scholarly journals Effect of Leflunomide on the Abnormal Expression of Lipid Rafts and F-Actin in B Lymphocytes from Patients with Systemic Lupus Erythematosus

2015 ◽  
Vol 2015 ◽  
pp. 1-8 ◽  
Author(s):  
Guang Fu Dong ◽  
Xiao Zhang ◽  
De Ning He ◽  
Ling Li ◽  
Guang Feng Zhang

Purposes. To investigate the possible changes in B cell subsets and in B cell expression patterns of lipid rafts (LRs) and F-actin in patients with SLE and whether leflunomide treatment may have effect on these changes.Methods. The B cell subsets and LRs expression were determined by flow cytometry and confocal microscopy, and F-actin expression was examined by confocal microscopy.Results. CD27+IgD+B cell subsets were significantly decreased while CD38+CD95+B cell subsets increased in SLE patients. The LRs levels of B cells were remarkably increased and positively correlated with SLEDAI and anti-dsDNA titer in SLE patients. The expression level of LRs was significantly higher in CD38+B cells than CD38−B cells and negatively correlated with C3 levels. The increased expression of LRs was associated with reduced expression of F-actin in the B cells from active SLE patients. Furthermore, in vitro treatment of the cells with A771726 reduced the expression level of LRs, attenuated the overaggregation of LRs, and normalized the distribution of F-actin.Conclusions. There were abnormalities in B cell subsets and LRs and F-actin expression of B cell from SLE patients. Modulation of B cell expression of LRs and F-actin by LEF could be a potential therapeutic target for SLE.

Blood ◽  
2007 ◽  
Vol 110 (11) ◽  
pp. 3586-3586
Author(s):  
Jan-Lukas Robertus ◽  
Miao Wang ◽  
Geert Harms ◽  
Tjasso Blokzijl ◽  
Rikst Nynke Schakel ◽  
...  

Abstract Introduction Amplification of chromosome 13q31 is a frequent occurrence in lymphoma and solid tumors. The C13orf25 gene at 13q31.3 is the primary miRNA transcript for seven miRNAs. This specific cluster of miRNAs is sequentially related to the homologous miR-106a-92 cluster on chromosome X and the miR-106b-25 cluster on chromosome 7. The miR17-92 cluster has been shown to be over expressed in various non-Hodgkin Lymphoma (NHL). As a specific group of miRNAs which are derived from the same primary miRNA transcript, each miRNA in the cluster may be expected to show a similar expression level. However expression patterns vary markedly in different cancers. Aim of study To compare the expression pattern of the C13orf25 gene and the miRNAs in normal and malignant B-cells. Methods and Materials 51 cases of Ann Abour stage I and II primary diffuse large B-cell lymphoma (DLBCL) were collected together with 29 cases of B-CLL. All samples were examined for expression of miRNA miR-18a, -19, -20a, 17-3p, -17-5p and -92 and the C13orf 25 gene. Expression levels of the mature miRNAs were determined by qRT-PCR using Taqman miRNA assays. The level of C13orf25 was also determined by qRT-PCR using random primers and a Sybergreen probe. Results were compared by using 2−ΔCt and 2−ΔΔCt. Normal B-cell subpopulations were isolated from fresh tonsils obtained during routine pediatric tonsillectomies. B-cell subsets were stained accordingly and sorted by FACS. Results Comparison of the miRNA pattern (2−ΔCt) revealed that DLBCL have the highest expression level of miR-19b and that B-CLL shows a relative high expression level of miR-92. Normal naïve, germinal center and memory B-cells all show a similar expression pattern with miR-92 having the highest expression level. Remarkably a low expression level of miR-19b is seen in all three B-cell populations in contrast to DLBCL. Comparing the relative expression levels (2−ΔΔCt) of both NHL for each individual miRNA shows that B-CLL has a significantly higher level of expression for miR-19a. In DLBCL miR-17-5p, miR-18a and miR-20a have the highest expression levels. Currently 20 Mantle cell lymphoma are also being analyzed for the C13orf25 miRNAs cluster. Conclusion Our results show that both of the NHL B-cell malignancies and the B-cell subsets have different expression patterns of the individual levels of the 7 miRNAs contained in the same C13orf25 cluster. The relative expression levels of certain miRNAs from the same primary transcript are different in various NHL. Although there are no marked differences in the normal B-cell subsets for the C13orf25 cluster, further profiling revealed various different expression levels of other miRNAs. These findings may point towards a difference in processing efficiency or stability of miRNAs in the C13orf25 cluster leading to differences in pathogenesis specific for each malignancy even in cells of similar origin and differentiation stage.


