Interleukin-17 gene expression in patients with rheumatoid arthritis

TIPE2 gene transfer ameliorates aging-associated osteoarthritis in a progeria mouse model by reducing inflammation and cellular senescence

Osteoarthritis (OA) pain is often associated with the expression of tumor necrosis factor alpha (TNF-α), suggesting that TNF-α is one of the main contributing factors that cause inflammation, pain, and OA pathology. Thus, inhibition of TNF-α could potentially improve OA symptoms and slow disease progression. Anti-TNF-α treatments with antibodies, however, require multiple treatments and cannot entirely block TNF-α. TNF-α-induced protein 8-like 2 (TIPE2) was found to regulate the immune system's homeostasis and inflammation through different mechanisms from anti-TNF-α therapies. With a single treatment of adeno-associated virus (AAV)-TIPE2 gene delivery in the accelerated aging Zmpste24-/- (Z24-/-) mouse model, we found differences in Safranin O staining intensity within the articular cartilage (AC) region of the knee between TIPE2-treated mice and control mice. The glycosaminoglycan content (orange-red) was degraded in the Z24-/- cartilage while shown to be restored in the TIPE2-treated Z24-/- cartilage. We also observed that chondrocytes in Z24-/- mice exhibited a variety of senescent-associated phenotypes. Treatment with TIPE2 decreased TNF-α-positive cells, β-galactosidase (β-gal) activity, and p16 expression seen in Z24-/- mice. Our study demonstrated that AAV-TIPE2 gene delivery effectively blocked TNF-α-induced inflammation and senescence, resulting in the prevention or delay of knee OA in our accelerated aging Z24-/- mouse model.

Circulating interleukin-39 as a potential biomarker for rheumatoid arthritis diagnosis

BACKGROUND

Imbalances in cytokine networks have been shown to be a possible cause of rheumatoid arthritis (RA). The interleukin (IL)-12 family is involved in the pathogenesis of autoimmune diseases including RA, while IL-39 is a newly discovered member of the IL-12 family, although its role in RA remains unclear. The purpose of the present study was to detect the expression of IL-39 in the sera of patients with RA and its relationship with RA activity.

METHODS

We recruited 46 patients with RA and 35 healthy controls at Ningbo Sixth Hospital. Blood samples were collected for biochemical analysis, and disease activity scores of 28 joints based on C-reactive protein were monitored. Serum concentrations of IL-39 were determined using an enzyme-linked immunosorbent assay. The Pearson correlation test was used to analyze the association between serum IL-39 levels and clinical indicators.

RESULTS

Serum levels of IL-39 were significantly higher in patients with RA compared with healthy controls (p < 0.0001). IL-39 levels positively correlated with rheumatoid factor (RF), erythrocyte sedimentation rate (ESR), and IgM; RF positively correlated with ESR. Receiver operating characteristic curve analysis showed that IL-39 has diagnostic value for RA (p < 0.0001).

CONCLUSIONS

The significant increase of IL-39 levels in serum of patients with RA and its positive correlation with clinical indicators suggest that IL-39 may serve as biomarker for the diagnosis of RA.

Gene Ontology Analysis Highlights Biological Processes Influencing Non-Response to Anti-TNF Therapy in Rheumatoid Arthritis

Anti-TNF therapy has significantly improved disease control in rheumatoid arthritis, but a fraction of rheumatoid arthritis patients do not respond to anti-TNF therapy or lose response over time. Moreover, the mechanisms underlying non-response to anti-TNF therapy remain largely unknown. To date, many single biomarkers of response to anti-TNF therapy have been published but they have not yet been analyzed as a system of interacting nodes. The aim of our study is to systematically elucidate the biological processes underlying non-response to anti-TNF therapy in rheumatoid arthritis using the gene ontologies of previously published predictive biomarkers. Gene networks were constructed based on published biomarkers and then enriched gene ontology terms were elucidated in subgroups using gene ontology software tools. Our results highlight the novel role of proteasome-mediated protein catabolic processes (p = 2.91 × 10⁻¹⁵) and plasma lipoproteins (p = 4.55 × 10⁻¹¹) in anti-TNF therapy response. The results of our gene ontology analysis help elucidate the biological processes underlying non-response to anti-TNF therapy in rheumatoid arthritis and encourage further study of the highlighted processes.

