Kenneth J. Warrington

CD4+,CD28- T cells in rheumatoid arthritis patients combine features of the innate and adaptive immune systems.

OBJECTIVE To determine whether CD4+,CD28- T cells, which are expanded in patients with rheumatoid arthritis (RA), express receptors that typically regulate the function of natural killer (NK) cells. METHODS Expression of the NK cell surface molecules CD158, p70, CD94, CD161, and CD8alpha on T cell subsets was determined by multicolor flow cytometric analysis of peripheral blood mononuclear cells from 36 RA patients. Expression of CD161 on tissue-infiltrating CD4 T cells was determined by 2-color immunohistochemistry analysis of synovial tissue samples. RESULTS Killer cell-inhibitory receptors (KIR) and killer cell-activating receptors (KAR) were exclusively expressed on CD4+,CD28- T cells, with the CD158b molecule being the most frequently detected isoform. A coordinated mechanism inducing KIR/KAR expression was suggested by similarities in the expression of CD158b on CD4 and CD8 T cells. CD4+,CD28- T cells were also positive for CD8-alphaalpha homodimers, another characteristic shared with NK cells. Of the C-type lectin NK cell receptors (NK receptors), CD94 was consistently absent, but CD161 was found on a CD4 T cell population that is significantly expanded in RA patients (P = 0.01). Involvement in disease of NK receptor-expressing CD4 T cells was suggested by the presence of CD4+,CD161+ T cells in follicular microstructures typical of rheumatoid synovitis. CONCLUSION Patients with RA have an expanded and unusual subset of CD4 T cells that infiltrates the tissue lesions and is characterized by a deficiency of CD28, the expression of CD8-alphaalpha homodimers, and the expression of several types of HLA class I-recognizing NK receptors. CD4 T cells bearing NK receptors can bridge functions of the innate and adaptive immune systems, such as responsiveness to specific antigen, rapid release of interferon-gamma, cytotoxicity, independence from classic costimulatory pathways, and integration of multiple activating and inhibitory signals to control effector functions.

The lifetime risk of adult‐onset rheumatoid arthritis and other inflammatory autoimmune rheumatic diseases

OBJECTIVE Understanding of the personal risks for rheumatoid arthritis (RA) and other rheumatic diseases remains poor, despite advances in knowledge with regard to their pathogenesis, therapeutics, and clinical impact, in part because the personal lifetime risk of developing these diseases is unknown. This study was undertaken to estimate the lifetime risk of RA, as well as other inflammatory autoimmune rheumatic diseases, including systemic lupus erythematosus, psoriatic arthritis, polymyalgia rheumatica (PMR), giant cell arteritis, ankylosing spondylitis, and Sjögrens syndrome, and to provide an overall estimate of the risk of developing inflammatory autoimmune rheumatic disease over a lifetime. METHODS Using the incidence rates obtained from our population-based studies of rheumatic diseases among residents of Olmsted County, Minnesota, and mortality rates from life tables for the general population, we estimated the sex-specific lifetime risk of rheumatic disease. RESULTS The lifetime risk of RA developing in US adults was 3.6% for women and 1.7% for men, and the lifetime risk of rheumatoid factor-positive RA was 2.4% for women and 1.1% for men. The second most common inflammatory autoimmune rheumatic disease was PMR, with a lifetime risk of 2.4% for women and 1.7% for men. The overall lifetime risk of inflammatory autoimmune rheumatic disease was 8.4% for women and 5.1% for men. CONCLUSION One in 12 women and 1 in 20 men will develop an inflammatory autoimmune rheumatic disease during their lifetime. These results can serve as useful guides in counseling patients regarding their lifetime risk of these conditions and have important implications regarding disease awareness campaigns.

