Type 17 T helper cells-origins, features and possible roles in rheumatic disease

Lipoic acid improves wound healing through its immunomodulatory and anti-inflammatory effects in a diabetic mouse model

Objectives

Diabetes mellitus is a chronic disease that has become more prevalent worldwide because of lifestyle changes. It leads to serious complications, including increased atherosclerosis, protein glycosylation, endothelial dysfunction, and vascular denervation. These complications impair neovascularization and wound healing, resulting in delayed recovery from injuries and an elevated risk of infections. The present study aimed to investigate the effect of lipoic acid (LA) on the key mediators involved in the wound healing process, specifically CD4 + CD25 + T cell subsets, CD4 + CD25 + Foxp3 + regulatory T (Treg) cells, T-helper-17 (Th17) cells that generate IL-17 A, glucocorticoid-induced tumor necrosis factor receptor (GITR) expressing cells, as well as cytokines such as IL-2, IL-1β, IL-6, and TNF-α and IFN-γ. These mediators play crucial roles in epidermal and dermal proliferation, hypertrophy, and cell migration.

Methods

We divided mice into 5 groups: the non-diabetic (normal control; NC), wounded non-diabetic mice (N + W), wounded diabetic mice (D + W), wounded diabetic mice treated with 50 mg/kg lipoic acid (D + W + L50) for 14 days, and wounded diabetic mice treated with 100 mg/kg lipoic acid (D + W + L100) for 14 days.

Results

Flow cytometric analysis indicated that lipoic acid-treated mice exhibited a significant decrease in the frequency of intracellular cytokines (IL-17 A, TNF-α and IFN-γ) in CD4 + T cells, as well as a reduction in the number of GITR-expressing cells. Conversely, a significant upregulation in the number CD4+, CD25+, FOXp3 + and CD4 + CD25 + Foxp3 + regulatory T (Treg) cells was observed in this group compared to both the normal + wounded (N + W) and diabetic + wounded (D + W) groups. Additionally, the mRNA Levels of inflammatory mediators (IL-2, IL-1β, IL-6, and TNF-α) were downregulated in lipoic acid-treated mice compared to other groups. T thereby he histological findings of diabetic skin wounds treated with lipoic acid showed well-healed surgical wounds.

Conclusions

These findings support the beneficial role of lipoic acid in fine-tuning the balance between anti-inflammatory and pro-inflammatory cytokines, influencing both their release and gene expression.

Integrated Analysis Identified TGFBI as a Biomarker of Disease Severity and Prognosis Correlated with Immune Infiltrates in Patients with Sepsis

Background

Sepsis is a major contributor to morbidity and mortality among hospitalized patients. This study aims to identify markers associated with the severity and prognosis of sepsis, providing new approaches for its management and treatment.

Methods

Data were mined from the Gene Expression Omnibus (GEO) databases and were analyzed by multiple statistical methods like the Spearman correlation coefficient, Kaplan-Meier analysis, Cox regression analysis, and functional enrichment analysis. Candidate indicator' associations with immune infiltration and roles in sepsis development were evaluated. Additionally, we employed techniques such as flow cytometry and neutral red staining to evaluate its impact on macrophage functions like polarization and phagocytosis.

Results

Twenty-eight genes were identified as being closely linked to the severity of sepsis, among which transforming growth factor beta induced (TGFBI) emerged as a distinct marker for predicting clinical outcomes. Notably, reductions in TGFBI expression during sepsis correlate with poor prognosis and rapid disease progression. Elevated expression of TGFBI has been observed to mitigate abnormalities in sepsis-related immune cell infiltration that are critical to the pathogenesis and prognosis of the disease, including but not limited to type 17 T helper cells and activated CD8 T cells. Moreover, the protein-protein interaction network revealed the top ten genes that interact with TGFBI, showing significant involvement in the regulation of the actin cytoskeleton, extracellular matrix-receptor interactions, and phagosomes. These are pivotal elements in the formation of phagocytic cups by macrophages, squaring the findings of the Human Protein Atlas. Additionally, we discovered that TGFBI expression was significantly higher in M2-like macrophages, and its upregulation was found to inhibit lipopolysaccharide-induced polarization and phagocytosis in M1-like macrophages, thereby playing a role in preventing the onset of inflammation.

Conclusion

TGFBI warrants additional exploration as a promising biomarker for assessing illness severity and prognosis in patients with sepsis, considering its significant association with immunological and inflammatory responses in this condition.

Identification and Analysis of DNA Methylation Inflammation-Related Key Genes in Intracerebral Hemorrhage

Inflammation and DNA methylation have been reported to play key roles in intracerebral hemorrhage (ICH). This study aimed to investigate new diagnostic biomarkers associated with inflammation and DNA methylation using a comprehensive bioinformatics approaches. GSE179759 and GSE125512 were collected from the Gene Expression Omnibus database, and 3222 inflammation-related genes (IFRGs) were downloaded from the Molecular Signatures Database. Key differentially expressed methylation-regulated and inflammation-related genes (DE-MIRGs) were identified by overlapping methylation-regulated differentially expressed genes (MeDEGs) between patients with ICH and control samples, module genes from weighted correlation network analysis, and IFRGs. Functional annotation of DE-MIRGs was performed using Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG). A protein-protein interaction (PPI) network was constructed to clarify the interrelationships between different DE-MIRGs. The key genes were categorized by least absolute shrinkage selection operator (LASSO) and support vector machine-recursive feature elimination (SVM-RFE), and gene set enrichment analysis (GSEA). A total of 22 DE-MIRGs were acquired from 451 MeDEGs, 3222 IFRGs, and 302 module genes, and were mainly enriched in the GO terms of wound healing, blood coagulation, and hemostasis; and the KEGG pathways of PI3K/Akt signaling, focal adhesion, and regulation of actin cytoskeleton. A PPI network with 22 nodes and 87 edges was constructed based on the 22 DE-MIRGs, 11 of which were selected for key gene selection. Two 2 key genes (SELP and S100A4) were identified using LASSO and SVM-RFE. Finally, SELP was mainly enriched in cell morphogenesis involved in differentiation, cytoplasmic translation, and actin binding of GO terms, and the KEGG pathway including endocytosis, focal adhesion, and platelet activation. S100A4 was mainly enriched in GO terms including mitochondrial inner membrane; mitochondrial respirasome and lysosomal membrane; and the KEGG pathway of oxidative phosphorylation, regulation of actin cytoskeleton, and chemical carcinogenesis-reactive oxygen species. Twenty-two DE-MIRGs-associated inflammation and DNA methylation were identified between patients with ICH and normal controls, and two key genes (SELP and S100A4) were identified and regarded as biomarkers for ICH, which could provide the research foundation for further investigation of the pathological mechanism of ICH.

Age-related bone diseases: Role of inflammaging

Bone aging is characterized by an imbalance in the physiological and pathological processes of osteogenesis, osteoclastogenesis, adipogenesis, and chondrogenesis, resulting in exacerbated bone loss and the development of age-related bone diseases, including osteoporosis, osteoarthritis, rheumatoid arthritis, and periodontitis. Inflammaging, a novel concept in the field of aging research, pertains to the persistent and gradual escalation of pro-inflammatory reactions during the aging process. This phenomenon is distinguished by its low intensity, systemic nature, absence of symptoms, and potential for management. The mechanisms by which inflammaging contribute to age-related chronic diseases, particularly in the context of age-related bone diseases, remain unclear. The precise manner in which systemic inflammation induces bone aging and consequently contributes to the development of age-related bone diseases has yet to be fully elucidated. This article primarily examines the mechanisms underlying inflammaging and its association with age-related bone diseases, to elucidate the potential mechanisms of inflammaging in age-related bone diseases and offer insights for developing preventive and therapeutic strategies for such conditions.

The roles of immune cells in Behçet's disease

Behçet's disease (BD) is a systemic vasculitis that can affect multiple systems, including the skin, mucous membranes, joints, eyes, gastrointestinal and nervous. However, the pathogenesis of BD remains unclear, and it is believed that immune-inflammatory reactions play a crucial role in its development. Immune cells are a critical component of this process and contribute to the onset and progression of BD. By regulating the function of these immune cells, effective control over the occurrence and development of BD can be achieved, particularly with regards to monocyte activation and aggregation, macrophage differentiation and polarization, as well as T cell subset differentiation. This review provides a brief overview of immune cells and their role in regulating BD progression, which may serve as a theoretical foundation for preventing and treating this disease.

