Aquaporin-4 autoantibodies in neuromyelitis optica spectrum disorders: comparison between tissue-based and cell-based indirect immunofluorescence assays

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Chan Koon H

2010-09-01

Full Text Available Abstract Background Neuromyelitis optica spectrum disorders (NMOSD are severe central nervous system inflammatory demyelinating disorders (CNS IDD characterized by monophasic or relapsing, longitudinally extensive transverse myelitis (LETM and/or optic neuritis (ON. A significant proportion of NMOSD patients are seropositive for aquaporin-4 (AQP4 autoantibodies. We compared the AQP4 autoantibody detection rates of tissue-based indirect immunofluorescence assay (IIFA and cell-based IIFA. Methods Serum of Chinese CNS IDD patients were assayed for AQP4 autoantibodies by tissue-based IIFA using monkey cerebellum and cell-based IIFA using transfected HEK293 cells which express human AQP4 on their cell membranes. Results In total, 128 CNS IDD patients were studied. We found that 78% of NMO patients were seropositive for AQP4 autoantibodies by cell-based IIFA versus 61% by tissue-based IFA (p = 0.250, 75% of patients having relapsing myelitis (RM with LETM were seropositive by cell-based IIFA versus 50% by tissue-based IIFA (p = 0.250, and 33% of relapsing ON patients were seropositive by cell-based IIFA versus 22% by tissue-based IIFA (p = 1.000; however the differences were not statistically significant. All patients seropositive by tissue-based IIFA were also seropositive for AQP4 autoantibodies by cell-based IIFA. Among 29 NMOSD patients seropositive for AQP4 autoantibodies by cell-based IIFA, 20 (69% were seropositive by tissue-based IIFA. The 9 patients seropositive by cell-based IIFA while seronegative by tissue-based IIFA had NMO (3, RM with LETM (3, a single attack of LETM (1, relapsing ON (1 and a single ON attack (1. Among 23 NMO or RM patients seropositive for AQP4 autoantibodies by cell-based IIFA, comparison between those seropositive (n = 17 and seronegative (n = 6 by tissue-based IIFA revealed no differences in clinical and neuroradiological characteristics between the two groups. Conclusion Cell-based IIFA is slightly more sensitive

Functional diagnostics for thyrotropin hormone receptor autoantibodies: bioassays prevail over binding assays.

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Lytton, Simon David; Schluter, Anke; Banga, Paul J

2018-06-01

Autoantibodies to the thyrotropin hormone receptor (TSH-R) are directly responsible for the hyperthyroidism in Graves' disease and mediate orbital manifestations in Graves' orbitopathy (otherwise known as thyroid eye disease). These autoantibodies are heterogeneous in their function and collectively referred to as TRAbs. Measurement of TRAbs is clinically important for diagnosis of a variety of conditions and different commercial assays with high sensitivity and specificity are available for diagnostic purposes. This review provides overwhelming evidence that the TRAbs detected in binding assays by mainly the automated electrochemical luminescence immunoassays (ECLIA) do not distinguish TRAbs that stimulate the TSH-R (called TSIs or TSAbs) and TRAbs that just inhibit the binding of TSH without stimulating the TSH-R (called TBAbs). However, TSAbs and TBAbs have divergent pathogenic roles, and depending which fraction predominates cause different clinical symptoms and engender different therapeutic regimen. Therefore, diagnostic distinction of TSAbs and TBAbs is of paramount clinical importance. To date, only bioassays such as the Mc4 TSH-R bioassay (Thyretain TM , Quidel) and the Bridge assay (Immulite 2000, Siemens) can measure TSAbs, with only the former being able to distinguish between TSAbs and TBAbs. On this note, it is strongly recommended to only use the term TSI or TSAb when reporting the results of bioassays, whereas the results of automated TRAb binding assays should be reported as TRAbs (of undetermined functional significance). This review aims to present a technical and analytical account of leading commercial diagnostic methods of anti-TSH-R antibodies, a metaanalysis of their clinical performance and a perspective for the use of cell based TSH-R bioassays in the clinical diagnostics of Graves' disease.

Insulin-like growth factors: assay methods and their implications

International Nuclear Information System (INIS)

Guyda, H.J.; Posner, B.I.; Schiffrin, A.; Rappaport, R.; Postel-Vinay, M.C.; Corvol, M.T.

1981-01-01

The insulin-like growth factors (IGF's) are small molecular weight peptides (6-10 x 10 3 daltons) that circulate in blood plasma almost entirely bound to macromolecular carrier proteins. The growth-promoting and insulin-like activities of IGF's can be explained by the observed ability of these peptides to interact with the IGF receptor on the one hand and with the insulin receptor on the other. These observations have led to the establishment of radioreceptor assays (RRA's), competitive protein binding assays (CPBA's), and more recently radioimmunoassays (RIA's) for the IGF's that have different specificities. Because of their ease of performance and sensitivity, the radioligand assays have largely supplanted the biological assays originally utilized to identify and characterize these anabolic peptides. In this report the authors' studies are summarised which utilize a slightly acidic IGF which has been purified on the basis of its insulin-like activity in an insulin RRA and which was termed ILAs. They refer to purified insulin-like peptides that have the properties of a somatomedin by the generic term insulin-like growth factor (IGF). Somatomedin (SM) activity will be utilized to connote that activity in plasma or serum determined by bioassay. The competitive dose-response curves for IGF peptides in the insulin RRA as well as those in the ILAs RRA are presented. A combination of bioassays, RRA and RIA were employed to assess somatomedin activity and IGF peptide levels in a number of clinical circumstances. The correlations are discussed. (Auth.)

Development of a Rapid Insulin Assay by Homogenous Time-Resolved Fluorescence.

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Zachary J Farino

Full Text Available Direct measurement of insulin is critical for basic and clinical studies of insulin secretion. However, current methods are expensive and time-consuming. We developed an insulin assay based on homogenous time-resolved fluorescence that is significantly more rapid and cost-effective than current commonly used approaches. This assay was applied effectively to an insulin secreting cell line, INS-1E cells, as well as pancreatic islets, allowing us to validate the assay by elucidating mechanisms by which dopamine regulates insulin release. We found that dopamine functioned as a significant negative modulator of glucose-stimulated insulin secretion. Further, we showed that bromocriptine, a known dopamine D2/D3 receptor agonist and newly approved drug used for treatment of type II diabetes mellitus, also decreased glucose-stimulated insulin secretion in islets to levels comparable to those caused by dopamine treatment.

The implications of autoantibodies to a single islet antigen in relatives with normal glucose tolerance: development of other autoantibodies and progression to type 1 diabetes.

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Bingley, Polly J; Boulware, David C; Krischer, Jeffrey P

2016-03-01

Autoantibodies directed at single islet autoantigens are associated with lower overall risk of type 1 diabetes than multiple autoantibodies, but individuals with one autoantibody may progress to higher risk categories. We examined the characteristics of this progression in relatives followed prospectively in the TrialNet Pathway to Prevention. The study population comprised 983 relatives who were single autoantibody positive with normal baseline glucose tolerance (median age 16.2 years). Samples were screened for antibodies to GAD, insulinoma-associated antigen 2 (IA-2) and insulin, and all positive samples tested for antibodies to zinc transporter 8 and islet cell antibodies. Antibodies to at least one additional islet autoantigen appeared in 118 of 983 relatives (overall 5 year risk 22%, 95% CI [17.9, 26.1]). At baseline, antibodies to GAD alone (68%) were more frequent than antibodies to insulin (26%) or IA-2 (6%), but all were associated with a similar risk of developing additional autoantibodies. Risk was associated with younger age (p = 0.002) and HLA class II genotype, but was similar in high and intermediate genetic risk groups (p = 0.65). Relatives who became multiple autoantibody positive during the follow-up had increased risk of developing diabetes comparable with the risk in relatives with multiple autoantibodies at study entry. Progression of islet autoimmunity in single autoantibody positive relatives in late childhood/adult life is associated with a predominance of autoantibodies to GAD and a distinct HLA risk profile. This heterogeneity in type 1 diabetes autoimmunity has potentially important implications for disease prevention.

Frequency of islet cell autoantibodies (IA-2 and GAD in young Brazilian type 1 diabetes patients

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Pardini V.C.

1999-01-01

Full Text Available Type 1 diabetes, as an autoimmune disease, presents several islet cell-specific autoantibodies such as islet cell antibody (ICA, anti-insulin, anti-glutamic acid decarboxylase (GAD and the antibody (Ab against tyrosine phosphatase (PTP-like protein known as ICA-512 (IA-2. In order to determine the frequency of the anti-GAD and anti-IA-2 autoantibodies in Brazilian type 1 diabetes patients we studied 35 diabetes mellitus (DM type 1 patients with recent-onset disease (£12 months and 37 type 1 diabetes patients with long-duration diabetes (>12 months who were compared to 12 children with normal fasting glucose. Anti-GAD65 and anti-IA-2 autoantibodies were detected with commercial immunoprecipitation assays. The frequency of positive results in recent-onset DM type 1 patients was 80.0% for GADAb, 62.9% for IA-2Ab and 82.9% for GADAb and/or IA-2Ab. The long-duration type 1 diabetes subjects presented frequencies of 54.1% for GADAb and IA-2Ab, and 67.5% for GAD and/or IA-2 antibodies. The control group showed no positive cases. Anti-GAD and IA-2 assays showed a high frequency of positivity in these Brazilian type 1 diabetes patients, who presented the same prevalence as a Caucasian population.

Autoantibodies in Autoimmune Hepatitis.

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Muratori, Luigi; Deleonardi, Gaia; Lalanne, Claudine; Barbato, Erica; Tovoli, Alessandra; Libra, Alessia; Lenzi, Marco; Cassani, Fabio; Muratori, Paolo

2015-01-01

The detection of diagnostic autoantibodies such as antinuclear antibodies (ANA), anti-smooth muscle antibodies (SMA), anti-liver/kidney microsomal type 1 (anti-LKM1), anti-liver cytosol type 1 (anti-LC1) and anti-soluble liver antigen (anti-SLA) is historically associated with the diagnosis of autoimmune hepatitis. When autoimmune hepatitis is suspected, the detection of one or any combination of diagnostic autoantibodies, by indirect immunofluorescence or immuno-enzymatic techniques with recombinant antigens, is a pivotal step to reach a diagnostic score of probable or definite autoimmune hepatitis. Diagnostic autoantibodies (ANA, SMA, anti-LKM1, anti-LC1, anti-SLA) are a cornerstone in the diagnosis of autoimmune hepatitis. Other ancillary autoantibodies, associated with peculiar clinical correlations, appear to be assay-dependent and institution-specific, and validation studies are needed. © 2015 S. Karger AG, Basel.

Prevalence and predictive value of islet cell antibodies and insulin autoantibodies in women with gestational diabetes

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Damm, P; Kühl, C; Buschard, K

1994-01-01

The objective of the present study was to investigate the predictive value of islet cell antibodies (ICA) and insulin autoantibodies (IAA) for development of diabetes in women with previous gestational diabetes (GDM). Two hundred and forty-one previous diet-treated GDM patients and 57 women without...... for ICA were ICA-positive and three of these had Type 1 diabetes at follow-up, as well as three ICA-negative patients. The sensitivity, specificity, and predictive value of ICA-positivity for later development of diabetes were 50%, 99%, and 75%, respectively. None of the women was IAA-positive during...

Hyperinsulinemic hypoglycemia associated with insulin antibodies caused by exogenous insulin analog

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Chih-Ting Su

2016-11-01

Full Text Available Insulin antibodies (IA associated with exogenous insulin administration seldom caused hypoglycemia and had different characteristics from insulin autoantibodies (IAA found in insulin autoimmune syndrome (IAS, which was first described by Dr Hirata in 1970. The characteristic of IAS is the presence of insulin-binding autoantibodies and related fasting or late postprandial hypoglycemia. Here, we report a patient with type 1 diabetes mellitus under insulin glargine and insulin aspart treatment who developed recurrent spontaneous post-absorptive hyperinsulinemic hypoglycemia with the cause probably being insulin antibodies induced by exogenous injected insulin. Examinations of serial sera disclosed a high titre of insulin antibodies (33%, normal <5%, high insulin concentration (111.9 IU/mL and undetectable C-peptide when hypoglycemia occurred. An oral glucose tolerance test revealed persistent high serum levels of total insulin and undetectable C-peptide. Image studies of the pancreas were unremarkable, which excluded the diagnosis of insulinoma. The patient does not take any of the medications containing sulfhydryl compounds, which had been reported to cause IAS. After administering oral prednisolone for 3 weeks, hypoglycemic episodes markedly improved, and he was discharged smoothly.

Extrapancreatic Autoantibody Profiles in Type I Diabetes

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Burbelo, Peter D.; Lebovitz, Evan E.; Bren, Kathleen E.; Bayat, Ahmad; Paviol, Scott; Wenzlau, Janet M.; Barriga, Katherine J.; Rewers, Marian; Harlan, David M.; Iadarola, Michael J.

2012-01-01

Type I diabetes (T1D) is an autoimmune disease characterized by destruction of insulin-producing β-cells in the pancreas. Although several islet cell autoantigens are known, the breadth and spectrum of autoantibody targets has not been fully explored. Here the luciferase immunoprecipitation systems (LIPS) antibody profiling technology was used to study islet and other organ-specific autoantibody responses in parallel. Examination of an initial cohort of 93 controls and 50 T1D subjects revealed that 16% of the diabetic subjects showed anti-gastric ATPase autoantibodies which did not correlate with autoantibodies against GAD65, IA2, or IA2-β. A more detailed study of a second cohort with 18 potential autoantibody targets revealed marked heterogeneity in autoantibody responses against islet cell autoantigens including two polymorphic variants of ZnT8. A subset of T1D subjects exhibited autoantibodies against several organ-specific targets including gastric ATPase (11%), thyroid peroxidase (14%), and anti-IgA autoantibodies against tissue transglutaminase (12%). Although a few T1D subjects showed autoantibodies against a lung-associated protein KCNRG (6%) and S100-β (8%), no statistically significant autoantibodies were detected against several cytokines. Analysis of the overall autoantibody profiles using a heatmap revealed two major subgroups of approximately similar numbers, consisting of T1D subjects with and without organ-specific autoantibodies. Within the organ-specific subgroup, there was minimal overlap among anti-gastric ATPase, anti-thyroid peroxidase, and anti-transglutaminase seropositivity, and these autoantibodies did not correlate with islet cell autoantibodies. Examination of a third cohort, comprising prospectively collected longitudinal samples from high-risk individuals, revealed that anti-gastric ATPase autoantibodies were present in several individuals prior to detection of islet autoantibodies and before clinical onset of T1D. Taken together

Development of real-time reverse transcription polymerase chain reaction assays to quantify insulin-like growth factor receptor and insulin receptor expression in equine tissue

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Stephen B. Hughes

2013-08-01

Full Text Available The insulin-like growth factor system (insulin-like growth factor 1, insulin-like growth factor 2, insulin-like growth factor 1 receptor, insulin-like growth factor 2 receptor and six insulin-like growth factor-binding proteins and insulin are essential to muscle metabolism and most aspects of male and female reproduction. Insulin-like growth factor and insulin play important roles in the regulation of cell growth, differentiation and the maintenance of cell differentiation in mammals. In order to better understand the local factors that regulate equine physiology, such as muscle metabolism and reproduction (e.g., germ cell development and fertilisation, real-time reverse transcription polymerase chain reaction assays for quantification of equine insulin-like growth factor 1 receptor and insulin receptor messenger ribonucleic acid were developed. The assays were sensitive: 192 copies/µLand 891 copies/µL for insulin-like growth factor 1 receptor, messenger ribonucleic acid and insulin receptor respectively (95%limit of detection, and efficient: 1.01 for the insulin-like growth factor 1 receptor assay and 0.95 for the insulin receptor assay. The assays had a broad linear range of detection (seven logs for insulin-like growth factor 1 receptor and six logs for insulin receptor. This allowed for analysis of very small amounts of messenger ribonucleic acid. Low concentrations of both insulin-like growth factor 1 receptor and insulin receptor messenger ribonucleic acid were detected in endometrium, lung and spleen samples, whilst high concentrations were detected in heart, muscle and kidney samples, this was most likely due to the high level of glucose metabolism and glucose utilisation by these tissues. The assays developed for insulin-like growth factor 1 receptor and insulin receptor messenger ribonucleic acid expression have been shown to work on equine tissue and will contribute to the understanding of insulin and insulin-like growth factor 1

Comparison of clinical and laboratory characteristics in children with type 1 diabetes according to pancreatic autoantibodies

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Ji Hae Choi

2010-03-01

Full Text Available Purpose:The purpose of this study was to determine whether there is any difference in the clinical and laboratory characteristics of patients with autoantibody-positive and patients with autoantibody-negative type 1 diabetes at initial presentation. Methods:We analyzed 96 patients under 18 years of age with newly diagnosed type 1 diabetes. One or both of the pancreatic autoantibodies-glutamic acid decarboxylase autoantibodies (GADA and insulin autoantibody (IAA-were measured in all patients, and we reviewed clinical and laboratory characteristics according to the presence of these autoantibodies. Results:GADA was examined in 48 of 87 patients, and 55.2% of patients were positive. IAA was checked in 88 patients, and 39.8% were positive. Both GADA and IAA were measured in 83 patients, and 22.8% had both antibodies. The patients who had one or both autoantibodies (autoantibody-positive group were younger than those not having any autoantibody (autoantibody-negative group. The autoantibody-positive group had lower BMI, corrected sodium level, and serum effective osmolarity, compared to the autoantibody-negative group (P&lt;0.05. Similar differences were found between the GADA-positive and GADA-negative groups. However, there were no significant differences between the IAA- positive and IAA-negative groups. Conclusion:The prevalence of pancreatic autoantibodies was significantly higher in the under-6 years age group than in the other age groups. These findings suggest that measurement of autoantibodies at the initial diagnosis of diabetes is very useful for detecting immune-mediated type 1 diabetes and providing intensive insulin therapy, especially in younger children.

A high-throughput mass spectrometry assay to simultaneously measure intact insulin and C-peptide.

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Taylor, Steven W; Clarke, Nigel J; Chen, Zhaohui; McPhaul, Michael J

2016-04-01

Measurements of fasting levels of insulin and C-peptide are useful in documenting insulin resistance and may help predict development of diabetes mellitus. However, the specific insulin and C-peptide levels associated with specific degrees of insulin resistance have not been defined, owing to marked variability among immunoassays and lack of standardization. Herein, we describe a multiplexed liquid chromatography-tandem mass spectrometry (LC-MS/MS) assay for intact insulin and C-peptide. Insulin and C-peptide were enriched from patient sera using monoclonal antibodies immobilized on magnetic beads and processed on a robotic liquid handler. Eluted peptides were analyzed by LC-MS/MS. Bovine insulin and a stable isotopically-labeled (13C/15N) C-peptide were utilized as internal standards. The assay had an analytical measurement range of 3 to 320 μIU/ml (18 to 1920 pmol/l) for insulin and 0.11 to 27.2 ng/ml (36 to 9006 pmol/l) for C-peptide. Intra- and inter-day assay variation was less than 11% for both peptides. Of the 5 insulin analogs commonly prescribed to treat diabetes, only the recombinant drug insulin lispro caused significant interference for the determination of endogenous insulin. There were no observed interferences for C-peptide. We developed and validated a high-throughput, quantitative, multiplexed LC-MS/MS assay for intact insulin and C-peptide. Copyright © 2016 Elsevier B.V. All rights reserved.

Glutamic acid decarboxylase autoantibody-positivity post-partum is associated with impaired β-cell function in women with gestational diabetes mellitus.

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Lundberg, T P; Højlund, K; Snogdal, L S; Jensen, D M

2015-02-01

To investigate whether the presence of glutamic acid decarboxylase (GAD) autoantibodies post-partum in women with prior gestational diabetes mellitus was associated with changes in metabolic characteristics, including β-cell function and insulin sensitivity. During 1997-2010, 407 women with gestational diabetes mellitus were offered a 3-month post-partum follow-up including anthropometrics, serum lipid profile, HbA1c and GAD autoantibodies, as well as a 2-h oral glucose tolerance test (OGTT) with blood glucose, serum insulin and C-peptide at 0, 30 and 120 min. Indices of insulin sensitivity and insulin secretion were estimated to assess insulin secretion adjusted for insulin sensitivity, disposition index (DI). Twenty-two (5.4%) women were positive for GAD autoantibodies (GAD+ve) and the remainder (94.6%) were negative for GAD autoantibodies (GAD-ve). The two groups had similar age and prevalence of diabetes mellitus. Women who were GAD+ve had significantly higher 2-h OGTT glucose concentrations during their index-pregnancy (10.5 vs. 9.8 mmol/l, P = 0.001), higher fasting glucose (5.2 vs. 5.0 mmol/l, P = 0.02) and higher 2-h glucose (7.8 vs. 7.1 mmol/l, P = 0.05) post-partum. Fasting levels of C-peptide and insulin were lower in GAD+ve women compared with GAD-ve women (520 vs. 761 pmol/l, P = 0.02 and 33 vs. 53 pmol/l, P = 0.05) Indices of insulin sensitivity were similar in GAD+ve and GAD-ve women, whereas all estimates of DI were significantly reduced in GAD+ve women. GAD+ve women had higher glucose levels and impaired insulin secretion adjusted for insulin sensitivity (DI) compared with GAD-ve women. The combination of OGTT and GAD autoantibodies post-partum identify women with impaired β-cell function. These women should be followed with special focus on development of Type 1 diabetes. © 2014 The Authors. Diabetic Medicine © 2014 Diabetes UK.

Non-obese adult onset diabetes with oral hypoglycemic agent failure: islet cell autoantibodies or reversible beta cell refractoriness?

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J.R. Sá

2003-10-01

Full Text Available Pancreatic ß cell function and insulin sensitivity, analyzed by the homeostasis model assessment, before and after 24 weeks of insulin therapy were studied and correlated with the presence of autoantibodies against ß cells (islet cell and anti-glutamic acid decarboxylase antibodies, in a group of 18 Brazilian lean adult non-insulin-dependent diabetes mellitus (NIDDM patients with oral hypoglycemic agent failure (OHAF. Median fasting plasma glucose before and after insulin treatment was 19.1 and 8.5 mmol/l, respectively (P < 0.001; median HbA1c was 11.7% before vs 7.2% after insulin treatment (P < 0.001. Forty-four percent of the patients were positive (Ab+ to at least one autoantibody. Fasting C-peptide levels were lower in Ab+ than Ab- patients, both before (Ab+: 0.16 ± 0.09 vs Ab-: 0.41 ± 0.35 nmol/l, P < 0.003 and after insulin treatment (Ab+: 0.22 ± 0.13 vs Ab-: 0.44 ± 0.24 nmol/l, P < 0.03. Improvement of Hß was seen in Ab- (median before: 7.3 vs after insulin therapy: 33.4%, P = 0.003 but not in Ab+ patients (median before: 6.6 vs after insulin therapy: 20.9%. These results show that the OHAF observed in the 18 NIDDM patients studied was due mainly to two major causes: autoantibodies and ß cell desensitization. Autoantibodies against ß cells could account for 44% of OHAF, but Ab- patients may still present ß cell function recovery, mainly after a period of ß cell rest with insulin therapy. However, the effects of ß cell function recovery on the restoration of the response to oral hypoglycemic agents need to be determined.

Insulin autoantibodies: evidence of autoimmune disease among a group of Puerto Rican children with newly diagnosed type 1 diabetes mellitus.

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González de Pijem, L; Nieves-Rivera, F

2001-06-01

Type 1 diabetes is a chronic disease caused by a cell-specific destruction of the insulin producing cells of the pancreas. Although Puerto Rico has the highest incidence of type 1 diabetes among Latin American countries, there is scanty data on the presence of antibodies against insulin producing cells. To this end, 20 children (8 males, 12 females), ages 1-15 years, admitted to the University Pediatric Hospital with type 1 diabetes de novo between November 2000 and April 2001 were prospectively studied to determine the presence of serum antibodies against Islet cells (ICA), glutamic acid decarboxylase (GAD-65) and insulin autoantibodies (IAA). IAA was found to be present in 45% of the subjects with 85% of positive rate in subjects under age 5. GAD-65 was present in 66% and ICA was present in 23% of the subjects. We found evidence of autoimmunity against islet cell surface and intracellular components among a cohort of Puerto Rican children with newly diagnosed type 1 diabetes. These findings compared favorably with reports from other ethnicities.

Novel Association Between Immune-Mediated Susceptibility Loci and Persistent Autoantibody Positivity in Type 1 Diabetes

DEFF Research Database (Denmark)

Brorsson, Caroline A; Onengut, Suna; Chen, Wei-Min

2015-01-01

Islet autoantibodies detected at disease onset in patients with type 1 diabetes are signs of an autoimmune destruction of the insulin-producing β-cells. To further investigate the genetic determinants of autoantibody positivity, we performed dense immune-focused genotyping on the Immunochip array...... and tested for association with seven disease-specific autoantibodies in a large cross-sectional cohort of 6,160 type 1 diabetes-affected siblings. The genetic association with positivity for GAD autoantibodies (GADAs), IA2 antigen (IA-2A), zinc transporter 8, thyroid peroxidase, gastric parietal cells (PCAs...... and constitute candidates for early screening. Major susceptibility loci for islet autoantibodies are separate from type 1 diabetes risk, which may have consequences for intervention strategies to reduce autoimmunity....

GPIHBP1 autoantibodies in a patient with unexplained chylomicronemia

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Hu, Xuchen; Dallinga-Thie, Geesje M.; Hovingh, G. Kees

2017-01-01

into the frequency of the GPIHBP1 autoantibody syndrome in patients with unexplained chylomicronemia. Methods We used enzyme-linked immunosorbent assays to screen for GPIHBP1 autoantibodies in 33 patients with unexplained chylomicronemia and then used Western blots and immunocytochemistry studies to characterize....... The patient had no history of autoimmune disease, but his plasma was positive for antinuclear antibodies. Conclusions One of 33 patients with unexplained chylomicronemia had the GPIHBP1 autoantibody syndrome. Additional studies in large lipid clinics will be helpful for better defining the frequency...

A BRET assay for monitoring insulin receptor interactions and ligand pharmacology

DEFF Research Database (Denmark)

Kulahin, Nikolaj; Sanni, Samra J; Slaaby, Rita

2012-01-01

The insulin receptor (IR) belongs to the receptor tyrosine kinase super family and plays an important role in glucose homeostasis. The receptor interacts with several large docking proteins that mediate signaling from the receptor, including the insulin receptor substrate (IRS) family and Src...... for monitoring the interactions between the IR and its substrates. Furthermore, the insulin analogue X10 was characterized in the BRET2 assay and was found to be 10 times more potent with respect to IRS1, IRS4 and Shc recruitment compared to human insulin. This study demonstrates that the BRET2 technique can...

14-3-3η Autoantibodies: Diagnostic Use in Early Rheumatoid Arthritis

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Maksymowych, Walter P.; Boire, Gilles; van Schaardenburg, Dirkjan; Wichuk, Stephanie; Turk, Samina; Boers, Maarten; Siminovitch, Katherine A.; Bykerk, Vivian; Keystone, Ed; Tak, Paul Peter; van Kuijk, Arno W.; Landewé, Robert; van der Heijde, Desiree; Murphy, Mairead; Marotta, Anthony

2015-01-01

To describe the expression and diagnostic use of 14-3-3η autoantibodies in early rheumatoid arthritis (RA). 14-3-3η autoantibody levels were measured using an electrochemiluminescent multiplexed assay in 500 subjects (114 disease-modifying antirheumatic drug-naive patients with early RA, 135 with

Novel immunoradiometric assay of thyroglobulin in serum with use of monoclonal antibodies selected for lack of cross-reactivity with autoantibodies

International Nuclear Information System (INIS)

Piechaczyk, M.; Baldet, L.; Pau, B.; Bastide, J.M.

1989-01-01

A multisite immunoradiometric assay for measurement of serum thyroglobulin (Tg), designated Magnogel-IRMA-Tg, has been developed, involving magnetic microbeads (Magnogel). This assay is based on the use of five anti-Tg monoclonal antibodies (MAbs) directed against three antigenic regions on the Tg molecule that are not recognized by anti-Tg autoantibodies (aAbs). Four of these MAbs, directed against two antigenic domains, were coupled to the magnetic beads and were used to trap the serum antigen. Another MAb, directed against the third region, was iodinated and served as the labeled second antibody. The Magnogel-IRMA-Tg technique is reproducible, rapid, and sensitive (lower detection limit, 3 micrograms/L). The assay reliably measures serum Tg in the presence of anti-Tg aAbs

Increased immune complexes of hypocretin autoantibodies in narcolepsy.

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Deloumeau, Aude; Bayard, Sophie; Coquerel, Quentin; Déchelotte, Pierre; Bole-Feysot, Christine; Carlander, Bertrand; Cochen De Cock, Valérie; Fetissov, Sergueï O; Dauvilliers, Yves

2010-10-13

Hypocretin peptides participate in the regulation of sleep-wake cycle while deficiency in hypocretin signaling and loss of hypocretin neurons are causative for narcolepsy-cataplexy. However, the mechanism responsible for alteration of the hypocretin system in narcolepsy-cataplexy and its relevance to other central hypersomnias remain unknown. Here we studied whether central hypersomnias can be associated with autoantibodies reacting with hypocretin-1 peptide present as immune complexes. Serum levels of free and dissociated (total) autoantibodies reacting with hypocretin-1 peptide were measured by enzyme-linked immunosorbent assay and analyzed with regard to clinical parameters in 82 subjects with narcolepsy-cataplexy, narcolepsy without cataplexy or idiopathic hypersomnia and were compared to 25 healthy controls. Serum levels of total but not free IgG autoantibodies against hypocretin-1 were increased in narcolepsy-cataplexy. Increased levels of complexed IgG autoantibodies against hypocretin-1 were found in all patients groups with a further increase in narcolepsy-cataplexy. Levels of total IgM hypocretin-1 autoantibodies were also elevated in all groups of patients. Increased levels of anti-idiotypic IgM autoantibodies reacting with hypocretin-1 IgG autoantibodies affinity purified from sera of subjects with narcolepsy-cataplexy were found in all three groups of patients. Disease duration correlated negatively with serum levels of hypocretin-1 IgG and IgM autoantibodies and with anti-idiotypic IgM autoantibodies. Central hypersomnias and particularly narcolepsy-cataplexy are characterized by higher serum levels of autoantibodies directed against hypocretin-1 which are present as immune complexes most likely with anti-idiotypic autoantibodies suggesting their relevance to the mechanism of sleep-wake cycle regulation.

Increased immune complexes of hypocretin autoantibodies in narcolepsy.

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Aude Deloumeau

Full Text Available BACKGROUND: Hypocretin peptides participate in the regulation of sleep-wake cycle while deficiency in hypocretin signaling and loss of hypocretin neurons are causative for narcolepsy-cataplexy. However, the mechanism responsible for alteration of the hypocretin system in narcolepsy-cataplexy and its relevance to other central hypersomnias remain unknown. Here we studied whether central hypersomnias can be associated with autoantibodies reacting with hypocretin-1 peptide present as immune complexes. METHODOLOGY: Serum levels of free and dissociated (total autoantibodies reacting with hypocretin-1 peptide were measured by enzyme-linked immunosorbent assay and analyzed with regard to clinical parameters in 82 subjects with narcolepsy-cataplexy, narcolepsy without cataplexy or idiopathic hypersomnia and were compared to 25 healthy controls. PRINCIPAL FINDINGS: Serum levels of total but not free IgG autoantibodies against hypocretin-1 were increased in narcolepsy-cataplexy. Increased levels of complexed IgG autoantibodies against hypocretin-1 were found in all patients groups with a further increase in narcolepsy-cataplexy. Levels of total IgM hypocretin-1 autoantibodies were also elevated in all groups of patients. Increased levels of anti-idiotypic IgM autoantibodies reacting with hypocretin-1 IgG autoantibodies affinity purified from sera of subjects with narcolepsy-cataplexy were found in all three groups of patients. Disease duration correlated negatively with serum levels of hypocretin-1 IgG and IgM autoantibodies and with anti-idiotypic IgM autoantibodies. CONCLUSION: Central hypersomnias and particularly narcolepsy-cataplexy are characterized by higher serum levels of autoantibodies directed against hypocretin-1 which are present as immune complexes most likely with anti-idiotypic autoantibodies suggesting their relevance to the mechanism of sleep-wake cycle regulation.

Antibody-Mediated Extreme Insulin Resistance: A Report of Three Cases.

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Kim, Han Na; Fesseha, Betiel; Anzaldi, Laura; Tsao, Allison; Galiatsatos, Panagis; Sidhaye, Aniket

2018-01-01

Type 2 diabetes mellitus is characterized by relative insulin deficiency and insulin resistance. Features suggesting severe insulin resistance include acanthosis nigricans, hyperandrogenism, weight loss, and recurrent hospital admissions for diabetic ketoacidosis. In rare circumstances, hyperglycemia persists despite administration of massive doses of insulin. In these cases, it is important to consider autoimmune etiologies for insulin resistance, such as type B insulin resistance and insulin antibody-mediated extreme insulin resistance, which carry high morbidity and mortality if untreated. Encouragingly, immunomodulatory regimens have recently been published that induce remission at high rates. We describe 3 cases of extreme insulin resistance mediated by anti-insulin receptor autoantibodies or insulin autoantibodies. All cases were effectively treated with an immunomodulatory regimen. Although cases of extreme insulin resistance are rare, it is important to be aware of autoimmune causes, recognize suggestive signs and symptoms, and pursue appropriate diagnostic evaluation. Prompt treatment with immunomodulators is key to restoring euglycemia in patients with autoimmune etiologies of insulin resistance. Copyright © 2018 Elsevier Inc. All rights reserved.

P53 autoantibodies in 1006 patients followed up for breast cancer

International Nuclear Information System (INIS)

Metcalfe, Su; Wheeler, Terence K; Picken, Sheila; Negus, Susanne; Jo Milner, A

2000-01-01

ask if the presence of autoantibodies to p53 has any association with breast cancer progression. A library of plasma samples were collected from all patients attending one general oncology clinic for postoperative follow up of breast cancer. The clinical status of each patient at the time of sampling was summarized. An average of eight plasma samples were cryopreserved for each patient over a period of 15 years. The enzyme-linked immusorbent assay (ELISA) for p53 autoantibodies was developed in-house, based on the ELISA procedure of Lubin et al [3]. Our in-house method is detailed in the full text of this article. In one assay series we compared a commercial ELISA kit for p53 autoantibodies with our in-house ELISA. A total of 20 patients' samples were tested, representing a range of positive and negative readings. Two samples scored as strongly positive with the in-house assay, but only one of these two scored positive with the commercial assay. Having established sensitivity, specificity and reproducibility of the in-house assay, we judged that this was superior to the commercial assay both in terms of sensitivity and of cost (£1 per test compared with £23 per test). The in-house assay was thus used throughout the present study. Serial plasma samples from 1006 patients with breast cancer revealed the following: (i) no correlation of p53 autoantibody status with disease status at the time of sample collection (Table 1), or with menopausal status at time of primary diagnosis of breast cancer (Table 2); (ii) 155 out of 1006 (15%) of patients were positive for p53 autoantibodies, and these patients tended to have a persistent autoantibody status throughout follow up, irrespective of disease behaviour; and (iii) where a negative autoantibody status was found at primary diagnosis of breast cancer, this negative status persisted throughout follow up, irrespective of later disease behaviour (Table 3). As a working hypothesis, we proposed that levels of autoantibodies

Superiority of radiobinding assay over ELISA for detection of IAAs in newly diagnosed type I diabetic children

International Nuclear Information System (INIS)

Levy-Marchal, C.; Bridel, M.P.; Sodoyez-Goffaux, F.; Koch, M.; Tichet, J.; Czernichow, P.; Sodoyez, J.C.

1991-01-01

Liquid- or solid-phase assays have been used for insulin autoantibody (IAA) determination, and the method of IAA measurement has not been standardized. IAAs were determined by radiobinding assay (RBA) and enzyme-linked immunosorbent assay (ELISA) in two large age-matched groups of nondiabetic and newly diagnosed insulin-dependent (type I) diabetic children. Positivity for IAA by RBA (greater than or equal to nondiabetic mean + 3SD) was 2 of 178 (1.1%) and 55 of 173 (32%) in nondiabetic and diabetic children, respectively. Prevalence of IAA by RBA was significantly higher in the youngest age-group (63% between 0-4 yr). Positivity for IAA by ELISA was 1 of 178 (0.6%) and 8 of 169 (4.7%) in nondiabetic and diabetic children, respectively. Concordance rates between both assays were 0 of 3 (0%) in control subjects and 5 of 58 (8.6%) in diabetic children. We conclude that RBA is more appropriate than ELISA for IAA detection at the onset of the disease. In addition, because available data suggest that IAAs detected by RBA only are high-affinity antibodies, it is tempting to speculate that IAAs reflect a mature immune reaction against endogenous insulin

Autoantibody Profiling in a Cohort of Pediatric and Adult Patients With Autoimmune Hepatitis.

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Villalta, Danilo; Girolami, Elia; Alessio, Maria Grazia; Sorrentino, Maria Concetta; Tampoia, Marilina; Brusca, Ignazio; Daves, Massimo; Porcelli, Brunetta; Barberio, Giuseppina; Conte, Mariaelisabetta; Pantarotto, Lisa; Bizzaro, Nicola

2016-01-01

Autoimmune hepatitis (AIH) is a rare condition characterized by the presence of autoantibodies distinctive of type 1 AIH (AIH-1) and type 2 AIH (AIH-2). The aim of this study was to evaluate the autoantibody profile in a cohort of pediatric and adult AIH patients, using both indirect immunofluorescence (IIF) and a new multiplexed line-blot assay. Sera from 63 pediatric and 53 adult AIH patients were tested for antinuclear (ANA), antismooth muscle (SMA), anti-liver kidney microsome 1 (anti-LKM1), anti-liver cytosol 1 (anti-LC1) autoantibodies using IIF methods; for anti-LKM1, anti-LC1, and soluble liver antigen/liver-pancreas (anti-SLA/LP) autoantibodies using the line-blot; for anti-F-actin autoantibodies using IIF both on VSM47 cell-line and on rat intestinal epithelial cells. AIH-1 was the most common type of AIH in the adult cohort (73.6%), while AIH-2 was the most common AIH in the pediatric cohort (61.9%). Both in adult and pediatric AIH-2 anti-LKM1 were the prevalent autoantibodies. In pediatric AIH-2 anti-LC1 autoantibodies were more frequent than in adult AIH-2 (59 vs. 28.6%), and in 35.9% of cases they were present alone. In 17 patients anti-LC1 autoantibodies were detected only with the line-blot assay. The levels of anti-LKM1 and of anti-LC1 were not different between adult and pediatric AIH, and the overall agreement between the results obtained with the two IIF methods for F-actin detection was 98.8% (CI 95%: 94.4-99.7%). The line-blot assay showed a higher sensitivity than IIF for anti-LC1 detection. Anti-LKM1 and anti-LC1 autoantibody levels are not different in adults and children. An almost perfect agreement between the two IIF methods for anti-F-actin detection has been observed. © 2014 Wiley Periodicals, Inc.

Automated microfluidic assay system for autoantibodies found in autoimmune diseases using a photoimmobilized autoantigen microarray.

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Matsudaira, Takahiro; Tsuzuki, Saki; Wada, Akira; Suwa, Akira; Kohsaka, Hitoshi; Tomida, Maiko; Ito, Yoshihiro

2008-01-01

Autoimmune diseases such as rheumatoid arthritis, multiple sclerosis, and autoimmune diabetes are characterized by the production of autoantibodies that serve as useful diagnostic markers, surrogate markers, and prognostic factors. We devised an in vitro system to detect these clinically pivotal autoantibodies using a photoimmobilized autoantigen microarray. Photoimmobilization was useful for preparing the autoantigen microarray, where autoantigens are covalently immobilized on a plate, because it does not require specific functional groups of the autoantigens and any organic material can be immobilized by a radical reaction induced by photoirradiation. Here, we prepared the microarray using a very convenient method. Aqueous solutions of each autoantigen were mixed with a polymer of poly(ethylene glycol) methacrylate and a photoreactive crosslinker, and the mixtures were microspotted on a plate and dried in air. Finally, the plate was irradiated with an ultraviolet lamp to obtain immobilization. In the assay, patient serum was added to the microarray plate. Antigen-specific IgG adsorbed on the microspotted autoantigen was detected by peroxidase-conjugated anti-IgG antibody. The chemical luminescence intensities of the substrate decomposed by the peroxidase were detected with a sensitive CCD camera. All autoantigens were immobilized stably by this method and used to screen antigen-specific IgG. In addition, the plate was covered with a polydimethylsiloxane sheet containing microchannels and automated measurement was carried out.

Contactin-1 and Neurofascin-155/-186 Are Not Targets of Auto-Antibodies in Multifocal Motor Neuropathy.

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Kathrin Doppler

Full Text Available Multifocal motor neuropathy is an immune mediated disease presenting with multifocal muscle weakness and conduction block. IgM auto-antibodies against the ganglioside GM1 are detectable in about 50% of the patients. Auto-antibodies against the paranodal proteins contactin-1 and neurofascin-155 and the nodal protein neurofascin-186 have been detected in subgroups of patients with chronic inflammatory demyelinating polyneuropathy. Recently, auto-antibodies against neurofascin-186 and gliomedin were described in more than 60% of patients with multifocal motor neuropathy. In the current study, we aimed to validate this finding, using a combination of different assays for auto-antibody detection. In addition we intended to detect further auto-antibodies against paranodal proteins, specifically contactin-1 and neurofascin-155 in multifocal motor neuropathy patients' sera. We analyzed sera of 33 patients with well-characterized multifocal motor neuropathy for IgM or IgG anti-contactin-1, anti-neurofascin-155 or -186 antibodies using enzyme-linked immunosorbent assay, binding assays with transfected human embryonic kidney 293 cells and murine teased fibers. We did not detect any IgM or IgG auto-antibodies against contactin-1, neurofascin-155 or -186 in any of our multifocal motor neuropathy patients. We conclude that auto-antibodies against contactin-1, neurofascin-155 and -186 do not play a relevant role in the pathogenesis in this cohort with multifocal motor neuropathy.

Use of Dried Capillary Blood Sampling for Islet Autoantibody Screening in Relatives: A Feasibility Study.

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Bingley, Polly J; Rafkin, Lisa E; Matheson, Della; Steck, Andrea K; Yu, Liping; Henderson, Courtney; Beam, Craig A; Boulware, David C

2015-12-01

Islet autoantibody testing provides the basis for assessment of risk of progression to type 1 diabetes. We set out to determine the feasibility and acceptability of dried capillary blood spot-based screening to identify islet autoantibody-positive relatives potentially eligible for inclusion in prevention trials. Dried blood spot (DBS) and venous samples were collected from 229 relatives participating in the TrialNet Pathway to Prevention Study. Both samples were tested for glutamic acid decarboxylase, islet antigen 2, and zinc transporter 8 autoantibodies, and venous samples were additionally tested for insulin autoantibodies and islet cell antibodies. We defined multiple autoantibody positive as two or more autoantibodies in venous serum and DBS screen positive if one or more autoantibodies were detected. Participant questionnaires compared the sample collection methods. Of 44 relatives who were multiple autoantibody positive in venous samples, 42 (95.5%) were DBS screen positive, and DBS accurately detected 145 of 147 autoantibody-negative relatives (98.6%). Capillary blood sampling was perceived as more painful than venous blood draw, but 60% of participants would prefer initial screening using home fingerstick with clinic visits only required if autoantibodies were found. Capillary blood sampling could facilitate screening for type 1 diabetes prevention studies.

Clinical significance of autoantibodies in autoimmune hepatitis.

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Liberal, Rodrigo; Mieli-Vergani, Giorgina; Vergani, Diego

2013-10-01

The accurate diagnosis and classification of autoimmune hepatitis (AIH) rely upon the detection of characteristic autoantibodies. Positivity for anti-nuclear (ANA) and/or anti-smooth muscle (SMA) autoantibodies defines AIH type 1 (AIH-1), whereas anti-liver kidney microsomal type 1 (anti-LKM1) and/or anti-liver cytosol type 1 (anti-LC1) define AIH type 2 (AIH-2). ANA and SMA, and less commonly anti-LKM1, have also been detected in de-novo autoimmune hepatitis developing after liver transplantation, a condition that may affect patients transplanted for non-autoimmune liver disease. The diagnostic autoantibodies associated with AIH-1 are also detected in the paediatric AIH/sclerosing cholangitis overlap syndrome, referred to as autoimmune sclerosing cholangitis (ASC). ASC, like adult primary sclerosing cholangitis, is often associated with atypical perinuclear anti-neutrophil cytoplasmic autoantibodies (p-ANCA), although p-ANCA are also detected in other autoimmune liver diseases. These associations highlight the necessity for simple and prompt diagnostic autoantibody testing, and the requirement for the accurate interpretation of the results of the tests in the clinical context. Fine-mapping of antigenic autoantibody targets has facilitated the development of rapid molecular assays that have the potential to revolutionise the field if properly standardised and when used in combination with classical immunofluorescence. Despite their diagnostic significance, the pathogenic role of the various autoantibodies and the mechanisms by which they can potentially inflict damage onto the liver cell remain a topic for further research. Copyright © 2013 Elsevier Ltd. All rights reserved.

Detection of autoantibodies to cytokines

DEFF Research Database (Denmark)

Bendtzen, K; Hansen, M B; Ross, C

2000-01-01

Autoantibodies to various cytokines have been reported in normal individuals and in patients with various infectious and immunoinflammatory disorders, and similar antibodies (Ab) may be induced in patients receiving human recombinant cytokines. The clinical relevance of these Ab is often difficult...... to evaluate. Not only are in vitro neutralizing cytokine Ab not necessarily neutralizing in vivo, but assays for binding and neutralizing Ab to cytokines are often difficult to interpret. For example, denaturation of immobilized cytokines in immunoblotting techniques and immunometric assays may leave Ab...

Two cases of erosive oral lichen planus with autoantibodies to desmoglein 3.

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Muramatsu, Ken; Nishie, Wataru; Natsuga, Ken; Fujita, Yasuyuki; Iwata, Hiroaki; Yamada, Tamaki; Yamashita, Emi; Asaka, Takuya; Shimizu, Hiroshi

2016-11-01

Oral lichen planus (OLP) is a chronic inflammatory disorder of the oral mucosa of unknown etiology. Clinically, the erosive type of OLP (erosive OLP) can show features similar to those of pemphigus vulgaris (PV), an autoimmune blistering disorder in which desmoglein (Dsg)3 is targeted. In addition to clinical and histopathological findings, immunological studies, including direct immunofluorescence (IF), indirect IF and enzyme-linked immunosorbent assay (ELISA) that detect autoantibodies to Dsg3, are helpful in differentiating erosive OLP from PV. Here, we show two cases of erosive OLP with autoantibodies to Dsg3. Patient 1 was a 68-year-old woman with chronic erosions of the oral mucosa, in which elevated levels of immunoglobulin (Ig)G autoantibodies to Dsg1 and Dsg3 were detected by ELISA. Patient 2 was an 85-year-old woman with white striae with erosions on the lateral sides of the buccal mucosa with elevated levels of IgG autoantibodies to Dsg3 detected by ELISA. Histopathological findings from both cases showed lichenoid dermatitis, and both direct and indirect IF showed no tissue-bound IgG autoantibodies. From these findings, the diagnosis of erosive OLP was made. Immunological assays revealed both cases to have IgG-directing calcium-independent linear epitopes on Dsg3, which are suggestive of non-pathogenic autoantibodies. In addition, autoantibodies to Dsg3 in patient 2 reacted with a prosequence-possessing precursor form of Dsg3 but not with the mature form of the molecule. The present study suggests that erosive OLP may develop anti-Dsg3 autoantibodies, which should be carefully assessed. © 2016 Japanese Dermatological Association.

A sensitive radio-immunoassay for serum thyroglobulin -including a correct screening for thyroglobulin autoantibodies

International Nuclear Information System (INIS)

Laurberg, Peter; Pedersen, K.M.

1987-01-01

A new thyroglobulin (Tg) assay employing polyethylene glycol (PEG) for separation of free and antibody bound : 125 I:Tg is described. By choosing a suitable PEG concentration the non-specific precipitation of free [ 125 I]Tg was kept low while both [ 125 I]Tg bound to rabbit anti-Tg immunoglobulins and to human Tg autoantibodies were precipitated. For all sera a 'blank' incubation with no rabbit anti-Tg immunoglobulins was run in parallel with the assay tubes. Hence any interference of Tg autoantibodies would be detected. A two-phase incubation gave a very low detection limit of 0.2 μg/l. The inter-assay coefficient of variation was 9.4% and the intra-assay coefficient of variation was 5.6%. Dilution curves of normal sera were parallel to the standard curve and Tg standards added to normal sera were recovered quantitatively. Twelve out of 60 normal sera from the Randers area contained Tg autoantibodies. The average serum Tg in the 48 sera without antibody was 44.6 ± 5.2 μg/l. (author)

Severe hypoglycaemia in a person with insulin autoimmune syndrome accompanied by insulin receptor anomaly type B.

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Kato, T; Itoh, M; Hanashita, J; Itoi, T; Matsumoto, T; Ono, Y; Imamura, S; Hayakawa, N; Suzuki, A; Mizutani, Y; Uchigata, Y; Oda, N

2007-11-01

A rare case of the insulin autoimmune syndrome (IAS) accompanied by insulin receptor anomaly is reported. Antibodies to insulin and insulin receptor were determined in the patient with severe hypoglycaemia before and after the treatment with prednisolone. Titers of antibody to insulin and insulin receptors were 73.0% and 41.5%, respectively. Drug-induced lymphocyte stimulation tests were all negative for the suspicious drugs. Her HLA-DR was DRB1*0403/04051. Following steroid therapy, the formation of antibodies was suppressed and alleviated her symptoms. Scatchard analysis yielded findings specific to polyclonal antibodies. The changes in autoantibodies resulted in alleviation of the hypoglycemic symptoms as a result of steroid therapy.

Measurement of antiacetylcholine receptor auto-antibodies in ...

African Journals Online (AJOL)

Two different acetylcholine receptor (AChR) preparations derived from amputated human muscle (AChRAMP) and from the human rhabdomyosarcoma cell line TE671 (AChRTE67,) were compared in radio-immunoprecipitation assays for the detection of AChR auto-antibodies in serum specimens from 20 patients with ...

A rapid, accurate and robust particle-based assay for the simultaneous screening of plasma samples for the presence of five different anti-cytokine autoantibodies

DEFF Research Database (Denmark)

Guldager, Daniel Kring Rasmussen; von Stemann, Jakob Hjorth; Larsen, Rune

2015-01-01

suitable for larger screenings. Based on confirmed antibody binding characteristics and the resultant reactivity in this multiplex assay, a classification of the c-aAb levels was suggested. The screening results of the recipients who received blood transfusions indicate that more studies are needed...... plasma samples and pooled normal immunoglobulin preparations were used to validate the assay. Plasma samples from 98 transfusion recipients, half of whom presented with febrile reactions, were tested by the assay. RESULTS: The assay detected specific and saturable immunoglobulin G (IgG) binding to each...... cytokine autoantibodies quantities in the negative plasma samples ranged between 80% and 125%. The analytical intra- and inter-assay variations were 4% and 11%, respectively. Varying c-aAb levels were detectable in the transfusion recipients. There was no difference in c-aAb frequency between the patients...

A rapid lateral flow immunoassay for the detection of tyrosine phosphatase-like protein IA-2 autoantibodies in human serum.

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Ingrid Kikkas

Full Text Available Type 1 diabetes (T1D results from the destruction of pancreatic insulin-producing beta cells and is strongly associated with the presence of islet autoantibodies. Autoantibodies to tyrosine phosphatase-like protein IA-2 (IA-2As are considered to be highly predictive markers of T1D. We developed a novel lateral flow immunoassay (LFIA based on a bridging format for the rapid detection of IA-2As in human serum samples. In this assay, one site of the IA-2As is bound to HA-tagged-IA-2, which is subsequently captured on the anti-HA-Tag antibody-coated test line on the strip. The other site of the IA-2As is bound to biotinylated IA-2, allowing the complex to be visualized using colloidal gold nanoparticle-conjugated streptavidin. For this study, 35 serum samples from T1D patients and 44 control sera from non-diabetic individuals were analyzed with our novel assay and the results were correlated with two IA-2A ELISAs. Among the 35 serum samples from T1D patients, the IA-2A LFIA, the in-house IA-2A ELISA and the commercial IA-2A ELISA identified as positive 21, 29 and 30 IA-2A-positive sera, respectively. The major advantages of the IA-2A LFIA are its rapidity and simplicity.

Quality control of insulin radioreceptor assay for human erythrocytes. Effect of ageing of mono-125I-Tyr-A14-insulin preparation

International Nuclear Information System (INIS)

Marttinen, A.; Pasternack, A.; Koivula, T.; Jokela, H.; Lehtinen, M.

1984-01-01

The quality control of insulin radioreceptor assay for human erythrocytes is based on the storage of erythrocyte preparations in Hepes buffer of pH 8.0, containing 10 g/l of albumin and 20 mmol/l of glucose. The change of erythrocytes into spherocytes and crenated cells reduces the apparent number of insulin receptors in a relatively constant way by less than 8% a week after 10 days of storage. At the same time the dissociation constants of the insulin-receptor complex increase rapidly. Thus the use of a preparation must be limited to controlling the determination of the insulin binding sites of erythrocytes, and not to the measurement of the affinities of the receptors. When mono- 125 I-Tyr-A14-insulin gets old, a slow decrease in the insulin binding sites can be measured, but the dissociation constants of the insulin receptor complex are not affected. (author)

Testing for myositis specific autoantibodies: Comparison between line blot and immunoprecipitation assays in 57 myositis sera.

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Cavazzana, Ilaria; Fredi, Micaela; Ceribelli, Angela; Mordenti, Cristina; Ferrari, Fabio; Carabellese, Nice; Tincani, Angela; Satoh, Minoru; Franceschini, Franco

2016-06-01

To analyze the performance of a line blot assay for the identification of autoantibodies in sera of patients affected by myositis, compared with immunoprecipitation (IP) as gold standard. 66 sera of patients with myositis (23 polymyositis, 8 anti-synthetase syndromes, 29 dermatomyositis and 6 overlap syndromes) were tested by commercial LB (Euroimmun, Lubeck, Germany); 57 sera were analyzed also by IP of K562 cell extract radiolabeled with (35)S-methionine. Inter-rater agreement was calculated with Cohen's k coefficient. Myositis-specific antibodies (MSA) were detected in 36/57 sera (63%) by IP and in 39/66 sera (59%) by LB. The most frequent MSA found by LB were anti-Jo1 and anti-Mi2 found in 15% (10/66) of sera, followed by anti-NXP2 and anti-SRP detected in 106% (7/66) of sera. Anti-TIF1gamma and anti-MDA5 were found in 6 (9%) and 5 sera (7.6%), respectively. A good agreement between methods was found only for anti-TIF1γ, anti-MDA5 and anti-NXP-2 antibodies, while a moderate agreement was estimated for anti-Mi2 and anti-EJ. By contrast, a high discordance rate for the detection of anti-Jo1 antibodies was evident (k: 0.3). Multiple positivity for MSA were found in 11/66 (17%) by LB and 0/57 by IP (p: 0001). Comparing the clinical features of these 11 sera, we found total discrepancies between assays in 3 sera (27.3%), a relative discrepancy due to the occurrence of one discordant autoantibody (not confirmed by IP) in 5 cases (45.5%) and a total discrepancy between LB and IP results, but with a relative concordance with clinical features were found in other 3 sera (27.3%). The semiquantitative results do not support the interpretation of the data. The use of LB assay allowed the detection of new MSA, such as anti-MDA5, anti-MJ and anti-TIF1gamma antibodies, previously not found with routine methods. However, the high prevalence of multiple positivities and the high discondant rate of anti-Jo1 antibodies could create some misinterpretation of the results from the

Clinical and Genetic Characteristics of Non-Insulin-Requiring Glutamic Acid Decarboxylase (GAD Autoantibody-Positive Diabetes: A Nationwide Survey in Japan.

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Junichi Yasui

Full Text Available Glutamic acid decarboxylase autoantibodies (GADAb differentiate slowly progressive insulin-dependent (type 1 diabetes mellitus (SPIDDM from phenotypic type 2 diabetes, but many GADAb-positive patients with diabetes do not progress to insulin-requiring diabetes. To characterize GADAb-positive patients with adult-onset diabetes who do not require insulin therapy for >5 years (NIR-SPIDDM, we conducted a nationwide cross-sectional survey in Japan.We collected 82 GADAb-positive patients who did not require insulin therapy for >5 years (NIR-SPIDDM and compared them with 63 patients with insulin-requiring SPIDDM (IR-SPIDDM. Clinical and biochemical characteristics, HLA-DRB1-DQB1 haplotypes, and predictive markers for progression to insulin therapy were investigated.Compared with the IR-SPIDDM group, the NIR-SPIDDM patients showed later diabetes onset, higher body mass index, longer duration before diagnosis, and less frequent hyperglycemic symptoms at onset. In addition, C-peptide, LDL-cholesterol, and TG were significantly higher in the NIR-SPIDDM compared to IR-SPIDDM patients. The NIR-SPIDDM group had lower frequency of susceptible HLA-DRB1*04:05-DQB1*04:01 and a higher frequency of resistant HLA-DRB1*15:01-DQB1*06:02 haplotype compared to IR-SPIDDM. A multivariable analysis showed that age at diabetes onset (OR = 0.82, duration before diagnosis of GADAb-positive diabetes (OR = 0.82, higher GADAb level (≥10.0 U/ml (OR = 20.41, and fasting C-peptide at diagnosis (OR = 0.07 were independent predictive markers for progression to insulin-requiring diabetes. An ROC curve analysis showed that the optimal cut-off points for discriminating two groups was the GADAb level of 13.6 U/ml, age of diabetes onset of 47 years, duration before diagnosis of 5 years, and fasting C-peptide of 0.65 ng/ml.Clinical, biochemical and genetic characteristics of patients with NIR-SPIDDM are different from those of IR-SPIDDM patients. Age of diabetes onset, duration before

Islet Autoantibody Patterns in Patients With Type 2 Diabetes Aged 60 and Higher: A Cross-Sectional Study in a Chinese Hospital

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Rumei Li

2018-05-01

Full Text Available BackgroundSome elderly citizens with a clinical diagnosis of type 2 diabetes had evidence of positive islet autoantibodies. We aimed to discover their islet autoantibody patterns and independent correlative factors that might lead to a better understanding of significance of islet autoimmunity in the progression of elderly diabetes.MethodsA total of 541 inpatients of clinically diagnosed type 2 diabetes aged 60 and over were recruited. Three islet autoantibodies including insulin autoantibody (IAA, islet cell antibody (ICA, and glutamic acid decarboxylase antibody (GADA as well as clinical and biochemical characteristics were tested and collected in Huashan Hospital. Associations between these antibodies and clinical features were analyzed by Spearman correlation and binary logistic analyses.ResultsIn our current study, total positive rate of islet autoantibodies (IAA, ICA, and GADA was 35.67% with 26.62% for individual IAA, 5.55% for ICA, and 5.91% for GADA, in elderly with type 2 diabetes. None of combinations of such autoantibodies were observed, with the exception of IAA + ICA (0.74%, n = 4, IAA + GADA (1.48%, n = 8, and ICA + GADA (0.18%, n = 1. Compared with GADA negative group, patients in positive group tended to have lower level of fasting and postprandial C peptide, fasting blood glucose (FBG, and body mass index (BMI. After adjusted for the BMI, FBG, and postprandial C peptide, fasting C peptide seemed to be an independent factor related to GADA positivity (OR = 0.52, p = 0.02. As for patients with positive IAA, they were more likely to have insulin treatment with longer duration of diabetes, higher level of BMI, and lower level of postprandial C peptide. After adjusted for the duration of diabetes, BMI, and postprandial C peptide, insulin treatment was a significant predictor for IAA positivity (OR = 5.20, p < 0.0001. Furthermore, hs-CRP was positively related to ICA positivity, and hs

Quality control of insulin radioreceptor assay for human erythrocytes. Effect of ageing of mono-/sup 125/I-Tyr-A14-insulin preparation

Energy Technology Data Exchange (ETDEWEB)

Marttinen, A; Pasternack, A [Tampere Univ. (Finland). Dept. of Clinical Sciences; Koivula, T; Jokela, H; Lehtinen, M [Tampere Univ. Central Hospital (Finland). Dept. of Clinical Chemistry

1984-09-01

The quality control of insulin radioreceptor assay for human erythrocytes is based on the storage of erythrocyte preparations in Hepes buffer of pH 8.0, containing 10 g/l of albumin and 20 mmol/l of glucose. The change of erythrocytes into spherocytes and crenated cells reduces the apparent number of insulin receptors in a relatively constant way by less than 8% a week after 10 days of storage. At the same time the dissociation constants of the insulin-receptor complex increase rapidly. Thus the use of a preparation must be limited to controlling the determination of the insulin binding sites of erythrocytes, and not to the measurement of the affinities of the receptors. When mono-/sup 125/I-Tyr-A14-insulin gets old, a slow decrease in the insulin binding sites can be measured, but the dissociation constants of the insulin receptor complex are not affected.

Autoantibodies in breast cancer sera are not epiphenomena and may participate in carcinogenesis

International Nuclear Information System (INIS)

Fernández Madrid, Félix; Maroun, Marie-Claire; Olivero, Ofelia A; Long, Michael; Stark, Azadeh; Grossman, Lawrence I; Binder, Walter; Dong, Jingsheng; Burke, Matthew; Nathanson, S David; Zarbo, Richard; Chitale, Dhananjay; Zeballos-Chávez, Rocío; Peebles, Carol

2015-01-01

The objective of this work was to demonstrate that autoantibodies in breast cancer sera are not epiphenomena, and exhibit unique immunologic features resembling the rheumatic autoimmune diseases. We performed a comprehensive study of autoantibodies on a collection of sera from women with breast cancer or benign breast disease, undergoing annual screening mammography. All women in this study had suspicious mammography assessment and underwent a breast biopsy. We used indirect immunofluorescence, the crithidia assay for anti-dsDNA antibodies, and multiple ELISAs for extractable nuclear antigens. Autoantibodies were detected in virtually all patients with breast cancer, predominantly of the IgG1 and IgG3 isotypes. The profile detected in breast cancer sera showed distinctive features, such as antibodies targeting mitochondria, centrosomes, centromeres, nucleoli, cytoskeleton, and multiple nuclear dots. The majority of sera showing anti-mitochondrial antibodies did not react with the M2 component of pyruvate dehydrogenase, characteristic of primary biliary cirrhosis. Anti-centromere antibodies were mainly anti-CENP-B. ELISAs for extractable nuclear antigens and the assays for dsDNA were negative. The distinctive autoantibody profile detected in BC sera is the expression of tumor immunogenicity. Although some of these features resemble those in the rheumatic autoimmune diseases and primary biliary cirrhosis, the data suggest the involvement of an entirely different set of epithelial antigens in breast cancer. High titer autoantibodies targeting centrosomes, centromeres, and mitochondria were detected in a small group of healthy women with suspicious mammography assessment and no cancer by biopsy; this suggests that the process triggering autoantibody formation starts in the pre-malignant phase and that future studies using validated autoantibody panels may allow detection of breast cancer risk in asymptomatic women. Autoantibodies developing in breast cancer are not

Tissue-specific methylation of human insulin gene and PCR assay for monitoring beta cell death.

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Mohamed I Husseiny

Full Text Available The onset of metabolic dysregulation in type 1 diabetes (T1D occurs after autoimmune destruction of the majority of pancreatic insulin-producing beta cells. We previously demonstrated that the DNA encoding the insulin gene is uniquely unmethylated in these cells and then developed a methylation-specific PCR (MSP assay to identify circulating beta cell DNA in streptozotocin-treated mice prior to the rise in blood glucose. The current study extends to autoimmune non-obese diabetic (NOD mice and humans, showing in NOD mice that beta cell death occurs six weeks before the rise in blood sugar and coincides with the onset of islet infiltration by immune cells, demonstrating the utility of MSP for monitoring T1D. We previously reported unique patterns of methylation of the human insulin gene, and now extend this to other human tissues. The methylation patterns of the human insulin promoter, intron 1, exon 2, and intron 2 were determined in several normal human tissues. Similar to our previous report, the human insulin promoter was unmethylated in beta cells, but methylated in all other tissues tested. In contrast, intron 1, exon 2 and intron 2 did not exhibit any tissue-specific DNA methylation pattern. Subsequently, a human MSP assay was developed based on the methylation pattern of the insulin promoter and human islet DNA was successfully detected in circulation of T1D patients after islet transplantation therapy. Signal levels of normal controls and pre-transplant samples were shown to be similar, but increased dramatically after islet transplantation. In plasma the signal declines with time but in whole blood remains elevated for at least two weeks, indicating that association of beta cell DNA with blood cells prolongs the signal. This assay provides an effective method to monitor beta cell destruction in early T1D and in islet transplantation therapy.

Autoantibodies and their antigens in autoimmune hepatitis.

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Bogdanos, Dimitrios P; Mieli-Vergani, Giorgina; Vergani, Diego

2009-08-01

Autoantibody detection assists in the diagnosis and allows differentiation of autoimmune hepatitis (AIH) type 1 (AIH-1), characterized by antinuclear antibody (ANA) and/or smooth muscle antibody (SMA), and type 2 (AIH-2), distinguished by the presence of antibodies to liver-kidney microsome type 1 (anti-LKM1) and/or antibodies to liver cytosol type 1 (anti-LC1). Detection of atypical perinuclear antineutrophil cytoplasmic antibodies (pANCA) and anti-soluble liver antigen (SLA) antibodies can act as an additional pointer toward the diagnosis of AIH, particularly in the absence of the conventional autoantibodies. Routine autoantibody testing by indirect immunofluorescence has been recently complemented by molecular assays based on purified or recombinant antigens. Although the AIH-1-specific ANA and SMA targets need better definition, those of anti-LKM1 and anti-LC1 in AIH-2 have been clearly identified; the fine specificity of antibody reactivity and its clinical relevance to disease pathogenesis are the focus of ongoing investigation. This article critically discusses the current knowledge of the diagnostic and clinical significance of AIH-related autoantibody reactivities, focusing on key issues that the physician needs to be aware of to be able to request the appropriate testing and to interpret correctly the laboratory results within the clinical context of the patient. Copyright Thieme Medical Publishers.

[Autoantibodies as biomarkers].

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Tron, François

2014-01-01

Activation and differentiation of autoreactive B-lymphocytes lead to the production of autoantibodies, which are thus the direct consequence of the autoimmune process. They often constitute biomarkers of autoimmune diseases and are measured by tests displaying various diagnosis sensitivity and specificity. Autoantibody titers can be correlated to the disease activity and certain autoantibody populations associated with particular clinical manifestations or tissue lesions. The demonstration that autoantibodies appear years before the onset of autoimmune diseases indicates that their presence in healthy individuals may be a predictive marker of the occurrence of disease. Certain autoantibodies could also be predictive markers of a therapeutic response to biologics and of the occurrence of side effects as well. Thus, autoantibodies are useful tools in the diagnosis and the management of patients with organ specific or non-organ specific autoimmune diseases at different steps of the autoimmune process. Copyright © 2013. Published by Elsevier Masson SAS.

