Longitudinal monitoring of BKPyV miRNA levels in kidney transplant recipients with BKPyV-related pathology reflects viral DNA levels and remain high in viremia patients after clearance of viral DNA.

INTRODUCTION: It is unclear whether polyomavirus BK (BKPyV) microribonucleic acid (miRNA) measurement has additional diagnostic and predictive value in kidney transplant recipients (KTR) as compared to current methods of monitoring BKPyV DNA loads. PATIENTS AND METHODS: A retrospective, longitudinal study was performed in 30 KTR with BKPyV viruria (n = 10), BKPyV viremia (n = 10), or BKPyV-associated neuropathy (BKPyVAN) (n = 10). Bkv-miR-B1-3p and 5p and BKPyV DNA load were measured in urine and plasma and compared using receiver operating characteristic (ROC) curves. RESULTS: Levels of Bkv-miR-B1-3p and 5p and BKPyV DNA correlated strongly. Overall, mostly analog courses of urinary and plasma miRNA and DNA loads were observed. Areas under the ROC curves were not significantly different between miRNAs and DNA. Only, in contrast to BKPyV DNA load, BKPyV miRNA levels increased from 6 to 12 months in the viremia group, while in the BKPyVAN group, a decline was seen in both DNA and miRNA. CONCLUSIONS: In this study, we could not demonstrate an additional value of BKPyV miRNA detection compared to BKPyV DNA monitoring in the early phase after kidney transplantation. We did observe significant differences between the viremia and the BKPyVAN groups during follow-up. This study was performed with a small number of patients and therefore results should be verified in a larger patient cohort. Furthermore, future studies with larger patient groups are necessary to elucidate final clinical value of these data.

Regulatory T cells engineered with TCR signaling-responsive IL-2 nanogels suppress alloimmunity in sites of antigen encounter.

Adoptive cell transfer of ex vivo expanded regulatory T cells (Tregs) has shown immense potential in animal models of auto- and alloimmunity. However, the effective translation of such Treg therapies to the clinic has been slow. Because Treg homeostasis is known to require continuous T cell receptor (TCR) ligation and exogenous interleukin-2 (IL-2), some investigators have explored the use of low-dose IL-2 injections to increase endogenous Treg responses. Systemic IL-2 immunotherapy, however, can also lead to the activation of cytotoxic T lymphocytes and natural killer cells, causing adverse therapeutic outcomes. Here, we describe a drug delivery platform, which can be engineered to autostimulate Tregs with IL-2 in response to TCR-dependent activation, and thus activate these cells in sites of antigen encounter. To this end, protein nanogels (NGs) were synthesized with cleavable bis(N-hydroxysuccinimide) cross-linkers and IL-2/Fc fusion (IL-2) proteins to form particles that release IL-2 under reducing conditions, as found at the surface of T cells receiving stimulation through the TCR. Tregs surface-conjugated with IL-2 NGs were found to have preferential, allograft-protective effects relative to unmodified Tregs or Tregs stimulated with systemic IL-2. We demonstrate that murine and human NG-modified Tregs carrying an IL-2 cargo perform better than conventional Tregs in suppressing alloimmunity in murine and humanized mouse allotransplantation models. In all, the technology presented in this study has the potential to improve Treg transfer therapy by enabling the regulated spatiotemporal provision of IL-2 to antigen-primed Tregs.

Intradialytic Complement Activation Precedes the Development of Cardiovascular Events in Hemodialysis Patients.

