Associations between interleukin 1 polymorphisms and susceptibility to systemic lupus erythematosus: a meta-analysis

B cell activation and autoantibody production in autoimmune diseases

B cells are central players in the immune system, responsible for producing antibodies and modulating immune responses. This review explores the intricate relationship between aberrant B cell activation and the development of autoimmune diseases, emphasizing the essential role of B cells in these conditions. We also summarize B cell receptor signaling and Toll-like receptor signaling in B cell activation, as well as their association with autoimmune diseases, shedding light on the molecular mechanisms behind these associations. Additionally, we explore the clinical observations involving B cell activation and their significance in autoimmune disease management. Various clinical studies related to B cell-targeted therapies are also discussed, offering insights into potential avenues for improving treatment strategies. Overall, this review serves as a resource for researchers and clinicians in the field of immunology and autoimmune diseases, providing a general view of B cell signaling and its role in autoimmunity.

Serum profiling identifies CCL8, CXCL13, and IL-1RA as markers of active disease in patients with systemic lupus erythematosus

Introduction

Systemic lupus erythematosus (SLE) is a clinically heterogeneous disease that presents a challenge for clinicians. To identify potential biomarkers for diagnosis and disease activity in SLE, we investigated a selected yet broad panel of cytokines and autoantibodies in patients with SLE, healthy controls (HC), and patients with other autoimmune diseases (AIDs).

Methods

Serum samples from 422 SLE patients, 546 HC, and 1223 other AIDs were analysed within the frame of the European PRECISESADS project (NTC02890121). Cytokine levels were determined using Luminex panels, and autoantibodies using different immunoassays.

Results

Of the 83 cytokines analysed, 29 differed significantly between patients with SLE and HC. Specifically, CCL8, CXCL13, and IL-1RA levels were elevated in patients with active, but not inactive, SLE versus HC, as well as in patients with SLE versus other AIDs. The levels of these cytokines also correlated with SLE Disease Activity Index 2000 (SLEDAI-2K) scores, among five other cytokines. Overall, the occurrence of autoantibodies was similar across SLEDAI-2K organ domains, and the correlations between autoantibodies and activity in different organ domains were weak.

Discussion

Our findings suggest that, upon validation, CCL8, CXCL13, and IL-1RA could serve as promising serum biomarkers of activity in SLE.

A Network Pharmacology and Molecular Docking Strategy to Explore Potential Targets and Mechanisms Underlying the Effect of Curcumin on Osteonecrosis of the Femoral Head in Systemic Lupus Erythematosus

Background

Systemic lupus erythematosus (SLE) is a refractory immune disease, which is often complicated with osteonecrosis of the femoral head (ONFH). Curcumin, the most active ingredient of Curcuma longa with a variety of biological activities, has wide effects on the body system. The study is aimed at exploring the potential therapeutic targets underlying the effect of curcumin on SLE-ONFH by utilizing a network pharmacology approach and molecular docking strategy.

Methods

Curcumin and its drug targets were identified using network analysis. First, the Swiss target prediction, GeneCards, and OMIM databases were mined for information relevant to the prediction of curcumin targets and SLE-ONFH-related targets. Second, the curcumin target gene, SLE-ONFH shared gene, and curcumin-SLE-ONFH target gene networks were created in Cytoscape software followed by collecting the candidate targets of each component by R software. Third, the targets and enriched pathways were examined by Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis. Eventually, a gene-pathway network was constructed and visualized by Cytoscape software; key potential central targets were verified and checked by molecular docking and literature review.

Results

201 potential targets of curcumin and 170 related targets involved in SLE-ONFH were subjected to network analysis, and the 36 intersection targets indicated the potential targets of curcumin for the treatment of SLE-ONFH. Additionally, for getting more comprehensive and accurate candidate genes, the 36 potential targets were determined to be analyzed by network topology and 285 candidate genes were obtained finally. The top 20 biological processes, cellular components, and molecular functions were identified, when corrected by a P value ≤ 0.05. 20 related signaling pathways were identified by KEGG analysis, when corrected according to a Bonferroni P value ≤ 0.05. Molecular docking showed that the top three genes (TP53, IL6, VEGFA) have good binding force with curcumin; combined with literature review, some other genes such as TNF, CCND1, CASP3, and MMP9 were also identified.

