548 results found
Bos EMJ, Sangle SR, Wilhelmus S, et al., 2022, Use of Glomerular CD68+ Cells as a Surrogate Marker for Endocapillary Hypercellularity in Lupus Nephritis., Kidney Int Rep, Vol: 7, Pages: 841-847
Introduction: Lupus nephritis (LN) class III or IV is strongly related to patient mortality and morbidity. The interobserver agreement of endocapillary hypercellularity by routine light microscopy, one of the most important lesions determining whether class III or IV is present, is moderate. In IgA nephropathy (IgAN), the presence of glomerular CD68+ cells was found to be a good surrogate marker for endocapillary hypercellularity. We investigated whether the presence of glomerular CD68+ cells could serve as a surrogate marker for endocapillary hypercellularity as well in LN. Methods: A total of 92 LN biopsies were scored for the number of glomerular CD68+ cells using CD68 staining, including endocapillary hypercellularity and the activity index (AI). A new AI was calculated in which CD68+ cells replaced endocapillary hypercellularity. Clinical parameters were obtained from time of biopsy, 1 year after, and 2 years after. Results: The number of glomerular CD68+ cells significantly correlated with endocapillary hypercellularity. A cutoff value of 7 for the maximum number of CD68+ cells within 1 glomerulus in a biopsy yielded a sensitivity of 88% and a specificity of 67% for the presence of endocapillary hypercellularity. Both endocapillary hypercellularity and CD68+ cells correlated with renal function during follow-up. The current and the new AI correlated equally well with the clinical outcome. Conclusion: In LN, CD68+ cells can be used as a surrogate marker for endocapillary hypercellularity.
Prendecki M, McAdoo SP, Turner-Stokes T, et al., 2022, Glomerulonephritis and autoimmune vasculitis are independent of P2RX7 but may depend on alternative inflammasome pathways., Journal of Pathology, ISSN: 0022-3417
P2RX7, an ionotropic receptor for extracellular ATP, is expressed on immune cells, including macrophages, monocytes and dendritic cells and is up-regulated on non-immune cells following injury. P2RX7 plays a role in many biological processes, including production of pro-inflammatory cytokines such as IL-1β via the canonical inflammasome pathway. P2RX7 has been shown to be important in inflammation and fibrosis and may also play a role in autoimmunity. We have developed and phenotyped a novel P2RX7 knock-out (KO) inbred rat strain and taking advantage of the human-resembling unique histopathological features of rat models of glomerulonephritis, we induced three models of disease: nephrotoxic nephritis, experimental autoimmune glomerulonephritis, and experimental autoimmune vasculitis. We found that deletion of P2RX7 does not protect rats from models of experimental glomerulonephritis or the development of autoimmunity. Notably, treatment with A-438079, a P2RX7 antagonist, was equally protective in WKY WT and P2RX7 KO rats, revealing its 'off-target' properties. We identify a novel ATP/P2RX7/K+ efflux-independent and caspase-1/8-dependent pathway for production of IL-1β in rat dendritic cells, which was absent in macrophages. Taken together, these results comprehensively establish that inflammation and autoimmunity in glomerulonephritis is independent of P2RX7 and reveals the off-target properties of drugs previously known as selective P2RX7 antagonists. Rat mononuclear phagocytes may be able to utilise an 'alternative inflammasome' pathway to produce IL-1β independently of P2RX7, which may account for the susceptibility of P2RX7 KO rats to inflammation and autoimmunity in glomerulonephritis. This article is protected by copyright. All rights reserved.
Tempest-Roe S, Prendecki M, McAdoo S, et al., 2022, Inhibition of spleen tyrosine kinase decreases donor specific antibody levels in a rat model of sensitization, Scientific Reports, Vol: 12, ISSN: 2045-2322
Antibody mediated rejection is a major cause of renal allograft loss. Circulating preformed donor specific antibodies (DSA) can result as a consequence of blood transfusion, pregnancy or prior transplantation. Current treatment strategies are limited due to partial or transient efficacy, adverse side-effects or patient unsuitability. Previous in vivo studies exploring autoimmune diseases have shown that spleen tyrosine kinase (SYK) signalling is involved in the development of pathogenic autoantibody. The role of SYK in allogenic antibody production is unknown, and we investigated this in a rodent model of sensitization, established by the transfusion of F344 whole blood into LEW rats. Two-week treatment of sensitized rats with selective SYK inhibitor fostamatinib strongly blocked circulating DSA production without affecting overall total immunoglobulin levels, and inhibition was sustained up to 5 weeks post-completion of the treatment regimen. Fostamatinib treatment did not affect mature B cell subset or plasma cell levels, which remained similar between non-treated controls, vehicle treated and fostamatinib treated animals. Our data indicate fostamatinib may provide an alternative therapeutic option for patients who are at risk of sensitization following blood transfusion while awaiting renal transplant.
