Changes of Serum IL-6, IL-17, and Complements in Systemic Lupus Erythematosus Patients

Adenohypophysis-Inducible Sex Hormones Correlate with Interleukin-6, -8, and Tumor Necrosis Factor-α in Patients with Systemic Lupus Erythematosus

Adenohypophysis-inducible sex hormones include prolactin (PRL), follicle-stimulating hormone (FSH), and luteinizing hormone (LH). These hormones influence the occurrence of lupus erythematosus by affecting the endocrine and immune systems. The present study analyzed the relationship between serum sex hormones and several cytokines in patients with systemic lupus erythematosus (SLE). Compared with the healthy controls, early-onset SLE female patients with menopause had higher PRL levels than the healthy controls and cutaneous lupus erythematosus (CLE) group. FSH levels were higher in male patients with SLE than in the healthy controls or CLE group. In SLE patients, the estradiol levels correlated negatively with interleukin (IL)-8. The levels of FSH versus IL-8, PRL versus IL-6, PRL versus tumor necrosis factor (TNF)-α, and LH versus IL-8 levels were moderately positively correlated. In conclusion, PRL, FSH, and LH are positively associated with IL-6, IL-8, and TNF-α in the sera from SLE patients, which indicates that sex hormone levels can serve as an indicator of disease activity during SLE diagnosis.

The reduced frequency of CD39+CD73+ B cell subsets in SLE patients is correlated with disease activity

BACKGROUND

Systemic lupus erythematosus (SLE) is a heterogeneous autoimmune disease characterized by immune mechanisms dysregulation, leading to the production of diverse autoantibodies. However, the immune pathways underlying B-cell function and phenotypic abnormalities related to SLE pathogenesis remain incompletely understood.

OBJECTIVE

To explore new markers of SLE activity and potential targets for SLE immunotherapy.

METHODS

Collect peripheral blood mononuclear cells (PBMCs) from SLE patients and healthy controls (HC). Use flow cytometry to detect CD39 and CD73 expression on B cell subsets and enzyme-linked immunosorbent assay (ELISA) to measure adenosine (ADO) concentrations in SLE patients' serum. Compare CD39+CD73+ B cell subsets frequency and ADO concentrations in SLE patients and HC group. Additionally, analyze the correlation between CD39+CD73+ B cell subsets frequency and clinical laboratory parameters.

RESULTS

CD39 and CD73 are simultaneously highly expressed on CD19+ B cell subsets, with significantly lower frequency of CD39+CD73+ B cell subsets in SLE patients compared to HC group. This frequency negatively correlates with Systemic Lupus Erythematosus Disease Activity Index (SLEDAI), C-reactive protein (CRP), and anti-double-stranded DNA (anti-dsDNA) antibodies, while positively correlating with IgM and prothrombin time (PT). Additionally, the frequency of CD39+CD73+ B cell subsets is significantly negatively correlated with IL-6 and IFN-α. In vitro cell experiments demonstrate that adenosine significantly inhibits R848-induced inflammatory cytokine production in a dose-dependent manner.

CONCLUSION

The frequency of CD39+CD73+ B cell subsets of SLE patients is decreased, correlating with clinical laboratory parameters and disease activity. Simultaneously, ADO concentration in the patients' serum is reduced. The CD39+CD73+ B cell/ADO pathway may represent a novel immunotherapy strategy for SLE.

Psoriasis and Lupus Erythematosus-Similarities and Differences between Two Autoimmune Diseases

Systemic lupus erythematosus (SLE) and psoriasis (Ps) are two clinically distinct diseases with different pathogenesis. However, recent studies indicate some similarities in both clinical presentation and pathogenetic mechanisms. The coexistence of both entities is very uncommon and has not been fully elucidated. Thus, it remains a diagnostic and therapeutic challenge. In fact, drugs used in SLE can induce psoriatic lesions, whereas phototherapy effective in Ps is an important factor provoking skin lesions in patients with SLE. The aim of this work is to discuss in detail the common pathogenetic elements and the therapeutic options effective in both diseases.

