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ID PMID Title PublicationDate abstract
25466873 Immuno-proteomics: Development of a novel reagent for separating antibodies from their tar 2015 Jun Immunoprecipitation (IP) is a widely used technique for identifying the binding partners of the target proteins of specific antibodies. Putative binding targets and their partners are usually in much lower amounts than the antibodies used to capture these target proteins. Thus antigen identification using proteomics following IP is often confounded by the presence of an overwhelming amount of interfering antibody protein. Even covalently linking antibodies to beads is susceptible to antibody leaching during IP. To circumvent this interference, we describe here a reagent, called Biotin-CDM that reversibly tags all potential target proteins in a cell lysate with biotin. The presence of biotin coupled to the target proteins allows for a secondary separation step in which antibodies are washed away from the reversibly biotinylated target proteins by binding them to an Avidin-coupled matrix. The captured target proteins are released from the Avidin matrix by reversing the Biotin-CDM link, thus releasing a pool of target proteins ready for further proteomic analysis compatible with 2D-electrophoresis. Here, we describe the synthesis and characterization of Biotin-CDM. We also demonstrate Biotin-CDM's use for immunoprecipitation of a known antigen, as well as its use for capturing an array of proteins targeted by the autoantibodies found in the serum a patient suffering from rheumatoid arthritis. The use of this reagent allows one to combine immunoprecipitation and 2D-Difference gel electrophoresis, overcoming the current limitations of Serological Proteome Analysis (SERPA) in discovering autoantigens. This article is part of a Special Issue entitled: Medical Proteomics.
25481649 Targeting the Fas/FasL system in Rheumatoid Arthritis therapy: Promising or risky? 2015 Oct Rheumatoid Arthritis (RA) is a chronic inflammatory disease affecting synovial joints. Tumor necrosis factor (TNF) α is a key component of RA pathogenesis and blocking this cytokine is the most common strategy to treat the disease. Though TNFα blockers are very efficient, one third of the RA patients are unresponsive or present side effects. Therefore, the development of novel therapeutic approaches is required. RA pathogenesis is characterized by the hyperplasia of the synovium, closely associated to the pseudo-tumoral expansion of fibroblast-like synoviocytes (FLS), which invade and destroy the joint structure. Hence, depletion of RA FLS has been proposed as an alternative therapeutic strategy. The TNF family member Fas ligand (FasL) was reported to trigger apoptosis in FLS of arthritic joints by binding to its receptor Fas and therefore suggested as a promising candidate for targeting the hyperplastic synovial tissue. However, this cytokine is pleiotropic and recent data from the literature indicate that Fas activation might have a disease-promoting role in RA by promoting cell proliferation. Therefore, a FasL-based therapy for RA requires careful evaluation before being applied. In this review we aim to overview what is known about the apoptotic and non-apoptotic effects of Fas/FasL system and discuss its relevance in RA.
25544022 Finding benefit in stressful uncertain circumstances: relations to social support and stig 2015 Living with a chronic illness can be challenging, but the ability to derive benefits and grow from this experience may enhance well-being. However, the possibility of obtaining such benefits may be dependent on the levels of stigmatization and lack of social support experienced by an individual as a result of the illness. Chronic fatigue syndrome (CFS) and fibromyalgia are chronic conditions that remain largely unexplained and those with these conditions must often contend with stigma and skepticism from others. Individuals with CFS/fibromyalgia often display stress-related biological alterations and the experience of stressful life events has been associated with illness development. The present study demonstrated that women with CFS/fibromyalgia (n = 40) as well as community participants who were depressed/anxious (n = 37), reported higher stigma levels than healthy women (n = 33). Moreover, women with CFS/fibromyalgia and those with depression/anxiety also reported greater levels of stigma than women with a chronic yet more widely accepted condition (n = 35; rheumatoid arthritis, osteoarthritis and multiple sclerosis). Secrecy related to stigma among those with CFS/fibromyalgia declined with increased social support, but this was not apparent among those with other chronic conditions. In addition, posttraumatic growth was lower among women with CFS/fibromyalgia compared to those with other chronic conditions. Qualitative analysis examining both negative impacts and positive changes stemming from illness experience revealed many similarities between women with CFS/fibromyalgia and those with other chronic conditions, including elevated appreciation for life, personal growth and compassion for others. However, women with CFS/fibromyalgia tended to report less positive change regarding interpersonal relationships compared to women with other chronic conditions. In general, unexplained illnesses were also accompanied by stigmatization which might ultimately contribute to women's lower ability to derive positive growth from their illness experience.