Background: Hemodialysis (HD) is a life-saving treatment for patients with end stage renal disease. However, HD patients have markedly increased rates of cardiovascular morbidity and mortality. Previously, a link between the complement system and cardiovascular events (CV-events) has been reported. In HD, systemic complement activation occurs due to blood-to-membrane interaction. We hypothesize that HD-induced complement activation together with inflammation and thrombosis are involved in the development of CV-events in these patients. Methods: HD patients were followed for the occurrence of CV-events during a maximum follow-up of 45 months. Plasma samples were collected from 55 patients at different time points during one HD session prior to follow-up. Plasma levels of mannose-binding lectin, properdin and C3d/C3 ratios were assessed by ELISA. In addition, levels of von Willebrand factor, TNF-α and IL-6/IL-10 ratios were determined. An ex-vivo model of HD was used to assess the effect of complement inhibition. Results: During median follow-up of 32 months, 17 participants developed CV-events. In the CV-event group, the C3d/C3-ratio sharply increased 30 min after the start of the HD session, while in the event-free group the ratio did not increase. In accordance, HD patients that developed a CV-event also had a sustained higher IL-6/IL-10-ratio during the first 60 min of the HD session, followed by a greater rise in TNF-α levels and von Willebrand factor at the end of the session. In the ex-vivo HD model, we found that complement activation contributed to the induction of TNF-α levels, IL-6/IL-10-ratio and levels of von Willebrand factor. Conclusions: In conclusion, these findings suggest that early intradialytic complement activation predominantly occurred in HD patients who develop a CV-event during follow-up. In addition, in these patients complement activation was accompanied by a pro-inflammatory and pro-thrombotic response. Experimental complement inhibition revealed that this reaction is secondary to complement activation. Therefore, our data suggests that HD-induced complement, inflammation and coagulation are involved in the increased CV risk of HD patients.

The Complement System in Dialysis: A Forgotten Story?

Significant advances have lead to a greater understanding of the role of the complement system within nephrology. The success of the first clinically approved complement inhibitor has created renewed appreciation of complement-targeting therapeutics. Several clinical trials are currently underway to evaluate the therapeutic potential of complement inhibition in renal diseases and kidney transplantation. Although, complement has been known to be activated during dialysis for over four decades, this area of research has been neglected in recent years. Despite significant progress in biocompatibility of hemodialysis (HD) membranes and peritoneal dialysis (PD) fluids, complement activation remains an undesired effect and relevant issue. Short-term effects of complement activation include promoting inflammation and coagulation. In addition, long-term complications of dialysis, such as infection, fibrosis and cardiovascular events, are linked to the complement system. These results suggest that interventions targeting the complement system in dialysis could improve biocompatibility, dialysis efficacy, and long-term outcome. Combined with the clinical availability to safely target complement in patients, the question is not if we should inhibit complement in dialysis, but when and how. The purpose of this review is to summarize previous findings and provide a comprehensive overview of the role of the complement system in both HD and PD.

A delicate balance between rejection and BK polyomavirus associated nephropathy; A retrospective cohort study in renal transplant recipients.

BACKGROUND: The immunosuppressive agents mycophenolate acid (MPA) and tacrolimus (Tac) are associated with a higher incidence of BK polyomavirus nephropathy (BKPyVAN). In this observational retrospective cohort study, the frequency of BK polyomavirus (BKPyV) complications over a 24-month period was studied. METHODS: 358 renal transplant recipients (RTR) treated with MPA, with either cyclosporine A (CsA) (CsAM group) or Tac (TacM group) and mostly prednisolone, were included. RESULTS: Incidence of BKPyV-viremia was not significantly different between the CsAM (n = 42/191) (22.0%) and the TacM (n = 36/167) (21.6%) group. Biopsy proven BKPyVAN occurred more often in the TacM group (6.6%) versus the CsAM group (2.1%) (p = 0.03). Longitudinal data analysis showed a significant earlier decline of viral load in plasma in the CsAM group compared to the TacM group (p = 0.005). The incidence of biopsy proven acute rejection (BPAR) was significantly higher in the CsAM (19.9%) compared to the TacM (10.8%) (p = 0.02) group. Graft loss, estimated glomerular filtration rate and mortality rate did not differ in both treatment groups. CONCLUSION: In conclusion, this study shows that immunosuppressive treatment with Tac and MPA compared to CsA and MPA is associated with a lower incidence of BPAR, but at the cost of an increased risk of developing BKPyVAN in the first two years post-transplant.

Critical role for complement receptor C5aR2 in the pathogenesis of renal ischemia-reperfusion injury.

