Senescent cells in giant cell arteritis display an inflammatory phenotype participating in tissue injury via IL-6-dependent pathways.

OBJECTIVES: Age is the strongest risk factor of giant cell arteritis (GCA), implying a possible pathogenetic role of cellular senescence. To address this question, we applied an established senescence specific multimarker algorithm in temporal artery biopsies (TABs) of GCA patients. METHODS: 75(+) TABs from GCA patients, 22(-) TABs from polymyalgia rheumatica (PMR) patients and 10(-) TABs from non-GCA/non-PMR patients were retrospectively retrieved and analysed. Synovial tissue specimens from patients with inflammatory arthritis and aorta tissue were used as disease control samples. Senescent cells and their histological origin were identified with specific cellular markers; IL-6 and MMP-9 were investigated as components of the senescent associated secretory phenotype by triple costaining. GCA or PMR artery culture supernatants were applied to fibroblasts, HUVECs and monocytes with or without IL-6R blocking agent to explore the induction of IL-6-associated cellular senescence. RESULTS: Senescent cells were present in GCA arteries at higher proportion compared with PMR (9.50% vs 2.66%, respectively, p<0.0001) and were mainly originated from fibroblasts, macrophages and endothelial cells. IL-6 was expressed by senescent fibroblasts, and macrophages while MMP-9 by senescent fibroblasts only. IL-6(+) senescent cells were associated with the extension of vascular inflammation (transmural inflammation vs adventitia limited disease: 10.02% vs 4.37%, respectively, p<0.0001). GCA but not PMR artery culture supernatant could induce IL-6-associated senescence that was partially inhibited by IL-6R blockade. CONCLUSIONS: Senescent cells with inflammatory phenotype are present in GCA arteries and are associated with the tissue inflammatory bulk, suggesting a potential implication in disease pathogenesis.

Treatment of giant cell arteritis with ultra-short glucocorticoids and tocilizumab: results from the extension of the TOPAZIO study.

OBJECTIVES: To assess the maintenance of efficacy of one year of tocilizumab (TCZ) monotherapy after its discontinuation in large vessel-GCA (LV-GCA). METHODS: 17 patients with active LV-GCA were previously treated with 3 boluses of intravenous methylprednisone and weekly subcutaneous TCZ in monotherapy for 52 weeks. Patients in relapse-free clinical remission at week 52 discontinued TCZ and entered part two, which was a 26-week observational follow-up period. PET/CT was performed in all patients at the end of the 26-week observational period (week 78). End points were the variation in PET vascular activity score (PETVAS) at week 78 compared with baseline and with week 52, and the proportion of patients with relapse-free clinical remission at week 78 and at the end of the follow-up. RESULTS: Compared with baseline, a significant reduction in PETVAS was observed at week 78, mean (95% CI) change -6.6 (-9.5 to -3.7). However, compared with week 52, PETVAS significantly increase 6 months after TCZ discontinuation (week 78), mean (95% CI) change 4.6 (0.7-8.5). The proportion of patients with relapse-free clinical remission at weeks 78 and at the end of the follow-up (median time from TCZ discontinuation 148 weeks) was 11/17 (65%, 95% CI 38-86) and 8/17 (47%, 95% CI 23-72), respectively. Age and sex-adjusted HR (95% CI) for each unit increase of PETVAS indicating subsequent relapse was 1.36 (0.92-2.00). CONCLUSIONS: One year of TCZ monotherapy was effective in maintaining drug-free clinical remission in LV-GCA. Changes in PETVAS early after TCZ discontinuation may predict subsequent relapses. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov, NCT05394909.

Identification of two autoantigens recognised by circulating autoantibodies as potential biomarkers for diagnosing giant cell arteritis.

OBJECTIVES: Giant cell arteritis (GCA) is a common vasculitis affecting patients aged 50 and older. GCA leads to chronic inflammation of large/medium-sized vessel walls with complications such as permanent vision loss and risk of stroke and aortic aneurysms. Early diagnosis is crucial and relies on temporal artery biopsy (TAB) and ultrasound imaging of temporal and axillary arteries. However, these methods have limitations. Serum biomarkers as autoantibodies have been reported but with inconclusive data for their use in the clinical setting. Additionally, C-reactive protein and erythrocyte sedimentation rate are non-specific and limited in reflecting disease activity, particularly in patients treated with IL-6 inhibitors. This study aimed to identify serum autoantibodies as new diagnostic biomarkers for GCA using a human protein array. METHODS: One commercial and one proprietary human protein array were used for antibody profiling of sera from patients with GCA (n=55), Takayasu (TAK n=7), and Healthy Controls (HC n=28). The identified candidate autoantigens were purified and tested for specific autoantibodies by ELISA. RESULTS: Antibodies against two proteins, VSIG10L (V-Set and Immunoglobulin Domain Containing 10 Like) and DCBLD1 (discoidin), were identified and found to be associated with GCA, with an overall prevalence of 43-57%, respectively, and high specificity as individual antibodies. A control series of TAK sera tested negative. CONCLUSIONS: Detecting GCA-specific autoantibodies may offer a new, non-invasive tool for improving our diagnostic power in GCA. Even though cell-mediated immune responses are crucial for GCA pathogenesis, this finding opens the way for investigating the additional role of humoral immune responses in the disease.