T-cell immunoglobulin and mucin-domain containing-3 (TIM-3): Solving a key puzzle in autoimmune diseases

Dysfunctional immune cells participate in the pathogenesis of a variety of autoimmune diseases, although the specific mechanisms remain elusive and effective clinical interventions are lacking. Recent research on immune checkpoint molecules has revealed significant expression of T cell immunoglobulin and mucin domain-containing protein 3 (TIM-3) on the surfaces of various immune cells. These include different subsets of T cells, macrophages, dendritic cells, natural killer cells, and mast cells. Further investigation into its protein structure, ligands, and intracellular signaling pathway activation mechanisms has found that TIM-3, by binding with different ligands, is involved in the regulation of crucial biological processes such as proliferation, apoptosis, phenotypic transformation, effector protein synthesis, and cellular interactions of various immune cells. The TIM-3-ligand axis plays a pivotal role in the pathogenesis of numerous conditions, including autoimmune diseases, infections, cancers, transplant rejection, and chronic inflammation. This article primarily focuses on the research findings of TIM-3 in the field of autoimmune diseases, with a special emphasis on the structure and signaling pathways of TIM-3, its types of ligands, and the potential mechanisms implicated in systemic lupus erythematosus, multiple sclerosis, rheumatoid arthritis, as well as other autoimmune diseases and chronic inflammation. The latest research results in the field of immunology suggest that TIM-3 dysfunction affects various immune cells and participates in the pathogenesis of diseases. Monitoring the activity of its receptor-ligand axis can serve as a novel biological marker for disease clinical diagnosis and prognosis evaluation. More importantly, the TIM-3-ligand axis and the downstream signaling pathway molecules may become key targets for targeted intervention treatment of autoimmune-related diseases.

Association of rheumatoid arthritis with bronchial asthma and asthma-related comorbidities: A population-based national surveillance study

Background

The aim of this study was to investigate the impact of rheumatoid arthritis (RA) on the prevalence of bronchial asthma and asthma-related comorbidities. We also aimed to identify the influence of RA on interrelationship between asthma and asthma-related comorbidities.

Methods

From the Korean National Health and Nutrition Examination Survey, participants >40 years of age who completed questionnaires and spirometry tests were enrolled. Patient data on RA, asthma, allergic rhinitis, atopic dermatitis, chronic obstructive pulmonary disease (COPD), sinusitis, otitis media, and body mass index (BMI) were collected. Logistic regression and network analyses were performed.

Results

A total of 14,272 subjects were enrolled, among which, 334 (2.4%) had RA. RA was significantly associated with asthma (OR 2.32; 95% CI 1.51–3.57), allergic rhinitis (OR 1.51; 95% CI 1.08–2.10), and sinusitis (OR 1.64; 95% CI 1.08–2.50). The network analysis of total patients revealed a positive interrelationship between asthma and allergic rhinitis, sinusitis, otitis media, atopic dermatitis, BMI, and RA. The interrelationship between asthma and sinusitis was stronger in the RA group. Of note, the relationship between asthma and BMI was distinctively found only in the RA group (r = 0.214, P < 0.05). In patients with asthma, the prevalence of obesity was 64% in the presence of RA, and 40% in the absence of RA (P = 0.034).

Conclusion

This study supports the positive association of RA with asthma, allergic rhinitis, and sinusitis. Our analysis suggests a notable interrelationship between the presence of asthma and higher BMI values in patients with RA, indicating that asthma is more obesity-related in patients with RA.

MicroRNA-10b promotes arthritis development by disrupting CD4+ T cell subtypes

Rheumatoid arthritis (RA) is an inflammation-involved disorder and features the disruption of CD4⁺ T lymphocytes. Herein, we describe that microRNA-10b-5p (miR-10b) promotes RA progression by disrupting the balance between subsets of CD4⁺ T cells. MiR-10b-deficient mice protected against collagen antibody-induced arthritis (CAIA) model. RNA sequencing results indicated that disordered genes in miR-10b^−/− CAIA model are closely associated with CD4⁺ T cells differentiation. Moreover, miR-10b mimics promoted Th1/Th17 and suppressed Th2/Treg cells differentiation, whereas miR-10b inhibitor induced contrary effects. In addition, GATA3 and PTEN was confirmed as two targets of miR-10b, and GATA3 siRNA could increase Th1 and reduce Th2 cells meanwhile PTEN siRNA could increase Th17 and decrease Treg cells. Furthermore, miR-10b inhibitor significantly ameliorated collagen-induced arthritis (CIA) development by attenuating the dysfunctional CD4⁺ T cell subpopulations. The present findings suggest that miR-10b could disrupt the balance of CD4⁺ T subsets, while suppressed miR-10b could attenuate the severity of experimental arthritis, which provided us a novel mechanistic and therapeutic insight into the RA.

Novel combination biologic therapy for recalcitrant psoriasis and psoriatic arthritis in a medically complex patient

For patients who do not achieve adequate disease control on biologic monotherapy, or monotherapy with an oral-systemic agent such as methotrexate, combination biologic therapy may be considered. To the best of our knowledge, we report the first case assessing the safety and efficacy of the combination of an interleukin-23 (IL-23) inhibitor (risankizumab) with a tumour necrosis factor-α (TNF-α) inhibitor (golimumab) in the treatment of psoriasis and psoriatic arthritis. After twelve months of treatment with risankizumab and golimumab, our patient experienced a significant improvement in his psoriasis and psoriatic arthritis without any adverse effects to date.

Association between the interleukin (IL)-17A rs2275913 polymorphism and rheumatoid arthritis susceptibility: a meta-analysis and trial sequential analysis

Objective

This meta-analysis was conducted to investigate the relationship between the interleukin (IL)-17A rs2275913 polymorphism and rheumatoid arthritis (RA) susceptibility.

Methods

Eligible studies were retrieved from PubMed, Embase, and Web of Science. The fixed- or random-effects model was used to calculate the pooled odds ratios (ORs) and 95% confidence intervals (95%CIs) on the basis of heterogeneity.

Results

Overall, 11 studies containing 4019 RA patients and 4137 controls were included in this meta-analysis. The results suggested a significant association between the IL-17A rs2275913 polymorphism and RA susceptibility in the overall population (allelic model A vs. G: OR = 0.89, 95%CI: 0.83–0.95; heterozygote model GA vs. GG: OR = 0.87, 95%CI: 0.78–0.96; homozygote model AA vs. GG: OR = 0.82, 95%CI: 0.71–0.96; dominant model GA + AA vs. GG: OR = 0.86, 95%CI: 0.78–0.94). In the subgroup analyses, the IL-17A rs2275913 polymorphism was significantly associated with RA risk in Europeans (allelic model A vs. G: OR = 0.87, 95%CI: 0.78–0.97; heterozygote model GA vs. GG: OR = 0.79, 95%CI: 0.68–0.93; dominant model GA + AA vs. GG: OR = 0.79, 95%CI: 0.68–0.92), but not in Africans or Americans.

Conclusion

This study suggests that the IL-17A rs2275913 polymorphism is significantly associated with RA susceptibility in Europeans.

INPLASY registration number: INPLASY202170056.

Variant to Gene Mapping to Discover New Targets for Immune Tolerance

The breakdown of immunological tolerance leads to autoimmune disease, and the mechanisms that maintain self-tolerance, especially in humans, are not fully understood. Genome-wide association studies (GWAS) have identified hundreds of human genetic loci statistically linked to autoimmune disease risk, and epigenetic modifications of DNA and chromatin at these loci have been associated with autoimmune disease risk. Because the vast majority of these signals are located far from genes, identifying causal variants, and their functional consequences on the correct effector genes, has been challenging. These limitations have hampered the translation of GWAS findings into novel drug targets and clinical interventions, but recent advances in understanding the spatial organization of the genome in the nucleus have offered mechanistic insights into gene regulation and answers to questions left open by GWAS. Here we discuss the potential for 'variant-to-gene mapping' approaches that integrate GWAS with 3D functional genomic data to identify human genes involved in the maintenance of tolerance.

mRNA expression analysis of interleukins 17A and 17F in bronchial asthmatic patients from Northern Indian population

INTRODUCTION

Asthma being a chronic inflammatory disease concerning to the airways involves genetic and environmental factors. It is known to develop a clinical condition of airway hyper-responsiveness, which induces frequent symptoms in patients such as breathlessness, chest congestion, coughing, and wheezing, particularly during night hours or during early morning hours. The cytokine, Interleukin 17F (IL17F), is important in mediating allergic reactions in the body and regulating the pathophysiology and pathogenesis of asthmatic attacks, as well as airway inflammation, respectively. The Interleukin 17A (IL17A) is involved in increasing the biosynthesis of interleukins IL-6 and IL11. In contrast, IL17F enhances the expression of interleukin IL11 and tumor growth factor, TGF-β.

METHODOLOGY

Standard procedures were followed for collection and processing of blood samples from the subjects (controls and patients, 104 each), isolation of mRNA and to determine the quantities of IgE, and the interlukins (IL17A and IL17F) in the serum. The Real-time PCR and ELISA techniques were employed for synthesis of cDNA and determination of interleukins, respectively, using standard protocols. Early diagnosis of asthma is still a challenge to meet.

