Oxidative stress in chronic kidney disease

Patients with chronic kidney disease (CKD) have high incidence rates of cardiovascular disease and malignancy. Several factors contribute to these conditions. Structural characteristics in CKD, loss of renal energy, and uremia result in an imbalance between free radical production and antioxidant defenses. Also, CKD patients usually have multiple cardiovascular risk factors like diabetes mellitus, dyslipidemia, and hypertension. These conditions are associated with oxidative stress, which can trigger the inflammatory process and accelerate renal injury progression. There are some clinical biomarkers to detect oxidative stress and antioxidant status in CKD patients. Antioxidant therapies may be beneficial in reducing oxidative stress, lowering uremic cardiovascular toxicity, and improving survival. Therefore, their roles in CKD patients have been evaluated in several studies as a new target for therapeutic intervention. This review provides an overview of oxidative stress mechanisms, clinical squeals, biomarkers, and possible antioxidant therapies in CKD patients.

Association of programmed cell death 1 and programmed cell death 1 ligand gene polymorphisms with delayed graft function and acute rejection in kidney allograft recipients

INTRODUCTION

The genetic variations of co-stimulatory molecules can affect the extent of T cell activity during T-cell mediated immunity, especially in transplant patients. This study aimed to investigate the association of programmed cell death 1 (PDCD1) and programmed cell death 1 ligand 1 (PDCD1LG1) gene polymorphisms with clinical outcome of kidney transplantation.

MATERIALS AND METHODS

A total of 122 patients with a kidney transplant were included in this retrospective study. Patients were classified into two groups of biopsy-proven acute allograft rejection (AAR) and stable graft function (SGF) during the 5-year follow-up period. Four single nucleotide polymorphisms in PDCD1 and PDCD1LG1 were determined in the groups of patients as well as in 208 healthy control individuals.

RESULTS

The frequencies of PD-1.3 (+7146 G>A), PD-1.9 (+7625 C>T), PD-L1 (8923 A>C), and PD-L1 (+6777 C>G) genotypes and alleles were not significantly different between the AAR and SGF groups. In comparison with healthy controls, PD-1.9 (+7625 C>T) genotype and T allele were significantly more frequent in all of the patients and in those with SGF. Overall, 27 of 122 kidney allograft recipients experienced delayed graft function, and a higher frequency of PD-1.9 (+7625 C>T) genotype and T allele was observed in this group versus those without delayed graft function. Similarly, a significant high frequency of this genotype was found among the AAR subgroup of patients with delayed graft function.

CONCLUSIONS

Our results indicate that potentially functional genetic variation in PDCD1 can influence the outcome of kidney transplantation.

Soluble major histocompatibility complex class I chain-related antigen A level in chronic allograft dysfunction

INTRODUCTION

Soluble major histocompatibility complex class I chain-related antigen A (soluble MICA) has recently been considered as an inhibitory molecule which is shed from tumors and protects them against natural killers and some subgroups of T cells' cytolysis. In transplantation, soluble MICA is also a foreign antigenic molecule that can induce allospecific responses. This study aimed to clarify its possible role in long-term kidney allograft outcome.

MATERIALS AND METHODS

Thirty patients with biopsy-proven chronic allograft dysfunction (CAD) were pair-matched with kidney allograft recipients with 30 stable graft function. Fifteen healthy individuals were enrolled as controls. Soluble MICA antigen and anti-HLA antibodies were measured in their serum.

RESULTS

There was no significant difference between CAD patients, stable recipients, and healthy volunteers in frequency or titer of soluble MICA; however, soluble MICA-positive patients were more frequent in the stable group was than the CAD group (43.4% versus 33.3%). In addition, a high level of soluble MICA was accompanied by enhanced humoral responses. No significant difference was found in anti-HLA antibodies production between the CAD and stable groups.