Systemic vasculitis: one year in review 2024.

Systemic vasculitides comprise a collection of rare and heterogeneous disorders capable of impacting any organ and system, posing a considerable burden of mortality and comorbidity. As with previous annual reviews of this series, this review will offer a critical overview of the latest literature on pathogenesis, biomarkers, and treatment options in both small- and large-vessel vasculitis.

C-reactive protein gene polymorphisms influence susceptibility and outcomes of biopsy-proven giant cell arteritis in Italian patients.

OBJECTIVES: To investigate potential associations between the two functional C-reactive protein (CRP) gene polymorphisms at position 3872C>T (rs1205) and 4741G>C (rs3093068) and susceptibility, clinical expression, laboratory and pathological findings, and outcomes of giant cell arteritis (GCA) in a Nothern Italian population. METHODS: One hundred and seventy Italian patients with biopsy-proven GCA resident in Reggio Emilia area, Italy, and 200 healthy controls from the same geographic area were genotyped for rs1205 and rs3093068 CRP gene polymorphisms by molecular methods. The patients were subgrouped on the basis of the presence or absence of clinical manifestations, histological and laboratory findings, and outcomes. RESULTS: The distribution of rs1205 genotype was significantly different between GCA patients and controls (p=0.018). Homozygosity for T allele was significantly more frequent in GCA patients compared to controls [p=0.006; odds ratio (OR): 2.28 (95% CI: 1.1, 4.8)]. The distribution of rs3093068 genotype differed significantly between GCA patients and controls (p=0.010). Allele C and the carriers of the C allele (C/C+C/G) of rs3093068 genotype were significantly less frequent in GCA patients compared to controls [p=0.002, OR: 0.39 (95% CI: 0.24-0.73); p=0.002, OR: 0.35 (95% CI: 0.17-0.70), respectively]. No significant associations were found between the two polymorphisms and baseline clinical manifestations. The carriers of the allele C of rs3093068 genotype had significantly higher CRP values at diagnosis (13.2±5.0 vs. 8.3±6.0 mg/dl, p=0.007). Homozygosity for T allele of rs1205 genotype had a significantly more frequent eosinophil infiltration of the temporal artery wall (21.4% vs. 6.0%) (p=0.010, OR 4.28;1.31-13.98) than patients carrying the allele C. Carriers of the allele T of rs1205 genotype had lower glucocorticoid (GC) treatment duration (p=0.041), lower cumulative total GC dose (p=0.017), and higher prevalence of long-term remission (p=0.024). CONCLUSIONS: CRP gene rs1205 and rs3093068 polymorphisms influence GCA susceptibility and its outcomes.

Pros and cons of TNF inhibitors and tocilizumab in the treatment of large-vessel vasculitis.

Large-vessel vasculitides (LVVs) include giant cell arteritis (GCA) and Takayasu's arteritis (TAK). Even if similar, these two entities differ in terms of treatment and outcomes.High doses of glucocorticoids (GCs) are still the first choice for the treatment of both conditions. However, adjunctive therapies are recommended in selected patients in order to decrease the risk of relapse and the amount of side effects related to GCs. Tumour necrosis factor α inhibitors (TNFis) and tocilizumab (TCZ) are used for the treatment of LVVs, with some differences. In GCA, TCZ has been proved to be effective and safe in inducing remission with some open questions still remaining, whereas data about TNFis are scarce and non-conclusive. On the contrary, in TAK either TNFis or TCZ seem to be able to control symptoms and angiographic progression in refractory forms.However, their place in the management of treatment must still be clarified, and as a result the American College of Rheumatology and EULAR guidelines slightly differ in the recommendations about when and what treatment to start. Thus, the aim of this review is to look at the evidence on the use of TNFis and TCZ in LVVs, outlining the pros and cons of both therapies.

