Search

Extrachromosomal circular DNA (eccDNA) derived from linear chromosomes, are showed typical nucleosomal ladder pattern in agarose gel which as a known feature of apoptosis and demonstrated to be immunogenicity. In systemic lupus erythematosus (SLE) patients, elevated levels of cell-free DNA (cfDNA) can be found in either linear forms or circular forms, while circular ones are much less common and harder to detect. The molecular characteristics and function of circular forms in plasma SLE patients remains elusive. Herein, we characterized the hallmarks of plasma eccDNA in SLE patients, including the lower normalized number and GC content of eccDNA in SLE plasma than in the healthy, and SLE eccDNA number positively correlated with C3 and negatively with anti-dsDNA antibodies. The differential eccGenes (eccDNAs carrying the protein coding gene sequence) of SLE was significantly enriched in apoptosis-related pathways. The artificially synthesized eccDNA with sequences of the PRF1 exon region could promote transcriptional expression of PRF1, IFNA and IFIT3 and inhibit early-stage apoptosis. Plasma eccDNA can serve as a novel autoantigen in the pathogenesis of SLE., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Background: This dynamic nomogram model was developed to predict the probability of fetal loss in pregnant patients with systemic lupus erythematosus (SLE) with mild disease severity before conception., Methods: An analysis was conducted on 314 pregnancy records of patients with SLE who were hospitalized between January 2015 and January 2022 at Shenzhen People's Hospital, and the Longhua Branch of Shenzhen People's Hospital. Data from the Longhua Branch of the Shenzhen People's Hospital were utilized as an independent external validation cohort. The nomogram, a widely used statistical visualization tool to predict disease onset, progression, prognosis, and survival, was created after feature selection using multivariate logistic regression analysis. To evaluate the model prediction performance, we employed the receiver operating characteristic curve, calibration curve, and decision curve analysis., Results: Lupus nephritis, complement 3, immunoglobulin G, serum albumin, C-reactive protein, and hydroxychloroquine were all included in the nomogram model. The model demonstrated good calibration and discriminatory power, with an area under the curve of 0.867 (95% confidence interval: 0.787-0.947). According to decision curve analysis, the nomogram model exhibited clinical importance when the probability of fetal loss in patients with SLE ranged between 10 and 70%. The predictive ability of the model was demonstrated through external validation., Conclusion: The predictive nomogram approach may facilitate precise management of pregnant patients with SLE with mild disease severity before conception., (© 2024. The Author(s).)

Autoantibodies produced by B cells play a pivotal role in the pathogenesis of systemic lupus erythematosus (SLE). However, both the cellular source of antiphospholipid antibodies and their contributions to the development of lupus nephritis (LN) remain largely unclear. Here, we report a pathogenic role of anti-phosphatidylserine (PS) autoantibodies in the development of LN. Elevated serum PS-specific IgG levels were measured in model mice and SLE patients, especially in those with LN. PS-specific IgG accumulation was found in the kidney biopsies of LN patients. Both transfer of SLE PS-specific IgG and PS immunization triggered lupus-like glomerular immune complex deposition in recipient mice. ELISPOT analysis identified B1a cells as the main cell type that secretes PS-specific IgG in both lupus model mice and patients. Adoptive transfer of PS-specific B1a cells accelerated the PS-specific autoimmune response and renal damage in recipient lupus model mice, whereas depletion of B1a cells attenuated lupus progression. In culture, PS-specific B1a cells were significantly expanded upon treatment with chromatin components, while blockade of TLR signal cascades by DNase I digestion and inhibitory ODN 2088 or R406 treatment profoundly abrogated chromatin-induced PS-specific IgG secretion by lupus B1a cells. Thus, our study has demonstrated that the anti-PS autoantibodies produced by B1 cells contribute to lupus nephritis development. Our findings that blockade of the TLR/Syk signaling cascade inhibits PS-specific B1-cell expansion provide new insights into lupus pathogenesis and may facilitate the development of novel therapeutic targets for the treatment of LN in SLE., (© 2023. The Author(s), under exclusive licence to CSI and USTC.)