Rheumatoid arthritis is an independent risk factor for multi-vessel coronary artery disease: a case control study

The risk for cardiovascular (CV) disease is increased in rheumatoid arthritis (RA) but data on the burden of coronary atherosclerosis in patients with RA are lacking. We conducted a retrospective case-control study of Olmsted County (MN, USA) residents with RA and new-onset coronary artery disease (CAD) (n = 75) in comparison with age-and sex-matched controls with newly diagnosed CAD (n = 128). Angiographic scores of the first coronary angiogram and data on CV risk factors and CV events on follow-up were obtained by chart abstraction. Patients with RA were more likely to have multi-vessel coronary involvement at first coronary angiogram compared with controls (P = 0.002). Risk factors for CAD including diabetes, hypertension, hyperlipidemia, and smoking history were not significantly different in the two cohorts. RA remained a significant risk factor for multi-vessel disease after adjustment for age, sex and history of hyperlipidemia. The overall rate of CV events was similar in RA patients and controls; however, there was a trend for increased CV death in patients with RA. In a nested cohort of patients with RA and CAD (n = 27), we measured levels of pro-inflammatory CD4+CD28null T cells by flow cytometry. These T cells have been previously implicated in the pathogenesis of CAD and RA. Indeed, CD4+CD28null T cells were significantly higher in patients with CAD and co-existent RA than in controls with stable angina (P = 0.001) and reached levels found in patients with acute coronary syndromes. Patients with RA are at increased risk for multi-vessel CAD, although the risk of CV events was not increased in our study population. Expansion of CD4+CD28null T cells in these patients may contribute to the progression of atherosclerosis.

Distribution of arterial lesions in Takayasu's arteritis and giant cell arteritis

Objectives To compare patterns of arteriographic lesions of the aorta and primary branches in patients with Takayasus arteritis (TAK) and giant cell arteritis (GCA). Methods Patients were selected from two North American cohorts of TAK and GCA. The frequency of arteriographic lesions was calculated for 15 large arteries. Cluster analysis was used to derive patterns of arterial disease in TAK versus GCA and in patients categorised by age at disease onset. Using latent class analysis, computer derived classification models based upon patterns of arterial disease were compared with traditional classification. Results Arteriographic lesions were identified in 145 patients with TAK and 62 patients with GCA. Cluster analysis demonstrated that arterial involvement was contiguous in the aorta and usually symmetric in paired branch vessels for TAK and GCA. There was significantly more left carotid (p=0.03) and mesenteric (p=0.02) artery disease in TAK and more left and right axillary (p<0.01) artery disease in GCA. Subclavian disease clustered asymmetrically in TAK and in patients ≤55 years at disease onset and clustered symmetrically in GCA and patients >55 years at disease onset. Computer derived classification models distinguished TAK from GCA in two subgroups, defining 26% and 18% of the study sample; however, 56% of patients were classified into a subgroup that did not strongly differentiate between TAK and GCA. Conclusions Strong similarities and subtle differences in the distribution of arterial disease were observed between TAK and GCA. These findings suggest that TAK and GCA may exist on a spectrum within the same disease.

Aldosteronism and Peripheral Blood Mononuclear Cell Activation: A Neuroendocrine-Immune Interface

Abstract— Aldosteronism eventuates in a proinflammatory/fibrogenic vascular phenotype of the heart and systemic organs. It remains uncertain whether peripheral blood mononuclear cells (PBMCs) are activated before tissue invasion by monocytes/macrophages and lymphocytes, as is the case for responsible pathogenic mechanisms. Uninephrectomized rats treated for 4 weeks with dietary 1% NaCl and aldosterone (ALDOST, 0.75 &mgr;g/h) with or without spironolactone (Spi, 100 mg/kg per daily gavage) were compared with unoperated/untreated and uninephrectomized/salt-treated controls. Before intramural coronary vascular lesions appeared at week 4 of ALDOST, we found (1) a reduction of PBMC cytosolic free [Mg2+]i, together with intracellular Mg2+ and Ca2+ loading, whereas plasma and cardiac tissue Mg2+ were no different from controls; (2) increased H2O2 production by monocytes and lymphocytes together with upregulated PBMC gene expression of oxidative stress–inducible tyrosine phosphatase and Mn2+-superoxide dismutase and the presence of 3-nitrotyrosine in CD4+ and ED-1–positive inflammatory cells that had invaded intramural coronary arteries; (3) B-cell activation, including transcription of immunoglobulins, intracellular adhesion molecule-1, and CC and CXC chemokines and their receptors; (4) expansion of B lymphocyte subset and myosin heavy chain class II–expressing lymphocytes; and (5) autoreactivity with gene expression for antibodies to acetylcholine receptors and a downregulation of RT-6.2, which is in keeping with cell activation and associated with autoimmunity. Spi cotreatment attenuated the rise in intracellular Ca2+, the appearance of oxidative/nitrosative stress in PBMCs and invading inflammatory cells, and alterations in PBMC transcriptome. Thus, aldosteronism is associated with an activation of circulating immune cells induced by iterations in PBMC divalent cations and transduced by oxidative/nitrosative stress. ALDO receptor antagonism modulates this neuroendocrine-immune interface. The full text of this article is available online at http://www.circresaha.org.