Glycotoxin and Autoantibodies Are Additive Environmentally Determined Predictors of Type 1 Diabetes

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Beyan, Huriya; Riese, Harriette; Hawa, Mohammed I.; Beretta, Guisi; Davidson, Howard W.; Hutton, John C.; Burger, Huibert; Schlosser, Michael; Snieder, Harold; Boehm, Bernhard O.; Leslie, R. David

2012-01-01

In type 1 diabetes, diabetes-associated autoantibodies, including islet cell antibodies (ICAs), reflect adaptive immunity, while increased serum Nε-carboxymethyl-lysine (CML), an advanced glycation end product, is associated with proinflammation. We assessed whether serum CML and autoantibodies predicted type 1 diabetes and to what extent they were determined by genetic or environmental factors. Of 7,287 unselected schoolchildren screened, 115 were ICA+ and were tested for baseline CML and diabetes autoantibodies and followed (for median 7 years), whereas a random selection (n = 2,102) had CML tested. CML and diabetes autoantibodies were determined in a classic twin study of twin pairs discordant for type 1 diabetes (32 monozygotic, 32 dizygotic pairs). CML was determined by enzyme-linked immunosorbent assay, autoantibodies were determined by radioimmunoprecipitation, ICA was determined by indirect immunofluorescence, and HLA class II genotyping was determined by sequence-specific oligonucleotides. CML was increased in ICA+ and prediabetic schoolchildren and in diabetic and nondiabetic twins (all P < 0.001). Elevated levels of CML in ICA+ children were a persistent, independent predictor of diabetes progression, in addition to autoantibodies and HLA risk. In twins model fitting, familial environment explained 75% of CML variance, and nonshared environment explained all autoantibody variance. Serum CML, a glycotoxin, emerged as an environmentally determined diabetes risk factor, in addition to autoimmunity and HLA genetic risk, and a potential therapeutic target. PMID:22396204

Coeliac disease autoantibodies mediate significant inhibition of tissue transglutaminase.

LENUS (Irish Health Repository)

Byrne, Greg

2012-02-01

The detection of antibodies directed against tissue transglutaminase (tTG) in serum is a sensitive and specific test for suspected coeliac disease. tTG is a ubiquitous, multifunctional enzyme that has been implicated in many important physiological processes as well as the site-specific deamidation of glutamine residues in gluten-derived peptides. This modification of gluten peptides facilitates their binding to HLA-DQ2, which results in amplification of the T-cell response to gluten. The purpose of this study was to investigate the possibility that patient IgA autoantibodies directed against tTG interfere with the crosslinking activity of the enzyme. IgA autoantibodies against tTG were isolated\\/depleted from patient serum and tested for their capacity to interfere with tTG activity in vitro using a sensitive fluorescence-based activity assay. We have demonstrated that autoantibodies cause significant inhibition of tTG-mediated crosslinking at equimolar and 2:1 ratios of antibody to enzyme.

Glutamic acid decarboxylase autoantibody-positivity post-partum is associated with impaired β-cell function in women with gestational diabetes mellitus

DEFF Research Database (Denmark)

Lundberg, T. P.; Højlund, K.; Snogdal, L. S.

2015-01-01

AIMS: To investigate whether the presence of glutamic acid decarboxylase (GAD) autoantibodies post-partum in women with prior gestational diabetes mellitus was associated with changes in metabolic characteristics, including β-cell function and insulin sensitivity. METHODS: During 1997-2010, 407...... women with gestational diabetes mellitus were offered a 3-month post-partum follow-up including anthropometrics, serum lipid profile, HbA1c and GAD autoantibodies, as well as a 2-h oral glucose tolerance test (OGTT) with blood glucose, serum insulin and C-peptide at 0, 30 and 120 min. Indices of insulin...... similar age and prevalence of diabetes mellitus. Women who were GAD+ve had significantly higher 2-h OGTT glucose concentrations during their index-pregnancy (10.5 vs. 9.8 mmol/l, P = 0.001), higher fasting glucose (5.2 vs. 5.0 mmol/l, P = 0.02) and higher 2-h glucose (7.8 vs. 7.1 mmol/l, P = 0.05) post...

AUTOANTIBODIES TO GLUTAMIC ACID DECARBOXYLASE AS A PATHOGENETIC MARKER OF TYPE I DIABETES MELLITUS

OpenAIRE

N. V. Piven; L. N. Lukhverchyk; A. I. Burakovsky; N. V. Polegenkaya; M. V. Karpovich

2011-01-01

Abstract. A new method of enzyme-linked immunosorbent assay (in solid-phase ELISA format) has been developed to determine concentrations of autoantibodies to glutamic acid decarboxylase, as well as an evidencebased methodology is proposed for its medical implications, as a quantitative pathogenetic predictive marker of autoimmune diagnostics in type 1 diabetes mellitus. This technique could be implied for serial production of diagnostic reagent kits, aimed for detection of autoantibodies to g...

Diagnostic value of islet autoantibody assays practised in Russia. 1. Classic immunofluorescence islet cell antibody assay, immunoradiometric glutamic acid decarboxylase antibody assay, and ELISA tyrosine phosphatase antibody and insulin antibody assays

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Alexei V. Timofeev

2016-09-01

Conclusions. We recommend to use ICA, IA-2A and GADA tests surveyed in our study for diagnosis of DM type 1 and differential diagnosis of DM. We don’t recommend IA testing with an Orgentec Anti-Insulin ELISA kit for usage in clinical practice.

Strategies for building reference standards for autoantibodies

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Joanna eSheldon

2015-04-01

Full Text Available Producing robust, certified, traceable reference material for autoantibody testing is a vital element in maintaining the validity of results that are generated in the daily clinical laboratory routine. This is a huge challenge because of the high number of variables involved in the detection and measurement of the autoantibodies. The production of such materials is time consuming and needs rigorous attention to detail; this is best achieved by an overarching independent body who will oversee the process in a not for profit manner.Much effort has been made to build international standards for quantitative and qualitative assays based on monoclonal antibodies, obtained from affinity purification and plasmapheresis. The big challenge is to respect individual differences in immune response to the same antigen. A promising ongoing initiative is the construction of pools with monospecific samples from different individuals.

Studies on insulin receptor, 1

International Nuclear Information System (INIS)

Sakai, Yukio

1979-01-01

The present study was designed for the purpose of establishing a method of insulin radioreceptor assay using plasma membranes of guinea pigs as receptor sites. The results obtained are as follows: 1) Insulin receptor in the renal plasma membranes of guinea pigs showed a significantly high affinity to porcine insulin compared with that in the plasma membranes of guinea pig liver or rat kidney and liver. 2) In the insulin radioreceptor assay, an optimum condition was observed by the incubation at 4 0 C for 24 - 48 hours with 100 μg membrane protein of guinea pig kidney and 0.08 ng of 125 I-insulin. This assay method was specific for insulin and showed an accurate biological activity of insulin. 3) The recovery rate of insulin radioreceptor assay was 98.4% and dilution check up to 16 times did not influence on the result. An average of coefficient variation was 3.92% within assay. All of these results indicated the method to be satisfactory. 4) Glucose induced insulin release by perfusion method in isolated Langerhans islets of rats showed an identical pattern of reaction curves between radioreceptor assay and radioimmunoassay, although the values of radioreceptor assay was slightly low. 5) Insulin free serum produced by ultra filtration method was added to the standard assay medium. By this procedure, direct measurement of human serum by radioreceptor assay became possible. 6) The value of human serum insulin receptor binding activity by the radioreceptor assay showed a high correlation with that of insulin radioimmunoassay in sera of normal, borderline or diabetic type defined by glucose tolerance test. (author)

Mechanisms of Autoantibody-Induced Pathology

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Ralf J. Ludwig

2017-05-01

Full Text Available Autoantibodies are frequently observed in healthy individuals. In a minority of these individuals, they lead to manifestation of autoimmune diseases, such as rheumatoid arthritis or Graves’ disease. Overall, more than 2.5% of the population is affected by autoantibody-driven autoimmune disease. Pathways leading to autoantibody-induced pathology greatly differ among different diseases, and autoantibodies directed against the same antigen, depending on the targeted epitope, can have diverse effects. To foster knowledge in autoantibody-induced pathology and to encourage development of urgently needed novel therapeutic strategies, we here categorized autoantibodies according to their effects. According to our algorithm, autoantibodies can be classified into the following categories: (1 mimic receptor stimulation, (2 blocking of neural transmission, (3 induction of altered signaling, triggering uncontrolled (4 microthrombosis, (5 cell lysis, (6 neutrophil activation, and (7 induction of inflammation. These mechanisms in relation to disease, as well as principles of autoantibody generation and detection, are reviewed herein.

Recombinant protein to analyze autoantibodies to proteinase 3 in systemic vasculitis

NARCIS (Netherlands)

Rarok, AA; Huitema, MG; van der Leij, MJ; van der Geld, YM; Berthold, H; Schmitt, J; Stegeman, CA; Limburg, PC; Kallenberg, CGM

2003-01-01

The presence of antineutrophil cytoplasmic autoantibodies with specificity for proteinase 3 (PR3-ANCA) usually is detected by enzyme-linked immunosorbent assay (ELISA) with purified PR3 as a substrate. We studied the technical performance of direct and capture ELISA using a recombinant

Autoantibodies in Neuropsychiatric Disorders

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Carolin Hoffmann

2016-04-01

Full Text Available Little is known about the etiology of neuropsychiatric disorders. The identification of autoantibodies targeting the N-methyl-d-aspartate receptor (NMDA-R, which causes neurological and psychiatric symptoms, has reinvigorated the hypothesis that other patient subgroups may also suffer from an underlying autoimmune condition. In recent years, a wide range of neuropsychiatric diseases and autoantibodies targeting ion-channels or neuronal receptors including NMDA-R, voltage gated potassium channel complex (VGKC complex, α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPA-R, γ-aminobutyric acid receptor (GABA-R and dopamine receptor (DR were studied and conflicting reports have been published regarding the seroprevalence of these autoantibodies. A clear causative role of autoantibodies on psychiatric symptoms has as yet only been shown for the NMDA-R. Several other autoantibodies have been related to the presence of certain symptoms and antibody effector mechanisms have been proposed. However, extensive clinical studies with large multicenter efforts to standardize diagnostic procedures for autoimmune etiology and animal studies are needed to confirm the pathogenicity of these autoantibodies. In this review, we discuss the current knowledge of neuronal autoantibodies in the major neuropsychiatric disorders: psychotic, major depression, autism spectrum, obsessive-compulsive and attention-deficit/hyperactivity disorders.

Autoantibody detection in type 2 autoimmune hepatitis using a chimera recombinant protein.

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Vitozzi, Susana; Lapierre, Pascal; Djilali-Saiah, Idriss; Alvarez, Fernando

2002-04-01

Autoantibodies against cytochrome P450 2D6 (CYP2D6), known as anti-liver/kidney microsome type 1 (LKM1) and/or anti-human formiminotransferase cyclodeaminase, formally known as anti-liver cytosol type 1 (LC1) define type 2 autoimmune hepatitis (AIH). The aims of this work are to develop a sensitive and specific test to detect anti-LKM1 and/or anti-LC1 autoantibodies and to establish the prevalence of anti-LC1. Sera from children with type 2 AIH (n=48) and those from a control group (n=100) were evaluated for anti-LKM1 and anti-LC1 by Enzyme-Linked Immunosorbent Assay (ELISA) and Western blotting. Each serum sample was assayed for reactivity against formiminotransferase cyclodeaminase and CYP2D6 alone or as part of a recombinant chimera protein. By ELISA with recombinant chimera protein, 50 serum samples were positive, 48 from patients with type 2 AIH and 2 from patients with chronic hepatitis C. Twenty-five of 48 (52%) patients studied were positive for both CYP2D6 and LC1 autoantibodies. Anti-LC1, either as the only marker or associated with anti-LKM1, was positive in 34/48 (71%). By Western blotting, anti-LC1 was found in 27/48 (56%) patients. This ELISA technique has proven to be antigen-specific and more sensitive than Western blot for the detection of anti-LC1 and anti-LKM1 autoantibodies. The prevalence of anti-LC1 (71%) confirms it as an important immunomarker in type 2 AIH.

Celiac Disease-Specific TG2-Targeted Autoantibodies Inhibit Angiogenesis Ex Vivo and In Vivo in Mice by Interfering with Endothelial Cell Dynamics.

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Suvi Kalliokoski

Full Text Available A characteristic feature of celiac disease is the presence of circulating autoantibodies targeted against transglutaminase 2 (TG2, reputed to have a function in angiogenesis. In this study we investigated whether TG2-specific autoantibodies derived from celiac patients inhibit angiogenesis in both ex vivo and in vivo models and sought to clarify the mechanism behind this phenomenon. We used the ex vivo murine aorta-ring and the in vivo mouse matrigel-plug assays to address aforementioned issues. We found angiogenesis to be impaired as a result of celiac disease antibody supplementation in both systems. Our results also showed the dynamics of endothelial cells was affected in the presence of celiac antibodies. In the in vivo angiogenesis assays, the vessels formed were able to transport blood despite impairment of functionality after treatment with celiac autoantibodies, as revealed by positron emission tomography. We conclude that celiac autoantibodies inhibit angiogenesis ex vivo and in vivo and impair vascular functionality. Our data suggest that the anti-angiogenic mechanism of the celiac disease-specific autoantibodies involves extracellular TG2 and inhibited endothelial cell mobility.

Celiac Disease–Specific TG2-Targeted Autoantibodies Inhibit Angiogenesis Ex Vivo and In Vivo in Mice by Interfering with Endothelial Cell Dynamics

Science.gov (United States)

Kalliokoski, Suvi; Sulic, Ana-Marija; Korponay-Szabó, Ilma R.; Szondy, Zsuzsa; Frias, Rafael; Perez, Mileidys Alea; Martucciello, Stefania; Roivainen, Anne; Pelliniemi, Lauri J.; Esposito, Carla; Griffin, Martin; Sblattero, Daniele; Mäki, Markku; Kaukinen, Katri; Lindfors, Katri; Caja, Sergio

2013-01-01

A characteristic feature of celiac disease is the presence of circulating autoantibodies targeted against transglutaminase 2 (TG2), reputed to have a function in angiogenesis. In this study we investigated whether TG2-specific autoantibodies derived from celiac patients inhibit angiogenesis in both ex vivo and in vivo models and sought to clarify the mechanism behind this phenomenon. We used the ex vivo murine aorta-ring and the in vivo mouse matrigel-plug assays to address aforementioned issues. We found angiogenesis to be impaired as a result of celiac disease antibody supplementation in both systems. Our results also showed the dynamics of endothelial cells was affected in the presence of celiac antibodies. In the in vivo angiogenesis assays, the vessels formed were able to transport blood despite impairment of functionality after treatment with celiac autoantibodies, as revealed by positron emission tomography. We conclude that celiac autoantibodies inhibit angiogenesis ex vivo and in vivo and impair vascular functionality. Our data suggest that the anti-angiogenic mechanism of the celiac disease-specific autoantibodies involves extracellular TG2 and inhibited endothelial cell mobility. PMID:23824706

Characterization of human organ donors testing positive for type 1 diabetes-associated autoantibodies

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Wiberg, A; Granstam, A; Ingvast, S; Härkönen, T; Knip, M; Korsgren, O; Skog, O

2015-01-01

In this study we aim to describe the characteristics of non-diabetic organ donors with circulating diabetes-associated autoantibodies collected within the Nordic Network for Islet Transplantation. One thousand and thirty organ donors have been screened in Uppsala for antibodies against glutamic acid decarboxylase (GADA) and islet antigen-2 (IA-2A). The 32 non-diabetic donors that tested positive for GADA (3·3% of all non-diabetic donors) were studied in more detail, together with 32 matched controls. Mean age among the autoantibody-positive donors was 52·6 (range 21–74), family history of type 1 diabetes (T1D) was unknown, and no donor was genetically predisposed for T1D regarding the human leucocyte antigen (HLA) locus. Subjects were analysed for islet cell antibodies (ICA), insulin autoantibodies (IAA) and zinc transporter 8 antibodies (ZnT8A), and pancreas morphology and clinical data were examined. Eight non-diabetic donors tested positive for two antibodies and one donor tested positive for four antibodies. No insulitis or other signs of a diabetic process were found in any of the donors. While inflammatory cells were present in all donors, subjects with high GADA titres had significantly higher CD45 cell numbers in exocrine tissue than controls. The extent of fibrosis was more pronounced in autoantibody-positive donors, even in subjects with lower GADA titres. Notably, it is possible that events not related directly to T1D (e.g. subclinical pancreatitis) may induce autoantibodies in some cases. PMID:26313035

Comparative study of the enzyme linked immunosorbent assay (ELISA) and two radioimmunoassays (RIA'S) for in-sulin

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Klimes, I; Jurcovicova, J; Palkovic, M [Slovenska Akademia Vied, Bratislava (Czechoslovakia). Ustav Experimentalnej Endokrinologie

1978-06-30

The results of the quality control tests for enzyme linked immunosorbent assay (ELISA) were compared with the results of two different radioimmunoassays (RIA'S) for insulin. Using the manufacturer's procedure for the ELISA kit we found that the analytical variables such as assay sensitivity, recovery study and the 50% binding intercept were in good agreement with those obtained with the RIA method.

Autoantibodies in Senear-Usher Syndrome: Cross-Reactivity or Multiple Autoimmunity?

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María Elena Pérez-Pérez

2012-01-01

Full Text Available Senear-Usher syndrome or pemphigus erythematosus is a pathology that overlaps clinically and serologically with pemphigus foliaceus and lupus erythematosus. Skin biopsies of patients with pemphigus erythematosus reveal acantholysis and deposits of immunoglobulins in desmosomes, and they are positive in the lupus band test. In the present paper, we determined whether the autoantibodies associated with pemphigus erythematosus targeted a single antigen or multiple antigens as a result of the stimulation of independent B cell clones. Our present paper demonstrates that patients with pemphigus erythematosus produce both antiepithelial antibodies specific for desmoglein 1 and 3 and antinuclear antibodies specific for Ro, La, Sm, and double-stranded DNA antigens. After eluting specific anti-epithelial or anti-nuclear antibodies, which were recovered and tested using double-fluorescence assays, a lack of cross-reactivity was demonstrated between desmosomes and nuclear and cytoplasmic lupus antigens. This result suggests that autoantibodies in pemphigus erythematosus are directed against different antigens and that these autoantibodies are produced by independent clones. Given these clinical and serological data, we suggest that pemphigus erythematosus behaves as a multiple autoimmune disease.

A three-layer immunoradiometric assay for antibodies in different immunoglobulin classes and its application to the detection of chicken thyroglobulin autoantibodies and of antibodies to sheep erythrocytes

International Nuclear Information System (INIS)

Carvalho, L.C.P. de; Roitt, I.M.; Wick, G.

1980-01-01

A versatile solid-phase assay for detection of antibodies in different immunoglobulin classes is described. The assay has been applied to: (1) the detection of IgG and IgM antithyroglobulin autoantibodies in chickens with spontaneous autoimmune thyroiditis, and (2) the detection of anti-sheep cell antibodies in normal chickens. Thyroglobulin-coated plastic tubes or formaldehyde-fixed sheep erythrocytes were used as the solid phase. Antisera were added in succession to the solid-phase antigen so as to form 3 antibody layers: (1) chicken antibody against the solid-phase antigen; (2) heavy-chain-specific rabbit anti-chicken immunoglobulin; and (3) 125 I-labelled goat anti-rabbit immunoglobulin. The assay is suitable for routine determinations on large numbers of samples; its sensitivity enables small volumes of serum to be tested and allows considerable economy in the use of valuable class-specific antisera. The radiolabelled reagent can be readily applied to other assays employing rabbit antisera. (Auth.)

Insulin radioreceptor assay on murine splenic leukocytes and peripheral erythrocytes

International Nuclear Information System (INIS)

Shimizu, F.; Kahn, R.

1982-01-01

Insulin radioreceptor assays were developed using splenic leukocytes and peripheral erythrocytes from individual mice. Splenic leukocytes were prepared using an NH 4 Cl buffer which did not alter insulin binding, but gave much higher yields than density gradient methods. Mouse erythrocytes were isolated from heparinized blood by three passages over a Boyum gradient, and a similar buffer was used to separate cells from free [ 125 I]iodoinsulin at the end of the binding incubation. Insulin binding to both splenic leukocytes and peripheral erythrocytes had typical pH, temperature, and time dependencies, and increased linearly with an increased number of cells. Optimal conditions for the splenic leukocytes (6 x 10 7 /ml) consisted of incubation with [ 125 I]iodoinsulin at 15 C for 2 h in Hepes buffer, pH 8.0. In cells from 20 individual mice, the specific [ 125 I]iodoinsulin binding was 2.6 +/- 0.1% (SEM), and nonspecific binding was 0.3 +/- 0.04% (10.6% of total binding). Erythrocytes (2.8 x 10 9 /ml) were incubated with [ 125 ]iodoinsulin at 15 C for 2 h in Hepes buffer, pH 8.2. In cells from 25 individual mice, the specific [ 125 I]iodoinsulin binding was 4.5 +/- 0.2%, and nonspecific binding was 0.7 +/- 0.03% (13.6% of total binding). In both splenic leukocytes and peripheral erythrocytes, analysis of equilibrium binding data produced curvilinear Scatchard plots with approximately 3500 binding sites/leukocyte and 20 binding sites/erythrocyte. These data demonstrate that adequate numbers of splenic leukocytes and peripheral erythrocytes can be obtained from individual mice to study insulin binding in a precise and reproducible manner

Analysis of novel Sjogren's syndrome autoantibodies in patients with dry eyes.

Science.gov (United States)

Everett, Sandra; Vishwanath, Sahana; Cavero, Vanessa; Shen, Long; Suresh, Lakshmanan; Malyavantham, Kishore; Lincoff-Cohen, Norah; Ambrus, Julian L

2017-03-07

Dry eye is a common problem in Ophthalmology and may occur for many reasons including Sjogren's syndrome (SS). Recent studies have identified autoantibodies, anti-salivary gland protein 1 (SP1), anti-carbonic anhydrase 6 (CA6) and anti-parotid secretory protein (PSP), which occur early in the course of SS. The current studies were designed to evaluate how many patients with idiopathic dry eye and no evidence of systemic diseases from a dry eye practice have these autoantibodies. Patients from a dry eye clinic and normal controls were assessed by Schirmer's test for tear flow. Sera were assessed for autoantibodies using ELISA assays. Statistics was performed with Prism 7 software and student's unpaired t test. In this study 60% of the dry eye patients expressed one of these autoantibodies. Only 30% expressed one of the autoantibodies associated with long-standing SS, which are included in the diagnostic criteria for SS, anti-Ro and anti-La. Patients with disease for less than 2 years and mild dry eyes did not express anti-Ro or anti-La, while 25% expressed anti-SP1. Similar observations, with smaller numbers, were made when patients had not only dry eye but also dry mouth. Antibodies to SP1, CA6 and PSP occur in some patients with idiopathic dry eyes. Further studies will be needed to determine how many of these patients go on to develop systemic manifestations of SS. Testing for these autoantibodies may allow early recognition of patients with SS. This will lead to improved management of the patients and the development of new strategies to maintain normal lacrimal and salivary gland function in patients with SS.

Lack of association between folate-receptor autoantibodies and neural-tube defects.

LENUS (Irish Health Repository)

Molloy, Anne M

2009-07-09

BACKGROUND: A previous report described the presence of autoantibodies against folate receptors in 75% of serum samples from women with a history of pregnancy complicated by a neural-tube defect, as compared with 10% of controls. We sought to confirm this finding in an Irish population, which traditionally has had a high prevalence of neural-tube defects. METHODS: We performed two studies. Study 1 consisted of analysis of stored frozen blood samples collected from 1993 through 1994 from 103 mothers with a history of pregnancy complicated by a neural-tube defect (case mothers), 103 mothers with a history of pregnancy but no complication by a neural-tube defect (matched with regard to number of pregnancies and sampling dates), 58 women who had never been pregnant, and 36 men. Study 2, conducted to confirm that the storage of samples did not influence the folate-receptor autoantibodies, included fresh samples from 37 case mothers, 22 control mothers, 10 women who had never been pregnant, and 9 men. All samples were assayed for blocking and binding autoantibodies against folate receptors. RESULTS: In Study 1, blocking autoantibodies were found in 17% of case mothers, as compared with 13% of control mothers (odds ratio, 1.54; 95% confidence interval [CI], 0.70 to 3.39), and binding autoantibodies in 29%, as compared with 32%, respectively (odds ratio, 0.82; 95% CI, 0.44 to 1.50). Study 2 showed similar results, indicating that sample degradation was unlikely. CONCLUSIONS: The presence and titer of maternal folate-receptor autoantibodies were not significantly associated with a neural-tube defect-affected pregnancy in this Irish population.

AUTOANTIBODIES TO GLUTAMIC ACID DECARBOXYLASE AS A PATHOGENETIC MARKER OF TYPE I DIABETES MELLITUS

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N. V. Piven

2011-01-01

Full Text Available Abstract. A new method of enzyme-linked immunosorbent assay (in solid-phase ELISA format has been developed to determine concentrations of autoantibodies to glutamic acid decarboxylase, as well as an evidencebased methodology is proposed for its medical implications, as a quantitative pathogenetic predictive marker of autoimmune diagnostics in type 1 diabetes mellitus. This technique could be implied for serial production of diagnostic reagent kits, aimed for detection of autoantibodies to glutamic acid decarboxylase by means of ELISA approach. (Med. Immunol., 2011, vol. 13, N 2-3, pp 257-260

Should the negativity for islet cell autoantibodies be used in a prescreening for genetic testing in maturity-onset diabetes of the young? The case of autoimmunity-associated destruction of pancreatic β-cells in a family of HNF1A-MODY subjects.

Science.gov (United States)

Urbanová, Jana; Rypáčková, Blanka; Kučera, Petr; Anděl, Michal; Heneberg, Petr

2013-01-01

It was recently suggested that routine islet cell autoantibody testing should be performed to discriminate maturity-onset diabetes of the young (MODY) from type 1 diabetes mellitus (T1DM). This is the first report ever to describe the familial manifestation of T1DM autoimmunity in nonobese HNF1A-MODY subjects and the presence of islet antigen-2 (IA-2) antibodies in MODY subjects. Three nonobese subjects in an age range of 14-35 years were diagnosed with HNF1A-MODY (p. Arg159Gln mutation). All the tested subjects had detectable (but varying) levels of islet cell autoantibodies (i.e., antibodies against glutamate decarboxylase or IA-2) in the absence of other T1DM characteristics. They displayed long-term expression of intermediate fasting C-peptide levels, ketoacidosis was absent even in periods of spontaneous insulin withdrawal, and full dependence on externally administered insulin was not detected in any of them although better glycemic control was achieved when insulin was supplemented. The course of the disease was similar to that of the autoantibody-negative HNF1A-MODY subjects. The case questions the selectivity of autoantibodies as a marker of T1DM or late-onset autoimmune diabetes of adulthood (LADA) over MODY and challenges the use of autoantibodies as a universal negative marker of MODY in an effort to decrease the cost of health care, as it may eventually lead to the wrong diagnosis and thus to the incorrect treatment. Further research should involve examination of the autoantibody titers and prevalence in large and geographically diverse cohorts of MODY subjects selected for genetic testing (regardless of their autoantibody titers) as well as determination of the islet cell autoantibody kinetics in the course of MODY onset and progression. Copyright © 2013 S. Karger AG, Basel.

Diagnostic Utility of Auto-Antibodies in Inflammatory Muscle Diseases.

Science.gov (United States)

Allenbach, Y; Benveniste, O

2015-01-01

To date, there are four main groups of idiopathic inflammatory myopathies (IIM): polymyositis (PM), dermatomyositis (DM), immune-mediated necrotizing myopathy (IMNM) and sporadic inclusion body myositis; based on clinical presentation and muscle pathology. Nevertheless, important phenotypical differences (either muscular and/or extra-muscular manifestations) within a group persist. In recent years, the titration of different myositis-specific (or associated) auto-antibodies as a diagnostic tool has increased. This is an important step forward since it may facilitate, at a viable cost, the differential diagnosis between IIM and other myopathies. We have now routine access to assays for the detection of different antibodies. For example, IMNM are related to the presence of anti-SRP or anti-HMGCR. PM is associated with anti-synthetase antibodies (anti-Jo-1, PL-7, PL-12, OJ, and EJ) and DM with anti-Mi-2, anti-SAE, anti-TIF-1-γ and anti-NXP2 (both associated with cancer) or anti-MDA5 antibodies (associated with interstitial lung disease). Today, over 30 myositis specific and associated antibodies have been characterised, and all groups of myositis may present one of those auto-antibodies. Most of them allow identification of homogenous patient groups, more precisely than the classical international classifications of myositis. This implies that classification criteria could be modified accordingly, since these auto-antibodies delineate groups of patients suffering from myositis with consistent clinical phenotype (muscular and extra-muscular manifestations), common prognostic (cancer association, presence of interstitial lung disease, mortality and risk of relapse) and treatment responses. Nevertheless, since numerous auto-antibodies have been recently characterised, the exact prevalence of myositis specific antibodies remains to be documented, and research of new auto-antibodies in the remaining seronegative group is still needed.

Novel Autoantibody Serum and Cerebrospinal Fluid Biomarkers in Veterans with Gulf War Illness

Science.gov (United States)

2017-10-01

using Western blot and ELISA assays. PURPOSE: Development of peripheral biomarkers for GWI. Scope of the Research: Serum and plasma from 250 Gulf War...basic protein (MBP), Myelin Associated Glycoprotein (MAG), CaMKII, alpha-synuclein, GFAP, S100B, Western Blot, ELISA , chronic fatigue syndrome (CFS...Milestone(s) Achieved: Site 1, 4 and 5 serum and CSF data collected and set up for laboratory assays ( ELISA , western blot). Autoantibody data shipped

Transfer plate radioassay using adsorbed anti-insulin antibody to detect insulin secreted by islet cell cultures

International Nuclear Information System (INIS)

Scearce, R.M.; Oie, H.K.; Gazdar, A.F.; Chick, W.L.; Eisenbarth, G.S.

1981-01-01

A solid-phase radioimmunoassay for detection of insulin synthesized by islet cell clones is described. This assay employs anti-insulin antibody adsorbed onto fenestrated polyvinyl chloride 96-well plates ('transfer plates'). The calibrated aperture in the bottom of each transfer plate well permits fluid to enter the wells when transfer plates are lowered into microculture wells containing insulin. With this assay it is possible to rapidly screen hundreds of islet cell cultures for insulin production. The authors have used this assay to facilitate cloning of the RIN rat insulinoma cell line. The assay readily detects insulin synthesis by RIN cells and [ 125 I]insulin is not displaced by culture medium from cells which do not produce insulin. The transfer plate format should be applicable to semiautomate other radioimmunoassays. (Auth.)

Autoantibodies in a Three-Year-Old Girl with Visceral Leishmaniasis: A Potential Diagnostic Pitfall

Directory of Open Access Journals (Sweden)

Gholamreza Pouladfar

2016-01-01

Full Text Available Visceral leishmaniasis (VL, a life-threatening parasitic infection, is endemic in the Mediterranean region. Diagnosis of VL is based on epidemiologic, clinical, and laboratory findings. However, sometimes, clinical features and laboratory findings overlap with those of autoimmune diseases. In some cases, autoantibodies are detected in patients with VL and this could be a potential diagnostic pitfall. In this study, we have reported on a three-year-old girl from a VL-endemic area in Iran, who presented with prolonged fever and splenomegaly. Bone marrow examination, serologic tests, and the molecular PCR assay were performed; however, results were inconclusive. The levels of anti-double stranded DNA, cytoplasmic antineutrophil cytoplasmic autoantibody, and perinuclear antineutrophil cytoplasmic autoantibody were elevated and, at the end, splenic biopsy was performed. The splenic tissue PCR test detected the DNA of Leishmania infantum. The patient’s condition improved with anti-Leishmania therapy, and the autoantibodies disappeared within the following four months. Clinical presentations and laboratory findings of VL and autoimmune diseases may overlap in some patients.

Micro-plate radiobinding assay of autoantibody to glutamic acid decarboxylase

International Nuclear Information System (INIS)

Huang Gan; Jin Helai; Wang Xia; Li Hui; Zhang Song; Zhou Zhiguang

2008-01-01

Objective: The purpose of this study was to develop a high-throughput micro-plate radiobinding assay (RBA) of glutamic acid decarboxylase antibody (CAD-Ab) and to evaluate its clinical application. Methods: 35 S labeled GAD 65 antigen was incubated with sera for 24 h on a 96-well plate, and then transferred to the Millipore plate coated with protein A, which was washed with 4 degree C PBS buffer, and then counted by a liquid scintillation counter. The CAD-Ab results were expressed by WHO standard unit (U/ml). A total of 224 healthy controls, 162 patients with type 1 diabetes mellitus (T1DM) and 210 patients with newly diagnosed type 2 diabetes (T2DM) were recruited. A total of 119 T1DM and healthy eases with gradually changing GAD-Ab levels were selected to compare the consistency of micro-plate RBA with conventional radioligand assay (RLA). Blood samples were obtained from the peripheral vein and finger tip in 32 healthy controls, 35 T1DM and 24 T2DM patients, and tested with micro-plate RBA and then compared with the conventional RLA to investigate the reliability of finger tip sampling. Linear correlation, student's t-test, variance analysis and receiver operating characteristic (ROC) curve were performed using SPSS 11.5. Results: (1) The optimized conditions of micro-plate RBA included 2 μl serum incubated with 3 x 10 4 counts/min 35 S-CAD for 24 h under slow vibration, antigen-antibody compounds washed 10 times by 4 degree C PBS buffer, and radioactivity counted with Optiphase Supermix scintillation liquid. (2)The intra-batch CV of the micro-plate RBA was 3.8%-10.2%, and the inter-batch CV was 5.6%-11.9%. The linearity analysis showed a good correlation when the GAD-Ab in serum samples ranged from 40.3 to 664 U/ml and the detection limit of measurement was 3.6 U/ml. The results from Diabetes Autoantibody Standardization Program (DASP) 2005 showed that the sensitivity and specificity for GAD-Ab were 78% (39 positive among 50 new-onset T1DM) and 98% (2 positive

Absence of anti-hypocretin receptor 2 autoantibodies in post pandemrix narcolepsy cases.

Directory of Open Access Journals (Sweden)

Guo Luo

Full Text Available A recent publication suggested molecular mimicry of a nucleoprotein (NP sequence from A/Puerto Rico/8/1934 (PR8 strain, the backbone used in the construction of the reassortant strain X-179A that was used in Pandemrix® vaccine, and reported on anti-hypocretin (HCRT receptor 2 (anti-HCRTR2 autoantibodies in narcolepsy, mostly in post Pandemrix® narcolepsy cases (17 of 20 sera. In this study, we re-examined this hypothesis through mass spectrometry (MS characterization of Pandemrix®, and two other pandemic H1N1 (pH1N1-2009 vaccines, Arepanrix® and Focetria®, and analyzed anti-HCRTR2 autoantibodies in narcolepsy patients and controls using three independent strategies.MS characterization of Pandemrix® (2 batches, Arepanrix® (4 batches and Focetria® (1 batch was conducted with mapping of NP 116I or 116M spectrogram. Two sets of narcolepsy cases and controls were used: 40 post Pandemrix® narcolepsy (PP-N cases and 18 age-matched post Pandemrix® controls (PP-C, and 48 recent (≤6 months early onset narcolepsy (EO-N cases and 70 age-matched other controls (O-C. Anti-HCRTR2 autoantibodies were detected using three strategies: (1 Human embryonic kidney (HEK 293T cells with transient expression of HCRTR2 were stained with human sera and then analyzed by flow cytometer; (2 In vitro translation of [35S]-radiolabelled HCRTR2 was incubated with human sera and immune complexes of autoantibody and [35S]-radiolabelled HCRTR2 were quantified using a radioligand-binding assay; (3 Optical density (OD at 450 nm (OD450 of human serum immunoglobulin G (IgG binding to HCRTR2 stably expressed in Chinese hamster ovary (CHO-K1 cell line was measured using an in-cell enzyme-linked immunosorbent assay (ELISA.NP 116M mutations were predominantly present in all batches of Pandemrix®, Arepanrix® and Focetria®. The wild-type NP109-123 (ILYDKEEIRRIWRQA, a mimic to HCRTR234-45 (YDDEEFLRYLWR, was not found to bind to DQ0602. Three or four subjects were found positive

Anti-pentraxin 3 auto-antibodies might be protective in lupus nephritis: a large cohort study.

Science.gov (United States)

Yuan, Mo; Tan, Ying; Pang, Yun; Li, Yong-Zhe; Song, Yan; Yu, Feng; Zhao, Ming-Hui

2017-11-01

Anti-pentraxin 3 (PTX3) auto-antibodies were found to be associated with the absence of renal involvement in systemic lupus erythematosus (SLE). This study is to investigate the prevalence of anti-PTX3 auto-antibodies and their clinical significance based on a large Chinese lupus nephritis cohort. One hundred and ninety-six active lupus nephritis patients, 150 SLE patients without clinical renal involvement, and 100 healthy controls were enrolled. Serum anti-PTX3 auto-antibodies and PTX3 levels were screened by enzyme-linked immunosorbent assay (ELISA). The associations between anti-PTX3 auto-antibodies and clinicopathological parameters in lupus nephritis were further analyzed. Anti-PTX3 auto-antibodies were less prevalent in active lupus nephritis patients compared with SLE without renal involvement (19.4% (38/196) versus 40.7% (61/150), p auto-antibodies were negatively correlated with proteinuria in lupus nephritis (r = -.143, p = .047). The levels of proteinuria, serum creatinine, and the prevalence of thrombotic microangiopathy were significantly higher in patients with higher PTX3 levels (≥3.207 ng/ml) and without anti-PTX3 auto-antibodies compared with patients with lower PTX3 levels (auto-antibodies (4.79 (3.39-8.28) versus 3.95 (1.78-7.0), p = .03; 168.84 ± 153.63 versus 101.44 ± 47.36, p = .01; 34.1% (14/41) versus 0% (0/9), p = .04; respectively). Anti-PTX3 auto-antibodies were less prevalent in active lupus nephritis patients compared with SLE without renal involvement and associated with less severe renal damage, especially with the combined evaluation of serum PTX3 levels.

Non-organ specific autoantibodies in children with chronic hepatitis C.

Science.gov (United States)

Bortolotti, F; Vajro, P; Balli, F; Giacchino, R; Crivellaro, C; Barbera, C; Cataleta, M; Muratori, L; Pontisso, P; Nebbia, G; Zancan, L; Bertolini, A; Alberti, A; Bianchi, F

1996-11-01

Recent studies in adult patients have established a relationship between hepatitis C virus infection and the presence of liver-kidney microsomal autoantibody type 1 (LKM1). Conversely, little is known regarding the relationship between hepatitis C and autoimmunity in children. In this study, we investigated non-organ specific autoantibodies in 40 otherwise healthy Italian children with chronic hepatitis C. All but four patients included in the study were asymptomatic. Liver histology, obtained in 35, showed features ranging from minimal to mild chronic hepatitis. Autoantibodies were investigated by indirect immunofluorescence. HCV RNA was assayed by the polymerase chain reaction in 34 cases and viral genotypes were determined. Antinuclear antibodies were detected in three (7.5%) cases, one with a homogeneous pattern; smooth muscle autoantibodies in seven (17.5%) cases, always with V (vessels only) specificity and LKM1 in four (10%), at titers ranging from 1:20 and 1:2560. Clinical and virologic features did not significantly differ between autoantibody positive and negative cases, although infections with HCV genotypes 1a and 2 were more frequent in LKM1-positive patients. During observation, the child with the highest LKM1 titre was unsuccessfully treated with alpha interferon but responded to steroids. Twelve LKM1 negative children were also treated with interferon and one developed low LKM1 titers concomitant with an alanine aminotransferase flare. The sera of the five LKM1-positive children with investigated by immunoblotting with a human microsomal fraction and peptide 257-269 of cytochrome P450IID6. Only the serum of the child with the highest LKM1 titers was reactive. These results show that a consistent proportion of children with chronic hepatitis C circulate non-organ specific autoantibodies. The prevalence of LKM1 is greater than in adults and this could raise problems for the treatment of the disease with interferon. The analysis of LKM1 target antigens

Cord blood insulinoma-associated protein 2 autoantibodies are associated with increased risk of type 1 diabetes in the population-based Diabetes Prediction in Skåne study.

Science.gov (United States)

Lundgren, Markus; Lynch, Kristian; Larsson, Christer; Elding Larsson, Helena

2015-01-01

The aim of this study was to examine the effect of cord blood autoantibodies on the risk for type 1 diabetes in children followed prospectively from birth. The Diabetes Prediction in Skåne (DiPiS) study consists of 35,853 children from the general population born during 2000-2004. Samples were collected at birth and analysed for HLA genotypes and autoantibodies to glutamate decarboxylase 65 (GAD65), insulin and insulinoma-associated protein 2 (IA-2). After adjusting for HLA, sex, maternal age and parental type 1 diabetes, independent associations with risk of diabetes were assessed using multivariate Cox proportional hazards models. In total, 151 children (0.4%) had developed type 1 diabetes by the end of 2013 at a median age of 5.8 years (0.8-12.2 years). In the multivariate analysis, the presence of IA-2 autoantibodies (IA-2A) in cord blood (HR 6.88, 95% CI 1.46,32.4; p = 0.003), but not maternal diabetes (HR 1.38, 95% CI 0.24,7.84; p = 0.71), was associated with risk of developing type 1 diabetes. No increased risk could be seen for the presence of autoantibodies to GAD65 or insulin. Our study indicates that the presence of cord blood IA-2A superimposes maternal diabetes and other cord blood islet autoantibodies as a predictor of type 1 diabetes development in the child. These findings may be of significance for future screening and study protocols on type 1 diabetes prediction.

Frequency and levels of autoantibodies in healthy adult Omanis

International Nuclear Information System (INIS)

Al-Jabri, Ali A.; A-Belushi Mohammad; Nanze, Herburt

2003-01-01

A previous pilot study showed high frequency of anti-smooth muscle autoantibody in Omani blood donors and pregnant women. We conducted this larger-scale study to investigate the frequency and significance of several autoantibodies in healthy individuals from different regions of Oman. Sera obtained from 1537 healthy Omanis (1153 males and 384 females ), ranging in age from 18 to 57 years, tested for the presence of ten different autoantibodies using indirect immunofluoresence, haemagglutination and latex agglutination techniques. Low levels of autoantibodies were detected in 33.5%, whereas a few individuals (1.8%) showed high autoantibody titres. Anti-smooth muscle autoantibodies (ASMA) were the most prevalent (11%). Anti-nuclear autoantibodies (ANA) were the second most prevalent (7.6%). Anti-thyroid microsomal autoantibodies (ATMA) and anti-thyroglobulin autoantibodies (ATA) were present in 6.5% and 4.4% of individuals,respectively. The other autoantibodies were detected much less frequently: anti-parietal cells autoandibodies (APCA) were found in 1.6%,anti-brush border antibodies (ABBA) in 1.3% anti-reticulin autoantibodies (ARA) in 1%, anti-mitochondrial antibodies in 0.8%, antiglomerular basement membrane antibodies (AGBMA) in 0.7% and rheumatoid factor(RF) in 0.4%.Low levels of autoantibodies were detected in 33.5%, whereas a few individuals (1.8%) showed high autoantibody titres. Anti-smooth muscle autoantibodies (ASMA) were the most prevalent (11%). Anti-nuclear autoantibodies (ANA) were the second most prevalent (7.6%). Anti-thyroid microsomal autoantibodies (ATMA) and anti-thyroglobulin autoantibodies (ATA) were present in 6.5% and 4.4% of individuals,respectively. The other autoantibodies were detected much less frequently: anti-parietal cells autoandibodies (APCA) were found in 1.6%,anti-brush border antibodies (ABBA) in 1.3% anti-reticulin autoantibodies (ARA) in 1%, anti-mitochondrial antibodies in 0.8%, antiglomerular basement membrane antibodies

Luminescent Immunoprecipitation System (LIPS) for Detection of Autoantibodies Against ATP4A and ATP4B Subunits of Gastric Proton Pump H+,K+-ATPase in Atrophic Body Gastritis Patients

Science.gov (United States)

Lahner, Edith; Brigatti, Cristina; Marzinotto, Ilaria; Carabotti, Marilia; Scalese, Giulia; Davidson, Howard W; Wenzlau, Janet M; Bosi, Emanuele; Piemonti, Lorenzo; Annibale, Bruno; Lampasona, Vito

2017-01-01

Objectives: Circulating autoantibodies targeting the H+/K+-ATPase proton pump of gastric parietal cells are considered markers of autoimmune gastritis, whose diagnostic accuracy in atrophic body gastritis, the pathological lesion of autoimmune gastritis, remains unknown. This study aimed to assess autoantibodies against ATP4A and ATP4B subunits of parietal cells H+, K+-ATPase in atrophic body gastritis patients and controls. Methods: One-hundred and four cases with atrophic body gastritis and 205 controls were assessed for serological autoantibodies specific for ATP4A or ATP4B subunits using luminescent immunoprecipitation system (LIPS). Recombinant luciferase-reporter-fused-antigens were expressed by in vitro transcription-translation (ATP4A) or after transfection in Expi293F cells (ATP4B), incubated with test sera, and immune complexes recovered using protein-A-sepharose. LIPS assays were compared with a commercial enzyme immunoassay (EIA) for parietal cell autoantibodies. Results: ATP4A and ATP4B autoantibody titers were higher in cases compared to controls (Pgastritis. Both assays had the highest sensitivity, at the cost of diagnostic accuracy (89 and 90% specificity), outperforming traditional EIA. Once validated, these LIPS assays should be valuable screening tools for detecting biomarkers of damaged atrophic oxyntic mucosa. PMID:28102858

Time to insulin initiation can not be used in defining Latent Autoimmune Diabetes in Adults [LADA

DEFF Research Database (Denmark)

Brophy, S; Yderstræde, K; Mauricio, D

2007-01-01

and clinicians reported on criteria for initiating insulin. All patients were tested for glutamic acid decarboxylase autoantibodies (GADA) in a central laboratory. We examined time to insulin treatment for GADA positive patients in 6 participating centres. Results: There was inter-centre variation......Objective: Latent Autoimmune Diabetes in Adults [LADA] is type 1 diabetes presenting as non-insulin dependent diabetes. One feature of the selection criteria is time independent of insulin treatment. We examine the validity of this criterion. Methods: Patients were recruited in 9 European centres...

Detection of anti-aquaporin-4 autoantibodies in the sera of Chinese neuromyelitis optica patients

Institute of Scientific and Technical Information of China (English)

Miao Li; Weiheng Su; Jie Wang; Francesco Pisani; Antonio Frigeri; Tonghui Ma

2013-01-01

In this study, we recruited 10 neuromyelitis optica patients, two multiple sclerosis patients and two myelitis patients. Chinese hamster lung fibroblast (V79) cells transfected with a human aquaporin-4-mCherry fusion protein gene were used to detect anti-aquaporin-4 antibody in neuromyelitis optica patient sera by immunofluorescence. Anti-aquaporin-4 autoantibody was stably detected by immunofluorescence in neuromyelitis optica patient sera exclusively. The sensitivity of the assay for neuromyelitis optica was 90% and the specificity for neuromyelitis optica was 100%. The anti-aquaporin-4 antibody titers in sera were tested with serial dilutions until the signal disappeared. A positive correlation was detected between Expanded Disability Status Scale scores and serum anti-aquaporin-4 antibody titers. The anti-aquaporin-4 antibody assay is highly sensitive and specific in the sera of Chinese neuromyelitis optica patients. Detection of aquaporin-4 autoantibody is important for the diagnosis and treatment of neuromyelitis optica.

Detection of anti-aquaporin-4 autoantibodies in the sera of Chinese neuromyelitis optica patients.

Science.gov (United States)

Li, Miao; Su, Weiheng; Wang, Jie; Pisani, Francesco; Frigeri, Antonio; Ma, Tonghui

2013-03-15

In this study, we recruited 10 neuromyelitis optica patients, two multiple sclerosis patients and two myelitis patients. Chinese hamster lung fibroblast (V79) cells transfected with a human aquaporin-4-mCherry fusion protein gene were used to detect anti-aquaporin-4 antibody in neuromyelitis optica patient sera by immunofluorescence. Anti-aquaporin-4 autoantibody was stably detected by immunofluorescence in neuromyelitis optica patient sera exclusively. The sensitivity of the assay for neuromyelitis optica was 90% and the specificity for neuromyelitis optica was 100%. The anti-aquaporin-4 antibody titers in sera were tested with serial dilutions until the signal disappeared. A positive correlation was detected between Expanded Disability Status Scale scores and serum anti-aquaporin-4 antibody titers. The anti-aquaporin-4 antibody assay is highly sensitive and specific in the sera of Chinese neuromyelitis optica patients. Detection of aquaporin-4 autoantibody is important for the diagnosis and treatment of neuromyelitis optica.

Detection of anti-aquaporin-4 autoantibodies in the sera of Chinese neuromyelitis optica patients★

Science.gov (United States)

Li, Miao; Su, Weiheng; Wang, Jie; Pisani, Francesco; Frigeri, Antonio; Ma, Tonghui

2013-01-01

In this study, we recruited 10 neuromyelitis optica patients, two multiple sclerosis patients and two myelitis patients. Chinese hamster lung fibroblast (V79) cells transfected with a human aquaporin-4-mCherry fusion protein gene were used to detect anti-aquaporin-4 antibody in neuromyelitis optica patient sera by immunofluorescence. Anti-aquaporin-4 autoantibody was stably detected by immunofluorescence in neuromyelitis optica patient sera exclusively. The sensitivity of the assay for neuromyelitis optica was 90% and the specificity for neuromyelitis optica was 100%. The anti-aquaporin-4 antibody titers in sera were tested with serial dilutions until the signal disappeared. A positive correlation was detected between Expanded Disability Status Scale scores and serum anti-aquaporin-4 antibody titers. The anti-aquaporin-4 antibody assay is highly sensitive and specific in the sera of Chinese neuromyelitis optica patients. Detection of aquaporin-4 autoantibody is important for the diagnosis and treatment of neuromyelitis optica. PMID:25206717

Autoantibodies to MUC1 glycopeptides cannot be used as a screening assay for early detection of breast, ovarian, lung or pancreatic cancer

DEFF Research Database (Denmark)

Burford, B; Gentry-Maharaj, A; Graham, R

2013-01-01

Autoantibodies have been detected in sera before diagnosis of cancer leading to interest in their potential as screening/early detection biomarkers. As we have found autoantibodies to MUC1 glycopeptides to be elevated in early-stage breast cancer patients, in this study we analysed these autoanti...

Generation of Antigen Microarrays to Screen for Autoantibodies in Heart Failure and Heart Transplantation.

Directory of Open Access Journals (Sweden)

Andrzej Chruscinski

Full Text Available Autoantibodies directed against endogenous proteins including contractile proteins and endothelial antigens are frequently detected in patients with heart failure and after heart transplantation. There is evidence that these autoantibodies contribute to cardiac dysfunction and correlate with clinical outcomes. Currently, autoantibodies are detected in patient sera using individual ELISA assays (one for each antigen. Thus, screening for many individual autoantibodies is laborious and consumes a large amount of patient sample. To better capture the broad-scale antibody reactivities that occur in heart failure and post-transplant, we developed a custom antigen microarray technique that can simultaneously measure IgM and IgG reactivities against 64 unique antigens using just five microliters of patient serum. We first demonstrated that our antigen microarray technique displayed enhanced sensitivity to detect autoantibodies compared to the traditional ELISA method. We then piloted this technique using two sets of samples that were obtained at our institution. In the first retrospective study, we profiled pre-transplant sera from 24 heart failure patients who subsequently received heart transplants. We identified 8 antibody reactivities that were higher in patients who developed cellular rejection (2 or more episodes of grade 2R rejection in first year after transplant as defined by revised criteria from the International Society for Heart and Lung Transplantation compared with those who did have not have rejection episodes. In a second retrospective study with 31 patients, we identified 7 IgM reactivities that were higher in heart transplant recipients who developed antibody-mediated rejection (AMR compared with control recipients, and in time course studies, these reactivities appeared prior to overt graft dysfunction. In conclusion, we demonstrated that the autoantibody microarray technique outperforms traditional ELISAs as it uses less patient

Measurements of auto-antibodies to α-synuclein in the serum and cerebral spinal fluids of patients with Parkinson's disease.

Science.gov (United States)

Akhtar, Rizwan S; Licata, Joseph P; Luk, Kelvin C; Shaw, Leslie M; Trojanowski, John Q; Lee, Virginia M-Y

2018-03-03

Biomarkers for α-synuclein are needed for diagnosis and prognosis in Parkinson's disease (PD). Endogenous auto-antibodies to α-synuclein could serve as biomarkers for underlying synucleinopathy, but previous assessments of auto-antibodies have shown variability and inconsistent clinical correlations. We hypothesized that auto-antibodies to α-synuclein could be diagnostic for PD and explain its clinical heterogeneity. To test this hypothesis, we developed an enzyme-linked immunosorbent assay for measuring α-synuclein auto-antibodies in human samples. We evaluated 69 serum samples (16 healthy controls (HC) and 53 PD patients) and 145 CSF samples (52 HC and 93 PD patients) from our Institution. Both serum and CSF were available for 24 participants. Males had higher auto-antibody levels than females in both fluids. CSF auto-antibody levels were significantly higher in PD patients as compared to HC, whereas serum levels were not significantly different. CSF auto-antibody levels did not associate with amyloid-β 1-42 , total tau, or phosphorylated tau. CSF auto-antibody levels correlated with performance on the Montreal Cognitive Assessment, even when controlled for CSF amyloidβ 1-42 . CSF hemoglobin levels, as a proxy for contamination of CSF by blood during lumbar puncture, did not influence these observations. Using recombinant α-synuclein with N- and C-terminal truncations, we found that CSF auto-antibodies target amino acids 100 through 120 of α-synuclein. We conclude that endogenous CSF auto-antibodies are significantly higher in PD patients as compared to HC, suggesting that they could indicate the presence of underlying synucleinopathy. These auto-antibodies associate with poor cognition, independently of CSF amyloidβ 1-42 ., and target a select C-terminal region of α-synuclein. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Impact of Age and Antibody Type on Progression From Single to Multiple Autoantibodies in Type 1 Diabetes Relatives.

Science.gov (United States)

Bosi, Emanuele; Boulware, David C; Becker, Dorothy J; Buckner, Jane H; Geyer, Susan; Gottlieb, Peter A; Henderson, Courtney; Kinderman, Amanda; Sosenko, Jay M; Steck, Andrea K; Bingley, Polly J

2017-08-01

Islet autoantibodies are markers of type 1 diabetes, and an increase in number of autoantibodies detected during the preclinical phase predicts progression to overt disease. To refine the effect of age in relation to islet antibody type on progression from single to multiple autoantibodies in relatives of people with type 1 diabetes. We examined 994 relatives with normal glucose tolerance who were positive for a single autoantibody, followed prospectively in the TrialNet Pathway to Prevention. Antibodies to glutamic acid decarboxylase (GADA), insulin (IAA), insulinoma-associated antigen 2, and zinc transporter 8 and islet cell antibodies were tested every 6 to 12 months. The primary outcome was confirmed development of multiple autoantibodies. Age was categorized as <8 years, 8 to 11 years, 12 to 17 years, and ≥18 years, and optimal age breakpoints were identified by recursive partitioning analysis. After median follow-up of 2 years, 141 relatives had developed at least one additional autoantibodies. Five-year risk was inversely related to age, but the pattern differed by antibody type: Relatives with GADA showed a gradual decrease in risk over the four age groups, whereas relatives with IAA showed a sharp decrease above age 8 years. Recursive partitioning analysis identified age breakpoints at 14 years in relatives with GADA and at 4 years in relatives with IAA. In relatives with IAA, spread of islet autoimmunity is largely limited to early childhood, whereas immune responses initially directed at glutamic acid decarboxylase can mature over a longer period. These differences have important implications for monitoring these patients and for designing prevention trials. Copyright © 2017 Endocrine Society

Oropharyngeal Dysphagia in Dermatomyositis: Associations with Clinical and Laboratory Features Including Autoantibodies

OpenAIRE

Mugii, Naoki; Hasegawa, Minoru; Matsushita, Takashi; Hamaguchi, Yasuhito; Oohata, Sacihe; Okita, Hirokazu; Yahata, Tetsutarou; Someya, Fujiko; Inoue, Katsumi; Murono, Shigeyuki; Fujimoto, Manabu; Takehara, Kazuhiko

2016-01-01

Objective Dysphagia develops with low frequency in patients with dermatomyositis. Our objective was to determine the clinical and laboratory features that can estimate the development of dysphagia in dermatomyositis. Methods This study included 92 Japanese patients with adult-onset dermatomyositis. The associations between dysphagia and clinical and laboratory features including disease-specific autoantibodies determined by immunoprecipitation assays were analyzed. Results Videofluoroscopy sw...

The Attainment of High Sensitivity and Precision in Radioimmunoassay Techniques as Exemplified in a Simple Assay of Serum Insulin

Energy Technology Data Exchange (ETDEWEB)

Albano, Janet; Ekins, R. P. [Institute of Nuclear Medicine, Middlesex Hospital Medical School, London (United Kingdom)

1970-02-15

Recent controversy has underlined the fundamental confusion surrounding the concepts of assay ''sensitivity'' and ''precision'' and, in particular, their optimization in radioimmunoassay and other saturation assay procedures. Many formal definitions of sensitivity (e.g. that laid down by the American Chemical Society) express this concept in terms of the slope of the ''dose'' response curve; nevertheless, in common usage, the term is normally regarded as a synonym for the detection limit of the measurement technique. However, a technique which is ''sensitive'' in the formal sense may not display a low limit of detection, and it is readily demonstrable that, in radioimmunoassay systems in particular, there are circumstances in which increase in the slope of the response curve may lead to an increase in the detection limit of the assay. The authors have based their insulin assay protocols on mathematical principles specifically designed to lead to the minimization of the detection limit. The method depends on the use of (uncoated) charcoal for the separation of free and bound labelled insulin in incubation mixtures in which insulin-free human serum is used as diluent. The detection limit of the method is approximately 1 pg/ml of incubation mixture, corresponding to roughly 0.25 {mu}U/ml of serum at the serum dilutions used. In a formal comparative study, the method has been shown to be more sensitive, precise and accurate than other methods relying on double antibody or chromato-electrophoietic separation. The relevance of such factors as high specific activity labelled hormone to the attainment of high sensitivity is discussed. (author)

Autoantibody profiling in APS.

Science.gov (United States)

Roggenbuck, D; Somma, V; Schierack, P; Borghi, M O; Meroni, P L

2014-10-01

The international consensus for the classification of antiphospholipid syndrome (APS) requires clinical and laboratory criteria to be considered at an equal level for diagnosing APS. Thus, detection of antiphospholipid antibodies (aPL) being a hallmark of APS has been the object of intensive investigation over the past 40 years. However, appropriate detection of aPL still remains a laboratory challenge due to their heterogeneity comprising autoantibodies reactive to different phospholipid-binding plasma proteins, such as beta-2 glycoprotein I (β2GPI) and prothrombin. The relevance of aPL interacting with phospholipids other than cardiolipin (CL, diphosphatidylglycerol), such as phosphatidylserine (PS), remains elusive with regard to the diagnosis of APS. Recently, the concept of aPL profiling has been introduced to assess the risk of thrombotic complications in patients with APS. New assay techniques, apart from enzyme-linked immunosorbent assays (ELISAs) recommended by the international consensus for the classification of APS, have been proposed for multiplexing of aPL testing. Line immunoassays (LIAs) employing a novel hydrophobic solid phase for the simultaneous detection of different aPL seem to be an intriguing alternative. We evaluated a novel multiplex LIA employing a hydrophobic membrane coated with different phospholipid (PL)-binding proteins or PLs. The performance characteristics of this new multiplexing assay technique demonstrated its usefulness for aPL profiling. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

Autoantibodies in cryptogenic fibrosing alveolitis

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du Bois Ron

2001-02-01

Full Text Available Abstract The pathogenesis of cryptogenic fibrosing alveolitis (CFA involves injury, an immune/inflammatory response and fibrosis. The cause of the injury is unknown, but the identification of serum autoantibodies makes an autoimmune aetiology attractive. The core study on which this commentary is based used novel cloning and serum screening technologies in order to identify new public and private autoantibodies in sera from 12 patients with CFA. Largely negative conclusions were drawn from that study. However, we suggest that the prevalence of autoantibodies may have been underestimated, that the study was timely and that this approach is worth pursuing further.

Analytical and clinical performance of thyroglobulin autoantibody assays in thyroid cancer follow-up.

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Katrangi, Waddah; Grebe, Stephan K G; Algeciras-Schimnich, Alicia

2017-10-26

While thyroglobulin autoantibodies (TgAb) can result in false low serum thyroglobulin (Tg) immunoassay (IA) measurements, they might also be indicators of disease persistence/recurrence. Hence, accurate TgAb measurement, in addition to Tg quantification, is crucial for thyroid cancer monitoring. We compared the analytical and clinical performance of four commonly used TgAb IAs. We measured Tg by mass spectrometry (Tg-MS) and by four pairs of Tg and TgAb IAs (Beckman, Roche, Siemens, Thermo) in 576 samples. Limit of quantitation (LOQ) and manufacturers' upper reference interval cut-off (URI) were used for comparisons. Clinical performance was assessed by receiving operator characteristics (ROC) curve analysis. Quantitative and qualitative agreement between TgAb-IAs was moderate with R2 of 0.20-0.70 and κ from 0.41-0.66 using LOQ and 0.47-0.71 using URI. In samples with TgAb interference, detection rates of TgAb were similar using LOQ and URI for Beckman, Siemens, and Thermo, but much lower for the Roche TgAb-IA when the URI was used. In TgAb positive cases, the ROC areas under the curve (AUC) for the TgAb-IAs were 0.59 (Beckman), 0.62 (Siemens), 0.59 (Roche), and 0.59 (Thermo), similar to ROC AUCs achieved with Tg. Combining Tg and TgAb measurements improved the ROC AUCs compared to Tg or TgAb alone. TgAb-IAs show significant qualitative and quantitative differences. For 2 of the 4 TgAb-IAs, using the LOQ improves the detection of interfering TgAbs. All assays showed suboptimal clinical performance when used as surrogate markers of disease, with modest improvements when Tg and TgAb were combined.

The Role of Pathogenic Autoantibodies in Autoimmunity

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Merrill J. Rowley

2015-11-01

Full Text Available The serological presence of autoantibodies is diagnostic of autoimmunity, and these autoantibodies may be present for many years before the presentation of autoimmune disease (AID. Although a pathogenic role has been demonstrated for various autoantibodies reactive with cell surface and extracellular autoantigens, studies using monoclonal antibodies (mAb show not all antibodies in the polyclonal response are pathogenic. Differences depend on Fab-mediated diversity in epitope specificity, Fc-mediated effects based on immunoglobulin (Ig class and subclass, activation of complement, and the milieu in which the reaction occurs. These autoantibodies often occur in organ-specific AID and this review illustrates their pathogenic and highly specific effects. The role of autoantibodies associated with intracellular antigens is less clear. In vitro they may inhibit or adversely affect well-defined intracellular biochemical pathways, yet, in vivo they are separated from their autoantigens by multiple cellular barriers. Recent evidence that Ig can traverse cell membranes, interact with intracellular proteins, and induce apoptosis has provided new evidence for a pathogenic role for such autoantibodies. An understanding of how autoantibodies behave in the polyclonal response and their role in pathogenesis of AID may help identify populations of culprit B-cells and selection of treatments that suppress or eliminate them.

Autoantibodies in systemic sclerosis: Unanswered questions

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CRISTIANE eKAYSER

2015-04-01

Full Text Available Systemic sclerosis (SSc is an autoimmune disease characterized by vascular abnormalities, and cutaneous and visceral fibrosis. Serum autoantibodies directed to multiple intracellular antigens are present in more than 95% of patients and are considered a hallmark of SSc. They are helpful biomarkers for the early diagnosis of SSc and are associated with distinctive clinical manifestations. With the advent of more sensitive, multiplexed immunoassays, new and old questions about the relevance of autoantibodies in SSc are emerging. In this review we discuss the clinical relevance of autoantibodies in SSc emphasizing the more recently published data. Moreover, we will summarize recent advances regarding the stability of SSc autoantibodies over the course of disease, whether they are mutually exclusive and their potential roles in the disease pathogenesis.

Maternal celiac disease autoantibodies bind directly to syncytiotrophoblast and inhibit placental tissue transglutaminase activity

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Robinson Nicola J

2009-02-01

Full Text Available Abstract Background Celiac disease (CD occurs in as many as 1 in 80 pregnant women and is associated with poor pregnancy outcome, but it is not known if this is an effect on maternal nutrient absorption or, alternatively, if the placenta is an autoimmune target. The major autoantigen, tissue transglutaminase (tTG, has previously been shown to be present in the maternal-facing syncytiotrophoblast plasma membrane of the placenta. Methods ELISA was used to demonstrate the presence of antibodies to tissue transglutaminase in a panel of CD sera. Immunohistochemistry was used to evaluate the binding of IgA autoantibodies from CD serum to term placenta. In addition, novel direct binding and activity assays were developed to mimic the in vivo exposure of the villous placenta to maternal autoantibody. Results and Discussion CD IgA autoantibodies located to the syncytial surface of the placenta significantly more than IgA antibodies in control sera (P Conclusion These data indicate that direct immune effects in untreated CD women may compromise placental function.

Insulin receptor degradation is accelerated in cultured lymphocytes from patients with genetic syndromes of extreme insulin resistance

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McElduff, A.; Hedo, J.A.; Taylor, S.I.; Roth, J.; Gorden, P.

1984-01-01

The insulin receptor degradation rate was examined in B lymphocytes that were obtained from peripheral blood of normal subjects and patients with several syndromes of extreme insulin resistance. The insulin receptors were surface labeled using Na 125 I/lactoperoxidase and the cells were returned to incubate in growth media. After varying periods of incubation, aliquots of cells were solubilized and the cell content of labeled receptor subunits were measured by immunoprecipitation with anti-receptor antibodies and NaDodSO4/polyacrylamide gel electrophoresis. In cell lines from four patients in whom the number of insulin receptors was reduced by greater than 90%, the rate of receptor loss was greater than normal (t1/2 equals 3.8 +/- 0.9 h vs. 6.5 +/- 1.2 h; mean +/- SD, P less than 0.01). However, a similar acceleration in receptor degradation was seen in cells from five patients with extreme insulin resistance but low-normal insulin receptor concentration (t1/2 equals 4.4 +/- 0.9 h). Thus, all the patients with genetic syndromes of insulin resistance had accelerated receptor degradation, regardless of their receptor concentration. By contrast, insulin receptors on cultured lymphocytes that were obtained from patients with extreme insulin resistance secondary to autoantibodies to the insulin receptor had normal receptor degradation (t1/2 equals 6.1 +/- 1.9 h). We conclude that (a) accelerated insulin receptor degradation is an additional feature of cells from patients with genetic forms of insulin resistance; (b) that accelerated insulin receptor degradation may explain the low-normal receptor concentrations that were seen in some patients with extreme insulin resistance; and (c) that accelerated degradation does not explain the decreased receptor concentration in patients with very low insulin receptor binding and, therefore, by inference, a defect in receptor synthesis must be present in this subgroup

Simplified approaches for the development of an ELISA to detect circulating autoantibodies to p53 in cancer patients

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Tayapiwatana Chatchai

2008-02-01

Full Text Available Abstract Background The recognition that human tumors stimulate the production of autoantibodies has initiated the use of this immune response as serological markers for the early diagnosis and management of cancer. The enzyme-linked immunosorbent assay (ELISA is the most common method used in detecting autoantibodies, which involves coating the microtiter plate with the tumor associated antigen (TAA of interest and allowing serum antibodies to bind. The patient's sample is directly in contact with the coating antigen so the protein used for coating must be pure to avoid non-specific binding. In this study, a simplified method to selectively and specifically immobilize TAAs onto microtiter plates in order to detect circulating autoantibodies in cancer patients without prior purification process was described. Wild type full-length p53 protein was produced in fusion with biotin carboxyl carrier peptide (BCCP or hexahistidine [(His6] using pAK400 and pET15b(+ vectors, respectively. The recombinant p53 fusion protein produced was then subjected to react with either a commercial p53 monoclonal antibody (mAb or sera from lung cancer patients and healthy volunteers in an enzyme-linked immunosorbent assay (ELISA format. Results Both of the immobilized p53 fusion proteins as well as the purified (His6-p53 fusion protein had a similar dose response of detection to a commercial p53 mAb (DO7. When the biotinylated p53-BCCP fusion protein was used as an antigen to detect p53 autoantibodies in clinical samples, the result showed that human serum reacted strongly to avidin-coated microwell even in the absence of the biotinylated p53-BCCP fusion protein, thus compromised its ability to differentiate weakly positive sera from those that were negative. In contrast, the (His6-p53 protein immobilized directly onto Ni+ coated microplate was able to identify the p53 autoantibody positive serum. In addition, its reactivity to clinical serum samples highly correlated

Myositis specific autoantibodies: changing insights in pathophysiology and clinical associations.