Gilmore A, Wilson H, Cairns T, et al., 2022, Immune gene expression and functional networks in distinct lupus nephritis classes, Lupus Science & Medicine, Vol: 9, ISSN: 2053-8790
Objective: To explore the utility of the NanoString platform in elucidating kidney immune transcripts for class III, IV and V lupus nephritis (LN) using a retrospective cohort of formalin-fixed paraffin-embedded (FFPE) kidney biopsy tissue.Methods: Immune gene transcript analysis was performed using the NanoString nCounter platform on RNA from LN (n=55), thin basement membrane disease (TBM, n=14) and membranous nephropathy (MN, n=9) FFPE kidney biopsy tissue. LN samples consisted of single class III (n=11), IV (n=23) and V (n=21) biopsies with no mixed lesions. Differential gene expression was performed with NanoString nSolver, with visualisations of volcano plots and heatmaps generated in R. Significant transcripts were interrogated to identify functional networks using STRING and Gene ontogeny terms. Results: In comparison to TBM, we identified 52 significantly differentially expressed genes common to all three LN classes. Pathway analysis showed enrichment for type I interferon (IFN) signalling, complement and MHC II pathways, with most showing the highest expression in class IV LN. Our class IV LN biopsies also showed significant upregulation of NF-κB signalling and immunological enrichment in comparison to class V LN biopsies. Transcripts from the type I IFN pathway distinguished class V LN from MN. Conclusion: Our whole kidney section transcriptomic analysis provided insights into the molecular profile of class III, IV and V LN. The data highlighted important pathways common to all three classes and pathways enriched in our class IV LN biopsies. The ability to reveal molecular pathways in LN using FFPE whole biopsy sections could have clinical utility in treatment selection for LN.
Podos S, Nester C, Appel G, et al., 2022, Clinical and biomarker characteristics of patients with C3G enrolled in two phase II studies investigating the factor D inhibitor danicopan, Publisher: PERGAMON-ELSEVIER SCIENCE LTD, Pages: 148-148, ISSN: 0161-5890
Tang X, VanBeek C, Haas M, et al., 2021, Cell-Mediated Glomerulonephritis Without Immune Complexes in Native Kidney Biopsies: A Report of 7 Cases., Am J Kidney Dis
We report 7 native kidney biopsies with diffuse endocapillary hypercellularity without immune deposits, affecting 5 women and 2 men aged 52-85 years. All patients had acute kidney injury, and 4 had nephrotic-range proteinuria. Comorbidities included breast cancer in 2, pancreatitis in 1, and para-aortic lymphadenopathy and bilateral carpal tunnel syndrome in 1. Kidney biopsies were characterized by predominant T-cell and CD68-positive macrophage infiltration in glomerular capillaries without deposits. Coexisting lesions included small cellular crescents in 5, mild peritubular capillaritis in 1, mononuclear cell intimal arteritis in 1, acute tubulointerstitial nephritis in 4, and mild arteriolosclerosis in 1. During the mean follow-up duration of 24.8 months, 4 patients showed partial or complete initial remission in response to immunosuppression. However, 2 deteriorated when prednisone was rapidly tapered (1 of them achieved subsequent remission with increased prednisone). Three patients developed kidney failure. We propose that this unusual pattern of injury is mediated by abnormal cell-mediated immune response. The underlying causes and pathogenesis of this cell-mediated glomerulonephritis will require further study.
