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Objective.To determine the prevalence of the most often tested autoantibodies in synovitis, acne, pustulosis, hyperostosis, and osteitis (SAPHO) syndrome.Methods.We identified 90 patients seen in our unit between June 2002 and June 2009, and diagnosed according to the proposed criteria for SAPHO syndrome. Demographic and clinical data were collected as well as immunological results, including antinuclear, antithyroid peroxydase (TPO), antithyroid globulin (Tg), antigastric parietal cell, antismooth muscle, antimitochondria, and anti-liver-kidney microsome (LKM) antibodies. Anticyclic citrullinated peptide (CCP) antibodies were analyzed in 69 patients, antibodies to soluble extractable nuclear antigens in 43, anti-double-stranded DNA (dsDNA) antibodies in 22 [depending on the type of fluorescence of antinuclear antibody (ANA)], and antiendomysium antibodies in 55.ResultsAutoantibodies were found in 20 patients (22.2%): 14 patients (15.5%) had positive ANA (titer ≥ 1/160); among them, 10 (11%) patients never took a lupus-inducing drug. Antithyroid antibodies (anti-TPO and/or anti-Tg antibodies) were found in only 3 patients (3.3%). Three patients (3.3%) were positive for antigastric parietal cell antibodies and 4 (4.4%) were weakly positive for antismooth muscle antibodies. Antimitochondria and LKM antibodies were negative in all 90 patients. Anti-CCP and anti-dsDNA antibodies were negative in the 69 and 22 patients tested, respectively. One out of 43 patients (2.3%) had anti-SSA antibodies. Antiendomysium antibodies were negative in the 55 patients tested.Conclusion.Our study indicates an increased prevalence of autoantibodies in SAPHO syndrome, with no specific profile. We failed to confirm the reports of an increased prevalence of antithyroid antibodies. These results tend to support a link between autoimmunity and SAPHO syndrome.

Background Rheumatoid arthritis (RA) is a multifactorial disease, which is likely associated with the effects of environmental and genetic factors. The PTPN22 rs2476601 variant has been unambiguously identified as a RA risk genetic factor. PTPN22 encodes the lymphoid specific phosphatase Lyp that affects the responsiveness of T and B cell receptors. However, to date, its role in the activation of neutrophils NADPH oxidase remains undetermined. Objectives To study the role of Lyp in neutrophils, particularly the activation and the priming, of NADPH oxidase in healthy donors. Methods Neutrophils will be isolated from the blood of healthy donors using the Dextran-Ficoll gradient techniques. Lyp mRNA will be analyzed by quantitative real time PCR. Expression and localization of Lyp will be detected by SDS-PAGE, Western Blot techniques and confocal microscopy. The effects of the TNFα will be investigated. The signaling pathways implicated in activation of the NADPH oxidase will be analyzed by SDS-PAGE and Western Blots techniques. The protein targets of LYP will be analyzed by co-immunoprecipitation. The role of Lyp in reactive oxygen species (ROS) production by neutrophils will be determined by using two Lyp inhibitors. ROS production will be measured by luminol-amplified chemo-luminescence, NADPH activation will be measured by the cytochrome c reduction assay. Results Lyp is expressed in resting human neutrophils. With TNFα, Lyp expression increase and Lyp translocates to the membrane. Two Lyp inhibitors inhibit the production of ROS and anion superoxyde (O2°-) in human neutrophils stimulated with fMLF alone and when they are primed by TNFα. They have no effect on degranulation. Lyp inhibitors also inhibit the phosphorylation of ERK1/2 after stimulation with TNFα, and the phosphorylation of p47phox induced by fMLF. Conclusions The tyrosine phosphatase Lyp could have a NADPH oxidase activator role in human neutrophils. Lyp is involved in the activation of ERK1/2 and p47phox phosphorylation. Lyp inhibitors could have anti-inflammatory effects in RA. Disclosure of Interest None declared