New and emerging therapies for systemic lupus erythematosus

Systemic Lupus Erythematosus (SLE) and lupus nephritis treatment is still based on non-specific immune suppression despite the first biological therapy for the disease having been approved more than a decade ago. Intense basic and translational research has uncovered a multitude of pathways that are actively being evaluated as treatment targets in SLE and lupus nephritis, with two new medications receiving FDA approval in the last 3 years. Herein we provide an overview of targeted therapies for SLE including medications targeting the B lymphocyte compartment, intracellular signaling, co-stimulation, and finally the interferons and other cytokines.

Lymphocyte apoptosis and its association with the inflammatory markers and disease severity in juvenile-onset systemic lupus erythematosus patients

BACKGROUND

The defective clearance of apoptotic bodies in juvenile-onset systemic lupus erythematosus (jSLE) potentially leads to the persistence of autoreactive lymphocytes and the perpetuation of the autoimmune response. These factors contribute to the disturbance in lymphocyte apoptosis and show potential as key determinants in the clinical course and severity of jSLE. This study evaluates the role of peripheral blood (PB) lymphocyte apoptosis in prognosis of jSLE and as a predictor for disease activity.

METHODS

The study involved 100 jSLE patients and 50 healthy controls. Flow cytometry was used to analyze percentages of lymphocyte apoptosis in PB of all study participants. Plasma levels of pro-inflammatory cytokines were determined using ELISA.

RESULTS

Our results showed that percentages of lymphocyte apoptosis in PB of jSLE patients are significantly higher than those of healthy controls. These percentages are significantly positively associated with disease activity of patients (SLEDAI-2 K). Furthermore, plasma cytokine levels (IL-17, IFN-γ and TNF-α) are significantly elevated in jSLE patients compared to their levels in healthy controls. Also, there are weak significant positive correlations between percentages of PB lymphocyte apoptosis and each of IL-17 and IFN-γ plasma levels in jSLE patients. Moreover, PB lymphocyte apoptosis percentages among jSLE patients are higher in the presence of some clinical and laboratory features than those in their absence.

CONCLUSION

Peripheral apoptotic lymphocytes could contribute to the prognosis of jSLE and could be used as a predictor for disease activity in jSLE patients.

Chemokines and Cytokines Profiles in Patients with Antineutrophil Cytoplasmic Antibodies-Associated Vasculitis: A Preliminary Study

The damage to small vessels in AAV and inflammatory reactions are accompanied by the release of various chemokines and cytokines. Using a flow cytometry technique, we assessed the levels of specific cytokines, namely IL-1β IL-6, IL-8, IL-10, IL12p70, and TNF, and chemokines, IFN-α, IP-10, and MIG in the serum from 9 healthy volunteers and 20 AAV patients, where 11 of the patients were not treated and evaluated at the time of diagnosis and 9 were already diagnosed and taking CY + GCS. The obtained results were then compared considering the activity of the disease, the type and titre of the ANCA antibodies, the inflammatory status, and the kidneys' condition. Amongst others, the IL-6, IL-8, IL-10, TNF, and MIG levels were much higher in the serum of AAV patients than in healthy controls, whereas the level of IL-1β was higher in healthy volunteers. Additionally, the levels of IL-6, IL-10, IP-10, and MIG negatively correlated with the eGFR level, while the level of IFN-α positively correlated with the titre of PR3-ANCA. As most of the molecules are implicated in trafficking primed neutrophils towards small vessels, looking for links between the levels of these cytokines/chemokines and the clinical symptoms of AAV may facilitate the diagnosis and predict the progression of the disease.

Cytokines in Systemic Lupus Erythematosus-Focus on TNF-α and IL-17

Systemic lupus erythematosus (SLE) is an autoimmune disorder known for its complex pathogenesis, in which cytokines play an essential role. It seems that the modulation of these cytokines may impact disease progression, being considered potential biomarkers. Thus, TNF (tumor necrosis factor)-α and IL (interleukin)-17 are molecules of great interest in SLE. TNF-α plays a dual role in SLE, with both immunosuppressive and proinflammatory functions. The role of IL-17 is clearly described in the pathogenesis of SLE, having a close association with IL-23 in stimulating the inflammatory response and consecutive tissue destruction. It appears that patients with elevated levels of these cytokines are associated with high disease activity expressed by the SLE disease activity index (SLEDAI) score, although some studies do not confirm this association. However, TNF-α and IL-17 are found in increased titers in lupus patients compared to the general population. Whether inhibition of these cytokines would lead to effective treatment is under discussion. In the case of anti-TNF-α therapies in SLE, the possibility of ATIL (anti-TNF-induced lupus) is a serious concern that limits their use. The use of anti-IL-17 therapies in SLE is a promising option, but not yet approved. Future studies of these cytokines in large cohorts will provide valuable information for the management of SLE.