CONCLUSIONS

Our data suggest that soluble MICA, at least in a defined range, can protect the allograft against natural killers and T cell cytolysis; nonetheless, its excessive amounts might stimulate immune system to exert enhanced humoral response. In order to confirm the protective or detrimental role of soluble MICA in kidney transplantation, conducting larger studies is necessary.

Effect of N-acetyl cysteine and vitamin C on kidney allograft function biomarkers interleukin-18 and neutrophil gelatinase-associated lipocalin

INTRODUCTION

Delayed graft function (DGF) is a consequence of ischemia-reperfusion injuries in kidney allografts, for which no definite treatment is available. The neutrophil gelatinase-associated lipocalin (NGAL) and interleukin-18 (IL-18) are introduced as the most promising urine biomarkers to detect DGF. N-acetylcysteine (NAC) and vitamin C, well-known potent antioxidants that scavenge free radicals, may alleviate kidney injury. This study investigated the protective effects of NAC alone and in combination with vitamin C on DGF, by measuring IL-18 and NGAL in living donor kidney transplantations.

MATERIALS AND METHODS

Patients transplanted between January 2011 and February 2013 were randomly divided into 3 groups to receive routine anti-rejection medication only (n = 32), NAC plus routine immunosuppressive regimen (NAC group; n = 33), and NAC and vitamin C plus routine regimen (NAC and vitamin C group; n = 19). Urine samples were taken 4 hours and 24 hours after transplantation. Enzyme-linked immunosorbent assay kits were utilized for measuring urine NGAL and IL-18.

RESULTS

There were no significant differences in the DGF prevalence and its duration between the study arms. Although the levels of NGAL and IL-18 decreased in the NAC and NAC and vitamin C groups, these reductions were not significant. Glomerular filtration rate at 30 and 60 days after transplantation were not significantly different between study groups, either.

CONCLUSIONS

Our results showed that NAC is a safe drug without significant adverse effects in kidney transplant recipients; however, its potential useful effects on urinary biomarkers of DGF were not illustrated in the present study.

Predictive urinary biomarkers for steroid-resistant and steroid-sensitive focal segmental glomerulosclerosis using high resolution mass spectrometry and multivariate statistical analysis

Background

Focal segmental glomerulosclerosis (FSGS) is a glomerular scarring disease diagnosed mostly by kidney biopsy. Since there is currently no diagnostic test that can accurately predict steroid responsiveness in FSGS, prediction of the responsiveness of patients to steroid therapy with noninvasive means has become a critical issue. In the present study urinary proteomics was used as a noninvasive tool to discover potential predictive biomarkers.

Methods

Urinary proteome of 10 patients (n = 6 steroid-sensitive, n = 4 steroid-resistant) with biopsy proven FSGS was analyzed using nano-LC-MS/MS and supervised multivariate statistical analysis was performed.

Results

Twenty one proteins were identified as discriminating species among which apolipoprotein A-1 and Matrix-remodeling protein 8 had the most drastic fold changes being over- and underrepresented, respectively, in steroid sensitive compared to steroid resistant urine samples. Gene ontology enrichment analysis revealed acute inflammatory response as the dominant biological process.

Conclusion

The obtained results suggest a panel of predictive biomarkers for FSGS. Proteins involved in the inflammatory response are shown to be implicated in the responsiveness. As a tool for biomarker discovery, urinary proteomics is especially fruitful in the area of prediction of responsiveness to drugs. Further validation of these biomarkers is however needed.

Regulatory T cell subtypes and TGF-β1 gene expression in chronic allograft dysfunction

BACKGROUND

Regulatory T cells have been suggested to have a protective role against acute rejection in allograft recipients. However, there is little information available about their contribution to chronic rejection process. The role of transforming growth factor-beta 1 (TGF-β1) as a profibrogenic and/or immunoregulatory cytokine in renal allografts is also controversial.

OBJECTIVES

To evaluate the frequency of CD4+CD25+CD127- and CD3+CD8+CD28- regulatory T cells in chronic allograft dysfunction (CAD) and to investigate the expression of TGF-β1 in renal allografts.