Conclusion

The present study explored the potential targets and signaling pathways of curcumin against SLE-ONFH, which could provide a better understanding of its effects in terms of regulating cell cycle, angiogenesis, immunosuppression, inflammation, and bone destruction.

Association between interleukin-1 alpha rs1800587 polymorphism and rheumatoid arthritis: A meta-analysis

No consistent results have been reached on the relationship of interleukin-1 (IL-1) rs1800587 polymorphism with the susceptibility to rheumatoid arthritis (RA) so far. Therefore, the current meta-analysis was designed to thoroughly review relevant studies, in order to examine the relationship of IL-1A rs1800587 polymorphism with RA risk. Electronic databases were retrieved for literature regarding the relationship between IL-1A rs1800587 polymorphism and RA vulnerability according to the inclusion and exclusion criteria. Stata 12.0 software was adopted to examine the enrolled literature. Meanwhile, odds ratio (OR) and corresponding 95% confidence intervals (95% CI) were used to evaluate the association. A total of seven case-control researches (3267 patients and 2960 healthy controls) were eventually enrolled into the current meta-analysis. Our data indicated no correlation of IL-1A rs1800587 polymorphism with RA risk (TT vs CC: OR = 0.90, 95% CI = 0.73-1.11; TC vs CC: OR = 1.02, 95% CI = 0.78-1.34; Dominant model: OR = 1.04, 95% CI = 0.80-1.35; Recessive model: OR = 1.91, 95% CI = 0.74-1.12). Similarly, no association was found in subgroup analysis stratified by ethnicity. Our findings indicated no relationship between IL-1A rs1800587 polymorphism and RA vulnerability.

The IL-1 family cytokines and receptors in autoimmune diseases

The role of the cytokines and receptors of the IL-1 family in inflammation is well known. Several cytokines of the family have a powerful inflammatory activity, with IL-1β being the best-characterized factor. The inflammatory activity of IL-1 cytokines is regulated by other factors of the family, including receptor antagonists, soluble receptors and anti-inflammatory cytokines. The causative role of IL-1β is well-established in autoinflammatory diseases, mainly due to gain-of-function mutations in genes encoding the IL-1β-maturing inflammasome. Exaggerated production of IL-1β and IL-18 correlates with disease and disease severity also in several autoimmune and chronic inflammatory and degenerative pathologies, although it is not clear whether they have a causative role or are only involved in the downstream disease symptoms. A better understanding of the pathological role of IL-1 family cytokines in autoimmunity involves a deeper evaluation, in the pathological situations, of the possible anomalies in the feed-back anti-inflammatory mechanisms that in physiological reactions control and dump IL-1-mediated inflammation. Thus, we expect that IL-1 cytokines may be pathogenic only when, in addition to enhanced production, there is a concomitant failure of their control mechanisms. In this review we will examine the current knowledge on the role of IL-1 family cytokines in autoimmune and chronic inflammatory and degenerative diseases, with a particular focus on their endogenous control mechanisms, mainly based on soluble receptors/inhibitors and receptor antagonists. This will allow us to formulate a knowledge-based hypothesis on the involvement of IL-1 cytokines in the pathogenesis vs. the clinical features of these diseases.

B cell-intrinsic TLR9 expression is protective in murine lupus

Toll-like receptor 9 (TLR9) is a regulator of disease pathogenesis in systemic lupus erythematosus (SLE). Why TLR9 represses disease while TLR7 and MyD88 have the opposite effect remains undefined. To begin to address this question, we created 2 alleles to manipulate TLR9 expression, allowing for either selective deletion or overexpression. We used these to test cell type-specific effects of Tlr9 expression on the regulation of SLE pathogenesis. Notably, Tlr9 deficiency in B cells was sufficient to exacerbate nephritis while extinguishing anti-nucleosome antibodies, whereas Tlr9 deficiency in dendritic cells (DCs), plasmacytoid DCs, and neutrophils had no discernable effect on disease. Thus, B cell-specific Tlr9 deficiency unlinked disease from autoantibody production. Critically, B cell-specific Tlr9 overexpression resulted in ameliorated nephritis, opposite of the effect of deleting Tlr9. Our findings highlight the nonredundant role of B cell-expressed TLR9 in regulating lupus and suggest therapeutic potential in modulating and perhaps even enhancing TLR9 signals in B cells.

