LN Patients Research Articles

Mesenchymal stem cell transplantation as a potential therapy for refractory lupus nephritis: A systematic review

AbstractBackgroundLupus nephritis (LN) results in high morbidity and mortality in patients with systemic lupus erythematosus. Refractory cases of standard immunosuppressive therapy have been recorded. Mesenchymal stem cell transplantation (MSCT) shows potential use in autoimmune diseases. We aim to review MSCT in the treatment of refractory LN.MethodsPublished articles were systematically extracted from the databases in May 2022. The quality of the studies was assessed using the Oxford Centre for Evidence‐Based Medicine critical appraisal checklist.ResultsFour studies were included. All studies recruit severe or refractory LN patients and show significant improvement in post‐MSCT 24‐h proteinuria. However, the improvement of renal function after MSCT is inconsistent between studies after a 1‐month follow‐up, with one study showing deterioration of the estimated glomerular filtration rate after 3 months and one study showing an increase in serum creatinine at 6 and 9 months. Moreover, all studies show improvement in Systemic Lupus Erythematosus Disease Activity Index scores after MSCT, while two studies show that a decrease in anti‐double‐stranded DNA (anti‐dsDNA) levels after MSCT is only evident for up to 1‐month period.ConclusionsMSCT can be effective, especially in severe or refractory LN. More randomized‐controlled trials are needed to support this evidence.

Renal interferon-inducible protein 16 expression is associated with disease activity and prognosis in lupus nephritis

BackgroundLupus nephritis (LN) is one of the most severe complications of systemic lupus erythematosus (SLE). However, the current management of LN remains unsatisfactory due to sneaky symptoms during early stages and lack of reliable predictors of disease progression.MethodsBioinformatics and machine learning algorithms were initially used to explore the potential biomarkers for LN development. Identified biomarker expression was evaluated by immunohistochemistry (IHC) and multiplex immunofluorescence (IF) in 104 LN patients, 12 diabetic kidney disease (DKD) patients, 12 minimal change disease (MCD) patients, 12 IgA nephropathy (IgAN) patients and 14 normal controls (NC). The association of biomarker expression with clinicopathologic indices and prognosis was analyzed. Gene Set Enrichment Analysis (GSEA) and Gene Set Variation Analysis (GSVA) were utilized to explore potential mechanisms.ResultsInterferon-inducible protein 16 (IFI16) was identified as a potential biomarker for LN. IFI16 was highly expressed in the kidneys of LN patients compared to those with MCD, DKD, IgAN or NC. IFI16 co-localized with certain renal and inflammatory cells. Glomerular IFI16 expression was correlated with pathological activity indices of LN, while tubulointerstitial IFI16 expression was correlated with pathological chronicity indices. Renal IFI16 expression was positively associated with systemic lupus erythematosus disease activity index (SLEDAI) and serum creatinine while negatively related to baseline eGFR and serum complement C3. Additionally, higher IFI16 expression was closely related to poorer prognosis of LN patients. GSEA and GSVA suggested that IFI16 expression was involved in adaptive immune-related processes of LN.ConclusionRenal IFI16 expression is a potential biomarker for disease activity and clinical prognosis in LN patients. Renal IFI16 levels may be used to shed light on predicting the renal response and develop precise therapy for LN.

#5689 ASSOCIATION BETWEEN INTERLEUKIN-37 RS3811047 POLYMORPHISM AND LUPUS NEPHRITIS IN AN EGYPTIAN POPULATION

Abstract Background and Aims Systemic lupus erythematosus (SLE) is a chronic, clinically heterogenous, autoimmune disorder with unpredictable course and features ranging from mild skin affection to life-threatening involvement of major organs. Interleukin 37 (IL-37) is a cytokine with anti-inflammatory and immune-suppressive effects; it suppresses both innate and adaptive immune responses, thus protecting against excessive inflammation-induced tissue damage. Aim investigate the association of IL-37 (rs3811047) polymorphism with lupus nephritis in Egyptian population. Method This case-control study comprised 3 groups: 109 SLE patients without nephritis, 97 SLE patients with LN, and 240 healthy controls. History taking, clinical examination, disease activity in SLE patients was assessed and routine laboratory tests were done. Genotyping of the IL-37 rs3811047 polymorphism was done using real time polymerase chain reaction (PCR). Results The AA genotype was more frequently represented in LN patients (21.6%) compared to SLE patients without LN (7.3%) (p = 0.007), and carriers of the AA genotype had four times increased susceptibility to acquire LN compared to GG and GA genotype carriers (OR: 4.1). Likewise, the A allele was more represented in LN patients (43%) than in SLE patients without LN (30%) (p = 0.004), and the carriers of the A allele had nearly two times more risk of developing LN compared to carriers of the G allele (OR: 1.79). Moreover, the AA genotype was associated with LN susceptibility under the recessive genetic model (OR = 3.49, CI: 1.47-8.30) (p = 0.002), but not under other genetic models. Conclusion The AA genotype of the IL-37 rs3811047 polymorphism contributes to the development of SLE in Egyptian patients with doubled risk of acquiring LN in carriers of the allele A.

