Sex-specific analysis in Behçet's disease reveals higher genetic risk in male patients

Proteomic Profiles of Neutrophils from Behcet's Uveitis Patients and their Sex Differences

Behcet's uveitis (BU) is one of the most vision-threatening uveitis entities with male-biased incidence and severity. Neutrophil dysfunction has been implicated in the pathogenesis of this disease. However, their proteomic changes are not completely understood. We performed proteomic analysis on peripheral neutrophils from patients with active BU and identified 82 up-regulated and 516 down-regulated differentially expressed proteins (DEPs) compared to healthy controls (HCs). We further performed functional analysis on these DEPs and found that the pathway involved in neutrophil extracellular trap formation was activated, whereas nucleotide metabolism and apoptosis were suppressed. Compared with female patients, male patients presented enhanced pathways associated neutrophil-mediated inflammatory responses and suppressed apoptosis. Additionally, integrative analysis of proteomic profiles and single-cell RNA sequencing (scRNA-seq) data revealed that these sex differences might be related to the enhanced inflammatory response in primed inflammatory and inflammatory neutrophils as well as deficiencies in apoptosis and nucleotide metabolism in ROS-responsive neutrophils. Collectively, our data revealed the proteomic profiles of neutrophils from patients with BU, and their functional changes may play crucial roles in the pathogenesis of this disease and its sex differences.

Omics studies in Behçet's disease

PURPOSE OF REVIEW

In this review, we aimed to highlight recent findings from "-omics" studies in Behçet's disease.

RECENT FINDINGS

Recent genomic studies in Behçet's disease identified possible risk loci associated with Behçet's disease related uveitis, neurologic involvement and gastrointestinal involvement. Additionally, sex-specific genetic effects were determined in Behçet's disease. Transcriptomic analyses of immune cells in Behçet's disease revealed that key inflammatory pathways such as NF-κB and MAPK have roles in Behçet's disease pathogenesis. Proteomic studies have highlighted the role of immune cell derived extracellular vesicles and identified potential biomarkers for vascular involvement and examined HLA I-bound immunopeptidomes. Metabolomics studies are still limited, but recent research has pointed to alterations in fatty acid metabolism and lipid profiles in Behçet's disease patient.

SUMMARY

Omics studies have gained importance in the field of Behçet's disease through the generation of large data sets and efforts to extend their application are intensifying. These studies can provide opportunities for understanding Behçet's disease pathogenesis when they lead to testable hypotheses. Current challenges include the choice of appropriately homogeneous patient and control groups, effective data management and sharing, high cost and a rapidly increasing gap between the wealth of observational data generated and the relative paucity of controlled experimental efforts that could lead to mechanistic understanding.

HLA diversity unveils susceptibility and organ-specific occurrence of second primary cancers: a prospective cohort study

BACKGROUND

Up to 17% of cancer survivors have been reported to develop second primary cancers (SPC), which cause significant physical and economic distress and often complicate clinical decision-making. However, understanding of SPC remains limited and superficial. Human leukocyte antigen (HLA) is characterized by its polymorphism and has been associated with various diseases. This study aims to explore the role of HLA diversity in SPC incidence.

METHODS

We analyzed a cohort of 47,550 cancer patients from the UK Biobank. SNP-derived HLA alleles were used and SPC-related HLA alleles were identified using logistic regression, followed by stepwise filtering based on the Akaike information criterion (AIC) and permutation tests. Additionally, we examined the association between extragenetic factors and the risk of SPC in patients carrying hazardous HLA alleles.

RESULTS

During a median follow-up of 3.11 years, a total of 2894 (6.09%) participants developed SPC. We identified three protective HLA alleles (DRB1*04:03 and DPA1*02:02 for males and DRB5*01:01 for females) and two hazardous alleles (A*26:01 for males and DPB1*11:01 for females) about SPC. The presence of the protective alleles was associated with a reduced SPC risk (males: hazard ratio [HR] 0.72, 95% confidence interval [CI] 0.59-0.89; females: HR 0.81, 95% CI 0.70-0.93), while the hazardous alleles were linked to an increased risk (males: HR 1.27, 95% CI 1.03-1.56; females: HR 1.35, 95% CI 1.07-1.70). The hazardous allele A*26:01 indicated skin-lung organ-specific SPC occurrence in males. Animal fat and vitamin C were associated with SPC risk in males carrying the hazardous alleles, while free sugar and vegetable fat were linked to SPC risk in females.

CONCLUSIONS

These results suggest that HLA alleles may serve as biomarkers for the susceptibility and organ-specific occurrence of SPC, while dietary modulation may mitigate hazardous alleles-related SPC risk, potentially aiding in the early prediction and prevention of SPC.