Nailfold capillaroscopy in Egyptian systemic lupus erythematosus (SLE) patients: correlation with demographic features and serum levels of IL 17A and IFNs I

Background

In SLE patients, cytokines are linked to endothelial cell damage. Nailfold capillaroscopy (NFC) is a simple method for evaluating micro-vascular abnormalities in different connective tissue diseases (CTDs). The study aimed to detect the levels of interleukin 17A (IL 17A), type I interferons (IFNs I) in the serum, and NFC changes in Egyptian SLE patients compared to a control group and to correlate NFC findings with patients’ demographic features and serum levels of IL 17A and IFNs I.

Results

Serum levels of IL 17A, IFN α, and IFN β were significantly higher in SLE patients than in control group (P < 0.0001). About thirty nine patients (73.6%) of the 53 SLE patients showed abnormal NFC changes. Egyptian SLE patients had a high prevalence of the NFC non-specific pattern, with 32 (60.4%) patients showing non-specific changes and 7 (13.2%) patients showing scleroderma pattern, including 3 (5.6%) patients with active scleroderma pattern and 4 (7.55%) patients with late scleroderma pattern. Furthermore, Raynaud’s phenomenon (RP) was observed in 8 (15.1%) SLE patients, with 3 (5.6%) having normal NFC pattern and 5 (9.4%) having scleroderma pattern. All controls (n = 20) showed normal hairpin shape capillaries. Except for SLEDAI (P = 0.03) and the presence of RP (P < 0.0001), there were no significant differences in demographic and laboratory parameters between the three NFC patterns (normal, non-specific, and scleroderma); additionally, NFC score correlated significantly with SLEDAI (P = 0.021).

Conclusion

As a result of the high disease activity, Egyptian SLE patients had elevated serum levels of IL 17A and IFNs I. The most common NFC pattern in Egyptian SLE patients was a non-specific pattern. NFC abnormalities in Egyptian SLE patients were correlated with disease activity but not with patients’ ages, disease duration, or serum levels of IL 17A and IFNs I. SLE patients with scleroderma NFC pattern and RP should be closely followed for the possibility of appearance of anti-U1 RNP antibodies and MCTDS.

The Association of Complements, TGF-β, and IL-6 with Disease Activity, Renal Damage, and Hematological Activity in Patients with Naïve SLE

Several key player factors, such as cytokine and complement, play an important role in the pathogenesis of systemic lupus erythematosus (SLE). The purpose of this study was to reveal the association between complement 3 (C3), complement 4 (C4), interleukin-6 (IL-6), and transforming growth factor-β (TGF-β) with SLE disease activity, renal damage, and hematological activity in patients with naïve SLE. The Laboratory of Clinical Pathology Dr. Soetomo General Hospital in Surabaya performed all laboratory examinations on thirty women with naïve SLE. The SLE diagnosis is based on ACR criteria (1998 revised criteria) from Dr. Soetomo General Hospital Surabaya, Indonesia, and the systemic lupus activity measurement (SLAM) score is used to assess the disease activity. The correlation was statistically tested using the Spearman and Pearson tests. The differences in cytokine and complement levels are between SLE severity groups using the two-way Anova and Kruskal-Wallis. The unpaired T-test and Mann-Whitney test were used to determine the differences between the relatively normal and the more severe groups of organ damage and hematological activity. All tests were two-tailed, analyzed with GraphPad Prism 9 for windows, and a p value of less than 0.05 was considered statistically significant. This study found a significant decrease in C3 (20.2, 16.4-24.2 mg/dL) and C4 (7, 6-14.3 mg/dL) and an increase in IL-6 (35.60 ± 7.43 mg/dL) and TGF-β (311.1 ± 290.8 mg/dL) in the group of severe patients with SLAM scores >30. Although there is no significant relationship between SLAM and renal impairment or hematologic activity, patients with higher SLAM had a significant decrease in complement; this complement decrease was also significant in patients with higher leukocyte counts. An insignificant increase in cytokines was also observed in patients with higher SLAM. Patients with high serum creatinine levels had a significant increase in TGF-β, whereas those with a faster ESR had a significant increase in IL-6. In conjunction with complements evaluation, assessment of the cytokine profile may become a promising marker for reliable diagnosis and treatment of SLE in the future.