METHODS

Thirty biopsy-proven CAD patients were pair-matched with 30 stable graft function patients and a third group of healthy volunteers. Flowcytometry was performed on PBMCs to determine the frequency of CD3+CD8+CD28- and CD4+CD25+CD127- regulatory T cells in lymphocyt population. TGF-β1 gene expression was assessed by Real Time PCR.

RESULTS

The percentages of CD3+CD8+CD28- Tregs among renal allograft recipients was higher than healthy controls (p<0.001) since stable graft patients showed the most rates. The frequency of CD4+CD25+CD127- Tregs was lower in CAD patients than stable recipients (p=0.024) and healthy group (p=0.015). TGF-β1 gene expression was greater in CAD patients compared to healthy group (p=0.03) but there was no significant difference between gene expression of stable graft patients and healthy volunteers.

CONCLUSION

The negative association between the frequency of regulatory T cell subtypes and chronic allograft dysfunction proposes these cells as probable candidates for promoting allograft survival. Moreover, despite the immunoregulatory capacity of TGF-β1, it is likely to be implicated in chronic damages of allograft tissue.

Effects of pioglitazone on blood glucose and inflammatory markers of diabetic kidney transplant patients: a randomized controlled trial

INTRODUCTION

The aim of this study was to assess the effects of pioglitazone on blood glucose control and inflammatory biomarkers in diabetic patients receiving insulin after kidney transplantation.

MATERIALS AND METHODS

In a randomized placebo-controlled trial, 62 diabetic kidney transplant patients were followed for 4 months after randomly assigned to placebo and pioglitazone (30 mg/d) groups. All of the patients continued their insulin therapy irrespective of the group that they were assigned to, in order to evaluate the effects of addition of pioglitazone on blood glucose and inflammation biomarkers including serum C-reactive protein, high-sensitivity C-reactive protein, and interleukin-18 levels, as well as erythrocyte sedimentation rate.

RESULTS

At baseline, there were no significant differences in laboratory studies between the two groups. After 4 months of intervention, along with significant improvement in hemoglobin A1c in the pioglitazone group, daily insulin requirements also decreased and lipid profile improved significantly. In addition, erythrocyte sedimentation rate, C-reactive protein, and high-sensitivity C-reactive protein values were significantly lower in the pioglitazone group (P = .03, P < .001, and P = .01). Interleukin-18 levels were not significantly different at the end of the study between the two groups, but it had a decreasing trend in the pioglitazone group (P = .002).

CONCLUSIONS

Pioglitazone complementing insulin in diabetic kidney transplant patients not only improved glycemic control, evidenced by hemoglobin A1c, and reduced daily insulin requirement, but also decreased inflammatory markers which may have an impact on overall cardiovascular events and mortalities beyond glycemic control.

Prevalence and risk factors of recurrent cytomegalovirus infection in kidney transplant recipients

INTRODUCTION

Recurrence of cytomegalovirus (CMV) infection following solid organ transplantation causes mortality and morbidity in allograft recipients. The aim of this study was to evaluate prevalence and risk factors of recurrent CMV infection in kidney transplant patients.

MATERIALS AND METHODS

Four hundred and twenty-seven consecutive kidney transplant recipients were included in this retrospective cohort study. Both donors and recipients were CMV seropositive. Recurrent CMV infection (symptomatic or asymptomatic) was defined as detection of CMV infection in a patient who has had previously documented infection and who had not have virus detected for an interval of at least 4 weeks during active surveillance.

RESULTS

Of 427 recipients, 71 (16.6%) had CMV infection, of which 19 (4.4%) were recurrent infection. Donor source, dialysis duration before transplantation, recipient and donor age and sex, and administration of antithymocyte globulin and prophylactic treatment ganciclovir were not associated with CMV infection or recurrence. The use of tacrolimus in the immunosuppressive regimen as compared to cyclosporine was an independent risk factor for CMV infection but not recurrent infection.