The complement system, and specifically C5a, is involved in renal ischemia-reperfusion (IR) injury. The 2 receptors for complement anaphylatoxin C5a (C5aR1 and C5aR2) are expressed on leukocytes as well as on renal epithelium. Extensive evidence shows that C5aR1 inhibition protects kidneys from IR injury; however, the role of C5aR2 in IR injury is less clear as initial studies proposed the hypothesis that C5aR2 functions as a decoy receptor. By Using wild-type, C5aR1-/-, and C5aR2-/- mice in a model of renal IR injury, we found that a deficiency of either of these receptors protected mice from renal IR injury. Surprisingly, C5aR2-/- mice were most protected and had lower creatinine levels and reduced acute tubular necrosis. Next, an in vivo migration study demonstrated that leukocyte chemotaxis was unaffected in C5aR2-/- mice, whereas neutrophil activation was reduced by C5aR2 deficiency. To further investigate the contribution of renal cell-expressed C5aR2 vs leukocyte-expressed C5aR2 to renal IR injury, bone marrow chimeras were created. Our data show that both renal cell-expressed C5aR2 and leukocyte-expressed C5aR2 mediate IR-induced renal dysfunction. These studies reveal the importance of C5aR2 in renal IR injury. They further show that C5aR2 is a functional receptor, rather than a decoy receptor, and may provide a new target for intervention.-Poppelaars, F., van Werkhoven, M. B., Kotimaa, J., Veldhuis, Z. J., Ausema, A., Broeren, S. G. M., Damman, J., Hempel, J. C., Leuvenink, H. G. D., Daha, M. R., van Son, W. J., van Kooten, C., van Os, R. P., Hillebrands, J.-L., Seelen, M. A. Critical role for complement receptor C5aR2 in the pathogenesis of renal ischemia-reperfusion injury.

High human cytomegalovirus DNAemia early post-transplantation associates with irreversible and progressive loss of renal function - a retrospective study.

Transplant recipients are prone to viral infections, which could affect renal transplantation outcome. Our aim was to assess the effects of early human cytomegalovirus (CMV) DNAemia on transplant renal function. A total of 264 (age 50.9 ± 13.5; male 55%) renal transplantation recipients undergoing preemptive anti-CMV therapy were retrospectively categorized based on early (<3 months post-Tx) CMV peak viral load (PVL); PVL ≤ 536, PVL536-6310, or PVL > 6310 International Units/ml (IU/ml). Estimated glomerular filtration rate (eGFR) was analyzed between 1 and 36 months post-transplantation with Kruskal-Wallis test, linear regression, and a linear mixed-effects model. CMV infection was detectable in 113 (43%) recipients within 49 [38-67] days. Subjects with PVL > 6310 had statistically significant ~5-13 ml/min lower eGFR between 3 and 36 months compared to PVL ≤ 536 and PVL536-6310. eGFR declined from 46.1 to 40.7 ml/min/1.73 m2 (-12%) over 3 years, and the annual decrease for pronounced infection with high PVL was 2.0 ml/min/1.73 m2 faster than for noninfected or mildly infected subjects. In conclusion, high CMV DNAemia early after renal transplantation was associated with significant loss of renal function, from which subjects did not recover. The severity of infection (high PVL early post-transplantation), more than the infection per se, was related to irreversible and progressive loss of renal function.

Incidence and outcome of BK polyomavirus infection in a multicenter randomized controlled trial with renal transplant patients receiving cyclosporine-, mycophenolate sodium-, or everolimus-based low-dose immunosuppressive therapy.

BACKGROUND: It remains unclear whether overall degree of immunosuppression or specific effects of individual immunosuppressive agents are causal for increased occurrence of BK polyomavirus (BKPyV) infection in renal transplant recipients (RTR). METHODS: A prospective, multicenter, open-label randomized controlled trial in 361 de novo RTR was performed. A total of 224 RTR were randomized at 6 months into three treatment groups with dual therapy consisting of prednisolone (Pred) plus either cyclosporine (CsA), mycophenolate sodium (MPS), or everolimus (EVL). Primary outcomes were incidence of BK viruria, BK viremia, and BKPyV-associated nephropathy (BKVAN). RESULTS: From 6 months, incidence of BK viruria in the MPS group (43.6%) was significantly higher than in the other groups (CsA: 16.9%, EVL: 19.8%) (P=.003). BKVAN was diagnosed in 3 patients, all treated with MPS (7.8%, P=.001). Longitudinal data analysis showed a lower BKPyV load and a significantly faster clearance of BK viruria in the CsA group compared to the MPS group (P=.03). CONCLUSIONS: Treatment with MPS was associated with an increased incidence of BK viruria. Dual immunosuppressive therapy with CsA and Pred was associated with the lowest rate of BKPyV replication and the fastest clearance of the virus.