Gender disparities in Behçet's syndrome: identifying distinct phenotypes through cluster analysis

Behçet's syndrome (BS) is a complex, multi-systemic disorder with a global occurrence, notably concentrated along the Silk Road. This study aimed to investigate gender-specific expressions and clinical phenotypes in BS patients within the Eastern Black Sea Region of Turkey. A total of 290 BS patients were retrospectively analyzed between January 2013 and December 2023. Demographic characteristics, clinical manifestations, medical treatment, and pathergy test results were obtained from a review of medical records. The mean age was 45.79 ± 13.05, with a male-to-female ratio of 48.6:51.4. Male patients had higher papulopustular lesions (p < 0.001) and ocular involvement (p = 0.036), while females showed more frequent genital ulcers (p = 0.032). Medication usage showed gender-based variations, notably higher corticosteroid, azathioprine, and tumor necrosis factor-alpha inhibitor (TNFi) use in males (p < 0.001). Cluster analysis revealed five distinct clusters, each with unique features and gender predominance. Cardiovascular type, ocular type, and skin type predominantly featured male patients, while joint involvement type and neurologic and mucosal involvement type were more prevalent among female patients with BS. This research contributes valuable insights into the gender-related clinical variations of BS within a specific geographic region, fostering a more comprehensive understanding of this challenging syndrome. The identification of distinct clinical phenotypes facilitates the development of tailored treatment strategies, potentially leading to improved outcomes for patients with BS.

Regulatory role of the lncRNAs MIAT and PVT1 in Behçet's disease through targeting miR-93-5p and miR-124-3p

BACKGROUND

Noncoding RNAs play pivotal roles in the process of autoimmune diseases. However, the definite contributions of these molecules to Behçet's disease (BD) are still unknown. This study aimed to explore the clinical value of a novel competing endogenous (ce) RNA network in the pathogenesis of BD and to assess its use in primary diagnosis.

METHODS

Bioinformatic analysis was applied to construct a BD-related ceRNA network: lncRNA (MIAT and PVT1)-miRNA (miR-93-5p and miR-124-3p)-mRNA (SOD-2 and MICA). Blood was obtained from 70 BD patients and 30 healthy subjects, and the serum expression of the tested RNAs was estimated via quantitative real-time PCR (qPCR). Serum tumor necrosis factor-alpha (TNF-α) levels were also determined. The associations between these RNAs were further analyzed, and receiver operating characteristic (ROC) curve and logistic regression analyses were employed to validate their diagnostic and prognostic values.

RESULTS

The expression levels of the lncRNAs PVT1 and miR-93-5p were significantly increased, whereas those of the lncRNAs MIAT and miR-124-3p, as well as those of the SOD-2 and MICA mRNAs, were significantly decreased in BD patients compared with controls. BD patients had significantly higher serum TNF-α levels than controls did. ROC curve analysis indicated that the selected RNAs could be candidate diagnostic biomarkers for BD. Moreover, the highest diagnostic efficiency was achieved with the combination of MIAT and miR-93-5p or PVT1 and miR-124-3p with either SOD-2 or MICA. Logistic regression analysis revealed that all RNA expression levels could be predictors for BD.

CONCLUSION

Mechanistically, our research revealed a novel ceRNA network that is significantly disrupted in BD. The findings reported herein, highlight the noncoding RNA-molecular pathways underlying BD and identify potential targets for therapeutic intervention. These insights will likely be applicable for developing new strategies for the early diagnosis, management and risk assessment of BD as well as the design of novel preventive measures. Trial registration The protocol for the clinical studies was approved by Cairo University's Faculty of Pharmacy's Research Ethics Committee (approval number: BC 3590).

Folliculitis might be associated with pathergy-positivity in patients with Behçet syndrome

Pathergy test indicates nonspecific hyper-reactivity of the skin to aseptic trauma in Behçet syndrome (BS) and is considered as an adjunctive diagnostic test with a good specificity albeit with low sensitivity. We tested the hypothesis that a relationship exists between active clinical manifestations of BS and the pathergy-positivity when performed simultaneously. Pathergy test and detailed dermatologic examination were done in 105 BS patients (60M/45F); who were seen consecutively at the multi-disciplinary BS outpatient clinic in a single tertiary center. Information regarding demographic and clinical characteristics, pathergy test results at diagnosis, and details about treatment were obtained from patient charts. Disease activity was assessed using Behçet Disease Current Activity Form. Among 105 patients, 27 (25.7%) were pathergy-positive at the time of the study visit whereas 40.9% were pathergy-positive at the time of the diagnosis. There was no relation between pathergy test and patient age or disease duration, either. Pathergy-positivity was significantly more common in patients with folliculitis compared to those without folliculitis (40.7% vs 19.2%; P = .026). The test was also positive in all 3 patients with leg ulcers due to venous stasis. We found that among all skin-mucosa lesions only the presence of folliculitis was associated with pathergy positivity with statistical significance. It was also remarkable that the current pathergy was positive in all 3 patients with active leg ulcers but this finding warrants further studies because of the low patient numbers.

