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Alemtuzumab induction is associated with decreased hospitalization rates in pediatric kidney transplant: A UNOS data review for safety and outcomes with common induction regimens. Pediatr Transplant 2024; 28:e14783. [PMID: 38767019 DOI: 10.1111/petr.14783] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Revised: 03/19/2024] [Accepted: 04/29/2024] [Indexed: 05/22/2024]
Abstract
BACKGROUND We hypothesized that alemtuzumab use is safe in pediatric kidney transplant recipients (KTRs) with equivalent long-term outcomes compared to other induction agents. METHODS Using pediatric kidney transplant recipient data in the UNOS database between January 1, 2000, and June 30, 2022, multivariate logistic regression, multivariable Cox regression, and survival analyses were utilized to estimate the likelihoods of 1st-year and all-time hospitalizations, acute rejection, CMV infection, delayed graft function (DGF), graft loss, and patient mortality among recipients of three common induction regimens (ATG, alemtuzumab, and basiliximab). RESULTS There were no differences in acute rejection or graft failure among induction or maintenance regimens. Basiliximab was associated with lower odds of DGF in deceased donor recipients (OR 0.77 [0.60-0.99], p = .04). Mortality was increased in patients treated with steroid-containing maintenance (HR 1.3 [1.005-1.7] p = .045). Alemtuzumab induction correlated with less risk of CMV infection than ATG (OR 0.76 [0.59-0.99], p = .039). Steroid-containing maintenance conferred lower rate of PTLD compared to steroid-free maintenance (HR 0.59 [0.4-0.8] p = .001). Alemtuzumab was associated with less risk of hospitalization within 1 year (OR 0.79 [0.67-0.95] p = .012) and 5 years (HR 0.54 [0.46-0.65] p < .001) of transplantation. Steroid maintenance also decreased 5 years hospitalization risk (HR 0.78 [0.69-0.89] p < .001). CONCLUSIONS Pediatric KTRs may be safely treated with alemtuzumab induction without increased risk of acute rejection, DGF, graft loss, or patient mortality. The decreased risk of CMV infections and lower hospitalization rates compared to other agents make alemtuzumab an attractive choice for induction in pediatric KTRs, especially in those who cannot tolerate ATG.
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Steroid-free maintenance immunosuppression using alemtuzumab in pediatric kidney transplantation: Long-term longitudinal follow-up. Pediatr Transplant 2022; 26:e14173. [PMID: 34687570 DOI: 10.1111/petr.14173] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/10/2021] [Revised: 08/17/2021] [Accepted: 10/05/2021] [Indexed: 12/01/2022]
Abstract
BACKGROUND There is a scarcity of long-term data on steroid-free immunosuppression using alemtuzumab in pediatric kidney transplantation (KTx). This study examines long-term outcomes with alemtuzumab without steroid maintenance therapy in pediatric KTx. METHODS From July 2005 to June 2015, 71 pediatric KTx recipients received alemtuzumab without steroid maintenance. They were followed from 4.1 to 14.1 years post KTx. RESULTS Patient survival: One child expired with a functioning graft from post-transplant lymphoproliferative disorder (PTLD). Patient survival was 98.6%. Graft survival: Eighteen grafts were lost (16 from chronic rejection). Graft survival at 5 and 10 years was 92.3% and 61.3%, respectively. Rejection: Twenty-three (32.4%) patients were free from T-cell-mediated rejection (TCMR), 16 (22.5%) had >3 episodes. Sixteen (22.5%) were treated for antibody-mediated rejection (AMR). Infection: Twenty-three children developed Epstein-Barr virus (EBV), 5 developed cytomegalovirus (CMV), and 20 developed BK virus infection. Four (5.6%) developed PTLD. Twenty-two (31.0%) required treatment for neutropenia. Growth parameters: Mean height and weight increased by 0.56 and 0.69 SDS (standard deviation score), respectively. Body mass index increased by 5.1 kg/m2 at 10 years. Less than 40% required antihypertensive medications at all-time points. CONCLUSION Alemtuzumab, without corticosteroid maintenance, offers 98.6% patient survival at 14 years with five and 10-year graft survival of 92.3% and 61.3%, respectively. TCMR and AMR requiring treatment were 67.4% and 22.5%, respectively. CMV, EBV, and BK viremia rates were 7.0%, 32.4%, and 28.2%, respectively. Thirty-one percent were treated for neutropenia; 5.6% developed PTLD. There were improvements in growth parameters and blood pressure.
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Steroid avoidance/withdrawal and maintenance immunosuppression in pediatric kidney transplantation. Pediatr Transplant 2022; 26:e14189. [PMID: 34786800 DOI: 10.1111/petr.14189] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/23/2021] [Revised: 09/30/2021] [Accepted: 10/06/2021] [Indexed: 12/17/2022]
Abstract
BACKGROUND Corticosteroids have been an integral part of maintenance immunosuppression for pediatric kidney transplantation. However, prolonged steroid therapy is associated with significant toxicities resulting in several SW/avoidance strategies in recent years. METHOD/OBJECTIVE This comprehensive review aims to discuss steroid-related toxicities and the safety, efficacy, and benefit of steroid avoidance/withdrawal immunosuppression in pediatric kidney transplant recipients. RESULTS Initial studies of SW/avoidance conducted in the setting of CSA and AZA showed an increased incidence of AR but no increase in graft loss or mortality with SW/avoidance maintenance immunosuppression. Studies performed under modern immunosuppression (induction therapy, Tac, and MMF) show no significant increase in AR or graft loss with SW/avoidance immunosuppression. Furthermore, SW/avoidance immunosuppression is associated with significant improvement in growth, BMI, BP control, and lipid profile in pediatric kidney transplant recipients. Despite these data, SW/avoidance remains controversial, and only 40% of pediatric kidney transplant recipients in the United States are currently on SW/avoidance maintenance immunosuppression. CONCLUSION SW/avoidance maintenance immunosuppression is safe and associated with fewer side effects compared with steroid-inclusive maintenance immunosuppression in pediatric kidney transplant recipients.
