Overlap between differentially methylated DNA regions in blood B lymphocytes and genetic at-risk loci in primary Sjögren's syndrome

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Deregulation of microRNA expression in purified T and B lymphocytes from patients with primary Sjogren's syndrome

International audienceAbstract Objective MicroRNAs (miRNAs) play an important role in the pathogenesis of autoimmune diseases such as primary Sjögren’s syndrome (pSS). This study is the first to investigate miRNA expression patterns in purified T and B lymphocytes from patients with pSS using a high-throughput quantitative PCR (qPCR) approach. Methods Two independent cohorts of both patients with pSS and controls, one for discovery and one for replication, were included in this study. CD4+ T cells and CD19+ B cells were isolated from peripheral blood mononuclear cells by magnetic microbeads and expression of miRNAs was profiled using the Exiqon Human miRNome panel I analysing 372 miRNAs. A selection of differentially expressed miRNAs was replicated in the second cohort using specific qPCR assays. Results A major difference in miRNA expression patterns was observed between the lymphocyte populations from patients with pSS and controls. In CD4 T lymphocytes, hsa-let-7d-3p, hsa-miR-155–5 p, hsa-miR-222–3 p, hsa-miR-30c-5p, hsa-miR-146a-5p, hsa-miR-378a-3p and hsa-miR-28–5 p were significantly differentially expressed in both the discovery and the replication cohort. In B lymphocytes, hsa-miR-378a-3p, hsa-miR-222–3 p, hsa-miR-26a-5p, hsa-miR-30b-5p and hsa-miR-19b-3p were significantly differentially expressed. Potential target mRNAs were enriched in disease relevant pathways. Expression of B-cell activating factor (BAFF) mRNA was inversely correlated with the expression of hsa-miR-30b-5p in B lymphocytes from patients with pSS and functional experiments showed increased expression of BAFF after inhibiting hsa-miR-30b-5p. Conclusions This study demonstrates major miRNAs deregulation in T and B cells from patients with pSS in two independent cohorts, which might target genes known to be involved in the pathogenesis of pSS

Increased Dickkopf-1 in Recent-onset Rheumatoid Arthritis is a New Biomarker of Structural Severity. Data from the ESPOIR Cohort

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Salivary gland epithelial cells from patients with Sjögren's syndrome induce B-lymphocyte survival and activation

International audienceObjectives: Primary Sjögren's syndrome (pSS) is characterized by chronic hyperactivation of Blymphocytes. Salivary gland epithelial cells (SGECs) could play a role in promoting Blymphocyte activation within the target tissue. We aimed to study the interactions between SGECs from pSS patients or controls and B-lymphocytes. Methods: Patients had pSS according to 2016 EULAR/ACR criteria. Gene expression analysis of SGECs and B-lymphocytes from pSS and controls isolated from salivary gland biopsies and blood was performed by RNA-seq. SGECs from pSS and controls were co-cultured with Blymphocytes sorted from healthy donor blood and stimulated. Transwell and inhibition experiments were performed. Results: Gene expression analysis of SGECs identified an upregulation of interferon signaling pathway and genes involved in immune responses (HLA-DRA, IL7, BAFFR) in pSS. Activation genes CD40 and CD48 were upregulated in salivary gland sorted B-lymphocytes from pSS patients. SGECs induced an increase in B-lymphocyte survival, which was higher for SGECs from pSS patients than controls. Moreover, when stimulated with Poly(I:C), SGECs from pSS patients induced higher activation of B-lymphocytes than those from controls. This effect depended on soluble factors. Inhibition with anti-BAFF, anti-APRIL, anti-IL6-R antibodies JAK1/3 inhibitor, or hydroxychloroquine had no effect, conversely to leflunomide, BTK or PI3K inhibitors. Conclusions: SGECs from patients with pSS had better ability than those from controls to induce survival and activation of B-lymphocytes. Targeting a single cytokine did not inhibit this effect, whereas, leflunomide, BTK or PI3K inhibitors partially decreased B-lymphocytes viability in this model. This gives indications for future therapeutic options in pSS

Germline variation of TNFAIP3 in primary Sjögren's syndrome-associated lymphoma: Table 1

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Germline variation of TNFAIP3 in primary Sjögren's syndrome-associated lymphoma: Table 1

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Role of the IL-12/IL-35 balance in patients with Sjögren syndrome

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Increase in Dickkopf-1 Serum Level in Recent Spondyloarthritis. Data from the DESIR Cohort

International audienceObjectives : To investigate DKK-1 and SOST serum levels among patients with recent inflammatory back pain (IBP) fulfilling ASAS criteria for SpA and associated factors.Methods : The DESIR cohort is a prospective, multicenter French cohort of 708 patients with early IBP (duration >3 months and <3 years) suggestive of AxSpA. DKK-1 and SOST serum levels were assessed at baseline and were compared between the subgroup of patients fulfilling ASAS criteria for SpA (n = 486; 68.6%) and 80 healthy controls.Results : Mean SOST serum levels were lower in ASAS+ patients than healthy controls (49.21 ± 25.9 vs. 87.8 ± 26 pmol/L; p<0.0001). In multivariate analysis, age (p = 5.4 10−9), CRP level (p<0.0001) and serum DKK-1 level (p = 0.001) were associated with SOST level. Mean DKK-1 serum levels were higher in axial SpA patients than controls (30.03 ± 15.5 vs. 11.6 ± 4.2 pmol/L; p<0.0001). In multivariate analysis, DKK-1 serum levels were associated with male gender (p = 0.03), CRP level (p = 0.006), SOST serum level (p = 0.002) and presence of sacroiliitis on radiography (p = 0.05). Genetic association testing of 10 SNPs encompassing the DKK-1 locus failed to demonstrate a significant contribution of genetics to control of DKK-1 serum levels.Conclusions : DKK-1 serum levels were increased and SOST levels were decreased among a large cohort of patients with early axial SpA compared to healthy controls. DKK-1 serum levels were mostly associated with biological inflammation and SOST serum levels

Germline and somatic genetic variations of TNFAIP3 in lymphoma complicating primary Sjogren's syndrome.

International audienceSeveral autoimmune diseases, including primary Sjögren's syndrome (pSS), are associated with an increased risk for lymphoma. Polymorphisms of TNFAIP3, which encodes the A20 protein that plays a key role in controlling nuclear factor κB activation, have been associated with several autoimmune diseases. Somatic mutations of TNFAIP3 have been observed in the mucosa-associated lymphoid tissue lymphoma subtype frequently associated with pSS. We studied germline and somatic abnormalities of TNFAIP3 in 574 patients with pSS, including 25 with lymphoma. Nineteen additional patients with pSS and lymphoma were available for exome sequence analysis. Functional abnormalities of A20 were assessed by gene reporter assays. The rs2230926 exonic variant was associated with an increased risk for pSS complicated by lymphoma (odds ratio, 3.36 [95% confidence interval, 1.34-8.42], and odds ratio, 3.26 [95% confidence interval, 1.31-8.12], vs controls and pSS patients without lymphoma, respectively; P = .011). Twelve (60%) of the 20 patients with paired germline and lymphoma TNFAIP3 sequence data had functional abnormalities of A20: 6 in germline DNA, 5 in lymphoma DNA, and 1 in both. The frequency was even higher (77%) among pSS patients with mucosa-associated lymphoid tissue lymphoma. Some of these variants showed impaired control of nuclear factor κB activation. These results support a key role for germline and somatic variations of A20 in the transformation between autoimmunity and lymphoma