Kidney Outcomes and Preservation of Kidney Function With Obinutuzumab in Patients With Lupus Nephritis: A Post Hoc Analysis of the NOBILITY Trial.

OBJECTIVE: To determine whether adding obinutuzumab to standard-of-care lupus nephritis (LN) therapy could improve the likelihood of long-term preservation of kidney function and do so with less glucocorticoids. METHODS: Post hoc analyses of the phase II NOBILITY trial were performed. Time to unfavorable kidney outcome (a composite of treatment failure, doubling of serum creatinine, or death), LN flare, first 30% and 40% declines in estimated glomerular filtration rate (eGFR) from baseline, and chronic eGFR slope during the trial were compared between patients with active LN who were randomized to take obinutuzumab (n = 63) or placebo (n = 62) in combination with mycophenolate mofetil and glucocorticoids. The number of patients who achieved complete renal response (CRR) on 7.5 mg or less per day of prednisone was also determined. RESULTS: Obinutuzumab reduced the risk of developing the composite kidney outcome by 60%, LN flare by 57%, and first eGFR decline of 30% or 40% by 80% and 91%, respectively. Patients receiving obinutuzumab had a significantly slower decline in eGFR than patients receiving placebo, with an annualized eGFR slope advantage of 4.1 ml/min/1.73 m2 /year (95% confidence interval 0.14-8.08). Overall, 38% of patients receiving obinutuzumab compared with 16% of patients receiving placebo achieved CRR at week 76 while receiving 7.5 mg or less per day of prednisone (P < 0.01); at week 104, the difference did not achieve significance (38% vs 22%; P = 0.06). CONCLUSION: Post hoc analyses of NOBILITY demonstrated that compared with standard-of-care therapy, obinutuzumab treatment resulted in superior preservation of kidney function and prevention of LN flares. More patients achieved CRR at week 76 with less glucocorticoid use in the obinutuzumab group.

Maintenance of remission of ANCA vasculitis by rituximab based on B cell repopulation versus serological flare: a randomised trial.

OBJECTIVE: To compare two long-term remission maintenance strategies for antineutrophil cytoplasmic antibody (ANCA) vasculitis. METHODS: We conducted a prospective, single-centre, open-label, randomised controlled trial of patients with ANCA vasculitis in remission after completing at least 2 years of fixed-schedule rituximab. In the B cell arm, rituximab was reinfused upon B cell repopulation; in the ANCA arm, rituximab was reinfused upon significant rise in ANCA level. Evaluations were conducted every 3 months. The primary endpoint was clinical relapse, defined as a modified BVAS/WG >0 by 36 months. Secondary endpoints included serious adverse events (SAEs) and rituximab exposure. RESULTS: 115 patients were enrolled. Median follow-up time was 4.1 years (IQR 2.5-5.0). By Kaplan-Meier analysis, 4.1% (95% CI 1.0 to 15.6) of patients had a clinical relapse in the B cell arm, compared with 20.5% (95% CI 11.9 to 34.1) in the ANCA arm, at 3 years after study entry (log-rank p=0.045). Total SAEs, including infectious SAEs, and deaths did not differ. The number of SAEs due to COVID-19 was higher in the B cell arm (p=0.049). In the B cell arm, patients received a mean of 3.6 (SD 2.4) infusions (3.6 g) per person over the median study follow-up time of 4.1 years, compared with 0.5 (SD 1.4) infusions (0.5 g) per patient in the ANCA arm (p<0.001). CONCLUSIONS: Rituximab dosed for B cell repopulation results in fewer clinical relapses than when dosed for a rise in ANCA level in maintenance of remission for ANCA vasculitis. Overall safety was equivalent; SAEs due to COVID-19 and rituximab exposure were higher with the B cell strategy. TRIAL REGISTRATION NUMBER: NCT02749292.

Phase II Randomized Trial of Rituximab Plus Cyclophosphamide Followed by Belimumab for the Treatment of Lupus Nephritis.