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Considerations and controversies of pharmacologic management of the pediatric kidney transplant recipient. Pharmacotherapy 2021; 41:77-102. [PMID: 33151553 DOI: 10.1002/phar.2483] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Revised: 09/18/2020] [Accepted: 10/10/2020] [Indexed: 12/23/2022]
Abstract
Pediatric kidney transplantation has experienced considerable growth and improvement in patient and allograft outcomes over the past 20 years, in part due to advancements in immunosuppressive regimens and management. Despite this progress, care for this unique population can be challenging due to limited pediatric transplant data and trials, intricacies related to differences in children and adolescents compared with their adult counterparts, and limitations to long-term survival facing all solid organ transplant populations. Immunosuppression and infection prevention practices vary from one pediatric transplant center to another and clinical controversies exist surrounding treatment and dosing. This review aims to summarize key aspects of pharmacologic management in this population and present pertinent data that describe the influence of practice to serve as a resource for practitioners caring for this unique specialty patient population. Additionally, this review highlights select controversies that exist within pediatric kidney transplantation.
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Review of the Clinical Pharmacokinetics and Pharmacodynamics of Alemtuzumab and Its Use in Kidney Transplantation. Clin Pharmacokinet 2019; 57:191-207. [PMID: 28669130 PMCID: PMC5784003 DOI: 10.1007/s40262-017-0573-x] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Alemtuzumab is a humanized monoclonal antibody against CD52 and causes depletion of T and B lymphocytes, monocytes, and NK cells. Alemtuzumab is registered for the treatment of multiple sclerosis (MS) and is also used in chronic lymphocytic leukemia (CLL). Alemtuzumab is used off-label in kidney transplantation as induction and anti-rejection therapy. The objective of this review is to present a review of the pharmacokinetics, pharmacodynamics, and use of alemtuzumab in kidney transplantation. A systematic literature search was conducted using Ovid Medline, Embase, and Cochrane Central Register of controlled trials. No pharmacokinetic or dose-finding studies of alemtuzumab have been performed in kidney transplantation. Although such studies were conducted in patients with CLL and MS, these findings cannot be directly extrapolated to transplant recipients, because CLL patients have a much higher load of CD52-positive cells and, therefore, target-mediated clearance will differ between these two indications. Alemtuzumab used as induction therapy in kidney transplantation results in a lower incidence of acute rejection compared to basiliximab therapy and comparable results as compared with rabbit anti-thymocyte globulin (rATG). Alemtuzumab used as anti-rejection therapy results in a comparable graft survival rate compared with rATG, although infusion-related side effects appear to be less. There is a need for pharmacokinetic and dose-finding studies of alemtuzumab in kidney transplant recipients to establish the optimal balance between efficacy and toxicity. Furthermore, randomized controlled trials with sufficient follow-up are necessary to provide further evidence for the treatment of severe kidney transplant rejection.
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Eight-year follow-up in pediatric living donor kidney recipients receiving alemtuzumab induction. Pediatr Transplant 2017; 21. [PMID: 28600850 DOI: 10.1111/petr.12941] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 04/13/2017] [Indexed: 01/27/2023]
Abstract
Recipient lymphocytes are crucial for direct and indirect pathways of allorecognition. We proposed that the administration of alemtuzumab several weeks pretransplantation could eradicate peripheral lymphatic cells and promote donor-specific acceptance. This was a single-center, retrospective review of 101 consecutive living donor kidney transplantations in pediatric patients (age 7 months-18 years), performed between September 2006 and April 2010. IS protocol included two 30 mg doses of alemtuzumab: The first was given 12-29 days prior to transplantation, and the second at the time of transplantation. Maintenance IS was based on combination of low-dose CNI and mycophenolate, with steroids tapered over the first 5 days post-transplantation. Patients were followed for 7.8±1.3 years, and protocol biopsies were taken 1 month, 1, 3, and 5 years post-transplant. The Kaplan-Meier 8-year patient and graft survival rates in the cyclosporine-treated patients were 82.0±7.3% and 71.6±7.3, and in the tacrolimus-treated patients were 97.2±5.4 and 83.8±6.0%. Biopsy-proven acute rejection developed in 35% of cyclosporine-treated patients and in 8% of tacrolimus-treated patients. Alemtuzumab pretreatment prior to LRD kidney transplantation, followed by maintenance immunosuppression with tacrolimus and MMF, is associated with reasonable long-term results in pediatric patients.