CONCLUSIONS

Intensive immunosuppressive regimen, such as using tacrolimus, might be associated with a higher risk for CMV infection, but this study was not able to document the same association for recurrent CMV disease. In patients receiving immunosuppressive regimens that include tacrolimus and antithymocyte globulin, prophylactic treatment for CMV disease with ganciclovir is recommended.

Urinary prognostic biomarkers in patients with focal segmental glomerulosclerosis

Background:

Focal segmental glomerulosclerosis (FSGS) is a type of nephrotic syndrome which is diagnosed by renal biopsy. Degree of the proteinuria, renal dysfunction, histologic findings and the response to therapy are some factors used for evaluating the prognosis of FSGS.

Objectives:

In the present study, we attempted to discover some protein candidates for disease prognosis related to glomerular filtration rate (renal dysfunction).

Patients and Methods:

Urine samples were collected from ten patients. Urine proteome was extracted and trypsinated. Digested peptides were separated and identified by nano-flow LC-MS/MS. Protein content were determined using label-free quantification method. Protein profiles were analyzed using supervised multivariate statistical method.

Results:

Output of a predictive model was 54 significant proteins of which ribonuclease 2 and haptoglobin had the greatest fold change in terms of overrepresentation and underrepresentation in patients with the best and worse prognosis, respectively. Complement and coagulation cascades were the only significant pathways which were impaired in FSGS.

Conclusions:

Urinary biomarkers can potentially be used as non-invasive prognostic markers. However these candidate biomarkers need further validation by an alternative method and in a larger cohort.

Dynamic changes of regulatory T cell and dendritic cell subsets in stable kidney transplant patients: a prospective analysis

INTRODUCTION

We aimed to identify immune status of the stable kidney allografts from the point of some cellular changes that may occur after transplantation.

MATERIALS AND METHODS

This study considered 57 patients with no rejection during the 6 months after transplantation. Flow cytometric frequencies of circulatory CD4+CD25+FoxP3+ and CD8+CD28- regulatory T cells (Treg) as well as myeloid dendritic cells type 1 (MDC1) and type 2 (MDC2) and plasmacytoid dendritic cells (PDC) were measured before transplantation and 2 weeks and 1, 3, and 6 months after transplantation. Using adjusted model of repeated measure analysis, we assessed the influence of different parameters on different cell subsets.

RESULTS

The mean number of Tregs and PDCs decreased 2 weeks after transplantation and then increased as they reached their values before transplantation within a few months after transplantation. The mean MDC1s increased during 2 weeks and then decreased to its before-transplantation values within 6 months. The frequency of Tregs (r = 0.90) and MDC1s (r = 0.75) at month 3 could strongly predict their frequencies at month 6. Different variables including family relationship between donor and recipient, glomerular filtration rate, and human leukocyte antigen antibody mismatch did not change the frequency of different cell subsets during the time.

CONCLUSIONS

The dynamism and circulatory changes in the frequency of Tregs and PDCs are opposite to MDCs after kidney transplantation. We describe these changes in a group of patients with stable graft; however, our study does not render any idea in patients with unstable or rejecting grafts.

Costs of Treatment after Renal Transplantation: Is it Worth to Pay More?

The primary aim of the study was to estimate costs of treatment for the first year after renal transplantation from the perspective of health insurance organizations in Iran. An Excel-based and a Monte Carlo model were developed to determine the treatment costs of current clinical practice in renal transplantation therapy (RTT). Inputs were derived from Ministry of Health and insurance organizations database, hospital and pharmacy records, clinical trials and local and international literature. According to the model, there were almost 17,000 patients receiving RTT in Iran, out of which about 2,200 patients underwent the operation within the study year (2011 - 2012; n = 2,200) The estimated first year total treatment cost after renal transplantation was almost $14,000,000. These costs corresponded to annual total cost per patient of almost $6500 for the payers. Renal transplantation therapy is almost fully reimbursed by government in Iran. However, regarding new expensive medicines, cost of medical expenditure is rapidly growing and becoming quite unaffordable for the government; therefore, out-of-pocket (OOP) payments are dramatically increasing over time. In order to improve reimbursement policy making under pressure of current budget constraints, the present study is providing decision makers with practical tools make it possible for them to easily compare budgetary impact of the current therapy strategy with the future financial consequences of purchasing newly proposed medicines. In other words having estimation of the current budget spending on RTT would help policy makers in making efficient resource allocation and decrease quite high OOP expenditures.