OBJECTIVE: To assess the safety, mechanism of action, and preliminary efficacy of rituximab followed by belimumab in the treatment of refractory lupus nephritis (LN). METHODS: In a multicenter, randomized, open-label clinical trial, 43 patients with recurrent or refractory LN were treated with rituximab, cyclophosphamide (CYC), and glucocorticoids followed by weekly belimumab infusions until week 48 (RCB group), or treated with rituximab and CYC but no belimumab infusions (RC group). Patients were followed up until week 96. Percentages of total and autoreactive B cell subsets in the patients' peripheral blood were analyzed by flow cytometry. RESULTS: Treatment with belimumab did not increase the incidence of adverse events in patients with refractory LN. At week 48, a complete or partial renal response occurred in 11 (52%) of 21 patients receiving belimumab, compared to 9 (41%) of 22 patients in the RC group who did not receive belimumab (P = 0.452). Lack of improvement in or worsening of LN was the major reason for treatment failure. B cell depletion occurred in both groups, but the percentage of B cells remained lower in those receiving belimumab (geometric mean number of B cells at week 60, 53 cells/µl in the RCB group versus 11 cells/µl in the RC group; P = 0.0012). Percentages of total and autoreactive transitional B cells increased from baseline to week 48 in both groups. However, percentages of total and autoreactive naive B cells decreased from baseline to week 48 in the belimumab group compared to the no belimumab RC group (P = 0.0349), a finding that is consistent with the observed impaired maturation of naive B cells and enhanced censoring of autoreactive B cells. CONCLUSION: The addition of belimumab to a treatment regimen with rituximab and CYC was safe in patients with refractory LN. This regimen diminished maturation of transitional to naive B cells during B cell reconstitution, and enhanced the negative selection of autoreactive B cells. Clinical efficacy was not improved with rituximab and CYC in combination with belimumab when compared to a therapeutic strategy of B cell depletion alone in patients with LN.

Publisher Correction: The immune cell landscape in kidneys of patients with lupus nephritis.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

The immune cell landscape in kidneys of patients with lupus nephritis.

Lupus nephritis is a potentially fatal autoimmune disease for which the current treatment is ineffective and often toxic. To develop mechanistic hypotheses of disease, we analyzed kidney samples from patients with lupus nephritis and from healthy control subjects using single-cell RNA sequencing. Our analysis revealed 21 subsets of leukocytes active in disease, including multiple populations of myeloid cells, T cells, natural killer cells and B cells that demonstrated both pro-inflammatory responses and inflammation-resolving responses. We found evidence of local activation of B cells correlated with an age-associated B-cell signature and evidence of progressive stages of monocyte differentiation within the kidney. A clear interferon response was observed in most cells. Two chemokine receptors, CXCR4 and CX3CR1, were broadly expressed, implying a potentially central role in cell trafficking. Gene expression of immune cells in urine and kidney was highly correlated, which would suggest that urine might serve as a surrogate for kidney biopsies.

A randomized, controlled double-blind study comparing the efficacy and safety of dose-ranging voclosporin with placebo in achieving remission in patients with active lupus nephritis.

Calcineurin inhibitors added to standard-of-care induction therapy for lupus nephritis (LN) may increase complete renal remission (CRR) rates. The AURA-LV study tested the novel calcineurin inhibitor voclosporin for efficacy and safety in active LN. AURA-LV was a Phase 2, multicenter, randomized, double-blind, placebo-controlled trial of two doses of voclosporin (23.7 mg or 39.5 mg, each twice daily) versus placebo in combination with mycophenolate mofetil (2 g/d) and rapidly tapered low-dose oral corticosteroids for induction of remission in LN. The primary endpoint was CRR at 24 weeks; the secondary endpoint was CRR at 48 weeks. Two hundred sixty-five subjects from 79 centers in 20 countries were recruited and randomized to treatment for 48 weeks. CRR at week 24 was achieved by 29 (32.6%) subjects in the low-dose voclosporin group, 24 (27.3%) subjects in the high-dose voclosporin group, and 17 (19.3%) subjects in the placebo group (OR=2.03 for low-dose voclosporin versus placebo). The significantly greater CRR rate in the low-dose voclosporin group persisted at 48 weeks, and CRRs were also significantly more common in the high-dose voclosporin group compared to placebo at 48 weeks. There were more serious adverse events in both voclosporin groups, and more deaths in the low-dose group compared to placebo and high-dose voclosporin groups (11.2%, 1.1%, and 2.3%, respectively). These results suggest that the addition of low-dose voclosporin to mycophenolate mofetil and corticosteroids for induction therapy of active LN results in a superior renal response compared to mycophenolate mofetil and corticosteroids alone, but higher rates of adverse events including death were observed.