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Safety and Efficacy of Alemtuzumab Induction in Highly Sensitized Pediatric Renal Transplant Recipients. Transplantation 2017; 101:883-889. [PMID: 27495773 DOI: 10.1097/tp.0000000000001416] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
BACKGROUND Studies show that alemtuzumab, a potent lymphocyte-depleting agent, is well tolerated in pediatric renal transplantation. We report on the use of alemtuzumab induction in highly HLA sensitized (HS) pediatric kidney transplant patients. METHODS Fifty pediatric renal transplants were performed from 1/2009-12/2014. 15 HS patients received IVIG (2 g/kg ×2 doses)/rituximab (375 mg/m ×1) for desensitization with alemtuzumab induction (15-30 mg, 1 dose, subcutaneous), whereas 35 nonsensitized patients received anti-IL-2R. Graft survival and infections were compared between 2 groups. RESULTS All HS patients had received a prior transplant and were older with lower risk for viral infections due to serostatus. Patient survival was 100%, and graft outcomes were similar with mean 1-year creatinine of 1.03 ± 0.45 versus 0.99 ± 0.6 (P = 0.48). Although a higher incidence of acute cellular rejection was seen in HS patients receiving alemtuzumab (P = 0.001), there was a nonsignificant difference in antibody-mediated rejection. White blood cell and absolute lymphocyte count were significantly lower in alemtuzumab group at 30 days (P < 0.0001) and at 1 year (P = 0.026 and P = 0.001), respectively. There was no significant difference in bacterial, viral, or fungal infections after transplant. CONCLUSIONS Alemtuzumab induction with desensitization led to nearly equivalent graft survival and functional outcomes in HS pediatric patients as nonsensitized patients receiving anti-IL-2R induction. With this small sample size, we observed significant reduction of white blood cell and absolute lymphocyte count up to 1 year posttransplant. The risk of infection was comparable between the 2 groups; however, patients who received alemtuzumab were older and at lower risk of viral infection due to serostatus.
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Inmunosupresores y principales complicaciones en el trasplante renal pediátrico. IATREIA 2017. [DOI: 10.17533/udea.iatreia.v30n1a05] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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Impact of Human Mutant TGFβ1/Fc Protein on Memory and Regulatory T Cell Homeostasis Following Lymphodepletion in Nonhuman Primates. Am J Transplant 2016; 16:2994-3006. [PMID: 27217298 PMCID: PMC5121100 DOI: 10.1111/ajt.13883] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2015] [Revised: 04/29/2016] [Accepted: 05/07/2016] [Indexed: 01/25/2023]
Abstract
Transforming growth factor β1 (TGFβ1) plays a key role in T cell homeostasis and peripheral tolerance. We evaluated the influence of a novel human mutant TGFβ1/Fc (human IgG4 Fc) fusion protein on memory CD4+ and CD8+ T cell (Tmem) responses in vitro and their recovery following antithymocyte globulin (ATG)-mediated lymphodepletion in monkeys. TGFβ1/Fc induced Smad2/3 protein phosphorylation in rhesus and human peripheral blood mononuclear cells and augmented the suppressive effect of rapamycin on rhesus Tmem proliferation after either alloactivation or anti-CD3/CD28 stimulation. In combination with IL-2, the incidence of CD4+ CD25hi Foxp3hi regulatory T cells (Treg) and Treg:Th17 ratios were increased. In lymphodepleted monkeys, whole blood trough levels of infused TGFβ1/Fc were maintained between 2 and 7 μg/mL for 35 days. Following ATG administration, total T cell numbers were reduced markedly. In those given TGFβ1/Fc infusion, CD8+ T cell recovery to predepletion levels was delayed compared to controls. Additionally, numbers of CD4+ CD25hi CD127lo Treg increased at 4-6 weeks after depletion but subsequently declined to predepletion levels by 12 weeks. In all monkeys, CD4+ CD25hi Foxp3hi Treg/CD4+ IL-17+ cell ratios were reduced, particularly after stopping TGFβ1/Fc infusion. Thus, human TGFβ1/Fc infusion may delay Tmem recovery following lymphodepletion in nonhuman primates. Combined (low-dose) IL-2 infusion may be required to improve the Treg:Th17 ratio following lymphodepletion.
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Alemtuzumab in paediatric kidney transplantation, five years' experience at the Pablo Tobón Uribe Hospital in Medellín, Colombia. Nefrologia 2016; 36:709-711. [PMID: 27496824 DOI: 10.1016/j.nefro.2016.06.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2016] [Revised: 05/31/2016] [Accepted: 06/11/2016] [Indexed: 11/25/2022] Open
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Kidney transplantation, bioengineering and regeneration: an originally immunology-based discipline destined to transition towards ad hoc organ manufacturing and repair. Expert Rev Clin Immunol 2015; 12:169-82. [PMID: 26634874 DOI: 10.1586/1744666x.2016.1112268] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Kidney transplantation (KT), as a modality of renal replacement therapy (RRT), has been shown to be both economically and functionally superior to dialysis for the treatment of end-stage renal disease (ESRD). Progress in KT is limited by two major barriers: a) a chronic and burgeoning shortage of transplantable organs and b) the need for chronic immunosuppression following transplantation. Although ground-breaking advances in transplant immunology have improved patient survival and graft durability, a new pathway of innovation is needed in order to overcome current obstacles. Regenerative medicine (RM) holds the potential to shift the paradigm in RRT, through organ bioengineering. Manufactured organs represent a potentially inexhaustible source of transplantable grafts that would bypass the need for immunosuppressive drugs by using autologous cells to repopulate extracellular matrix (ECM) scaffolds. This overview discusses the current status of renal transplantation while reviewing the most promising innovations in RM therapy as applied to RRT.
