Tissue and serum markers of inflammation during the follow-up of patients with giant-cell arteritis--a prospective longitudinal study

Outcome of a glucocorticoid discontinuation regimen in patients with inactive systemic sclerosis

Glucocorticoids (GC) are widely used to treat systemic sclerosis (SSc). The lack of efficacy data and patient/physician concerns may prompt therapy discontinuation. The aim of this study is to identify factors hampering GC discontinuation in patients with stable disease on oral GC for longer than 12 months. Consecutive patients fulfilling the 2013 ACR/EULAR criteria for SSc and with stable disease were prescribed a slow tapering GC regimen to achieve discontinuation. At study entry and 6 months later (T6), patients were assessed for disease activity and severity. Moreover, the Short-Form-36; the Health Assessment Questionnaire Disability Index (HAQ-DI); and visual analog scales for fatigue, pain, and general health were completed. Reasons for stopping the discontinuation regimen were recorded. Forty-eight patients (46 females, 9 diffuse SSc), with a mean ± SD age of 56±14 years and a median disease duration of 10 years (range 2-22), were enrolled. The median daily GC dose was 5 mg (range 5-10; all patients treated with prednisone). At T6, 33 (68.7 %) patients had discontinued GC. The remaining 15 patients could not discontinue GC because of arthralgia in eight, arthritis in two, puffy fingers in two, increased creatine-kinase in two, and bursitis in one patient. At multiple logistic analysis, a higher baseline HAQ-DI was the only independent factor associated with GC need (OR 2.98, 95 % CI 1.20-7.41; p = 0.01). About one third of SSc patients did not achieve a GC-free regimen. Disability as assessed by HAQ-DI was the leading factor hindering GC discontinuation. A low HAQ-DI score can identify candidates for GC discontinuation.

Identification of IL-23p19 as an endothelial proinflammatory peptide that promotes gp130-STAT3 signaling

Interleukin-23 (IL-23), a heterodimeric cytokine composed of the unique p19 peptide (IL-23p19) and a peptide called IL-12p40, which is shared with IL-12, is implicated in Crohn's disease, rheumatoid arthritis, psoriasis, and other immune-mediated inflammatory diseases. Endothelial cells produce the IL-23p19 peptide in the absence of the IL-12p40 chain and thus do not make heterodimeric IL-23. We found that intercellular IL-23p19 increased the cell surface abundances of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) on endothelial cells, which enhanced the attachment of leukocytes and increased their transendothelial migration. Intracellular p19 associated with the cytokine receptor subunit gp130 and stimulated the gp130-dependent activation of signal transducer and activator of transcription 3 (STAT3) signaling. Proinflammatory factors promoted the generation of IL-23p19 in endothelial cells. The adventitial capillaries of inflamed temporal arteries in patients with giant-cell arteritis (GCA) had endothelial p19 protein associated with gp130, but did not contain the IL-12p40 chain. Because adventitial capillaries are essential for the entry of inflammatory cells into arterial walls, these data suggest that p19 may contribute to GCA disease and could represent a therapeutic target. Our results provide evidence that IL-23p19 is a previously unrecognized endothelial proinflammatory peptide that promotes leukocyte transendothelial migration, advancing our current understanding of the complexities of inflammatory responses.

Description and Validation of Histological Patterns and Proposal of a Dynamic Model of Inflammatory Infiltration in Giant-cell Arteritis

