Human leukocyte antigen-G 3 ' untranslated region polymorphisms are associated with better kidney allograft acceptance

Human leukocyte antigen-G (FILA-G) plays a well-recognized role in the modulation of the immune response, and HLA-G expression has been associated with increased graft survival and decreased rejection episodes. To investigate the role of the HLA-G 3' untranslated region (3'UTR) in renal transplantation, we evaluated several polymorphic sites (14-bp Del/Ins +3003T/C, +3010C/G, +3027C/A, +3035C/T, +3142G/C, and +3187A/G) in patients exhibiting or not exhibiting rejection episodes. A total of 104 patients (15 with acute and 48 with chronic rejection, and 41 with no rejection) and 142 healthy individuals were studied. HLA-G 3'UTR was typed by direct sequencing. The +3035C-C genotype was more frequent in patients exhibiting chronic rejection compared with healthy controls, and the +3035C-T genotype was less frequent in chronic rejection compared with patients without rejection (acute plus chronic) or compared with healthy controls. The +3187G-A genotype, in which the A allele is associated with increased mRNA degradation, showed increased frequency in the rejection group (acute plus chronic) when compared with healthy controls. The 14 base pair Deletion/Insertion genotype was marginally increased in patients with acute rejection. This is the first study to show associations among numerous polymorphic sites in the HLA-G 3'UTR in kidney allotransplantation, which may contribute to the understanding of HLA-G post-transcriptional mechanisms. (C) 2012 American Society for Histocompatibility and Immunogenetics. Published by Elsevier Inc. All rights reserved.

The imbalance between Treg and Th17 cells caused by FTY720 treatment in skin allograft rejection

OBJECTIVES: FTY720 modulates CD4(+)T cells by the augmentation of regulatory T cell activity, secretion of suppressive cytokines and suppression of IL-17 secretion by Th17 cells. To further understand the process of graft rejection/acceptance, we evaluated skin allograft survival and associated events after FTY720 treatment. METHODS: F1 mice (C57BL/6xBALB/c) and C57BL/6 mice were used as donors for and recipients of skin transplantation, respectively. The recipients were transplanted and either not treated or treated with FTY720 by gavage for 21 days to evaluate the allograft survival. In another set of experiments, the immunological evaluation was performed five days post-transplantation. The spleens, axillary lymph nodes and skin allografts of the recipient mice were harvested for phenotyping (flow cytometry), gene expression (real-time PCR) and cytokine (Bio-Plex) analysis. RESULTS: The FTY720 treatment significantly increased skin allograft survival, reduced the number of cells in the lymph nodes and decreased the percentage of Tregs at this site in the C57BL/6 recipients. Moreover, the treatment reduced the number of graft-infiltrating cells and the percentage of CD4(+) graft-infiltrating cells. The cytokine analysis (splenocytes) showed decreased levels of IL-10, IL-6 and IL-17 in the FTY720-treated mice. We also observed a decrease in the IL-10, IL-6 and IL-23 mRNA levels, as well as an increase in the IL-27 mRNA levels, in the splenocytes of the treated group. The FTY720-treated mice exhibited increased mRNA levels of IL-10, IL-27 and IL-23 in the skin graft. CONCLUSIONS: Our results demonstrated prolonged but not indefinite skin allograft survival by FTY720 treatment. This finding indicates that the drug did not prevent the imbalance between Tr1 and Th17 cells in the graft that led to rejection.

Cellular Infiltrates and NF kappa B Subunit c-Rel Signaling in Kidney Allografts of Patients With Clinical Operational Tolerance

