Risk loci involved in giant cell arteritis susceptibility: a genome-wide association study.

BACKGROUND: Giant cell arteritis is an age-related vasculitis that mainly affects the aorta and its branches in individuals aged 50 years and older. Current options for diagnosis and treatment are scarce, highlighting the need to better understand its underlying pathogenesis. Genome-wide association studies (GWAS) have emerged as a powerful tool for unravelling the pathogenic mechanisms involved in complex diseases. We aimed to characterise the genetic basis of giant cell arteritis by performing the largest GWAS of this vasculitis to date and to assess the functional consequences and clinical implications of identified risk loci. METHODS: We collected and meta-analysed genomic data from patients with giant cell arteritis and healthy controls of European ancestry from ten cohorts across Europe and North America. Eligible patients required confirmation of giant cell arteritis diagnosis by positive temporal artery biopsy, positive temporal artery doppler ultrasonography, or imaging techniques confirming large-vessel vasculitis. We assessed the functional consequences of loci associated with giant cell arteritis using cell enrichment analysis, fine-mapping, and causal gene prioritisation. We also performed a drug repurposing analysis and developed a polygenic risk score to explore the clinical implications of our findings. FINDINGS: We included a total of 3498 patients with giant cell arteritis and 15 550 controls. We identified three novel loci associated with risk of giant cell arteritis. Two loci, MFGE8 (rs8029053; p=4·96 × 10-8; OR 1·19 [95% CI 1·12-1·26]) and VTN (rs704; p=2·75 × 10-9; OR 0·84 [0·79-0·89]), were related to angiogenesis pathways and the third locus, CCDC25 (rs11782624; p=1·28 × 10-8; OR 1·18 [1·12-1·25]), was related to neutrophil extracellular traps (NETs). We also found an association between this vasculitis and HLA region and PLG. Variants associated with giant cell arteritis seemed to fulfil a specific regulatory role in crucial immune cell types. Furthermore, we identified several drugs that could represent promising candidates for treatment of this disease. The polygenic risk score model was able to identify individuals at increased risk of developing giant cell arteritis (90th percentile OR 2·87 [95% CI 2·15-3·82]; p=1·73 × 10-13). INTERPRETATION: We have found several additional loci associated with giant cell arteritis, highlighting the crucial role of angiogenesis in disease susceptibility. Our study represents a step forward in the translation of genomic findings to clinical practice in giant cell arteritis, proposing new treatments and a method to measure genetic predisposition to this vasculitis. FUNDING: Institute of Health Carlos III, Spanish Ministry of Science and Innovation, UK Medical Research Council, and National Institute for Health and Care Research.

Decoding CD4+ T cell transcriptome in giant cell arteritis: Novel pathways and altered cross-talk with monocytes.

BACKGROUND: Giant cell arteritis (GCA) is an immune-mediated large-vessels vasculitis with complex etiology. Although the pathogenic mechanisms remain poorly understood, a central role for CD4+ T cells has been demonstrated. In this context, understanding the transcriptome dysregulation in GCA CD4+ T cells will yield new insights into its pathogenesis. METHODS: Transcriptome analysis was conducted on CD4+ T cells from 70 patients with GCA with different disease activity and treatment status (active patients before treatment and patients in remission with and without glucocorticoid treatment), and 28 healthy controls. The study also evaluated potential impacts of DNA methylation on gene expression alterations and assessed cross-talk with CD14+ monocytes. RESULTS: This study has uncovered a substantial number of genes and pathways potentially contributing to the pathogenicity of CD4+ T cells in GCA. Specifically, CD4+ T cells from GCA patients with active disease exhibited altered expression levels of genes involved in multiple immune-related processes, including various interleukins (IL) signaling pathways. Notably, IL-2, a decisive interleukin for regulatory T cells homeostasis, was among the most significant. Additionally, impaired apoptotic pathways appear crucial in GCA development. Our findings also suggest that histone-related epigenetic pathways may be implicated in promoting an inflammatory phenotype in GCA active patients. Finally, our study observed altered signaling communication, such as the Jagged-Notch signaling, between CD4+ T cells and monocytes that could have pathogenic relevance in GCA. CONCLUSIONS: Our study suggests the participation of novel cytokines and pathways and the occurrence of a disruption of monocyte-T cell crosstalk driving GCA pathogenesis.

