The genetics of Takayasu arteritis

Genetics of vasculitis

Systemic vasculitis encompasses a wide range of conditions characterized by varying degrees of inflammation in blood vessels. Although the etiology of vasculitis remains unclear, accumulated data suggest that it is triggered in genetically predisposed individuals by the concurrence of certain environmental factors. The importance of the genetic component has been consistently supported by evidence of familial aggregation, differential prevalence by ethnicity, and multiple genetic associations with disease susceptibility and severity reported in recent years. The strongest association signals in most vasculitides correspond to genetic variants within the HLA region, suggesting an important role of the immune system in its pathophysiology. However, each type of vasculitis has distinct defining HLA association markers, likely due to disease-specific differences in antigenic drivers. Furthermore, other genetic polymorphisms located outside the HLA region play an important role in susceptibility to different vasculitides. More recent research has assessed the shared genetic susceptibility evident across different vasculitides. Future studies should focus on the identification of genetic markers that can serve as reliable biomarkers for early diagnosis, prognosis, and treatment response in systemic vasculitis.

Frequency and the effects of spondyloarthritis-spectrum disorders on the clinical course and management of Takayasu arteritis: an observational retrospective study

OBJECTIVES

Extravascular findings of Takayasu arteritis (TAK) often share features with the spondyloarthritis (SpA) spectrum of disorders. However, the characteristics of this overlap and its effect on the vascular manifestations of TAK are not fully known. Therefore, we aimed to investigate the frequency of SpA-related features in TAK patients.

MATERIAL AND METHODS

In this observational retrospective study, 350 patients with TAK classified according to ACR 1990 criteria, from 12 tertiary rheumatology clinics, were included and evaluated for the presence of axSpA, IBD, or psoriasis. Demographic, clinical features, angiographic involvement patterns, disease activity, and treatments of TAK patients with or without SpA were analyzed.

RESULTS

Mean age was 45.5 ± 13.6 years and mean follow-up period was 76.1 ± 65.9 months. Among 350 patients, 31 (8.8%) had at least one additional disease from the SpA spectrum, 8 had IBD, 8 had psoriasis, and 20 had features of axSpA. In the TAK-SpA group, TAK had significantly earlier disease onset, compared to TAK-without-SpA (p = 0.041). SpA-related symptoms generally preceded TAK symptoms. Biological treatments, mostly for active vasculitis, were higher in the TAK-SpA group (70.9%) compared to TAK-without-SpA (27.9%) (p < 0.001). Vascular involvements were similar in both.

CONCLUSION

Our study confirmed that diseases in the SpA spectrum are not rare in TAK. Vascular symptoms appeared earlier in such patients, and more aggressive therapy with biological agents was required in the TAK-SpA group, suggesting an association between TAK and SpA spectrum. Key Points • The pathogenesis of Takayasu arteritis is mediated by an MHC class I alelle (HLA-B*52), similar to spondyloarthritis-disorders. • Extravascular findings of Takayasu arteritis are in the spectrum of spondyloarthritis disease. • This frequent coexistence between Takayasu arteritis and spondyloarthritic disorders suggests a relationship rather than a coincidence.

A clinical case of Takayasu disease: emphasis on cardiac manifestations

Takayasu arteriitis (TA) is a rare systemic vasculitis, affecting large vessels, cardiac valves and myocardium. Cardiac involvement is a major cause of morbidity and mortality in such patients. This publication presents a clinical case of a patient with severe aortic regurgitation combined with restrictive cardiomyopathy. It is emphasized that surgical treatment is associated with potential difficulties in patients with TA due to its inflammatory nature, disease activity and multiorgan involvement.

Infantile Takayasu: clinical features and long-term outcome

OBJECTIVES

Takayasu arteritis (TAK) is a large-vessel vasculitis rarely reported in children and infants. Most articles on paediatric TAK have not focused on infants. We present the largest case series of infantile TAK, aiming to identify its demographic and clinical characteristics and compare them with existing data on older children.

METHODS

We conducted an international multicentre retrospective cohort study. Epidemiological and clinical data were collected from patients' charts from six rheumatology centres. All patients met both the EULAR/PReS 2008 criteria and the 1990 ACR/EULAR criteria and were diagnosed with TAK at age <5 years.

RESULTS

Twelve patients were included (50% female). Median age of symptom onset was 11 months, with a diagnostic delay of 4 months. The most common symptoms at presentation were hypertension, blood pressure differences between limbs, and fever. The most commonly involved arteries were the abdominal aorta and renal artery. Medications included steroids, conventional and biologic DMARDs, and other immunosuppressive therapies. Half of the patients received biologic agents, of which infliximab had the highest complete remission rate (40%). Other medications resulting in complete remission were CYC (40%) and MTX (38%). Invasive procedures were required for 58% of patients. The most common complications were cardiac (50%), stroke (42%), and serious infections (33%). No patients died.