RESULTS

The statistical analysis of the data reflected a positive correlation between each of the interleukins (IL-17A and IL17F) and IgE (p = 0.001 and r = 0.41), (p = 0.004 and r = 0.077). The results indicated the upregulation of expression of IL17A and IL17F genes in the patients suffering from asthma.

CONCLUSIONS

This study has indicated that the blood levels of IL-17A and IL17F could be utilized as viable clinical markers for early diagnosis, timely treatment, and proper management of asthma.

Alpha-Glucosidase Inhibitors Alter Gut Microbiota and Ameliorate Collagen-Induced Arthritis

Acarose is an anti-diabetic drug and exhibits anti-arthritic effects. We hypothesized that acarbose influences the gut microbiota to affect the course of arthritis and tested this hypothesis in a collagen-induced arthritis (CIA) murine model. Acarbose in drinking water was administered via gastric gavage started prior to or at the time of CIA induction. Gut microbiota were evaluated with 16S rRNA gene sequencing from fecal pellets collected prior to arthritis induction, during onset of arthritis, and after treatment. Immune response was evaluated by measuring changes in T helper-17 (Th17) and T regulatory (Treg) cells in the spleen and intestine, as well as serum cytokine levels. Before induction of CIA, acarbose significantly reduced the incidence of arthritis and attenuated clinical severity of arthritis. The frequency of Th17 cells was significantly decreased in the intestinal lamina propria in acarbose treated mice. Mice that were treated with acarbose showed significantly increased CD4+CD25+Foxp3+ Treg cells with elevation of Helios and CCR6. A remarkable alteration in microbial community was observed in acarbose treated mice. Bacterial diversity and richness in mice with arthritis were significantly lower than those in acarbose treated groups. The frequency of Firmicutes was significantly reduced after arthritis onset but was restored after treatment with acarbose. The frequency of Lactobacillus, Anaeroplasma, Adlercreutzia, RF39 and Corynebacterium was significantly higher in control groups than in acarbose treated, while Oscillospira, Desulfovibrio and Ruminococcus enriched in acarbose treated group. Miglitol, another α-glucosidase inhibitor showed a similar but less potent anti-arthritic effect to that of acarbose. These data demonstrate that acarbose alleviated CIA through regulation of Th17/Treg cells in the intestinal mucosal immunity, which may have resulted from the impact of acarbose on gut microbial community. Inexpensive antidiabetic drugs with an excellent safety profile are potentially useful for managing rheumatoid arthritis.

Promoter methylation of Bax and Bcl2 genes and their expression in patients with Behcet's disease

BCL2 and BAX genes are a group of signalling inducer and inhibitor genes playing a key role in the process of cellular physiological death (apoptosis). These genes, through the JAK/STAT signalling pathway, affect different cytokines on cell function and subsequently lead to the pathophysiology of diseases, especially autoimmune diseases. In addition, altering the methylation of genes can affect their expression. Since the aetiology and pathology of Behcet's disease is not fully understood, the aim of this study was to determine the methylation pattern of BCL2 and BAX genes in patients with Behcet's disease and compare it with those of control group. This was a case-control study on 51 patients with Behcet and 61 control subjects. Blood samples were received from all subjects. Subsequently, the peripheral blood mononuclear cells (PBMCs) were isolated by Ficoll method and the methylation of the sites was investigated using quantitative methylation specific PCR (qMS-PCR) technique after extraction of DNA by salting out method and its examination with Nano drop. The results of methylation and expression of Bax gene suggest that the methylation level in the patient group significantly increased compared to the healthy individuals (p-value < .05). Furthermore, the results related to Bax gene expression revealed that the mean of gene expression in the patient group has decreased compared to the healthy group, and this decrease was statistically significant (p-value < .05). The rate of expression and methylation of Bcl2 did not indicate any change in the two patient and healthy groups. Given the results of this study, it can be guessed that perhaps DNA methylation is involved in certain conditions of the disease and it may result in regulation of the expression of the involved genes such as Bax gene, in the pathogenesis of the disease.

Applications of RNA interference in the treatment of arthritis

RNA interference (RNAi) is a cellular mechanism for post-transcriptional gene regulation mediated by small interfering RNA (siRNA) and microRNA. siRNA-based therapy holds significant promise for the treatment of a wide-range of arthritic diseases. siRNA selectively suppresses the expression of a gene product and can thus achieve the specificity that is lacking in small molecule inhibitors. The potential use of siRNA-based therapy in arthritis, however, has not progressed to clinical trials despite ample evidence for efficacy in preclinical studies. One of the main challenges to clinical translation is the lack of a suitable delivery vehicle to efficiently and safely access diverse pathologies. Moreover, the ideal targets in treatment of arthritides remain elusive given the complexity and heterogeneity of these disease pathogeneses. Herein, we review recent preclinical studies that use RNAi-based drug delivery systems to mitigate inflammation in models of rheumatoid arthritis and osteoarthritis. We discuss a self-assembling peptide-based nanostructure that demonstrates the potential of overcoming many of the critical barriers preventing the translation of this technology to the clinic.

Multi-dimensional analysis identified rheumatoid arthritis-driving pathway in human T cell

OBJECTIVES

Rheumatoid arthritis (RA) is an autoimmune disease accompanied by lymphocyte infiltration into joint synovium. While T cells are considered to be important for its pathogenesis, the features that are the most relevant to disease and how they change after treatment remain unclear. The aim of this study was to clarify the characteristics of T cells in RA, comprehensively.

METHODS

We enrolled a total of 311 patients with RA and 73 healthy participants, and carefully classified them by disease state, constructed multiple cohorts and analysed clinical samples from them in a stepwise manner. We performed immunophenotyping with multiple evaluation axes, and two independent transcriptome analyses complementary to each other.

RESULTS

We identified that 'effector memory-Tfh' subset was specifically expanded in the peripheral blood (PB) of patients with RA in correlation with disease activity, and reverted after treatment. Besides, we revealed distinct features of T cells in synovial fluid (SF) that the expression of Tfh/Tph-related genes and pro-inflammatory cytokines and chemokines, including CXCL13, were significantly enriched, whereas these phenotype were Th1-like. Finally, we identified specific pathways, such as mTORC1, IL-2-stat5, E2F, cell cycle and interferon-related genes, that were significantly enriched in SF, in particular, as well as PB of untreated patients with RA, and notably, these features reverted after treatment.

CONCLUSION

Our multi-dimensional investigation identified disease relevant T-cell subsets and gene signatures deeply involved in pathogenesis of RA. These findings could aid in our understanding of essential roles of T cells in RA and will facilitate to development better diagnostic and therapeutic interventions.

Amelioration of adjuvant induced arthritis in Sprague Dawley rats through modulation of inflammatory mediators by Ribes alpestre Decne

ETHNOPHARMACOLOGICAL RELEVANCE

Ribes alpestre Decne has been commonly used in the treatment of joint complaints.

AIM OF STUDY

The present study was undertaken to evaluate the antiarthritic potential of ethanolic extract and fractions of Ribes alpestre and to explore its probable mechanism of action.

MATERIAL AND METHODS

Complete Freunds adjuvant induced arthritis in Sprague Dawley rats was used to assess antiarthritic activity of aqueous ethanol extract, butanol and aqueous fractions at 200 mg/kg oral dose for 28 days. Paw volume and diameter, arthritic index, body weight, hematological and biochemical parameters, radiographic and histological analysis of ankle joints were carried out. An array of pro-inflammatory mediators (IL-1β, IL-6, NF-Kβ, TNF-α, COX-2, IL-4, IL-10 and PGE2) were estimated by RT-PCR and enzyme linked immunosorbent assay. Antioxidant capacity was assessed using DPPH and reducing power assays. Qualitative phytochemical screening, total phenolic and flavonoid content and HPLC analysis of aqueous fraction of Ribes alpestre were also carried out.

RESULTS

Significant (p < 0.001) reduction in paw volume and thickness and arthritic score by aqueous ethanolic extract and its fractions has been found. Aqueous ethanolic extract and fractions in particular aqueous fraction considerably prevented decrease in body weight, alterations in hematological parameters. Radiographic and histological examination revealed no significant architectural changes in joints of treated rats. Significant (p < 0.05-0.001) down regulation of pro-inflammatory genes IL-1β, TNF-α, IL-6, COX-2, PGE2 and NF-Kβ alongwith noteworthy increase in levels of IL-4 and IL-10 was recorded among treated animals. Aqueous ethanol extract and its fractions demonstrated notable and concentration dependent (50-6400 μg/ml) antioxidant potential. Qualitative phytochemical analysis of active fraction (aqueous) displayed presence of flavonoids, alkaloids, tannins and glycosides. Besides total phenolic and flavonoid contents has been found to be 179.3 mg GAE/ml and 389.40 μg QE/ml in aqueous fraction of Ribes alpestre respectively. HPLC profile demonstrated presence of quercitin, chlorogenic acid, vanillic acid and cinamic acid in aqueous fraction.