2020 ◽  
Vol 79 (Suppl 1) ◽  
pp. 4-5
Author(s):  
A. Aue ◽  
F. Szelinski ◽  
S. Weißenberg ◽  
A. Wiedemann ◽  
T. Rose ◽  
...  

Background:Systemic lupus erythematosus (SLE) is characterized by two pathogenic key signatures, type I interferon (IFN) (1.) and B-cell abnormalities (2.). How these signatures are interrelated is not known. Type I-II IFN trigger activation of Janus kinase (JAK) – signal transducer and activator of transcription (STAT).Objectives:JAK-STAT inhibition is an attractive therapeutic possibility for SLE (3.). We assess STAT1 and STAT3 expression and phosphorylation at baseline and after IFN type I and II stimulation in B-cell subpopulations of SLE patients compared to other autoimmune diseases and healthy controls (HD) and related it to disease activity.Methods:Expression of STAT1, pSTAT1, STAT3 and pSTAT3 in B and T-cells of 21 HD, 10 rheumatoid arthritis (RA), 7 primary Sjögren’s (pSS) and 22 SLE patients was analyzed by flow cytometry. STAT1 and STAT3 expression and phosphorylation in PBMCs of SLE patients and HD after IFNα and IFNγ incubation were further investigated.Results:SLE patients showed substantially higher STAT1 but not pSTAT1 in B and T-cell subsets. Increased STAT1 expression in B cell subsets correlated significantly with SLEDAI and Siglec-1 on monocytes, a type I IFN marker (4.). STAT1 activation in plasmablasts was IFNα dependent while monocytes exhibited dependence on IFNγ.Figure 1.Significantly increased expression of STAT1 by SLE B cells(A) Representative histograms of baseline expression of STAT1, pSTAT1, STAT3 and pSTAT3 in CD19+ B cells of SLE patients (orange), HD (black) and isotype controls (grey). (B) Baseline expression of STAT1 and pSTAT1 or (C) STAT3 and pSTAT3 in CD20+CD27-, CD20+CD27+ and CD20lowCD27high B-lineage cells from SLE (orange) patients compared to those from HD (black). Mann Whitney test; ****p≤0.0001.Figure 2.Correlation of STAT1 expression by SLE B cells correlates with type I IFN signature (Siglec-1, CD169) and clinical activity (SLEDAI).Correlation of STAT1 expression in CD20+CD27- näive (p<0.0001, r=0.8766), CD20+CD27+ memory (p<0.0001, r=0.8556) and CD20lowCD27high (p<0.0001, r=0.9396) B cells from SLE patients with (A) Siglec-1 (CD169) expression on CD14+ cells as parameter of type I IFN signature and (B) lupus disease activity (SLEDAI score). Spearman rank coefficient (r) was calculated to identify correlations between these parameters. *p≤0.05, **p≤0.01. (C) STAT1 expression in B cell subsets of a previously undiagnosed, active SLE patient who was subsequently treated with two dosages of prednisolone and reanalyzed.Conclusion:Enhanced expression of STAT1 by B-cells candidates as key node of two immunopathogenic signatures (type I IFN and B-cells) related to important immunopathogenic pathways and lupus activity. We show that STAT1 is activated upon IFNα exposure in SLE plasmablasts. Thus, Jak inhibitors, targeting JAK-STAT pathways, hold promise to block STAT1 expression and control plasmablast induction in SLE.References:[1]Baechler EC, Batliwalla FM, Karypis G, Gaffney PM, Ortmann WA, Espe KJ, et al. Interferon-inducible gene expression signature in peripheral blood cells of patients with severe lupus. Proc Natl Acad Sci U S A. 2003;100(5):2610-5.[2]Lino AC, Dorner T, Bar-Or A, Fillatreau S. Cytokine-producing B cells: a translational view on their roles in human and mouse autoimmune diseases. Immunol Rev. 2016;269(1):130-44.[3]Dorner T, Lipsky PE. Beyond pan-B-cell-directed therapy - new avenues and insights into the pathogenesis of SLE. Nat Rev Rheumatol. 2016;12(11):645-57.[4]Biesen R, Demir C, Barkhudarova F, Grun JR, Steinbrich-Zollner M, Backhaus M, et al. Sialic acid-binding Ig-like lectin 1 expression in inflammatory and resident monocytes is a potential biomarker for monitoring disease activity and success of therapy in systemic lupus erythematosus. Arthritis Rheum. 2008;58(4):1136-45.Disclosure of Interests:Arman Aue: None declared, Franziska Szelinski: None declared, Sarah Weißenberg: None declared, Annika Wiedemann: None declared, Thomas Rose: None declared, Andreia Lino: None declared, Thomas Dörner Grant/research support from: Janssen, Novartis, Roche, UCB, Consultant of: Abbvie, Celgene, Eli Lilly, Roche, Janssen, EMD, Speakers bureau: Eli Lilly, Roche, Samsung, Janssen