Systemic lupus erythematosus (SLE) is an autoimmune disease affecting thousands of people. There are still no effective biomarkers for SLE diagnosis and disease activity assessment. We performed proteomics and metabolomics analyses of serum from 121 SLE patients and 106 healthy individuals, and identified 90 proteins and 76 metabolites significantly changed. Several apolipoproteins and the metabolite arachidonic acid were significantly associated with disease activity. Apolipoprotein A-IV (APOA4), LysoPC(16:0), punicic acid and stearidonic acid were correlated with renal function. Random forest model using the significantly changed molecules identified 3 proteins including ATRN, THBS1 and SERPINC1, and 5 metabolites including cholesterol, palmitoleoylethanolamide, octadecanamide, palmitamide and linoleoylethanolamide, as potential biomarkers for SLE diagnosis. Those biomarkers were further validated in an independent cohort with high accuracy (AUC = 0.862 and 0.898 for protein and metabolite biomarkers respectively). This unbiased screening has led to the discovery of novel molecules for SLE disease activity assessment and SLE classification., Competing Interests: Declaration of Competing Interest J Du and L Kang are employed by the company Shanghai Biotree Biomedical Biotechnology Co., Ltd. The remaining authors declare that this study was conducted in the absence of any commercial or financial relationships., (Copyright © 2023. Published by Elsevier Inc.)

Introduction/objectives: To seek significant features of systemic lupus erythematosus (SLE) by utilizing bioinformatics analysis., Method: Liquid chromatography-tandem mass spectrometry (LC-MS/MS) was used to quantify lysine crotonylation (Kcr) and lysine 2-hydroxyisobutyrylation (Khib) in peripheral blood mononuclear cells (PBMCs) of systemic lupus erythematosus (SLE) patients and normal controls., Results: Seventy-six differentially modified proteins (DMPs) dually modified by Kcr and Khib were identified between SLE patients and healthy people. GO enrichment analysis prompted significant enrichment of seventy-six DMPs in MHC class II protein complex binding and leukocyte migration. KEGG pathways were enriched in antigen processing and presentation pathway and leukocyte transendothelial migration pathway. Six DMPs (CLTC, HSPA1B, HSPA8, HSP90AB1, HSPD1, and PDIA3) were identified in antigen processing and presentation pathway, of which HSPA8 was the core protein. Significant changes of Kcr and Khib in HSPA8 may increase ATP hydrolysis and promote antigen binding to MHC II molecule. In leukocyte transendothelial migration pathway, 7 DMPs (ACTN1, ACTN4, EZR, MSN, RAC1, RHOA, and VCL) were identified. MSN was the protein with the most modification sites in this pathway. In amino terminal ferm region of MSN, Kcr and Khib expression change may lead to the adhesion between leukocytes and endothelial cells, which was an important step of leukocyte migration., Conclusion: Kcr and Khib may promote the antigen presentation and jointly regulate the tissue damage mediated by leukocyte migration in SLE patients, which may play key roles in the pathogenesis of SLE probably. Key Points • Antigen processing and presentation and leukocyte transendothelial migration may play key roles in the pathogenesis of SLE., (© 2022. The Author(s).)

Systemic lupus erythematosus (SLE) is an autoimmune disorder characterized by immune complex deposition in multiple organs. Despite the severe symptoms caused by it, the underlying mechanisms of SLE, especially phosphorylation-dependent regulatory networks remain elusive. Herein, by combining high-throughput phosphoproteomics with bioinformatics approaches, we established the global phosphoproteome landscape of the peripheral blood mononuclear cells from a large number of SLE patients, including the remission stage (SLE_S), active stage (SLE_A), rheumatoid arthritis, and healthy controls, and thus a deep mechanistic insight into SLE signaling mechanism was yielded. Phosphorylation upregulation was preferentially in patients with SLE (SLE_S and SLE_A) compared with healthy controls and rheumatoid arthritis populations, resulting in an atypical enrichment in cell adhesion and migration signatures. Several specifically upregulated phosphosites were identified, and the leukocyte transendothelial migration pathway was enriched in the SLE_A group by expression pattern clustering analysis. Phosphosites identified by 4D-label-free quantification unveiled key kinases and kinase-regulated networks in SLE, then further validated by parallel reaction monitoring. Some of these validated phosphosites including vinculin S275, vinculin S579 and transforming growth factor beta-1-induced transcript 1 S68, primarily were phosphorylation of Actin Cytoskeleton -related proteins. Some predicted kinases including MAP3K7, TBK1, IKKβ, and GSK3β, were validated by Western blot using kinases phosphorylation sites-specific antibodies. Taken together, the study has yielded fundamental insights into the phosphosites, kinases, and kinase-regulated networks in SLE. The map of the global phosphoproteomics enables further understanding of this disease and will provide great help for seeking more potential therapeutic targets for SLE., Competing Interests: Conflict of interest All authors declare no competing interests., (Copyright © 2022. Published by Elsevier Inc.)

