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

The role of bDMARDs in the prevention and treatment of inflammatory-related comorbidities in Psoriatic Arthritis

INTRODUCTION

Psoriatic arthritis (PsA) is an immune-inflammatory disease that affects both joints and entheses, and with diverse extra-articular manifestations (psoriasis, inflammatory bowel disease (IBD), and uveitis). A wide range of comorbid conditions, including cardiovascular diseases, obesity, metabolic syndrome (MetS), nonalcoholic fatty liver disease (NAFLD), mental health disorders (depression/anxiety), and osteoporosis are highly prevalent in course of PsA.Biological DMARDs (bDMARD), including TNF-inhibitors (TNFi), Interleukin (IL-17i) and IL-23i represent the cornerstone of the management of active disease. The use of these therapies obviously requires considering comorbidities presence, safety aspects and contraindications.

AREAS COVERED

The aim of this review is to describe the inflammatory mechanisms behind PsA comorbidities, and the role of bDMARDs in the prevention and treatment of these conditions in course of PsA.

EXPERT OPINION

Tailoring therapeutic strategies to the individual characteristics of each PsA patient can be an effective approach to manage comorbidities, maximizing the efficacy of bDMARDs, and reducing the incidence of AEs. Identifying targets within disease pathways can guide research into therapeutics that address both PsA and comorbidities simultaneously, but more studies are advocated for clarifying the potential prevention and management of bDMARDs used for PsA.

Functional significance of DNA methylation: epigenetic insights into Sjögren's syndrome

Sjögren's syndrome (SjS) is a systemic, highly diverse, and chronic autoimmune disease with a significant global prevalence. It is a complex condition that requires careful management and monitoring. Recent research indicates that epigenetic mechanisms contribute to the pathophysiology of SjS by modulating gene expression and genome stability. DNA methylation, a form of epigenetic modification, is the fundamental mechanism that modifies the expression of various genes by modifying the transcriptional availability of regulatory regions within the genome. In general, adding a methyl group to DNA is linked with the inhibition of genes because it changes the chromatin structure. DNA methylation changes the fate of multiple immune cells, such as it leads to the transition of naïve lymphocytes to effector lymphocytes. A lack of central epigenetic enzymes frequently results in abnormal immune activation. Alterations in epigenetic modifications within immune cells or salivary gland epithelial cells are frequently detected during the pathogenesis of SjS, representing a robust association with autoimmune responses. The analysis of genome methylation is a beneficial tool for establishing connections between epigenetic changes within different cell types and their association with SjS. In various studies related to SjS, most differentially methylated regions are in the human leukocyte antigen (HLA) locus. Notably, the demethylation of various sites in the genome is often observed in SjS patients. The most strongly linked differentially methylated regions in SjS patients are found within genes regulated by type I interferon. This demethylation process is partly related to B-cell infiltration and disease progression. In addition, DNA demethylation of the runt-related transcription factor (RUNX1) gene, lymphotoxin-α (LTA), and myxovirus resistance protein A (MxA) is associated with SjS. It may assist the early diagnosis of SjS by serving as a potential biomarker. Therefore, this review offers a detailed insight into the function of DNA methylation in SjS and helps researchers to identify potential biomarkers in diagnosis, prognosis, and therapeutic targets.

Impact of biological therapy in reducing the risk of arthritis development in inflammatory bowel diseases

OBJECTIVE

Evaluate spondyloarthritis (SpA) incidence in inflammatory bowel diseases (IBD) between patients treated with biological disease-modifying antirheumatic drugs (bDMARDs) and conventional DMARDs (cDMARDs) and define risk factors associated with SpA development.

METHODS

Retrospective cohort study was conducted on patients with Crohn's disease (CD) or ulcerative colitis (UC) and divided into two cohorts: cDMARDs or bDMARDs/targeted synthetic (ts) DMARDs treated patients. Rheumatological assessment was performed in patients presenting musculoskeletal symptoms. Multivariate analysis and Kaplan-Meier curves were used to evaluate the adjusted SpA risk development.