Fakhouri F, Walker P, Dixon B, et al., 2021, A phase 2 study to evaluate the efficacy and safety of pegcetacoplan in the treatment of patients with posttransplant recurrence of C3G or IC-MPGN, Publisher: E M H SWISS MEDICAL PUBLISHERS LTD, Pages: 28S-28S, ISSN: 1424-7860
Fakhouri F, Dixon B, Pickering M, et al., 2021, Phase 3, randomized, multicenter study to evaluate the efficacy and safety of pegcetacoplan in treatment of C3G or IC-MPGN, Publisher: E M H SWISS MEDICAL PUBLISHERS LTD, Pages: 33S-33S, ISSN: 1424-7860
Wong EKS, Marchbank KJ, Lomax-Browne H, et al., 2021, C3 Glomerulopathy and Related Disorders in Children: Etiology-Phenotype Correlation and Outcomes, CLINICAL JOURNAL OF THE AMERICAN SOCIETY OF NEPHROLOGY, Vol: 16, Pages: 1639-1651, ISSN: 1555-9041
Dixon BP, Fakhouri F, Pickering MC, et al., 2021, PHASE 3, RANDOMIZED, MULTICENTER STUDY TO EVALUATE THE EFFICACY AND SAFETY OF PEGCETACOPLAN IN TREATMENT OF C3G OR IC-MPGN, Publisher: SPRINGER, Pages: 3399-3400, ISSN: 0931-041X
Prendecki M, Gulati K, Turner-Stokes T, et al., 2021, Characterisation of an enhanced preclinical model of experimental MPO-ANCA autoimmune vasculitis, Journal of Pathology, Vol: 255, Pages: 107-119, ISSN: 0022-3417
Experimental autoimmune vasculitis (EAV) is a model of antineutrophil cytoplasm antibody (ANCA)-associated vasculitis (AAV) induced by immunisation of susceptible rat strains with myeloperoxidase (MPO). Animals develop circulating MPO-ANCA, pulmonary haemorrhage and glomerulonephritis, although renal injury is mild and recovers spontaneously without treatment. In this study we aimed to augment the severity of glomerulonephritis. Following induction of EAV on day 0, a sub-nephritogenic dose of nephrotoxic serum (NTS) containing heterologous antibodies to glomerular basement membrane was administered on day 14. This resulted in a significant increase in disease severity at day 28 compared to MPO immunisation alone - with more urinary abnormalities, infiltrating glomerular leucocytes, and crescent formation that progressed to glomerular and tubulointerstitial scarring by day 56, recapitulating important features of human disease. Importantly, the glomerulonephritis remained pauci-immune, and was strictly dependent on the presence of autoimmunity to MPO, as there was no evidence of renal disease following administration of sub-nephritogenic NTS alone or after immunisation with a control protein in place of MPO. Detailed phenotyping of glomerular leucocytes identified an early infiltrate of non-classical monocytes following NTS administration that, in the presence of autoimmunity to MPO, may initiate the subsequent influx of classical monocytes which augment glomerular injury. We also showed that this model can be used to test novel therapeutics by using a small molecule kinase inhibitor (fostamatinib) that rapidly attenuated both glomerular and pulmonary injury over a four-day treatment period. We believe that this enhanced model of MPO-AAV will prove useful for the study of glomerular leucocyte behaviour and novel therapeutics in AAV in the future. This article is protected by copyright. All rights reserved.
Kidney Disease Improving Global Outcomes KDIGO Glomerular Diseases Work Group, 2021, KDIGO 2021 clinical practice Guideline for the management of glomerular diseases., Kidney International, Vol: 100, Pages: S1-S276, ISSN: 0085-2538
This guideline is published as a supplement supported by KDIGO. The development and publication of this guideline are strictly funded by KDIGO, and neither KDIGO nor its guideline Work Group members sought or received monies or fees from corporate or commercial entities in connection with this work. The opinions or views expressed in this professional education supplement are those of the authors and do not necessarily reflect the opinions or recommendations of the International Society of Nephrology or Elsevier. Dosages, indications, and methods of use for products that are referred to in the supplement by the authors may reflect their clinical experience or may be derived from the professional literature or other clinical sources. Because of the differences between in vitro and in vivo systems and between laboratory animal models and clinical data in humans, in vitro and animal data may not necessarily correlate with clinical results.