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Characterization, prophylaxis, and treatment of infectious complications in craniomaxillofacial and upper extremity allotransplantation: a multicenter perspective. Plast Reconstr Surg 2014; 133:543e-551e. [PMID: 24675206 DOI: 10.1097/prs.0000000000000015] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
BACKGROUND Vascularized composite allotransplants consist of heterogeneous tissues from different germ layers, which include skin, muscle, bone, fat, nerves, and lymph nodes. The antigenic diversity of these tissues, particularly of the highly immunogenic skin component, necessitates potent immunosuppressive regimens similar to that of some solid organ transplants. Indeed, the lifelong, high-dose, multidrug immunosuppressive protocols expose vascularized composite allotransplant recipients to considerable risk of infectious, metabolic, and neoplastic sequelae. In this article, the authors review the infectious risk to patients after vascularized composite allotransplantation, with special attention to the somewhat limited experience with the prophylaxis and treatment of infections after this innovative reconstructive surgery. METHODS A review of the literature was undertaken to elucidate the characterization, prophylaxis, and treatment of all documented infectious complications. RESULTS Infections in face and hand vascularized composite allotransplants follow a course similar to that of solid organ transplants. Several differences exist, including the unique flora of craniomaxillofacial transplants, the increased risk of donor-derived infections, and the alteration of the risk-to-benefit ratio for cytomegalovirus infections. CONCLUSIONS The patient with a face or limb transplant has many of the same infectious risks as a lung transplant recipient, which include bacterial, viral, and fungal infections. Because of the anatomy, mucosal exposure, and differing donor flora, however, the face or limb transplant is susceptible to invasive diseases from a variety of microbes.
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Abstract
Because lymphocytes were shown to mediate transplant rejection, their depletion has been studied as a mechanism of preventing rejection and perhaps inducing immunologic tolerance. Agents that profoundly deplete lymphocytes have included monoclonal antibodies, cytotoxic drugs, and radiation. We have studied several such agents but focused on antibodies that deplete not only peripheral blood lymphocytes, but also lymph node lymphocytes. Depletion of lymph node T lymphocytes appears to permit peripheral tolerance at least for T cells in animal models. Nevertheless, B-cell responses may be resistant to such approaches, and T memory cells are likewise relatively resistant to depleting antibodies. We review the experimental and clinical approaches to depletion strategies and outline some of the pitfalls of depletion, such as limitations of currently available agents, duration of tolerance, infection, and malignancy. It is notable that most tolerogenic strategies that have been attempted experimentally and clinically include depleting agents even when they are not named as the underlying strategy. Thus, there is an implicitly acknowledged role for reducing the precursor frequency of donor antigen-specific lymphocytes when approaching the daunting goal of transplant tolerance.
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Treatment update of sensitized pediatric kidney transplant recipients: a review. EXP CLIN TRANSPLANT 2013; 10:523-30. [PMID: 23216563 DOI: 10.6002/ect.2012.0124] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Sensitization of recipients is an increasing problem in children. Some case series in children exist comparing the diverse desensitizing protocols. These protocols include intravenous immunoglobulin, cytomegalovirus immune globulin, plasmapheresis, and some adjunctive therapies such as rituximab. Desensitizing protocols have advantages and disadvantages. Clinical trials are required to determine suitable protocols for sensitized pediatric recipients. We performed a systematic review of these protocols in children. A massive search was done in PubMed, Embase, and the Cochrane library system. The results of these studies are compared.
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Abstract
OBJECTIVE To minimize maintenance immunosuppression in upper-extremity transplantation to favor the risk-benefit balance of this procedure. BACKGROUND Despite favorable outcomes, broad clinical application of reconstructive transplantation is limited by the risks and side effects of multidrug immunosuppression. We present our experience with upper-extremity transplantation under a novel, donor bone marrow (BM) cell-based treatment protocol ("Pittsburgh protocol"). METHODS Between March 2009 and September 2010, 5 patients received a bilateral hand (n = 2), a bilateral hand/forearm (n = 1), or a unilateral (n = 2) hand transplant. Patients were treated with alemtuzumab and methylprednisolone for induction, followed by tacrolimus monotherapy. On day 14, patients received an infusion of donor BM cells isolated from 9 vertebral bodies. Comprehensive follow-up included functional evaluation, imaging, and immunomonitoring. RESULTS All patients are maintained on tacrolimus monotherapy with trough levels ranging between 4 and 12 ng/mL. Skin rejections were infrequent and reversible. Patients demonstrated sustained improvements in motor function and sensory return correlating with time after transplantation and level of amputation. Side effects included transient increase in serum creatinine, hyperglycemia managed with oral hypoglycemics, minor wound infection, and hyperuricemia but no infections. Immunomonitoring revealed transient moderate levels of donor-specific antibodies, adequate immunocompetence, and no peripheral blood chimerism. Imaging demonstrated patent vessels with only mild luminal narrowing/occlusion in 1 case. Protocol skin biopsies showed absent or minimal perivascular cellular infiltrates. CONCLUSIONS Our data suggest that this BM cell-based treatment protocol is safe, is well tolerated, and allows upper-extremity transplantation using low-dose tacrolimus monotherapy.
