Identification of sex-specific biomarkers related to programmed cell death and analysis of immune cells in ankylosing spondylitis.

Ankylosing spondylitis (AS) stands as a persistent inflammatory ailment predominantly impacting the axial skeleton, with the immune system and inflammation intricately entwined in its pathogenesis. This study endeavors to elucidate gender-specific patterns in immune cell infiltration and diverse forms of cell demise within the AS milieu. The aim is to refine the diagnosis and treatment of gender-specific AS patients, thereby advancing patient outcomes. In the pursuit of our investigation, two datasets (GSE25101 and GSE73754) pertinent to ankylosing spondylitis (AS) were meticulously collected and normalized from the GEO database. Employing the CIBERSORT algorithm, we conducted a comprehensive analysis of immune cell infiltration across distinct demographic groups and genders. Subsequently, we discerned differentially expressed genes (DEGs) associated with various cell death modalities in AS patients and their healthy counterparts. Our focus extended specifically to ferroptosis-related DEGs (FRDEGs), cuproptosis-related DEGs (CRDEGs), anoikis-related DEGs (ARDEGs), autophagy-related DEGs (AURDEGs), and pyroptosis-related DEGs (PRDEGs). Further scrutiny involved discerning disparities in these DEGs between AS patients and healthy controls, as well as disparities between male and female patients. Leveraging machine learning (ML) methodologies, we formulated disease prediction models employing cell death-related DEGs (CDRDEGs) and identified biomarkers intertwined with cell death in AS. Relative to healthy controls, a myriad of differentially expressed genes (DEGs) linked to cell death surfaced in AS patients. Among AS patients, 82 FRDEGs, 29 CRDEGs, 54 AURDEGs, 21 ARDEGs, and 74 PRDEGs were identified. In male AS patients, these numbers were 78, 33, 55, 24, and 94, respectively. Female AS patients exhibited 66, 41, 40, 17, and 82 DEGs in the corresponding categories. Additionally, 36 FRDEGs, 14 CRDEGs, 19 AURDEGs, 10 ARDEGs, and 36 PRDEGs exhibited differential expression between male and female AS patients. Employing machine learning techniques, LASSO, RF, and SVM-RFE were employed to discern key DEGs related to cell death (CDRDDEGs). The six pivotal CDRDDEGs in AS patients, healthy controls, were identified as CLIC4, BIRC2, MATK, PKN2, SLC25A5, and EDEM1. For male AS patients, the three crucial CDRDDEGs were EDEM1, MAP3K11, and TRIM21, whereas for female AS patients, COX7B, PEX2, and RHEB took precedence. Furthermore, the trio of DDX3X, CAPNS1, and TMSB4Y emerged as the key CDRDDEGs distinguishing between male and female AS patients. In the realm of immune correlation, the immune infiltration abundance in female patients mirrored that of healthy controls. Notably, key genes exhibited a positive correlation with T-cell CD4 memory activation when comparing male and female patient samples. This study engenders a more profound comprehension of the molecular underpinnings governing immune cell infiltration and cell death in ankylosing spondylitis (AS). Furthermore, the discernment of gender-specific disparities among AS patients underscores the clinical significance of these findings. By identifying DEGs associated with diverse cell death modalities, this study proffers invaluable insights into potential clinical targets for AS patients, taking cognizance of gender-specific nuances. The identification of gender-specific biological targets lays the groundwork for the development of tailored diagnostic and therapeutic strategies, heralding a pivotal step toward personalized care for AS patients.

The shared role of neutrophils in ankylosing spondylitis and ulcerative colitis.

This study aimed to analyze single-cell sequencing data to investigate immune cell interactions in ankylosing spondylitis (AS) and ulcerative colitis (UC). Vertebral bone marrow blood was collected from three AS patients for 10X single-cell sequencing. Analysis of single-cell data revealed distinct cell types in AS and UC patients. Cells significantly co-expressing immune cells (P < 0.05) were subjected to communication analysis. Overlapping genes of these co-expressing immune cells were subjected to GO and KEGG analyses. Key genes were identified using STRING and Cytoscape to assess their correlation with immune cell expression. The results showed the significance of neutrophils in both diseases (P < 0.01), with notable interactions identified through communication analysis. XBP1 emerged as a Hub gene for both diseases, with AUC values of 0.760 for AS and 0.933 for UC. Immunohistochemistry verified that the expression of XBP1 was significantly lower in the AS group and significantly greater in the UC group than in the control group (P < 0.01). This finding highlights the critical role of neutrophils in both AS and UC, suggesting the presence of shared immune response elements. The identification of XBP1 as a potential therapeutic target offers promising intervention avenues for both diseases.

