Circulating levels of Th1 and Th2 chemokines in patients with ankylosing spondylitis

Clinical significance of T helper-1/T helper-2 cytokines in peripheral blood of children with otitis media with effusion and allergic rhinitis

OBJECTIVE

Otitis media with effusion (OME) is a prevalent and costly disease, especially in children. This article analyzed the expression patterns and clinical significance of T helper-1 (Th1)/Th2 cytokines in the peripheral blood of children with OME and allergic rhinitis (AR).

METHODS

Subjects were assigned to the OME + AR group and the Control group (children with OME), with their clinical baseline data documented. The correlations between Th1/Th2 cytokines and between the total nasal symptom score (TNSS) and Th1/Th2 cytokines were analyzed. The risk factors and the predictive value of Th1/Th2 cytokines for OME + AR were analyzed using logistics multivariate regression analysis and receiver operating characteristic curve.

RESULTS

Significant differences were observed in tympanic pressure/speech frequency/air conduction valve/TNSS score/immunoglobulin E (IgE) level between both groups. The OME + AR children exhibited evidently elevated interleukin-2 (IL-2)/tumor necrosis factor-α (TNF-α)/IL-4/IL-10/IL-6 levels and no significant difference in interferon-γ (IFN-γ) level. Th1/Th2 cytokines were remarkably positively-correlated with the TNSS score. IL-2/TNF-α/IL-4/IL-6 were risk factors for OME with AR. The area under the curves (AUCs) of IL-6/IL-2/IL-4/TNF-α levels in predicting the occurrence of OME + AR were 0.805/0.806/0.775/0.781, with sensitivities of 75.76 %/89.39 %/72.21 %/72.73 % and specificities of 74.29 %/61.34 %/72.86 %/70.00 %, and the cut-off values were 239.600/20.300/29.880/34.800 (pg/mL). The AUC of their combination in predicting OME + AR was 0.955 (93.94 % sensitivity, 85.71 % specificity).

CONCLUSION

Th1/Th2 cytokine levels were imbalanced and obviously positively-correlated with the TNSS score in OME + AR children. IL-2, TNF-α, IL-4, and IL-6 levels had auxiliary predictive value in the occurrence of OME + AR.

Chemokine expression in sera of patients with microscopic polyangiitis and granulomatosis with polyangiitis

We evaluated chemokine expression and its correlation with disease activity in patients with microscopic polyangiitis (MPA) and granulomatosis with polyangiitis (GPA) (MPA/GPA). Serum CCL2, CCL4, CCL19, CXCL1, CXCL2, and CX3CL1 level in 80 patients were analysed using multiple enzyme-linked immunosorbent assays. Correlations between variables were investigated using Pearson's correlation analysis, and receiver operator curve analysis was performed to identify optimal CX3CL1 values in determining active disease. Multivariate logistic regression analysis was done to evaluate predictors of active disease. CCL4 (r = 0.251, p = 0.025), CXCL1 (r = 0.270, p = 0.015), and CX3CL1 (r = 0.295, p = 0.008) significantly correlated with BVAS, while CX3CL1 was associated with five-factor score (r =  - 0.290, p = 0.009). Correlations were revealed between CCL2 and CCL4 (r = 0.267, p = 0.017), CCL4 and CXCL1 (r = 0.368, p < 0.001), CCL4 and CXCL2 (r = 0.436, p < 0.001), and CXCL1 and CXCL2 (r = 0.518, p < 0.001). Multivariate analysis revealed serum CX3CL1 levels > 2408.92 pg/mL could predict active disease (odds ratio, 27.401, p < 0.001). Serum chemokine levels of CCL4, CXCL1, and CX3CL1 showed association with disease activity and especially, CX3CL1 > 2408.92 pg/mL showed potential in predicting active MPA/GPA.

Evaluation of interleukins (IL-1α, IL-1Ra, IL-12, IL-17A, IL-31, and IL-33) and chemokines (CXCL10 and CXCL16) in the serum of male patients with ankylosing spondylitis

BACKGROUND

A case-control study was performed to explore eight pro-inflammatory and anti-inflammatory cytokines, namely interleukin (IL)-1α, IL-1Ra (IL-1 receptor antagonist), IL-12, IL-17A, IL-31, IL-33, CXCL10 (C-X-C motif chemokine ligand 10), and CXCL16, with the aim to understand their role in ankylosing spondylitis (AS) pathogenesis and evaluate their utility as markers to differentiate between diseased and healthy individuals. Among these cytokines, IL-31 and CXCL16 have not been well studied in AS.

PATIENTS AND METHODS

The study included 94 male patients with AS and 91 age-matched control males. Interleukin and chemokine levels were measured using ELISA kits.

RESULTS

Serum levels of IL-17A, CXCL10, and CXCL16 were significantly elevated in patients compared to controls, while IL-31 levels were significantly decreased in patients. IL-17A, CXCL10, and CXCL16 were associated with an increased risk of AS, while IL-31 was associated with a decreased risk of disease (odds ratio = 1.22, 1.78, 1.14, and 0.89, respectively). As indicated by the area under the curve (AUC), IL-17A, IL-31, CXCL10, and CXCL16 were potential markers to differentiate between AS patients and controls (AUC = 0.877, 0.735, 0.8, and 0.7, respectively). IL-1α, IL-1Ra, IL-12, and IL-33 levels showed no significant variations between patients and controls.

CONCLUSIONS

Among the eight cytokines examined, IL-17A, CXCL10, and CXCL16 were up-regulated in the serum of AS patients, while IL-31 was down-regulated. The levels of IL-1α, IL-1Ra, IL-12, and IL-33 showed no significant differences between patients and controls. Serum levels of all cytokines were not affected by disease duration, HLA-B27 positivity, or disease activity.