Urinary prognostic biomarkers and classification of IgA nephropathy by high resolution mass spectrometry coupled with liquid chromatography

IgA nephropathy is the most common cause of primary glomerulonephritis. There are different pathologic biopsy-based scoring systems in use, but there is no consensus among nephrologists yet regarding the best classification method. Our aim was to test urine proteomics as a non-invasive method for classification of IgA nephropathy. This aim was pursued by discovering novel prognostic protein biomarkers in urine, and linking them to pathogenesis of the disease through known signaling and metabolic pathways. 13 urine samples of the patients with biopsy-proven IgA nephropathy were analyzed via two proteomics approaches: nanoflow LC-MS/MS and GeLC-MS/MS. The results of label-free quantification were subjected to multivariate statistical analysis, which could classify patients into two groups, broadly corresponding to the primary and advance stages. The proteome classification correlated well with biopsy-based scoring systems, especially endocapillary hypercellularity score of the Oxford’s classification. Differentially excreted candidate proteins were found as potential prognostic biomarkers: afamin, leucine-rich alpha-2-glycoprotein, ceruloplasmin, alpha-1-microgolbulin, hemopexin, apolipoprotein A-I, complement C3, vitamin D-binding protein, beta-2-microglobulin, and retinol-binding protein 4. Pathway analysis suggested impairment of Extra Cellular Matrix (ECM)-Receptor Interaction pathways as well as activation of complement and coagulation pathway in progression of IgA nephropathy.

Budget impact analysis of conversion from cyclosporine to sirolimus as immunosuppressive medication in renal transplantation therapy

Objectives

The aim of this study was to determine budget impact of conversion from cyclosporine (CsA) to sirolimus (SRL) in renal transplant therapy (RTT) from the perspective of insurance organizations in Iran.

Methods

An Excel-based model was developed to determine cost of RTT, comparing current CsA based therapy to an mTOR inhibitor-based therapy regimen. Total cost included both cost of immunosuppressive agents and relative adverse events. The inputs were derived from database of Ministry of Health and insurance organizations, hospital and pharmacy based registries, and available literature that were varied through a one-way sensitivity analysis. According to the model, there were almost 17,000 patients receiving RTT in Iran, out of which about 2,200 patients underwent the operation within the study year. The model was constructed based on the results of a local RCT, in which test and control groups received CsA, SRL, and steroids over the first 3 months posttransplantation and, from the fourth month on, CsA, mycophenolate mofetil (MMF), and steroids were used in the CsA group and SRL, MMF, and steroids were administered in the SRL group, respectively.

Results

The estimated cost of RTT with CsA was US$4,850,000 versus US$4,300,000 receiving SRL. These costs corresponded to the cost saving of almost US$550,000 for the payers.

Conclusion

To evaluate the financial consequence of adding mTOR inhibitors to the insurers’ formulary, in the present study, a budget impact analysis was conducted on sirolimus. Fewer cases of costly adverse events along with lower required doses of MMF related to SRL based therapies were major reasons for this saving budgetary impact.

The frequency of HHV-8 infection in otherwise healthy blood donors as well as renal allograft recipients living in Iran

BACKGROUND

Different reports from Middle East countries demonstrated Kaposi's sarcoma (KS) in transplant population. This vascular malignancy occurs mostly among immunocompromised individuals. Human herpesvirus 8 (HHV-8) appears to be the causative factor for the development of this neoplasm. Transplant programs are concerned about the frequencies of HHV-8 infection either in general population or transplant patients.

