John Varga

2013 Classification Criteria for Systemic Sclerosis: An American College of Rheumatology/European League Against Rheumatism Collaborative Initiative

OBJECTIVE The 1980 American College of Rheumatology (ACR) classification criteria for systemic sclerosis (SSc) lack sensitivity for early SSc and limited cutaneous SSc. The present work, by a joint committee of the ACR and the European League Against Rheumatism (EULAR), was undertaken for the purpose of developing new classification criteria for SSc. METHODS Using consensus methods, 23 candidate items were arranged in a multicriteria additive point system with a threshold to classify cases as SSc. The classification system was reduced by clustering items and simplifying weights. The system was tested by 1) determining specificity and sensitivity in SSc cases and controls with scleroderma-like disorders, and 2) validating against the combined view of a group of experts on a set of cases with or without SSc. RESULTS It was determined that skin thickening of the fingers extending proximal to the metacarpophalangeal joints is sufficient for the patient to be classified as having SSc; if that is not present, 7 additive items apply, with varying weights for each: skin thickening of the fingers, fingertip lesions, telangiectasia, abnormal nailfold capillaries, interstitial lung disease or pulmonary arterial hypertension, Raynauds phenomenon, and SSc-related autoantibodies. Sensitivity and specificity in the validation sample were, respectively, 0.91 and 0.92 for the new classification criteria and 0.75 and 0.72 for the 1980 ACR classification criteria. All selected cases were classified in accordance with consensus-based expert opinion. All cases classified as SSc according to the 1980 ACR criteria were classified as SSc with the new criteria, and several additional cases were now considered to be SSc. CONCLUSION The ACR/EULAR classification criteria for SSc performed better than the 1980 ACR criteria for SSc and should allow for more patients to be classified correctly as having the disease.

Systemic sclerosis: a prototypic multisystem fibrotic disorder

A unique feature of systemic sclerosis (SSc) that distinguishes it from other fibrotic disorders is that autoimmunity and vasculopathy characteristically precede fibrosis. Moreover, fibrosis in SSc is not restricted to a single organ, but rather affects many organs and accounts for much of the morbidity and mortality associated with this disease. Although immunomodulatory drugs have been used extensively in the treatment of SSc, no therapy to date has been able to reverse or slow the progression of tissue fibrosis or substantially modify the natural progression of the disease. In this Review, we highlight recent studies that shed light on the cellular and molecular mechanisms underlying the fibrotic process in SSc and that identify cellular processes and intra- and extracellular proteins as potential novel targets for therapy in this prototypic multisystemic fibrotic disease.

Recent developments in myofibroblast biology: paradigms for connective tissue remodeling.

The discovery of the myofibroblast has opened new perspectives for the comprehension of the biological mechanisms involved in wound healing and fibrotic diseases. In recent years, many advances have been made in understanding important aspects of myofibroblast basic biological characteristics. This review summarizes such advances in several fields, such as the following: i) force production by the myofibroblast and mechanisms of connective tissue remodeling; ii) factors controlling the expression of α-smooth muscle actin, the most used marker of myofibroblastic phenotype and, more important, involved in force generation by the myofibroblast; and iii) factors affecting genesis of the myofibroblast and its differentiation from precursor cells, in particular epigenetic factors, such as DNA methylation, microRNAs, and histone modification. We also review the origin and the specific features of the myofibroblast in diverse fibrotic lesions, such as systemic sclerosis; kidney, liver, and lung fibrosis; and the stromal reaction to certain epithelial tumors. Finally, we summarize the emerging strategies for influencing myofibroblast behavior in vitro and in vivo, with the ultimate goal of an effective therapeutic approach for myofibroblast-dependent diseases.

2013 classification criteria for systemic sclerosis: an American college of rheumatology/European league against rheumatism collaborative initiative

Objective The 1980 American College of Rheumatology (ACR) classification criteria for systemic sclerosis (SSc) lack sensitivity for early SSc and limited cutaneous SSc. The present work, by a joint committee of the ACR and the European League Against Rheumatism (EULAR), was undertaken for the purpose of developing new classification criteria for SSc. Methods Using consensus methods, 23 candidate items were arranged in a multicriteria additive point system with a threshold to classify cases as SSc. The classification system was reduced by clustering items and simplifying weights. The system was tested by (1) determining specificity and sensitivity in SSc cases and controls with scleroderma-like disorders, and (2) validating against the combined view of a group of experts on a set of cases with or without SSc. Results It was determined that skin thickening of the fingers extending proximal to the metacarpophalangeal joints is sufficient for the patient to be classified as having SSc; if that is not present, seven additive items apply, with varying weights for each: skin thickening of the fingers, fingertip lesions, telangiectasia, abnormal nailfold capillaries, interstitial lung disease or pulmonary arterial hypertension, Raynauds phenomenon, and SSc-related autoantibodies. Sensitivity and specificity in the validation sample were, respectively, 0.91 and 0.92 for the new classification criteria and 0.75 and 0.72 for the 1980 ACR classification criteria. All selected cases were classified in accordance with consensus-based expert opinion. All cases classified as SSc according to the 1980 ACR criteria were classified as SSc with the new criteria, and several additional cases were now considered to be SSc. Conclusions The ACR/EULAR classification criteria for SSc performed better than the 1980 ACR criteria for SSc and should allow for more patients to be classified correctly as having the disease.

