Zinc-finger protein CXXC5 promotes breast carcinogenesis by regulating the TSC1/mTOR signaling pathway.

CXXC5, a member of the CXXC family of zinc-finger proteins, is associated with numerous pathological processes. However, the pathophysiological function of CXXC5 has not been clearly established. Herein, we found that CXXC5 interacts with the CRL4B and NuRD complexes. Screening of transcriptional targets downstream of the CXXC5-CRL4B-NuRD complex by next-generation sequencing (chromatin immunoprecipitation sequencing) revealed that the complex regulates the transcriptional repression process of a cohort of genes, including TSC1 (tuberous sclerosis complex subunit 1), which play important roles in cell growth and mammalian target of rapamycin signaling pathway regulation, and whose abnormal regulation results in the activation of programmed cell death-ligand protein 1 (PD-L1). Intriguingly, CXXC5 expression increased after stimulation with vitamin B2 but decreased after vitamin D treatment. We also found that the CXXC5-CRL4B-NuRD complex promotes the proliferation of tumor cells in vitro and accelerates the growth of breast cancer in vivo. The expression of CXXC5, CUL4B, and MTA1 increased during the occurrence and development of breast cancer, and correspondingly, TSC1 expression decreased. Meanwhile, a high expression of CXXC5 was positively correlated with the histological grade of high malignancy and poor survival of patients. In conclusion, our study revealed that CXXC5-mediated TSC1 suppression activates the mammalian target of rapamycin pathway, reduces autophagic cell death, induces PD-L1-mediated immune suppression, and results in tumor development, shedding light on the mechanism of the pathophysiological function of CXXC5.

Short-chain fatty acids ameliorate experimental anti-glomerular basement membrane disease.

BACKGROUND: Short-chain fatty acids (SCFAs), as the link between gut microbiota and the immune system, had been reported to be protective in many autoimmune diseases by the modulation of T cell differentiation. The pathogenic role of autoreactive Th1 and Th17 cells and the protective role of Treg cells in the pathogenesis of anti-GBM disease have been fully demonstrated. Thus, the present study aimed to investigate the therapeutic effects of SCFAs in a rat model of anti-GBM disease. MATERIALS AND METHODS: Experimental anti-GBM disease was constructed by immunizing Wistar Kyoto rats with a nephrogenic T cell epitope α3127-148, and intervened by sodium acetate, sodium propionate, or sodium butyrate, 150 mM in the drinking water from day 0 to 42. Kidney injury was accessed by the biochemical analyzer, immunofluorescence, and immunohistochemistry. Antibody response was detected by ELISA. T cell clustering and proliferation were detected by flow cytometry. Human kidney 2 (HK2) cells were stimulated in vitro and cytokines were assessed by quantitative real-time PCR. RESULTS: Treatment with sodium acetate, sodium propionate, or sodium butyrate ameliorated the severity of kidney impairment in rats with anti-GBM glomerulonephritis. In the sodium butyrate-treated rats, the urinary protein, serum creatinine, and blood urea nitrogen levels were significantly lower; the percentage of crescent formation in glomeruli was significantly reduced; and the kidneys showed reduced IgG deposition, complement activation, T cell, and macrophage infiltration as well as the level of circulating antibodies against anti-α3(IV)NC1. The treatment of sodium butyrate reduced the α3127-148-specific T cell activation and increased the Treg cells differentiation and the intestinal beneficial bacteria flora. It also alleviated the damage of HK2 cells treated with inflammatory factors and complement. CONCLUSION: Treatment with SCFAs, especially butyrate, alleviated anti-GBM nephritis in rat model, indicating its potential therapeutic effects in clinical usage.

Differential contributions of the C5b-9 and C5a/C5aR pathways to microvascular and macrovascular thrombosis in complement-mediated thrombotic microangiopathy patients.