Relationship between polymorphisms in -572G/C interleukin 6 promoter gene polymorphisms (rs1800796) and risk of rheumatoid arthritis: A meta-analysis

AIMS

This meta-analysis was aimed to investigate the association between -572G/C interleukin (IL)-6 gene polymorphism and occurrence risk of rheumatoid arthritis (RA).

METHODS

Literature search was conducted in PubMed, Embase, Springer and Google Scholar up to November 2018. The pooled odds ratios (ORs) and 95% confidence interval (CI) were calculated by Revman 5.3.

RESULTS

A total of six case-control studies were included in this meta-analysis. In the allele model (G vs C), homozygous gene model (GG vs CC), recessive gene model (GG vs GC + CC), and dominant gene model (GG + GC vs CC), the pooled estimate indicated there was significant association between -572G/C IL-6 gene polymorphism and risk of RA. However, no significant statistical results were found in meta-analyses of heterozygote gene models.

CONCLUSIONS

The -572G/C IL-6 gene polymorphism is associated with the risk of RA. The GG genotype may be the main contributor in increasing susceptibility to RA.

Overexpression of miR-101 May Target DUSP1 to Promote the Cartilage Degradation in Rheumatoid Arthritis

This study aimed to explore crucial genes that contribute to the development of rheumatoid arthritis (RA). Three GSE77298, GSE55457, and GSE55235 data sets were used to analyze the differentially expressed genes (DEGs) between RA synovial membrane tissue samples and normal synovial membrane tissue samples. Then, the functional enrichment analysis and protein-protein interactions (PPIs) construction were performed for DEGs. Subsequently, submodule analysis and regulatory network that contained transcription factors (TFs), microRNAs, and their targets were conducted. Finally, small-molecule drugs related to the DEGs were predicted. A total of 173 upregulated and 54 downregulated DEGs identified in at least 2 of 3 data sets. TYROBP, CTSS, MMP9, CXCR4, and CXCL10 were both highlighted in the PPI and submodule networks. In addition, miR-101, IRF1 TF, DUSP1, and CXCR4 had high degree in the regulatory network, and regulation pairs of miR-101-DUSP1 and IRF1 TF-CXCR4 were obtained. Drugs such as alemtuzumab and marimastat were negatively related to expression of the DEGs and might be useful drugs for RA treatment. In addition, most DEGs were involved in innate immune response (e.g., TYROBP, CCL5, CXCL10, FCGR1A, and FCGR3B) and phagosome pathway (e.g., CTSS). We suggested that miR-101 that regulated DUSP1, IRF1 TF that regulated CXCR4, as well as DEGs as TYROBP and CTSS might contribute to the RA pathogenesis. In addition, anti-inflammatory agent alemtuzumab and matrix metalloproteinase inhibitor marimastat might be useful drugs for RA treatment through functioning on their target genes.

Systemic effects of IL-17 in inflammatory arthritis

Inflammatory arthritis occurs in many diseases and is characterized by joint inflammation and damage. However, the inflammatory state in arthritis is commonly associated with systemic manifestations, which are generally linked to a poor prognosis. The pro-inflammatory cytokine IL-17 functions within a complex network of cytokines and contributes to the pathogenesis of various inflammatory diseases. Three IL-17 inhibitors have already been approved for the treatment of psoriasis, psoriatic arthritis, and ankylosing spondylitis. After a brief description of IL-17 and its local effects on joints, this Review focuses on the systemic effects of IL-17 in inflammatory arthritis. Increased circulating concentrations of bioactive IL-17 mediate changes in blood vessels, liver and cardiac and skeletal muscles. The effects of IL-17 on vascular and cardiac cells might contribute to the increased risk of cardiovascular events that occurs in all patients with inflammatory disorders. In the liver, IL-17 contributes to the high circulating concentrations of acute-phase proteins, such as C-reactive protein, and the appearance of liver lesions. In skeletal muscle, IL-17 contributes to muscle contractibility defects and weakness. Thus, targeting IL-17 might have beneficial effects at both local and systemic levels, and could also be proposed for the treatment of a wider range of inflammatory diseases.