Exploration of the combined role of immune checkpoints and immune cells in the diagnosis and treatment of ankylosing spondylitis: a preliminary study immune checkpoints in ankylosing spondylitis.

OBJECTIVE: Immune checkpoints have emerged as promising therapeutic targets for autoimmune diseases. However, the specific roles of immune checkpoints in the pathophysiology of ankylosing spondylitis (AS) remain unclear. METHODS: Hip ligament samples were obtained from two patient groups: those with AS and femoral head deformity, and those with femoral head necrosis but without AS, undergoing hip arthroplasty. Label-Free Quantification (LFQ) Protein Park Analysis was used to identify the protein composition of the ligaments. Peripheral blood samples of 104 AS patients from public database were used to validate the expression of key proteins. KEGG, GO, and GSVA were employed to explore potential pathways regulated by immune checkpoints in AS progression. xCell was used to calculate cell infiltration levels, LASSO regression was applied to select key cells, and the correlation between immune checkpoints and immune cells was analyzed. Drug sensitivity analysis was conducted to identify potential therapeutic drugs targeting immune checkpoints in AS. The expression of key genes was validated through immunohistochemistry (IHC). RESULTS: HLA-DMB and HLA-DPA1 were downregulated in the ligaments of AS and this has been validated through peripheral blood datasets and IHC. Significant differences in expression were observed in CD8 + Tcm, CD8 + T cells, CD8 + Tem, osteoblasts, Th1 cells, and CD8 + naive T cells in AS. The infiltration levels of CD8 + Tcm and CD8 + naive T cells were significantly positively correlated with the expression levels of HLA-DMB and HLA-DPA1. Immune cell selection using LASSO regression showed good predictive ability for AS, with AUC values of 0.98, 0.81, and 0.75 for the three prediction models, respectively. Furthermore, this study found that HLA-DMB and HLA-DPA1 are involved in Th17 cell differentiation, and both Th17 cell differentiation and the NF-kappa B signaling pathway are activated in the AS group. Drug sensitivity analysis showed that AS patients are more sensitive to drugs such as doramapimod and GSK269962A. CONCLUSION: Immune checkpoints and immune cells could serve as avenues for exploring diagnostic and therapeutic strategies for AS.

Exploring the Pathogenesis of Spondylarthritis beyond HLA-B27: A Descriptive Review.

Spondylarthritis (SpA) is a chronic inflammatory condition that encompasses damage to the axial or peripheral skeleton, accompanied by specific extra-articular symptoms. Within this group, Ankylosing Spondylitis stands out as the hallmark member. Although the heritability of Ankylosing Spondylitis is estimated to be over 95%, only a portion of the heritability has been explained, with HLA-B27 accounting for 20.1% of it; therefore, ongoing research endeavors are currently concentrated on investigating the potential participation of different entities in the development of the disease. Genome-wide association studies have led to significant advances in our understanding of the genetics of SpA. In this descriptive review, we delve into the pathogenesis of Spondylarthritis beyond HLA-B27. We summarize the latest research on the potential participation of various entities in the development of the disease, including other genetic loci, immune dysregulation, microbiota, and environmental factors. The multifactorial nature of SpA and the complex interplay of genetic, immunological, and environmental factors are being increasingly recognized; therefore, it is of paramount importance to consider a holistic approach to comprehend the pathogenesis of SpA in order to identify novel therapeutic targets.

Sex dimorphism of IL-17-secreting peripheral blood mononuclear cells in ankylosing spondylitis based on bioinformatics analysis and machine learning.

