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Featured researches published by Yackov Berkun.


Annals of the Rheumatic Diseases | 2010

EULAR/PRINTO/PRES criteria for Henoch–Schönlein purpura, childhood polyarteritis nodosa, childhood Wegener granulomatosis and childhood Takayasu arteritis: Ankara 2008. Part II: Final classification criteria

Seza Ozen; Angela Pistorio; Silvia Mirela Iusan; Aysin Bakkaloglu; Troels Herlin; Riva Brik; Antonella Buoncompagni; Calin Lazar; Ilmay Bilge; Yosef Uziel; Donato Rigante; Luca Cantarini; Maria Odete Esteves Hilário; Clovis A. Silva; Mauricio Alegria; Ximena Norambuena; Alexandre Belot; Yackov Berkun; Amparo Ibanez Estrella; Alma Nunzia Olivieri; Maria Giannina Alpigiani; I. Rumba; Flavio Sztajnbok; Lana Tambić-Bukovac; Sulaiman M. Al-Mayouf; Dimitrina Mihaylova; Vyacheslav Chasnyk; Claudia Sengler; Maria Klein-Gitelman; Djamal Djeddi

Objectives To validate the previously proposed classification criteria for Henoch–Schönlein purpura (HSP), childhood polyarteritis nodosa (c-PAN), c-Wegener granulomatosis (c-WG) and c-Takayasu arteritis (c-TA). Methods Step 1: retrospective/prospective web-data collection for children with HSP, c-PAN, c-WG and c-TA with age at diagnosis ≤18 years. Step 2: blinded classification by consensus panel of a representative sample of 280 cases. Step 3: statistical (sensitivity, specificity, area under the curve and κ-agreement) and nominal group technique consensus evaluations. Results 827 patients with HSP, 150 with c-PAN, 60 with c-WG, 87 with c-TA and 52 with c-other were compared with each other. A patient was classified as HSP in the presence of purpura or petechiae (mandatory) with lower limb predominance plus one of four criteria: (1) abdominal pain; (2) histopathology (IgA); (3) arthritis or arthralgia; (4) renal involvement. Classification of c-PAN required a systemic inflammatory disease with evidence of necrotising vasculitis OR angiographic abnormalities of medium-/small-sized arteries (mandatory criterion) plus one of five criteria: (1) skin involvement; (2) myalgia/muscle tenderness; (3) hypertension; (4) peripheral neuropathy; (5) renal involvement. Classification of c-WG required three of six criteria: (1) histopathological evidence of granulomatous inflammation; (2) upper airway involvement; (3) laryngo-tracheo-bronchial involvement; (4) pulmonary involvement (x-ray/CT); (5) antineutrophilic cytoplasmic antibody positivity; (6) renal involvement. Classification of c-TA required typical angiographic abnormalities of the aorta or its main branches and pulmonary arteries (mandatory criterion) plus one of five criteria: (1) pulse deficit or claudication; (2) blood pressure discrepancy in any limb; (3) bruits; (4) hypertension; (5) elevated acute phase reactant. Conclusion European League Against Rheumatism/Paediatric Rheumatology International Trials Organisation/Paediatric Rheumatology European Society propose validated classification criteria for HSP, c-PAN, c-WG and c-TA with high sensitivity/specificity.


The New England Journal of Medicine | 2012

Two Randomized Trials of Canakinumab in Systemic Juvenile Idiopathic Arthritis

Nicolino Ruperto; Hermine I. Brunner; Pierre Quartier; Tamás Constantin; Nico Wulffraat; Gerd Horneff; Riva Brik; Liza McCann; Ozgur Kasapcopur; Lidia Rutkowska-Sak; Rayfel Schneider; Yackov Berkun; Inmaculada Calvo; Muferet Erguven; L. Goffin; Michael Hofer; Tilmann Kallinich; Sheila Knupp Feitosa de Oliveira; Yosef Uziel; Stefania Viola; Kiran Nistala; Carine Wouters; Rolando Cimaz; Manuel A. Ferrandiz; Berit Flatø; Maria Luz Gamir; Isabelle Koné-Paut; Alexei A. Grom; Bo Magnusson; Seza Ozen