Human Cytomegalovirus-Encoded Receptor US28 Is Expressed in Renal Allografts and Facilitates Viral Spreading In Vitro.

BACKGROUND: Renal transplantation is the preferred treatment for patients with end-stage renal disease. Human cytomegalovirus (HCMV) activation is associated with decreased renal graft function and survival. Human cytomegalovirus encodes several immune modulatory proteins, including the G protein-coupled receptor US28, which scavenges human chemokines and modulates intracellular signaling. METHODS: Our aim was to identify the expression and localization of US28 in renal allograft biopsies by immunohistochemistry and determine its role in viral spreading in vitro. RESULTS: Immunohistochemistry revealed US28 in 31 of 34 renal transplant biopsies from HCMV-seropositive donors. Expression was independent of HCMV viremia or IgG serostatus. US28 was predominantly expressed in the cytoplasm of vascular smooth muscle cells (VSMCs) and tubular epithelial cells, with a median positivity of 20% and 40%, respectively. Also, US28-positive cells were present within arterial neointima. In contrast to US28, HCMV-encoded immediate early antigen was detected in less than 5% of VSMCs, tubular epithelial cells, interstitial endothelium, interstitial inflammatory infiltrates, and glomerular cells.Primary VSMCs were infected with green fluorescent protein-tagged wild type or US28-deficient HCMV. The viral spreading of US28-deficient HCMV, via culture medium or cell-to-cell transmission, was significantly impeded as shown by green fluorescent protein (ie, infected) cell quantification and quantitative real-time polymerase chain reaction. Additionally, the number and size of foci was smaller. CONCLUSIONS: In summary, HCMV-encoded US28 was detected in renal allografts from HCMV-positive donors independent of viremia and serostatus. Also, US28 facilitates HCMV spreading in VSMCs in vitro. Because the vasculature is affected in chronic renal transplant dysfunction, US28 may provide a potential target for therapeutic intervention.

Strong predictive value of mannose-binding lectin levels for cardiovascular risk of hemodialysis patients.

BACKGROUND: Hemodialysis patients have higher rates of cardiovascular morbidity and mortality compared to the general population. Mannose-binding lectin (MBL) plays an important role in the development of cardiovascular disease. In addition, hemodialysis alters MBL concentration and functional activity. The present study determines the predictive value of MBL levels for future cardiac events (C-event), cardiovascular events (CV-event) and all-cause mortality in HD patients. METHODS: We conducted a prospective study of 107 patients on maintenance hemodialysis. Plasma MBL, properdin, C3d and sC5b-9 was measured before and after one dialysis session. The association with future C-events, CV-events, and all-cause mortality was evaluated using Cox regression models. RESULTS: During median follow-up of 27 months, 36 participants developed 21 C-events and 36 CV-events, whereas 37 patients died. The incidence of C-events and CV-events was significantly higher in patients with low MBL levels (<319 ng/mL, lower quartile). In fully adjusted models, low MBL level was independently associated with increased CV-events (hazard ratio 3.98; 95 % CI 1.88-8.24; P < 0.001) and C-events (hazard ratio 3.96; 95 % CI 1.49-10.54; P = 0.006). No association was found between low MBL levels and all-cause mortality. Furthermore, MBL substantially improved risk prediction for CV-events beyond currently used clinical markers. CONCLUSIONS: Low MBL levels are associated with a higher risk for future C-events and CV-events. Therefore, MBL levels may help to identify hemodialysis patients who are at risk to develop cardiovascular disease.

Precision-cut human kidney slices as a model to elucidate the process of renal fibrosis.