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Hengstman, G.J.D.; Engelen, B.G.M. van; Venrooij, W.J.W. van

2004-01-01

PURPOSE OF REVIEW: Defined autoantibodies are found in about half of the patients with myositis. Traditionally, these autoantibodies have been divided into myositis specific autoantibodies (MSAs) and myositis associated autoantibodies. Several studies have shown that MSAs are associated with

Detection and Characterization of Autoantibodies to Neuronal Cell-Surface Antigens in the Central Nervous System

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Marleen eVan Coevorden-Hameete

2016-05-01

Full Text Available Autoimmune encephalitis (AIE is a group of disorders in which autoantibodies directed at antigens located on the plasma membrane of neurons induce severe neurological symptoms. In contrast to classical paraneoplastic disorders, AIE patients respond well to immunotherapy. The detection of neuronal surface autoantibodies in patients’ serum or CSF therefore has serious consequences for the patients’ treatment and follow-up and requires the availability of sensitive and specific diagnostic tests. This mini-review provides a guideline for both diagnostic and research laboratories that work on the detection of known surface autoantibodies and/or the identification of novel surface antigens. We discuss the strengths and pitfalls of different techniques for anti-neuronal antibody detection: 1 Immunohistochemistry and immunofluorescence on rat/ primate brain sections, 2 Immunocytochemistry of living cultured hippocampal neurons, 3 Cell Based Assay (CBA. In addition, we discuss the use of immunoprecipitation and mass spectrometry analysis for the detection of novel neuronal surface antigens, which is a crucial step in further disease classification and the development of novel CBAs.

An immunochemical method for the quantitation of insulin antibodies

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Reeves, W.G.; Kelly, U.

1980-01-01

A 125 I-labelled insulin binding assay is described in which IgG antibody is precipitated by the addition of an optimal concentration of second antibody. Other features include the removal of unlabelled insulin from test sera prior to assay and the use of 22 Na as a volume marker. This approach overcomes problems associated with previous assays for insulin antibodies. Clear differences are seen in the IgG insulin binding capacity (IBC) of sera from patients with insulin resistance and injection site lipo-atrophy when compared with insulin-treated diabetics who lack such complications. The precision and flexibility of this technique make it particularly suitable for studies of the immune response to different species and forms of insulin. (Auth.)

Origins of anti-DNA autoantibodies

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Schwartz, R.S.

1985-01-01

The direction of research in autoimmunity was strongly influenced by three notable discoveries made more than 25 year ago: anti-DNA anti-bodies in lupus serum, the immunofluorescent antinuclar antibody test and the NZB mouse. Now another turning point has been reached for three new reasons: the discovery of the hybridoma technic, advances in cellular immunology and the use of molecular biology to solve immunological problems. These developments have motivated fresh approaches to questions about the origins and pathogenic mechanisms of autoantibodies. Systemic lupus erythematosus (SLE) has a conspicuous position in the field of autoimmunity for several reasons. Its diverse manifestations have attracted a correspondingly diverse group of investigators whose interests range from molecular biology to therapeutic trials; superb models of the disease occur spontaneously in animals; and the extensive variety of autoantibodies in SLE provides an abundance of investigative reagents. An explanation of the origins of these autoantibodies is one of the major goals of research in the disease. The autoantibodies that bind to DNA are of central interest. They occur in almost all patients with active SLE, they often fluctuate with its clinical activity, and they participate in forming its lesions

An uncommon cause of hypoglycemia: insulin autoimmune syndrome.

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Savas-Erdeve, Senay; Yılmaz Agladioglu, Sebahat; Onder, Asan; Peltek Kendirci, Havva Nur; Bas, Veysel Nijat; Sagsak, Elif; Cetinkaya, Semra; Aycan, Zehra

2014-01-01

Insulin autoimmune syndrome (IAS) is a condition characterized by hypoglycemia associated with the presence of autoantibodies to insulin in patients who have not been injected with insulin. A female patient (aged 16 years and 3 months) presented with the complaint of being overweight. Physical examination revealed a body weight of 78.2 kg (+2.6 SD) and a height of 167 cm (+0.73 SD). While the patient's fasting blood glucose level was found to be 40 mg/dl, blood ketone was negative and the serum insulin level was determined as 379 mIU/ml. The patient was diagnosed with hyperinsulinemic hypoglycemia. Abdominal ultrasound, pancreas MRI and endoscopic ultrasound were normal. The daily blood glucose profile revealed postprandial hyperglycemia and reactive hypoglycemia in addition to fasting hypoglycemia. The results of anti-insulin antibody measurements were as high as 41.8% (normal range 0-7%). A 1,600-calorie diet containing 40% carbohydrate and divided into 6 meals a day was given to the patient. Simple sugars were excluded from the diet. Hypoglycemic episodes were not observed, but during 2 years of observation, serum levels of insulin and anti-insulin antibodies remained elevated. In all hyperinsulinemic hypoglycemia cases, IAS should be considered in the differential diagnosis and insulin antibody measurements should be carried out. © 2014 S. Karger AG, Basel.

Isotypes and antigenic profiles of pemphigus foliaceus and pemphigus vulgaris autoantibodies.

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Hacker, Mary K; Janson, Marleen; Fairley, Janet A; Lin, Mong-Shang

2002-10-01

In this study we systematically characterized isotype profiles and antigenic and tissue specificity of antidesmoglein autoantibodies from patients with pemphigus foliaceus (PF) and pemphigus vulgaris (PV) using enzyme-linked immunoabsorbent assays (ELISA), indirect immunofluorescence (IIF) staining, and immunoblotting (IB). In PF, we found that IgG1 antidesmoglein-1 (Dsg1) reacts with a linear epitope(s) on the ectodomain of Dsg1, while its IgG4 counterpart recognizes a conformational epitope(s). These two subclasses of anti-Dsg1 are both capable of recognizing tissues from monkey esophagus and adult human skin, but IgG1 is not able to react with mouse skin, which may explain why this isotype of anti-Dsg1 failed to induce PF-like lesions in the passive transfer animal model. In mucosal PV patients, we found that both IgG1 and IgG4 only recognized monkey esophagus tissue by IIF, except in one patient, indicating that these antibodies react with a unique conformational epitope(s) that is present in mucosal but not skin tissue. In generalized PV, IgG1 anti-Dsg3 autoantibodies appeared to recognize a linear epitope(s) on the Dsg3 ectodomain. In contrast, IgG4 anti-Dsg3 antibodies recognized both linear and conformational epitopes on the Dsg3 molecule. Interestingly, the IgG1 anti-Dsg3 antibodies failed to react with human and mouse skin tissues, suggesting that this subclass of autoantibodies may not play an essential role in the development of PV suprabasilar lesions. In summary, we conclude that this study further elucidates the pathological mechanisms of PF and PV autoantibodies by revealing their distinct isotype and antigenic profiles. This information may help us to better understand the autoimmune mechanisms underlying the development of pemphigus.

The influence of maternal islet beta-cell autoantibodies in conjunction with gestational hyperglycemia on neonatal outcomes.

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Zhe Li

Full Text Available To determine the predictive value of the presence of maternal islet beta-cell autoantibodies with respect to neonatal outcomes.A total of 311 pregnant women with abnormal 75 g oral glucose tolerance test (OGTT results were enrolled in this study. Maternal glutamic acid decarboxylase autoantibodies (GADA, islet cell autoantibodies (ICA and insulin autoantibodies (IAA were tested in fasting blood both on the day following the routine OGTT and before delivery. The birth weight, Apgar score, blood glucose and outcomes of each neonate were later evaluated and recorded.1. In this study, 33.9% of the pregnant women with gestational hyperglycemia had detectable levels of one or more types of anti-islet cell antibodies in the third trimester. The proportion of women who produced GADA and/or ICA was significantly higher in the group of women with gestational hyperglycemia than in the control group (P<0.05. The groups similarly differed in the proportion of women who tested positive for any anti-islet cell antibody (P<0.05. 2. Of the patients in our study, those who produced GADA exhibited an increase in uterine and umbilical arterial pulsatility indexes (PIs during the third trimesters compared with the control group (P˂0.05. Additionally, an increased frequency of fetal growth restriction (FGR was observed in the infants of women who produced IAA during pregnancy compared with those without autoantibodies (P˂0.05. 3. The rate of newborn admission to the neonatal intensive care unit (NICU was significantly associated with the presence of maternal ICA during the third trimester (OR, 6.36; 95% CI, 1.22-33.26. 4. The incidence of neonatal asphyxia was associated with the presence of maternal GADA in both the second (OR, 10.44; 95% CI, 1.46-74.92 and the third (OR, 8.33; 95% CI, 1.45-47.82 trimesters.Approximately one-third of the women with gestational hyperglycemia produced anti-islet cell antibodies. The incidence of FGR was higher in women with

Serum tumor-associated autoantibodies as diagnostic biomarkers for lung cancer: A systematic review and meta-analysis.

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Zhen-Ming Tang

Full Text Available We performed a comprehensive review and meta-analysis to evaluate the diagnostic values of serum single and multiplex tumor-associated autoantibodies (TAAbs in patients with lung cancer (LC.We searched the MEDLINE and EMBASE databases for relevant studies investigating serum TAAbs for the diagnosis of LC. The primary outcomes included sensitivity, specificity and accuracy of the test.The systematic review and meta-analysis included 31 articles with single autoantibody and 39 with multiplex autoantibodies. Enzyme-linked immunosorbent assay (ELISA was the most common detection method. For the diagnosis of patients with all stages and early-stage LC, different single or combinations of TAAbs demonstrated different diagnostic values. Although individual TAAbs showed low diagnostic sensitivity, the combination of multiplex autoantibodies offered relatively high sensitivity. For the meta-analysis of a same panel of autoantibodies in patients at all stages of LC, the pooled results of the panel of 6 TAAbs (p53, NY-ESO-1, CAGE, GBU4-5, Annexin 1 and SOX2 were: sensitivity 38% (95% CI 0.35-0.40, specificity 89% (95% CI 0.86-0.91, diagnostic accuracy 65.9% (range 62.5-81.8%, AUC 0.52 (0.48-0.57, while the summary estimates of 7 TAAbs (p53, CAGE, NY-ESO-1, GBU4-5, SOX2, MAGE A4 and Hu-D were: sensitivity 47% (95% CI 0.34-0.60, specificity 90% (95% CI 0.89-0.92, diagnostic accuracy 78.4% (range 67.5-88.8%, AUC 0.90 (0.87-0.93. For the meta-analysis of the same panel of autoantibodies in patients at early-stage of LC, the sensitivities of both panels of 7 TAAbs and 6 TAAbs were 40% and 29.7%, while their specificities were 91% and 87%, respectively.Serum single or combinations of multiplex autoantibodies can be used as a tool for the diagnosis of LC patients at all stages or early-stage, but the combination of multiplex autoantibodies shows a higher detection capacity; the diagnostic value of the panel of 7 TAAbs is higher than the panel of 6 TAAbs, which

Phenotypic and environmental factors associated with elevated autoantibodies at clinical onset of paediatric type 1 diabetes mellitus.

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Ponsonby, Anne-Louise; Pezic, Angela; Cameron, Fergus J; Rodda, Christine; Ellis, Justine A; Kemp, Andrew S; Carlin, John; Dwyer, Terence

2012-01-01

To examine possible determinants of autoantibody levels at type 1 diabetes mellitus (T1DM) onset. We assessed levels of glutamic acid decarboxylase 65 islet cell antigen (GADA) and anti-insulin antibodies (IAA) in 247 incident T1DM cases presenting <15 years of age in Melbourne from 1st March 2008 to 30th June 2010. 58.9% (142/241) of cases were GADA seropositive and 42.3% (94/222) were IAA seropositive. Factors associated with elevated IAA antibodies included younger age and red hair phenotype. Factors associated with elevated GAD antibodies included lower birthweight and recent eczema. Intriguingly, low recent or past sun exposure was only associated with elevated GADA levels among children presenting at age <5 years, not older (difference in effect, p<0.05 for 4 of 5 associations). These findings show that environmental and phenotypic factors are associated with autoantibody levels at time of presentation for T1DM. We recommend such environmental and phenoytypic factors should be examined in further detail.

Pituitary autoantibodies in endocrine disorders

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Bensing, Sophie

2005-01-01

Autoimmune endocrine disorders are characterised by the development of autoantibodies to specific autoantigens in the target organs. Lymphocytic hypophysitis (LyH) is a disease characterised by inflammation of the pituitary gland, often resulting in hypopituitarism. The aetiology of LyH is considered to be autoimmune. However, only a few pituitary autoantigens have so far been identified. Reliable autoantibody markers are requested in the diagnostic procedure of LyH to avoid...

Autoantibody response against NALP5/MATER in primary ovarian insufficiency and in autoimmune Addison's disease.

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Brozzetti, Annalisa; Alimohammadi, Mohammad; Morelli, Silvia; Minarelli, Viviana; Hallgren, Åsa; Giordano, Roberta; De Bellis, Annamaria; Perniola, Roberto; Kämpe, Olle; Falorni, Alberto

2015-05-01

NACHT leucine-rich-repeat protein 5 (NALP5)/maternal antigen that embryo requires (MATER) is an autoantigen in hypoparathyroidism associated with autoimmune polyendocrine syndrome type 1 (APS1) but is also expressed in the ovary. Mater is an autoantigen in experimental autoimmune oophoritis. The objectives of the study were to determine the frequency of NALP5/MATER autoantibodies (NALP5/MATER-Ab) in women with premature ovarian insufficiency (POI) and in patients with autoimmune Addison's disease (AAD) and to evaluate whether inhibin chains are a target for autoantibodies in POI. Autoantibodies against NALP5/MATER and inhibin chains-α and -βA were determined by radiobinding assays in 172 patients with AAD without clinical signs of gonadal insufficiency, 41 women with both AAD and autoimmune POI [steroidogenic cell autoimmune POI (SCA-POI)], 119 women with idiopathic POI, 19 patients with APS1, and 211 healthy control subjects. NALP5/MATER-Ab were detected in 11 of 19 (58%) sera from APS1 patients, 12 of 172 (7%) AAD sera, 5 of 41 (12%) SCA-POI sera, 0 of 119 idiopathic POI sera and 1 of 211 healthy control sera (P < .001). None of 160 POI sera, including 41 sera from women with SCA-POI and 119 women with idiopathic POI, and none of 211 healthy control sera were positive for inhibin chain-α/βA autoantibodies. NALP5/MATER-Ab are associated with hypoparathyroidism in APS1 but are present also in patients with AAD and in women with SCA-POI without hypoparathyroidism. Inhibin chains do not appear to be likely candidate targets of autoantibodies in human POI.

Antineutrophil cytoplasmic autoantibody-associated small-vessel vasculitis

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Kallenberg, Cees G. M.

Purpose of reviews This review focuses on recent advance in the diagnosis pathogenesis and treatment of antineutrophil cytoplasmic autoantibody-associated small-vessel vasculitis. Recent findings Antineutrophil cytoplasmic autoantibodies are closely associated with Wegener's granulomatosis and

Identification of novel autoantibodies for detection of malignant mesothelioma.

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Xufei Zhang

Full Text Available The malignant mesothelioma (MM survival rate has been hampered by the lack of efficient and accurate early detection methods. The immune system may detect the early changes of tumor progression by responding with tumor-associated autoantibody production. Hence, in this study, we translated the humoral immune response to cancer proteins into a potential blood test for MM.A T7 phage MM cDNA library was constructed using MM tumor tissues and biopanned for tumor-associated antigens (TAAs using pooled MM patient and normal serum samples. About 1008 individual phage TAA clones from the biopanned library were subjected to protein microarray construction and tested with 53 MM and 52 control serum samples as a training group. Nine candidate autoantibody markers were selected from the training group using Tclass system and logistic regression statistical analysis, which achieved 94.3% sensitivity and 90.4% specificity with an AUC value of 0.89 in receiver operating characteristic analysis. The classifier was further evaluated with 50 patient and 50 normal serum samples as an independent blind validation, and the sensitivity of 86.0% and the specificity of 86.0% were obtained with an AUC of 0.82. Sequencing and BLASTN analysis of the classifier revealed that five of these nine candidate markers were found to have strong homology to cancer related proteins (PDIA6, MEG3, SDCCAG3, IGHG3, IGHG1.Our results indicated that using a panel of 9 autoantibody markers presented a promising accuracy for MM detection. Although the results need further validation in high-risk groups, they provided the potentials in developing a serum-based assay for MM diagnosis.

Saffold Virus, a Human Cardiovirus, and Risk of Persistent Islet Autoantibodies in the Longitudinal Birth Cohort Study MIDIA.

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German Tapia

Full Text Available The aim of this study was to describe the frequency and distribution of Saffold virus in longitudinal stool samples from children, and test for association with development of persistent autoantibodies predictive of type 1 diabetes. A cohort of Norwegian children carrying the HLA genotype associated with highest risk of type 1 diabetes ("DR4-DQ8/DR3-DQ2" was followed with monthly stool samples from 3 to 35 months of age. Blood samples were tested for autoantibodies to insulin, glutamic acid decarboxylase65 and Islet Antigen-2. 2077 stool samples from 27 children with ≥ 2 repeatedly positive islet autoantibodies (cases, and 53 matched controls were analysed for Saffold virus genomic RNA by semi-quantitative real-time reverse transcriptase PCR. Saffold virus was found in 53 of 2077 (2.6% samples, with similar proportions between cases (2.5% and controls (2.6%. The probability of being infected by 3 years of age was 28% (95% CI 0.18-0.40. Viral quantities ranged from <1 to almost 105 copies/μl. Estimated odds ratio between islet autoimmunity and infection episodes prior to seroconversion was 1.98 (95% CI: 0.57-6.91, p = 0.29. Saffold virus had no statistically significant association with islet autoimmunity.

Multiplex autoantibody detection for autoimmune liver diseases and autoimmune gastritis.

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Vanderlocht, Joris; van der Cruys, Mart; Stals, Frans; Bakker-Jonges, Liesbeth; Damoiseaux, Jan

2017-09-01

Autoantibody detection for autoimmune hepatitis (AIH), primary biliary cirrhosis (PBC) and autoimmune gastritis (AIG) is traditionally performed by IIF on a combination of tissues. Multiplex line/dot blots (LIA/DIA) offer multiple advantages, i.e. automation, objective reading, no interfering reactivities, no coincidental findings. In the current study we evaluated automated DIA (D-Tek) for detecting autoantibodies related to autoimmune diseases of the gastrointestinal tract. We tested samples of the Dutch EQC program and compared the results with the consensus of the participating labs. For the autoimmune liver diseases and AIG, respectively, 64 and 36 samples were tested. For anti-mitochondrial and anti-smooth muscle antibodies a concordance rate of 97% and 88% was observed, respectively. The concordance rate for anti-parietal cell antibodies was 92% when samples without EQC consensus (n=15) were excluded. For antibodies against intrinsic factor a concordance of 96% was observed. For all these antibodies discrepancies were identified that relate to the different test characteristics and the preponderance of IIF utilizing labs in the EQC program. In conclusion, we observed good agreement of the tested DIA blots with the consensus results of the Dutch EQC program. Taken together with the logistic advantages these blots are a good alternative for autoantibody detection in the respective diseases. A large prospective multicenter study is warranted to position these novel tests further in the whole spectrum of assays for the detection of these antibodies in a routine autoimmune laboratory. Copyright © 2017 Elsevier B.V. All rights reserved.

Bronchus-associated lymphoid tissue in pulmonary hypertension produces pathologic autoantibodies.

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Colvin, Kelley L; Cripe, Patrick J; Ivy, D Dunbar; Stenmark, Kurt R; Yeager, Michael E

2013-11-01

Autoimmunity has long been associated with pulmonary hypertension. Bronchus-associated lymphoid tissue plays important roles in antigen sampling and self-tolerance during infection and inflammation. We reasoned that activated bronchus-associated lymphoid tissue would be evident in rats with pulmonary hypertension, and that loss of self-tolerance would result in production of pathologic autoantibodies that drive vascular remodeling. We used animal models, histology, and gene expression assays to evaluate the role of bronchus-associated lymphoid tissue in pulmonary hypertension. Bronchus-associated lymphoid tissue was more numerous, larger, and more active in pulmonary hypertension compared with control animals. We found dendritic cells in and around lymphoid tissue, which were composed of CD3(+) T cells over a core of CD45RA(+) B cells. Antirat IgG and plasma from rats with pulmonary hypertension decorated B cells in lymphoid tissue, resistance vessels, and adventitia of large vessels. Lymphoid tissue in diseased rats was vascularized by aquaporin-1(+) high endothelial venules and vascular cell adhesion molecule-positive vessels. Autoantibodies are produced in bronchus-associated lymphoid tissue and, when bound to pulmonary adventitial fibroblasts, change their phenotype to one that may promote inflammation. Passive transfer of autoantibodies into rats caused pulmonary vascular remodeling and pulmonary hypertension. Diminution of lymphoid tissue reversed pulmonary hypertension, whereas immunologic blockade of CCR7 worsened pulmonary hypertension and hastened its onset. Bronchus-associated lymphoid tissue expands in pulmonary hypertension and is autoimmunologically active. Loss of self-tolerance contributes to pulmonary vascular remodeling and pulmonary hypertension. Lymphoid tissue-directed therapies may be beneficial in treating pulmonary hypertension.

Production of Autoantibodies by Murine B-1a Cells Stimulated with Helicobacter pylori Urease through Toll-Like Receptor 2 Signaling ▿ †

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Kobayashi, Fumiko; Watanabe, Eri; Nakagawa, Yohko; Yamanishi, Shingo; Norose, Yoshihiko; Fukunaga, Yoshitaka; Takahashi, Hidemi

2011-01-01

Helicobacter pylori infection is associated with several autoimmune diseases, in which autoantibody-producing B cells must be activated. Among these B cells, CD5-positive B-1a cells from BALB/c mice were confirmed to secrete autoantibodies when cocultured with purified H. pylori urease in the absence of T cells. To determine the mechanisms for autoantibody production, CD5-positive B-1a cells were sorted from murine spleen cells and stimulated with either purified H. pylori urease or H. pylori coated onto plates (referred to hereafter as plate-coated H. pylori), and autoantibody production was measured by enzyme-linked immunosorbent assay (ELISA). Complete urease was not secreted from H. pylori but was visually expressed over the bacterium-like endotoxin. Urease-positive plated-coated H. pylori stimulated B-1a cells to produce autoantibodies, although urease-deficient isotype-matched H. pylori did not. Autoantibody secretion by B-1a cells was inhibited when bacteria were pretreated with anti-H. pylori urease-specific antibody having neutralizing ability against urease enzymatic activity but not with anti-H. pylori urease-specific antibody without neutralizing capacity. The B-1a cells externally express various Toll-like receptors (TLRs): TLR1, TLR2, TLR4, and TLR6. Among the TLRs, blocking of TLR2 on B-1a cells with a specific monoclonal antibody (MAb), T2.5, inhibited autoantibody secretion when B-1a cells were stimulated with plate-coated H. pylori or H. pylori urease. Moreover, B-1a cells from TLR2-knockout mice did not produce those autoantibodies. The present study provides evidence that functional urease expressed on the surface of H. pylori will directly stimulate B-1a cells via innate TLR2 to produce various autoantibodies and may induce autoimmune disorders. PMID:21947775

Study of NSILA-s (nonsuppressible insulin-like activity soluble in acid ethanol) by a new radio-receptor assay

International Nuclear Information System (INIS)

Megyeri, K.

1977-01-01

The insulin-like activity nonsuppressible with insulin-antibodies (NSILA) accounts for 90% of the insulin activity of the blood plasma. A peptid, soluble in acid ethanol, was purified (NSILA-s) and specific NSILA-s receptors were found on the plasma membrane of liver cells. The specificity, kinetics, affinity and pH-optimum of NSILA-s receptors significantly differed from those of insulin-receptors. A new, highly specific radio-receptor assay was developed, applying 125 I NSILA-s and liver cell membranes or lymphocytes. By this means the NSILA-s concentration of blood plasma was determined under normal and pathological (hypoglycaemizing tumours, hypopituritarism, acromegaly, anorexia nervosa, etc.) conditions. It is concluded that, 90% of the NSILA-s concentration of blood plasma is bound. In cases of hypoglycaemizing tumours increased NSILA-s activity was demonstrated both in blood serum and in the extracts of the tumour-tissue. Pharmacological doses of growth hormon (GH) increased plasma NSILA-s concentration, however, in the case of stimulation- and inhibition-tests carried out in normal patients, no unambiguous relationship could be demonstrated between plasma GH- and NSILA-s-levels. (L.E.)

The relationship between BMI and insulin resistance and progression from single to multiple autoantibody positivity and type 1 diabetes among TrialNet Pathway to Prevention participants.

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Meah, Farah A; DiMeglio, Linda A; Greenbaum, Carla J; Blum, Janice S; Sosenko, Jay M; Pugliese, Alberto; Geyer, Susan; Xu, Ping; Evans-Molina, Carmella

2016-06-01

The incidence of type 1 diabetes is increasing at a rate of 3-5% per year. Genetics cannot fully account for this trend, suggesting an influence of environmental factors. The accelerator hypothesis proposes an effect of metabolic factors on type 1 diabetes risk. To test this in the TrialNet Pathway to Prevention (PTP) cohort, we analysed the influence of BMI, weight status and insulin resistance on progression from single to multiple islet autoantibodies (Aab) and progression from normoglycaemia to diabetes. HOMA1-IR was used to estimate insulin resistance in Aab-positive PTP participants. Cox proportional hazards models were used to evaluate the effects of BMI, BMI percentile (BMI%), weight status and HOMA1-IR on the progression of autoimmunity or the development of diabetes. Data from 1,310 single and 1,897 multiple Aab-positive PTP participants were included. We found no significant relationships between BMI, BMI%, weight status or HOMA1-IR and the progression from one to multiple Aabs. Similarly, among all Aab-positive participants, no significant relationships were found between BMI, weight status or HOMA1-IR and progression to diabetes. Diabetes risk was modestly increased with increasing BMI% among the entire cohort, in obese participants 13-20 years of age and with increasing HOMA1-IR in adult Aab-positive participants. Analysis of the accelerator hypothesis in the TrialNet PTP cohort does not suggest a broad influence of metabolic variables on diabetes risk. Efforts to identify other potentially modifiable environmental factors should continue.

Tumour auto-antibody screening: performance of protein microarrays using SEREX derived antigens

International Nuclear Information System (INIS)

Stempfer, René; Weinhäusel, Andreas; Syed, Parvez; Vierlinger, Klemens; Pichler, Rudolf; Meese, Eckart; Leidinger, Petra; Ludwig, Nicole; Kriegner, Albert; Nöhammer, Christa

2010-01-01

The simplicity and potential of minimal invasive testing using serum from patients make auto-antibody based biomarkers a very promising tool for use in diagnostics of cancer and auto-immune disease. Although several methods exist for elucidating candidate-protein markers, immobilizing these onto membranes and generating so called macroarrays is of limited use for marker validation. Especially when several hundred samples have to be analysed, microarrays could serve as a good alternative since processing macro membranes is cumbersome and reproducibility of results is moderate. Candidate markers identified by SEREX (serological identification of antigens by recombinant expression cloning) screenings of brain and lung tumour were used for macroarray and microarray production. For microarray production recombinant proteins were expressed in E. coli by autoinduction and purified His-tag (histidine-tagged) proteins were then used for the production of protein microarrays. Protein arrays were hybridized with the serum samples from brain and lung tumour patients. Methods for the generation of microarrays were successfully established when using antigens derived from membrane-based selection. Signal patterns obtained by microarrays analysis of brain and lung tumour patients' sera were highly reproducible (R = 0.92-0.96). This provides the technical foundation for diagnostic applications on the basis of auto-antibody patterns. In this limited test set, the assay provided high reproducibility and a broad dynamic range to classify all brain and lung samples correctly. Protein microarray is an efficient means for auto-antibody-based detection when using SEREX-derived clones expressing antigenic proteins. Protein microarrays are preferred to macroarrays due to the easier handling and the high reproducibility of auto-antibody testing. Especially when using only a few microliters of patient samples protein microarrays are ideally suited for validation of auto-antibody

Autoantibodies to Posttranslational Modifications in Rheumatoid Arthritis

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Burska, Agata N.; Hunt, Laura; Strollo, Rocky; Ryan, Brent J.; Vital, Ed; Nissim, Ahuva; Winyard, Paul G.; Emery, Paul; Ponchel, Frederique

2014-01-01

Autoantibodies have been associated with human pathologies for a long time, particularly with autoimmune diseases (AIDs). Rheumatoid factor (RF) is known since the late 1930s to be associated with rheumatoid arthritis (RA). The discovery of anticitrullinated protein antibodies in the last century has changed this and other posttranslational modifications (PTM) relevant to RA have since been described. Such PTM introduce neoepitopes in proteins that can generate novel autoantibody specificities. The recent recognition of these novel specificities in RA provides a unique opportunity to understand human B-cell development in vivo. In this paper, we will review the three of the main classes of PTMs already associated with RA: citrullination, carbamylation, and oxidation. With the advancement of research methodologies it should be expected that other autoantibodies against PTM proteins could be discovered in patients with autoimmune diseases. Many of such autoantibodies may provide significant biomarker potential. PMID:24782594

Osteoprotegerin autoantibodies do not predict low bone mineral density in middle-aged women.

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Vaziri-Sani, Fariba; Brundin, Charlotte; Agardh, Daniel

2017-12-01

Autoantibodies against osteoprotegerin (OPG) have been associated with osteoporosis. The aim was to develop an immunoassay for OPG autoantibodies and test their diagnostic usefulness of identifying women general population with low bone mineral density. Included were 698 women at mean age 55.1 years (range 50.4-60.6) randomly selected from the general population. Measurement of wrist bone mineral density (g/cm 2 ) was performed of the non-dominant wrist by dual-energy X-ray absorptiometry (DXA). A T-score density. Measurements of OPG autoantibodies were carried by radiobinding assays. Cut-off levels for a positive value were determined from the deviation from normality in the distribution of 398 healthy blood donors representing the 99.7th percentile. Forty-five of the 698 (6.6%) women were IgG-OPG positive compared with 2 of 398 (0.5%) controls ( p  density between IgG-OPG positive (median 0.439 (range 0.315-0.547) g/cm 2 ) women and IgG-OPG negative (median 0.435 (range 0.176-0.652) g/cm 2 ) women ( p  = 0.3956). Furthermore, there was neither a correlation between IgG-OPG levels and bone mineral density (r s  = 0.1896; p  = 0.2068) nor T-score (r s  = 0.1889; p  = 0.2086). Diagnostic sensitivity and specificity of IgG-OPG for low bone mineral density were 5.7% and 92.9%, and positive and negative predictive values were 7.4% and 90.8%, respectively. Elevated OPG autoantibody levels do not predict low bone mineral density in middle-aged women selected from the general population.

Rheumatic Disease Autoantibodies in Autoimmune Liver Diseases.

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Utiyama, Shirley R R; Zenatti, Katiane B; Nóbrega, Heloisa A J; Soares, Juliana Z C; Skare, Thelma L; Matsubara, Caroline; Muzzilo, Dominique A; Nisihara, Renato M

2016-08-01

Autoimmune liver diseases (ALDs) are known to be associated with systemic autoimmune rheumatic diseases (SARDs) and their autoantibodies. We aimed to study the prevalence of SARDs and related autoantibodies, as well as their prognostic implications in a group of patients with ALDs. This was a cross-sectional study. Sixty patients with ALDs (38.3% with autoimmune hepatitis; 11.7% with primary biliary cirrhosis; 25% with primary sclerosing cholangitis and 25% with overlap syndrome) were studied for the presence of SARDs and their autoantibodies. There was autoimmune rheumatic disease in 20% of the studied sample. Systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA) were the commonest (11.6% and 5%, respectively). Antinuclear antibodies (ANAs) were present in 35% of the patients, followed by anti-Ro (20.0%); anti-nucleosome (18.3%); rheumatoid factor (10%) anti-CCP (8.3%); anti-RNP (8.3%); anti-ds-DNA (6.6%); anti-La (3.3%); anti-Sm (3.3%), anti-ribosomal P (3.3%). Anti-Ro (p = 0.0004), anti-La (p = 0.03), anti-RNP (p = 0.04) and anti-Sm (p = 0.03) were commonly found in patients with SARD, but not anti-DNA, anti-nucleosome and anti-ribosomal P. No differences were found in liver function tests regarding to the presence of autoantibodies. There was a high prevalence of SARD and their autoantibodies in ALD patients. Anti-Ro, anti-La, anti-RNP and anti-Sm positivity points to an association with systemic autoimmune rheumatic diseases. The presence of autoantibodies was not related to liver function tests.

Anti-LC1 autoantibodies in patients with chronic hepatitis C virus infection.

Science.gov (United States)

Béland, Kathie; Lapierre, Pascal; Marceau, Gabriel; Alvarez, Fernando

2004-03-01

Various autoantibodies have been reported in patients chronically infected by hepatitis C virus. 2% to 10% of theses patients have anti-liver-kidney microsome type 1 (anti-LKM1) autoantibodies. In type 2 autoimmune hepatitis, anti-LKM1 autoantibodies are frequently associated with anti-liver-cytosol type 1 (anti-LC1) autoantibodies. To determine the prevalence of anti-LC1 autoantibodies in a hepatitis C-positive population and characterize their reactivity. 146 patients suffering from liver diseases, of which 99 were chronically infected by hepatitis C virus, were tested by Western blotting and immunoprecipitation to detect and characterize anti-LC1 autoantibodies. 12% of this hepatitis C population had anti-LC1 autoantibodies. LC1 positivity by Western blotting was 30% of LC1+ sera. Epitopes were found throughout the protein but linear epitopes were situated in the 395-541 amino acid region of formiminotransferase cyclodeaminase. Three putative conformational epitopes were identified by phage display. Anti-LC1 autoantibodies are as prevalent as anti-LKM1 autoantibodies in patients infected with hepatitis C virus and their production is not dependent of anti-LKM1 autoantibodies formation. Autoantibody reactivity against the anti-LC1 antigen is different in hepatitis C than in type 2 autoimmune hepatitis. Anti-LC1 autoantibodies can now be regarded as a serological marker of autoimmunity in chronic hepatitis C infection.

Myositis specific autoantibodies; specificity and clinical applications.

NARCIS (Netherlands)

Hengstman, G.J.D.

2005-01-01

The sera of about half of the patients with myositis contain autoantibodies that are specific for this group of diseases compared to other inflammatory connective tissue disorders. In a recent study we showed that these myositis specific autoantibodies (MSAs) are also specific for myositis as

The Prevalence of Antithyroid Autoantibodies in Normal Korean Population*

Science.gov (United States)

Lee, Myung Shik; Lee, Dong Soo; Han, Jin Suk; Cho, Bo Youn; Koh, Chang Soon; Lee, Munho

1986-01-01

The prevalence of antithyroid autoantibodies and the relationship between the presence of autoantibodies and thyroid functions were studied in 848 apparently normal Korean adults with tanned red cell agglutination technique. Results are summarized as follows: 1) The prevalence of antimicrosimal antibody (MCHA) and antithyroglobulin antibody (TGHA) were 4.4% and 1.9% in 458 males, and 12.4% and 5.0% in 390 females, respectively. Both autoantibodies were more prevalent in female (pantithyroid autoantibody of high titer (⩾1:1002) was related to alteration of thyroid functions suggesting the existence of “subclinical autoimmune thyroiditis” state. PMID:15759373

Autoantibodies in chronic pancreatitis

DEFF Research Database (Denmark)

Rumessen, J J; Marner, B; Pedersen, N T

1985-01-01

In 60 consecutive patients clinically suspected of having chronic pancreatitis the serum concentration of the immunoglobulins (IgA, IgG, IgM), the IgG- and IgA-type non-organ-specific autoantibodies against nuclear material (ANA), smooth and striated muscle, mitochondria, basal membrane, and reti......In 60 consecutive patients clinically suspected of having chronic pancreatitis the serum concentration of the immunoglobulins (IgA, IgG, IgM), the IgG- and IgA-type non-organ-specific autoantibodies against nuclear material (ANA), smooth and striated muscle, mitochondria, basal membrane......, and reticulin, and the IgG- and IgA-type pancreas-specific antibodies against islet cells, acinus cells, and ductal cells (DA) were estimated blindly. In 23 of the patients chronic pancreatitis was verified, whereas chronic pancreatitis was rejected in 37 patients (control group). IgG and IgA were found...... in significantly higher concentrations in the patients with chronic pancreatitis than in the control group but within the normal range. ANA and DA occurred very frequently in both groups but with no statistical difference. Other autoantibodies only occurred sporadically. The findings of this study do not support...

GPCR-autoantibodies in chronic heart failure.

Science.gov (United States)

Boivin-Jahns, Valerie; Jahns, Roland

2018-06-01

Chronic heart failure (CHF) is a syndrome characterized by shortness of breath, fluid retention, and a progressive reduction in cardiac function. More than 60% of the cases are ischemic in origin (i.e., due to myo-cardial infarction) and about 30% are caused by non-ischemic myocardial damage (i.e., due to genetic or non-genetic causes like myocardial inflammation). Because of alterations in both cellular and humoral immunity patients with non-ischemic CHF often develop abnormal or misled immune responses, including cross-reacting antibodies and/or autoantibodies to various cardiac anti-gens. Non-ischemic myo-cardial damage was found to progress to CHF particularly, when associated (a) with the generation of autoantibodies directed against distinct myocyte membrane proteins critically involved in cardiac function - like G-protein coup-led membrane receptors (GPCRs), or (b) with virus persistence in the myocardium. This article will review current knowledge on the pathophysiological relevance of GPCR-autoreactivity in CHF by giving an overview on the so far available evidence from pre-clinical, clinical and epidemiological studies on the CHF-inducing potential of GPCR-autoantibodies and thereon based novel therapeutic approaches in GPCR autoantibody-associated CHF.

Insulin-like growth factor I and II in 14 animal species and man as determined by three radioligand assays and two bioassays

Energy Technology Data Exchange (ETDEWEB)

Zangger, I.; Zapf, J.; Froesch, E.R.

1987-01-01

Insulin-like growth factor I and II (IGF I and II) were determined by five different assays in human serum, in the sera of ten mammalian species and in chicken, turtle, and frog serum. Sera of all tested mammals contain two different IGFs corresponding to human immunoreactive IGF I and receptor reactive IGF II. Receptor reactive IGF II of most animal species does not show significant cross-reactivity in the RIA for human IGF II. IGF activity was also detected in sera of non-mammals, such as chicken and turtles, but not in frog serum. The IGF values obtained with the different assay system corresponded rather well: there is a good correlation between the values obtained in the protein binding and the fat cell assay, and between the results of the latter assays and the sum of immunoreactive IGF I and receptor reative IGF II. The results suggest that those regions in the IGF I and II molecules which are responsible for reactivity with the type I IGF and the insulin receptor have not essentially changed during evolution. Similarly, the C-region, which mainly determines the immunological properties of IGFs, appears to have remained relatively constant in the IGF I, but not in the IGF II molecule.

The prediction of type 1 diabetes by multiple autoantibody levels and their incorporation into an autoantibody risk score in relatives of type 1 diabetic patients.

Science.gov (United States)

Sosenko, Jay M; Skyler, Jay S; Palmer, Jerry P; Krischer, Jeffrey P; Yu, Liping; Mahon, Jeffrey; Beam, Craig A; Boulware, David C; Rafkin, Lisa; Schatz, Desmond; Eisenbarth, George

2013-09-01

We assessed whether a risk score that incorporates levels of multiple islet autoantibodies could enhance the prediction of type 1 diabetes (T1D). TrialNet Natural History Study participants (n = 784) were tested for three autoantibodies (GADA, IA-2A, and mIAA) at their initial screening. Samples from those positive for at least one autoantibody were subsequently tested for ICA and ZnT8A. An autoantibody risk score (ABRS) was developed from a proportional hazards model that combined autoantibody levels from each autoantibody along with their designations of positivity and negativity. The ABRS was strongly predictive of T1D (hazard ratio [with 95% CI] 2.72 [2.23-3.31], P < 0.001). Receiver operating characteristic curve areas (with 95% CI) for the ABRS revealed good predictability (0.84 [0.78-0.90] at 2 years, 0.81 [0.74-0.89] at 3 years, P < 0.001 for both). The composite of levels from the five autoantibodies was predictive of T1D before and after an adjustment for the positivity or negativity of autoantibodies (P < 0.001). The findings were almost identical when ICA was excluded from the risk score model. The combination of the ABRS and the previously validated Diabetes Prevention Trial-Type 1 Risk Score (DPTRS) predicted T1D more accurately (0.93 [0.88-0.98] at 2 years, 0.91 [0.83-0.99] at 3 years) than either the DPTRS or the ABRS alone (P ≤ 0.01 for all comparisons). These findings show the importance of considering autoantibody levels in assessing the risk of T1D. Moreover, levels of multiple autoantibodies can be incorporated into an ABRS that accurately predicts T1D.

Rapid induction of autoantibodies during ARDS and septic shock

Directory of Open Access Journals (Sweden)

Meduri G Umberto

2010-10-01

Full Text Available Abstract Background Little is known about the induction of humoral responses directed against human autoantigens during acute inflammation. We utilized a highly sensitive antibody profiling technology to study autoantibodies in patients with acute respiratory distress syndrome (ARDS and severe sepsis, conditions characterized by intensive immune activation leading to multiple organ dysfunction. Methods Using Luciferase Immunoprecipitation Systems (LIPS, a cohort of control, ARDS and sepsis patients were tested for antibodies to a panel of autoantigens. Autoantibody titers greater than the mean plus 3 SD of the 24 control samples were used to identify seropositive samples. Available longitudinal samples from different seropositive ARDS and sepsis patient samples, starting from within the first two days after admission to the intensive care, were then analyzed for changes in autoantibody over time. Results From screening patient plasma, 57% of ARDS and 46% of septic patients without ARDS demonstrated at least one statistically significant elevated autoantibody compared to the controls. Frequent high titer antibodies were detected against a spectrum of autoantigens including potassium channel regulator, gastric ATPase, glutamic decarboxylase-65 and several cytokines. Analysis of serial samples revealed that several seropositive patients had low autoantibodies at early time points that often rose precipitously and peaked between days 7-14. Further, the use of therapeutic doses of corticosteroids did not diminish the rise in autoantibody titers. In some cases, the patient autoantibody titers remained elevated through the last serum sample collected. Conclusion The rapid induction of autoantibodies in ARDS and severe sepsis suggests that ongoing systemic inflammation and associated tissue destruction mediate the break in tolerance against these self proteins.

Effects of insulin on perfused liver from streptozotocin-diabetic and untreated rats: 13C NMR assay of pyruvate kinase flux

International Nuclear Information System (INIS)

Cohen, S.M.

1987-01-01

The effects of insulin in vitro on perfused liver from streptozotocin-diabetic rats and their untreated littermates during gluconeogenesis from either [3- 13 C]alanine + ethanol or [2- 13 C]pyruvate + NH 4 Cl + ethanol were studied by 13 C NMR. A 13 C NMR determination of the rate of pyruvate kinase flux under steady-state conditions of active gluconeogenesis was developed; this assay includes a check on the reuse of recycled pyruvate. The preparations studied provided gradations of pyruvate kinase flux within the confines of the assay's requirement of active gluconeogenesis. By this determination, the rate of pyruvate kinase flux was 0.74 +/- 0.04 of the gluconeogenic rate in liver from 24-h-fasted controls; in liver from 12-h fasted controls, relative pyruvate kinase flux increased to 1.0 +/- 0.2. In diabetic liver, this flux was undetectable by the authors NMR method. Insulin's hepatic influence in vitro was greatest in the streptozotocin model of type 1 diabetes: upon treatment of diabetic liver with 7 nM insulin in vitro, a partial reversal of many of the differences noted between diabetic and control liver was demonstrated by 13 C NMR. A major effect of insulin in vitro upon diabetic liver was the induction of a large increase in the rate of pyruvate kinase flux, bringing relative and absolute fluxes up to the levels measured in 24-h-fasted controls. By way of comparison, the effects of ischemia on diabetic liver were studied by 13 C NMR to test whether changes in allosteric effectors under these conditions could also increase pyruvate kinase flux. A large increase in this activity was demonstrated in ischemic diabetic liver

The prevalence of autoantibody and its relationship with genotypes of hepatitis C virus in patients with chronic hepatitis C virus infection.

Science.gov (United States)

Kirdar, Sevİn; Sener, Asli Gamze; Cengİz, Merve; Aydin, Nerİman

2016-11-01

The prevalence of autoantibody in the patients with chronic hepatitis C infection, and the relationship between the autoantibodies and HCV genotypes were investigated in this study. One hundred and eight anti-HCV positive and 86 anti-HCV negative patients were included in the study. Anti-HCV were studied by enzyme immunassay (EIA). HCV RNA was determined by real time polymerase chain reaction (PCR) and HCV genotypes were determined by a reverse-line blot hybridization. Anti-nuclear antibodies (ANA), anti-smooth muscle antibodies (ASMA), Anti-mitochondrial antibodies (AMA), liver kidney microsomal antibodies (LKM) were detected by indirect immunofluorescence assay. Among patients, 13 (12.03%) of 108 were positive for at least one autoantibody. The positivity was not observed in control group. The most prevalent autoantibody in anti-HCV positive group was ANA. ANA was positive in six HCV patients with genotype 1. In HCV patients with genotype 1, the frequencies of ANA, ASMA, AMA and LKM1 were six, two, three and one, respectively. In HCV patients with genotype 2, ANA was positive one patient and ASMA, AMA and LKM1 were not detected in HCV patients with genotype 2. In conclusion, the autoantibodies in patients with chronic hepatitis C in the study were low as compared to those reported in previous studies. © 2016 APMIS. Published by John Wiley & Sons Ltd.

Autoantibody Profiling in Lupus Patients using Synthetic Nucleic Acids

DEFF Research Database (Denmark)

Klecka, Martin; Thybo, Christina; Macaubas, Claudia

2018-01-01

specificity and reproducibility. Applying the ELISA tests to serological studies of pediatric and adult SLE, we identified novel clinical correlations. We also observed preferential recognition of a specific synthetic antigen by antibodies in SLE sera. We determined the probable basis for this finding using...... computational analyses, providing valuable structural information for future development of DNA antigens. Synthetic nucleic acid molecules offer the opportunity to standardize assays and to dissect antibody-antigen interactions.......Autoantibodies to nuclear components of cells (antinuclear antibodies, ANA), including DNA (a-DNA), are widely used in the diagnosis and subtyping of certain autoimmune diseases, including systemic lupus erythematosus (SLE). Despite clinical use over decades, precise, reproducible measurement of a...

Measurement of thyroid-stimulating autoantibodies using a radioreceptor-assay (TRAK-assay)

International Nuclear Information System (INIS)

Becker, W.; Reiners, C.; Boerner, W.

1983-01-01

Autoantibodes against TSH-receptors were determined with a new radioreceptorassay (TRAK-assay) in 37 patients with untreated toxic diffus goitre and in 73 patients with non immunogenic thyroid diseases (41 healthy controls, respectively patients with euthyroid diffus or nodular goitres as well as 32 patients with toxic nodular goitre). The upper limit of normal is a TRAK-Titer of 20% without considerable fluctuations during titers in follow-up. According to this preliminary results it seems to be recommendable to treat patients with TRAK-titer F 20% (expected risk of relapse) primarily by operation or radioiodine. (orig.) [de

Extrahepatic Manifestations and Autoantibodies in Patients with Hepatitis C Virus Infection

Directory of Open Access Journals (Sweden)

Takashi Himoto

2012-01-01

Full Text Available Patients with chronic hepatitis C virus (HCV infection frequently have many extrahepatic manifestations, as persistent HCV infection often triggers lymphoproliferative disorders and metabolic abnormalities. These manifestations primarily include autoimmune disorders such as cryoglobulinemia, Sjögren’s syndrome, and autoimmune thyroid disorders. It has been well established that chronic HCV infection plays important roles in the production of non-organ-specific autoantibodies, including antinuclear antibodies and smooth muscle antibodies, and organ-specific autoantibodies such as thyroid autoantibodies. However, the clinical significance of autoantibodies associated with the extrahepatic manifestations caused by HCV infection has not been fully recognized. In this paper, we mainly focus on the relationship between extrahepatic manifestations and the emergence of autoantibodies in patients with HCV infection and discuss the clinical relevance of the autoantibodies in the extrahepatic disorders.

Comparison and validation of ELISA assays for plasma insulin-like growth factor-1 in the horse

Directory of Open Access Journals (Sweden)

Courtnay L. Baskerville

2017-03-01

Full Text Available Insulin-like growth factor-1 (IGF-1 plays several important physiological roles, and IGF-related pathways have been implicated in developmental osteochondral disease and endocrinopathic laminitis. This factor is also a downstream marker of growth hormone activity and its peptide mimetics. Unfortunately, previously used assays for measuring equine IGF-1 (radioimmunoassays and ELISAs are no longer commercially available, and many of the kits on the market give poor results when used on horse samples. The aim of the present study was to compare three different ELISA assays (two human and one horse-specific. Plasma samples from six Standardbreds, six ponies and six Andalusians were used. The human IGF-1 ELISA kit from Immunodiagnostic Systems (IDS proved to be the most accurate and precise of the three kits; the other two assays gave apparently much lower concentrations, with poor recovery of spiked recombinant human IGF-1 and unacceptably poor intra-assay coefficients of variation (CV. The IDS assay gave an intra-assay CV of 3.59 % and inter-assay CV of 7.31%. Mean percentage recovery of spiked IGF-1 was 88.82%, and linearity and dilutional parallelism were satisfied. The IGF-1 plasma concentrations were 123.21 ±8.24 ng/mL for Standardbreds, 124.95 ±3.69 ng/mL for Andalusians and 174.26 ±1.94 ng/mL for ponies. Therefore of the three assays assessed, the IGF-1 ELISA manufactured by IDS was the most suitable for use with equine plasma samples and may have many useful applications in several different research areas. However, caution should be used when comparing equine studies where different analytical techniques and assays may have been used to measure this growth factor.

Immunospecific red cell binding of iodine 125-labeled immunoglobulin G erythrocyte autoantibodies

International Nuclear Information System (INIS)

Masouredis, S.P.; Branks, M.J.; Garratty, G.; Victoria, E.J.

1987-01-01

The primary interaction of autoantibodies with red cells has been studied by using labeled autoantibodies. Immunoglobulin G red cell autoantibodies obtained from IgG antiglobulin-positive normal blood donors were labeled with radioactive iodine and compared with alloanti-D with respect to their properties and binding behavior. Iodine 125 -labeled IgG autoantibody migrated as a single homogeneous peak with the same relative mobility as human IgG on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The isoelectric focusing pattern of labeled autoantibodies varied from donor to donor but was similar to that of alloanti-D, consisting of multiple IgG populations with isoelectric points in the neutral to alkaline range. 125 I-autoantibody bound to all human red cells of common Rh phenotypes. Evidence for immunospecific antibody binding of the labeled autoantibody was based on variation in equilibrium binding to nonhuman and human red cells of common and rare phenotypes, enhanced binding after red cell protease modification, antiglobulin reactivity of cell-bound IgG comparable to that of cell-bound anti-D, and saturation binding in autoantibody excess. Scatchard analysis of two 125 I-autoantibody preparations yielded site numbers of 41,500 and 53,300 with equilibrium constants of 3.7 and 2.1 X 10(8) L X mol-1. Dog, rabbit, rhesus monkey, and baboon red cells were antigen(s) negative by quantitative adsorption studies adsorbing less than 3% of the labeled autoantibody. Reduced ability of rare human D--red blood cells to adsorb the autoantibody and identification of donor autoantibodies that bind to Rh null red blood cells indicated that eluates contained multiple antibody populations of complex specificities in contrast to anti-D, which consists of a monospecific antibody population. Another difference is that less than 70% of the autoantibody IgG was adsorbed by maximum binding red blood cells as compared with greater than 85% for alloanti-D

Combining EL4-B5-based B-cell stimulation and phage display technology for the successful isolation of human anti-Scl-70 autoantibody fragments.

Science.gov (United States)

Weber, Malte; Weiss, Etienne; Engel, Alfred M

2003-07-01

Scl-70 is the major antigen recognised by autoantibodies in the sera of patients with systemic sclerosis (SSc). The autoantibodies that specifically react with Scl-70 are highly characteristic of the disease and represent valuable markers for the diagnosis of SSc. We describe a novel strategy for cloning autoantibody fragments starting with a small blood sample from an SSc patient. B cells isolated from the collected peripheral blood mononuclear cells (PBMCs) were cultured in vitro using the EL4-B5 system. Anti-Scl-70 IgG-producing cells were pooled for RNA preparation followed by the generation of phagemid libraries of approximately 10(7) independent single-chain Fvs (scFvs). The screening of these libraries by phage display allowed us to isolate four anti-Scl-70 scFvs following three rounds of biopanning. About 10 times more starting blood material was needed to generate scFv libraries of similar size from PBMCs of an SSc patient and only two anti-Scl-70 scFvs were isolated after three rounds of phage selection. Together, this work shows that functional autoantibody fragments can be advantageously cloned after in vitro expansion of B cells. The isolated anti-Scl-70 autoantibody fragments represent useful tools for calibrating SSc diagnostic assays.

The determination of thyroid hormone autoantibodies and its clinical significance

International Nuclear Information System (INIS)

Zhu Li; Zhao Zhiying; Wang Zhenghua Lian Xiaolan; Guo Zhisheng; Bai Yao; Su Wei

2003-01-01

To study the reasons of falsely high concentrations of serum thyroid hormone and the way of determination of thyroid hormone autoantibodies, the experiments of thyroid hormone autoantibodies binding reaction, dilution testing, calibration curves and their check analysis were performed. Results showed that the combination of the autoantibodies with 125 I-T 3 or 125 I-T 4 was specific, the binding rates were 58.77% and 49.05% respectively and 7-12 times higher than control groups. The radioactive peaks of the autoantibodies and rabbit anti-T 3 or T 4 antibody appeared on the same position in radio electrophoretogram analysis and these antibodies were considered as IgG. The important reasons of falsely high concentrations of serum thyroid hormone are the presence of anti-thyroid hormone antibodies. Determination of thyroid hormone autoantibodies significantly benefits diagnosis and treatment of thyroid disease

Evaluation of classical and novel autoantibodies for the diagnosis of Primary Biliary Cholangitis-Autoimmune Hepatitis Overlap Syndrome (PBC-AIH OS).

Science.gov (United States)

Nguyen, Henry H; Shaheen, Abdel Aziz; Baeza, Natalia; Lytvyak, Ellina; Urbanski, Stefan J; Mason, Andrew L; Norman, Gary L; Fritzler, Marvin J; Swain, Mark G

2018-01-01

Up to 20% of Primary Biliary Cholangitis (PBC) patients are estimated to have features that overlap with Autoimmune Hepatitis (AIH). Patients with PBC-AIH overlap syndrome (PBC-AIH OS) have been reported to exhibit suboptimal responses to ursodeoxycholic acid therapy, and are more likely to progress to cirrhosis. Anti-double stranded DNA (anti-dsDNA) and anti-p53 have been previously suggested to be potential autoantibodies for identifying patients with PBC-AIH OS. In our well defined PBC patient cohorts, a comprehensive assessment of various classical and novel autoantibodies was evaluated for their utility in identifying PBC-AIH OS patients. PBC-AIH OS was classified according to the Paris criteria and PBC as per the European Association for the Study of the Liver guidelines. Biobanked serum samples from 197 patients at the University of Calgary Liver Unit and the University of Alberta were analyzed for classical and novel autoantibodies. Anti-dsDNA was measured by the Crithidia luciliae immunofluorescence (CLIFT) assay (1:20 dilution) and chemiluminescence (CIA: QUANTA Flash®, Inova Diagnostics, San Diego). Anti-p53, anti-Ro52/TRIM21, anti-YB 1, anti-GW182, anti-Ge-1, and anti-Ago 2 were measured by either an addressable laser bead immunoassay (ALBIA) or line immunoassay (LIA). Autoantibodies against MIT3, gp210, sp100, LKM1, SLA, and the novel autoantibodies Hexokinase-1 (HK-1), and Kelch like protein 12 (KLHL-12) were measured using QUANTA Lite® ELISA assays. We applied non-parametric methods to compare the biomarkers frequencies between study groups. We used multivariate adjusted models and AUROC to compare the diagnostic accuracy of the different autoantibodies alone or in combination with serum biochemistry. 16 out of 197 PBC patients (8.1%) were classified as PBC-AIH OS. Compared to PBC patients, PBC-AIH OS patients were similar in age (median: 59 vs. 63, P = 0.21) and female predominance (94% vs. 89%, P = 1.00). Anti-dsDNA-by CLIFT (37.5% in PBC-AIH OS

Myositis-specific autoantibodies: an important tool to support diagnosis of myositis.

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Betteridge, Z; McHugh, N

2016-07-01

The idiopathic inflammatory myopathies are characterized by muscle weakness, skin disease and internal organ involvement. Autoimmunity is known to have a role in myositis pathogenesis, and myositis-specific autoantibodies, targeting important intracellular proteins, are regarded as key biomarkers aiding in the diagnosis of patients. In recent years, a number of novel myositis autoantibodies including anti-TIF1, anti-NXP2, anti-MDA5, anti-SAE, anti-HMGCR and anti-cN1A have been identified in both adult and juvenile patients. These autoantibodies correlate with distinct clinical manifestations and importantly are found in inclusion body, statin-induced, clinically amyopathic and juvenile groups of myositis patients, previously believed to be mainly autoantibody negative. In this review, we will describe the main myositis-specific and myositis-associated autoantibodies and their frequencies and clinical associations across different ages and ethnic groups. We will also discuss preliminary studies investigating correlations between specific myositis autoantibody titres and clinical markers of disease course, collectively demonstrating the utility of myositis autoantibodies as both diagnostic and prognostic markers of disease. © 2015 The Association for the Publication of the Journal of Internal Medicine.

Autoantibodies in SLE: Specificities, Isotypes and Receptors

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Barbara Dema

2016-01-01

Full Text Available Systemic Lupus Erythematosus (SLE is characterized by a wide spectrum of auto-antibodies which recognize several cellular components. The production of these self-reactive antibodies fluctuates during the course of the disease and the involvement of different antibody-secreting cell populations are considered highly relevant for the disease pathogenesis. These cells are developed and stimulated through different ways leading to the secretion of a variety of isotypes, affinities and idiotypes. Each of them has a particular mechanism of action binding to a specific antigen and recognized by distinct receptors. The effector responses triggered lead to a chronic tissue inflammation. DsDNA autoantibodies are the most studied as well as the first in being characterized for its pathogenic role in Lupus nephritis. However, others are of growing interest since they have been associated with other organ-specific damage, such as anti-NMDAR antibodies in neuropsychiatric clinical manifestations or anti-β2GP1 antibodies in vascular symptomatology. In this review, we describe the different auto-antibodies reported to be involved in SLE. How autoantibody isotypes and affinity-binding to their antigen might result in different pathogenic responses is also discussed.

Clinical and Pathological Roles of Ro/SSA Autoantibody System

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Ryusuke Yoshimi

2012-01-01

Full Text Available Anti-Ro/SSA antibodies are among the most frequently detected autoantibodies against extractable nuclear antigens and have been associated with systemic lupus erythematosus (SLE and Sjögren's syndrome (SS. Although the presence of these autoantibodies is one of the criteria for the diagnosis and classification of SS, they are also sometimes seen in other systemic autoimmune diseases. In the last few decades, the knowledge of the prevalence of anti-Ro/SSA antibodies in various autoimmune diseases and symptoms has been expanded, and the clinical importance of these antibodies is increasing. Nonetheless, the pathological role of the antibodies is still poorly understood. In this paper, we summarize the milestones of the anti-Ro/SSA autoantibody system and provide new insights into the association between the autoantibodies and the pathogenesis of autoimmune diseases.

21 CFR 866.5870 - Thyroid autoantibody immunological test system.

Science.gov (United States)

2010-04-01

... the thyroid autoantibodies (antibodies produced against the body's own tissues). Measurement of thyroid autoantibodies may aid in the diagnosis of certain thyroid disorders, such as Hashimoto's disease (chronic lymphocytic thyroiditis), nontoxic goiter (enlargement of thyroid gland), Grave's disease...

Measurement of anti- acetylcholine receptor auto-antibodies in ...

African Journals Online (AJOL)

auto-antibodies in myasthenia gravis. K. J. Steenkamp, W. Duim, M. s. Myer,. S. C. K. Malfeld, R. Anderson. Two different acetylcholine receptor (AChR) preparations derived from ... the detection of AChR auto-antibodies in serum specimens from 20 ... 4°C. Thereafter, 1 ml of washing solution (phosphate- buffered saline ...

Development of a standardized ELISA for the determination of autoantibodies against human M-type phospholipase A2 receptor in primary membranous nephropathy

NARCIS (Netherlands)

Dahnrich, C.; Komorowski, L.; Probst, C.; Seitz-Polski, B.; Esnault, V.; Wetzels, J.F.M.; Hofstra, J.M.; Hoxha, E.; Stahl, R.A.K.; Lambeau, G.; Stocker, W.; Schlumberger, W.

2013-01-01

BACKGROUND: Autoantibodies against the M-type phospholipase A2 receptor (PLA2R1) are specific markers for primary membranous nephropathy (pMN) and anti-PLA2R1 serum levels may be useful to monitor disease activity. So far, a recombinant cell-based indirect immunofluorescence assay (RC-IFA) using

Significance of myositis autoantibody in patients with idiopathic interstitial lung disease.

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Song, Ju Sun; Hwang, Jiwon; Cha, Hoon-Suk; Jeong, Byeong-Ho; Suh, Gee Young; Chung, Man Pyo; Kang, Eun-Suk

2015-05-01

Some patients with interstitial lung disease (ILD) related to connective tissue disease (CTD) have a delayed diagnosis of the underlying CTD when the ILD is categorized as idiopathic. In this study, we evaluated the frequency of myositis autoantibodies in patients diagnosed with idiopathic ILD and investigated the clinical significance stemming from the presence of the antibodies. A total 32 patients diagnosed with idiopathic ILD were enrolled in this study. We analyzed a panel of 11 myositis autoantibody specificities in the patients using a line blot immunoassay. Then, we divided them into myositis autoantibody-positive and -negative groups and compared the clinical features and laboratory data between the two groups. Of the 32 idiopathic ILD patients, 12 patients had myositis autoantibodies encompassing 9 specificities, except for anti-Mi-2 and anti-PM-Scl 100 (12/32, 38%). Anti-synthetase autoantibodies including Jo-1, EJ, OJ, PL-7, and PL-12 were present in 7 patients (7/32, 22%). The group with myositis autoantibodies presented more frequently with the symptom of mechanic's hand and showed abnormal pulmonary function test results with low forced vital capacity, diffusing capacity for carbon monoxide, total lung capacity, and high lactate dehydrogenase values in blood when compared with the group without myositis antibodies. We strongly suggest that patients undergo an evaluation of myositis autoantibodies, if they are diagnosed with idiopathic ILD in the presence of clinical characteristics including mechanic's hand, arthralgia, and autoantibodies which are insufficient to make a diagnosis of a specific CTD category.

Latent autoimmune diabetes of adults: From oral hypoglycemic agents to early insulin

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Resham R Poudel

2012-01-01

Full Text Available Approximately 10% of phenotypic type 2 diabetics have islet autoantibodies and are referred to as having latent autoimmune diabetes of adults (LADA, and they land on early sulfonylurea failure and require insulin. Diagnosing LADA has treatment implications because of high risk of progression to insulin dependency. But often there is delay in insulin therapy, as there are no recommendations for islet antibody testing in adult-onset diabetes currently. LADA clinical risk score can identify adults at high risk who may benefit from antibody testing. The optimal treatment of LADA is not established. Early insulin therapy helps to achieve good metabolic control and better long-term outcomes by preserving b-cells and endogenous C-peptide secretion. Sulfonylureas are better avoided as they exhaust b-cells; glitazones and exenatide have favorable outcomes, whereas metformin needs to be used with caution. Understanding LADA will also bring new windows in managing type 1 diabetes. Information acquisition was done by reviewing the medical literature published since 1987, with particular attention to the natural history, genetic factors, and treatment of LADA.

Positive autoantibodies to ZnT8 indicate elevated risk for additional autoimmune conditions in patients with Addison's disease.

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Fichna, Marta; Rogowicz-Frontczak, Anita; Żurawek, Magdalena; Fichna, Piotr; Gryczyńska, Maria; Zozulińska-Ziółkiewicz, Dorota; Ruchała, Marek

2016-07-01

Autoimmune Addison's disease (AAD) associates with exceptional susceptibility to develop other autoimmune conditions, including type 1 diabetes (T1D), marked by positive serum autoantibodies to insulin (IAA), glutamic acid decarboxylase (GADA) and insulinoma-associated protein 2 (IA-2A). Zinc transporter 8 (ZnT8) is a new T1D autoantigen, encoded by the SLC30A8 gene. Its polymorphic variant rs13266634C/T seems associated with the occurrence of serum ZnT8 antibodies (ZnT8A). This study was designed to determine the prevalence of serum ZnT8A and their clinical implication in 140 AAD patients. Other beta cell and thyroid-specific autoantibodies were also investigated, and ZnT8A results were confronted with the rs13266634 genotype. ZnT8A were detectable in 8.5 %, GADA in 20.7 %, IA-2A in 5.7 %, IAA in 1.6 % and various anti-thyroid antibodies in 7.1-67.8 % individuals. Type 1 diabetes was found in 10 % AAD patients. ZnT8A were positive in 57.1 % of T1D patients and 3.4 % non-diabetic AAD. Analysis of ZnT8A enabled to identify autoimmunity in two (14.3 %) T1D individuals previously classified as autoantibody-negative. ZnT8A-positive patients revealed significantly higher number of autoimmune conditions (p < 0.001), increased prevalence of T1D (p < 0.001) and other beta cell-specific autoantibodies. Carriers of the rs13266634 T-allele displayed increased frequency (p = 0.006) and higher titres of ZnT8A (p = 0.002). Our study demonstrates high incidence of ZnT8A in AAD patients. ZnT8A are associated with coexisting T1D and predictive of T1D in non-diabetic subjects. Moreover, positive ZnT8A in AAD indicate elevated risk for additional autoimmune conditions. Autoantibodies to beta cell antigens, comprising ZnT8, could be included in routine screening panels in AAD.

Anti-glomerular basement membrane autoantibodies in the Brown Norway rat: detection by a solid-phase radioimmunoassay

International Nuclear Information System (INIS)

Bowman, C.; Peters, D.K.; Lockwood, C.M.

1983-01-01

A solid-phase radioimmunoassay (RIA) is described for the detection of IgG autoantibodies to glomerular basement membrane (GBM) induced in the Brown Norway rat by mercuric chloride. The assay involves the adsorption of a collagenase digest of GBM to plastic microtitre plates and detection of bound antibody with affinity purified radiolabelled rabbit anti-rat IgG. Comparison with existing immunofluorescence methods for detection of anti-GBM antibody showed that the solid-phase RIA is highly sensitive, allowing detection of antibody in solutions with as low as 0.5 ng protein/ml. The assay is suitable for detection of anti-GBM antibody both in serum and in eluates from nephritic kidneys. The assay proved to be specific in competitive studies of inhibition brought about by GBM, keyhole limpet antigen and ovalbumin. This solid-phase RIA is reproducible, robust and easy to perform. (Auth.)