Background The Synovitis, Acne, Pustulosis, Hyperostosis and Osteitis (SAPHO) syndrome is a rare autoinflammatory disorder of skin and bone that can be classified with the inflammatory spondyloarthropathies (1). Genetic predisposing factors for SAPHO syndrome have been long suspected because of (i) reported familial clustering of the syndrome - although most cases are sporadic - (2), and (ii) the existence of two mouse models of the syndrome (the cmo and Lupo strains), each with a different spontaneous recessive mutation in the Pstpip2 gene (3,4). Previous studies excluded a role for the genes PSTPIP2 , LPIN, NOD2 , IL1RL2 , IL1RN , IL36RN and SIGLEC15 in the pathogenesis of the syndrome (5,6). Objectives Identify and validate candidate genes involved in the pathogenesis of familial SAPHO syndrome by performing whole-exome sequencing (WES) of affected subjects and unaffected relatives. Methods We investigated a cohort of 44 SAPHO subjects that includes 5 families segregating the syndrome. After obtaining written informed consent, we extracted DNA from peripheral blood samples by using automated magnetic-bead technology (Chemagen). Exomes captured with Agilent SureSelect V5+UTR kit were subjected to paired-end sequencing on an Illumina HiSeq200 sequencer (Sistemas Genόmicos). Candidate genes and putatively pathogenic variants were identified by using Variant Analysis software (Ingenuity). Validation was undertaken by Sanger sequencing, segregation analysis and functional assays when appropriate. Results We identified several potentially pathogenic variants in our cohort in genes whose products are potentially involved in the pathogenesis of SAPHO syndrome. In affected subjects we also found variants known to predispose to autoinflammatory/autoimmune disease in genes such as NOD2 / CARD15 . Conclusions WES is a very powerful tool to investigate the genetic factors underlying rare inherited autoinflammatory disorders that cannot be analyzed by classical genetic methods such as positional cloning. References 1. Clin Exp Rheumatol 1988; 6: 109-112. 2. Joint Bone Spine 2007; 74: 123-126. 3. Bone 2006; 38: 41-47. 4. Blood 2006, 107; 3350-3358. 5. J Rheumatol 2010; 37; 401-409. 6. Ann Rheumat Dis 2013; 72 - Suppl 3; 169. Disclosure of Interest : None declared DOI 10.1136/annrheumdis-2014-eular.4251

International audience; Objective To evaluate the contribution of the SPP1 rs11439060 and rs9138 polymorphisms, previously reported as autoimmune risk variants, in the RA genetic background according to anti-citrullinated protein antibodies (ACPAs) status of RA individuals. Methods We analyzed a total of 11,715 RA cases and 26,493 controls from 9 independent cohorts, all individuals were genotyped or had imputed genotypes for SPP1 rs11439060 and rs9138. The effect of the SPP1 rs11439060 and rs9138 risk-allele combination on OPN expression in macrophages and OPN serum levels was investigated. Results We provide evidence for a distinct contribution of SPP1 to RA susceptibility according to ACPA status: the combination of ≥ 3 SPP1 rs11439060 and rs9138 common alleles was associated mainly with ACPA negativity (P = 1.29x10-5, ORACPA-negative 1.257 1.135–1.394) and less with ACPA positivity (P = 0.0148, ORACPA-positive 1.072 1.014–1.134]). The odds ratios between these subgroups (i.e., ACPA-positive and -negative) significantly differed (P = 7.33x10-3). Expression quantitative trait locus analysis revealed an association of the SPP1 risk-allele combination with decreased SPP1 expression in peripheral macrophages from 599 individuals. To corroborate these findings, we found an association of the SPP1 risk-allele combination and low serum level of secreted OPN (P = 0.0157) as well as serum level of secreted OPN correlated positively with ACPA production (P = 0.005; r = 0.483). Conclusion We demonstrate a significant contribution of the combination of SPP1 rs11439060 and rs9138 frequent alleles to risk of RA, the magnitude of the association greater in patients negative for ACPAs.

