309). Baseline characteristics were comparable. Proportionately more patients receiving prolonged-release tacrolimus had trough levels of 5-15 ng/mL on day 1 (60.8%) and 2 (56.6%) versus immediate-release tacrolimus (42.5% and 43.9%, respectively, both P < .001). Efficacy of prolonged-release and immediate-release tacrolimus were similar as assessed by BCAR (13.9% vs 14.1%, respectively), European Medicines Agency composite endpoint (40.3% vs 38.3%) and US Food and Drug Administration composite endpoint (21.5% vs 19.8%)., Conclusions: Novel efficacy endpoints as required by the European Medicines Agency and US Food and Drug Administration demonstrate noninferiority of prolonged-release versus immediate-release tacrolimus. Significantly more patients treated with prolonged-release tacrolimus versus immediate-release tacrolimus achieved trough levels of 5 to 15 ng/mL early after transplantation. ClinicalTrials.govNCT00189839; NCT00717470., (Copyright © 2017 Elsevier Inc. All rights reserved.)

We and others have previously described signatures of tolerance in kidney transplantation showing the differential expression of B cell-related genes and the relative expansions of B cell subsets. However, in all of these studies, the index group-namely, the tolerant recipients-were not receiving immunosuppression (IS) treatment, unlike the rest of the comparator groups. We aimed to assess the confounding effect of these regimens and develop a novel IS-independent signature of tolerance. Analyzing gene expression in three independent kidney transplant patient cohorts (232 recipients and 14 tolerant patients), we have established that the expression of the previously reported signature was biased by IS regimens, which also influenced transitional B cells. We have defined and validated a new gene expression signature that is independent of drug effects and also differentiates tolerant patients from healthy controls (cross-validated area under the receiver operating characteristic curve [AUC] = 0.81). In a prospective cohort, we have demonstrated that the new signature remained stable before and after steroid withdrawal. In addition, we report on a validated and highly accurate gene expression signature that can be reliably used to identify patients suitable for IS reduction (approximately 12% of stable patients), irrespective of the IS drugs they are receiving. Only a similar approach will make the conduct of pilot clinical trials for IS minimization safe and hence allow critical improvements in kidney posttransplant management., (© 2016 The Authors. American Journal of Transplantation published by Wiley Periodicals, Inc. on behalf of American Society of Transplant Surgeons.)

Aims: To determine the incidence of malignancies in renal transplant recipients (RTRs) and to analyze the association between the risk of skin cancer and immunosuppressive regiments used in the posttransplant period., Materials and Methods: A cohort study was performed on 797 RTRs. Standardized morbidity ratio (SMR) was calculated for the most common types of cancer developed in the posttransplant period and different types of immunosuppressive therapy used in the cohort., Results: 192 cases of malignancies were diagnosed in 86 RTRs (10.8%). Nonmelanoma skin cancer (NMSC) was the most frequent type of cancer (SMR = 6.42, p = 0.000), followed by renal cancer (SMR = 5.9, p = 0.000), malignant melanoma (SMR = 2.59, p = 0.080), and prostate cancer (SMR = 1.21, p = 0.593). The risk to develop NMSC was significantly higher in the group where cyclosporine has been used besides tacrolimus, mycophenolatemophetil and steroids as well as in the group treated with the combination without cyclosporine (SMR = 9.62, p = 0.001 and SMR = 5.18, p = 0.000). Furthermore, the risk was significantly higher in RTRs receiving anti-thymocyte globulin within induction therapy (SMR = 4.14, p = 0.000)., Conclusion: The preliminary results indicate that the risk of NMSC in RTRs is significantly higher than in the general population and thus emphasize the need to improve preventive strategies in the Czech transplant population., (© 2016 Wiley Periodicals, Inc.)

To ensure safety tolerance induction protocols are accompanied by conventional immunosuppressive drugs (IS). But IS such as calcineurin inhibitors (CNI), for example, cyclosporin A (CsA), can interfere with tolerance induction. We investigated the effect of an additional transient CsA treatment on anti-CD4mAb-induced tolerance induction upon rat kidney transplantation. Additional CsA treatment induced deteriorated graft function, resulting in chronic rejection characterized by glomerulosclerosis, interstitial fibrosis, tubular atrophy and vascular changes. Microarray analysis revealed enhanced intragraft expression of the B cell attracting chemokine CXCL13 early during CsA treatment. Increase in CXCL13 expression is accompanied by enhanced B cell infiltration with local and systemic IgG production and C3d deposition as early as 5 days upon CsA withdrawal. Adding different CNIs to cultures of primary mesangial cells isolated from glomeruli resulted in a concentration-dependent increase in CXCL13 transcription. CsA in synergy with TNF-α can enhance the B cell attracting and activating potential of mesangial cells. Transient B cell depletion or transfer of splenocytes from tolerant recipients 3 weeks after transplantation could rescue tolerance induction and did inhibit intragraft B cell accumulation, alloantibody production and ameliorate chronic rejection., (© Copyright 2013 The American Society of Transplantation and the American Society of Transplant Surgeons.)