Introduction: Systemic lupus erythematosus (SLE) is a chronic autoimmune disease for which there is no cure. Effective diagnosis and precise assessment of disease exacerbation remains a major challenge., Methods: We performed peripheral blood mononuclear cell (PBMC) proteomics of a discovery cohort, including patients with active SLE and inactive SLE, patients with rheumatoid arthritis (RA), and healthy controls (HC). Then, we performed a machine learning pipeline to identify biomarker combinations. The biomarker combinations were further validated using enzyme-linked immunosorbent assays (ELISAs) in another cohort. Single-cell RNA sequencing (scRNA-seq) data from active SLE, inactive SLE, and HC PBMC samples further elucidated the potential immune cellular sources of each of these PBMC biomarkers., Results: Screening of the PBMC proteome identified 1023, 168, and 124 proteins that were significantly different between SLE vs. HC, SLE vs. RA, and active SLE vs. inactive SLE, respectively. The machine learning pipeline identified two biomarker combinations that accurately distinguished patients with SLE from controls and discriminated between active and inactive SLE. The validated results of ELISAs for two biomarker combinations were in line with the discovery cohort results. Among them, the six-protein combination (IFIT3, MX1, TOMM40, STAT1, STAT2, and OAS3) exhibited good performance for SLE disease diagnosis, with AUC of 0.723 and 0.815 for distinguishing SLE from HC and RA, respectively. Nine-protein combination (PHACTR2, GOT2, L-selectin, CMC4, MAP2K1, CMPK2, ECPAS, SRA1, and STAT2) showed a robust performance in assessing disease exacerbation (AUC=0.990). Further, the potential immune cellular sources of nine PBMC biomarkers, which had the consistent changes with the proteomics data, were elucidated by PBMC scRNAseq., Discussion: Unbiased proteomic quantification and experimental validation of PBMC samples from two cohorts of patients with SLE were identified as biomarker combinations for diagnosis and activity monitoring. Furthermore, the immune cell subtype origin of the biomarkers in the transcript expression level was determined using PBMC scRNAseq. These findings present valuable PBMC biomarkers associated with SLE and may reveal potential therapeutic targets., Competing Interests: Author LY was employed by Guangzhou Enttxs Medical Products Co., Ltd. Author BH was employed by Reproductive and Genetic Hospital of China International Trust and Investment Corporation (CITIC)-Xiangya. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Li, Ma, Liao, Qi, Meng, Cai, Dai, Cao, Dong, Krämer, Yun, Hocher, Hong, Liu, Tang, He, Yin and Dai.)