2021 ◽  
Vol 23 (1) ◽  
Author(s):  
Kittikorn Wangriatisak ◽  
Chokchai Thanadetsuntorn ◽  
Thamonwan Krittayapoositpot ◽  
Chaniya Leepiyasakulchai ◽  
Thanitta Suangtamai ◽  
...  

Abstract Background Autoreactive B cells are well recognized as key participants in the pathogenesis of systemic lupus erythematosus (SLE). However, elucidating the particular subset of B cells in producing anti-dsDNA antibodies is limited due to their B cell heterogeneity. This study aimed to identify peripheral B cell subpopulations that display autoreactivity to DNA and contribute to lupus pathogenesis. Methods Flow cytometry was used to detect total B cell subsets (n = 20) and DNA autoreactive B cells (n = 15) in SLE patients’ peripheral blood. Clinical disease activities were assessed in SLE patients using modified SLEDAI-2 K and used for correlation analyses with expanded B cell subsets and DNA autoreactive B cells. Results The increases of circulating double negative 2 (DN2) and activated naïve (aNAV) B cells were significantly observed in SLE patients. Expanded B cell subsets and DNA autoreactive B cells represented a high proportion of aNAV B cells with overexpression of CD69 and CD86. The frequencies of aNAV B cells in total B cell populations were significantly correlated with modified SLEDAI-2 K scores. Further analysis showed that expansion of aNAV DNA autoreactive B cells was more related to disease activity and serum anti-dsDNA antibody levels than to total aNAV B cells. Conclusion Our study demonstrated an expansion of aNAV B cells in SLE patients. The association between the frequency of aNAV B cells and disease activity patients suggested that these expanded B cells may play a role in SLE pathogenesis.


2019 ◽  
Vol 20 (23) ◽  
pp. 6021 ◽  
Author(s):  
Kongyang Ma ◽  
Wenhan Du ◽  
Xiaohui Wang ◽  
Shiwen Yuan ◽  
Xiaoyan Cai ◽  
...  

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.


Rheumatology ◽  
2020 ◽  
Vol 59 (9) ◽  
pp. 2616-2624
Author(s):  
Svenja Henning ◽  
Wietske M Lambers ◽  
Berber Doornbos-van der Meer ◽  
Wayel H Abdulahad ◽  
Frans G M Kroese ◽  
...  

