Immune checkpoint inhibitors induce acute interstitial nephritis in mice with increased urinary MCP1 and PD-1 glomerular expression

INTRODUCTION

Immune checkpoint inhibitors (ICIs) induce acute interstitial nephritis (AIN) in 2-5% of patients, with a clearly higher incidence when they are combined with platinum derivatives. Unfortunately, suitable disease models and non-invasive biomarkers are lacking. To fill this gap in our understanding, we investigated the renal effects of cisplatin and anti-PD-L1 antibodies in mice, assessing PD-1 renal expression and cytokine levels in mice with AIN, and then we compared these findings with those in AIN-diagnosed cancer patients.

METHODS

Twenty C57BL6J mice received 200 µg of anti-PD-L1 antibody and 5 mg/kg cisplatin intraperitoneally and were compared with those receiving cisplatin (n = 6), anti-PD-L1 (n = 7), or saline (n = 6). After 7 days, the mice were euthanized. Serum and urinary concentrations of TNFα, CXCL10, IL-6, and MCP-1 were measured by Luminex. The kidney sections were stained to determine PD-1 tissue expression. Thirty-nine cancer patients with AKI were enrolled (AIN n = 33, acute tubular necrosis (ATN) n = 6), urine MCP-1 (uMCP-1) was measured, and kidney sections were stained to assess PD-1 expression.

RESULTS

Cisplatin and anti PD-L1 treatment led to 40% AIN development (p = 0.03) in mice, accompanied by elevated serum creatinine and uMCP1. AIN-diagnosed cancer patients also had higher uMCP1 levels than ATN-diagnosed patients, confirming our previous findings. Mice with AIN exhibited interstitial PD-1 staining and stronger glomerular PD-1 expression, especially with combination treatment. Conversely, human AIN patients only showed interstitial PD-1 positivity.

CONCLUSIONS

Only mice receiving cisplatin and anti-PDL1 concomitantly developed AIN, accompanied with a more severe kidney injury. AIN induced by this drug combination was linked to elevated uMCP1, consistently with human AIN, suggesting that uMCP1 can be potentially used as an AIN biomarker.

Kidney function and other associated factors of sarcopenia in community-dwelling older adults: The SCOPE study

AIM

Sarcopenia is associated with several factors and medical conditions among older adults, though previous research has shown limitations and inconsistencies, especially regarding chronic kidney disease (CKD). We investigated the clinical and laboratory variables associated with sarcopenia and severe sarcopenia in older adults, focusing on kidney function measures.

METHODS

Data from community-dwelling adults aged ≥75 years participating in the SCOPE multicenter prospective cohort study were assessed cross-sectionally. Comprehensive geriatric assessment was conducted; sociodemographic and lifestyle factors, clinical variables and comorbidities, anthropometric and bioelectrical impedance analysis, blood and urine laboratory variables were collected. EWGSOP2 revised criteria were used to define sarcopenia and its severity. Estimated glomerular filtration rate (eGFR) was calculated using creatinine and non-creatinine-based equations, and CKD stages were defined accordingly.

RESULTS

1420 participants were included, prevalence of sarcopenia was 10.6 %, and 6 % had severe sarcopenia. Multivariate logistic regression analysis showed that age [OR =1.14; 95 %CI (1.09-1.19)], body mass index (BMI) [0.83 (0.79-0.88)], disability performing instrumental activities of daily living (IADL) [2.61 (1.69-4.06)], Mini Mental State Examination (MMSE) score <24 [2.75 (1.62-4.67)], osteoporosis [2.39 (1.55-3.67)], and stage 4 CKD defined by CKD-EPIBTP-B2M, a non-creatinine-based eGFR equation [2.88 (1.11-7.49)], were independently associated with sarcopenia; as were specifically with severe sarcopenia, with more pronounced associations.

CONCLUSIONS

In community-dwelling older adults, sarcopenia is a relevant condition and is associated with severe CKD, older age, IADL, cognitive impairments, osteoporosis and low BMI. These factors should be assessed for proper identification and management of older patients with sarcopenia, and even more so with severe sarcopenia.

False positive elevation in serum creatinine: a case report

Background

Paraproteins can interfere with several substances, producing erroneous laboratory measurements. The diagnosis of kidney disease in patients with hematological disorders has important prognosis implications. An elevated creatinine with no other signs of kidney disease should prompt the idea of a spurious creatinine. Communication between the clinical team and the laboratory is key.

Case presentation

In this case, we present a 68-year-old woman with an elevated creatinine and an IgM lambda paraprotein. Interestingly, there were no other signs of chronic kidney disease besides the creatinine value, with no albuminuria or microhematuria. A kidney biopsy showed normal parenchyma and ruled out the possibility of paraprotein-related damage. The monoclonal component and creatinine levels raised parallelly during follow-up while maintaining normal urea levels. This prompted the hypothesis of a falsely elevated creatinine. It was confirmed with a normal glomerular filtration rate determined by a radioisotope, a cystatin C measurement and a reduction in creatinine when diluting the sample.

Conclusion

It is important to consider the possibility of a falsely elevated creatinine in patients with paraproteinemia and no other signs of kidney disease to avoid unnecessary diagnostic tests and for the prognostic implications.

Combining neutrophil and macrophage biomarkers to detect active disease in ANCA vasculitis: a combinatory model of calprotectin and urine CD163

Background

CD163 and calprotectin have been proposed as biomarkers of active renal vasculitis. This study aimed to determine whether the combination of serum/urine calprotectin (s/uCalprotectin) and urinary soluble CD163 (suCD163) increases their individual performance as activity biomarkers.

Methods

We included 138 patients diagnosed with ANCA vasculitis (n = 52 diagnostic phase, n = 86 remission). The study population was divided into the inception (n = 101) and the validation cohort (n = 37). We determined the s/uCalprotectin and suCD163 concentration using ELISA at the diagnostic or at the remission phase. ROC curves were conducted to assess the biomarkers’ classificatory values. We elaborated a combinatorial biomarker model in the inception cohort. The ideal cutoffs were used in the validation cohort to confirm the model's accuracy in the distinction between active disease and remission. We added the classical ANCA vasculitis activity biomarkers to the model to increase the classificatory performance.

Results

sCalprotectin and suCD163’s concentration was higher in the diagnostic compared to the remission phase, P = 0 013 and P &lt; 0,0001. According to the ROC curves, sCalprotectin and suCD163 were accurate biomarkers to discern activity [AUC 0,73 (0,59–0 806), P = 0 015 and 0,88 (0,79–0,97), P &lt; 0,0001]. The combinatory model with the best performance in terms of sensitivity, specificity, and likelihood ratio included sCalprotectin, suCD163, and haematuria. Regarding the inception and the validation cohort, we obtained a sensibility, specificity, and a likelihood ratio of 97%, 90%, and 9,7 and 78%, 94%, and 13, respectively.