Chronic kidney disease is a major health concern, and experimental models bridging the gap between animal studies and clinical research are currently lacking. Here, we evaluated precision-cut kidney slices (PCKSs) as a potential model for renal disease. PCKSs were prepared from human cortical tissue obtained from tumor nephrectomies and cultured up to 96 hours. Morphology, cell viability, and metabolic functionality (ie, uridine 5'-diphospho-glucuronosyltransferase and transporter activity) were determined to assess the integrity of PCKSs. Furthermore, inflammatory and fibrosis-related gene expressions were characterized. Finally, to validate the model, renal fibrogenesis was induced using transforming growth factor ß1 (TGF-ß1). Preparation of PCKSs induced an inflammatory tissue response, whereas long-term incubation (96 hours) induced fibrogenesis as shown by an increased expression of collagen type 1A1 (COL1A1) and fibronectin 1 (FN1). Importantly, PCKSs remained functional for more than 48 hours as evidenced by active glucuronidation and phenolsulfonphthalein uptake. In addition, cellular diversity appeared to be maintained, yet we observed a clear loss of nephrin messenger RNA levels suggesting that our model might not be suitable to study the role of podocytes in renal pathology. Moreover, TGF-ß1 exposure augmented fibrosis, as illustrated by an increased expression of multiple fibrosis markers including COL1A1, FN1, and α-smooth muscle actin. In conclusion, PCKSs maintain their renal phenotype during culture and appear to be a promising model to investigate renal diseases, for example, renal fibrosis. Moreover, the human origin of PCKSs makes this model very suitable for translational research.

Assessment of Cotinine Reveals a Dose-Dependent Effect of Smoking Exposure on Long-term Outcomes After Renal Transplantation.

BACKGROUND: Smoking is a risk factor for poor late outcomes in renal transplant recipients (RTR). Smoking exposure can be assessed by self-report and cotinine measurements. We investigated whether use of cotinine as a biomarker for smoking exposure can serve as an alternative for self-report and to compare associations of smoking exposure by self-report and cotinine with outcomes in RTR and assess dose dependency. METHODS: Renal transplant recipients were classified as never, former, light (≤10 cigarettes/day), and heavy smokers (>10 cigarettes/day) according to self-report and analogous categories for urine and plasma cotinine. First, we assessed agreement of self-reported smoking exposure with smoking exposure according urine and plasma cotinine. Second, we compared the associations with graft failure and mortality. RESULTS: Of 603 RTR (age 51.5 ± 12.1 years, 55% men), 36.0% RTR were never, 42.3% former, 10.6% light, and 11.1% heavy smokers according to self-report. The majority (98.6%) of never smokers had nondetectable cotinine. However, 14 and 13 RTR reporting no active smoking had respective urine or plasma cotinine consistent with active smoking. Cotinine-based measurements were dose-dependently associated with mortality and graft failure. CONCLUSIONS: Plasma and urine cotinine can serve as an alternative to self-report and were dose-dependently associated with poor late outcomes in RTR.

Renal expression of Toll-like receptor 2 and 4: dynamics in human allograft injury and comparison to rodents.

Activation of the innate immunity through Toll-like receptors (TLRs) has been postulated to play an important role in the pathophysiology of renal allograft dysfunction. TLR2 and TLR4 dynamics in different human post-transplant pathological entities has never been studied. Therefore, we evaluated pre- and post-transplantation protein expression of TLR2 and TLR4 in human kidney biopsies. Human kidney biopsies obtained from living kidney donors and patients with acute tubular necrosis, acute cellular and vascular rejection and interstitial fibrosis/tubular atrophy (IF/TA) were used. Translating results from animal studies to the clinical situation is highly important considering the upcoming clinical studies with TLR inhibitors in human renal transplantation. Hence, the TLR2 and TLR4 expression in healthy mouse and rat kidneys was analyzed and compared with human kidneys. In healthy human kidneys, TLR2 is expressed on the endothelium and Bowman's capsule, while TLR4 is expressed on the endothelium only. No tubular staining was found for both receptors in human kidneys. In contrast to human biopsies, TLR2 and TLR4 expression in rodents was observed on tubular epithelial cells. In all acute rejection human biopsies, increased infiltration of TLR4(+) leukocytes was observed. In conclusion, a discrepancy exists between human and rodent renal TLR expression, which suggests careful attention when translating results from rodent studies to the human situation. Additionally, this study revealed human TLR2 and TLR4 expression dynamics in human biopsies pre- and post-transplantation.

N-octanoyl dopamine treatment of endothelial cells induces the unfolded protein response and results in hypometabolism and tolerance to hypothermia.