27746381 Differential capacity of therapeutic drugs to induce Rods/Rings structures in vitro and in 2016 Dec Some HCV patients using ribavirin and interferon alpha (IFN-α) develop anti-rods and rings (RR) autoantibodies, the main target of which is inosine monophosphate dehydrogenase (IMPDH), the rate-determining enzyme in de novo GTP biosynthesis. In vitro inhibition of IMPDH by ribavirin induces RR formation. Here we investigate whether other commonly used drugs that interfere with GTP biosynthesis can induce RR structures in vitro and vivo and elicit generation of autoantibodies. HEp-2 cells treated for 24h with ribavirin, mycophenolic acid (MPA), azathioprine, methotrexate or acyclovir were positive for RR structures. However, adefovir, entecavir, tenofovir and lamivudine did not induce RR structures in these cells. Structures induced by ribavirin in HEp-2 cells are stable after 24h drug-washout, while structures induced by other drugs are relatively labile, disappearing within 2h. Looking at patients treated with these drugs, HCV patients treated with ribavirin (n=17) showed higher average percentage of RR-positive peripheral mononuclear cells than autoimmune patients treated with RR-inducing immunosuppressant drugs (n=21). Serum from 173 autoimmune patients who had been treated with MPA, azathioprine or methotrexate was tested for presence of anti-RR autoantibodies, and only one sample was found to be positive. Conversely, of 48 anti-RR autoantibody positive samples identified at Fleury Laboratories over 30months, 94% were from HCV patients treated with ribavirin plus IFN-α. These data indicate that RR structures can be induced by a variety of drugs in vitro and in vivo, but anti-RR autoantibody production is mostly restricted to HCV patients under ribavirin+IFN-α treatment.
24344811 Therapeutic effects of hybrid liposomes without drugs for rheumatoid arthritis. 2015 Hybrid liposomes (HLs) can be prepared by simply sonicating a mixture of vesicular and micellar molecules in buffer solutions. This study aims to demonstrate inhibitory effects of HLs on the growth of fibroblast-like synoviocytes along with apoptosis and therapeutic effects of HLs in a mouse model with rheumatoid arthritis (RA). HLs composed of 95 mol% L-α-dimyristoylphosphatidylcholine (DMPC) and 5 mol% polyoxyethylene(23)dodecyl ether (C12(EO)23) were prepared by the sonication method. The inhibitory effects of HLs on the growth of human fibroblast-like synoviocytes-RA (HFLS-RA) cells in vitro and their inhibitory mechanism were examined. High inhibitory effects of HLs on the growth of HFLS-RA cells were observed. The induction of apoptosis by HLs was revealed on the basis of flow cytometric analysis. Furthermore, therapeutic effects of HLs in the mouse model with RA were examined in vivo. Our results demonstrate that HLs showed inhibitory effects on the growth of HFLS-RA cells in vitro along with apoptosis and therapeutic effects in mouse models of RA in vivo.
23907781 Assessing calibration of prognostic risk scores. 2016 Aug Current methods used to assess calibration are limited, particularly in the assessment of prognostic models. Methods for testing and visualizing calibration (e.g. the Hosmer-Lemeshow test and calibration slope) have been well thought out in the binary regression setting. However, extension of these methods to Cox models is less well known and could be improved. We describe a model-based framework for the assessment of calibration in the binary setting that provides natural extensions to the survival data setting. We show that Poisson regression models can be used to easily assess calibration in prognostic models. In addition, we show that a calibration test suggested for use in survival data has poor performance. Finally, we apply these methods to the problem of external validation of a risk score developed for the general population when assessed in a special patient population (i.e. patients with particular comorbidities, such as rheumatoid arthritis).