Renal transplantation represents a method of choice in irreversible renal failure. The outcome of renal transplantation is affected by acute or chronic rejection and long-term evaluation also suggest a role of adverse effects of immunosuppressive therapy, mainly the incidence of cardiovascular complications and tumours. Immunosuppressive therapy with biologic agents aims to reduce the incidence of acute rejections, prolong allograft survival and, consequently, patient survival. Apart from a reduction in acute rejection incidence, biological agents are used in a selected group of patients to eliminate the need for an adjunctive treatment with steroids and to reduce consequences of ischemic-reperfusion damage in older donors who suffer from a range ofco-morbidities. The most frequently used therapies include induction and anti-rejection therapy with a rabbit polyclonal anti-human thymocyte globulin (rATG) or an induction therapy with monoclonal anti-interleukin-2 receptor antibody (anti-IL2R), basiliximab. Considering the high immunosuppressive effect of rATG, adverse effects, mainly opportunistic infections and more frequent delayed tumourigenesis, have to be taken into account.

Renal ischaemia/reperfusion (I/R) injury and hypertension represent major alloantigen-independent risk factors contributing to the development of chronic allograft nephropathy. In a model of accelerated major histocompatibility complex-independent renal injury, we evaluated the effect of leflunomide derivate - FK778 - on the progression of accelerated nephropathy. Thirty-six uninephrectomized hypertensive transgenic (m-REN-2)-27 rats received a clip on renal pedicle for 45 minutes. Animals were treated with FK778 3 mg/kg/day (I/R 3 mg, N = 12), 10 mg/kg/day (I/R 10 mg, N = 12) or placebo (N = 12) via gavage for 16 weeks. Eighteen animals were sham-operated and treated with FK778 3 mg/kg/day (sham 3 mg, N = 6), 10 mg/kg/day (sham 10 mg, N = 6) or were untreated (sham, N = 6). Proteinuria and blood pressure were evaluated throughout and the kidneys were harvested for morphological and immunohistochemical analysis at the end of the experiment. At week 16, rats with I/R injury and FK778 treatment had lower proteinuria compared with placebo-treated rats (I/R 3 mg: 48.42 +/- 26.16, I/R 10 mg 27.28 +/- 21.86 vs. Placebo: 70.13 +/- 50.19 mg/day, P < 0.05). The untreated sham group exhibited lower proteinuria compared with FK778-treated sham groups (Sham 3 mg: 24.23 +/- 10.89; Sham 10 mg: 17.37 +/- 4.13; Sham: 14.23 +/- 1.18) There was no difference in glomerulosclerosis and interstitial fibrosis among the treated groups. In the untreated animals the rate of interstitial fibrosis decline reached statistical significance (Placebo vs. Sham: 1.125 +/- 0.641 % vs. 0.250 +/- 0.500 %, P < 0.05). There was higher CD5+ leukocyte infiltration in the placebotreated group. FK778-treated rats displayed amelioration of some changes induced by the I/R injury. Our observation also suggests potential nephrotoxicity of FK778.

Background: Renal ischemia and hypertension have been suggested to be involved in the progression of renal diseases. Recently, we developed a model of accelerated major histocompatibility complex-independent renal injury, where high-renin hypertension aggravates functional and morphological changes induced by ischemia/reperfusion (I/R). In this model, we evaluated the effect of immunosuppressant mycophenolate mofetil (MMF) to test its capability to slow the progression of accelerated nephropathy., Methods: 34 anesthetized uninephrectomized hypertensive transgenic (mREN2)27 rats (TGR) received a clamp on the renal pedicle for 45 min. Animals were treated with MMF 10 mg/kg/day (n = 10), 20 mg/kg/day (n = 10) or placebo (n = 10) orally via gavage for 12 weeks. Four animals were sham operated and not treated. Proteinuria and blood pressure were evaluated throughout the experiment. At the end of the experiment, kidney function was evaluated and kidneys harvested for morphological analysis and immunohistochemistry (CD4+, CD8+ lymphocytes and specific rat monocyte/macrophage marker ED-1+ cells)., Results: At week 12, both MMF-treated groups had lower proteinuria as compared to the placebo group (MMF 10: 22.4 +/- 9.8, MMF 20: 20.9 +/- 5.6 vs. 126.7 +/- 35.8; p < 0.01; sham 28.1 +/- 1.4 mg/day) and reduced glomerulosclerosis (MMF 10: 11.4 +/- 7.8, MMF 20: 5.2 +/- 2.7 vs. 20.9 +/- 10.9; p < 0.05; sham 15.7 +/- 9.2%). There were no differences in systolic blood pressure among groups. MMF-treated rats had lower CD4+ (MMF 10: 61.2 +/- 46.4, MMF 20: 29.3 +/- 18.2 vs. 125.3 +/- 42.8; p < 0.01, sham 84.9 +/- 6.1 cells/field of view) and CD8+ (MMF 10: 13.7 +/- 10.2, MMF 20: 10.0 +/- 8.1 vs. 37.8 +/- 14.3; p < 0.01; sham: 31.8 +/- 7.6 cells/field of view) lymphocytes infiltration and ED-1 macrophages infiltration (MMF 10: 5.5 +/- 6.4, MMF 20: 2.5 +/- 2.8 vs. 16.7 +/- 4.1; p < 0.01; sham 12.2 +/- 4.6 cells/field of view) than placebo-treated rats., Conclusion: Our results thus support the hypothesis about the key role of immune mechanisms in progression of chronic nephropathies., (Copyright 2006 S. Karger AG, Basel.)