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Allospecific CD154 + T-cytotoxic memory cells as potential surrogate for rejection risk in pediatric intestine transplantation. Pediatr Transplant 2012; 16:83-91. [PMID: 22122074 DOI: 10.1111/j.1399-3046.2011.01617.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/15/2022]
Abstract
Clinical end-points dictate large trial enrollments and exclude children with the rare intestine transplant procedure (ITx), who experience higher drug-related morbidity. We evaluate the novel rejection-risk parameter, allo-(antigen)-specific CD154 + TcMs (i) as surrogates for ACR using Prentice's criteria, (ii) for association with immunosuppression targets to determine Fleming's surrogate end-point designation, and (iii) as time-to-event end-point in a simulated comparison of alemtuzumab (NCT#01208337, n = 14) and rabbit anti-human thymocyte globulin (rATG, n = 16) among 30 children with ITx. CD154 + TcM were measured in MLR before, and at 1-60 and 61-200 days after ITx (NCT#01163578). CD154 + TcM correlate significantly with rejection severity (Spearman r = 0.685, p = 2.03E-5) and associate with biopsy-proven ITx rejection with sensitivity/specificity of 94%/84% [corrected] independent of immunosuppressant. Previously stated sensitivity of 90% is incorrect. [corrected]. The rejection-risk threshold of CD154 + TcM resolves rapidly in 200-day follow-up (46 ± 20 vs. 158 ± 59 days, p = 0.009, K-M) with alemtuzumab, which demonstrates lower 90-day ACR incidence (50% vs. 69%, p=NS, Fisher's exact), and is associated with accelerated prednisone minimization to ≤2.5 mg/day, compared with rATG (120 ± 28 vs. 180 ± 30 days, p = 0.027, K-M). As a surrogate end-point, time-to-rejection-risk resolution measured with CD154 + TcM portends 50% reduction in sample sizes in a simulated trial of alemtuzumab vs. rATG. Rejection-risk assessment with CD154 + TcM may enable informed immunosuppression minimization, and preliminary efficacy comparisons in pediatric ITx.
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Analysis of BK viral infection after alemtuzumab induction for renal transplant. Transpl Infect Dis 2011; 14:374-9. [DOI: 10.1111/j.1399-3062.2011.00694.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2011] [Revised: 08/01/2011] [Accepted: 08/26/2011] [Indexed: 11/28/2022]
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Allospecific CD154+ T-cytotoxic memory cells identify recipients experiencing acute cellular rejection after renal transplantation. Transplantation 2011; 92:433-8. [PMID: 21747326 DOI: 10.1097/tp.0b013e318225276d] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
BACKGROUND The novel, recently described allo (antigen)-specific CD154+T cells were evaluated for their association with acute cellular rejection (ACR) in 43 adult renal transplant recipients receiving steroid-free tacrolimus after alemtuzumab induction. METHODS Single blood samples corresponding to "for cause" allograft biopsies were assayed for CD154+naive or memory T-helper or T-cytotoxic cells in 16-hr mixed leukocyte reaction. RESULTS Intra- and interassay variation was less than 10% for a variety of conditions. In logistic regression, leave-one-out cross-validation, and receiver-operating characteristic analyses, the rejection-risk threshold of allospecific CD154+T-cytotoxic memory cells (TcMs) associated best with biopsy-proven ACR with a sensitivity/specificity of 88% in 32 of 43 subjects. Sensitivity/specificity of 100%/88% was replicated in blinded prediction in the remaining 11 subjects. Allospecific CD154+TcM correlated inversely with CTLA4+TcM (Spearman r=-0.358, P=0.029) and increased significantly with increasing histological severity of ACR (P=2.99E-05, Kruskall-Wallis). CONCLUSIONS The strong association between ACR and allospecific CD154+TcM may be useful in minimizing protocol biopsies among recipients at reduced rejection risk.
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The response of intestinal stem cells and epithelium after alemtuzumab administration. Cell Mol Immunol 2011; 8:325-32. [PMID: 21499290 DOI: 10.1038/cmi.2011.10] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Intestinal stem cells may have important roles in the maintenance of epithelial integrity during tissue repair. Alemtuzumab is a humanized anti-CD52 lymphocytic antibody that is increasingly being used to induce immunosuppression; intestinal barrier function is impaired during treatment with alemtuzumab. We investigated the response of intestinal stem cells to epithelial damage resulting from alemtuzumab treatment. Intestinal epithelial cell loss and abnormal Paneth cell morphology were found following a single dose of alemtuzumab. The animals receiving alemtuzumab exhibited increased apoptosis in the villi 3 days after alemtuzumab treatment and in the crypt on day 9, but apoptosis was scarce on day 35. We assessed expression of Musashi-1- and Lgr5-positive stem cells following alemtuzumab treatment. Increased numbers of cells staining positive for both Musashi-1 and Lgr5 were found in the stem cell zone after alemtuzumab treatment for 3 and 9 days. These data indicated that the epithelial cells were injured following alemtuzumab treatment, with the associated expansion of intestinal stem cells. After alemtuzumab treatment for 35 days, the numbers of intestinal epithelial cells and intestinal stem cells returned to normal. This study suggests that alemtuzumab treatment induced the increase in stem cells, resulting in the availability of more enterocytes for repair.