Patients with ankylosing spondylitis present a distinct CD8 T cell subset with osteogenic and cytotoxic potential

OBJECTIVES

Ankylosing spondylitis (AS) is a chronic inflammatory rheumatic disease affecting mainly the axial skeleton. Peripheral involvement (arthritis, enthesitis and dactylitis) and extra-musculoskeletal manifestations, including uveitis, psoriasis and bowel inflammation, occur in a relevant proportion of patients. AS is responsible for chronic and severe back pain caused by local inflammation that can lead to osteoproliferation and ultimately spinal fusion. The association of AS with the human leucocyte antigen-B27 gene, together with elevated levels of chemokines, CCL17 and CCL22, in the sera of patients with AS, led us to study the role of CCR4+ T cells in the disease pathogenesis.

METHODS

CD8+CCR4+ T cells isolated from the blood of patients with AS (n=76) or healthy donors were analysed by multiparameter flow cytometry, and gene expression was evaluated by RNA sequencing. Patients with AS were stratified according to the therapeutic regimen and current disease score.

RESULTS

CD8+CCR4+ T cells display a distinct effector phenotype and upregulate the inflammatory chemokine receptors CCR1, CCR5, CX3CR1 and L-selectin CD62L, indicating an altered migration ability. CD8+CCR4+ T cells expressing CX3CR1 present an enhanced cytotoxic profile, expressing both perforin and granzyme B. RNA-sequencing pathway analysis revealed that CD8+CCR4+ T cells from patients with active disease significantly upregulate genes promoting osteogenesis, a core process in AS pathogenesis.

CONCLUSIONS

Our results shed light on a new molecular mechanism by which T cells may selectively migrate to inflammatory loci, promote new bone formation and contribute to the pathological ossification process observed in AS.

CD_99 G1 neutrophils modulate osteogenic differentiation of mesenchymal stem cells in the pathological process of ankylosing spondylitis

OBJECTIVES

This study aimed to identify the types and heterogeneity of cells within the spinal enthesis and investigate the underlying mechanisms of osteogenesis.

METHODS

Single-cell RNA sequencing was used to identify cell populations and their gene signatures in the spinal enthesis of five patients with ankylosing spondylitis (AS) and three healthy individuals. The transcriptomes of 40 065 single cells were profiled and divided into 7 clusters: neutrophils, monocytic cells, granulomonocytic progenitor_erythroblasts, T cells, B cells, plasma cells and stromal cells. Real-time quantitative PCR, immunofluorescence, flow cytometry, osteogenesis induction, alizarin red staining, immunohistochemistry, short hairpin RNA and H&E staining were applied to validate the bioinformatics analysis.

RESULTS

Pseudo-time analysis showed two differentiation directions of stromal cells from the mesenchymal stem cell subpopulation MSC-C2 to two Cxcl12-abundant-reticular (CAR) cell subsets, Osteo-CAR and Adipo-CAR, within which three transcription factors, C-JUN, C-FOS and CAVIN1, were highly expressed in AS and regulated the osteogenesis of mesenchymal stem cells. A novel subcluster of early-stage neutrophils, CD99_G1, was elevated in AS. The proinflammatory characteristics of monocyte dendritic cell progenitor-recombinant adiponectin receptor 2 monocytic cells were explored. Interactions between Adipo-CAR cells, CD99_G1 neutrophils and other cell types were mapped by identifying ligand-receptor pairs, revealing the recruitment characteristics of CD99_G1 neutrophils by Adipo-CAR cells and the pathogenesis of osteogenesis induced in AS.

CONCLUSIONS

Our results revealed the dynamics of cell subpopulations, gene expression and intercellular interactions during AS pathogenesis. These findings provide new insights into the cellular and molecular mechanisms of osteogenesis and will benefit the development of novel therapeutic strategies.

Comprehensive epigenomic profiling reveals the extent of disease-specific chromatin states and informs target discovery in ankylosing spondylitis

Ankylosing spondylitis (AS) is a common, highly heritable inflammatory arthritis characterized by enthesitis of the spine and sacroiliac joints. Genome-wide association studies (GWASs) have revealed more than 100 genetic associations whose functional effects remain largely unresolved. Here, we present a comprehensive transcriptomic and epigenomic map of disease-relevant blood immune cell subsets from AS patients and healthy controls. We find that, while CD14+ monocytes and CD4+ and CD8+ T cells show disease-specific differences at the RNA level, epigenomic differences are only apparent upon multi-omics integration. The latter reveals enrichment at disease-associated loci in monocytes. We link putative functional SNPs to genes using high-resolution Capture-C at 10 loci, including PTGER4 and ETS1, and show how disease-specific functional genomic data can be integrated with GWASs to enhance therapeutic target discovery. This study combines epigenetic and transcriptional analysis with GWASs to identify disease-relevant cell types and gene regulation of likely pathogenic relevance and prioritize drug targets.

Screening and identification of key chromatin regulator biomarkers for ankylosing spondylitis and drug prediction: evidence from bioinformatics analysis

BACKGROUND

Ankylosing spondylitis (AS) is one of the most common immune-mediated arthritic diseases worldwide. Despite considerable efforts to elucidate its pathogenesis, the molecular mechanisms underlying AS are still not fully understood.

METHODS

To identify candidate genes involved in AS progression, the researchers downloaded the microarray dataset GSE25101 from the Gene Expression Omnibus (GEO) database. They identified differentially expressed genes (DEGs) and functionally enriched them for analysis. They also constructed a protein-protein interaction network (PPI) using STRING and performed cytoHubba modular analysis, immune cell and immune function analysis, functional analysis and drug prediction.The results showed that DEGs were mainly associated with histone modifications, chromatin organisation, transcriptional coregulator activity, transcriptional co-activator activity, histone acetyltransferase complexes and protein acetyltransferase complexes.

RESULTS

The researchers analysed the differences in expression between the CONTROL and TREAT groups in terms of immunity to determine their effect on TNF-α secretion. By obtaining hub genes, they predicted two therapeutic agents, AY 11-7082 and myricetin.