Efficacy and safety of belimumab/low-dose cyclophosphamide therapy in moderate-to-severe systemic lupus erythematosus

Objectives

We have reported previously that Belimumab, a human monoclonal antibody that inhibits B-cell activating factor(BAFF) could be an effective and safe option to treat Neuropsychiatric manifestations of SLE (NPSLE). To avoid inadequate efficacy of Belimumab and significant adverse events of often-used dose of cyclophosphamide (CYC) for SLE, we evaluated the efficacy, safety, and possible immune mechanisms of Belimumab treatment in combination with intermittent low-dose intravenous CYC for moderate-to-severe SLE.

Methods

In this non blinded and parallel-group trial, we collected 82 cases of moderate-to-severe SLE patients, 40 received Belimumab treatment and 42 received conventional treatments as historical controls for 24 weeks. The demographic features, clinical manifestations, and laboratory indicators including peripheral blood lymphocyte subgroups or subsets were compared before and after the treatments.

Results

Compared with the baseline, 6 months post Belimumab group treatment, disease activity score SLEDAI (13.78 to 3.82, P<0.05) and BILAG scores (16.40 to 5.48, P<0.05) were reduced; C3 (0.19 to 1.14, P<0.05) and C4 (0.04 to 0.22, P<0.05) increased; the absolute numbers of B and T cells were the first decreased and then significantly increased, tended to balance. Moreover, Belimumab group treatment significantly reduced the serum levels of IL-6, the ratio of B and T cells, and the proportion of infections and menstrual disorders.

Conclusion

Compared with conventional treatment, Belimumab with low-dose intravenous CYC significantly reduced disease activity scores and maintained the B/T cell balance for SLE patients at 24 weeks. It was more efficacy and safe (adverse events such as infection were significantly lower). It should be the mechanism that Belimumab combined with low-dose intravenous CYC therapy restores the balance of T and B cells, which proposes a potential treatment strategyfor SLE.

Serum cytokines to predict systemic lupus erythematosus clinical and serological activity

We aimed to explore the role of interleukin (IL)-6, interferon-gamma (IFNγ), IL-10, and tumor necrosis factor (TNF) as predictors of systemic lupus erythematosus (SLE) clinical and serological activity, and their correlation with the treatment received. We performed a retrospective analysis of 77 patients with SLE according to the 2012 Systemic Lupus International Collaborative Clinics (SLICC) criteria. The outcomes were serological activity (SA), active disease (AD), complete remission (CR), the low-disease activity state (LDAS), and immunosuppressive treatment. SA was present in 17.1%, AD in 17.3%, CR in 13%, and LDAS in 64.9% of patients. IL-6 values were higher in patients in SA, in AD, in those receiving steroids alone, and in patients without CR or LDAS (p < 0.05). IFNγ was associated with anti-double stranded DNA (dsDNA) antibodies positivity and immunosuppression, whereas IL-10 values were higher in patients with CR (p < 0.05). The IL6-IFN product was able to predict anti-double stranded DNA (anti-dsDNA) antibodies positivity (area under the receiver operating characteristic curve [AUC-ROC] = 0.705, 95% confidence interval [CI] 0.563-0.847), SA (AUC-ROC = 0.720, 95% CI 0.542-0.899), AD (AUC-ROC = 0.701, 95% CI 0.520-0.882), steroid treatment (AUC-ROC = 0.751, 95% CI 0.622-0.879), and the absence of LDAS (AUC-ROC = 0.700, 95% CI 0.558-0.834). The IL6-IFN/IL10 ratio predicted AD (AUC-ROC = 0.742, 955 CI 0.540-0.944), steroid treatment (AUC-ROC = 0.721, 95% CI 0.572-0.870), and the absence of LDAS (AUC-ROC = 0.694, 95% CI 0.536-0.853). In conclusion, IL-6, IL-10, and IFNγ might help to assess SLE serological and clinical activity. Their combination in the IL-6-IFN product and the IL-6xIFN to IL-10 ratio results in novel tools to determine and predict SA, AD, and LDAS. Prompt detection of SLE activity might allow a rapid intervention to avoid established or chronic damage.