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Lymphocyte depletion and repopulation in peripheral blood and small intestine of cynomolgus monkeys after alemtuzumab treatment. J Surg Res 2010; 167:e21-7. [PMID: 20888596 DOI: 10.1016/j.jss.2010.08.020] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2010] [Revised: 08/10/2010] [Accepted: 08/13/2010] [Indexed: 11/28/2022]
Abstract
BACKGROUND Alemtuzumab has been used as an induction agent in organ transplantation over 10 years, but the effect of alemtuzumab on lymphocytes in small intestine was not clear. We investigate lymphocyte depletion and repopulation phenomena both in peripheral blood and small intestine of cynomolgus monkeys, to assess the model using in preclinical transplantation. MATERIALS AND METHODS Monkeys without CD52 antigen on erythrocytes were selected. Lymphocyte depletion and repopulation was documented by flow cytometry. Sections of ileum were obtained for isolation of intestinal intraepithelial lymphocytes (IEL) and lamina propria lymphocytes (LPL), and also for immunofluorescence examination. RESULTS Powerful depletion of lymphocytes (>80%) from blood followed by gradual repopulation was observed. CD20(+) B cells, CD8(+) T cells, CD4(+) T cells returned to pretreatment levels by d 21, 35, 56. IEL, LPL reduced by 70%, 72% on d 9, recovered to 59%, 57% of pretreatment levels by d 35, and were completed by d 56. Depletion and repopulation of IEL and LPL were confirmed by immunofluorescence. CONCLUSIONS Depletion of lymphocytes in peripheral blood was less powerful and repopulation occurred faster than in patients. The lymphocyte depletion and repopulation occurred in small intestine. This model can be used in preclinical transplantation.
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Successful adult-to-child renal transplantation utilizing the ovarian vein in children with inferior vena cava/iliac vein thrombosis. Pediatr Transplant 2010; 14:E70-4. [PMID: 19490488 DOI: 10.1111/j.1399-3046.2009.01132.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
IVC/iliac vein thrombosis has previously been considered to be a contraindication to renal transplantation because of the technical difficulties and the increased risk of graft thrombosis. We report two successful cases of adult-to-child kidney transplantation in which we anastomosed the graft renal vein to the recipient ovarian vein in the presence of IVC and/or iliac vein thrombosis, with no short or long term vascular complications. Our experience, which adds to the successful reports from several other centers, suggests that the inability to use the iliocaval axis should no longer be considered a contraindication to pediatric renal transplantation.
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Cytokine kinetics profiling in pediatric renal transplant recipients. Pediatr Transplant 2010; 14:636-45. [PMID: 20353407 DOI: 10.1111/j.1399-3046.2010.01309.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Pediatric renal transplant recipients experience side effects of immunosuppression. Few immunoassays exist which can assess the adequacy of immunosuppression. We developed a CKT, whereby cytokine levels are measured in a five-day mixed lymphocyte reaction. We describe the in vitro cytokine responses to donor and third-party antigen in a pilot study of nine children after living-donor renal transplantation. The CKT identified five patterns of IFN-gamma secretion relative to donor and third-party alloantigen: no response to alloantigen (n = 2), hypo-response to donor (n = 3), equal response (n = 1), hyper-response to donor (n = 1), and intermediate response (n = 2). IL-2 and IL-13 patterning correlated with IFN-gamma expression. Two of nine subjects had acute rejection, which correlated with intermediate and hyper-responsive profiles. No rejection occurred during immunosuppression or donor-specific hypo-responsiveness. Significant immunosuppression was universal early after transplantation. Two of four children showed strong pretransplant responses to donor, which were regained three months post-transplant, and associated with rejection in one subject. The CKT reflects the level of immunosuppression and may offer a method to assess the adequacy of immunosuppression. A pattern of complete non-responsiveness or hypo-responsiveness correlated with lack of acute rejection. The CKT may prove useful in titrating immunosuppression and in improving live donor selection.
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Influence of alemtuzumab on the intestinal Paneth cells and microflora in macaques. Clin Immunol 2010; 136:375-86. [PMID: 20605528 DOI: 10.1016/j.clim.2010.05.004] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2009] [Revised: 05/10/2010] [Accepted: 05/10/2010] [Indexed: 01/09/2023]
Abstract
Alemtuzumab has been recently introduced for induction therapy in organ transplantation. However, the pathogenesis and molecular mechanism of the impact of such induction therapy on bacterial infections remain to be clarified. We found the alterations of Paneth cells including abnormal Paneth cell granules and expression of lysozyme and defensin 5 in response to lymphocyte depletion by alemtuzumab. Lymphocyte depletion resulted in decreased expression of TNF-alpha, IFN-gamma, IL-10 and TGF-beta in the intestine. The diversity of gut bacteria varied significantly between different times of alemtuzumab treatment. Abnormal expression of granule peptides might result in impairment of host gut microflora. The alterations in bacterial microflora had almost reversed 56days after alemtuzumab treatment, which was consistent with our results that Paneth cells were recovered to secrete antimicrobial peptides to govern gut microflora. These findings indicated the associations between changes of Paneth cell function and gut microflora and supported the important role of Paneth cells to barrier impairment with the use of alemtuzumab in organ transplantation.