METHODS

The current study was conducted in two phases. Firstly, we detected antibodies against HHV-8 in 790 otherwise healthy blood donors. Secondly, a total of 125 kidney allograft recipients evaluated as being seropositive for HHV-8. We utilized enzyme immunoassay (EIA) for serologic studies.

RESULTS

Among blood donors, the male to female ratio was 1.05 (405 vs. 385 ) while the mean age was 38.9 ± 11.7 years. The serostatus of none of these blood donors were positive for HHV-8. Among kidney recipients, the male to female ratio was 1.9 (82 vs. 43). The mean age was 39.01 ± 14.77 years. Two (1.6%) patients were seropositive for HHV-8.

CONCLUSION

The prevalence of HHV-8 infection among Iranians is likely to be low. Yet, owing to the evidence of this infection among kidney allograft recipients and its probable role in developing post- transplantation KS (PT-KS), further studies appear to be required to keep the various aspects of this infection under close surveillance.

Comparison of the Th1, IFN-γ secreting cells and FoxP3 expression between patients with stable graft function and acute rejection post kidney transplantation

There are limited clinical investigations identifying the percentage of T helper 1 (Th1) and T regulatory (Treg) cells in stable as well as rejected kidney allografts, a concept which needs to be more studied. The aim of our study was to compare the percentage of CD4+ IFN-γ+ cells, the number of IFN-γ secreting cells and the amount of FoxP3 expression in patients with or without stable graft function, to determine the roles of these immunological factors in stable and rejected renal allografts. In this prospective study, 3 months after transplantation 30 patients who received renal transplants from unrelated living donors were enrolled and divided into two groups, 20 patients with stable graft function and 10 patients with biopsy proven acute rejection. The percentage of Th1 CD4+ IFN-γ+ cells was determined on PBMC by flow cytometry and the number of IFN-γ secreting cells by ELISPOT method. Furthermore, FoxP3 expression of PBMCs was measured by Real Time PCR method. The results of these assessments in both groups were statistically analyzed by SPSS 14.0. Our results showed that the percentage of Th1 CD4+ IFN-γ+ cells and the number of IFN-γ secreting cells were significantly higher in the patients with acute rejection in comparison to the stable graft function group (p<0.001). In addition, the level of FoxP3 gene expression was higher in the group with stable graft compared to the acute rejection group. The higher percentage of CD4+ IFN-γ+Th1 subset and number of IFN-γ secreting cells and also the lower expression of Foxp3 could prone the patients to acute rejection episode post transplantation. By these preliminary data, it is suggested that monitoring of Th1 cells post transplantation, as an immunologic marker could predict the possibility of rejection episodes.

Prevalence and risk factors of hyperuricemia among kidney transplant recipients

Hyperuricemia is common in renal transplant patients (RTRs), especially those on cyclosporine (CsA)-based therapy. We conducted a retrospective study to determine the prevalence of hyperuricemia and its risk factors among RTRs. A total of 17,686 blood samples were obtained from 4,217 RTRs between April 2008 and January 2011. Hyperuricemia was defined as an uric acid level of ≥7.0 mg/dl in men and of ≥6 mg/dl in women that persisted for at least two consecutive tests. Majority (68.2%) of RTRs were normouricemic. Hyperuricemia was more frequent in younger and female RTRs. On multivariate logistic regression, we found high trough level of cyclosporine to be a risk factor for hyperuricemia. In addition, female gender, impaired renal function, and dyslipidemia (hypercholesterolemia, hypertriglyceridemia, and elevated LDL) were also associated with higher probability of hyperuricemia. Hyperuricemia is a common complication after renal transplantation. Risk factors implicated in post-transplant hyperuricemia include high trough level of cyclosporine, female gender, renal allograft dysfunction, and dyslipidemia.