The extent of inflammatory infiltrates in arteries from patients with giant-cell arteritis (GCA) have been described using different terms and definitions. Studies investigating the relationship between GCA histological features and clinical manifestations have produced controversial results. The aims of this study were to characterize and validate histological patterns in temporal artery biopsies (TABs) from GCA patients, to explore additional histological features, including the coexistence of different patterns, and also to investigate the relationship of the inflammatory patterns with clinical and laboratory features.We performed histological examination of TAB from patients with GCA consecutively diagnosed between 1992 and 2012. Patterns of inflammation were defined according to the extent and distribution of inflammatory infiltrates within the artery. Clinical and laboratory variables were recorded. Two external investigators underwent a focused, one-day training session and then independently scored 77 cases. Quadratic-weighted kappa was calculated.TAB from 285 patients (200 female/85 male) were evaluated. Four histological inflammatory patterns were distinguished: 1 - adventitial (n = 16); 2 - adventitial invasive: adventitial involvement with some extension to the muscular layer (n = 21); 3 - concentric bilayer: adventitial and intimal involvement with media layer preservation (n = 52); and 4 - panarteritic (n = 196). Skip lesions were observed in 10% and coexistence of various patterns in 43%. Raw agreement of each external scorer with the gold-standard was 82% and 77% (55% and 46% agreement expected from chance); kappa = 0.82 (95% confidence interval [CI] 0.70-0.95) and 0.79 (95% CI 0.68-0.91). Although abnormalities on temporal artery palpation and the presence of jaw claudication and scalp tenderness tended to occur more frequently in patients with arteries depicting more extensive inflammation, no statistically significant correlations were found between histological patterns and clinical features or laboratory findings.In conclusion, we have described and validated 4 histological patterns. The presence of different coexisting patterns likely reflects sequential steps in the progression of inflammation and injury. No clear relationship was found between these patterns and clinical or laboratory findings. However, several cranial manifestations tended to occur more often in patients with temporal arteries exhibiting panarteritic inflammation. This validated score system may be useful to standardize stratification of histological severity for immunopathology biomarker studies or correlation with imaging.

Blocking interferon γ reduces expression of chemokines CXCL9, CXCL10 and CXCL11 and decreases macrophage infiltration in ex vivo cultured arteries from patients with giant cell arteritis

Background

Interferon γ (IFNγ) is considered a seminal cytokine in the pathogenesis of giant cell arteritis (GCA), but its functional role has not been investigated. We explored changes in infiltrating cells and biomarkers elicited by blocking IFNγ with a neutralising monoclonal antibody, A6, in temporal arteries from patients with GCA.

Methods

Temporal arteries from 34 patients with GCA (positive histology) and 21 controls were cultured on 3D matrix (Matrigel) and exposed to A6 or recombinant IFNγ. Changes in gene/protein expression were measured by qRT-PCR/western blot or immunoassay. Changes in infiltrating cells were assessed by immunohistochemistry/immunofluorescence. Chemotaxis/adhesion assays were performed with temporal artery-derived vascular smooth muscle cells (VSMCs) and peripheral blood mononuclear cells (PBMCs).

Results

Blocking endogenous IFNγ with A6 abrogated STAT-1 phosphorylation in cultured GCA arteries. Furthermore, selective reduction in CXCL9, CXCL10 and CXCL11 chemokine expression was observed along with reduction in infiltrating CD68 macrophages. Adding IFNγ elicited consistent opposite effects. IFNγ induced CXCL9, CXCL10, CXCL11, CCL2 and intracellular adhesion molecule-1 expression by cultured VSMC, resulting in increased PBMC chemotaxis/adhesion. Spontaneous expression of chemokines was higher in VSMC isolated from GCA-involved arteries than in those obtained from controls. Incubation of IFNγ-treated control arteries with PBMC resulted in adhesion/infiltration by CD68 macrophages, which did not occur in untreated arteries.

Conclusions

Our ex vivo system suggests that IFNγ may play an important role in the recruitment of macrophages in GCA by inducing production of specific chemokines and adhesion molecules. Vascular wall components (ie, VSMC) are mediators of these functions and may facilitate progression of inflammatory infiltrates through the vessel wall.

Outcome assessment in Takayasu arteritis

Takayasu arteritis (TAK) is a systemic granulomatous large-vessel vasculitis with a phenotype that overlaps with GCA and defined by the 1993 and 2012 Chapel Hill Consensus Conference statements. However, the diagnosis of TAK is often delayed since TAK patients may be asymptomatic or have non-specific symptoms. Once a diagnosis is made, it is difficult to judge remission or recurrence since there are no reliable assessment tools. With the availability of newer agents, such as cytokine blockade, which are being evaluated in GCA, there is the potential for real advances in TAK patient management. Without reliable assessment tools it will be difficult to introduce newer agents in an organized way or to optimally benefit patients in the future. In this article we review the use and performance of disease indicators in TAK clinical trials as a basis for the further development of assessment tools for this disease.