Anti-IL-1alpha autoantibodies in early rheumatoid arthritis

DEFF Research Database (Denmark)

Forslind, K; Svensson, Birte; Svenson, M

2001-01-01

To investigate the potential predictive value of autoantibodies against IL1-alpha (anti-IL-1alpha) in patients with early rheumatoid arthritis (RA).......To investigate the potential predictive value of autoantibodies against IL1-alpha (anti-IL-1alpha) in patients with early rheumatoid arthritis (RA)....

Autoantibody-Targeted Treatments for Acute Exacerbations of Idiopathic Pulmonary Fibrosis.

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Michael Donahoe

Full Text Available Severe acute exacerbations (AE of idiopathic pulmonary fibrosis (IPF are medically untreatable and often fatal within days. Recent evidence suggests autoantibodies may be involved in IPF progression. Autoantibody-mediated lung diseases are typically refractory to glucocorticoids and nonspecific medications, but frequently respond to focused autoantibody reduction treatments. We conducted a pilot trial to test the hypothesis that autoantibody-targeted therapies may also benefit AE-IPF patients.Eleven (11 critically-ill AE-IPF patients with no evidence of conventional autoimmune diseases were treated with therapeutic plasma exchanges (TPE and rituximab, supplemented in later cases with intravenous immunoglobulin (IVIG. Plasma anti-epithelial (HEp-2 autoantibodies and matrix metalloproteinase-7 (MMP7 were evaluated by indirect immunofluorescence and ELISA, respectively. Outcomes among the trial subjects were compared to those of 20 historical control AE-IPF patients treated with conventional glucocorticoid therapy prior to this experimental trial.Nine (9 trial subjects (82% had improvements of pulmonary gas exchange after treatment, compared to one (5% historical control. Two of the three trial subjects who relapsed after only five TPE responded again with additional TPE. The three latest subjects who responded to an augmented regimen of nine TPE plus rituximab plus IVIG have had sustained responses without relapses after 96-to-237 days. Anti-HEp-2 autoantibodies were present in trial subjects prior to therapy, and were reduced by TPE among those who responded to treatment. Conversely, plasma MMP7 levels were not systematically affected by therapy nor correlated with clinical responses. One-year survival of trial subjects was 46+15% vs. 0% among historical controls. No serious adverse events were attributable to the experimental medications.This pilot trial indicates specific treatments that reduce autoantibodies might benefit some severely-ill AE

Selection of well labelled insulin fractions for radioimmunoassay use

Energy Technology Data Exchange (ETDEWEB)

Awh, O D; Kim, J R [Korea Atomic Energy Research Inst., Seoul (Republic of Korea)

1980-06-01

Selection methods of well labelled insulin fractions based on two different criteria were compared to establish an efficient low level RIA of insulin and to elucidate the correlation between the immunoreactivity and the charcoal-adsorptivity of the radioiodine labelled insulin. The result indicated that the selection of well labelled insulin fractions by means of a charcoal-adsorption test is inappropriate. Generally, the distribution of radioactivity, antibody-bindability, and charcoal-adsorptivity of the labelled insulin was not consistent with each other. Thus, the selection should be carried out for every labelling batch to get the utmost assay reliability by antibody-bindability but not by charcoal-adsorptivity. By using the well selected labelled insulin fractions based on antibody-binding, a correct assay for a reference serum was possible, and by extending the incubation time up to 96 hrs, a sharp dose response curve could be obtained even in the range of below 5 ..mu..U/ml standard insulin doses.

Autoantibodies against Cytochrome P450 Side-Chain Cleavage Enzyme in Dogs (Canis lupus familiaris) Affected with Hypoadrenocorticism (Addison's Disease).

Science.gov (United States)

Boag, Alisdair M; Christie, Michael R; McLaughlin, Kerry A; Syme, Harriet M; Graham, Peter; Catchpole, Brian

2015-01-01

Canine hypoadrenocorticism likely arises from immune-mediated destruction of adrenocortical tissue, leading to glucocorticoid and mineralocorticoid deficiency. In humans with autoimmune Addison's disease (AAD) or autoimmune polyendocrine syndrome (APS), circulating autoantibodies have been demonstrated against enzymes associated with adrenal steroid synthesis. The current study investigates autoantibodies against steroid synthesis enzymes in dogs with spontaneous hypoadrenocorticism. Coding regions of canine CYP21A2 (21-hydroxylase; 21-OH), CYP17A1 (17-hydroxylase; 17-OH), CYP11A1 (P450 side-chain cleavage enzyme; P450scc) and HSD3B2 (3β hydroxysteroid dehydrogenase; 3βHSD) were amplified, cloned and expressed as 35S-methionine radiolabelled recombinant protein. In a pilot study, serum samples from 20 dogs with hypoadrenocorticism and four unaffected control dogs were screened by radio-immunoprecipitation assay. There was no evidence of reactivity against 21-OH, 17-OH or 3βHSD, but five dogs with hypoadrenocorticism showed immunoreactivity to P450scc compared with controls. Serum samples were subsequently obtained from 213 dogs diagnosed with hypoadrenocorticism and 110 dogs from a hospital control population. Thirty control dogs were randomly selected to establish a threshold for antibody positivity (mean + 3 × standard deviation). Dogs with hypoadrenocorticism were more likely to be P450scc autoantibody positive than hospital controls (24% vs. 1.2%, respectively; p = 0.0016). Sex was significantly associated with the presence of P450scc autoantibodies in the case population, with 30% of females testing positive compared with 17% of males (p = 0.037). Significant associations with breed (p = 0.015) and DLA-type (DQA1*006:01 allele; p = 0.017) were also found. This cross-sectional study indicates that P450scc autoantibodies are present in a proportion of dogs affected with hypoadrenocorticism.

Autoantibodies against Cytochrome P450 Side-Chain Cleavage Enzyme in Dogs (Canis lupus familiaris Affected with Hypoadrenocorticism (Addison's Disease.

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Alisdair M Boag

Full Text Available Canine hypoadrenocorticism likely arises from immune-mediated destruction of adrenocortical tissue, leading to glucocorticoid and mineralocorticoid deficiency. In humans with autoimmune Addison's disease (AAD or autoimmune polyendocrine syndrome (APS, circulating autoantibodies have been demonstrated against enzymes associated with adrenal steroid synthesis. The current study investigates autoantibodies against steroid synthesis enzymes in dogs with spontaneous hypoadrenocorticism. Coding regions of canine CYP21A2 (21-hydroxylase; 21-OH, CYP17A1 (17-hydroxylase; 17-OH, CYP11A1 (P450 side-chain cleavage enzyme; P450scc and HSD3B2 (3β hydroxysteroid dehydrogenase; 3βHSD were amplified, cloned and expressed as 35S-methionine radiolabelled recombinant protein. In a pilot study, serum samples from 20 dogs with hypoadrenocorticism and four unaffected control dogs were screened by radio-immunoprecipitation assay. There was no evidence of reactivity against 21-OH, 17-OH or 3βHSD, but five dogs with hypoadrenocorticism showed immunoreactivity to P450scc compared with controls. Serum samples were subsequently obtained from 213 dogs diagnosed with hypoadrenocorticism and 110 dogs from a hospital control population. Thirty control dogs were randomly selected to establish a threshold for antibody positivity (mean + 3 × standard deviation. Dogs with hypoadrenocorticism were more likely to be P450scc autoantibody positive than hospital controls (24% vs. 1.2%, respectively; p = 0.0016. Sex was significantly associated with the presence of P450scc autoantibodies in the case population, with 30% of females testing positive compared with 17% of males (p = 0.037. Significant associations with breed (p = 0.015 and DLA-type (DQA1*006:01 allele; p = 0.017 were also found. This cross-sectional study indicates that P450scc autoantibodies are present in a proportion of dogs affected with hypoadrenocorticism.

Autoantibody profile in individuals with chronic hepatitis C.

Science.gov (United States)

Marconcini, Maíra Luciana; Fayad, Leonardo; Shiozawa, Maria Beatriz Cacese; Dantas-Correa, Esther Buzaglo; Lucca Schiavon, Leonardo de; Narciso-Schiavon, Janaína Luz

2013-01-01

Autoantibodies are often produced during infection with chronic hepatitis C virus (HCV), but it remains controversial whether they influence the biochemical profile and histological features of this disease. Therefore, this current study sought to describe these autoantibodies and evaluate their impact on the clinical and histological presentation of hepatitis C. This cross-sectional analytical study assessed patients with HCV (RNA+) from October 2011 to July 2012. This study included 66 patients, with a mean age of 53.2±10.5 years. Of these patients, 60.6% were male, and 54.3% presented with genotype 1. Non-organ-specific autoantibodies (NOSA) were detected in 24% of the patients; of these, 7.6% were anti-mitochondrial antibodies (AMA+), 26.7% were anti-smooth muscle antibodies (SMA+) and 6.8% were liver kidney microsomal type 1 antibodies (LKM1+). With respect to the thyroid autoantibodies, 7.4% were anti-peroxidase (ATPO+) antibodies, and none were anti-thyroglobulin (ATG+) antibodies. Regarding celiac disease autoantibodies, 5.8% were endomysial antibodies (EMA+), and no transglutaminase (TTG+) antibodies were detected. Cryoglobulins were found in 2.1% of patients. When NOSA+ individuals were compared to patients without the presence of NOSAs, they exhibited higher median alkaline phosphatase (0.7 vs. 0.6 xULN; p=0.041), lower median platelet counts (141,500.0 vs. 180,500.0/mm 3 ; p=0.036), lower mean prothrombin activity (72.6±11.5% vs. 82.2±16.0%; p=0.012) and an increased prevalence of significant fibrosis (E≥2) (45.5% vs. 18.2%; p=0.012). There was also a tendency for a greater proportion of NOSA+ cases to have marked periportal activity (APP≥3) (44.5% vs. 15.6%; p=0.087). In addition to the high prevalence of autoantibodies associated with HCV infection, it was observed that NOSA positivity was associated with a more severe histological and biochemical profile of hepatitis C infection.

Autoantibody profile in individuals with chronic hepatitis C

Directory of Open Access Journals (Sweden)

Maíra Luciana Marconcini

2013-04-01

Full Text Available Introduction Autoantibodies are often produced during infection with chronic hepatitis C virus (HCV, but it remains controversial whether they influence the biochemical profile and histological features of this disease. Therefore, this current study sought to describe these autoantibodies and evaluate their impact on the clinical and histological presentation of hepatitis C. Methods This cross-sectional analytical study assessed patients with HCV (RNA+ from October 2011 to July 2012. Results This study included 66 patients, with a mean age of 53.2±10.5 years. Of these patients, 60.6% were male, and 54.3% presented with genotype 1. Non-organ-specific autoantibodies (NOSA were detected in 24% of the patients; of these, 7.6% were anti-mitochondrial antibodies (AMA+, 26.7% were anti-smooth muscle antibodies (SMA+ and 6.8% were liver kidney microsomal type 1 antibodies (LKM1+. With respect to the thyroid autoantibodies, 7.4% were anti-peroxidase (ATPO+ antibodies, and none were anti-thyroglobulin (ATG+ antibodies. Regarding celiac disease autoantibodies, 5.8% were endomysial antibodies (EMA+, and no transglutaminase (TTG+ antibodies were detected. Cryoglobulins were found in 2.1% of patients. When NOSA+ individuals were compared to patients without the presence of NOSAs, they exhibited higher median alkaline phosphatase (0.7 vs. 0.6 xULN; p=0.041, lower median platelet counts (141,500.0 vs. 180,500.0/mm 3 ; p=0.036, lower mean prothrombin activity (72.6±11.5% vs. 82.2±16.0%; p=0.012 and an increased prevalence of significant fibrosis (E≥2 (45.5% vs. 18.2%; p=0.012. There was also a tendency for a greater proportion of NOSA+ cases to have marked periportal activity (APP≥3 (44.5% vs. 15.6%; p=0.087. Conclusions In addition to the high prevalence of autoantibodies associated with HCV infection, it was observed that NOSA positivity was associated with a more severe histological and biochemical profile of hepatitis C infection.

Biological variation of thyroid autoantibodies and thyroglobulin

DEFF Research Database (Denmark)

Jensen, Esther; Petersen, Per Hyltoft; Blaabjerg, Ole

2007-01-01

BACKGROUND: It has been shown that the level of serum thyroid antibodies affects serum thyrotropin (TSH) concentrations in men and women, and that these autoantibodies in combination with serum TSH are predictive of future thyroid disease. As the biological variation of these autoantibodies.......5-258 kIU/L), the CV biological was 11.3%, while the CV analytical was 10.6%. For TgAb (5.6 to 148 kIU/L) CV biological was 8.5% and CV analytical was 9.0%. The woman with TRAb had a CV biological of 4.8%, while the analytical variation in duplicates was 3.9% at a level of 2.8 IU/L. CONCLUSIONS......: It is possible to measure TPOAb and TgAb in all samples with the AutoDELFIA. There is no systematic variation in autoantibodies during the menstrual cycle. The biological coefficient of variation for TPOAb and TgAb was 11.3% and 8.5%, respectively...

Automatic computation of radioimmunoassay data. Insulin and C-peptide

Energy Technology Data Exchange (ETDEWEB)

Toyota, T; Kudo, M; Abe, K [Hirosaki Univ., Aomori (Japan). School of Medicine; Kawamata, F; Uehata, S

1975-09-01

Radioimmunoassay provided dose response curves which showed linearity by the use of logistic transformation (Rodbard). This transformation which was applicable to radioimmunoassay should be useful for the computer processing of insulin and C-peptide assay. In the present studies, standard curves were analysed by testing the fit of analytic functions to radioimmunoassay of insulin and C-peptides. A program for use in combination with the double antibody technique was made by Dr. Kawamata. This approach was evidenced to be useful in order to allow automatic computation of data derived from the double antibody assays of insulin and C-peptides. Automatic corrected calculations of radioimmunoassay data of insulin was found to be satisfactory.

Natural autoantibodies: from 'horror autotoxicus' to 'gnothi seauton'.

Science.gov (United States)

Avrameas, S

1991-05-01

The immune system of normal unimmunized animals is characterized by the presence of B cells synthesizing and secreting mainly polyreactive, but also monoreactive, IgM and IgG natural antibodies that can react with a variety of self constituents. These antibodies, like the autoantibodies appearing in several immunopathological states, use the same genetic elements as the antibodies directed against environmental antigens, and seem to be encoded by unmutated germ-line genes. Accumulating evidence indicates that these natural auto-antibodies exert various biological roles, both related and unrelated to the immune system. In this article, Stratis Avrameas proposes that natural auto-antibodies, by interacting with the large number of self constituents present in an organism, establish an extensive dynamic network that contributes to the general homeostasis of the organism.

Effects of turtle oil on insulin sensitivity and glucose metabolism in insulin resistant cell model

International Nuclear Information System (INIS)

Bai Jing; Tian Yaping; Guo Duo

2007-01-01

To evaluate the effects of turtle oil on insulin sensitivity and glucose metabolism in an insulin-resistant (IR) cell model which was established by the way of high concentration of insulin induction with HepG 2 cell in vitro culture. The IR cells were treated by turtle oil, the glucose consumption and 3 H-D-glucose incorporation rate in IR cells were detected by the way of glucose oxidase and 3 H-D-glucose incorporation assay respectively. The state of cell proliferation was tested by MTT method. The results showed that the incorporation rate of 3 H-D-glucose in IR cells was significantly lower than that in the control cells(P 3 H-D-glucose incorporation rate in either IR cells or control cells was increased with the increase of insulin concentration. Moreover, the 3 H-D-glucose incorporation rate of IR cells increased slower than that of control cells. The MTT assay showed that turtle oil can promote the proliferation of IR cell and control cell. The glucose uptake and glucose consumption in IR cell which treated with turtle oil was significantly increase than that in the control cells (P<0.05). Turtle oil can improve the insulin sensitivity and glucose metabolism in the IR cell model. (authors)

LKM3 autoantibodies in hepatitis C cirrhosis: a further phenomenon of the HCV-induced autoimmunity.

Science.gov (United States)

Csepregi, A; Nemesánszky, E; Luettig, B; Obermayer-Straub, P; Manns, M P

2001-03-01

Chronic hepatitis C is frequently associated with laboratory markers-including LKM1 autoantibodies--of autoimmunity. A 62-yr-old woman with hepatitis C cirrhosis presented autoantibodies against liver and kidney microsomal proteins. By further evaluation of autoantibodies using ELISA and immunoblotting LKM1 and LKM3 autoantibodies could be revealed. The target antigen of LKM3 autoantibodies proved to be UGT-1.1 isoenzyme. In the absence of chronic hepatitis D infection or autoimmune hepatitis type 2, this is the first case that reports the occurrence of LKM3 autoantibodies in HCV-induced chronic liver disease.

Capillary blood islet autoantibody screening for identifying pre-type 1 diabetes in the general population: design and initial results of the Fr1da study.

Science.gov (United States)

Raab, Jennifer; Haupt, Florian; Scholz, Marlon; Matzke, Claudia; Warncke, Katharina; Lange, Karin; Assfalg, Robin; Weininger, Katharina; Wittich, Susanne; Löbner, Stephanie; Beyerlein, Andreas; Nennstiel-Ratzel, Uta; Lang, Martin; Laub, Otto; Dunstheimer, Desiree; Bonifacio, Ezio; Achenbach, Peter; Winkler, Christiane; Ziegler, Anette-G

2016-05-18

Type 1 diabetes can be diagnosed at an early presymptomatic stage by the detection of islet autoantibodies. The Fr1da study aims to assess whether early staging of type 1 diabetes (1) is feasible at a population-based level, (2) prevents severe metabolic decompensation observed at the clinical manifestation of type 1 diabetes and (3) reduces psychological distress through preventive teaching and care. Children aged 2-5 years in Bavaria, Germany, will be tested for the presence of multiple islet autoantibodies. Between February 2015 and December 2016, 100 000 children will be screened by primary care paediatricians. Islet autoantibodies are measured in capillary blood samples using a multiplex three-screen ELISA. Samples with ELISA results >97.5th centile are retested using reference radiobinding assays. A venous blood sample is also obtained to confirm the autoantibody status of children with at least two autoantibodies. Children with confirmed multiple islet autoantibodies are diagnosed with pre-type 1 diabetes. These children and their parents are invited to participate in an education and counselling programme at a local diabetes centre. Depression and anxiety, and burden of early diagnosis are also assessed. Of the 1027 Bavarian paediatricians, 39.3% are participating in the study. Overall, 26 760 children have been screened between February 2015 and November 2015. Capillary blood collection was sufficient in volume for islet autoantibody detection in 99.46% of the children. The remaining 0.54% had insufficient blood volume collected. Of the 26 760 capillary samples tested, 0.39% were positive for at least two islet autoantibodies. Staging for early type 1 diabetes within a public health setting appears to be feasible. The study may set new standards for the early diagnosis of type 1 diabetes and education. The study was approved by the ethics committee of Technische Universität München (Nr. 70/14). Published by the BMJ Publishing Group Limited. For

Thyroid Autoantibodies and the Clinical Presentation of Moyamoya Disease: A Prospective Study.

Science.gov (United States)

Lanterna, Luigi A; Galliani, Silvia; Zangari, Rosalia; Conti, Luciano; Brembilla, Carlo; Gritti, Paolo; Colleoni, Maria Luisa; Bernucci, Claudio

2018-05-01

Moyamoya is a rare cerebrovascular disease characterized by the progressive occlusion of the intracranial carotid artery. Thyroid autoantibodies have been found to be associated with the disease, but their clinical significance has never been studied. The objective of this study was to investigate the relationship between thyroid autoantibodies and the clinical presentation of moyamoya. This is a prospective study including 37 patients with moyamoya disease (MMD) or unilateral moyamoya (uMM). Thyroid function and thyroid autoantibodies (e.g., antithyroperoxidase and antithyroglobulin) were investigated. We studied the effect of gender, age, type of moyamoya (uMM versus MMD), and thyroid autoantibodies on the clinical presentation, dichotomized into aggressive (hemorrhage, major stroke, or frequent transient ischemic attack [TIA]) and nonaggressive presentation (headache, rare TIAs, and incidental diagnosis) according to the criteria of the Research Committee on Spontaneous Occlusion of the Circle of Willis. Of the 37 patients included in the study, the autoantibodies were elevated in 9 (24.3%). An aggressive presentation occurred in 21 patients (hemorrhage in 11, major stroke in 9, frequent TIAs in 1). The autoantibodies were elevated in 8 of the 21 patients (38.09%) with an aggressive presentation and in 1 of those presenting with minor symptoms (6.2%). The presence of elevated autoantibodies was the only variable associated with an aggressive presentation in the multivariate logistic analysis (P = .048). When the serum concentration of the thyroid autoantibodies is increased, the patients have a higher risk of an aggressive presentation. Our results support the hypothesis that activation of immune-mediated processes affects the moyamoya physiopathology. Copyright © 2018 National Stroke Association. Published by Elsevier Inc. All rights reserved.

TSH-receptor-autoantibody-titers in untreated toxic diffuse goitres - an early indicator of relapse

International Nuclear Information System (INIS)

Becker, W.; Reiners, C.; Boerner, W.

1984-01-01

TSH-receptor-auto antibodies were determined in follow-up of 30 patients with relapse of toxic diffuse goitres, i.e. patients with Graves' disease and toxic disseminated autonomy, and in 13 patients with spontaneous remission after antithyroid drug therapy by use of a commercially available TSH-radioreceptorassay (TRAK-assay). All the patients with very high receptor-autoantibody-titers in untreated thyrotoxicosis (F > 20%) had one or more periods of hyperthyroidism or a very severe course of disease. None of these patients showed a spontaneous remission of disease. They all could be identified as Graves' patients. Patients with TRAK-titers 3% [de

Brief Communication: Maternal Plasma Autoantibodies Screening in Fetal Down Syndrome

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Karol Charkiewicz

2016-01-01

Full Text Available Imbalance in the metabolites levels which can potentially be related to certain fetal chromosomal abnormalities can stimulate mother’s immune response to produce autoantibodies directed against proteins. The aim of the study was to determine the concentration of 9000 autoantibodies in maternal plasma to detect fetal Down syndrome. Method. We performed 190 amniocenteses and found 10 patients with confirmed fetal Down syndrome (15th–18th weeks of gestation. For the purpose of our control we chose 11 women without confirmed chromosomal aberration. To assess the expression of autoantibodies in the blood plasma, we used a protein microarray, which allows for simultaneous determination of 9000 proteins per sample. Results. We revealed 213 statistically significant autoantibodies, whose expression decreased or increased in the study group with fetal Down syndrome. The second step was to create a classifier of Down syndrome pregnancy, which includes 14 antibodies. The predictive value of the classifier (specificity and sensitivity is 100%, classification errors, 0%, cross-validation errors, 0%. Conclusion. Our findings suggest that the autoantibodies may play a role in the pathophysiology of Down syndrome pregnancy. Defining their potential as biochemical markers of Down syndrome pregnancy requires further investigation on larger group of patients.

Hydrolyzed infant formula and early β-cell autoimmunity

DEFF Research Database (Denmark)

Knip, Mikael; Åkerblom, Hans K; Becker, Dorothy

2014-01-01

-associated autoantibodies out of 4 analyzed. Autoantibodies to insulin, glutamic acid decarboxylase, and the insulinoma-associated-2 (IA-2) molecule were analyzed using radiobinding assays and islet cell antibodies with immunofluorescence during a median observation period of 7.0 years (mean, 6.3 years). RESULTS......IMPORTANCE: The disease process leading to clinical type 1 diabetes often starts during the first years of life. Early exposure to complex dietary proteins may increase the risk of β-cell autoimmunity in children at genetic risk for type 1 diabetes. Extensively hydrolyzed formulas do not contain...... intact proteins. OBJECTIVE: To test the hypothesis that weaning to an extensively hydrolyzed formula decreases the cumulative incidence of diabetes-associated autoantibodies in young children. DESIGN, SETTING, AND PARTICIPANTS: A double-blind randomized clinical trial of 2159 infants with HLA...

Autoantibodies to a 140-kd protein in juvenile dermatomyositis are associated with calcinosis.

LENUS (Irish Health Repository)

Gunawardena, H

2009-06-01

OBJECTIVE: The identification of novel autoantibodies in juvenile dermatomyositis (DM) may have etiologic and clinical implications. The aim of this study was to describe autoantibodies to a 140-kd protein in children recruited to the Juvenile DM National Registry and Repository for UK and Ireland. METHODS: Clinical data and sera were collected from children with juvenile myositis. Sera that recognized a 140-kd protein by immunoprecipitation were identified. The identity of the p140 autoantigen was investigated by immunoprecipitation\\/immunodepletion, using commercial monoclonal antibodies to NXP-2, reference anti-p140, and anti-p155\\/140, the other autoantibody recently described in juvenile DM. DNA samples from 100 Caucasian children with myositis were genotyped for HLA class II haplotype associations and compared with those from 864 randomly selected UK Caucasian control subjects. RESULTS: Sera from 37 (23%) of 162 patients with juvenile myositis were positive for anti-p140 autoantibodies, which were detected exclusively in patients with juvenile DM and not in patients with juvenile DM-overlap syndrome or control subjects. No anti-p140 antibody-positive patients were positive for other recognized autoantibodies. Immunodepletion suggested that the identity of p140 was consistent with NXP-2 (the previously identified MJ autoantigen). In children with anti-p140 antibodies, the association with calcinosis was significant compared with the rest of the cohort (corrected P < 0.005, odds ratio 7.0, 95% confidence interval 3.0-16.1). The clinical features of patients with anti-p140 autoantibodies were different from those of children with anti-p155\\/140 autoantibodies. The presence of HLA-DRB1*08 was a possible risk factor for anti-p140 autoantibody positivity. CONCLUSION: This study has established that anti-p140 autoantibodies represent a major autoantibody subset in juvenile DM. This specificity may identify a further immunogenetic and clinical phenotype within the

Harmonization of Glutamic Acid Decarboxylase and Islet Antigen-2 Autoantibody Assays for National Institute of Diabetes and Digestive and Kidney Diseases Consortia

OpenAIRE

Bonifacio, Ezio; Yu, Liping; Williams, Alastair K.; Eisenbarth, George S.; Bingley, Polly J.; Marcovina, Santica M.; Adler, Kerstin; Ziegler, Anette G.; Mueller, Patricia W.; Schatz, Desmond A.; Krischer, Jeffrey P.; Steffes, Michael W.; Akolkar, Beena

2010-01-01

Background/Rationale: Autoantibodies to islet antigen-2 (IA-2A) and glutamic acid decarboxylase (GADA) are markers for diagnosis, screening, and measuring outcomes in National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) consortia studies. A harmonization program was established to increase comparability of results within and among these studies.

The myositis autoantibody phenotypes of the juvenile idiopathic inflammatory myopathies.

Science.gov (United States)

Rider, Lisa G; Shah, Mona; Mamyrova, Gulnara; Huber, Adam M; Rice, Madeline Murguia; Targoff, Ira N; Miller, Frederick W

2013-07-01

The juvenile idiopathic inflammatory myopathies (JIIM) are systemic autoimmune diseases characterized by skeletal muscle weakness, characteristic rashes, and other systemic features. In follow-up to our study defining the major clinical subgroup phenotypes of JIIM, we compared demographics, clinical features, laboratory measures, and outcomes among myositis-specific autoantibody (MSA) subgroups, as well as with published data on adult idiopathic inflammatory myopathy patients enrolled in a separate natural history study. In the present study, of 430 patients enrolled in a nationwide registry study who had serum tested for myositis autoantibodies, 374 had either a single specific MSA (n = 253) or no identified MSA (n = 121) and were the subject of the present report. Following univariate analysis, we used random forest classification and exact logistic regression modeling to compare autoantibody subgroups. Anti-p155/140 autoantibodies were the most frequent subgroup, present in 32% of patients with juvenile dermatomyositis (JDM) or overlap myositis with JDM, followed by anti-MJ autoantibodies, which were seen in 20% of JIIM patients, primarily in JDM. Other MSAs, including anti-synthetase, anti-signal recognition particle (SRP), and anti-Mi-2, were present in only 10% of JIIM patients. Features that characterized the anti-p155/140 autoantibody subgroup included Gottron papules, malar rash, "shawl-sign" rash, photosensitivity, cuticular overgrowth, lowest creatine kinase (CK) levels, and a predominantly chronic illness course. The features that differed for patients with anti-MJ antibodies included muscle cramps, dysphonia, intermediate CK levels, a high frequency of hospitalization, and a monocyclic disease course. Patients with anti-synthetase antibodies had higher frequencies of interstitial lung disease, arthralgia, and "mechanic's hands," and had an older age at diagnosis. The anti-SRP group, which had exclusively juvenile polymyositis, was characterized by high

Pathological features of liver tissue in autoantibody-positive chronic hepatitis C patients after plasmaphoresis

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WU Huili

2018-02-01

Full Text Available ObjectiveTo investigate the detection rate and features of autoantibodies in chronic hepatitis C (CHC patients after plasmaphoresis, as well as the liver pathological features of autoantibody-positive CHC patients. MethodsA total of 120 patients who were infected with hepatitis C virus after plasmaphoresis in the Hospital of Dingxi County and Dingxi Hospital of Infectious Diseases from January 1992 to December 1995 were selected as test group; 11 healthy people from the same region were selected as control group. Autoantibody detection was performed for the 120 CHC patients, and liver pathological features were compared between the autoantibody-positive group(n=44 and autoantibody-negative group(n=76 of these patients. The t test was used for comparison of continuous data, and the chi-square test was used for comparison of categorical data. ResultsOf all 120 CHC patients who underwent plasmaphoresis, 44 (36.7% were found to have serum autoantibodies, with antinuclear antibodies as the most common type (21.7%. Compared with the autoantibody-negative group, the autoantibody-positive group had significantly higher scores of focal necrosis inside the hepatic lobules (211±0.88 vs 164±0.88, t=2.349，P=0.021 and ductular reaction inside the portal area (1.86±0.71 vs 1.13±0.66, t=4.217，P＜0.001, as well as a significantly higher rate of interlobular bile duct injury (86.4% vs 55.3%, χ2=12.129，P=0.001. There were no significant differences between the two groups in the degree of liver fibrosis and hepatic steatosis (both P＞0.05. ConclusionAutoantibody-positive are common in CHC patients after plasmaphoresis, and autoantibody-positive patients tend to have more severe injuries of the liver.

Detection of autoantibodies to cytokines

DEFF Research Database (Denmark)

Bendtzen, K; Hansen, M B; Ross, C

2000-01-01

Autoantibodies to various cytokines have been reported in normal individuals and in patients with various infectious and immunoinflammatory disorders, and similar antibodies (Ab) may be induced in patients receiving human recombinant cytokines. The clinical relevance of these Ab is often difficul...

Neuronal Surface Autoantibodies in Neuropsychiatric Disorders: Are There Implications for Depression?

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Shenghua Zong

2017-07-01

Full Text Available Autoimmune diseases are affecting around 7.6–9.4% of the general population. A number of central nervous system disorders, including encephalitis and severe psychiatric disorders, have been demonstrated to associate with specific neuronal surface autoantibodies (NSAbs. It has become clear that specific autoantibodies targeting neuronal surface antigens and ion channels could cause severe mental disturbances. A number of studies have focused or are currently investigating the presence of autoantibodies in specific mental conditions such as schizophrenia and bipolar disorders. However, less is known about other conditions such as depression. Depression is a psychiatric disorder with complex etiology and pathogenesis. The diagnosis criteria of depression are largely based on symptoms but not on the origin of the disease. The question which arises is whether in a subgroup of patients with depression, the symptoms might be caused by autoantibodies targeting membrane-associated antigens. Here, we describe how autoantibodies targeting membrane proteins and ion channels cause pathological effects. We discuss the physiology of these antigens and their role in relation to depression. Finally, we summarize a number of studies detecting NSAbs with a special focus on cohorts that include depression diagnosis and/or show depressive symptoms.

Autoantibodies associated with prenatal and childhood exposure to environmental chemicals in faroese children

DEFF Research Database (Denmark)

Osuna, Christa E; Grandjean, Philippe; Weihe, Pál

2014-01-01

to both neural (neurofilaments, cholineacetyltransferase, astrocyte glial fibrillary acidic protein, and myelin basic protein) and non-neural (actin, desmin, and keratin) antigens were measured and the associations of these autoantibody concentrations with chemical exposures were assessed using linear...... of autoantibodies. However, it is not known if autoantibodies similarly will be generated and detectable in humans following toxicant exposures. Therefore, we conducted a pilot study to investigate if autoantibodies specific for neural and non-neural antigens could be detected in children at age 7 years who have...... been exposed to environmental chemicals. Both prenatal and age-7 exposures to mercury, PCBs, and PFCs were measured in 38 children in the Faroe Islands who were exposed to widely different levels of these chemicals due to their seafood-based diet. Concentrations of IgM and IgG autoantibodies specific...

Anti-C1q autoantibodies in patients with neuromyelitis optica spectrum disorders.

Science.gov (United States)

Yoshikura, Nobuaki; Kimura, Akio; Hayashi, Yuichi; Inuzuka, Takashi

2017-09-15

We examined anti-complement C1q (C1q) autoantibody levels in serum and cerebrospinal fluid (CSF) samples of patients with neuromyelitis optica spectrum disorders (NMOSD). We analyzed the correlations between anti-C1q autoantibody levels and the clinical and other CSF characteristics of NMOSD. Serum and CSF anti-C1q autoantibody levels increased during the acute phase of NMOSD, reverting to the same levels as controls during remission. CSF anti-C1q autoantibody levels during the acute phase correlated with several markers reflecting disease severity, Expanded Disability Status Scale worsening, spinal cord lesion length in cases with myelitis, CSF protein and interleukin-6 levels, and CSF/serum albumin ratios. Copyright © 2017 Elsevier B.V. All rights reserved.

Effect of insulin analogues on insulin/IGF1 hybrid receptors: increased activation by glargine but not by its metabolites M1 and M2.

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Cécile Pierre-Eugene

Full Text Available BACKGROUND: In diabetic patients, the pharmacokinetics of injected human insulin does not permit optimal control of glycemia. Fast and slow acting insulin analogues have been developed, but they may have adverse properties, such as increased mitogenic or anti-apoptotic signaling. Insulin/IGF1 hybrid receptors (IR/IGF1R, present in most tissues, have been proposed to transmit biological effects close to those of IGF1R. However, the study of hybrid receptors is difficult because of the presence of IR and IGF1R homodimers. Our objective was to perform the first study on the pharmacological properties of the five marketed insulin analogues towards IR/IGF1R hybrids. METHODOLOGY: To study the effect of insulin analogues on IR/IGF1R hybrids, we used our previously developed Bioluminescence Resonance Energy Transfer (BRET assay that permits specific analysis of the pharmacological properties of hybrid receptors. Moreover, we have developed a new, highly sensitive BRET-based assay to monitor phophatidylinositol-3 phosphate (PIP(3 production in living cells. Using this assay, we performed a detailed pharmacological analysis of PIP(3 production induced by IGF1, insulin and insulin analogues in living breast cancer-derived MCF-7 and MDA-MB231 cells. RESULTS: Among the five insulin analogues tested, only glargine stimulated IR/IGF1R hybrids with an EC50 that was significantly lower than insulin and close to that of IGF1. Glargine more efficiently stimulated PIP(3 production in MCF-7 cells but not in MDA-MB231 cells as compared to insulin. In contrast, glargine metabolites M1 and M2 showed lower potency for hybrid receptors stimulation, PIP(3 production, Akt and Erk1/2 phosphorylation and DNA synthesis in MCF-7 cells, compared to insulin. CONCLUSION: Glargine, possibly acting through IR/IGF1R hybrids, displays higher potency, whereas its metabolites M1 and M2 display lower potency than insulin for the stimulation of proliferative/anti-apoptotic pathways in

The relationship between procalcitonin and thyroid autoantibodies in patients with autoimmune thyroiditis.

Science.gov (United States)

Oncul, Ali; Ates, Ihsan; Arikan, Mehmet Fettah; Yilmaz, Nisbet; Topcuoglu, Canan; Yilmaz, Fatma Meric; Altay, Mustafa

2017-11-01

The aim of this study is to investigate the serum levels of procalcitonin and its association with autoantibodies in patients with euthyroid Hashimoto's thyroiditis. A total of 80 participants were included in the study; 40 of which were newly diagnosed with Hashimoto's thyroiditis, aged over 18, and 40 of which were healthy volunteers. The serum levels of procalcitonin were measured by enzyme-linked immunosorbent assay kit. Thyroid function tests were analyzed in hormone laboratory with Electro-chemiluminescence immunoassay. Hashimoto's thyroiditis patients had higher median procalcitonin levels than those of the control group (34.3 pg/mL vs 27.8 pg/mL respectively; P=.037). Also, male patients had higher median procalcitonin levels as compared to female patients (37 pg/mL vs 27 pg/mL respectively; P=.013). In the Hashimoto's thyroiditis group, procalcitonin level was positively correlated with anti-thyroglobulin and anti-thyroid peroxidase levels (r=.559, Pthyroid peroxidase levels were identified to be an independent predictor in diagnosis of Hashimoto's thyroiditis. The fact that procalcitonin was found to be correlated with thyroid autoantibodies and found to be an independent risk factor for Hashimoto's thyroiditis in the regression analysis in the framework of this study urges us to think that procalcitonin may be associated with the autoimmunity. © 2017 Wiley Periodicals, Inc.

Cancer biomarkers defined by autoantibody signatures to aberrant O-glycopeptide epitopes

DEFF Research Database (Denmark)

Wandall, Hans H; Blixt, Ola; Tarp, Mads A

2010-01-01

Autoantibodies to cancer antigens hold promise as biomarkers for early detection of cancer. Proteins that are aberrantly processed in cancer cells are likely to present autoantibody targets. The extracellular mucin MUC1 is overexpressed and aberrantly glycosylated in many cancers; thus, we evalua...

Rare myositis-specific autoantibody associations among Hungarian patients with idiopathic inflammatory myopathy.

Science.gov (United States)

Bodoki, L; Nagy-Vincze, M; Griger, Z; Betteridge, Z; Szöllősi, L; Jobanputra, R; Dankó, K

2015-01-01

Idiopathic inflammatory myopathies are systemic, chronic autoimmune diseases characterized by symmetrical, proximal muscle weakness. Homogeneous groups present with similar symptoms. The response to therapy and prognosis could be facilitated by myositis-specific autoantibodies, and in this way, give rise to immunoserological classification. The myositis-specific autoantibodies are directed against specific proteins found in the cytoplasm or in the nucleus of the cells. To date, literature suggests the rarity of the co-existence of two myositis-specific autoantibodies. In this study the authors highlight rare associations of myositis-specific autoantibodies. Three hundred and thirty-seven Hungarian patients with polymyositis or dermatomyositis were studied. Their clinical findings were noted retrospectively. Specific blood tests identified six patients with the rare co-existence of myositis-specific autoantibodies, anti-Jo-1 and anti-SRP, anti-Jo-1 and anti-Mi-2, anti-Mi-2 and anti-PL-12, anti-Mi-2 and anti-SRP, and anti-SRP and anti-PL-7, respectively. This case review aims to identify the clinical importance of these rare associations and their place within the immunoserological classification.

Circulating autoantibodies to phosphorylated α-enolase are a hallmark of pancreatic cancer.

Science.gov (United States)

Tomaino, Barbara; Cappello, Paola; Capello, Michela; Fredolini, Claudia; Sperduti, Isabella; Migliorini, Paola; Salacone, Paola; Novarino, Anna; Giacobino, Alice; Ciuffreda, Libero; Alessio, Massimo; Nisticò, Paola; Scarpa, Aldo; Pederzoli, Paolo; Zhou, Weidong; Petricoin Iii, Emanuel F; Liotta, Lance A; Giovarelli, Mirella; Milella, Michele; Novelli, Francesco

2011-01-07

Pancreatic ductal adenocarcinoma (PDAC) has a dismal prognosis and no diagnostic markers have, as of yet, been defined. In PDAC patients, α-enolase (ENOA) is up-regulated and elicits the production of autoantibodies. Here, we analyzed the autoantibody response to post-translational modifications of ENOA in PDAC patients. ENOA isolated from PDAC tissues and cell lines was characterized by two-dimensional electrophoresis (2-DE) Western blot (WB), revealing the expression of six different isoforms (named ENOA1,2,3,4,5,6) whereas only 4 isoforms (ENOA3,4,5,6) were detectable in normal tissues. As assessed by 2-DE WB, 62% of PDAC patients produced autoantibodies to the two more acidic isoforms (ENOA1,2) as opposed to only 4% of controls. Mass spectrometry showed that ENOA1,2 isoforms were phosphorylated on serine 419. ROC analysis demonstrated that autoantibodies to ENOA1,2 usefully complement the diagnostic performance of serum CA19.9 levels, achieving approximately 95% diagnostic accuracy in both advanced and resectable PDAC. Moreover, the presence of autoantibodies against ENOA1,2 correlated with a significantly better clinical outcome in advanced patients treated with standard chemotherapy. In conclusion, our results demonstrate that ENOA phosphorylation is associated with PDAC and induces specific autoantibody production in PDAC patients that may have diagnostic value.

Clinical utility of anti-p53 auto-antibody: systematic review and focus on colorectal cancer.

Science.gov (United States)

Suppiah, Aravind; Greenman, John

2013-08-07

Mutation of the p53 gene is a key event in the carcinogenesis of many different types of tumours. These can occur throughout the length of the p53 gene. Anti-p53 auto-antibodies are commonly produced in response to these p53 mutations. This review firstly describes the various mechanisms of p53 dysfunction and their association with subsequent carcinogenesis. Following this, the mechanisms of induction of anti-p53 auto-antibody production are shown, with various hypotheses for the discrepancies between the presence of p53 mutation and the presence/absence of anti-p53 auto-antibodies. A systematic review was performed with a descriptive summary of key findings of each anti-p53 auto-antibody study in all cancers published in the last 30 years. Using this, the cumulative frequency of anti-p53 auto-antibody in each cancer type is calculated and then compared with the incidence of p53 mutation in each cancer to provide the largest sample calculation and correlation between mutation and anti-p53 auto-antibody published to date. Finally, the review focuses on the data of anti-p53 auto-antibody in colorectal cancer studies, and discusses future strategies including the potentially promising role using anti-p53 auto-antibody presence in screening and surveillance.

Specific removal of autoantibodies by extracorporeal immunoadsorption ameliorates experimental autoimmune myasthenia gravis.

Science.gov (United States)

Lazaridis, Konstantinos; Dalianoudis, Ioannis; Baltatzidi, Vasiliki; Tzartos, Socrates J

2017-11-15

Myasthenia gravis (MG) is caused by autoantibodies, the majority of which target the muscle acetylcholine receptor (AChR). Plasmapheresis and IgG-immunoadsorption are useful therapy options, but are highly non-specific. Antigen-specific immunoadsorption would remove only the pathogenic autoantibodies, reducing the possibility of side effects while maximizing the benefit. We have extensively characterized such adsorbents, but in vivo studies are missing. We used rats with experimental autoimmune MG to perform antigen-specific immunoadsorptions over three weeks, regularly monitoring symptoms and autoantibody titers. Immunoadsorption was effective, resulting in a marked autoantibody titer decrease while the immunoadsorbed, but not the mock-treated, animals showed a dramatic symptom improvement. Overall, the procedure was found to be efficient, suggesting the subsequent initiation of clinical trials. Copyright © 2017 Elsevier B.V. All rights reserved.

Immunoregulation by naturally occurring and disease-associated autoantibodies

DEFF Research Database (Denmark)

Nielsen, Claus H; Bendtzen, Klaus

2012-01-01

The role of naturally occurring autoantibodies (NAbs) in homeostasis and in disease manifestations is poorly understood. In the present chapter, we review how NAbs may interfere with the cytokine network and how NAbs, through formation of complement-activating immune complexes with soluble self......-antigens, may promote the uptake and presentation of self-molecules by antigen-presenting cells. Both naturally occurring and disease-associated autoantibodies against a variety of cytokines have been reported, including NAbs against interleukin (IL)-1α, IL-6, IL-8, IL-10, granulocyte-macrophage colony...

Radioreceptor assay for somatomedin A

Energy Technology Data Exchange (ETDEWEB)

Takano, K [Tokyo Women' s Medical Coll. (Japan)

1975-04-01

Measurement method of somatomedian A by radioreceptor assay using the human placenta membrane was described and discussed. Binding rate of /sup 125/I-somatomedin A to its receptors was studied under various conditions of time and temperature of the incubation, and pH of the system. The influence of somatomedin A, porcine insulin, and porcine calcitonin, on /sup 125/I-somatomedin A bound receptors was studied, and these hormones showed the competitive binding to somatomedin A receptors in some level. The specificity, recovery rate, and clinical applications of somatomedin A were also discussed. Radioreceptor assay for somatomedine A provided easier, faster, and more accurate measurements than conventional bioassay. This technique would be very useful to study somatomedin A receptor and functions of insulin.

Rheumatic Disease Autoantibodies in Patients with Autoimmune Thyroid Diseases.

Science.gov (United States)

Nisihara, Renato; Pigosso, Yasmine; Prado, Nathalia; Utiyama, Shirley R R; Carvalho, Gisah; Skare, Thelma

2018-06-04

Patients with autoimmune thyroid diseases (ATD) such as Graves' disease (GD) and Hashimoto thyroiditis (HT) may have non-organ specific autoantibodies such as ANA (antinuclear antibodies) and RF (rheumatoid factor). To study the prevalence of rheumatic autoantibodies in a group of ATD patients without known rheumatic diseases and to evaluate its association with the patients' epidemiological and treatment profile. To follow positive non-organ specific autoantibody-positive ATD individuals to investigate whether they will develop a rheumatic disorder. A sample of 154 ATD patients (70 HT and 84 GD; mean age 45.3 ± 14.2) had determination of ANA by immunofluorescence, using hep-2 cells as substrate, extractable nuclear antigen (ENA) profile by ELISA kits and RF by latex agglutination. Epidemiological and treatment profile were obtained through chart review. These patients were followed for the mean period of five years, between 2010 to 2015. Positive ANA was found in 17.5% (27/154) of the patients: anti-Ro/SS-A in 4/154 (2.5%); anti-RNP in 4/154 (2.5%) and anti-La/SS-B in 3/154 (1.9%). None had anti-Sm antibodies. RF was detected in 12/154 (7.7%) of ATD patients and was more common in older individuals (p = 0.007). There was a positive association between the presence of RF and ANA (p = 0.03; OR = 3.89; 95% CI = 1.1-13.3). None of the patients with positive autoantibodies developed clinical rheumatic diseases during the period of observation. We found rheumatic autoantibodies in 17.5% of ATD patients without rheumatic diseases. None of them were associated with the appearance of clinical rheumatic disorder during the period of five years. ©2018The Author(s). Published by S. Karger AG, Basel.

Autoantibodies and human immunodeficiency viruses infection: a case-control study.

Science.gov (United States)

Chretien, P; Monier, J C; Oksman, F; San Marco, M; Escande, A; Goetz, J; Cohen, J; Baquey, A; Humbel, R L; Sibilia, J

2003-01-01

To determine the prevalence of organ-specific and non-specific autoantibodies in HIV-infected patients. A multicentric collaborative case-control study including 105 HIV patients and 100 sex- and age-matched HIV-negative healthy volunteers. Antinuclear, anti-ds DNA, anti-histone, anti-Sm, rheumatoid factor(IgM), anti-beta 2 glycoprotein 1, antineutrophil cytoplasmic, anti-LKM1, anti-LCA1, anti-gastric parietal cell, antiplatelet, anti-intermediate filament, anti-mitotic spindle apparatus, anti-Golgi, anti-ribosome and anti-thyroid autoantibodies were screened in six European laboratories. Only IgG and IgM anticardiolipin, IgG antiplatelet, anti-smooth muscle and anti-thyroglobulin antibodies were statistically more frequent in HIV patients. There was no correlation with the numbers of CD4+ cells except in the case of anti-smooth muscle antibodies. We were unable to find specific autoantibodies such as anti-ds DNA, anti-Sm, AMA, anti-LKM1, anti-LCA1 or anti-beta 2 GP1 antibodies in these patients. Our results indicate that the autoantibody profile of HIV infections is comparable to those of other chronic viral infections. HIV does not seem to be more autoimmunogenic than other viruses.

Production of Autoantibodies in Chronic Hepatitis B Virus Infection Is Associated with the Augmented Function of Blood CXCR5+CD4+ T Cells.

Directory of Open Access Journals (Sweden)

Yu Lei

Full Text Available T follicular helper cells (Tfh provide help to B cells to support their activation, expansion and differentiation. However, the role of Tfh cells in chronic HBV infection is poorly defined. The aim of this research was to examine the function of Tfh cells and whether they are involved in HBV related disease. Blood CXCR5+CD4+T cells and B cells in 85 patients with chronic HBV infection (HBV patients and health controls (HC were examined by flow cytometry. The molecule expression in blood CXCR5+CD4+ T cells was detected by real-time PCR. Blood CXCR5+CD4+ T cells and B cells were co-cultured and the production of Ig and cytokines was detected by ELISA. Autoantibodies were detected by indirect immunofluorescence and immunospot assay. We found that blood CXCR5+CD4+ T cells in patients with chronic HBV infection (HBV patients expressed higher level of activation related molecules and cytokines than that from health controls (HC.In HBV patients, the frequency of blood CXCR5+CD4+ T cells was significantly correlated with serum ALT and AST. We also found that blood CXCR5+CD4+ T cells from HBV patients could induce B cells to secret higher level of immunoglobulin than that from HC. Several autoantibodies, including ANA, ss-A, ss-B, Scl-70, Jo-1, ect, were indeed positive in 65% HBV patients. Among HBV patients, expression of function related molecules was significantly higher in blood CXCR5+CD4+ T cells from patients with autoantibodies than that without autoantibodies. Our research indicated that blood CXCR5+CD4+ T cells from HBV patients were over activated and show augmented capacity to help B cells for antibody secreting, which might correlated with liver inflammation and the production of autoantibodies in extrahepatic manifestations.

Learning From Past Failures of Oral Insulin Trials.

Science.gov (United States)

Michels, Aaron W; Gottlieb, Peter A

2018-07-01

Very recently one of the largest type 1 diabetes prevention trials using daily administration of oral insulin or placebo was completed. After 9 years of study enrollment and follow-up, the randomized controlled trial failed to delay the onset of clinical type 1 diabetes, which was the primary end point. The unfortunate outcome follows the previous large-scale trial, the Diabetes Prevention Trial-Type 1 (DPT-1), which again failed to delay diabetes onset with oral insulin or low-dose subcutaneous insulin injections in a randomized controlled trial with relatives at risk for type 1 diabetes. These sobering results raise the important question, "Where does the type 1 diabetes prevention field move next?" In this Perspective, we advocate for a paradigm shift in which smaller mechanistic trials are conducted to define immune mechanisms and potentially identify treatment responders. The stage is set for these interventions in individuals at risk for type 1 diabetes as Type 1 Diabetes TrialNet has identified thousands of relatives with islet autoantibodies and general population screening for type 1 diabetes risk is under way. Mechanistic trials will allow for better trial design and patient selection based upon molecular markers prior to large randomized controlled trials, moving toward a personalized medicine approach for the prevention of type 1 diabetes. © 2018 by the American Diabetes Association.

Cyclodextrin-insulin complex encapsulated polymethacrylic acid based nanoparticles for oral insulin delivery.

Science.gov (United States)

Sajeesh, S; Sharma, Chandra P

2006-11-15

Present investigation was aimed at developing an oral insulin delivery system based on hydroxypropyl beta cyclodextrin-insulin (HPbetaCD-I) complex encapsulated polymethacrylic acid-chitosan-polyether (polyethylene glycol-polypropylene glycol copolymer) (PMCP) nanoparticles. Nanoparticles were prepared by the free radical polymerization of methacrylic acid in presence of chitosan and polyether in a solvent/surfactant free medium. Dynamic light scattering (DLS) experiment was conducted with particles dispersed in phosphate buffer (pH 7.4) and size distribution curve was observed in the range of 500-800 nm. HPbetaCD was used to prepare non-covalent inclusion complex with insulin and complex was analyzed by Fourier transform infrared (FTIR) and fluorescence spectroscopic studies. HPbetaCD complexed insulin was encapsulated into PMCP nanoparticles by diffusion filling method and their in vitro release profile was evaluated at acidic/alkaline pH. PMCP nanoparticles displayed good insulin encapsulation efficiency and release profile was largely dependent on the pH of the medium. Enzyme linked immunosorbent assay (ELISA) study demonstrated that insulin encapsulated inside the particles was biologically active. Trypsin inhibitory effect of PMCP nanoparticles was evaluated using N-alpha-benzoyl-L-arginine ethyl ester (BAEE) and casein as substrates. Mucoadhesive studies of PMCP nanoparticles were conducted using freshly excised rat intestinal mucosa and the particles were found fairly adhesive. From the preliminary studies, cyclodextrin complexed insulin encapsulated mucoadhesive nanoparticles appear to be a good candidate for oral insulin delivery.

Characterization and potential clinical applications of autoantibodies against cytokines

DEFF Research Database (Denmark)

de Lemos Rieper, Carina; Galle, Pia; Hansen, Morten Bagge

2009-01-01

Autoantibodies recognizing cytokines arise in certain patients during the course of therapy with recombinant cytokines, although they may arise spontaneously as well. They are typically high avidity and in vitro neutralizing IgG antibodies present in picomolar to nanomolar concentrations. Methodo......Autoantibodies recognizing cytokines arise in certain patients during the course of therapy with recombinant cytokines, although they may arise spontaneously as well. They are typically high avidity and in vitro neutralizing IgG antibodies present in picomolar to nanomolar concentrations...

Chitosan nanofibers for transbuccal insulin delivery.

Science.gov (United States)

Lancina, Michael G; Shankar, Roopa Kanakatti; Yang, Hu

2017-05-01

In this work, they aimed at producing chitosan based nanofiber mats capable of delivering insulin via the buccal mucosa. Chitosan was electrospun into nanofibers using poly(ethylene oxide) (PEO) as a carrier molecule in various feed ratios. The mechanical properties and degradation kinetics of the fibers were measured. Insulin release rates were determined in vitro using an ELISA assay. The bioactivity of released insulin was measured in terms of Akt activation in pre-adipocytes. Insulin permeation across the buccal mucosa was measured in an ex-vivo porcine transbuccal model. Fiber morphology, mechanical properties, and in vitro stability were dependent on PEO feed ratio. Lower PEO content blends produced smaller diameter fibers with significantly faster insulin release kinetics. Insulin showed no reduction in bioactivity due to electrospinning. Buccal permeation of insulin facilitated by high chitosan content blends was significantly higher than that of free insulin. Taken together, the work demonstrates that chitosan-based nanofibers have the potential to serve as a transbuccal insulin delivery vehicle. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 1252-1259, 2017. © 2017 Wiley Periodicals, Inc.

Identification of residues in the insulin molecule important for binding to insulin-degrading enzyme

Energy Technology Data Exchange (ETDEWEB)

Affholter, J.A.; Roth, R.A. (Stanford Univ. School of Medicine, CA (USA)); Cascieri, M.A.; Bayne, M.L. (Merck Sharp and Dohme Research Labs., Rahway, NJ (USA)); Brange, J. (Novo Research Institute, Bagsvaerd (Denmark)); Casaretto, M. (Deutsches Wollforschungsinstitut an der Technischen, Aachen (West Germany))

1990-08-21

Insulin-degrading enzyme (IDE) hydrolyzes insulin at a limited number of sites. Although the positions of these cleavages are known, the residues of insulin important in its binding to IDE have not been defined. To this end, the authors have studied the binding of a variety of insulin analogues to the protease in a solid-phase binding assay using immunoimmobilized IDE. Since IDE binds insulin with 600-fold greater affinity than it does insulin-like growth factor, the first set of analogues studied were hybrid molecules of insulin and IGF I. Removal of the eight amino acid D-chain region of IGF I (which has been predicted to interfere with binding to the 23-25 region) results in a 25-fold increase in affinity for IDE, confirming the importance of residues 23-25 in the high-affinity recognition of IDE. A similar role for the corresponding (B24-26) residues of insulin is supported by the use of site-directed mutant and semisynthetic insulin analogues. Insulin mutants (B25-Asp)insulin and (B25-His)insulin display 16- and 20-fold decreases in IDE affinity versus wild-type insulin. Similar decreases in affinity are observed with the C-terminal truncation mutants (B1-24-His{sup 25}-NH{sub 2})insulin and (B1-24-Leu{sup 25}-NH{sub 2})insulin, but not (B1-24-Trp{sup 25}-NH{sub 2})insulin and (B1-24-Tyr{sup 25}-NH{sub 2})insulin. The truncated analogue with the lowest affinity for IDE ((B1-24-His{sup 25}-NH{sub 2})insulin) has one of the highest affinities for the insulin receptor. Therefore, they have identified a region of the insulin molecule responsible for its high-affinity interaction with IDE. Although the same region has been implicated in the binding of insulin to its receptor, the data suggest that the structural determinants required for binding to receptor and IDE differ.

Identification of residues in the insulin molecule important for binding to insulin-degrading enzyme

International Nuclear Information System (INIS)

Affholter, J.A.; Roth, R.A.; Cascieri, M.A.; Bayne, M.L.; Brange, J.; Casaretto, M.

1990-01-01

Insulin-degrading enzyme (IDE) hydrolyzes insulin at a limited number of sites. Although the positions of these cleavages are known, the residues of insulin important in its binding to IDE have not been defined. To this end, the authors have studied the binding of a variety of insulin analogues to the protease in a solid-phase binding assay using immunoimmobilized IDE. Since IDE binds insulin with 600-fold greater affinity than it does insulin-like growth factor, the first set of analogues studied were hybrid molecules of insulin and IGF I. Removal of the eight amino acid D-chain region of IGF I (which has been predicted to interfere with binding to the 23-25 region) results in a 25-fold increase in affinity for IDE, confirming the importance of residues 23-25 in the high-affinity recognition of IDE. A similar role for the corresponding (B24-26) residues of insulin is supported by the use of site-directed mutant and semisynthetic insulin analogues. Insulin mutants [B25-Asp]insulin and [B25-His]insulin display 16- and 20-fold decreases in IDE affinity versus wild-type insulin. Similar decreases in affinity are observed with the C-terminal truncation mutants [B1-24-His 25 -NH 2 ]insulin and [B1-24-Leu 25 -NH 2 ]insulin, but not [B1-24-Trp 25 -NH 2 ]insulin and [B1-24-Tyr 25 -NH 2 ]insulin. The truncated analogue with the lowest affinity for IDE ([B1-24-His 25 -NH 2 ]insulin) has one of the highest affinities for the insulin receptor. Therefore, they have identified a region of the insulin molecule responsible for its high-affinity interaction with IDE. Although the same region has been implicated in the binding of insulin to its receptor, the data suggest that the structural determinants required for binding to receptor and IDE differ

Red cell autoantibodies characterized by competitive inhibition of iodine 125 Rh alloantibody binding and by immunoprecipitation of membrane proteins

International Nuclear Information System (INIS)

Pierce, S.W.; Victoria, E.J.; Masouredis, S.P.

1990-01-01

The relationship between determinants recognized by warm-type immunoglobulin G red cell autoantibodies and the Rh antigens was characterized by autoantibody competitive inhibition of iodine 125 Rh alloantibody binding and autoantibody immunoprecipitation of iodine 125 red blood cell membrane proteins. The majority of blood donor autoantibody recognized epitopes that are closely related to Rh antigens as determined by competitive inhibition studies. Eighteen of 20 (90%) autoantibodies inhibited anti-Rh(c) binding, 15 inhibited anti-Rh(E), 5 inhibited anti-Rh(D), and only 2 failed to inhibit any of the three Rh alloantibodies tested. Autoantibodies that inhibited anti-Rh(D) also inhibited anti-Rh(c) and anti-Rh(E) and all those that inhibited anti-Rh(E) also inhibited anti-Rh(c). Autoantibodies that inhibited all three Rh alloantibodies immunoprecipitated 30 kd membrane polypeptides, as did two of the three autoantibodies that inhibited only anti-Rh(c) and anti-Rh(E). One autoantibody in this group and two autoantibodies that inhibited only anti-Rh(c), as well as an autoantibody that did not inhibit any of the Rh alloantibodies, immunoprecipitated only a single membrane polypeptide identified as band 3. The majority of normal donor red blood cell autoantibodies inhibited the binding of Rh alloantibodies, which indicates that they either bound to the Rh polypeptides or to epitopes on band 3 that were closely associated with the Rh complex

Heterogeneity of human plasma insulin: techniques for separating immunoreactive components and their determination by radioimmunoassay

International Nuclear Information System (INIS)

Souza, Iracelia Torres de Toledo e

1977-01-01

When human plasma is filtered on Sephadex G-SO fine, insulin immunoreactivity is recovered in two peaks: 'big insulin', the higher molecular weight component and 'little insulin', the lower molecular component, having elution volumes that correspond to those of porcine proinsulin 125 I and porcine insulin 125 I respectively. The presence of another form of immunoreactive insulin 'big big insulin' was detected from an insuloma suspect and its elution pattern corresponding to serum albumin. The eluates correspondent to 'big' and 'little' insulin as well as 'big big' component were assayed by radioimmunoassay using crystalline human insulin as a standard, porcine insulin 125 tracer and anti insulin serum. The antibody, raised in guinea-pigs, was sensitive and potent being adequate for the assay. The reactivity of insulin and proinsulin was tested against the antibody. The relative proportions of several components of total immunoreactive insulin in plasma were studied in basal conditions in five normal subjects and in the patient JSC with pancreatic insulin-secreting tumor as well as after glucose stimuli in all tolbutamide in JSC. (author)

[Significance of non-organ-specific autoantibodies in HCV-related chronic hepatitis].

Science.gov (United States)

Guidi, Marcello; Muratori, Paolo; Granito, Alessandro; Muratori, Luigi; Pappas, Georgios; Bianchi, Francesco B

2005-12-01

The preliminary question regarding the clinical issue of the antiviral therapy in the HCV related chronic hepatitis patients is: is it mandatory the research for the autoantibodies in the eligible patients for the antiviral treatment? This issue is of particular interest at the light of the the reported cases of HCV positive patients with positivity for liver kidney microsome type 1 antibody who developed a hepatitic flare during the antiviral treatment. The data from literature about the efficacy and safety on the antiviral treatment in patients with autoantibodies are few and controversial, particularly if the ones regarding antiviral drugs and more recent treatment regimens are taking into account (peg-interferon, combined therapy of interferon and ribavirin). Large and prospective studies are needed for a thorough evaluation about the potential impact of autoantibodies reactivity on the therapeutic outcome. To date, it must be confirmed that a strict monitoring of hepatic parameters is to recommend during the whole treatment phase. This in the light of a potential appearance of significant flares of aminotransferases, particularly in subjects with anti LKM-1 autoantibodies, during interferon therapy.

The Emerging Importance of Non-HLA Autoantibodies in Kidney Transplant Complications.

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Cardinal, Héloise; Dieudé, Mélanie; Hébert, Marie-Josée

2017-02-01

Antibodies that are specific to organ donor HLA have been involved in the majority of cases of antibody-mediated rejection in solid organ transplant recipients. However, recent data show that production of non-HLA autoantibodies can occur before transplant in the form of natural autoantibodies. In contrast to HLAs, which are constitutively expressed on the cell surface of the allograft endothelium, autoantigens are usually cryptic. Tissue damage associated with ischemia-reperfusion, vascular injury, and/or rejection creates permissive conditions for the expression of cryptic autoantigens, allowing these autoantibodies to bind antigenic targets and further enhance vascular inflammation and renal dysfunction. Antiperlecan/LG3 antibodies and antiangiotensin II type 1 receptor antibodies have been found before transplant in patients with de novo transplants and portend negative long-term outcome in patients with renal transplants. Here, we review mounting evidence suggesting an important role for autoantibodies to cryptic antigens as novel accelerators of kidney dysfunction and acute or chronic allograft rejection. Copyright © 2017 by the American Society of Nephrology.

Increasing ICA512 autoantibody titers predict development of abnormal oral glucose tolerance tests.

Science.gov (United States)

Sanda, Srinath

2018-03-01

Determine if autoantibody titer magnitude and variability predict glucose abnormalities in subjects at risk for type 1 diabetes. Demographic information, longitudinal autoantibody titers, and oral glucose tolerance test (OGTT) data were obtained from the TrialNet Pathway to Prevention study. Subjects (first and second degree relatives of individuals with type 1 diabetes) with at least 2 diabetes autoantibodies were selected for analysis. Autoantibody titer means were calculated for each subject for the duration of study participation and the relationship between titer tertiles and glucose value tertiles from OGTTs (normal, impaired, and diabetes) was assessed with a proportional odds ordinal regression model. A matched pairs analysis was used to examine the relationship between changes in individual autoantibody titers and 120-minute glucose values. Titer variability was quantified using cumulative titer standard deviations. We studied 778 subjects recruited in the TrialNet Pathway to Prevention study between 2006 and 2014. Increased cumulative mean titer values for both ICA512 and GAD65 (estimated increase in proportional odds = 1.61, 95% CI = 1.39, 1.87, P < 1 × 10 -9 and 1.17, 95% CI = 1.03, 1.32, P = .016, respectively) were associated with peak 120-minute glucose values. While fluctuating titer levels were observed in some subjects, no significant relationship between titer standard deviation and glucose values was observed. ICA512 autoantibody titers associate with progressive abnormalities in glucose metabolism in subjects at risk for type 1 diabetes. Fluctuations in autoantibody titers do not correlate with lower rates of progression to clinical disease. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Identification of residues in the insulin molecule important for binding to insulin-degrading enzyme.

Science.gov (United States)

Affholter, J A; Cascieri, M A; Bayne, M L; Brange, J; Casaretto, M; Roth, R A

1990-08-21

Insulin-degrading enzyme (IDE) hydrolyzes insulin at a limited number of sites. Although the positions of these cleavages are known, the residues of insulin important in its binding to IDE have not been defined. To this end, we have studied the binding of a variety of insulin analogues to the protease in a solid-phase binding assay using immunoimmobilized IDE. Since IDE binds insulin with 600-fold greater affinity than it does insulin-like growth factor I (25 nM and approximately 16,000 nM, respectively), the first set of analogues studied were hybrid molecules of insulin and IGF I. IGF I mutants [insB1-17,17-70]IGF I, [Tyr55,Gln56]IGF I, and [Phe23,Phe24,Tyr25]IGF I have been synthesized and share the property of having insulin-like amino acids at positions corresponding to primary sites of cleavage of insulin by IDE. Whereas the first two exhibit affinities for IDE similar to that of wild type IGF I, the [Phe23,Phe24,Tyr25]IGF I analogue has a 32-fold greater affinity for the immobilized enzyme. Replacement of Phe-23 by Ser eliminates this increase. Removal of the eight amino acid D-chain region of IGF I (which has been predicted to interfere with binding to the 23-25 region) results in a 25-fold increase in affinity for IDE, confirming the importance of residues 23-25 in the high-affinity recognition of IDE. A similar role for the corresponding (B24-26) residues of insulin is supported by the use of site-directed mutant and semisynthetic insulin analogues. Insulin mutants [B25-Asp]insulin and [B25-His]insulin display 16- and 20-fold decreases in IDE affinity versus wild-type insulin.(ABSTRACT TRUNCATED AT 250 WORDS)

Neuronal autoantibodies in epilepsy patients with peri-ictal autonomic findings.