Abstract Objectives Incomplete SLE (iSLE) patients display symptoms typical for SLE but have insufficient criteria to fulfil the diagnosis. Biomarkers are needed to identify iSLE patients that will progress to SLE. IFN type I activation, B-cell-activating factor (BAFF) and B-cell subset distortions play an important role in the pathogenesis of SLE. The aim of this cross-sectional study was to investigate whether B-cell subsets are altered in iSLE patients, and whether these alterations correlate with IFN scores and BAFF levels. Methods iSLE patients (n = 34), SLE patients (n = 41) with quiescent disease (SLEDAI ≤4) and healthy controls (n = 22) were included. Proportions of B-cell subsets were measured with flow cytometry, IFN scores with RT-PCR and BAFF levels with ELISA. Results Proportions of age-associated B-cells were elevated in iSLE patients compared with healthy controls and correlated with IgG levels. In iSLE patients, IFN scores and BAFF levels were significantly increased compared with healthy controls. Also, IFN scores correlated with proportions of switched memory B-cells, plasma cells and IgG levels, and correlated negatively with complement levels in iSLE patients. Conclusion In this cross-sectional study, distortions in B-cell subsets were observed in iSLE patients and were correlated with IFN scores and IgG levels. Since these factors play an important role in the pathogenesis of SLE, iSLE patients with these distortions, high IFN scores, and high levels of IgG and BAFF may be at risk for progression to SLE.


2012 ◽  
Vol 2012 ◽  
pp. 1-8 ◽  
Author(s):  
Syuichi Koarada ◽  
Yoshifumi Tada ◽  
Rie Suematsu ◽  
Sachiko Soejima ◽  
Hisako Inoue ◽  
...  

This study aimed to investigate phenotype of RP105(−) B cell subsets in patients with systemic lupus erythematosus (SLE). Flow cytometry was used for phenotyping RP105-negaive B cell subsets. Based on CD19, RP105, and CD138 expression, RP105(−) B cells consist of at least 5 subsets of late B cells, including CD19(+)RP105(int), CD19(+) RP105(−), CD19(low) RP105(−) CD138(−), CD19(low) RP105(−)CD138(int), and CD19(low) RP105(−) CD138(++) B cells. Especially, CD19(+)RP105(int) and CD19(low) RP105(−)CD138(int) B cells are significantly larger than other RP105(−) B cell subsets in SLE. By comparison of RP105(−) B cell subsets between patients with SLE and normal subjects, these subsets were detectable even in normal subjects, but the percentages of RP105(−) B cell subsets were significantly larger in SLE. The phenotypic analysis of RP105(−) B cell subsets suggests dysregulation of later B cell subsets in SLE and may provide new insights into understanding regulation of B cells in human SLE.


2021 ◽  
Author(s):  
Franziska Szelinski ◽  
Ana-Luisa Stefanski ◽  
Annika Wiedemann ◽  
Eva Schrezenmeier ◽  
Hector Rincon-Arevalo ◽  
...  

B cells play a critical role in the pathogenesis of systemic lupus erythematosus (SLE). We analysed two independent cohorts of healthy donors and SLE patients using a combined approach of flow and mass cytometry. We have found that IgD-CD27+ switched and atypical IgD-CD27- memory B cells, which are increased in SLE, represent heterogeneous populations composed each of three different subsets, such as CXCR5+CD19int, CXCR5-CD19high and CXCR5-CD19low. Here, we characterize a hitherto unknown antigen-experienced CXCR5-CD19low B cell subsets enhanced in SLE and carrying a plasmablast (PB) phenotype enriched for switched immunoglobulins, and expressing CD38, CD95, CD71, PRDM1, XBP-1, and IRF4. CXCR5-CD19low resemble activated B cells with a characteristically diminished B cell receptor responsiveness. CXCR5-CD19low B cells increased with PB frequencies in SLE and upon BNT162b2 vaccination suggesting their interrelationship. Our data suggest that CXCR5-CD19low B cells are precursors of plasmablasts, thus co-targeting this subset may have therapeutic value in SLE.