14-3-3 in Thoracic Aortic Aneurysms: Identification of a Novel Autoantigen in Large Vessel Vasculitis

OBJECTIVE

Large vessel vasculitides (LVV) are a group of autoimmune diseases characterized by injury to and anatomic modifications of large vessels, including the aorta and its branch vessels. Disease etiology is unknown. This study was undertaken to identify antigen targets within affected vessel walls in aortic root, ascending aorta, and aortic arch surgical specimens from patients with LVV, including giant cell arteritis, Takayasu arteritis, and isolated focal aortitis.

METHODS

Thoracic aortic aneurysm specimens and autologous blood were acquired from consenting patients who underwent aorta reconstruction procedures. Aorta proteins were extracted from both patients with LVV and age-, race-, and sex-matched disease controls with noninflammatory aneurysms. A total of 108 serum samples from patients with LVV, matched controls, and controls with antinuclear antibodies, different forms of vasculitis, or sepsis were tested.

RESULTS

Evaluation of 108 serum samples and 22 aortic tissue specimens showed that 78% of patients with LVV produced antibodies to 14-3-3 proteins in the aortic wall (93.7% specificity), whereas controls were less likely to do so (6.7% produced antibodies). LVV patient sera contained autoantibody sufficient to immunoprecipitate 14-3-3 protein(s) from aortic lysates. Three of 7 isoforms of 14-3-3 were found to be up-regulated in aorta specimens from patients with LVV, and 2 isoforms (ε and ζ) were found to be antigenic in LVV.

CONCLUSION

This is the first study to use sterile, snap-frozen thoracic aorta biopsy specimens to identify autoantigens in LVV. Our findings indicate that 78% of patients with LVV have antibody reactivity to 14-3-3 protein(s). The precise role of these antibodies and 14-3-3 proteins in LVV pathogenesis deserves further study.

Giant Cell Arteritis: Beyond Corticosteroids

Giant cell arteritis (GCA) is a large-vessel vasculitis predominantly affecting older people, with a peak incidence between 70 and 79 years of age. If untreated, ischaemic complications can be catastrophic for the patient, including blindness. We review the current treatment paradigms for this condition, the mainstay of which is immediate high-dose glucocorticoid therapy with a gradual dose tapering. Adverse events of glucocorticoid therapy are often observed after 12-24 months and corticosteroid-sparing adjuvant therapies are used in severe disease, multiple flares or patients at high risk of prolonged therapy. The current understanding of the pathogenesis of GCA is explored. This has informed the identification of new potential targets and approaches to treatment. Blockade of interleukin (IL)-6 (tocilizumab) and IL-1 (gevokizumab) are being evaluated in phase III clinical trials. It is hoped that improved risk stratification of organ damage and relapses will be developed using imaging and biomarkers, allowing for individualised treatment for patients; however, there remains further work to be done before this becomes a reality.

Advances in the diagnosis of large vessel vasculitis

The diagnosis of large-vessel vasculitis has experienced substantial improvement in recent years. While Takayasu arteritis diagnosis relies on imaging, the involvement of epicranial arteries by giant-cell arteritis facilitates histopathological confirmation. When appropriately performed temporal artery biopsy has high sensitivity and specificity. However, an optimal biopsy is not always achievable and, occasionally, the superficial temporal artery may not be involved. Imaging in its various modalities including colour-duplex ultrasonography, computed tomography angiography, magnetic resonance angiography and positron emission tomography, are emerging as important procedures for the diagnosis and assessment of disease extent in large-vessel vasculitis. Recent contributions to the better performance and interpretation of temporal artery biopsies as well as advances in imaging are the focus of the present review.