Science.gov (United States)

Baysal-Kirac, Leyla; Tuzun, Erdem; Erdag, Ece; Ulusoy, Canan; Vanli-Yavuz, Ebru Nur; Ekizoglu, Esme; Peach, Sian; Sezgin, Mine; Bebek, Nerses; Gurses, Candan; Gokyigit, Aysen; Vincent, Angela; Baykan, Betul

2016-03-01

Autonomic dysfunction has frequently been reported in autoimmune encephalitis associated with seizures and there is growing evidence that epilepsy patients may display neuronal autoantibodies (NAAb). The aim of this study was to investigate the frequency of NAAb in epilepsy patients with peri-ictal autonomic findings. Fifty-eight patients (37 women/21 men; average age of 34.2 ± 9.9 years and epilepsy duration of 19.1 ± 9.6 years) who had at least one video-EEG recorded focal or secondary generalized seizure with clear-cut documented peri-ictal autonomic findings, or consistently reported seizures with autonomic semiology, were included. NAAb were tested by RIA or cell based assays. NAAb were present in 17 of 58 (29.3%) patients. Among seropositive patients, antibodies were directed against N-methyl-D-aspartate receptor (NMDAR) in 5 (29%), contactin-associated protein-like 2 (CASPR2) in 5 (29%), uncharacterized voltage gated potassium channel (VGKC)-complex antigens in 3 (18%), glutamic acid decarboxylase (GAD) in 2 (12%), glycine receptor (GLYR) in one (6%) and type A gamma aminobutyric acid receptor (GABAAR) in one patient (6%). Peri-ictal gastrointestinal manifestations, piloerection, ictal fever, urinary urge, and cough occurred more commonly in the seropositive group. The prevalences of psychotic attacks and status epilepticus were significantly increased in the seropositive group. Seropositivity prevalence in our patient group with peri-ictal autonomic findings is higher than other previously reported epilepsy cohorts. In our study, ictal fever-VGKC-complex antibody and pilomotor seizure-GABAAR antibody associations were documented for the first time. Chronic epilepsy patients with peri-ictal autonomic semiology, history of status epilepticus and psychotic disorder may benefit from autoantibody screening.

Enzyme-linked immunosorbent assays for insulin-like growth factor-I using six-histidine tag fused proteins

International Nuclear Information System (INIS)

Huang Yong; Shi Ruina; Zhong Xuefei; Wang Dan; Zhao Meiping; Li Yuanzong

2007-01-01

The fusion proteins of insulin-like growth factor-I (IGF-I) and six-histidine tag (IGF-I-6H, 6H-IGF-I-6H) were cloned, expressed, purified and renatured, with their immunoreaction properties and biological activities intact. The binding kinetics between these fusion proteins and anti-IGF-I antibody or anti-6H antibody were studied using surface plasmon resonance (SPR). Two enzyme-linked immunosorbent assay (ELISA) modes, which proved feasible in the measurement of human serum samples, were used to detect IGF-I with the help of the six-histidine tagged proteins. Furthermore, combining the production technique of the six-histidine tagged fusion protein with the competitive sandwich ELISA mode, using an enzyme labeled anti-6H antibody as a tracer, can be a universal immunochemical method to quantitate other polypeptides or proteins

Intracellular insulin-receptor dissociation and segregation in a rat fibroblast cell line transfected with a human insulin receptor gene

International Nuclear Information System (INIS)

Levy, J.R.; Olefsky, J.M.

1988-01-01

The cellular processing of insulin and insulin receptors was studied using a rat fibroblast cell line that had been transfected with a normal human insulin receptor gene, expressing approximately 500 times the normal number of native fibroblasts insulin receptors. These cells bind and internalize insulin normally. Biochemically assays based on the selective precipitation by polyethylene glycol of intact insulin-receptor complexes but not of free intracellular insulin were developed to study the time course of intracellular insulin-receptor dissociation. Fibroblasts were incubated with radiolabeled insulin at 4 0 C, and internalization of insulin-receptor complexes was initiated by warming the cells to 37 0 C. Within 2 min, 90% of the internalized radioactivity was composed of intact insulin-receptor complexes. The dissociation of insulin from internalized insulin-receptor complexes was markedly inhibited by monensin and chloroquine. Furthermore, chloroquine markedly increased the number of cross-linkable intracellular insulin-receptor complexes, as analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis autoradiography. These findings suggest that acidification of intracellular vesicles is responsible for insulin-receptor dissociation. Physical segregation of dissociated intracellular insulin from its receptor was monitored. The results are consistent with the view that segregation of insulin and receptor occurs 5-10 min after initiation of dissociation. These studies demonstrate the intracellular itinerary of insulin-receptor complexes, including internalization, dissociation of insulin from the internalized receptor within an acidified compartment, segregation of insulin from the receptor, and subsequent ligand degradation

Severe hypoglycemia secondary to methimazole-induced insulin autoimmune syndrome in a 16 year old African-American male.

Science.gov (United States)

Gomez Cruz, Michelle J; Jabbar, Muhammad; Saini, Natinder; Eng, Donna; Crawford, Brandon; Vazquez, Delia M; Menon, Ram; Chen, Ming

2012-12-01

Insulin autoimmune syndrome (IAS) or Hirata's disease is a rare disorder characterized by hypoglycemia secondary to insulin autoantibodies (IAb). Over 200 patients have been described from Japan with significantly less numbers being reported from outside the Orient. IAS is more common in patients older than 40 yr of age with reports in the pediatric age group being notably rarer. Exposure to sulfhydryl group containing medications is implicated in the pathogenesis of this syndrome. In this report, we describe a case of IAS in an African-American adolescent. A 16-yr-old healthy African-American male was diagnosed with Graves' disease and started on Methimazole. Four weeks later, he was found unconscious and hypoglycemic (blood sugar 1.5 mmol/L). Evaluation was negative for insulinoma. Insulin antibodies were positive. Oral glucose tolerance test revealed elevated free insulin concentrations with disproportionately elevated total insulin levels. The patient was started on prednisone, diazoxide, and propranolol for management of IAS and hyperthyroidism. Thyroid radio-ablation was subsequently undertaken. The doses of prednisone and diazoxide were tapered and these medications discontinued after 9 months. The insulin antibody levels decreased gradually and became undetectable in 6 months with resolution of the hypoglycemia. © 2012 John Wiley & Sons A/S.

Thyroid Autoantibodies Display both “Original Antigenic Sin” and Epitope Spreading

OpenAIRE

McLachlan, Sandra M.; Rapoport, Basil

2017-01-01

Evidence for original antigenic sin in spontaneous thyroid autoimmunity is revealed by autoantibody interactions with immunodominant regions on thyroid autoantigens, thyroglobulin (Tg), thyroid peroxidase (TPO), and the thyrotropin receptor (TSHR) A-subunit. In contrast, antibodies induced by immunization of rabbits or mice recognize diverse epitopes. Recognition of immunodominant regions persists despite fluctuations in autoantibody levels following treatment or over time. The enhancement of...

Thyroglobulin (Tg) recovery testing with quantitative Tg antibody measurement for determining interference in serum Tg assays in differentiated thyroid carcinoma

NARCIS (Netherlands)

Persoon, ACM; Links, TP; Wilde, J; Sluiter, WJ; Wolffenbuttel, BHR; van den Ouweland, JMW

Background: Thyroglobulin (Tg) measurements are complicated by interference from Tg autoantibodies (TgAbs) or heterophilic antibodies (HAMAs). We used a new automated immunochemiluminometric assay (ICMA) with Tg recovery (TgR) on the Nichols Advantage (R) platform to reassess the clinical utility of

Insulin-egg yolk dispersions in self microemulsifying system.

Science.gov (United States)

Singnurkar, P S; Gidwani, S K

2008-11-01

Formulation of insulin into a microemulsion very often presents a physicochemical instability during their preparation and storage. In order to overcome this lack of stability and facilitate the handling of these colloidal systems, stabilization of insulin in presence of hydrophobic components of a microemulsion appears as the most promising strategy. The present paper reports the use of egg yolk for stabilization of insulin in self microemulsifying dispersions. Insulin loaded egg yolk self microemulsifying dispersions were prepared by lyophilization followed by dispersion into self microemulsifying vehicle. The physicochemical characterization of selfmicroemulsifying dispersions includes such as insulin encapsulation efficiency, in vitro stability of insulin in presence of proteolytic enzymes and in vitro release. The biological activity of insulin from the dispersion was estimated by enzyme-linked immunosorbant assay and in vivo using Wistar diabetic rats. The particle size ranged 1.023±0.316 μm in diameter and insulin encapsulation efficiency was 98.2±0.9 %. Insulin hydrophobic self microemulsifying dispersions suppressed insulin release in pH 7.4 phosphate buffer and shown to protect insulin from enzymatic degradation in vitro in presence of chymotripsin. Egg yolk encapsulated insulin was bioactive, demonstrated through both in vivo and in vitro.

Female Infertility and Serum Auto-antibodies: a Systematic Review.

Science.gov (United States)

Deroux, Alban; Dumestre-Perard, Chantal; Dunand-Faure, Camille; Bouillet, Laurence; Hoffmann, Pascale

2017-08-01

On average, 10 % of infertile couples have unexplained infertility. Auto-immune disease (systemic lupus erythematosus, anti-phospholipid syndrome) accounts for a part of these cases. In the last 20 years, aspecific auto-immunity, defined as positivity of auto-antibodies in blood sample without clinical or biological criteria for defined diseases, has been evoked in a subpopulation of infertile women. A systematic review was performed (PUBMED) using the MESH search terms "infertility" and "auto-immunity" or "reproductive technique" or "assisted reproduction" or "in vitro fertilization" and "auto-immunity." We retained clinical and physiopathological studies that were applicable to the clinician in assuming joint management of both infertility associated with serum auto-antibodies in women. Thyroid auto-immunity which affects thyroid function could be a cause of infertility; even in euthyroidia, the presence of anti-thyroperoxydase antibodies and/or thyroglobulin are related to infertility. The presence of anti-phospholipid (APL) and/or anti-nuclear (ANA) antibodies seems to be more frequent in the population of infertile women; serum auto-antibodies are associated with early ovarian failure, itself responsible for fertility disorders. However, there exist few publications on this topic. The methods of dosage, as well as the clinical criteria of unexplained infertility deserve to be standardized to allow a precise response to the question of the role of serum auto-antibodies in these women. The direct pathogenesis of this auto-immunity is unknown, but therapeutic immunomodulators, prescribed on a case-by-case basis, could favor pregnancy even in cases of unexplained primary or secondary infertility.

A modified direct insulin lodination for insulin radioreceptor assay in human erythrocytes

Energy Technology Data Exchange (ETDEWEB)

Elnabrawie, F S; Megahed, Y M; Fahim, F A; Ahmed, A M [Middle Eastern Regional radioisotope center for Arab Countries biochemistry dept. Faculty of science Ain Shams university, cairo, (Egypt)

1995-10-01

A substitution of iodine in to the inulin molecule will easily lead to a decreased hormonal activity. Nevertheless it cannot be concluded without further investigation that one or several of the tyrosyl groups are directly involve in the degree of iodination and the loss activity has been demonstrated by many workers, (Frenkel-Conrat 1950, and de Zoeten and van Strik, 1961). On the basis of the Frenkel-Conrat experiments, lee 1957 suggested that a mono-substitution of iodine in two tyrosyl groups is possible without loss of biological activity. In general, iodination is easy to perform as usually carried out at room temperature at PH of 7.5 in a phosphate buffer medium (Megahed et al., 1976, 1979). Reaction between antigen and antibody in radioimmunoassay (RIA), immunoradiometric assay (IRMA) and radioreceptor assay (RRA), is detected by radiation emitted from a radioisotope incorporated into the antigen or antibody molecule. Ideally the radiolabelled molecule has an immunoreactivity identical to the natural molecule and this behaves in the same way as in the assay procedure. Oxidation of 125 I-iodide gives rise to the 125 I-iodination which in a mildly alkaline PH (7.5) reacts with the phenolic benzene ring of tyrosine and tyrosyl residues by a process of electrophilic attack.

A modified direct insulin lodination for insulin radioreceptor assay in human erythrocytes

International Nuclear Information System (INIS)

Elnabrawie, F.S.; Megahed, Y.M.; Fahim, F.A.; Ahmed, A.M.

1995-01-01

A substitution of iodine in to the inulin molecule will easily lead to a decreased hormonal activity. Nevertheless it cannot be concluded without further investigation that one or several of the tyrosyl groups are directly involve in the degree of iodination and the loss activity has been demonstrated by many workers, (Frenkel-Conrat 1950, and de Zoeten and van Strik, 1961). On the basis of the Frenkel-Conrat experiments, lee 1957 suggested that a mono-substitution of iodine in two tyrosyl groups is possible without loss of biological activity. In general, iodination is easy to perform as usually carried out at room temperature at PH of 7.5 in a phosphate buffer medium (Megahed et al., 1976, 1979). Reaction between antigen and antibody in radioimmunoassay (RIA), immunoradiometric assay (IRMA) and radioreceptor assay (RRA), is detected by radiation emitted from a radioisotope incorporated into the antigen or antibody molecule. Ideally the radiolabelled molecule has an immunoreactivity identical to the natural molecule and this behaves in the same way as in the assay procedure. Oxidation of 125 I-iodide gives rise to the 125 I-iodination which in a mildly alkaline PH (7.5) reacts with the phenolic benzene ring of tyrosine and tyrosyl residues by a process of electrophilic attack

Differential Genetic Associations for Systemic Lupus Erythematosus Based on Anti–dsDNA Autoantibody Production

Science.gov (United States)

Chung, Sharon A.; Taylor, Kimberly E.; Graham, Robert R.; Nititham, Joanne; Lee, Annette T.; Ortmann, Ward A.; Jacob, Chaim O.; Alarcón-Riquelme, Marta E.; Tsao, Betty P.; Harley, John B.; Gaffney, Patrick M.; Moser, Kathy L.; Petri, Michelle; Demirci, F. Yesim; Kamboh, M. Ilyas; Manzi, Susan; Gregersen, Peter K.; Langefeld, Carl D.; Behrens, Timothy W.; Criswell, Lindsey A.

2011-01-01

Systemic lupus erythematosus (SLE) is a clinically heterogeneous, systemic autoimmune disease characterized by autoantibody formation. Previously published genome-wide association studies (GWAS) have investigated SLE as a single phenotype. Therefore, we conducted a GWAS to identify genetic factors associated with anti–dsDNA autoantibody production, a SLE–related autoantibody with diagnostic and clinical importance. Using two independent datasets, over 400,000 single nucleotide polymorphisms (SNPs) were studied in a total of 1,717 SLE cases and 4,813 healthy controls. Anti–dsDNA autoantibody positive (anti–dsDNA +, n = 811) and anti–dsDNA autoantibody negative (anti–dsDNA –, n = 906) SLE cases were compared to healthy controls and to each other to identify SNPs associated specifically with these SLE subtypes. SNPs in the previously identified SLE susceptibility loci STAT4, IRF5, ITGAM, and the major histocompatibility complex were strongly associated with anti–dsDNA + SLE. Far fewer and weaker associations were observed for anti–dsDNA – SLE. For example, rs7574865 in STAT4 had an OR for anti–dsDNA + SLE of 1.77 (95% CI 1.57–1.99, p = 2.0E-20) compared to an OR for anti–dsDNA – SLE of 1.26 (95% CI 1.12–1.41, p = 2.4E-04), with pheterogeneity<0.0005. SNPs in the SLE susceptibility loci BANK1, KIAA1542, and UBE2L3 showed evidence of association with anti–dsDNA + SLE and were not associated with anti–dsDNA – SLE. In conclusion, we identified differential genetic associations with SLE based on anti–dsDNA autoantibody production. Many previously identified SLE susceptibility loci may confer disease risk through their role in autoantibody production and be more accurately described as autoantibody propensity loci. Lack of strong SNP associations may suggest that other types of genetic variation or non-genetic factors such as environmental exposures have a greater impact on susceptibility to anti–dsDNA – SLE. PMID

Differential genetic associations for systemic lupus erythematosus based on anti-dsDNA autoantibody production.

Directory of Open Access Journals (Sweden)

Sharon A Chung

2011-03-01

Full Text Available Systemic lupus erythematosus (SLE is a clinically heterogeneous, systemic autoimmune disease characterized by autoantibody formation. Previously published genome-wide association studies (GWAS have investigated SLE as a single phenotype. Therefore, we conducted a GWAS to identify genetic factors associated with anti-dsDNA autoantibody production, a SLE-related autoantibody with diagnostic and clinical importance. Using two independent datasets, over 400,000 single nucleotide polymorphisms (SNPs were studied in a total of 1,717 SLE cases and 4,813 healthy controls. Anti-dsDNA autoantibody positive (anti-dsDNA +, n = 811 and anti-dsDNA autoantibody negative (anti-dsDNA -, n = 906 SLE cases were compared to healthy controls and to each other to identify SNPs associated specifically with these SLE subtypes. SNPs in the previously identified SLE susceptibility loci STAT4, IRF5, ITGAM, and the major histocompatibility complex were strongly associated with anti-dsDNA + SLE. Far fewer and weaker associations were observed for anti-dsDNA - SLE. For example, rs7574865 in STAT4 had an OR for anti-dsDNA + SLE of 1.77 (95% CI 1.57-1.99, p = 2.0E-20 compared to an OR for anti-dsDNA - SLE of 1.26 (95% CI 1.12-1.41, p = 2.4E-04, with p(heterogeneity<0.0005. SNPs in the SLE susceptibility loci BANK1, KIAA1542, and UBE2L3 showed evidence of association with anti-dsDNA + SLE and were not associated with anti-dsDNA - SLE. In conclusion, we identified differential genetic associations with SLE based on anti-dsDNA autoantibody production. Many previously identified SLE susceptibility loci may confer disease risk through their role in autoantibody production and be more accurately described as autoantibody propensity loci. Lack of strong SNP associations may suggest that other types of genetic variation or non-genetic factors such as environmental exposures have a greater impact on susceptibility to anti-dsDNA - SLE.

Absence of anti-HMG-CoA reductase autoantibodies in severe self-limited statin-related myopathy.

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Floyd, James S; Brody, Jennifer A; Tiniakou, Eleni; Psaty, Bruce M; Mammen, Andrew

2016-06-01

Patients with self-limited statin-related myopathy improve spontaneously when statins are stopped. In contrast, patients with statin-associated autoimmune myopathy have autoantibodies recognizing 3-hydroxy-3-methyl-glutaryl-coenzyme A reductase (HMGCR) and usually require immunosuppressive therapy to control their disease. On initial presentation, it can sometimes be difficult to distinguish between these 2 diseases, as both present with muscle pain, weakness, and elevated serum creatine kinase (CK) levels. The goal of this study was to determine whether patients with severe self-limited statin-related myopathy also make anti-HMGCR autoantibodies. We screened 101 subjects with severe self-limited cerivastatin-related myopathy for anti-HMGCR autoantibodies. No patient with severe self-limited cerivastatin-related myopathy had anti-HMGCR autoantibodies. Anti-HMGCR autoantibody testing can be used to help differentiate whether a patient has self-limited myopathy due to cerivastatin or autoimmune statin-associated myopathy; these findings may apply to other statins as well. Muscle Nerve 54: 142-144, 2016. © 2016 Wiley Periodicals, Inc.

Stress-induced rise in serum anti-brain autoantibody levels in the rat.

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Andrejević, S; Bukilica, M; Dimitrijević, M; Laban, O; Radulovic, J; Kovacevic-Jovanovic, V; Stanojevic, S; Vasiljevic, T; Marković, B M

1997-02-01

Sera from Wistar rats subjected to different stress procedures were tested by ELISA for the presence of autoantibodies with specificity for neuron-specific enolase (NSE) and S100 protein that are preferentially localized in neurons and glia, respectively. Autoantibodies were present in sera of animals before exposure to stress, and raised with age. Anti-NSE and anti-S100 autoantibody levels were increased one day after termination of restraint (2 hours daily, 10 days) and electric tail shock (80 shocks daily, 19 days), and in fifth and tenth week of overcrowding stress. Differences between stressed and control animals were not present one month following restraint and electric tail shock and in twentieth week of overcrowding.

Proteins oxidation and autoantibodies' reactivity against hydrogen peroxide and malondialdehyde -oxidized thyroid antigens in patients' plasmas with Graves' disease and Hashimoto Thyroiditis.

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Mseddi, Malek; Ben Mansour, Riadh; Gargouri, Bochra; Mnif, Fatma; El Ghawi, Samir; Hammami, Boutheina; Ghorbel, Abdelmonem; Abid, Mohamed; Lassoued, Saloua

2017-06-25

The aim of this study was to evaluate proteins oxidation in plasmas of two autoimmune thyroid diseases (AITD): Graves' disease (GD) and Hashimoto Thyroiditis (HT), and to determine whether oxidative modification of thyroid antigens (T.Ag) enhanced the reactivity of autoantibodies in plasmas of AITD patients compared with the reactivity towards native T.Ag. Carbonyl and thiol groups and MDA-protein adducts were assessed spectrophotometric methods in plasmas of 74 AITD patients and 65 healthy controls. The reactivities immunoglobulin (Ig)G autoantibodies towards malondialdéhyde (MDA)-modified T.Ag, hydrogen peroxide (H 2 O 2 )-modified T.Ag, native T.Ag and native derm were checked by enzyme-linked immunosorbent assay (ELISA). Evaluation of oxidized proteins exhibited high levels of MDA bound to proteins and carbonyl groups, as well as reduced thiol level in plasmas of AITD patients by comparison to healthy controls (p thyroid stimulating hormone level in HT patients in the other (r = 0.65, p < 0.001). The data suggest that high production of H 2 O 2 probably occurred during hormone synthesis could contribute to protein oxidation in AITD and to create neoepitopes responsible for autoantibody reactivity's to H 2 O 2 -oxidized T.Ag enhancement. These results provide support to the involvement of oxidative stress in AITD development and/or exacerbation. Copyright © 2017 Elsevier B.V. All rights reserved.

Autoantibodies against GPIHBP1 as a Cause of Hypertriglyceridemia

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Beigneux, Anne P; Miyashita, Kazuya; Ploug, Michael

2017-01-01

lipoprotein lipase from reaching the capillary lumen. Patients with GPIHBP1 deficiency have low plasma levels of lipoprotein lipase, impaired intravascular hydrolysis of triglycerides, and severe hypertriglyceridemia (chylomicronemia). During the characterization of a monoclonal antibody-based immunoassay......-rich lipoproteins and causing severe hypertriglyceridemia. (Funded by the National Heart, Lung, and Blood Institute and the Leducq Foundation.)........ Three of the six patients had systemic lupus erythematosus. One of these patients who had GPIHBP1 autoantibodies delivered a baby with plasma containing maternal GPIHBP1 autoantibodies; the infant had severe but transient chylomicronemia. Two of the patients with chylomicronemia and GPIHBP1...

Double Antibody Method for Immunoassay of Insulin. Its Application in Population Studies

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Welborn, T. A.; Stenhouse, N. S.; Curnow, D. H.; Johnstone, Clare J. [Department of Medicine, Raine Foundation Medical Statistics Unit and Department of Pathology, University of Western Australia, Perth (Australia)

1970-02-15

The performance of a double-antibody Immunoassay technique over a period of two years is described, during which 3300 samples from population studies were analysed for insulin concentration. The method requires safeguards to ensure that complete separation of ''free'' from ''antibody-bound'' hormone is achieved, thus labelled gamma-globulin is used in the precise preliminary standardization of precipitating antibody. The dose-response curves for crystalline insulin standards over a range of concentration 0.2 to 16,0 ng (5 to 400 micro-International-Units)/ml are consistently nonlinear, but a close fit is obtained by a cubic function obtained empirically from multiple regression analysis, which also corrects satisfactorily for ''within-assay drift'' when large numbers of samples are involved. The coefficient of variation for pooled serum standards repetitively assayed ranged from 10 to 14%. Sources of ''between-assay variability'' of the serum standards include variable integrity of the labelled insulin and the slope of the standard curve. For quality control material, the need for standards of serum as well as crystalline insulin is stressed, Serum-insulin was measured in 3300 adults of the population of Busselton, approximately 1 h after a 50 g oral glucose load. The concentrations were distributed log-normally. Females had significantly higher 'one-hour' serum-insulin levels than males, and both sexes showed a moderate rise of values with age. Multiple regression analyses revealed that the major determinant of serum-insulin was the blood-sugar level, the independent relationship being such that at ''one-hour'' blood-sugar levels exceeding 160 - 180 mg/100 ml, a decline of insulin values occurred. Body-weight had a strong positive association, and height a negative relationship, with the ''one-hour'' serum-insulin. Males with coronary heart disease and hypertension showed elevated insulin levels under 60 years of age, whereas ''ideal'' males (with obesity

Anti-signal recognition particle autoantibody ELISA validation and clinical associations.

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Aggarwal, Rohit; Oddis, Chester V; Goudeau, Danielle; Fertig, Noreen; Metes, Ilinca; Stephens, Chad; Qi, Zengbiao; Koontz, Diane; Levesque, Marc C

2015-07-01

The aim of this study was to develop and validate a quantitative anti-signal recognition particle (SRP) autoantibody serum ELISA in patients with myositis and longitudinal association with myositis disease activity. We developed a serum ELISA using recombinant purified full-length human SRP coated on ELISA plates and a secondary antibody that bound human IgG to detect anti-SRP binding. Protein immunoprecipitation was used as the gold standard for the presence of anti-SRP. Serum samples from three groups were analysed: SRP(+) myositis subjects by immunoprecipitation, SRP(-) myositis subjects by immunoprecipitation and non-myositis controls. The ELISA's sensitivity, specificity, positive predictive value and negative predictive value were evaluated. Percentage agreement and test-retest reliability were assessed. Serial samples from seven SRP immunoprecipitation-positive subjects were also tested, along with serum muscle enzymes and manual muscle testing. Using immunoprecipitation, we identified 26 SRP(+) myositis patients and 77 SRP(-) controls (including 38 patients with necrotizing myopathy). Non-myositis control patients included SLE (n = 4) and SSc (n = 7) patients. Anti-SRP positivity by ELISA showed strong agreement (97.1%) with immunoprecipitation (κ = 0.94). The sensitivity, specificity, positive predictive value, and negative predictive value of the anti-SRP ELISA were 88, 100, 100 and 96, respectively. The area under the curve was 0.94, and test-retest reliability was strong (r = 0.91, P < 0.001). Serial samples showed that anti-SRP levels paralleled changes in muscle enzymes and manual muscle testing. We developed a quantitative ELISA for detecting serum anti-SRP autoantibodies and validated the assay in myositis. Longitudinal assessment of SRP levels by ELISA may be a useful biomarker for disease activity. © The Author 2014. Published by Oxford University Press on behalf of the British Society for Rheumatology. All rights reserved. For Permissions

Antineuronal Autoantibodies : Molecular Characterization and Clinical Implication

NARCIS (Netherlands)

Hameete, M.H.|info:eu-repo/dai/nl/371750539

2017-01-01

Neurological autoimmune disorders associated with antineuronal autoantibodies result from an immune reaction directed at neuronal self-antigens. When affecting the central nervous system these can be divided into two subgroups: ‘classical’ paraneoplastic neurological syndromes (PNS) and autoimmune

Myositis-specific and myositis-associated autoantibodies in Indian patients with inflammatory myositis.

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Srivastava, Puja; Dwivedi, Sanjay; Misra, Ramnath

2016-07-01

We aimed to study the prevalence and clinical associations of myositis-specific autoantibodies (MSAs) and myositis-associated autoantibodies (MAAs) in a large cohort of Indian patients with idiopathic inflammatory myositis (IIM). Clinical details and serum samples were collected from patients with IIM (satisfying Bohan and Peter Criteria, 1975) and CTD-associated myositis. Sera were analysed for antibodies against SRP, Mi2, Jo1, PL7, PL12, EJ, OJ, Ro52, Ku, Pm-Scl 75 and PM-Scl 100, using immunoblot assay. The cohort comprised 124 patients with IIM (M:F = 1:3.6). Fifty-five of them had dermatomyositis (DM), 22 had juvenile dermatomyositis (JDM), 25 had polymyositis (PM) and 22 had connective tissue disease-associated myositis (CTD myositis). Mean disease duration was 10.9 months. ANA was positive in 84 (68.9 %), and MSAs in 61 (49.2 %) patients. Among MSAs, autoantibodies to Mi2, synthetase (Jo1, PL7, PL12, EJ) and SRP were present in 26 (20.9 %), 29 (23.4 %) and 6 (4.8 %) patients, respectively. Prevalence of MAAs was as follows: antibodies to Ro52 in 45 (36.3 %), Ku and PM-Scl 75 in 13 (10.5 %) and PM-Scl 100 in 5 (4 %) patients. Anti-Mi2 antibodies were positively associated with DM (21/55, 38.2 %; p < 0.0001) and pharyngeal weakness (13/34, 38.2 %; p = 0.004) and negatively associated with ILD (0/28; p = 0.001). ILD and mechanics' hands were significantly more in patients with anti-synthetase antibodies (16/28, 57 % and 14/22, 63.6 %; p < 0.0001). Four of six patients with anti-SRP antibody showed poor response to multiple drugs. Higher prevalence of anti-Mi2 is probably related to higher proportion of patients with DM. Absence of ILD in patients with anti-Mi2 antibody suggests that it may protect against ILD. In Indian population also, anti-synthetase antibodies are associated with ILD, and anti-SRP antibodies with poor response to treatment.

Frequency of autoimmune disorders and autoantibodies in patients with neuromyelitis optica.

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Pereira, Wildéa Lice de Carvalho Jennings; Reiche, Edna Maria Vissoci; Kallaur, Ana Paula; Oliveira, Sayonara Rangel; Simão, Andréa Name Colado; Lozovoy, Marcell Alysson Batisti; Schiavão, Lucas José Vaz; Rodrigues, Paula Raquel do Vale Pascoal; Alfieri, Daniela Frizon; Flauzino, Tamires; Kaimen-Maciel, Damacio Ramón

2017-06-01

The aim of this study was to report the frequency of autoimmune disorders and autoantibodies in 22 patients with neuromyelitis optica (NMO), as well as whether the seropositivity for autoantibodies differs between anti-aquaporin 4 (AQP4) positive and AQP4 negative NMO patients. Demographic, medical records, and a profile of autoantibodies were evaluated in 22 NMO patients, including AQP4, anti-thyroid-stimulating hormone receptor, antinuclear antibodies (ANA), anti-thyroperoxidase (anti-TPO), anti-thyroglobulin (anti-Tg), anti-double-stranded DNA, anti-neutrophil cytoplasmic, anti-cyclic citrullinate peptide, rheumatoid factor, anti-SSA/Ro, anti-SSB/La, anti-Smith antibodies (anti-Sm), anti-ribonucleoprotein, anti-nucleosome, and anti-Scl70. Thyroid-stimulating hormone and free thyroxin were measured. The frequency of women was higher than men (95.5% vs. 4.5%) and 68.2% were Afro-Brazilians. Six (27.3%) patients presented other autoimmune disorders, such as Hashimoto thyroiditis (n=2), Graves' disease (n=1), juvenile idiopathic arthritis (n=1), systemic lupus erythematosus and systemic sclerosis (n=1), and Raynaud's phenomenon (n=1). The most frequent autoantibodies were anti-AQP4 (54.5%), anti-nucleosome (31.8%), ANA (27.3%), anti-TPO (22.7%), and anti-Tg (22.7%). Difference was not observed in the frequency of autoimmune disorders when the patients were compared according to their anti-AQP4 status. The results of the present study underscored that the NMO patients present high frequency of autoantibodies against cellular antigens and the presence of autoimmune disorders. Further studies with large number of NMO patients may contribute to advances in the understanding of NMO disease mechanisms.

Thyroid Autoantibodies Display both “Original Antigenic Sin” and Epitope Spreading

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Sandra M. McLachlan

2017-12-01

Full Text Available Evidence for original antigenic sin in spontaneous thyroid autoimmunity is revealed by autoantibody interactions with immunodominant regions on thyroid autoantigens, thyroglobulin (Tg, thyroid peroxidase (TPO, and the thyrotropin receptor (TSHR A-subunit. In contrast, antibodies induced by immunization of rabbits or mice recognize diverse epitopes. Recognition of immunodominant regions persists despite fluctuations in autoantibody levels following treatment or over time. The enhancement of spontaneously arising pathogenic TSHR antibodies in transgenic human thyrotropin receptor/NOD.H2h4 mice by injecting a non-pathogenic form of TSHR A-subunit protein also provides evidence for original antigenic sin. From other studies, antigen presentation by B cells, not dendritic cells, is likely responsible for original antigenic sin. Recognition of restricted epitopes on the large glycosylated thyroid autoantigens (60-kDa A-subunit, 100-kDa TPO, and 600-kDa Tg facilitates exploring the amino acid locations in the immunodominant regions. Epitope spreading has also been revealed by autoantibodies in thyroid autoimmunity. In humans, and in mice that spontaneously develop autoimmunity to all three thyroid autoantigens, autoantibodies develop first to Tg and later to TPO and the TSHR A-subunit. The pattern of intermolecular epitope spreading is related in part to the thyroidal content of Tg, TPO and TSHR A-subunit and to the molecular sizes of these proteins. Importantly, the epitope spreading pattern provides a rationale for future antigen-specific manipulation to block the development of all thyroid autoantibodies by inducing tolerance to Tg, first in the autoantigen cascade. Because of its abundance, Tg may be the autoantigen of choice to explore antigen-specific treatment, preventing the development of pathogenic TSHR antibodies.

Autoantibodies Affect Brain Density Reduction in Nonneuropsychiatric Systemic Lupus Erythematosus Patients

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Jian Xu

2015-01-01

Full Text Available This study explores the relationship between autoantibodies and brain density reduction in SLE patients without major neuropsychiatric manifestation (NPSLE. Ninety-five NPSLE patients without obvious cerebral deficits, as determined by conventional MRI, as well as 89 control subjects, underwent high-resolution structural MRI. Whole-brain density of grey matter (GMD and white matter (WMD were calculated for each individual, and correlations between the brain density, symptom severity, immunosuppressive agent (ISA, and autoantibody levels were assessed. The GMD and WMD of the SLE group decreased compared to controls. GMD was negatively associated with SLE activity. The WMD of patients who received ISA treatment were higher than that in the patients who did not. The WMD of patients with anticardiolipin (ACL or anti-SSB/La antibodies was lower than in patients without these antibodies, while the GMD was lower in patients with anti-SM or anti-U1RNP antibodies. Thus, obvious brain atrophy can occur very early even before the development of significant symptoms and specific autoantibodies might contribute to the reduction of GMD or WMD in NPSLE patients. However, ISAs showed protective effects in minimizing GMD and WMD reduction. The presence of these specific autoantibodies might help identify early brain damage in NPSLE patients.

The Emerging Importance of Non-HLA Autoantibodies in Kidney Transplant Complications

OpenAIRE

Cardinal, Héloise; Dieudé, Mélanie; Hébert, Marie-Josée

2016-01-01

Antibodies that are specific to organ donor HLA have been involved in the majority of cases of antibody-mediated rejection in solid organ transplant recipients. However, recent data show that production of non-HLA autoantibodies can occur before transplant in the form of natural autoantibodies. In contrast to HLAs, which are constitutively expressed on the cell surface of the allograft endothelium, autoantigens are usually cryptic. Tissue damage associated with ischemia-reperfusion, vascular ...

Liver-derived systemic factors drive β-cell hyperplasia in insulin resistant states

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El Ouaamari, Abdelfattah; Kawamori, Dan; Dirice, Ercument; Liew, Chong Wee; Shadrach, Jennifer L.; Hu, Jiang; Katsuta, Hitoshi; Hollister-Lock, Jennifer; Qian, Weijun; Wagers, Amy J.; Kulkarni, Rohit N.

2013-02-21

Integrative organ cross-talk regulates key aspects of energy homeostasis and its dysregulation may underlie metabolic disorders such as obesity and diabetes. To test the hypothesis that cross-talk between the liver and pancreatic islets modulates β-cell growth in response to insulin resistance, we used the Liver-specific Insulin Receptor Knockout (LIRKO) mouse, a unique model that exhibits dramatic islet hyperplasia. Using complementary in vivo parabiosis and transplantation assays, and in vitro islet culture approaches, we demonstrate that humoral, non-neural, non-cell autonomous factor(s) induce β-cell proliferation in LIRKO mice. Furthermore, we report that a hepatocyte-derived factor(s) stimulates mouse and human β-cell proliferation in ex vivo assays, independent of ambient glucose and insulin levels. These data implicate the liver as a critical source of β-cell growth factors in insulin resistant states.

Gestational diabetes mellitus is associated with TCF7L2 gene polymorphisms independent of HLA-DQB1*0602 genotypes and islet cell autoantibodies

Science.gov (United States)

Papadopoulou, A.; Lynch, K. F.; Shaat, N.; Håkansson, R.; Ivarsson, S. A.; Berntorp, K.; Agardh, C. D.; Lernmark, Å

2011-01-01

Aims To test whether the TCF7L2 gene was associated with gestational diabetes, whether the association between TCF7L2 and gestational diabetes was independent of HLA-DQB1*0602 and islet cell autoantibodies, as well as maternal age, number of pregnancies, family history of diabetes and the HLA-DQB1 genotypes, and to test whether the distribution of HLA-DQB1 alleles was affected by country of birth. Methods We genotyped the rs7903146, rs12255372 and rs7901695 single nucleotide polymorphisms of the TCF7L2 gene in 826 mothers with gestational diabetes and in 1185 healthy control subjects in the Diabetes Prediction in Skåne Study. The mothers were also typed for HLA-DQB1 genotypes and tested for islet cell autoantibodies against GAD65, insulinoma-associated antigen-2 and insulin. Results The heterozygous genotypes CT, GT and TC of the rs7903146 (T is risk for Type 2 diabetes), rs12255372 (T is risk for Type 2 diabetes) and rs7901695 (C is risk for Type 2 diabetes), respectively, as well as the homozygous genotypes TT, TT and CC of the rs7903146, rs12255372 and rs7901695, respectively, were strongly associated with gestational diabetes (P gestational diabetes in mothers born in Sweden (P = 0.010). Conclusions The TCF7L2 was associated with susceptibility for gestational diabetes independently of the presence of HLA-DQB1*0602 and islet cell autoantibodies and other factors such as maternal age, number of pregnancies, family history of diabetes and other HLA-DQ genotypes. The HLA-DQB1*0602 was negatively associated with gestational diabetes in mothers born in Sweden. PMID:21672010

Rituximab selectively suppresses specific islet antibodies.

Science.gov (United States)

Yu, Liping; Herold, Kevan; Krause-Steinrauf, Heidi; McGee, Paula L; Bundy, Brian; Pugliese, Alberto; Krischer, Jeff; Eisenbarth, George S

2011-10-01

The TrialNet Study Group evaluated rituximab, a B-cell-depleting monoclonal antibody, for its effect in new-onset patients with type 1A diabetes. Rituximab decreased the loss of C-peptide over the first year of follow-up and markedly depleted B lymphocytes for 6 months after administration. This article analyzes the specific effect of rituximab on multiple islet autoantibodies. A total of 87 patients between the ages of 8 and 40 years received either rituximab or a placebo infusion weekly for four doses close to the onset of diabetes. Autoantibodies to insulin (IAAs), GAD65 (GADAs), insulinoma-associated protein 2 (IA2As), and ZnT8 (ZnT8As) were measured with radioimmunoassays. The primary outcome for this autoantibody analysis was the mean level of autoantibodies during follow-up. Rituximab markedly suppressed IAAs compared with the placebo injection but had a much smaller effect on GADAs, IA2As, and ZnT8As. A total of 40% (19 of 48) of rituximab-treated patients who were IAA positive became IAA negative versus 0 of 29 placebo-treated patients (P 1 year in insulin-treated patients. For the patients receiving insulin for >2 weeks prior to rituximab administration, we cannot assess whether rituximab not only blocks the acquisition of insulin antibodies induced by insulin administration and/or also suppresses preformed insulin autoantibodies. Studies in prediabetic non-insulin-treated patients will likely be needed to evaluate the specific effects of rituximab on levels of IAAs.

Autoantibodies persist in relatives to systemic lupus erythematosus patients during 12 years follow-up

DEFF Research Database (Denmark)

Langkilde, Henrik; Voss, A; Heegaard, N

2017-01-01

BACKGROUND: Systemic lupus erythematosus (SLE) is an autoimmune disease with presence of autoantibodies and characteristic multi-organ involvement. Relatives of SLE patients have an increased risk of autoantibody production and autoimmune diseases. METHODS: In 2001, 226 first degree relatives (FDRs...

Diagnostic performance of a commercial immunoblot assay for myositis antibody testing.

Science.gov (United States)

Bundell, Chris; Rojana-Udomsart, Arada; Mastaglia, Frank; Hollingsworth, Peter; McLean-Tooke, Andrew

2016-06-01

The objective of this study was to establish a population based reference range for a commercial immunoblot assay detecting myositis specific autoantibodies (MSAs) and myositis associated autoantibodies (MAAs), and to assess the diagnostic performance of this reference range against the manufacturer's recommended ranges in a myositis patient cohort. A total of 124 patients from a myositis cohort and 197 healthy controls were serologically assessed using a commercial immunoblot containing eleven autoantigens (Jo-1, EJ, OJ, PL7, PL12, Mi-2, SRP, Ku, PMScl75, PMScl100 and Ro52) according to the manufacturer's instructions. Use of the manufacturer's reference ranges resulted in detection of MSAs in 19.4% of myositis patients and 9.1% of controls; MAAs were detected in 41.1% of myositis patients and 14.2% of controls. Reference values derived from the healthy control population resulted in significant differences in cut-off values for some autoantibodies, particularly Ro52 and PMScl75. Use of local reference ranges reduced detection of MSAs to 16.9% of myositis patients and 3% of healthy controls, with MAAs 23.4% of patients and 2% of healthy controls. Application of population based reference ranges resulted in significant differences in detection of MSAs and MAAs compared to the manufacturer's recommended ranges. Cut-off levels should be assessed to ensure suitability for the population tested. Copyright © 2016. Published by Elsevier B.V.

MS2 VLP-based delivery of microRNA-146a inhibits autoantibody production in lupus-prone mice

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Pan Y

2012-12-01

Full Text Available Yang Pan,1,2 Tingting Jia,1,2 Yuan Zhang,1,2 Kuo Zhang,1 Rui Zhang,1 Jinming Li,1 Lunan Wang11National Center for Clinical Laboratories, Beijing Hospital of the Ministry of Health, Beijing, People’s Republic of China; 2Graduate School, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing, People’s Republic of ChinaBackground: Systemic lupus erythematosus (SLE is a chronic autoimmune disease characterized by the presence of pathogenic autoantibodies. Recent studies suggest that microRNAs (miRNAs play an essential role in immunoregulation and may be involved in the pathogenesis of SLE. Therefore, it was of interest to investigate the potential therapeutic application of miRNAs in SLE, a concept that has not been thoroughly investigated thus far. Virus-like particles (VLPs are a type of recombinant nanoparticle enveloped by certain proteins derived from the outer coat of a virus. Herein, we describe a novel miRNA-delivery approach via bacteriophage MS2 VLPs and investigate the therapeutic effects of miR-146a, a well-studied and SLE-related miRNA, in BXSB lupus-prone mice.Methods: VLPs containing miR-146a, and the control VLPs, were prepared using an Escherichia coli expression system and then administered to lupus-prone mice over a 12-day period. We performed an enzyme-linked immunosorbent assay to evaluate the anti-dsDNA antibody, autoantibody to nuclear antigen (ANA, total IgG and total IgM levels in serum. The expression of miR-146a was analyzed by qRT-PCR. SLE-related cytokines as well as some toll-like receptor signaling pathway molecules were also measured.Results: Treatment with MS2-miR146a VLP showed profound effects on lupus-prone BXSB mice, including an increased level of mature miR-146a, which led to a significant reduction in the expression of autoantibodies and total IgG. Remarkably, these mice also exhibited reduced levels of proinflammatorycytokines, including IFN-Interferon-α (IFN-α, Interleukin-1β (Il-1

Hello from the Other Side: How Autoantibodies Circumvent the Blood–Brain Barrier in Autoimmune Encephalitis

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Tyler Cutforth

2017-04-01

Full Text Available Antibodies against neuronal receptors and synaptic proteins are associated with autoimmune encephalitides (AE that produce movement and psychiatric disorders. In order to exert their pathological effects on neural circuits, autoantibodies against central nervous system (CNS targets must gain access to the brain and spinal cord by crossing the blood–brain barrier (BBB, a tightly regulated gateway formed by endothelial cells lining CNS blood vessels. To date, the pathogenic mechanisms that underlie autoantibody-triggered encephalitic syndromes are poorly understood, and how autoantibodies breach the barrier remains obscure for almost all AE syndromes. The relative importance of cellular versus humoral immune mechanisms for disease pathogenesis also remains largely unexplored. Here, we review the proposed triggers for various autoimmune encephalopathies and their animal models, as well as basic structural features of the BBB and how they differ among various CNS regions, a feature that likely underlies some regional aspects of autoimmune encephalitis pathogenesis. We then discuss the routes that antibodies and immune cells employ to enter the CNS and their implications for AE. Finally, we explore future therapeutic strategies that may either preserve or restore barrier function and thereby limit immune cell and autoantibody infiltration into the CNS. Recent mechanistic insights into CNS autoantibody entry indicate promising future directions for therapeutic intervention beyond current, short-lived therapies that eliminate circulating autoantibodies.

Hello from the Other Side: How Autoantibodies Circumvent the Blood-Brain Barrier in Autoimmune Encephalitis.

Science.gov (United States)

Platt, Maryann P; Agalliu, Dritan; Cutforth, Tyler

2017-01-01

Antibodies against neuronal receptors and synaptic proteins are associated with autoimmune encephalitides (AE) that produce movement and psychiatric disorders. In order to exert their pathological effects on neural circuits, autoantibodies against central nervous system (CNS) targets must gain access to the brain and spinal cord by crossing the blood-brain barrier (BBB), a tightly regulated gateway formed by endothelial cells lining CNS blood vessels. To date, the pathogenic mechanisms that underlie autoantibody-triggered encephalitic syndromes are poorly understood, and how autoantibodies breach the barrier remains obscure for almost all AE syndromes. The relative importance of cellular versus humoral immune mechanisms for disease pathogenesis also remains largely unexplored. Here, we review the proposed triggers for various autoimmune encephalopathies and their animal models, as well as basic structural features of the BBB and how they differ among various CNS regions, a feature that likely underlies some regional aspects of autoimmune encephalitis pathogenesis. We then discuss the routes that antibodies and immune cells employ to enter the CNS and their implications for AE. Finally, we explore future therapeutic strategies that may either preserve or restore barrier function and thereby limit immune cell and autoantibody infiltration into the CNS. Recent mechanistic insights into CNS autoantibody entry indicate promising future directions for therapeutic intervention beyond current, short-lived therapies that eliminate circulating autoantibodies.

Identification of high-affinity anti-IL-1 α autoantibodies in normal human serum as an interfering substance in a sensitive enzyme-linked immunosorbent assay for IL-1 α

International Nuclear Information System (INIS)

Mae, N.; Liberato, D.J.; Chizzonite, R.; Satoh, H.

1991-01-01

A highly reproducible, sensitive, and specific sandwich enzyme-linked immunosorbent assay (ELISA) for recombinant human IL-1 α (rhIL-1 alpha) has been developed. Results from this ELISA have demonstrated that the concentration of rhIL-1 α added to normal human serum (NHS) decreased by 16.3% after 3 h and 24.9% after 6 h at room temperature. Molecular exclusion column chromatography with Sephacryl S-300 HR revealed that 125I-labeled IL-1 α added to normal human serum rapidly formed higher molecular weight complexes without indication of proteolytic degradation. The observed reduction in immunoreactivity was correlated with this protein complex formation and accounted for the apparent instability of rhIL-1 α in NHS. Immunoblot analysis indicated that the molecular weight of the binding protein was 150-160K, and the IL-1 α binding activity was removed and recovered from NHS by Protein-G affinity chromatography; indicating that the binding protein was IL-1 α-specific IgG. The binding of 125I-labeled IL-1 α to the serum binding proteins could be inhibited by unlabeled IL-1 alpha (IC50 = 7.4 x 10(-11) M) but not by unlabeled IL-1 β. Kinetic analysis with 125I-labeled IL-1 alpha revealed that the average binding affinity of these IL-1 α-specific IgGs was 4.7 x 10(10) M-1. These results suggest that these autoantibodies may interfere with the detection of IL-1 α in human serum by various assay systems and also could be a regulator of circulating IL-1 α

Insulin and insulin-like growth factor-1 increased in preterm neonates following massage therapy.

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Field, Tiffany; Diego, Miguel; Hernandez-Reif, Maria; Dieter, John N I; Kumar, Adarsh M; Schanberg, Saul; Kuhn, Cynthia

2008-12-01

To determine if massage therapy increased serum insulin and insulin-like growth factor-1 (IGF-1) in preterm neonates. Forty-two preterm neonates who averaged 34.6 weeks (M = 29.5 wk gestational age; M birth weight = 1237 g) and were in the "grower" (step-down) nursery were randomly assigned to a massage therapy group (body stroking and passive limb movements for three, 15-minute periods per day for 5 days) or a control group that received the standard nursery care without massage therapy. On Days 1 and 5, the serum collected by clinical heelsticks was also assayed for insulin and IGF-1, and weight gain and kilocalories consumed were recorded daily. Despite similar formula intake, the massaged preterm neonates showed greater increases during the 5-day period in (1) weight gain; (2) serum levels of insulin; and (3) IGF-1. Increased weight gain was significantly correlated with insulin and IGF-1. Previous data suggested that preterm infant weight gain following massage therapy related to increased vagal activity, which suggests decreased stress and gastric motility, which may contribute to more efficient food absorption. The data from this study suggest for the first time that weight gain was also related to increased serum insulin and IGF-1 levels following massage therapy. Preterm infants who received massage therapy not only showed greater weight gain but also a greater increase in serum insulin and IGF-1 levels, suggesting that massage therapy might be prescribed for all growing neonates.

IgG4 autoantibodies are inhibitory in the autoimmune disease bullous pemphigoid.

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Zuo, Yagang; Evangelista, Flor; Culton, Donna; Guilabert, Antonio; Lin, Lin; Li, Ning; Diaz, Luis; Liu, Zhi

2016-09-01

The IgG4 subclass of antibodies exhibits unique characteristics that suggest it may function in an immunoregulatory capacity. The inhibitory function of IgG4 has been well documented in allergic disease by the demonstration of IgG4 blocking antibodies, but similar functions have not been explored in autoimmune disease. Bullous pemphigoid (BP) is a subepidermal autoimmune blistering disease characterized by autoantibodies directed against BP180 and an inflammatory infiltrate including eosinophils and neutrophils. Animal models have revealed that the NC16A region within BP180 harbors the critical epitopes necessary for autoantibody mediated disease induction. BP180 NC16A-specific IgG belong to the IgG1, IgG3, and IgG4 subclasses. The purpose of this study was to determine effector functions of different IgG subclasses of NC16A-specific autoantibodies in BP. We find that IgG4 anti-NC16A autoantibodies inhibit the binding of IgG1 and IgG3 autoantibodies to the NC16A region. Moreover, IgG4 anti-NC16A blocks IgG1 and IgG3 induced complement fixation, neutrophil infiltration, and blister formation clinically and histologically in a dose-dependent manner following passive transfer to humanized BP180-NC16A mice. These findings highlight the inhibitory role of IgG4 in autoimmune disease and have important implications for the treatment of BP as well as other antibody mediated inflammatory and autoimmune diseases. Copyright © 2016 Elsevier Ltd. All rights reserved.

Autoantibodies in Chronic Obstructive Pulmonary Disease

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Lifang Wen

2018-01-01

Full Text Available Chronic obstructive pulmonary disease (COPD, the fourth leading cause of death worldwide, is characterized by irreversible airflow limitation based on obstructive bronchiolitis, emphysema, and chronic pulmonary inflammation. Inhaled toxic gases and particles, e.g., cigarette smoke, are major etiologic factors for COPD, while the pathogenesis of the disease is only partially understood. Over the past decade, an increasing body of evidence has been accumulated for a link between COPD and autoimmunity. Studies with clinical samples have demonstrated that autoantibodies are present in sera of COPD patients and some of these antibodies correlate with specific disease phenotypes. Furthermore, evidence from animal models of COPD has shown that autoimmunity against pulmonary antigens occur during disease development and is capable of mediating COPD-like symptoms. The idea that autoimmunity could contribute to the development of COPD provides a new angle to understand the pathogenesis of the disease. In this review article, we provide an advanced overview in this field and critically discuss the role of autoantibodies in the pathogenesis of COPD.

Generation of insulin-producing human mesenchymal stem cells using recombinant adeno-associated virus.

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Kim, Jeong Hwan; Park, Si-Nae; Suh, Hwal

2007-02-28

The purpose of current experiment is the generation of insulin-producing human mesenchymal stem cells as therapeutic source for the cure of type 1 diabetes. Type 1 diabetes is generally caused by insulin deficiency accompanied by the destruction of islet beta-cells. In various trials for the treatment of type 1 diabetes, cell-based gene therapy using stem cells is considered as one of the most useful candidate for the treatment. In this experiment, human mesenchymal stem cells were transduced with AAV which is containing furin-cleavable human preproinsulin gene to generate insulin-producing cells as surrogate beta-cells for the type 1 diabetes therapy. In the rAAV production procedure, rAAV was generated by transfection of AD293 cells. Human mesenchymal stems cells were transduced using rAAV with a various multiplicity of infection. Transduction of recombinant AAV was also tested using beta-galactosidse expression. Cell viability was determined by using MTT assay to evaluate the toxicity of the transduction procedure. Expression and production of Insulin were tested using reverse transcriptase-polymerase chain reaction and immunocytochemistry. Secretion of human insulin and C-peptide from the cells was assayed using enzyme-linked immunosorbent assay. Production of insulin and C-peptide from the test group represented a higher increase compared to the control group. In this study, we examined generation of insulin-producing cells from mesenchymal stem cells by genetic engineering for diabetes therapy. This work might be valuable to the field of tissue engineering for diabetes treatment.

Efficacy of D- red blood cell transfusion and rituximab therapy in autoimmune hemolytic anemia with anti-D and panreactive autoantibodies arising after hematopoietic stem cell transplant.

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Minakawa, Keiji; Ohto, Hitoshi; Yasuda, Hiroyasu; Saito, Shunichi; Kawabata, Kinuyo; Ogawa, Kazuei; Nollet, Kenneth E; Ikeda, Kazuhiko

2018-04-17

Autoimmune hemolytic anemia (AIHA) is caused by autoantibodies to red blood cells (RBCs), which can be panreactive and/or specific to Rh/other blood group antigens. We report a severe case of AIHA after bone marrow transplantation (BMT) due to autoanti-D triggered by reactivation of Epstein-Barr virus (EBV) infection. A combined strategy of D- RBC transfusion and administration of anti-CD20 monoclonal antibody (MoAb) resolved the hemolysis. A 33-year-old male underwent allogeneic BMT from an ABO-identical and HLA-matched unrelated male donor. Five months later, while having mild chronic graft-versus-host disease, he manifested AIHA, with a hemoglobin (Hb) level of 5.1 g/dL on AIHA Day 2 (Posttransplant Day 156) and was refractory to D+ RBCs, with a Hb level of 2.4 g/dL on AIHA Day 6. Anti-D-like autoantibodies (titer 1280, subclass immunoglobulin G 1 , monocyte monolayer assay 28.7%) and panreactive (titer 40) were identified. Changing the RBC transfusion strategy to D- increased his Hb level to 6.7 g/dL on Day 10. Administration of anti-CD20 MoAb mitigated EBV-related B-cell proliferation and reduced anti-D autoantibody titer to 320 by Day 16 with normalized Hb concentration after 6 months. In severe AIHA, when standard treatment and regular RBC transfusions are ineffective, transfusion of RBCs lacking the target antigen(s) of autoantibodies and administration of anti-CD20 MoAb should be considered. © 2018 AABB.

Complete stable remission and autoantibody specificity in myasthenia gravis.

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Baggi, Fulvio; Andreetta, Francesca; Maggi, Lorenzo; Confalonieri, Paolo; Morandi, Lucia; Salerno, Franco; Bernasconi, Pia; Montomoli, Cristina; Barberis, Massimo; Mantegazza, Renato; Antozzi, Carlo

2013-01-08

Patients with myasthenia gravis (MG) are subgrouped as acetylcholine receptor (AChR)-positive, muscle-specific kinase (MuSK)-positive, and AChR/MuSK-negative MG (or double negative [DN]) on the basis of autoantibody assay. We investigated the relationships between autoantibody specificity, main clinical features, and outcome of the disease, in particular the occurrence of complete stable remission (CSR), by means of a retrospective study on a cohort of 677 Italian patients with MG. A total of 517 (76%) patients with AChR-positive MG, 55 (8%) patients with MuSK-positive MG, and 105 (16%) patients with DN MG were included in the study. Kaplan-Meier and Cox proportional hazard regression analyses were used to evaluate associations between baseline characteristics, antibody specificity, and CSR. Clinical stage at onset and at maximal worsening was more severe for MuSK-positive patients: bulbar impairment at maximal worsening was found in 83.6% of MuSK-positive patients compared with 58.6% of AChR-positive patients and 43.8% of DN patients (p CSR was observed in 3.6% of MuSK-positive patients compared with 22.2% of AChR-positive and 21.9% of DN patients. In the whole MG cohort, onset before age 40 (hazard ratio [HR] = 1.96, 95% confidence interval [CI] 1.27-3.02, p = 0.002) and ocular and generalized clinical stages at maximal worsening were associated with CSR (ocular, HR = 8.05, 95% CI 1.88-34.53, p = 0.005; generalized, HR = 3.71, 95% CI 1.16-11.90, p = 0.023; bulbar, HR = 3.16, 95% CI 1.00-10.05, p = 0.051). MuSK antibodies identify a clinically distinguishable, more severe form of MG since the disease onset, with a lower occurrence of CSR. These features should be considered by the clinician in the management of this particular form of MG.

Association between anti-thyroid peroxidase and anti-cytokeratin 18 autoantibodies and bronchial asthma in women

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Hala A. Mohammad

2016-01-01

Conclusion: Positive anti-TPO autoantibodies and anti-CK18 autoantibodies in asthmatic patients and their higher level in the non-allergic asthma group may strengthen the presence of a hidden autoimmune phenomenon in non-allergic asthma.

Diabetes classification: grey zones, sound and smoke: Action LADA 1

DEFF Research Database (Denmark)

Leslie, R D G; Kolb, H; Schloot, N C

2008-01-01

-insulin-requiring diabetes, an islet autoantibody such as glutamic acid decarboxylase autoantibodies (GADA) or cytoplasmic islet cell autoantibodies (ICA), and no need for insulin treatment for several months post-diagnosis. But while some would split diabetes into distinct subtypes, there is a strong case......Diseases gain identity from clinical phenotype as well as genetic and environmental aetiology. The definition of type 1 diabetes is clinically exclusive, comprising patients who are considered insulin dependent at diagnosis, whilst the definition of type 2 diabetes is inclusive, only excluding...... those who are initially insulin dependent. Ketosis-prone diabetes (KPD) and latent autoimmune diabetes in adults (LADA) are each exclusive forms of diabetes which are, at least initially, clinically distinct from type 2 diabetes and type 1 diabetes, and each have a different natural history from...

MCF-7 human mammary adenocarcinoma cells exhibit augmented responses to human insulin on a collagen IV surface

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Listov-Saabye, Nicolai; Jensen, Marianne Blirup; Kiehr, Benedicte

2009-01-01

Human mammary cell lines are extensively used for preclinical safety assessment of insulin analogs. However, it is essentially unknown how mitogenic responses can be optimized in mammary cell-based systems. We developed an insulin mitogenicity assay in MCF-7 human mammary adenocarcinoma cells......, under low serum (0.1% FCS) and phenol red-free conditions, with 3H thymidine incorporation as endpoint. Based on EC50 values determined from 10-fold dilution series, beta-estradiol was the most potent mitogen, followed by human IGF-1, human AspB10 insulin and native human insulin. AspB10 insulin...... was significantly more mitogenic than native insulin, validating the ability of the assay to identify hypermitogenic human insulin analogs. With MCF-7 cells on a collagen IV surface, the ranking of mitogens was maintained, but fold mitogenic responses and dynamic range and steepness of dose-response curves were...

Enzymatic amplification of a flow-injected thermometric enzyme-linked immunoassay for human insulin.

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Mecklenburg, M; Lindbladh, C; Li, H; Mosbach, K; Danielsson, B

1993-08-01

A flow-injected thermometric enzyme linked immunoassay for human insulin which employs the lactate dehydrogenase/lactate oxidase (LDH/LOD) substrate recycling system for signal amplification is described. The system is composed of two columns, an immunosorbent column containing immobilized anti-insulin antibodies for sensing and a recycling column containing immobilized LDH/LOD/Catalase for detection. The effect of flow rates, conjugate concentrations, and chromatographic support material upon the sensitivity of the assay are investigated. The assay has a detection limit of 0.025 microgram/ml and a linear range from 0.05 to 2 micrograms/ml. This corresponds to a 10-fold increase in sensitivity over the unamplified system. A recombinant human insulin-proinsulin conjugate was also tested. The results show that enzymatic amplification can be employed to increase the sensitivity and reproducibility of flow injection assay-based biosensors. The implications of these results upon on-line analysis are discussed.

An autoantibody against Nε-(carboxyethyl)lysine (CEL): Possible involvement in the removal of CEL-modified proteins by macrophages

International Nuclear Information System (INIS)

Mera, Katsumi; Nagai, Ryoji; Takeo, Kazuhiro; Izumi, Miyoko; Maruyama, Toru; Otagiri, Masaki

2011-01-01

Highlights: → A higher amount of autoantibody against CEL than that of other AGEs was observed in human plasma. → The purified human anti-CEL autoantibody specifically reacted with CEL. → Anti-CEL antibody accelerated the uptake of 125 I-CEL-HSA by macrophage in vitro. → Endocytic uptake of 125 I-CEL-HSA by mice liver was accelerated in the presence of anti-CEL antibody. -- Abstract: Advanced glycation end products (AGEs) are believed to play a significant role in the development of diabetic complications. In this study, we measured the levels of autoantibodies against several AGE structures in healthy human plasma and investigated the physiological role of the autoantibodies. A high titer of the autoantibody against N ε -(carboxyethyl)lysine (CEL) was detected in human plasma compared with other AGE structures such as CML and pentosidine. The purified human anti-CEL autoantibody reacted with CEL-modified human serum albumin (CEL-HSA), but not CML-HSA. A rabbit polyclonal anti-CEL antibody, used as a model autoantibody against CEL, accelerated the uptake of CEL-HSA by macrophages, but did not enhance the uptake of native HSA. Furthermore, when 125 I-labeled CEL-HSA was injected into the tail vein of mice, accumulation of 125 I-CEL-HSA in the liver was accelerated by co-injection of the rabbit anti-CEL antibody. These results demonstrate that the autoantibody against CEL in plasma may play a role in the macrophage uptake of CEL-modified proteins.

Studies on insulin receptor, 2

International Nuclear Information System (INIS)

Sakai, Yukio

1979-01-01

The present study is to investigate an influence of starvation and high fat diet on insulin receptor of the plasma membrane by means of radioreceptor assay using 125 I-labelled insulin. Male guinea pigs of Hartley strain were employed for the starvation study, and 125 I-insulin binding capacity on the plasma membrane of the liver and kidney was determined at 24, 48 and 72 hours of the fast after the last meal. Male rats of Wistar strain were employed for the high fat study where the diet containing 35% of butter was fed ad libitum for 38 or 68 days. The animals were killed at the fast of 12 hours, and 125 I-insulin binding capacity on the plasma membrane of the liver was determined. The results obtained are summarized as follows: 1) An increase in 125 I-insulin binding capacity on the plasma membrane of the liver and kidney was observed by the starvation for 24 to 72 hours. 2) The mechanism of the increase by starvation was considered to be different by the organs; it was due to an increase in number of insulin receptor in the liver, and due to an increase in affinity of insulin receptor in the kidney. 3) In non-obese rats fed with high fat diet, the number of insulin receptor on the liver plasma membrane showed a decrease, and this observation clearly indicated that the decrease in number of the receptor did not depend on the obesity. 4) Obese rats also fed with high fat diet presented a decrease in number of insulin receptor without an elevation of insulin levels in the circulating blood. This indicated that at least in the obese rats fed with high fat diet, the decrease in number of the receptor was not due to hyperinsulinemia. (author)

Association of Autoantibodies to BP180 with Disease Activity in Greek Patients with Bullous Pemphigoid

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Aikaterini Patsatsi

2012-01-01

Full Text Available 39 bullous pemphigoid (BP patients were studied to assess the clinical significance of anti-BP180 and anti-BP230 circulating autoantibodies of BP and correlate their titers with the clinical scores of the BP Disease Area Index (BPDAI and the Autoimmune Bullous Skin Disorder Intensity Score (ABSIS as well as with the intensity of pruritus measured by the BPDAI pruritus component. All parameters were evaluated by the time of diagnosis (baseline, month 3, and month 6. Titers of anti-BP180 autoantibodies were strongly correlated with BPDAI (, and ABSIS (, values, as well as with BPDAI component for the intensity of pruritus (, at baseline. At month 3, titers of anti-BP180 autoantibodies were strongly correlated with BPDAI (, and ABSIS (, values, as well as with the BPDAI component for the intensity of pruritus (, . At month 6, titers of anti-BP180 autoantibodies were strongly correlated with BPDAI (, and ABSIS (, values, as well as with the BPDAI component for the intensity of pruritus (, . There was no statistically significant correlation between titers of anti-BP230 autoantibodies and the BPDAI, ABSIS, and BPDAI component for the intensity of pruritus at the same time points.

Multiple Autoantibodies Display Association with Lymphopenia, Proteinuria, and Cellular Casts in a Large, Ethnically Diverse SLE Patient Cohort

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Rufei Lu

2012-01-01

Full Text Available Purpose. This study evaluates high-throughput autoantibody screening and determines associated systemic lupus erythematosus (SLE clinical features in a large lupus cohort. Methods. Clinical and demographic information, along with serum samples, were obtained from each SLE study participant after appropriate informed consent. Serum samples were screened for 10 distinct SLE autoantibody specificities and examined for association with SLE ACR criteria and subcriteria using conditional logistic regression analysis. Results. In European-American SLE patients, autoantibodies against 52 kD Ro and RNP 68 are independently enriched in patients with lymphopenia, anti-La, and anti-ribosomal P are increased in patients with malar rash, and anti-dsDNA and anti-Sm are enriched in patients with proteinuria. In African-American SLE patients, cellular casts associate with autoantibodies against dsDNA, Sm, and Sm/nRNP. Conclusion. Using a high-throughput, bead-based method of autoantibody detection, anti-dsDNA is significantly enriched in patienets with SLE ACR renal criteria as has been previously described. However, lymphopenia is associated with several distinct autoantibody specificities. These findings offer meaningful information to allow clinicians and clinical investigators to understand which autoantibodies correlate with select SLE clinical manifestations across common racial groups using this novel methodology which is expanding in clinical use.

Muscle autoantibodies in myasthenia gravis: beyond diagnosis?

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Meriggioli, Matthew N; Sanders, Donald B

2012-01-01

Myasthenia gravis is an autoimmune disorder of the neuromuscular junction. A number of molecules, including ion channels and other proteins at the neuromuscular junction, may be targeted by autoantibodies leading to abnormal neuromuscular transmission. In approximately 85% of patients, autoantibodies, directed against the postsynaptic nicotinic acetylcholine receptor can be detected in the serum and confirm the diagnosis, but in general, do not precisely predict the degree of weakness or response to therapy. Antibodies to the muscle-specific tyrosine kinase are detected in approximately 50% of generalized myasthenia gravis patients who are seronegative for anti-acetylcholine receptor antibodies, and levels of anti-muscle-specific tyrosine kinase antibodies do appear to correlate with disease severity and treatment response. Antibodies to other muscle antigens may be found in the subsets of myasthenia gravis patients, potentially providing clinically useful diagnostic information, but their utility as relevant biomarkers (measures of disease state or response to treatment) is currently unclear. PMID:22882218

Genome-wide association analysis of autoantibody positivity in type 1 diabetes cases.