A secreted PD-L1 splice variant that covalently dimerizes and mediates immunosuppression.

Targeting immune checkpoint pathways, such as programmed death ligand-1 (PD-L1, also known as CD274 or B7-H1) or its receptor programmed cell death-1 (PD-1) has shown improved survival for patients with numerous types of cancers, not limited to lung cancer, melanoma, renal cell carcinoma, and Hodgkin lymphoma. PD-L1 is a co-inhibitory molecule whose expression on the surface of tumor cells is associated with worse prognosis in many tumors. Here we describe a splice variant (secPD-L1) that does not splice into the transmembrane domain, but instead produces a secreted form of PD-L1 that has a unique 18 amino acid tail containing a cysteine that allows it to homodimerize and more effectively inhibit lymphocyte function than monomeric soluble PD-L1. We show that recombinant secPD-L1 can dimerize and inhibit T-cell proliferation and IFN-gamma production in vitro. The secPD-L1 variant is expressed by malignant cells in vitro that also express high levels of full-length PD-L1. Transcriptomic analysis of gene expression across The Cancer Genome Atlas found the strongest association of secPD-L1 with full-length PD-L1, but also with subsets of immunologic genes, such as in myeloid-derived suppressor cells. Moreover, the splice variant is also expressed in normal tissues and within normal peripheral blood cells it is preferentially expressed in activated myeloid cells. This is the first report of a form of secreted PD-L1 that homodimerizes and is functionally active. SecPD-L1 may function as a paracrine negative immune regulator within the tumor, since secPD-L1 does not require a cell-to-cell interaction to mediate its inhibitory effect.

Inhibitory Anti-Peroxidasin Antibodies in Pulmonary-Renal Syndromes.

BACKGROUND: Goodpasture syndrome (GP) is a pulmonary-renal syndrome characterized by autoantibodies directed against the NC1 domains of collagen IV in the glomerular and alveolar basement membranes. Exposure of the cryptic epitope is thought to occur via disruption of sulfilimine crosslinks in the NC1 domain that are formed by peroxidasin-dependent production of hypobromous acid. Peroxidasin, a heme peroxidase, has significant structural overlap with myeloperoxidase (MPO), and MPO-ANCA is present both before and at GP diagnosis in some patients. We determined whether autoantibodies directed against peroxidasin are also detected in GP. METHODS: We used ELISA and competitive binding assays to assess the presence and specificity of autoantibodies in serum from patients with GP and healthy controls. Peroxidasin activity was fluorometrically measured in the presence of partially purified IgG from patients or controls. Clinical disease severity was gauged by Birmingham Vasculitis Activity Score. RESULTS: We detected anti-peroxidasin autoantibodies in the serum of patients with GP before and at clinical presentation. Enriched anti-peroxidasin antibodies inhibited peroxidasin-mediated hypobromous acid production in vitro. The anti-peroxidasin antibodies recognized peroxidasin but not soluble MPO. However, these antibodies did crossreact with MPO coated on the polystyrene plates used for ELISAs. Finally, peroxidasin-specific antibodies were also found in serum from patients with anti-MPO vasculitis and were associated with significantly more active clinical disease. CONCLUSIONS: Anti-peroxidasin antibodies, which would previously have been mischaracterized, are associated with pulmonary-renal syndromes, both before and during active disease, and may be involved in disease activity and pathogenesis in some patients.

Combination Therapy With Rituximab and Cyclophosphamide for Remission Induction in ANCA Vasculitis.