#4210 ZETOMIPZOMIB DEMONSTRATES CLINICALLY MEANINGFUL IMPROVEMENT IN UPCR IN NEPHROTIC RANGE PROTEINURIA PATIENTS: RESULTS FROM THE OPEN-LABEL MISSION STUDY

Abstract Background and Aims Prospective cohorts have shown that patients with LN and nephrotic range proteinuria at baseline have a lower probability of achieving renal response [1]. These patients may require more time due to slower proteinuria recovery. Results previously reported on the Phase 2, open-label MISSION study evaluating the safety and tolerability of zetomipzomib in active proliferative LN including patients with nephrotic range proteinuria, demonstrated clinically meaningful renal responses [2]. A post-hoc analysis of MISSION patients with nephrotic range proteinuria is presented here. Method In the MISSON Phase 2 study, patients with active proliferative LN (Class III or IV ± V) with 24-hour urine protein to creatinine ratios (UPCR) ≥1.0 mg/mg despite stable background therapy received 60 mg of zetomipzomib subcutaneously once weekly (first dose: 30 mg) in addition to stable background therapy for 24 weeks. End of treatment (EOT) was at Week (W) 25, and end of study (EOS) occurred at W37. The primary endpoint was the number of patients with ≥50% reduction in UPCR from baseline after 24 weeks of treatment. Nephrotic range proteinuria was defined as UPCR ≥3.0 mg/mg at baseline as per KDIGO 2021 Clinical Practice Guideline for the Management of Glomerular Diseases. Results Of 17 evaluable patients who reached EOT, 4 patients had nephrotic range proteinuria, with 3 having hypoalbuminemia (serum albumin ≤3.5 g/dL) at baseline. Patients with nephrotic range proteinuria had mean LN duration of 4.14 years with mean 24-hour UPCR of 5.78 mg/mg, mean serum albumin of 3.0 g/dL, mean blood pressure of 124/81 mmHg and mean eGFR of 122.5 mL/min/1.73 m2. All 4 patients were on concomitant corticosteroids (mean dose: 19.81 mg/d), mycophenolate mofetil, hydroxychloroquine and antihypertensives. After 24 weeks of zetomipzomib treatment, 3/4 patients with nephrotic range proteinuria achieved ≥50% reduction in UPCR at W25 (EOT) and W37 (EOS, 12 weeks post-treatment) (Table 1). Serum albumin levels also improved and normalized by EOS in all 3 patients with hypoalbuminemia at baseline (Table 1). eGFR levels generally remained stable throughout the study. Reduction of daily steroid dose to 10 mg/day was observed in all 4 patients as early as W13 and at EOT/EOS while other background therapy doses remained stable throughout the study. Improvement and/or normalization in key serologic biomarkers, including anti-dsDNA and C3/C4, were also observed in patients with abnormal levels at baseline. Conclusion In this post-hoc subgroup analysis of MISSION Phase 2 study, zetomipzomib treatment demonstrated clinically meaningful improvement in UPCR and normalization of albumin levels in patients with nephrotic range proteinuria and hypoalbuminemia. These results further support the potential activity of zetomipzomib in hard-to-treat LN patients.

#4570 RELATION OF KIDNEY BIOPSY FINDINGS TO CLINICAL OUTCOMES IN PATIENTS WITH LUPUS NEPHRITIS TREATED WITH AN ANTAGONISTIC ANTI-CD40 ANTIBODY (BI 655064)