Background. Nuclear factor kappa B (NF kappa B) plays a potential role in tolerance by orchestrating onset and resolution of inflammation and regulatory T cell differentiation through subunit c-Rel. We characterized cellular infiltrates and expression of NF kappa B1, c-Rel and its upstream regulators phosphatidylinositol 3-kinase/RAC-alpha serine/threonine kinase, in allograft biopsies from patients with spontaneous clinical operational tolerance (COT). Methods. Paraffin-fixed kidney allograft biopsies from 40 patients with COT (n=4), interstitial rejection (IR; n=12), borderline changes (BC; n=12), and long-term allograft function without rejection (NR; n=12) were used in the study. Cellular infiltrates and immunohistochemical expression of key proteins of the NF kappa B pathway were evaluated in the cortical tubulointerstitium and in cellular infiltrates using digital image analysis software. Results were given as mean +/- SEM. Results. Biopsies from patients with COT exhibited a comparable amount of cellular infiltrate to IR, BC, and NR (COT, 191 +/- 81; IR, 291 +/- 62; BC, 178 +/- 45; and NR, 210 +/- 42 cells/mm(2)) but a significantly higher proportion of forkhead box P3-positive cells (COT, 11%+/- 1.7%; IR, 3.5%+/- 0.70%; BC, 3.4%+/- 0.57%; and NR, 3.7%+/- 0.78% of infiltrating cells; P=0.02). c-Rel expression in cellular infiltrates was significantly elevated in IR, BC, and NR when analyzing the number of positive cells per mm(2) (P=0.02) and positive cells per infiltrating cells (P=0.04). In contrast, tubular PI3K and c-Rel expression were significantly higher in IR and BC but not in NR compared with COT (P=0.03 and P=0.006, respectively). With RAC-alpha serine-threonine kinase, similar tendencies were observed (P=0.2). Conclusions. Allografts from COT patients show significant cellular infiltrates but a distinct expression of proteins involved in the NF kappa B pathway and a higher proportion of forkhead box P3-positive cells.

Low-Level Laser Therapy Decreases Renal Interstitial Fibrosis

Objective: the purpose of this study was to investigate the effect of low-level laser therapy (LLLT) on chronic kidney disease (CKD) in a model of unilateral ureteral obstruction (UUO). Background data: Regardless of the etiology, CKD involves progressive widespread tissue fibrosis, tubular atrophy, and loss of kidney function. This process also occurs in kidney allograft. At present, effective therapies for this condition are lacking. We investigated the effects of LLLT on the interstitial fibrosis that occurs after experimental UUO in rats. Methods: The occluded kidney of half of the 32 Wistar rats that underwent UUO received a single intraoperative dose of LLLT (AlGaAs laser, 780 nm, 22.5 J/cm(2), 30mW, 0.75W/cm(2), 30 sec on each of nine points). After 14 days, renal fibrosis was assessed by Sirius red staining under polarized light. Immunohistochemical analyses quantitated the renal tissue cells that expressed fibroblast (FSP-1) and myofibroblast (alpha-SMA) markers. Reverse transcriptase polymerase chain reaction (RT-PCR) was performed to determine the mRNA expression of interleukin (IL)-6, monocyte chemotactic protein-1 (MCP-1), transforming growth factor (TGF)-beta 1 and Smad3. Results: The UUO and LLLT animals had less fibrosis than the UUO animals, as well having decreased expression inflammatory and pro-fibrotic markers. Conclusions: For the first time, we showed that LLLT had a protective effect regarding renal interstitial fibrosis. It is conceivable that by attenuating inflammation, LLLT can prevent tubular activation and transdifferentiation, which are the two processes that mainly drive the renal fibrosis of the UUO model.

Tricuspid Valve Injury After Heart Transplantation Due to Endomyocardial Biopsy: An Analysis of 3550 Biopsies

Introduction. Tricuspid regurgitation (TR) is the most commonly valvular dysfunction found after heart transplantation (HTx). It may be related to endomyocardial biopsy (EMB) performed for allograft rejection surveillance. Objective. This investigation evaluated the presence of tricuspid valve tissue fragments obtained during routine EMB performed after HTx and its possible effect on short-term and long-term hemodynamic status. Method. This single-center review included prospectively collected and retrospectively analyzed data. From 1985 to 2010, 417 patients underwent 3550 EMB after HTx. All myocardial specimens were reviewed to identify the presence of tricuspid valve tissue by 2 observers initially and in doubtful cases by a third observer. The echocardiographic and hemodynamic parameters were only considered for valvular functional damage analysis in cases of tricuspid tissue inadvertently removed during EMB. Results. The 417 HTx patients to 3550 EMB, including 17,550 myocardial specimens. Tricuspid valve tissue was observed in 12 (2.9%) patients corresponding to 0.07% of the removed fragments. The echocardiographic and hemodynamic parameters of these patients before versus after the biopsy showed increased TR in 2 cases (2/12; 16.7%) quantified as moderate without progression in the long term. Only the right atrial pressure showed a significant increase (P = .0420) after tricuspid injury; however, the worsening of the functional class was not significant enough in any of the subjects. Thus, surgical intervention was not required. Conclusions. Histological evidence of chordal tissue in EMB specimens is a real-world problem of relatively low frequency. Traumatic tricuspid valve injury due to EMB rarely leads to severe valvular regurgitation; only a minority of patients develop significant clinical symptoms. Hemodynamic and echocardiographic alterations are also less often observed in most patients.