Current evidence on the role of fibroblasts in large-vessel vasculitides: From pathogenesis to therapeutics.

Large-vessel vasculitides (LVV) comprise a group of chronic inflammatory diseases of the aorta and its major branches. The most common forms of LVV are giant cell arteritis (GCA) and Takayasu arteritis (TAK). Both GCA and TAK are characterized by granulomatous inflammation of the vessel wall accompanied by a maladaptive immune and vascular response that promotes vascular damage and remodeling. The inflammatory process in LVV starts in the adventitia where fibroblasts constitute the dominant cell population. Fibroblasts are traditionally recognized for synthesizing and renewing the extracellular matrix thereby being major players in maintenance of normal tissue architecture and in tissue repair. More recently, fibroblasts have emerged as a highly plastic cell population exerting various functions, including the regulation of local immune processes and organization of immune cells at the site of inflammation through production of cytokines, chemokines and growth factors as well as cell-cell interaction. In this review, we summarize and discuss the current knowledge on fibroblasts in LVV. Furthermore, we identify key questions that need to be addressed to fully understand the role of fibroblasts in the pathogenesis of LVV.

Biological treatments in childhood asthma.

PURPOSE OF REVIEW: The aim is to update the information currently available for the use of biologics in severe asthma in children, in order to facilitate their prescription as far as possible. RECENT FINDINGS: The appearance of biologics for the treatment of severe asthma has meant a revolutionary change in the therapeutic approach to this disease. Currently, five biologics have been approved for severe asthma in children and/or adolescents by the regulatory agencies: omalizumab, mepolizumab, benralizumab, dupilumab and tezepelumab. But despite their positive results in terms of efficacy, there are still relevant points of debate that should induce caution when selecting the most appropriate biologic in a child with severe asthma. Indeed, safety is essential and, for several of the existing treatments, the availability of medium-term to long-term data in this regard is scarce. SUMMARY: The use of biologics can facilitate the therapeutic paradigm shift from pleiotropic treatments to personalized medicine. However, the choice of the most appropriate biologics remains a pending issue. On the other hand, to the extent that several of the biologics have been available for a relatively short time, the most robust evidence in terms of efficacy and safety in children is that of omalizumab.

Cranial involvement in giant cell arteritis.

Since its first clinical description in 1890, extensive research has advanced our understanding of giant cell arteritis, leading to improvements in both diagnosis and management for affected patients. Imaging studies have shown that the disease frequently extends beyond the typical cranial arteries, also affecting large vessels such as the aorta and its proximal branches. Meanwhile, advances in comprehending the underlying pathophysiology of giant cell arteritis have given rise to numerous potential therapeutic agents, which aim to minimise the need for glucocorticoid treatment and prevent flares. Classification criteria for giant cell arteritis, as well as recommendations for management, imaging, and treat-to-target have been developed or updated in the last 5 years, and current research encompasses a broad spectrum covering basic, translational, and clinical research. In this Series paper, we aim to discuss the current understanding of giant cell arteritis with cranial manifestations, describe the clinical approach to this condition, and explore future directions in research and patient care.