Abstract Background and Aims Lupus nephritis (LN) is the most serious complication of systemic lupus erythematosus with a high risk of end-stage kidney disease and a high need of better treatment. A recent randomized, double-blind, placebo-controlled, phase II trial tested doses of 120, 180 and 240 mg of the anti-CD40 monoclonal antibody BI 655064 as add-on to standard of care (MMF + glucocorticoids), in patients with active LN (proteinuria > 1 g/day) for 52 weeks. Although the trial did not demonstrate a dose-response relationship for the primary endpoint determined by complete renal response, a potential efficacy benefit of BI 655064 180 mg and 240 mg was found in a post-hoc analysis. We investigated whether a treatment effect was related to findings in the pre-treatment renal biopsy. Method Biopsies from 101 patients with LN class III or IV, confirmed in a central review conducted according to a previously established protocol, were included. Protein/creatinine ratio (UPCR, based on spot urine) and eGFR were determined at every visit. For each, the last available UPCR and the last available eGFR values, linear regressions (based on the respective baselines) of all patients irrespective of therapy were calculated, and subjects were classified according to their individual performance, “Better” or “Worse” than the average. The modified activity and chronicity indices as well as all biopsy parameters, which are not already contained in the indices, were compared for differences between the “Better” and “Worse”. Parameters with p< 0.1 in the univariate analyses were entered into a multivariate logistic regression model, and a routine model selection procedure (with p< 0.2) was used to identify parameters predictive for clinical outcome. As monocytes express CD40, which is the target of BI 655064, a further question was whether high dose treatment with BI 655064 (180/240 mg) was beneficial when monocytes were present in the biopsy, using a model which adjusted for all predictors identified in the multivariate model. Results The results of the univariate and the multivariate analysis of biopsy parameters are shown in Table 1. Improvement in UPCR was better if the modified chronicity index was low. In addition, LN class IV subjects had a marginally better prognosis than class III. The effect of high-dose treatment with BI 655064 was better when monocytes were present. eGFR outcome was better if the modified chronicity index was low and, conversely, the modified activity index was high. Further, the presence of synechia/adhesions was a negative predictor for positive outcome. There was no indication for an effect of high-dose treatment with 655064 on eGFR when monocytes were present. Conclusion This post-hoc analysis of the BI 655064 trial used a novel approach which investigated whether specific histological lesions in renal biopsies were related to treatment outcome. Although the number of patients was limited, our results suggest that treatment with higher dose anti-CD40 may improve the reduction of proteinuria when monocytes are present in the biopsy. This indicates that specific information from renal biopsies could ultimately improve the choice of treatment for individual LN patients.

#3858 ASSESSING THE EFFECTIVENESS OF LONG-TERM BELIMUMAB THERAPY IN LUPUS NEPHRITIS: A SINGLE-CENTRE OBSERVATIONAL STUDY

Abstract Background and Aims Lupus nephritis (LN) is a major cause of morbidity and mortality in systemic lupus erythematosus (SLE). Belimumab, a monoclonal antibody that inhibits B-cell activating factor, has demonstrated efficacy in decreasing proteinuria, prevention of flares and achieving renal response after two years. However, data on its long-term efficacy is limited. The aim of this observational study is to assess the efficacy of belimumab in biopsy-proven LN patients over the medium and long term. Method In this retrospective observational study at our centre, patients with documented history of biopsy-proven LN who received belimumab were selected for analysis. Data on renal function, proteinuria (24 hours) and haematuria were collected. Immunologic activity (Anti-double-stranded-DNA, C3 and C4) was assessed. Data were retrieved at three moments: belimumab initiation, 12 months after the start of therapy and when treatment was discontinued. When treatment had not been discontinued, last available data was used. Renal flares were identified. The observational period was adjusted to be consistent between pre- and post-belimumab treatments. Clinically relevant outcomes such as possible adverse effects or major pathologic events were actively searched in patient records. Finally, the initiation of any additional antiproteinuric treatment was reported. Data analysis was performed using IBM SPSS Statistics 21®. When sample distributions were found to be normal, a parametric T-test was performed. An analysis of outcomes for patients receiving belimumab for more than 24 months was also performed. Results Seventeen patients diagnosed of LN between 1991 and 2021 began belimumab from 2014 to 2022, ten of whom received belimumab for more than 24 months. Mean treatment duration was 41,8 months. Patient characteristics are presented in Table 1, while analytic results are summarized in Table 2. A statistically significant decrease in proteinuria stands out 12 months after starting treatment with belimumab and a decrease in anti-dsDNA antibodies. As regards the subgroup of extended follow-up, results did not differ in hypothesis contrast tests. Overall, 17 renal flares were identified prior to belimumab initiation, while 9 flares were identified following its initiation (Fisher's Exact Test: P = 0,092). A patient was diagnosed with acute bacterial meningitis, although the relationship to the drug is unclear since the patient was also receiving other immunosuppressive medications. This event did not lead to drug withdrawal. Only one patient started an angiotensin converting enzyme inhibitor (ACEI), immediately after initiating belimumab. Conclusion Currently, the optimal treatment duration with belimumab in LN is not known. Despite a decline in median GFR, results from this cohort of patients suggest a tendency to controlling proteinuria, haematuria and immunologic activity, over the middle and long term. A remarkable yet not significant decline in renal flares was observed. Finally, no relevant changes in immunosuppressive or antiproteinuric medication were made, allowing to avoid biases for this reason.