Systemic lupus erythematous after Pfizer COVID-19 vaccine: a case report

The Pfizer-BioNTech COVID-19 vaccine has been authorized by the U.S. Food and Drug Administration as it demonstrated 95% effectiveness against the SARS-CoV-2 virus. Although the initial vaccine trials showed a favorable side effect profile, there have been concerns regarding activation of aberrant immune responses, triggering autoimmunity. This is a case report of a 68-year-old woman without history of autoimmune conditions, who presented to our emergency department 7 days after receiving the Pfizer-BioNTech COVID-19 vaccine. Her initial symptoms were suggestive of polymyalgia rheumatica, and she had nearly complete response to steroids. Interestingly, she later met criteria for classified systemic lupus erythematous given the development of inflammatory arthritis, positive ANA, and positive dsDNA. The temporal relationship of her symptoms that started 2 days after vaccine administration could suggest a possible association between the Pfizer-BioNTech COVID-19 and the development of systemic lupus erythematous.

Targeting Regulatory T Cells for Therapy of Lupus Nephritis

Lupus glomerulonephritis (LN) is a complex autoimmune disease characterized by circulating autoantibodies, immune-complex deposition, immune dysregulation and defects in regulatory T cell (Tregs). Treatment options rely on general immunosuppressants and steroids that have serious side effects. Approaches to target immune cells, such as B cells in particular, has had limited success and new approaches are being investigated. Defects in Tregs in the setting of autoimmunity is well known and Treg-replacement strategies are currently being explored. The aim of this minireview is to rekindle interest on Treg-targeting strategies. We discuss the existing evidences for Treg-enhancement strategies using key cytokines interleukin (IL)-2, IL-33 and IL-6 that have shown to provide remission in LN. We also discuss strategies for indirect Treg-modulation for protection from LN.

Investigating the Molecular Mechanism of Xijiao Dihuang Decoction for the Treatment of SLE Based on Network Pharmacology and Molecular Docking Analysis

Objective

To elucidate the main mechanism of Xijiao Dihuang decoction (XJDHT) for the treatment of systemic lupus erythematosus (SLE).

Methods

TCMSP, BATMAN-TCM, ETCM, and TCMID databases and literature search were used to screen the potential active compounds of XJDHT, and TCMSP and SwissProt databases were searched to predict the targets of the compounds. The targets of SLE were obtained from Genegards, OMIM, and DisGeNET databases, and Venn online platform was used to obtain the intersection targets of XJDHT and SLE. Afterwards, the PPI network was constructed by using the STRING database, and the core targets were identified by network topology analysis. GO and KEGG enrichment analyses were performed through R software, and molecular docking of the top three core targets and their corresponding compounds were accomplished by Autodock Vina and Pymol softwares.

Results

There were 30 potential active ingredients, 289 potential targets, and 129 intersection targets screened from the above databases. Network topology analysis identified 23 core targets, such as AKT1, TNF, IL6, IL1B, and INS. GO enrichment analysis obtained 2555 terms and mainly clustering on the react to lipopolysaccharide, membrane raft, and ubiquitin-like protein ligase binding. KEGG enrichment analysis obtained 187 signaling pathways, mainly concentrating on the lipid and atherosclerosis, AGE-RAGE signaling pathway in diabetic complications, fluid shear stress, and atherosclerosis. Molecular docking verified that the active compounds of XJDHT have the strong binding activity to the core targets.

Conclusion

This study preliminarily uncovers the mechanism of XJDHT acting on SLE through a “multicompound, multitarget, and multipathway” manner. XJDHT may achieve the treatment of SLE by inhibiting the proinflammatory factors, inflammatory signal cvtokines, proliferation, injury, and apoptosis processes. In summary, the present study would provide a promising theoretical basis for further clinical and experimental studies.