INTRODUCTION: Remission induction in antineutrophil cytoplasmic autoantibody (ANCA) vasculitis may be complicated by slow response to treatment and toxicity from glucocorticoids. We describe outcomes with a novel remission induction regimen combining rituximab with a short course of low-dose, oral cyclophosphamide and an accelerated prednisone taper. METHODS: Patients were included in this retrospective study if they had newly diagnosed or relapsing ANCA vasculitis with a Birmingham Vasculitis Activity Score for Wegener Granulomatosis (BVAS-WG) ≥3 and received a standardized remission induction regimen. The primary outcome was complete remission, defined as a BVAS-WG of 0 and a prednisone dose of ≤7.5 mg/d. RESULTS: We identified 129 patients who met the inclusion criteria, 31% of whom also received plasma exchange (PLEX) for rapidly progressive glomerulonephritis (RPGN) or diffuse alveolar hemorrhage. Seventy percent of patients had myeloperoxidase (MPO)-ANCA and 9% had relapsing disease. Median time to complete remission was 4 months (interquartile range [IQR] 3.9-4.4), and by 5 months 84% of patients were in complete remission. Prednisone was tapered to discontinuation as tolerated, such that the median prednisone dose at 8 months was 0 mg/d (IQR 0-2.5). In patients with RPGN, proteinase 3-ANCA was associated with a greater increase in eGFR at 6 months compared with MPO-ANCA (16 vs. 5.6 ml/min per 1.73m2; P = 0.028). During the year following remission, 1 major relapse occurred over 122 patient-years. Serious infections occurred more frequently in patients receiving PLEX and were associated with increasing age and diffuse alveolar hemorrhage. Four deaths occurred, 3 of which were associated with serious infections. CONCLUSION: Combination therapy was efficacious, allowed for rapid tapering of high-dose glucocorticoids and was well tolerated.

Pregnancy Outcomes in Patients with Glomerular Disease Attending a Single Academic Center in North Carolina.

BACKGROUND: Contemporary data regarding pregnancy outcomes in US patients with primary glomerular diseases are lacking. We aimed to report fetal and maternal outcomes among women with biopsy-proven primary glomerular disease who received obstetric care at a single large academic US center. METHODS: All women with a biopsy-confirmed primary glomerular disease diagnosis and without end-stage kidney disease who received obstetric care at the University of North Carolina (UNC) Hospitals (1996-2015) were identified using the Glomerular Disease Collaborative Network registry and the UNC Hospitals Perinatal Database. The primary study outcome was perinatal death (stillbirth at >20 weeks or neonatal death). Secondary outcomes included premature birth (<37 weeks), birth weight, preeclampsia, and kidney function changes (postpartum vs. baseline). Demographics, clinical characteristics, and outcomes were compared across glomerular disease subtypes. RESULTS: Among 48 pregnancies in 43 women (IgA nephropathy n = 17, focal segmental glomerulosclerosis [FSGS] n = 16, membranous nephropathy n = 6, minimal change disease n = 4), 13% of pregnancies resulted in perinatal death and 48% of babies were born prematurely. From a maternal perspective, 33% of pregnancies were complicated by preeclampsia, 39% by a doubling of urinary protein, and 27% by a ≥50% increase in serum creatinine. Outcome differences across glomerular disease subtypes were not statistically significant, although decline in kidney function appeared most frequent in FSGS. CONCLUSION: Adverse pregnancy outcomes are frequently observed in women with glomerular disease. The independent influence of glomerular disease subtype on outcomes requires further study. More widespread reporting and analysis of pregnancy outcomes in women with glomerular disease are urgently needed.

The Evolving Role of Rituximab in Adult Minimal Change Glomerulopathy.

BACKGROUND: Minimal-change glomerulopathy is defined histologically by the presence of normal glomeruli on light microscopy and diffuse podocyte effacement on electron microscopy. Although effective in children, corticosteroid treatment in adults is more variable and time to response can be prolonged. Data to support rituximab use in adults with corticosteroid-dependent or resistant minimal-change glomerulopathy are limited. Here, we describe the clinical course of adults with corticosteroid-dependent or -resistant minimal-change glomerulopathy who received rituximab. METHODS: Demographic and clinical data were collected and analyzed from all adult patients with native kidney, biopsy-proven, minimal-change glomerulopathy who were administered rituximab between 2009 and 2014 and cared for at the UNC Kidney Center. RESULTS: Ten patients with corticosteroid-resistant (n = 5) or corticosteroid-dependent (n = 5) idiopathic minimal-change glomerulopathy were treated with rituximab between 2009 and 2014. Rituximab treatment induced remission in all 10 patients with a median time to remission of 2 months. The median time from rituximab to corticosteroid discontinuation was 3.5 months. The median remission time was 29 months and follow-up time was 39.5 months. No serious adverse events attributable to rituximab were observed. CONCLUSION: Rituximab induced remission in all patients with corticosteroid-dependent or -resistant minimal-change glomerulopathy, and may hold great therapeutic potential with good efficacy and minimal toxicity. Mounting evidence implies that a well-conducted randomized controlled clinical trial using rituximab in adults with minimal-change glomerulopathy in both corticosteroid-resistant and corticosteroid-dependent patients is warranted.