#3564 DIAGNOSTIC AND PROGNOSTIC SIGNIFICANCE OF INTERLEUKIN-6 IN LUPUS NEPHRITIS

Abstract Background and Aims Lupus nephritis is a frequent and potentially serious complication of SLE. The present study is aimed to evaluate the usefulness of urinary IL-6 as a non-invasive diagnostic & prognostic biomarkers of disease activity in LN. Method The study was done in IMS and Sum hospital, Bhubaneswar, India from January, 2018 to July 2022. The study included 20 healthy controls and 32 patients of SLE diagnosed based of Systemic Lupus International Collaborating Clinic (SLICC) criteria, who presented with renal involvement. The exclusion criteria was inability to obtain informed consent and SLE patients without renal involvement. Urinary IL-6 levels were assessed in patients before initiation of therapy and in controls by quantitative sandwich EASIA technique using human IL-6 EASIA kit (DIA Source Belgium). All patients underwent ultrasound guided renal biopsy and the results were classified according to the ISN/RPS classification of LN. Treatment was started in all patients according to class of LN as per KDIGO guidelines. Urinary IL-6 levels were again assessed in all patients after 6 months of induction phase treatment. Results In our 32 patients, female to male ratio was 7:1 with a mean age of 28.68 ± 9.28 years. In our study, ANA was positive in 96.8%, anti-dsDNA Ab in 78%, C3 was low in 78% & C4 was low in 72% of LN patients. Based on renal biopsy findings, there were 2 cases of Class II LN, 6 cases of Class III LN, 19 cases of Class IV LN and 5 cases of Class V LN. In our study, patients with LN have significantly higher urinary IL-6 levels (301.58 ± 483.96 pg/ml) as compared to 20 healthy controls (4.7±2.282 pg/ml) with a p-value = 0.001. The mean urinary IL-6 levels in different ISN/RPS classes of LN patients based on renal biopsy showed a statistically significant difference between different classes (p-value = 0.005). Highest values of urinary IL-6 (475.126 ± 580.90 pg/ml) was seen in Class-IV LN which is most active form of LN and lowest values (28.28 ±7.30pg/ml) were seen in Class-II LN. In our study, a significant correlation was found between serum creatinine & presence of active urinary sediment with urinary IL-6 levels but there was no correlation between 24 hour urinary protein with urinary IL-6 levels in patients of LN (p value = 0.799). In our study 2 patients (6.25%) died, 3 patients (9.37%) lost follow up, 16 patients (50%) achieved complete remission, 8 patients (25%) achieved partial remission and 3 patients (9.37%) did not show any improvement after 6 months treatment. Urinary IL-6 levels were near normal among 12 patients (75%) out of 16 patients who achieved remission after 6 months of induction treatment (p-value = 0.001). Urinary IL-6 levels remained elevated in all 8 patients (100%) who achieved partial remission (p-value = 0.028, and also remained elevated in all 3 patients who had no remission at all (p-value = 0.109). Conclusion Urinary IL-6 may provide a simple non-invasive potential biomarker of disease activity of renal involvement in patients with SLE and may be used to monitor therapy.

Microbiological Investigations of Fine Needle Aspirates from Newly Suspected and Previously Treated Tubercular Lymphadenitis Patients.

Extrapulmonary tuberculosis (EPTB), particularly tubercular lymphadenitis (TBLN), remains to pose a huge public health problem in Ethiopia. A significant number of TBLN patients who completed a full course anti-TB treatment regimen were reported to have enlarged lymph nodes and other TB-like clinical presentations. This could either be from a paradoxical reaction or microbiological relapse, possibly due to mono/multi-drug resistance. To investigate the rate of mono and multidrug resistance patterns of Mycobacterium tuberculosis as a cause of the observed treatment failures in clinically diagnosed and anti-TB treatment (newly or previously)-initiated LN patients. A cross-sectional study was conducted on 126 TBLN-suspected and previously treated patients between March and September 2022. Data were analyzed using SPSS (Version 26.0). Descriptive statistics were used to determine the frequency, percentage, sensitivity, specificity, and positive and negative predictive values. The level of agreement was determined using Cohen's kappa and a Chi-square test was used to measure the association between risk factors and laboratory test outcomes. A P-value <0.05 was considered statistically significant. Mycobacterium tuberculosis was confirmed in 28.6% (N=36) of the 126 cases using BACTEC MGIT 960 culture detection method. Approximately, 13% (N=16) of the samples were collected from previously treated TBLN patients, of which 5/16 (31.3%) were multi-drug resistant, 7/16 were drug-sensitive and 4/16 were culture negative. To rule out other non-tuberculous agents, all samples were grown on blood and Mycosel agar plates, and no growth was detected. The emergence of drug resistant (DR) TB seems to not just be limited to pulmonary form but also to TBLN. In this study we observed a considerable number of microbiologically confirmed relapses among previously treated cases, possibly indicating the need for confirmation of drug resistance using rapid molecular methods or phenotypical methods during treatment follow up.

The Value of Lipocalin-2 in Patients with Systemic Lupus Erythematosus.