BACKGROUND: Ankylosing spondylitis (AS) with radiographic damage is more prevalent in men than in women. IL-17, which is mainly secreted from peripheral blood mononuclear cells (PBMCs), plays an important role in the development of AS. Its expression is different between male and female. However, it is still unclear whether sex dimorphism of IL-17 contribute to sex differences in AS. METHODS: GSE221786, GSE73754, GSE25101, GSE181364 and GSE205812 datasets were collected from the Gene Expression Omnibus (GEO) database. Differential expressed genes (DEGs) were analyzed with the Gene Set Enrichment Analysis (GSEA), Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) methods. CIBERSORTx and EcoTyper algorithms were used for immune infiltration analyses. Machine learning based on the XGBoost algorithm model was used to identify the impact of DEGs. The Connectivity Map (CMAP) database was used as a drug discovery tool for exploring potential drugs based on the DEGs. RESULTS: According to immune infiltration analyses, T cells accounted for the largest proportion of IL-17-secreting PBMCs, and KEGG analyses suggested an enhanced activation of mast cells among male AS patients, whereas the expression of TNF was higher in female AS patients. Other signaling pathways, including those involving metastasis-associated 1 family member 3 (MAT3) or proteasome, were found to be more activated in male AS patients. Regarding metabolic patterns, oxidative phosphorylation pathways and lipid oxidation were significantly upregulated in male AS patients. In XGBoost algorithm model, DEGs including METRN and TMC4 played important roles in the disease process. we integrated the CMAP database for systematic analyses of polypharmacology and drug repurposing, which indicated that atorvastatin, famciclocir, ATN-161 and taselisib may be applicable to the treatment of AS. CONCLUSIONS: We analyzed the sex dimorphism of IL-17-secreting PBMCs in AS. The results showed that mast cell activation was stronger in males, while the expression of TNF was higher in females. In addition, through machine learning and the CMAP database, we found that genes such as METRN and TMC4 may promote the development of AS, and drugs such as atorvastatin potentially could be used for AS treatment.

Research progress on Hippo signaling pathway effector molecules in rheumatic immune system diseases. / Hippoä¿¡å·é€šè·¯æ•ˆåº”åˆ†å­åœ¨é£Žæ¹¿å ç–«ç³»ç»Ÿç–¾ç— ä¸­çš„ä½œç”¨ç ”ç©¶è¿›å±•.

The core components of the Hippo signaling pathway encompass upstream regulatory molecules, core kinase cascade complexes, and downstream transcriptional regulation complexes. This pathway modulates cellular behaviors by influencing the effector molecules of its core components and plays a pivotal role in immune regulation. Effector molecules,such as Yes-associated protein (YAP), transcriptional coactivator with PDZ-binding motif (TAZ), transcriptional enhanced associate domain transcriptional factor (TEAD), monopolar spindle-one binder (MOB1), large tumor suppressor (LATS), can stimulate fibroblast-like synovial cell migration and invasion in rheumatoid arthritis, regulate osteoarthritis disease progression, promote pathological new bone formation in ankylosing spondylitis, sustain submandibular gland development while delaying Sjogren's syndrome progression, mediate alpha-smooth muscle actin in systemic sclerosis, and refine the regulation of target genes associated with pulmonary fibrosis. This article provides an overview of the regulatory mechanisms involving Hippo signaling pathway-related effector molecules in the pathogenesis and progression of rheumatic immune system diseases, to serve as a reference for exploring novel therapeutic targets of rheumatic immune system diseases.

A short review on deciphering Vyadhikshamatva: insights from HLA-B27-ankylosing spondylitis relation.

OBJECTIVES: Various aspects of the concept of Vyadhikshamatva have been thoroughly explored, highlighting its profound significance in resisting disease manifestation, particularly in the context of Ankylosing spondylitis. Investigated the relationship between HLA-B27 and Ankylosing spondylitis (AS) by examining current knowledge and hypotheses Furthermore, efforts were made to portray the influence of prakruti (constitution) and balam (strength) on disease manifestation and progression. METHODS: Ayurvedic literature along with contemporary research works was analyzed for correlating various aspects like vyadhikshamatva,oja (The final essence of all body elements), and balam along with their influence on the defensive mechanism of the body. A thorough literature search was conducted to explore the strong association between HLA-B27 and AS by examining various hypotheses like the Arthritogenic peptide hypothesis, the Misfolding hypothesis, the Surface Homodimer hypothesis, and the ß2 microglobulin hypothesis that attempts to explain the pathogenic role of HLA-B27 in AS. Alongside classical Ayurvedic texts, databases like PubMed and Scopus were searched using keywords such as Immunity, Ankylosing spondylitis, Vyadhikshamatva, HLA-B27, Balam, and Autoimmune disorder with the help of Boolean operators. RESULTS: The review highlighted the critical role of Vyadhikshamatva in disease prevention, particularly in influencing the manifestation of conditions like AS despite genetic predisposition (HLA-B27). Further, the understanding of the Ayurvedic concepts can clearly explain the conflict that has arisen in the determination of the positive HLAB27 gene in Ankylosing Spondylitis as a definite diagnosing criteria. CONCLUSIONS: This comprehensive understanding will uplift the need for personalized medicine in disease management. Further research must be needed to understand the interaction between genetic factors (HLAb27), individual constitution, and their vyadikshamatva.