CONCLUSION

The DEGs, hub genes and predicted drugs identified in this study contribute to our understanding of the molecular mechanisms underlying the onset and progression of AS. They also provide candidate targets for the diagnosis and treatment of AS.

A review of the pleiotropic actions of the IFN-inducible CXC chemokine receptor 3 ligands in the synovial microenvironment

Chemokines are pivotal players in instigation and perpetuation of synovitis through leukocytes egress from the blood circulation into the inflamed articulation. Multitudinous literature addressing the involvement of the dual-function interferon (IFN)-inducible chemokines CXCL9, CXCL10 and CXCL11 in diseases characterized by chronic inflammatory arthritis emphasizes the need for detangling their etiopathological relevance. Through interaction with their mutual receptor CXC chemokine receptor 3 (CXCR3), the chemokines CXCL9, CXCL10 and CXCL11 exert their hallmark function of coordinating directional trafficking of CD4+ TH1 cells, CD8+ T cells, NK cells and NKT cells towards inflammatory niches. Among other (patho)physiological processes including infection, cancer, and angiostasis, IFN-inducible CXCR3 ligands have been implicated in autoinflammatory and autoimmune diseases. This review presents a comprehensive overview of the abundant presence of IFN-induced CXCR3 ligands in bodily fluids of patients with inflammatory arthritis, the outcomes of their selective depletion in rodent models, and the attempts at developing candidate drugs targeting the CXCR3 chemokine system. We further propose that the involvement of the CXCR3 binding chemokines in synovitis and joint remodeling encompasses more than solely the directional ingress of CXCR3-expressing leukocytes. The pleotropic actions of the IFN-inducible CXCR3 ligands in the synovial niche reiteratively illustrate the extensive complexity of the CXCR3 chemokine network, which is based on the intercommunion of IFN-inducible CXCR3 ligands with distinct CXCR3 isoforms, enzymes, cytokines, and infiltrated and resident cells present in the inflamed joints.

Assessing the association of leukocyte telomere length with ankylosing spondylitis and rheumatoid arthritis: A bidirectional Mendelian randomization study

Background

Telomere length shortening can cause senescence and apoptosis in various immune cells, resulting in immune destabilization and ageing of the organism. In this study, we aimed to systematically assess the causal relationship of leukocyte telomere length (LTL) with ankylosing spondylitis (AS) and rheumatoid arthritis (RA) using a Mendelian randomization study.

Methods

LTL (n=472174) was obtained from the UK Biobank genome-wide association study pooled data. AS (n=229640), RA (n=212472) were obtained from FinnGen database. MR-Egger, inverse variance weighting, and weighted median methods were used to estimate the effects of causes. Cochran's Q test, MR Egger intercept test, MR-PRESSO, leave-one-out analysis, and funnel plots were used to look at sensitivity, heterogeneity, and multiple effects. Forward MR analysis considered LTL as the exposure and AS, RA as the outcome. Reverse MR analysis considered AS, RA as the exposure and LTL as the outcome.

Results

In the forward MR analysis, inverse variance-weighted and weighted median analysis results indicated that longer LTL might be associated with increased risk of AS (IVW: OR = 1.55, 95% CI: 1.14-2.11, p = 0.006). MR Egger regression analysis showed no pleiotropy between instrumental variables (IVs) (Egger intercept= 0.008, p = 0.294). The leave-one-out analysis showed that each single nucleotide polymorphism (SNP) of AS was robust to each outcome. No significant causal effects were found between AS, RA and LTL in the reverse MR analysis.

Conclusion

Longer LTL may be related with an increased risk of developing AS, and these findings provide a foundation for future clinical research on the causal association between LTL and AS.

How Has Molecular Biology Enhanced Our Undertaking of axSpA and Its Management

PURPOSE

This review aims at investigating pathophysiological mechanisms in spondyloarthritis (SpA). Analysis of genetic factors, immunological pathways, and abnormalities of bone metabolism lay the foundations for a better understanding of development of the axial clinical manifestations in patients, allowing physician to choose the most appropriate therapeutic strategy in a more targeted manner.

RECENT FINDINGS

In addition to the contribution of MHC system, findings emerged about the role of non-HLA genes (as ERAP1 and 2, whose inhibition could represent a new therapeutic approach) and of epigenetic mechanisms that regulate the expression of genes involved in SpA pathogenesis. Increasing evidence of bone metabolism abnormalities secondary to the activation of immunological pathways suggests the development of various bone anomalies that are present in axSpA patients. SpA are a group of inflammatory diseases with a multifactorial origin, whose pathogenesis is linked to the genetic predisposition, the action of environmental risk factors, and the activation of immune response. It is now well known how bone metabolism leads to long-term structural damage via increased bone turnover, bone loss and osteoporosis, osteitis, erosions, osteosclerosis, and osteoproliferation. These effects can exist in the same patient over time or even simultaneously. Evidence suggests a cross relationship among innate immunity, autoimmunity, and bone remodeling in SpA, making treatment approach a challenge for rheumatologists. Specifically, treatment targets are consistently increasing as new drugs are upcoming. Both biological and targeted synthetic drugs are promising in terms of their efficacy and safety profile in patients affected by SpA.

Interrelationship and Sequencing of Interleukins4, 13, 31, and 33 - An Integrated Systematic Review: Dermatological and Multidisciplinary Perspectives

The interrelations and sequencing of interleukins are complex (inter)actions where each interleukin can stimulate the secretion of its preceding interleukin. In this paper, we attempt to summarize the currently known roles of IL-4, IL-13, IL-31, and IL-33 from a multi-disciplinary perspective. In order to conduct a comprehensive review of the current literature, a search was conducted using PubMed, Google Scholar, Medscape, UpToDate, and Key Elsevier for keywords. The results were compiled from case reports, case series, letters, and literature review papers, and analyzed by a panel of multi-disciplinary specialist physicians for relevance. Based on 173 results, we compiled the following review of interleukin signaling and its clinical significance across a multitude of medical specialties. Interleukins are at the bed rock of a multitude of pathologies across different organ systems and understanding their role will likely lead to novel treatments and better outcomes for our patients. New interleukins are being described, and the role of this inflammatory cascade is still coming to light. We hope this multi-discipline review on the role interleukins play in current pathology assists in this scope.