Rovin BH, Adler SG, Barratt J, et al., 2021, Executive summary of the KDIGO 2021 Guideline for the Management of Glomerular Diseases, KIDNEY INTERNATIONAL, Vol: 100, Pages: 753-779, ISSN: 0085-2538
Dotz V, Visconti A, Lomax-Browne HJ, et al., 2021, O- and N-glycosylation of serum immunoglobulin A is associated with IgA nephropathy and glomerular function., Journal of the American Society of Nephrology, Vol: 32, Pages: 1-12, ISSN: 1046-6673
BACKGROUND: IgA nephropathy (IgAN) is the most common primary glomerular disease worldwide and is a leading cause of renal failure. The disease mechanisms are not completely understood, but a higher abundance of galactose-deficient IgA is recognized to play a crucial role in IgAN pathogenesis. Although both types of human IgA (IgA1 and IgA2) have several N-glycans as post-translational modification, only IgA1 features extensive hinge-region O-glycosylation. IgA1 galactose deficiency on the O-glycans is commonly detected by a lectin-based method. To date, limited detail is known about IgA O- and N-glycosylation in IgAN. METHODS: To gain insights into the complex O- and N-glycosylation of serum IgA1 and IgA2 in IgAN, we used liquid chromatography-mass spectrometry (LC-MS) for the analysis of tryptic glycopeptides of serum IgA from 83 patients with IgAN and 244 age- and sex-matched healthy controls. RESULTS: Multiple structural features of N-glycosylation of IgA1 and IgA2 were associated with IgAN and glomerular function in our cross-sectional study. These features included differences in galactosylation, sialylation, bisection, fucosylation, and N-glycan complexity. Moreover, IgA1 O-glycan sialylation was associated with both the disease and glomerular function. Finally, glycopeptides were a better predictor of IgAN and glomerular function than galactose-deficient IgA1 levels measured by lectin-based ELISA. CONCLUSIONS: Our high-resolution data suggest that IgA O- and N-glycopeptides are promising targets for future investigations on the pathophysiology of IgAN and as potential noninvasive biomarkers for disease prediction and deteriorating kidney function.
Singh S, Roufosse C, Smith A, et al., 2021, An Audit of Electron Microscopic Evaluation of Native Renal Biopsies, Publisher: WILEY, Pages: S47-S47, ISSN: 0022-3417
Medjeral-Thomas NR, Cook HT, Pickering MC, 2021, Complement activation in IgA nephropathy, Springer Seminars in Immunopathology, Vol: 43, Pages: 679-690, ISSN: 1863-2297
IgA nephropathy pathogenesis is incompletely understood, and this limits the development of disease-specific biomarkers and effective therapies. Evidence of complement activity in IgA nephropathy is well established. However, a growing body of research indicates complement activity is an important contributor to IgA nephropathy pathology. In particular, multiple associations have been identified between complement alternative, lectin and terminal pathway proteins and IgA nephropathy severity. Recently, we have also gained insight into possible mechanisms that could link glomerular IgA deposition, complement activity, glomerular inflammation and disease severity. Ongoing clinical trials of therapeutic complement inhibitors will provide insight into the importance of complement activity to IgA nephropathy pathogenesis. Further research into mechanisms of complement activity is essential to improving our understanding and management of patients with IgA nephropathy.
Vallant N, Wolfhagen N, Sandhu B, et al., 2021, A Comparison of Pulsatile Hypothermic and Normothermic Ex Vivo Machine Perfusion in a Porcine Kidney Model, TRANSPLANTATION, Vol: 105, Pages: 1760-1770, ISSN: 0041-1337
Toulza F, Dominy K, Beadle J, et al., 2021, GENE EXPRESSION ANALYSIS USING QRT-PCR IN THE DIAGNOSIS OF ANTIBODY-MEDIATED REJECTION IN RENAL TRANSPLANT BIOPSIES, Publisher: WILEY, Pages: 290-290, ISSN: 0934-0874
Garcia E, Lightley J, Kumar S, et al., 2021, Application of direct stochastic optical reconstruction microscopy (dSTORM) to the histological analysis of human glomerular disease, Publisher: SPRINGER, Pages: S142-S142, ISSN: 0945-6317
Kousios A, Mcadoo S, Blakey S, et al., 2021, Masked crystalline light chain tubulopathy and podocytopathy with focal segmental glomerulosclerosis: a rare MGRS-associated renal lesion, Histopathology, Vol: 79, Pages: 265-268, ISSN: 1365-2559
Monoclonal Gammopathy of Renal Significance (MGRS) encompasses a wide spectrum of histopathology. Characterizing rare forms of MGRS-related renal pathology remains work in progress. Light chain crystalline podocytopathy in the context of MGRS, either in isolation or combined with proximal tubulopathy (LCPT) has rarely been described. Unravelling MGRS pathologies is critical for patient management and often requires ancillary techniques for antigen retrieval to demonstrate light chain (LC) restriction on immunofluorescence (IF).