CONCLUSION

This study presents the largest series of infantile TAK. Compared with other reported series on older children, infants with TAK have more severe disease and were more likely to receive biologic agents, develop complications, and require invasive interventions.

Autoimmune Heart Disease: A Comprehensive Summary for Forensic Practice

Autoimmune heart disease is a non-random condition characterised by immune system-mediated aggression against cardiac tissue. Cardiac changes often exhibit nonspecific features and, if unrecognised, can result in fatal outcomes even among seemingly healthy young individuals. In the absence of reliable medical history, the primary challenge lies in differentiating between the various cardiopathies. Numerous immunohistochemical and genetic studies have endeavoured to characterise distinct types of cardiopathies, facilitating their differentiation during autopsy examinations. However, the presence of a standardised protocol that forensic pathologists can employ to guide their investigations would be beneficial. Hence, this summary aims to present the spectrum of autoimmune cardiopathies, including emerging insights such as SARS-CoV-2-induced cardiopathies, and proposes the utilisation of practical tools, such as blood markers, to aid forensic pathologists in their routine practice.

Pathophysiology, Diagnosis, and Management of Takayasu Arteritis: A Review of Current Advances

Takayasu arteritis (TA) is a rare, chronic, inflammatory vasculitis that primarily affects large arteries, causing significant morbidity and mortality. This review provides an overview of the pathophysiology, diagnosis, and management of TA based on current advances in the field. TA is characterized by autoimmune-mediated inflammation, vascular remodeling, and endothelial dysfunction. The disease progresses through three stages (active, chronic, and healing phase) each presenting distinct clinical features. Diagnosis of TA can be challenging due to non-specific clinical manifestations and the lack of specific diagnostic tests. Various imaging modalities, such as angiography, ultrasound, and Doppler techniques, play a crucial role in the diagnosis of TA by visualizing arterial involvement and assessing disease extent. Management of TA involves a multidisciplinary approach, with disease-modifying anti-rheumatic drugs (DMARDs) as the cornerstone of medical therapy. Synthetic and biologic DMARDs are used to induce remission, control inflammation, and prevent complications. Non-pharmacologic interventions, such as resistance exercises and curcumin supplementation, show potential benefits. Invasive interventions, including endovascular therapy and open surgery, are used for managing vascular lesions. However, challenges remain in disease understanding and management, including the heterogeneity of disease presentation and the lack of standardized treatment guidelines. The future of TA management lies in precision medicine, utilizing biomarkers and molecular profiling to personalize treatment approaches and improve patient outcomes. Further research is needed to unravel the underlying mechanisms of TA and develop targeted therapies.

A comprehensive guide for managing the reproductive health of patients with vasculitis

Vasculitides and their therapies affect all areas of the reproductive life cycle. The ACR, EULAR and the Drugs and Lactation database offer guidance on the management of the reproductive health of patients with rheumatic diseases; however, these guidelines do not address patients with vasculitis specifically. This Review discusses the guidance from multiple expert panels and how these recommendations might apply to men and women with vasculitis, including the safety of contraception, use of assisted reproductive technology, preservation of fertility during cyclophosphamide therapy, disease management in pregnancy and the use of medications compatible with pregnancy and lactation. These discussions are augmented by the existing literature on vasculitis in pregnancy to enable physicians to provide comprehensive, precise and high quality care to patients with vasculitis. The contents of this Review, in conjunction with educational tools, serve to empower patients and physicians to participate in shared decision-making regarding pregnancy prevention, planning and management.

This Review discusses how best to manage the reproductive health of patients with vasculitis, including the safety of contraception, the use of assisted reproductive technology, preservation of fertility during therapy, disease management in pregnancy and the use of medications compatible with pregnancy and lactation.

Rheumatologists have the opportunity to initiate discussions with patients with vasculitis regarding family planning to make proactive decisions leading to improved pregnancy planning, management and outcomes.

Birth control options and infertility interventions for women with vasculitis depend on their risk of thrombosis, serological profile and comorbid conditions.

The majority of pregnancies in patients with vasculitis can be successful with the use of advanced family planning, medications compatible with pregnancy and lactation, and multidisciplinary collaboration among specialists.

Vasculitis exacerbations and pregnancy complications can present with similar and overlapping clinical manifestations.

Multiple expert panels provide guidelines and risk stratification regarding medication use in pregnancy and breastfeeding that can be applied to patients with vasculitis.