Single Cell Transcriptome and Surface Epitope Analysis of Ankylosing Spondylitis Facilitates Disease Classification by Machine Learning

Ankylosing spondylitis (AS) is an immune-mediated inflammatory disorder that primarily affects the axial skeleton, especially the sacroiliac joints and spine. This results in chronic back pain and, in extreme cases, ankylosis of the spine. Despite its debilitating effects, the pathogenesis of AS remains to be further elucidated. This study used single cell CITE-seq technology to analyze peripheral blood mononuclear cells (PBMCs) in AS and in healthy controls. We identified a number of molecular features associated with AS. CD52 was found to be overexpressed in both RNA and surface protein expression across several cell types in patients with AS. CD16+ monocytes overexpressed TNFSF10 and IL-18Rα in AS, while CD8+ TEM cells and natural killer cells overexpressed genes linked with cytotoxicity, including GZMH, GZMB, and NKG7. Tregs underexpressed CD39 in AS, suggesting reduced functionality. We identified an overrepresented NK cell subset in AS that overexpressed CD16, CD161, and CD38, as well as cytotoxic genes and pathways. Finally, we developed machine learning models derived from CITE-seq data for the classification of AS and achieved an Area Under the Receiver Operating Characteristic (AUROC) curve of > 0.95. In summary, CITE-seq identification of AS-associated genes and surface proteins in specific cell subsets informs our understanding of pathogenesis and potential new therapeutic targets, while providing new approaches for diagnosis via machine learning.

The Potential Role of Genetics, Environmental Factors, and Gut Dysbiosis in the Aberrant Non-Coding RNA Expression to Mediate Inflammation and Osteoclastogenic/Osteogenic Differentiation in Ankylosing Spondylitis

Ankylosing spondylitis (AS) or radiographic axial spondyloarthritis is a chronic immune-mediated rheumatic disorder characterized by the inflammation in the axial skeleton, peripheral joints, and soft tissues (enthesis, fascia, and ligament). In addition, the extra-skeletal complications including anterior uveitis, interstitial lung diseases and aortitis are found. The pathogenesis of AS implicates an intricate interaction among HLA (HLA-B27) and non-HLA loci [endoplasmic reticulum aminopeptidase 1 (ERAP1), and interleukin-23 receptor (IL23R), gut dysbiosis, immune plasticity, and numerous environmental factors (infections, heavy metals, stress, cigarette smoking, etc.) The latter multiple non-genetic factors may exert a powerful stress on epigenetic regulations. These epigenetic regulations of gene expression contain DNA methylation/demethylation, histone modifications and aberrant non-coding RNAs (ncRNAs) expression, leading to inflammation and immune dysfunctions. In the present review, we shall discuss these contributory factors that are involved in AS pathogenesis, especially the aberrant ncRNA expression and its effects on the proinflammatory cytokine productions (TNF-α, IL-17 and IL-23), T cell skewing to Th1/Th17, and osteoclastogenic/osteogenic differentiation. Finally, some potential investigatory approaches are raised for solving the puzzles in AS pathogenesis.

Elevated Th17 cells are associated with cardiovascular complications in ankylosing spondylitis

OBJECTIVE

Patients with ankylosing spondylitis (AS) carry an increased burden of cardiovascular diseases (CVD), but features denoting the development of CVD in AS are unclear. This study aimed to evaluate the percentage and absolute number of lymphocytes and CD4+T cells in AS patients complicated with CVD (AS-CVD) and determine whether circulating Th17 cells are associated with the development of CVD in AS.

METHOD

A total of 117 AS patients (46 had CVD and 71 had no CVD) were enrolled in this retrospective study. The percentage and absolute number of lymphocytes and CD4+T cells were determined by Flow cytometry. Associations between CVD and clinical markers were analyzed using logistic regression.

RESULTS

The ratio of Th17/Treg cells (0.30 vs 0.19, p = 0.014) and the absolute number of Th17 cells (7.27 cells/μL vs 4.34 cells/μL, p < 0.001) was significantly elevated in AS-CVD group compared with AS-no-CVD group. Multivariate logistic regression revealed that elevated Th17 cells (OR = 1.20, p = 0.016) were associated with CVD complications in AS. Receiver operating characteristic (ROC) curves showed a contribution of Th17 cell for distinguishing AS patients with CVD, with the areas under the ROC curve (AUCs) of 0.729 (95%CI: 0.632-0.825, p < 0.001).

CONCLUSION

Our findings provide evidence for the association between Th17 cells and increased cardiovascular risk in AS. Th17 cells may contribute to accelerated atherogenesis and increased cardiovascular burden in AS and be valuable for early assessment and management of AS-CVD.

Identification of immune related cells and crucial genes in the peripheral blood of ankylosing spondylitis by integrated bioinformatics analysis

Background

Ankylosing spondylitis (AS) is a progressive rheumatic disease and studies reveal that the immune system is critical for the pathogenesis of AS. In the present study, various bioinformatics analysis methods were comprehensively applied, designed to identify potential key genes and inflammation states of AS.

Methods

The transcriptome profiles of GSE25101 and GSE73754 obtained from the Gene Expression Omnibus (GEO) database were merged for subsequent analyses. The differentially expressed genes (DEGs) were identified using the Bioconductor package Limma and threshold values. Functional enrichment and pathway enrichment analyses were performed using the clusterProfiler package and Gene Set Enrichment Analysis (GSEA). Next, protein-protein interaction (PPI) network of the identified DEGs was constructed by the online database, the Search Tool for the Retrieval of Interacting Genes (STRING), visualization and analysis were performed through Cytoscape software. Subsequently, we applied CIBERSORT algorithm to identify subpopulation proportions of immune cells in peripheral blood samples. Finally, we validated the hub genes with the GSE18781 dataset. Samples were collected from patients to validate gene and protein expression using qRT-PCR and ELISA.