Circulating IL-17 Level Is Positively Associated with Disease Activity in Patients with Systemic Lupus Erythematosus: A Systematic Review and Meta-Analysis

Previous studies on the relationship between the circulating level of interleukin-17 (IL-17) and disease activity in systemic lupus erythematosus (SLE) were contradictory. This study is aimed at quantitatively assessing the correlation between the circulating IL-17 level and disease activity in SLE patients. A systematic search for related literature was conducted via PubMed, Web of Science, EMBASE, and Cochrane Library (up to January 26, 2021). The relationship between circulating IL-17 levels and SLE activity was evaluated using Fisher's z value, which was then converted to r. The standardized mean difference (SMD) and its 95% confidence interval (CI) were used to describe the difference between the circulating IL-17 level in patients with active and inactive SLE. STATA 16.0 was used to perform statistical analysis. Random-effects model was performed to synthesize data. Twenty-six studies involving 1,560 SLE patients were included in this review. The pooled r value was 0.38 (95% CI: 0.25-0.50; I² = 83.8%, P < 0.001) between the SLE activity and circulating level of IL-17. Patients with active SLE had higher level of circulating IL-17 than that of inactive (pooled SMD = 0.95, 95% CI: 0.38-1.53; I² = 90.5%, P < 0.001). The subgroup analysis suggested that the region and detection method of circulating IL-17 might not be a source of heterogeneity. No significant publication bias was found. In summary, circulating IL-17 level has a low positive relationship with SLE activity. It is necessary to carefully consider the use of circulating IL-17 as a biomarker of the disease activity in SLE patients. The relationship between the circulating level of IL-17 and SLE activity should be further confirmed in randomized controlled studies.

Hsa_circ_0010957 level is increased and sponges microRNA‑125b in CD4+ T cells of patients with systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is a severe autoimmune disorder, the pathogenesis of which remains largely unknown. The present study aimed to investigate the role and mechanism of circular RNAs in the etiopathogenesis of SLE. CD4⁺ T cells in patients with SLE expressed higher levels of hsa_circ_0010957 compared with healthy individuals and was a good differentiator of the active from inactive SLE disease. It was also determined that hsa_circ_0010957 mediated microRNA (miR)-125b/STAT3 signaling and subsequent secretion of inflammatory cytokines interleukin (IL)-18, IL-6 and IL-17, which are important factors in the process of SLE. Hsa_circ_0010957 abrogated the proinflammatory effect of IL-6 via the blockade of STAT3 signaling. In conclusion, increased hsa_circ_0010957 may be involved in SLE pathogenesis via miR-125b/STAT3 signaling. Hsa_circ_0010957 promises to be a potential biomarker and therapeutic target for SLE.

Regulation of Toll-like receptor-mediated inflammatory response by microRNA-152-3p-mediated demethylation of MyD88 in systemic lupus erythematosus

OBJECTIVE

microRNAs (miRNAs) play critical roles in embryogenesis, cell differentiation and the pathogenesis of several human diseases, including systemic lupus erythematosus (SLE). Toll-like receptors (TLRs) are also known to exert crucial functions in the immune response activation occurring in the pathogenesis of autoimmune diseases like SLE. Herein, the current study aimed to explore the potential role of miR-152-3p in TLR-mediated inflammatory response in SLE.

METHODS

We determined the miR-152-3p expression profiles in CD4+ T cells and peripheral blood mononuclear cells (PBMCs) harvested from patients with SLE and healthy controls, and analyzed the correlation between miR-152-3p expression and clinicopathological parameters. CD70 and CD40L expression patterns in CD4+ T cells were assessed by RT-qPCR and flow cytometry. ChIP was adopted to determine the enrichment of DNA methyltransferase 1 (DNMT1) in the promoter region of myeloid differentiation factor 88 (MyD88).

RESULTS

The obtained findings revealed that miR-152-3p was highly-expressed in CD4+ T cells and PBMCs of patients with SLE, and this high expression was associated with facial erythema, joint pain, double-stranded DNA, and IgG antibody. DNMT1 could be enriched in the MyD88 promoter, and miR-152-3p inhibited the methylation of MyD88 by targeting DNMT1. We also found that silencing miR-152-3p inhibited MyD88 expression not only to repress the autoreactivity of CD4+ T cells and but also to restrain their cellular inflammation, which were also validated in vivo.