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Vincent Plagnol

2011-08-01

Full Text Available The genetic basis of autoantibody production is largely unknown outside of associations located in the major histocompatibility complex (MHC human leukocyte antigen (HLA region. The aim of this study is the discovery of new genetic associations with autoantibody positivity using genome-wide association scan single nucleotide polymorphism (SNP data in type 1 diabetes (T1D patients with autoantibody measurements. We measured two anti-islet autoantibodies, glutamate decarboxylase (GADA, n = 2,506, insulinoma-associated antigen 2 (IA-2A, n = 2,498, antibodies to the autoimmune thyroid (Graves' disease (AITD autoantigen thyroid peroxidase (TPOA, n = 8,300, and antibodies against gastric parietal cells (PCA, n = 4,328 that are associated with autoimmune gastritis. Two loci passed a stringent genome-wide significance level (p<10(-10: 1q23/FCRL3 with IA-2A and 9q34/ABO with PCA. Eleven of 52 non-MHC T1D loci showed evidence of association with at least one autoantibody at a false discovery rate of 16%: 16p11/IL27-IA-2A, 2q24/IFIH1-IA-2A and PCA, 2q32/STAT4-TPOA, 10p15/IL2RA-GADA, 6q15/BACH2-TPOA, 21q22/UBASH3A-TPOA, 1p13/PTPN22-TPOA, 2q33/CTLA4-TPOA, 4q27/IL2/TPOA, 15q14/RASGRP1/TPOA, and 12q24/SH2B3-GADA and TPOA. Analysis of the TPOA-associated loci in 2,477 cases with Graves' disease identified two new AITD loci (BACH2 and UBASH3A.

Sulfonylureas and Glinides as New PPARγ Agonists:. Virtual Screening and Biological Assays

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Scarsi, Marco; Podvinec, Michael; Roth, Adrian; Hug, Hubert; Kersten, Sander; Albrecht, Hugo; Schwede, Torsten; Meyer, Urs A.; Rücker, Christoph

2007-12-01

This work combines the predictive power of computational drug discovery with experimental validation by means of biological assays. In this way, a new mode of action for type 2 diabetes drugs has been unvealed. Most drugs currently employed in the treatment of type 2 diabetes either target the sulfonylurea receptor stimulating insulin release (sulfonylureas, glinides), or target PPARγ improving insulin resistance (thiazolidinediones). Our work shows that sulfonylureas and glinides bind to PPARγ and exhibit PPARγ agonistic activity. This result was predicted in silico by virtual screening and confirmed in vitro by three biological assays. This dual mode of action of sulfonylureas and glinides may open new perspectives for the molecular pharmacology of antidiabetic drugs, since it provides evidence that drugs can be designed which target both the sulfonylurea receptor and PPARγ. Targeting both receptors could in principle allow to increase pancreatic insulin secretion, as well as to improve insulin resistance.

First experiences with the AMERLEX-MAB FREE T4 assay

International Nuclear Information System (INIS)

Nijhof, W.A.; Penders, T.J.

1989-01-01

The new Amerlex-MAB FT 4 is a quick direct free T 4 assay with good reproducability. The correlation between the Amerlex-MAB FT 4 and the free T 4 of Byk is good. In the non-thyreoidal illness patient group no deviation for the values were found. Amerlex-MAB FT 4 is cheaper, because no total T4 has to be measured. More research has to be done for special patient sera. Disturbing influences as free fatty acids, heparin and auto-antibodies have to be checked. (R.B.). 3 refs.; 3 figs.; 4 tabs

Detection of autoantibodies against reactive oxygen species modified glutamic acid decarboxylase-65 in type 1 diabetes associated complications

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Mashal Subhash N

2011-03-01

Full Text Available Abstract Background Autoantibodies against glutamate decarboxylase-65 (GAD65Abs are thought to be a major immunological tool involved in pathogenic autoimmunity development in various diseases. GAD65Abs are a sensitive and specific marker for type 1 diabetes (T1D. These autoantibodies can also be found in 6-10% of patients classified with type 2 diabetes (T2D, as well as in 1-2% of the healthy population. The latter individuals are at low risk of developing T1D because the prevalence rate of GAD65Abs is only about 0.3%. It has, therefore, been suggested that the antibody binding to GAD65 in these three different GAD65Ab-positive phenotypes differ with respect to epitope specificity. The specificity of reactive oxygen species modified GAD65 (ROS-GAD65 is already well established in the T1D. However, its association in secondary complications of T1D has not yet been ascertained. Hence this study focuses on identification of autoantibodies against ROS-GAD65 (ROS-GAD65Abs and quantitative assays in T1D associated complications. Results From the cohort of samples, serum autoantibodies from T1D retinopathic and nephropathic patients showed high recognition of ROS-GAD65 as compared to native GAD65 (N-GAD65. Uncomplicated T1D subjects also exhibited reactivity towards ROS-GAD65. However, this was found to be less as compared to the binding recorded from complicated subjects. These results were further proven by competitive ELISA estimations. The apparent association constants (AAC indicate greater affinity of IgG from retinopathic T1D patients (1.90 × 10-6 M followed by nephropathic (1.81 × 10-6 M and uncomplicated (3.11 × 10-7 M T1D patients for ROS-GAD65 compared to N-GAD65. Conclusion Increased oxidative stress and blood glucose levels with extended duration of disease in complicated T1D could be responsible for the gradual formation and/or exposing cryptic epitopes on GAD65 that induce increased production of ROS-GAD65Abs. Hence regulation of ROS

Prevalence of serum anti-neuronal autoantibodies in patients admitted to acute psychiatric care

DEFF Research Database (Denmark)

Schou, M; Sæther, S G; Borowski, K

2016-01-01

BACKGROUND: Autoimmune encephalitis associated with anti-neuronal antibodies may be challenging to distinguish from primary psychiatric disorders. The significance of anti-neuronal antibodies in psychiatric patients without clear evidence of autoimmune encephalitis is unknown. We investigated...... the serum prevalence of six anti-neuronal autoantibodies in a cohort of unselected patients admitted to acute psychiatric care. METHOD: Serum was drawn from 925 patients admitted to acute psychiatric in-patient care. Psychiatric diagnoses were set according to International Classification of Diseases (ICD......)-10 criteria. Antibody analysis was performed with an indirect immunofluorescence test for N-methyl d-aspartate receptor (NMDAR) antibodies and five other anti-neuronal autoantibodies of the immunoglobulin (Ig) classes IgA, IgG and IgM isotype. RESULTS: Anti-neuronal autoantibodies were found in 11...

Optimization of Diagnostic Elisa - Based Tests for the Detection of Auto-Antibodies Against Tumor Antigens in Human Serum

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Daria Štefatić

2008-08-01

Full Text Available Colorectal cancer is one of the most common cancer types worldwide and it continues to be a serious public health problem. Early detection and diagnosis are of great importance in cancer management. At present, diagnostic blood tests are based on the detection of tumor-associated markers such as carcinoembryonic antigen (CEA, the cancer antigen CA19-9 for gastrointestinal cancer, CA15-3 for breast cancer or CA125 for ovarian cancer. The lack of sensitivity and specificity of these markers prevents their general use in cancer screening of an average risk population. Therefore, new cancer biomarkers or better screening methods are necessary to improve the diagnostics of the disease. This study was directed to the optimization of a diagnostic, enzyme linked immunosorbent assay (ELISA based test to identify and validate new serum markers, such as extracellular Protein Kinase A (ecPKA and Nicotinamide A-Meth- yltransferase (NNMT. In this type of assay, the cancer antigens are quantified indirectly - by detecting the presence of auto-antibodies against tumor proteins in human serum. The result of the optimization and validation process was in the case of ecPKA a reproducible and stable assay. In case of NNMT the assay was probably not sensitive enough.

Utility of Novel Autoantibodies in the Diagnosis of Sjögren's Syndrome Among Patients With Dry Eye.

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Karakus, Sezen; Baer, Alan N; Agrawal, Devika; Gurakar, Merve; Massof, Robert W; Akpek, Esen K

2018-04-01

To investigate the value of 3 novel autoantibodies [salivary protein 1 (SP1), carbonic anhydrase 6 (CA6), and parotid secretory protein (PSP)] in differentiating Sjögren's syndrome (SS)-related dry eye from non-SS dry eye. Forty-six dry eye patients with SS (SS dry eye), 14 dry eye patients without SS (non-SS dry eye), and 25 controls were included. The 2012 American College of Rheumatology classification criteria were used for the diagnosis of SS. After a detailed review of systems, the Ocular Surface Disease Index questionnaire, Schirmer test without anesthesia, tear film breakup time, and ocular surface staining were performed to assess dry eye. All participants underwent serological testing using a commercially available finger prick kit. Thirty-seven patients with SS (80.4%) had a positive traditional autoantibody and 28 (60.9%) had a positive novel autoantibody. Traditional autoantibodies were absent in all non-SS dry eye patients and controls. Novel autoantibodies were present in 7/14 (50%) non-SS dry eye patients and 4/25 (16%) controls. Among 3 novel autoantibodies, anti-CA6 was significantly more prevalent in the SS and non-SS dry eye groups than in controls (52.2% vs. 42.9% vs. 8.0%, P = 0.001). Dry eye patients with positive anti-CA6 alone were significantly younger than patients with only traditional autoantibodies. Anti-CA6 was associated with worse dry eye signs and symptoms. Anti-CA6 was the most prevalent novel autoantibody in patients with dry eye, and was associated with younger age and more severe disease. Longitudinal studies are needed to determine whether anti-CA6 is a marker for early SS or perhaps another form of an autoimmune dry eye disease.

Low prevalence of liver-kidney microsomal autoantibodies of type 1 (LKM1) in hepatitis C seropositive subjects on Crete, Greece.

Science.gov (United States)

Drygiannakis, D; Lionis, C; Drygiannakis, I; Pappas, G; Kouroumalis, E

2001-01-01

Hepatitis C is a serious problem on the Greek island of Crete, where a high prevalence of antibodies against hepatitis C (anti-HCV) has recently been reported. This article reports the findings of a study carried out in Crete, which investigated the prevalence of serum autoantibodies in patients with chronic hepatitis C. One hundred and forty two patients (59 men and 83 women), who were found anti-HCV seropositive in two hospitals and two Primary Health Care Centres in Crete, were eligible. Sixty healthy blood donors (46 men, 14 women), which were negative to anti-HCV, were used as the control group. They were randomly selected from those attending Rethymnon Hospital. Autoantibodies were identified using the indirect immunofluorescence (IFL) technique on human epithelial cells from larynx cancer (HEp-2 cells), rat liver-kidney-stomach substrate (CT3) and Chrithidia Luciliae (CL). Serum autoantibodies were detected in 104 HCV patients, yielding an overall prevalence of 73.2%. The most frequent autoantibodies were antinuclear antibodies (ANA), positive in 72 patients (50.7%). Anti-smooth muscle antibodies (ASMA) were detected in 33 patients (23.2%). Only one patient was positive for LKM1 autoantibodies. No autoantibodies were found in 38 patients (26.7%). Autoantibodies were also found in 5 out of the 60 examined healthy blood donors (8.3%). Autoantibodies, mainly ANA and ASMA are very common in HCV seropositive patients from Crete. By contrast LKM1 autoantibodies are exceptionally rare in these patients.

Zn2+ chelation by serum albumin improves hexameric Zn2+-insulin dissociation into monomers after exocytosis.

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José A G Pertusa

Full Text Available β-cells release hexameric Zn2+-insulin into the extracellular space, but monomeric Zn2+-free insulin appears to be the only biologically active form. The mechanisms implicated in dissociation of the hexamer remain unclear, but they seem to be Zn2+ concentration-dependent. In this study, we investigate the influence of albumin binding to Zn2+ on Zn2+-insulin dissociation into Zn2+-free insulin and its physiological, methodological and therapeutic relevance. Glucose and K+-induced insulin release were analyzed in isolated mouse islets by static incubation and perifusion experiments in the presence and absence of albumin and Zn2+ chelators. Insulin tolerance tests were performed in rats using different insulin solutions with and without Zn2+ and/or albumin. Albumin-free buffer does not alter quantification by RIA of Zn2+-free insulin but strongly affects RIA measurements of Zn2+-insulin. In contrast, accurate determination of Zn2+-insulin was obtained only when bovine serum albumin or Zn2+ chelators were present in the assay buffer solution. Albumin and Zn2+ chelators do not modify insulin release but do affect insulin determination. Preincubation with albumin or Zn2+ chelators promotes the conversion of "slow" Zn2+-insulin into "fast" insulin. Consequently, insulin diffusion from large islets is ameliorated in the presence of Zn2+ chelators. These observations support the notion that the Zn2+-binding properties of albumin improve the dissociation of Zn2+-insulin into subunits after exocytosis, which may be useful in insulin determination, insulin pharmacokinetic assays and islet transplantation.

An Autoimmune Myositis-Overlap Syndrome Associated With Autoantibodies to Nuclear Pore Complexes

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Senécal, Jean-Luc; Isabelle, Catherine; Fritzler, Marvin J.; Targoff, Ira N.; Goldstein, Rose; Gagné, Michel; Raynauld, Jean-Pierre; Joyal, France; Troyanov, Yves; Dabauvalle, Marie-Christine

2014-01-01

Abstract Autoimmune myositis encompasses various myositis-overlap syndromes, each being identified by the presence of serum marker autoantibodies. We describe a novel myositis-overlap syndrome in 4 patients characterized by the presence of a unique immunologic marker, autoantibodies to nuclear pore complexes. The clinical phenotype was characterized by prominent myositis in association with erosive, anti-CCP, and rheumatoid factor-positive arthritis, trigeminal neuralgia, mild interstitial lung disease, Raynaud phenomenon, and weight loss. The myositis was typically chronic, relapsing, and refractory to corticosteroids alone, but remitted with the addition of a second immunomodulating drug. There was no clinical or laboratory evidence for liver disease. The prognosis was good with 100% long-term survival (mean follow-up 19.5 yr). By indirect immunofluorescence on HEp-2 cells, sera from all 4 patients displayed a high titer of antinuclear autoantibodies (ANA) with a distinct punctate peripheral (rim) fluorescent pattern of the nuclear envelope characteristic of nuclear pore complexes. Reactivity with nuclear pore complexes was confirmed by immunoelectron microscopy. In a cohort of 100 French Canadian patients with autoimmune myositis, the nuclear pore complex fluorescent ANA pattern was restricted to these 4 patients (4%). It was not observed in sera from 393 adult patients with systemic sclerosis (n = 112), mixed connective tissue disease (n = 35), systemic lupus (n = 94), rheumatoid arthritis (n = 45), or other rheumatic diseases (n = 107), nor was it observed in 62 normal adults. Autoantibodies to nuclear pore complexes were predominantly of IgG isotype. No other IgG autoantibody markers for defined connective tissue diseases or overlap syndromes were present, indicating a selective and highly focused immune response. In 3 patients, anti-nuclear pore complex autoantibody titers varied in parallel with myositis activity, suggesting a pathogenic

Insulin internalization in isolated rat hepatocytes

International Nuclear Information System (INIS)

Galan, J.; Trankina, M.; Noel, R.; Ward, W.

1990-01-01

This project was designed to determine whether neomycin, an aminoglycoside antibiotic, has a significant effect upon the pathways of ligand endocytosis in isolated rat hepatocytes. The pathways studied include receptor-mediated endocytosis and fluid-phase endocytosis. Neomycin causes a dose-dependent acceleration of 125 I-insulin internalization. Since fluid-phase endocytosis can also be a significant factor in 125 I-insulin internalization, lucifer yellow (LY), a marker for fluid-phase endocytosis, was incorporated into an assay similar to the 125 I-insulin internalization procedure. In the presence of 5 mM neomycin, a significant increase in LY uptake was evident at 0.2 and 0.4 mg/ml of LY. At 0.8 mg/ml, a decrease in LY uptake was observed. The increased rate of 125 I-insulin internalization in the presence of neomycin was intriguing. Since one action of neomycin is to inhibit phosphoinositidase C, it suggests that the phosphotidylinositol cycle may be involved in ligand internalization by hepatocytes. At low insulin concentrations, receptor-mediated uptake predominates. Fluid-phase uptake can become an important uptake route as insulin concentrations are increased. Since neomycin stimulates fluid-phase endocytosis, it must also be taken into account when measuring ligand internalization

Antinuclear Matrix Protein 2 Autoantibodies and Edema, Muscle Disease, and Malignancy Risk in Dermatomyositis Patients.

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Albayda, Jemima; Pinal-Fernandez, Iago; Huang, Wilson; Parks, Cassie; Paik, Julie; Casciola-Rosen, Livia; Danoff, Sonye K; Johnson, Cheilonda; Christopher-Stine, Lisa; Mammen, Andrew L

2017-11-01

Dermatomyositis (DM) patients typically present with proximal weakness and autoantibodies that are associated with distinct clinical phenotypes. We observed that DM patients with autoantibodies recognizing the nuclear matrix protein NXP-2 often presented with especially severe weakness. The aim of this study was to characterize the clinical features associated with anti-NXP-2 autoantibodies. There were 235 DM patients who underwent testing for anti-NXP-2 autoantibodies. Patient characteristics, including muscle strength, were compared between those with and without these autoantibodies. The number of cancer cases observed in anti-NXP-2-positive subjects was compared with the number expected in the general population. Of the DM patients, 56 (23.8%) were anti-NXP-2-positive. There was no significant difference in the prevalence of proximal extremity weakness in patients with and without anti-NXP-2. In contrast, anti-NXP-2-positive patients had more prevalent weakness in the distal arms (35% versus 20%; P = 0.02), distal legs (25% versus 8%; P edema (36% versus 19%; P = 0.01) than anti-NXP-2-negative patients. Five anti-NXP-2-positive subjects (9%) had cancer-associated myositis, representing a 3.68-fold increased risk (95% confidence interval 1.2-8.6) compared to the expected prevalence in the general population. In DM, anti-NXP-2 autoantibodies are associated with subcutaneous edema, calcinosis, and a muscle phenotype characterized by myalgia, proximal and distal weakness, and dysphagia. As anti-NXP-2-positive patients have an increased risk of cancer, we suggest that they undergo comprehensive cancer screening. © 2017, American College of Rheumatology.

Comparison and validation of ELISA assays for plasma insulin-like ...

African Journals Online (AJOL)

1 in the horse. ... accurate and precise of the three kits; the other two assays gave apparently much lower concentrations, with poor recovery of spiked recombinant human IGF-1 and unacceptably poor intra-assay coefficients of variation (CV).

The clinical phenotype associated with myositis-specific and associated autoantibodies: a meta-analysis revisiting the so-called antisynthetase syndrome.

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Lega, Jean-Christophe; Fabien, Nicole; Reynaud, Quitterie; Durieu, Isabelle; Durupt, Stéphane; Dutertre, Marine; Cordier, Jean-François; Cottin, Vincent

2014-09-01

To describe the clinical spectrum associated with aminoacyl-transfer RNA synthetase (ARS) autoantibodies in patients with idiopathic inflammatory myositis defined according to Peter and Bohan's criteria. Cohort studies were selected from MEDLINE and Embase up to August 2013. Two investigators independently extracted data on study design, patient characteristics, and clinical features (interstitial lung disease [ILD], fever, mechanic's hands [MH], Raynaud's phenomenon [RPh], arthralgia, sclerodactyly, cancer and dermatomyositis-specific rash) according to the presence of myositis-specific (anti-aminoacyl-transfer RNA synthetase [ARS], anti-signal recognition particle [anti-SRP] and anti-Mi2) and myositis-associated (anti-PM/Scl, anti-U1-RNP and anti-Ku) autoantibodies. 27 studies (3487 patients) were included in the meta-analysis. Arthralgia (75%, CI 67-81) and ILD (69%, CI 63-74) were the most prevalent clinical signs associated with anti-ARS autoantibodies. Anti-Mi2 and anti-SRP autoantibodies were associated with few extramuscular signs. ARS autoantibodies were identified in 13% of patients with cancer-associated myositis (5-25). Patients with non-anti-Jo1 ARS had greater odds of presenting fever (RR 0.63, CI 0.52-0.90) and ILD (RR 0.87, CI 0.81-0.93) compared to those with anti-Jo1 autoantibodies. The frequencies of myositis (RR 1.60, CI 1.38-1.85), arthralgia (RR 1.52, CI 1.32-1.76) and MH (RR 1.47, CI 1.11-1.94) were almost 50% higher in patients with anti-Jo1 compared to non-anti-Jo1 ARS autoantibodies. Patients with anti-PM/Scl differed from those with anti-ARS autoantibodies by a greater prevalence of RPh (RR 0.70, CI 0.53-0.94) and sclerodactyly (RR 0.47, CI 0.25-0.89). ILD was less frequent in patients with anti-U1-RNP autoantibodies (RR 3.35, CI 1.07-10.43). No difference was observed between anti-ARS and myositis-associated autoantibodies for other outcomes. The presence of anti-ARS autoantibodies delimits a heterogeneous subset of patients with a high

Thyroglobulin (Tg) Testing Revisited: Tg Assays, TgAb Assays, and Correlation of Results With Clinical Outcomes.

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Netzel, Brian C; Grebe, Stefan K G; Carranza Leon, B Gisella; Castro, M Regina; Clark, Penelope M; Hoofnagle, Andrew N; Spencer, Carole A; Turcu, Adina F; Algeciras-Schimnich, Alicia

2015-08-01

Measurement of thyroglobulin (Tg) by mass spectrometry (Tg-MS) is emerging as a tool for accurate Tg quantification in patients with anti-Tg autoantibodies (TgAbs). The objective of the study was to perform analytical and clinical evaluations of two Tg-MS assays in comparison with immunometric Tg assays (Tg-IAs) and Tg RIAs (Tg-RIAs) in a cohort of thyroid cancer patients. A total of 589 samples from 495 patients, 243 TgAb-/252 TgAb+, were tested by Beckman, Roche, Siemens-Immulite, and Thermo-Brahms Tg and TgAb assays, two Tg-RIAs, and two Tg-MS assays. The frequency of TgAb+ was 58%, 41%, 27%, and 39% for Roche, Beckman, Siemens-Immulite, and Thermo-Brahms, respectively. In TgAb- samples, clinical sensitivities and specificities of 100% and 74%-100%, respectively, were observed across all assays. In TgAb+ samples, all Tg-IAs demonstrated assay-dependent Tg underestimation, ranging from 41% to 86%. In TgAb+ samples, the use of a common cutoff (0.5 ng/mL) for the Tg-MS, three Tg-IAs, and the USC-RIA improved the sensitivity for the Tg-MSs and Tg-RIAs when compared with the Tg-IAs. In up to 20% of TgAb+ cases, Tg-IAs failed to detect Tg that was detectable by Tg-MS. In Tg-RIAs false-high biases were observed in TgAb+ samples containing low Tg concentrations. Tg-IAs remain the method of choice for Tg quantitation in TgAb- patients. In TgAb+ patients with undetectable Tg by immunometric assay, the Tg-MS will detect Tg in up to 20% additional cases. The Tg-RIA will detect Tg in approximately 35% cases, but a significant proportion of these will be clinical false-positive results. The undetectable Tg-MS seen in approximately 40% of TgAb+ cases in patients with disease need further evaluation.

Development of cytochrome P450 2D6-specific LKM-autoantibodies following liver transplantation for Wilson's disease -- possible association with a steroid-resistant transplant rejection episode.

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Lohse, A W; Obermayer-Straub, P; Gerken, G; Brunner, S; Altes, U; Dienes, H P; Manns, M P; Meyer zum Büschenfelde, K H

1999-07-01

Antibodies to cytochrome P450 2D6, also known as LKM1-autoantibodies, are characteristic for a subgroup of patients with autoimmune hepatitis, but can also occasionally be found in hepatitis C. We observed the occurrence of LKM1-autoantibodies 4 months after liver transplantation for Wilson's disease, in close association with a steroid-resistant rejection episode, in the absence of evidence for autoimmune hepatitis or hepatitis C. Sera from several time points prior to and following transplantation were tested for LKM-reactivity by immunofluorescence, ELISA and Western blotting. Antigen specificity was confirmed by Western blotting analysis on different cytochrome P450 isoenzymes. The absence of viral hepatitis C and hepatitis G virus infection was confirmed by polymerase chain reaction. The serum of the organ donor was also tested. All the sera prior to transplantation and up to 4 months after transplantation were LKM-negative by all assay systems used. In the course of a steroid-resistant rejection episode at this time, the patient developed LKM antibodies at high titre (70% in inhibition ELISA) and has remained positive since (now more than 4 years). Reactivity was exclusively to the cytochrome isoenzyme 2D6. Hepatitis C infection never occurred, but hepatitis G was transiently present many years prior to transplantation. The donor serum was negative for all autoantibodies and for hepatitis C and G virus infection. We here describe a patient developing LKM1-autoantibodies without evidence of autoimmune or viral hepatitis. The close temporal association with a transplant rejection episode suggests immunological mechanisms of rejection together with hepatocellular injury as a pathogenetic mechanism.

Ameliorative effects of polyunsaturated fatty acids against palmitic acid-induced insulin resistance in L6 skeletal muscle cells

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Sawada Keisuke

2012-03-01

Full Text Available Abstract Background Fatty acid-induced insulin resistance and impaired glucose uptake activity in muscle cells are fundamental events in the development of type 2 diabetes and hyperglycemia. There is an increasing demand for compounds including drugs and functional foods that can prevent myocellular insulin resistance. Methods In this study, we established a high-throughput assay to screen for compounds that can improve myocellular insulin resistance, which was based on a previously reported non-radioisotope 2-deoxyglucose (2DG uptake assay. Insulin-resistant muscle cells were prepared by treating rat L6 skeletal muscle cells with 750 μM palmitic acid for 14 h. Using the established assay, the impacts of several fatty acids on myocellular insulin resistance were determined. Results In normal L6 cells, treatment with saturated palmitic or stearic acid alone decreased 2DG uptake, whereas unsaturated fatty acids did not. Moreover, co-treatment with oleic acid canceled the palmitic acid-induced decrease in 2DG uptake activity. Using the developed assay with palmitic acid-induced insulin-resistant L6 cells, we determined the effects of other unsaturated fatty acids. We found that arachidonic, eicosapentaenoic and docosahexaenoic acids improved palmitic acid-decreased 2DG uptake at lower concentrations than the other unsaturated fatty acids, including oleic acid, as 10 μM arachidonic acid showed similar effects to 750 μM oleic acid. Conclusions We have found that polyunsaturated fatty acids, in particular arachidonic and eicosapentaenoic acids prevent palmitic acid-induced myocellular insulin resistance.

Low prevalence of liver-kidney microsomal autoantibodies of type 1 (LKM1 in hepatitis C seropositive subjects on Crete, Greece

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Pappas Georgios

2001-06-01

Full Text Available Abstract Background Hepatitis C is a serious problem on the Greek island of Crete, where a high prevalence of antibodies against hepatitis C (anti-HCV has recently been reported. This article reports the findings of a study carried out in Crete, which investigated the prevalence of serum autoantibodies in patients with chronic hepatitis C. Patients and Methods One hundred and forty two patients (59 men and 83 women, who were found anti-HCV seropositive in two hospitals and two Primary Health Care Centres in Crete, were eligible. Sixty healthy blood donors (46 men, 14 women, which were negative to anti-HCV, were used as the control group. They were randomly selected from those attending Rethymnon Hospital. Autoantibodies were identified using the indirect immunofluorescence (IFL technique on human epithelial cells from larynx cancer (HEp-2 cells, rat liver-kidney-stomach substrate (CT3 and Chrithidia Luciliae (CL. Results Serum autoantibodies were detected in 104 HCV patients, yielding an overall prevalence of 73.2%. The most frequent autoantibodies were antinuclear antibodies (ANA, positive in 72 patients (50.7%. Anti-smooth muscle antibodies (ASMA were detected in 33 patients (23.2%. Only one patient was positive for LKM1 autoantibodies. No autoantibodies were found in 38 patients (26.7%. Autoantibodies were also found in 5 out of the 60 examined healthy blood donors (8.3%. Conclusions Autoantibodies, mainly ANA and ASMA are very common in HCV seropositive patients from Crete. By contrast LKM1 autoantibodies are exceptionally rare in these patients.

Autoantibody to MDM2: A Potential Serological Marker of Systemic Lupus Erythematosus

OpenAIRE

Liu, Yuan; Dai, Liping; Liu, Weihong; Shi, Guixiu; Zhang, Jianying

2015-01-01

Introduction. Systemic lupus erythematosus (SLE) is one of the systemic autoimmune diseases characterized by the polyclonal autoantibody production. The human homologue of the mouse double minute 2 (MDM2) is well known as the negative regulator of p53. MDM2 has been reported to be overexpressed in SLE animal model and to promote SLE. Since abnormally expressed proteins can induce autoimmune response, anti-MDM2 autoantibody was examined in SLE patients. Methods. Anti-MDM2 antibody in sera from...

A study of the epitopes on steroid 21-hydroxylase recognized by autoantibodies in patients with or without Addison's disease

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Volpato, M; Prentice, L; Chen, S; Betterle, C; Rees Smith, B; Furmaniak, J

1998-01-01

Steroid 21-hydroxylase (21-OH) autoantibodies are found in patients with autoimmune Addison's disease (AAD), either isolated or associated with autoimmune polyglandular syndrome (APS) type I and II and in adrenal-cortex autoantibody (ACA)-positive patients without AAD. In order to assess any differences in the 21-OH autoantibodies in these different patient groups, we have studied their reactivity with different epitopes on 21-OH using full length and modified 35S-labelled 21-OH proteins produced in an in vitro transcription/translation system. There were no major differences in the pattern of autoantibody reactivity with the different modified 21-OH proteins in patients with isolated AAD or with APS types I and II, and in 21-OH autoantibody-positive patients with clinical AAD, subclinical AAD and those maintaining a normal adrenal function. Our studies also indicate that the main epitopes for 21-OH autoantibodies in patients with different forms of autoimmune adrenal disease are located in the C-terminal end and in a central region of 21-OH. PMID:9486414

Thyrotropin-Blocking Autoantibodies and Thyroid-Stimulating Autoantibodies: Potential Mechanisms Involved in the Pendulum Swinging from Hypothyroidism to Hyperthyroidism or Vice Versa

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Rapoport, Basil

2013-01-01

Background Thyrotropin receptor (TSHR) antibodies that stimulate the thyroid (TSAb) cause Graves' hyperthyroidism and TSHR antibodies which block thyrotropin action (TBAb) are occasionally responsible for hypothyroidism. Unusual patients switch from TSAb to TBAb (or vice versa) with concomitant thyroid function changes. We have examined case reports to obtain insight into the basis for “switching.” Summary TBAb to TSAb switching occurs in patients treated with levothyroxine (LT4); the reverse switch (TBAb to TSAb) occurs after anti-thyroid drug therapy; TSAb/TBAb alterations may occur during pregnancy and are well recognized in transient neonatal thyroid dysfunction. Factors that may impact the shift include: (i) LT4 treatment, usually associated with decreased thyroid autoantibodies, in unusual patients induces or enhances thyroid autoantibody levels; (ii) antithyroid drug treatment decreases thyroid autoantibody levels; (iii) hyperthyroidism can polarize antigen-presenting cells, leading to impaired development of regulatory T cells, thereby compromising control of autoimmunity; (iv) immune-suppression/hemodilution reduces thyroid autoantibodies during pregnancy and rebounds postpartum; (v) maternally transferred IgG transiently impacts thyroid function in neonates until metabolized; (vi) a Graves' disease model involving immunizing TSHR-knockout mice with mouse TSHR-adenovirus and transfer of TSHR antibody-secreting splenocytes to athymic mice demonstrates the TSAb to TBAb shift, paralleling the outcome of maternally transferred “term limited” TSHR antibodies in neonates. Finally, perhaps most important, as illustrated by dilution analyses of patients' sera in vitro, TSHR antibody concentrations and affinities play a critical role in switching TSAb and TBAb functional activities in vivo. Conclusions Switching between TBAb and TSAb (or vice versa) occurs in unusual patients after LT4 therapy for hypothyroidism or anti-thyroid drug treatment for Graves

Clinical Significance of Autoantibodies in Some Thyroid Disorders

International Nuclear Information System (INIS)

Choi, Sung Kyu; Han, Sang Ho; Kim, Young Ju; Song, Jun Ho; Lee, Man Ho; Chung, Eul Sun; Lee, Sang Jong

1984-01-01

Clinical measurement of thyroid autoantibodies in sera of some thyroid disorders have been widely applied since about twenty years ago. We investigated the incidence and titers of both antimicrosomal and antithyroglobulin antibodies in forty eight cases with controls and one hundred and thirty three patients with some form of thyroid disorders. The results were as follows; 1) In controls, antimicrosomal antibodies were positive in 2% but antithyroglobulin antibodies were all negative. 2) In a series of one hundred and thirty three patients with thyroid disease, antimicrosomal antibodies were positive in 44% but antithyroglobulin antibodies were positive in only 15%. 3) The rate disclosing the positive results of antimicrosomal antibodies were 71% in Hashimoto disease, 60% in Graves' disease, and 38% in primary hypothyroidism, respectively. On the other hand, the positive results of antithyroglobulin antibodies showed 21% in Graves' disease, 19% in primary hypothyroidism, and 18% in Hashimoto, disease, respectively. Though there were relatively high rate of both antimicrosomal and antithyroglobulin antibodies in patients with nodular goiter, they were only seven cases in our series. 4) The rate with the extremely high titers of antimicrosomal and antithyroglobulin antibodies (>1 : 160 2 ) was 83% and 67% in Hashimoto's disease, 50% and 67% in primary hypothyroidism, and 41% and 18% in Graves' disease. Accordingly, the thyroid autoantibodies, were commonly found higher positive rate in patients with Hashimoto disease, primary hypothyroidism, and Graves' disease. Among these disorders, the extremely high positive rate of the thyroid autoantibodies was found in patients with Hashimoto's disease.

Role of Natural Autoantibodies in Ugandans With Rheumatic Heart Disease and HIV☆

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Huck, Daniel M.; Okello, Emmy; Mirembe, Grace; Ssinabulya, Isaac; Zidar, David A.; Silverman, Gregg J.; Getu, Lelise; Nowacki, Amy S.; Calabrese, Leonard H.; Salata, Robert A.; Longenecker, Chris T.

2016-01-01

Background Rheumatic heart disease (RHD) and HIV are prevalent diseases in sub-Saharan Africa, but little is known about their potential interrelationships. The objective of this study was to assess the prevalence of protective natural autoantibodies among patients with RHD in Uganda, and to determine whether the levels of these autoantibodies are affected by HIV status. Methods Participants were grouped according to RHD and HIV status. The three control groups (RHD − HIV −, RHD − HIV +, RHD + HIV −) were age-matched to the RHD + HIV + participants. All participants underwent HIV testing and echocardiography to evaluate for RHD. Natural autoantibody levels reactive with phosphorylcholine (PC) and malondialdehyde (MDA) were measured. Findings We enrolled 220 participants; 21 with both RHD and HIV. Ages ranged from 10 to 60 years, with female predominance (144/220, 65%). After adjusting for age and gender, HIV infection and RHD were each associated with low IgM anti-PC (HIV: p disease. PMID:27077123

Autoantibodies Against Carbonic Anhydrase I and II in Patients with Acute Myeloid Leukemia

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Ahmet Menteşe

2017-12-01

Full Text Available Objective: Cancer, one of the principal causes of death, is a global social health problem. Autoantibodies developed against the organism’s self-antigens are detected in the sera of subjects with cancer. In recent years carbonic anhydrase (CA I and II autoantibodies have been shown in some autoimmune diseases and carcinomas, but the mechanisms underlying this immune response have not yet been explained. The aim of this study was to evaluate CA I and II autoantibodies in patients with acute myeloid leukemia (AML and to provide a novel perspective regarding the autoimmune basis of the disease. Materials and Methods: Anti-CA I and II antibody levels were investigated using ELISA in serum samples from 30 patients with AML and 30 healthy peers. Results: Anti-CA I and II antibody titers in the AML group were significantly higher compared with the control group (p=0.0001 and 0.018, respectively. A strong positive correlation was also determined between titers of anti-CA I and II antibodies (r=0.613, p=0.0001. Conclusion: Our results suggest that these autoantibodies may be involved in the pathogenesis of AML. More extensive studies are now needed to reveal the entire mechanism.

Cytokines in relation to autoantibodies before onset of symptoms for systemic lupus erythematosus.

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Eriksson, C; Rantapää-Dahlqvist, S

2014-06-01

A number of cytokines and chemokines were analysed and related to autoantibodies in blood samples pre-dating the onset of symptoms of systemic lupus erythematosus. Thirty-five patients with systemic lupus erythematosus (American College of Rheumatology criteria) were identified as having donated blood samples, prior to symptom onset, to the Biobank of northern Sweden. Altogether, 140 age- and sex-matched controls were also identified. The concentrations of interferon-α, interleukin-4, interleukin-9, interleukin-10, interferon inducible protein-10 and monocyte chemotactic protein-1 were analysed using multiplex technology and related to autoantibodies (ANA, ENA, anti-dsDNA and anti-histone antibodies) analysed from the same blood sample. The interferon-γ inducible protein-10 levels were higher in the pre-symptomatic individuals than in controls (p systemic lupus erythematosus. An increased concentration of interferon-γ inducible protein-10 pre-dated the onset of systemic lupus erythematosus and was related to autoantibodies before the onset of disease. The levels of interferon-γ inducible protein-10 and interferon-α were correlated. These findings support the proposal that the interferon system is important early in the pathogenesis of systemic lupus erythematosus and autoantibody formation. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

Astrocytic autoantibody of neuromyelitis optica (NMO-IgG) binds to aquaporin-4 extracellular loops, monomers, tetramers and high order arrays

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Iorio, Raffaele; Fryer, James P.; Hinson, Shannon R.; Fallier-Becker, Petra; Wolburg, Hartwig; Pittock, Sean J.; Lennon, Vanda A.

2012-01-01

The principal central nervous system (CNS) water channel, aquaporin-4 (AQP4), is confined to astrocytic and ependymal membranes and is the target of a pathogenic autoantibody, neuromyelitis optica (NMO)-IgG. This disease-specific autoantibody unifies a spectrum of relapsing CNS autoimmune inflammatory disorders of which NMO exemplifies the classic phenotype. Multiple sclerosis and other immune-mediated demyelinating disorders of the CNS lack a distinctive biomarker. Two AQP4 isoforms, M1 and M23, exist as homotetrameric and heterotetrameric intramembranous particles (IMPs). Orthogonal arrays of predominantly M23 particles (OAPs) are an ultrastructural characteristic of astrocytic membranes. We used high-titered serum from 32 AQP4-IgG-seropositive patients and 85 controls to investigate the nature and molecular location of AQP4 epitopes that bind NMO-IgG, and the influence of supramolecular structure. NMO-IgG bound to denatured AQP4 monomers (68% of cases), to native tetramers and high order arrays (90% of cases), and to AQP4 in live cell membranes (100% of cases). Disease-specific epitopes reside in extracellular loop C more than in loops A or E. IgG binding to intracellular epitopes lacks disease specificity. These observations predict greater disease specificity and sensitivity for tissue-based and cell-based serological assays employing “native” AQP4 than assays employing denatured AQP4 and fragments. NMO-IgG binds most avidly to plasma membrane surface AQP4 epitopes formed by loop interactions within tetramers and by intermolecular interactions within high order structures. The relative abundance and localization of AQP4 high order arrays in distinct CNS regions may explain the variability in clinical phenotype of NMO spectrum disorders. PMID:22906356

Plasma phospholipid transfer protein activity is related to insulin resistance : impaired acute lowering by insulin in obese Type II diabetic patients

NARCIS (Netherlands)

Riemens, SC; van Tol, A; Sluiter, WJ; Dullaart, RPF

Cholesteryl ester transfer protein (CETP) and phospholipid transfer protein (PLTP) have important functions in high density lipoprotein (HDL) metabolism. We determined the association of plasma CETP and PLTP activities (measured with exogenous' substrate assays) with insulin resistance, plasma

Cramp-fasciculation syndrome in patients with and without neural autoantibodies.

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Liewluck, Teerin; Klein, Christopher J; Jones, Lyell K

2014-03-01

We investigated the clinical, electrophysiological and neural autoantibody characteristics in cramp-fasciculation syndrome (CFS) patients. We reviewed Mayo Clinic records from 2000 to 2011 to identify clinically defined CFS patients who underwent neural autoantibody testing. Stored sera of patients who tested positive for antibodies to voltage-gated potassium channel complex (VGKC complex) were analyzed further for leucine-rich glioma-inactivated 1 (LGI1) or contactin-associated protein-2 immunoglobulin G (CASPR2-IgG) antibodies. Thirty-seven patients were identified. Twelve were seropositive for neural autoantibodies. Clinical manifestations were similar in seropositive and seronegative patients, although central and autonomic neuronal hyperexcitability symptoms were more common in seropositive cases. No patients had a malignancy. Repetitive tibial nerve stimulation at 10 Hz revealed longer afterdischarges in seropositive patients. Two of 7 patients with VGKC-complex autoimmunity demonstrated LGI1 or CASPR2-IgG antibodies. Only 2 of 12 seropositive patients required immunotherapy. VGKC-complex autoimmunity occurs in a minority of CFS patients. Antibody positivity was associated with extramuscular manifestations, typically without malignancy. Target antigens within the VGKC complex remain unknown in most patients. Published 2013 by Wiley Periodicals, Inc. This article is a US Government work and, as such, is in the public domain in the United States of America.

Autoantibodies to neuronal antigens in children with focal epilepsy and no prima facie signs of encephalitis.

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Borusiak, Peter; Bettendorf, Ulrich; Wiegand, Gert; Bast, Thomas; Kluger, Gerhard; Philippi, Heike; Münstermann, Dieter; Bien, Christian G

2016-07-01

There is increasing awareness of neuronal autoantibodies and their impact on the pathogenesis of epilepsy. We investigated children with focal epilepsy in order to provide an estimate of autoantibody frequency within a pediatric population without prima facie evidence of encephalitis using a broad panel of autoantibodies. This was done to assess the specificity of antibodies and to see whether antibodies might be of modifying influence on the course of focal epilepsies. We searched for autoantibodies in 124 patients with focal epilepsy (1-18 years; mean 10; 6 years). Sera were tested using a broad panel of surface and intracellular antigens. We found autoantibodies in 5/124 patients (4%): high-positive GAD65 antibodies (n = 1), low-positive GAD65 antibodies (N = 1), VGKC complex antibodies not reactive with LGI1 or CASPR2 (n = 3). We did not find any distinctive features distinguishing antibody positive patients from those without antibodies. The antibodies found in this cohort are probably neither disease-specific nor pathogenic. This has been suggested before for these antigenic targets. Moreover, they do not seem to modify disease severity in the antibody-positive epilepsy patients. Copyright © 2016 European Paediatric Neurology Society. Published by Elsevier Ltd. All rights reserved.

Scoparia dulcis (SDF7) endowed with glucose uptake properties on L6 myotubes compared insulin.

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Beh, Joo Ee; Latip, Jalifah; Abdullah, Mohd Puad; Ismail, Amin; Hamid, Muhajir

2010-05-04

Insulin stimulates glucose uptake and promotes the translocation of glucose transporter 4 (Glut 4) to the plasma membrane on L6 myotubes. The aim of this study is to investigate affect of Scoparia dulcis Linn water extracts on glucose uptake activity and the Glut 4 translocation components (i.e., IRS-1, PI 3-kinase, PKB/Akt2, PKC and TC 10) in L6 myotubes compared to insulin. Extract from TLC fraction-7 (SDF7) was used in this study. The L6 myotubes were treated by various concentrations of SDF7 (1 to 50 microg/ml) and insulin (1 to 100 nM). The glucose uptake activities of L6 myotubes were evaluated using 2-Deoxy-D-glucose uptake assay in with or without fatty acid-induced medium. The Glut 4 translocation components in SDF7-treated L6 myotubes were detected using immunoblotting and quantified by densitometry compared to insulin. Plasma membrane lawn assay and glycogen colorimetry assay were carried out in SDF7- and insulin-treated L6 myotubes in this study. Here, our data clearly shows that SDF7 possesses glucose uptake properties on L6 myotubes that are dose-dependent, time-dependent and plasma membrane Glut 4 expression-dependent. SDF7 successfully stimulates glucose uptake activity as potent as insulin at a maximum concentration of 50 microg/ml at 480 min on L6 myotubes. Furthermore, SDF7 stimulates increased Glut 4 expression and translocation to plasma membranes at equivalent times. Even in the insulin resistance stage (free fatty acids-induced), SDF7-treated L6 myotubes were found to be more capable at glucose transport than insulin treatment. Thus, we suggested that Scoparia dulcis has the potential to be categorized as a hypoglycemic medicinal plant based on its good glucose transport properties. (c) 2010 Elsevier Ireland Ltd. All rights reserved.

Immunotherapy trials for type 1 diabetes: the contribution of George Eisenbarth.

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Skyler, Jay S; Pugliese, Alberto

2013-06-01

Type 1 diabetes (T1D) results from the autoimmune destruction of pancreatic β-cells, and as such it should respond to immunotherapy. George Eisenbarth gave many significant contributions to this field. He has been involved at some level in most immunotherapy trials during the past three decades. He was among the pioneers who attempted immunotherapy approaches in patients with recent-onset T1D. In the early 1980s he began studying relatives of those with the disease, leading to the concept that T1D was a chronic autoimmune disease, in which islet autoimmune responses would silently destroy β-cells and cause progressive impairment of insulin secretion, years to months before a diagnosis was made. Consequently, he was one of the first to attempt immune intervention in people at high risk of T1D. Throughout his career he developed autoantibody assays and predictive models (which included metabolic testing and later genetics) to identify individuals at risk of T1D. He provided seminal intellectual contributions and critical tools for prevention trials. His focus on insulin as a critical autoantigen led to multiple prevention trials, including the Diabetes Prevention Trial-Type 1 (DPT-1), which studied both parenteral and oral insulin. In the DPT-1 Oral Insulin Trial, a cohort with higher levels of insulin autoantibodies was identified that appeared to have delayed disease progression. Type 1 Diabetes TrialNet is conducting a new trial to verify or refute this observation. Moreover, George identified and tested in the mouse small molecules that block or modulate presentation of a key insulin peptide and in turn prevent the activation of insulin-specific T-lymphocytes. Thus, we believe his greatest contribution is yet to come, as in the near future we should see this most recent work translate into clinical trials.

Cluster analysis of autoantibodies in 852 patients with systemic lupus erythematosus from a single center.

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Artim-Esen, Bahar; Çene, Erhan; Şahinkaya, Yasemin; Ertan, Semra; Pehlivan, Özlem; Kamali, Sevil; Gül, Ahmet; Öcal, Lale; Aral, Orhan; Inanç, Murat

2014-07-01

Associations between autoantibodies and clinical features have been described in systemic lupus erythematosus (SLE). Herein, we aimed to define autoantibody clusters and their clinical correlations in a large cohort of patients with SLE. We analyzed 852 patients with SLE who attended our clinic. Seven autoantibodies were selected for cluster analysis: anti-DNA, anti-Sm, anti-RNP, anticardiolipin (aCL) immunoglobulin (Ig)G or IgM, lupus anticoagulant (LAC), anti-Ro, and anti-La. Two-step clustering and Kaplan-Meier survival analyses were used. Five clusters were identified. A cluster consisted of patients with only anti-dsDNA antibodies, a cluster of anti-Sm and anti-RNP, a cluster of aCL IgG/M and LAC, and a cluster of anti-Ro and anti-La antibodies. Analysis revealed 1 more cluster that consisted of patients who did not belong to any of the clusters formed by antibodies chosen for cluster analysis. Sm/RNP cluster had significantly higher incidence of pulmonary hypertension and Raynaud phenomenon. DsDNA cluster had the highest incidence of renal involvement. In the aCL/LAC cluster, there were significantly more patients with neuropsychiatric involvement, antiphospholipid syndrome, autoimmune hemolytic anemia, and thrombocytopenia. According to the Systemic Lupus International Collaborating Clinics damage index, the highest frequency of damage was in the aCL/LAC cluster. Comparison of 10 and 20 years survival showed reduced survival in the aCL/LAC cluster. This study supports the existence of autoantibody clusters with distinct clinical features in SLE and shows that forming clinical subsets according to autoantibody clusters may be useful in predicting the outcome of the disease. Autoantibody clusters in SLE may exhibit differences according to the clinical setting or population.

Natural IgG autoantibodies are abundant and ubiquitous in human sera, and their number is influenced by age, gender, and disease.

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Eric P Nagele

Full Text Available The presence of self-reactive IgG autoantibodies in human sera is largely thought to represent a breakdown in central tolerance and is typically regarded as a harbinger of autoimmune pathology. In the present study, immune-response profiling of human serum from 166 individuals via human protein microarrays demonstrates that IgG autoantibodies are abundant in all human serum, usually numbering in the thousands. These IgG autoantibodies bind to human antigens from organs and tissues all over the body and their serum diversity is strongly influenced by age, gender, and the presence of specific diseases. We also found that serum IgG autoantibody profiles are unique to an individual and remarkably stable over time. Similar profiles exist in rat and swine, suggesting conservation of this immunological feature among mammals. The number, diversity, and apparent evolutionary conservation of autoantibody profiles suggest that IgG autoantibodies have some important, as yet unrecognized, physiological function. We propose that IgG autoantibodies have evolved as an adaptive mechanism for debris-clearance, a function consistent with their apparent utility as diagnostic indicators of disease as already established for Alzheimer's and Parkinson's diseases.

Comparison of Serum Autoantibodies to Desmogleins I, III in Patients with Oral Lichen Planus and Healthy Controls.

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Gholizadeh, Narges; Khoini Poorfar, Hossein; TaghaviZenouz, Ali; Vatandoost, Masoumeh; Mehdipour, Masoumeh

2015-01-01

Lichen planus is a mucocutaneous disease which is relatively common and in 30-70% of patients, mucosal lesions can be seen and known as a precancerous lesion but its etiology is not completely understood. Desmogleins I and III are the main desmosomal transmembrane proteins. These proteins have been identified as the autoantigen of the autoimmune disease. The aim of this study was evaluation of serum autoantibodies against desmogleins Ι, ΙΙΙ in oral lichen planus . We attempted to determine the etiology of this disease with evaluation of these serum factors. Thirty-five patients with oral lichen planus and 35 healthy controls were recruited and tested for serum autoantibodies against desmogleins Ι, ΙΙΙ and indirect immunofluorescence also performed. Data were analyzed by statistical-analytical methods (Independent sample t -test) with using the SPSS.15 software. Serum autoantibody against desmoglein Ι had no significant difference in the two groups ( P =0.31 ) but significant increase in serum autoantibody to desmoglein ΙΙΙ was found in patients with oral lichen planus ( P =0.00) . It seems that autoantibody against desmoglein III has a significant role in the pathogenesis of oral lichen planus.

Peroxynitrite modified DNA presents better epitopes for anti-DNA autoantibodies in diabetes type 1 patients.

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Tripathi, Prashant; Moinuddin; Dixit, Kiran; Mir, Abdul Rouf; Habib, Safia; Alam, Khursheed; Ali, Asif

2014-07-01

Peroxynitrite (ONOO(-)), formed by the reaction between nitric oxide (NO) and superoxide (O2(-)), has been implicated in the etiology of numerous disease processes. Peroxynitrite interacts with DNA via direct oxidative reactions or via indirect radical-mediated mechanism. It can inflict both oxidative and nitrosative damages on DNA bases, generating abasic sites, resulting in the single strand breaks. Plasmid pUC 18 isolated from Escherichiacoli was modified with peroxynitrite, generated by quenched flow process. Modifications incurred in plasmid DNA were characterized by ultraviolet and fluorescence spectroscopy, circular dichroism, HPLC and melting temperature studies. Binding characteristics and specificity of antibodies from diabetes patients were analyzed by direct binding and inhibition ELISA. Peroxynitrite modification of pUC 18 plasmid resulted in the formation of strand breaks and base modification. The major compound formed when peroxynitrite reacted with DNA was 8-nitroguanine, a specific marker for peroxynitrite induced DNA damage in inflamed tissues. The concentration of 8-nitroguanine was found to be 3.8 μM. Sera from diabetes type 1 patients from different age groups were studied for their binding to native and peroxynitrite modified plasmid. Direct binding and competitive-inhibition ELISA results showed higher recognition of peroxynitrite modified plasmid, as compared to the native form, by auto-antibodies present in diabetes patients. The preferential recognition of modified plasmid by diabetes autoantibodies was further reiterated by gel shift assay. Experimentally induced anti-peroxynitrite-modified plasmid IgG was used as a probe to detect nitrosative lesions in the DNA isolated from diabetes patients. Copyright © 2014 Elsevier Inc. All rights reserved.

An autoantibody against N{sup {epsilon}}-(carboxyethyl)lysine (CEL): Possible involvement in the removal of CEL-modified proteins by macrophages

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Mera, Katsumi [Department of Biopharmaceutics, Graduate School of Pharmaceutical Sciences, Kumamoto University, Kumamoto (Japan); Nagai, Ryoji, E-mail: nagai-883@umin.ac.jp [Department of Food and Nutrition, Laboratory of Nutritional Science and Biochemistry, Japan Women' s University, Tokyo (Japan); Takeo, Kazuhiro; Izumi, Miyoko [Department of Biopharmaceutics, Graduate School of Pharmaceutical Sciences, Kumamoto University, Kumamoto (Japan); Maruyama, Toru [Department of Biopharmaceutics, Graduate School of Pharmaceutical Sciences, Kumamoto University, Kumamoto (Japan); Center for Clinical Pharmaceutical Science, Kumamoto University, Kumamoto (Japan); Otagiri, Masaki [Department of Biopharmaceutics, Graduate School of Pharmaceutical Sciences, Kumamoto University, Kumamoto (Japan); Faculty of Pharmaceutical Sciences, Sojo University, Kumamoto (Japan)

2011-04-08

Highlights: {yields} A higher amount of autoantibody against CEL than that of other AGEs was observed in human plasma. {yields} The purified human anti-CEL autoantibody specifically reacted with CEL. {yields} Anti-CEL antibody accelerated the uptake of {sup 125}I-CEL-HSA by macrophage in vitro. {yields} Endocytic uptake of {sup 125}I-CEL-HSA by mice liver was accelerated in the presence of anti-CEL antibody. -- Abstract: Advanced glycation end products (AGEs) are believed to play a significant role in the development of diabetic complications. In this study, we measured the levels of autoantibodies against several AGE structures in healthy human plasma and investigated the physiological role of the autoantibodies. A high titer of the autoantibody against N{sup {epsilon}}-(carboxyethyl)lysine (CEL) was detected in human plasma compared with other AGE structures such as CML and pentosidine. The purified human anti-CEL autoantibody reacted with CEL-modified human serum albumin (CEL-HSA), but not CML-HSA. A rabbit polyclonal anti-CEL antibody, used as a model autoantibody against CEL, accelerated the uptake of CEL-HSA by macrophages, but did not enhance the uptake of native HSA. Furthermore, when {sup 125}I-labeled CEL-HSA was injected into the tail vein of mice, accumulation of {sup 125}I-CEL-HSA in the liver was accelerated by co-injection of the rabbit anti-CEL antibody. These results demonstrate that the autoantibody against CEL in plasma may play a role in the macrophage uptake of CEL-modified proteins.

The Level of Autoantibodies Targeting Eukaryote Translation Elongation Factor 1 α1 and Ubiquitin-Conjugating Enzyme 2L3 in Nondiabetic Young Adults

Directory of Open Access Journals (Sweden)

Eunhee G. Kim

2016-01-01

Full Text Available BackgroundThe prevalence of novel type 1 diabetes mellitus (T1DM antibodies targeting eukaryote translation elongation factor 1 alpha 1 autoantibody (EEF1A1-AAb and ubiquitin-conjugating enzyme 2L3 autoantibody (UBE2L3-AAb has been shown to be negatively correlated with age in T1DM subjects. Therefore, we aimed to investigate whether age affects the levels of these two antibodies in nondiabetic subjects.MethodsEEF1A1-AAb and UBE2L3-AAb levels in nondiabetic control subjects (n=150 and T1DM subjects (n=101 in various ranges of age (18 to 69 years were measured using an enzyme-linked immunosorbent assay. The cutoff point for the presence of each autoantibody was determined based on control subjects using the formula: [mean absorbance+3×standard deviation].ResultsIn nondiabetic subjects, there were no significant correlations between age and EEF1A1-AAb and UBE2L3-AAb levels. However, there was wide variation in EEF1A1-AAb and UBE2L3-AAb levels among control subjects <40 years old; the prevalence of both EEF1A1-AAb and UBE2L3-AAb in these subjects was 4.4%. When using cutoff points determined from the control subjects <40 years old, the prevalence of both autoantibodies in T1DM subjects was decreased (EEFA1-AAb, 15.8% to 8.9%; UBE2L3-AAb, 10.9% to 7.9% when compared to the prevalence using the cutoff derived from the totals for control subjects.ConclusionThere was no association between age and EEF1A1-AAb or UBE2L3-AAb levels in nondiabetic subjects. However, the wide variation in EEF1A1-AAb and UBE2L3-AAb levels apparent among the control subjects <40 years old should be taken into consideration when determining the cutoff reference range for the diagnosis of T1DM.

Prevalence of autoantibodies in the course of Gaucher disease type 1: A multicenter study comparing Gaucher disease patients to healthy subjects.

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Serratrice, Christine; Bensalah, Nesma; Penaranda, Guillaume; Bardin, Nathalie; Belmatoug, Nadia; Masseau, Agathe; Rose, Christian; Lidove, Olivier; Camou, Fabrice; Maillot, François; Leguy, Vanessa; Magy-Bertrand, Nadine; Marie, Isabelle; Cherin, Patrick; Bengherbia, Monia; Carballo, Sebastian; Boucraut, José; Serratrice, Jacques; Berger, Marc; Verrot, Denis

2018-01-01

Type 1 Gaucher disease may be related to the presence of autoantibodies. Their clinical significance is questioned. Primary endpoint was to compare the prevalence of autoantibodies in type 1 Gaucher disease patients with healthy subjects, seeking correlations with autoimmune characteristics. Secondary endpoints were to determine whether patients with autoantibodies reported autoimmunity-related symptoms and if genotype, splenectomy or treatment influenced autoantibodies presence. Type 1 Gaucher disease patients and healthy volunteers were included in this national multicenter exploratory study. Autoantibodies presence was compared in both groups and assessed regarding to genotype, splenectomy, Gaucher disease treatment and autoimmunity-related symptoms. Twenty healthy subjects and 40 type 1 Gaucher disease patients were included. Of the studied group: 15 patients undergone splenectomy, 37 were treated either with enzyme replacement therapy (34) or with substrate reduction therapy (3), 25 were homozygous/heterozygous for the N370S mutation. In type 1 Gaucher disease group (studied group), 52% had positive autoantibodies versus 26% in control group. Antiphospholipid antibodies were more frequent in the studied group (30% vs. 5%), but without correlation to thrombosis, osteonecrosis or bone infarcts. In the studied group, antinuclear antibodies were more frequent (25% vs. 16%). None of the patients with autoantibodies had clinical manifestations of autoimmune diseases. Autoantibodies were not correlated with treatment, genotype, or splenectomy, except for anticardiolipid, more frequent in splenectomized patients. In type 1 Gaucher disease, autoantibodies were more frequent compared to a healthy population. However, they were not associated with an increased prevalence of clinical active autoimmune diseases. Copyright © 2016 Société française de rhumatologie. Published by Elsevier SAS. All rights reserved.

Efficiency of a solid-phase chemiluminescence immunoassay for detection of antinuclear and cytoplasmic autoantibodies compared with gold standard immunoprecipitation.

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Gelpí, Carmen; Pérez, Elena; Roldan, Cristina

2014-09-01

The aim of this study was to compare the degree of agreement of a novel Zenit RA chemiluminescent immunoassay (CLIA) from A. Menarini Diagnostics (Florence, Italy) and the gold standard immunoprecipitation assay to screen for the presence of specific anti-U1snRNP, anti-Sm, anti-Ro/SS-A, anti-La/SS-B, anti-Jo-1((his)tRNA-Synthetase) and anti-Scl-70(Topo I) antibodies. We studied 114 sera, 98 from patients with well-defined autoimmune connective tissue diseases and 16 from blood donor volunteers. All samples were fully characterized using the new chemiluminescent immunoassay and immunoprecipitation. In addition, all the samples were analyzed by indirect immunofluorescence (IIF) and anti-Scl-70(Topo I) antibodies were analyzed by immunoblot (IB) assay. Discrepant samples were analyzed using a commercial dot blot technique (Recomline from Mikrogen). The simple Kappa coefficient was used to measure the level of agreement between the results of Zenit RA CLIA and the gold standard. The Kappa agreement between Zenit RA CLIA and gold standard immunoprecipitation, as well as IB and IIFassays for the presence of anti-Scl-70(Topo I)(0.948) was excellent. The concordance between Zenit RA CLIA and gold standard immunoprecipitation for the presence of anti-U1snRNP (0.883), anti-Ro/SS-A (0.878), anti-Jo-1((his)tRNA-Synthetase) (0.791) and anti-Sm (0.786) was good, and excellent when the cut-off was raised to 14 U/ml (arbitrary units/ml). Between Zenit RA CLIA and gold standard immunoprecipitation for the presence of anti-La/SS-B, the Kappa agreement had a value of 0.689, but this improved to 0.775 when the cut-off was raised to14 U/ml. Precision was good based on the evaluation of replicate samples. Inter-assay coefficient variation was lower than 3.4 % (CV in %) in all the kits and <1.2 % (CV in  %) for intra-assay measurements. Our findings show that Zenit RA CLIA was specific and sensitive to detect anti-U1snRNP, anti-Sm, anti-Ro/SS-A, anti-La/SS-B, anti-Jo-1((his

Autoantibodies directed to centromere protein F in a patient with BRCA1 gene mutation

OpenAIRE

Moghaddas, Fiona; Joshua, Fredrick; Taylor, Roberta; Fritzler, Marvin J.; Toh, Ban Hock

2016-01-01

Background Autoantibodies directed to centromere protein F were first reported in 1993 and their association with malignancy has been well documented. Case We present the case of a 48-year-old Caucasian female with a BRCA1 gene mutation associated with bilateral breast cancer. Antinuclear autoantibody immunofluorescence performed for workup of possible inflammatory arthropathy showed a high titre cell cycle related nuclear speckled pattern, with subsequent confirmation by addressable laser be...

A bioluminescence resonance energy transfer 2 (BRET2) assay for monitoring seven transmembrane receptor and insulin receptor crosstalk

DEFF Research Database (Denmark)

Sanni, Samra Joke; Kulahin, Nikolaj; Jorgensen, Rasmus

2017-01-01

The angiotensin AT1 receptor is a seven transmembrane (7TM) receptor, which mediates the regulation of blood pressure. Activation of angiotensin AT1 receptor may lead to impaired insulin signaling indicating crosstalk between angiotensin AT1 receptor and insulin receptor signaling pathways....... To elucidate the molecular mechanisms behind this crosstalk, we applied the BRET2 technique to monitor the effect of angiotensin II on the interaction between Rluc8 tagged insulin receptor and GFP2 tagged insulin receptor substrates 1, 4, 5 (IRS1, IRS4, IRS5) and Src homology 2 domain-containing protein (Shc......). We demonstrate that angiotensin II reduces the interaction between insulin receptor and IRS1 and IRS4, respectively, while the interaction with Shc is unaffected, and this effect is dependent on Gαq activation. Activation of other Gαq-coupled 7TM receptors led to a similar reduction in insulin...

Studies on insulin receptor, 2. Studies on the influence of starvation and high fat diet on insulin receptor

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Sakai, Y [Hiroshima Univ. (Japan). School of Medicine

1979-08-01

The present study is to investigate an influence of starvation and high fat diet on insulin receptor of the plasma membrane by means of radioreceptor assay using /sup 125/I-labelled insulin. Male guinea pigs of Hartley strain were employed for the starvation study, and /sup 125/I-insulin binding capacity on the plasma membrane of the liver and kidney was determined at 24, 48 and 72 hours of the fast after the last meal. Male rats of Wistar strain were employed for the high fat study where the diet containing 35% of butter was fed ad libitum for 38 or 68 days. The animals were killed at the fast of 12 hours, and /sup 125/I-insulin binding capacity on the plasma membrane of the liver was determined. The results obtained are summarized as follows: 1) An increase in /sup 125/I-insulin binding capacity on the plasma membrane of the liver and kidney was observed by the starvation for 24 to 72 hours. 2) The mechanism of the increase by starvation was considered to be different by the organs; it was due to an increase in number of insulin receptor in the liver, and due to an increase in affinity of insulin receptor in the kidney. 3) In non-obese rats fed with high fat diet, the number of insulin receptor on the liver plasma membrane showed a decrease, and this observation clearly indicated that the decrease in number of the receptor did not depend on the obesity. 4) Obese rats also fed with high fat diet presented a decrease in number of insulin receptor without an elevation of insulin levels in the circulating blood. This indicated that at least in the obese rats fed with high fat diet, the decrease in number of the receptor was not due to hyperinsulinemia.

Autoantibody Profiling in Lupus Patients using Synthetic Nucleic Acids

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Klecka, Martin; Thybo, Christina; Macaubas, Claudia

2018-01-01

Autoantibodies to nuclear components of cells (antinuclear antibodies, ANA), including DNA (a-DNA), are widely used in the diagnosis and subtyping of certain autoimmune diseases, including systemic lupus erythematosus (SLE). Despite clinical use over decades, precise, reproducible measurement of a...

[Hashimoto's encephalopathy and autoantibodies].

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Yoneda, Makoto

2013-04-01

Encephalopathy occasionally occurs in association with thyroid disorders, but most of these are treatable. These encephalopathies include a neuropsychiatric disorder associated with hypothyroidism, called myxedema encephalopathy. Moreover, Hashimoto's encephalopathy (HE) has been recognized as a new clinical disease based on an autoimmune mechanism associated with Hashimoto's thyroiditis. Steroid treatment was successfully administered to these patients. Recently, we discovered that the serum autoantibodies against the NH2-terminal of α-enolase (NAE) are highly specific diagnostic biomarkers for HE. Further, we analyzed serum anti-NAE autoantibodies and the clinical features in many cases of HE from institutions throughout Japan and other countries. Approximately half of assessed HE patients carry anti-NAE antibodies. The age was widely distributed with 2 peaks (20-30 years and 50-70 years). Most HE patients were in euthyroid states, and all patients had anti-thyroid (TG) antibodies and anti-thyroid peroxidase (TPO) antibodies. Anti-TSH receptor (TSH-R) antibodies were observed in some cases. The common neuropsychiatry features are consciousness disturbance and psychosis, followed by cognitive dysfunction, involuntary movements, seizures, and ataxia. Abnormalities on electroencephalography (EEG) and decreased cerebral blood flow on brain SPECT were common findings, whereas abnormal findings on brain magnetic resonance imaging (MRI) were rare. HE patients have various clinical phenotypes such as the acute encephalopathy form, the chronic psychiatric form, and other particular clinical forms, including limbic encephalitis, progressive cerebellar ataxia, and Creutzfeldt-Jakob disease (CJD)-like form. The cerebellar ataxic form of HE clinically mimics spinocerebellar degeneration (SCD) and is characterized by the absence of nystagmus, absent or mild cerebellar atrophy, and lazy background activities on EEG. Taken together, these data suggest that the possibility of

Synthetic (+)-antroquinonol exhibits dual actions against insulin resistance by triggering AMP kinase and inhibiting dipeptidyl peptidase IV activities.