Results

A total of 334 DEGs were identified, including 182 upregulated and 152 downregulated DEGs, between AS patients and normal human controls, which were primarily involved in immune response, autophagy, and natural killer cell-mediated cytotoxicity. The most prominent module and candidate biomarkers were identified from the PPI network. Biomarkers were selected for validation and their expressions were significantly decreased in peripheral blood samples which was consistent with transcriptome sequencing results. Nine genes with AUC > 0.70 were considered to be AS hub genes for ROC curve analysis, including GZMA, GZMK, PRF1, GNLY, NKG7, KLRB1, KLRD1, IL2RB and CD247. Furthermore, CIBERSORT results suggest that AS contained a higher proportion of CD8+ T cells, naive CD4+ T cells, neutrophils, and lower levels of gamma delta T cells compared with the normal controls.

Conclusion

In this study, we identified DEGs combined with their closely related biological functions and propose that granule-associated proteins and immune infiltration maybe involved in the progression of ankylosing spondylitis. These validated hub genes may provide new perspectives for understanding the molecular mechanisms of ankylosing spondylitis.

Influence of IL10 (rs1800896) Polymorphism and TNF-α, IL-10, IL-17A, and IL-17F Serum Levels in Ankylosing Spondylitis

Ankylosing spondylitis (AS) is a chronic autoimmune inflammatory disease that mainly affects the axial and sacroiliac joints. Single-nucleotide polymorphisms (SNPs) in genes encoding cytokines have been associated with AS, which can interfere with the production of these cytokines and contribute to the development of AS. In order to contribute to a better understanding of the pathology of AS, our objective was to investigate a possible association of the IL10 −1082 A>G SNP (rs1800896) with AS and to evaluate the serum levels of TNF-α, IL-10, IL-17A, and IL-17F in AS patients and controls comparing them with their respective genotypes (TNF rs1800629, IL10 rs1800896, IL17A rs2275913, and IL17F rs763780). Patients and controls were selected from the Maringá University Hospital and the Maringá Rheumatism Clinic, in Paraná State, Southern Brazil, and they were diagnosed by the ASAS Criteria. In total, 149 patients and 169 controls were genotyped for the IL10 −1082 A>G polymorphism using a polymerase chain reaction with sequence specific primers (PCR-SSP); the measurement of TNF-α serum levels was performed through the immunofluorimetric test and IL-10, IL-17A, and IL-17F using an ELISA test. There was a high frequency of the IL10 −1082 G allele in AS patients compared with controls with an odds ratio of 1.83 and 95% confidence interval of 1.32 to 2.54, and a significant difference in the genotype frequencies of the IL10 −1082 A/G+G/G between patients and healthy controls, with an odds ratio of 3.01 and 95% confidence interval of 1.75 to 5.17. In addition, increased serum levels of IL-10 were observed in AS patients: 2.38 (IQR, 0.91) pg/ml compared with controls 1.72 (IQR 0.93) pg/ml (P = 0.01). Our results also showed an association between IL17F rs763780 C/T+T/T genotypes and increased serum levels of IL-17F in patients with AS and also in controls. We can conclude that patients with the A/G and G/G genotypes for −1082 A>G (rs1800896) in the IL10 gene are three times more likely to develop AS, that the serum level of IL-10 was higher in AS patients and that the IL17F rs763780 polymorphism can affect the levels of IL-17F in the serum of patients and controls in the same way.

Biology and Clinical Applicability of Plasma Thymus and Activation-Regulated Chemokine (TARC) in Classical Hodgkin Lymphoma

Thymus and activation-regulated chemokine (TARC) is produced by different cell types and is highly expressed in the thymus. It plays an important role in T cell development, trafficking and activation of mature T cells after binding to its receptor C-C chemokine receptor type 4 (CCR4) and consecutive signal transducer and activator of transcription 6 (STAT6) activation. Importantly, TARC is also produced by malignant Hodgkin and Reed-Sternberg (HRS) cells of classical Hodgkin lymphoma (cHL). In cHL, HRS cells survive and proliferate due to the micro-environment consisting primarily of type 2 T helper (Th2) cells. TARC-mediated signaling initiates a positive feedback loop that is crucial for the interaction between HRS and T cells. The clinical applicability of TARC is diverse. It is useful as diagnostic biomarker in both children and adults with cHL and in other Th2-driven diseases. In adult cHL patients, TARC is also a biomarker for treatment response and prognosis. Finally, blocking TARC signaling and thus inhibiting pathological Th2 cell recruitment could be a therapeutic strategy in cHL. In this review, we summarize the biological functions of TARC and focus on its role in cHL pathogenesis and as a biomarker for cHL and other diseases. We conclude by giving an outlook on putative therapeutic applications of antagonists and inhibitors of TARC-mediated signaling.

Genetic feature engineering enables characterisation of shared risk factors in immune-mediated diseases

BACKGROUND

Genome-wide association studies (GWAS) have identified pervasive sharing of genetic architectures across multiple immune-mediated diseases (IMD). By learning the genetic basis of IMD risk from common diseases, this sharing can be exploited to enable analysis of less frequent IMD where, due to limited sample size, traditional GWAS techniques are challenging.

METHODS

Exploiting ideas from Bayesian genetic fine-mapping, we developed a disease-focused shrinkage approach to allow us to distill genetic risk components from GWAS summary statistics for a set of related diseases. We applied this technique to 13 larger GWAS of common IMD, deriving a reduced dimension "basis" that summarised the multidimensional components of genetic risk. We used independent datasets including the UK Biobank to assess the performance of the basis and characterise individual axes. Finally, we projected summary GWAS data for smaller IMD studies, with less than 1000 cases, to assess whether the approach was able to provide additional insights into genetic architecture of less common IMD or IMD subtypes, where cohort collection is challenging.