Roufosse C, Cook H, Dominy K, et al., 2021, Diagnostic application of transcripts associated with antibody-mediated rejection in kidney transplant biopsies, Nephrology Dialysis Transplantation, ISSN: 0931-0509
BackgroundThe diagnosis of antibody-mediated rejection (AMR) is reached using the Banff Classification for Allograft Pathology, which now includes gene expression analysis. In this study, we investigate the application of “Increased Expression Of Thoroughly Validated Gene Transcripts/Classifiers Strongly Associated With AMR” as a diagnostic criteria.MethodWe used qRT-PCR for 10 genes associated with AMR in a retrospective cohort of 297 transplant biopsies, including biopsies that met the full diagnostic criteria for AMR, even without molecular data (AMR, n = 27); biopsies that showed features of AMR, but that would only meet criteria for AMR with increased transcripts (AMRsusp, n = 49) and biopsies that would never meet criteria for AMR (No-AMR, n = 221).ResultsA 10-gene AMR score trained by a receiver-operating characteristic to identify AMR found 16 cases with a high score amongst the AMRsusp cases (AMRsusp-high) that had significantly worse graft survival than those with a low score (AMRsusp-low) (n = 33). In both univariate and multivariate Cox regression analysis, the AMR 10-gene score was significantly associated with an increased hazard ratio for graft loss in the AMRsusp group (HR 1.109, p = 0.004 and HR 1.138, p = 0.012), but not in the whole cohort. Net reclassification index and integrated discrimination improvement analyses demonstrated improved risk classification and superior discrimination respectively for graft loss when considering the gene score in addition to histological and serological data, but only in the AMRsusp group, not the whole cohort.ConclusionsThis study provides evidence that a gene score strongly associated with AMR helps identify cases at higher risk of graft loss in biopsies that are suspicious for AMR but don’t meet full criteria.
Garcia E, Lightley J, Kumar S, et al., 2021, Application of direct stochastic optical reconstruction microscopy (dSTORM) to the histological analysis of human glomerular disease, JOURNAL OF PATHOLOGY CLINICAL RESEARCH, Vol: 7, Pages: 438-445
Nester C, Podos S, Hogan J, et al., 2021, CLINICAL AND BIOMARKER CHARACTERISTICS OF PATIENTS WITH C3G OR IC-MPGN ENROLLED IN TWO PHASE II STUDIES INVESTIGATING THE FACTOR D INHIBITOR DANICOPAN, 58th Congress of the European-Renal-Association (ERA)-European-Dialysis-and-Transplant-Association (EDTA), Publisher: OXFORD UNIV PRESS, Pages: 149-149, ISSN: 0931-0509
Medjeral-Thomas NR, Pickering MC, Cook HT, 2021, Complement and kidney disease, new insights., Curr Opin Nephrol Hypertens, Vol: 30, Pages: 310-316
PURPOSE OF REVIEW: In this review, we discuss recent studies showing the importance of the complement pathway in kidney disease. RECENT FINDINGS: Recent findings in C3 glomerulopathy (C3G) include: acute postinfectious glomerulonephritis is characterised by the presence of antifactor B antibodies; human leukocyte antigen type, but not rare complement gene variation, is associated with primary immunoglobulin-associated membranoproliferative GN and C3G. Immunohistochemistry in C3G shows that factor H related protein 5 (FHR5) is the most prevalent complement protein and correlates with kidney function. A multicentre study supported the use of mycophenolate mofetil (MMF) in C3G even after a propensity matching analysis. In immunoglobulin A nephropathy (IgAN) several studies have emphasised the importance of complement. Imbalances of circulating FH and FHR1 and FHR5, which interfere with the regulatory functions of FH, associate with IgAN. Immunohistochemistry has shown associations between glomerular FHR5 deposition and C3 activation; glomerular FHR5 associated with clinical markers of IgAN severity. Data also suggest the lectin complement pathway contributes to IgAN severity. We also discuss complement activation in thrombotic microangiopathy and other kidney diseases. SUMMARY: Complement activity can be detected in a wide range of kidney diseases and this provides pathogenic insight and potential for therapy with the ongoing development of several drugs directed at complement activation.