To clarify the role of the C5a/C5aR (C5a receptor) and C5b-9 pathways in macrovascular thrombosis (MAT) and renal microthrombosis (MIT), 73 renal biopsy-proven complement-mediated thrombotic microangiopathy (C-TMA) patients were enrolled; 9 patients with pure MAT and 13 patients with pure MIT were selected for further study. Twenty-five external C-TMA patients were selected as the validation cohort. Plasma C5a and sC5b-9 (soluble C5b-9) levels were significantly higher in patients with MAT than in those with MIT (P = 0.008, P = 0.041, respectively). The mean optical density of C5aR1 in the kidney was significantly higher in MAT patients than in those with MIT (P < 0.001). Both urinary sC5b-9 levels (MIT: P < 0.001, MAT: P = 0.004) and renal deposition of C5b-9 (MIT: P < 0.001, MAT: P = 0.001) were significantly higher in C-TMA patients compared to normal control, but were similar between MAT and MIT groups. In the correlation analysis within 22C-TMA patients, urinary sC5b-9 levels and renal deposition of C5b-9 were positively correlated to renal MIT formation (P = 0.009 and P = 0.031, respectively). Furthermore, the renal citrullinated histone H3 (CitH3)- and neutrophil elastase (NE)-positive area ratios were both significantly higher in the MAT group than in the MIT group (P = 0.006 and P = 0.020, respectively). Therefore, the local C5b-9 and C5a/C5aR1 pathways might have differential contributions to MIT and MAT formation in the disease.

Genome-wide analysis of wheat xyloglucan endotransglucosylase/hydrolase (XTH) gene family revealed TaXTH17 involved in abiotic stress responses.

BACKGROUND: Environmental stresses, including high salinity and drought, severely diminish wheat yield and quality globally. The xyloglucan endotransglucosylase/hydrolase (XTH) family represents a class of cell wall-modifying enzymes and plays important roles in plants growth, development and stress adaptation. However, systematic analyses of XTH family genes and their functions under salt and drought stresses have not been undertaken in wheat. RESULTS: In this study, we identified a total of 135 XTH genes in wheat, which were clustered into three evolutionary groups. These TaXTHs were unevenly distributed on 21 chromosomes of wheat with a majority of TaXTHs located on homelogous groups 2, 3 and 7. Gene duplication analysis revealed that segmental and tandem duplication were the main reasons for the expansion of XTH family in wheat. Interaction network predictions indicated that TaXTHs could interact with multiple proteins, including three kinases, one methyltransferase and one gibberellin-regulated protein. The promoters of the TaXTH genes harbored various cis-acting elements related to stress and hormone responses. RNA-seq data analyses showed that some TaXTH genes were induced by salt and drought stresses. Furthermore, we verified that TaXTH17 was induced by abiotic stresses and phytohormone treatments, and demonstrated that TaXTH17 was localized in the secretory pathway and cell wall. Functional analyses conducted in heterologous expression systems and in wheat established that TaXTH17 plays a negative role in plant resistance to salt and drought. CONCLUSIONS: We identified 135 XTH genes in wheat and conducted comprehensive analyses of their phylogenetic relationships, gene structures, conserved motifs, gene duplication events, chromosome locations, interaction networks, cis-acting elements and gene expression patterns. Furthermore, we provided solid evidence supporting the notion that TaXTH17 plays a negative role in plant resistance to salt and drought stresses. Collectively, our results provide valuable insights into understanding wheat XTHs, particularly their involvement in plant stress responses, and establish a foundation for further functional and mechanistic studies of TaXTHs.

OsAlR3 regulates aluminum tolerance through promoting the secretion of organic acids and the expression of antioxidant genes in rice.

In acidic soils, aluminum (Al) toxicity inhibits the growth and development of plant roots and affects nutrient and water absorption, leading to reduced yield and quality. Therefore, it is crucial to investigate and identify candidate genes for Al tolerance and elucidate their physiological and molecular mechanisms under Al stress. In this study, we identified a new gene OsAlR3 regulating Al tolerance, and analyzed its mechanism from physiological, transcriptional and metabolic levels. Compared with the WT, malondialdehyde (MDA) and hydrogen peroxide (H2O2) content were significantly increased, superoxide dismutase (SOD) activity and citric acid (CA) content were significantly decreased in the osalr3 mutant lines when exposed to Al stress. Under Al stress, the osalr3 exhibited decreased expression of antioxidant-related genes and lower organic acid content compared with WT. Integrated transcriptome and metabolome analysis showed the phenylpropanoid biosynthetic pathway plays an important role in OsAlR3-mediated Al tolerance. Exogenous CA and oxalic acid (OA) could increase total root length and enhance the antioxidant capacity in the mutant lines under Al stress. Conclusively, we found a new gene OsAlR3 that positively regulates Al tolerance by promoting the chelation of Al ions through the secretion of organic acids, and increasing the expression of antioxidant genes.