The impact of pretransplant donor-specific antibodies on graft outcome in renal transplantation: a six-year follow-up study

OBJECTIVE: The significance of pretransplant, donor-specific antibodies on long-term patient outcomes is a subject of debate. This study evaluated the impact and the presence or absence of donor-specific antibodies after kidney transplantation on short-and long-term graft outcomes. METHODS: We analyzed the frequency and dynamics of pretransplant donor-specific antibodies following renal transplantation from a randomized trial that was conducted from 2002 to 2004 and correlated these findings with patient outcomes through 2009. Transplants were performed against a complement-dependent T-and B-negative crossmatch. Pre- and posttransplant sera were available from 94 of the 118 patients (80%). Antibodies were detected using a solid-phase (Luminex (R)), single-bead assay, and all tests were performed simultaneously. RESULTS: Sixteen patients exhibited pretransplant donor-specific antibodies, but only 3 of these patients (19%) developed antibody-mediated rejection and 2 of them experienced early graft losses. Excluding these 2 losses, 6 of 14 patients exhibited donor-specific antibodies at the final follow-up exam, whereas 8 of these patients (57%) exhibited complete clearance of the donor-specific antibodies. Five other patients developed "de novo'' posttransplant donor-specific antibodies. Death-censored graft survival was similar in patients with pretransplant donor-specific and non-donor-specific antibodies after a mean follow-up period of 70 months. CONCLUSION: Pretransplant donor-specific antibodies with a negative complement-dependent cytotoxicity crossmatch are associated with a risk for the development of antibody-mediated rejection, although survival rates are similar when patients transpose the first months after receiving the graft. Our data also suggest that early posttransplant donor-specific antibody monitoring should increase knowledge of antibody dynamics and their impact on long-term graft outcome.

Immunoglobulin G profile in hyperacute rejection after multivisceral xenotransplantation

Galvao FHF, Soler W, Pompeu E, Waisberg DR, Mello ES, Costa ACL, Teodoro W, Velosa AP, Capelozzi VL, Antonangelo L, Catanozi S, Martins A, Malbouisson LMS, Cruz RJ, Figueira ER, Filho JAR, Chaib E, D'Albuquerque LAC. Immunoglobulin G profile in hyperacute rejection after multivisceral xenotransplantation. Xenotransplantation 2012; 19: 298304. (c) 2012 John Wiley & Sons A/S. Abstract: Introduction: Xenotransplantation is a potential solution for the high mortality of patients on the waiting list for multivisceral transplantation; nevertheless, hyperacute rejection (HAR) hampers this practice and motivates innovative research. In this report, we describe a model of multivisceral xenotransplantation in which we observed immunoglobulin G (IgG) involvement in HAR. Methods: We recovered en bloc multivisceral grafts (distal esophagus, stomach, small intestine, colon, liver, pancreas, and kidneys) from rabbits (n = 20) and implanted them in the swine (n = 15) or rabbits (n = 5, control). Three hours after graft reperfusion, we collected samples from all graft organs for histological study and to assess IgG fixation by immunofluorescence. Histopathologic findings were graded according to previously described methods. Results: No histopathological features of rejection were seen in the rabbit allografts. In the swine-to-rabbit grafts, features of HAR were moderate in the liver and severe in esophagus, stomach, intestines, spleen, pancreas, and kidney. Xenograft vessels were the central target of HAR. The main lesions included edema, hemorrhage, thrombosis, myosites, fibrinoid degeneration, and necrosis. IgG deposition was intense on cell membranes, mainly in the vascular endothelium. Conclusions: Rabbit-to-swine multivisceral xenotransplants undergo moderate HAR in the liver and severe HAR in the other organs. Moderate HAR in the liver suggests a degree of resistance to the humoral immune response in this organ. Strong IgG fixation in cell membranes, including vascular endothelium, confirms HAR characterized by a primary humoral immune response. This model allows appraisal of HAR in multiple organs and investigation of the livers relative resistance to this immune response.