BACKGROUND Interleukin-1 is pivotal in the pathogenesis of systemic juvenile idiopathic arthritis (JIA). We assessed the efficacy and safety of canakinumab, a selective, fully human, anti-interleukin-1β monoclonal antibody, in two trials. METHODS In trial 1, we randomly assigned patients, 2 to 19 years of age, with systemic JIA and active systemic features (fever; ≥2 active joints; C-reactive protein, >30 mg per liter; and glucocorticoid dose, ≤1.0 mg per kilogram of body weight per day), in a double-blind fashion, to a single subcutaneous dose of canakinumab (4 mg per kilogram) or placebo. The primary outcome, termed adapted JIA ACR 30 response, was defined as improvement of 30% or more in at least three of the six core criteria for JIA, worsening of more than 30% in no more than one of the criteria, and resolution of fever. In trial 2, after 32 weeks of open-label treatment with canakinumab, patients who had a response and underwent glucocorticoid tapering were randomly assigned to continued treatment with canakinumab or to placebo. The primary outcome was time to flare of systemic JIA. RESULTS At day 15 in trial 1, more patients in the canakinumab group had an adapted JIA ACR 30 response (36 of 43 [84%], vs. 4 of 41 [10%] in the placebo group; P<0.001). In trial 2, among the 100 patients (of 177 in the open-label phase) who underwent randomization in the withdrawal phase, the risk of flare was lower among patients who continued to receive canakinumab than among those who were switched to placebo (74% of patients in the canakinumab group had no flare, vs. 25% in the placebo group, according to Kaplan-Meier estimates; hazard ratio, 0.36; P=0.003). The average glucocorticoid dose was reduced from 0.34 to 0.05 mg per kilogram per day, and glucocorticoids were discontinued in 42 of 128 patients (33%). The macrophage activation syndrome occurred in 7 patients; infections were more frequent with canakinumab than with placebo. CONCLUSIONS These two phase 3 studies show the efficacy of canakinumab in systemic JIA with active systemic features. (Funded by Novartis Pharma; ClinicalTrials.gov numbers, NCT00889863 and NCT00886769.).


The New England Journal of Medicine | 2014

Mutant Adenosine Deaminase 2 in a Polyarteritis Nodosa Vasculopathy

Paulina Navon Elkan; Sarah B. Pierce; Reeval Segel; Thomas J. Walsh; Judith Barash; Shai Padeh; Abraham Zlotogorski; Yackov Berkun; Joseph Press; Masha Mukamel; Isabel Voth; Philip J. Hashkes; Liora Harel; Vered Hoffer; Eduard Ling; Fatoş Yalçınkaya; Ozgur Kasapcopur; Ming K. Lee; Rachel E. Klevit; Paul Renbaum; Ariella Weinberg-Shukron; Elif F. Sener; Barbara Schormair; Sharon Zeligson; Dina Marek-Yagel; Tim M. Strom; Mordechai Shohat; Amihood Singer; Alan Rubinow; Elon Pras

BACKGROUND Polyarteritis nodosa is a systemic necrotizing vasculitis with a pathogenesis that is poorly understood. We identified six families with multiple cases of systemic and cutaneous polyarteritis nodosa, consistent with autosomal recessive inheritance. In most cases, onset of the disease occurred during childhood. METHODS We carried out exome sequencing in persons from multiply affected families of Georgian Jewish or German ancestry. We performed targeted sequencing in additional family members and in unrelated affected persons, 3 of Georgian Jewish ancestry and 14 of Turkish ancestry. Mutations were assessed by testing their effect on enzymatic activity in serum specimens from patients, analysis of protein structure, expression in mammalian cells, and biophysical analysis of purified protein. RESULTS In all the families, vasculitis was caused by recessive mutations in CECR1, the gene encoding adenosine deaminase 2 (ADA2). All the Georgian Jewish patients were homozygous for a mutation encoding a Gly47Arg substitution, the German patients were compound heterozygous for Arg169Gln and Pro251Leu mutations, and one Turkish patient was compound heterozygous for Gly47Val and Trp264Ser mutations. In the endogamous Georgian Jewish population, the Gly47Arg carrier frequency was 0.102, which is consistent with the high prevalence of disease. The other mutations either were found in only one family member or patient or were extremely rare. ADA2 activity was significantly reduced in serum specimens from patients. Expression in human embryonic kidney 293T cells revealed low amounts of mutant secreted protein. CONCLUSIONS Recessive loss-of-function mutations of ADA2, a growth factor that is the major extracellular adenosine deaminase, can cause polyarteritis nodosa vasculopathy with highly varied clinical expression. (Funded by the Shaare Zedek Medical Center and others.).