Possibilidades de atuação da Terapia Ocupacional no campo da saúde mental infantojuvenil: bullying e sofrimento psíquico na adolescência / Possibilities of occupational therapy in the field of chlidhood of mental health: bullying and psychic suffering in adolescence / Posibilidades de la terapia occupacional en el ambito de la salud mental infantil y juvenil: buliiyging y sofrimiento psiquico en la adolescencia

O presente trabalho objetiva abordar, por meio de um relato de experiência, as possibilidades de atuação da Terapia Ocupacional no campo da saúde mental infantojuvenil como, por exemplo, diante de situações de bullying e sofrimento psíquico vivenciados por adolescentes. Trata-se do relato de uma experiência vinculada a um projeto de ensino e extensão universitária, realizado em uma escola pública do interior do Estado de SP. As intervenções foram realizadas em três etapas: 1) Roda de conversa e compartilhamento com a equipe escolar; 2) Intervenção em sala de aula e 3) Acolhimento e acompanhamento das demandas emergidas nas etapas 1 e 2. Os resultados apontam que a ação desenvolvida auxiliou os adolescentes a reconhecerem suas potências, assim como a identificarem e lidarem com os fenômenos que lhes geram sofrimento. As estratégias adotadas caminham na direção do que tem sido sugerido e apontado pela literatura como possibilidade de atuação frente à temática do bullying, sendo a Terapia Ocupacional uma das profissões atuantes nesse campo

The present work aims to address, through an experience report, the possibilities of Occupational Therapy in the field of child and adolescent mental health, for example, in situations of bullying and psychological suffering experienced by adolescents. This is the report of an experience linked to a teaching and university extension project, carried out in a public school in the interior of the State of SP. The interventions were carried out in three stages: 1) Conversation and sharing with the school team;2) Intervention in the classroom and 3) Reception and monitoring of the demands that emerged in stages 1 and 2. The results indicate that the developmental action helped adolescents to recognize their strengths, as well as to identify and deal with the phenomena that cause them suffering. The strategies adopted move in the direction of what has been suggested and pointed out in the literature as a possibility of action in the face of bullying, with Occupational Therapy being one of the professions active in this field (AU).

El presente trabajo pretende abordar, a través de un relato de experiencia, las posibilidades de la Terapia Ocupacional en el ámbito de la salud mental infanto-juvenil, por ejemplo, en situaciones de acoso escolar y sufrimiento psicológico que viven los adolescentes. Este es el relato de una experiencia vinculada a un proyecto de enseñanza y extensión universitaria, realizado en una escuela pública del interior del Estado de SP. Las intervenciones se realizaron en tres etapas: 1) Conversación y compartir con el equipo escolar; 2) Intervención en el aula y 3) Recepción y seguimiento de las demandas surgidas en las etapas 1 y 2. Los resultados indican que la acción evolutiva ayudó a los adolescentes a reconocer sus fortalezas, así como a identificar y afrontar los fenómenos que las provocan. sufrimiento. Las estrategias adoptadas van en la dirección de lo sugerido y señalado en la literatura como una posibilidad de actuación frente al acoso escolar, siendo la Terapia Ocupacional una de las profesiones activas en este campo (AU).

Nursing students' attitude toward euthanasia following its legalization in Spain.

BACKGROUND: Euthanasia is a controversial practice in many countries. Since Spain's Euthanasia Law came into effect on March 24, 2021, healthcare providers have faced a new challenge since they must inform patients, provide care, accompany them, and implement the law. It also represents a new stumbling block at universities, which must adapt to regulatory changes and educate future professionals accordingly. Little is known about the attitude of nursing students in Spain toward euthanasia since this law was implemented. OBJECTIVE: This study aims to answer the following research questions: What is the attitude of nursing students toward euthanasia? What factors influence this attitude? RESEARCH DESIGN: A cross-sectional study was conducted using an online questionnaire. PARTICIPANTS AND RESEARCH CONTEXT: The study population comprised all nursing students at a public university in Barcelona (n = 444), Spain, during the 2022-2023 academic year. The validated Spanish version of the Euthanasia Attitude Scale was employed. A bivariate analysis was performed. ETHICAL CONSIDERATIONS: The university Ethics Committee (CEEAH 6247) approved this study. All participating students signed an informed consent form. Participation was voluntary, and data anonymity and confidentiality were guaranteed. RESULTS: Two hundred and forty-four nursing students responded to the questionnaire. The mean total score was 79.64. Participants with religious beliefs presented lower scores, indicating a more negative attitude toward euthanasia. Participants in their second, third, or fourth year of the nursing degree scored higher, demonstrating a more positive attitude. CONCLUSIONS: The attitude of nursing students toward euthanasia was remarkably positive. Working on ethical content during the degree course and clinical practice are factors that help to develop a more positive attitude. In addition, nursing education should encourage professional aspects to prevail over religious beliefs in euthanasia situations.