Transforming growth factor (TGF)-beta1 is a key profibrogenic cytokine associated with the pathogenesis of chronic allograft nephropathy (CAN). The primary aim of this study was to evaluate TGF-beta1 expression in protocol kidney graft biopsy in patients treated with different immunosuppressive regimens. Protocol kidney graft biopsies were carried out in 77 patients with stable graft function at 1 year after kidney transplantation, treated with a triple-drug regimen based on cyclosporin A (CyA; n = 49) or tacrolimus (TAC; n = 28). Morphological findings were assessed using the Banff 97 classification. TGF-beta1 expression was analysed using immunochemistry, and semiquantitatively scored in different renal structures (total score 0-18). Clinical data were analysed at the time of biopsy, and 12 months thereafter. No significant relation was found between the used immunosuppressive regimen and the histomorphological picture in the graft. TGF-beta1 expression within graft tissue was significantly higher in patients treated with CyA when compared with TAC (9.94 +/- 4.2 vs. 5.0 +/- 3.2; P < 0.001). Serum creatinine and glomerular filtration rate (GFR; Cockroft-Gault calculation) were comparable in both groups but, in the course of the next 12 months, GFR significantly decreased only in the CyA-treated group (from 1.03 +/- 0.33 to 0.96 +/- 0.37 ml/s) while not changing in the TAC-treated group. Patients treated with TAC had significantly lower diastolic blood pressure and serum cholesterol. The significantly lower TGF-beta1 expression in 1-year protocol kidney graft biopsy in TAC-treated patients with stable renal function, and the different development of graft function in both groups suggest a possible benefit of TAC for long-term graft acceptance.

The etiology of chronic glomerulopathies is not yet clear, however the impairment of immune system is supposed to play a decisive role. Thus, immunosuppressants are often used to slow the activity and/or progression of the disease. Usually the patients are treated either by corticosteroids alone or by the combination of corticosteroids with other immunosuppressive agents. Recently, immunosuppressants successfully applied in the transplantation medicine have been also tested in the therapy of chronic glomerulopathies. Cyclosporine A, a potent calcineurin inhibitor, has been used as a second line therapy. The place of CsA in lupus nephritis and especially in IgA nephropathy is not defined so well as it is in idiopathic nephrotic syndrome. The newer calcineurin inhibitor tacrolimus is already widely used in the transplantation medicine while its effectiveness in clinical nephrology has to be tested. Mycophenolate mofetil in monotherapy or with concomitant low-dose steroids can be regarded as an alternative therapeutical approach in case of standard regimens' failure. Sirolimus just entered clinical transplant medicine and its role in slowing the progression of chronic glomerulopathies is not yet clear.

Chronic rejection represents the most common cause of transplanted graft loss in the long term. Rapamycin (sirolimus), and it's derivate RAD, are new and potent, immunosuppressive drugs. They inhibit cell proliferation driven by various growth factors. These drugs were successfully tested in some experimental models of the chronic rejection. Results of the first clinical trials have defined rapamycin pharmacokinetics and proved immunosuppressive efficacy. Rapamycin acts synergistically with cyclosporin A. The side effects are a dose-dependent thrombocytopenia and leukopenia but the most frequent is hyperlipidemia. The question, if rapamycin and RAD inhibit development of chronic rejection in man, will be solved by the prospective clinical trials over years.