Large-vessel involvement in giant cell arteritis: a population-based cohort study of the incidence-trends and prognosis

Objectives To evaluate incidence-trends and timing of large-vessel (LV) manifestations in patients with giant cell arteritis (GCA), and to examine the influence of LV manifestations on survival. Methods A population-based incident cohort of patients diagnosed with GCA between 1950 and 2004 was used. LV involvement was defined as large-artery stenosis or aortic aneurysm/dissection that developed in the 1 year before GCA diagnosis or at any time thereafter. Patients were followed up until death or 31 December 2009. Results The study included 204 patients, 80% women, mean age at diagnosis of GCA 76.0 years (±8.2 years). Median length of follow-up was 8.8 years. The cumulative incidence of any LV manifestation at 10 years was 24.9% for patients diagnosed with GCA between 1980 and 2004 compared with 8.3% for patients diagnosed with GCA between 1950 and 1979. The incidence of any LV event was high within the first year of GCA diagnosis. The incidence of aortic aneurysm/dissection increased 5 years after GCA diagnosis. Compared with the general population, survival was decreased in patients with an aortic aneurysm/dissection (standardized mortality ratio (SMR) 2.63; 95% CI 1.78 to 3.73) but not in patients with large-artery stenosis (SMR 1.44; 95% CI 0.87 to 2.25). Patients with GCA and aortic manifestations had a higher than expected number of deaths from cardiovascular and pulmonary causes than the general population. Among patients with GCA, aortic manifestations were associated with increased mortality (HR=3.4; 95% CI 2.2 to 5.4). Conclusions Vigilance and screening for aortic aneurysms should be considered in all patients 5 years after the incidence of GCA. Aortic aneurysm/dissection is associated with increased mortality in GCA.

Utility of Erythrocyte Sedimentation Rate and C-Reactive Protein for the Diagnosis of Giant Cell Arteritis

OBJECTIVES To evaluate the utility of erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) for the diagnosis of giant cell arteritis (GCA) and to determine the frequency of normal ESR and CRP at diagnosis of GCA. METHODS All patients undergoing temporal artery biopsy (TAB) between 2000 and 2008 were identified. Only subjects with both ESR and CRP at the time of TAB were included. The medical records of all patients were reviewed. RESULTS We included 764 patients (65% women), mean age 72.7 (±9.27) years, who underwent TAB. Biopsy was consistent with GCA in 177 patients (23%). Elevated CRP and elevated ESR provided a sensitivity of 86.9% and 84.1%, respectively, for a positive TAB. The odds ratio of a concordantly elevated ESR and CRP for positive TAB was 3.06 (95% CI 2.03, 4.62), whereas the odds ratio for concordantly normal ESR and CRP was 0.49 (95% CI 0.29, 0.83). Seven patients (4%) with a positive TAB for GCA had a normal ESR and CRP at diagnosis. Compared with GCA patients with elevated markers of inflammation, a greater proportion of these patients had polymyalgia rheumatica symptoms (P = 0.008), whereas constitutional symptoms, anemia and thrombocytosis, were observed less often (P < 0.05). CONCLUSIONS CRP is a more sensitive marker than ESR for a positive TAB that is diagnostic of GCA. There may be clinical utility in obtaining both tests in the evaluation of patients with suspected GCA. A small proportion of patients with GCA may have normal inflammatory markers at diagnosis.