CONCLUSION

Present communication suggests Ribes alpestre a potent antiarthritic therapy by ameliorating adjuvant arthritis in rats by downregulating proinflammatory mediators with up regulation of anti-inflammatory cytokines.

Dioscin, a Steroidal Saponin Isolated from Dioscorea nipponica, Attenuates Collagen-Induced Arthritis by Inhibiting Th17 Cell Response

Dioscin, a steroidal saponin isolated from Dioscorea nipponica Makino, has previously been shown to possess antiarthritic effects. However, the underlying mechanism is still elusive. Herein, we investigated the therapeutic effects of dioscin on collagen-induced arthritis (CIA) in DBA/1 mice and related mechanism. Cytokine production in CII-specific immune responses were measured by enzyme-linked immunosorbent assay (ELISA); Th17 cell-related gene expression, including IL-17A, ROR[Formula: see text] and IL-23p19, were detected by qPCR analysis; Surface marker, T regulatory (Treg) cells and intracellular cytokines (IL-17A and IFN-[Formula: see text]) were evaluated by flow cytometry. We performed Th17 cell differentiation assay in vitro. Results showed that, in vivo, dioscin treatment significantly reduced the severity of CIA, which was accompanied by decreased Th17 response, but not Th1 and Treg response; dioscin-treated mice also showed lower percentage of CD11b[Formula: see text] Gr-1[Formula: see text] neutrophils; In vitro, dioscin treatment suppressed the differentiation of naive CD4[Formula: see text] T cells into Th17 cell and decreased IL-17A production. Collectively, our results indicate that dioscin exerts antiarthritic effects by inhibiting Th17 cell immune response.

Counter-regulation of regulatory T cells by autoreactive CD8+ T cells in rheumatoid arthritis

The mechanisms whereby autoreactive T cells escape peripheral tolerance establishing thus autoimmune diseases in humans remain an unresolved question. Here, we demonstrate that autoreactive polyfunctional CD8⁺ T cells recognizing self-antigens (i.e., vimentin, actin cytoplasmic 1, or non-muscle myosin heavy chain 9 epitopes) with high avidity, counter-regulate Tregs by killing them, in a consistent percentage of rheumatoid arthritis (RA) patients. Indeed, these CD8⁺ T cells express a phenotype and gene profile of effector (eff) cells and, upon antigen-specific activation, kill Tregs indirectly in an NKG2D-dependent bystander fashion in vitro. This data provides a mechanistic basis for the finding showing that AE-specific (CD107a⁺) CD8⁺ T killer cells correlate, directly with the disease activity score, and inversely with the percentage of activated Tregs, in both steady state and follow-up studies in vivo. In addition, multiplex immunofluorescence imaging analyses of inflamed synovial tissues in vivo show that a remarkable number of CD8⁺ T cells express granzyme-B and selectively contact FOXP3⁺ Tregs, some of which are in an apoptotic state, validating hence the possibility that CD8⁺ Teff cells can counteract neighboring Tregs within inflamed tissues, by killing them. Alternatively, the disease activity score of a different subset of patients is correlated with the expansion of a peculiar subpopulation of autoreactive low avidity, partially-activated (pa)CD8⁺ T cells that, despite they conserve the conventional naïve (N) phenotype, produce high levels of tumor necrosis factor (TNF)-α and exhibit a gene expression signature of a progressive activation state. Tregs directly correlate with the expansion of this autoreactive (low avidity) paCD8⁺ TN cell subset in vivo, and efficiently control their differentiation rather their proliferation in vitro. Interestingly, autoreactive high avidity CD8⁺ Teff cells or low avidity paCD8⁺ TN cells are significantly expanded in RA patients who would become non-responders or patients who would become responders to TNF-α inhibitor therapy, respectively. These data provide evidence of a previously undescribed role of such mechanisms in the progression and therapy of RA.

Therapeutic effects of Caesalpinia minax Hance on complete Freund's adjuvant (CFA)-induced arthritis and the anti-inflammatory activity of cassane diterpenes as main active components

ETHNOPHARMACOLOGICAL RELEVANCE

Seeds of Caesalpinia minax Hance called 'Ku-Shi-Lian' (KSL) in China have been used as Zhuang or Dai folk medicines for treatment of common cold, fever, rheumatoid arthritis and dysentery for hundred years.

AIM OF THE STUDY

This study aimed to investigate therapeutic efficacy of KSL extract using complete Freund's adjuvant (CFA) induced arthritis in a rat model and the anti-inflammatory activity of cassane diterpenes as the main active material basis of this herb.

MATERIALS AND METHODS

Arthritis was induced in male Wistar rats (200-220 g) by immunization with CFA. Dexamethasone (DXMS) and Tripterygium glycosides (TG) were chosen as the positive drugs. Water soluble fraction (CMW, 1000 and 2000 mg/kg) and chloroform soluble fraction (CMC, 400 and 800 mg/kg) of KSL were orally administered from day 1 and continued for 21 days. Change of paw swelling perimeter, arthritics score, body weight growth, were observed, and the production of TNF-α, IL-1β and IL-6 in serum were measured by enzyme-linked immunosorbent assay (ELISA). The histological changes in the ankle joint were analyzed in adjuvant induced arthritis rats. Moreover, the inhibitory effect on mRNA expression of proinflammatory cytokine IL-1β, IL-6 and TNF-α of fourteen cassane diterpenes obtained from CMC extract were valued using the RAW 264.7 macrophages cell stimulated by lipopolysaccharide (LPS) assay.

RESULTS

The chloroform soluble fraction (CMC) showed the significantly suppressed change of paw swelling perimeter, arthritics score and increased body weight loss. The overproduction of TNF-α, IL-1β and IL-6 were remarkably suppressed in the serum. Fourteen cassane derivatives as the main constituents of CMC extract showed the promising activity on the expression mRNA of cytokine IL-1β, IL-6 and TNF-α produced by macrophages cells.

CONCLUSIONS

In this study, the chloroform soluble fraction of 'KSL' (seeds of C. minax) was found to exert an anti-RA activity significantly in vivo for the first time, which indicted this fraction might be used as a powerful therapeutic agent for arthritis treatments. Cassane diterpenes, as the main constituents in this fraction, showed the anti-inflammation activity through the regulation of cytokine expression, which might be developed as target-agents for this national herb further developing.

Blocking Matrix Metalloproteinase-9 Abrogates Collagen-Induced Arthritis via Inhibiting Dendritic Cell Migration

Trafficking of dendritic cells (DCs) to lymph nodes (LNs) to present Ags is a crucial step in the pathogenesis of rheumatoid arthritis (RA). Matrix metalloproteinase-9 (MMP-9) is the key molecule for DC migration. Thus, blocking MMP-9 to inhibit DC migration may be a novel strategy to treat RA. In this study, we used anti-MMP-9 Ab to treat collagen-induced arthritis (CIA) in DBA/1J mice and demonstrated that anti-MMP-9 Ab treatment significantly suppressed the development of CIA via the modulation of DC trafficking. In anti-MMP-9 Ab-treated CIA mice, the number of DCs in draining LNs was obviously decreased. In vitro, anti-MMP-9 Ab and MMP-9 inhibitor restrained the migration of mature bone marrow-derived DCs in Matrigel in response to CCR7 ligand CCL21. In addition, blocking MMP-9 decreased T and B cell numbers in LNs of CIA mice but had no direct influence on the T cell response to collagen II by CD4⁺ T cells purified from LNs or spleen. Besides, anti-MMP-9 Ab did not impact on the expression of MHC class II, CD40, CD80, CD86, and chemokine receptors (CCR5 and CCR7) of DCs both in vivo and in vitro. Furthermore, we discovered the number of MMP-9^-/- DCs trafficking from footpads to popliteal LNs was dramatically reduced as compared with wild type DCs in both MMP-9^-/- mice and wild type mice. Taken together, these results indicated that DC-derived MMP-9 is the crucial factor for DC migration, and blocking MMP-9 to inhibit DC migration may constitute a novel strategy of future therapy for RA and other similar autoimmune diseases.

Ephedra gerardiana aqueous ethanolic extract and fractions attenuate Freund Complete Adjuvant induced arthritis in Sprague Dawley rats by downregulating PGE2, COX2, IL-1β, IL-6, TNF-α, NF-kB and upregulating IL-4 and IL-10

ETHNOPHARMACOLOGICAL RELEVANCE

The whole plant, roots and stems of Ephedra gerardiana (Family Ephedraceae) have long been used as a folk remedy to treat rheumatism and painful joints in Northern Areas of Pakistan.

AIM OF THE STUDY

The purpose of study was to observe the preventive efficacy of Ephedra gerardiana (EG) aerial parts in treating rheumatoid arthritis using Freund's complete adjuvant (FCA) induced arthritis in rat model and to determine its possible mechanism of action.

