The localization and significance of regulatory T cells (Treg) in allograft rejection is of considerable clinical and immunological interest. We analyzed 80 human renal transplant biopsies (including seven donor biopsies) with a double immunohistochemical marker for the Treg transcription factor FOXP3, combined with a second marker for CD4 or CD8. Quantitative FOXP3 cell counts were performed and analyzed for clinical and pathologic correlates. FOXP3+ cells were present in the interstitium in acute cellular rejection (ACR) type I and II, at a greater density than in acute humoral rejection or CNI toxicity (p < 0.01). Most FOXP3 + cells were CD4 + (96%); a minority expressed CD8. FOXP3 + CD4 + cells were concentrated in the tubules (p < 0.001), suggesting a selective attraction or generation at that site. Considering only patients with ACR, a higher density of FOXP3 + correlated with HLA class II match (p = 0.03), but paradoxically with worse graft survival. We conclude that infiltration of FOXP3 + cells occurs in ACR to a greater degree than in humoral rejection, however, within the ACR group, no beneficial effect on outcome was evident. Tregs concentrate in tubules, probably contributing to FOXP3 mRNA in urine; the significance and pathogenesis of 'Treg tubulitis' remains to be determined.

Lupus nephritis (LN) is a kidney inflammatory disease caused by systemic lupus erythematosus (SLE). NLRP3 inflammasome activation is implicated in LN pathogenesis, suggesting its potential targets for LN treatment. Melatonin, an endogenous indoleamine, is considered an important multitasking molecule that has been reported to have anti-inflammatory effects by inhibiting nuclear factor-kappa B (NF-κB)-mediated inflammatory responses in vivo. This molecule has also protective effects against the activation of the inflammasomes and, in particular, the NLRP3 inflammasome. Thus, this work evaluated the effect of melatonin on morphological alteration and NLRP3 inflammasome activation in LN pristane mouse models. To evaluate the melatonin effects in these mice, we studied the renal cytoarchitecture by means of morphological analyses and immunohistochemical expression of specific markers related to oxidative stress, inflammation and inflammasome activation. Our results showed that melatonin attenuates pristane-induced LN through restoring of morphology and attenuation of oxidative stress and inflammation through a pathway that inhibited activation of NLRP3 inflammasome signaling. Our data clearly demonstrate that melatonin has protective activity on lupus nephritis in these mice that is highly associated with its effect on enhancing the Nrf2 antioxidant signaling pathway and decreasing renal NLRP3 inflammasome activation.

BackgroundTo investigate gene expression of podocyte-specific proteins in urine of diabetes and prediabetes subjects and the association of these proteins with albuminuria.MethodsFifteen controls, 19 prediabetes, and 67 diabetes subjects were included. Messenger RNA of nephrin, podocin, podocalyxin, synaptopodin, TRPC6, alpha-actinin-4, and TGF-β1 were measured using RT-PCR. Podocyte marker expression was correlated with albuminuria, glycemic control, and renal function. The diagnostic performance of the genes used to detect increased albuminuria was assessed using ROC curves and Poisson regressions.ResultsPodocyte marker expression was significantly higher in diabetic subjects. Urinary nephrin was correlated with increasing levels of albuminuria; risk of albuminuria increased by 20% for every one-unit increase in the log10 of nephrin mRNA. Nephrinuria was found in 53%, 71%, and 90% of normo-, micro-, and macroalbuminuric diabetes subjects, respectively (p = 0.023). Urinary nephrin, podocalyxin, TRPC6, podocin, and alpha actinin-4 were correlated with glycemic control and albuminuria but not with renal function.ConclusionsDiabetes subjects had higher urinary mRNA levels of podocyte proteins than nondiabetic subjects, even the normoalbuminuric patients. Nephrinuria was correlated with diabetic nephrophathy stage and predicted pathological albuminuria. Urinary mRNA levels of podocyte markers of prediabetic subjects did not differ from controls.

This longitudinal analysis corroborates the findings of previous cross-sectional studies, supporting the use of the P/C ratio as an accurate test to define critical levels of proteinuria.

BackgroundGlomerular filtration rate (GFR) is the best index of renal function, but age, gender and ethnicity can putatively affect its values. The aim of this study was to establish reference values for GFR in healthy Brazilian subjects while taking these factors into account.MethodsIn this cross-sectional study, GFR was measured by the 51Cr-EDTA single-injection method. GFR reference values were developed according to CLSI Guidelines for Defining, Establishing, and Verifying Reference Intervals in the Clinical Laboratory (CLSI C28 protocol).ResultsThe age range of the 285 healthy individuals was 19 to 70 years, 57% were females, and GFR was 106 ± 18 mL/min/1.73 m2. There was no difference between male and female GFRs (108 ± 18 vs. 104 ± 18 mL/min/1.73 m2 respectively, P = 0.134), and reference values were therefore developed from the pooled sample. GFR values were lower in subjects aged ≥45 years as compared with those younger than 45 years (98 ± 15 vs.112 ± 18 mL/min/1.73 m2, P < 0.001). Based on mean ± 2 SD, GFR reference values were 76 to 148 mL/min/1.73 m2 for subjects younger than 45 years and 68 to 128 mL/min/1.73 m2 for individuals older than 45 years, irrespective of gender.ConclusionThe age-adjusted reference intervals reported may be reliably adopted to evaluate kidney function, since they are based on recommended standards.