24928341 The impact of inflammatory rheumatic diseases on the presentation, severity, and outcome o 2016 Jan Patients with inflammatory rheumatic diseases (IRD) have a high burden of cardiovascular disease (CVD), leading to increased mortality and morbidity. However, it is not clear whether increased CVD mortality in IRD is due to a higher incidence or worse outcome of cardiovascular events (higher case fatality). In this observational case-control study, we assessed the outcome of acute coronary syndrome (ACS) in patients with IRDs compared to matched controls without IRD, using data from the Acute Coronary Syndrome Israeli Survey (ACSIS), a large, national, real-life registry detailing the extent, severity, and outcome of ACS. Of 2,193 subjects enrolled to the ACSIS, 20 (nine men) were identified with IRD, including 11 patients with rheumatoid arthritis, five patients with systemic lupus erythematosus (SLE), three patients with ankylosing spondylitis (AS), and one patient with psoriatic arthritis (PsA). The study patients were compared to 120 matched control patients (adjusted for age and risk factors for CVD) without IRD. Compared to controls, IRD patients had similar clinical presentation and similar type of ACS and received identical initial treatment at the ER. The two groups had comparable rates of complications including major adverse cardiovascular events (death, recurrent myocardial infarction, stroke, major bleeding, and definite stent thrombosis) (10 vs. 11.7% in the study and control group, respectively, p > 0.05), re-hospitalization (20 vs. 21.1%, respectively, p > 0.05), and severe congestive heart failure (7.7 vs. 6.9%, respectively, p > 0.05) within 30 days. The outcome and prognosis of ACS in patients with IRD is not worse than that of control, supporting the higher prevalence of CVD in this population as the cause for their excess mortality.
24720551 Efficacy and safety of mavrilimumab in Japanese subjects with rheumatoid arthritis: findin 2015 Jan OBJECTIVE: A phase IIa study investigated efficacy and safety/tolerability of ascending doses of mavrilimumab (anti-granulocyte-macrophage colony-stimulating factor receptor [GM-CSFR]α monoclonal antibody) in adult subjects with moderate to severe rheumatoid arthritis from Japan and Europe. Findings from the Japanese population are presented. METHODS: Fifty-one subjects received mavrilimumab (10-100 mg) or placebo subcutaneously every other week for 12 weeks, followed by a 12-week follow-up period. The primary endpoint was the proportion of subjects achieving a Disease Activity Score using 28 joints (DAS28)-C-reactive protein (CRP) response (decrease > 1.2 from baseline). Secondary endpoints included DAS28-CRP remission, Health Assessment Questionnaire Disability Index (HAQ-DI) and American College of Rheumatology (ACR) response. RESULTS: By Week 12, more mavrilimumab- versus placebo-treated subjects achieved a DAS28-CRP response (50.0% vs. 23.5%, p = 0.081); a significant response was seen in the 30 mg and 100 mg dose groups (both 75.0% vs. 23.5%, p = 0.028). The 100 mg group also demonstrated statistically significant HAQ-DI and ACR20 responses at Week 12. Results were generally consistent between Japanese and European populations. Overall, adverse events (AEs) were mild to moderate in intensity with one serious AE of pneumonia, considered possibly treatment-related. CONCLUSIONS: A rapid and clinically meaningful response was seen in subjects treated with GM-CSFRα blockade with mavrilimumab, supporting further investigation of mavrilimumab for the treatment of RA in Japanese subjects.