2022 ◽  
Author(s):  
Mineto Ota ◽  
Masahiro Nakano ◽  
Yasuo Nagafuchi ◽  
Satomi Kobayashi ◽  
Hiroaki Hatano ◽  
...  

Despite involvement of B cells in the pathogenesis of immune-mediated diseases, biological mechanisms underlying their function are scarcely understood. To overcome this gap, comprehensive analysis of the B cell repertoire is essential. Here, we cataloged and investigated the repertoire of five B cell subsets from 595 cases under immune-mediated diseases and health. CDR-H3 length among naive B cells was shortened among autoimmune diseases in an interferon signature-dependent manner. VDJ gene usage was skewed especially in plasmablasts and unswitched-memory B cells of systemic lupus erythematosus patients with frequent usage of VDJ genes used mainly in naive B cells and not unswitched-memory B cells of healthy controls. We developed a scoring system for this skewing, and it correlated with peripheral helper T cell transcriptomic signatures and disease activity and decreased after belimumab treatment. Moreover, genetic association analysis identified three molecules possibly involved in somatic hyper-mutation processes in humans. Our multimodal repertoire analysis brings new insights to B cell biology.


2020 ◽  
Author(s):  
Yang Lu ◽  
Qingqing Zhu ◽  
Yun Li ◽  
Qiyi Wang ◽  
Chao Jiang ◽  
...  

Abstract Background: Programmed death 1 (PD-1) is an immunoregulatory receptor that inhibits T cell activation and proliferation upon binding to its cognate ligand (PD-L1). However, the role of the PD-1/PD-L1 axis in B cell function, especially in inflammatory and autoimmune disorders, is less clear. The aim of this study was to analyze the PD-1 expression patterns on multiple B cell subpopulations isolated from systemic lupus erythematosus (SLE) patients, and determine their clinical relevance. Results: The frequency of B cells increased significantly in patients with active SLE compared with healthy controls and patients with inactive SLE. In particular, the frequencies of the IgD CD27 and IgD CD27high (plasmablast cells) subpopulations were significantly higher in the patients compared to healthy individuals. Interestingly, the patients with active SLE harbored an increased proportion of the PD-1+ B cells, which correlated significantly with the disease severity (SLEDAI scores), incidence of lupus nephritis, and the circulating levels of autoantibodies and complement factors. Furthermore, the primary PD-1+ B cells isolated from the peripheral blood of SLE patients proliferated faster and secreted more anti-dsDNA antibodies and immunoglobulins in vitro compared to the PD-1+/- B cells from healthy controls. Conclusions: PD-1 is overexpressed on all B cell subpopulations of SLE patients and associated with disease progression.


1997 ◽  
Vol 185 (7) ◽  
pp. 1317-1326 ◽  
Author(s):  
Linda Spatz ◽  
Vladimir Saenko ◽  
Andrey Iliev ◽  
Lori Jones ◽  
Larisa Geskin ◽  
...  

Two major mechanisms for the regulation of autoreactive B cells that arise in the bone marrow are functional silencing (anergy) and deletion. Studies to date suggest that low avidity interactions between B cells and autoantigen lead to B cell silencing, whereas high avidity interactions lead to deletion. Anti–double stranded (ds) DNA antibodies represent a pathogenic autospecificity in Systemic Lupus Erythematosus (SLE). An understanding of their regulation is critical to an understanding of SLE. We now demonstrate in a transgenic model in which mice express the heavy chain of a potentially pathogenic anti-DNA antibody that antibody affinity for dsDNA does not alone determine the fate of anti-dsDNA B cells. B cells making antibodies with similar affinities for dsDNA are regulated differently, depending on light chain usage. A major implication of this observation is that dsDNA may not be the self antigen responsible for cell fate determinations of anti-dsDNA B cells. Light chain usage may determine antigenic crossreactivity, and cross-reactive antigens may regulate B cells that also bind dsDNA.


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