Combination therapy with rituximab, low-dose cyclophosphamide, and prednisone for idiopathic membranous nephropathy: a case series.

BACKGROUND: Membranous nephropathy is a common cause of the nephrotic syndrome. Treatment with standard regimens fails to induce complete remission in most patients. We evaluated the efficacy of combination therapy with rituximab, low-dose, oral cyclophosphamide, and an accelerated prednisone taper (RCP) for the treatment of idiopathic membranous nephropathy. METHODS: We analyzed 15 consecutive patients with idiopathic membranous nephropathy treated with RCP at Massachusetts General Hospital. Seven patients (47%) received RCP as initial therapy, and the other eight patients (53%) received RCP for relapsing or refractory disease. All patients had at least 1 year of follow-up. The co-primary outcomes were attainment of partial and complete remission. Partial remission was defined as a urinary protein to creatinine ratio (UPCR) < 3 g/g and a 50% reduction from baseline. Complete remission was defined as a UPCR < 0.3 g/g. Secondary outcomes were serious adverse events and the change in proteinuria, serum creatinine, serum albumin, cholesterol, triglycerides, and immunoglobulin G levels after 1 year of treatment. RESULTS: Over a median follow-up time of 37 (IQR, 34-44) months, 100% of patients achieved partial remission and 93% of patients achieved complete remission at a median time of 2 and 13 months, respectively. After 1 year of treatment, median (IQR) UPCR declined from 8.2 (6.6-11.1) to 0.3 (0.2-0.7) g/g (P < 0.001). Three serious adverse events occurred over 51 patient years. No patients died or progressed to ESKD. CONCLUSIONS: Treatment of idiopathic membranous nephropathy with RCP resulted in high rates of complete remission. Larger studies evaluating this regimen are warranted.

Gene-Specific DNA Methylation Changes Predict Remission in Patients with ANCA-Associated Vasculitis.

ANCA-associated vasculitis is an autoimmune condition characterized by vascular inflammation and organ damage. Pharmacologically induced remission of this condition is complicated by relapses. Potential triggers of relapse are immunologic challenges and environmental insults, both of which associate with changes in epigenetic silencing modifications. Altered histone modifications implicated in gene silencing associate with aberrant autoantigen expression. To establish a link between DNA methylation, a model epigenetic gene silencing modification, and autoantigen gene expression and disease status in ANCA-associated vasculitis, we measured gene-specific DNA methylation of the autoantigen genes myeloperoxidase (MPO) and proteinase 3 (PRTN3) in leukocytes of patients with ANCA-associated vasculitis observed longitudinally (n=82) and of healthy controls (n=32). Patients with active disease demonstrated hypomethylation of MPO and PRTN3 and increased expression of the autoantigens; in remission, DNA methylation generally increased. Longitudinal analysis revealed that patients with ANCA-associated vasculitis could be divided into two groups, on the basis of whether DNA methylation increased or decreased from active disease to remission. In patients with increased DNA methylation, MPO and PRTN3 expression correlated with DNA methylation. Kaplan-Meier estimate of relapse revealed patients with increased DNA methylation at the PRTN3 promoter had a significantly greater probability of a relapse-free period (P<0.001), independent of ANCA serotype. Patients with decreased DNA methylation at the PRTN3 promoter had a greater risk of relapse (hazard ratio, 4.55; 95% confidence interval, 2.09 to 9.91). Thus, changes in the DNA methylation status of the PRTN3 promoter may predict the likelihood of stable remission and explain autoantigen gene regulation.

Effect of Continuous B Cell Depletion With Rituximab on Pathogenic Autoantibodies and Total IgG Levels in Antineutrophil Cytoplasmic Antibody-Associated Vasculitis.