Environmental triggers for connective tissue disease: the case of COVID-19 associated with dermatomyositis-specific autoantibodies.

PURPOSE OF REVIEW: The aim of the present review is to analyze the link between autoimmune diseases and environmental factors, in particular severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection (COVID-19) as it shares numerous features with the interstitial lung disease associated with connective tissue diseases positive for rare autoantibodies directed at highly specific autoantigens (i.e., MDA5 and RIG1) among the intracellular sensors of SARS-CoV-2 in the innate response against viruses. RECENT FINDINGS: As shown in recent publications and in our original data, specific autoantibodies may be functionally relevant to COVID-19 infection. We evaluated sera from 35 hospitalized patients with COVID-19 to identify antinuclear antibodies and autoantibodies directed against specific antigenic targets, and we identified anti-nuclear antibodies (ANA) in 20/35 of patients with COVID-19 (57%), in patients with need for supplemental oxygen (90% vs. 20% in ANA-negative cases; P < 0.0001). In 7/35 COVID-19 sera, we detected anti-MJ/NXP2 (n = 3), anti-RIG1 (n = 2), anti-Scl-70/TOPO1 (n = 1), and anti-MDA5 (n = 1), overall associated with a significantly worse pulmonary involvement at lung computerized tomography scans. Eleven (31%) patients were positive for antibodies against the E2/E3 subunits of mitochondrial pyruvate dehydrogenase complex. SUMMARY: Viral infections such as COVID-19 are associated with ANA and autoantibodies directed toward antiviral signaling antigens in particular in patients with worse pulmonary involvement.

Ultrasound Examination of Common Carotid Adventitial Thickness Can Differentiate Takayasu Arteritis and Large Vessel Giant Cell Arteritis.

Pathological studies have demonstrated that the adventitial layer is markedly thickened in Takayasu (TAK) as compared to large vessel giant cell arteritis (LV-GCA). An ultrasound (US) examination of the arterial vessels allows the determination of intima media thickness (IMT) and of adventitial layer thickness (extra media thickness (EMT)). No previous study has evaluated if there are differences in EMT thickness between TAK and LV-GCA. In this cross-sectional retrospective study of stored ultrasound (US) imaging, we have compared common carotid artery (CCA) EMT and IMT in a series of consecutive TAK and LV-GCA patients. US examination CCA IMT and EMT were significantly higher in TAK as compared to LV-GCA. With ROC curve analysis, we have found that an EMT > 0.76 mm has high sensitivity and specificity for TAK CCA examination. The percentage of CCA at EMT > 0.76 mm and the total arterial wall thickening were significantly higher in TAK group examinations. EMT thickness correlated with disease duration and IMT in the TAK group, as well as with the IMT and ESR values in the LV-GCA group. Upon multivariate logistic regression analysis, factors independently associated with TAK CCA were EMT > 0.76 mm and age. No significant variation in IMT and EMT could be demonstrated in subsequent US CCA examinations.

Development of the Takayasu Arteritis Integrated Disease Activity Index.

OBJECTIVE: Accurate clinical assessment of disease activity in Takayasu arteritis (TAK) can be challenging. 18F-fluorodeoxyglucose-positron emission tomography (FDG-PET) can directly measure vascular inflammation. This study details the development of a new type of disease activity index called the Takayasu's Arteritis Integrated Disease Activity Index (TAIDAI). METHODS: Clinical symptoms for TAIDAI were identified from a literature review. Each symptom was paired with FDG-PET findings in corresponding arterial territories. Constitutional symptoms were paired with acute phase reactant levels. One point was given for each clinical symptom paired with supporting FDG-PET or laboratory abnormalities and summed into the TAIDAI score. A TAIDAI of ≥1 defined active disease. To assess performance of TAIDAI, face validity, content validity, and sensitivity to change were evaluated within a prospective observational cohort study of patients with TAK. RESULTS: Seventeen clinical symptoms were paired with imaging or laboratory abnormalities. In a cohort of 96 patients contributing 204 study visits, TAIDAI showed excellent sensitivity (96.3%) and good specificity (79.2%) compared to physician's clinical assessment. TAIDAI significantly correlated with physician global assessment, PET Vascular Activity Score, patient global assessment, and acute phase reactant levels. In patients treated with either tumor necrosis factor inhibitors or tocilizumab, a TAIDAI of 0 was achieved in 21 (91%) of 23 patients who met a predefined definition of clinical response. CONCLUSION: TAIDAI is new type of disease activity index in TAK in which clinical symptoms are integrated with specific laboratory and imaging findings. TAIDAI should be validated in future randomized controlled trials in TAK.