27210739 Peroxynitrite-induced structural perturbations in human IgG: A physicochemical study. 2016 Aug 1 IgG is an important defence protein. To exhibit optimum function the molecule must maintain its native structure. Peroxynitrite is a potent oxidizing and nitrating agent produced in vivo under pathophysiological conditions. It can oxidize and/or nitrate various amino acids causing changes in the structure and function of proteins. Such proteins may be involved in the pathogenesis of many inflammatory diseases, including rheumatoid arthritis. In the present work, peroxynitrite-induced structural changes in IgG have been studied by UV-visible, fluorescence, CD, FT-IR, DLS spectroscopy and DSC as well as by SDS-PAGE. Peroxynitrite-modified IgG exhibited hyperchromicity at 280 nm, quenching of tryptophan fluorescence, increase in ANS fluorescence, loss of β-sheet, shift in the positions of amide I and amide II bands, appearance of new peak in FT-IR, attachment of nitro residues and increase in melting temperature, compared to native IgG. Furthermore, peroxynitrite-modified IgG exhibited an additional peak at 420 nm, quenching in tyrosine fluorescence and enhancement in dityrosine fluorescence compared to native IgG. Generation of nitrotyrosine, dityrosine and nitrotryptophan was also observed in peroxynitrite-modified IgG. Gross structural changes in IgG caused by peroxynitrite and observed in vitro may favour autoantibodies induction in vivo under similar conditions.
24442884 Rituximab versus an alternative TNF inhibitor in patients with rheumatoid arthritis who fa 2015 Jun OBJECTIVES: To compare the effectiveness of rituximab versus an alternative tumour necrosis factor (TNF) inhibitor (TNFi) in patients with rheumatoid arthritis (RA) with an inadequate response to one previous TNFi. METHODS: SWITCH-RA was a prospective, global, observational, real-life study. Patients non-responsive or intolerant to a single TNFi were enrolled ≤4 weeks after starting rituximab or a second TNFi. Primary end point: change in Disease Activity Score in 28 joints excluding patient's global health component (DAS28-3)-erythrocyte sedimentation rate (ESR) over 6 months. RESULTS: 604 patients received rituximab, and 507 an alternative TNFi as second biological therapy. Reasons for discontinuing the first TNFi were inefficacy (n=827), intolerance (n=263) and other (n=21). A total of 728 patients were available for primary end point analysis (rituximab n=405; TNFi n=323). Baseline mean (SD) DAS28-3-ESR was higher in the rituximab than the TNFi group: 5.2 (1.2) vs 4.8 (1.3); p<0.0001. Least squares mean (SE) change in DAS28-3-ESR at 6 months was significantly greater in rituximab than TNFi patients: -1.5 (0.2) vs -1.1 (0.2); p=0.007. The difference remained significant among patients discontinuing the initial TNFi because of inefficacy (-1.7 vs -1.3; p=0.017) but not intolerance (-0.7 vs -0.7; p=0.894). Seropositive patients showed significantly greater improvements in DAS28-3-ESR with rituximab than with TNFi (-1.6 (0.3) vs -1.2 (0.3); p=0.011), particularly those switching because of inefficacy (-1.9 (0.3) vs -1.5 (0.4); p=0.021). The overall incidence of adverse events was similar between the rituximab and TNFi groups. CONCLUSIONS: These real-life data indicate that, after discontinuation of an initial TNFi, switching to rituximab is associated with significantly improved clinical effectiveness compared with switching to a second TNFi. This difference was particularly evident in seropositive patients and in those switched because of inefficacy.
27577235 Recent Progress in JAK Inhibitors for the Treatment of Rheumatoid Arthritis. 2016 Oct Rheumatoid arthritis (RA) is a systemic autoimmune disease characterized by synovial inflammation and joint destruction. Considerable advance in the treatment of RA has been made following the advent of biological disease-modifying anti-rheumatic drugs (DMARDs). However, these biologics require intravenous or subcutaneous injection and some patients fail to respond to biological DMARDs or lose their primary response. Various cytokines and cell surface molecules bind to receptors on the cell surface, resulting in the activation of various cell signaling pathways, including phosphorylation of kinase proteins. Among these kinases, the non-receptor tyrosine kinase family Janus kinase (JAK) plays a pivotal role in the pathological processes of RA. Several JAK inhibitors have been developed as new therapies for patients with RA. These are oral synthetic DMARDs that inhibit JAK1, 2, and 3. One JAK inhibitor, tofacitinib, has already been approved in many countries. Results of phase III clinical trials using a JAK1/2 inhibitor, baricitinib, have shown feasible efficacy and tolerable safety. Both drugs are effective in patients who showed inadequate response to biological DMARDs as well as synthetic DMARDs. In addition, clinical phase III trials using filgotinib and ABT-494, specific JAK1 inhibitors, are currently underway. JAK inhibitors are novel therapies for RA, but further studies are needed to determine their risk-benefit ratio and selection of the most appropriate patients for such therapy.