Anakinra for Recurrent Fevers in Systemic Lupus Erythematosus

Fever is a common manifestation in systemic lupus erythematosus (SLE) and may be associated with disease activity, but should be closely evaluated for infection, drug reaction, thromboembolism, malignancy, or other etiology. We present the case of a 44-year-old Peruvian female with SLE with periodic high fevers and elevated high-sensitivity C-reactive protein (hs-CRP) levels, treated with anakinra, an interleukin-1 (IL-1) inhibitor. Following the birth of her first child, she developed frequent episodic fevers followed by multiple hospitalizations, approximately two to three times per year. She was started on anakinra in September 2016 and had improvement of fevers and joint symptoms. On 26-month follow-up, she had one episode of fever with bandemia requiring hospitalization but otherwise remained afebrile with a significant drop in CRP. Anakinra is well-tolerable and safe due to a short half-life. We report that the inhibition of IL-1 may be a safe and effective treatment for recurrent fevers in SLE.

Meta-analyses of IL1A polymorphisms and the risk of several autoimmune diseases published in databases

Background

Based on published data, we aimed to quantitatively elucidate the possible genetic influence of rs17561 G/T and rs1800587 C/T polymorphisms of the IL1A (interleukin 1 alpha) gene in the susceptibility to several autoimmune diseases.

Methods

A series of meta-analyses were carried out. After database searching, we utilized our inclusion/exclusion criteria to screen and include the eligible studies. P_association (P value of association test), Bonferroni-corrected P_association value; false discovery rate (FDR)-corrected P_association, ORs (odd ratios), and 95% CI (confidence interval) were generated to assess the magnitudes of genetic relationships.

Results

A total of 35 eligible articles were included. Pooled analysis data of both rs17561 G/T and rs1800587 C/T in the overall population indicated a negative association between cases of autoimmune diseases and negative controls (all P_association>0.05, Bonferroni-corrected P_association>0.05, FDR-corrected P_association>0.05). Similar results were found in most subgroup analyses (all P_association>0.05, Bonferroni-corrected P_association>0.05, FDR-corrected P_association>0.05), apart from the rs1800587 in the Graves’ disease subgroup, which showed an increased risk in some cases, compared with controls, under the models of allele T vs. C, carrier T vs. C, CT+TT vs. CC, and CT vs. CC (all P_association<0.05, Bonferroni-corrected P_association<0.05, FDR-corrected P_association>0.05, OR>1).

Conclusion

Based on the available data, C/T genotype of the rs1800587 polymorphism within IL1A gene may be associated with an increased Graves’ disease risk. We did not see evidence regarding a positive role for rs1800587 or rs17561 in the risk of other autoimmune diseases, such as systemic sclerosis or rheumatoid arthritis. These conclusions still merit further data support and molecular exploration.

Autoantibody-Positive Healthy Individuals Display Unique Immune Profiles That May Regulate Autoimmunity

Objective

Antinuclear antibodies (ANAs) are detected in ∼18% of females, yet autoimmune disease develops in only 5–8%. Immunologic differences between ANA‐positive healthy individuals and patients with systemic lupus erythematosus (SLE) may elucidate the regulatory mechanisms by which ANA‐positive individuals avoid transition to clinical autoimmune disease.