Coronary calcification was highly prevalent in these uraemic patients on chronic haemodialysis. A correlation was evidenced between CaCs and advanced age, but severity of the CAC score did not have an impact on 2-year mortality of this cohort.

Background Renal fibrosis is the result of the interaction of cellular and molecular pathways, which is induced by sustained glomerular injury and involves the podocytes and multiple profibrotic factors. In this study, we investigated the correlation of the mRNA expression of podocyte proteins and profibrotic factors with renal fibrosis measured in renal biopsies of patients with primary and secondary glomerulopathies. Methods Eighty-four adult patients with primary or secondary glomerular diseases and 12 controls were included. Demographic and clinical data were collected. Seventy-two percent of the renal biopsies were done less than one year from clinical disease manifestation. The quantification of the podocyte-associated mRNAs of alpha-actinin-4, podocin, and podocalyxin, as well as of the profibrotic factors TGF-β1, CTGF, and VEGF-A were quantified by real-time polymerase chain reaction. The percent positive area of renal fibrosis was measured by immunohistochemistry staining, using anti-CTGF and anti-HHF35 antibodies and unpolarized Sirius Red. Correlations between the expression of tissue mRNAs and the positive area of fibrosis for the measured markers were made by Spearman’s rank correlation coefficient. Results In relation to control biopsies, podocyte-specific proteins were downregulated in podocytopathies, in proliferative nephritis, in diabetic kidney disease (DRD), and in IgA nephropathy (IgAN). Messenger RNA of TGF-β1, CTGF, and VEGF-A was upregulated in patients with podocytopathies and in DRD but not in proliferative nephritis and IgAN. Tissue mRNA expression of TGF-β1, CTGF, and VEGF-A were strongly correlated with renal fibrosis, as measured by HHF35; however, the correlation, albeit significant, was moderate for Sirius Red and weak for CTGF. The percent positive area of renal fibrosis measured by Sirius Red was similar between podocytopathies and DRD and significantly higher in podocytopathies compared to IgAN or proliferative nephritis. Conclusions In patients with glomerular diseases, the mRNA of TGF-β1, CTGF, and VEGF-A correlated positively with the extent of renal fibrosis, and the positive area of fibrosis was larger in the podocytopathies and in DRD as measured by Sirius Red. The pathways connecting podocyte damage and activation of profibrotic factors to kidney tissue fibrosis need to be better investigated.

A insuficiência renal aguda (IRA) é uma condição clínica muito prevalente em pacientes internados em Unidades de Tratamento Intensivo (UTI). Conforme dados de Uchino et al.1 , 72,5% dos pacientes que desenvolveram IRA durante internação na UTI necessitaram de algum tipo de tratamento dialítico, e 80% das terapias dialíticas empregadas nestes pacientes foram contínuas. A preferência por métodos contínuos é determinada, principalmente, pela sua maior tolerância hemodinâmica 2 , derivada de uma remoção mais gradual de solutos e líquidos, assim permitindo menores variações na osmolaridade sangüínea e contínua adaptação do volume circulante 3-5 . As terapias contínuas de substituição renal (TSRC), como outras técnicas de depuração sangüínea, constituem-se em um sistema de circulação extracorpórea, composto por uma linha arterial e uma venosa, um filtro ou capilar de diálise e um cateter de duplo lúmen inserido em veia calibrosa. Este circuito deve permanecer sem coágulos de sangue e permeável para atingir um desempenho adequado, resultando em ótimo controle da homeostasia do paciente. A literatura relata que a coagulação do sistema é responsável, em 40% a 75% das vezes, pela suspensão da terapia dialítica 6 , sendo esta a principal desvantagem da TSRC 7 . A troca freqüente de capilares por trombose resulta em uma menor eficiência da terapia, podendo ocasionar anemia e necessidade de reposição de sangue, aumentando o trabalho de enfermagem e os custos do tratamento. Por outro lado, a utilização de algum proto- A heparina não fracionada (HNF) é o anticoagulante mais utilizado para as diferentes técnicas de diálise e, mais recentemente, as heparinas de baixo peso molecular (HBPM) têm se mostrado seguras e efetivas para TRSC. Em pacientes criticamente enfermos que freqüentemente têm contra-indicação para anticoagulação sistêmica, existe a alternativa da anticoagulção regional com citrato trissódico, método eficiente e seguro, se aplicado com controle metabólico estrito. A anticoagulação regional com HNF/protamina tem seu uso limitado, atualmente, por apresentar muitas complicações decorrentes de efeitos adversos da protamina. Na impossibilidade do paciente ser anticoagulado, ou se a anticoagulação regional com citrato não for disponível, a lavagem freqüente do circuito de diálise com solução salina é a única alternativa aplicável. Novas drogas ainda não disponíveis no Brasil, como prostaglandinas, hirudina recombinante, argatroban e nafamostat podem ser utilizadas em pacientes com contra-indicação para heparinização.UNITERMOS: Terapia contínua de substituição renal. Anticoagulação. Heparina de baixo peso molecular. Heparina não fracionada. Citrato trissódico.colo de anticoagulação para maximizar a sobrevida dos filtros aumenta significativamente o risco de episódios de sangramento nestes pacientes. O risco de eventos hemorrágicos é elevado, pois estes pacientes já apresentam, comumente, algum grau de coagulopatia e, freqüentemente, coagulação intravascular disseminada (CIVD) em contexto de sepse 8 , agravado pelo efeito ...