MATERIAL AND METHODS

Arthritis was induced in Sprague Dawley rats by immunization with 0.1 ml FCA in left footpad. EG aqueous ethanolic extract (30:70) and its aqueous, n-butanol and ethyl acetate fractions at 200 mg/kg were orally administered from day 0, 30 min prior to adjuvant injection and sustained for 28 days. Paw volume/diameter, arthritic score, body weight, and hematological (WBC, RBC, ESR, Hb and Platelet count) and biochemical (AST, ALT, ALP, urea, creatinine, CRP and RF) parameters were observed. The mRNA expression levels of COX-2, IL-1β, IL-6, NF-kB, TNF-α, IL-4 and IL-10 were measured by real time reverse transcription polymerase chain reaction (RT-PCR) while, PGE2 and TNF-α levels in serum samples were measured by Enzyme linked immunosorbent assay (ELISA). Moreover, radiographs of hind paws and histological changes in ankle joint were analyzed in adjuvant injected rats. In addition, anti-oxidant activity of plant extract and fractions was also evaluated using DPPH and reducing power assays. Also, preliminary phytochemistry and total phenolic and flavonoid contents were investigated in most active fraction (aqueous fraction).

RESULTS

EG extract and fractions (notably aqueous fraction) significantly suppressed paw swelling and arthritic score, prevented cachexia and remarkably ameliorated hematological and biochemical changes. Furthermore, the overproduction of PGE2, COX-2, IL-1β, IL-6, NF-kB and TNF-α were remarkably attenuated in all EG treated rats, however, IL-4 and 10 were markedly increased. The radiographic and histopathologic improvement in joint architecture was also observed in EG treated rats. Piroxicam, used as reference drug, also significantly suppressed arthritis. Additionally, plant exhibited notable anti-oxidant activity and phytochemical analysis revealed the presence of alkaloids, flavonoids, phenols, tannins, saponins and glycosides.

CONCLUSION

These results indicate that EG extract and fractions significantly attenuated adjuvant arthritis in rats by decreasing the levels of aforementioned pro-inflammatory and increasing the levels of anti-inflammatory mediators. This suggests that Ephedra gerardiana aerial parts might be used as a therapeutic agent for treating human arthritis.

4-(Hydroxymethyl)catechol Extracted From Fungi in Marine Sponges Attenuates Rheumatoid Arthritis by Inhibiting PI3K/Akt/NF-κB Signaling

Rheumatoid arthritis (RA) is a progressive autoimmune disease specific to synovial joints; it causes joint damage and other systemic abnormalities, thereby leading to physical disability and early mortality. Marine sponge-derived fungi, Pestalotiopsis sp., secrete immunosuppressive compounds in the culture broth. In the present study, we isolated 4-(hydroxymethyl)catechol (4-HMC) from these fungal species, and evaluated its anti-RA effects using a murine collagen-induced arthritis model and tumor necrosis factor-α-stimulated human RA synovial fibroblasts. Oral 4-HMC administration decreased the clinical arthritis score, paw thickness, histologic and radiologic changes, and serum IgG1 and IgG2a levels. It prevented the proliferation of helper T (Th) 1/Th17 CD4⁺ lymphocytes isolated from inguinal lymph nodes, thereby reducing inflammatory cytokine production in CIA mice. It decreased the expression of inflammatory mediators, including cytokines and matrix metalloproteinases (MMPs), both in vitro and in vivo. We observed that 4-HMC suppresses Th immune responses and MMP expression to inhibit inflammatory cytokine production in human RA synovial fibroblasts by modulating the PI3K/Akt/NF-κB pathway. These results verify the anti-RA potential of 4-HMC.

Act1 is a negative regulator in T and B cells via direct inhibition of STAT3

Although Act1 (adaptor for IL-17 receptors) is necessary for IL-17-mediated inflammatory responses, Act1- (but not Il17ra-, Il17rc-, or Il17rb-) deficient mice develop spontaneous SLE- and Sjögren's-like diseases. Here, we show that Act1 functions as a negative regulator in T and B cells via direct inhibition of STAT3. Mass spectrometry analysis detected an Act1-STAT3 complex, deficiency of Act1 (but not Il17ra-, Il17rc-, or Il17rb) results in hyper IL-23- and IL-21-induced STAT3 activation in T and B cells, respectively. IL-23R deletion or blockade of IL-21 ameliorates SLE- and Sjögren's-like diseases in Act1-/- mice. Act1 deficiency results in hyperactivated follicular Th17 cells with elevated IL-21 expression, which promotes T-B cell interaction for B cell expansion and antibody production. Moreover, anti-IL-21 ameliorates the SLE- and Sjögren's-like diseases in Act1-deficient mice. Thus, IL-21 blocking antibody might be an effective therapy for treating SLE- and Sjögren's-like syndrome in patients containing Act1 mutation.

Sodium chloride triggers Th17 mediated autoimmunity

The detrimental effects of a high-salt diet on human health have received much attention in the past few years. While it has been well established that high dietary salt intake is related to cardiovascular diseases, there is growing evidence that excess salt also affects the immune system and might be considered as a risk factor in autoimmune diseases such as multiple sclerosis (MS). Several studies have implicated T helper 17 cells (Th17) in the pathogenesis of MS. We and others recently demonstrated that excessive salt enhances the differentiation of Th17 cells, inducing a highly pathogenic phenotype that aggravates experimental neuroinflammation. Moreover, a diet rich in sodium affects intestinal microbiota alongside increased intestinal Th17 cells, thus linking the detrimental effects of high salt consumption to the gut-immune axis. First human studies revealed an association of increased MS disease activity with elevated sodium chloride consumption, while more recent epidemiology studies in larger cohorts suggest no correlation between salt intake and MS. However, it is known that ordinary urinary sodium analyses and nutritional questionnaires do not necessarily correspond to the actual sodium load and more sophisticated analyses are needed. Moreover, studies revealed that sodium can temporarily be stored in the body. This review summarizes recent findings on the impact of salt on the immune system and discusses potential challenges investigating dietary salt intake as a risk factor in MS.

IL-17A - A regulator in acute inflammation: Insights from in vitro, in vivo and in silico studies

Acute inflammation following sterile injury is both inevitable and necessary to restore homeostasis and promote tissue repair. However, when excessive, inflammation can jeopardize the viability of organs and cause detrimental systemic effects. Identifying key-regulators of the immune cascade induced by surgery is vital to attenuating excessive inflammation and its subsequent effects. In this review, we describe the emerging role of IL-17A as a key-regulator in acute inflammation. The role of IL-17A in chronic disease states, such as rheumatoid arthritis, psoriasis and cancer has been well documented, but its significance in acute inflammation following surgery, sepsis, or traumatic injury has not been well studied. We aim to highlight the role of IL-17A in acute inflammation caused by trauma, liver ischemia, and organ transplantation, as well as in post-operative surgical infections. Further investigation of the roles of this cytokine in acute inflammation may stimulate novel therapies or diagnostic modalities.

Impacts of microbiome metabolites on immune regulation and autoimmunity

A vast number of studies have demonstrated a remarkable role for the gut microbiota and their metabolites in the pathogenesis of inflammatory diseases, including multiple sclerosis (MS). Recent studies in experimental autoimmune encephalomyelitis, an animal model of MS, have revealed that modifying certain intestinal bacterial populations may influence immune cell priming in the periphery, resulting in dysregulation of immune responses and neuroinflammatory processes in the central nervous system (CNS). Conversely, some commensal bacteria and their antigenic products can protect against inflammation within the CNS. Specific components of the gut microbiome have been implicated in the production of pro-inflammatory cytokines and subsequent generation of Th17 cells. Similarly, commensal bacteria and their metabolites can also promote the generation of regulatory T-cells (Treg), contributing to immune suppression. Short-chain fatty acids may induce Treg either by G-protein-coupled receptors or inhibition of histone deacetylases. Tryptophan metabolites may suppress inflammatory responses by acting on the aryl hydrocarbon receptor in T-cells or astrocytes. Interestingly, secretion of these metabolites can be impaired by excess consumption of dietary components, such as long-chain fatty acids or salt, indicating that the diet represents an environmental factor affecting the complex crosstalk between the gut microbiota and the immune system. This review discusses new aspects of host-microbiota interaction and the immune system with a special focus on MS as a prototype T-cell-mediated autoimmune disease of the CNS.