FTY720 ameliorates experimental MPO-ANCA-associated vasculitis by regulating fatty acid oxidation via the neutrophil PPARα-CPT1a pathway.

OBJECTIVES: Increasing studies demonstrated the importance of C5a and anti-neutrophil cytoplasmic antibody (ANCA)-induced neutrophil activation in the pathogenesis of ANCA-associated vasculitis (AAV). Sphingosine-1-phosphate (S1P) acts as a downstream effector molecule of C5a and enhances neutrophil activation induced by C5a and ANCA. The current study investigated the role of a S1P receptor modulator FTY720 in experimental autoimmune vasculitis (EAV) and explored the immunometabolism-related mechanisms of FTY720 in modulating ANCA-induced neutrophil activation. METHODS: The effects of FTY720 in EAV were evaluated by quantifying hematuria, proteinuria, crescent formation, tubulointerstitial injury and pulmonary hemorrhage. RNA sequencing of renal cortex and gene enrichment analysis were performed. The proteins of key identified pathways were analyzed in neutrophils isolated from peripheral blood of patients with active AAV and normal controls. We assessed the effects of FTY720 on ANCA-induced neutrophil respiratory burst and neutrophil extracellular traps formation (NETosis). RESULTS: FTY720 treatment significantly attenuated renal injury and pulmonary hemorrhage in EAV. RNA sequencing analyses of renal cortex demonstrated enhanced fatty acid oxidation (FAO) and peroxisome proliferators-activated receptors (PPAR) signalling in FTY720-treated rats. Compared with normal controls, patients with active AAV showed decreased FAO in neutrophils. FTY720-treated differentiated HL-60 cells showed increased expression of carnitine palmitoyltransferase 1A (CPT1a) and PPARα. Blocking or knockdown of CPT1a or PPARα in isolated human neutrophils and HL-60 cells reversed the inhibitory effects of FTY720 on ANCA-induced neutrophil respiratory burst and NETosis. CONCLUSION: FTY720 attenuated renal injury in EAV through upregulating FAO via the PPARα-CPT1a pathway in neutrophils, offering potential immunometabolic targets in AAV treatment.

Natural variation in OsSEC13 HOMOLOG 1 modulates redox homeostasis to confer cold tolerance in rice.

Rice (Oryza sativa L.) is a cold-sensitive species that often faces cold stress, which adversely affects yield productivity and quality. However, the genetic basis for low-temperature adaptation in rice remains unclear. Here, we demonstrate that 2 functional polymorphisms in O. sativa SEC13 Homolog 1 (OsSEH1), encoding a WD40-repeat nucleoporin, between the 2 subspecies O. sativa japonica and O. sativa indica rice, may have facilitated cold adaptation in japonica rice. We show that OsSEH1 of the japonica variety expressed in OsSEH1MSD plants (transgenic line overexpressing the OsSEH1 allele from Mangshuidao [MSD], cold-tolerant landrace) has a higher affinity for O. sativa metallothionein 2b (OsMT2b) than that of OsSEH1 of indica. This high affinity of OsSEH1MSD for OsMT2b results in inhibition of OsMT2b degradation, with decreased accumulation of reactive oxygen species and increased cold tolerance. Transcriptome analysis indicates that OsSEH1 positively regulates the expression of the genes encoding dehydration-responsive element-binding transcription factors, i.e. OsDREB1 genes, and induces the expression of multiple cold-regulated genes to enhance cold tolerance. Our findings highlight a breeding resource for improving cold tolerance in rice.

The effect of preeclampsia on long-term kidney function among pregnant women with chronic kidney disease.