Genetic variability of three common NK and γδ T cell receptor genes (FCγ3R, NCR3, and DNAM-1) and their role in Polish patients with rheumatoid arthritis and ankylosing spondylitis.

Various lymphocyte subpopulations, including NK cells as well as γδ T cells, have been considered an important element in the pathogenesis of autoimmune, inflammatory, rheumatic diseases, such as rheumatoid arthritis (RA) and ankylosing spondylitis (AS). The aim of this study was to assess the potential role of polymorphic variations in the genes coding for three NK and γδ T cell receptors: NCR3, FCγR3A, and DNAM-1 (rs1052248, rs396991, and rs763361, respectively) in the disease susceptibility and the efficacy of treatment with TNF inhibitors. The study included 461 patients with RA, 168 patients with AS, and 235 voluntary blood donors as controls. The NCR3 rs1052248 AA homozygosity prevailed in RA in patients lacking rheumatoid factor (p = 0.044) as well as in those who manifested the disease at a younger age (p = 0.005) and had higher CRP levels after 12 weeks of anti-TNF therapy (p = 0.021). The FCγR3A rs396991 polymorphism was associated with pain visual analogue scale (VAS) values before the initiation of anti-TNF treatment. Lower VAS values were observed in the GG homozygous RA patients (p = 0.024) and in AS patients with the TT genotype (p = 0.012). Moreover, AS heterozygous patients with the TG genotype presented higher CRP levels in the 12th week of anti-TNF treatment (p = 0.021). The findings suggest that the NCR3 rs1052248 AA homozygosity may have an adverse effect on RA, while the T allele potentially plays a protective role in the development of AS. Moreover, the rs1052248 T allele and TT genotype appear to have a favorable impact on the response to anti-TNF therapy in RA patients.

scRNA + TCR-seq revealed the dual TCR pTh17 and Treg T cells involvement in autoimmune response in ankylosing spondylitis.

OBJECTIVE: Th17 and Treg play important roles in AS, but their single and dual TCR pairing types, ratios, and CDR3 characteristics remain unknown. METHODS: Single-cell RNA + TCR-seq results from six AS patients were used to cluster T-cell subpopulations and analyze the single and dual TCR T cell ratio, diversity/clonality/overlap of CDR3, and expression of transcription factors. RESULTS: 1. AS patients have about 10% of dual TCR T cells, and SFMC have decreased diversity CDR3 libraries and significant clonal proliferation compared to PBMC. 2. Dual TCR ratio: memory T > naive T; pTh 17 > Th17; Treg /Th17/Th1/EM significantly higher than naive CD4 + T/CM, Pathogenic Th17 cells contain clonally proliferating single TCR and dual TCR cells. 3. The expression of single TCR and dual TCR transcription factors of each T cell subpopulation was basically the same, but there was differential expression of characteristic transcription factors, e.g. Foxp3, CTLA4, STAT5B, IL10RB, LAG3 in dual TCR Treg was higher than that of single TCR Treg; TNFSF10/12, TNFRSF4/14, CCL5, KLRB1 in dual TCR pTh17 were significantly higher than those in single TCR pTh17. 4. Between naive CD4 + T, pTh17, Th1 and Treg, there are partially identity identical tcr paired cells. CONCLUSIONS: The high proportion of dual TCR T cells such as pTh17 and Treg in AS and the high expression of some transcription factors suggested a close association with self-response in AS; The overlap of CDR3 between Th1, Th17,pTh17, and Treg in AS suggested that the subpopulations may be differentiated from each other to regulate the inflammatory homeostasis and progression.

Prognostic models of drug-induced neutralizing antibody formation in patients with rheumatoid arthritis, psoriatic arthritis, ankylosing spondylitis treated with TNF-α blockersockers.