Pediatrics | 2008

Pediatric Antiphospholipid Syndrome: Clinical and Immunologic Features of 121 Patients in an International Registry

Tadej Avcin; Rolando Cimaz; Earl D. Silverman; Ricard Cervera; Marco Gattorno; Stella Garay; Yackov Berkun; Flavio Sztajnbok; Clovis A. Silva; Lucia M. Campos; Claudia Saad-Magalhães; Donato Rigante; Angelo Ravelli; Alberto Martini; Blaž Rozman; Pier Luigi Meroni

OBJECTIVES. The purpose of this study was to obtain data on the association of antiphospholipid antibodies with clinical manifestations in childhood and to enable future studies to determine the impact of treatment and long-term outcome of pediatric antiphospholipid syndrome. PATIENTS AND METHODS. A European registry extended internationally of pediatric patients with antiphospholipid syndrome was established as a collaborative project of the European Antiphospholipid Antibodies Forum and Lupus Working Group of the Pediatric Rheumatology European Society. To be eligible for enrollment the patient must meet the preliminary criteria for the classification of pediatric antiphospholipid syndrome and the onset of antiphospholipid syndrome must have occurred before the patients 18th birthday. RESULTS. As of December 1, 2007, there were 121 confirmed antiphospholipid syndrome cases registered from 14 countries. Fifty-six patients were male, and 65 were female, with a mean age at the onset of antiphospholipid syndrome of 10.7 years. Sixty (49.5%) patients had underlying autoimmune disease. Venous thrombosis occurred in 72 (60%), arterial thrombosis in 39 (32%), small-vessel thrombosis in 7 (6%), and mixed arterial and venous thrombosis in 3 (2%). Associated nonthrombotic clinical manifestations included hematologic manifestations (38%), skin disorders (18%), and nonthrombotic neurologic manifestations (16%). Laboratory investigations revealed positive anticardiolipin antibodies in 81% of the patients, anti-β2-glycoprotein I antibodies in 67%, and lupus anticoagulant in 72%. Comparisons between different subgroups revealed that patients with primary antiphospholipid syndrome were younger and had a higher frequency of arterial thrombotic events, whereas patients with antiphospholipid syndrome associated with underlying autoimmune disease were older and had a higher frequency of venous thrombotic events associated with hematologic and skin manifestations. CONCLUSIONS. Clinical and laboratory characterization of patients with pediatric antiphospholipid syndrome implies some important differences between antiphospholipid syndrome in pediatric and adult populations. Comparisons between children with primary antiphospholipid syndrome and antiphospholipid syndrome associated with autoimmune disease have revealed certain differences that suggest 2 distinct subgroups.


Arthritis & Rheumatism | 2009

Clinical disease among patients heterozygous for familial mediterranean fever

Dina Marek-Yagel; Yackov Berkun; Shai Padeh; Almogit Abu; Haike Reznik-Wolf; Avi Livneh; Mordechai Pras; Elon Pras

OBJECTIVE To define the molecular basis of familial Mediterranean fever (FMF) in patients with only 1 mutation in the MEFV gene. METHODS Genetic analysis was performed in 20 FMF patients, including full sequencing of complementary DNA (cDNA) samples and multiplex ligation-dependent probe amplification analysis. In patients with first-degree relatives with FMF, haplotype analysis was also performed. RESULTS A second mutation was found in 2 patients. In the other 18 patients, we could not identify additional mutations, large genomic deletions, or duplications. Analysis of single-nucleotide polymorphisms along the cDNA ruled out a lack of expression of 1 of the alleles. In 2 of the 3 families in which more than 1 sibling had FMF, we showed that the affected siblings inherited a different MEFV allele from the parent who did not have the MEFV mutation. CONCLUSION These findings are highly consistent with the existence of a clinical phenotype among some patients who are heterozygous for FMF and could explain the vertical transmission in some families. A single mutation in the MEFV gene may be much more common than was previously thought and may include up to 25% of patients who are diagnosed as having FMF.