26655743 MDM2 promotes rheumatoid arthritis via activation of MAPK and NF-κB. 2016 Jan Murine double minute-2 (MDM2) has pleiotropic roles in immune activation and regulation. However, the role of MDM2 in rheumatoid arthritis (RA) remains unknown. We undertook this study to investigate the role of MDM2 in rheumatoid arthritis (RA). Fibroblast-like synoviocytes (FLS) were isolated from 25 patients with active RA and 25 patients with osteoarthritis (OA). FLS were stimulated in the presence or absence of IL-1β in vitro. Mice with collagen-induced arthritis (CIA) were treated with Nutlin-3a (100mg/kg) or vehicle twice daily for 2weeks. MDM2 expression was determined by Western blot. MDM2 was down-regulated by specific gene silencing. The concentrations of pro-inflammatory cytokines and matrix metalloproteinases (MMPs) were analyzed using enzyme-linked immunosorbent assay (ELISA). The pathways of mitogen-activated protein kinase (MAPK) and nuclear factor-kappa B (NF-κB) were investigated by Western blot. Arthritis scoring and histological analysis were conducted. MDM2 expression was significantly higher in RA-FLS than in OA-FLS. MDM2 protein expression was positively correlated with disease activity of RA. MDM2 promoted the production of TNF-α, IL-6, MMP1 and MMP13 through MAPK and NF-κB pathways in RA-FLS. Nutlin-3a treatment decreased the arthritis severity and joint damage in CIA. Nutlin-3a also inhibited the activation of MAPK and NF-κB in arthritic joints. In conclusion, MDM2 inhibition exhibits anti-inflammatory activity and MDM2 might be a new therapeutic target for RA.
26359027 [The distinctive characteristics of ultrasonic imaging of enthesitis in spondyloarthritis 2015 Jul OBJECTIVE: To explore the distinctive ultrasonographic characters of enthesitis in patients with spondyloarthritis (SpA) and evaluate the diagnostic value of ultrasonography in SpA by comparing ultrasonography of enthesis in the lower limbs of patients with SpA, rheumatoid arthritis (RA) and osteoarthritis (OA). METHODS: Entheses in the lower limbs (quadriceps tendon, proximal patellar ligament, distal patellar ligament, achilles tendon and plantar aponeurosis) were detected in SpA, RA, OA patients and health controls by ultrasonographic examination. RESULTS: A total of 46 SpA, 23 RA and 12 OA patients were enrolled in this study, with 26 SpA and 7 RA patients complaining of heel pain (P<0.05). There were 126 enthesal sites (126/460, 27.2%) were detected abnormal in SpA group, compared with 54 of 230 (23.5%) sites in RA group and 27 of 120 (22.5%) sites in OA group (P>0.05). Sixty five (70.7%) sites of the distal patellar ligaments were abnormal in SpA group, while that were 19 (41.3%) in RA group (P<0.05) and 13 (54.2%) in OA group. Twenty six sites of tendon thickness and 22 sites of bone erosion in the distal patellar ligaments were found in SpA group, while only one site of each in RA group (P<0.05) and 4 sites of tendon thickness in OA group (P<0.05) were found.Tendon thickness, bursal synovitis and bone erosion coexisting in one distal patellar ligament indicated SpA, the sensitivity, specificity and the area under the curve (AUC) of which were 70.7%, 65.5% and 0.740, respectively. CONCLUSION: Tendon thickness and bone erosion of entheses were more likely the distinctive ultrasonographic characters of enthesitis in SpA patients. Tendon thickness, bursal synovitis and bone erosion in the distal patellar ligament could be an ideal tool for SpA diagnosis.