GWAS analysis using interspecific backcross progenies reveals superior blue catfish alleles responsible for strong resistance against enteric septicemia of catfish

Infectious diseases pose significant threats to the catfish industry. Enteric septicemia of catfish (ESC) caused by Edwardsiella ictaluri is the most devastating disease for catfish aquaculture, causing huge economic losses annually. Channel catfish and blue catfish exhibit great contrast in resistance against ESC, with channel catfish being highly susceptible and blue catfish being highly resistant. As such, the interspecific backcross progenies provide an ideal system for the identification of quantitative trait locus (QTL). We previously reported one significant QTL on linkage group (LG) 1 using the third-generation backcrosses, but the number of founders used to make the second- and third-generation backcross progenies was very small. Although the third-generation backcross progenies provided a greater power for fine mapping than the first-generation backcrosses, some major QTL for disease resistance may have been missing due to the small numbers of founders used to produce the higher generation backcrosses. In this study, we performed a genome-wide association study using first-generation backcrosses with the catfish 690 K SNP arrays to identify additional ESC disease resistance QTL, especially those at the species level. Two genomic regions on LG1 and LG23 were determined to be significantly associated with ESC resistance as revealed by a mixed linear model and family-based association test. Examination of the resistance alleles indicated their origin from blue catfish, indicating that at least two major disease resistance loci exist among blue catfish populations. Upon further validation, markers linked with major ESC disease resistance QTL should be useful for marker-assisted introgression, allowing development of highly ESC resistant breeds of catfish.

Grape seed proanthocyanidin extract ameliorates murine autoimmune arthritis through regulation of TLR4/MyD88/NF-κB signaling pathway

BACKGROUND/AIMS

Grape seed proanthocyanidin extract (GSPE) has been reported to have a beneficial effect on regulating inf lammation. However, the anti-inflammatory mechanism of GSPE remains unclear. The aim of this study was to verify the influence of GSPE on the Toll-like receptor 4 (TLR4)-mediated signaling pathway in the regulation of murine autoimmune arthritis.

METHODS

Collagen-induced arthritis (CIA) was induced in dilute brown non-agouti (DBA)/1J mice. The mice were treated with GSPE (0 or 100 mg/kg) intraperitoneally. The severity of arthritis was assessed clinically, biochemically, and histologically. Immunostaining for TLR4 was performed. The expressions of TLR4 and downstream signaling molecules were analyzed by Western blot. The effect of GSPE on lipopolysaccharide (LPS)-induced TLR4 activation was also evaluated using RAW264.7 cells and fibroblast-like synoviocytes (FLSs) from patients with rheumatoid arthritis and from those with osteoarthritis.

RESULTS

GSPE attenuated the clinical severity of arthritis and decreased histological damage. GSPE treatment reduced the number of TLR4-stained cells in the synovium of mice with CIA. GSPE also downregulated the expression of TLR4, myeloid differentiation factor 88 (MyD88) and phosphorylated IκBα synovial protein in CIA mice. Concurrently, GSPE inhibited the nuclear translocation of nuclear factor-κB (NF-κB) subunits (p65 and p50). LPS-induced TLR4 activation was suppressed by GSPE in human FLS as well as in murine macrophages in vitro.

CONCLUSIONS

Our results demonstrated that GSPE ameliorated CIA by regulating the TLR4-MyD88-NF-κB signaling pathway.

The Immunoregulation of Th17 in Host against Intracellular Bacterial Infection

T helper 17 cells (Th17) constitute a distinct subset of helper T cells with a unique transcriptional profile (STAT3, RORγ, and RORα), cytokine production pattern (IL17 family), and requirement of specific cytokines for their differentiation (TGF-β, IL6, IL21, and IL23). Recent studies involving experimental animals and humans have shown that Th17/IL17 plays a crucial role in host defense against a variety of pathogens, including bacteria and viruses. The underlying mechanisms by which Th17 performs include dendritic cell (DC) regulation, neutrophil recruitment, Th1 modulation, and T regulatory cell (Treg) balance. In recent years, researchers have generated an accumulating wealth of evidence on the role of Th17/IL17 in protective immunity to intracellular bacterial pathogens, such as Mycobacterium tuberculosis and Chlamydia trachomatis, which are one of the most important pathogens that inflict significant socioeconomic burden across the globe. In this article, we reviewed the current literature on the functions and mechanisms by which Th17/IL17 responds to intracellular bacterial infections. A better understanding of Th17/IL17 immunity to pathogens would be crucial for developing effective prophylactics and therapeutics.

14-3-3z sequesters cytosolic T-bet, upregulating IL-13 levels in TC2 and CD8+ lymphocytes from patients with scleroderma

BACKGROUND

IL-13-producing CD8⁺ T cells have been implicated in the pathogenesis of type 2-driven inflammatory human conditions. We have shown that CD8⁺IL-13⁺ cells play a critical role in cutaneous fibrosis, the most characteristic feature of systemic sclerosis (SSc; scleroderma). However, the molecular mechanisms underlying production of IL-13 and other type 2 cytokines by CD8⁺ T cells remain unclear.

OBJECTIVE

We sought to establish the molecular basis of IL-13 overproduction by CD8⁺ T cells from patients with SSc, focusing on T-bet modulation of GATA-3 activity, which we showed to underlie IL-13 overproduction in CD8⁺IL-13⁺ cells from patients with SSc.

METHODS

Biochemical and biophysical methods were used to determine the expression and association of T-bet, GATA-3, and regulatory factors in CD8⁺ T cells isolated from the blood and lesional skin of patients with SSc with severe skin thickening. Chromatin immunoprecipitation analysis determined GATA-3 binding to the IL-13 promoter. ImageStream analysis and confocal microscopy visualized the subcellular localization of T-bet and GATA-3. Transcript levels were decreased by small interfering RNAs.

RESULTS

Interaction of T-bet with the adaptor protein 14-3-3z in the cytosol of CD8⁺ T cells from patients with SSc reduces T-bet translocation into the nucleus and its ability to associate with GATA-3, allowing more GATA-3 to bind to the IL-13 promoter and inducing IL-13 upregulation. Strikingly, we show that this mechanism is also found during type 2 polarization of CD8⁺ T cells (T_C2) from healthy donors.

CONCLUSIONS

We identified a novel molecular mechanism underlying type 2 cytokine production by CD8⁺ T cells, revealing a more complete picture of the complex pathway leading to SSc disease pathogenesis.

Peripheral Ulcerative Keratitis Associated with Autoimmune Disease: Pathogenesis and Treatment

Peripheral ulcerative keratitis (PUK) is type of crescent-shaped inflammatory damage that occurs in the limbal region of the cornea. PUK is always combined with an epithelial defect and the destruction of the peripheral corneal stroma. PUK may have a connection to systemic conditions, such as long-standing rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), Wegener granulomatosis (WG), relapsing polychondritis, classic polyarteritis nodosa and its variants, microscopic polyangiitis, and Churg-Strauss syndrome. However, the most common connection is with RA, which is also the focus of this review. The pathogenesis of PUK is still unclear. It is thought that circulating immune complexes and cytokines exert an important influence on the progression of this syndrome. Treatment is applied to inhibit certain aspects of PUK pathogenesis.

miR-210 expression in PBMCs from patients with systemic lupus erythematosus and rheumatoid arthritis

BACKGROUND

In hypoxic conditions, miRNA-210 plays an important role in regulating the expression of hypoxia-inducing factor-1α (HIF-1α) and the differentiation of T helper 17 (Th17) cells, and this may be involved in the development and function of the immune system.

AIMS

This study was to investigate the miR-210 expression levels in peripheral blood mononuclear cells (PBMCs) from patients with systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA) and its association with the clinical and laboratory features of both diseases.

METHODS

Real-time quantitative reverse transcription polymerase chain reaction (RT-qPCR) was used to detect miR-210 expression levels in PBMCs from 35 patients with SLE, 38 patients with RA, and 35 healthy controls.

RESULTS

Compared with the healthy controls, the miR-210 expression levels were significantly increased in patients with SLE (P = 0.001) and there was increased significantly expression of miR-210 in SLE with pleuritis (Z = -2.345, P = 0.019) and anti-SSB/La-positive group (Z = -2.076, P = 0.038). However, we have not found the significant correlation between the miR-210 levels and the Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) score (r _s = 0.091, P = 0.602). Although, no significant difference between miR-210 levels in RA patients and those in healthy controls was found (Z = -1.226, P = 0. 220). There was a significant decreased expression of miR-210 in active RA patients than inactive RA patients (Z = -4.011, P < 0.001).

CONCLUSIONS

The dysregulation of miR-210 levels in SLE and RA patients suggests that miR-210 might play an important role in the pathogenesis of these diseases.