Chronic rejection is the major cause of graft loss after kidney transplantation. Various immunosuppressive protocols have been used to ameliorate this process. We investigated whether cyclosporin A- (CyA) or azathioprine- (Aza) based immunosuppression is better able to slow the progression of chronic rejection. Fisher kidneys were transplanted into bilaterally nephrectomized Lewis rats. Recipients received CyA (1.5 mg/kg/day, s.c.) for 10 days, and were treated from day 11 with either CyA (1.5 mg/kg)+pred (0.15 mg/kg) (C+P),Aza (2 mg/kg)+pred (A+P), vehicle+pred (P), or vehicle alone (controls) (n = 8/group). Proteinuria was regularly assessed and grafts were harvested for morphological, immunohistological, and molecular biological analysis at week 24. By week 12 proteinuria had increased to significant levels. At week 24, proteinuria was significantly lower and creatinine clearance was significantly higher in C+P and A+P, than in P or controls. Morphological analysis supported these functional results: at week 24, glomerulopathy, tubular atrophy and intimal proliferation (as assessed according to the BANFF score) were less pronounced in C+P and A+P, as compared with P or controls. These morphological parameters were accompanied by a reduced infiltration of ED-1+ macrophages and CD-5+ T lymphocytes. In P or controls the synthesis of IL-2Ralpha mRNA was markedly elevated at this time. In parallel to the reduced cellular infiltration, IL-2Ralpha mRNA expression was markedly inhibited, both, in C+P and A+P. There were no significant differences between C+P and A+P regarding the parameters studied. In conclusion, both C+P and A+P reduced the infiltration of activated T lymphocytes, and the pace of chronic kidney allograft rejection. The outcome of C+P and A+P based therapy did not differ significantly.

Background: Chronic rejection remains the most frequent cause of renal graft loss over the long term. However, effective treatment of this process is not yet available. SDZ-RAD (40-O-[2-hydroxyethyl]-rapamycin) is a new, orally active rapamycin derivative with potent immunosuppressive activity. We have examined the effects of SDZ-RAD in a well-established model of chronic renal allograft rejection in rats., Methods: Kidneys of Fisher (F334) rats were orthotopically transplanted into bilaterally nephrectomized Lewis recipients. To suppress an initial episode of acute rejection, rats were briefly treated with low doses of cyclosporine for the first 10 days. Thereafter they received either SDZ-RAD (0.5 mg/kg(day) or vehicle. At 24 weeks, functional evaluations were performed, kidneys were harvested, and histological, immunohistological, and reverse transcription-polymerase chain reaction evaluations were performed., Results: Animals treated with SDZ-RAD developed lower proteinuria and less glomerulosclerosis as compared with controls. Additionally SDZ-RAD reduced the infiltration of macrophages and lymphocytes and the expression of intercellular adhesion molecule-1, laminin, and fibronectin. Furthermore, we observed a reduced expression of growth factor mRNA (transforming growth factor-beta and platelet-derived growth factor-AA) in these animals., Conclusion: Our results demonstrated that SDZ-RAD effectively ameliorates chronic renal allograft rejection in rats, probably mediated by suppression of growth factors.

The authors compared in a controlled clinical study two groups of patients after a first renal transplantation treated by triple drug immunosuppressive therapy. In a group of 31 patients the triple combination comprised Sandimmune Neoral. In the control group there were 30 patients who received Sandimmune. No differences were found between the two groups as regards the effectiveness of this treatment and the authors did not confirm a lower incidence of rejections described in patients treated with Sandimmune Neoral. They confirmed, however, a lower interindividual variability of Cy-A levels assessed specifically in patients treated with Sandimmune Neoral.

The purpose of this systematic review and meta-analysis was to compare the risk of non-melanoma skin cancer (NMSC) and melanoma development in renal transplant recipients who receive calcineurin inhibitors to that of patients treated with other immunosuppressive agents, and investigate the possible association between the type of maintenance immunosuppression and the incidence of NSMC and melanoma in this group of patients. The authors searched databases such as PubMed, Scopus, and Web of Science for articles that would help establish the influence of calcineurin inhibitors on skin cancer development. The inclusion criteria for the study consisted of randomized clinical trials, cohort studies, and case-control studies that compared patients who received kidney transplants and were treated with a calcineurin inhibitor (CNI), such as cyclosporine A (CsA) or tacrolimus (Tac), to those who received alternative immunosuppressants and did not receive a CNI. Seven articles were analyzed overall. The results revealed a correlation between CNI treatment in renal transplant recipients and increased total skin cancer risk (OR 1.28; 95% CI: 0.10–16.28; p < 0.01), melanoma risk (OR 1.09; 95% CI: 0.25–4.74; p < 0.01), and NMSC risk (OR 1.16; 95% CI: 0.41–3.26; p < 0.01). In conclusion, the calcineurin inhibitors used after kidney transplantation are associated with a higher risk of skin cancer—both non-melanoma and melanoma—when compared with other immunosuppressive therapies. This finding suggests that careful monitoring for skin lesions in post-transplant patients must be conducted. However, the decision on the kind of immunotherapy used should always be considered on an individual basis for each renal transplant recipient. [ABSTRACT FROM AUTHOR]