Correlation of increased Th17/Treg cell ratio with endoplasmic reticulum stress in chronic kidney disease

To investigate the relationship between the regulatory immune network and endoplasmic reticulum stress (ERS) in patients with different stages of chronic kidney disease (CKD).A total of 91 patients diagnosed with CKD were divided into different groups according to the stage of disease and treatment with hemodialysis (HD) or peritoneal dialysis (PD). Routine blood and biochemical tests were performed in patients in the different CKD groups and in healthy controls (n = 20). The frequencies of T helper type 17 (Th17) and regulatory T (Treg) cells in the overall T cell population were measured by flow cytometric analysis. Levels of Th17 cell (IL-17) and Treg cell (IL-10) cytokines and the ERS markers CCAAT-enhancer-binding protein homologous protein (CHOP) and glucose-regulated protein 78 (GRP78) were measured by enzyme-linked immunosorbent assay in serum samples collected from controls and patients. Correlations between each parameter and serum creatinine were analyzed by Spearman rank correlation and regression test.CKD stage showed a positive correlation with serum creatinine level, and increased and decreased percentages of Th17 and Treg cells, respectively, reflected in an increased Th17/Treg cell ratio. Consistent with this, CKD stage was positively correlated with serum concentrations of IL-17 and negatively correlated with serum IL-10 levels. Moreover, serum levels of CHOP and GRP78 increased with advancing CKD stage. These correlations were most pronounced in patients in the CKD5 group, who also had the poorest response to HD and PD treatment, compared with CKD5 patients in the nondialysis group. Correlation analysis showed that serum levels of CHOP and GRP78 were independently and positively correlated with the ratio of Th17/Treg cells.We have found that an increased Th17/Treg cell ratio and increased serum levels of ERS markers correlate with the progression of CKD. Our results indicate that the interplay between regulation of the immune network and management of ERS is closely associated with the pathogenesis of CKD. Although HD and PD treatment manage chronic kidney conditions and prevent further deterioration of renal function, they have limited effects on improving the immune disorder and relieving ERS. Our study suggests a potential new direction for development of therapeutic strategies in CKD.

Interleukin-35 upregulates OPG and inhibits RANKL in mice with collagen-induced arthritis and fibroblast-like synoviocytes

IL-35 is a novel anti-inflammatory cytokine, but the exact role of IL-35 in the progression of RA remains unclear, especially associated with osteoporosis and bone erosion. The present research has not been reported. Our purpose is to study how IL-35 affects RA bone destruction.

INTRODUCTION

This study investigated the effect of interleukin-35 (IL-35) on OPG and RANKL expression in collagen-induced arthritis (CIA) in rats and in cultured fibroblast-like synoviocytes (FLS).

METHODS

Thirty DBA/1J mice were randomly assigned to three groups (n = 10 per group): the control group, the CIA group, and the CIA + IL-35 group. Collagen-induced arthritis was induced by immunization with collagen. IL-35 was intraperitoneally injected daily for 10 days, starting from the 24(th) day after immunization. FLS cells were isolated and cultured from CIA. The expression of IL-17, RANKL, and OPG was determined by RT-PCR and Western blot. Each experiment was repeated three times.

RESULTS

CIA mice exhibited arthritis symptoms on day 24, followed by a rapid progression of arthritis. The expression of IL-17 and RANKL was increased and the expression of OPG was decreased in CIA mice compared with control mice. IL-35 treatment inhibited the development of arthritis in CIA mice, accompanied by a decrease in the expression of IL-17 and RANKL and an increase in the expression of OPG. Furthermore, IL-35 dose-dependently inhibited the expression of RANKL and increased the expression of OPG in cultured FLS cells.

CONCLUSION

IL-35 inhibits RANKL expression and increases OPG expression in CIA mice. IL-35 may be used for treating rheumatoid arthritis.