Behçet's syndrome

Behçet's syndrome is a rare, chronic multisystemic inflammatory disorder also known as the Silk Route disease due to its geographical distribution. Behçet's syndrome is a multifactorial disease and infectious, genetic, epigenetic, and immunological factors contribute to its pathogenesis. Its heterogeneous spectrum of clinical features include mucocutaneous, articular, ocular, vascular, neurological, and gastrointestinal manifestations that can present with a relapsing and remitting course. Differential diagnosis is often hampered by the non-specific clinical presentation and the absence of laboratory biomarkers or pathognomonic histological features. The therapeutic approach is tailored on the basis of patient-specific manifestations and relies on glucocorticoids, colchicine, and traditional and biological immunosuppressants. Despite progress in the knowledge and management of the disease, unmet needs in diagnostics, monitoring, prediction, and treatment personalisation challenge clinical practice, making Behçet's syndrome a complex disorder associated with an increased risk of morbidity.

Trends in health care of patients with vasculitides, including giant cell arteritis, Takayasu arteritis, ANCA-associated vasculitis and Behçet's disease: cross-sectional data of the German National Database 2007-2021

The aim of this study is to present the current care situation of patients with giant cell arteritis (GCA), Takayasu arteritis (TAK), ANCA-associated vasculitis (AAV) and Behçet's disease (BD). Trends over the last 15 years will reflect improvements and remaining deficits in the management of vasculitides. Consecutive cross-sectional data from patients with vasculitides from the German National Database (NDB) of the Collaborative Arthritis Centres between 2007 and 2021 were included. Medication, physician- and patient-reported outcomes on disease activity and disease burden, inpatient stays and occupational participation are compared for different vasculitis entities and over time. Employment rates were compared to German population rates. Between 502 and 854 vasculitis patients were annually documented. GCA and AAV were the most common vasculitides. Median disease duration ranged from 2 to 16 years. Over the years, glucocorticoids decreased in proportion and dose, most markedly in GCA and TAK, while biologic therapies increased up to 27%. Physicians rated disease activity as low for the vast majority of patients, while patients-reported moderate outcomes in many dimensions. PROs remained largely unchanged. The proportion of employed patients (< 65 years) increased from 47 to 57%. In recent years, biologics are increasingly used in patients with vasculitides, while glucocorticoids decreased significantly. PRO's have not improved. Work participation increased but remains lower than that in the German population.

Relevance of vein wall thickness in Behcet's disease: A systematic review and meta-analysis

OBJECTIVES

To perform a meta-analysis on articles evaluating the common femoral vein wall thickness (VWT) in Behcet's disease and its possible clinical, laboratory and treatment correlates (BD).

METHODS

Systematic search of EMBASE and PubMed databases from inception to October 2023; we employed random effect meta-analyses for continuous outcomes.

RESULTS

The meta-analysis included 9 case-control and 1 cohort study: the VWT was greater in BD (n = 650) than in controls (n = 396) (p < 0.0001) with wide heterogeneity (I2 = 94.4%); a sensitivity analysis that included mean age of BD participants, gender, disease duration and activity, C-reactive protein, smoking status, immune-suppressive and anti-inflammatory medication, revealed that the heterogeneity variance was partly explained by age (p < 0.0001), male gender (p = 0.03), disease duration (p < 0.0001) and smoking (p = 0.06). The VWT was greater in BD with thrombotic/vascular (n = 189) than in non-thrombotic/vascular BD (n = 140) (p = 0.006) with no heterogeneity.

CONCLUSION

VWT is greater in BD than controls: age, male gender, disease duration and smoking relate to VWT that was greater in BD patients with a history of thrombotic/vascular disease. Prospective studies are required to assess whether VWT may be considered a vascular marker of disease activity.

Behçet's Disease: A Comprehensive Review on the Role of HLA-B*51, Antigen Presentation, and Inflammatory Cascade