RESULTS

We identified 13 IMD genetic risk components. The projection of independent UK Biobank data demonstrated the IMD specificity and accuracy of the basis even for traits with very limited case-size (e.g. vitiligo, 150 cases). Projection of additional IMD-relevant studies allowed us to add biological interpretation to specific components, e.g. related to raised eosinophil counts in blood and serum concentration of the chemokine CXCL10 (IP-10). On application to 22 rare IMD and IMD subtypes, we were able to not only highlight subtype-discriminating axes (e.g. for juvenile idiopathic arthritis) but also suggest eight novel genetic associations.

CONCLUSIONS

Requiring only summary-level data, our unsupervised approach allows the genetic architectures across any range of clinically related traits to be characterised in fewer dimensions. This facilitates the analysis of studies with modest sample size by matching shared axes of both genetic and biological risk across a wider disease domain, and provides an evidence base for possible therapeutic repurposing opportunities.

GM-CSF Primes Proinflammatory Monocyte Responses in Ankylosing Spondylitis

Objectives: GM-CSF is a pro-inflammatory cytokine with multiple actions predominantly on myeloid cells. Enhanced GM-CSF expression by lymphocytes from patients with Ankylosing Spondylitis (AS) has recently been described, however, its potential pathogenic role(s) in AS are unknown. Methods: The effects of GM-CSF on TNF, IL-23, and CCL17 production by blood, PBMCs and isolated CD14+ monocytes from AS patients and healthy controls (HCs) were studied using ELISA. Serum CCL17 and GM-CSF and T cell GM-CSF production were studied in AS patients including pre-and on TNFi therapy. Results: GM-CSF markedly increased TNF production by LPS-stimulated whole blood, peripheral blood mononuclear cells (PBMC) and purified monocytes from AS patients, with 2 h GM-CSF exposure sufficient for monocyte "priming." Blocking of GM-CSF significantly reduced the production of TNF by whole blood from AS patients but not HCs. GM-CSF priming increased IL-23 production from LPS-stimulated AS and HC whole blood 5-fold, with baseline and stimulated IL-23 levels being significantly higher in AS whole blood. GM-CSF also stimulated CCL17 production from AS and HC blood and CCL17 levels were elevated in AS plasma. GM-CSF could be detected in plasma from 14/46 (30%) AS patients compared to 3/18 (17%) HC. Conclusion: We provide evidence that GM-CSF primes TNF and IL-23 responses in myeloid cells from AS patients and HC. We also show CCL17 levels, downstream of GM-CSF, were elevated in plasma samples of AS patients. Taken together these observations are supportive of GM-CSF neutralization as a potential novel therapeutic approach for the treatment of AS.

The imbalance of Th1/Th2 triggers an inflammatory response in chicken spleens after ammonia exposure

Ammonia is a hazardous environmental pollutant that can be harmful to animal health. In this study, we aimed to evaluate the effect of ammonia exposure on broiler chicken spleens. We randomly divided one hundred twenty 1-day-old broiler chickens into 3 groups and raised them with exposure to different ammonia concentrations (low, middle, and high); at 42 D of age, the chicken spleens were extracted. We observed histopathologic changes in spleen tissues by microscopy and measured the expression of Th1/Th2 secreted cytokines (interleukin [IL]-1β, IL-2, IL-4, IL-6, IL-10, interferon-γ [IFN-γ], tumor necrosis factor-α) by RT-PCR. We also measured the expression of nuclear receptor-κB (NF-κB) pathway–related genes (cyclooxygenase-2 [COX-2], nitric oxide synthase [iNOS], and prostaglandin synthetase [PGE]) in spleens by RT-PCR and Western blot analysis. Histopathologic observations indicated that the spleen tissues were seriously injured in the high ammonia concentration group. There was abnormal cytokine expression, including increased IL-4, IL-6, and IFN-γ and decreased IL-2, which indicated an imbalance in the Th1/Th2 response. The proinflammatory factors such as NF-κB, COX-2, iNOS, and PGE were upregulated in the high ammonia group. In conclusion, this study illustrated that ammonia exposure led to a Th1/Th2 immune imbalance and triggered the NF-κB pathway, causing inflammatory damage to the spleen.

Genomic, proteomic, and immunologic associations with a durable complete remission of measurable metastatic melanoma induced by a patient-specific dendritic cell vaccine

This report describes efforts to understand the immune mechanism of action that led to a complete response in a patient with progressive, refractory, metastatic melanoma after treatment with a therapeutic vaccine consisting of autologous dendritic cells (DC) loaded with autologous tumor antigens (ATA) derived from cells that were self-renewing in cell culture. Her histocompatibility type proved to be HLA B27 with extensive mutations in the HLA-A locus. Exomic analysis of proliferating tumor cells revealed more than 2800 non-synonymous mutations compared to her leukocytes. Histology of resected tumor lesions showed no evidence of an existing or suppressed immune response. In in vitro mixed cell cultures, DC loaded with ATA induced increased IL-22 expression, and a four-fold increase in CD8 + T lymphocytes. Cryopreserved blood samples obtained at week-0, 1 week before the first of three-weekly vaccine injections, and at week-4, 1 week after the third dose, were analyzed by protein array and compared for 110 different serum markers. At baseline, she had marked elevations of amyloid A, IL-12p40, IL21, IL-22, IL-10, IL-16, GROa, TNF-alpha, IL-3, and IL-2, and a lesser elevation of IL-15. One week after 3 weekly vaccinations she had a further 80% increase in amyloid A, a further 66% increase in IL-22, a 92% decrease in IL12p40, a 45% decrease in TGF-β and 26% decrease in IL-10. The data suggested that by 3 weeks after the first DCV injection, vaccine-induced changes in this particular patient were most consistent with enhanced innate and Th1 immune responses rather than Th2 or Th17.