Prevention of Intradialytic Hypotension in Patients with Acute Kidney Injury Submitted to Sustained Low-Efficiency Dialysis

Objectives: This study evaluated the effects of a protocol aiming to reduce hypotension in acute kidney injury (AKI) patients submitted to sustained low-efficiency dialysis (SLED). Methods: Patients were randomly assigned to two SLED prescriptions-control group, dialysate temperature was 37.0 degrees C with a fixed sodium concentration [138 mEq/L] and ultrafiltration (UF) rate; and profiling group, dialysate temperature was 35.5 degrees C with a variable sodium concentration [150-138 mEq/L] and UF rate. Results: Sixty-two SLED sessions were evaluated (34 in profiling and 28 in control). Patients (n = 31) were similar in terms of gender, age, and Sequential Organ Failure Assessment (SOFA) score. Dialysis time, dialysis dose, and post-dialysis serum sodium were similar in both groups. The profiling group had significantly less hypotension episodes (23% vs. 57% in control, p = 0.009) and achieved higher UF volume (2.23 +/- 1.25 L vs. 1.59 +/- 1.03 L in control, p = 0.04) when compared with control group. Conclusions: SLED protocol with modulation of dialysate temperature, sodium, and UF profiling showed similar efficacy but less intradialytic hypotension when compared with a standard SLED prescription.

Oxidative Stress and Modification of Renal Vascular Permeability Are Associated with Acute Kidney Injury during P. berghei ANKA Infection

Malaria associated-acute kidney injury (AKI) is associated with 45% of mortality in adult patients hospitalized with severe form of the disease. However, the causes that lead to a framework of malaria-associated AKI are still poorly characterized. Some clinical studies speculate that oxidative stress products, a characteristic of Plasmodium infection, as well as proinflammatory response induced by the parasite are involved in its pathophysiology. Therefore, we aimed to investigate the development of malaria-associated AKI during infection by P. berghei ANKA, with special attention to the role played by the inflammatory response and the involvement of oxidative stress. For that, we took advantage of an experimental model of severe malaria that showed significant changes in the renal pathophysiology to investigate the role of malaria infection in the renal microvascular permeability and tissue injury. Therefore, BALB/c mice were infected with P. berghei ANKA. To assess renal function, creatinine, blood urea nitrogen, and ratio of proteinuria and creatininuria were evaluated. The products of oxidative stress, as well as cytokine profile were quantified in plasma and renal tissue. The change of renal microvascular permeability, tissue hypoxia and cellular apoptosis were also evaluated. Parasite infection resulted in renal dysfunction. Furthermore, we observed increased expression of adhesion molecule, proinflammatory cytokines and products of oxidative stress, associated with a decrease mRNA expression of HO-1 in kidney tissue of infected mice. The measurement of lipoprotein oxidizability also showed a significant increase in plasma of infected animals. Together, our findings support the idea that products of oxidative stress, as well as the immune response against the parasite are crucial to changes in kidney architecture and microvascular endothelial permeability of BALB/c mice infected with P. berghei ANKA.

Chronic VEGF Blockade Worsens Glomerular Injury in the Remnant Kidney Model

VEGF inhibition can promote renal vascular and parenchymal injury, causing proteinuria, hypertension and thrombotic microangiopathy. The mechanisms underlying these side effects are unclear. We investigated the renal effects of the administration, during 45 days, of sunitinib (Su), a VEGF receptor inhibitor, to rats with 5/6 renal ablation (Nx). Adult male Munich-Wistar rats were distributed among groups S+V, sham-operated rats receiving vehicle only; S+Su, S rats given Su, 4 mg/kg/day; Nx+V, Nx rats receiving V; and Nx+Su, Nx rats receiving Su. Su caused no change in Group S. Seven and 45 days after renal ablation, renal cortical interstitium was expanded, in association with rarefaction of peritubular capillaries. Su did not worsen hypertension, proteinuria or interstitial expansion, nor did it affect capillary rarefaction, suggesting little angiogenic activity in this model. Nx animals exhibited glomerulosclerosis (GS), which was aggravated by Su. This effect could not be explained by podocyte damage, nor could it be ascribed to tuft hypertrophy or hyperplasia. GS may have derived from organization of capillary microthrombi, frequently observed in Group Nx+Su. Treatment with Su did not reduce the fractional glomerular endothelial area, suggesting functional rather than structural cell injury. Chronic VEGF inhibition has little effect on normal rats, but can affect glomerular endothelium when renal damage is already present.