Giant cell arteritis: Current treatment and management

Glucocorticoids remain the cornerstone of medical therapy in giant cell arteritis (GCA) and should be started immediately to prevent severe consequences of the disease, such as blindness. However, glucocorticoid therapy leads to significant toxicity in over 80% of the patients. Various steroid-sparing agents have been tried, but robust scientific evidence of their efficacy and safety is still lacking. Tocilizumab, a monoclonal IL-6 receptor blocker, has shown promising results in a number of case series and is now being tested in a multi-centre randomized controlled trial. Other targeted treatments, such as the use of abatacept, are also now under investigation in GCA. The need for surgical treatment is rare and should ideally be performed in a quiescent phase of the disease. Not all patients follow the same course, but there are no valid biomarkers to assess therapy response. Monitoring of disease progress still relies on assessing clinical features and measuring inflammatory markers (C-reactive protein and erythrocyte sedimentation rate). Imaging techniques (e.g., ultrasound) are clearly important screening tools for aortic aneurysms and assessing patients with large-vessel involvement, but may also have an important role as biomarkers of disease activity over time or in response to therapy. Although GCA is the most common form of primary vasculitis, the optimal strategies for treatment and monitoring remain uncertain.

DNA methylation analysis of the temporal artery microenvironment in giant cell arteritis

OBJECTIVE

To investigate the inflammatory response in giant cell arteritis (GCA) by characterising the DNA methylation pattern within the temporal artery microenvironment.

METHODS

Twelve patients with non-equivocal histological evidence for GCA and 12 age-matched, sex-matched and ethnicity-matched controls with normal biopsies were studied. DNA was extracted from the affected portions of temporal artery tissue in patients with GCA and from histologically confirmed normal arteries in controls. Genome-wide DNA methylation status was evaluated using the Illumina Infinium HumanMethylation450 BeadChip Array. Differentially methylated loci between affected and unaffected arterial tissues were identified, and subsequent bioinformatic analysis performed. Immunohistochemistry was used to examine tissue expression patterns in temporal artery biopsies.

RESULTS

We identified 1555 hypomethylated CG sites (853 genes) in affected temporal artery tissue from patients with GCA compared with normal controls. Gene ontology enrichment analysis of hypomethylated genes revealed significant representation in T cell activation and differentiation pathways, including both TH1 and TH17 signatures. Our DNA methylation data suggest a role for increased activity of the calcineurin/nuclear factor of activated T cells (NFAT) signalling pathway in GCA, confirmed by immunohistochemistry showing increased expression and nuclear localisation of NFAT1. NFAT signalling downstream targets such as interleukin (IL)-21/IL-21R and CD40L were overexpressed in GCA-affected arteries. Further, proinflammatory genes including TNF, LTA, LTB, CCR7, RUNX3, CD6, CD40LG, IL2, IL6, NLRP1, IL1B, IL18, IL21, IL23R and IFNG were hypomethylated in the cellular milieu of GCA arteries.

CONCLUSIONS

We characterised the inflammatory response in GCA-affected arteries using 'epigenetic immunophenotyping' and identified molecules and pathways relevant to disease pathogenesis in GCA.

Effect of glucocorticoid treatment on computed tomography angiography detected large-vessel inflammation in giant-cell arteritis. A prospective, longitudinal study

Computed tomography angiography (CTA) detects signs of large-vessel vasculitis (LVV) in about 67.5% of patients with giant-cell arteritis (GCA) at the time of diagnosis and early aortic dilatation in 15%. The outcome of CTA-findings of LVV upon glucocorticoid treatment has not been prospectively evaluated. The aim of our study was to prospectively assess glucocorticoid-induced changes in CTA findings of LVV in patients with GCA. Forty biopsy-proven GCA patients evaluated by CTA at diagnosis were prospectively followed and scheduled a new CTA approximately after 1 year of treatment. Vessel wall thickening, diameter, and contrast enhancement of the aorta and its tributaries were evaluated. Results were compared to those obtained at the time of diagnosis. CTA was repeated to 35 patients after a median follow-up of 13.5 months (IQ25-75% 12.4-15.8). Arterial wall thickening was still present in 17 patients (68% of the patients who initially had LVV). The number of affected segments and wall thickness at various aortic segments significantly decreased and no patients developed new lesions, new aortic dilation or increase in previous dilation. Contrast enhancement disappeared in 15 (93.75%) of 16 patients in whom this finding could be assessed. Signs of LVV improve with treatment. While contrast enhancement resolves in the majority of patients, vessel wall thickening persists in two thirds. However, the number of affected aortic segments as well as aortic wall thickness significantly decreases. Longer follow-up is necessary to determine the clinical significance of persisting wall thickening and its relationship with relapses or subsequent development of aortic dilatation or large-vessel stenoses.