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Hsu, C Y; Sulake, R S; Huang, P-K; Shih, H-Y; Sie, H-W; Lai, Y-K; Chen, C; Weng, C F

2015-01-01

The fungal product (+)-antroquinonol activates AMP kinase (AMPK) activity in cancer cell lines. The present study was conducted to examine whether chemically synthesized (+)-antroquinonol exhibited beneficial metabolic effects in insulin-resistant states by activating AMPK and inhibiting dipeptidyl peptidase IV (DPP IV) activity. Effects of (+)-antroquinonol on DPP IV activity were measured with a DPPIV Assay Kit and effects on GLP-1-induced PKA were measured in AR42J cells. Translocation of the glucose transporter 4, GLUT4, induced either by insulin-dependent PI3K/AKT signalling or by insulin-independent AMPK activation, was assayed in differentiated myotubes. Glucose uptake and GLUT4 translocation were assayed in L6 myocytes. Mice with diet-induced obesity were used to assess effects of acute and chronic treatment with (+)-antroquinonol on glycaemic control in vivo. The results showed that of (+)-antroquinonol (100 μM ) inhibited the DPP IV activity as effectively as the clinically used inhibitor, sitagliptin. The phosphorylation of AMPK Thr(172) in differentiated myotubes was significantly increased by (+)-antroquinonol. In cells simultaneously treated with S961 (insulin receptor antagonist), insulin and (+)-antroquinonol, the combination of (+)-antroquinonol plus insulin still increased both GLUT4 translocation and glucose uptake. Further, (+)-antroquinonol and sitagliptin reduced blood glucose, when given acutely or chronically to DIO mice. Chemically synthesized (+)-antroquinonol exhibits dual effects to ameliorate insulin resistance, by increasing AMPK activity and GLUT4 translocation, along with inhibiting DPP IV activity. © 2014 The British Pharmacological Society.

Gonadal function in males with autoimmune Addison's disease and autoantibodies to steroidogenic enzymes.

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Dalla Costa, M; Bonanni, G; Masiero, S; Faggian, D; Chen, S; Furmaniak, J; Rees Smith, B; Perniola, R; Radetti, G; Garelli, S; Chiarelli, S; Albergoni, M P; Plebani, M; Betterle, C

2014-06-01

Steroidogenic enzyme autoantibodies (SEAbs) are frequently present and are markers of autoimmune premature ovarian failure (POF) in females with autoimmune Addison's disease (AAD). The prevalence and significance of SEAbs in males with AAD have not yet been defined. We studied the prevalence of SEAbs in a large cohort of males with AAD and assessed the relationship between SEAbs positivity and testicular function. A total of 154 males with AAD (mean age 34 years) were studied. SEAbs included autoantibodies to steroid-producing cells (StCA), detected by immunofluorescence, and steroid 17α-hydroxylase (17α-OHAbs) and side chain cleavage enzyme (SCCAbs) measured by immunoprecipitation assays. Gonadal function was evaluated by measuring follicle-stimulating hormone (FSH), luteinizing hormone (LH), total testosterone (TT), sex hormone-binding globulin (SHGB), anti-müllerian hormone (AMH) and inhibin-B (I-B). Twenty-six males, 10 SEAbs((+)) and 16 SEAbs((-)), were followed-up for a mean period of 7·6 years to assess the behaviour of SEAbs and testicular function. SEAbs were found in 24·7% of males with AAD, with the highest frequency in patients with autoimmune polyendocrine syndrome type 1 (APS-1). The levels of reproductive hormones in 30 SEAbs((+)) males were in the normal range according to age and were not significantly different compared to 55 SEAbs((-)) males (P > 0·05). During follow-up, both SEAbs((+)) and SEAbs((-)) patients maintained normal testicular function. SEAbs were found with high frequency in males with AAD; however, they were not associated with testicular failure. This study suggests that the diagnostic value of SEAbs in males with AAD differs compared to females, and this may be related to the immunoprivileged status of the testis. © 2014 British Society for Immunology.

Diabetes-related autoantibodies in cord blood from children of healthy mothers have disappeared by the time the child is one year old.

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Ludvigsson, Johnny; Wahlberg, Jeanette

2002-04-01

Autoantibodies found in cord blood in children who later develop diabetes might be produced by the fetus. If so, continuous autoantibody production would still be expected in these children at one year of age. We decided to determine autoantibodies in cord blood and to see whether they persisted in these children at one year. Autoantibodies against GAD65 (glutamic acid decarboxylase) and IA-2 (tyrosine phosphatase) in cord blood were determined in 2,518 randomly selected children. Forty-nine (1.95%) were positive for GAD65 antibodies, 14 (0.56%) were positive for IA-2 antibodies, and 3 of them were positive for both GAD and IA-2. Four of the mothers of children with GAD65 autoantibodies in cord blood (8.2%) had type 1 diabetes as did 5 mothers of children with IA-2 antibodies (35.7 %), but only 0.4% of the mothers had type 1 diabetes in the autoantibody-negative group (P nobody of those with positive cord blood had GAD65 or IA-2 autoantibodies. We conclude that most autoantibodies found in cord blood samples of children are probably passively transferred from mother to child. Antibody screening of cord blood cannot be used to predict diabetes in the general population. Infections during pregnancy may initiate an immune process related to diabetes development.

Comparison of the prevalence of islet autoantibodies according to age and disease duration in patients with type 1 diabetes mellitus

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Young Hwa Kong

2013-06-01

Full Text Available PurposeThis study investigated the prevalence of islet autoantibodies in children and adults with T1DM according to their age and the duration of disease.MethodsWe measured the levels of islet autoantibodies, including antiglutamic acid decarboxylase antibody (anti-GAD Ab, and combined these with anthropometric measurements and laboratory tests of 137 patients newly diagnosed with T1DM during the last 20 years. The subjects were subdivided into four groups according to their age at the onset of the disease. We then compared the prevalence of islet autoantibodies in the different age groups with the duration of disease.ResultsAmong the 137 patients, 68.9% tested positive for islet autoantibodies (71.4% within 1 year; 67.7% after 1 year of the disease onset. Within 1 year of the onset of the disease, 66.3% of the patients were positive for the anti-GAD Ab, and 35.6% were positive for IAAs. The prevalence of islet autoantibodies was significantly higher in the prepubertal groups than in the postpubertal groups (80.0% vs. 58.3%. The rate of positive islet autoantibodies changed with the duration of disease, and it differed according to the type of autoantibody and the age of the patient.ConclusionThe rates of positive islet autoantibodies were significantly higher in younger than in older patients at the time of the diagnosis of the disease. The positive rates were significantly changed 1 year after the onset of the disease in the preschool and the children groups. So these findings suggest that we need to diagnose type 1B diabetes distinguished T2DM in aldolescent group, carefully.

A rapid radioimmunoassay for insulin suitable for testing pancreatic tissue prior to transplantation

International Nuclear Information System (INIS)

Besch, W.; Kohnert, K.-D.; Hahn, H.-J.; Ziegler, M.; Lorenz, D.

1984-01-01

One way of diabetes mellitus treatment is the transplantation of insulin-producing tissue. As islet or pancreas transplantation has made progress, testing of the tissue for its vitality, insulin content and insulin secretory response prior to transplantation became necessary. Apart from problems of rejection of allografted tissue, improvement of the patients metabolic control partly depends on the insulin content of the tissue transplanted. It was the aim of the present work to establish a radioimmunoassay which ensures rapid determination of immunoreactive insulin concentrations (IRI) either intracellularly-stored or released upon stimulation of human pancreas or islet with glucose, and to demonstrate the useful application of this assay for the assessment of transplantable tissue. (Auth.)

Quantitation of autoantibodies in systemic autoimmune diseases : clinically useful?

NARCIS (Netherlands)

Kallenberg, C. G. M.; Stegeman, C. A.; Bootsma, H.; Biji, M.; Limburg, P. C.

2006-01-01

Serial assessment of levels of autoantibodies has been proposed as being clinically useful in certain systemic autoimmune diseases. In particular, attention has been given to anti-dsDNA antibodies in systemic lupus erythematosus (SLE) and ANCA in the ANCA-associated vasculitides (AAV). Much

Receptor-like protein-tyrosine phosphatase alpha specifically inhibits insulin-increased prolactin gene expression

DEFF Research Database (Denmark)

Jacob, K K; Sap, J; Stanley, F M

1998-01-01

A physiologically relevant response to insulin, stimulation of prolactin promoter activity in GH4 pituitary cells, was used as an assay to study the specificity of protein-tyrosine phosphatase function. Receptor-like protein-tyrosine phosphatase alpha (RPTPalpha) blocks the effect of insulin...... is specific by two criteria. A number of potential RPTPalpha targets were ruled out by finding (a) that they are not affected or (b) that they are not on the pathway to insulin-increased prolactin-CAT activity. The negative effect of RPTPalpha on insulin activation of the prolactin promoter is not due...... to reduced phosphorylation or kinase activity of the insulin receptor or to reduced phosphorylation of insulin receptor substrate-1 or Shc. Inhibitor studies suggest that insulin-increased prolactin gene expression is mediated by a Ras-like GTPase but is not mitogen-activated protein kinase dependent...

Folinic acid treatment for schizophrenia associated with folate receptor autoantibodies.

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Ramaekers, V T; Thöny, B; Sequeira, J M; Ansseau, M; Philippe, P; Boemer, F; Bours, V; Quadros, E V

2014-12-01

Auto-antibodies against folate receptor alpha (FRα) at the choroid plexus that block N(5)-methyltetrahydrofolate (MTHF) transfer to the brain were identified in catatonic schizophrenia. Acoustic hallucinations disappeared following folinic acid treatment. Folate transport to the CNS prevents homocysteine accumulation and delivers one-carbon units for methyl-transfer reactions and synthesis of purines. The guanosine derivative tetrahydrobiopterin acts as common co-factor for the enzymes producing dopamine, serotonin and nitric oxide. Our study selected patients with schizophrenia unresponsive to conventional treatment. Serum from these patients with normal plasma homocysteine, folate and vitamin B12 was tested for FR autoantibodies of the blocking type on serial samples each week. Spinal fluid was analyzed for MTHF and the metabolites of pterins, dopamine and serotonin. The clinical response to folinic acid treatment was evaluated. Fifteen of 18 patients (83.3%) had positive serum FR auto-antibodies compared to only 1 in 30 controls (3.3%) (χ(2)=21.6; pfolate flux to the CNS, which explained low CSF folate values in 6 and normal values in 7 patients. The mean±SD for CSF MTHF was diminished compared to previously established controls (t-test: 3.90; p=0.0002). A positive linear correlation existed between CSF MTHF and biopterin levels. CSF dopamine and serotonin metabolites were low or in the lower normal range. Administration of folinic acid (0.3-1mg/kg/day) to 7 participating patients during at least six months resulted in clinical improvement. Assessment of FR auto-antibodies in serum is recommended for schizophrenic patients. Clinical negative or positive symptoms are speculated to be influenced by the level and evolution of FRα antibody titers which determine folate flux to the brain with up- or down-regulation of brain folate intermediates linked to metabolic processes affecting homocysteine levels, synthesis of tetrahydrobiopterin and neurotransmitters

Prenatal Exposure to Autism-Specific Maternal Autoantibodies Alters Proliferation of Cortical Neural Precursor Cells, Enlarges Brain, and Increases Neuronal Size in Adult Animals.

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Martínez-Cerdeño, Verónica; Camacho, Jasmin; Fox, Elizabeth; Miller, Elaine; Ariza, Jeanelle; Kienzle, Devon; Plank, Kaela; Noctor, Stephen C; Van de Water, Judy

2016-01-01

Autism spectrum disorders (ASDs) affect up to 1 in 68 children. Autism-specific autoantibodies directed against fetal brain proteins have been found exclusively in a subpopulation of mothers whose children were diagnosed with ASD or maternal autoantibody-related autism. We tested the impact of autoantibodies on brain development in mice by transferring human antigen-specific IgG directly into the cerebral ventricles of embryonic mice during cortical neurogenesis. We show that autoantibodies recognize radial glial cells during development. We also show that prenatal exposure to autism-specific maternal autoantibodies increased stem cell proliferation in the subventricular zone (SVZ) of the embryonic neocortex, increased adult brain size and weight, and increased the size of adult cortical neurons. We propose that prenatal exposure to autism-specific maternal autoantibodies directly affects radial glial cell development and presents a viable pathologic mechanism for the maternal autoantibody-related prenatal ASD risk factor. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Serum Autoantibody Measurement for the Detection of Hepatocellular Carcinoma

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Middleton, Catrin H.; Irving, William; Robertson, John F. R.; Murray, Andrea; Parsy-Kowalska, Celine B.; Macdonald, Isabel K.; McElveen, Jane; Allen, Jared; Healey, Graham F.; Thomson, Brian J.; Ryder, Stephen J.; Holdenrieder, Stefan; Chapman, Caroline J.

2014-01-01

Background Individuals with liver disease, and especially those with Hepatitis B or C, are at an increased risk of developing hepatocellular carcinoma (HCC) which is the third most common cause of cancer-related death worldwide. Inadequate screening tests largely account for presentation of advanced tumours and high mortality rates. Early detection of HCC amongst high-risk groups is paramount in improving prognosis. This research aimed to further characterise the previously described humoral immune response raised to tumour-associated antigens (TAAs) in the serum of patients with HCC. Methods Serum from 96 patients with confirmed HCC, 96 healthy controls matched for age and sex, 78 patients with confirmed liver cirrhosis and 91 patients with confirmed chronic liver disease were analysed for the presence of IgG autoantibodies raised to 41 recombinant TAAs/antigen fragments by ELISA. Results Varying autoantibody specificities (97–100%) and sensitivities (0–10%) were observed to individual TAAs. A 21-antigen panel achieved a specificity of 92% and sensitivity of 45% for the detection of HCC. This same panel identified 21% of 169 high-risk controls as having elevated autoantibody levels. A reproducible panel of 10 antigens achieved a specificity of 91% and sensitivity of 41% in HCC. 15% of 152 high-risk controls gave positive results with this panel. Conclusions This minimally invasive blood test has the potential to offer advantages over currently available tools for the identification of HCC amongst pre-disposed patients. Results are comparable to current gold standards in HCC (Ultrasonography) and to similar tests in other cancers (EarlyCDT-Lung). PMID:25093332

Serum autoantibody measurement for the detection of hepatocellular carcinoma.

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Catrin H Middleton

Full Text Available BACKGROUND: Individuals with liver disease, and especially those with Hepatitis B or C, are at an increased risk of developing hepatocellular carcinoma (HCC which is the third most common cause of cancer-related death worldwide. Inadequate screening tests largely account for presentation of advanced tumours and high mortality rates. Early detection of HCC amongst high-risk groups is paramount in improving prognosis. This research aimed to further characterise the previously described humoral immune response raised to tumour-associated antigens (TAAs in the serum of patients with HCC. METHODS: Serum from 96 patients with confirmed HCC, 96 healthy controls matched for age and sex, 78 patients with confirmed liver cirrhosis and 91 patients with confirmed chronic liver disease were analysed for the presence of IgG autoantibodies raised to 41 recombinant TAAs/antigen fragments by ELISA. RESULTS: Varying autoantibody specificities (97-100% and sensitivities (0-10% were observed to individual TAAs. A 21-antigen panel achieved a specificity of 92% and sensitivity of 45% for the detection of HCC. This same panel identified 21% of 169 high-risk controls as having elevated autoantibody levels. A reproducible panel of 10 antigens achieved a specificity of 91% and sensitivity of 41% in HCC. 15% of 152 high-risk controls gave positive results with this panel. CONCLUSIONS: This minimally invasive blood test has the potential to offer advantages over currently available tools for the identification of HCC amongst pre-disposed patients. Results are comparable to current gold standards in HCC (Ultrasonography and to similar tests in other cancers (EarlyCDT-Lung.

Clinical utility of autoantibodies and biologic markers in rheumatoid ...

African Journals Online (AJOL)

Objective: To review the current and emerging auto-antibodies and biologic markers in rheumatoid arthritis. Data source: Published original research work and reviews were searched in English related to pathophysiology, diagnosis and auto antibodies in rheumatoid arthritis. Study design: Only articles that emphasis on ...

Increased prevalence of autoimmune disorders and autoantibodies in parents of children with opsoclonus-myoclonus syndrome (OMS).

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Krasenbrink, I; Fühlhuber, V; Juhasz-Boess, I; Stolz, E; Hahn, A; Kaps, M; Hero, B; Blaes, F

2007-06-01

Opsoclonus-myoclonus syndrome (OMS) is a rare neurological disease in childhood which can be associated with neuroblastoma. Since autoantibodies have been detected in some patients with OMS, an autoimmune etiology is suspected. We compared the prevalence of autoimmune disorders and autoantibodies in parents of children with OMS and in a group of controls of same age and sex. Autoimmune diseases were found in 15.8% of the parents of OMS children, but only in 2.0% of the controls (pOMS parents (42.8% vs. 8.0%, pOMS parents also had significantly more autoantibodies against CNS structures than the controls (pOMS and may also hint to a genetic susceptibility for OMS.

Fibroblast growth factor 21 improves insulin sensitivity and synergizes with insulin in human adipose stem cell-derived (hASC adipocytes.

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Darwin V Lee

Full Text Available Fibroblast growth factor 21 (FGF21 has evolved as a major metabolic regulator, the pharmacological administration of which causes weight loss, insulin sensitivity and glucose control in rodents and humans. To understand the molecular mechanisms by which FGF21 exerts its metabolic effects, we developed a human in vitro model of adipocytes to examine crosstalk between FGF21 and insulin signaling. Human adipose stem cell-derived (hASC adipocytes were acutely treated with FGF21 alone, insulin alone, or in combination. Insulin signaling under these conditions was assessed by measuring tyrosine phosphorylation of insulin receptor (InsR, insulin receptor substrate-1 (IRS-1, and serine 473 phosphorylation of Akt, followed by a functional assay using 14C-2-deoxyglucose [14C]-2DG to measure glucose uptake in these cells. FGF21 alone caused a modest increase of glucose uptake, but treatment with FGF21 in combination with insulin had a synergistic effect on glucose uptake in these cells. The presence of FGF21 also effectively lowered the insulin concentration required to achieve the same level of glucose uptake compared to the absence of FGF21 by 10-fold. This acute effect of FGF21 on insulin signaling was not due to IR, IGF-1R, or IRS-1 activation. Moreover, we observed a substantial increase in basal S473-Akt phosphorylation by FGF21 alone, in contrast to the minimal shift in basal glucose uptake. Taken together, our data demonstrate that acute co-treatment of hASC-adipocytes with FGF21 and insulin can result in a synergistic improvement in glucose uptake. These effects were shown to occur at or downstream of Akt, or separate from the canonical insulin signaling pathway.

Fully convergent chemical synthesis of ester insulin: determination of the high resolution X-ray structure by racemic protein crystallography.

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Avital-Shmilovici, Michal; Mandal, Kalyaneswar; Gates, Zachary P; Phillips, Nelson B; Weiss, Michael A; Kent, Stephen B H

2013-02-27

Efficient total synthesis of insulin is important to enable the application of medicinal chemistry to the optimization of the properties of this important protein molecule. Recently we described "ester insulin"--a novel form of insulin in which the function of the 35 residue C-peptide of proinsulin is replaced by a single covalent bond--as a key intermediate for the efficient total synthesis of insulin. Here we describe a fully convergent synthetic route to the ester insulin molecule from three unprotected peptide segments of approximately equal size. The synthetic ester insulin polypeptide chain folded much more rapidly than proinsulin, and at physiological pH. Both the D-protein and L-protein enantiomers of monomeric DKP ester insulin (i.e., [Asp(B10), Lys(B28), Pro(B29)]ester insulin) were prepared by total chemical synthesis. The atomic structure of the synthetic ester insulin molecule was determined by racemic protein X-ray crystallography to a resolution of 1.6 Å. Diffraction quality crystals were readily obtained from the racemic mixture of {D-DKP ester insulin + L-DKP ester insulin}, whereas crystals were not obtained from the L-ester insulin alone even after extensive trials. Both the D-protein and L-protein enantiomers of monomeric DKP ester insulin were assayed for receptor binding and in diabetic rats, before and after conversion by saponification to the corresponding DKP insulin enantiomers. L-DKP ester insulin bound weakly to the insulin receptor, while synthetic L-DKP insulin derived from the L-DKP ester insulin intermediate was fully active in binding to the insulin receptor. The D- and L-DKP ester insulins and D-DKP insulin were inactive in lowering blood glucose in diabetic rats, while synthetic L-DKP insulin was fully active in this biological assay. The structural basis of the lack of biological activity of ester insulin is discussed.

In vitro and in vivo potency of insulin analogues designed for clinical use.

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Vølund, A; Brange, J; Drejer, K; Jensen, I; Markussen, J; Ribel, U; Sørensen, A R; Schlichtkrull, J

1991-11-01

Analogues of human insulin designed to have improved absorption properties after subcutaneous injection have been prepared by recombinant DNA technology. Five rapidly absorbed analogues, being predominantly in mono- or di-meric states in the pharmaceutical preparation, and a hexameric analogue with very low solubility at neutral pH and slow absorption, were studied. Receptor binding assays with HEP-G2 cells showed overall agreement with mouse free adipocyte assays. Two analogues, B28Asp and A21Gly + B27Arg + B30Thr-NH2, had nearly the same molar in vitro potency as human insulin. Another two showed increased adipocyte potency and receptor binding, B10Asp 194% and 333% and A8His + B4His + B10Glu + B27His 575% and 511%, while B9Asp + B27Glu showed 29% and 18% and the B25Asp analogue only 0.12% and 0.05% potency. Bioassays in mice or rabbits of the analogues except B25Asp showed that they had the same in vivo potency as human insulin 1.00 IU = 6.00 nmol. Thus the variation had the same in vivo potency as human insulin 1.00 IU = 6.00 nmol. Thus the variation in in vivo potency reflects the differences in receptor binding affinity. Relative to human insulin a low concentration is sufficient for a high affinity analogue to produce a given receptor complex formation and metabolic response. In conclusion, human insulin and analogues with markedly different in vitro potencies were equipotent in terms of hypoglycaemic effect. This is in agreement with the concept that elimination of insulin from blood and its subsequent degradation is mediated by insulin receptors.

Antiphospholipase A2 Receptor Autoantibodies: A Comparison of Three Different Immunoassays for the Diagnosis of Idiopathic Membranous Nephropathy

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Astrid Behnert

2014-01-01

Full Text Available Background. The recent identification of circulating autoantibodies directed towards the M-type phospholipase A2 receptor (PLA2R has been a major advancement in the serological diagnosis of idiopathic membranous nephropathy (IMN, a common cause of nephrotic syndrome in adults. The goal of this study was to compare the performance characteristics of two commercial assays as well as the first addressable laser bead immunoassay (ALBIA developed for the detection of anti-PLA2R antibodies. Methods. Serum samples of 157 IMN patients and 142 controls were studied. Samples were tested by a cell based immunofluorescence assay (CBA-IFA, Euroimmun, Germany, by ELISA (Euroimmun, and by a novel ALBIA employing an in vivo expressed recombinant human PLA2R. Results. Overall, the three assays showed significant qualitative and quantitative correlation. As revealed by receiver operating characteristic analysis, the ALBIA correlated better with the CBA-IFA than the ELISA (P=0.0003. The clinical sensitivities/specificities for IMN were 60.0% (51.0–68.5%/98.6% (95.0–99.8% and 56.2% (47.2–64.8%/100.0% (97.4–100.0% for ALBIA and CBA-IFA, respectively. Conclusion. The ALBIA represents a promising assay for the detection of anti-PLA2R antibodies showing similar performance to the CBA-IFA and the advantage of ease of use and suitability for high throughput, rapid turnaround times, and multiplexing.

Paraneoplastic antigen Ma2 autoantibodies as specific blood biomarkers for detection of early recurrence of small intestine neuroendocrine tumors.

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Tao Cui

Full Text Available BACKGROUND: Small intestine neuroendocrine tumors (SI-NETs belong to a rare group of cancers. Most patients have developed metastatic disease at the time of diagnosis, for which there is currently no cure. The delay in diagnosis is a major issue in the clinical management of the patients and new markers are urgently needed. We have previously identified paraneoplastic antigen Ma2 (PNMA2 as a novel SI-NET tissue biomarker. Therefore, we evaluated whether Ma2 autoantibodies detection in the blood stream is useful for the clinical diagnosis and recurrence of SI-NETs. METHODOLOGY/PRINCIPAL FINDINGS: A novel indirect ELISA was set up to detect Ma2 autoantibodies in blood samples of patients with SI-NET at different stages of disease. The analysis was extended to include typical and atypical lung carcinoids (TLC and ALC, to evaluate whether Ma2 autoantibodies in the blood stream become a general biomarker for NETs. In total, 124 blood samples of SI-NET patients at different stages of disease were included in the study. The novel Ma2 autoantibody ELISA showed high sensitivity, specificity and accuracy with ROC curve analysis underlying an area between 0.734 and 0.816. Ma2 autoantibodies in the blood from SI-NET patients were verified by western blot and sequential immunoprecipitation. Serum antibodies of patients stain Ma2 in the tumor tissue and neurons. We observed that SI-NET patients expressing Ma2 autoantibody levels below the cutoff had a longer progression and recurrence-free survival compared to those with higher titer. We also detected higher levels of Ma2 autoantibodies in blood samples from TLC and ALC patients than from healthy controls, as previously shown in small cell lung carcinoma samples. CONCLUSION: Here we show that high Ma2 autoantibody titer in the blood of SI-NET patients is a sensitive and specific biomarker, superior to chromogranin A (CgA for the risk of recurrence after radical operation of these tumors.

Paraneoplastic antigen Ma2 autoantibodies as specific blood biomarkers for detection of early recurrence of small intestine neuroendocrine tumors.

Science.gov (United States)

Cui, Tao; Hurtig, Monica; Elgue, Graciela; Li, Su-Chen; Veronesi, Giulia; Essaghir, Ahmed; Demoulin, Jean-Baptiste; Pelosi, Giuseppe; Alimohammadi, Mohammad; Öberg, Kjell; Giandomenico, Valeria

2010-12-30

Small intestine neuroendocrine tumors (SI-NETs) belong to a rare group of cancers. Most patients have developed metastatic disease at the time of diagnosis, for which there is currently no cure. The delay in diagnosis is a major issue in the clinical management of the patients and new markers are urgently needed. We have previously identified paraneoplastic antigen Ma2 (PNMA2) as a novel SI-NET tissue biomarker. Therefore, we evaluated whether Ma2 autoantibodies detection in the blood stream is useful for the clinical diagnosis and recurrence of SI-NETs. A novel indirect ELISA was set up to detect Ma2 autoantibodies in blood samples of patients with SI-NET at different stages of disease. The analysis was extended to include typical and atypical lung carcinoids (TLC and ALC), to evaluate whether Ma2 autoantibodies in the blood stream become a general biomarker for NETs. In total, 124 blood samples of SI-NET patients at different stages of disease were included in the study. The novel Ma2 autoantibody ELISA showed high sensitivity, specificity and accuracy with ROC curve analysis underlying an area between 0.734 and 0.816. Ma2 autoantibodies in the blood from SI-NET patients were verified by western blot and sequential immunoprecipitation. Serum antibodies of patients stain Ma2 in the tumor tissue and neurons. We observed that SI-NET patients expressing Ma2 autoantibody levels below the cutoff had a longer progression and recurrence-free survival compared to those with higher titer. We also detected higher levels of Ma2 autoantibodies in blood samples from TLC and ALC patients than from healthy controls, as previously shown in small cell lung carcinoma samples. Here we show that high Ma2 autoantibody titer in the blood of SI-NET patients is a sensitive and specific biomarker, superior to chromogranin A (CgA) for the risk of recurrence after radical operation of these tumors.

[Efficacy of combination therapy with pegylated-interferon alfa-2a plus ribavirin in autoantibody-positive chronic hepatitis C patients].

Science.gov (United States)

Li, Ya-xin; Yang, Yan-jia; Yang, Mei; Chen, Li-yu; Lu, Jia-jie; Ma, Yuan-ji; Liu, Kai; Lei, Xue-zhong; Tang, Hong

2013-05-01

To evaluate the therapeutic efficacy of antiviral combination therapy with pegylated-interferon alpha-2a plus ribavirin (RBV) in patients with autoantibody-positive chronic hepatitis C (CHC) and to investigate the impact of the presence of autoantibodies on the treatment outcome. Eighty-six consecutive CHC patients who underwent a 48-week treatment regimen composed of Peg-IFNa-2a (135 or 180 mug/wk) plus weight-based RBV ( less than or equal to 65 kg, 800 mg/d; 65 to 75 kg, 1000 mg/d; more than or equal to75 kg, 1200 mg/d ). Prior to treatment (baseline) and at end of treatment (EOT; week 48), levels of antinuclear antibody (ANA), anti-smooth muscle antibody (SMA), anti liver/kidney microsomal antibody type 1 (LKM1), anti-La (SSB), and anti liver cytosolic-1 (LC-1) were detected by indirect immunofluorescence. At baseline, during treatment (weeks 4, 12, 24, and 36), EOT, and 24 weeks after EOT, levels of HCV RNA were assessed by real-time quantitative PCR. Rapid virological response (RVR) was defined as HCV RNA less than 10(3) copy/ml at week 4. Sustained virologic response (SVR) was defined as HCV RNA load below the lower limit of detection at 24 weeks after EOT. Correlation between autoantibodies and treatment-induced reduced HCV RNA load was assessed by univariate analysis of variance or chi-squared tests. Autoantibodies were detected in 24 patients, which included 14 ANA-positive patients, five SMA-positive patients, three LKM1-positive patients, one patient with double-positivity for ANA and SSB, and one patient with double-positivity for ANA and LC-1. The autoantibody-positive patients and autoantibody-negative patients showed similar rates of RVR (70.8% vs. 72.5%, P more than 0.05) and SVR (81.4% vs. 82.2%, P more than 0.05). Antiviral therapy with Peg-IFNa-2a RBV can effectively reduce the HCV RNA load in autoantibody-positive CHC patients; however, the presence of autoantibodies may not be an independent predictor of therapy outcome.

Paving the way to understand humoral autoantibody epilepsy on the molecular level

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Guiscard eSeebohm

2015-07-01

Full Text Available Correct function of neuronal networks is enabled by a delicate interplay among neurons communicating with each other. One of the keys is the communication at chemical synapses where neurotransmitters like glutamate, GABA and glycine enable signal transfer over the synaptic cleft. Thereby, the neurotransmitters are released from the presynapse and bind as ligands to specific receptors at the postsynaptic side to allow for modulation of the postsynaptic membrane potentials. The postsynaptic electrical signal, which is highly modulated by voltage gated ion channels, spreads over the dendritic tree and is thus integrated to allow for generation of action potentials at the axon hillock. This concert of receptors and voltage gated ion channels depends on correct function of all its components. Misfunction of receptors and/or voltage-gated potassium channels (VGKC leads to diverse adverse effects in patients. Such malfunctions can be the result of inherited genetic alterations or pharmacological side effects by drugs. Recently, auto-antibodies targeting receptor or channel complexes like NMDAR, AMPAR, GABA-receptors, glycine-receptors, LGI1 or CASPR2 (previously termed VGKC-complex antibodies have been discovered. The presence of specific auto-antibodies against these targets associates with severe forms of antibody-mediated encephalitis. Understanding the molecular details of auto-antibody actions on receptor and VGKC complexes is highly desirable and may open the path to develop specific therapies to treat humoral autoimmune encephalitis. Here, we summarize the current knowledge and discuss technical approaches to fill the gap of knowledge. These techniques include electrophysiology, biochemical approaches for epitope mapping and in silico modeling to simulate molecular interactions between autoantibody and its molecular target.

Life-threatening bleeding in a case of autoantibody-induced factor VII deficiency.

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Okajima, K; Ishii, M

1999-02-01

A male patient presented with life-threatening bleeding induced by autoantibody-induced factor VII (F.VII) deficiency. This patient had macroscopic hematuria, skin ecchymosis, gastrointestinal bleeding, and a neck hematoma that was causing disturbed respiration. He developed acute renal failure and acute hepatic failure, probably due to obstruction of the ureters and the biliary tract, respectively. Although activated partial thromboplastin time was normal, prothrombin time (PT) was remarkably prolonged at 71.8 seconds compared to 14.0 seconds in a normal control. Both the immunoreactive level of F.VII antigen and the F.VII activity of the patient's plasma samples were VII activity. These findings suggested the presence of a plasma inhibitor for F.VII. After administration of large doses of methylprednisolone, PT was gradually shortened and plasma levels of F.VII increased over time. Bleeding, acute renal failure, and acute hepatic failure improved markedly following the steroid treatment. These observations suggest that life-threatening bleeding can be induced by autoantibody-induced F.VII deficiency and that immunosuppressive therapy using large doses of steroid can be successful in inhibiting the production of the autoantibody.

Studies of Filipino patients with systemic lupus erythematosus: autoantibody profile of first-degree relatives.

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Navarra, S V; Ishimori, M I; Uy, E A; Hamijoyo, L; Sama, J; James, J A; Holers, V M; Weisman, M H

2011-04-01

This study surveyed the frequency of autoantibodies among un-affected first-degree relatives (FDRs) of Filipino systemic lupus erythematosus (SLE) patients compared with healthy un-related Filipino controls. The sensitivity, specificity and predictive value of the autoantibodies for SLE diagnosis were also assessed in this Filipino cohort. Filipino patients included in the University of Santo Tomas (UST) Lupus Database and un-affected FDRs were recruited. Healthy controls included those with no known personal or family history of autoimmune disease. The following autoantibodies were tested in all subjects: anti-nuclear antibody (ANA), anti-dsDNA, anti-Ro/SSA, anti-chromatin, anti-thyroid microsome, and anti-cardiolipin antibodies. Participants included 232 SLE patients, 546 FDRs, and 221 healthy controls. Median age of patients was 27 (range 8-66) years with median disease duration of 27.5 (range 1-292) months. Median age of FDRs was 42.0 (range 5-87) years. Compared with healthy controls, there were significantly more FDRs with positive ANA at titers 1 : 40 to 1 : 160 (p Filipinos, with a significant proportion of un-affected FDRs of SLE patients testing positive for autoantibodies compared with healthy Filipino controls. A longitudinal observational study in this same cohort will determine which proportion of these un-affected FDRs will evolve into clinical SLE disease in the future.

Autoantibodies in renal diseases – clinical significance and recent developments in serological detection

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Gianna eKirsztajn

2015-05-01

Full Text Available Autoimmune dysfunctions are the bête noire in a range of debilitating nephropathies. Autoimmune-mediated damage to the kidneys can be triggered by autoantibodies directed against specific proteins or renal structures, for example the phospholipase A2 receptor or the glomerular basement membrane, resulting in glomerular diseases such as primary membranous nephropathy or Goodpasture’s disease. Moreover, secondary damage to the kidney can be part of the wide-reaching effects of systemic autoimmune diseases such as vasculitis or systemic lupus erythematosus (SLE – the latter counts lupus nephritis among its most severe manifestations. Systemic autoimmune diseases are characterized by non-organ-specific autoantibodies, directed for example against neutrophil cytoplasmic antigens in systemic vasculitis and against double-stranded DNA and nucleosomes in SLE.A large variety of innovative and highly specific and sensitive autoantibody tests have been developed in the last years that are available to identify autoimmune kidney diseases at an early stage. Thus, serological in vitro diagnostics allow for appropriate interventional therapy in order to prevent disease progression often resulting in need of dialysis and transplantation.

4PS/insulin receptor substrate (IRS)-2 is the alternative substrate of the insulin receptor in IRS-1-deficient mice.

Science.gov (United States)

Patti, M E; Sun, X J; Bruening, J C; Araki, E; Lipes, M A; White, M F; Kahn, C R

1995-10-20

Insulin receptor substrate-1 (IRS-1) is the major cytoplasmic substrate of the insulin and insulin-like growth factor (IGF)-1 receptors. Transgenic mice lacking IRS-1 are resistant to insulin and IGF-1, but exhibit significant residual insulin action which corresponds to the presence of an alternative high molecular weight substrate in liver and muscle. Recently, Sun et al. (Sun, X.-J., Wang, L.-M., Zhang, Y., Yenush, L. P., Myers, M. G., Jr., Glasheen, E., Lane, W.S., Pierce, J. H., and White, M. F. (1995) Nature 377, 173-177) purified and cloned 4PS, the major substrate of the IL-4 receptor-associated tyrosine kinase in myeloid cells, which has significant structural similarity to IRS-1. To determine if 4PS is the alternative substrate of the insulin receptor in IRS-1-deficient mice, we performed immunoprecipitation, immunoblotting, and phosphatidylinositol (PI) 3-kinase assays using specific antibodies to 4PS. Following insulin stimulation, 4PS is rapidly phosphorylated in liver and muscle, binds to the p85 subunit of PI 3-kinase, and activates the enzyme. Insulin stimulation also results in the association of 4PS with Grb 2 in both liver and muscle. In IRS-1-deficient mice, both the phosphorylation of 4PS and associated PI 3-kinase activity are enhanced, without an increase in protein expression. Immunodepletion of 4PS from liver and muscle homogenates removes most of the phosphotyrosine-associated PI 3-kinase activity in IRS-1-deficient mice. Thus, 4PS is the primary alternative substrate, i.e. IRS-2, which plays a major role in physiologic insulin signal transduction via both PI 3-kinase activation and Grb 2/Sos association. In IRS-1-deficient mice, 4PS/IRS-2 provides signal transduction to these two major pathways of insulin signaling.

Effects of the thymic microenvironment on autoantibody production in (NZB X NZW)F1 mice

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Huston, D.P.; Smathers, P.A.; Reeves, J.P.; Steinberg, A.D.

1983-01-01

The effects of the thymic microenvironment on autoantibody production in (NZB X NZW)F1 mice were studied. Neonatally thymectomized male and female F1 mice reconstituted with a parental or F1-irradiated thymic lobe were compared to nonreconstituted and sham-thymectomized controls. While maleness retarded the spontaneous production of ss- and ds-DNA antibodies, thymic grafts did not suppress antibodies to ss-DNA in either sex, but did suppress the production of antibodies to ds-DNA in female mice. A unique property of NZB thymic grafts was the inability to suppress anti-RBC antibodies in male mice. Thus, (i) the gender of the F1 recipient was the most important determinant of production of antibodies to ss-DNA, (ii) either maleness or the thymic microenvironment could retard production of anti-ds-DNA antibodies, and (iii) both gender and the thymic microenvironment were important in the regulation of anti-RBC antibody production. Since the administration of thymosin did not suppress autoantibody production, the effects of the thymic grafts was not solely via thymic hormone production. These studies suggest that sex hormones and/or the thymic microenvironment can exert a suppressive effect on autoantibody production and that autoantibodies differ in their susceptibility to such suppression

Insulin stimulates choline acetyltransferase activity in cultured embryonic chicken retina neurons

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Kyriakis, J.M.; Hausman, R.E.; Peterson, S.W.

1987-01-01

The effect of insulin on the appearance of the enzyme choline acetyltransferase in embryonic chicken retina neurons cultured in defined medium was studied. In the presence of a minimal level of insulin (1 ng/ml), ChoAcT activity increased with time in culture. A correspondence between the insulin concentration in the defined medium (1-100 ng/ml) and both the rate of increase and maximum attained level of ChoAcT activity was observed. Maximal ChoAcT activity was 2- to 3-fold greater in cells cultured in the presence of 100 ng of insulin per ml than in cells cultured in the presence of 1 ng of insulin per ml. To elicit maximum ChoAcT activity, insulin at 100 ng/ml was required in the medium for only the first 4 days of the culture period, at which time insulin could be reduced to maintenance levels (10 ng/ml) without affecting ChoAcT activity. Insulin binding assays performed during a 7-day culture period revealed that irrespective of the 125 I-insulin concentration in the medium during culture, cell-surface insulin receptors decreased by ≅ 90% between 4 and 7 days in culture. This decrease in insulin binding corresponded to the observed decrease in the sensitivity of ChoAcT activity to insulin. The findings suggest that insulin plays a role in mediating cholinergic differentiation in the embryonic chicken retina

Serological analysis of human IgG and IgE anti-insulin antibodies by solid-phase radioimmunoassays

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Hamilton, R.G.; Rendell, M.; Adkinson, N.F. Jr.

1980-01-01

A single solid-phase assay system which is useful for quantitative measurement of both IgG and IgE anti-insulin antibodies in human serum has been developed. Insulin-specific immunoglobulins are absorbed from human serum by excess quantities of insulin-agarose. After washes to remove unbound immunoglobulins, radioiodinated Staph A or rabbit anti-human IgE is added to detect bound IgG or IgE anbitodies, respectively

Label-free nanoplasmonic sensing of tumor-associate autoantibodies for early diagnosis of colorectal cancer.

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Soler, Maria; Estevez, M-Carmen; Villar-Vazquez, Roi; Casal, J Ignacio; Lechuga, Laura M

2016-08-03

Colorectal cancer is treatable and curable when detected at early stages. However there is a lack of less invasive and more specific screening and diagnosis methods which would facilitate its prompt identification. Blood circulating autoantibodies which are immediately produced by the immune system at tumor appearance have become valuable biomarkers for preclinical diagnosis of cancer. In this work, we present the rapid and label-free detection of colorectal cancer autoantibodies directly in blood serum or plasma using a recently developed nanoplasmonic biosensor. Our nanoplasmonic device offers sensitive and real-time quantification of autoantibodies with excellent selectivity and reproducibility, achieving limits of detection around 1 nM (150-160 ng mL(-1)). A preliminary evaluation of clinical samples of colorectal cancer patients has shown good correlation with ELISA. These results demonstrate the reliability of the nanobiosensor strategy and pave the way towards the achievement of a sensitive diagnostic tool for early detection of colorectal cancer. Copyright © 2016 Elsevier B.V. All rights reserved.

Thyroid Autoantibodies in the Cerebrospinal Fluid of Subjects with and without Thyroid Disease: Implications for Hashimoto’s Encephalopathy

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Ioannis Ilias

2015-01-01

Full Text Available Introduction. Plasma antithyroid peroxidase (anti-TPO and anti-thyroglobulin antibodies (anti-Tg are widely used in the diagnosis of autoimmune thyroiditis. No research has compared anti-TPO and anti-Tg both in plasma and cerebrospinal fluid (CSF of healthy individuals vis-à-vis patients with thyroid disease. Methods. We measured anti-TPO and anti-Tg antibodies in plasma and CSF in nine subjects (mean age ± SD: 73 ± 6 years with hypothyroidism and nine subjects (mean age ± SD: 73 ± 8 years without thyroid disease. Results. The concentration of anti-TPO autoantibodies in CSF was very low compared to plasma in both subjects with thyroid and without thyroid disease (P=0.007. CSF anti-Tg autoantibodies titers were very low compared to the plasma in subjects with thyroid disease (P=0.004, whereas, in subjects without thyroid disease, this difference did not reach statistical significance (P=0.063. Conclusions. Thyroid autoantibodies levels were low in plasma and CSF; we did not observe any transfer of thyroid autoantibodies from the peripheral blood to the CSF. Therefore, regarding Hashimoto’s encephalopathy, where elevated antithyroid autoantibodies are often measured in blood, it is more likely that thyroiditis and encephalopathy represent nonspecific, but distinct, events of an aggressive immune system.

Dissecting the role of disulfide bonds on the amyloid formation of insulin

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Li, Yang; Gong, Hao; Sun, Yue; Yan, Juan; Cheng, Biao; Zhang, Xin; Huang, Jing; Yu, Mengying; Guo, Yu; Zheng, Ling; Huang, Kun

2012-01-01

Highlights: ► We dissect how individual disulfide bond affects the amyloidogenicity of insulin. ► A controlled reduction system for insulin is established in this study. ► Disulfide breakage is associated with unfolding and increased amyloidogenicity. ► Breakage of A6-A11 is associated with significantly increased cytotoxicity. ► Analogs without A6-A11 have a higher potency to form high order toxic oligomers. -- Abstract: Disulfide bonds play a critical role in the stability and folding of proteins. Here, we used insulin as a model system, to investigate the role of its individual disulfide bond during the amyloid formation of insulin. Tris(2-carboxyethyl)phosphine (TCEP) was applied to reduce two of the three disulfide bonds in porcine insulin and the reduced disulfide bonds were then alkylated by iodoacetamide. Three disulfide bond-modified insulin analogs, INS-2 (lack of A6-A11), INS-3 (lack of A7-B7) and INS-6 (lack of both A6-A11 and A7-B7), were obtained. Far-UV circular dichroism (CD) spectroscopy results indicated that the secondary structure of INS-2 was the closest to insulin under neutral conditions, followed by INS-3 and INS-6, whereas in an acidic solution all analogs were essentially unfolded. To test how these modifications affect the amyloidogenicity of insulin, thioflavin-T (ThT) fluorescence and transmission electronic microscopy (TEM) were performed. Our results showed that all analogs were more prone to aggregation than insulin, with the order of aggregation rates being INS-6 > INS-3 > INS-2. Cross-linking of unmodified proteins (PICUP) assay results showed that analogs without A6-A11 (INS-2 and INS-6) have a higher potential for oligomerization than insulin and INS-3, which is accompanied with a higher cytotoxicity as the hemolytic assays of human erythrocytes suggested. The results indicated that breakage of A7-B7 induced more unfolding of the insulin structure and a higher amyloidogenicity than breakage of A6-A11, but breakage of A6

Autoantibody profiling on human proteome microarray for biomarker discovery in cerebrospinal fluid and sera of neuropsychiatric lupus.

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Chaojun Hu

Full Text Available Autoantibodies in cerebrospinal fluid (CSF from patients with neuropsychiatric systemic lupus erythematosus (NPSLE may be potential biomarkers for prediction, diagnosis, or prognosis of NPSLE. We used a human proteome microarray with~17,000 unique full-length human proteins to investigate autoantibodies associated with NPSLE. Twenty-nine CSF specimens from 12 NPSLE, 7 non-NPSLE, and 10 control (non-systemic lupus erythematosuspatients were screened for NPSLE-associated autoantibodies with proteome microarrays. A focused autoantigen microarray of candidate NPSLE autoantigens was applied to profile a larger cohort of CSF with patient-matched sera. We identified 137 autoantigens associated with NPSLE. Ingenuity Pathway Analysis revealed that these autoantigens were enriched for functions involved in neurological diseases (score = 43.Anti-proliferating cell nuclear antigen (PCNA was found in the CSF of NPSLE and non-NPSLE patients. The positive rates of 4 autoantibodies in CSF specimens were significantly different between the SLE (i.e., NPSLE and non-NPSLE and control groups: anti-ribosomal protein RPLP0, anti-RPLP1, anti-RPLP2, and anti-TROVE2 (also known as anti-Ro/SS-A. The positive rate for anti-SS-A associated with NPSLE was higher than that for non-NPSLE (31.11% cf. 10.71%; P = 0.045.Further analysis showed that anti-SS-A in CSF specimens was related to neuropsychiatric syndromes of the central nervous system in SLE (P = 0.009. Analysis with Spearman's rank correlation coefficient indicated that the titers of anti-RPLP2 and anti-SS-A in paired CSF and serum specimens significantly correlated. Human proteome microarrays offer a powerful platform to discover novel autoantibodies in CSF samples. Anti-SS-A autoantibodies may be potential CSF markers for NPSLE.

Pulmonary function and autoantibodies in a long-term follow-up of juvenile dermatomyositis patients

DEFF Research Database (Denmark)

Mathiesen, Pernille Raasthøj; Buchvald, Frederik Fouirnaies; Nielsen, Kim G

2014-01-01

outcome, and (iii) identify possible associations between pulmonary impairment and myositis-specific autoantibodies (MSAs).Methods. Fifty-one JDM patients performed conventional spirometry in a cross-sectional follow-up study. The scores of the Myositis Damage Index (MDI), Myositis Damage by visual...... analogue scale (MYODAM-VAS) and physician's global damage assessment were used to estimate JDM outcome. ANAs, MSAs and myositis-associated autoantibodies were analysed in all patients.Results. Forty-two patients (82%) (mean follow-up time 14.3 years) had normal lung function. Four patients (8%) were...

A genome-wide siRNA screen to identify modulators of insulin sensitivity and gluconeogenesis.

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Ruojing Yang

Full Text Available BACKGROUND: Hepatic insulin resistance impairs insulin's ability to suppress hepatic glucose production (HGP and contributes to the development of type 2 diabetes (T2D. Although the interests to discover novel genes that modulate insulin sensitivity and HGP are high, it remains challenging to have a human cell based system to identify novel genes. METHODOLOGY/PRINCIPAL FINDINGS: To identify genes that modulate hepatic insulin signaling and HGP, we generated a human cell line stably expressing beta-lactamase under the control of the human glucose-6-phosphatase (G6PC promoter (AH-G6PC cells. Both beta-lactamase activity and endogenous G6PC mRNA were increased in AH-G6PC cells by a combination of dexamethasone and pCPT-cAMP, and reduced by insulin. A 4-gene High-Throughput-Genomics assay was developed to concomitantly measure G6PC and pyruvate-dehydrogenase-kinase-4 (PDK4 mRNA levels. Using this assay, we screened an siRNA library containing pooled siRNA targeting 6650 druggable genes and identified 614 hits that lowered G6PC expression without increasing PDK4 mRNA levels. Pathway analysis indicated that siRNA-mediated knockdown (KD of genes known to positively or negatively affect insulin signaling increased or decreased G6PC mRNA expression, respectively, thus validating our screening platform. A subset of 270 primary screen hits was selected and 149 hits were confirmed by target gene KD by pooled siRNA and 7 single siRNA for each gene to reduce G6PC expression in 4-gene HTG assay. Subsequently, pooled siRNA KD of 113 genes decreased PEPCK and/or PGC1alpha mRNA expression thereby demonstrating their role in regulating key gluconeogenic genes in addition to G6PC. Last, KD of 61 of the above 113 genes potentiated insulin-stimulated Akt phosphorylation, suggesting that they suppress gluconeogenic gene by enhancing insulin signaling. CONCLUSIONS/SIGNIFICANCE: These results support the proposition that the proteins encoded by the genes identified in

Acute insulin resistance stimulates and insulin sensitization attenuates vascular smooth muscle cell migration and proliferation.

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Cersosimo, Eugenio; Xu, Xiaojing; Upala, Sikarin; Triplitt, Curtis; Musi, Nicolas

2014-08-01

Differential activation/deactivation of insulin signaling, PI-3K and MAP-K pathways by high glucose and palmitate, with/out the insulin sensitizer pioglitazone (PIO), have been previously shown in vascular smooth muscle cells (VSMCs). To determine the biological impact of these molecular changes, we examined VSMC migration and proliferation ("M"&"P") patterns in similar conditions. VSMCs from healthy human coronary arteries were incubated in growth medium and "M"&"P" were analyzed after exposure to high glucose (25 mmol/L) ± palmitate (200 μmol/L) and ± PIO (8 μmol/L) for 5 h. "M"&"P" were assessed by: (1) polycarbonate membrane barrier with chemo-attractants and extended cell protrusions quantified by optical density (OD595 nm); (2) % change in radius area (2D Assay) using inverted microscopy images; and (3) cell viability assay expressed as cell absorbance (ABS) in media. "M" in 25 mmol/L glucose media increased by ~25% from baseline and % change in radius area rose from ~20% to ~30%. The addition of PIO was accompanied by a significant decrease in "M" from 0.25 ± 0.02 to 0.19 ± 0.02; a comparable decline from 0.25 ± 0.02 to 0.18 ± 0.02 was also seen with 25 mmol/L of glucose +200 μmol/L of palmitate. When PIO was coincubated with high glucose plus palmitate there was a 50% reduction in % change in radius. A ~10% increase in ABS, reflecting augmented "P" in media with 25 mmol/L glucose versus control was documented. The addition of PIO reduced ABS from 0.208 ± 0.03 to 0.183 ± 0.06. Both high glucose and palmitate showed ABS of ~0.140 ± 0.02, which decreased with PIO to ~0.120 ± 0.02, indicating "P" was reduced. These results confirm that high glucose and palmitate stimulate VSMCs migration and proliferation in vitro, which is attenuated by coincubation with the insulin sensitizer PIO. Although, we cannot ascertain whether these functional changes are coincident with the activation/deactivation of signal molecules, our findings are consistent with the

An immune response manifested by the common occurrence of annexins I and II autoantibodies and high circulating levels of IL-6 in lung cancer

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Brichory, Franck M.; Misek, David E.; Yim, Anne-Marie; Krause, Melissa C.; Giordano, Thomas J.; Beer, David G.; Hanash, Samir M.

2001-01-01

The identification of circulating tumor antigens or their related autoantibodies provides a means for early cancer diagnosis as well as leads for therapy. The purpose of this study was to identify proteins that commonly induce a humoral response in lung cancer by using a proteomic approach and to investigate biological processes that may be associated with the development of autoantibodies. Aliquots of solubilized proteins from a lung adenocarcinoma cell line (A549) and from lung tumors were subjected to two-dimensional PAGE, followed by Western blot analysis in which individual sera were tested for primary antibodies. Sera from 54 newly diagnosed patients with lung cancer and 60 patients with other cancers and from 61 noncancer controls were analyzed. Sera from 60% of patients with lung adenocarcinoma and 33% of patients with squamous cell lung carcinoma but none of the noncancer controls exhibited IgG-based reactivity against proteins identified as glycosylated annexins I and/or II. Immunohistochemical analysis showed that annexin I was expressed diffusely in neoplastic cells in lung tumor tissues, whereas annexin II was predominant at the cell surface. Interestingly, IL-6 levels were significantly higher in sera of antibody-positive lung cancer patients compared with antibody-negative patients and controls. We conclude that an immune response manifested by annexins I and II autoantibodies occurs commonly in lung cancer and is associated with high circulating levels of an inflammatory cytokine. The proteomic approach we have implemented has utility for the development of serum-based assays for cancer diagnosis as we report in this paper on the discovery of antiannexins I and/or II in sera from patients with lung cancer. PMID:11504947

Anti-M(3) muscarinic cholinergic autoantibodies from patients with primary Sjögren's syndrome trigger production of matrix metalloproteinase-3 (MMP-3) and prostaglandin E(2) (PGE(2)) from the submandibular glands.

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Reina, Silvia; Sterin-Borda, Leonor; Passafaro, Daniela; Borda, Enri

2011-05-01

We demonstrated that serum immunoglobulin G (IgG) from patients with primary Sjögren's syndrome (pSS), interacting with the second extracellular loop of human glandular M(3) muscarinic acetylcholine receptors (M(3) mAChR), trigger the production of matrix metalloproteinase-3 (MMP-3) and prostaglandin E(2) (PGE(2)). Enzyme-linked immunosorbent assays (ELISAs) were performed in the presence of M(3) mAChR synthetic peptide as antigen to detect in serum the autoantibodies. Further, MMP-3 and PGE(2) production were determined in the presence of anti-M(3) mAChR autoantibodies. An association was observed between serum and anti-M(3) mAChR autoantibodies and serum levels of MMP-3 and PGE(2) in pSS patients. Thus, we established that serum anti-M(3) mAChR autoantibodies, MMP-3 and PGE(2) may be considered to be early markers of pSS associated with inflammation. Affinity-purified anti-M(3) mAChR peptide IgG from pSS patients, whilst stimulating salivary-gland M(3) mAChR, causes an increase in the level of MMP-3 and PGE(2) as a result of the activation of phospholipase A(2) (PLA(2)) and cyclooxygenase-2 (COX-2) (but not COX-1). These results provide a novel insight into the role that cholinoceptor antibodies play in the development of glandular inflammation. This is the first report showing that an antibody interacting with glandular mAChR can induce the production of pro-inflammatory mediators (MMP-3/PGE(2)). Copyright © 2010 Elsevier Ltd. All rights reserved.

Thyroid profile and autoantibodies in Type 1 diabetes subjects: A perspective from Eastern India

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Debmalya Sanyal

2017-01-01

Full Text Available Context: There has been a rise in the incidence of type 1 diabetes mellitus (T1DM in India. The prevalence of thyroid autoantibodies and thyroid dysfunction is common in T1DM. Aims: The aim of this study is to determine the incidence of thyroid dysfunction and thyroid autoantibodies in T1DM subjects, without any history of thyroid disease, and the prevalence of glutamic acid decarboxylase (GAD antibody, Islet antigen-2 antibody (IA2, thyroid peroxidase (TPO, and thyroglobulin autoantibodies (Tg-AB in T1DM subjects. Settings and Design: This was a cross-sectional clinical-based study. Subjects and Methods: Fifty subjects (29 males, 31 females with T1DM and without any history of thyroid dysfunction were included in the study. All subjects were tested for GAD antibody, IA2 antibody, TPO antibody, thyroglobulin antibody, free thyroxine, and thyroid-stimulating hormone. Statistical Analysis Used: A Chi-square/pooled Chi-square test was used to assess the trends in the prevalence of hypothyroidism. A two-tailed P< 0.05 was considered statistically significant. Results: The mean age of the subjects was 23.50 years. 9.8% of subjects were below the age of 12 years, 27.45% of subjects were of age 12–18 years, 37.25% of subjects were of age 19–30 years, and 25.49% of subjects were above 30 years. 78% were positive autoantibody for GAD, 30% for IA-2, 24% for TPO, and 16% were positive for Tg-AB. A total of 6.0% of T1DM subjects had evidence of clinical hypothyroidism, but the prevalence of subclinical hyperthyroidism (SCH varied from 32% to 68.0% for we considered different definitions of SCH as advocated by different guidelines. All subjects with overt hypothyroidism had positive GAD and thyroid autoantibodies. One (2% subject had clinical hyperthyroidism with strongly positive GAD, TPO, and Tg-AB. Conclusions: We found a high prevalence of GAD, IA2, TPO, and Tg-AB in our T1DM subjects. A substantial proportion of our subjects had undiagnosed thyroid

Starvation increases insulin sensitivity and reduces juvenile hormone synthesis in mosquitoes.

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Meritxell Perez-Hedo

Full Text Available The interactions between the insulin signaling pathway (ISP and juvenile hormone (JH controlling reproductive trade-offs are well documented in insects. JH and insulin regulate reproductive output in mosquitoes; both hormones are involved in a complex regulatory network, in which they influence each other and in which the mosquito's nutritional status is a crucial determinant of the network's output. Previous studies reported that the insulin-TOR (target of rapamacyn signaling pathway is involved in the nutritional regulation of JH synthesis in female mosquitoes. The present studies further investigate the regulatory circuitry that controls both JH synthesis and reproductive output in response to nutrient availability.We used a combination of diet restriction, RNA interference (RNAi and insulin treatments to modify insulin signaling and study the cross-talk between insulin and JH in response to starvation. JH synthesis was analyzed using a newly developed assay utilizing fluorescent tags.Our results reveal that starvation decreased JH synthesis via a decrease in insulin signaling in the corpora allata (CA. Paradoxically, starvation-induced up regulation of insulin receptor transcripts and therefore "primed" the gland to respond rapidly to increases in insulin levels. During this response to starvation the synthetic potential of the CA remained unaffected, and the gland rapidly and efficiently responded to insulin stimulation by increasing JH synthesis to rates similar to those of CA from non-starved females.

Preferential recognition of auto-antibodies against 4-hydroxynonenal modified DNA in the cancer patients.

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Faisal, Mohammad; Shahab, Uzma; Alatar, Abdulrahman A; Ahmad, Saheem

2017-11-01

The structural perturbations in DNA molecule may be caused by a break in a strand, a missing base from the backbone, or a chemically changed base. These alterations in DNA that occurs naturally can result from metabolic or hydrolytic processes. DNA damage plays a major role in the mutagenesis, carcinogenesis, aging and various other patho-physiological conditions. DNA damage can be induced through hydrolysis, exposure to reactive oxygen species (ROS) and other reactive carbonyl metabolites including 4-hydroxynonenal (HNE). 4-HNE is an important lipid peroxidation product which has been implicated in the mutagenesis and carcinogenesis processes. The present study examines to probe the presence of auto-antibodies against 4-hydroxynonenal damaged DNA (HNE-DNA) in various cancer subjects. In this study, the purified calf thymus DNA was damaged by the action of 4-HNE. The DNA was incubated with 4-HNE for 24 h at 37°C temperature. The binding characteristics of cancer auto-antibodies were assessed by direct binding and competitive inhibition ELISA. DNA modifications produced hyperchromicity in UV spectrum and decreased fluorescence intensity. Cancer sera exhibited enhanced binding with the 4-HNE modified calf thymus DNA as compared to its native conformer. The 4-HNE modified DNA presents unique epitopes which may be one of the factors for the auto-antibody induction in cancer patients. The HNE modified DNA presents unique epitopes which may be one of the factors for the autoantibody induction in cancer patients. © 2017 Wiley Periodicals, Inc.

Concentrated insulins: the new basal insulins

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Lamos EM

2016-03-01

Full Text Available Elizabeth M Lamos,1 Lisa M Younk,2 Stephen N Davis3 1Division of Endocrinology, Diabetes and Nutrition, 2Department of Medicine, University of Maryland School of Medicine, 3Department of Medicine, University of Maryland Medical Center, Baltimore, MD, USA Introduction: Insulin therapy plays a critical role in the treatment of type 1 and type 2 diabetes mellitus. However, there is still a need to find basal insulins with 24-hour coverage and reduced risk of hypoglycemia. Additionally, with increasing obesity and insulin resistance, the ability to provide clinically necessary high doses of insulin at low volume is also needed. Areas covered: This review highlights the published reports of the pharmacokinetic (PK and glucodynamic properties of concentrated insulins: Humulin-R U500, insulin degludec U200, and insulin glargine U300, describes the clinical efficacy, risk of hypoglycemic, and metabolic changes observed, and finally, discusses observations about the complexity of introducing a new generation of concentrated insulins to the therapeutic market. Conclusion: Humulin-R U500 has a similar onset but longer duration of action compared with U100 regular insulin. Insulin glargine U300 has differential PK/pharmacodynamic effects when compared with insulin glargine U100. In noninferiority studies, glycemic control with degludec U200 and glargine U300 is similar to insulin glargine U100 and nocturnal hypoglycemia is reduced. Concentrated formulations appear to behave as separate molecular entities when compared with earlier U100 insulin analog compounds. In the review of available published data, newer concentrated basal insulins may offer an advantage in terms of reduced intraindividual variability as well as reducing the injection burden in individuals requiring high-dose and large volume insulin therapy. Understanding the PK and pharmacodynamic properties of this new generation of insulins is critical to safe dosing, dispensing, and administration

Autoantibodies to neurotransmitter receptors and ion channels: from neuromuscular to neuropsychiatric disorders

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Pilar eMartinez-Martinez

2013-09-01

Full Text Available Changes of voltage-gated ion channels and ligand-gated receptor channels caused by mutation or autoimmune attack are the cause of so-called channelopathies in the central and peripheral nervous system. We present the pathophysiology of channelopathies of the neuromuscular junction in terms of loss-of-function and gain-of-function principles. Autoantibodies generally have reduced access to the CNS, but in some cases this is enough to cause disease. A review is provided of recent findings implicating autoantibodies against ligand–activated receptor channels and potassium channels in psychiatric and neurological disorders, including schizophrenia and limbic encephalitis. The emergence of channelopathy-related neuropsychiatric disorders has implications for research and practice.

Correlation between the Plasma Insulin and Glucose Concentration in Normal Korean Adults

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Lee, Jang Kyu; Sung, Ho Kyung; Kim, Jin Eui [Radiological Research Institute, Seoul (Korea, Republic of)

1971-09-15

The correlation between the plasma insulin, and glucose concentration was studied in healthy Korean adults consisting of 20 males and 22 females of 16 to 38 years of age. The blood samples of above subjects were obtained through cubital vein at arbitrary times during their usual working hours. Plasma insulin was assayed by means of double antibody system of radioimmunoassay technics, and blood glucose was determined by means of Van Slyke-Folch method. Results were as follows : 1. There were no differences in the blood sugar levels in relation to the plasma insulin concentration either by sex or age. 2. In the case, when the plasma insulin concentration was within 50 mmuU/ml, the correlation between the insulin, and glucose concentration existed, the ratio of which was expressed as; Plasma glucose concentration (mg/dl)=91.9 + 0.08 X Insulin concentration r=0.62. 3. Insulinogenic index was 12.4%, which was somewhat higher than other reports. 4. It is suggested that the correlation between plasma insulin and glucose concentration could be determined at arbitrary times instead of fasting times.

Thyroid autoantibodies and differentiated thyroid cancer: revue of 662 cases

International Nuclear Information System (INIS)

Izembart, M.; Dagousset, F.; Chevalier, A.; Hassid, V.; Leger, A.; Barritault, L.; Clerc, J.

1999-01-01

The incidence of thyroid autoantibodies is clearly increased in patients with differentiated thyroid cancer. The aim of this study was to re-evaluate frequency and evolution of anti-thyroglobulin and anti-microsomal (anti-peroxidase) autoantibodies in 662 patients with thyroid carcinoma treated with 131 radioiodine. Ours results obtained with 'classical' methods confirmed others earlier reports. When using more sensitive methods to detect thyroglobulin antibodies we obtained an increase in positive results and a more frequent association with anti-microsomal antibodies. Antibodies became undetectable with a variable period, ranging from a few months to 13 years in one case. If we suppose that the disappearance of antibodies is linked to the thyroid tissue disappearance, thyroid cancer follow up ought to include anti-thyroglobulin and anti-peroxidase antibodies, both directed against thyroid antigens. A decrease of both antibodies seems to indicate a favorable prognostic factor whereas an increase may suggest relapse. (author)

Role of Natural Autoantibodies in Ugandans With Rheumatic Heart Disease and HIV

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Daniel M. Huck

2016-03-01

Interpretation: We found that HIV and RHD are associated with alterations in natural autoantibody responses previously linked to an increased risk for atherosclerosis and autoimmune inflammatory disease.

Characterization of autoantibodies in autoimmune hemolytic anemia following treatment with interferon alfa

International Nuclear Information System (INIS)

Bencomo Hernandez, Antonio; Gutierrez Diaz, Adys; Avila Cabrera, Onel; Rodriguez, Luis Ramon

2012-01-01

We studied 13 patients with chronic myeloid leukemia and autoimmune hemolytic anemia induced by interferon alfa. They underwent tests for immune protein detection and characterization of IgG subclasses in RBCs by direct antiglobulin test (PAD) and the microplate technique. Also they were applied ELISA test for quantifying immunoglobulins in the red blood cells. It was detected the presence of IgG and C3 in 53.84 % of cases, IgG alone in 23.07 % and in 15.38 % were identified IgG and IgA autoantibodies. In 11 patients the presence of IgG1 was showed and also in one case the subclass IgG3 autoantibodies was identified. The ELISA detected antibodies at concentrations of 183 IgG molecules per erythrocyte in a patient with negative PAD. In high-grade hemolysis patients, it was found a concentration of autoantibodies between 1 500 and 3 180 molecules of IgG per erythrocyte, while in low-grade hemolysis patients it behaved between 183 and 1 000 molecules. There was a negative correlation between Hb and plasma haptoglobin values with the number of IgG molecules per erythrocyte and a positive correlation between the latter with the reticulocyte count

Serum auto-antibody testing for early diagnosis of breast cancer

International Nuclear Information System (INIS)

Parvez, S.

2012-01-01

The aim of this thesis is generate prototype-tests suitable for randomized prospective validation of auto-antibody based diagnostic testing using serum samples. Tumours can stimulate the production of auto-antibodies against autologous cellular proteins known as TAAs (tumour associated antigens). This discovery has lead to a possibility of using the auto-antibodies as serological tools for the early diagnosis and management of breast cancer. The recombinant proteins expressed by the SEREX clones, identified from screenings of brain and lung tumour, were used for the production of the protein microarrays and macroarrays. The protein microarrays showed better correlation between the replicates of the serum samples used. The optimized protocols were used for the subsequent experiments. A sizable panel of 642 clone-proteins was selected by marker-screening on protein macroarrays with 38000 clones. These 642 clone-proteins were used to generate protein microarrays that differentiated serum samples from breast cancer patients and controls. Antigenic peptide motifs were identified by in-silico analysis of 642 clone-proteins and peptide arrays were generated using synthetically generated peptides. Comparative studies between protein microarrays and peptide microarrays were done using breast cancer and healthy control samples. Simultaneously, SEREX strategy was used for the identification of the immunogenic TAAs. I identified 192 cDNA expression clones derived from breast cancer tissue samples and the selection was done using breast cancer sera. The genes corresponding to these clones were found over-represented for the pathways that are known to be associated with cancers. These genes showed typical features of TAAs, like over-expression, mutations and fusion genes. (author)

Monomeric insulins and their experimental and clinical implications.