AIM: This study aimed to construct prognostic mathematical models utilizing multifactorial regression analysis to assess the risk of developing drug-induced neutralizing antibodies in patients with rheumatoid arthritis, psoriatic arthritis, and ankylosing spondylitis treated with tumor necrosis factor alpha blockers.

Gut microbiome and metabolome to discover pathogenic bacteria and probiotics in ankylosing spondylitis.

Objective: Previous research has partially revealed distinct gut microbiota in ankylosing spondylitis (AS). In this study, we performed non-targeted fecal metabolomics in AS in order to discover the microbiome-metabolome interface in AS. Based on prospective cohort studies, we further explored the impact of the tumor necrosis factor inhibitor (TNFi) on the gut microbiota and metabolites in AS. Methods: To further understand the gut microbiota and metabolites in AS, along with the influence of TNFi, we initiated a prospective cohort study. Fecal samples were collected from 29 patients with AS before and after TNFi therapy and 31 healthy controls. Metagenomic and metabolomic experiments were performed on the fecal samples; moreover, validation experiments were conducted based on the association between the microbiota and metabolites. Results: A total of 7,703 species were annotated using the metagenomic sequencing system and by profiling the microbial community taxonomic composition, while 50,046 metabolites were identified using metabolite profiling. Differential microbials and metabolites were discovered between patients with AS and healthy controls. Moreover, TNFi was confirmed to partially restore the gut microbiota and the metabolites. Multi-omics analysis of the microbiota and metabolites was performed to determine the associations between the differential microbes and metabolites, identifying compounds such as oxypurinol and biotin, which were correlated with the inhibition of the pathogenic bacteria Ruminococcus gnavus and the promotion of the probiotic bacteria Bacteroides uniformis. Through experimental studies, the relationship between microbes and metabolites was further confirmed, and the impact of these two types of microbes on the enterocytes and the inflammatory cytokine interleukin-18 (IL-18) was explored. Conclusion: In summary, multi-omics exploration elucidated the impact of TNFi on the gut microbiota and metabolites and proposed a novel therapeutic perspective: supplementation of compounds to inhibit potential pathogenic bacteria and to promote potential probiotics, therefore controlling inflammation in AS.

Investigating the Influence of ANTXR2 Gene Mutations on Protective Antigen Binding for Heightened Anthrax Resistance.

Bacillus anthracis is the bacterium responsible for causing the zoonotic disease called anthrax. The disease presents itself in different forms like gastrointestinal, inhalation, and cutaneous. Bacterial spores are tremendously adaptable, can persist for extended periods and occasionally endanger human health. The Anthrax Toxin Receptor-2 (ANTXR2) gene acts as membrane receptor and facilitates the entry of the anthrax toxin into host cells. Additionally, mutations in the ANTXR2 gene have been linked to various autoimmune diseases, including Hyaline Fibromatosis Syndrome (HFS), Ankylosing Spondylitis (AS), Juvenile Hyaline Fibromatosis (JHF), and Infantile Systemic Hyalinosis (ISH). This study delves into the genetic landscape of ANTXR2, aiming to comprehend its associations with diverse disorders, elucidate the impacts of its mutations, and pinpoint minimal non-pathogenic mutations capable of reducing the binding affinity of the ANTXR2 gene with the protective antigen. Recognizing the pivotal role of single-nucleotide polymorphisms (SNPs) in shaping genetic diversity, we conducted computational analyses to discern highly deleterious and tolerated non-synonymous SNPs (nsSNPs) in the ANTXR2 gene. The Mutpred2 server determined that the Arg465Trp alteration in the ANTXR2 gene leads to altered DNA binding (p = 0.22) with a probability of a deleterious mutation of 0.808; notably, among the identified deleterious SNPs, rs368288611 (Arg465Trp) stands out due to its significant impact on altering the DNA-binding ability of ANTXR2. We propose these SNPs as potential candidates for hypertension linked to the ANTXR2 gene, which is implicated in blood pressure regulation. Noteworthy among the tolerated substitutions is rs200536829 (Ala33Ser), recognized as less pathogenic; this highlights its potential as a valuable biomarker, potentially reducing side effects on the host while also reducing binding with the protective antigen protein. Investigating these SNPs holds the potential to correlate with several autoimmune disorders and mitigate the impact of anthrax disease in humans.