Giant Cell Arteritis: A Case-Based Narrative Review of the Literature

Purpose of Review

Giant cell arteritis (GCA) is a chronic, inflammatory condition, primarily affecting the medium and larger arteries. The purpose of this narrative review is to describe GCA in the context of headache and facial pain, based on a case and the available current literature. Understanding the etiology, pathophysiology, the associated conditions, and the differential diagnoses is important in managing GCA.

Recent Findings

In a patient presenting with unilateral facial/head pain with disturbances of vision, GCA should be considered in the differential diagnosis. There is an association of GCA with several comorbid conditions, and infections including coronavirus-19 (COVID-19) infection. Management of GCA primarily depends upon the identification of the affected artery and prompt treatment. Permanent visual loss and other serious complications are associated with GCA.

Summary

GCA is characterized by robust inflammation of large- and medium-sized arteries and marked elevation of systemic mediators of inflammation. An interdisciplinary approach of management involving the pertinent specialties is strongly recommended.

Whole Exome Sequencing Revealed Variants That Predict Pulmonary Artery Involvement in Patients with Takayasu Arteritis

Purpose

To conduct the first whole exome sequencing (WES) on Takayasu arteritis (TAK) to identify common and rare variants responsible for disease susceptibility.

Patients and Methods

A total of 200 patients and 1675 healthy controls from China were recruited for this study. Site-based association analysis for common variants and gene-based burden analysis for rare variants were conducted. A weighted genetic risk score (wGRS) was calculated for each patient with TAK based on the independent risk alleles identified in the association analyses. The ability of the patient wGRS to discriminate between different phenotypes was evaluated.

Results

In the site-based analysis, the top association signal was CCHCR1 (rs1265067, p = 8.27 × 10^-12, OR = 2.41), a proxy for HLA-B*52:01. HLA-DQB1 (rs9273902), HLA-DQB2 (rs34109750), and a haplotype block in the human leukocyte antigen (HLA) class III region (represented by rs3130618) also exhibited significant associations independently. In addition, four novel non-HLA susceptibility loci were identified: PRRT4, TLL2, LRP1B, and DLGAP2. Twelve independently associated single nucleotide polymorphisms were used to calculate the wGRS. TAK patients with a higher wGRS were found to have an increased risk of pulmonary artery involvement compared with those with a lower wGRS (p = 5.76 × 10^-7, OR = 13.92). The wGRS algorithm showed good predictive capability for pulmonary artery involvement in TAK (sensitivity, 92.1%; specificity, 59.9%). In the gene-based analysis, risk genes that reached exome-wide significance were not identified.

Conclusion

This WES study on TAK supports a previously reported association within the HLA region. Moreover, novel susceptibility loci were identified outside the HLA region. These risk alleles showed potential associations with pulmonary artery involvement in TAK. However, additional studies are warranted to verify our findings.

Giant cell arteritis versus Takayasu's Arteritis: Two sides of the same coin?

There are multiple vasculitides which are distinguished based on multiple criteria, including size of affected vessels, distribution of vessels affected, histopathologic differences, genetic factors, and age at presentation. Takayasu's arteritis (TkA) and giant cell arteritis (GCA) are the two main medium to large vessel vasculitides. These vasculitides are associated with different racial predilections, vascular distributions, age groups, diagnostic criteria, and treatments. Nevertheless, the many shared histopathologic features, genetic factors, and overlap in presentation of these two diseases suggest that they may actually be variable presentations of the same disease process, i.e., large vessel vasculitis. This article will review the genetics, histopathology, disease mechanisms, and diagnostic criteria for both TkA and GCA. Overall, despite major advances our understanding of these two diseases, it is still debated whether these two large vessel vasculitides represent two distinct diseases processes or simply variations of the same disease.

Childhood-onset Takayasu arteritis

PURPOSE OF REVIEW

Takayasu arteritis is a rare chronic granulomatous large vessel vasculitis that predominantly affects the aorta and its branches. The purpose of this review is to unite the current knowledge regarding the pathophysiology, cause, and epidemiology as well as diagnosis, prognosis, and treatment of this condition in children.

RECENT FINDINGS

Although the etiopathogenesis is not fully understood, studies suggest an autoimmune basis for the disease as well as a genetic predisposition. It is a disease primarily affecting young women with up to a third of cases with onset in childhood. There are distinct features of childhood-onset Takayasu arteritis (cTA) that merit this separate review. Diagnostic criteria and clinical manifestations are unique in pediatric patients with renovascular hypertension being the most prevalent presentation. Traditional treatments involving high-dose corticosteroids and cytotoxic agents are being reconsidered for less toxic contemporary biologic agents. Current algorithms for treatment include early introduction of corticosteroid-sparing agents, such as methotrexate or mycophenolate as well as tumor necrosis factor-alpha (TNF-α) inhibitor (infliximab, adalimumab) and/or interleukin-6 (IL-6) receptor inhibitor (tocilizumab).

