Novel genetic risk markers for ulcerative colitis in the IL2/IL21 region are in epistasis with IL23R and suggest a common genetic background for ulcerative colitis and celiac disease

OBJECTIVES: Recently, a genome-wide association study showed that single-nucleotide polymorphisms (SNPs) in the chromosome 4q27 region containing IL2 and IL21 are associated with celiac disease. Given the increased prevalence of inflammatory bowel disease (IBD) among celiac disease patients, we investigated the possible involvement of these SNPs in IBD. METHODS: Five SNPs strongly associated with celiac disease within the KIAA1109/TENR/IL2/IL21 linkage disequilibrium block on chromosome 4q27 and one coding SNP within the IL21 gene were analyzed in a large German IBD cohort. The study population comprised a total of 2,948 Caucasian individuals, including 1,461 IBD patients (ulcerative colitis (UC): n=514, Crohn's disease (CD): n=947) and 1,487 healthy unrelated controls. RESULTS: Three of the five celiac disease risk markers had a protective effect on UC susceptibility, and this effect remained significant after correcting for multiple testing: rs6840978: P=0.0082, P(corr)=0.049, odds ratio (OR) 0.77, 95% confidence interval (CI) 0.63-0.93; rs6822844: P=0.0028, P(corr)=0.017, OR 0.73, 95% CI 0.59-0.90; rs13119723: P=0.0058, P(corr)=0.035, OR 0.75, 95% CI 0.61-0.92. A haplotype consisting of the six SNPs tested was markedly associated with UC susceptibility (P=0.0025, P(corr)=0.015, OR 0.72, 95% CI 0.58-0.89). Moreover, in UC, epistasis was observed between the IL23R SNP rs1004819 and three SNPs in the KIAA1109/TENR/IL2/IL21 block (rs13151961, rs13119723, and rs6822844). CONCLUSIONS: Similar to other autoimmune diseases such as celiac disease, rheumatoid arthritis, type 1 diabetes, Graves' disease, and psoriatic arthritis, genetic variation in the chromosome 4q27 region predisposes to UC, suggesting a common genetic background for these diseases.

A1.40 Adiponektin and resistin levels in pregnant patients with rheumatoid arthritis

BACKGROUND Pregnancy induces a modulation of the maternal immune system in order to install tolerance towards the semiallogeneic fetus. This change of the maternal immune systems influences some autoimmune diseases such as rheumatoid arthritis (RA) in a positive way. Our previous study showed that genes of the adipocytokine pathway were differently regulated by pregnancy as well as by RA. The objective of this study was to analyse the association between pregnancy induced improvement of RA and changes of adipocytokine levels. MATERIAL AND METHODS Adiponectin and resistin levels were measured in sera of pregnant (n = 29) and non-pregnant (n = 24) RA patients as well as in pregnant (n = 26) and non-pregnant (n = 9) healthy controls by ELISA. Pregnant RA patients were analysed before conception, once at each trimester and 8 weeks postpartum. Disease activity was measured by CRP and DAS28-CRP. RESULTS Resistin levels were higher in non-pregnant RA patients than in healthy controls. Resistin levels increased during pregnancy and decreased postpartum in both healthy subjects and RA patients. However, RA patients with active disease during pregnancy showed higher resistin levels at the third trimester than healthy women. There was a positive correlation between resistin levels and CRP. Adiponektin levels increased at the second trimester of pregnancy and decreased thereafter in both healthy subject and RA patients. There was no difference between patients and healthy subjects. Adiponektin levels of RA patients negatively correlated with CRP. CONCLUSION Pregnancy induces an increase of both the resistin and the adiponectin levels. Resistin levels are further influenced by active disease. By contrast, the increase of the adiponectin levels at the second trimester might play a role in the modulation of disease activity of RA.

Deciphering microRNA code in pain and inflammation: lessons from bladder pain syndrome

MicroRNAs (miRNAs), a novel class of molecules regulating gene expression, have been hailed as modulators of many biological processes and disease states. Recent studies demonstrated an important role of miRNAs in the processes of inflammation and cancer, however, there are little data implicating miRNAs in peripheral pain. Bladder pain syndrome/interstitial cystitis (BPS/IC) is a clinical syndrome of pelvic pain and urinary urgency/frequency in the absence of a specific cause. BPS is a chronic inflammatory condition that might share some of the pathogenetic mechanisms with its common co-morbidities inflammatory bowel disease (IBD), asthma and autoimmune diseases. Using miRNA profiling in BPS and the information about validated miRNA targets, we delineated the signaling pathways activated in this and other inflammatory pain disorders. This review projects the miRNA profiling and functional data originating from the research in bladder cancer and immune-mediated diseases on the BPS-specific miRNAs with the aim to gain new insight into the pathogenesis of this enigmatic disorder, and highlighting the common regulatory mechanisms of pain and inflammation.