Systemic lupus erythematosus (SLE) is a chronic autoimmune multisystem disease predominantly affecting women in the childbearing period. The majority of the pathology in SLE is related to deposits of immune complexes in various organs, which trigger complement and other mediators of inflammation. SLE is characterized by a very large spectrum of clinical manifestations accompanied by prototypic abnormalities of the immune system. Methods: This study was conducted on thirty SLE patients who were diagnosed according to the American College of Rheumatology (ACR) revised criteria. The patient was selected from the outpatient clinic of Rheumatology and Rehabilitation of Ain Shams University Hospital. Fifteen subjects, matched for age and sex, were included in the study and served as a control group. Comparison of quantitative variables between the study groups was done using the Kruskal Wallis analysis of variance (ANOVA) test with Mann Whitney U test for independent samples as posthoc multiple 2-group comparisons. A probability value (p-value) less than 0.05 was considered statistically significant. All statistical calculations were done using computer programs Microsoft Excel 2007 (Microsoft Corporation, NY, USA) and SPSS (Statistical Package for the Social Science; SPSS Inc., Chicago, IL, USA) version 15 for Microsoft Windows. Results and Discussion: Our results come in agreement with the study done by Farzaneh and his colleagues in 2013, who studied fifty-two lupus patients; urinary lipocalin-2 levels in LN patients were significantly higher than those in non-LN patients. Also, our results were in accordance with the study done by Hammad, who studied 33 children with active SLE (22 with and 11 without LN) and compared them with 15 matched controls. Levels of urinary NGAL were higher in patients with LN than those without LN. These findings come in consistent with previous work done by Youssef and his co-worker in 2015, who studied 44 SLE patients and divided them into two groups, group I (twenty-two patients with LN) and group II (twenty-two patients without LN), the urinary lipocalin-2 had the highest mean levels in LN patients (group I) compared to group II and controls with a statistically significant difference. Also, between SLE patients without nephritis (group II) and controls. Conclusions: In this study, urinary lipocalin-2 was significantly higher in the SLE patients compared to the control group, and the lupus nephritis patients, when compared to the patients with SLE without nephritis,showed significantly higher levels of urinary lipocalin-2. The significant association of the urinary lipocalin-2 with the renal SLEDAI shows that urinary lipocalin-2 can be an early biomarker to diagnose patients with lupus nephritis and to detect renal disease activity.

Global-feature of autoimmune glomerulonephritis using proteomic analysis of laser capture microdissected glomeruli.

IgA nephropathy (IgAN), (LN), membranous nephropathy (MN), and minimal change nephropathy (MCN) are all belonged to autoimmune glomerulonephritis. This study aimed to identify the specific proteomic characteristics of the four GNs diseases in order to provide frameworks for developing the appropriate drug for patients diagnosed with GNs disease. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) was utilized to investigate proteomic features of glomerular tissues obtained by laser capture microdissection (LCM). 8 normal control cases, 11 IgAN cases, 19 LN cases, 5 MN cases, and 3 MCN cases in this study were selected for bioinformatics analyses. The shared overlapping proteins among the top 100 DEPs of each GNs type were mostly downregulated, in which only FLII was significantly downregulated in the four GNs diseases. A2M was significantly upregulated in MN, IgAN, and LN subgroups. The pathway of complement and coagulation cascades was notably activated with NES value ranging 2.77 to 3.39 among MCN, MN, IgAN, and LN diseases, but the pattern of protein expression level were significantly different. In LN patients, the increased activity of complement and coagulation cascades was contributed by the high expression of multiple complements (C1QB, C3, C4A, C4B, C6, C8B, C8G, C9). Meanwhile, both C1QC and C4B were remarkably upregulated in MN patients. On the contrary, complement-regulating proteins (CD59) was substantially decreased in MCN and IgAN subgroup. The integrative proteomics analysis of the four GNs diseases provide insights into unique characteristics of GNs diseases and further serve as frameworks for precision medicine diagnosis and provide novel targets for drug development.

Prevalence and clinical significance of ANCA positivity in lupus nephritis: a case series of 116 patients and literature review.

Among our LN patients we retrospectively selected those who underwent ANCA testing the day of thekidney biopsy and before the start of induction treatment. Clinical/histopathological features at kidney biopsy and renal outcome of ANCA-positive patients were compared with those of ANCA-negative subjects. We included 116 Caucasian LN patients in the study; 16 patients [13.8%] were ANCA-positive. At kidney biopsy, ANCA-positive patients presented more frequently with an acute nephritic syndrome than ANCA-negative ones; the difference howeverdoes not reach statistical significance [44 vs. 25%, p = 0.13]. At histological evaluation, proliferative classes [100% vs 73%; p = 0.02], class IV [68.8% vs 33%; p < 0.01] and necrotizing tuft lesions [27 vs 7%, p = 0.04] were more frequent, and the activity index was higher [10 vs 7; p = 0.03] in ANCA-positive than in ANCA-negative patients. Despite worse histological features, after a 10-year observation period, there were no significant differences in the number of patients with chronic kidney function impairment (defined as eGFR<60mL/minper 1.73m2) between the ANCA-positive and negative groups [24.2 vs 26.6%, p = 0.9]. This could be the result of the more aggressive therapy, with rituximab plus cyclophosphamide, that ANCA-positive patients received more frequently than ANCA-negative ones [25 vs. 1.3%, p < 0.01]. ANCA-positive LN patients frequently have histological markers of severe activity (proliferative classes and high activity index) that require timely diagnosis and aggressive therapy to limit the development of irreversible chronic kidney damage.