SUMMARY

Early diagnosis of cTA with goals to develop effective and well tolerated treatment paradigms are essential to improve the long-term prognosis of this rare and devastating disease.

Large-vessel vasculitis

Large-vessel vasculitis (LVV) manifests as inflammation of the aorta and its major branches and is the most common primary vasculitis in adults. LVV comprises two distinct conditions, giant cell arteritis and Takayasu arteritis, although the phenotypic spectrum of primary LVV is complex. Non-specific symptoms often predominate and so patients with LVV present to a range of health-care providers and settings. Rapid diagnosis, specialist referral and early treatment are key to good patient outcomes. Unfortunately, disease relapse remains common and chronic vascular complications are a source of considerable morbidity. Although accurate monitoring of disease activity is challenging, progress in vascular imaging techniques and the measurement of laboratory biomarkers may facilitate better matching of treatment intensity with disease activity. Further, advances in our understanding of disease pathophysiology have paved the way for novel biologic treatments that target important mediators of disease in both giant cell arteritis and Takayasu arteritis. This work has highlighted the substantial heterogeneity present within LVV and the importance of an individualized therapeutic approach. Future work will focus on understanding the mechanisms of persisting vascular inflammation, which will inform the development of increasingly sophisticated imaging technologies. Together, these will enable better disease prognostication, limit treatment-associated adverse effects, and facilitate targeted development and use of novel therapies.

MRI diagnosis of Takayasu arteritis in a young woman

Takayasu arteritis is a rare type of chronic, granulomatous vasculitis, characterized by inflammation of blood vessels of large caliber, such as the aorta, and its branches. Clinical presentation varies, depending on the severity of symptoms. Onset may be gradual, however at times, presentation may be acute, and life threatening. Herein, we present the case of a 29-year-old female, 3 months post-op, following a right carotid artery stenting procedure. The patient presented with nonspecific symptoms of malaise, arthralgia, and blurry vision. Clinical presentation and imaging findings were consistent with Takayasu's Arteritis.

Application progress of multiple imaging modalities in Takayasu arteritis

Takayasu arteritis (TA) is a chronic, idiopathic, granulomatous large vessel vasculitis of unknown etiology. The clinical manifestations of TA are incredibly variable, mainly depending on the location of the lesions. In the light of its insidious progress and the diversity of clinical manifestations, a substantial proportion of patients might experience a considerable delay in diagnosis, which leads to irreversible malignant complications, highlighting the importance of early diagnosis. There has been accumulating evidence that early identification of disease is pivotal to initiate timely therapy and ameliorate the prognosis. Therefore, this review discusses and summarizes the latest evidence on the application progress of multiple imaging modalities.

KLRD1, FOSL2 and LILRB3 as potential biomarkers for plaques progression in acute myocardial infarction and stable coronary artery disease

BACKGROUND

Myocardial infarction (MI) contributes to high mortality and morbidity and can also accelerate atherosclerosis, thus inducing recurrent event due to status changing of coronary artery walls or plaques. The research aimed to investigate the differentially expressed genes (DEGs), which may be potential therapeutic targets for plaques progression in stable coronary artery disease (CAD) and ST-elevated MI (STEMI).

METHODS

Two human datasets (GSE56885 and GSE59867) were analyzed by GEO2R and enrichment analysis was applied through Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis. To explore the seed genes, the protein-protein interaction (PPI) network was constructed and seed genes, as well as top30 ranking neighbours were screened out. To validate these findings, one human dataset GSE120521 was analyzed. Linear regression analysis and ROC curve were also performed to determine which seed genes above mentioned could be independent factors for plaques progression. Mice MI model and ELISA of seed genes were applied and ROC curve was also performed for in vivo validation.

RESULTS

169 DEGs and 573 DEGs were screened out in GSE56885 and GSE59867, respectively. Utilizing GO and KEGG analysis, these DEGs mainly enriched in immune system response and cytokines interaction. PPI network analysis was carried out and 19 seed genes were screened out. To validate these findings, GSE120521 was analyzed and three genes were demonstrated to be targets for plaques progression and stable CAD progression, including KLRD1, FOSL2 and LILRB3. KLRD1 and LILRB3 were demonstrated to be high-expressed at 1d after MI compared to SHAM group and FOSL2 expression was low-expressed at 1d and 1w. To investigate the diagnostic abilities of seed genes, ROC analysis was applied and the AUCs of KLRD1, FOSL2 and LILRB3, were 0.771, 0.938 and 0.972, respectively.