Significance of clinical-immunological patterns and diagnostic yield of biopsies in microscopic polyangiitis and granulomatosis with polyangiitis.

BACKGROUND: Microscopic polyangiitis (MPA) and granulomatosis with polyangiitis (GPA) are the two major antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV). OBJECTIVES: To characterize a homogenous AAV cohort and to assess the impact of clinicopathological profiles and ANCA serotypes on clinical presentation and prognosis. Clinical differences in GPA patients according to ANCA serotype and the diagnostic yield for vasculitis of biopsies in different territories were also investigated. RESULTS: This retrospective study (2000-2021) included 152 patients with AAV (77 MPA/75 GPA). MPA patients (96.1% myeloperoxidase [MPO]-ANCA and 2.6% proteinase 3 [PR3]-ANCA) presented more often with weight loss, myalgia, renal involvement, interstitial lung disease (ILD), cutaneous purpura, and peripheral nerve involvement. Patients with GPA (44% PR3-ANCA, 33.3% MPO, and 22.7% negative/atypical ANCA) presented more commonly with ear, nose, and throat and eye/orbital manifestations, more relapses, and higher survival than patients with MPA. GPA was the only independent risk factor for relapse. Poor survival predictors were older age at diagnosis and peripheral nerve involvement. ANCA serotypes differentiated clinical features in a lesser degree than clinical phenotypes. A mean of 1.5 biopsies were performed in 93.4% of patients in different territories. Overall, vasculitis was identified in 80.3% (97.3% in MPA and 61.8% in GPA) of patients. CONCLUSIONS: The identification of GPA presentations associated with MPO-ANCA and awareness of risk factors for relapse and mortality are important to guide proper therapeutic strategies in AAV patients. Biopsies of different affected territories should be pursued in difficult-to-diagnose patients based on their significant diagnostic yield.

miR-146a and miR-146b regulate the expression of ICAM-1 in giant cell arteritis.

Giant cell arteritis (GCA) is an inflammatory disease of large/medium-sized arteries. MiRNAs are small, non-coding RNAs that inhibit gene expression at post-transcriptional level. Several miRNAs have been shown to be dysregulated in temporal artery biopsies (TABs) from GCA patients, but their role is unknown. The aims of the present work were: to gain insight into the link between inflammation and miRNA up-regulation in GCA; to identify the role of miR-146a and miR-146b. Primary cultures from TABs were treated with IL-1ß, IL-6, soluble IL-6R (sIL6R), IL-17, IL-22, IFNγ, LPS and PolyIC. Correlations between cytokine mRNA and miRNA levels were determined in inflamed TABs. Primary cultures from TABs, human aortic endothelial and smooth muscle cells and ex-vivo TAB sections were transfected with synthetic miR-146a and miR-146b to mimic miRNA activities. Cell viability, target gene expression, cytokine levels in culture supernatants were assayed. Treatment of primary cultures from TABs with IL-1ß and IL-17 increased miR-146a expression while IL-1ß, IL-6+sIL6R and IFNγ increased miR-146b expression. IFNγ and IL-1ß mRNA levels correlated with miR-146a/b levels. Following transfection, cell viability decreased only in primary cultures from TABs. Moreover, transfection of miR-146a/b mimics increased ICAM-1 gene expression and production of the soluble form of ICAM-1 by primary cultures from TABs and by ex-vivo TABs. ICAM-1 expression was higher in inflamed than normal TABs and ICAM-1 levels correlated with miR-146a/b levels. Expression of miR-146a and miR-146b in GCA appeared to be driven by inflammatory cytokines (e.g. IL-1ß, IFNγ). miR-146a and miR-146b seem responsible for the increase of soluble ICAM-1.