Urinary exosome tsRNAs as novel markers for diagnosis and prediction of lupus nephritis.

Lupus nephritis (LN) is one of the most severe organ manifestations of systemic lupus erythematosus (SLE). Early identification of renal disease in SLE is important. Renal biopsy is currently recognized as the gold standard for diagnosing LN, however, it is invasive and inconvenient for dynamic monitoring. Urine has been considered more promising and valuable than blood in identifying inflamed kidney tissue. Here, we determine whether the signatures of tRNA-derived small noncoding RNA (tsRNA) in urinary exosomes can serve as novel biomarkers for the diagnosis of LN. tsRNA sequencing was performed in exosome extracted from pooled urine of 20 LN patients and 20 SLE without LN, and the top 10 upregulated tsRNAs were screened as candidate markers of LN. The candidate urinary exosomal tsRNAs were primarily elected by TaqMan probe-based quantitative reverse transcription-PCR (RT-PCR) in 40 samples (20 LN and 20 SLE without LN) in the training phase. In the validation phase, selected tsRNAs from the training phase were further confirmed in a larger cohort (54 LN patients and 39 SLE without LN). Receiver operating characteristic curve (ROC) analysis was conducted to evaluate the diagnostic efficacy. Upregulated levels of tRF3-Ile-AAT-1 and tiRNA5-Lys-CTT-1 in the urinary exosomes were observed in LN compared with SLE without LN (P < 0.0001 and P < 0.001) and healthy controls (P < 0.01 and P < 0.01), with the area under the curve (AUC) of 0.777 (95% CI: 0.681-0.874, sensitivity 79.63%, specificity 66.69%) and 0.715 (95% CI: 0.610-0.820, sensitivity 66.96%, specificity 76.92%) for discriminating LN from SLE without LN patients. SLE patients with mild activity and moderate to severe activity had higher levels of urinary exosome derived tRF3-Ile AAT-1 (P = 0.035 and P < 0.001) and tiRNA5-Lys-CTT-1 (P = 0.021 and P < 0.001) compared with patients with no activity. Moreover, bioinformatics analysis revealed that both of the tsRNAs regulate the immune process by modulating metabolism and signal pathway. In this study, we demonstrated that urinary exosome tsRNAs can be served as noninvasive biomarkers for the efficient diagnosis and prediction of nephritis in SLE.

Urinary markers differentially associate with kidney inflammatory activity and chronicity measures in patients with lupus nephritis

ObjectiveLupus nephritis (LN) is diagnosed by biopsy, but longitudinal monitoring assessment methods are needed. Here, in this preliminary and hypothesis-generating study, we evaluate the potential for using urine proteomics as...

HSPB5 suppresses renal inflammation and protects lupus-prone NZB/W F1 mice from severe renal damage

BackgroundLupus nephritis (LN) is an inflammatory disease of the kidneys affecting patients with systemic lupus erythematosus. Current immunosuppressive and cytotoxic therapies are associated with serious side effects and fail to protect 20–40% of LN patients from end-stage renal disease. In this study, we investigated whether a small heat shock protein, HSPB5, can reduce kidney inflammation and the clinical manifestations of the disease in NZB/W F1 mice. Furthermore, we investigated whether HSPB5 can enhance the effects of methylprednisolone, a standard-of-care drug in LN, in an endotoxemia mouse model.MethodsNZB/W F1 mice were treated with HSPB5, methylprednisolone, or vehicle from 23 to 38 weeks of age. Disease progression was evaluated by weekly proteinuria scores. At the end of the study, the blood, urine, spleens, and kidneys were collected for the assessment of proteinuria, blood urea nitrogen, kidney histology, serum IL-6 and anti-dsDNA levels, immune cell populations, and their phenotypes, as well as the transcript levels of proinflammatory chemokine/cytokines in the kidneys. HSPB5 was also evaluated in combination with methylprednisolone in a lipopolysaccharide-induced endotoxemia mouse model; serum IL-6 levels were measured at 24 h post-endotoxemia induction.ResultsHSPB5 significantly reduced terminal proteinuria and BUN and substantially improved kidney pathology. Similar trends, although to a lower extent, were observed with methylprednisolone treatment. Serum IL-6 levels and kidney expression of BAFF, IL-6, IFNγ, MCP-1 (CCL2), and KIM-1 were reduced, whereas nephrin expression was significantly preserved compared to vehicle-treated mice. Lastly, splenic Tregs and Bregs were significantly induced with HSPB5 treatment. HSPB5 in combination with methylprednisolone also significantly reduced serum IL-6 levels in endotoxemia mice.ConclusionsHSPB5 treatment reduces kidney inflammation and injury, providing therapeutic benefits in NZB/W F1 mice. Given that HSPB5 enhances the anti-inflammatory effects of methylprednisolone, there is a strong interest to develop HSBP5 as a therapeutic for the treatment of LN.