Methods

Healthy individuals (n = 790) were screened for autoantibodies specific for 11 antigens associated with lupus, systemic sclerosis, and Sjögren's syndrome. From this screening, 31 European American ANA‐positive healthy individuals were selected and demographically matched to ANA‐negative controls and SLE patients. Serum cytokine profiles, leukocyte subset frequency, and reactivity were analyzed by multiplex assays, immunophenotyping, and phosphospecific flow cytometry.

Results

Of 790 individuals screened, 57 (7%) were ANA‐positive. The majority of proinflammatory cytokines, including interferon‐γ (IFNγ), tumor necrosis factor, interleukin‐17 (IL‐17), and granulocyte colony‐stimulating factor, exhibited a stepwise increase in serum levels from ANA‐negative controls to ANA‐positive healthy individuals to SLE patients (P < 0.0001). IFNα, IFNβ, IL‐12p40, and stem cell factor/c‐Kit ligand were increased in SLE patients only (P < 0.05). B lymphocyte stimulator (BlyS) was elevated in SLE patients but decreased in ANA‐positive individuals (P < 0.001). Further, IL‐1 receptor antagonist (IL‐1Ra) was down‐regulated in SLE patients only (P < 0.0001). ANA‐positive individuals had increased frequencies of monocytes, memory B cells, and plasmablasts and increased levels of pSTAT‐1 and pSTAT‐3 following IFNα stimulation compared with ANA‐negative controls (P < 0.05).

Conclusion

ANA‐positive healthy individuals exhibit dysregulation in multiple immune pathways yet differ from SLE patients by the absence of elevated IFNs, BLyS, IL‐12p40, and stem cell factor/c‐Kit ligand. Further, severely decreased levels of IL‐1Ra in SLE patients compared with ANA‐positive individuals may contribute to disease development. These results highlight the importance of IFN‐related pathways and regulatory elements in SLE pathogenesis.

Interleukin-1β (IL-1β) & IL-4 gene polymorphisms in patients with systemic lupus erythematosus (SLE) & their association with susceptibility to SLE

Background & objectives:

Interleukin-1 (IL-1) is one of the pro-inflammatory cytokines that plays a main role in the regulation of immune and inflammatory responses. Interleukin 4 (IL-4) as an anti-inflammatory cytokine regulates balance between Th1 and Th2 immune responses. This study was undertaken to investigate the IL-1β and IL-4 genes polymorphisms in patients with systemic lupus erythematosus (SLE) and also association between the polymorphisms and susceptibility to SLE.

Methods:

One hundred and sixty three SLE patients and 180 healthy controls were genotyped for the IL-4 VNTR (variable number tandem repeat), IL-1β C-511T and IL-1β T-31C polymorphisms by polymerase chain reaction (PCR) or PCR-RFLP (restriction fragment length polymorphism) method.

Results:

The frequencies of CC genotype and C allele of the IL-1β T-31C polymorphism were significantly (P<0.01) lower in SLE patients than controls. Moreover, the frequencies of RP1/RP2 genotype and RP2 allele of IL-4 VNTR polymorphism were significantly (P<0.05) higher in the SLE patients. No association was observed between IL-1β C-511T polymorphism and increased risk of SLE. We observed increased frequency of CT and TT genotypes of IL-1β C-511T polymorphism in SLE patients with malar rash compared to SLE patients without this manifestation.

Interpretation & conclusions:

The present findings suggest that IL-1β T-31C and IL-4 VNTR polymorphisms but not IL-1β C-511T polymorphism may contribute in SLE pathogenesis. In addition, CT and TT genotypes of IL-1β C-511T polymorphism were associated with SLE.

The innate immune system in human systemic lupus erythematosus

Although the role of adaptive immune mechanisms, e.g. autoantibody formation and abnormal T-cell activation, has been long noted in the pathogenesis of human systemic lupus erythematosus (SLE), the role of innate immunity has been less well characterized. An intricate interplay between both innate and adaptive immune elements exists in protective anti-infective immunity as well as in detrimental autoimmunity. More recently, it has become clear that the innate immune system in this regard not only starts inflammation cascades in SLE leading to disease flares, but also continues to fuel adaptive immune responses throughout the course of the disease. This is why targeting the innate immune system offers an additional means of treating SLE. First trials assessing the efficacy of anti-type I interferon (IFN) therapy or modulators of pattern recognition receptor (PRR) signalling have been attempted. In this review, we summarize the available evidence on the role of several distinct innate immune elements, especially neutrophils and dendritic cells as well as the IFN system, as well as specific innate PRRs along with their signalling pathways. Finally, we highlight recent clinical trials in SLE addressing one or more of the aforementioned components of the innate immune system.