AIM: N-acyl dopamines (NADD) are gaining attention in the field of inflammatory and neurological disorders. Due to their hydrophobicity, NADD may have access to the endoplasmic reticulum (ER). We therefore investigated if NADD induce the unfolded protein response (UPR) and if this in turn influences cell behaviour. METHODS: Genome wide gene expression profiling, confirmatory qPCR and reporter assays were employed on human umbilical vein endothelial cells (HUVEC) to validate induction of UPR target genes and UPR sensor activation by N-octanoyl dopamine (NOD). Intracellular ATP, apoptosis and induction of thermotolerance were used as functional parameters to assess adaptation of HUVEC. RESULTS: NOD, but not dopamine dose dependently induces the UPR. This was also found for other synthetic NADD. Induction of the UPR was dependent on the redox activity of NADD and was not caused by selective activation of a particular UPR sensor. UPR induction did not result in cell apoptosis, yet NOD strongly impaired cell proliferation by attenuation of cells in the S-G2/M phase. Long-term treatment of HUVEC with low NOD concentration showed decreased intracellular ATP concentration paralleled with activation of AMPK. These cells were significantly more resistant to cold inflicted injury. CONCLUSIONS: We provide for the first time evidence that NADD induce the UPR in vitro. It remains to be assessed if UPR induction is causally associated with hypometabolism and thermotolerance. Further pharmacokinetic studies are warranted to address if the NADD concentrations used in vitro can be obtained in vivo and if this in turn shows therapeutic efficacy.

The clinical course of hepatitis E virus infection in patients of a tertiary Dutch hospital over a 5-year period.

BACKGROUND: Hepatitis E virus (HEV) has long been known as a major cause of acute hepatitis in developing countries with occasional travel-related cases in developed countries, most of them belonging to genotype 1. Currently, genotype 3 HEV is recognized as an emerging public health issue in developed countries and can cause a chronic hepatitis in immunocompromised patients. OBJECTIVES: The aim of this study was to get an overview of the clinical course of HEV infection, from July 2007 to December 2012, and further characterize HEV in patients of the University Medical Center Groningen (UMCG) over a 5-year time period. METHODS: Since the second half of 2007, patients in the UMCG with unexplained hepatitis were screened for HEV and clinical data were collected. HEV was characterized by sequencing of the ORF1 and ORF2 regions. RESULTS: In total, 34 patients of the 1129 tested patients showed HEV viremia. The majority of the infected patients were immunocompromised; 18 were solid organ transplant (SOT) patients and 9 were patients immunocompromised for other reasons. Seven patients diagnosed with HEV were immunocompetent. Viral genotyping revealed genotype 3 isolates, mostly genotype 3c. CONCLUSION: Non-travel related HEV hepatitis is an important diagnosis. In immunocompromised patients HEV infection often has major clinical impact, necessitating medical intervention including antiviral treatment. In immunocompetent patients, the detection could expand our understanding about the route of transmission and the relation with the zoonotic origin. Therefore, besides an increasing awareness for HEV among clinicians and medical microbiologists, diagnostics should be routinely incorporated into standard patients care.

The role of diet and physical activity in post-transplant weight gain after renal transplantation.

BACKGROUND: Long-term survival of renal transplant recipients (RTR) has not improved over the past 20 yr. The question rises to what extent lifestyle factors play a role in post-transplant weight gain and its associated risks after transplantation. METHODS: Twenty-six RTR were measured for body weight, body composition, blood lipids, renal function, dietary intake, and physical activity at six wk, and three, six, and 12 months after transplantation. RESULTS: Weight gain ranged between -2.4 kg and 19.5 kg and was largely due to increase in body fat. RTR who remained body fat stable, showed more daily physical activity (p = 0.014), tended to consume less energy from drinks and dairy (p = 0.054), consumed less mono- and disaccharides (sugars) (p = 0.021) and ate more vegetables (p = 0.043) compared with those who gained body fat. Gain in body fat was strongly related to total cholesterol (r = 0.46, p = 0.017) and triglyceride (r = 0.511, p = 0.011) at one yr after transplantation. CONCLUSIONS: Gain in adiposity after renal transplantation is related to lifestyle factors such as high consumption of energy-rich drinks, high intake of mono- and disaccharides and low daily physical activity. RCTs are needed to investigate potential benefits of lifestyle intervention on long-term morbidity and mortality.

Novel insights in localization and expression levels of C5aR and C5L2 under native and post-transplant conditions in the kidney.