Kindlin-3 regulates integrin activation and adhesion reinforcement of effector T cells

Activated T cells use very late antigen-4/α4β1 integrin for capture, rolling on, and firm adhesion to endothelial cells, and use leukocyte function-associated antigen-1/αLβ2 integrin for subsequent crawling and extravasation. Inhibition of α4β1 is sufficient to prevent extravasation of activated T cells and is successfully used to combat autoimmune diseases, such as multiple sclerosis. Here we show that effector T cells lacking the integrin activator Kindlin-3 extravasate and induce experimental autoimmune encephalomyelitis in mice immunized with autoantigen. In sharp contrast, adoptively transferred autoreactive T cells from Kindlin-3-deficient mice fail to extravasate into the naïve CNS. Mechanistically, autoreactive Kindlin-3-null T cells extravasate when the CNS is inflamed and the brain microvasculature expresses high levels of integrin ligands. Flow chamber assays under physiological shear conditions confirmed that Kindlin-3-null effector T cells adhere to high concentrations of vascular cell adhesion molecule-1 and intercellular adhesion molecule-1, albeit less efficiently than WT T cells. Although these arrested T cells polarize and start crawling, only few remain firmly adherent over time. Our data demonstrate that the requirement of Kindlin-3 for effector T cells to induce α4β1 and αLβ2 integrin ligand binding and stabilization of integrin-ligand bonds is critical when integrin ligand levels are low, but of less importance when integrin ligand levels are high.

Sex Differences in the Gut Microbiome Drive Hormone-Dependent Regulation of Autoimmunity

Microbial exposures and sex hormones exert potent effects on autoimmune diseases, many of which are more prevalent in women. We demonstrate that early-life microbial exposures determine sex hormone levels and modify progression to autoimmunity in the nonobese diabetic (NOD) mouse model of type 1 diabetes (T1D). Colonization by commensal microbes elevated serum testosterone and protected NOD males from T1D. Transfer of gut microbiota from adult males to immature females altered the recipient's microbiota, resulting in elevated testosterone and metabolomic changes, reduced islet inflammation and autoantibody production, and robust T1D protection. These effects were dependent on androgen receptor activity. Thus, the commensal microbial community alters sex hormone levels and regulates autoimmune disease fate in individuals with high genetic risk.

CD40 activation induces NREM sleep and modulates genes associated with sleep homeostasis

The T-cell derived cytokine CD40 ligand is overexpressed in patients with autoimmune diseases. Through activation of its receptor, CD40 ligand leads to a tumor necrosis factor (TNF) receptor 1 (TNFR1) dependent impairment of locomotor activity in mice. Here we report that this effect is explained through a promotion of sleep, which was specific to non-rapid eye movement (NREM) sleep while REM sleep was suppressed. The increase in NREM sleep was accompanied by a decrease in EEG delta power during NREM sleep and by a decrease in the expression of transcripts in the cerebral cortex known to be associated with homeostatic sleep drive, such as Homer1a, Early growth response 2, Neuronal pentraxin 2, and Fos-like antigen 2. The effect of CD40 activation was mimicked by peripheral TNF injection and prevented by the TNF blocker etanercept. Our study indicates that sleep-wake dysregulation in autoimmune diseases may result from CD40 induced TNF:TNFR1 mediated alterations of molecular pathways, which regulate sleep-wake behavior.

Different IVIG glycoforms affect in vitro inhibition of anti-ganglioside antibody-mediated complement deposition

Intravenous immunoglobulin (IVIG) is the first line treatment for Guillain–Barré syndrome and multifocal motor neuropathy, which are caused by anti-ganglioside antibody-mediated complement-dependent cytotoxicity. IVIG has many potential mechanisms of action, and sialylation of the IgG Fc portion reportedly has an anti-inflammatory effect in antibody-dependent cell-mediated cytotoxicity models. We investigated the effects of different IVIG glycoforms on the inhibition of antibody-mediated complement-dependent cytotoxicity. Deglycosylated, degalactosylated, galactosylated and sialylated IgG were prepared from IVIG following treatment with glycosidases and glycosyltransferases. Sera from patients with Guillain–Barré syndrome, Miller Fisher syndrome and multifocal motor neuropathy associated with anti-ganglioside antibodies were used. Inhibition of complement deposition subsequent to IgG or IgM autoantibody binding to ganglioside, GM1 or GQ1b was assessed on microtiter plates. Sialylated and galactosylated IVIGs more effectively inhibited C3 deposition than original IVIG or enzyme-treated IVIGs (agalactosylated and deglycosylated IVIGs). Therefore, sialylated and galactosylated IVIGs may be more effective than conventional IVIG in the treatment of complement-dependent autoimmune diseases.