T cell-macrophage interactions and granuloma formation in vasculitis

Granuloma formation, bringing into close proximity highly activated macrophages and T cells, is a typical event in inflammatory blood vessel diseases, and is noted in the name of several of the vasculitides. It is not known whether specific properties of the microenvironment in the blood vessel wall or the immediate surroundings of blood vessels contribute to granuloma formation and, in some cases, generation of multinucleated giant cells. Granulomas provide a specialized niche to optimize macrophage-T cell interactions, strongly activating both cell types. This is mirrored by the intensity of the systemic inflammation encountered in patients with vasculitis, often presenting with malaise, weight loss, fever, and strongly upregulated acute phase responses. As a sophisticated and highly organized structure, granulomas can serve as an ideal site to induce differentiation and maturation of T cells. The granulomas possibly seed aberrant Th1 and Th17 cells into the circulation, which are known to be the main pathogenic cells in vasculitis. Through the induction of memory T cells, aberrant innate immune responses can imprint the host immune system for decades to come and promote chronicity of the disease process. Improved understanding of T cell-macrophage interactions will redefine pathogenic models in the vasculitides and provide new avenues for immunomodulatory therapy.

Biomarkers in vasculitis

PURPOSE OF REVIEW

Better biomarkers are needed for guiding management of patients with vasculitis. Large cohorts and technological advances had led to an increase in preclinical studies of potential biomarkers.

RECENT FINDINGS

The most interesting markers described recently include a gene expression signature in CD8+ T cells that predicts tendency to relapse or remain relapse-free in antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis, and a pair of urinary proteins that are elevated in Kawasaki disease but not other febrile illnesses. Both of these studies used 'omics' technologies to generate and then test hypotheses. More conventional hypothesis-based studies have indicated that the following circulating proteins have potential to improve upon clinically available tests: pentraxin-3 in giant cell arteritis and Takayasu's arteritis; von Willebrand factor antigen in childhood central nervous system vasculitis; eotaxin-3 and other markers related to eosinophils or Th2 immune responses in eosinophilic granulomatosis with polyangiitis (Churg-Strauss syndrome); and matrix metalloproteinase-3, tissue inhibitor of metalloproteinase-1, and CXCL13 in ANCA-associated vasculitis.

SUMMARY

New markers testable in blood and urine have the potential to assist with diagnosis, staging, assessment of current disease activity, and prognosis. However, the standards for clinical usefulness, in particular, the demonstration of either very high sensitivity or very high specificity have yet to be met for clinically relevant outcomes.

Relapses in patients with giant cell arteritis: prevalence, characteristics, and associated clinical findings in a longitudinally followed cohort of 106 patients

Giant cell arteritis (GCA) is a relapsing disease. However, the nature, chronology, therapeutic impact, and clinical consequences of relapses have been scarcely addressed. We conducted the present study to investigate the prevalence, timing, and characteristics of relapses in patients with GCA and to analyze whether a relapsing course is associated with disease-related complications, increased glucocorticoid (GC) doses, and GC-related adverse effects. The study cohort included 106 patients, longitudinally followed by the authors for 7.8 ± 3.3 years. Relapses were defined as reappearance of disease-related symptoms requiring treatment adjustment. Relapses were classified into 4 categories: polymyalgia rheumatica (PMR), cranial symptoms (including ischemic complications), systemic disease, or symptomatic large vessel involvement. Cumulated GC dose during the first year of treatment, time required to achieve a maintenance prednisone dose <10 mg/d (T10), <5 mg/d (T5), or complete prednisone discontinuation (T0), and GC-related side effects were recorded. Sixty-eight patients (64%) experienced at least 1 relapse, and 38 (36%) experienced 2 or more. First relapse consisted of PMR in 51%, cranial symptoms in 31%, and systemic complaints in 18%. Relapses appeared predominantly, but not exclusively, within the first 2 years of treatment, and only 1 patient developed visual loss. T10, T5, and T0 were significantly longer in patients with relapses than in patients without relapse (median, 40 vs 27 wk, p  < 0.0001; 163 vs 89.5 wk, p = 0.004; and 340 vs 190 wk, p = 0.001, respectively). Cumulated prednisone dose during the first year was significantly higher in relapsing patients (6.2 ± 1.7 g vs 5.4 ± 0.78 g, p = 0.015). Osteoporosis was more common in patients with relapses compared to those without (65% vs 32%, p = 0.001). In conclusion, the results of the present study provide evidence that a relapsing course is associated with higher and prolonged GC requirements and a higher frequency of osteoporosis in GCA.