Effects of Combined Lipoic Acid and Pyridoxine on Albuminuria, Advanced Glycation End-Products, and Blood Pressure in Diabetic Nephropathy

This study was designed to investigate the effects of combined administration of lipoic acid and pyridoxine on albuminuria, oxidative stress, blood pressure, serum advanced glycation end-products, nitric oxide (NO), and endothelin-1 in patients with diabetic nephropathy. Thirty-four patients were randomly assigned to either a supplement group or a placebo group. The patients in the supplement group received 800 mg lipoic acid and 80 mg pyridoxine daily for 12 weeks, whereas the placebo group received corresponding placebos. Urinary albumin, serum malondialdehyde (MDA), and systolic blood pressure decreased significantly in the supplement group compared to the placebo group (p < 0.05). Serum NO increased in the supplement group compared to the placebo group (p < 0.05). Serum pentosidine and carboxymethyl lysine decreased significantly in the supplement group at the end of week 12 compared to baseline (p < 0.05). No statistically significant differences were observed between the two groups in mean changes of serum endothelin-1, glucose, and diastolic blood pressure. The present study indicates that combined administration of lipoic acid and pyridoxine improves albuminuria in patients with diabetic nephropathy by reducing oxidative stress, advanced glycation end-products, and systolic blood pressure. The reduction in microalbuminuria may be of benefit in retarding the progression of diabetic nephropathy.

Delayed graft function (DGF) after living donor kidney transplantation: a study of possible explanatory factors

BACKGROUND

Delayed graft function (DGF), caused by failure of the kidney to function properly after transplantation, has a lower incidence rate in living donor transplantation compared to deceased donor transplantation. The aim of this study was to investigate the possible risk factors related to DGF in living donor transplantations.

MATERIAL/METHOD

A prospective, observational cohort study of patients undergoing living donor renal transplantation was designed. The incidence of DGF was investigated; the urine levels of neutrophil gelatinase-associated lipocalin (NGAL) and interleukin 18 (IL-18) were measured on the 1st and 3rd day after transplantation, and the relationships of DGF incidence and potential explanatory factors were studied.

RESULT

DGF was observed in 16.2% of patients. Preliminary univariate analyses showed that older donors, retransplantation, previous blood transfusion, and low urinary output could be eligible predictors for DGF. Analysis of the urinary biomarkers revealed an association between DGF incidence with the level of NGAL on the 1st day after transplantation, level of IL 18 on the 3rd post-operative day, and with the differences in urine NGAL levels measured in 2 samplings. Multivariate logistic regression analysis showed that only the differences between the 1st and 3rd days of urinary NGAL levels could remain in the final model.

CONCLUSIONS

Although, possibly due to living donor transplantation, none of the patient/donor characteristics could act as an explanatory factor for DGF; however, special attention is still required to target post-operation inflammation and oxidative stress, confirmed by relationship observed between DGF and urine NGAL levels on postoperative days.

Dynamic Changes of IFN-γ-producing Cells, TGF-β and Their Preidctive Value in Early Outcomees of Renal Transplantation

BACKGROUND

A growing body of evidence demonstrated an immune etiology as well as nonimmune mechanisms for episodes of clinical acute rejection and long-term allograft dysfunction.

OBJECTIVE

To investigate the correlation of IFN-γ-producing cells and TGF-β with incidence of clinical acute rejection in living-related and unrelated kidney allogarft recipients during the first post-transplant year.

METHODS

This multi-center study was performed on 57 kidney allograft recipients from living-related (n=20) and unrelated (n=37) donors between April 2011 and September 2012 and who were followed prospectively for a mean period of one year. Peripheral blood samples were collected from all patients pre-transplantation and at days 14, 30 and 90 after transplantation; PBMCs were used as responding cells in enzyme-linked immunosorbent spot (ELISPOT) assay to measure the frequency of IFN-γ-producing cells after stimulation with donor lymphocytes. Additionally, TGF-β levels were measured in cell culture supernatants of ELISPOT assay.