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Hand transplantation and vascularized composite tissue allografts in orthopaedics and traumatology. Orthop Traumatol Surg Res 2010; 96:283-90. [PMID: 20488148 DOI: 10.1016/j.otsr.2010.03.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Composite tissue allograft (CTA) is defined as heterologous transplantation of a complex comprising skin and subcutaneous, neurovascular and mesenchymal tissue. Such techniques allow complex reconstruction using matched tissue, without donor site morbidity. The potential indications in orthopaedics-traumatology could in the future be more frequent than the present indications of heart, lung, liver, kidney and pancreas transplantation. International clinical experience clearly demonstrates the feasibility of CTA, both surgically and immunologically. However, immunosuppression remains indispensable, exposing the patient to risks that are not acceptable for purely functional surgery, except in very particular indications. The main hope for the future lies in induction of graft-specific tolerance.
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A randomized trial to assess the impact of early steroid withdrawal on growth in pediatric renal transplantation: the TWIST study. Am J Transplant 2010; 10:828-836. [PMID: 20420639 DOI: 10.1111/j.1600-6143.2010.03047.x] [Citation(s) in RCA: 143] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Minimizing steroid exposure in pediatric renal transplant recipients can improve linear growth and reduce metabolic disorders. This randomized multicenter study investigated the impact of early steroid withdrawal on mean change in height standard deviation score (SDS) and the safety and efficacy of two immunosuppressive regimens during the first 6 months after transplantation. Children received tacrolimus, MMF, two doses of daclizumab and steroids until day 4 (TAC/MMF/DAC, n=98) or tacrolimus, MMF and standard-dose steroids (TAC/MMF/STR, n=98). Mean change in height SDS was 0.16 +/- 0.32 with TAC/MMF/DAC and 0.03 +/- 0.32 with TAC/MMF/STR. The mean treatment group difference was 0.13 (p < 0.005 [95% CI 0.04-0.22]), 0.21 in prepubertal (p = 0.009 [95% CI 0.05-0.36]) and 0.05 in pubertal children (p = ns). Frequency of biopsy-proven acute rejection was 10.2%, TAC/MMF/DAC, and 7.1%, TAC/MMF/STR. Patient and graft survival and renal function were similar. Significantly greater reductions in total cholesterol and triglycerides but significantly higher incidences of infection and anemia were found with TAC/MMF/DAC (p < 0.05 all comparisons). Early steroid withdrawal significantly aided growth at 6 months more so in prepubertal than pubertal children. This was accompanied by significantly better lipid and glucose metabolism profiles without increases in graft rejection or loss.
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Effect of anti-mouse CD52 monoclonal antibody on mouse intestinal intraepithelial lymphocytes. Transplantation 2009; 88:766-72. [PMID: 19920775 DOI: 10.1097/tp.0b013e3181b47c61] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND CD52 monoclonal antibody (mAb) has been used therapeutically in lymphocytic leukemia, autoimmune disease, and organ transplantation. But the effect of CD52 mAb on intestinal intraepithelial lymphocytes (IELs) was unknown. The aim of this study was to assess the influence of anti-mouse CD52 mAb on IELs. METHODS Twenty male C57BL/6 mice were randomly assigned to a treatment or a control group. The treatment group received anti-mouse CD52 mAb (20 mug, subcutaneously), whereas the control group received the same volume of phosphate-buffered solution. On the seventh day after treatment, mice were killed, and ileum and colon were obtained for histopathology and immunohistochemistry examination, IELs were isolated for flow cytometric analysis and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide analysis. Furthermore, the intestinal permeability was measured by lactulose-mannitol test. RESULTS The number and viability of IELs were decreased significantly in treatment compared with the control group. There were significant differences between the two groups considering IELs phenotypes. In addition, the proportion of apoptotic IELs in CD52 mAb treatment group was significantly higher than the control group (19.59%+/-3.13% and 2.02%+/-0.33%, respectively; P<0.05). Furthermore, lactulose-mannitol test showed a marked increase intestinal permeability after CD52 treatment (90.38%+/-5.96% and 46.02%+/-6.40%, respectively; P<0.05). CONCLUSION Anti-mouse CD52 mAb could induce more IELs to apoptosis and result in reducing the number of IELs, which may disrupt intestinal barrier function.
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Abstract
PURPOSE OF REVIEW The present review provides an update on the recent literature documenting the use of antibody induction in pediatric transplantation. RECENT FINDINGS The use of antibody induction has been increasing as it has been considered to be an important component of steroid-avoidance protocols following pediatric renal transplantation. According to registry data, anti-interleukin-2R monoclonal antibodies are the predominant agents being used, with slightly more patients receiving basiliximab than daclizumab. Using antibody induction, steroid avoidance is possible while maintaining rejection rates of less than 10%. Preliminary data are appearing, in which both steroid elimination and calcineurin reduction are possible. Concerns, however, are being raised about the risk of overimmunosuppression, in particular increased rates of polyoma virus and lymphoma. SUMMARY Antibody induction is firmly entrenched within the pediatric renal transplant community. There is an ongoing evolution of the types of antibodies being used. The ultimate answer for efficacy and safety will require larger samples and prospective studies.