Subclinical inflammation during third trimester of pregnancy was not associated with markers of the metabolic syndrome in young adult offspring

OBJECTIVE

Growing evidence indicates that the metabolic syndrome (MS) is rooted in adverse exposures during fetal life. The aim of this study was to assess the possible associations between biomarkers of inflammation during third trimester of pregnancy and markers of MS in adult offspring.

METHODS

High-sensitive C-reactive protein (CRP), tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β) and interleuki-6 (IL-6) were measured in serum samples obtained in gestational week 30. Offspring were clinically examined at age 20 years. Analyses based on 439 mother-offspring dyads were adjusted for maternal smoking during pregnancy, height, prepregnancy body mass index (BMI), education, and offspring's sex. Offspring MS markers included waist circumference, BMI, blood pressure, HOMA insulin resistance, and plasma levels of fasting glucose, triglycerides, cholesterol fractions, insulin, and leptin.

RESULTS

The median level was 2.8 (interquartile range = 3.3) µg/ml for CRP, for TNF-α: 5.7 (3.2) pg/ml, for IL-1β: 0.5 (0.4) pg/ml, and for IL-6: 1.1 (0.7) pg/ml. Concentrations were not significantly associated with MS markers in the offspring. The results remained essentially unchanged after correction for potential confounding.

CONCLUSION

Markers for subclinical inflammation in third trimester in healthy women were not associated with components of MS in their adult offspring.

Biologic Therapy for the Treatment of Giant Cell Arteritis

Giant cell arteritis (GCA), a vasculitis of the medium and large arteries, is traditionally managed with glucocorticoids. However, the side effects of chronic glucocorticoid use and the occurrence of refractory cases warrant the consideration of steroid-sparing agents, including biologic agents. Interleukin-6 (IL-6) inhibition shows the most promise as biologic therapy for refractory cases of GCA, but data to support the use of other existing biologic agents are currently lacking. A better understanding of the pathogenesis of GCA as well as clinical trials investigating both existing and emerging biologic agents is needed to expand therapeutic options for the treatment of GCA.

Anti-TNF-alpha therapy and systemic vasculitis

TNF-α is a pleiotropic cytokine, which plays a major role in the pathogenesis of numerous autoimmune and/or inflammatory systemic diseases. Systemic vasculitis constitutes a group of rare diseases, characterized by inflammation of the arterial or venous vessel wall, causing stenosis and thrombosis. Treatment of the different type of vasculitis mainly relies on steroids and immunosuppressive drugs. In case of refractory or relapsing diseases, however, a second line of treatment may be required. Anti-TNF-α drugs have been used in this setting during the last 15 years with inconsistent results. We reviewed herein the use of anti-TNF-α therapy in different kind of vasculitis and concluded that, except for Behcet's disease, this therapeutic option has not demonstrated significant improvement in the treatment of vasculitis.

Treatment with angiotensin II receptor blockers is associated with prolonged relapse-free survival, lower relapse rate, and corticosteroid-sparing effect in patients with giant cell arteritis

OBJECTIVE

To determine whether concomitant treatment with angiotensin-converting enzyme inhibitors (ACEI) or angiotensin receptor blockers (ARB) is associated with changes in the outcome of patients with giant cell arteritis (GCA).

METHODS

A study cohort of 106 patients with biopsy-proven GCA was longitudinally followed up for 7.8 ± 3.3 years. Patients were stratified according to their treatment with ACEI, ARB, or no ACEI/ARB. Time to first relapse, number of flares, time to achieve a stable prednisone dose <10mg/day and <5mg/day with no relapses, time required to completely discontinue prednisone, cumulative dose of prednisone received during the first year, and concentrations of acute-phase reactants at pre-defined time points (baseline, 6, 12, 18, and 24 months) were compared among the 3 groups. Cox proportional hazards models were performed to adjust for potential confounders.