CONCLUSION

Our study suggests that miR-152-3p promotes TLR-mediated inflammatory response in CD4+ T cells by regulating the DNMT1/MyD88 signaling pathway, which highlights novel anti-inflammatory target for SLE treatment.

Effects of Hericium erinaceus polysaccharide on immunity and apoptosis of the main immune organs in Muscovy duck reovirus-infected ducklings

To investigate the effects of Hericium erinaceus polysaccharide (HEP) on immunity in Muscovy duck reovirus (MDRV)-infected ducklings and explore its mechanism of action, an MDRV contact-infection model was established. Then, we investigated the influence of HEP on morphology of main immune organs in MDRV-infected ducklings by HE staining, while antioxidant capacity (T-AOC, MDA), serum protein levels (TP, ALB, GLO), complement levels (C₃, C₄) and antibody levels (IgA, IgM, IgG) were detected. Apoptotic indexes (apoptosisi rate and FAS-L) were also quantified by TUNEL method and immunohistochemical staining. Meanwhile, FADD and CytC (apoptosis-related genes), were tested by quantitative RT-PCR. Results showed that HEP could reduce the injuries of immune organs caused by MDRV. Additionally, HEP markedly diminished MDA (p < 0.01), while significantly increased T-AOC, TP, ALB, GLO, C₃, C₄, IgA, IgM and IgG (p < 0.01 or p < 0.05). Then, HEP shifted apoptosis time to an early MDRV-infected stage and reduced apoptosis at later MDRV-infected stage. This was associated with changes of FADD and CytC. Collectively, our data suggested that HEP could reduce the immunesuppression by many ways, such as decreasing organs' injuries, improving antioxidant capacity, serum proteins levels, antibody levels and complement levels, while diminish the apoptosis by lowering the FADD and CytC.

A Comprehensive Review of Biological Agents for Lupus: Beyond Single Target

Systemic lupus erythematosus (SLE) is an autoimmune disease that involves multiple immune cells. Due to its complex pathogenesis, the effectiveness of traditional treatment methods is limited. Many patients have developed resistance to conventional treatment or are not sensitive to steroid and immunosuppressant therapy, and so emerging therapeutic antibodies have become an alternative and have been shown to work well in many patients with moderate and severe SLE. This review summarizes the biological agents that are in the preclinical and clinical trial study of SLE. In addition to the various monoclonal antibodies that have been studied for a long time, such as belimumab and rituximab, we focused on another treatment for SLE, bispecific antibodies (BsAbs) such as tibulizumab, which simultaneously targets multiple pathogenic cytokines or pathways. Although the application of BsAbs in cancer has been intensively studied, their application in autoimmune diseases is still in the infant stage. This unique combined mechanism of action may provide a novel therapeutic strategy for SLE.

IgG4 Autoantibodies Attenuate Systemic Lupus Erythematosus Progression by Suppressing Complement Consumption and Inflammatory Cytokine Production

Pathogenic autoantibodies can cause inflammation and tissue injury in systemic lupus erythematosus (SLE). Although IgG4 is considered non-inflammatory owing to the unique structure of its hinge region, the role of IgG4 autoantibodies in SLE remains largely unknown. The titers of serum anti-nuclear-IgG antibodies (ANA-IgG) and anti-nuclear-IgG4 antibodies (ANA-IgG4) in newly diagnosed SLE patients were detected. The effects of IgG4 purified from SLE patients (SLE IgG4) and healthy controls on complement consumption and inflammatory cytokine production were evaluated in vitro. The therapeutic effects of mouse IgG1 (functionally resembles human IgG4) purified from lupus-prone MRL-lpr/lpr mice (lupus IgG1) and control mice on disease progression were examined in MRL-lpr/lpr mice. The results showed that SLE patients with equal titers of total serum ANA-IgG (1:3,200) were divided into group I with lower ANA-IgG4 titers (≤ 1:10) and group II with higher ANA-IgG4 titers (≥ 1:100), and disease activity, inflammatory cytokine production, complement consumption, and renal-function parameters in group I SLE patients were more severe than those in group II. Further, compared with control IgG4, SLE IgG4 inhibited complement consumption by autoantibody-autoantigen immune complexes, and also inhibited inflammatory cytokines production by SLE PBMCs in vitro. Moreover, compared with control IgG1, lupus IgG1 exhibited a therapeutic effect on lupus by attenuating disease progression in MRL-lpr/lpr mice. These findings, for the first time, suggest that IgG4 autoantibodies can attenuate SLE progression by suppressing complement consumption and inflammatory cytokine production. Hence, this study may provide novel therapeutic strategies against SLE and other autoimmune diseases.