Conclusions

In patients with ANCA vasculitis, a predictive model combining sCalprotectin, suCD163, and haematuria could be useful in detecting active kidney disease.

Demonstrating Benefit-Risk Profiles of Novel Therapeutic Strategies in Kidney Transplantation: Opportunities and Challenges of Real-World Evidence

While great progress has been made in transplantation medicine, long-term graft failure and serious side effects still pose a challenge in kidney transplantation. Effective and safe long-term treatments are needed. Therefore, evidence of the lasting benefit-risk of novel therapies is required. Demonstrating superiority of novel therapies is unlikely via conventional randomized controlled trials, as long-term follow-up in large sample sizes pose statistical and operational challenges. Furthermore, endpoints generally accepted in short-term clinical trials need to be translated to real-world (RW) care settings, enabling robust assessments of novel treatments. Hence, there is an evidence gap that calls for innovative clinical trial designs, with RW evidence (RWE) providing an opportunity to facilitate longitudinal transplant research with timely translation to clinical practice. Nonetheless, the current RWE landscape shows considerable heterogeneity, with few registries capturing detailed data to support the establishment of new endpoints. The main recommendations by leading scientists in the field are increased collaboration between registries for data harmonization and leveraging the development of technology innovations for data sharing under high privacy standards. This will aid the development of clinically meaningful endpoints and data models, enabling future long-term research and ultimately establish optimal long-term outcomes for transplant patients.

Diabetes, sarcopenia and chronic kidney disease; the Screening for CKD among Older People across Europe (SCOPE) study

Background

Sarcopenia may be more present in older adults with diabetes (DM). Accordingly, we evaluated the prevalence of sarcopenia and its associated risk factors among community-dwelling older adults with DM.

Methods

A cross-sectional analysis of older people living in the community was carried out. Participants (aged 75 years and more) came from an European multicenter prospective cohort (SCOPE study). Global geriatric assessment including short physical performance battery, handgrip strength test and bioelectrical impedance analysis was performed. Sarcopenia was defined by the updated criteria of the European Working Group on Sarcopenia in Older People (EWGSOP2). Estimated glomerular filtration rate (eGFR) was calculated using Berlin Initiative Study (BIS) to define the stages of chronic kidney disease (CKD). Previous known DM was defined as physician-diagnosed DM registered in the patient's medical record or the use of DM-related medications. Hemoglobin A1c levels and specific DM therapies administered were collected. Time elapsed from the first diagnosis of DM was not collected and, therefore, was not included in the analyses.

Results

A total of 1,420 subjects were evaluated with a median age of 79.0 (6.0) years, of which 804 (56.6%) were women and 615 (43.3%) men; 315 (22.2%) participants had prior DM diagnosis, with a median age of 80.0 (6.0), 146 (46.3%) were women. Using EWGSOP2 definition, 150 (10.6%) participants in the SCOPE study met diagnostic criteria for sarcopenia. Participants without diabetes had more often normal results in the 3 sarcopenia components than participants with diabetes [887 (80.31%) vs. 227 (72.1%), p = 0.002], highlighting higher percentages of severe sarcopenia in participants with diabetes [27 (8.6%) vs. 58 (5.2%), p = 0.028]. Confirmed or severe sarcopenia was detected in 41 (13%) participants with diabetes and 109 (9.8%) participants without diabetes (p = 0.108). According to BIS equation, sarcopenia was not significantly more prevalent in the more advanced stages of CKD (p = 0.845). In multivariate analyses, older age (odds ratios [OR], 1.17; 95% confidence interval [CI], 1.08–1.27), and lower body mass index (OR, 0.79; 95% CI, 0.71–0.89 were associated with the presence of sarcopenia.

Conclusions

One tenth of all older community-dwelling subjects have sarcopenia. Older age and being thinner, but not worse renal function, were associated with higher prevalence of sarcopenia in older older adults with diabetes.

Management of post-transplant diabetes mellitus: an opportunity for novel therapeutics

Post-transplant diabetes mellitus (PTDM) is a common problem after kidney transplantation (KT), occurring in 50% of high-risk recipients. The clinical importance of PTDM lies in its impact as a significant risk factor for cardiovascular and chronic kidney disease (CKD) after solid organ transplantation. Kidney Disease: Improving Global Outcomes (KDIGO) has recently updated the treatment guidelines for diabetes management in CKD with emphasis on the newer antidiabetic agents such as dipeptidyl peptidase-4 inhibitors, glucagon-like peptide-1 receptor agonists and sodium-glucose co-transporter 2 inhibitors as add-on therapy to metformin. Given all these new diabetes treatments and the updated KDIGO guidelines, it is necessary to evaluate and give guidance on their use for DM management in KT recipients. This review summarizes the scarce published literature about the use of these new agents in the KT field. In summary, it is absolutely necessary to generate evidence in order to be able to safely use these new treatments in the KT population to improve blood glucose control, but specially to evaluate their potential cardiovascular and renal benefits that would seem to be independent of blood glucose control in PTDM patients.

Th1 Cytokines Signature in 2 Cases of IgA Nephropathy Flare after mRNA-Based SARS-CoV-2 Vaccine: Exploring the Pathophysiology

mRNA-based vaccines have dramatically shifted the course of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic. IgA nephropathy (IgAN) flare is the most reported renal adverse effect after the administration of these vaccines. Unraveling the mechanistic pathways leading to these flares is necessary to confirm a causal association. Herein, we report 2 cases of IgAN flare after SARS-CoV-2 vaccination in patients previously diagnosed with IgAN. We describe and compare the clinical and analytical features of the disease at the time of the diagnostic with the post-vaccine flare. In addition, we obtained serum and urine of these patients at the moment of the flare and determined the levels of IL-2, TNF-α, and IFNγ using a multiplex bead-based assay. As diseased controls, we included n = 13 patients diagnosed with IgAN who had available serum and urine samples at the moment of the diagnostic stored in our biobank. We also included 6 healthy controls. Compared to the first episode, postvaccination flares were more severe in terms of peak serum creatinine, albuminuria, and urinary erythrocyte count. The histological lesions found at the biopsy performed during the post-vaccine flare were similar to those found at the diagnostic. One of the patients who suffered a post-vaccine flare showed increased serum IL-2 and TNFα compared to the IgAN-diseased controls and the healthy controls. In conclusion, although several cases of post-vaccine IgAN flares have been reported, there are no mechanistic studies on the occurrence of these flares. We here suggest that hyperactivation of the Th1 pathway may be involved, but larger studies with more refined methods for numerical and functional Th1 lymphocytes evaluation are required.