Artificial neural network - an effective tool for predicting the lupus nephritis outcome

BackgroundLupus nephropathy (LN) occurs in approximately 50% of patients with systemic lupus erythematosus (SLE), and 20% of them will eventually progress into end-stage renal disease (ESRD). A clinical tool predicting remission of proteinuria might be of utmost importance. In our work, we focused on predicting the chance of complete remission achievement in LN patients, using artificial intelligence models, especially an artificial neural network, called the multi-layer perceptron.MethodsIt was a single centre retrospective study, including 58 individuals, with diagnosed systemic lupus erythematous and biopsy proven lupus nephritis. Patients were assigned into the study cohort, between 1st January 2010 and 31st December 2020, and eventually randomly allocated either to the training set (N = 46) or testing set (N = 12). The end point was remission achievement. We have selected an array of variables, subsequently reduced to the optimal minimum set, providing the best performance.ResultsWe have obtained satisfactory results creating predictive models allowing to assess, with accuracy of 91.67%, a chance of achieving a complete remission, with a high discriminant ability (AUROC 0.9375).ConclusionOur solution allows an accurate assessment of complete remission achievement and monitoring of patients from the group with a lower probability of complete remission. The obtained models are scalable and can be improved by introducing new patient records.

Opsonization of Early Apoptotic Cells by IgG from Lupus Nephritis Amplifies Activation of Early Complement Components and Promotes Inflammatory Phagocytosis

Introduction: SSARo 60 has been reported to be exposed on the surface of early apoptotic cells and recognized by auto antibodies from lupus. The aim of this study was to explore the subsequent effects of the binding of IgG from anti-SSA positive LN patients on the fate of early apoptotic cells.

Genome-wide association study of SNP- and gene-based approaches to identify susceptibility candidates for lupus nephritis in the Han Chinese population.

BackgroundLupus nephritis (LN) is one of the most common and serious complications of systemic lupus erythaematosus (SLE). Genetic factors play important roles in the pathogenesis of LN and could be used to predict who might develop LN. The purpose of this study was to screen for susceptible candidates of LN across the whole genome in the Han Chinese population.Methods592 LN patients and 453 SLE patients without renal damage were genotyped at 492,970 single nucleotide polymorphisms (SNPs) in the genome-wide association study (GWAS). Fifty-six SNPs were selected for replication in an independent cohort of 188 LN and 171 SLE without LN patients. Further quantitative real-time (qRT) PCR was carried out in 6 LN patients and 6 healthy controls. Gene-based analysis was conducted using the versatile gene-based test for GWAS. Subsequently, enrichment and pathway analyses were performed in the DAVID database.ResultsThe GWAS analysis and the following replication research identified 9 SNPs showing suggestive correlation with LN (P<10-4). The most significant SNP was rs12606116 (18p11.32), at P=8.72×10−6. The qRT-PCR results verified the mRNA levels of LINC00470 and ADCYAP1, the closest genes to rs12606116, were significantly lower in LN patients. From the gene-based analysis, 690 genes had suggestive evidence of association (P<0.05), including LINC00470. The enrichment analysis identified the involvement of transforming growth factor beta (TGF-β) signalings in the development of LN. Lower plasma level of TGF-β1 (P<0.05) in LN patients and lower expression of transforming growth factor beta receptor 2 in lupus mice kidney (P<0.05) futher indicate the involvement of TGF-β in LN.ConclusionsOur analyses identified several promising susceptibility candidates involved in LN, and further verification of these candidates was necessary.

SLE stratification based on BAFF and IFN-I bioactivity for biologics and implications of BAFF produced by glomeruli in lupus nephritis.

B-cell activating factor (BAFF) is implicated in SLE pathogenesis. Blocking BAFF signalling has contributed to reducing glucocorticoid dosage and preventing organ damage. However, clinical characteristics of patients who may benefit from this therapy are not yet fully elucidated. Therefore, we identified patients with high BAFF-bioactivity to investigate their clinical characteristics and BAFF-producing cells. We established the reporter cell for BAFF and investigated the clinical characteristics of SLE patients with high BAFF-bioactivity. We identified BAFF-expressing kidney cells using publicly available scRNA-seq data and immunohistological analysis. SLE patients were stratified based on the bioactivity of BAFF and type-I IFN (IFN-I) to identify associated characteristic clinical manifestations. SLE patients, especially patients with LN, had significantly higher serum BAFF-bioactivity than healthy controls (HC) and non-LN patients. Additionally, single-cell-RNA-seq data and immunohistological analysis of kidney samples from LN patients revealed that BAFF is expressed in glomerular macrophages and mesangial cells. Notably, BAFF bioactivity was elevated in the urine of LN patients compared with that of non-LN patients, while no IFN-I bioactivity was detected in the urine. Furthermore, SLE stratification based on bioactivities of serum BAFF and IFN-I revealed the clinical characteristics of patients: high BAFF represented patients with LN and high IFN-I represented patients with blood and skin manifestations. Monitoring urinary BAFF-bioactivity may be valuable in diagnosing LN. Furthermore, stratification based on serum BAFF and IFN-I bioactivities may allow the identification of appropriate patients for biologics targeting BAFF and IFN-I.