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease with multi-organ inflammation and defect, which is linked to many molecule mediators. Oxylipins as a class of lipid mediator have not been broadly investigated in SLE. Here, we applied targeted mass spectrometry analysis to screen the alteration of oxylipins in serum of 98 SLE patients and 106 healthy controls. The correlation of oxylipins to lupus nephritis (LN) and SLE disease activity, and the biomarkers for SLE classification, were analyzed. Among 128 oxylipins analyzed, 92 were absolutely quantified and 26 were significantly changed. They were mainly generated from the metabolism of several polyunsaturated fatty acids, including arachidonic acid (AA), linoleic acid (LA), docosahexanoic acid (DHA), eicosapentanoic acid (EPA) and dihomo-γ-linolenic acid (DGLA). Several oxylipins, especially those produced from AA, showed different abundance between patients with and without lupus nephritis (LN). The DGLA metabolic activity and DGLA generated PGE1, were significantly associated with SLE disease activity. Random forest-based machine learning identified a 5-oxylipin combination as potential biomarker for SLE classification with high accuracy. Seven individual oxylipin biomarkers were also identified with good performance in distinguishing SLE patients from healthy controls (individual AUC > 0.7). Interestingly, the biomarkers for differentiating SLE patients from healthy controls are distinct from the oxylipins differentially expressed in LN patients vs. non-LN patients. This study provides possibilities for the understanding of SLE characteristics and the development of new tools for SLE classification., Competing Interests: SZ and XY are employed by the company Shanghai Biotree Biomedical Biotechnology Co., Ltd. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 He, Ma, Tang, Zhong, Yuan, Zheng, Zeng, Chen, Liu, Hong, Dai, Yin and Dai.)

Background: Systemic lupus erythematosus (SLE) is an autoimmune illness caused by a malfunctioning immunomodulatory system. China has the second highest prevalence of SLE in the world, from 0.03% to 0.07%. SLE is diagnosed using a combination of immunological markers, clinical symptoms, and even invasive biopsy. As a result, genetic diagnostic biomarkers for SLE diagnosis are desperately needed., Method: From the Gene Expression Omnibus (GEO) database, we downloaded three array data sets of SLE patients' and healthy people's peripheral blood mononuclear cells (PBMC) (GSE65391, GSE121239 and GSE61635) as the discovery metadata (n SLE = 1315, n normal = 122), and pooled four data sets (GSE4588, GSE50772, GSE99967, and GSE24706) as the validate data set (n SLE = 146, n normal = 76). We screened the differentially expressed genes (DEGs) between the SLE and control samples, and employed the least absolute shrinkage and selection operator (LASSO) regression, and support vector machine recursive feature elimination (SVM-RFE) analyze to discover possible diagnostic biomarkers. The candidate markers' diagnostic efficacy was assessed using the receiver operating characteristic (ROC) curve. The reverse transcription quantitative polymerase chain reaction (RT-qPCR) was utilized to confirm the expression of the putative biomarkers using our own Chinese cohort (n SLE = 13, n normal = 10). Finally, the proportion of 22 immune cells in SLE patients was determined using the CIBERSORT algorithm, and the correlations between the biomarkers' expression and immune cell ratios were also investigated., Results: We obtained a total of 284 DEGs and uncovered that they were largely involved in several immune relevant pathways, such as type І interferon signaling pathway, defense response to virus, and inflammatory response. Following that, six candidate diagnostic biomarkers for SLE were selected, namely ABCB1, EIF2AK2, HERC6, ID3, IFI27, and PLSCR1, whose expression levels were validated by the discovery and validation cohort data sets. As a signature, the area under curve (AUC) values of these six genes reached to 0.96 and 0.913, respectively, in the discovery and validation data sets. After that, we checked to see if the expression of ABCB1, IFI27, and PLSCR1 in our own Chinese cohort matched that of the discovery and validation sets. Subsequently, we revealed the potentially disturbed immune cell types in SLE patients using the CIBERSORT analysis, and uncovered the most relevant immune cells with the expression of ABCB1, IFI27, and PLSCR1., Conclusion: Our study identified ABCB1, IFI27, and PLSCR1 as potential diagnostic genes for Chinese SLE patients, and uncovered their most relevant immune cells. The findings in this paper provide possible biomarkers for diagnosing Chinese SLE patients., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Zhong, Zhang, Hong, Zeng, Chen, Liao, Cai, Xu, Wang, Liu, Tang and Dai.)