In vivo CD40 Silencing by siRNA Infusion in Rodents and Evaluation by Kidney Immunostaining

The co-stimulatory molecule CD40 and its ligand CD40L play a key role in the regulation of immunological processes and are involved in the pathophysiology of autoimmune and inflammatory diseases. Inhibition of the CD40-CD40L axis is a promising therapy, and a number of strategies and techniques have been designed to hinder its functionality. Our group has broad experience in silencing CD40 using RNAi technology, and here we summarize protocols for the systemic administration of a specific anti-CD40 siRNA in different rodents models, in addition to the subsequent quantification of CD40 expression in murine kidneys by immunostaining. The use of RNAi technology with specific siRNAs to silence genes is becoming an essential method to investigate gene functions and is rapidly emerging as a therapeutic tool. Graphic abstract: CD40 siRNA mechanism.

The gene silencing of IRF5 and BLYSS effectively modulates the outcome of experimental lupus nephritis

Systemic lupus erythematosus is a highly complex and heterogeneous autoimmune disease mostly mediated by B cells. It is characterized by circulating self-reactive antibodies that deposit and form immune complexes in kidney, leading to irreparable tissue damage and resulting in lupus nephritis. In a New Zealand Black X New Zealand White F1 mouse model, we tested two different small interfering RNA (siRNA) silencing treatments against interferon regulatory factor 5 (IRF5) and B cell-activating factor (BLYSS) expression and their combination in a second set of animals. The administration of these two siRNAs separately prevented the progression of proteinuria and albuminuria at similar levels to that in cyclophosphamide animals. These treatments effectively resulted in a reduction of serum anti-double-stranded DNA (dsDNA) antibodies and histopathological renal score compared with non-treated group. Treated groups showed macrophage, T cell, and B cell infiltrate reduction in renal tissue. Moreover, kidney gene expression analysis revealed that siRNA treatments modulated very few pathways in contrast to cyclophosphamide, despite showing similar therapeutic effects. Additionally, the combined therapy tested in a second set of animals, in which the disease appeared more virulent, exhibited better results than monotherapies in the disease progression, delaying the disease onset and ameliorating the disease outcome. Herein, we provide the potential therapeutic effect of both selective IRF5 and BLYSS silencing as an effective and potential treatment, particularly in early phases of the disease.

Donor/Recipient HLA Molecular Mismatch Scores Predict Primary Humoral and Cellular Alloimmunity in Kidney Transplantation

Donor/recipient molecular human leukocyte antigen (HLA) mismatch predicts primary B-cell alloimmune activation, yet the impact on de novo donor-specific T-cell alloimmunity (dnDST) remains undetermined. The hypothesis of our study is that donor/recipient HLA mismatches assessed at the molecular level may also influence a higher susceptibility to the development of posttransplant primary T-cell alloimmunity. In this prospective observational study, 169 consecutive kidney transplant recipients without preformed donor-specific antibodies (DSA) and with high resolution donor/recipient HLA typing were evaluated for HLA molecular mismatch scores using different informatic algorithms [amino acid mismatch, eplet MM, and Predicted Indirectly Recognizable HLA Epitopes (PIRCHE-II)]. Primary donor-specific alloimmune activation over the first 2 years posttransplantation was assessed by means of both dnDSA and dnDST using single antigen bead (SAB) and IFN-γ ELISPOT assays, respectively. Also, the predominant alloantigen presenting pathway priming DST alloimmunity and the contribution of main alloreactive T-cell subsets were further characterized in vitro. Pretransplantation, 78/169 (46%) were DST+ whereas 91/169 (54%) DST−. At 2 years, 54/169 (32%) patients showed detectable DST responses: 23/54 (42%) dnDST and 31/54 (57%) persistently positive (persistDST+). 24/169 (14%) patients developed dnDSA. A strong correlation was observed between the three distinct molecular mismatch scores and they all accurately predicted dnDSA formation, in particular at the DQ locus. Likewise, HLA molecular incompatibility predicted the advent of dnDST, especially when assessed by PIRCHE-II score (OR 1.014 95% CI 1.001–1.03, p=0.04). While pretransplant DST predicted the development of posttransplant BPAR (OR 5.18, 95% CI=1.64–16.34, p=0.005) and particularly T cell mediated rejection (OR 5.33, 95% CI=1.45–19.66, p=0.012), patients developing dnDST were at significantly higher risk of subsequent dnDSA formation (HR 2.64, 95% CI=1.08–6.45, p=0.03). In vitro experiments showed that unlike preformed DST that is predominantly primed by CD8+ direct pathway T cells, posttransplant DST may also be activated by the indirect pathway of alloantigen presentation, and predominantly driven by CD4+ alloreactive T cells in an important proportion of patients. De novo donor-specific cellular alloreactivity seems to precede subsequent humoral alloimmune activation and is influenced by a poor donor/recipient HLA molecular matching.

Progress in the Development and Challenges for the Use of Artificial Kidneys and Wearable Dialysis Devices

Background

Renal transplantation is the treatment of choice for chronic kidney disease (CKD) patients, but the shortage of kidneys and the disabling medical conditions these patients suffer from make dialysis essential for most of them. Since dialysis drastically affects the patients' lifestyle, there are great expectations for the development of wearable artificial kidneys, although their use is currently impeded by major concerns about safety. On the other hand, dialysis patients with hemodynamic instability do not usually tolerate intermittent dialysis therapy because of their inability to adapt to a changing scenario of unforeseen events. Thus, the development of novel wearable dialysis devices and the improvement of clinical tolerance will need contributions from new branches of engineering such as artificial intelligence (AI) and machine learning (ML) for the real-time analysis of equipment alarms, dialysis parameters, and patient-related data with a real-time feedback response. These technologies are endowed with abilities normally associated with human intelligence such as learning, problem solving, human speech understanding, or planning and decision-making. Examples of common applications of AI are visual perception (computer vision), speech recognition, and language translation. In this review, we discuss recent progresses in the area of dialysis and challenges for the use of AI in the development of artificial kidneys.

Summary and Key Messages

Emerging technologies derived from AI, ML, electronics, and robotics will offer great opportunities for dialysis therapy, but much innovation is needed before we achieve a smart dialysis machine able to analyze and understand changes in patient homeostasis and to respond appropriately in real time. Great efforts are being made in the fields of tissue engineering and regenerative medicine to provide alternative cell-based approaches for the treatment of renal failure, including bioartificial renal systems and the implantation of bioengineered kidney constructs.