Regulation of TH17 Cells and Associated Cytokines in Wound Healing, Tissue Regeneration, and Carcinogenesis

Wound healing is a crucial process which protects our body against permanent damage and invasive infectious agents. Upon tissue damage, inflammation is an early event which is orchestrated by a multitude of innate and adaptive immune cell subsets including TH17 cells. TH17 cells and TH17 cell associated cytokines can impact wound healing positively by clearing pathogens and modulating mucosal surfaces and epithelial cells. Injury of the gut mucosa can cause fast expansion of TH17 cells and their induction from naïve T cells through Interleukin (IL)-6, TGF-β, and IL-1β signaling. TH17 cells produce various cytokines, such as tumor necrosis factor (TNF)-α, IL-17, and IL-22, which can promote cell survival and proliferation and thus tissue regeneration in several organs including the skin, the intestine, and the liver. However, TH17 cells are also potentially pathogenic if not tightly controlled. Failure of these control mechanisms can result in chronic inflammatory conditions, such as Inflammatory Bowel Disease (IBD), and can ultimately promote carcinogenesis. Therefore, there are several mechanisms which control TH17 cells. One control mechanism is the regulation of TH17 cells via regulatory T cells and IL-10. This mechanism is especially important in the intestine to terminate immune responses and maintain homeostasis. Furthermore, TH17 cells have the potential to convert from a pro-inflammatory phenotype to an anti-inflammatory phenotype by changing their cytokine profile and acquiring IL-10 production, thereby limiting their own pathological potential. Finally, IL-22, a signature cytokine of TH17 cells, can be controlled by an endogenous soluble inhibitory receptor, Interleukin 22 binding protein (IL-22BP). During tissue injury, the production of IL-22 by TH17 cells is upregulated in order to promote tissue regeneration. To limit the regenerative program, which could promote carcinogenesis, IL-22BP is upregulated during the later phase of regeneration in order to terminate the effects of IL-22. This delicate balance secures the beneficial effects of IL-22 and prevents its potential pathogenicity. An important future goal is to understand the precise mechanisms underlying the regulation of TH17 cells during inflammation, wound healing, and carcinogenesis in order to design targeted therapies for a variety of diseases including infections, cancer, and immune mediated inflammatory disease.

Role of LncRNA-AF085935, IL-10 and IL-17 in Rheumatoid Arthritis Patients With Chronic Hepatitis C

BACKGROUND

The current study aimed at testing the effect of corticosteroid therapy on serum levels of interleukin-10 (IL-10) and IL-17 as well as lncRNA-AF085935 in patients of rheumatoid arthritis (RA) associated with hepatitis C virus (HCV) and evaluating the usefulness of using these parameters to predict the therapeutic efficacy of steroids in these patients.

METHODS

Thirty healthy control subjects and 65 chronic HCV patients with RA were included in our study. Patients were subjected to clinical examination, abdominal ultrasound, and liver biopsy and received 6-methyl-prednisolone (PDN) 16 mg/day for 48 weeks. Blood samples were collected from all subjects and serum was separated to assess IL-10 and IL-17 by ELISA and HCV RNA and lncRNA-AF085935 by qRT-PCR.

RESULTS

Our study revealed that there were significant increases in serum levels of IL-10, IL-17 and lncRNA-AF085935 in RA patients associated with HCV compared with healthy control subjects. Also there were significant increases in serum levels of IL-10 and HCV RNA and a significant decrease in serum level of IL-17 in patients after corticosteroid therapy, while lncRNA-AF085935 is not significantly changed.

CONCLUSION

LncRNA-AF085935 might be a useful candidate biomarker for the early detection of RA associated with HCV, providing potential new strategies for early screening and therapy of these patients. IL-17 is a non-invasive prognostic marker to predict the efficacy of corticosteroid therapy in RA patients associated with chronic hepatitis C.

IK acts as an immunoregulator of inflammatory arthritis by suppressing TH17 cell differentiation and macrophage activation

Pathogenic T helper cells (TH) and macrophages have been implicated in the development of rheumatoid arthritis (RA), which can lead to severe synovial inflammation and bone destruction. A range of therapies have been widely used for RA, including specific monoclonal antibodies and chemical inhibitors against inflammatory cytokines produced by these cells. However, these have not been sufficient to meet the medical need. Here, we show that in transgenic mice expressing truncated IK (tIK) cytokine, inflammatory arthritis symptoms were ameliorated as the result of suppression of the differentiation of TH1 and TH17 cells and of macrophage activation. During inflammatory responses, tIK cytokine systemically regulated macrophage functions and TH17 cell differentiation through inactivation of the MAPK and NF-κB pathways. Interestingly, the level of tIK cytokine was higher in synovial fluid of RA patients compared with that in osteoarthritis (OA) patients. Our observations suggest that tIK cytokine can counterbalance the induction of inflammatory cells related to RA and thus could be a new therapeutic agent for the treatment of RA.

Inhibitory effects of Saussurea involucrata (Kar. et Kir.) Sch. -Bip. on adjuvant arthritis in rats

ETHNOPHARMACOLOGICAL RELEVANCE

Saussurea involucrate (Kar. et Kir.) Sch. -Bip is an endangered species of the Compositae family, and this species has long been used for the treatment of rheumatoid arthritis, dysmenorrhea, stomachache, and altitude sickness in Uighur folk and Chinese medicine.

AIM OF THE STUDY

This study aimed to investigate the different therapeutic efficacy of alcohol infusion (SEI) and water decoction (SWD) of S. involucrata in treating rheumatoid arthritis using complete Freund's adjuvant (CFA)-induced arthritis (AA) in a rat model.

MATERIALS AND METHODS

Male Wistar rats (160-180g) were immunized by intradermal injection of 0.1mL of CFA into the left hind metatarsal footpad. Aspirin was chosen as the positive drug. Alcohol infusion (SEI, 400 and 800mg/kg) and water decoction (SWD, 443 and 886mg/kg) of S. involucrata aerial parts were orally administered from day 1 and continued for 21 days. Arthritis severity was evaluated by arthritic score, body weight loss, and paw swelling. The levels of TNF-α, IL-β, and IL-6 in the serum of AA rats were detected by enzyme linked immunosorbent assay (ELISA). Histological changes in the ankle joint were also analyzed in the AA rats.

RESULTS

Both SEI and SWD significantly ameliorated AA severity, as suggested by the modulatory effects on body weight loss, paw swelling, and arthritic score. Histopathological improvement in the joint architecture was also observed in the SEI- and SWD-treated AA rats. The overproduction of TNF-α, IL-1β, and IL-6 was remarkably attenuated in the serum of all treated rats. Furthermore, the therapeutic effect of SWD was more potent than that of SEI in treating rheumatoid arthritis using AA in a rat model, which was reported for the first time.

CONCLUSIONS

These results suggested that the extract of S. involucrata significantly attenuated adjuvant arthritis in rats by decreasing the levels of TNF-α, IL-1β, and IL-6 in the serum. S. involucrata has the potential to be regarded as a candidate for the treatment of human arthritis. Moreover, the therapeutic effect of SWD was much better than alcohol infusion, indicting that active constituents are mainly in the water extract, which is helpful for the clinical treatments to choose the appropriate process.

Increase in circulating Th17 cells during anti-TNF therapy is associated with ultrasonographic improvement of synovitis in rheumatoid arthritis

BACKGROUND

Anti-TNF agents have revolutionised rheumatoid arthritis (RA) treatment; however, a third of patients fail to achieve therapeutic responses. Unexpectedly, studies in murine and human arthritis have indicated that anti-TNF treatment can increase circulating T helper 17 (Th17) cells, but the relationship to treatment response is unclear. To identify immune correlates of anti-TNF treatment response, we conducted a longitudinal study using clinical, ultrasound and T cell assessments.

METHODS

Patients with RA (n = 25) were studied at protocol visits during the initial 12 weeks of anti-TNF treatment. Improvement in the disease activity score of 28 joints (DAS28) >1.2 defined treatment responders (n = 16) and non-responders (n = 9). Changes in synovial thickening and vascularity of 10 metacarpophalangeal joints were quantitatively assessed by grey scale and power Doppler ultrasound. The frequency of circulating Th17 cells was determined by IL17 enzyme-linked immunospot assay (Elispot) and flow cytometry (fluorescence-activated cell sorting (FACS)).

RESULTS

The frequency of circulating IL17-producing cells increased significantly 12 weeks after anti-TNF initiation (Elispot median (range) specific spot forming cells (spSFC)/10⁶ 360 (280-645) vs 632 (367 - 1167), p = 0.003). The increase in CD4 + IL17+ cells at 12 weeks was confirmed by FACS (median (range) %, 0.7 (0.5-0.9) vs 1.05 (0.6-1.3); p = 0.01). The increase in circulating Th17 cells inversely correlated with reduction in synovial vascularity (r = -0.68, p = 0.007) and thickening (r = -0.39; p = 0.04). Higher frequencies of circulating Th17 cells at baseline were associated with poorer anti-TNF treatment response defined by ultrasonographic measures.

CONCLUSIONS

These results demonstrate a link between changes in circulating Th17 cells with resolution of ultrasonographic features of synovial inflammation and vascularity during anti-TNF treatment. The findings may reflect redistribution of Th17 cells from inflamed joints or TNF-driven regulation of Th17 cell production.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT01060098 . Registered 29 January 2010.

Computational Analysis Supports an Early, Type 17 Cell-Associated Divergence of Blunt Trauma Survival and Mortality

OBJECTIVE

Blunt trauma patients may present with similar demographics and injury severity yet differ with regard to survival. We hypothesized that this divergence was due to different trajectories of systemic inflammation and utilized computational analyses to define these differences.