BACKGROUND AND HYPOTHESIS: The association between superimposed preeclampsia and an elevated risk of long-term kidney function decline or end-stage kidney disease (ESKD) in patients with chronic kidney disease (CKD) has not been determined. This study aimed to analyze the association between preeclampsia and kidney function deterioration in CKD patients. METHODS: This was a retrospective cohort study that included the clinical information of 103 pregnant CKD patients with preeclampsia and 103 matched CKD patients without preeclampsia who were followed-up for a minimum of 1 year after their first pregnancy from January 1, 2009, to May 31, 2022. Robust Cox regression analysis was also conducted to evaluate the effects of preeclampsia on long-term kidney function decline or ESKD in CKD patients. K-M curves were used to compare renal survival within different subgroups via the log-rank test. RESULTS: During the follow-up period, 44 (42.72%) CKD patients with preeclampsia and 20 (19.42%) without preeclampsia had an estimated glomerular filtration rate (eGFR) decrease >30% or developed ESKD. Compared with CKD patients without preeclampsia, the eGFR decreased more significantly in patients with preeclampsia [98.43 (79.48, 116.47) to 81.32 (41.20, 102.97) mL/min/1.73 m2 vs. 99.43 (79.00, 118.50) to 89.44 (63.69, 105.30) mL/min/1.73 m2; P=0.034]. The rate of eGFR decrease was more pronounced in patients with preeclampsia (17.38% vs. 10.05%, p<0.05). Multivariate analysis revealed that early-onset preeclampsia (preeclampsia that developed before 34 weeks of gestation) (HR=2.61, 95% CI=1.32-5.16, P=0.006) and late-onset preeclampsia (HR=2.54, 95% CI=1.34-4.83, P=0.004) were both risk factors for an eGFR decrease >30% or ESKD. CONCLUSION: Preeclampsia was associated with a greater risk of long-term kidney function decline or ESKD among CKD patients, especially in patients with early-onset preeclampsia.

Differences Between Cystatin C- and Creatinine-Based Estimated Glomerular Filtration Rate and Association with Mortality and Cardiovascular Events: Results from Three Cohorts of Adults with Diabetes.

BACKGROUND AND HYPOTHESIS: To explore the association between the differences between cystatin C- and creatinine-based estimated glomerular filtration rate (eGFRdiff) with the risk of mortality and cardiovascular (CV) events in individuals with diabetes. METHODS: Three prospective cohorts analyzed data of adults with diabetes from the Incident, Development, and Prognosis of Diabetic Kidney Disease (INDEED) study (2016-2017 to 2020) in China, the National Health, Nutrition Examination Survey (NHANES, 1999-2004 to 2019) in the United States, and UK Biobank (UKB, 2006-2010 to 2022). Baseline eGFRdiff was calculated using both absolute difference between cystatin C- and creatinine-based calculations (eGFRabdiff), and the ratio between them (eGFRrediff). Cox proportional hazards regression models were used to investigate the association between eGFRdiff and outcomes including all-cause mortality and incident CV events. RESULTS: A total of 8,129 individuals from the INDEED (aged 60.7±10.0 years), 1,634 from the NHANES (aged 62.5±14.4 years), and 29,358 from the UKB (aged 59.4±7.3 years;) were included. At baseline, 43.6%, 32.4% and 42.1% of participants in the INDEED, NHANES and UKB had an eGFRabdiff value ≥15 ml/min/1.73 m2. During a median follow-up of 3.8 years for the INDEED, 15.2 years for the NHANES, and 13.5 years for the UKB, a total of 430, 936 and 6143 deaths and a total of 481, 183 and 5583 CV events occurred, respectively. Each 1-standard deviation higher baseline eGFRabdiff was independently associated with a lower risk of all-cause mortality and CV events, with hazard ratios (HRs) of 0.77 and 0.82 in the INDEED, 0.70 and 0.68 in the NHANES, and 0.66 and 0.78 in the UKB. Similar results were observed for eGFRrediff. CONCLUSIONS: eGFRdiff represents a marker of adverse events for diabetes among general population. Monitoring both eGFRcys and eGFRcr yields additional prognostic information and has clinical utility in identifying high-risk individuals for mortality and CV events.

Surgical procedure and recurrence of upper urinary tract stone: a national-wide study based on hospitalized patients.