ANRIL as a genetic marker for cardiovascular events in renal transplant patients - an observational follow-up cohort study

Cardiovascular disease is the leading cause of morbidity and mortality in kidney transplant recipients. Several single-nucleotide polymorphisms (SNPs) in the ANRIL gene pathway have been associated with cardiovascular events (CE). The main objective was to ascertain whether ANRIL (rs10757278) and CARD8 (rs2043211) SNPs could mediate susceptibility to CE. This was an observational follow-up cohort study of renal transplant recipients at Bellvitge University Hospital (Barcelona) from 2000 to 2014. A total of 505 recipients were followed up until achievement of a CE. Patients who did not achieve the endpoint were followed up until graft loss, lost to follow-up or death. Survival analysis was used to ascertain association between genetic markers, clinical data, and outcome. Fifty-three patients suffered a CE after renal transplantation. Results showed a significant association between ANRIL SNP and CE. Homozygous GG for the risk allele showed higher risk for CE than A carriers for the protective allele [HR = 2.93(1.69-5.11), P < 0.0001]. This effect was maintained when it was analyzed in combination with CARD8, suggesting that CARD8 SNP could play a role in the ANRIL mechanism. However, our study does not clarify the molecular mechanism for the CARD8 SNP regulation by ANRIL. ANRIL SNP may predispose to the development of CE after successful kidney transplantation.

Artificial Intelligence for the Artificial Kidney: Pointers to the Future of a Personalized Hemodialysis Therapy

Background

Current dialysis devices are not able to react when unexpected changes occur during dialysis treatment or to learn about experience for therapy personalization. Furthermore, great efforts are dedicated to develop miniaturized artificial kidneys to achieve a continuous and personalized dialysis therapy, in order to improve the patient's quality of life. These innovative dialysis devices will require a real-time monitoring of equipment alarms, dialysis parameters, and patient-related data to ensure patient safety and to allow instantaneous changes of the dialysis prescription for the assessment of their adequacy. The analysis and evaluation of the resulting large-scale data sets enters the realm of "big data" and will require real-time predictive models. These may come from the fields of machine learning and computational intelligence, both included in artificial intelligence, a branch of engineering involved with the creation of devices that simulate intelligent behavior. The incorporation of artificial intelligence should provide a fully new approach to data analysis, enabling future advances in personalized dialysis therapies. With the purpose to learn about the present and potential future impact on medicine from experts in artificial intelligence and machine learning, a scientific meeting was organized in the Hospital Universitari Bellvitge (L'Hospitalet, Barcelona). As an outcome of that meeting, the aim of this review is to investigate artificial intel ligence experiences on dialysis, with a focus on potential barriers, challenges, and prospects for future applications of these technologies.

Summary and Key Messages

Artificial intelligence research on dialysis is still in an early stage, and the main challenge relies on interpretability and/or comprehensibility of data models when applied to decision making. Artificial neural networks and medical decision support systems have been used to make predictions about anemia, total body water, or intradialysis hypotension and are promising approaches for the prescription and monitoring of hemodialysis therapy. Current dialysis machines are continuously improving due to innovative technological developments, but patient safety is still a key challenge. Real-time monitoring systems, coupled with automatic instantaneous biofeedback, will allow changing dialysis prescriptions continuously. The integration of vital sign monitoring with dialysis parameters will produce large data sets that will require the use of data analysis techniques, possibly from the area of machine learning, in order to make better decisions and increase the safety of patients.

Early Conversion From Calcineurin Inhibitor- to Everolimus-Based Therapy Following Kidney Transplantation: Results of the Randomized ELEVATE Trial

In a 24-month, multicenter, open-label, randomized trial, 715 de novo kidney transplant recipients were randomized at 10-14 weeks to convert to everolimus (n = 359) or remain on standard calcineurin inhibitor (CNI) therapy (n = 356; 231 tacrolimus; 125 cyclosporine), all with mycophenolic acid and steroids. The primary endpoint, change in estimated glomerular filtration rate (eGFR) from randomization to month 12, was similar for everolimus versus CNI: mean (standard error) 0.3(1.5) mL/min/1.73² versus -1.5(1.5) mL/min/1.73² (p = 0.116). Biopsy-proven acute rejection (BPAR) at month 12 was more frequent under everolimus versus CNI overall (9.7% vs. 4.8%, p = 0.014) and versus tacrolimus-treated patients (2.6%, p < 0.001) but similar to cyclosporine-treated patients (8.8%, p = 0.755). Reporting on de novo donor-specific antibodies (DSA) was limited but suggested more frequent anti-HLA Class I DSA under everolimus. Change in left ventricular mass index was similar. Discontinuation due to adverse events was more frequent with everolimus (23.6%) versus CNI (8.4%). In conclusion, conversion to everolimus at 10-14 weeks posttransplant was associated with renal function similar to that with standard therapy overall. Rates of BPAR were low in all groups, but lower with tacrolimus than everolimus.

Data on genotypic distribution and linkage disequilibrium of several ANRIL polymorphisms in hemodialysis patients

A long non-coding RNA called ANRIL located on chromosome 9p21.3 has been identified as a novel genetic factor associated with cardiovascular disease. Investigation of several single nucleotide polymorphisms (SNPs) of Noncoding Antisense RNA in the INK4 Locus (ANRIL) gene are of particular interest. This article reports data related to the research article entitled: “Association of ANRIL gene polymorphisms with major adverse cardiovascular events in hemodialysis patients” (Arbiol-Roca et al. [1]). Data presented show the genotypic distribution of four selected ANRIL SNPs: rs10757278, rs4977574, rs10757274 and rs6475606 in a cohort constituted by 284 hemodialysis patients. This article analyzes the Hardy-Weinberg disequilibrium of each studied SNP, and the linkage disequilibrium between them.

Current and novel biomarkers in anti-neutrophil cytoplasm-associated vasculitis

Anti-neutrophil cytoplasm antibody (ANCA)-associated vasculitis (AAV) is characterized by a variable disease course, with up to 50% of patients having one relapse within 5 years and many progressing to end-stage organ damage despite modern treatment strategies. Moreover, complications arising from treatment dominate the causes of mortality and morbidity both early and late during disease, especially in the elderly and those with severe renal involvement, and there is additional uncertainty as to how long treatment should be continued. There is, therefore, an urgent clinical need to identify robust biomarkers to better predict treatment responses, risk of disease relapse and eventual complete clinical and immunological quiescence. To date, no such biomarkers exist, but better understanding of disease pathogenesis and the underlying immune dysfunction has provided some potential candidates linked to the discovery of new antibodies, different leukocyte activation states, the role of the alternative complement pathway and markers of vascular activation. With all promising new biomarkers, there is the need to rapidly replicate and validate early findings using large biobanks of samples that could be brought together by leaders in the field.

Abstract 357: Antioxidant and Anti-inflammatory Strategies Prevent Endothelial Dysfunction in Chronic Kidney Disease

Accelerated atherosclerosis in chronic kidney disease (CKD) is preceded by the development of endothelial dysfunction (ED), with development of a proinflammatory and prothrombotic phenotype and enhanced oxidative stress. The effect of anti-inflammatory and antioxidant strategies on the endothelium has been evaluated in an in vitro model of ED in uremia.