Eosinophilic giant cell arteritis: A different subset of disease?

OBJECTIVES: To describe the clinical findings, response to therapy and course of patients with transmural eosinophilic infiltration at temporal artery biopsy (TAB). METHODS: The study consisted of a retrospective cohort of 254 consecutive GCA patients with evidence of transmural inflammation at TAB seen at the Santa Maria Nuova Hospital over a 28-year period. The findings of the 22 patients with eosinophilic infiltration (≥ 20 eosinophils/hpf) at TAB were compared with those of 232 patients without. Among these 232 patients, we sampled 42 GCA patients matched for age, sex and follow-up duration to the 22 with eosinophilic infiltration, to compare allergic manifestations. RESULTS: GCA patients with eosinophilic infiltration compared to those without presented more frequently cranial symptoms (p = 0.052), headaches (p = 0.005), abnormalities of TAs at physical examination (p = 0.045), jaw claudication (p = 0.024), and systemic manifestations (p = 0.016) and had higher CRP levels at diagnosis (p = 0.001). Regarding histological lesions, a severe transmural inflammation, laminar necrosis and intraluminal acute thrombosis were more frequently observed in patients with eosinophilic infiltration (p = 0.066, p < 0.001, and p = 0.010, respectively). Long-term remission and flares were similar in the two groups. When 21 GCA patients with eosinophilic infiltration were compared to 42 without, blood eosinophilic counts at diagnosis were normal and no patients had evidence or developed allergic manifestations and/or clinical findings of systemic necrotizing vasculitis. CONCLUSION: Patients with transmural eosinophilic infiltration represent a subset of GCA with cranial disease and more severe inflammation.

Effectiveness and safety of a 26-week taper regimen of glucocorticoid in GCA patients: Results from a prospective cohort study.

OBJECTIVES: To assess the effectiveness and safety of the 26-week tapering regimen of glucocorticoids (GC) used in the GiACTA trial in a prospective cohort of treatment-naive, biopsy-proven GCA patients. METHODS: Patients with a new diagnosis of biopsy-proven GCA enrolled in the GC arm of the START project (molecular stratification of patients with GCA to tailor GC and tocilizumab therapy) were included. All patients were treated with the 26-week taper regimen of GC used in the GiACTA trial. The primary endpoint was the rate of relapse-free remission at week 52. The secondary endpoints were the proportion of patients with incident aortic damage, cumulative GC doses and GC-related adverse events (AE). RESULTS: 22 patients were included between December 2018 and February 2022. At week 52, 10 patients (45 %, 95 % CI 24-68) were in relapse-free remission. After a median (IQR) follow-up of 35 (22-40) months, 7 patients (32 %, 95 % CI 14-55) were in relapse-free remission. 18 patients with baseline large-vessel imaging underwent CT angiography at the end of the follow-up. No patients had evidence of new aortic dilation, significant progression of aortic damage or large vessel stenosis. 15/22 patients (68 %) had at least one relapse during follow-up. No patients developed visual or cerebrovascular manifestations during relapses. 15/22 (68 %) patients had at least one GC-related AE. CONCLUSIONS: A 26 week taper regimen of GC was effective and safe in inducing and maintaining remission in a sizeable proportion of newly diagnosed GCA patients. However, the frequency of GC-related adverse events was high.

Steroid-sparing agents in polymyalgia rheumatica: how will they fit into the treatment paradigm?

INTRODUCTION: Polymyalgia rheumatica is a common inflammatory rheumatic disease in subjects aged 50 years or older and classically presents with shoulder and/or pelvic girdle pain and prolonged morning stiffness. Glucocorticoids represent the standard of treatment; glucocorticoid therapy is usually required for 1-2 years and often results in significant glucocorticoid-related side effects, especially in the elderly. AREAS COVERED: In this review, we aimed to provide a comprehensive overview of the management of polymyalgia rheumatica, with a particular focus on adjunctive therapies to the standard glucocorticoid treatment. EXPERT OPINION: Given the high frequency of disease relapses (one-third of patients) and the adverse events related to prolonged glucocorticoid use, the need for glucocorticoid-sparing agents remains an important issue in the management of polymyalgia rheumatica. In selected patients, who are at risk for glucocorticoid-related side effects or in those with glucocorticoid-refractory disease, the addition of a glucocorticoid-sparing agent, either a synthetic or biologic disease-modifying anti-rheumatic drug, may represent a reasonable and effective therapeutic approach.