27321947 Transethnic Genetic-Correlation Estimates from Summary Statistics. 2016 Jul 7 The increasing number of genetic association studies conducted in multiple populations provides an unprecedented opportunity to study how the genetic architecture of complex phenotypes varies between populations, a problem important for both medical and population genetics. Here, we have developed a method for estimating the transethnic genetic correlation: the correlation of causal-variant effect sizes at SNPs common in populations. This methods takes advantage of the entire spectrum of SNP associations and uses only summary-level data from genome-wide association studies. This avoids the computational costs and privacy concerns associated with genotype-level information while remaining scalable to hundreds of thousands of individuals and millions of SNPs. We applied our method to data on gene expression, rheumatoid arthritis, and type 2 diabetes and overwhelmingly found that the genetic correlation was significantly less than 1. Our method is implemented in a Python package called Popcorn.
27254630 [Immune system and rheumatic diseases in the elderly]. 2016 Jun Impairments of the immune system play an important role in all immun-mediated rheumatic diseases. Recently, the following news were reported: · Early aging of the immune system with thymus insufficiency has now been reported for both patients with rheumatoid arthritis and axial spondyloarthritis, without prethymic lack of progenitors at least in rheumatoid arthritis.. · For giant cell arteritis, the most frequent vasculitis in the elderly, an increased expression of IL-17A in temporal artery biopsies coincides with good prognosis and reponse to glucocorticoids.. · Concerning immunosenescence in systemic lupus erythematosus, BAFF appears to have an important role for relapses after B-cell depletion.. For the future it can be anticipated that the use of unified classification criteria for rheumatic diseases (as with the new 2012 EULAR / ACR classification criteria for polymyalgia rheumatica) will ensure better comparability of immunological studies also in the elderly.
27530379 Comparative assessment of clinical response in patients with rheumatoid arthritis between 2016 Dec AIMS: To evaluate potential differences between PF-05280586 and rituximab sourced from the European Union (rituximab-EU) and USA (rituximab-US) in clinical response (Disease Activity Score in 28 Joints [DAS28] and American College of Rheumatology [ACR] criteria), as part of the overall biosimilarity assessment of PF-05280586. METHODS: A randomised, double-blind, pharmacokinetic similarity trial was conducted in patients with active rheumatoid arthritis refractory to anti-tumour necrosis factor therapy on a background of methotrexate. Patients were treated with 1000 mg of PF-05280586, rituximab-EU or rituximab-US on days 1 and 15 and followed over 24 weeks for pharmacokinetic, clinical response and safety assessments. Key secondary end points were the areas under effect curves for DAS28 and ACR responses. Mean differences in areas under effect curves were compared against respective reference ranges established by observed rituximab-EU and rituximab-US responses using longitudinal nonlinear mixed effects models. RESULTS: The analysis included 214 patients. Demographics were similar across groups with exceptions in some baseline disease characteristics. Baseline imbalances and group-to-group variation were accounted for by covariate effects in each model. Predictions from the DAS28 and ACR models tracked the central tendency and distribution of observations well. No point estimates of mean differences were outside the reference range for DAS28 or ACR scores. The probabilities that the predicted differences between PF-05280586 vs. rituximab-EU or rituximab-US lie outside the reference ranges were low. CONCLUSIONS: No clinically meaningful differences were detected in DAS28 or ACR response between PF-05280586 and rituximab-EU or rituximab-US as the differences were within the pre-specified reference ranges. TRIAL REGISTRATION NUMBER: NCT01526057.
27742015 Imaging of Inflammatory Arthritis in Adults: Status and Perspectives on the Use of Radiogr 2016 Nov The term inflammatory arthritis encompasses a variety of conditions featuring synovial inflammation as a defining characteristic, with resultant local tissue damage occurring over time. These arthritides often share overlapping clinical and imaging characteristics, although the pattern of joint involvement, specific appearance of pathologic changes, and associated findings often allow imaging-based differentiation or individual arthritides.