Angiogenesis-related immune response may be the prelude to the syndesmophyte formation in Ankylosing spondylitis.

BACKGROUND: Ankylosing spondylitis (AS) is a chronic autoimmune arthritis that mainly affects spine joints. To date, the pathogenesis of AS remains unclear, although immune cells and innate immune response cytokines have been suggested to be crucial players. METHODS: By adopting a single-cell RNA sequencing approach in the AS cynomolgus model, we profiled and characterized PBMC proportions along disease progression. RESULTS: Here, our primary focus was on the activation of an immune cascade-initiating lymphocyte subtype known as CD4+CXCR5+ T follicular helper (Tfh) cells. These Tfhs demonstrated a localized residence in AS bone lesion as an ectopic lymphoid structure. Moreover, Tfhs would serve as an upstream initiator for a pro-angiogenic cascade. Then, an expansion in CD14+ monocytes and DC cells subsets resulted in enhanced expression of angiogenesis genes in these AS cynomolgus monkeys. With a confirmed higher abundance of TNF-α accompanying H-type vascular invasion in the osteophytic region, pronounced expansion of Tfhs at such lesion site signaling for monocytes and DCs intrusion is considered as the prelude to the characteristic angiogenic bony outgrowth in AS known as syndesmophytes. CONCLUSIONS: We explored the intimate relationship between local inflammation and bone formation in AS from the perspective of nascent vascularisation. Hence, our study lays the foundation for elucidating a unified AS pathogenesis through the immune-angiogenesis-osteogenesis axis.

miRNAs dysregulation in ankylosing spondylitis: A review of implications for disease mechanisms, and diagnostic markers.

Epigenetic processes, including non-coding RNA, histone modifications, and DNA methylation, play a vital role in connecting the environment to the development of a disorder, especially when there is a favorable genetic background. Ankylosing Spondylitis (AS) is a chronic type of spinal arthritis that highlights the significance of epigenetics in diseases related to autoimmunity and inflammation. MicroRNAs (miRNAs) are small non-coding RNAs that are involved in both normal and aberrant pathological and physiological gene expression. This study focuses on the pathophysiological pathways to clarify the role of miRNAs in AS. We have conducted a thorough investigation of the involvement of miRNAs in several processes, including inflammation, the production of new bone, T-cell activity, and the regulation of pathways such as BMP, Wnt, and TGFß signaling. Undoubtedly, miRNAs play a crucial role in enhancing our comprehension of the pathophysiology of AS, and their promise as a therapeutic strategy is quickly expanding.

Causal relationship between the immune cells and ankylosing spondylitis: univariable, bidirectional, and multivariable Mendelian randomization.

Background: Ankylosing spondylitis (AS) is an autoimmune disease that affects millions of individuals. Immune cells have been recognized as having a crucial role in the pathogenesis of AS. However, their relationship has not been fully explored. Methods: We chose to employ Mendelian randomization (MR) to investigate the potential correlation between immune cells and AS. We sourced the data on immune cells from the latest genome-wide association studies (GWASs). We obtained data on AS from the FinnGen consortium. Our comprehensive univariable MR analysis covered 731 immune cells to explore its potential causal relationship with AS. The primary analysis method was inverse-variance weighted (IVW). Additionally, we used Cochran's Q test and the MR-Egger intercept test to assess the presence of pleiotropy and heterogeneity. We examined whether our results could be influenced by individual single-nucleotide polymorphisms (SNPs) using the leave-one-out test. We conducted a bidirectional MR to investigate the reverse relationship. We also applied multivariable MR to decrease the potential influence between the immune cells. Results: Overall, our univariable MR analysis revealed eight immune cells associated with AS. Among these, four immune cells contributed to an increased risk of AS, while four immune cells were identified as protective factors for AS. However, the Bonferroni test confirmed only one risk factor and one protective factor with a significance level of p < 6.84E-05. CD8 on effector memory CD8+ T cell could increase the risk of AS (p: 1.2302E-05, OR: 2.9871, 95%CI: 1.8289-4.8786). HLA DR on CD33dim HLA DR+ CD11b+ could decrease the risk of AS (p: 1.2301E-06, OR: 0.5446, 95%CI: 0.4260-0.6962). We also identified a bidirectional relationship between CD4 on CD39+ activated CD4 regulatory T cells and AS utilizing the bidirectional MR. To address potential confounding among immune cells, we employed multivariable MR analysis, which revealed that only one immune cell had an independent effect on AS. HLA DR on CD33dim HLA DR+ CD11b+ could decrease the risk of AS (p: 2.113E-06, OR: 0.0.5423, 95%CI: 0.4210-0.6983). Our findings were consistently stable and reliable. Conclusions: Our findings indicated a potential link between immune cells and AS, which could provide a new idea for future research. Nevertheless, the specific underlying mechanisms require further exploration.