Effect of IgG for intravenous use on Fc receptor-mediated phagocytosis by human monocytes

Polyspecific IgG given intravenously at high doses (IVIG) is used for immunomodulatory therapy in autoimmune diseases such as idiopathic thrombocytopenic purpura and myasthenia gravis. It is assumed that the clinical effect is brought about in part by a modulation of mononuclear phagocyte function, in particular by an inhibition of Fc receptor (FcR) mediated phagocytosis. In the present study, the effect of IVIG on FcR-mediated phagocytosis by monocytes was analysed in vitro. Since monocytes exposed to minute amounts of surface-bound IgG displayed impaired phagocytosis of IgG-coated erythrocytes (EA), the effect of IVIG was studied with mononuclear cells suspended in teflon bags in medium containing 10% autologous serum and IVIG (2-10 mg/ml). Monocytes pre-exposed to IVIG and then washed, displayed impaired ingestion of EA when compared with control cells cultured in 10% autologous serum only. The decrease in phagocytosis was observed with sheep erythrocytes treated with either rabbit IgG or bovine IgG1 and with anti-D-treated human erythrocytes. This suggests that phagocytosis via both FcR type I (FcRI) and type II (FcRII) was decreased. The impairment of phagocytosis was dependent on the presence of intact IgG and was mediated by IVIG from nulliparous donors and from multigravidae to the same extent, suggesting that alloantibodies contained in IVIG have a minor role in modulating FcR-mediated phagocytosis by monocytes. A flow cytometric analysis using anti-FcRI, FcRII and FcRII monoclonal antibodies showed that IVIG treatment upregulated FcRI expression but did not significantly alter the expression of FcRII and FcRIII.

Double seronegative myasthenia gravis with antiphospholipid syndrome: a case report

INTRODUCTION Myasthenia gravis is an autoimmune disease characterized by fluctuating muscle weakness. It is often associated with other autoimmune disorders, such as thyroid disease, rheumatoid arthritis, systemic lupus erythematosus, and antiphospholipid syndrome. Many aspects of autoimmune diseases are not completely understood, particularly when they occur in association, which suggests a common pathogenetic mechanism. CASE PRESENTATION We report a case of a 42-year-old Caucasian woman with antiphospholipid syndrome, in whom myasthenia gravis developed years later. She tested negative for both antibodies against the acetylcholine receptor and against muscle-specific receptor tyrosine-kinase, but had typical decremental responses at the repetitive nerve stimulation testing, so that a generalized myasthenia gravis was diagnosed. Her thromboplastin time and activated partial thromboplastin time were high, anticardiolipin and anti-β2 glycoprotein-I antibodies were slightly elevated, as a manifestation of the antiphospholipid syndrome. She had a good clinical response when treated with a combination of pyridostigmine, prednisone and azathioprine. CONCLUSIONS Many patients with myasthenia gravis test positive for a large variety of auto-antibodies, testifying of an immune dysregulation, and some display mild T-cell lymphopenia associated with hypergammaglobulinemia and B-cell hyper-reactivity. Both of these mechanisms could explain the occurrence of another autoimmune condition, such as antiphospholipid syndrome, but further studies are necessary to shed light on this matter.Clinicians should be aware that patients with an autoimmune diagnosis such as antiphospholipid syndrome who develop signs and neurological symptoms suggestive of myasthenia gravis are at risk and should prompt an emergent evaluation by a specialist.

A highly conserved interspecies V(H) in the human genome.

Idiotype conservation between human and mouse antibodies has been observed in association with various infectious and autoimmune diseases. We have isolated a human anti-idiotypic antibody to a mouse monoclonal anti-IgE antibody (BSW17) suggesting a conserved interspecies idiotype associated with an anti-IgE response. To find the homologue of BSW17 in the human genome we applied the guided selection strategy. Combining V(H) of BSW17 with a human V(L) repertoire resulted in three light chains. The three V(L) chains were then combined with a human V(H) repertoire resulting in three clones specific for human IgE. Surprisingly, one clone, Hu41, had the same epitope specificity and functional in vitro activity as BSW17 and V(H) complementarity-determining regions identical with that of BSW17. Real-time PCR analysis confirmed the presence of the Hu41 V(H) sequence in the human genome. These data document the first example of the isolation of a human antibody where high sequence similarity to the original murine V(H) sequence is associated with common antigen and epitope specificity.