The shrinking lungs syndrome in systemic lupus erythematosus

A comprehensive review of the literature on shrinking lungs syndrome (SLS) in systemic lupus erythematosus involved a MEDLINE search (1965-1997) of case reports and clinical series of patients with the diagnosis of SLS. A total of 49 well-documented cases of SLS were reviewed. Shrinking lungs syndrome is characterized by unexplained dyspnea, a restrictive pattern on pulmonary function test results, and an elevated hemidiaphragm. The cause of SLS remains controversial, with several authors attributing the disorder to diaphragmatic weakness and others suggesting that chest wall restriction accounts for the clinical syndrome. No definitive therapy exists. Corticosteroids have been reported to lessen symptoms and improve pulmonary function in some patients with SLS, but other methods of treatment have occasionally been found to be helpful. Clinical presentation, method of diagnosis, pathogenesis, and treatment modalities are summarized in this review. An uncommon complication of systemic lupus erythematosus, SLS causes significant morbidity and, occasionally, mortality.

Dual-energy CT for the diagnosis of gout: an accuracy and diagnostic yield study

Objectives To assess the accuracy of dual-energy CT (DECT) for diagnosing gout, and to explore whether it can have any impact on clinical decision making beyond the established diagnostic approach using polarising microscopy of synovial fluid (diagnostic yield). Methods Diagnostic single-centre study of 40 patients with active gout, and 41 individuals with other types of joint disease. Sensitivity and specificity of DECT for diagnosing gout was calculated against a combined reference standard (polarising and electron microscopy of synovial fluid). To explore the diagnostic yield of DECT scanning, a third cohort was assembled consisting of patients with inflammatory arthritis and risk factors for gout who had negative synovial fluid polarising microscopy results. Among these patients, the proportion of subjects with DECT findings indicating a diagnosis of gout was assessed. Results The sensitivity and specificity of DECT for diagnosing gout was 0.90 (95% CI 0.76 to 0.97) and 0.83 (95% CI 0.68 to 0.93), respectively. All false negative patients were observed among patients with acute, recent-onset gout. All false positive patients had advanced knee osteoarthritis. DECT in the diagnostic yield cohort revealed evidence of uric acid deposition in 14 out of 30 patients (46.7%). Conclusions DECT provides good diagnostic accuracy for detection of monosodium urate (MSU) deposits in patients with gout. However, sensitivity is lower in patients with recent-onset disease. DECT has a significant impact on clinical decision making when gout is suspected, but polarising microscopy of synovial fluid fails to demonstrate the presence of MSU crystals.

Identification of multiple genetic susceptibility loci in Takayasu arteritis

Takayasu arteritis is a rare inflammatory disease of large arteries. The etiology of Takayasu arteritis remains poorly understood, but genetic contribution to the disease pathogenesis is supported by the genetic association with HLA-B*52. We genotyped ~200,000 genetic variants in two ethnically divergent Takayasu arteritis cohorts from Turkey and North America by using a custom-designed genotyping platform (Immunochip). Additional genetic variants and the classical HLA alleles were imputed and analyzed. We identified and confirmed two independent susceptibility loci within the HLA region (r(2) < 0.2): HLA-B/MICA (rs12524487, OR = 3.29, p = 5.57 × 10(-16)) and HLA-DQB1/HLA-DRB1 (rs113452171, OR = 2.34, p = 3.74 × 10(-9); and rs189754752, OR = 2.47, p = 4.22 × 10(-9)). In addition, we identified and confirmed a genetic association between Takayasu arteritis and the FCGR2A/FCGR3A locus on chromosome 1 (rs10919543, OR = 1.81, p = 5.89 × 10(-12)). The risk allele in this locus results in increased mRNA expression of FCGR2A. We also established the genetic association between IL12B and Takayasu arteritis (rs56167332, OR = 1.54, p = 2.18 × 10(-8)).