Silent Ureteral Stones: Impact on Kidney Function-Can Treatment of Silent Ureteral Stones Preserve Kidney Function?

OBJECTIVE To report our experience with silent ureteral stones and expose their true influence on renal function. METHODS We analyzed 506 patients who had undergone ureterolithotripsy from January 2005 to May 2010. Silent ureteral stones were calculi found in the absence of any specific or subjective ureteral stone-related symptoms. Of the 506 patients, 27 (5.3%) met these criteria (global cohort). All patients were assessed postoperatively with dimercaptosuccinic acid scintigraphy (DMSA). A difference in relative kidney function of >10% was considered abnormal. Pre- and postoperative comparative DMSA analyses were electively obtained for 9 patients (kidney function cohort). A t test was used to assess the numeric variables, and the chi-square test or Fisher's exact test was used for categorical variables. Two-tailed P < .05 was considered statistically significant. RESULTS Stones were diagnosed by radiologic abdominal evaluation for nonurologic diseases in 40% and after previous nephrolithiasis treatment in 33%. The primary therapy was ureterolithotripsy in 88%. The mean follow-up time was 23 months. The overall ureteral stone-free rate after 1 and 2 procedures was 96% and 100%, respectively. In the global cohort, the mean pre- and postoperative serum creatinine levels were similar (P = .39), and the mean postoperative function on DMSA was 31%. In the kidney function cohort, no difference was found between the pre-and postoperative DMSA findings (22% +/- 12.1% vs 20% +/- 11.8%; P = .83) and serum creatinine (0.8 +/- 0.13 mg/dL vs 1.0 +/- 0.21 mg/dL; P = .45). CONCLUSION Silent ureteral stones are associated with decreased kidney function present at the diagnosis. Hydronephrosis tends to diminish after stone removal, and kidney function remains unaltered. UROLOGY 79: 304-309, 2012. (C) 2012 Elsevier Inc.

Long-Term Follow-Up of Patients after Acute Kidney Injury: Patterns of Renal Functional Recovery

Background and Objectives: Patients who survive acute kidney injury (AKI), especially those with partial renal recovery, present a higher long-term mortality risk. However, there is no consensus on the best time to assess renal function after an episode of acute kidney injury or agreement on the definition of renal recovery. In addition, only limited data regarding predictors of recovery are available. Design, Setting, Participants, & Measurements: From 1984 to 2009, 84 adult survivors of acute kidney injury were followed by the same nephrologist (RCRMA) for a median time of 4.1 years. Patients were seen at least once each year after discharge until end stage renal disease (ESRD) or death. In each consultation serum creatinine was measured and glomerular filtration rate estimated. Renal recovery was defined as a glomerular filtration rate value >= 60 mL/min/1.73 m2. A multiple logistic regression was performed to evaluate factors independently associated with renal recovery. Results: The median length of follow-up was 50 months (30-90 months). All patients had stabilized their glomerular filtration rates by 18 months and 83% of them stabilized earlier: up to 12 months. Renal recovery occurred in 16 patients (19%) at discharge and in 54 (64%) by 18 months. Six patients died and four patients progressed to ESRD during the follow up period. Age (OR 1.09, p < 0.0001) and serum creatinine at hospital discharge (OR 2.48, p = 0.007) were independent factors associated with non renal recovery. The acute kidney injury severity, evaluated by peak serum creatinine and need for dialysis, was not associated with non renal recovery. Conclusions: Renal recovery must be evaluated no earlier than one year after an acute kidney injury episode. Nephrology referral should be considered mainly for older patients and those with elevated serum creatinine at hospital discharge.