Background The Synovitis, Acne, Pustulosis, Hyperostosis and Osteitis (SAPHO) syndrome is currently considered as an autoinflammatory disorder of bone and skin that can be classified with the inflammatory spondyloarthropathies (1). Genetic predisposing factors for SAPHO syndrome have been long suspected because of reported familial clustering of the syndrome, although most cases are sporadic (2). Additional support for a genetic origin of the syndrome is provided by a murine model (the cmo mouse) that carries a spontaneous recessive mutation in the Pstpip2 gene (3). However, previous studies excluded a role for the genes PSIPT2 , LPIN and NOD2 in the pathogenesis of the syndrome (4). Two rare autoinflammatory disorders, DIRA and DITRA syndromes, have been related to a genetic deficiency in interleukin-1 (IL-1) and IL-36 receptor antagonists, respectively (5-7). These two conditions, particularly DIRA syndrome, share some features with SAPHO syndrome. Objectives We investigated the possible role of the genes encoding IL-1 receptor antagonist ( IL1RN ), IL-36 receptor ( IL36R ), IL-36 receptor antagonist ( IL36RN ) and cell-surface lectin Siglec-15 ( SIGLEC15 ) in the pathogenesis of SAPHO syndrome. Methods The study was performed on a cohort of 40 SAPHO syndrome subjects that includes 3 familial cases. After obtaining written informed consent, we extracted DNA from peripheral blood samples by using automated magnetic-bead technology (Chemagen). We PCR-amplified and sequenced all exons and intron-exon boundaries of the four candidate genes. In addition, we carried out a genome-wide copy-number variation (CNV) analysis on SNP arrays (Illumina BeadStudio array of 2.5 million SNPs). Results We did not identify any pathogenic mutations in the IL1RN , IL36R , IL36RN and SIGLEC15 genes, although we did detect known polymorphic variations. Heterozygosity and CNV analyses excluded any deletions of the candidate genes in our cohort. Conclusions We found no involvement of the IL1RN , IL36R , IL36RN and SIGLEC15 genes in the pathogenesis of SAPHO syndrome. References Clin Exp Rheumatol 1988; 6 : 109-112. Joint Bone Spine 2007; 74 : 123-126. Bone 2006; 38 : 41-47. J Rheumatol 2010; 37 : 401-409. N Engl J Med 2009; 360 : 2426-2437. N Engl J Med 2011; 365 :620–628. Am J Hum Genet 2011; 89 : 432–437. Acknowledgements T.C. was a recipient of an “Ayuda Predoctoral” fellowship from CIBERER. This work was supported by grant FIS PI11/00283 from ISCIII (to F.J.d.C.). Disclosure of Interest None Declared

Methods: MRNAs obtained from PBMCs were stimulated by LPS or left un-stimulated for 4h. We first used the Affymetrix Human Exon Array to analyze regulation of 14,851 and 15,334 expressed genes out of the 32,778 on the array in four patients and four ‘healthy’ subjects respectively. Results were validated using RTqPCR to measure expression of 63 genes of interest in a prospective cohort of 57 patients and 9 ‘healthy’ subjects. Results: Gene profiling revealed a core of 741 genes that were similarly regulated by LPS in cirrhotic and ‘healthy’ PBMCs. Among them, 300 LPS-induced genes were enriched in GO categories ‘regulation of mononuclear cell proliferation’ and ‘cytokine activity’. 441 shared LPS-downregulated genes were involved in recognition of PAMPs, chemotaxis, cell migration and lysosome suggesting that LPS-induced immune paralysis is a universal response. Comparison of functions associated with the 1,356 genes that were specifically regulated by LPS in cirrhotic cells to functions of the 1,049 genes specifically regulated in ‘healthy’ cells allowed to define a cirrhosis specific phenotype. Unlike healthy cells, LPS-stimulated cirrhotic cells did not exhibit the interferon (type I and II)-mediated program (e.g. IRF1, IRF2, IRF7, IFNG, IFI6, STAT1, STAT2, IFITM2), which is critical for immune host defense and resolution of inflammation. Consistent with these results, CXCL10 and CXCL11, two interferoninduced chemokines were induced by LPS in ‘healthy’ but not in cirrhotic PBMCs. Moreover, LPS-stimulated cirrhotic cells had downregulation of endocytic trafficking genes, which may results in decreased TLR4 endocytosis and inhibition of TRIF-mediated interferon pathway. Conclusions: Both LPS-stimulated cirrhotic and ‘healthy’ PBMCs exhibit features of immune paralysis. Moreover, LPS stimulated cirrhotic PBMCs have a specific defect of induction of interferon target genes involved in host defense and resolution of inflammation. These findings may explain the severity of bacterial infections in cirrhosis.