CONCLUSION

This study provided the screened seed genes, KLRD1, FOSL2 and LILRB3, as credible molecular biomarkers for plaques status changing in CAD progression and MI recurrence. Other seed genes, such as FOS, SOCS3 and MCL1, may also be potential targets for treatment due to their special clinical value in cardiovascular diseases.

Atypical presentation of Takayasu aortitis and myocarditis contributing to sudden death in a young Canadian first nations adult

This is a rare presentation of Takayasu arteritis in a 30-year-old Canadian First Nations woman with cardiac and aortic root-predominant disease, which manifested in complete heart block. She had a past medical history significant for substance misuse. At presentation, cardiac magnetic resonance imaging identified diffuse thickening of the left atrium and ventricular outflow tract with left ventricular cavity dilation and preserved systolic function. A pacemaker was inserted at this time. Nine months later, the patient died following an out-of-hospital cardiac arrest in the context of cocaine intoxication. At autopsy, the cardiac thickening was also found to involve the proximal aortic root, which on microscopy demonstrated non-infectious aortitis and myocarditis with a granulomatous inflammatory pattern and dense fibrosis indicative of Takayasu arteritis. Important clinical clues to the diagnosis include age, sex, and Pacific Islands, American indigenous and Asian ethnicity. The case also underscores the need to rule out secondary causes of complete heart block, including systemic vasculitides, for all patients regardless of substance use history.

Leukocyte immunoglobulin-like receptor subfamily B: therapeutic targets in cancer

Inhibitory leukocyte immunoglobulin-like receptors (LILRBs 1–5) transduce signals via intracellular immunoreceptor tyrosine-based inhibitory motifs that recruit phosphatases to negatively regulate immune activation. The activation of LILRB signaling in immune cells may contribute to immune evasion. In addition, the expression and signaling of LILRBs in cancer cells especially in certain hematologic malignant cells directly support cancer development. Certain LILRBs thus have dual roles in cancer biology—as immune checkpoint molecules and tumor-supporting factors. Here, we review the expression, ligands, signaling, and functions of LILRBs, as well as therapeutic development targeting them. LILRBs may represent attractive targets for cancer treatment, and antagonizing LILRB signaling may prove to be effective anti-cancer strategies.

Identification of susceptibility loci for Takayasu arteritis through a large multi-ancestral genome-wide association study

Takayasu arteritis is a rare inflammatory disease of large arteries. We performed a genetic study in Takayasu arteritis comprising 6,670 individuals (1,226 affected individuals) from five different populations. We discovered HLA risk factors and four non-HLA susceptibility loci in VPS8, SVEP1, CFL2, and chr13q21 and reinforced IL12B, PTK2B, and chr21q22 as robust susceptibility loci shared across ancestries. Functional analysis proposed plausible underlying disease mechanisms and pinpointed ETS2 as a potential causal gene for chr21q22 association. We also identified >60 candidate loci with suggestive association (p < 5 × 10^-5) and devised a genetic risk score for Takayasu arteritis. Takayasu arteritis was compared to hundreds of other traits, revealing the closest genetic relatedness to inflammatory bowel disease. Epigenetic patterns within risk loci suggest roles for monocytes and B cells in Takayasu arteritis. This work enhances understanding of the genetic basis and pathophysiology of Takayasu arteritis and provides clues for potential new therapeutic targets.

Pathogenesis of liver injury in Takayasu arteritis: advanced understanding leads to new horizons

Liver injury in Takayasu arteritis (TA) is a rare phenomenon. Most symptoms are nonspecific, and the exact pathogenesis remains to be elucidated. Early diagnosis and new treatment methods are important for an improved prognosis. A summary of the clinical information and mechanistic analyses may contribute to making an early diagnosis and development of new treatment methods. A PubMed search was conducted using the specific key words “Takayasu arteritis” and “liver” or “hepatitis” or “hepatic”. Symptoms and treatment of TA with an accompanying liver injury were reviewed retrospectively. Many factors are presumed to be involved in the mechanism of TA with liver injury, including the immune response, genes, infections, and gut microbiota. There are several lines of evidence indicating that immune dysfunction is the main pathogenic factor that triggers granuloma formation in TA patients. However, the role of genetics and infections has not been fully confirmed. Recently, the gut microbiota has emerged as an essential component in the process. We reviewed in detail the current concepts that support the complex pathogenesis of TA accompanied by liver injury, and we presented recent theories from the literature. Finally, we discussed future research directions of liver injury in TA.