RESULTS

Patients receiving ARB presented a significantly longer relapse-free survival than patients treated with ACEI or patients not receiving ACEI/ARB (p = 0.02). The adjusted hazard ratio for relapses in patients treated with ARB was 0.32 (95% CI: 0.12-0.81, p = 0.017). In addition, patients who received ARB achieved a prednisone maintenance dose <10mg/day faster than all other patients (p = 0.0002). No significant differences were observed among groups in acute-phase reactant levels during follow-up. However, patients not receiving ACEI/ARB had significantly higher C-reactive protein and haptoglobin concentrations than those receiving ACEI or ARB at various time points.

CONCLUSIONS

Addition of ARB to glucocorticoids is associated with lower relapse rate and more prolonged disease-free survival in patients with GCA.

Changes in biomarkers after therapeutic intervention in temporal arteries cultured in Matrigel: a new model for preclinical studies in giant-cell arteritis

BACKGROUND

Search for therapeutic targets in giant-cell arteritis (GCA) is hampered by the scarcity of functional systems. We developed a new model consisting of temporal artery culture in tri-dimensional matrix and assessed changes in biomarkers induced by glucocorticoid treatment.

METHODS

Temporal artery sections from 28 patients with GCA and 22 controls were cultured in Matrigel for 5 days in the presence or the absence of dexamethasone. Tissue mRNA concentrations of pro-inflammatory mediators and vascular remodelling molecules was assessed by real-time RT-PCR. Soluble molecules were measured in the supernatant fluid by immunoassay.

RESULTS

Histopathological features were exquisitely preserved in cultured arteries. mRNA concentrations of pro-inflammatory cytokines (particularly IL-1β and IFNγ), chemokines (CCL3/MIP-1α, CCL4/MIP-1β, CCL5/RANTES) and MMP-9 as well as IL-1β and MMP-9 protein concentrations in the supernatants were significantly higher in cultured arteries from patients compared with control arteries. The culture system itself upregulated expression of cytokines and vascular remodelling factors in control arteries. This minimised differences between patients and controls but underlines the relevance of changes observed. Dexamethasone downregulated pro-inflammatory mediator (IL-1β, IL-6, TNFα, IFNγ, MMP-9, TIMP-1, CCL3 and CXCL8) mRNAs but did not modify expression of vascular remodelling factors (platelet derived growth factor, MMP-2 and collagens I and III).

CONCLUSIONS

Differences in gene expression in temporal arteries from patients and controls are preserved during temporal artery culture in tri-dimensional matrix. Changes in biomarkers elicited by glucocorticoid treatment satisfactorily parallel results obtained in vivo. This may be a suitable model to explore pathogenetic pathways and to perform preclinical studies with new therapeutic agents.

Design of the tocilizumab in giant cell arteritis trial

Overview. The GiACTA trial is a multicenter, randomized, double-blind, and placebo-controlled study designed to test the ability of tocilizumab (TCZ), an interleukin (IL)-6 receptor antagonist, to maintain disease remission in patients with giant cell arteritis (GCA). Design. Approximately 100 centers will enroll 250 patients with active disease. The trial consists of a 52-week blinded treatment phase followed by 104 weeks of open-label extension. Patients will be randomized into one of four groups. Group A (TCZ 162 mg weekly plus a 6-month prednisone-taper); group B (TCZ 162 mg every other week plus a 6-month prednisone-taper); group C (placebo plus a 6-month prednisone-taper); and group D (placebo plus a 12-month prednisone taper). We hypothesize that patients assigned to TCZ in addition to a 6-month prednisone course are more likely to achieve the primary efficacy endpoint of sustained remission (SR) at 52 weeks compared with those assigned to a 6-month prednisone course alone, thus potentially minimizing the long-term adverse effects of corticosteroids. Conclusion. GiACTA will test the hypothesis that interference with IL-6 signaling exerts a beneficial effect on patients with GCA. The objective of this paper is to describe the design of the trial and address major issues related to its development.