Endothelial cells (ECs) were pretreated with the antioxidant enzyme mimetics ebselen, EUK-134 and EUK-118; the flavonoids apigenin, genistein and quercetin, with both antioxidant and anti-inflammatory potential; and two commercially available compounds: N-acetylcysteine (NAC) and defibrotide (DF). There is increasing evidence demonstrating that both NAC and DF exhibit both properties. ECs were exposed to medium containing serum from patients on dialysis (n=10) or from healthy donors (n=15). Changes in the expression of the adhesion receptor ICAM-1 and the production of intracellular reactive oxygen species (ROS) were assessed. Activation of inflammation-related proteins p38 MAPK and NFkappaB (NFκB) were also evaluated.

Exposure of ECs to uremic media resulted in a significantly increased expression of ICAM-1, overproduction of ROS and activation of p38MAPK and NFκB compared to control ECs (p<0.05). Ebselen, EUK 134, and EUK118 inhibited ICAM-1 expression and ROS generation in the uremic condition (p<0.01). Regarding flavonoids, only quercetin showed a moderated but significant inhibitory effect on both parameters (p<0.05). NAC and DF exhibited a protective effect on ECs exposed to the uremic insult (p<0.05 for ICAM-1 expression and ROS generation). All the compounds reduced p38MAPK activation (p<0.05). The antioxidant-enzyme mimetics and NAC were able to inhibit the activation of NFκB induced by the uremic media (p<0.05).

Endothelial dysfunction associated with CKD is considered to be the first step in the progression of atherosclerosis. Our results indicate that the antioxidant enzyme mimetics, NAC and DF exhibit not only antioxidant but also anti-inflammatory effects on the endothelium. Therefore, further research on the protective effects of these compounds may provide new strategies for the prevention of the cardiovascular complications in uremia.

Sterile leukocyturia is associated with interstitial fibrosis and tubular atrophy in kidney allograft protocol biopsies

Kidney allograft interstitial fibrosis and tubular atrophy (IF/TA) is associated with a poorer renal function and outcome. In the current clinical practice, an early diagnosis can only be provided by invasive tests. We aimed to investigate the association of sterile leukocyturia with Banff criteria histological findings in kidney allograft protocol biopsies. We studied 348 allograft biopsies from two different European countries performed at 8.5 + 3.5 months after transplantation. In these cases, the presence of sterile leukocyturia (Leuc+, n = 70) or no leukocyturia (Leuc-, n = 278) was analyzed and related to Banff elementary lesions. Only IF/TA was significantly different between Leuc+ and Leuc- groups. IF/TA was present in 85.7% of Leuc+ and 27.7% of Leuc- patients (p < 0.001). IF/TA patients had higher serum creatinine and presence of proteinuria (p < 0.05). Independent predictors of IF/TA were donor age, donor male sex, serum creatinine and Leuc+ (hazard ratio 18.2; 95% confidence interval, 8.1-40.7). The positive predictive value of leukocyturia for predicting IF/TA was 85.7% whereas the negative predictive value was 72.3%. These studies suggest that leukocyturia is a noninvasive and low-cost test to identify IF/TA. An early diagnosis may allow timely interventional measures directed to minimize its impact and improve graft outcome.

Pretransplant immediately early-1-specific T cell responses provide protection for CMV infection after kidney transplantation

Cytomegalovirus (CMV) infection is still a major complication after kidney transplantation. Although cytotoxic CMV-specific T cells play a crucial role controlling CMV survival and replication, current pretransplant risk assessment for CMV infection is only based on donor/recipient (IgG)-serostatus. Here, we evaluated the usefulness of monitoring pre- and 6-month CMV-specific T cell responses against two dominant CMV antigens (IE-1 and pp65) and a CMV lysate, using an IFN-γ Elispot, for predicting the advent of CMV infection in two cohorts of 137 kidney transplant recipients either receiving routine prophylaxis (n = 39) or preemptive treatment (n = 98). Incidence of CMV antigenemia/disease within the prophylaxis and preemptive group was 28%/20% and 22%/12%, respectively. Patients developing CMV infection showed significantly lower anti-IE-1-specific T cell responses than those that did not in both groups (p < 0.05). In a ROC curve analysis, low pretransplant anti-IE-1-specific T cell responses predicted the risk of both primary and late-onset CMV infection with high sensitivity and specificity (AUC > 0.70). Furthermore, when using most sensitive and specific Elispot cut-off values, a higher than 80% and 90% sensitivity and negative predictive value was obtained, respectively. Monitoring IE-1-specific T cell responses before transplantation may be useful for predicting posttransplant risk of CMV infection, thus potentially guiding decision-making regarding CMV preventive treatment.

Cross-validation of IFN-γ Elispot assay for measuring alloreactive memory/effector T cell responses in renal transplant recipients

Assessment of donor-specific alloreactive memory/effector T cell responses using an IFN-γ Elispot assay has been suggested to be a novel immune-monitoring tool for evaluating the cellular immune risk in renal transplantation. Here, we report the cross-validation data of the IFN-γ Elispot assay performed within different European laboratories taking part of the EU RISET consortium. For this purpose, development of a standard operating procedure (SOP), comparisons of lectures of IFN-γ plates assessing intra- and interlaboratory assay variability of allogeneic or peptide stimuli in both healthy and kidney transplant individuals have been the main objectives. We show that the use of a same SOP and count-settings of the Elispot bioreader allow low coefficient variation between laboratories. Frozen and shipped samples display slightly lower detectable IFN-γ frequencies than fresh samples. Importantly, a close correlation between different laboratories is obtained when measuring high frequencies of antigen-specific primed/memory T cell alloresponses. Interestingly, significant high donor-specific alloreactive T cell responses can be similarly detected among different laboratories in kidney transplant patients displaying histological patterns of acute T cell mediated rejection. In conclusion, assessment of circulating alloreactive memory/effector T cells using an INF-γ Elispot assay can be accurately achieved using the same SOP, Elispot bioreader and experienced technicians in kidney transplantation.