Pathophysiology and therapy of systemic vasculitides

Systemic vasculitides represent uncommon conditions characterized by the inflammation of blood vessels that can lead to different complex disorders limited to one organ or potentially involving multiple organs and systems. Systemic vasculitides are classified according to the diameter of the vessel that they mainly affect (small, medium, large, or variable). The pathogenetic mechanisms of systemic vasculitides are still partly unknown, as well as their genetic basis. For most of the primary systemic vasculitides, a single gold standard test is not available, and diagnosis is often made after having ruled out other mimicking conditions. Current research has focused on new management protocol and therapeutic strategies aimed at improving long-term patient outcomes and avoiding progression to multiorgan failure with irreversible damage. In this narrative review, authors describe different forms of systemic vasculitides through a review of the literature, with the aim of highlighting the current knowledge and recent findings on etiopathogenesis, diagnosis and therapy.

An integrated Asian human SNV and indel benchmark established using multiple sequencing methods

Sequencing technologies have been rapidly developed recently, leading to the breakthrough of sequencing-based clinical diagnosis, but accurate and complete genome variation benchmark would be required for further assessment of precision medicine applications. Despite the human cell line of NA12878 has been successfully developed to be a variation benchmark, population-specific variation benchmark is still lacking. Here, we established an Asian human variation benchmark by constructing and sequencing a stabilized cell line of a Chinese Han volunteer. By using seven different sequencing strategies, we obtained ~3.88 Tb clean data from different laboratories, hoping to reach the point of high sequencing depth and accurate variation detection. Through the combination of variations identified from different sequencing strategies and different analysis pipelines, we identified 3.35 million SNVs and 348.65 thousand indels, which were well supported by our sequencing data and passed our strict quality control, thus should be high confidence variation benchmark. Besides, we also detected 5,913 high-quality SNVs which had 969 sites were novel and  located in the high homologous regions supported by long-range information in both the co-barcoding single tube Long Fragment Read (stLFR) data and PacBio HiFi CCS data. Furthermore, by using the long reads data (stLFR and HiFi CCS), we were able to phase more than 99% heterozygous SNVs, which helps to improve the benchmark to be haplotype level. Our study provided comprehensive sequencing data as well as the integrated variation benchmark of an Asian derived cell line, which would be valuable for future sequencing-based clinical development.

Migratory Aortitis Associated with Granulocyte-colony-stimulating Factor

We herein report a case of migratory aortitis after the administration of granulocyte-colony-stimulating factor (G-CSF) to a 65-year-old woman with a history of pancreatic cancer. She was being administered pegfilgrastim and developed aortitis around the aortic arch. Although it resolved within two weeks, she again developed aortitis around the descending aorta, presenting as migratory aortitis, after pegfilgrastim was resumed. We further experienced three additional cases of G-CSF-induced aortitis that also showed spontaneous resolution, suggesting no or short-term use of immunosuppression. Aortitis due to G-CSF can present as migratory aortitis, since aortitis can quickly resolve and inflammation can recur at a different location.

Takayasu arteritis risk locus in IL6 represses the anti-inflammatory gene GPNMB through chromatin looping and recruiting MEF2-HDAC complex

OBJECTIVE

Previous work has revealed a genetic association between Takayasu arteritis and a non-coding genetic variant in an enhancer region within IL6 (rs2069837 A/G). The risk allele in this variant (allele A) has a protective effect against chronic viral infection and cancer. The goal of this study was to characterise the functional consequences of this disease-associated risk locus.

METHODS

A combination of experimental and bioinformatics tools were used to mechanistically understand the effects of the disease-associated genetic locus in IL6. These included electrophoretic mobility shift assay, DNA affinity precipitation assays followed by mass spectrometry and western blotting, luciferase reporter assays and chromosome conformation capture (3C) to identify chromatin looping in the IL6 locus. Both cell lines and peripheral blood primary monocyte-derived macrophages were used.

RESULTS

We identified the monocyte/macrophage anti-inflammatory gene GPNMB,~520 kb from IL6, as a target gene regulated by rs2069837. We revealed preferential recruitment of myocyte enhancer factor 2-histone deacetylase (MEF2-HDAC) repressive complex to the Takayasu arteritis risk allele. Further, we demonstrated suppression of GPNMB expression in monocyte-derived macrophages from healthy individuals with AA compared with AG genotype, which was reversed by histone deacetylase inhibition. Our data show that the risk allele in rs2069837 represses the expression of GPNMB by recruiting MEF2-HDAC complex, enabled through a long-range intrachromatin looping. Suppression of this anti-inflammatory gene might mediate increased susceptibility in Takayasu arteritis and enhance protective immune responses in chronic infection and cancer.