Journal of Immunology | 2010

TNF Activates a NF-κB–Regulated Cellular Program in Human CD45RA– Regulatory T Cells that Modulates Their Suppressive Function

Meital Nagar; Jasmine Jacob-Hirsch; Helly Vernitsky; Yackov Berkun; Shomron Ben-Horin; Ninette Amariglio; Ilan Bank; Gideon Rechavi; Itamar Goldstein

Emerging data suggest that regulatory T cell (Treg) dysfunction and consequent breakdown of immunological self-tolerance in autoimmunity can be mediated by factors that are not Treg-intrinsic (e.g., cytokines). Indeed, recent studies show that in rheumatoid arthritis the proinflammatory cytokine TNF reduces the suppressive function of Tregs, whereas in vivo TNF blockade restores this function and accordingly self-tolerance. However, until now a coherent mechanism by which TNF regulates the Treg has not been described. In this paper, we show that TNF induces preferential and significant activation of the canonical NF-κB pathway in human Tregs as compared with CD25– conventional T cells. Furthermore, TNF induced primarily in CD45RA– Tregs a transcription program highly enriched for typical NF-κB target genes, such as the cytokines lymphotoxin-α and TNF, the TNFR superfamily members FAS, 4-1BB, and OX-40, various antiapoptotic genes, and other important immune-response genes. FACS analysis revealed that TNF also induced upregulation of cell surface expression of 4-1BB and OX40 specifically in CD45RA–FOXP3+ Tregs. In contrast, TNF had only a minimal effect on the Treg’s core transcriptional signature or on the intracellular levels of the FOXP3 protein in Tregs. Importantly, TNF treatment modulated the capacity of Tregs to suppress the proliferation and IFN-γ secretion by conventional T cells, an effect that was fully reversed by cotreatment with anti-TNFR2 mAbs. Our findings thus provide new mechanistic insight into the role of TNF and TNFR2 in the pathogenesis of autoimmunity.


Autoimmunity Reviews | 2010

Environmental factors and the geoepidemiology of juvenile idiopathic arthritis

Yackov Berkun; Shai Padeh

Juvenile idiopathic arthritis (JIA), the most common chronic rheumatic disease of childhood, is a clinically heterogeneous group of disorders characterized by chronic inflammatory arthritis. JIA is considered to be an autoimmune disease, which is a result of immune reaction caused or triggered by environmental factors such as infectious agents in a genetically susceptible host. The prevalence of JIA subtypes and different disease manifestations varies geographically. Various infectious agents have been suggested to be a trigger of JIA development. Numerous other factors, such as stressful life events and psychosociologic milieu, meteorological influence and maternal smoking, are suspected to be contributors of multicausal JIA pathogenesis. JIA is probably a basket of diseases rather than a single pathophysiological entity. Being a childhood autoimmune disease it could be viewed as an evolutional process or defect in the maturation of the immune system. Along the lines of the hygiene theory, multiple environment factors could interfere with the appearance and course of JIA, and no single causative factor could be been proven so far. Although many new data on the importance of the environment in JIA etiopathogenesis have appeared, the causal-result association between environmental factors and JIA remains complex and further studies are needed.


International Immunology | 2008

Epigenetic inheritance of DNA methylation limits activation-induced expression of FOXP3 in conventional human CD25−CD4+ T cells

Meital Nagar; Helly Vernitsky; Yoram Cohen; Dan Dominissini; Yackov Berkun; Gideon Rechavi; Ninette Amariglio; Itamar Goldstein