PURPOSE: This study aimed to investigate the influence of surgical intervention on recurrence risk of upper urinary tract stone and compare the medical burden of various surgical procedures. METHODS: This study analyzed data from patients with upper urinary tract stone extracted from a national database of hospitalized patients in China, from January 2013 to December 2018. Surgical recurrence was defined as patients experience surgical procedures for upper urinary tract stone again with a time interval over 90 days. Associations of surgical procedures with surgical recurrence were evaluated by Cox regression. RESULTS: In total, 556,217 patients with upper urinary tract stone were included in the present analysis. The mean age of the population was 49.9 ± 13.1 years and 64.1% were men. During a median follow-up of 2.7 years (IQR 1.5-4.0 years), 23,012 patients (4.1%) had surgical recurrence with an incidence rate of 14.9 per 1000 person-years. Compared to patients receiving open surgery, ESWL (HR, 1.59; 95% CI 1.49-1.70), URS (HR, 1.38; 95% CI 1.31-1.45), and PCNL (HR, 1.11; 95% CI 1.06-1.18) showed a greater risk for surgical recurrence. Patients receiving ESWL had the shortest hospital stay length and the lowest cost among the 4 procedures. CONCLUSIONS: Compared with open surgery, ESWL, URS, and PCNL are associated with higher risks of surgical recurrence for upper urinary tract stone, while ESWL showed the least medical burden including both expenditure and hospital stay length. How to keep balance of intervention efficacy and medical expenditure is an important issue to be weighed cautiously in clinic practice and studied more in the future.

Macrocarpal B blocks the binding between the phospholipase A2 receptor and its antibodies.

The pathogenic role of anti-phospholipase A2 receptor (PLA2R) antibodies in primary membranous nephropathy (MN) has been well-established. This study aimed to identify potential small-molecule inhibitors against the PLA2R-antibody interaction, offering potential therapeutic benefits. A comprehensive screening of over 4000 small-molecule compounds was conducted by ELISA to assess their inhibitory effects on the binding between the immobilized full-length extracellular PLA2R and its antibodies. The affinity of anti-PLA2R IgG from MN patients and the inhibitory efficacy of each compound were evaluated via surface plasmon resonance (SPR). Human podocyte injuries were analyzed using CCK-8 assay, wound healing assay, western blot analysis, and immunofluorescence, after exposure to MN plasma +/- blocking compound. Fifteen compounds were identified as potential inhibitors, demonstrating inhibition rates >20 % for the PLA2R-antibody interaction. Anti-PLA2R IgG exhibited a consistent affinity among patients (KD = 10-8 M). Macrocarpal B emerged as the most potent inhibitor, reducing the antigen-antibody interaction by nearly 30 % in a dose-dependent manner, comparable to the performance of the 31-mer peptide from the CysR domain. Macrocarpal B bound to the immobilized PLA2R with an affinity of 1.47 × 10-6 M, while showing no binding to anti-PLA2R IgG. Human podocytes exposed to MN plasma showed decreased podocin expression, impaired migration function, and reduced cell viability. Macrocarpal B inhibited the binding of anti-PLA2R IgG to podocytes and reduced the cellular injuries.

Light-chain proximal tubulopathy: a retrospective study from a single Chinese nephrology referral center.

Background: Light-chain proximal tubulopathy (LCPT) is a rare disease characterized by the accumulation of monoclonal light chains within proximal tubular cells. This study aimed to investigate the clinical characteristics of LCPT from a single Chinese nephrology referral center.Methods: Patients with kidney biopsy-proven isolated LCPT between 2016 and 2022 at Peking University First Hospital were retrospectively included. Clinical data, kidney pathological type, treatment, and prognosis were analyzed.Results: Nineteen patients were enrolled, the mean age at diagnosis was 57 ± 11 and the sex ratio was 6/13 (female/male). Mean proteinuria was 2.44 ± 1.89 g/24 hr and the mean estimated glomerular filtration rate (eGFR) at the point of biopsy was 59.640 ± 27.449 ml/min/1.73 m2. κ-restriction (84%) was dominant among LCPTs. An abnormal free light chain ratio was observed in 86% of the patients. Proximal tubulopathy with cytoplasmic inclusions accounted for the majority (53%), followed by tubulopathy associated with interstitial inflammation reaction (26%), proximal tubulopathy without cytoplasmic inclusions (16%), and proximal tubulopathy with lysosomal indigestion/constipation (5%). One patient presented with acute kidney injury and 16 patients presented with chronic kidney disease. Regarding follow-up, patients received bortezomib-based or R-CHOP chemotherapy or supportive treatment only. The mean follow-up time was 22 ± 16 months, and the mean eGFR was 63.098 ± 27.439 ml/min/1.73 m2 at the end of follow-up. These patients showed improved or stable kidney function.Conclusions: This is the first case series report of LCPT in four different pathological types in northern China. Clone-targeted chemotherapy may help preserve the kidney function in these patients.