Ankylosing spondylitis: etiology, pathogenesis, and treatments

Ankylosing spondylitis (AS), a common type of spondyloarthropathy, is a chronic inflammatory autoimmune disease that mainly affects spine joints, causing severe, chronic pain; additionally, in more advanced cases, it can cause spine fusion. Significant progress in its pathophysiology and treatment has been achieved in the last decade. Immune cells and innate cytokines have been suggested to be crucial in the pathogenesis of AS, especially human leukocyte antigen (HLA)‑B27 and the interleukin‑23/17 axis. However, the pathogenesis of AS remains unclear. The current study reviewed the etiology and pathogenesis of AS, including genome-wide association studies and cytokine pathways. This study also summarized the current pharmaceutical and surgical treatment with a discussion of future potential therapies.

Aspects of intradermal immunization with different adjuvants: The role of dendritic cells and Th1/Th2 response

Intradermal (i.d.) application of vaccine is promising way how to induce specific immune response against particular pathogens. Adjuvants, substances added into vaccination dose with the aim to increase immunogenicity, play important role in activation of dendritic cells with subsequent activation of lymphocytes. They can, however, induce unwanted local reactions. The aim of the study was to determine the effect of i.d. administration of model antigen keyhole limped hemocyanine alone or with different adjuvants-aluminium hydroxide and oil-based adjuvants-on local histopathological reaction as well as dendritic cell activation at the site of administration and local cytokine and chemokine response. This was assessed at 4 and 24 hours after application. Selection of the adjuvants was based on the fact, that they differently enhance antibody or cell-mediated immunity. The results showed activation of dendritic cells and both Th1 and Th2 response stimulated by oil-based adjuvants. It was associated with higher expression of set of genes, incl. chemokine receptor CCR7 or Th1-associated chemokine CXCL10 and cytokine IFNγ. Application of the antigen with aluminium hydroxide induced higher expression of Th2-associated IL4 or IL13. On the other hand, both complete and incomplete Freund´s adjuvants provoked strong local reaction associated with influx of neutrophils. This was accompanied with high expression of proinflammatory IL1 or neutrophil chemoattractant CXCL8. Surprisingly, similarly strong local reaction was detected also after application of aluminium hydroxide-based adjuvant. The best balanced local reaction with sufficient activation of immune cells was detected after application of oil-based adjuvants Montanide and Emulsigen.

Identification of pathways significantly associated with spondyloarthropathy/ankylosing spondylitis using the sub‑pathway method

The aim of the present study was to extract potential sub-pathway biomarkers for spondyloarthropathy (SpA)/ankylosing spondylitis (AS) using a sub-pathway strategy. SpA/AS-relevant data, reference pathways and long non-coding (lnc)RNA-micro (mi)RNA-mRNA interactions were downloaded. The seed pathways based on Kyoto Encyclopedia of Genes and Genomes pathways and the mRNAs in the co-expressed lncRNA-mRNA interactions were extracted. Sub-pathways regulated by lncRNA were selected after establishing condition-specific lncRNA competitively regulated pathways (LCRP) network. Significant sub-pathways were further identified using the attract method. These significant sub-pathways were evaluated in the other independent published AS microarray data (E-GEOD-25101) using in silico validation. In addition, to uncover SpA/AS-relevant lncRNAs, the degree analysis for all nodes in the LCRP network was conducted. A total of 35 lncRNAs, 131 mRNAs and 145 co-expressed interactions were identified. When entering these 131 mRNAs into the reference pathways, 82 seed pathways were extracted, which were transformed into undirected graphs, and the 35 lncRNAs were mapped to the pathway graphs to further establish the condition-specific LCRP network. Based on degree analysis, four hub lncRNAs were selected, including C14orf169, LINC00242, LINC00116 and LINC00482. It was identified that 35 lncRNAs competitively regulating sub-pathways were involved in 56 complete pathways. Among these, the top three sub-pathways were path: 04010_1, which was a subregion of the mitogen-activated protein kinase (MAPK) signaling pathway; path: 04062-1, an important subregion in the chemokine signaling pathway; and path: 04066_2, was a part of HIF-1 signaling pathway. Furthermore, it was validated consistently in the separate microarray data set E-GEOD-25101. Cancer-associated pathways and hub node C14orf169 were identified in validation. Sub-pathways, including the MAPK signaling pathway and chemokine signaling pathway, and hub lncRNA (C14orf169) may serve important roles in SpA/AS.

The role of interleukin-4 in rheumatic diseases

Rheumatism is a group of diseases, most of which are autoimmune diseases, that violate joints, bones, muscles, blood vessels and related soft tissue. As is well known, cytokines play a role in the pathogenesis of several rheumatic diseases, such as rheumatoid arthritis, spondyloarthritides, and systemic lupus erythematosus. Recently, the role of interleukin-4 (IL-4), which may participate in the mechanism of rheumatism, have been discovered. It is reported that IL-4 takes part in the regulation of T cell activation, differentiation, proliferation, and survival of different T cell types. IL-4 also has an immunomodulatory effect on B cells, mast cells, macrophages, and many cell types. A review of the literature on functions of IL-4 in rheumatic diseases is presented.

IP-10 and RANTES as biomarkers for pulmonary tuberculosis diagnosis and monitoring

OBJECTIVE

We aimed to determine whether IP-10 and RANTES plasma levels can be used in diagnosis and monitoring of pulmonary tuberculosis (PTB).

METHODS

Plasma levels of cytokines/chemokines were measured using a Bio-Plex^® multiplex cytokine assay system in a cohort containing 457 clinically suspected PTB patients including a training set (n = 41)and two independent test sets A (n = 242) and B (n = 174).

RESULTS

Plasma levels of IP-10 and RANTES were significantly higher in PTB patients than healthy controls' in both training and independent test sets (P < 0.05). Compared with other combinations, the combination of IP-10 and RANTES had the best performance with an AUC of 1.0 in training set. The performance characteristic of this model was successfully validated in independent test set A although this combination only resulted in a slightly improvement of AUC value in independent test set B. Plasma IP-10 and RANTES levels were weakly and positively correlated with blood glucose concentrations. Moreover, IP-10 levels were positively correlated with CRP and ESR in PTB patients. Furthermore, in response to therapy, both IP-10 and RANTES levels significantly decreased over the period of 6 months (P < 0.001).