OBJECTIVE: To evaluate the effect of rituximab on pathogenic autoantibodies and total Ig levels, and to identify serious adverse events in patients with antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) treated with continuous B cell depletion. METHODS: We conducted a retrospective analysis of 239 patients with AAV treated with rituximab-induced continuous B cell depletion. Two treatment cohorts were analyzed: an induction group (n = 52) and a maintenance group (n = 237). Changes in ANCA titers and total Ig levels over time were evaluated using mixed-effects models. Risk factors for serious infections during maintenance treatment were evaluated using Poisson regression. RESULTS: During induction, IgG levels fell at a mean rate of 6% per month (95% confidence interval [95% CI] 4, 8%), while ANCA levels declined at a mean rate of 47% per month (95% CI 42, 52%) and 48% per month (95% CI 42, 54%) for patients with antimyeloperoxidase (anti-MPO) antibodies and those with anti-proteinase 3 (anti-PR3) antibodies, respectively. During maintenance treatment, with a median duration of 2.4 years (interquartile range 1.5, 4.0 years), IgG levels declined a mean of 0.6% per year (95% CI -0.2, 1.4%). New significant hypogammaglobulinemia (IgG level of <400 mg/dl) during maintenance treatment occurred in 4.6% of the patients, all of whom were in the lowest baseline IgG quartile. Serious infections during maintenance therapy occurred at a rate of 0.85 per 10 patient-years (95% CI 0.66, 1.1) and were independently associated with an IgG level of <400 mg/dl. CONCLUSION: B cell-targeted therapy causes a preferential decline in ANCA titers relative to total IgG levels. Despite prolonged maintenance therapy with rituximab, IgG levels remain essentially constant. Serious infections were rare.

Histone modification signature at myeloperoxidase and proteinase 3 in patients with anti-neutrophil cytoplasmic autoantibody-associated vasculitis.

BACKGROUND: Anti-neutrophil cytoplasmic autoantibody (ANCA)-associated vasculitis (AAV) is a systemic autoimmune disease characterized by destructive vascular inflammation. Two prominent ANCA autoantigens are myeloperoxidase (MPO) and proteinase 3 (PR3), and transcription of MPO and PRTN3, the genes encoding the autoantigens, is associated with disease activity. We investigated whether patients with AAV have alterations in histone modifications, particularly those associated with transcriptional activation, at MPO and PRTN3. RESULTS: We identified a network of genes regulating histone modifications that were differentially expressed in AAV patients compared to healthy controls. We focused on four genes (EHMT1 and EHMT2, ING4, and MSL1) and found their expression correlated with expression of MPO and PRTN3. Methylation of histone H3K9, catalyzed by EHMT1 and EHMT2 and associated with gene silencing, was most depleted at MPO and PRTN3 in patients with active disease and the highest MPO and PRTN3 expression. Acetylation of histone H4K16, modified by complexes containing ING4 and MSL1 and associated with gene activation, was most enriched at MPO and PRTN3 in patients with active disease and the highest MPO and PRTN3 expression. Methylation at H3K4, a mark of transcriptional activation, was enriched at MPO and PRTN3 in patients and healthy controls. CONCLUSIONS: MPO and PRTN3 in neutrophils of AAV patients with active disease have a distinct pattern of histone modifications, which implicates epigenetic mechanisms in regulating expression of autoantigen genes and suggests that the epigenome may be involved in AAV pathogenesis.

Defining Glomerular Disease in Mechanistic Terms: Implementing an Integrative Biology Approach in Nephrology.

Advances in biomedical research allow for the capture of an unprecedented level of genetic, molecular, and clinical information from large patient cohorts, where the quest for precision medicine can be pursued. An overarching goal of precision medicine is to integrate the large-scale genetic and molecular data with deep phenotypic information to identify a new mechanistic disease classification. This classification can ideally be used to meet the clinical goal of the right medication for the right patient at the right time. Glomerular disease presents a formidable challenge for precision medicine. Patients present with similar signs and symptoms, which cross the current disease categories. The diseases are grouped by shared histopathologic features, but individual patients have dramatic variability in presentation, progression, and response to therapy, reflecting the underlying biologic heterogeneity within each glomerular disease category. Despite the clinical challenge, glomerular disease has several unique advantages to building multilayered datasets connecting genetic, molecular, and structural information needed to address the goals of precision medicine in this population. Kidney biopsy tissue, obtained during routine clinical care, provides a direct window into the molecular mechanisms active in the affected organ. In addition, urine is a biofluid ideally suited for repeated measurement from the diseased organ as a liquid biopsy with potential to reflect the dynamic state of renal tissue. In our review, current approaches for large-scale data generation and integration along the genotype-phenotype continuum in glomerular disease will be summarized. Several successful examples of this integrative biology approach within glomerular disease will be highlighted along with an outlook on how achieving a mechanistic disease classification could help to shape glomerular disease research and care in the future.