Multimeric stability of human C-reactive protein in archived specimens

Background

C-reactive protein (CRP) is a marker of inflammation and a risk predictor of cardiovascular disease. Current CRP assays are focused on the quantification of the CRP levels as pentamers. However, CRP can be present as other multimeric forms. There will be a market need to measure the CRP multimeric structure in addition to the levels in human populations. To meet this need, we investigated whether the long-term archived samples could be used instead of freshly collected samples.

Methodology/Principal Findings

The specimens of serum, plasma and tissues were collected from transgenic rats expressing the human CRP. These samples were stored at 4°C, −20°C and −80°C for different periods. Non-denaturing Western blot analysis was used to observe the influence of storage conditions to multimeric structures of human CRP. Our results showed that there was no difference on multimeric structures of human CRP between samples stored at 4°C, −20°C and −80°C, between samples stored at −80°C for twenty-four hours and three months, and between plasma and serum.

Conclusions/Significance

This study implicated that archived samples stored at these conditions in those large longitudinal studies could be used for investigating the multimeric structures of CRP. Our report may speed up these researches and save labors and budget by enabling them to use currently available archived samples rather than freshly collected samples.

Increased IL-17A expression in temporal artery lesions is a predictor of sustained response to glucocorticoid treatment in patients with giant-cell arteritis

BACKGROUND

Interleukin 17A (IL-17A) exerts pivotal proinflammatory functions in chronic inflammatory and autoimmune diseases.

OBJECTIVE

To investigate IL-17A expression in temporal artery lesions from patients with giant-cell arteritis (GCA), and its relationship with disease outcome.

METHODS

Fifty-seven patients with biopsy-proven GCA were prospectively evaluated, treated and followed for 4.5 years (52-464 weeks). Relapses, time (weeks) required to achieve a maintenance prednisone dose <10 mg/day, and time (weeks) to complete prednisone withdrawal were prospectively recorded. IL-17A mRNA was measured by real-time quantitative RT-PCR in temporal arteries from all patients and 19 controls. IL-17 protein expression was assessed by immunohistochemistry/immunofluorescence.

RESULTS

IL-17A expression was significantly increased in temporal artery samples from GCA patients compared with controls (6.22±8.61 vs 2.50±3.9 relative units, p=0.016). Surprisingly, patients with strong IL-17A expression tended to experience less relapses, and required significantly shorter treatment periods (median 25 vs 44 weeks to achieve <10 mg prednisone/day, p=0.0079). There was no correlation between IL-17A and RORc or RORα expression suggesting that these transcription factors may not exclusively reflect Th17 differentiation, and that cells other than Th17 cells might contribute to IL-17 expression in active patients. Accordingly, FoxP3(+)IL-17A(+) cells were identified in lesions by confocal microscopy and were dramatically reduced in specimens from treated patients.

CONCLUSIONS

IL-17A expression is increased in GCA lesions, and is a predictor of response to glucocorticoid treatment. The contribution of FoxP3+ cells to IL-17A production in untreated patients suggests that induced-Tregs may facilitate disease remission when proinflammatory cytokine production is downregulated by glucocorticosteroids.

Clinical features of polymyalgia rheumatica and giant cell arteritis

Polymyalgia rheumatica (PMR) and giant cell arteritis (GCA) are inflammatory diseases that typically affect white individuals >50 years. Women are affected ∼2-3 times more often than men. PMR and GCA occur together more frequently than expected by chance. The main symptoms of PMR are pain and stiffness in the shoulders, and often in the neck and pelvic girdle. Imaging studies reveal inflammation of joints and bursae of the affected areas. GCA is a large-vessel and medium-vessel arteritis predominantly involving the branches of the aortic arch. The typical clinical manifestations of GCA are new headache, jaw claudication and visual loss. PMR and GCA usually remit within 6 months to 2 years from disease onset. Some patients, however, have a relapsing course and might require long-standing treatment. Diagnosis of PMR and GCA is based on clinical features and elevated levels of inflammatory markers. Temporal artery biopsy remains the gold standard to support the diagnosis of GCA; imaging studies are useful to delineate large-vessel involvement in GCA. Glucocorticoids remain the cornerstone of treatment of both PMR and GCA, but patients with GCA require higher doses. Synthetic immunosuppressive drugs also have a role in disease management, whereas the role of biologic agents is currently unclear.