Clinicopathological characteristics and gene mutations in 11 patients with lipoprotein glomerulopathy.

OBJECTIVE: Lipoprotein glomerulopathy (LPG) is a rare disorder characterized by the development of glomerular lipoprotein thrombosis. LPG exhibits familial aggregation, with mutations in the apolipoprotein E (APOE) gene identified as the leading cause of this disease. This study aimed to investigate APOE gene mutations and the clinicopathological features in eleven LPG patients. METHODS: Clinicopathological and follow-up data were obtained by extracting DNA, followed by APOE coding region sequencing analysis. This study analyzed clinical and pathological manifestations, gene mutations, treatment and prognosis. RESULTS: The mean age of the eleven patients was 33.82 years. Among them, five had a positive family history for LPG, ten presented with proteinuria, four exhibited nephrotic syndrome, and six presented with microscopic hematuria. Dyslipidemia was identified in ten patients. In all renal specimens, there was evident dilation of glomerular capillary lumens containing lipoprotein thrombi, and positive oil red O staining was observed in frozen sections of all samples. APOE gene testing revealed that one patient had no mutations, while the remaining ten patients exhibited mutations in the APOE gene, with three patients presenting with multiple mutations simultaneously. Following the confirmation of LPG diagnosis, treatment with angiotensin-converting enzyme inhibitor (ACEI)/angiotensin receptor blocker (ARB) was initiated, and the disease progressed slowly. CONCLUSION: LPG is histologically characterized by lamellated lipoprotein thrombi in glomeruli, and kidney biopsy is essential for diagnosis. Mutations in the APOE gene are the leading cause of LPG. This study revealed clinicopathological characteristics and APOE gene mutations in patients with LPG, which helps us better understand the disease.

Dual-Planar Monopole Antenna-Based Remote Sensing System for Microwave Medical Applications.

Neurodegenerative diseases (NDs) can be life threatening and have chronic impacts on patients and society. Timely diagnosis and treatment are imperative to prevent deterioration. Conventional imaging modalities, such as Computed Tomography (CT), Magnetic Resonance Imaging (MRI), and Positron Emission Tomography (PET), are expensive and not readily accessible to patients. Microwave sensing and imaging (MSI) systems are promising tools for monitoring pathological changes, namely the lateral ventricle enlargement associated with ND, in a non-invasive and convenient way. This paper presents a dual-planar monopole antenna-based remote sensing system for ND monitoring. First, planar monopole antennas were designed using the simulation software CST Studio Suite. The antenna analysis was carried out regarding the reflection coefficient, gain, radiation pattern, time domain characterization, E-field distribution, and Specific Absorption Rate (SAR). The designed antennas were then integrated with a controlling circuit as a remote sensing system. The system was experimentally validated on brain phantoms using a vector network analyzer and a laptop. The collected reflection coefficient data were processed using a radar-based imaging algorithm to reconstruct images indicating brain abnormality in ND. The results suggest that the system could serve as a low-cost and efficient tool for long-term monitoring of ND, particularly in clinics and care home scenarios.

A Chinese Multi-Specialty Delphi Consensus to Optimize RAASi Usage and Hyperkalaemia Management in Patients with Chronic Kidney Disease and Heart Failure.