Anti-inflammatory panacea? The expanding therapeutics of interleukin-1 blockade

PURPOSE OF REVIEW

Blockade of interleukin (IL)-1 signaling is one of the oldest biologic therapies, yet the use of these agents is on the rise as the role of IL-1 activation is being recognized in a wide spectrum of inflammatory disorders. This review will cover established and emerging uses of IL-1 antagonism in rheumatic diseases.

RECENT FINDINGS

Expanding off-label indications for IL-1 blockade include neutrophil-dominant skin diseases, including pyoderma gangrenosum, hidradenitis supperativa, and pustular psoriasis. There is also increasing evidence for the use of IL-1 blockade in heart failure associated with rheumatic diseases. Somatic mosaicism in NLRP3 may explain the onset of later-in-life presentations of periodic fevers which are responsive to IL-1 blockade. Of importance, clinical response to anti-IL-1 therapy does not always denote protection from autoinflammatory disease complications such as macrophage activation syndrome or amyloidosis.

SUMMARY

Indications for IL-1 blocking therapies will likely continue to broaden, but given the rarity of many rheumatic diseases which respond to such treatment, rigorous, large clinical trials for each indication are unlikely to occur. Thus, recommended use of these medications will often fall to the discretion of the astute physician. However, medication cost and hurdles of insurance approval, rather than drug efficacy, may be the primary limitation for more widespread use.

The murine Pbx1-d lupus susceptibility allele accelerates mesenchymal stem cell differentiation and impairs their immunosuppressive function

Pre–B cell leukemia homeobox 1 (Pbx1)-d is a dominant-negative splice isoform of the gene Pbx1 that corresponds to the NZM2410 lupus susceptibility locus Sle1a1. Pbx1 is required to maintain stem cell self-renewal, including that of mesenchymal stem cells (MSCs). MSCs have immunosuppressive functions that require stem cell maintenance. We tested the hypothesis that the expression of Pbx1-d favors MSC differentiation and impairs their immunosuppressive functions. We demonstrate that Sle1a1 MSCs express high levels of Pbx1-d as compared with congenic C57BL/6J (B6) MSCs. Sle1a1 MSCs grew faster and differentiated significantly more rapidly into osteoblasts than did B6 MSCs. This corresponded to a significant decrease in the expression of genes associated with stemness and an increase in the expression of genes associated with differentiation. Additionally, Sle1a1 MSCs express a gene expression profile associated with an enhanced innate immunity and inflammation. Suppression of Ig production from TLR-activated B6 B cells and IL-2 secretion from activated B6 CD4+ T cells was significantly impaired in Sle1a1 MSCs as compared with B6 MSCs. B6.Sle1a1 MSCs showed intermediate activity in suppressing lupus immunophenotypes in three different mouse models. Taken together, these data suggest that the expression of the lupus susceptibility allele Pbx1-d isoform impairs MSC functions, which may contribute to lupus pathogenesis both through a defective immunosuppression and the promotion of a proinflammatory environment.

Genetic Variants That Are Associated with Neuropsychiatric Systemic Lupus Erythematosus

OBJECTIVE

While genetic risks have been implicated in systemic lupus erythematosus (SLE), the involvement of various genotypes in neuropsychiatric SLE (NPSLE) remains uncertain. The present metaanalysis aimed to combine data from different studies and evaluate the association between each genotype and the risk of developing NPSLE.