The transcription factor forkhead box P3 (FOXP3 in humans; Foxp3 in mice) controls the development and function of regulatory T cells (Treg). In mice, CD4(+)CD25(-) T cells do not express Foxp3 following TCR activation. Whether FOXP3 is a common activation-induced molecule in human T cells--hence not Treg restricted--is currently a controversial issue. As FOXP3 can significantly modulate the function of T cells, understanding the mode (and regulation) of FOXP3 expression in human T cells is vital. Here we show that in conventional CD4(+)CD25(-) T cells, the induction of FOXP3 expression following TCR activation is both restricted to a fraction of the progeny and transient. Moreover, FOXP3 expression in vivo is particularly infrequent in activated effector CD4(+) T cells that accumulate within inflamed joints. We next demonstrate that the repression of FOXP3 transcription in resting conventional human CD25(-) T cells is linked to complete methylation of an evolutionarily conserved intronic CpG island. The dense methylation pattern is furthermore inherited after activation by progeny. This intronic CpG island, on the other hand, is frequently unmethylated in CD4(+)CD25(+) T cells. Importantly, blocking maintenance DNA methylation, by pharmacological inhibition of DNA methyltransferase-1, induced significant and stable activation-dependent FOXP3 expression in cycling conventional T cells, which was further amplified by co-treatment with transforming growth factor beta. In contrast to natural Treg, such induced CD4(+)FOXP3(+) T cells could produce pro-inflammatory cytokines upon activation. These results indicate that DNA methylation normally restricts FOXP3 transcription in conventional human T cells.


The Journal of Pediatrics | 2010

Familial Mediterranean Fever in the First Two Years of Life: A Unique Phenotype of Disease in Evolution

Shai Padeh; Avi Livneh; Elon Pras; Yael Shinar; Merav Lidar; Olga Feld; Yackov Berkun

OBJECTIVE To characterize the clinical and genetic features of familial Mediterranean fever (FMF). STUDY DESIGN Clinical presentation and MEditerranean FeVer mutation type of all patients with FMF, who first manifested the disease at < or =2 years of age were analyzed and compared with patients who first presented with FMF between 2 and 16 years. RESULTS Of 814 patients with FMF, in 254 patients (31.2%) the first FMF attack was at < or =2 years of age, with a mean age at onset of 1.1 +/- 0.8 years. They were compared with 242 patients who presented with their first manifestation of FMF at 2 to 16 years. The clinical manifestations of FMF were comparable in the 2 patient groups, but the delay of diagnosis was longer in patients with early presentation (3.2 +/- 3.2 years vs.1.9 +/- 2.7 years in the group with onset at 2-16 years, P < .001). A subgroup of patients (60/254), who were diagnosed at < or =2 years had the highest rate of attacks of fever alone as their sole manifestation (40.0% vs 8.4%, P < .05), and less peritonitis (45% vs 86.1%, P < .05) and pleuritis (3.4% vs 32.9%, P < .05). Most of these patients were homozygous for the M694V mutation and were of North African (Sephardic Jewish) extraction. CONCLUSION In early life, FMF often begins with an atypical presentation, characterized by attacks of fever alone, and its diagnosis and initiation of treatment is therefore significantly delayed.


Lupus | 2008

Neuropsychiatric lupus and infectious triggers

Gisele Zandman-Goddard; Yackov Berkun; Ori Barzilai; Mona Boaz; Maya Ram; Juan-Manuel Anaya; Y Shoenfeld

Infections can act as environmental triggers inducing or promoting systemic lupus erythematosus (SLE) in genetically predisposed individuals. The aim of the present study was to compare the titres of antibodies (Abs) to infectious agents with neuropsychiatric (NPSLE) clinical manifestations. The sera of 260 individuals (120 patients with SLE and 140 geographic controls) were evaluated for the titres of Epstein bar virus (EBV), cytomegalovirus (CMV), toxoplasma, rubella and syphilis Abs using the BioPlex 2200 Multiplexed Immunoassay method (BioRad) and by the ELISA method for Helicobacter pylori and Hepatitis B core Ag. All BioPlex 2200 kits used were in developmental stages. Data analysis was performed using SPSS 9.0 statistical analysis software (SPSS Inc., Chicago, IL, USA, 1999). Correlation analysis indicated that rubella IgM Ab titres were marginally, positively associated with psychosis (P = 0.09). No other associations were detected between the 17 infectious Abs and five NP manifestations. When the positivity cut-off for anti-rubella IgM Abs was set at three standard deviations above normal, three positive subjects were identified: one patient with psychosis and one with depression, for a total NPSLE prevalence of 33.3%. On the contrary, the prevalence of NPSLE in the remaining subjects was 6.5%. Marginally significant correlations between elevated titres of rubella IgM Ab with psychosis and depression were found. Although this nearly 5-fold increase is not statistically significant, it appears that in a larger sample size, significance would be reached. This is the first study reported that examined the correlation of NPSLE manifestations with anti-infectious Abs.

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