IL-17-producing cells in ankylosing spondylitis patients show gender-based differences in gene expression.

OBJECTIVES: Gender has been shown to impact disease expression in ankylosing spondylitis (AS) and Th17 cells play a key role in AS pathogenesis. To better understand what Th17-associated immune pathways are different between men and women, we compared the transcriptome of IL-17-enriched peripheral blood mononuclear cells (PBMCs) in male and female AS patients, with a particular focus on inflammatory cytokine genes. METHODS: PBMCs were collected from 10 female and 11 male AS patients at the Clinical Research Unit of MetroHealth Medical Center. IL-17-enriched PBMCs were isolated and stimulated with CytoStim. RNA-sequencing (RNA-seq) was performed on the samples, and the data were analysed using iPathwayGuide. Inflammatory markers and genes related to Th17 differentiation and function were identified based on previous studies. RESULTS: RNA-seq identified 12,893 genes with 2,851 genes with p-values <0.05 with distinct patterns of gene expression between male and female AS patients. TGF-ß, PGE2, and S100 proteins were significantly upregulated in males. Levels of IL-12B, a Th17 inducer, were lower in males compared to females. Additionally, receptors of IL-6, 12, 23, TGF-ß, and PGE2 were downregulated in males, except for IL-17RC, which was upregulated. Genes involved in Th17 differentiation showed differential expression between genders, with elevated expression of BATF, SOCS1, NKD2, and ARID5A in men and decreased expression of FOXO1. CONCLUSIONS: Transcriptomic analysis revealed that male AS patients exhibit distinct expression patterns of IL-17 pro-inflammatory genes, which may contribute to the phenotypic differences observed between genders in AS.

Comprehensive Association Analyses of Extraintestinal Manifestations in Inflammatory Bowel Disease.

BACKGROUND & AIMS: Patients with inflammatory bowel disease (IBD) frequently develop extraintestinal manifestations (EIMs) that contribute substantially to morbidity. We assembled the largest multicohort data set to date to investigate the clinical, serologic, and genetic factors associated with EIM complications in IBD. METHODS: Data were available in 12,083 unrelated European ancestry IBD cases with presence or absence of EIMs (eg, ankylosing spondylitis [ankylosing spondylitis and sacroiliitis], primary sclerosing cholangitis [PSC], peripheral arthritis, and skin and ocular manifestations) across 4 cohorts (Cedars-Sinai Medical Center, National Institute for Diabetes and Digestive and Kidney Diseases IBD Genetics Consortium, Sinai Helmsley Alliance for Research Excellence Consortium, and Risk Stratification and Identification of Immunogenetic and Microbial Markers of Rapid Disease Progression in Children with Crohn's Disease cohort). Clinical and serologic parameters were analyzed by means of univariable and multivariable regression analyses using a mixed-effects model. Within-case logistic regression was performed to assess genetic associations. RESULTS: Most EIMs occurred more commonly in female subjects (overall EIM: P = 9.0E-05, odds ratio [OR], 1.2; 95% CI, 1.1-1.4), with CD (especially colonic disease location; P = 9.8E-09, OR, 1.7; 95% CI, 1.4-2.0), and in subjects who required surgery (both CD and UC; P = 3.6E-19, OR, 1.7; 95% CI, 1.5-1.9). Smoking increased risk of EIMs except for PSC, where there was a "protective" effect. Multiple serologic associations were observed, including with PSC (anti-nuclear cytoplasmic antibody; IgG and IgA, anti-Saccharomyces cerevisiae antibodies; and anti-flagellin) and any EIM (anti-nuclear cytoplasmic antibody; IgG and IgA, anti-Saccharomyces cerevisiae antibodies; and anti-Pseudomonas fluorescens-associated sequence). We identified genome-wide significant associations within major histocompatibility complex (ankylosing spondylitis and sacroiliitis, P = 1.4E-15; OR, 2.5; 95% CI, 2.0-3.1; PSC, P = 2.7E-10; OR, 2.8; 95% CI, 2.0-3.8; ocular, P = 2E-08, OR, 3.6; 95% CI, 2.3-5.6; and overall EIM, P = 8.4E-09; OR, 2.2; 95% CI, 1.7-2.9) and CPEB4 (skin, P = 2.7E-08; OR, 1.5; 95% CI, 1.3-1.8). Genetic associations implicated tumor necrosis factor, JAK-STAT, and IL6 as potential targets for EIMs. Contrary to previous reports, only 2% of our subjects had multiple EIMs and most co-occurrences were negatively correlated. CONCLUSIONS: We have identified demographic, clinical, and genetic associations with EIMs that revealed underlying mechanisms and implicated novel and existing drug targets-important steps toward a more personalized approach to IBD management.