RESULTS

507 patients were included in the study. 176 patients with CD received bDMARDs, 112 cDMARDs and 106 new SpA diagnosies were formulated. Females (OR 1.7 (95% CI 1.1 to 3), adjusted p=0.04), non-stricturing/non-penetrating phenotype (OR 2 (95% CI 1.1 to 3.4), adjusted p=0.01), psoriasis (OR 2.1 (95% CI 1 to 4.6), adjusted p=0.04) and non-infectious uveitis (OR 6.8 (95% CI 1.4 to 33.4), adjusted p=0.01) were associated with increased SpA risk development, while bDMARDs usage was protective (OR 0.4 (95% CI 0.2 to 0.8), adjusted p=0.01), statistically higher than cDMARDs throughout the entire follow-up (effect size 0.47). 98 patients with UC received b-tsDMARDs, 121 cDMARDs and 56 new SpA diagnoses were formulated. Females (OR 2.1 (95% CI 1 to 4.3), adjusted p=0.02) and psoriasis (OR 2.7 (95% CI 1 to 6.8), adjusted p=0.03) were associated with increased SpA risk development, while bDMARDs were protective for SpA development for up to 12 months of treatment compared with cDMARDs (p=0.03).

CONCLUSIONS

bDMARDs treatment had an impact in reducing SpA development and clinical associated risk factors to transition from IBD to IBD-SpA emerged.

HLA-B*27 and Ankylosing Spondylitis: 50 Years of Insights and Discoveries

PURPOSE OF REVIEW

To commemorate the 50th anniversary of the groundbreaking discovery of a remarkably strong association between HLA-B*27 and ankylosing spondylitis (AS).

RECENT FINDINGS

In addition to HLA-B*27, more than 116 other recognized genetic risk variants have been identified, while epigenetic factors largely remain unexplored in this context. Among patients with AS who carry the HLA-B*27 gene, clonally expanded CD8 + T cells can be found in their bloodstream and within inflamed tissues. Moreover, the α and β chain motifs of these T-cell receptors demonstrate a distinct affinity for certain self- and microbial-derived peptides, leading to an autoimmune response that ultimately results in the onset of the disease. These distinctive peptide-binding and presentation characteristics are a hallmark of the disease-associated HLA-B*27:05 subtype but are absent in HLA-B*27:09, a subtype not associated with the disease, differing by only a single amino acid. This discovery represents a significant advancement in unraveling the 50-year-old puzzle of how HLA-B*27 contributes to the development of AS. These findings will significantly accelerate the process of identifying peptides, both self- and microbial-derived, that instigate autoimmunity. This, in return, will pave the way for the development of more accurate and effective targeted treatments. Moreover, the discovery of improved biomarkers, in conjunction with the emerging technology of electric field molecular fingerprinting, has the potential to greatly bolster early diagnosis capabilities. A very recently published groundbreak paper underscores the remarkable effectiveness of targeting and eliminating disease-causing T cells in a HLA-B*27 patients with AS. This pivotal advancement not only signifies a paradigm shift but also bolsters the potential for preventing the disease in individuals carrying high-risk genetic variants.

Shedding Light on the Role of ERAP1 in Axial Spondyloarthritis

Spondyloarthritis (SpA) is a multifactorial chronic inflammatory disease affecting the axial skeleton (axSpA) and/or peripheral joints (p-SpA) and entheses. The disease's pathogenesis depends on genetic, immunological, mechanical, and environmental factors. Endoplasmic reticulum aminopeptidase 1 (ERAP1) is a multifunctional enzyme that shapes the peptide repertoire presented by major histocompatibility complex (MHC) class I molecules. Genome-wide association studies (GWAS) have identified different single nucleotide polymorphisms (SNPs) in ERAP1 that are associated with several autoimmune diseases, including axSpA. Therefore, a deeper understanding of the ERAP1 role in axSpA could make it a potential therapeutic target for this disease and offer greater insight into its impact on the immune system. Here, we review the biological functions and structure of ERAP1, discuss ERAP1 polymorphisms and their association with axSpA, highlight the interaction between ERAP1 and human leukocyte antigen (HLA)-B27, and review the association between ERAP1 SNPs and axSpA clinical parameters.