Behçet's disease (BD) is a complex, recurring inflammatory disorder with autoinflammatory and autoimmune components. This comprehensive review aims to explore BD's pathogenesis, focusing on established genetic factors. Studies reveal that HLA-B*51 is the primary genetic risk factor, but non-HLA genes (ERAP1, IL-10, IL23R/IL-12RB2), as well as innate immunity genes (FUT2, MICA, TLRs), also contribute. Genome-wide studies emphasize the significance of ERAP1 and HLA-I epistasis. These variants influence antigen presentation, enzymatic activity, and HLA-I peptidomes, potentially leading to distinct autoimmune responses. We conducted a systematic review of the literature to identify studies exploring the association between HLA-B*51 and BD and further highlighted the roles of innate and adaptive immunity in BD. Dysregulations in Th1/Th2 and Th17/Th1 ratios, heightened clonal cytotoxic (CD8+) T cells, and reduced T regulatory cells characterize BD's complex immune responses. Various immune cell types (neutrophils, γδ T cells, natural killer cells) further contribute by releasing cytokines (IL-17, IL-8, GM-CSF) that enhance neutrophil activation and mediate interactions between innate and adaptive immunity. In summary, this review advances our understanding of BD pathogenesis while acknowledging the research limitations. Further exploration of genetic interactions, immune dysregulation, and immune cell roles is crucial. Future studies may unveil novel diagnostic and therapeutic strategies, offering improved management for this complex disease.

Clinical trait-specific genetic analysis in Behçet's disease identifies novel loci associated with ocular and neurological involvement

Behçet's disease is a complex inflammatory vasculitis with a broad spectrum of clinical manifestations. The purpose of this study was to investigate the genetics underlying specific clinical features of Behçet's disease. A total of 436 patients with Behçet's disease from Turkey were studied. Genotyping was performed using the Infinium ImmunoArray-24 BeadChip. After imputation and quality control measures, logistic regressions adjusting for sex and the first five principal components were performed for each clinical trait using a case-case genetic analysis approach. A weighted genetic risk score was calculated for each clinical feature. Genetic association analyses of previously identified susceptibility loci in Behçet's disease revealed a genetic association between ocular lesions and HLA-B/MICA (rs116799036: OR = 1.85 [95% CI = 1.35-2.52], p-value = 1.1 × 10-4). The genetic risk score was significantly higher in Behçet's disease patients with ocular lesions compared to those without ocular involvement, which is explained by the genetic variation in the HLA region. New genetic loci predisposing to specific clinical features in Behçet's disease were suggested when genome-wide variants were evaluated. The most significant associations were observed in ocular involvement with SLCO4A1 (rs6062789: OR = 0.41 [95% CI = 0.30-0.58], p-value = 1.92 × 10-7), and neurological involvement with DDX60L (rs62334264: OR = 4.12 [95% CI 2.34 to 7.24], p-value = 8.85 × 10-7). Our results emphasize the role of genetic factors in predisposing to specific clinical manifestations in Behçet's disease, and might shed additional light into disease heterogeneity, pathogenesis, and variability of Behçet's disease presentation across populations.

Treat to target in Behcet's disease: Should we follow the paradigm of other systemic rheumatic diseases?

During the last decades the efficacy of biologic agents, mainly of anti-TNFs, in controlling the activity of serious manifestations of Behcet's Disease (BD) has been established. On the other hand, the clinical heterogeneity of BD has precluded the validation of a widely-accepted composite index for disease assessment and for target disease-state definitions, such as low disease activity and remission, and the testing of their implementation in clinical practice. Therefore, in contrast to other systemic rheumatic diseases, a treat-to-target strategy has not yet been developed in BD. There are several challenges towards this approach, including standardization of outcome measures for assessing the disease activity in each-affected organ and construction of a composite disease activity index. The challenges for the development of a treat-to-target strategy and possible solutions are discussed in this position paper, which stemmed from a round table discussion that took place in the 19th International Conference on BD.

Deregulated DNA damage response network in Behcet's disease

Behcet's disease (BD) is a chronic, relapsing systemic vasculitis of unknown etiology. Since the DNA repair enzyme NEIL1 has been identified as one of the two genetic risk factors for BD by whole exome study, we examined the potential involvement of the DNA damage response (DDR) network in BD. Peripheral blood mononuclear cells from 26 patients and 26 age-/sex-matched healthy controls were studied. Endogenous DNA damage levels were increased in active BD patients compared to controls or patients in remission. In parallel, BD patients had defective nucleotide excision repair capacity. RNA-sequencing revealed reduced expression of NEIL1 that negatively correlated with DNA damage accumulation. On the other hand, expression of genes involved in senescence and senescence-associated secretory phenotype positively correlated with individual endogenous DNA damage levels. We conclude that deregulated DDR contributes to the proinflammatory environment in BD.

DIFFERENCES IN BEHÇET’S DISEASE PHENOTYPE ACCORDING TO SEX: HYPOTHESES AND RESEARCH PERSPECTIVES

Behçet's disease (BD) is a multisystem vasculitis affecting both arteries and veins. Although the disease affects both sexes equally, males and females may express different phenotypes. The exact association between sex-related factors and BD phenotype is not clear, while many factors, such as genetic factors, hormones, and environmental and epigenetic factors may be the underlying factors of sex-related differences. This article summarizes the current literature focusing on the underlying factors determining differences in BD phenotype according to sex.