The immune cells and the repertoire of T cells and B cells play an important role in the pathogenesis of systemic lupus erythematosus (SLE). Exploring their expression and distribution in SLE can help us better understand this lethal autoimmune disease. In this study, we used a single-cell 5' RNA sequence and single-cell T cell receptor (TCR)/B cell receptor (BCR) to study the immune cells and the repertoire from ten SLE patients and the paired normal controls (NC). The results showed that 9732 cells correspondence to 12 cluster immune cell types were identified in NC, whereas 11042 cells correspondence to 16 cluster immune cell types were identified in SLE. The results demonstrated that neutrophil, macrophage, and dendritic cells were accumulated in SLE by annotating the immune cell types. Besides, the bioinformatics analysis of differentially expressed genes (DEGs) in these cell types indicates their role in inflammation response. In addition, patients with SLE showed increased TCR and BCR clonotypes compared with the healthy controls. Furthermore, patients with SLE showed biased usage of TCR and BCR V(D)J genes. Taken together, we characterized the transcriptome and TCR/BCR immune repertoire profiles of SLE patients, which may provide a new avenue for the diagnosis and treatment of SLE.

Background: Systemic lupus erythematosus (SLE) is an autoimmune disease with a complicated pathogenesis, and its aetiology has not been clearly unveiled. The lack of effective diagnosis and treatment methods makes it necessary to explore the molecular mechanism of SLE. We aimed to identify some critical signalling pathways and key competing endogenous RNAs (ceRNAs) underlying the molecular mechanism of SLE and to map out the systematic signalling networks by integrating the data on different kinds of RNAs., Methods: Peripheral blood mononuclear cells (PBMCs) were collected from both SLE patients and healthy subjects, RNA was extracted from the PBMCs, and RNA libraries including ribosomal RNA-depleted strand-specific libraries and small RNA libraries were built for deep RNA sequencing (RNA-seq). RNA-seq yielded differential expression profiles of lncRNAs/circRNAs/miRNAs/mRNAs related to SLE. The DAVID database (v. 6.8) was employed for Gene Ontology (GO) and KEGG pathway analysis. ceRNA networks (circRNA/lncRNA-miRNA-mRNA) were constructed and visualized using Cytoscape software (v. 3.5.0). The TargetScan and miRanda databases were used to predict target relationships in ceRNA networks. qRT-PCR was used to verify our data., Results: Differential expression of ceRNAs related to SLE was detected in SLE patients' PBMCs: 644 mRNAs (384 upregulated, 260 downregulated), 326 miRNAs (223 upregulated, 103 downregulated), 221 lncRNAs (79 upregulated, 142 downregulated), and 31 circRNAs (21 upregulated, 10 downregulated). We drew ceRNA signalling networks made up of the differentially expressed mRNAs/miRNAs/lncRNAs/circRNAs mentioned above, and the hub genes included IRF5, IFNAR2, TLR7, IRAK4, STAT1, STAT2, C2, and Tyk2. These hub genes were involved in ceRNA signalling pathways, such as the IL-17 signalling pathway and type I interferon signalling pathway., Conclusions: We explored the differential expression profiles of various kinds of ceRNAs and integrated signalling networks constructed by ceRNAs. Our findings offer new insights into the pathogenesis of SLE and hint at therapeutic strategies., (© 2021. The Author(s).)

Recent studies have demonstrated a central role for plasma cells in the development of autoimmune diseases, such as systemic lupus erythematosus (SLE). Currently, both the phenotypic features and functional regulation of autoreactive plasma cells during SLE pathogenesis remain largely unclear. In this study, we first found that a major subset of IL-17 receptor-expressing plasma cells potently produced anti-dsDNA IgG upon IL-17A (IL-17) stimulation in SLE patients and lupus mice. Using a humanized lupus mouse model, we showed that the transfer of Th17 cell-depleted PBMCs from lupus patients resulted in a significantly reduced plasma cell response and attenuated renal damage in recipient mice compared to the transfer of total SLE PBMCs. Moreover, long-term BrdU incorporation in lupus mice detected highly enriched long-lived BrdU + subsets among IL-17 receptor-expressing plasma cells. Lupus mice deficient in IL-17 or IL-17 receptor C (IL-17RC) exhibited a diminished plasma cell response and reduced autoantibody production with attenuated renal damage, while the adoptive transfer of Th17 cells triggered the plasma cell response and renal damage in IL-17-deficient lupus mice. In reconstituted chimeric mice, IL-17RC deficiency resulted in severely impaired plasma cell generation but showed no obvious effect on germinal center B cells. Further mechanistic studies revealed that IL-17 significantly promoted plasma cell survival via p38-mediated Bcl-xL transcript stabilization. Together, our findings identified a novel function of IL-17 in enhancing plasma cell survival for autoantibody production in lupus pathogenesis, which may provide new therapeutic strategies for the treatment of SLE.