Objective Variations are present in common clinical practices regarding best practice in managing hyperkalaemia (HK), there is therefore a need to establish a multi-specialty approach to optimal renin-angiotension-aldosterone system inhibitors (RAASi) usage and HK management in patients with chronic kidney disease (CKD) & heart failure (HF).This study aimed to establish a multi-speciality approach to the optimal use of RAASi and the management of HK in patients with CKD and HF. Methods A steering expert group of cardiology and nephrology experts across China were convened to discuss challenges to HK management through a nominal group technique. The group then created a list of 41 statements for a consensus questionnaire, which was distributed for a further survey in extended panel group of cardiologists and nephrologists across China. Consensus was assessed using a modified Delphi technique, with agreement defined as "strong" (≥75% and <90%) and "very strong" (≥90%). The steering group, data collection, and analysis were aided by an independent facilitator. Results A total of 150 responses from 21 provinces across China were recruited in the survey. Respondents were comprised of an even split (n=75, 50%) between cardiologists and nephrologists. All 41 statements achieved the 75% consensus agreement threshold, of which 27 statements attained very strong consensus (≥90% agreement) and 14 attained strong consensus (agreement between 75% and 90%). Conclusion Based on the agreement levels from respondents, the steering group agreed a set of recommendations intended to improve patient outcomes in the use of RAASi therapy and HK management in China.

Autoantibodies against laminin-521 are pathogenic in anti-glomerular basement membrane disease.

Anti-glomerular basement membrane (anti-GBM) disease is an organ-specific autoimmune disorder characterized by autoantibodies against GBM components. Evidence from human inherited kidney diseases and animal models suggests that the α, ß, and γ chains of laminin-521 are all essential for maintaining the glomerular filtration barrier. We previously demonstrated that laminin-521 is a novel autoantigen within the GBM and that autoantibodies to laminin-521 are present in about one-third of patients. In the present study, we investigated the pathogenicity of autoantibodies against laminin-521 with clinical and animal studies. Herein, a rare case of anti-GBM disease was reported with circulating autoantibodies binding to laminin-521 but not to the NC1 domains of α1-α5(IV) collagen. Immunoblot identified circulating IgG from this patient bound laminin α5 and γ1 chains. A decrease in antibody levels was associated with improved clinical presentation after plasmapheresis and immunosuppressive treatments. Furthermore, immunization with laminin-521 in female Wistar-Kyoto rats induced crescentic glomerulonephritis with linear IgG deposits along the GBM, complement activation along with infiltration of T cells and macrophages. Lung hemorrhage occurred in 75.0% of the rats and was identified by the presence of erythrocyte infiltrates and hemosiderin-laden macrophages in the lung tissue. Sera and kidney-eluted antibodies from rats immunized with laminin-521 demonstrated specific IgG binding to laminin-521 but not to human α3(IV)NC1, while the opposite was observed in human α3(IV)NC1-immunized rats. Thus, our patient data and animal studies imply a possible independent pathogenic role of autoantibodies against laminin-521 in the development of anti-GBM disease.

Mapping the T cell epitopes of the M-type transmembrane phospholipase A2 receptor in primary membranous nephropathy.

The M-type phospholipase A2 receptor (PLA2R) is the major autoantigen of primary membranous nephropathy (MN). Despite many studies on B-cell epitopes recognized by antibodies, little is known about T-cell epitopes. Herein, we synthesized 123 linear peptides, each consisting of 15-22 amino acids with 8-12 amino acid overlaps, across ten domains of PLA2R. Their binding capacity to risk (DRB1∗1501, DRB1∗0301) and protective (DRB1∗0901, DRB1∗0701) HLA molecules was then assessed by flow cytometry. Proliferation of CD4+ T cells from patients with anti-PLA2R positive MN was analyzed after peptide stimulation. Cytokines produced by activated peripheral blood mononuclear cells were measured by cytometric bead arrays. We identified 17 PLA2R peptides that bound to both DRB1∗1501 and DRB1∗0301 molecules with high capacity. Some of these peptides showed decreased binding to heterozygous DRB1∗1501/0901 and DRB1∗0301/0701. Ten of the 17 peptides (CysR1, CysR10, CysR12, FnII-3, CTLD3-9, CTLD3-10, CTLD3-11, CTLD5-2-1, CTLD7-1 and CTLD7-2) induced significant proliferation of CD4+ T cells from patients with MN than cells from healthy individuals. Upon activation by these peptides, peripheral blood mononuclear cells from patients with MN produced higher levels of pro-inflammatory cytokines, predominantly IL-6, TNF-α, IL-10, IL-9 and IL-17. Thus, we mapped and identified ten peptides in the CysR, FnII, CTLD3, CTLD5, and CTLD7 domains of PLA2R as potential T-cell epitopes of MN. These findings are a first step towards developing peptide-specific immunotherapies.