Malik TH, Gitterman DP, Lavin DP, et al., 2021, Gain-of-function factor H–related 5 protein impairs glomerular complement regulation resulting in kidney damage, Proceedings of the National Academy of Sciences, Vol: 118, Pages: 1-9, ISSN: 0027-8424
Genetic variation within the factor H–related (FHR) genes is associated with the complement-mediated kidney disease, C3 glomerulopathy (C3G). There is no definitive treatment for C3G, and a significant proportion of patients develop end-stage renal disease. The prototypical example is CFHR5 nephropathy, through which an internal duplication within a single CFHR5 gene generates a mutant FHR5 protein (FHR5mut) that leads to accumulation of complement C3 within glomeruli. To elucidate how abnormal FHR proteins cause C3G, we modeled CFHR5 nephropathy in mice. Animals lacking the murine factor H (FH) and FHR proteins, but coexpressing human FH and FHR5mut (hFH-FHR5mut), developed glomerular C3 deposition, whereas mice coexpressing human FH with the normal FHR5 protein (hFH-FHR5) did not. Like in patients, the FHR5mut had a dominant gain-of-function effect, and when administered in hFH-FHR5 mice, it triggered C3 deposition. Importantly, adeno-associated virus vector-delivered homodimeric mini-FH, a molecule with superior surface C3 binding compared to FH, reduced glomerular C3 deposition in the presence of the FHR5mut. Our data demonstrate that FHR5mut causes C3G by disrupting the homeostatic regulation of complement within the kidney and is directly pathogenic in C3G. These results support the use of FH-derived molecules with enhanced C3 binding for treating C3G associated with abnormal FHR proteins. They also suggest that targeting FHR5 represents a way to treat complement-mediated kidney injury.
Nikolopoulou A, Teixeira C, Cook H, et al., 2021, Membranous nephropathy associated with viral infection, Clinical Kidney Journal, Vol: 14, Pages: 876-883, ISSN: 2048-8505
BackgroundMembranous nephropathy (MN) can be associated with hepatitis infection and less commonly with human immunodeficiency virus (HIV) infection. The significance of anti-phospholipase A2 receptor (PLA2R) and anti-thrombospondin type 1 domain-containing 7A (THSD7A) antibodies in this setting is unclear.MethodsWe describe the clinical, histopathological and outcome data of 19 patients with MN and hepatitis B virus (HBV), hepatitis C virus (HCV) or HIV infection identified through our renal biopsy database and the association with anti-PLA2R antibodies and anti-THSD7A antibodies.ResultsThe cohort consisted of 19 patients, 8 male and 11 female, with a median age of 42 years (range 23–74). HBV infection was found in six cases, HCV in four and HIV in nine (two HIV patients had HBV co-infection and one HCV co-infection). PLA2R staining on biopsy was positive in 10/19 patients: 4 with HBV-MN, 3 with HCV-MN and 3 with HIV-MN and circulating anti-PLA2R antibodies were detected in 7/10 cases. THSD7A staining on biopsy was positive in three PLA2R-negative cases, one with HBV-MN and two with HIV-MN. Mean proteinuria was higher in the PLA2R-positive group and the median urinary protein:creatinine ratio (uPCR) was 963 mg/mmol (range 22–2406) compared with the PLA2R-negative group [median uPCR 548 mg/mmol (range 65–1898); P = 0.18 Mann–Whitney]. Spontaneous remission occurred in 6/19 patients and after-treatment remission occurred in 7/11 patients. Renal function was preserved in all but two patients who required haemodialysis 2 and 11 years from diagnosis.ConclusionsWe describe a cohort of patients with MN associated with viral infection, including rare cases of HIV-MN with PLA2R and THSD7A positivity. The mechanism of coincidental or viral-related MN needs to be investigated further.