METHODS

Studies were searched and retrieved from online databases (PubMed, EMBASE, BIOSIS, and ScienceDirect). Case-control studies were chosen if they reported genotype frequencies of the γ Fc region (FCγR) receptors II-A, III-A, and III-B; tumor necrosis factor-α (TNF-α); mannan-binding lectin (MBL); integrin alpha M (ITGAM); interleukin (IL) 1, IL-1β, and IL-6; IL-10 promoter; and vitamin D genes. The OR were used to assess the strength of this association between patients with NPSLE and SLE.

RESULTS

A total of 33 studies were considered in this metaanalysis. The results suggest that these genotypes demonstrated a significant association with NPSLE: the homozygous FCγR IIIa 158 FF genotype (OR 1.89, p = 0.03 for FF vs VV + FV), heterozygous FCγR IIIb NA1/2 genotype (OR 2.14, p = 0.03 for NA1/2 vs NA1/1; OR 1.81, p = 0.04 for NA1/2 vs NA1/1 + NA2/2), and homozygous ITGAM rs1143679 HH genotype (OR 3.39, p = 0.04 for HH vs RH; OR 3.11, p = 0.048 for HH vs RR + RH). Polymorphisms of the TNF-α, MBL2, IL-1, IL-1β, IL-6, IL-10 promoter, and vitamin D receptor genes did not show a statistically significant association with the risk of developing NPSLE (p > 0.05).

CONCLUSION

This metaanalysis indicates that polymorphisms in the pathways of immune complex clearance, such as the FcγRIIIa, FcγRIIIb, and ITGAM genotypes, are potential susceptibility genes for NPSLE.

Association of insulin gene variable number of tandem repeats regulatory polymorphism with polycystic ovary syndrome

The present meta-analysis aimed to investigate the association between insulin gene variable number of tandem repeats (INS VNTR) and polycystic ovary syndrome (PCOS). Systematic searches of electronic databases, reference lists of included articles, and the abstracts presented at related scientific societies meetings were performed. Statistical analyses were conducted using software Stata 11.0. The pooled odds ratios (ORs) with 95% confidence intervals (95% CIs) were applied. Publication bias was tested by Begg's funnel plot and Egger's regression test. A total of 9 studies including 1075 PCOS patients and 2878 controls were included in the meta-analysis. There were evidence of statistical significant association between INS VNTR and PCOS in allelic model (OR=1.25, 95% CI=1.08-1.43, P=0.002) and dominant model (OR=1.34, 95% CI=1.11-1.63, P=0.003) but not in additive model (OR=1.38, 95% CI=0.93-2.04, P=0.11) and recessive model (OR=1.26, 95% CI=0.96-1.65, P=0.09). No significant publication bias was shown by funnel plots and Egger's regression tests. In conclusion, our meta-analysis suggests that the III allele of INS VNTR is associated with increased risk of PCOS.

IL-1RN VNTR Polymorphism in Adult Dermatomyositis and Systemic Lupus Erythematosus

Polymorphisms in the cytokine genes and their natural antagonists are thought to influence the predisposition to dermatomyositis (DM) and systemic lupus erythematosus (SLE). A variable number tandem repeat (VNTR) polymorphism of 86 bp in intron 2 of the interleukin-1 receptor antagonist (IL-1RN) gene leads to the existence of five different alleles which cause differences in the production of both IL-1RA (interleukin-1 receptor antagonist) and IL-1β. The aim of this case-control study was to investigate the association between the IL-1RN VNTR polymorphism and the susceptibility to DM and SLE in Bulgarian patients. Altogether 91 patients, 55 with SLE and 36 with DM, as well as 112 unrelated healthy controls, were included in this study. Only three alleles were identified in both patients and controls ((1) four repeats, (2) two repeats, and (3) five repeats). The IL-1RN*2 allele (P = 0.02, OR 2.5, and 95% CI 1.2-5.4) and the 1/2+2/2 genotypes were found prevalent among the SLE patients (P = 0.05, OR 2.6, and 95% CI 1-6.3). No association was found between this polymorphism and the ACR criteria for SLE as well as with the susceptibility to DM. Our results indicate that the IL-1RN VNTR polymorphism might play a role in the susceptibility of SLE but not DM.