Project description:Juvenile idiopathic arthritis (JIA) is the most common rheumatic disease of childhood, with JIA-associated uveitis its most common extra-articular manifestation. JIA-associated uveitis is a potentially sight-threatening condition and thus carries a considerable risk of morbidity. The aetiology of the condition is autoimmune in nature with the predominant involvement of CD4(+) T cells. However, the underlying pathogenic mechanisms remain unclear, particularly regarding interplay between genetic and environmental factors. JIA-associated uveitis comes in several forms, but the most common presentation is of the chronic anterior uveitis type. This condition is usually asymptomatic and thus screening for JIA-associated uveitis in at-risk patients is paramount. Early detection and treatment aims to stop inflammation and prevent the development of complications leading to visual loss, which can occur due to both active disease and burden of disease treatment. Visually disabling complications of JIA-associated uveitis include cataracts, glaucoma, band keratopathy and macular oedema. There is a growing body of evidence for the early introduction of systemic immunosuppressive therapies in order to reduce topical and systemic glucocorticoid use. This includes more traditional treatments, such as methotrexate, as well as newer biological therapies. This review highlights the epidemiology of JIA-associated uveitis, the underlying pathogenesis and how affected patients may present. The current guidelines and criteria for screening, diagnosis and monitoring are discussed along with approaches to management.
Project description:Deep whole genome sequencing (WGS) allows for the comprehensive study of genetic landscapes at finer resolution than array based methods. We conducted deep WGS on children with the polyarticular form of juvenile idiopathic arthritis (JIA), using 2 independent cohorts to ascertain the sequencing fidelity. Genome wide SNP density analysis identified 18 SNP hotspots with comparison to the 1000 Genome Projects (1KGP) data. A subset of the genes adjacent to SNP hotspots showed statistically significant enrichment in immunological processes. Genes adjacent to indel hotspots were functionally related to G-protein coupled signaling pathways. Further analyses elucidated significantly more JIA SNPs with regulatory potential compared to 1KGP data. Furthermore, SNPs located within linkage disequibilium (LD) blocks containing previously identified JIA-associated SNPs demonstrated higher regulation potential compared to SNPs outside LD blocks. We also demonstrated enrichment of novel JIA variants in histone modification peaks and DNase hypersensitivity sites in B cells. This study greatly expands the number of genetic variants that may contribute to JIA and give us some clues into what may trigger this disease. To date, this study is the first deep WGS effort on children with JIA and provides useful genetic resources for research communities particularly in understanding JIA etiology.
Project description:To describe recent evidence from the literature pertaining to juvenile idiopathic arthritis (JIA)-associated uveitis.Uveitis is most common in extended oligoarticular JIA. A significant number of patients already have ocular complications at time of diagnosis of uveitis. Risk factors for complications include either abnormally high or low intraocular pressure, posterior synechiae, male sex, temporal proximity to diagnosis of arthritis and topical corticosteroid use. Use of immunosuppressive agents significantly reduces ocular complications. Aggressive perioperative control of intraocular inflammation is necessary for successful cataract surgery with lens implantation. Controlled clinical trials are under way to assess the efficacy of biologic agents in JIA-associated uveitis. Long-term safety, however, is still unknown.JIA-associated uveitis carries significant ocular morbidity that lasts well into adulthood. Treatment with immunosuppressive agents can reduce the risk of ocular complications. Biologic agents hold promise in the treatment of JIA-associated uveitis, but require long-term data to assess their safety.
Project description:Juvenile idiopathic arthritis (JIA) is the most common childhood rheumatic disease. The development of associated uveitis represents a significant risk for serious complications, including permanent loss of vision. Initiation of early treatment is important for controlling JIA-uveitis, but the disease can appear asymptomatically, making frequent screening procedures necessary for patients at risk. As our understanding of pathogenic drivers is currently incomplete, it is difficult to assess which JIA patients are at risk of developing uveitis. Identification of specific risk factors for JIA-associated uveitis is an important field of research, and in this review, we highlight the genomic, transcriptomic, and proteomic factors identified as potential uveitis risk factors in JIA, and discuss therapeutic strategies.