Molecular architecture of proliferative lupus nephritis as elucidated using 50-plex imaging mass cytometry proteomics.

Due to unique advantages that allow high-dimensional tissue profiling, we postulated imaging mass cytometry (IMC) may shed novel insights on the molecular makeup of proliferative lupus nephritis (LN). This study interrogates the spatial expression profiles of 50 target proteins in LN and control kidneys. Proliferative LN glomeruli are marked by podocyte loss with immune infiltration dominated by CD45RO+, HLA-DR+ memory CD4 and CD8 T-cells, and CD163+ macrophages, with similar changes in tubulointerstitial regions. Macrophages are the predominant HLA-DR expressing antigen presenting cells with little expression elsewhere, while macrophages and T-cells predominate cellular crescents. End-stage sclerotic glomeruli are encircled by an acellular fibro-epithelial Bowman's space surrounded by immune infiltrates, all enmeshed in fibronectin. Proliferative LN also shows signs indicative of epithelial to mesenchymal plasticity of tubular cells and parietal epithelial cells. IMC enabled proteomics is a powerful tool to delineate the spatial architecture of LN at the protein level.

A modified renal risk score for Chinese patients with antineutrophil cytoplasmic antibody-associated vasculitis.

BACKGROUND: The renal risk score (RRS) is a useful tool to predict end-stage renal disease (ESRD) in patients with antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV). The current study aimed to validate the predictive performance of RRS and to further modify this model in Chinese AAV patients. METHODS: Two hundred and seventy-two patients diagnosed with AAV confirmed by renal biopsies were retrospectively enrolled from a single center. The RRS was calculated based on 3 categorical variables, i.e., the proportion of normal glomeruli, the proportion of interstitial fibrosis and tubular atrophy (IF/TA), and eGFR at biopsy, classifying these patients into low-, medium-, and high-risk groups. In addition, a modified model was developed based on the RRS and was further validated in another independent cohort of 117 AAV patients. The predictive performance of each model was evaluated according to discrimination and calibration. RESULTS: Patients were classified by the RRS into low- (26.5%), medium- (46.7%), and high-risk (26.8%) groups, with 120-month renal survival rates of 93.3%, 57.2%, and 18.4%, respectively (P < 0.001). The RRS showed good discrimination but less satisfactory calibration. Therefore, a modified model with improved discrimination and calibration was developed in Chinese AAV patients, with eGFR, proportion of normal glomeruli (both as continuous variables), and IF/TA (< 25%, 25-50%, > 50%) included. Internal and external validation of the modified model were performed. Finally, an online risk prediction tool was developed based on the modified model. CONCLUSIONS: The RRS was an independent predictor of ESRD of AAV patients. The modified model could predict the probability of ESRD for AAV patients with improved performance in Chinese AAV patients.

Autoimmunity in Anti-Glomerular Basement Membrane Disease: A Review of Mechanisms and Prospects for Immunotherapy.

Anti-glomerular basement membrane (anti-GBM) disease is an organ-specific autoimmune disorder characterized by autoantibodies against the glomerular and alveolar basement membranes, leading to rapidly progressive glomerulonephritis and severe alveolar hemorrhage. The noncollagenous domain of the α3 chain of type IV collagen, α3(IV)NC1, contains the main target autoantigen in this disease. Epitope mapping studies of α3(IV)NC1 have identified several nephritogenic epitopes and critical residues that bind to autoantibodies and trigger anti-GBM disease. The discovery of novel target antigens has revealed the heterogeneous nature of this disease. In addition, both epitope spreading and mimicry have been implicated in the pathogenesis of anti-GBM disease. Epitope spreading refers to the development of autoimmunity to new autoepitopes, thus worsening disease progression, whereas epitope mimicry, which occurs via sharing of critical residues with microbial peptides, can initiate autoimmunity. An understanding of these autoimmune responses may open opportunities to explore potential new therapeutic approaches for this disease. We review how current advances in epitope mapping, identification of novel autoantigens, and the phenomena of epitope spreading and mimicry have heightened the understanding of autoimmunity in the pathogenesis of anti-GBM disease, and we discuss prospects for immunotherapy.