CONCLUSIONS

Taken together, combination of IP-10 and RANTES could be potentially used as diagnostic and monitoring biomarker in PTB management.

Serum IL-6 correlates with axial mobility index (Bath Ankylosing Spondylitis Metrology Index) in Brazilian patients with ankylosing spondylitis

Introduction

Ankylosing spondylitis (AS) is a chronic disease featuring axial changes, peripheral arthritis and systemic involvement. Proinflammatory cytokines are probably involved in AS pathogenesis. The relationship of circulating cytokines with instruments of AS evaluation is an open field of research.

Objective

The aim of this study was to compare serum levels of cytokines in AS patients and healthy controls, and search for correlations of cytokines with indexes of disease activity and quality of life.

Patients and methods

In this cross-sectional study, 32 AS patients and 32 age- and sex- matched controls were evaluated. Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), Bath Ankylosing Spondylitis Funcional Index (BASFI), Bath Ankylosing Spondylitis Metrology Index (BASMI), Ankylosing Spondylitis Disease Activity Score-C reactive protein (ASDAS-CRP), Maastricht Ankylosing Spondylitis Enthesitis Score (MASES), Ankylosing Spondylitis Quality of Life (ASQol) and Patient Global Assessment score were measured in AS patients. The soluble cytokines IL-6, IL-8, IL-1, IL-10, TNF-α, IL-12p70 and IL-17 were quantified by flow cytometry. IL-23 concentrations were measured using an enzyme-linked immunosorbent assay.

Results

Overall, AS patients were predominantly males (59.4%) and Caucasians (96.9%). Mean age was 46.9±10.7 years. Human leukocyte antigen B27 was present in 70% of cases. Concentrations of IL-6, IL-8, IL-10 and TNF-α were higher in AS cases than controls (p<0.05). Mean concentration of IL-6 correlated with the BASMI, an index of axial mobility (r=0.354, p=0.047). Anti-TNF intake (present in 21 patients, 65.6%) associated with a high BASMI (p=0.042) and lower quality of life as measured using the ASQol scale (p=0.009).

Conclusion

A proinflammatory cytokine profile predominated in AS patients, but interestingly, the IL-10 concentrations were also elevated, pointing to a suppressive control of inflammation. A defined correlation of serum IL-6 with the BASMI suggests a role for this cytokine in axial disease. Anti-TNF users showed more axial activity and lower quality of life.

TNF and granulocyte macrophage-colony stimulating factor interdependence mediates inflammation via CCL17

TNF and granulocyte macrophage-colony stimulating factor (GM-CSF) have proinflammatory activity and both contribute, for example, to rheumatoid arthritis pathogenesis. We previously identified a new GM-CSF→JMJD3 demethylase→interferon regulatory factor 4 (IRF4)→CCL17 pathway that is active in monocytes/macrophages in vitro and important for inflammatory pain, as well as for arthritic pain and disease. Here we provide evidence for a nexus between TNF and this pathway, and for TNF and GM-CSF interdependency. We report that the initiation of zymosan-induced inflammatory pain and zymosan-induced arthritic pain and disease are TNF dependent. Once arthritic pain and disease are established, blockade of GM-CSF or CCL17, but not of TNF, is still able to ameliorate them. TNF is required for GM-CSF-driven inflammatory pain and for initiation of GM-CSF-driven arthritic pain and disease, but not once they are established. TNF-driven inflammatory pain and TNF-driven arthritic pain and disease are dependent on GM-CSF and mechanistically require the same downstream pathway involving GM-CSF→CCL17 formation via JMJD3-regulated IRF4 production, indicating that GM-CSF and CCL17 can mediate some of the proinflammatory and algesic actions of TNF. Given we found that TNF appears important only early in arthritic pain and disease progression, targeting a downstream mediator, such as CCL17, which appears to act throughout the course of disease, could be effective at ameliorating chronic inflammatory conditions where TNF is implicated.

Effect of resistant and digestible rice starches on human cytokine and lactate metabolic networks in serum

Resistant starch generated after treating ordinary starch is of great significance to human health in the countries with overnutrition. However, its functional evaluation in the human body has been rarely reported. By determining the lactate metabolic flux, 12 serum enzymes expression level and 38 serum cytokines in healthy volunteers, the variation in cytokine network and lactate metabolic network in serum were investigated to compare the mechanism of the physiological effects between the two starches. The results indicated that compared with digestible starch, resistant starch had anti-inflammatory effects, increased anabolism, and decreased catabolism. Further, the intercellular communication networks including cytokine and lactate metabolic networks were mapped out. The relationship suggested that resistant starch might affect and control the secretion of cytokines to regulate lactate metabolic network in the body, promoting the development of immunometabolism.

Pharmacological Inactivation of Src Family Kinases Inhibits LPS-Induced TNF-α Production in PBMC of Patients with Behçet's Disease

Behçet's disease (BD) is a multisystemic chronic inflammatory disease characterized by relapsing oral and genital ulcers, uveitis, and skin lesions. The pathogenesis of BD is still unknown. Aberrant production of some cytokines/chemokines plays an important role in the pathogenesis of various inflammatory diseases. Revealing a key signaling regulatory mechanism involved in proinflammatory cytokines/chemokines production is critical for understanding of the pathogenesis of BD. The aim of this study was to determine the role of Src family kinases (SFKs) in production of some LPS-induced proinflammatory cytokines/chemokines in peripheral blood mononuclear cells (PBMC) of active BD patients. Chemical inhibition of SFKs activity impaired LPS-induced TNF-α production in PBMC of active BD patients, suggesting that modulating SFKs activity may be a potential target for BD treatment.