Dendritic cells phenotype fitting under hypoxia or lipopolysaccharide; adenosine 5'-triphosphate-binding cassette transporters far beyond an efflux pump

This study examines adenosine 5'-triphosphate-binding cassette (ABC) transporters as a potential therapeutic target in dendritic cell (DC) modulation under hypoxia and lipopolysaccharide (LPS). Functional capacity of dendritic cells (DCs) (mixed lymphocyte reaction: MLR) and maturation of iDCs were evaluated in the presence or absence of specific ABC-transporter inhibitors. Monocyte-derived DCs were cultured in the presence of interleukin (IL)-4/granulocyte-macrophage colony-stimulating factor (GM-CSF). Their maturation under hypoxia or LPS conditions was evaluated by assessing the expression of maturation phenotypes using flow cytometry. The effect of ABC transporters on DC maturation was determined using specific inhibitors for multi-drug resistance (MDR1) and multi-drug resistance proteins (MRPs). Depending on their maturation status to elicit T cell alloresponses, the functional capacity of DCs was studied by MLR. Mature DCs showed higher P-glycoprotein (Pgp) expression with confocal microscopy. Up-regulation of maturation markers was observed in hypoxia and LPS-DC, defining two different DC subpopulation profiles, plasmacytoid versus conventional-like, respectively, and different cytokine release T helper type 2 (Th2) versus Th1, depending on the stimuli. Furthermore, hypoxia-DCs induced more B lymphocyte proliferation than control-iDC (56% versus 9%), while LPS-DCs induced more CD8-lymphocyte proliferation (67% versus 16%). ABC transporter-inhibitors strongly abrogated DC maturation [half maximal inhibitory concentration (IC50 ): P-glycoprotein inhibition using valspodar (PSC833) 5 μM, CAS 115104-28-4 (MK571) 50 μM and probenecid 2·5 μM], induced significantly less lymphocyte proliferation and reduced cytokine release compared with stimulated-DCs without inhibitors. We conclude that diverse stimuli, hypoxia or LPS induce different profiles in the maturation and functionality of DC. Pgp appears to play a role in these DC events. Thus, ABC-transporters emerge as potential targets in immunosuppressive therapies interfering with DCs maturation, thereby abrogating innate immune response when it is activated after ischaemia.

Long-term results of biopsy-guided selection and allocation of kidneys from older donors in older recipients

In our old-for-old program, we discard or allocate older extended criteria donor kidneys to single (SKT) or dual kidney transplantation (DKT) depending on histological Remuzzi's score in recipients older than 60 years. Here, we analyze the long-term results of this program and try to identify independent predictors of patient and graft survival. Between December 1996 and January 2008, we performed 115 SKT and 88 DKT. Discard rate was 15%. Acute rejection incidence was higher in SKT than in DKT (22.6% vs. 11.4%, p = 0.04). Renal function was better in DKT than in SKT up to 5 years after transplantation. Surgical complications were frequent in DKT. Ten-year cumulative graft survival was significantly lower in the SKT group (31% vs. 53%, p = 0.03). In SKT, histological score 4 provided similar graft survival than 3 or less, whereas in DKT score 4, 5 or 6 displayed similar outcome. Finally, independent predictors of graft survival were history of major adverse cardiac event and 1-year serum creatinine, rather than SKT or DKT. In conclusion, this biopsy-guided old-for-old strategy resulted in acceptable long-term graft survival. Our results suggest that DKT should be considered for scores of 5 or 6 only.

Geriatric assessment and chronic kidney disease in the oldest old: the Octabaix study

BACKGROUND

The prevalence of chronic kidney disease (CKD) in older people is increasing. We determine the proportion of CKD in a sample of 321, 85-year-old community-dwelling subjects, and assess the association of socio-demographic data, global geriatric assessment data and comorbidity with CKD according to the estimated glomerular filtration rate (eGFR) of subjects.

METHODS

Serum creatinine, eGFR (derived in ml/min/1.73 m(2) using the Modification of Diet in Renal Disease formula), socio-demographic variables, the Barthel Index (BI), the Spanish version of the Mini-Mental State Examination (MEC), the Mini Nutritional Assessment (MNA), the Charlson Index, the Gait Rating Scale, social risk, quality of life and prevalent chronic diseases were collected.

RESULTS

CKD prevalence was 56.7% for eGFR < 60 ml/min/1.73 m(2), 19.9% for eGFR < 45 ml/min/1.73 m(2) and 6.6% for GFR < 30 ml/min/1.73 m(2). Multiple logistic regression analysis showed that a prior diagnosis of hypertension was associated with an eGFR < 60 ml/min/1.73 m(2) (p<0.008, OR 2.134, 95% CI 1.216-3.744). A diagnosis of heart failure (p<0.001, OR 3.610, 95% CI 1.677-7.771) and a poor score on the quality of life measure (p<0.008, OR 0.9660, 95% CI 0.966-0.995) were associated with an eGFR < 45 ml/min/1.73 m(2).

CONCLUSIONS

More than half of the oldest old in this study had an eGFR < 60 ml/min/1.73 m(2). A history of hypertension was associated with CKD. The group of patients with an eGFR < 45 ml/min/1.73 m(2) was associated with a diagnosis of heart failure and a worse quality of life.

Successful outcome of ganciclovir-resistant cytomegalovirus infection in organ transplant recipients after conversion to mTOR inhibitors

Ganciclovir-resistant (GanR) cytomegalovirus (CMV) infection after organ transplantation is emerging as a significant therapeutic challenge. We report two cases of GanR CMV infection successfully managed by switching immunosuppression from calcineurin inhibitors to an mTOR inhibitor-based regimen. This salvage therapy should be considered when other options are not available.

Intragraft regulatory T cells in protocol biopsies retain foxp3 demethylation and are protective biomarkers for kidney graft outcome

Presence of subclinical rejection (SCR) with IF/TA in protocol biopsies of renal allografts has been shown to be an independent predictor factor of graft loss. Also, intragraft Foxp3+ T(reg) cells in patients with SCR has been suggested to differentiate harmful from potentially protective infiltrates. Nonetheless, whether presence of Foxp3 T(reg) cells in patients with SCR and IF/TA may potentially protect from a deleterious graft outcome has not yet been evaluated. This is a case-control study in which 37 patients with the diagnosis of SCR and 68 control patients with no cellular infiltrates at 6-month protocol biopsies matched for age and time of transplantation were evaluated. We first confirmed that numbers of intragraft Foxp3-expressing T cells in patients with SCR positively correlates with Foxp3 demethylation at the T(reg) -specific demethylation region. Patients with SCR without Foxp3+ T(reg) cells within graft infiltrates showed significantly worse 5-year graft function evolution than patients with SCR and Foxp3+ T(reg) cells and those without SCR. When presence of SCR and IF/TA were assessed together, presence of Foxp3+ T(reg) could discriminate a subgroup of patients showing the same graft outcome as patients with a normal biopsy. Thus, presence of Foxp3+ T(reg) cells in patients with SCR even with IF/TA is associated with a favorable long-term allograft outcome.