EAACI IG Biologicals task force paper on the use of biologic agents in allergic disorders.

Biologic agents (also termed biologicals or biologics) are therapeutics that are synthesized by living organisms and directed against a specific determinant, for example, a cytokine or receptor. In inflammatory and autoimmune diseases, biologicals have revolutionized the treatment of several immune-mediated disorders. Biologicals have also been tested in allergic disorders. These include agents targeting IgE; T helper 2 (Th2)-type and Th2-promoting cytokines, including interleukin-4 (IL-4), IL-5, IL-9, IL-13, IL-31, and thymic stromal lymphopoietin (TSLP); pro-inflammatory cytokines, such as IL-1β, IL-12, IL-17A, IL-17F, IL-23, and tumor necrosis factor (TNF); chemokine receptor CCR4; and lymphocyte surface and adhesion molecules, including CD2, CD11a, CD20, CD25, CD52, and OX40 ligand. In this task force paper of the Interest Group on Biologicals of the European Academy of Allergy and Clinical Immunology, we review biologicals that are currently available or tested for the use in various allergic and urticarial pathologies, by providing an overview on their state of development, area of use, adverse events, and future research directions.

Inhibition and deficiency of the immunoproteasome subunit LMP7 attenuates LCMV-induced meningitis

In addition to antigen processing, immunoproteasomes were recently shown to exert functions influencing cytokine production by monocytes and T cells, T-helper cell differentiation, and T-cell survival. Moreover, selective inhibition of the immunoproteasome subunit LMP7 ameliorated symptoms of autoimmune diseases including CD4(+) T-cell mediated EAE. In this study, we show that LMP7 also plays a crucial role in the pathogenesis of lymphocytic choriomeningitis virus (LCMV)-induced meningitis mediated by CTLs. Mice lacking functional LMP7 display delayed and reduced clinical signs of disease accompanied by a strongly decreased inflammatory infiltration into the brain. Interestingly, we found that selective inhibition and genetic deficiency of LMP7 affect the pathogenesis of LCMV-induced meningitis in a distinct manner. Our findings support the important role of LMP7 in inflammatory disorders and suggest immunoproteasome inhibition as a novel strategy against inflammation-induced neuropathology in the CNS.

Antifactor Xa Activity for the Management of Anticoagulation during Cardiac Surgery

Background In patients with autoimmune diseases associated with antiphospholipid antibodies, precise management of anticoagulation during extracorporeal circulation (ECC) is complicated. It was the aim of the present study to determine whether antifactor Xa (aXa) activity is useful in guiding heparin therapy during ECC. Methods In 15 patients undergoing cardiac surgery, anticoagulation with unfractionated heparin (UFH) and its reversal with protamine were guided using activated clotting time (ACT) (>400 second during ECC; ≤100 second for UFH reversal). For each ACT, the corresponding aXa activity levels were measured. Results A total of 144 blood samples were obtained. ACT and aXa activity were significantly correlated (r = 0.771, p< 0.0001, Spearman rank-order correlation). Using receiver operating characteristic curve (ROC) analyses, the cutoffvalues for aXa activity were 1.14 IU/mL (area under the ROC curve [AUC]: 0.89; inaccuracy rate: 9.4%) to predict ACT > 400 seconds and 0.55 IU/mL (AUC: 0.85; inaccuracy rate: 13.3%) for ACT ≤ 100 seconds. Conclusion AXa activity is strongly correlated with ACT, and therefore may be feasible for managing anticoagulation with UFH during ECC.

Pregnancy and reproduction in autoimmune rheumatic diseases

Despite evidence for the important role of oestrogens in the aetiology and pathophysiology of chronic immune/inflammatory diseases, the previous view of an unequivocal beneficial effect of oestrogens on RA compared with a detrimental effect on SLE has to be reconsidered. Likewise, the long-held belief that RA remits in the majority of pregnant patients has been challenged, and shows that only half of the patients experience significant improvement when objective disease activity measurements are applied. Pregnancies in patients with SLE are mostly successful when well planned and monitored interdisciplinarily, whereas a small proportion of women with APS still have adverse pregnancy outcomes in spite of the standard treatment. New prospective studies indicate better outcomes for pregnancies in women with rare diseases such as SSc and vasculitis. Fertility problems are not uncommon in patients with rheumatic disease and need to be considered in both genders. Necessary therapy, shortly before or during the pregnancy, demands taking into account the health of both mother and fetus. Long-term effects of drugs on offspring exposed in utero or during lactation is a new area under study as well as late effects of maternal rheumatic disease on children.