CONCLUSIONS

Takayasu arteritis risk locus in IL6 might increase disease susceptibility by suppression of the anti-inflammatory gene GPNMB through chromatin looping and recruitment of MEF2-HDAC epigenetic repressive complex. Our data highlight long-range chromatin interactions in functional genomic and epigenomic studies in autoimmunity.

Biomarkers in Vasculitides of the Nervous System

Besides being affected by the rare and severe primary angiitis of the central nervous system (PACNS) the nervous system is also affected by primary systemic vasculitides (PSV). In contrast to PACNS, PSV affect not only the central but also the peripheral nervous system, resulting in a large array of potential symptoms. Given the high burden of disease, difficulties in distinguishing between differential diagnoses, and incomplete pathophysiological insights, there is an urgent need for additional precise diagnostic tools to enable an earlier diagnosis and initiation of effective treatments. Methods available to date, such as inflammatory markers, antibodies, cerebrospinal fluid (CSF) analysis, imaging, and biopsy, turn out to be insufficient to meet all current challenges. We highlight the use of biomarkers as an approach to extend current knowledge and, ultimately, improve patient management. Biomarkers are considered to be useful for disease diagnosis and monitoring, for predicting response to treatment, and for prognosis in clinical practice, as well as for establishing outcome parameters in clinical trials. In this article, we review the recent literature on biomarkers which have been applied in the context of different types of nervous system vasculitides including PACNS, giant-cell arteritis, Takayasu's arteritis, polyarteritis nodosa, ANCA (anti-neutrophil cytoplasm antibody)-associated vasculitides, cryoglobulinemic vasculitis, IgA vasculitis, and Behçet's disease. Overall, the majority of biomarkers is not specific for vasculitides of the nervous system.

Vasculitis: Decade in Review

BACKGROUND

In the last decade, we have come to better understand and manage the vasculitides. The classification of vasculitides has been revised. Genome- wide association studies and linkage analyses have been undertaken in hope of better understanding the pathogenesis of vasculitides. Comprehensive genetic studies have highlighted new pathways that may guide us in more targeted therapies. Description of the monogenic forms of vasculitis, such as deficiency of adenosine deaminase type 2 (DADA2), Haploinsufficiency of A20 (HA20), have introduced a new perspective to vasculopathies, and introduced alternative treatments for these diseases.

CONCLUSION

In this review, the important discoveries in pathogenesis and consensus treatment recommendations from the past decade will be summarized.

Genetic Basis of Vasculitides with Neurologic Involvement

"Vasculitides are a heterogeneous group of inflammatory diseases of blood vessels in which genetic variation plays an important role in their susceptibility and clinical spectrum. Because of the use of novel technologies and the increase of the sample size of the study cohorts, the knowledge of the genetic background of vasculitides has considerably expanded during the last years. However, few insights have been obtained regarding the genetics underlying severe clinical phenotypes, such as those related to the nervous system. In this review the authors provide an updated overview of the genetic landscape behind vasculitis predisposition and development of neurologic manifestations."

An association study in PTPN22 suggests that is a risk factor to Takayasu's arteritis

OBJECTIVES

Takayasu's arteritis (TA) represents a rare autoimmune disease (AD) characterized by systemic vasculitis that primarily affects large arteries, especially the aorta and the aortic arch and its main branches. Genetic components in TA are largely unknown. PTPN22 is a susceptibility loci for different ADs; however, the role of different PTPN22 single-nucleotide polymorphisms (SNPs) in the susceptibility to TA is not clear.

METHODS

We evaluated the PTPN22 R620W (C1858T), R263Q (G788A), and - 123G/C SNPs in a group of patients with TA and in healthy individuals from Mexico. Our study included 111 patients with TA and 314 healthy individuals. Genotyping was performed with the 5' exonuclease (TaqMan^®) assay.

RESULTS

Our data showed that the PTPN22 R620W polymorphism is a risk factor for TA (CC vs. CT: OR 4.3, p = 0.002, and C vs. T: OR 4.1, p = 0.003); however, the PTPN22 R263Q and - 1123G/C polymorphisms are not associated with this AD. In addition, the PTPN22 CGT haplotype, which carries the minor allele of the PTPN22 C1858T variant, was also associated with TA susceptibility.

CONCLUSION

This is the first report documenting an association between PTPN22 R620W and TA.

Tumor necrosis factor-alpha -308G/A gene polymorphism and novel biomarker profiles in patients with Takayasu arteritis

Background

Takayasu arteritis (TA) is an idiopathic chronic inflammatory disease of the aorta and its branches, leading to stenosis, occlusion, and aneurysmal dilatation. Tumor necrosis factor-alpha (TNF-α) is a cytokine with pleomorphic actions and plays a pivotal role in inflammation; the serum level of TNF-α is genetically determined. However, the literature lacks adequate information on the association of TNF-α polymorphisms with TA. Hence, the present study investigates the contribution of TNF-α polymorphism toward the complex etiology of TA.