In vivo therapeutic efficacy of intra-renal CD40 silencing in a model of humoral acute rejection

The humoral branch of the immune response has an important role in acute and chronic allograft dysfunction. The CD40/CD40L costimulatory pathway is crucial in B- and T- alloresponse. Our group has developed a new small interfering RNA (siRNA) molecule against CD40 that effectively inhibits its expression. The aim of the present study was to prevent rejection in an acute vascular rejection model of kidney transplant by intra-graft gene silencing with anti-CD40 siRNA (siCD40), associated or not with sub-therapeutic rapamycin. Four groups were designed: unspecific siRNA as control; sub-therapeutic rapamycin; siCD40; and combination therapy. Long-surviving rats were found only in both siCD40-treated groups. The CD40 mRNA was overexpressed in control grafts but treatment with siCD40 decreased its expression. Recipient spleen CD40+ B-lymphocytes were reduced in both siCD40-treated groups. Moreover, CD40 silencing reduced donor-specific antibodies, graft complement deposition and immune-inflammatory mediators. The characteristic histological features of humoral rejection were not found in siCD40-treated grafts, which showed a more cellular histological pattern. Therefore, the intra-renal effective blockade of the CD40/CD40L signal reduces the graft inflammation as well as the incidence of humoral vascular acute rejection, finally changing the type of rejection from humoral to cellular.

Tubular epithelial cells transfected with hHGF counteracts monocyte chemotactic protein-1 up-regulation after hypoxia/reoxygenation insult

Acute kidney injury (AKI) which is mainly produced by nephrotoxic or ischemic insults is correlated with a high mortality and morbidity. Proximal tubular epithelial cells (PTEC) play a major role. They are the main target of ischemia/reperfusion injury. PTECs have also been proposed as the effectors of AKI reversibility, but also as the creator of the inflammatory milieu: cytokine, chemokine, and complement expression. An important chemokine implicated in this process is monocyte chemotactic protein-1 (MCP-1) due to its ability to recruit and activate monocytes. Hepatocyte growth factor (HGF) is a pleiotropic factor with mitogenic, anti-apoptotic, and proliferative effects which has recently been studied for its anti-inflammatory and antifibrogenic effects. Our aim was to evaluate the potential inflammatory effect of hypoxia and reoxygenation on rat PTECs. We created a stable human HGF (hHGF) expressing PTEC line that emulated in vivo transfection and analyzed the role of this cell type in the induction and reversibility of AKI. Our results showed the efficiency of transfection with the hHGF gene to promote sustained expression of the protein in the medium (7627.13 +/- 1144.078 to 8211.3 +/- 795.37 pg/mL). When rat PTECs were under a hypoxia/reoxygenation insult, MCP-1 was highly overexpressed (4479.3 +/- 154.3 pg/mL of protein and 5.099 +/- 1.23 times control gene expression). Transfected cells abrogated this effect (288.7 +/- 13.5 pg/mL and 1.169 +/- 0.0759 times control). In conclusion, we observed that the hypoxia/reoxygenation insult stimulated MCP-1 protein secretion in PTECs and that PTECs which were stably transfected and overexpressing hHGF abrogated the inflammatory reaction mediated by hypoxia/reoxygenation, being a suitable model for later studies.

Successful renal transplantation in a patient with atypical hemolytic uremic syndrome carrying mutations in both factor I and MCP

Kidney transplantation in patients with atypical hemolytic uremic syndrome (aHUS) carrying mutations in the soluble complement regulators factor H (CFH) or factor I (CFI) is associated with elevated risk of disease recurrence and almost certain graft loss. In contrast, recurrence is unusual in patients with mutations in the membrane-associated complement regulator membrane cofactor protein (MCP) (CD46). Therefore, a panel of experts recently recommended the combined liver-kidney transplantation to minimize aHUS recurrence in patients with mutations in CFH or CFI. There was, however, very limited information regarding transplantation in patients carrying mutations in both soluble and membrane-associated complement regulators to support a recommendation. Here, we report the case of an aHUS patient with a heterozygous mutation in both CFI and MCP who received an isolated kidney transplant expressing normal MCP levels. Critically, the patient suffered from a severe antibody-mediated rejection that was successfully treated with plasmapheresis and IvIgG. Most important, despite the complement activation in the allograft, there was no evidence of thrombotic microangiopathy, suggesting that the normal MCP levels in the grafted kidney were sufficient to prevent the aHUS recurrence. Our results suggest that isolated kidney transplantation may be a good first option for care in aHUS patients carrying CFI/MCP combined heterozygous mutations.

Immunephenotype of glomerular and interstitial infiltrating cells in protocol renal allograft biopsies and histological diagnosis

Patients with a protocol renal allograft biopsy simultaneously displaying interstitial fibrosis/tubular atrophy (IF/TA) and subclinical rejection (SCR) have a shortened graft survival than patients with a normal biopsy, or with a biopsy only displaying IF/TA or SCR. The poor outcome of these patients could be related with a more severe inflammation. We evaluate the immunophenotype of infiltrating cells in these diagnostic categories. Nonexhausted paraffin blocks from protocol biopsies done during the first year were stained with anti-CD45, CD3, CD20, CD68 and CD15 monoclonal antibodies. Glomerular and interstitial positive cells were counted. C4d deposition in peritubular capillaries was evaluated. Histological diagnoses were: normal (n = 80), SCR (n = 17), IF/TA (n = 42) and IF/TA + SCR (n = 17). Only interstitial CD20 positive cells were significantly increased in patients displaying IF/TA + SCR; normal (137 +/- 117), SCR (202 +/- 145), IF/TA (208 +/- 151) and IF/TA + SCR (307 +/- 180 cells/mm(2)), p < 0.01. The proportion of biopsies displaying C4d deposition was not different among groups. The upper tertile of CD20 positive interstitial cells was associated with a decreased death-censored graft survival (relative risk: 3.01, 95% confidence interval: 1.23-7.35; p = 0.015). These data suggest that B-cell interstitial infiltrates are associated with histological damage and outcome, but do not distinguish whether these infiltrates were the cause or the consequence of chronic tubulo-interstitial damage.

Gastrointestinal complications in renal transplant recipients: MITOS study

INTRODUCTION AND METHODS

An epidemiologic multicenter study was performed to evaluate the prevalence and management of gastrointestinal (GI) complications in solid organ transplant patients. A total of 1788 recipients were included, 1132 of which corresponded to renal transplanted patients.

RESULTS

The mean age for the renal transplanted patients was 52 +/- 13.2 years. The mean time from the transplantation was 5.4 +/- 5.4 years. 17.7% showed some pretransplant GI disease, while 53% presented this type of complication in the posttransplant period. Diarrhea was the most prevalent GI complication (51.5%) and digestive perforation was the GI disorder that affected the patients daily living the most. From the patients with GI complications, 71% received pharmacological treatment, using gastric protectors in 91.3% of the cases. Regarding immunosuppressive drugs, in 30.9% of the cases the dose of the drug was reduced, in 9.3% discontinued temporarily and in 7.5% discontinued permanently. These changes mainly affected the MMF (89%, 83% and 74% for dose change, temporary and permanent discontinuation, respectively).