Serum biomarkers and their relationship to axial spondyloarthritis associated with inflammatory bowel diseases.

Spondyloarthritis (SpA) constitute a group of chronic inflammatory immune-mediated rheumatic diseases characterized by genetic, clinical, and radiological features. Recent efforts have concentrated on identifying biomarkers linked to axial SpA associated with inflammatory bowel disease (IBD), offering predictive insights into disease onset, activity, and progression. Genetically, the significance of the HLA-B27 antigen is notably diminished in ankylosing spondylitis (AS) associated with IBD, but is heightened in concurrent sacroiliitis. Similarly, certain polymorphisms of endoplasmic reticulum aminopeptidase (ERAP-1) appear to be involved. Carriage of variant NOD2/CARD15 polymorphisms has been demonstrated to correlate with the risk of subclinical intestinal inflammation in AS. Biomarkers indicative of pro-inflammatory activity, including C-reactive protein (CRP) along with erythrocyte sedimentation rate (ESR), are among the consistent predictive biomarkers of disease progression. Nevertheless, these markers are not without limitations and exhibit relatively low sensitivity. Other promising markers encompass IL-6, serum calprotectin (s-CLP), serum amyloid (SAA), as well as biomarkers regulating bone formation such as metalloproteinase-3 (MMP-3) and Dickkopf-related protein 1 (DKK-1). Additional candidate indicators of structural changes in SpA patients include matrix metalloproteinase-3 (MMP-3), vascular endothelial growth factor (VEGF), tenascin C (TNC), and CD74 IgG. Fecal caprotein (f-CLP) levels over long-term follow-up of AS patients have demonstrated predictive value in anticipating the development of IBD. Serologic antibodies characteristic of IBD (ASCA, ANCA) have also been compared; however, results exhibit variability. In this review, we will focus on biomarkers associated with both axial SpA and idiopathic intestinal inflammation, notably enteropathic spondyloarthritis.

Autoimmunity to the modified self.

Protein posttranslational modifications can break tolerance to the self-proteome.

Autoimmunity-associated T cell receptors recognize HLA-B*27-bound peptides.

Human leucocyte antigen B*27 (HLA-B*27) is strongly associated with inflammatory diseases of the spine and pelvis (for example, ankylosing spondylitis (AS)) and the eye (that is, acute anterior uveitis (AAU))1. How HLA-B*27 facilitates disease remains unknown, but one possible mechanism could involve presentation of pathogenic peptides to CD8+ T cells. Here we isolated orphan T cell receptors (TCRs) expressing a disease-associated public ß-chain variable region-complementary-determining region 3ß (BV9-CDR3ß) motif2-4 from blood and synovial fluid T cells from individuals with AS and from the eye in individuals with AAU. These TCRs showed consistent α-chain variable region (AV21) chain pairing and were clonally expanded in the joint and eye. We used HLA-B*27:05 yeast display peptide libraries to identify shared self-peptides and microbial peptides that activated the AS- and AAU-derived TCRs. Structural analysis revealed that TCR cross-reactivity for peptide-MHC was rooted in a shared binding motif present in both self-antigens and microbial antigens that engages the BV9-CDR3ß TCRs. These findings support the hypothesis that microbial antigens and self-antigens could play a pathogenic role in HLA-B*27-associated disease.