Objective: Systemic lupus erythematosus (SLE) is a complex autoimmune disease, and various immune cells are involved in the initiation, progression, and regulation of SLE. Our goal was to reveal the chromatin accessibility landscape of peripheral blood mononuclear cells (PBMCs) in SLE patients at single-cell resolution and identify the transcription factors (TFs) that may drive abnormal immune responses., Methods: The assay for transposase accessible chromatin in single-cell sequencing (scATAC-seq) method was applied to map the landscape of active regulatory DNA in immune cells from SLE patients at single-cell resolution, followed by clustering, peak annotation and motif analysis of PBMCs in SLE., Results: Peripheral blood mononuclear cells were robustly clustered based on their types without using antibodies. We identified twenty patterns of TF activation that drive abnormal immune responses in SLE patients. Then, we observed ten genes that were highly associated with SLE pathogenesis by altering T cell activity. Finally, we found 12 key TFs regulating the above six genes ( CD83 , ELF4 , ITPKB , RAB27A , RUNX3 , and ZMIZ1 ) that may be related to SLE disease pathogenesis and were significantly enriched in SLE patients (p <0.05, FC >2). With qPCR experiments on  CD83 ,  ELF4 ,  RUNX3 , and  ZMIZ1  in B cells, we observed a significant difference in the expression of genes ( ELF4 ,  RUNX3 , and  ZMIZ1 ), which were regulated by seven TFs (EWSR1-FLI1, MAF, MAFA, NFIB, NR2C2 (var. 2), TBX4, and TBX5). Meanwhile, the seven TFs showed highly accessible binding sites in SLE patients., Conclusions: These results confirm the importance of using single-cell sequencing to uncover the real features of immune cells in SLE patients, reveal key TFs in SLE-PBMCs, and provide foundational insights relevant for epigenetic therapy., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Yu, Hong, Wu, Zheng, Zeng, Dai, Yin, Liu, Tang and Dai.)

Systemic lupus erythematosus (SLE) is a chronic inflammatory autoimmune disease characterized by the production of multiple autoimmune antibodies and potentially involves any organ or tissue with a broad range of clinical manifestations. Conventional therapy still utilizes glucocorticoids and immunosuppressants. However, some patients show inadequate responses to glucocorticoids and immunosuppression, which may induce secondary immune dysfunction and severe infection as well as lead to an increased tumor risk. The lack of in vitro models has hampered progress in understanding and treating SLE. Patient-derived induced pluripotent stem cells (iPSCs) may provide a unique opportunity for modeling in vitro diseases as well as a platform for drug screening in individual patients. We isolated peripheral blood mononuclear cells from blood to explore the establishment of an in vitro model platform for SLE and directly purified CD34+ cells and seeded them for expansion. CD34+ cells were forced to express seven pluripotency factors, OCT4, SOX2, NANOG, LIN28, c-MYC, KLF4, and SV40LT, through transduction in lentiviral vectors. The morphological characteristics of induced pluripotent stem-like cells, such as prominent nucleoli and a high nucleus-to-cytoplasm ratio, were observed. The pluripotency of established SLE patient-derived iPSCs was confirmed by the expression of embryonic stem cell (ESC) markers and the ability of cells to differentiate into multiple cell lines. SLE patient-derived iPSCs exhibited human ESC properties, including morphology; growth characteristics; expression of pluripotency, genes, and surface markers; and teratoma formation. In conclusion, we generated SLE patient-derived iPSCs and validated their pluripotency. This study is a first but critical step that can provide a model platform for research aimed at understanding the SLE mechanism, which may lead to the discovery of new targets or compounds for the treatment of this disease.