Methods

A cross-sectional study was performed in 87 patients with TA and 90 controls. A promoter region polymorphism of TNF-α, rs1800629 G/A, or −308G/A was genotyped in all the study subjects followed by a case–control association study. Furthermore, to understand the biomarker profile, levels of specific markers such as erythrocyte sedimentation rate, serum high-sensitivity C-reactive protein, interleukin-18, interleukin-6, and TNF-α were measured in all the study subjects.

Results

All the inflammatory markers were significantly higher in the TA patients than in the controls. The genetic study (available for 57 TA patients and 36 controls) revealed that the TNF-α −308A allele was overrepresented in the TA patients (12% vs 7%). The TNF-α −308A allele correlated with the increased TNF-α levels, but it could not attain significance because of a small sample size.

Conclusion

The TNF-α −308G/A polymorphism is associated with TNF-α levels in Indian population, which might have implications for clinical risk stratification and treatment. The different TNF-α gene promoter polymorphism might contribute to the molecular pathogenesis of TA. However, further study of the underlying mechanism is warranted.

New Insights on the Pathogenesis of Takayasu Arteritis: Revisiting the Microbial Theory

Takayasu arteritis (TAK) is a chronic vasculitis that mainly affects the aorta, its major branches, and the pulmonary arteries. Since the description of the first case by Mikito Takayasu in 1908, several aspects of this rare disease, including the epidemiology, diagnosis, and the appropriate clinical assessment, have been substantially defined. Nevertheless, while it is well-known that TAK is associated with a profound inflammatory process, possibly rooted to an autoimmune disorder, its precise etiology has remained largely unknown. Efforts to identify the antigen(s) that trigger autoimmunity in this disease have been unsuccessful, however, it is likely that viruses or bacteria, by a molecular mimicry mechanism, initiate or propagate the auto-immune process in this disease. In this article, we summarize recent advances in the understanding of TAK, with emphasis on new insights related to the pathogenesis of this entity that may contribute to the design of novel therapeutic approaches.

The "Eternal Recurrence" of Arteritis. Suggesting Autoimmunity Underlining Friedrich Nietzsche's Challenging Clinical Case

Friedrich Wilhelm Nietzsche (Röcken 1844 -Weimar 1900), the philosopher who theorized the concept of "eternal recurrence", suffered a lifelong multifaceted chronic illness that started in pediatric age with severe headaches and ended up with stroke at the age of 56. Even though many hypothetical diagnosis have been proposed in recent years, they all failed to explain the totality of clinical conditions that co-occurred in the philosopher's extremely challenging case, and debate on the matter is still open. In this report, we suggest an autoimmune condition, specifically Takayasu's arteritis, as a possible etiology of the philosopher's illness, which could not only potentially fit all available clinical data but also be the medical counterpart of Nietzsche's philosophical thought: could eternal recurrence of arteritis explain Zarathustra's destiny? If so, could a vascular surgeon, at this time in future, be so superhuman to change it?

Novel HLA class I associations with HIV-1 control in a unique genetically admixed population

Associations between HLA class I alleles and HIV progression in populations exhibiting Amerindian and Caucasian genetic admixture remain understudied. Using univariable and multivariable analyses we evaluated HLA associations with five HIV clinical parameters in 3,213 HIV clade B-infected, ART-naïve individuals from Mexico and Central America (MEX/CAM cohort). A Canadian cohort (HOMER, n = 1622) was used for comparison. As expected, HLA allele frequencies in MEX/CAM and HOMER differed markedly. In MEX/CAM, 13 HLA-A, 24 HLA-B, and 14 HLA-C alleles were significantly associated with at least one clinical parameter. These included previously described protective (e.g. B*27:05, B*57:01/02/03 and B*58:01) and risk (e.g. B*35:02) alleles, as well as novel ones (e.g. A*03:01, B*15:39 and B*39:02 identified as protective, and A*68:03/05, B*15:30, B*35:12/14, B*39:01/06, B*39:05~C*07:02, and B*40:01~C*03:04 identified as risk). Interestingly, both protective (e.g. B*39:02) and risk (e.g. B*39:01/05/06) subtypes were identified within the common and genetically diverse HLA-B*39 allele group, characteristic to Amerindian populations. While HLA-HIV associations identified in MEX and CAM separately were similar overall (Spearman's rho = 0.33, p = 0.03), region-specific associations were also noted. The identification of both canonical and novel HLA/HIV associations provides a first step towards improved understanding of HIV immune control among unique and understudied Mestizo populations.