Relationship between female genital tract infections, mucosal interleukin-17 production and local T helper type 17 cells

T helper type 17 (Th17) cells play an important role in immunity to fungal and bacterial pathogens, although their role in the female genital tract, where exposure to these pathogens is common, is not well understood. We investigated the relationship between female genital tract infections, cervicovaginal interleukin-17 (IL-17) concentrations and Th17 cell frequencies. Forty-two cytokines were measured in cervicovaginal lavages from HIV-uninfected and HIV-infected women. Frequencies of Th17 cells (CD3(+) CD4(+) IL-17a(+)) were evaluated in cervical cytobrushes and blood by flow cytometry. Women were screened for Chlamydia trachomatis, Neisseria gonorrhoeae, Mycoplasma genitalium, Trichomonas vaginalis and herpes simplex virus 2 by PCR, and candidal infections and bacterial vaginosis by Gram stain. Women with bacterial sexually transmitted infections (STIs), specifically chlamydia and gonorrhoea, had higher genital IL-17 concentrations than women with no STI, whereas women with candidal pseudohyphae/spores had lower IL-17 concentrations compared with women without candidal infections. Viral STIs (herpes simplex virus 2 and HIV) were not associated with significant changes in genital IL-17 concentrations. Genital IL-17 concentrations correlated strongly with other inflammatory cytokines and growth factors. Although Th17 cells were depleted from blood during HIV infection, cervical Th17 cell frequencies were similar in HIV-uninfected and HIV-infected women. Cervical Th17 cell frequencies were also not associated with STIs or candida, although few women had a STI. These findings suggest that IL-17 production in the female genital tract is induced in response to bacterial but not viral STIs. Decreased IL-17 associated with candidal infections suggests that candida may actively suppress IL-17 production or women with dampened IL-17 responses may be more susceptible to candidal outgrowth.

Synovial inflammation, immune cells and their cytokines in osteoarthritis: a review

OBJECTIVE

Although osteoarthritis (OA) is considered a non-inflammatory condition, it is widely accepted that synovial inflammation is a feature of OA. However, the role of immune cells and their cytokines in OA is largely unknown. This narrative systematic review summarizes the knowledge of inflammatory properties, immune cells and their cytokines in synovial tissues (STs) of OA patients.

DESIGN

Broad literature search in different databases was performed which resulted in 100 articles.

RESULTS

Of 100 articles 33 solely investigated inflammation in OA ST with or without comparison with normal samples; the remaining primarily focussed on rheumatoid arthritis (RA) ST. Studies investigating different severity stages or cellular source of cytokines were sparse. OA ST displayed mild/moderate grade inflammation when investigated by means of haematoxylin and eosin (H&E) staining. Most frequently found cells types were macrophages, T cells and mast cells (MCs). Overall the number of cells was lower than in RA, although the number of MCs was as high as or sometimes even higher than in RA ST. Cytokines related to T cell or macrophage function were found in OA ST. Their expression was overall higher than in normal ST, but lower than in RA ST. Their cellular source remains largely unknown in OA ST.

CONCLUSION

Inflammation is common in OA ST and characterized by immune cell infiltration and cytokine secretion. This inflammation seems quantitatively and qualitatively different from inflammation in RA. Further research is needed to clarify the role of inflammation, immune cells and their cytokines in the pathogenesis of OA.

Discovering new clinical markers in the field of glycomics

Glycosylation modifications have been reported in a number of disease states and, as a result, there is significant focus on the discovery and development of glycan-based biomarkers. Glyco-biomarkers have the potential to enhance the efficacy and efficiency of the diagnostic procedures for these diseases.

Interleukin-17 and interleukin-23 in patients with polymyositis and dermatomyositis

OBJECTIVE

To analyse the concentration of interleukin (IL)-17 and IL-23 in serum and ex vivo culture supernatant of peripheral blood mononuclear cells (PBMCs) from patients with polymyositis (PM) and dermatomyositis (DM) compared with healthy controls (HC).

METHODS

Enzyme-linked immunosorbent assay (ELISA) was used to analyse the concentration of IL-17 and IL-23 from 25 patients with PM, 21 patients with DM, and 12 HC in serum or ex vivo culture supernatant of PBMCs following stimulation ex vivo with anti-CD3/CD28 for 72 h.