Metabolic profiling reveals new serum signatures to discriminate lupus nephritis from systemic lupus erythematosus.

BackgroundLupus nephritis (LN) occurs in 50% of patients with systemic lupus erythematosus (SLE), causing considerable morbidity and even mortality. Previous studies had shown the potential of metabolic profiling in the diagnosis of SLE or LN. However, few metabonomics studies have attempted to distinguish SLE from LN based on metabolic changes. The current study was designed to find new candidate serum signatures that could differentiate LN from SLE patients using a non-targeted metabonomics method based on ultra high performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS).MethodMetabolic profiling of sera obtained from 21 healthy controls, 52 SLE patients and 43 LN patients. We used SPSS 25.0 for statistical analysis. Principal component analysis (PCA), partial least squares discriminant analysis (PLS-DA) and metabolic pathway analysis were used to analyze the metabolic data.ResultsUpon comparison of SLE and LN groups, 28 differential metabolites were detected, the majority of which were lipids and amino acids. Glycerolphospholipid metabolism, pentose and glucuronate interconversions and porphyrin and chlorophyll metabolism were obviously enriched in LN patients versus those with SLE. Among the 28 characteristic metabolites, five key serum metabolites including SM d34:2, DG (18:3(9Z,12Z,15Z)/20:5(5Z,8Z,11Z,14Z,17Z)/0:0), nervonic acid, Cer-NS d27:4, and PC (18:3(6Z,9Z,12Z)/18:3(6Z,9Z,12Z) performed higher diagnostic performance in discriminating LN from SLE (all AUC > 0.75). Moreover, combined analysis of neuritic acid, C1q, and CysC (AUC = 0.916) produced the best combined diagnosis.ConclusionThis study identified five serum metabolites that are potential indicators for the differential diagnosis of SLE and LN. Glycerolphospholipid metabolism may play an important role in the development of SLE to LN. The metabolites we screened can provide more references for the diagnosis of LN and more support for the pathophysiological study of SLE progressed to LN.

Systematic identification of key extracellular proteins as the potential biomarkers in lupus nephritis.

BackgroundLupus nephritis (LN) is the most common and severe clinical manifestation of systemic lupus erythematosus (SLE) with considerable morbidity/mortality and limited treatment options. Since kidney biopsy is a relative hysteretic indicator, it is indispensable to investigate potential biomarkers for early diagnosis and predicting clinical outcomes of LN patients. Extracellular proteins may become the promising biomarkers by the secretion into body fluid. Our study linked extracellular proteins with lupus nephritis to identify the emerging biomarkers.MethodsThe expression profiling data were acquired from the Gene Expression Omnibus (GEO) database. Meanwhile, the two gene lists encoding extracellular proteins were collected from the Human Protein Atlas (HPA) and UniProt database. Subsequently, the extracellular protein-differentially expressed genes (EP-DEGs) were screened out, and the key EP-DEGs were determined by MCODE, MCC, and Degree methods via the protein–protein interaction (PPI) network. The expression level, immune characteristics, and diagnostic value of these candidate biomarkers were investigated. Finally, the Nephroseq V5 tool was applied to evaluate the clinical significance of the key EP-DEGs.ResultsA total of 164 DEGs were acquired by comparing LN samples with healthy controls based on GSE32591 datasets. Then, 38 EP-DEGs were screened out through the intersection between DEGs and extracellular protein gene lists. Function enrichment analysis indicated that these EP-DEGs might participate in immune response and constitute the extracellular matrix. Four key EP-DEGs (LUM, TGFBI, COL1A2, and POSTN) were eventually identified as candidate biomarkers, and they were all overexpressed in LN samples. Except that LUM expression was negatively correlated with most of the immune regulatory genes, there was a positive correlation between the remaining three biomarkers and the immune regulatory genes. In addition, these biomarkers had high diagnostic value, especially the AUC value of the LUM–TGFBI combination which reached almost 1 (AUC = 0.973), demonstrating high accuracy in distinguishing LN from controls. Finally, we found a meaningful correlation of these biomarkers with sex, WHO class, and renal function such as glomerular filtration rate (GFR), serum creatinine level, and proteinuria.ConclusionIn summary, our study comprehensively identified four key EP-DEGs exerting a vital role in LN diagnosis and pathogenesis and serving as promising therapeutic targets.