DESIGN

Retrospective clinical study and experimental study in mice.

SETTING

Level 1 trauma center and experimental laboratory.

PATIENTS

From a cohort of 493 victims of blunt trauma, we conducted a pairwise, retrospective, case-control study of patients who survived over 24 hours but ultimately died (nonsurvivors; n = 19) and patients who, after ICU admission, went on to be discharged(survivors; n = 19).

INTERVENTIONS

None in patients. Neutralizing anti-interleukin-17A antibody in mice.

MEASUREMENTS AND MAIN RESULTS

Data on systemic inflammatory mediators assessed within the first 24 hours and over 7 days were analyzed with computational modeling to infer dynamic networks of inflammation. Network density among inflammatory mediators in nonsurvivors increased in parallel with organ dysfunction scores over 7 days, suggesting the presence of early, self-sustaining, pathologic inflammation involving high-mobility group protein B1, interleukin-23, and the Th17 pathway. Survivors demonstrated a pattern commensurate with a self-resolving, predominantly lymphoid response, including higher levels of the reparative cytokine interleukin-22. Mice subjected to trauma/hemorrhage exhibited reduced organ damage when treated with anti-interleukin-17A.

CONCLUSIONS

Variable type 17 immune responses are hallmarks of organ damage, survival, and mortality after blunt trauma and suggest a lymphoid cell-based switch from self-resolving to self-sustaining inflammation.

Anti-inflammatory constituents from the root of Litsea cubeba in LPS-induced RAW 264.7 macrophages

Context Litsea cubeba (Lour.) Pers. (Lauraceae) has long been used as a folk remedy in Traditional Chinese Medicine (TCM) for the treatment of rheumatic diseases. Previous studies from our laboratory indicated that L. cubeba extract showed anti-arthritic activity in rats. Objective To study L. cubeba chemically and biologically and to find the potential constituents responsible for its anti-arthritic effect. Materials and methods The compounds were isolated from the root of L. cubeba by column chromatography which eluted with PE:EtOAc gradient system, and the structures were elucidated by detailed spectroscopic data analysis; the anti-inflammatory activity of the isolated compounds was evaluated by lipopolysaccharide (LPS)-induced RAW 264.7 cells and the TNF-α and NO level were measured by ELISA (commercial kit); The iNOS and COX-2 mRNA expression were measured by RT-PCR and the phosphorylation of IκBα, IKKβ, P38 and Akt were determined by western blots. Results A novel 9-fluorenone, 1-ethoxy-3,7-dihydroxy-4,6-dimethoxy-9-fluorenone (1), together with 4 known compounds, namely pinoresinol (2), syringaresinol (3), 9,9'-O-di-(E)-feruloyl-meso-5,5'-dimethoxysecoisolariciresinol (4) and lyoniresinol (5) were isolated from the root of L. cubeba for the first time. The IC50 for NO inhibition on compounds 1 and 4 were 56.1 ± 1.2 and 32.8 ± 2.3 μM, respectively. The IC50 for TNF-α inhibition were 28.2 ± 0.9 and 15.0 ± 1.0 μM, respectively. Both 1 and 4 suppress mRNA expression of iNOS, COX-2 and protein phosphorylation of IκBα, IKKβ in LPS-induced RAW 264.7 cells. Discussion and conclusion Compounds 1 and 4 isolated from L. cubeba exhibited potent anti-inflammatory activity through the NF-κB signal pathway.

Rheumatoid arthritis onset in postmenopausal women: Does the ACPA seropositive subset result from genetic effects, estrogen deficiency, skewed profile of CD4(+) T-cells, and their interactions?

Rheumatoid arthritis (RA) incidence displays a differentiated age-dependent female-to-male ratio in which women outnumber men. Evidence that the peak incidence of RA in women coincides with menopause age, suggests a potential estrogenic role to disease etiology. Estrogens exert physiologically both stimulatory and inhibitory effects on the immune system. Epidemiologic and animal model studies with estrogen deprivation or supplementation suggested estrogens as to play, mainly, a protective role in RA immunopathology. In this review, we propose that some yet unidentified disturbances associated with estrogen circulating levels, differentiated by the menopausal status, play a major role in women's RA susceptibility. We focus on the interaction between estrogen deprivation and genetic risk alleles for anti-citrullinated protein antibodies (ACPA) seropositive RA, as a major driving force for increased immune reactivity and RA susceptibility, in postmenopausal women. This opens up new fields for research concerning the association among different irregular estrogenic conditions, the cytokine milieu, and age/menopausal status bias in RA.

Pain in autoimmune disorders

Most autoimmune diseases are associated with pathological pain development. Autoimmune diseases with pathological pain include complex regional pain syndrome, rheumatoid arthritis, and Guillian-Barré syndrome to name a few. The present Review explores research linking the immune system to the development of pathological pain in autoimmune diseases. Pathological pain has been linked to T-cell activation and the release of cytokines from activated microglia in the dorsal horn of the spinal cord. New research on the role of autoantibodies in autoimmunity has generated insights into potential mechanisms of pain associated with autoimmune disease. Autoantibodies may act through various mechanisms in autoimmune disorders. These include the alteration of neuronal excitability via specific antigens such as the voltage-gated potassium channel complexes or by mediating bone destruction in rheumatoid arthritis. Although more research must be done to understand better the role of autoantibodies in autoimmune disease related pain, this may be a promising area of research for new analgesic therapeutic targets. © 2016 Wiley Periodicals, Inc.

Transcriptional profiling reveals intrinsic mRNA alterations in multipotent mesenchymal stromal cells isolated from bone marrow of newly-diagnosed type 1 diabetes patients

Background

Bone marrow multipotent mesenchymal stromal cells (MSCs) are a diverse subset of precursors that contribute to the homeostasis of the hematopoietic niche. MSCs can be isolated and expanded in vitro and have unique immunomodulatory and regenerative properties that make them attractive for the treatment of autoimmune diseases, including type 1 diabetes (T1D). Whether autologous or allogeneic MSCs are more suitable for therapeutic purposes has not yet been established. While autologous MSCs may present abnormal function, allogeneic cells may be recognized and rejected by the host immune system. Thus, studies that investigate biological characteristics of MSCs isolated from T1D patients are essential to guide future clinical applications.

Methods

Bone marrow-derived MSCs from recently diagnosed type 1 diabetes patients (T1D-MSCs) were compared with those from healthy individuals (C-MSCs) for morphological and immunophenotypic characteristics and for differentiation potential. Bioinformatics approaches allowed us to match absolute and differential gene expression of several adhesion molecules, immune mediators, growth factors, and their receptors involved with hematopoietic support and immunomodulatory properties of MSCs. Finally, the differentially expressed genes were collated for functional pathway enrichment analysis.

Results

T1D-MSCs and C-MSCs were similar for morphology, immunophenotype, and differentiation potential. Our absolute gene expression results supported previous literature reports, while also detecting new potential molecules related to bone marrow-derived MSC functions. T1D-MSCs showed intrinsic abnormalities in mRNA expression, including the immunomodulatory molecules VCAM-1, CXCL12, HGF, and CCL2. Pathway analyses revealed activation of sympathetic nervous system and JAK STAT signaling in T1D-MSCs.

Conclusions

Collectively, our results indicate that MSCs isolated from T1D patients present intrinsic transcriptional alterations that may affect their therapeutic potential. However, the implications of these abnormalities in T1D development as well as in the therapeutic efficacy of autologous MSCs require further investigation.

Electronic supplementary material

The online version of this article (doi:10.1186/s13287-016-0351-y) contains supplementary material, which is available to authorized users.

Abrogation of collagen-induced arthritis by a peptidyl arginine deiminase inhibitor is associated with modulation of T cell-mediated immune responses

Proteins containing citrulline, a post-translational modification of arginine, are generated by peptidyl arginine deiminases (PAD). Citrullinated proteins have pro-inflammatory effects in both innate and adaptive immune responses. Here, we examine the therapeutic effects in collagen-induced arthritis of the second generation PAD inhibitor, BB-Cl-amidine. Treatment after disease onset resulted in the reversal of clinical and histological changes of arthritis, associated with a marked reduction in citrullinated proteins in lymph nodes. There was little overall change in antibodies to collagen or antibodies to citrullinated peptides, but a shift from pro-inflammatory Th1 and Th17-type responses to pro-resolution Th2-type responses was demonstrated by serum cytokines and antibody subtypes. In lymph node cells from the arthritic mice treated with BB-Cl-amidine, there was a decrease in total cell numbers but an increase in the proportion of Th2 cells. BB-Cl-amidine had a pro-apoptotic effect on all Th subsets in vitro with Th17 cells appearing to be the most sensitive. We suggest that these immunoregulatory effects of PAD inhibition in CIA are complex, but primarily mediated by transcriptional regulation. We suggest that targeting PADs is a promising strategy for the treatment of chronic inflammatory disease.