RESULTS

The levels of IL-23 increased in the serum and culture supernatant of patients with PM and patients with DM compared with HC. By contrast, concentrations of IL-17 in supernatants from patients with PM and DM were not significantly higher than those from HC. We subdivided the group of DM and PM patients into those with early disease versus those with established disease and found that the levels of IL-17 and IL-23 were much higher in early stage compared to established disease.

CONCLUSION

We have demonstrated that stimulated PBMCs from DM and PM patients produce increased levels of IL-23 as compared to HC. IL-17 and IL-23 levels are increased in early as compared to established disease. This provides further evidence that IL-17/IL-23 may play a crucial role in autoimmune diseases.

Increased expression of activation-induced cytidine deaminase is associated with anti-CCP and rheumatoid factor in rheumatoid arthritis

Rheumatoid arthritis (RA) is associated with higher levels of autoantibodies and IL-17. Here, we investigated if ectopic lymphoid follicles and peripheral blood mononuclear cells (PBMCs) from RA patients exhibit increased activation-induced cytidine deaminase (AID), and if increased AID is correlated with serum levels of autoantibodies and IL-17. The results of immunohistochemical staining showed that organized AID(+) germinal centres were observed in six of the 12 RA synovial samples, and AID(+) cells were found almost exclusively in the B-cell areas of these follicles. Aggregated but not organized lymphoid follicles were found in only one OA synovial sample without AID(+) cells. Significantly higher levels of AID mRNA (Aicda) detected by RT-PCR were found in the PBMCs from RA patients than PBMCs from normal controls (P < 0.01). In the PBMCs from RA patients, AID was expressed predominately by the CD10(+)IgM(+)CD20(+) B-cell population and the percentage of these cells that expressed AID was significantly higher than in normal controls (P < 0.01). AID expression in the PBMCs correlated significantly and positively with the serum levels of rheumatoid factor (RF) (P </= 0.0001) and anti-cyclic citrullinated peptide (CCP) (P = 0.0005). Serum levels of IFN-gamma (P = 0.0005) and IL-17 (P = 0.007), but not IL-4, also exhibited positive correlation with the expression of AID. These results suggest that the higher levels of AID expression in B cells of RA patients correlate with, and may be associated with the higher levels of T helper cell cytokines IFN-gamma and IL-17, leading to the development of anti-CCP and RF.

The role of T helper type 17 cells in inflammatory arthritis

While T cells have been implicated in the pathogenesis of inflammatory arthritis for more than three decades, the focus on the T helper type 17 (Th17) subset of CD4 T cells and their secreted cytokines, such as interleukin (IL)-17, is much more recent. Proinflammatory actions of IL-17 were first identified in the 1990s, but the delineation of a distinct Th17 subset in late 2005 has sparked great interest in the role of these cells in a broad range of immune-mediated diseases. This review summarizes current understanding of the role of Th17 cells and their products in both animal models of inflammatory arthritis and human immune-driven arthritides.

The IL-23/Th17 axis in the immunopathogenesis of psoriasis

Abnormal production of inflammatory mediators is believed to play an important role in the pathogenesis of psoriasis. Emerging data, both in mice and in humans, put the spotlight on a new subset of T helper (Th) cells, in part characterized by their production of IL-17 and accordingly named Th17 cells. Here, we review the development, characterization, and function of human Th17 cells as well as the crucial role of IL-23 in the context of Th17-cell-dependent chronic inflammation in psoriasis. We further discuss recent clinical trials targeting the IL-23/Th17 axis in psoriasis.

Regulation and function of proinflammatory TH17 cells

Naïve CD4(+) helper T (TH) cells, upon activation by antigen-presenting cells (APC), differentiate into different types of effector cells that are characterized by their distinct cytokine production profiles and immune regulatory functions. In addition to TH1 and TH2 cells, a third subset of effector TH cells has recently been described and termed TH17. Since their identification, TH17 cells have emerged as crucial players in infectious, inflammatory, and autoimmune diseases, and cancer. In this review, we summarize the latest discoveries on the cytokine-mediated regulation and transcriptional programming of TH17 cells and their roles in different immune responses and diseases.