[The euthanasia law and professional experiences: tensions in clinical practice]. / La ley de eutanasia y experiencias profesionales: tensiones en la práctica clínica.

OBJECTIVE: To analyze the process of assisted death provision in Catalonia and identify the main tensions, difficulties, and/or sources of discomfort related to professional practice. METHOD: A qualitative study was conducted based on interviews (n=29) and focus groups (n=19) with professionals who participated in the euthanasia process. The selection of participants combined the snowball and maximization of variability procedures, taking into account the variables of professional profile, setting, gender, age and territoriality. Intentional and theoretical sampling process. RESULTS: The assisted death process is divided into four main moments: 1) reception of the request, 2) medical-bureaucratic procedure, 3) the actual procedure, and 4) closure. At each of these moments, difficulties arise that can be a source of discomfort and have to do with the limits and tensions between the legal and moral, the conception of one's own professional role, the lack of recognition of some professional roles, stress and overload, the lack of formal and informal support, and the relationship with the patient and his/her family. The bureaucratic-administrative stress derived from a protective law, with both prior and subsequent verifying control, stands out, given that it stresses the professionals immersed in a healthcare system already under high pressure after budget cuts and the COVID-19 epidemic. CONCLUSIONS: Throughout the assisted death process, the sources of distress are diverse and of a psychological, psychosocial, and structural nature. These results may lead to interventions for psychological and peer support, information, training, institutional involvement, and burden reduction.

Relationships between Patient-Reported Outcome Measures and Clinical Measures in Naïve Neovascular Age-Related Macular Degeneration Patients Treated with Intravitreal Ranibizumab.

Our objective was to evaluate changes in patient-reported outcome measures using the NEI-VFQ 25 questionnaire during a treat and extend regimen in naive neovascular Age-Related Macular Degeneration patients, and its correlation with anatomical and functional data. We conducted a prospective observational study. Patients underwent a treat and extend regimen with intravitreal ranibizumab for neovascular Age-Related Macular Degeneration. Initial response was evaluated at 4th month, and subsequently in every follow-up visit. If a clinical response was achieved, the injection interval was extended in two-week increments, up to a maximum of 12 weeks. Quality of life was assessed using the NEI-VFQ 25 questionnaire at baseline, 4th months, and 12th months. Patients were categorized as good or poor responders based on Best corrected visual acuity, central foveal thickness, intraretinal fluid, or subretinal fluid. Treatment with ranibizumab led to a significant improvement in quality of life, with a mean increase in NEI-VFQ 25 score of 4.27 points in the 12th month. No significant differences in improvement were observed between good and poor responders. Quality of life scores in neovascular Age-Related Macular Degeneration patients improved with intravitreal treatment regardless of the clinical response. The early response following the loading phase could indicate better quality of life after one year of treatment, with Best corrected visual acuity being the clinical parameter with the greatest influence on quality of life.

360° approach to the patient with mite allergy: from scientific evidence to clinical practice.

In the recent years, several important advances have been made in the diagnosis of allergy using molecular techniques. The aetiological diagnosis of allergy using molecular components of allergens allows a more precise definition of the patient's IgE repertoire. Precision medicine is a structural model aimed at personalising healthcare and places the patient at the centre of the specialist's decision-making process. To this end, an accurate characterisation of the external exposome at a molecular level and their putative role as clinically relevant allergens is essential to elucidate the phenotypic diversity of atopic disease, with a view to personalising diagnosis and therapy. It has been proposed a decision algorithm, the Top-Down approach, where the clinical history is set first and is followed by the use of skin tests or specific IgE techniques, which facilitates the clinicians to make decisions. The therapeutic intervention driven by the standard diagnostic approach, but supported by these innovative tools, can lead to a better phenotyping of highly complex patients, and a more appropriate prescription of AIT. To this end, the allergen extracts used for diagnosis require to be of proven quality and contain the most relevant allergens. Likewise, allergen vaccines must gather efficacy, safety, duration, and patient compliance, hence the demand for new vaccines to overcome these drawbacks.