AIMS: The complement system, and especially C5a, plays an important role in the pathophysiology of renal diseases and post-transplant renal injury. The two receptors for C5a are C5a receptor (C5aR) and C5a-like-receptor-2 (C5L2). Only renal C5aR expression has been reported, although exact localization and alterations in expression after transplantation are unknown. MATERIALS AND RESULTS: Renal C5aR and C5L2 expression and localization were analyzed immunohistochemically. C5aR and C5L2 expression was analyzed in human kidney biopsies obtained from living donors and patients suffering from acute tubular necrosis, acute cellular and vascular rejection or IF/TA. C5aR was expressed in the thick ascending limb of Henle's loop and first part of the distal convoluted tubule (DCT). Under inflammatory conditions, C5aR was de novo expressed in proximal tubuli. C5L2 was expressed in the kidney and localized to DCT1, DCT2 and connecting tubule. Persistent distal tubular expression of both receptors was demonstrated after renal transplantation. CONCLUSIONS: This study shows distinct renal expression patterns for C5aR and C5L2. Our findings suggest a functional role for renal C5L2 rather than being a C5a decoy receptor. Future studies focusing on renal C5a-C5aR interaction should take differential C5aR and C5L2 expression into account, alongside abundant C5aR expression on infiltrating cells.

Impact of depression on long-term outcome after renal transplantation: a prospective cohort study.

BACKGROUND: Renal transplantation is the treatment of choice for end stage renal disease. Although there is more depression in wait-listed versus transplant patients, depression persists after transplantation. We investigated the determinants of depression in renal transplantation recipients (RTRs) and the association with cardiovascular (CV) and all-cause-mortality and graft failure. METHODS: RTR were investigated between 2001 and 2003. Depression was assessed using the Depression Subscale of the Symptom Checklist (SCL-90). Mortality and graft failure were recorded until May 2009. RESULTS: A total of 527 RTR (age, 51±12 years; 55% men) were studied; 31% of the RTR were indicated with depression. Independent variables associated with depression were medically unfit for work, proteinuria, lower physical activity level, and longer dialysis duration. During follow-up for 7.0 (6.2-7.5) years, 114 RTR (59 CV) died. In Cox regression analyses, depression was strongly associated with increased risk for CV (HR=2.12 [1.27-3.53], P=0.004) and all-cause mortality (HR=1.96 [1.36-2.84], P<0.001). Adjustments for confounders did not materially change these associations. The association with graft failure (HR=1.77 [1.01-3.10]. P=0.047) disappeared after adjustment for kidney function (P=0.6). CONCLUSIONS: Although our study has several limitations, including the lack of pretransplant depression status, we identified medically unfit for work, proteinuria, lower physical activity level, and longer dialysis duration as independent variables associated with depression. We furthermore found that depression is associated with CV and all-cause mortality in RTR.

A randomized clinical trial of living donor nephrectomy: a plea for a differentiated appraisal of mini-open muscle splitting incision and hand-assisted laparoscopic donor nephrectomy.

A randomized controlled trial was designed to compare various outcome variables of the retroperitoneal mini-open muscle splitting incision (MSI) technique and the transperitoneal hand-assisted laparoscopic technique (HAL) in performing living donor nephrectomies. Fifty living kidney donors were randomized to MSI or HAL. Primary endpoint was pain experience scored on a visual analogue scale (VAS). After MSI living donors indicated lower median (range) VAS scores at rest than HAL living donors on postoperative day 2.5 [10 (0-44) vs. 15 (0-70), P = 0.043] and day 3 [7 (0-28) vs. 10 (0-91), P = 0.023] and lower VAS scores while coughing on postoperative day 3 [20 (0-73) vs. 42 (6-86), P = 0.001], day 7 [8 (0-66) vs. 33 (3-76), P < 0.001] and day 14 [2 (0-17) vs. 12 (0-51), P = 0.009]. The MSI technique also resulted in reduced morphine requirement, better scores on three domains of the RAND-36, reduced costs and reduced CRP and IL-6 levels. The HAL technique was superior in operating time and postoperative decrease of hemoglobin level. The MSI technique is superior to the HAL technique in performing living donor nephrectomies with regard to postoperative pain experience. This study reopens the discussion of the way to go in performing the living donor nephrectomy.