Gilmore AC, Zhang Y, Cook HT, et al., 2021, Complement activity is regulated in C3 glomerulopathy by IgG-factor H fusion proteins with and without properdin targeting domains, Kidney International, Vol: 99, Pages: 396-404, ISSN: 0085-2538
C3 glomerulopathy is characterized by accumulation of complement C3 within glomeruli. Causes include, but are not limited to, abnormalities in factor H, the major negative regulator of the complement alternative pathway. Factor H-deficient (Cfh-/-) mice develop C3 glomerulopathy together with a reduction in plasma C3 levels. Using this model, we assessed the efficacy of two fusion proteins containing the factor H alternative pathway regulatory domains (FH1-5) linked to either a non-targeting mouse immunoglobulin (IgG-FH1-5) or to an anti-mouse properdin antibody (Anti-P-FH1-5). Both proteins increased plasma C3 and reduced glomerular C3 deposition to an equivalent extent, suggesting that properdin-targeting was not required for FH1-5 to alter C3 activation in either plasma or glomeruli. Following IgG-FH1-5 administration, plasma C3 levels temporally correlated with changes in factor B levels whereas plasma C5 levels correlated with changes in plasma properdin levels. Notably, the increases in plasma C5 and properdin levels persisted for longer than the increases in C3 and factor B. In Cfh-/- mice IgG-FH1-5 reduced kidney injury during accelerated serum nephrotoxic nephritis. Thus, our data demonstrate that IgG-FH1-5 restored circulating alternative pathway activity and reduced glomerular C3 deposition in Cfh-/- mice and that plasma properdin levels are a sensitive marker of C5 convertase activity in factor H deficiency. The immunoglobulin conjugated FH1-5 protein, through its comparatively long plasma half-life, may be a potential therapy for C3 glomerulopathy.
Canney M, Barbour SJ, Zheng Y, et al., 2021, Quantifying Duration of Proteinuria Remission and Association with Clinical Outcome in IgA Nephropathy., J Am Soc Nephrol, Vol: 32, Pages: 436-447
BACKGROUND: On the basis of findings of observational studies and a meta-analysis, proteinuria reduction has been proposed as a surrogate outcome in IgA nephropathy. How long a reduction in proteinuria needs to be maintained to mitigate the long-term risk of disease progression is unknown. METHODS: In this retrospective multiethnic cohort of adult patients with IgA nephropathy, we defined proteinuria remission as a ≥25% reduction in proteinuria from the peak value after biopsy, and an absolute reduction in proteinuria to <1 g/d. The exposure of interest was the total duration of first remission, treated as a time-varying covariate using longitudinal proteinuria measurements. We used time-dependent Cox proportional hazards regression models to quantify the association between the duration of remission and the primary outcome (ESKD or a 50% reduction in eGFR). RESULTS: During a median follow-up of 3.9 years, 274 of 1864 patients (14.7%) experienced the primary outcome. The relationship between duration of proteinuria remission and outcome was nonlinear. Each 3 months in sustained remission up to approximately 4 years was associated with an additional 9% reduction in the risk of disease progression (hazard ratio [HR], 0.91; 95% confidence interval [95% CI], 0.89 to 0.93). Thereafter, each additional 3 months in remission was associated with a smaller, nonsignificant risk reduction (HR, 0.99; 95% CI, 0.96 to 1.03). These findings were robust to multivariable adjustment and consistent across clinical and histologic subgroups. CONCLUSIONS: Our findings support the use of proteinuria as a surrogate outcome in IgA nephropathy, but additionally demonstrate the value of quantifying the duration of proteinuria remission when estimating the risk of hard clinical endpoints.
Rovin BH, Caster DJ, Cattran DC, et al., 2021, Management and treatment of glomerular diseases (part 2): Conclusions from a kidney disease: Improving global outcomes (kdigo) controversies conference, Nephrology (Saint-Petersburg), Vol: 25, Pages: 96-119, ISSN: 1561-6274
In November 2017, the Kidney Disease: Improving Global Outcomes (KDIGO) initiative brought a diverse panel of experts in glomerular diseases together to discuss the 2012 KDIGO glomerulonephritis guideline in the context of new developments and insights that had occurred over the years since its publication. During this KDIGO Controversies Conference on Glomerular Diseases, the group examined data on disease pathogenesis, biomarkers, and treatments to identify areas of consensus and areas of controversy. This report summarizes the discussions on primary podocytopathies, lupus nephritis, anti-neutrophil cytoplasmic antibody-associated nephritis, complement mediated kidney diseases, and monoclonal gammopathies of renal significance.
Dattani R, Corbett RW, Galliford J, et al., 2020, The Effect of Kidney Biopsy on Glomerular Filtration Rate: A Frequent Patient Concern, AMERICAN JOURNAL OF NEPHROLOGY, Vol: 51, Pages: 903-906, ISSN: 0250-8095
This data is extracted from the Web of Science and reproduced under a licence from Thomson Reuters. You may not copy or re-distribute this data in whole or in part without the written consent of the Science business of Thomson Reuters.