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Renal transplantation with early steroid withdrawal. Pediatr Nephrol 2009; 24:243-51. [PMID: 18535842 DOI: 10.1007/s00467-008-0876-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/06/2008] [Revised: 04/12/2008] [Accepted: 04/15/2008] [Indexed: 12/26/2022]
Abstract
Steroids are effective immunosuppressants in renal transplantation but are associated with significant adverse effects. As a result, there has been increased interest in protocols utilizing steroid minimization. Initial trials stopped steroids at approximately 3 months, when the highest risk phase for acute rejection was over. As two randomized trials using cyclosporine and mycophenolate mofetil without induction therapy showed an unacceptably high acute rejection rate, more recent interest has focused on the cessation of steroids very early, usually within the first week after transplantation. Most protocols have used antibody induction combined with calcineurin inhibitors and mycophenolic acid derivatives. Uncontrolled studies have shown a low rate of acute rejection, but the most recent randomized controlled trials have demonstrated an increased risk of acute rejection. These trials have not shown any consistent difference in short-term patient or graft survival. Cardiovascular risk factors do not appear to be consistently improved by early steroid withdrawal. Most trials lack sufficient follow-up (5 years or more) to assess the impact of the increased acute rejection rate seen with early steroid withdrawal on long-term outcomes. Thus, the use of such protocols remains investigational.
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Two hundred living donor kidney transplantations under alemtuzumab induction and tacrolimus monotherapy: 3-year follow-up. Am J Transplant 2009; 9:355-66. [PMID: 19120078 DOI: 10.1111/j.1600-6143.2008.02492.x] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Alemtuzumab has been used in off-label studies of solid organ transplantation. We extend our report of the first 200 consecutive living donor solitary kidney transplantations under alemtuzumab pretreatment with tacrolimus monotherapy and subsequent spaced weaning to 3 years of follow-up. We focused especially on the causes of recipient death and graft loss, and the characteristics of rejection. The actuarial 1-, 2- and 3-year patient and graft survivals were 99.0% and 98.0%, 96.4% and 90.8% and 93.3% and 86.3%, respectively. The cumulative incidence of acute cellular rejection (ACR) at the following months was 2%</=6, 9.0%</=12, 16.5%</=18, 19.5%</=24, 23.5%</=30, 24.0%</=36 and 25%</=42. The mean serum creatinine (mg/dL) and glomerular filtration rate (mL/min/1.73 m(2)) at 1 and 3 years were 1.4 +/- 0.6 and 58.7 +/- 21.6 and 1.5 +/- 0.7 and 54.9 +/- 20.9, respectively. Fifty (25%) recipients had a total of 89 episodes of ACR. About 88.7% of ACR episodes were Banff 1, and of those, 82% were steroid-sensitive. Nine (4.5%) recipients had antibody-mediated rejection (AMR). About 76.5% were weaned but only 46% are currently on spaced dose (qod or less) tacrolimus monotherapy, and 94.4% remained steroid-free from the time of transplantation. Infectious complications were uncommon. This experience suggests the 3-year efficacy of this approach.
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Pediatric Living Donor Kidney Transplantation Under Alemtuzumab Pretreatment and Tacrolimus Monotherapy: 4-Year Experience. Transplantation 2008; 86:1725-31. [DOI: 10.1097/tp.0b013e3181903da7] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Calcineurin inhibitor sparing in paediatric solid organ transplantation : managing the efficacy/toxicity conundrum. Drugs 2008; 68:1385-414. [PMID: 18578558 DOI: 10.2165/00003495-200868100-00004] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Despite their efficacy, the calcineurin inhibitors (CNIs) ciclosporin and tacrolimus carry a risk of debilitating adverse effects, especially nephrotoxicity, that affect the long-term outcome and survival of children who are given organ transplants. Simple reduction in dosage of CNI has little or no long-term benefit on their adverse effects, and complete withdrawal without threatening graft outcome may only be possible after liver transplantation. Until the last decade, the only option was to increase corticosteroid and/or azathioprine doses, which imposed additional long-term hazards. Considered here are the emerging generation of new agents offering an opportunity for improving long-term graft survival, minimizing CNI-related adverse events and ensuring patient well-being.A holistic, multifaceted strategy may need to be considered - initial selection and optimized use and monitoring of immunosuppressant regimens, early recognition of indicators of patient and graft dysfunction, and, where applicable, early introduction of CNI-sparing regimens facilitating CNI withdrawal. The evidence reviewed here supports these approaches but remains far from definitive in paediatric solid organ transplantation. Because de novo immunosuppression uses CNI in more than 93% of patients, reduction of CNI-related adverse effects has focused on CNI sparing or withdrawal.A recurring theme where sirolimus and mycophenolate mofetil have been used for this purpose is the importance of their early introduction to limit CNI damage and provide long-term benefit: for example, long-term renal function critically reflects that at 1 year post-transplant. While mycophenolic acid shows advantages over sirolimus in preserving renal function because the latter is associated with proteinuria, sirolimus appears the more potent immunosuppressant but also impairs early wound healing. The use of CNI-free immunosuppressant regimens with depleting or non-depleting antibodies plus sirolimus and mycophenolic acid needs much wider investigation to achieve acceptable rejection rates and conserve renal function. The adverse effects of the alternative immunosuppressants, particularly the dyslipidaemia associated with sirolimus, needs to be minimized to avoid replacing one set of adverse effects (from CNIs) with another. While we can only conjecture that judicious combinations with the second generation of novel immunosuppressants currently in development will provide these solutions, a rationale of low-dose therapy with multiple immunosuppressants acting by complementary mechanisms seems to hold the promise for efficacy with minimal toxicity until the vision of tolerance achieves reality.
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