Project description:BackgroundHaptoglobin (Hp), a liver derived acute phase inflammatory protein (APP), has scarcely been studied in juvenile idiopathic arthritis (JIA). Hp can occur in blood as two isoforms (Hp1 and Hp2) in precursor and mature forms. Routine clinical chemistry immunoturbidimetry does not discern these forms. It is unknown how different forms relate to disease activity in JIA. Our aims were to determine allele frequency and plasma concentrations of different Hp forms at higher versus lower JIA disease activity and compare to other APPs.MethodsPlasma from JIA (n = 77) and healthy (n = 42) children were analyzed for apparent Hp allelic frequency and densitometric concentrations of alpha forms by Western blot (WB). Polymerase chain reaction (PCR) (buffy coat) was performed in a subset to estimate conformity with genetics. At higher versus lower juvenile arthritis disease activity score (JADAS27) (which includes erythrocyte sedimentation rate (ESR)), total mature Hp concentration from WB was compared and correlated against immunoturbidimetry and total protein, albumin, serum amyloid A (SAA) and C-reactive protein (CRP).ResultsAt 300-fold dilution needed to study mature forms in Western blot, precursors were undetectable. Hp2 contributed most signal in most samples. Hp allele frequency was similar in JIA and controls. Both mature forms, taken separately or by sum, declined following treatment, but remained above concentrations of healthy controls, even in a remission subset that achieved JADAS27 < 1. Densitometry correlated with immunoturbidimetry. Hp concentrations correlated with JADAS27, albumin (negatively), CRP and SAA with immunoturbidimetric method correlating strongest to JADAS27 (Spearman R ~ 0.6, p < 0.0001).ConclusionHp allele frequency in JIA is similar to the general population, indicating that children with JIA should have the same possibility as in healthy children to produce preHp2 (zonulin), thought to increase intestinal permeability. Circulating Hp concentrations largely parallel other APPs and ESR; none of these measures correlate very strongly to JADAS27 score but Hp can be measured from capillary sampling which is impossible with ESR.
Project description:Systemic-onset juvenile idiopathic arthritis (soJIA) is a rheumatic disease in childhood characterized by systemic symptoms and a relatively poor prognosis. The peripheral leukocytes are thought to play the pathological role of soJIA although the exact cause is still obscure. In this study, we aimed to clarify the cellular functional abnormality in those cells. Here, we analyzed the gene expression profile in peripheral leukocytes from 51 patients with soJIA, 6 patients with poly-articular type JIA (polyJIA) and 8 healthy children utilizing DNA microarrays. A total of 3,491 genes, including genes related to immune reponse and metabolism, were differentially expressed in patients with soJIA compared to healthy individuals. The result provides insight into the pathogenesis of soJIA. Keywords: disease state analysis
Project description:Identify biomarkers to predict response to therapy in polyarticular juvenile idiopathic arthritis (JIA) using gene expression microarrays.
Project description:Identify biomarkers to predict response to therapy in polyarticular juvenile idiopathic arthritis (JIA) using gene expression microarrays. 42 samples from 13 controls, 14 active patients, 9 patients in clinical remission with medication (CRM), and 6 patients in clinical remission without medication (CR). All patients had polyarticular JIA.
Project description:Systemic-onset juvenile idiopathic arthritis (soJIA) is a rheumatic disease in childhood characterized by systemic symptoms and a relatively poor prognosis. The peripheral leukocytes are thought to play the pathological role of soJIA although the exact cause is still obscure. In this study, we aimed to clarify the cellular functional abnormality in those cells. Here, we analyzed the gene expression profile in peripheral leukocytes from 51 patients with soJIA, 6 patients with poly-articular type JIA (polyJIA) and 8 healthy children utilizing DNA microarrays. A total of 3,491 genes, including genes related to immune reponse and metabolism, were differentially expressed in patients with soJIA compared to healthy individuals. The result provides insight into the pathogenesis of soJIA. Keywords: disease state analysis Total RNA was extracted from peripheral leukocytes from 51 soJIA patients, 6 poly-articular type JIA patients, and 8 healthy children. The gene expression profile was analyzed with DNA microarrays.
Project description:OBJECTIVES:Juvenile idiopathic arthritis (JIA) is a heterogeneous group of conditions unified by the presence of chronic childhood arthritis without an identifiable cause. Systemic JIA (sJIA) is a rare form of JIA characterised by systemic inflammation. sJIA is distinguished from other forms of JIA by unique clinical features and treatment responses that are similar to autoinflammatory diseases. However, approximately half of children with sJIA develop destructive, long-standing arthritis that appears similar to other forms of JIA. Using genomic approaches, we sought to gain novel insights into the pathophysiology of sJIA and its relationship with other forms of JIA. METHODS:We performed a genome-wide association study of 770 children with sJIA collected in nine countries by the International Childhood Arthritis Genetics Consortium. Single nucleotide polymorphisms were tested for association with sJIA. Weighted genetic risk scores were used to compare the genetic architecture of sJIA with other JIA subtypes. RESULTS:The major histocompatibility complex locus and a locus on chromosome 1 each showed association with sJIA exceeding the threshold for genome-wide significance, while 23 other novel loci were suggestive of association with sJIA. Using a combination of genetic and statistical approaches, we found no evidence of shared genetic architecture between sJIA and other common JIA subtypes. CONCLUSIONS:The lack of shared genetic risk factors between sJIA and other JIA subtypes supports the hypothesis that sJIA is a unique disease process and argues for a different classification framework. Research to improve sJIA therapy should target its unique genetics and specific pathophysiological pathways.