CONCLUSIONS

The prevalence of GI complications in renal transplant exceeded 50%, and affected patients' daily living. The management of these complications was based on treatment with gastric protectors, dose reduction and/or partial or definitive MMF discontinuation.

Preliminary Results of Treatment With Pegylated Interferon Alpha 2A for Chronic Hepatitis C Virus in Kidney Transplant Candidates on Hemodialysis

INTRODUCTION

At present, there is little published information on the outcome of treatment with pegylated interferon (Peg-IF alpha 2a) in hepatitis C virus (HCV)-infected hemodialysis patients awaiting renal transplantation. The objective of this study was to assess the efficacy and tolerance of Peg-IF alpha 2a in this population.

PATIENTS AND METHODS

Twelve noncirrhotic HCV-infected patients (10 men, 50 +/- 8 years of age, genotype 1b 84%), were prescribed Peg-IF alpha 2a, at 135 microg/wk for 48 weeks. Liver biopsy was performed in 11 of 12 cases.

RESULTS

Six patients completed 48 weeks of treatment, with one end of treatment response (ETR), two sustained viral responses (SVRs), and three HCV relapses. Treatment was shorter in the six remaining patients: two cases 24 weeks (one due to medical reasons with relapse, one due to nonresponse), one patient chose to discontinue at 14 weeks (with relapse), one patient died of stroke at 10 weeks, and in two additional patients interferon was withdrawn at 18 weeks because of severe anemia (SVR) and at 26 weeks due to prolonged fever (relapse). Other secondary treatment-related events included anemia (requiring transfusion in two patients and major erythropoietin administration in six), and fever in four patients.

CONCLUSIONS

Peg-IF had limited efficacy in this group, with ETR in 83%, SVR in only 25%, and recurrence in 50%. Tolerance was moderate, with 4/12 (33%) discontinuing treatment due to adverse events, personal decision, or death. Large randomized controlled studies are needed to determine the role of Peg-IF treatment in this population.

Donor Structural and Functional Parameters Are Independent Predictors of Renal Function at 3 Months

INTRODUCTION

Epidemiological studies have shown that demographic, clinical, and histological donor characteristics influence renal function after transplantation, but whether these variables are independent predictors has not been established. The aim of this study was to evaluate the relative contribution of different donor variables on glomerular filtration rates (GFRs) at 3 months.

PATIENTS AND METHODS

We analyzed single renal transplants performed at our center from January 2000 to July 2004. Donor variables included age, gender, weight and height, cause of death, duration of brain death, serum creatinine at admission and preprocurement, history of arterial hypertension or diabetes mellitus, and smoking habit. Donor chronic damage score was calculated in preimplantation biopsies as was the addition of interstitial fibrosis, fibrous intimal thickening, and glomerulosclerosis (<10% = 0, >10% = 1). Donor and recipient GFRs were calculated according to the Cockroft-Gault formula.

RESULTS

We analyzed 202 transplants obtained from 113 deceased donors. A renal biopsy was available in 111 transplants. Recipient GFR at 3 months correlated negatively with donor age (R = -0.32, P < .01) and donor chronic damage score (R = 0.32, P < .01). GFR was lower among recipients of female versus male donors (50 +/- 15 vs 60 +/- 20 mL/min; P < .01). Donor cerebrovascular accident death (53 +/- 19 vs 63 +/- 19 mL/min; P < .01) and hypertension (48 +/- 16 vs 59 +/- 20 mL/min; P < .01) were also associated with lower GFR at 3 months. There was a positive correlation between GFR at admission, GFR preprocurement, and GFR at 3 months (R = 0.32 and R = 0.18 respectively; P < .01). Stepwise regression analysis included chronic damage score, GFR at admission, and donor gender but not donor age as independent predictors of GFR at 3 months (R = 0.50; P < .01).

CONCLUSION

Donor structural and functional parameters are independent predictors of renal function at 3 months.

New immunosuppresor strategies in the treatment of murine lupus nephritis

Renal involvement in systemic lupus erythematosus is a common complication that significantly worsens morbidity and mortality. Although treatment with corticosteroids and cytotoxic drugs may be useful in many cases, morbidity associated with these drugs and the relapsing nature of the disease make it necessary to develop new treatment strategies. Five-month old female NZB/W F1 mice were divided into the following groups: CYP group (n = 10), cyclophosphamide (CYP) 50 mg/kg intraperitoneally every 10 days; RAPA 1 group (n = 10) oral daily sirolimus (SRL), 1 mg/kg; RAPA 12 group (n = 13), oral daily SRL, 12mg/kg; FTY group (n = 10), oral fingolimod (FTY720), 2 mg/kg three times per week. An additional group of 13 non-treated mice were used as a control (control group). Follow-up was performed over four months. Animal survival, body weight, anti-DNA antibodies and proteinuria were determined. Kidneys were processed for conventional histology and immunofluorescence for IgG and complement. Total histological score (HS) was the sum of mesangial expansion, endocapillary proliferation glomerular deposits, extracapillary proliferation, interstitial infiltrates, tubular atrophy and interstitial fibrosis. All treated groups had lower proteinuria at the end of the follow-up with respect to the control group (P < 0.0001). Serum anti-DNA antibodies were appropriately controlled in RAPA 1 and CYP groups, but not in FTY or RAPA 12 groups. SRL and CYP arrested, and perhaps reversed almost all histological lesions. FTY720 ameliorated histological lesions but did not control mesangial expansion or interstitial infiltrates. SRL produces great improvement in murine lupus nephritis, while FTY720 seems a promising alternative if used in appropriate doses.

Immunosuppression for dual kidney transplantation with marginal organs: the old is better yet

Immunosuppressive protocols in dual kidney transplantation (DKT) are based on calcineurin inhibitors (CNI). We wonder whether a CNI-free immunosuppression can improve outcome in older patients receiving a DKT with marginal donor organs. Thirty-six were treated with CsA, MMF and prednisone (CsA group) and 42 with rATG, SRL, MMF and prednisone (SRL group). Incidence of delayed graft function and acute rejection was 44% and 11% in the CsA group, and 40% and 8% in the SRL group. CMV infection incidence was low in both protocols. Three-year patient survival was 89% in the CsA and 76% in the SRL group. One- and 3-year graft survival after censoring for dead with a functioning allograft was 94.2% and 94% in CsA and 95% and 90% in SRL, respectively. Renal function was similar in both groups whereas proteinuria was higher in the SRL group. Uninephrectomy due to graft thrombosis or urinary-related complications was numerically higher in the SRL (21%) than in the CsA group (8%) (p = 0.13) and it was associated with renal failure and proteinuria. In DKT, a new induction immunosuppressive protocol based on rATG, SRL, MMF and prednisone does not offer any advantage in comparison to the old CsA, MMF and prednisone.