Clinical Features of Reported Ethylene Glycol Exposures in the United States.

BACKGROUND: Ethylene glycol is highly toxic and represents an important cause of poisonings worldwide. Toxicity can result in central nervous system dysfunction, cardiovascular compromise, elevated anion gap metabolic acidosis and acute kidney injury. Many states have passed laws requiring addition of the bittering agent, denatonium benzoate, to ethylene glycol solutions to reduce severity of exposures. The objectives of this study were to identify differences between unintentional and intentional exposures and to evaluate the utility of denatonium benzoate as a deterrent. METHODS AND FINDINGS: Using the National Poison Data System, we performed a retrospective analysis of reported cases of ethylene glycol exposures from January 2006 to December 2013. Outcome classification was summed for intentionality and used as a basis for comparison of effect groups. There were 45,097 cases of ethylene glycol exposures resulting in 154 deaths. Individuals more likely to experience major effects or death were older, male, and presented with more severe symptoms requiring higher levels of care. Latitude and season did not correlate with increased exposures; however, there were more exposures in rural areas. Denatonium benzoate use appeared to have no effect on exposure severity or number. CONCLUSION: Deaths due to ethylene glycol exposure were uncommon; however, there were major clinical effects and more exposures in rural areas. Addition of denatonium benzoate was not associated with a reduction in exposures. Alternative means to deter ingestion are needed. These findings suggest the need to consider replacing ethylene glycol with alternative and less toxic agents.

Recent pathogenetic advances in ANCA-associated vasculitis.

Since the discovery of anti-neutrophil cytoplasmic autoantibodies (ANCA), great strides have been made in elucidating the etiology and pathogenesis of disease. In this article, we review recent published key breakthroughs in understanding the pathogenesis of ANCA vasculitis, including some that may lead to novel therapeutics. These breakthroughs have occurred in multiple areas of investigation. A European genome-wide association study (GWAS) revealed the importance of the genetic contribution of proteinase 3 (PR3) and its endogenous inhibitor, alpha (1)-antitrypsin as well as HLA risk. Epigenetic modification of autoantigen genes appears to contribute to perpetuation of disease and possibly relapse risk. Autoantigen excision, a novel method to detect autoantibody epitopes using mass spectrometry, not only revealed pathogenic epitopes in myeloperoxidase (MPO)-ANCA vasculitis and identified unique MPO-ANCA responsible for the majority of ANCA-negative small vessel vasculitis, but has vast applicability to other autoantibody-mediated diseases. An explosion of biomarker studies has revealed circulating cytokines and alternative complement pathway products that may predict active disease. Interestingly, alternative complement pathway blockade in the murine model of disease is protective and a clinical trial in humans using an oral alternative complement pathway inhibitor is underway. Increasing clarity of the role of B and T cells in disease pathogenesis is ongoing. B cell depleting agents have shown great utility in remission induction and maintenance, and monitoring specific B cell subsets during the disease course may have predictive power for remission maintenance. Despite these substantial advances, more research is needed including, but not limited to, validation of existing discoveries. As additional novel discoveries emerge, so will novel therapies, and it is with great hope that these collective insights will ultimately lead to prevention and cure.

Comparison and evaluation of lupus nephritis response criteria in lupus activity indices and clinical trials.

Systemic lupus erythematosus (SLE) is a systemic autoimmune disease with diverse manifestations. Although the approval of new therapies includes only one agent in 50 years, a number of promising new drugs are in development. Lupus nephritis is a dreaded complication of SLE as it is associated with significant morbidity and mortality. Advancing the treatment of lupus nephritis requires well-designed clinical trials and this can be challenging in SLE. The major obstacles involve identifying the correct population of patients to enroll and ensuring that a clinically appropriate and patient-centered endpoint is being measured. In this review, we will first discuss the clinical utility of endpoints chosen to represent lupus nephritis in global disease activity scales. Second, we will review completed and active trials focused on lupus nephritis and discuss the endpoints chosen. There are many important lessons to be learned from existing assessment tools and clinical trials. Reviewing these points will help ensure that future efforts will yield meaningful disease activity measures and well-designed clinical trials to advance our understanding of lupus management.