Systemic lupus erythematosus (SLE) is a heterogeneous, autoimmune disease that can affect multiple organs and systems such as skin, joints, kidneys, hematologic system or central nervous system. Women of childbearing age are the predominate population affected by SLE. In this study, we generated an iPS cell line from a 30-year-old female who was pregnant with a gestational age of 27 weeks and diagnosed with severe preeclampsia, SLE and psoriasis. This patient-specific iPSC line will be useful to create the specific disease model of systemic lupus erythematosus to elucidate the pathological mechanisms and develop drug screening., (Copyright © 2021 The Authors. Published by Elsevier B.V. All rights reserved.)

Systemic lupus erythematosus (SLE) is a systemic autoimmune disease that affects thousands of people worldwide. Recently, alterations in metabolism and gut microbiome have emerged as key regulators of SLE pathogenesis. However, it is not clear about the coordination of gut commensal bacteria and SLE metabolism. Here, by integrating 16S sequencing and metabolomics data, we characterized the gut microbiome and fecal and serum metabolome alterations in patients with SLE. Microbial diversity sequencing revealed gut microflora dysbiosis in SLE patients with significantly increased beta diversity. The metabolomics profiling identified 43 and 55 significantly changed metabolites in serum and feces samples in SLE patients. Notably, lipids accounted for about 65% altered metabolites in serum, highlighted the disruption of lipid metabolism. Integrated correlation analysis provided a link between the gut microbiome and lipid metabolism in patients with SLE, particularly according to regulate the conversion of primary bile acids to secondary bile acids. Overall, our results illustrate the perturbation of the gut microbiome and metabolome in SLE patients which may facilitate the development of new SLE interventions., (Copyright © 2020 He, Chan, Hong, Zheng, Zhu, Yin, Dai, Tang, Liu and Dai.)

Systemic lupus erythematosus (SLE), an autoimmune disease that causes multiorgan injury, has an unclear etiology and complex pathogenesis. Numerous studies have found abnormal alterations in mRNAs, proteins and/or metabolites in SLE patients. These findings have extended our understanding of the pathogenesis of SLE. Novel omics techniques, such as transcriptome, proteome and metabolome profiling, can identify and quantify large numbers of biomarkers of human diseases. However, in most cases, biological reactions are the consequences of interactions among genes, proteomes, and metabolites. Single biomolecules or signaling pathways cannot fully explain biological traits or functions. Therefore, integrative multi-omics analysis can help us systematically comprehend the intrinsic molecular mechanisms underlying biological function and pathogenesis. Integrating transcriptome, proteome, and metabolome KEGG enrichment analysis data will expand our knowledge of the pathogenesis of SLE. This review discusses the application, research progress and outlook on integrative multi-omics analysis in SLE research.

Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by excessive autoantibody production and multi-organ involvement. Although the etiology of SLE still remains unclear, recent studies have characterized several pathogenic B cell subsets and regulatory B cell subsets involved in the pathogenesis of SLE. Among pathogenic B cell subsets, age-associated B cells (ABCs) are a newly identified subset of autoreactive B cells with T-bet-dependent transcriptional programs and unique functional features in SLE. Accumulation of T-bet + CD11c + ABCs has been observed in SLE patients and lupus mouse models. In addition, innate-like B cells with the autoreactive B cell receptor (BCR) expression and long-lived plasma cells with persistent autoantibody production contribute to the development of SLE. Moreover, several regulatory B cell subsets with immune suppressive functions have been identified, while the impaired inhibitory effects of regulatory B cells have been indicated in SLE. Thus, further elucidation on the functional features of B cell subsets will provide new insights in understanding lupus pathogenesis and lead to novel therapeutic interventions in the treatment of SLE.