26747844 How do general practitioners identify inflammatory arthritis? A cohort analysis of Dutch g 2016 May OBJECTIVE: To examine the symptoms, signs and additional investigations that general practitioners (GPs) used in the process of diagnosing recent-onset inflammatory arthritis. Here, we assumed that the recorded information was crucial in the diagnostic process of arthritis. METHODS: A database including electronic medical records of 16 Dutch general practices with 44,350 patients was studied. Patients with an episode of RA and allied conditions according to the International Classification of Primary Care-1 code L88 (here summarized as inflammatory arthritis) in the period 2009-2013 were selected. Frequencies of symptoms, signs and performed additional investigations were evaluated and compared between referred and non-referred patients. RESULTS: A total of 126 patients were diagnosed with inflammatory arthritis. Information on symptom duration, symptom location, swelling, loss of function, redness and warmth were recorded in, respectively, 64, 90, 80, 52, 48 and 41% of patients. Information on morning stiffness, family history or the squeeze-test was provided in 20, 18 and 17% of patients. Symmetry, inflammatory type arthralgia and fist closure were not recorded. Acute phase reactants and auto-antibody tests were performed in 40-46% and 8-11%, respectively. Eighty-four patients (67%) were referred to secondary care. Symptoms located in the foot, morning stiffness, family history, myalgia, absence of redness and elevated acute phase reactants were associated with referral (all P < 0.05). CONCLUSION: GPs mainly used classical signs of inflammation to diagnose inflammatory arthritis. Other items that are regularly assessed in secondary care (morning stiffness, squeeze-test, family history) were infrequently recorded by GPs.
25825024 Glycosylation of immunoglobulin G determines osteoclast differentiation and bone loss. 2015 Mar 31 Immunglobulin G (IgG) sialylation represents a key checkpoint that determines the engagement of pro- or anti-inflammatory Fcγ receptors (FcγR) and the direction of the immune response. Whether IgG sialylation influences osteoclast differentiation and subsequently bone architecture has not been determined yet, but may represent an important link between immune activation and bone loss. Here we demonstrate that desialylated, but not sialylated, immune complexes enhance osteoclastogenesis in vitro and in vivo. Furthermore, we find that the Fc sialylation state of random IgG and specific IgG autoantibodies determines bone architecture in patients with rheumatoid arthritis. In accordance with these findings, mice treated with the sialic acid precursor N-acetylmannosamine (ManNAc), which results in increased IgG sialylation, are less susceptible to inflammatory bone loss. Taken together, our findings provide a novel mechanism by which immune responses influence the human skeleton and an innovative treatment approach to inhibit immune-mediated bone loss.
25277704 Detection of Hepatitis B Virus Large Surface Protein Using a Time-Resolved Immunofluoromet 2015 Nov BACKGROUND: To establish a novel method based on time-resolved immunofluorometric assay (TR-IFMA) with higher sensitivity and a broader detection range for detecting serum hepatitis B virus large surface protein (L protein). METHODS: The precision, sensitivity, specificity, coefficient of recovery, and stability of the assay were evaluated and comparison with the classical enzyme-linked immunosorbent assay (ELISA) was also executed. RESULTS: The precision, specificity, and sensitivity of the TR-IFMA were clearly better than ELISA. Particularly, the sensitivity was 0.1 ng/ml; moreover, the specificity was 100%, 96%, 92.5%, 96.9%, 97.8%, and 100% in the sera of healthy blood donors, systemic lupus erythematosus (SLE) patients, rheumatoid arthritis (RA) patients, hepatitis C virus (HCV) patients, cytomegalovirus (CMV) infection patients, and pregnant patients, respectively. Meanwhile, we observed that the established TR-IFMA kit has a wider acceptable linear range of 0.63-10,367 ng/ml rather than the regular commercial ELISA kit having range of only 10.12-1095.9 ng/ml. Subsequently, correlation coefficient between the TR-IFMA and ELISA was 0.8009. The intra- and interassay precision rates were less than 5% for three different concentrations. The average recovery rate for L protein was 101.17%. In sum, the established assay kit performed better in terms of stability than the commercial ELISA kit. CONCLUSION: The TR-IFMA that we developed for L protein presented a higher sensitivity and wider detecting range than regular commercial ELISA. Therefore, this TR-IFMA has promising value both in the screening of HBV and monitoring of antiviral therapy.