Maternal and fetal outcomes of pregnancy in women with primary systemic vasculitis: A single-center cohort study of 20 patients and 30 pregnancies.

OBJECTIVES: To analyze pregnancy outcomes of patients with primary systemic vasculitis followed in a third-level referral center. METHODS: Retrospective cohort study of all pregnant women with systemic vasculitis followed between 2009 and 2022 at the High-Risk Pregnancy Clinic of the Department of Systemic Autoimmune Diseases of the Hospital Clínic, Barcelona. RESULTS: Twenty women with primary vasculitis were identified, with a total of 30 pregnancies. Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (n = 7) and Behçet disease (n = 4) were the most frequent types of vasculitis. All women had the diagnosis of vasculitis before pregnancy, with a median time between disease diagnosis and pregnancy of 5.8 years (range: 2 months-29 years). Most were in remission at conception (76.7 %). During pregnancy, a vasculitis flare occurred in 4 (13.3 %) patients (one each with Takayasu arteritis, eosinophilic granulomatosis with polyangiitis [EGPA], IgA vasculitis [IgAV], and Behçet disease [BD]). Four (16.7 %) of the successful pregnancies had post-partum relapses (one each with EGPA, granulomatosis with polyangiitis, IgAV, and BD). Eighty percent of pregnancies resulted in live babies. In four cases (13.3 %), medical termination of pregnancy was decided, considering the mother or baby health risk. There were two spontaneous miscarriages, and no stillbirths or neonatal deaths. Preeclampsia was the most frequent maternal complication (25 %). Newborns were preterm in 24 % and low birthweight in 20 % of cases. No maternal deaths occurred. CONCLUSIONS: This cohort study shows that vasculitis relapses during pregnancy and post-partum, together with other pregnancy complications, occur in a considerable number of patients with systemic vasculitides, although a final good pregnancy outcome can be expected in most cases. These findings emphasize the convenience of managing these special situations in expert reference centers.

Knowledge about the best practice guidelines in the nursing degree: A non-randomized post-test design.

AIM: To compare knowledge of Nursing Degree students about Best Practice Guidelines when there are included as teaching content in a subject vs knowledge through having the usual internship experience without teaching specific guidelines contents. DESIGN: Non-randomized post-test-only design with a comparison group. METHODS: 143 students of the nursing degree at the Autonomous University of Barcelona were recruited. The intervention group received a classroom training in three Best Practice Guidelines with Problem-Based Learning methodology. The comparison group only attended internship, without specific guidelines contents. Knowledge was evaluated with an ad hoc post intervention questionnaire. The information was collected between 2016 and 2018. RESULTS: The average score of knowledge was low, 5.1 out of 10, and differs between guides. The best results were obtained by the students with internships and that had consulted the guides on some occasions. Synchronized effort and leadership in Academia and Healthcare are needed to favour evidence-based practice. The combination of the consultation of the Best Practice Guidelines in theoretical learning combined with the practice, increases the knowledge of the Best Practice Guidelines and will favour the implementation of evidence-based practice. Some students were involved in questionnaire design.

The Effect of Systemic Parameters and Baseline Characteristics in Short-Term Response Analysis with Intravitreal Ranibizumab in Treatment-Naive Patients with Neovascular Age-Related Macular Degeneration.