Histologic Inflammatory Changes on the Prostatic Gland Due to Immunosuppression for Kidney Transplantation

OBJECTIVE To determine the incidence of type IV prostatitis in patients with kidney transplantation receiving an immunosuppression regimen and to compare it with that of a nonimmunosuppressed control group. METHODS We retrospectively reviewed 216 electronic charts of patients who had undergone surgical treatment for benign prostatic hyperplasia from August 2000 to January 2006. Of the 216 patients, 183 did not receive immunosuppressive therapy and were included in the control group (group 1). The other 33 patients had undergone kidney transplantation and were included in the study group (group 2). The patient data were accessed for age at surgery, International Prostate Symptom Score, prostate volume, preoperative serum prostate-specific antigen level, history of acute urinary retention, and surgical approach (open vs transurethral resection of prostate). Histologic findings from the surgical specimens were also recorded. RESULTS The mean age at surgery, mean serum prostate-specific antigen level, mean prostate volume, and mean International Prostate Symptom Score were not significantly different between both groups. However, histologic evidence of chronic prostatitis was obtained in 145 surgical specimens (78%) from group 1 and in just 3 specimens from group 2 (9%; P < .001). Moreover, nonimmunosuppressed patients had a 38.2 times greater risk of presenting with prostatitis than did the immunosuppressed patients. CONCLUSION Imunnosuppresion therapy in kidney transplantation has a protective factor in the prostatitis incidence. UROLOGY 79: 662-664, 2012. (C) 2012 Elsevier Inc.

Lovastatin protects mithochondrial and renal function in kidney ischemia-reperfusion in rats

PURPOSE: To investigate the effect of lovastatin on renal ischemia followed by reperfusion. METHODS: Thirty one Wistar rats submitted to left renal ischemia for 60 minutes followed by contralateral nephrectomy were divided into two groups: A (n = 17, control, no treatment), and B (n = 14, lovastatin 15 mg/kg/day p.o. ten days before ischemia). The animals were sacrificed at the end of ischemia, after 24 hours and at seven days after reperfusion. Survival, serum urea and creatinine levels and renal mitochondrial function were evaluated. RESULTS: Mortality was 29.4% in group A and 0.7% in group B. Urea and creatinine levels were increased in both groups, but the values were significantly lower in group B. Mitochondrial function showed decoupling in 83.4% of group A, as opposed to 38.4/% of group B. CONCLUSIONS: The result shows a protective action of renal function by lovastatin administered before ischemia/reperfusion. Since most of the mitochondrial fraction presented membranes with the ability to maintain ATP production in group B, stabilization of the mitochondrial membrane should be considered as part of the protective action of lovastatin on renal function in ischemia/reperfusion.

Renal Function at Hospital Admission and Mortality Due to Acute Kidney Injury after Myocardial Infarction

Background: The role of an impaired estimated glomerular filtration rate (eGFR) at hospital admission in the outcome of acute kidney injury (AKI) after acute myocardial infarction (AMI) has been underreported. The aim of this study was to assess the influence of an admission eGFR<60 mL/min/1.73 m(2) on the incidence and early and late mortality of AMI-associated AKI. Methods: A prospective study of 828 AMI patients was performed. AKI was defined as a serum creatinine increase of >= 50% from the time of admission (RIFLE criteria) in the first 7 days of hospitalization. Patients were divided into subgroups according to their eGFR upon hospital admission (MDRD formula, mL/min/1.73 m(2)) and the development of AKI: eGFR >= 60 without AKI, eGFR<60 without AKI, eGFR >= 60 with AKI and eGFR<60 with AKI. Results: Overall, 14.6% of the patients in this study developed AKI. The admission eGFR had no impact on the incidence of AKI. However, the admission eGFR was associated with the outcome of AMI-associated AKI. The adjusted hazard ratios (AHR, Cox multivariate analysis) for 30-day mortality were 2.00 (95% CI 1.11-3.61) for eGFR, 60 without AKI, 4.76 (95% CI 2.45-9.26) for eGFR >= 60 with AKI and 6.27 (95% CI 3.20-12.29) for eGFR, 60 with AKI. Only an admission eGFR of <60 with AKI was significantly associated with a 30-day to 1-year mortality hazard (AHR 3.05, 95% CI 1.50-6.19). Conclusions: AKI development was associated with an increased early mortality hazard in AMI patients with either preserved or impaired admission eGFR. Only the association of impaired admission eGFR and AKI was associated with an increased hazard for late mortality among these patients.