RESULTS

During the follow-up period, 45 (79%) patients were diagnosed with stable graft function (group A); 12 (21%) experienced clinical acute rejection episodes (group B). The frequency of IFN-γ-producing cells was significantly (p<0.001) higher in the rejection group in all three times after transplantation. Also, post-transplantation comparison for TGF-β showed a significantly (p<0.001) higher contents in group A vs. group B. Comparing the post-transplantation levels of TGF-β and mean numbers of IFN-γ- producing cells between groups A and B demonstrated a continuous increment in TGF-β and decreasing frequencies of IFN-γ-producing cells in group A vs. group B.

CONCLUSION

Serial post-transplantation monitoring of IFN-γ-producing donor reactive cells during the first months is a clinically feasible approach for identification of kidney allogarft recipients at risk for ongoing immune-mediated graft damage and later graft loss.

Sirolimus versus calcineurin inhibitor-based immunosuppressive therapy in kidney transplantation: a 4-year follow-up

INTRODUCTION

Sirolimus is the one of new immunosuppressants that may be a substitute to traditional drugs such as cyclosporine. We present our investigation on sirolimus-based immunosuppression in kidney transplant recipients as compared with cyclosporine-based immunosuppression.

MATERIALS AND METHODS

We enrolled 100 patients in an open-labeled randomized clinical trial at Shahid Labbafinejad Medical Center. The patients were assigned to one of the immunosuppressive groups to receive either sirolimus or cyclosporine in combination with mycophenolate mofetil and steroids. All kidney transplant recipients were followed up by for serum creatinine and glomerular filtration rate for 4 years.

RESULTS

There was no significant differences between the two groups regarding serum creatinine level and GFR until for years posttransplant; however, serum creatinine levels were significantly lower and the GFRs were higher in the sirolimus group after 3 and 4 years. The mean serum creatinine was 1.24 ± 0.28 mg/dL in the sirolimus group and 1.57 ± 0.33 mg/dL in the cyclosporine group at 4 years posttransplant (P = .02). Also, GFR was 79.8 ± 22.3 mL/min/1.73 m2 in the sirolimus group and 70.3 ± 23.6 mL/min/1.73 m2 in the cyclosporine group B (P = .04). Acute rejection was 1.7-fold higher in the cyclosporine group than in the sirolimus group.

CONCLUSIONS

Our study demonstrated that sirolimus in the immunosuppressive regimen of kidney transplant recipients had better outcomes regarding graft and patient survival. The effectiveness of sirolimus for kidney allograft recipients should be further assessed to be implemented from the first day after transplantation.

Incidence of malignancy after living kidney transplantation: a multicenter study from iran

Malignancy is a common complication after renal transplantation. However, limited data are available on post-transplant malignancy in living kidney transplantation. Therefore, we made a plan to evaluate the incidence and types of malignancies, association with the main risk factors and patient survival in a large population of living kidney transplantation. We conducted a large retrospective multicenter study on 12525 renal recipients, accounting for up to 59% of all kidney transplantation in Iran during 22 years follow up period. All information was collected from observation of individual notes or computerized records for transplant patients. Two hundred and sixty-six biopsy-proven malignancies were collected from 16 Transplant Centers in Iran; 26 different type of malignancy categorized in 5 groups were detected. The mean age of patients was 46.2±12.9 years, mean age at tumor diagnosis was 50.8±13.2 years and average time between transplantation and detection of malignancy was 50.0±48.4 months. Overall tumor incidence in recipients was 2%. Kaposis' sarcoma was the most common type of tumor. The overall mean survival time was 117.1 months (95% CI: 104.9-129.3). In multivariate analysis, the only independent risk factor associated with mortality was type of malignancy. This study revealed the lowest malignancy incidence in living unrelated kidney transplantation.