Anti-vascular endothelial growth factor drugs keep being the main therapy for neovascular age-related macular degeneration (AMD). Possible predictive parameters (demographic, biochemical and/or inflammatory) could anticipate short-term treatment response with ranibizumab. 46 treatment-naive patients were included in a prospective observational study. They underwent three monthly injections of intravitreal ranibizumab for neovascular AMD and the clinical examination was made at baseline and one month after the third injection. Demographic characteristics, co-morbidities and concomitant treatments were recorded at the baseline visit. Biochemical parameters, complete blood count and inflammation biomarkers were also measured at these times. Uric Acid was found to be statistically significant with a one-point difference between good and poor responders in both basal and treated patients, but only in basal parameters was statistical significance reached (p = 0.007 vs. p = 0.071 in treated patients). Cholesterol and inflammatory parameters such as white blood cell count and neutrophils were significantly reduced over time when treated with intravitreal ranibizumab. On the other hand, women seemed to have a worse prognosis for short-term response to intravitreal ranibizumab treatment. Uric acid may help identify possible non-responders before initial treatment with ranibizumab, and cholesterol and white blood cells could be good candidates to monitor short-term response to ranibizumab treatment.

Treat-to-target recommendations in giant cell arteritis and polymyalgia rheumatica.

OBJECTIVES: To develop treat-to-target (T2T) recommendations in giant cell arteritis (GCA) and polymyalgia rheumatica (PMR). METHODS: A systematic literature review was conducted to retrieve data on treatment targets and outcomes in GCA/PMR as well as to identify the evidence for the effectiveness of a T2T-based management approach in these diseases. Based on evidence and expert opinion, the task force (29 participants from 10 countries consisting of physicians, a healthcare professional and a patient) developed recommendations, with consensus obtained through voting. The final level of agreement was provided anonymously. RESULTS: Five overarching principles and six-specific recommendations were formulated. Management of GCA and PMR should be based on shared decisions between patient and physician recognising the need for urgent treatment of GCA to avoid ischaemic complications, and it should aim at maximising health-related quality of life in both diseases. The treatment targets are achievement and maintenance of remission, as well as prevention of tissue ischaemia and vascular damage. Comorbidities need to be considered when assessing disease activity and selecting treatment. CONCLUSION: These are the first T2T recommendations for GCA and PMR. Treatment targets, as well as strategies to assess, achieve and maintain these targets have been defined. The research agenda highlights the gaps in evidence and the need for future research.

Single-cell transcriptomic profiling reveals a pathogenic role of cytotoxic CD4+ T cells in giant cell arteritis.

Giant cell arteritis (GCA) is a systemic vasculitis mediated by an aberrant immunological response against the blood vessel wall. Although the pathogenic mechanisms that drive GCA have not yet been elucidated, there is strong evidence that CD4+ T cells are key drivers of the inflammatory process occurring in this vasculitis. The aim of this study was to further delineate the role of CD4+ T cells in GCA by applying single-cell RNA sequencing and T cell receptor (TCR) repertoire profiling to 114.799 circulating CD4+ T cells from eight GCA patients in two different clinical states, active and in remission, and eight healthy controls. Our results revealed an expansion of cytotoxic CD4+ T lymphocytes (CTLs) in active GCA patients, which expressed higher levels of cytotoxic and chemotactic genes when compared to patients in remission and controls. Accordingly, differentially expressed genes in CTLs of active patients were enriched in pathways related to granzyme-mediated apoptosis, inflammation, and the recruitment of different immune cells, suggesting a role of this cell type in the inflammatory and vascular remodelling processes occurring in GCA. CTLs also exhibited a higher clonal expansion in active patients with respect to those in remission. Drug repurposing analysis prioritized maraviroc, which targeted CTLs, as potentially repositionable for this vasculitis. In addition, effector regulatory T cells (Tregs) were decreased in GCA and showed lower expression of genes involved in their suppressive activity. These findings provide further insights into the pathogenic role of CD4+ T cells in GCA and suggest targeting CTLs as a potential therapeutic option.