High-dose versus low-dose D-penicillamine in early diffuse systemic sclerosis: Analysis of a two-year, double-blind, randomized, controlled clinical trial

OBJECTIVE To test the hypothesis that systemic sclerosis (SSc) patients taking high-dose D-penicillamine (D-Pen) would have greater softening of skin, lower frequency of renal crisis, and better survival than patients taking low-dose D-Pen. METHODS Seventeen centers enrolled 134 SSc patients with early (< or =18 months) diffuse cutaneous scleroderma into a 2-year, double-blind, randomized comparison of high-dose D-Pen (750-1,000 mg/day) versus low-dose D-Pen (125 mg every other day). All 134 patients were followed up for a mean+/-SD of 4.0+/-1.1 years to assess the frequencies of new-onset scleroderma renal crisis (SRC) and mortality. RESULTS Sixty-eight patients completed 24 months of drug treatment. The course of the modified Rodnan skin thickness score in the 32 high-dose and the 36 low-dose D-Pen completers was not different at 24 months: the skin score dropped 4.8+/-10.3 (mean+/-SD) units in the high-dose group and 6.9+/-8.4 units in the low-dose group (P = 0.384 by t-test; favoring low-dose D-Pen) from 20.4+/-10.3 in the high-dose and 19.9+/-6.6 in the low-dose D-Pen group at study entry. The incidences of SRC and mortality were not different (P > 0.38 by Cox proportional hazards and by chi-square test) in the 66 high-dose patients (8 developed SRC and 8 died) compared with the 68 low-dose patients (10 developed SRC and 12 died). Of the 20 adverse event-related withdrawals, 80% occurred in the high-dose D-Pen group. CONCLUSION The course of the skin score and the frequencies of SRC and mortality in the high-dose D-Pen group were not different from those in the low-dose D-Pen group. Eighty percent of the adverse event-related withdrawals occurred in the high-dose D-Pen patients. Although this study cannot answer the question of whether low-dose D-Pen is effective, it does suggest that there is no advantage to using D-Pen in doses higher than 125 every other day.

Genome-wide association study of systemic sclerosis identifies CD247 as a new susceptibility locus

Systemic sclerosis (SSc) is an autoimmune disease characterized by fibrosis of the skin and internal organs that leads to profound disability and premature death. To identify new SSc susceptibility loci, we conducted the first genome-wide association study in a population of European ancestry including a total of 2,296 individuals with SSc and 5,171 controls. Analysis of 279,621 autosomal SNPs followed by replication testing in an independent case-control set of European ancestry (2,753 individuals with SSc (cases) and 4,569 controls) identified a new susceptibility locus for systemic sclerosis at CD247 (1q22–23, rs2056626, P = 2.09 × 10−7 in the discovery samples, P = 3.39 × 10−9 in the combined analysis). Additionally, we confirm and firmly establish the role of the MHC (P = 2.31 × 10−18), IRF5 (P = 1.86 × 10−13) and STAT4 (P = 3.37 × 10−9) gene regions as SSc genetic risk factors.

Lipoxin A4 Inhibits IL-1β-Induced IL-6, IL-8, and Matrix Metalloproteinase-3 Production in Human Synovial Fibroblasts and Enhances Synthesis of Tissue Inhibitors of Metalloproteinases

Lipoxins are a novel class of endogenous eicosanoid mediators that potently inhibit inflammatory events by signaling via specific receptors expressed on phagocytic cells. Animal models have shown that lipoxin A4 (LXA4) down-regulates inflammation in vivo. Here we demonstrate, for the first time, the expression of LXA4 receptors, and their up-regulation by IL-1β, in normal human synovial fibroblasts (SF). We examined whether exogenous LXA4 abrogated IL-1β stimulation of SF in vitro. IL-1β induced the synthesis of IL-6, IL-8, and matrix metalloproteinases (MMP)-1 and -3. At nanomolar concentrations, LXA4 inhibited these IL-1β responses with reduction of IL-6 and IL-8 synthesis, by 45 ± 7% and 75 ± 11%, respectively, and prevented IL-1β-induced MMP-3 synthesis without significantly affecting MMP-1 levels. Furthermore, LXA4 induced a 2-fold increase of tissue inhibitor of metalloproteinase (TIMP)-1 and a ∼3-fold increase of TIMP-2 protein levels. LXA4 inhibitory responses were dose dependent and were abrogated by pretreatment with LXA4 receptor antiserum. LXA4-induced changes of IL-6 and TIMP were accompanied by parallel changes in mRNA levels. These results indicate that LXA4 in activated SF inhibits the synthesis of inflammatory cytokines and MMP and stimulates TIMP production in vitro. These findings suggest that LXA4 may be involved in a negative feedback loop opposing inflammatory cytokine-induced activation of SF.