The regulation and pharmacological modulation of immune complex induced type III IFN production by plasmacytoid dendritic cells

OBJECTIVE

Patients with systemic lupus erythematosus (SLE) have an ongoing interferon (IFN) production due to an activation of plasmacytoid dendritic cells (pDCs), which can be triggered to type I IFN synthesis by RNA containing immune complexes (RNA-IC). Considering emerging data suggesting a role of type III IFN in the SLE disease process, we asked if RNA-IC can induce type III IFN production in pDC and how this production can be regulated.

METHODS

Peripheral blood mononuclear cells (PBMCs) or immune cell subsets were isolated from healthy blood donors or SLE patients and stimulated with IC containing U1 snRNP and SLE-IgG (RNA-IC). Hydroxychloroquine (HCQ) and an interleukin receptor 1-associated kinase 4 inhibitor (IRAK4i) were added to cell cultures. Cytokine mRNA levels were determined with a microarray and protein levels with immunoassays. Single-cell RNA sequencing of pDCs using ddSEQ technology was performed.

RESULTS

Type III IFN mRNA and protein was induced in RNA-IC-stimulated pDC-NK and pDC-B cell co-cultures. A subset of activated pDCs (3%) expressed both type III and type I IFN mRNA. IFN-λ2, IFN-α2b, interleukin (IL)-3, IL-6, or granulocyte-macrophage colony-stimulating factor (GM-CSF) enhanced IFN-λ1/3 production 2-5-fold. HCQ and an IRAK4i blocked the RNA-IC-triggered IFN-λ1/3 production (p < 0.01). IFN-α2b and GM-CSF increased the proportion of SLE patients producing IFN-λ1/3 in response to RNA-IC from 11 to 33%.

CONCLUSIONS

Type III IFN production is triggered by RNA-IC in pDCs in a TLR-MyD88-dependent manner, enhanced by NK and B cells as well as several pro-inflammatory cytokines. These results support a contributing role for both type I and type III IFNs in SLE, which needs to be considered when targeting the IFN system in this disease.

Serum interleukin-6 level is correlated with the disease activity of systemic lupus erythematosus: a meta-analysis

Interleukin-6 (IL-6) plays a crucial role in systemic autoimmunity and pathologic inflammation. Numerous studies have explored serum IL-6 levels in systemic lupus erythematosus (SLE) and their correlation with disease activity. Here, we performed a meta-analysis to quantitatively assess the correlation between the serum IL-6 levels and SLE activity. The PubMed and EMBASE databases were thoroughly searched for relevant studies up to September 2019. Standardized mean differences (SMDs) with 95% confidence intervals (95% CIs) were used to describe the differences between serum IL-6 levels in SLE patients and healthy controls and between those in active SLE patients and inactive SLE patients. The correlation between the serum IL-6 levels and disease activity was evaluated using Fisher's z values. A total of 24 studies involving 1817 SLE patients and 874 healthy controls were included in this meta-analysis. Serum IL-6 levels were significantly higher in SLE patients than in the healthy controls (pooled SMD: 2.12, 95% CI: 1.21-3.03, Active SLE patients had higher serum IL-6 levels than inactive SLE patients (pooled SMD: 2.12, 95% CI: 1.21-3.03). Furthermore, the pooled Fisher's z values (pooled Fisher's z=0.36, 95% CI: 0.26-0.46, p<0.01) showed that there was a positive correlation between the serum IL-6 levels and SLE activity. This study suggested that serum IL-6 levels were higher in patients with SLE than in healthy controls, and they were positively correlated with disease activity when Systemic Lupus Erythematosus Disease Activity Index>4 was defined as active SLE. More homogeneous studies with large sample sizes are warranted to confirm our findings due to several limitations in our meta-analysis.