Objectives: In patients with systemic lupus erythematosus (SLE), immune tolerance breakdown leads to autoantibody production and immune-complex glomerulonephritis. This study aimed to identify pathogenic plasma cells (PC) in the development of lupus nephritis., Methods: PC subsets in peripheral blood and renal tissue of patients with SLE and lupus mice were examined by flow cytometry and confocal microscopy, respectively. Sorting-purified PCs from lupus mice were adoptively transferred into Rag2 -deficient recipients, in which immune-complex deposition and renal pathology were investigated. In culture, PCs from lupus mice and patients with SLE were treated with a TLR4 inhibitor and examined for autoantibody secretion by enzyme-linked immunospot assay (ELISPOT). Moreover, lupus mice were treated with a TLR4 inhibitor, followed by the assessment of serum autoantibody levels and glomerulonephritis activity., Results: The frequencies of TLR4 + CXCR4 + PCs in peripheral blood and renal tissue were found significantly increased with the potent production of anti-dsDNA IgG, which were associated with severe renal damages in patients with SLE and mice with experimental lupus. Adoptive transfer of TLR4 + CXCR4 + PCs from lupus mice led to autoantibody production and glomerulonephritis development in Rag2 -deficient recipients. In culture, TLR4 + CXCR4 + PCs from both lupus mice and patients with SLE showed markedly reduced anti-dsDNA IgG secretion on TLR4 blockade. Moreover, in vivo treatment with TLR4 inhibitor significantly attenuated autoantibody production and renal damages in lupus mice., Conclusions: These findings demonstrate a pathogenic role of TLR4 + CXCR4 + PCs in the development of lupus nephritis and may provide new therapeutic strategies for the treatment of SLE., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2018. No commercial re-use. See rights and permissions. Published by BMJ.)

Objective: The impact of pregnancy on lupus activity has been controversial especially in Chinese women. Research looking at predictive factors in this population are sparse. The aim of this study was therefore twofold: to determine the frequencies of abnormal pregnancy outcomes in a Chinese cohort and to identify clinical and laboratory factors predicting adverse fetal and maternal outcomes in Chinese women with systemic lupus erythematosus., Study Design: Data of 111 pregnancies of 105 systemic lupus erythematosus (SLE) patients from January 1990 to December 2008 in Peking Union Medical College Hospital in Beijing were analyzed retrospectively. Univariate analysis using chi-square test and logistic regression was used to assess the predictive value of each variable on binary outcomes. Lupus activity was based on SLE Disease Activity Index (SLEDAI) criteria., Results: There were 23 elective, 2 spontaneous abortions, and 5 stillbirths, with 81 pregnancies resulting in live births including two multiple gestations. Three neonatal deaths were reported. Fetal loss rate including neonatal death was 11.1%. Fetal loss in active SLE group (17.0%) was significantly higher than those in inactive group (2.0%) (P = 0.047). The incidence of premature birth in active SLE group was 25/47 (53.2%), which is significantly higher than those in inactive group (3/34, 8.8%) (P < 0.001). Small for gestational age (SGA) was more common in active SLE group with incidence of 40.0% compared to 5.6% in inactive group (P < 0.001). Five fetal malformations were recorded (6.0%), including three fetal heart malformations (one complete heart block, one tetralogy of Fallot, and one atrial septal defect) and two multiple fetal malformations, which were significantly higher than general population. Among 25 pregnancies that were in active stage at conception, 14 (56%) deteriorated during pregnancy. Of the 68 pregnancies that were stable at conception, 26 (38%) flared during pregnancy or postpartum. Preeclampsia/eclampsia (OR = 14.83, 95% CI: 3.83-57.41) and thrombocytopenia (OR = 4.43, 95% CI: 1.12-17.60) were significant predictors of fetal loss; preeclampsia/eclampsia (OR = 8.04, 95% CI: 2.00-32.34) and active SLE (OR = 19.90, 95% CI: 2.38-166.27) were significantly associated with preterm birth; preeclampsia/eclampsia (OR = 8.92, 95% CI: 2.25-35.44) and thrombocytopenia (OR = 4.03, 95% CI: 1.24-17.25) were also significant predictors of maternal SLE flare-up., Conclusion: In general, lupus in pregnancy in the Chinese population is generally similar to other cohorts. Pregnancies can be successful in most women with SLE. However, an increase in SLE activity can occur in a significant number of patients, even those who are well controlled. Adverse fetal outcome including fetal loss, preterm birth, and SGA increases significantly with SLE flares during pregnancy with preeclampsia/eclampsia, thrombocytopenia, and active SLE serving independent predictors of adverse fetal and maternal outcome. Fetal echo should not just for heart block but for structural abnromalities as the structural malformation rate was significantly higher than general population, especially congenital heart disease.