Understanding fibrosis in systemic sclerosis: shifting paradigms, emerging opportunities.

Fibrosis in multiple organs is a prominent pathological finding and distinguishing hallmark of systemic sclerosis (SSc). Findings during the past 5 years have contributed to a more complete understanding of the complex cellular and molecular underpinning of fibrosis in SSc. Fibroblasts, the principal effector cells, are activated in the profibrotic cellular milieu by cytokines and growth factors, developmental pathways, endothelin 1 and thrombin. Innate immune signaling via Toll-like receptors, matrix-generated biomechanical stress signaling via integrins, hypoxia and oxidative stress seem to be implicated in perpetuating the process. Beyond chronic fibroblast activation, fibrosis represents a failure to terminate tissue repair, coupled with an expanded population of mesenchymal cells originating from bone marrow and transdifferentiation of epithelial cells, endothelial cells and pericytes. In addition, studies have identified intrinsic alterations in SSc fibroblasts resulting from epigenetic changes, as well as altered microRNA expression that might underlie the cell-autonomous, persistent activation phenotype of these cells. Precise characterization of the deregulated extracellular and intracellular signaling pathways, mediators and cellular differentiation programs that contribute to fibrosis in SSc will facilitate the development of selective, targeted therapeutic strategies. Effective antifibrotic therapy will ultimately involve novel compounds and repurposing of drugs that are already approved for other indications.

Transforming growth factor |[beta]| as a therapeutic target in systemic sclerosis

Transforming growth factor β (TGF-β) is a pleiotropic cytokine with vital homeostatic functions. Aberrant TGF-β expression is implicated in the pathogenesis of fibrosis in systemic sclerosis (SSc); thus, TGF-β represents a molecular therapeutic target in this disease. Anti-TGF-β monoclonal antibody has been evaluated in a small trial of early SSc, with disappointing results. Antibodies against the αvβ6 integrin that prevent latent TGF-β activation, however, have shown promise in preclinical studies. Small-molecule inhibitors of TGF-β-receptor activity are effective in animal models of fibrosis. Imatinib mesylate and related tyrosine kinase inhibitors also block TGF-β pathways and abrogate fibrotic responses. The blocking of TGF-β activity might lead to spontaneous immune activation, epithelial hyperplasia and impaired wound healing. Loss of immune tolerance is a potential concern in an autoimmune disease such as SSc. Novel insights from microarray-based gene expression analyses and studies of genetic polymorphisms in TGF-β signaling could aid in identifying patients who are most likely to respond to anti-TGF-β treatment. This intervention promises to have a major impact on the treatment of SSc. Concerns regarding efficacy and safety and whether biomarkers can indicate these features, questions regarding appropriate dosing and timing of therapy, and identification of potential responders are critical challenges ahead.

Targeted Disruption of TGF-β/Smad3 Signaling Modulates Skin Fibrosis in a Mouse Model of Scleroderma

Transforming growth factor-beta (TGF-beta) is a potent stimulus of connective tissue accumulation, and is implicated in the pathogenesis of scleroderma and other fibrotic disorders. Smad3 functions as a key intracellular signal transducer for profibrotic TGF-beta responses in normal skin fibroblasts. The potential role of Smad3 in the pathogenesis of scleroderma was investigated in Smad3-null (Smad3(-/-)) mice using a model of skin fibrosis induced by subcutaneous injections of bleomycin. At early time points, bleomycin-induced macrophage infiltration in the dermis and local TGF-beta production were similar in Smad3(-/-) and wild-type mice. In contrast, at day 28, lesional skin from Smad3(-/-) mice showed attenuated fibrosis, lower synthesis and accumulation of collagen, and reduced collagen gene transcription in situ, compared to wild-type mice. Connective tissue growth factor and alpha-smooth muscle actin expression in lesional skin were also significantly attenuated. Electron microscopy revealed an absence of small diameter collagen fibrils in the dermis from bleomycin-treated Smad3(-/-) mice. Compared to fibroblasts derived from wild-type mice, Smad3(-/-) fibroblasts showed reduced in vitro proliferative and profibrotic responses elicited by TGF-beta. Together, these results indicate that ablation of Smad3 is associated with markedly altered fibroblast regulation in vivo and in vitro, and confers partial protection from bleomycin-induced scleroderma in mice. Reduced fibrosis is due to deregulated fibroblast function, as the inflammatory response induced by bleomycin was similar in wild-type and Smad3(-/-) mice.