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Brange, J; Owens, D R; Kang, S; Vølund, A

1990-09-01

Due to the inherent pharmacokinetic properties of available insulins, normoglycemia is rarely, if ever, achieved in insulin-dependent diabetic patients without compromising their quality of life. Subcutaneous insulin absorption is influenced by many factors, among which the associated state of insulin (hexameric) in pharmaceutical formulation may be of importance. This review describes the development of a series of human insulin analogues with reduced tendency to self-association that, because of more rapid absorption, are better suited to meal-related therapy. DNA technology has made it possible to prepare insulins that remain dimeric or even monomeric at high concentration by introducing one or a few amino acid substitutions into human insulin. These analogues were characterized and used for elucidating the mechanisms involved in subcutaneous absorption and were investigated in preliminary clinical studies. Their relative receptor binding and in vitro potency (free-fat cell assay), ranging from 0.05 to 600% relative to human insulin, were strongly correlated (r = 0.97). In vivo, most of the analogues exhibited approximately 100% activity, explainable by a dominating receptor-mediated clearance. This was confirmed by clamp studies in which correlation between receptor binding and clearance was observed. Thus, an analogue with reduced binding and clearance gives higher circulating concentrations, counterbalancing the reduced potency at the cellular level. Absorption studies in pigs revealed a strong inverse correlation (r = 0.96) between the rate of subcutaneous absorption and the mean association state of the insulin analogues. These studies also demonstrated that monomeric insulins were absorbed three times faster than human insulin. In healthy subjects, rates of disappearance from subcutis were two to three times faster for dimeric and monomeric analogues than for human insulin. Concomitantly, a more rapid rise in plasma insulin concentration and an earlier

Shared Genetic Basis for Type 1 Diabetes, Islet Autoantibodies, and Autoantibodies Associated With Other Immune-Mediated Diseases in Families With Type 1 Diabetes

DEFF Research Database (Denmark)

Brorsson, Caroline Anna; Pociot, Flemming

2015-01-01

) in autoimmune gastritis, transglutaminase (TGA) in celiac disease, and 21-hydroxylase (21-OHA) in autoimmune hypoadrenalism. In addition to the MHC region, we identify SNPs in five susceptibility loci (IFIH1, PTPN22, SH2B3, BACH2, and CTLA4) as significantly associated with more than one autoantibody at a false...

Chronic malaria revealed by a new fluorescence pattern on the antinuclear autoantibodies test.

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Benjamin Hommel

Full Text Available BACKGROUND: Several clinical forms of malaria such as chronic carriage, gestational malaria or hyper-reactive malarial splenomegaly may follow a cryptic evolution with afebrile chronic fatigue sometimes accompanied by anemia and/or splenomegaly. Conventional parasitological tests are often negative or not performed, and severe complications may occur. Extensive explorations of these conditions often include the search for antinuclear autoantibodies (ANA. METHODS: We analysed fluorescence patterns in the ANA test in patients with either chronic cryptic or acute symptomatic malaria, then conducted a one-year prospective study at a single hospital on all available sera drawn for ANA detections. We then identified autoantibodies differentially expressed in malaria patients and in controls using human protein microarray. RESULTS: We uncovered and defined a new, malaria-related, nucleo-cytoplasmic ANA pattern displaying the specific association of a nuclear speckled pattern with diffuse cytoplasmic perinuclearly-enhanced fluorescence. In the one-year prospective analysis, 79% of sera displaying this new nucleo-cytoplasmic fluorescence were from patients with malaria. This specific pattern, not seen in other parasitic diseases, allowed a timely reorientation of the diagnosis toward malaria. To assess if the autoantibody immune response was due to autoreactivity or molecular mimicry we isolated 42 autoantigens, targets of malarial autoantibodies. BLAST analysis indicated that 23 of recognized autoantigens were homologous to plasmodial proteins suggesting autoimmune responses directly driven by the plasmodial infection. CONCLUSION: In patients with malaria in whom parasitological tests have not been performed recognition of this new, malaria-related fluorescence pattern on the ANA test is highly suggestive of the diagnosis and triggers immediate, easy confirmation and adapted therapy.

Development of an Aquaporin-4 Orthogonal Array of Particle-Based ELISA for Neuromyelitis Optica Autoantibodies Detection.

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Francesco Pisani

Full Text Available Serological markers of Nuromyelitis Optica (NMO, an autoimmune disorder of the central nervous system, are autoantibodies targeting the astrocytic water channel aquaporin-4 (AQP4. We have previously demonstrated that the main epitopes for these autoantibodies (AQP4-IgG are generated by the supramolecular arrangement of AQP4 tetramers into an Orthogonal Array of Particles (OAPs. Many tests have been developed to detect AQP4-IgG in patient sera but several procedural issues affect OAP assembly and consequently test sensitivity. To date, the protein based ELISA test shows the lowest sensitivity while representing a valid alternative to the more sensitive cell based assay (CBA, which, however, shows economic, technical and interpretation problems. Here we have developed a high perfomance ELISA in which native OAPs are used as the molecular target. To this aim a native size exclusion chromatography method has been developed to isolate integral, highly pure and AQP4-IgG-recognized OAPs from rat brain. These OAPs were immobilized and oriented on a plastic plate by a sandwich approach and 139 human sera were tested, including 67 sera from NMO patients. The OAP-ELISA showed a 99% specificity and a higher sensitivity (91% compared to the CBA test. A comparative analysis revealed an end-point titer three orders of magnitude higher than the commercial ELISA and six times higher than our in-house CBA test. We show that CNS-extracted OAPs are crucial elements in order to perform an efficient AQP4-IgG test and the OAP-ELISA developed represents a valid alternative to the CBA currently used.

CCK increases the transport of insulin into the brain.

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May, Aaron A; Liu, Min; Woods, Stephen C; Begg, Denovan P

2016-10-15

Food intake occurs in bouts or meals, and numerous meal-generated signals have been identified that act to limit the size of ongoing meals. Hormones such as cholecystokinin (CCK) are secreted from the intestine as ingested food is being processed, and in addition to aiding the digestive process, they provide a signal to the brain that contributes to satiation, limiting the size of the meal. The potency of CCK to elicit satiation is enhanced by elevated levels of adiposity signals such as insulin. In the present experiments we asked whether CCK and insulin interact at the level of the blood-brain barrier (BBB). We first isolated rat brain capillary endothelial cells that comprise the BBB and found that they express the mRNA for both the CCK1R and the insulin receptor, providing a basis for a possible interaction. We then administered insulin intraperitoneally to another group of rats and 15min later administered CCK-8 intraperitoneally to half of those rats. After another 15min, CSF and blood samples were obtained and assayed for immunoreactive insulin. Plasma insulin was comparably elevated above baseline in both the CCK-8 and control groups, indicating that the CCK had no effect on circulating insulin levels given these parameters. In contrast, rats administered CCK had CSF-insulin levels that were more than twice as high as those of control rats. We conclude that circulating CCK greatly facilitates the transport of insulin into the brain, likely by acting directly at the BBB. These findings imply that in circumstances in which the plasma levels of both CCK and insulin are elevated, such as during and soon after meals, satiation is likely to be due, in part, to this newly-discovered synergy between CCK and insulin. Copyright © 2016 Elsevier Inc. All rights reserved.

Human c-peptide immunoreactivity (CPR) in blood and urine - evaluation of a radioimmunoassay method and its clinical applications

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Kuzuya, T; Matsuda, A; Saito, T; Yoshida, S

1976-01-01

A double-antibody radioimmunoassay method, using synthetic human connecting peptide as an immunizing antigen and standard, was evaluated for clinical assay of blood and urine samples. Normal fasting blood connecting peptide immunoreacivity (CPR) was 2.45 +- 0.96 ng/ml, increasing promptly after a 50 g oral glucose load, but somewhat slower than insulin. Molar concentration of CPR exceeded that of insulin. CPR responses to glucose were subnormal in diabetics, very low in juvenile-type cases, and often poor in patients on insulin treatment. Fasting CPR levels were elevated in patients on corticosteroid treatment and with uraemia. A patient with insulin 'auto-antibody' had high serum CPR. A considerable amount of CPR appeared in urine. Normal daily excretion of CPR was 1.52 +- 0.55 ..mu..g/kg or 55.1 +- 18.2 ng/mg creatinine. Urine CPR was very low in juvenile-type diabetics, and elevated in patients on corticosteroid treatment. The results confirm that blood and urine CPR are useful measures of the endocrine pancreatic function.

Low Frequencies of Autoimmunity-Associated PTPN22 Polymorphisms in MODY Patients, Including Those Transiently Expressing Islet Cell Autoantibodies.

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Heneberg, Petr; Malá, Milena; Yorifuji, Tohru; Gat-Yablonski, Galia; Lebenthal, Yael; Tajima, Toshihiro; Nogaroto, Viviane; Rypáčková, Blanka; Kocková, Lucie; Urbanová, Jana; Anděl, Michal

2015-01-01

The protein tyrosine phosphatase nonreceptor type 22 (PTPN22) gene encodes lymphoid tyrosine phosphatase (LYP), which is expressed primarily in lymphoid tissues. The functional but geographically highly variable PTPN22 single-nucleotide polymorphisms (SNPs), particularly c.1858C>T, contribute to the onset and progression of autoimmunity-associated diseases and facilitate the expression of disease-associated autoantibodies. In Central Europe, 17-25% of patients with monogenic diabetes (maturity-onset diabetes of the young, MODY) transiently express islet cell autoantibodies. We addressed the links between the functional and geographically variable PTPN22 SNPs with MODY manifestation and the expression of islet cell autoantibodies in 276 MODY patients who originated from four regions (the Czech Republic, Israel, Japan and Brazil). The frequency of PTPN22 polymorphisms in the MODY patients was similar to those in geographically matched healthy populations, with the exception of c.788G>A, the minor allele frequency of which was significantly elevated in the Czech hepatocyte nuclear factor 1-α (HNF1A) MODY patients [odds ratio (OR) 4.8, 95% confidence interval (CI) 2.2-10.7] and the Brazilian MODY patients (OR 8.4, 95% CI 1.8-39.1). A barely significant increase in the c.788G>A minor allele was also detected in the islet cell autoantibody-positive Czech MODY patients. However, c.788A behaves as a loss-of-function mutant in T cells, and thus protects against autoimmunity. MODY patients (including islet cell autoantibody-positive cases) do not display any increase in autoimmunity-associated PTPN22 alleles. The absence of autoimmunity-associated PTPN22 alleles was also demonstrated in latent autoimmune diabetes in adults, which suggests that the slow kinetics of the onset of autoantibodies is subject to a regulation that is different from that experienced in type 1 diabetes and other autoimmune disorders. © 2015 S. Karger AG, Basel.

Autoimmune gastro-pancreatitis with anti-protein disulfide isomerase-associated 2 autoantibody in Aire-deficient BALB/cAnN mice.

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Hironori Kurisaki

Full Text Available Although the autoimmune regulator (Aire knockout (KO mouse model has been reported to present various organ-specific autoimmune diseases depending on genetic background, autoimmune pancreatitis in mice of BALB/c background has not yet been reported. Here, we report that Aire KO mice with BALB/cAnN background showed significant lymphoid cell infiltration in the pancreas and stomach. To examine whether the phenotype in the pancreas and stomach is due to autoimmune reaction associated with autoantibody production, indirect immunofluorescence staining followed by Western blot analysis was performed. Consequently, the autoantibody against pancreas and stomach was detected in the sera of Aire KO mice, and the target antigen of the autoantibody was identified as protein disulfide isomerase-associated 2 (Pdia2, which was reported to be expressed preferentially in the pancreas and stomach. Thus, Aire KO mice of BALB/cAnN background can serve as a useful animal model for autoimmune gastro-pancreatitis with anti-Pdia2 autoantibody production.

Autoimmune gastro-pancreatitis with anti-protein disulfide isomerase-associated 2 autoantibody in Aire-deficient BALB/cAnN mice.

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Kurisaki, Hironori; Nagao, Yukihiro; Nagafuchi, Seiho; Mitsuyama, Masao

2013-01-01

Although the autoimmune regulator (Aire) knockout (KO) mouse model has been reported to present various organ-specific autoimmune diseases depending on genetic background, autoimmune pancreatitis in mice of BALB/c background has not yet been reported. Here, we report that Aire KO mice with BALB/cAnN background showed significant lymphoid cell infiltration in the pancreas and stomach. To examine whether the phenotype in the pancreas and stomach is due to autoimmune reaction associated with autoantibody production, indirect immunofluorescence staining followed by Western blot analysis was performed. Consequently, the autoantibody against pancreas and stomach was detected in the sera of Aire KO mice, and the target antigen of the autoantibody was identified as protein disulfide isomerase-associated 2 (Pdia2), which was reported to be expressed preferentially in the pancreas and stomach. Thus, Aire KO mice of BALB/cAnN background can serve as a useful animal model for autoimmune gastro-pancreatitis with anti-Pdia2 autoantibody production.

Breed differences in development of anti-insulin antibodies in diabetic dogs and investigation of the role of dog leukocyte antigen (DLA) genes.

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Holder, Angela L; Kennedy, Lorna J; Ollier, William E R; Catchpole, Brian

2015-10-15

Administration of insulin for treatment of diabetes mellitus in dogs can stimulate an immune response, with a proportion of animals developing anti-insulin antibodies (AIA). For an IgG antibody response to occur, this would require B cell presentation of insulin peptides by major histocompatibility complex (MHC) class II molecules, encoded by dog leukocyte antigen (DLA) genes, in order to receive T-cell help for class switching. DLA genes are highly polymorphic in the dog population and vary from breed to breed. The aim of the present study was to evaluate AIA reactivity in diabetic dogs of different breeds and to investigate whether DLA genes influence AIA status. Indirect ELISA was used to determine serological reactivity to insulin in diabetic dogs, treated with either a porcine or bovine insulin preparation. DLA haplotypes for diabetic dogs were determined by sequence-based typing of DLA-DRB1, -DQA1 and -DQB1 loci. Significantly greater insulin reactivity was seen in treated diabetic dogs (n=942) compared with non-diabetic dogs (n=100). Relatively few newly diagnosed diabetic dogs (3/109) were found to be AIA positive, although this provides evidence that insulin autoantibodies might be involved in the pathogenesis of the disease in some cases. Of the diabetic dogs treated with a bovine insulin preparation, 52.3% (182/348) were AIA positive, compared with 12.6% (75/594) of dogs treated with a porcine insulin preparation, suggesting that bovine insulin is more immunogenic. Breeds such as dachshund, Cairn terrier, miniature schnauzer and Tibetan terrier were more likely to develop AIA, whereas cocker spaniels were less likely to develop AIA, compared with crossbreed dogs. In diabetic dogs, DLA haplotype DRB1*0015--DQA1*006--DQB1*023 was associated with being AIA positive, whereas the haplotype DLA-DRB1*006--DQA1*005--DQB1*007 showed an association with being AIA negative. These research findings suggest that DLA genes influence AIA responses in treated diabetic

Autoantibody levels in myositis patients correlate with clinical response during B cell depletion with rituximab.

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Aggarwal, Rohit; Oddis, Chester V; Goudeau, Danielle; Koontz, Diane; Qi, Zengbiao; Reed, Ann M; Ascherman, Dana P; Levesque, Marc C

2016-06-01

To determine the longitudinal trends in serum levels of four myositis-associated autoantibodies: anti-Jo-1, -transcription intermediary factor 1 γ (TIF1-γ), -signal recognition particle (SRP) and -Mi-2, after B cell depletion with rituximab, and to determine the longitudinal association of these autoantibody levels with disease activity as measured by myositis core-set measures (CSMs). Treatment-resistant adult and pediatric myositis subjects (n = 200) received rituximab in the 44-week Rituximab in Myositis Trial. CSMs [muscle enzymes, manual muscle testing (MMT), physician and patient global disease activity, HAQ, and extramuscular disease activity] were evaluated monthly and anti-Jo-1 (n = 28), -TIF1-γ (n = 23), -SRP (n = 25) and -Mi-2 (n = 26) serum levels were measured using validated quantitative ELISAs. Temporal trends and the longitudinal relationship between myositis-associated autoantibodies levels and CSM were estimated using linear mixed models. Following rituximab, anti-Jo-1 levels decreased over time (P myositis subjects decreased after B cell depletion and were correlated with changes in disease activity, whereas anti-SRP levels were only associated with longitudinal muscle enzyme levels. The strong association of anti-Jo-1 levels with clinical outcomes suggests that anti-Jo-1 autoantibodies may be a good biomarker for disease activity. © The Author 2016. Published by Oxford University Press on behalf of the British Society for Rheumatology. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Hyperinsulinemia is associated with increased soluble insulin receptors release from hepatocytes

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Marcia eHiriart

2014-06-01

Full Text Available It has been generally assumed that insulin circulates freely in blood. However it can also interact with plasma proteins. Insulin receptors are located in the membrane of target cells and consist of an alpha and beta subunits with a tyrosine kinase cytoplasmic domain. The ectodomain, called soluble insulin receptor (SIR has been found elevated in patients with diabetes mellitus. We explored if insulin binds to SIRs in circulation under physiological conditions and hypothesize that this SIR may be released by hepatocytes in response to high insulin concentrations. The presence of SIR in rat and human plasmas and the culture medium of hepatocytes was explored using Western blot analysis. A purification protocol was performed to isolated SIR using affinity, gel filtration and ion exchange chromatographies. A modified reverse hemolytic plaque assay was used to measure SIR release from cultured hepatocytes. Incubation with 1 nmol l-1 insulin induces the release of the insulin receptor ectodomains from normal rat hepatocytes. This effect can be partially prevented by blocking protease activity. Furthermore, plasma levels of SIR were higher in a model of metabolic syndrome, where rats are hyperinsulinemic. We also found increased SIR levels in hyperinsulinemic humans. SIR may be an important regulator of the amount of free insulin in circulation. In hyperinsulinemia the amount of this soluble receptor increases, this could lead to higher amounts of insulin bound to this receptor, rather than free insulin, which is the biologically active form of the hormone. This observation could enlighten the mechanisms of insulin resistance.

Prognostic relevance of Bmi-1 expression and autoantibodies in esophageal squamous cell carcinoma

International Nuclear Information System (INIS)

Liu, Wan-li; Li, Man-zhi; Song, Li-bing; Zeng, Mu-sheng; Guo, Xian-zhi; Zhang, Lan-jun; Wang, Jun-ye; Zhang, Ge; Guan, Su; Chen, Yu-min; Kong, Qing-li; Xu, Li-hua

2010-01-01

Overexpression of Bmi-1 has been observed in a variety of cancers, and it has been suggested to be an independent prognostic marker for the patients. The objective of this study was to determine the level of Bmi-1 expression or its autoantibodies in human esophageal squamous cell carcinoma (ESCC) and to correlate it with clinicopathologic data. We first examined Bmi-1 expression in ESCC cell lines and tumor samples by RT-PCR and Western blot analysis. We then analyzed Bmi-1 protein expression in 171 clinicopathologically characterized ESCC cases by immunohistochemistry. In addition, we detected its autoantibodies in sera of patients with ESCC by ELISA. We found that Bmi-1 expression was higher in the immortalized cells, cancer cell lines and most cancer tissue than in non-tumorous control tissue at both mRNA and protein level. In addition, Bmi-1 expression was observed in 64.3% (110 of 171) archive ESCC specimen by immunohistochemistry analysis, and the location of Bmi-1 in ESCC was in the nuclei instead of cytoplasm of tumor cells. There was a significant difference of Bmi-1 expression in patients categorized according to stage (P = 0.003) and pN classification (P = 0.047). Multivariate analysis suggested that Bmi-1 expression was an independent prognostic marker for ESCC patients. A prognostic significance of Bmi-1 was also found in the subgroup of T3~T4 and N1 tumor classification. Bmi-1 autoantibodies were detected in sera of 39.0% (62 of 159) ESCC patients. The correlations between anti-Bmi-1 antibodies and tumor stage (P = 0.040), or lymph node status (P < 0.001) were significant. Our results suggest that Bmi-1 protein is a valuable marker of ESCC progression. The presence of Bmi-1 autoantibodies in sera from patients with ESCC may have clinical utility in esophageal cancer diagnosis

LKM1 autoantibodies in chronic hepatitis C infection: a case of molecular mimicry?

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Marceau, Gabriel; Lapierre, Pascal; Béland, Kathie; Soudeyns, Hugo; Alvarez, Fernando

2005-09-01

Anti-liver-kidney microsome type 1 (LKM1) autoantibodies directed against the cytochrome P450 2D6 (CYP2D6) are considered specific markers of type 2 autoimmune hepatitis, but are also found in 5% of sera from patients chronically infected by hepatitis C virus (HCV). Molecular mimicry between HCV proteins and CYP2D6 has been proposed to explain the emergence of these autoantibodies. Anti-LKM1 autoantibodies from hepatitis C-infected patients were affinity-purified against immobilized CYP2D6 protein and used to screen a phage display library. CYP2D6 conformational epitopes were identified using phage display analysis and the identification of statistically significant pairs (SSPs). Cross-reactivity between CYP2D6 and HCV protein candidates was tested by immunoprecipitation. Nineteen different clones were isolated, and their sequencing resulted in the mapping of a conformational epitope to the region of amino acids 254-288 of CYP2D6. Candidate HCV proteins for molecular mimicry included: core, E2, NS3 and NS5a. Affinity-purified autoantibodies from HCV+/LKM1+ patients immunoprecipitated either NS3, NS5a, or both, and these reactivities were specifically inhibited by immobilized CYP2D6. In conclusion, HCV+/LKM1+ sera recognize a specific conformational epitope on CYP2D6 between amino acids 254 to 288, the region that contains the major linear epitope in type 2 autoimmune hepatitis patients. Cross-reactivity due to molecular mimicry at the B-cell level was shown between the CYP2D6 and the HCV NS3 and NS5a proteins and could explain the presence of anti-LKM1 in patients chronically infected with HCV. Further investigation of the role played by this molecular mimicry in HCV-infected patients may lead to more specific strategies for diagnosis and treatment.

Immunodetection and quantification of insulin-like antigens in sprouts: development of an efficient functional food

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Manju Pathak

2011-11-01

Full Text Available Background: Hormone Insulin is a drug used for the treatment of type 1 and type 2 Diabetes Mellitus. Insulin used in this experiment is derived from bovine and pork pancreas, as well as through recombinant technology. Patients with diabetes mellitus face an inability to utilize glucose from blood due to either less secretion of insulin, or the inability of the insulin to act; As a result of this glucose levels in the blood rise. The prevention and treatment of type 2 Diabetes Mellitus one is world’s major public health issues. Natural alternatives have a big role to play in this field. This study aims at discovering functional foods rich in Insulin like proteins. Here we are reporting Insulin-like proteins synthesizing during the embryo development stage of Glycine max: soybean, Vigna radiata: moong and Vigna unguiculata: cowpea seeds. Hence, germination transforms these seeds containing human insulin like proteins.Methods: In our investigation we have provided protein extraction with Enzyme-linked immunosorbent assay (ELISA. The plant materials weighing 1g were crushed in mortar and pestle, and the protein from the plant materials was extracted with 20 ml of 0.05 M sodium phosphate buffer (pH 7.6. The suspensions were centrifuged at 6000 rpm for 15 min, and the clear supernatants were subjected to Enzyme linked immunosorbent assay (ELISA for the detection of insulin-like proteins. We have used USDA nutritional data sources for the analysis of new products. Results: Our results demonstrate that Insulin is not expressed in dry mature dormant seeds, but is expressed only during the embryo development stage. Dry mature dormant seeds and the seeds germinated for 24 hours, 48 hours, 72 hours, and 96 hours of Glycine max, Vigna radiata and Vigna unguiculata, were investigated for expression of insulin through immunodetection using anti-insulin antibodies. Dry dormant seeds of all the three seeds showed zero expression at 450 nm for insulin, while

Nicotinamide induces differentiation of embryonic stem cells into insulin-secreting cells

International Nuclear Information System (INIS)

Vaca, Pilar; Berna, Genoveva; Araujo, Raquel; Carneiro, Everardo M.; Bedoya, Francisco J.; Soria, Bernat; Martin, Franz

2008-01-01

The poly(ADP-ribose) polymerase (PARP) inhibitor, nicotinamide, induces differentiation and maturation of fetal pancreatic cells. In addition, we have previously reported evidence that nicotinamide increases the insulin content of cells differentiated from embryonic stem (ES) cells, but the possibility of nicotinamide acting as a differentiating agent on its own has never been completely explored. Islet cell differentiation was studied by: (i) X-gal staining after neomycin selection; (ii) BrdU studies; (iii) single and double immunohistochemistry for insulin, C-peptide and Glut-2; (iv) insulin and C-peptide content and secretion assays; and (v) transplantation of differentiated cells, under the kidney capsule, into streptozotocin (STZ)-diabetic mice. Here we show that undifferentiated mouse ES cells treated with nicotinamide: (i) showed an 80% decrease in cell proliferation; (ii) co-expressed insulin, C-peptide and Glut-2; (iii) had values of insulin and C-peptide corresponding to 10% of normal mouse islets; (iv) released insulin and C-peptide in response to stimulatory glucose concentrations; and (v) after transplantation into diabetic mice, normalized blood glucose levels over 7 weeks. Our data indicate that nicotinamide decreases ES cell proliferation and induces differentiation into insulin-secreting cells. Both aspects are very important when thinking about cell therapy for the treatment of diabetes based on ES cells

LEVELS OF NEUROSPECIFIC ENOLASE AND ENOLASE-SPECIFIC AUTOANTIBODIES IN BLOOD SERUM OF THE PATIENTS WITH AUTOIMMUNE THYROPATIES

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N. N. Tsybikov

2010-01-01

Full Text Available The patients with autoimmune thyroiditis and various functional states of thyroid gland, and diffuse toxic goiter with pronounced thyrotoxicosis were studied for neurospecific enolase and enolase-specific autoantibodies levels in blood serum. Increased concentrations of neurospecific enolase and specific autoantibodies were revealed in all groups of the patients. A conclusion was drawn that nervous system may be involved into pathological process during development of thyropaties.

The Analysis of the Value of the Thyroid Autoantibody Measured by Radioimmunoassay

International Nuclear Information System (INIS)

Chung, Jae Hoon; Lee, Myung Shik; Cho, Bo Youn; Lee, Hong Kyu; Koh, Chang Soon; Min, Hun Ki; Lee, Mun Ho

1987-01-01

To evaluate the values of the thyroid autoantibody measured by radioimmunoassay (RIA) and compare it with hemagglutination method (HA) in the normal and the thyroid disease, data were obtained from total 618 persons; 236 healthy persons, 217 patients with Graves disease (including 113 patients with undertreated Graves' disease), 100 Hashimoto's disease, 31 thyroid nodule, and 34 simple goiter. RSR kit made in England was used and could be detected at least 3 U/ml. The positive rates of normal group were antirnicrosomal antibody (AMA) 31.8%, antithyroglobulin antibody (ATA) 44.5% by RIA and there was no considerable change in sex and age distribution. In Graves disease, the positive rates of AMA and ATA were 90.4, 76.9% by RIA, 85, 39% by HA. In Hashimoto's disease, 94,91% by RIA, and 87,48% by HA, respectively. The autoantibody titer by RIA in thyroid autoimmune disease as welt as in normal group was more sensitive than that by HA, especially in ATA. There were linear relationships between the titer of RIA and that of HA in AMA of Graves disease and AMA and ATA of Hashimotos disease. There was no relationship among thyroid autoantibody, free T, index, TBII, and TSH. The titers of AMA and ATA were found to decrease in patients with Graves disease during the course of antithyroid drug therapy. Of the 236 normal subjects, thirty-seven (15.7%) had concentrations of above 7.5 U/ml in AMA, forty-four (18. 6%) above 9 U/ml in ATA. These values were considered as the upper limit for the normal range. In Graves disease, 82,7, 53.8% were above 7.5, 9 U/ml, respectively; In Hashimoto's disease, HZ, 79% were positive. We conclude that RIA was more sensitive than HA in measuring the thyroid autoantibody, but we will study further more for determining the normal range and its interpretation.

Isolation and characterization of an insulin-degrading enzyme from Drosophila melanogaster

International Nuclear Information System (INIS)

Garcia, J.V.; Fenton, B.W.; Rosner, M.R.

1988-01-01

An insulin-degrading enzyme (IDE) from the cytoplasm of Drosophila Kc cells has been purified and characterized. The purified enzyme is a monomer with an s value of 7.2 S, an apparent K/sub m/ for porcine insulin of 3 μM, and a specific activity of 3.3 nmol of porcine insulin degraded/(min x mg). N-Terminal sequence analysis of the gel-purified enzyme gave a single, serine-rich sequence. The Drosophila IDE shares a number of properties in common with its mammalian counterpart. The enzyme could be specifically affinity-labeled with [ 125 I]insulin, has a molecular weight of 110K, and has a pI of 5.3. Although Drosophila Kc cells grow at room temperature, the optimal enzyme activity assay conditions parallel those of the mammalian IDE: 37 0 C and a pH range of 7-8. The Drosophila IDE activity, like the mammalian enzymes, is inhibited by bacitracin and sulfhydryl-specific reagents. Similarly, the Drosophila IDE activity is insensitive to glutathione as well as protease inhibitors such as aprotinin and leupeptin. Insulin-like growth factor II, equine insulin, and porcine insulin compete for degradation of [ 125 I]insulin at comparable concentrations (approximately 10 -6 M), whereas insulin-like growth factor I and the individual A and B chains of insulin are less effective. The high degree of evolutionary conservation between the Drosophila and mammalian IDE suggest an important role for this enzyme in the metabolism of insulin and also provides further evidence for the existence of a complete insulin-like system in invertebrate organisms such as Drosophila

Specificities of anti-neutrophil autoantibodies in patients with rheumatoid arthritis (RA)

DEFF Research Database (Denmark)

Brimnes, J; Halberg, P; Jacobsen, Søren

1997-01-01

The objective of this study was to characterize antigens recognized by neutrophil-specific autoantibodies from patients with RA. Sera from 62 RA patients were screened by indirect immunofluorescence (IIF). Positive sera were further tested by ELISAs for antibodies against various granule proteins...

Insulin-induced enhancement of MCF-7 breast cancer cell response to 5-fluorouracil and cyclophosphamide.

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Agrawal, Siddarth; Łuc, Mateusz; Ziółkowski, Piotr; Agrawal, Anil Kumar; Pielka, Ewa; Walaszek, Kinga; Zduniak, Krzysztof; Woźniak, Marta

2017-06-01

The study was designed to evaluate the potential use of insulin for cancer-specific treatment. Insulin-induced sensitivity of MCF-7 breast cancer cells to chemotherapeutic agents 5-fluorouracil and cyclophosphamide was evaluated. To investigate and establish the possible mechanisms of this phenomenon, we assessed cell proliferation, induction of apoptosis, activation of apoptotic and autophagic pathways, expression of glucose transporters 1 and 3, formation of reactive oxygen species, and wound-healing assay. Additionally, we reviewed the literature regarding theuse of insulin in cancer-specific treatment. We found that insulin increases the cytotoxic effect of 5-fluorouracil and cyclophosphamide in vitro up to two-fold. The effect was linked to enhancement of apoptosis, activation of apoptotic and autophagic pathways, and overexpression of glucose transporters 1 and 3 as well as inhibition of cell proliferation and motility. We propose a model for insulin-induced sensitization process. Insulin acts as a sensitizer of cancer cells to cytotoxic therapy through various mechanisms opening a possibility for metronomic insulin-based treatments.

Plasma autoantibodies against heat shock protein 70, enolase 1 and ribonuclease/angiogenin inhibitor 1 as potential biomarkers for cholangiocarcinoma.

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Rucksak Rucksaken

Full Text Available The diagnosis of cholangiocarcinoma (CCA is often challenging, leading to poor prognosis. CCA arises via chronic inflammation which may be associated with autoantibodies production. This study aims to identify IgG antibodies directed at self-proteins and tumor-associated antigens. Proteins derived from immortalized cholangiocyte cell line (MMNK1 and CCA cell lines (M055, M214 and M139 were separated using 2-dimensional electrophoresis and incubated with pooled plasma of patients with CCA and non-neoplastic controls by immunoblotting. Twenty five immunoreactive spots against all cell lines-derived proteins were observed on stained gels and studied by LC-MS/MS. Among these, heat shock protein 70 (HSP70, enolase 1 (ENO1 and ribonuclease/angiogenin inhibitor 1 (RNH1 obtained the highest matching scores and were thus selected for further validation. Western blot revealed immunoreactivity against HSP70 and RNH1 in the majority of CCA cases and weakly in healthy individuals. Further, ELISA showed that plasma HSP70 autoantibody level in CCA was significantly capable to discriminate CCA from healthy individuals with an area under the receiver operating characteristic curve of 0.9158 (cut-off 0.2630, 93.55% sensitivity and 73.91% specificity. Plasma levels of IgG autoantibodies against HSP70 were correlated with progression from healthy individuals to cholangitis to CCA (r = 0.679, P<0.001. In addition, circulating ENO1 and RNH1 autoantibodies levels were also significantly higher in cholangitis and CCA compared to healthy controls (P<0.05. Moreover, the combinations of HSP70, ENO1 or RNH1 autoantibodies positivity rates improved specificity to over 78%. In conclusion, plasma IgG autoantibodies against HSP70, ENO1 and RNH1 may represent new diagnostic markers for CCA.

Methodological Challenges in Protein Microarray and Immunohistochemistry for the Discovery of Novel Autoantibodies in Paediatric Acute Disseminated Encephalomyelitis

Science.gov (United States)

Peschl, Patrick; Ramberger, Melanie; Höftberger, Romana; Jöhrer, Karin; Baumann, Matthias; Rostásy, Kevin; Reindl, Markus

2017-01-01

Acute disseminated encephalomyelitis (ADEM) is a rare autoimmune-mediated demyelinating disease affecting mainly children and young adults. Differentiation to multiple sclerosis is not always possible, due to overlapping clinical symptoms and recurrent and multiphasic forms. Until now, immunoglobulins reactive to myelin oligodendrocyte glycoprotein (MOG antibodies) have been found in a subset of patients with ADEM. However, there are still patients lacking autoantibodies, necessitating the identification of new autoantibodies as biomarkers in those patients. Therefore, we aimed to identify novel autoantibody targets in ADEM patients. Sixteen ADEM patients (11 seronegative, 5 seropositive for MOG antibodies) were analysed for potential new biomarkers, using a protein microarray and immunohistochemistry on rat brain tissue to identify antibodies against intracellular and surface neuronal and glial antigens. Nine candidate antigens were identified in the protein microarray analysis in at least two patients per group. Immunohistochemistry on rat brain tissue did not reveal new target antigens. Although no new autoantibody targets could be found here, future studies should aim to identify new biomarkers for therapeutic and prognostic purposes. The microarray analysis and immunohistochemistry methods used here have several limitations, which should be considered in future searches for biomarkers. PMID:28327523

Obstetric and vascular APS: same autoantibodies but different diseases?

Science.gov (United States)

Meroni, P L; Raschi, E; Grossi, C; Pregnolato, F; Trespidi, L; Acaia, B; Borghi, M O

2012-06-01

Beta2 glycoprotein I (β2GPI)-dependent antiphospholipid antibodies (aPLs) are the main pathogenic autoantibody population and at the same time the laboratory diagnostic tool for the antiphospholipid syndrome (APS). These antibodies are responsible for both the vascular and the obstetric manifestations of the syndrome but the pathogenic mechanisms behind these manifestations are not the same. For example, thrombotic events do not appear to play a major role in APS miscarriages and a direct reactivity of β2GPI-dependent aPLs on decidual and trophoblast cells was reported. A local expression of β2GPI on these tissues was reported both in physiological conditions and in APS women, thus explaining the local tropism of the autoantibodies. The two hit hypothesis was suggested to explain why the vascular manifestations of APS may occur only occasionally in spite of the persistent presence of aPLs. This is not apparently the case for the obstetric variant of the syndrome, making the difference even more striking. A different pathogenesis may also provide the rationale for the well-known fact that the vascular and the obstetric manifestations may occur independently although in a minority of cases.

Insulin and insulin signaling play a critical role in fat induction of insulin resistance in mouse

Science.gov (United States)

Ning, Jie; Hong, Tao; Yang, Xuefeng; Mei, Shuang; Liu, Zhenqi; Liu, Hui-Yu

2011-01-01

The primary player that induces insulin resistance has not been established. Here, we studied whether or not fat can cause insulin resistance in the presence of insulin deficiency. Our results showed that high-fat diet (HFD) induced insulin resistance in C57BL/6 (B6) mice. The HFD-induced insulin resistance was prevented largely by the streptozotocin (STZ)-induced moderate insulin deficiency. The STZ-induced insulin deficiency prevented the HFD-induced ectopic fat accumulation and oxidative stress in liver and gastrocnemius. The STZ-induced insulin deficiency prevented the HFD- or insulin-induced increase in hepatic expression of long-chain acyl-CoA synthetases (ACSL), which are necessary for fatty acid activation. HFD increased mitochondrial contents of long-chain acyl-CoAs, whereas it decreased mitochondrial ADP/ATP ratio, and these HFD-induced changes were prevented by the STZ-induced insulin deficiency. In cultured hepatocytes, we observed that expressions of ACSL1 and -5 were stimulated by insulin signaling. Results in cultured cells also showed that blunting insulin signaling by the PI3K inhibitor LY-294002 prevented fat accumulation, oxidative stress, and insulin resistance induced by the prolonged exposure to either insulin or oleate plus sera that normally contain insulin. Finally, knockdown of the insulin receptor prevented the oxidative stress and insulin resistance induced by the prolonged exposure to insulin or oleate plus sera. Together, our results show that insulin and insulin signaling are required for fat induction of insulin resistance in mice and cultured mouse hepatocytes. PMID:21586696

Islet autoantibodies and residual beta cell function in type 1 diabetes children followed for 3-6 years

DEFF Research Database (Denmark)

Sørensen, Jesper Sand; Vaziri-Sani, Fariba; Maziarz, M

2012-01-01

To test if islet autoantibodies at diagnosis of type 1 diabetes (T1DM) and after 3-6 years with T1D predict residual beta-cell function (RBF) after 3-6 years with T1D.......To test if islet autoantibodies at diagnosis of type 1 diabetes (T1DM) and after 3-6 years with T1D predict residual beta-cell function (RBF) after 3-6 years with T1D....

Antibodies to the α-subunit of insulin receptor from eggs of immunized hens

International Nuclear Information System (INIS)

Song, C.; Yu, J.; Bai, D.H.; Hester, P.Y.; Kim, K.

1985-01-01

Simple methods for the generation, purification, and assay of antibodies to the α-subunit of insulin receptor from eggs of immunized hen have been described. Chicken antibodies against the α-subunit inhibit insulin binding to the receptor and stimulate glucose oxidation as well as autophosphorylation of the β-subunit. Thus the properties of chicken antibodies are very similar to those of antibodies found in human autoimmune diseases and different from rabbit antibodies obtained against the same antigen

Studies on insulin secretion and insulin resistance in non-insulin-dependent diabetes in young Indians

International Nuclear Information System (INIS)

Naidoo, C.

1986-01-01

Patients with Non-insulin-dependent diabetes mellitus (NIDDM) have defects in insulin secretion and insulin action. In the discrete genetic syndrome of NIDDY (non-insulin-dependent diabetes in the young), the situation is less clear and these aspects is the subject of this thesis. This study included Indian pasients with three generation transmission of NIDDM via one parent. The insulin and C-peptide responses to oral and intravenous glucose in patients with NIDDY were studied. The insulin and glucose responses to non-glucose secretogogues glucagon, tolbutamide and arginine, in NIDDY were also investigated. The following aspects with regard to insulin resistance in NIDDY were examined: glucose and free fatty acid response to intravenous insulin administration, insulin binding to circulating erythrocytes and monocytes, 125 I-insulin binding to the solubilized erythrocyte membrane receptor and 125 I-insulin binding to fibroblasts in culture

Studies on insulin secretion and insulin resistance in non-insulin-dependent diabetes in young Indians

Energy Technology Data Exchange (ETDEWEB)

Naidoo, C

1986-01-01

Patients with Non-insulin-dependent diabetes mellitus (NIDDM) have defects in insulin secretion and insulin action. In the discrete genetic syndrome of NIDDY (non-insulin-dependent diabetes in the young), the situation is less clear and these aspects is the subject of this thesis. This study included Indian pasients with three generation transmission of NIDDM via one parent. The insulin and C-peptide responses to oral and intravenous glucose in patients with NIDDY were studied. The insulin and glucose responses to non-glucose secretogogues glucagon, tolbutamide and arginine, in NIDDY were also investigated. The following aspects with regard to insulin resistance in NIDDY were examined: glucose and free fatty acid response to intravenous insulin administration, insulin binding to circulating erythrocytes and monocytes, /sup 125/I-insulin binding to the solubilized erythrocyte membrane receptor and /sup 125/I-insulin binding to fibroblasts in culture.

Usefulness of antineutrophil cytoplasmic autoantibodies in diagnosing and managing systemic vasculitis

NARCIS (Netherlands)

Kallenberg, Cees G. M.

Purpose of reviewAntineutrophil cytoplasmic autoantibodies (ANCAs) are considered important diagnostic tests in the work-up of patients suspected of vasculitis. Here we discuss new developments in the methodology of testing, the pitfalls in using these tests as diagnostic tools, and the value of

Selenium Supplementation Significantly Reduces Thyroid Autoantibody Levels in Patients with Chronic Autoimmune Thyroiditis

DEFF Research Database (Denmark)

Wichman, Johanna Eva Märta; Winther, Kristian Hillert; Bonnema, Steen Joop

2016-01-01

BACKGROUND: Selenium supplementation may decrease circulating thyroid autoantibodies in patients with chronic autoimmune thyroiditis (AIT), but the available trials are heterogenous. This study expands and critically reappraises the knowledge on this topic. METHODS: A literature search identified...... 3366 records. Controlled trials in adults (≥18 years of age) with AIT, comparing selenium with or without levothyroxine (LT4), versus placebo and/or LT4, were eligible. Assessed outcomes were serum thyroid peroxidase (TPOAb) and thyroglobulin (TgAb) autoantibody levels, and immunomodulatory effects...... and LT4-untreated. Heterogeneity was estimated using I(2), and quality of evidence was assessed per outcome, using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) guidelines. RESULTS: In LT4-treated populations, the selenium group had significantly lower TPOAb levels after...

Degludec insulin: A novel basal insulin

OpenAIRE

Kalra, Sanjay; Unnikrishnan, Ambika Gopalakrishnan; Baruah, Manash; Kalra, Bharti

2011-01-01

This paper reviews a novel insulin analogue, degludec, which has the potential to emerge as an ideal basal insulin. It reviews the limitations of existing basal insulin and analogues, and highlights the need for a newer molecule. The paper discusses the potential advantages of degludec, while reviewing its pharmacologic and clinical studies done so far. The paper assesses the potential role of insulin degludec and degludec plus in clinical diabetes practice.

Idiopathic factor VIII inhibitor autoantibody in a man presented after accident.

NARCIS (Netherlands)

Mansouritorghabeh, H.; Lak, M.; Heerde, W.L. van

2009-01-01

Acquired hemophilia A is a rare but severe autoimmune bleeding disorder caused by autoantibodies against factor VIII activity and is a potentially life-threatening hemorrhagic disorder. The incidence of acquired hemophilia A has been estimated as 1.48 cases per million per year. The overall rate of

Ethanolic Extract of Butea monosperma Leaves Elevate Blood Insulin Level in Type 2 Diabetic Rats, Stimulate Insulin Secretion in Isolated Rat Islets, and Enhance Hepatic Glycogen Formation

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Mehdi Bin Samad

2014-01-01

Full Text Available We measured a vast range of parameters, in an attempt to further elucidate previously claimed antihyperglycemic activity of Butea monosperma. Our study clearly negates the possibility of antidiabetic activity by inhibited gastrointestinal enzyme action or by reduced glucose absorption. Reduction of fasting and postprandial glucose level was reconfirmed (P<0.05. Improved serum lipid profile via reduced low density lipoprotein (LDL, cholesterol, triglycerides (TG, and increased high density lipoprotein (HDL was also reestablished (P<0.05. Significant insulin secretagogue activity of B. monosperma was found in serum insulin assay of B. monosperma treated type 2 diabetic rats (P<0.01. This was further ascertained by our study on insulin secretion on isolated rat islets (P<0.05. Improved sensitivity of glucose was shown by the significant increase in hepatic glycogen deposition (P<0.05. Hence, we concluded that antihyperglycemic activity of B. monosperma was mediated by enhanced insulin secretion and enhanced glycogen formation in the liver.

Prognostic Classification Factors Associated With Development of Multiple Autoantibodies, Dysglycemia, and Type 1 Diabetes?A Recursive Partitioning Analysis

OpenAIRE

Xu, Ping; Krischer, Jeffrey P.

2016-01-01

OBJECTIVE To define prognostic classification factors associated with the progression from single to multiple autoantibodies, multiple autoantibodies to dysglycemia, and dysglycemia to type 1 diabetes onset in relatives of individuals with type 1 diabetes. RESEARCH DESIGN AND METHODS Three distinct cohorts of subjects from the Type 1 Diabetes TrialNet Pathway to Prevention Study were investigated separately. A recursive partitioning analysis (RPA) was used to determine the risk classes. Clini...

Antinuclear human autoantibodies as markers in Nicotiana tabacum pollen tubes

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C. Poggialini

2014-01-01

Full Text Available In the present paper we report on the use of antinuclear human autoantibodies as specific markers in Nicotiana tabacum pollen tubes. The antibodies have been tested by fluorescence techniques using a confocal laser scanning microscope. All the antibodies showed specifc labelling pattern and the results, although preliminary in nature, could open new perspectives of research.

Determination of free insulin-like growth factor-I in human serum

DEFF Research Database (Denmark)

Frystyk, J.; Skjærbæk, C.; Ivarsen, P.

2001-01-01

Two fundamentally different methods are currently used for the determination of free insulin-like growth factor-I (IGF-I): ultrafiltration by centrifugation (UF) and direct immunoradiometric assay (IRMA). The aim was to evaluate a commercial IRMA (DSL, Webster, TX, USA) and to compare it with UF....

Differential aetiology and impact of phosphoinositide 3-kinase (PI3K) and Akt signalling in skeletal muscle on in vivo insulin action

DEFF Research Database (Denmark)

Friedrichsen, Martin; Poulsen, P.; Richter, Erik

2010-01-01

signalling was evaluated at three key levels, i.e. the insulin receptor, IRS-1 and V-akt murine thymoma viral oncogene (Akt) levels, employing kinase assays and phospho-specific western blotting. RESULTS: Proximal insulin signalling was not associated with obesity, age or sex. However, birthweight...... for most measures of insulin signalling activity. Glucose disposal was positively associated with Akt-308 phosphorylation (p

Insulin secretion and insulin action in non-insulin-dependent diabetes mellitus: which defect is primary?

Science.gov (United States)

Reaven, G M

1984-01-01

Defects in both insulin secretion and insulin action exist in patients with non-insulin-dependent diabetes mellitus (NIDDM). The loss of the acute plasma insulin response to intravenous glucose is seen in patients with relatively mild degrees of fasting hyperglycemia, but patients with severe fasting hyperglycemia also demonstrate absolute hypoinsulinemia in response to an oral glucose challenge. In contrast, day-long circulating insulin levels are within normal limits even in severely hyperglycemic patients with NIDDM. The relationship between NIDDM and insulin action in NIDDM is less complex, and is a characteristic feature of the syndrome. This metabolic defect is independent of obesity, and the severity of the resistance to insulin-stimulated glucose uptake increases with magnitude of hyperglycemia. Control of hyperglycemia with exogenous insulin ameliorates the degree of insulin resistance, and reduction of insulin resistance with weight loss in obese patients with NIDDM leads to an enhanced insulin response. Since neither therapeutic intervention is capable of restoring all metabolic abnormalities to normal, these observations do not tell us which of these two defects is primarily responsible for the development of NIDDM. Similarly, the observation that most patients with impaired glucose tolerance are hyperinsulinemic and insulin resistant does not prove that insulin resistance is the primary defect in NIDDM. In conclusion, reduction in both insulin secretion and action is seen in patients with NIDDM, and the relationship between these two metabolic abnormalities is very complex.(ABSTRACT TRUNCATED AT 250 WORDS)

Muller cell-specific autoantibodies in a patient with progressive loss of vision

NARCIS (Netherlands)

Peek, R.; Verbraak, F.; Coevoet, H. M.; Kijlstra, A.

1998-01-01

PURPOSE. To study the specificity of circulating retinal autoantibodies in a patient with progressive loss of vision resembling cancer-associated retinopathy in the absence of systemic malignancy. METHODS. Patient's serum was tested for the presence of antiretinal antibodies by Western blot

Results of a comparative study on insulin radioimmunoassay in 36 Italian laboratories

Energy Technology Data Exchange (ETDEWEB)

Costantini, A; Lostia, O; Malvano, R; Rolleri, E; Taggi, F; Zucchelli, G C [Istituto Superiore di Sanita, Rome (Italy); Consiglio Nazionale delle Ricerche, Pisa (Italy))

1975-12-01

An interlaboratory study in which the insulin contents of five plasma samples were estimated in 36 italian laboratories was coordinated by the Istituto Superiore di Sanita (National Institute of Health) and the Consiglio Nazionale delle Ricerche (National Research Council). A rather large between-laboratory variability resulted, though the ranking of samples according to their insulin concentrations was practically the same. A significant dependence of estimates on the method used was established. The analysis of data aimed at defining the possible reasons of the assay variability is reported and discussed.

The Role of GAD65 Autoantibody in Diabetes Mellitus and their First-Degree Relatives and Comparison with Healthy Persons

Directory of Open Access Journals (Sweden)

M Nakhjavani

2001-06-01

Full Text Available The diabetes is an autoimmune disease, in which the role of autoantibodies is of a specific importance. The appearance of these autoantibodies can be the first symptom in the serum of type I diabetic patients, which may appear ten years before onset of the disease. The most important autoantibodies include Glutamic acid decarboxylase autoantibodies (GAD65-Ab. This can be used as a good tool for prediction in screening tests in type I diabetic patients. In the present study with prosedure RIA, we investigated the level of GAD65-Ab in patients with diabetes type I and their close relatives, and compared them with healthy persons. From the type I diabetic patients who have been suffering from the disease for periods of one week to twenty years, 63.3% of them had positive Anti-GAD65. This ratio was 8% in their close trelatives, and 0% in healthy persons. The difference in Anti-GAD65 between the healthy persons and close relative of patients was significant. This test may be employed in diabetes type I, as a screening test, and confirms the results of studies which have been conducted so far outside this country.

Major antigen of liver kidney microsomal autoantibodies in idiopathic autoimmune hepatitis is cytochrome P450db1.

OpenAIRE

Manns, M P; Johnson, E F; Griffin, K J; Tan, E M; Sullivan, K F

1989-01-01

Type 1, liver kidney microsomal autoantibodies (LKM-1) are associated with a subgroup of idiopathic autoimmune type, chronic active hepatitis (CAH). The antigenic specificity of LKM-1 autoantibodies from 13 patients was investigated by immunoblot analysis of human liver microsomal proteins. Polypeptides of 50, 55, and 64 kD were detected with these antisera. A high titer LKM-1 serum was selected to screen a human liver lambda gt11 cDNA expression library, resulting in the isolation of several...

β2-glycoprotein-1 autoantibodies from patients with antiphospholipid syndrome are sufficient to potentiate arterial thrombus formation in a mouse model

Science.gov (United States)

Arad, Ariela; Proulle, Valerie; Furie, Richard A.; Furie, Barbara C.

2011-01-01

Antiphospholipid syndrome is characterized by thrombosis, recurrent fetal loss, and the presence of the lupus anticoagulant, anticardiolipin antibodies, or anti–β2-glycoprotein-1 (anti–β2-GP1) antibodies. Although anti–β2-GP1 antibodies have been documented as a biomarker for diagnosis of antiphospholipid syndrome, their direct role in the pathogenesis of thrombosis is unknown. We have demonstrated using intravital microscopy that anti–β2-GP1 autoantibodies purified from the sera of patients with antiphospholipid syndrome complicated by thrombosis greatly amplify thrombus size after laser-induced vessel wall injury in live mice. Anti–β2-GP1 autoantibodies from 3 patients with antiphospholipid syndrome were affinity-purified using human β2-GP1 bound to agarose. The effects of purified anti–β2-GP1 IgG autoantibodies, of anti–β2-GP1–depleted IgG, and of IgG from normal human sera on thrombus formation were measured in mice after arterial injury in the cremaster muscle. Before injury, purified anti–β2-GP1 IgG autoantibodies, anti–β2-GP1 antibody–depleted IgG, or IgG from normal human sera were infused. Increasing amounts of purified anti–β2-GP1 autoantibodies increased thrombus size in a dose-dependent manner, whereas neither anti–β2-GP1 antibody-depleted IgG nor IgG from normal serum affected thrombus size. These results indicate that anti–β2-GP1 IgG autoantibodies in antiphospholipid syndrome patient sera are not only a marker of antiphospholipid syndrome but are directly involved in the pathogenesis of thrombosis. PMID:21245481

Regulation of dendritic cell function by insulin/IGF-1/PI3K/Akt signaling through klotho expression.

Science.gov (United States)

Xuan, Nguyen Thi; Hoang, Nguyen Huy; Nhung, Vu Phuong; Duong, Nguyen Thuy; Ha, Nguyen Hai; Hai, Nong Van

2017-06-01

Insulin or insulin-like growth factor 1 (IGF-1) promotes the activation of phosphoinositide 3 kinase (PI3K)/Akt signaling in immune cells including dendritic cells (DCs), the most potent professional antigen-presenting cells for naive T cells. Klotho, an anti-aging protein, participates in the regulation of the PI3K/Akt signaling, thus the Ca 2+ -dependent migration is reduced in klotho-deficient DCs. The present study explored the effects of insulin/IGF-1 on DC function through klotho expression. To this end, the mouse bone marrow cells were isolated and cultured with GM-CSF to attain bone marrow-derived DCs (BMDCs). Cells were treated with insulin or IGF-1 and followed by stimulating with lipopolysaccharides (LPS). Tumor necrosis factor (TNF)-α formation was examined by enzyme-linked immunosorbent assay (ELISA). Phagocytosis was analyzed by FITC-dextran uptake assay. The expression of klotho was determined by quantitative PCR, immunoprecipitation and western blotting. As a result, treatment of the cells with insulin/IGF-1 resulted in reducing the klotho expression as well as LPS-stimulated TNF-α release and increasing the FITC-dextran uptake but unaltering reactive oxygen species (ROS) production in BMDCs. The effects were abolished by using pharmacological inhibition of PI3K/Akt with LY294002 and paralleled by transfecting DCs with klotho siRNA. In conclusion, the regulation of klotho sensitive DC function by IGF-1 or insulin is mediated through PI3K/Akt signaling pathway in BMDCs.

Insulin degludec versus insulin glargine in insulin-naive patients with type 2 diabetes

DEFF Research Database (Denmark)

Zinman, Bernard; Philis-Tsimikas, Athena; Cariou, Bertrand

2012-01-01

To compare ultra-long-acting insulin degludec with glargine for efficacy and safety in insulin-naive patients with type 2 diabetes inadequately controlled with oral antidiabetic drugs (OADs).......To compare ultra-long-acting insulin degludec with glargine for efficacy and safety in insulin-naive patients with type 2 diabetes inadequately controlled with oral antidiabetic drugs (OADs)....

Infectious Mononucleosis Triggers Generation of IgG Auto-Antibodies against Native Myelin Oligodendrocyte Glycoprotein.

Science.gov (United States)

Kakalacheva, Kristina; Regenass, Stephan; Wiesmayr, Silke; Azzi, Tarik; Berger, Christoph; Dale, Russell C; Brilot, Fabienne; Münz, Christian; Rostasy, Kevin; Nadal, David; Lünemann, Jan D

2016-02-12

A history of infectious mononucleosis (IM), symptomatic primary infection with the Epstein Barr virus, is associated with the development of autoimmune diseases and increases the risk to develop multiple sclerosis. Here, we hypothesized that immune activation during IM triggers autoreactive immune responses. Antibody responses towards cellular antigens using a HEp-2 based indirect immunofluorescence assay and native myelin oligodendrocyte glycoprotein (MOG) using a flow cytometry-based assay were determined in 35 patients with IM and in 23 control subjects. We detected frequent immunoglobulin M (IgM) reactivity to vimentin, a major constituent of the intermediate filament family of proteins, in IM patients (27/35; 77%) but rarely in control subjects (2/23; 9%). IgG autoantibodies binding to HEp-2 cells were absent in both groups. In contrast, IgG responses to native MOG, present in up to 40% of children with inflammatory demyelinating diseases of the central nervous system (CNS), were detectable in 7/35 (20%) patients with IM but not in control subjects. Normalization of anti-vimentin IgM levels to increased total IgM concentrations during IM resulted in loss of significant differences for anti-vimentin IgM titers. Anti-MOG specific IgG responses were still detectable in a subset of three out of 35 patients with IM (9%), even after normalization to increased total IgG levels. Vimentin-specific IgM and MOG-specific IgG responses decreased following clinical resolution of acute IM symptoms. We conclude from our data that MOG-specific memory B cells are activated in subset of patients with IM.

Dynamic changes and clinical significance of thyroid auto-antibodies before and after radioiodine treatment for Graves' disease

International Nuclear Information System (INIS)

Zhao Zhiying; Zhu Li; Wang Zhenghua

2005-01-01

To study the changes and their clinical effect of serum levels of thyroid globulin auto-antibodies (TGAb), thyroid peroxidase auto-antibodies (TPOAb) during radioiodine treatment of Graves' disease, and to investigate early therapeutic effect of radioiodine and influence factors for early hypothyroidism, 334 patients were divided into a positive group (TGAb>115IU/mL, TPOAb>34IU/mL) and a negative group (TGAb 131 I treatment. The levels of FT 3 , FT 4 , TSH, TGAb and TPOAb in serum were measured before 131 I therapy and at the 3rd, 6th, 9th, 12th month after the treatment respectively. Within one year after radioiodine treatment, 23.8% patients (48 out of 202) in the positive group and 11.4% (15 out of 132) in the negative group suffered from early hypothyroidism (P 131 I could reduce the level of thyroid auto-antibodies and promote the improvement and recovery of autoimmunity status. (authors)

Natural (auto)antibodies in calves are affected by age and diet

NARCIS (Netherlands)

Khobondo, J.O.; Nieuwland, M.G.B.; Webb, L.E.; Bokkers, E.A.M.; Parmentier, H.K.

2015-01-01

Background: Natural autoantibodies (N(a)ab) were found in every species tested so far, and are likely important in maintaining homeostasis. Objectives: (1) To determine N(a)ab in Bos taurus calves, (2) evaluate effects of diet and age on N(a)ab binding repertoires in calves, and (3) delineate bovine

Analysis of IRS-1-mediated phosphatidylinositol 3-kinase activation in the adipose tissue of polycystic ovary syndrome patients complicated with insulin resistance

Energy Technology Data Exchange (ETDEWEB)

Yongli, Chu [Yantai Yuhuangding Hospital, Yantai (China). Dept. of Obstetrics and Gynecology; Hongyu, Qiu; Yongyu, Sun; Min, Li; Hongfa, Li

2004-04-01

Objective: To investigate the insulin receptor substance-1 (IRS-1)-mediated phosphatidylinositol-3 (PI-3) kinase activity in adipose tissue of polycystic ovary syndrome (PCOS) patients, and to explore molecular mechanisms of insulin resistance of PCOS. Methods: Blood and adipose tissue samples from patients with PCOS with insulin resistance (n=19), PCOS without insulin resistance (n=10) and controls (n=15) were collected. Serum luteinizing hormone (LH), follicle stimulating hormone (FSH), testosterone (T) were measured by chemiluminescence assay. Fasting insulin (FIN) was measured by radioimmunoassay. Fasting plasma glucose (FPG) was measured by oxidase assay. Insulin resistance index (IR) was calculated using homeostasis model assessment (HOMA) to analyze the relationship between these markers and insulin resistance. The tyrosine phosphorylation of IRS-1 was measured by immunoprecipitation and enhanced chemiluminescent immunoblotting technique. PI-3 kinase activity was detected by immunoprecipitation, thin-layer chromatography and gamma scintillation counting. The results were analyzed by statistical methods. Results: 1) The levels of serum LH, LH/FSH, T, FIN and HOMA-IR in PCOS without insulin resistance were significantly higher than those of control group (all P<0.05); the levels of serum LH, LH/FSH, T, FIN and HOMA-IR in PCOS with insulin resistance were significantly higher than those of PCOS without insulin resistance (all P<0.05). 2) The tyrosine phosphorylation analysis of IRS-1 showed that IRS-1 tyrosine phosphorylation was significantly decreased in PCOS with insulin resistance compared to that of PCOS without insulin resistance and control groups (P<0.01). 3) PI-3 kinase activity was significantly decreased (P<0.01) and negatively correlated with HOMA-IR. Conclusion: In consequence of the weaker signal caused by the change of upper stream signal molecule IRS-1 tyrosine phosphorylation, PI-3 kinase activity decreased, it affects the insulin signal

Analysis of IRS-1-mediated phosphatidylinositol 3-kinase activation in the adipose tissue of polycystic ovary syndrome patients complicated with insulin resistance

International Nuclear Information System (INIS)

Chu Yongli; Qiu Hongyu; Sun Yongyu; Li Min; Li Hongfa

2004-01-01

Objective: To investigate the insulin receptor substance-1 (IRS-1)-mediated phosphatidylinositol-3 (PI-3) kinase activity in adipose tissue of polycystic ovary syndrome (PCOS) patients, and to explore molecular mechanisms of insulin resistance of PCOS. Methods: Blood and adipose tissue samples from patients with PCOS with insulin resistance (n=19), PCOS without insulin resistance (n=10) and controls (n=15) were collected. Serum luteinizing hormone (LH), follicle stimulating hormone (FSH), testosterone (T) were measured by chemiluminescence assay. Fasting insulin (FIN) was measured by radioimmunoassay. Fasting plasma glucose (FPG) was measured by oxidase assay. Insulin resistance index (IR) was calculated using homeostasis model assessment (HOMA) to analyze the relationship between these markers and insulin resistance. The tyrosine phosphorylation of IRS-1 was measured by immunoprecipitation and enhanced chemiluminescent immunoblotting technique. PI-3 kinase activity was detected by immunoprecipitation, thin-layer chromatography and gamma scintillation counting. The results were analyzed by statistical methods. Results: 1) The levels of serum LH, LH/FSH, T, FIN and HOMA-IR in PCOS without insulin resistance were significantly higher than those of control group (all P<0.05); the levels of serum LH, LH/FSH, T, FIN and HOMA-IR in PCOS with insulin resistance were significantly higher than those of PCOS without insulin resistance (all P<0.05). 2) The tyrosine phosphorylation analysis of IRS-1 showed that IRS-1 tyrosine phosphorylation was significantly decreased in PCOS with insulin resistance compared to that of PCOS without insulin resistance and control groups (P<0.01). 3) PI-3 kinase activity was significantly decreased (P<0.01) and negatively correlated with HOMA-IR. Conclusion: In consequence of the weaker signal caused by the change of upper stream signal molecule IRS-1 tyrosine phosphorylation, PI-3 kinase activity decreased, it affects the insulin signal

Colostrum of Healthy Mothers Contains Broad Spectrum of Secretory IgA Autoantibodies

Czech Academy of Sciences Publication Activity Database

Přibylová, Jaroslava; Krausová, Klára; Kocourková, I.; Rossmann, Pavel; Klimešová, Klára; Kverka, Miloslav; Tlaskalová-Hogenová, Helena

2012-01-01

Roč. 32, č. 6 (2012), s. 1372-1380 ISSN 0271-9142 R&D Projects: GA ČR(CZ) GAP304/11/1252 Institutional support: RVO:61388971 Keywords : Autoantibodies * mucosal immunity * immunoglobulins Subject RIV: EC - Immunology Impact factor: 3.382, year: 2012

Fibrillization kinetics of insulin solution in an interfacial shearing flow

Science.gov (United States)

Balaraj, Vignesh; McBride, Samantha; Hirsa, Amir; Lopez, Juan

2015-11-01

Although the association of fibril plaques with neurodegenerative diseases like Alzheimer's and Parkinson's is well established, in-depth understanding of the roles played by various physical factors in seeding and growth of fibrils is far from well known. Of the numerous factors affecting this complex phenomenon, the effect of fluid flow and shear at interfaces is paramount as it is ubiquitous and the most varying factor in vivo. Many amyloidogenic proteins have been found to denature upon contact at hydrophobic interfaces due to the self-assembling nature of protein in its monomeric state. Here, fibrillization kinetics of insulin solution is studied in an interfacial shearing flow. The transient surface rheological response of the insulin solution to the flow and its effect on the bulk fibrillization process has been quantified. Minute differences in hydrophobic characteristics between two variants of insulin- Human recombinant and Bovine insulin are found to result in very different responses. Results presented will be in the form of fibrillization assays, images of fibril plaques formed, and changes in surface rheological properties of the insulin solution. The interfacial velocity field, measured from images (via Brewster Angle Microscopy), is compared with computations. Supported by NNX13AQ22G, National Aeronautics and Space Administration.

The Role of Insulin, Insulin Growth Factor, and Insulin-Degrading Enzyme in Brain Aging and Alzheimer's Disease

OpenAIRE

Messier, Claude; Teutenberg, Kevin

2005-01-01

Most brain insulin comes from the pancreas and is taken up by the brain by what appears to be a receptor-based carrier. Type 2 diabetes animal models associated with insulin resistance show reduced insulin brain uptake and content. Recent data point to changes in the insulin receptor cascade in obesity-related insulin resistance, suggesting that brain insulin receptors also become less sensitive to insulin, which could reduce synaptic plasticity. Insulin transport to the brain is reduced in a...

Neuromyelitis optica in a young child with positive serum autoantibody

OpenAIRE

Loma, Ingrid P.; Asato, Miya R.; Filipink, Robyn A.; Alper, Gulay

2008-01-01

Relapsing neuromyelitis optica is rare in children. The identification of highly specific serum autoantibody marker (neuromyelitis optica –immunoglobulin G) differentiates neuromyelitis optica from other demyelinating disorders particularly in clinically challenging cases. We present a child with multiple episodes of transverse myelitis and optic neuritis with positive neuromyelitis optica-immunoglobulin G titers consistent with a diagnosis of relapsing neuromyelitis optica. Serial titers of ...

Development of autoantibodies in the TrialNet Natural History Study.

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Vehik, Kendra; Beam, Craig A; Mahon, Jeffrey L; Schatz, Desmond A; Haller, Michael J; Sosenko, Jay M; Skyler, Jay S; Krischer, Jeffrey P

2011-09-01

Understanding the relationship between age and islet autoantibody (Ab) seroconversion can establish the optimal screening interval(s) to assess risk for type 1 diabetes, identify subjects who can participate in prevention trials, and determine associated costs. This study assessed the rates of seroconversion to glutamic acid decarboxylase positive (GAD65(+)), insulin positive (mIAA(+)), and insulinoma-associated protein 2 positive (ICA512(+)) in a large cohort of relatives of type 1 diabetes probands undergoing Ab rescreening in the TrialNet Natural History Study. Of 32,845 children aged <18 years screened for Abs, 1,287 (3.9%) were GAD65(+), 778 (2.4%) were mIAA(+), 677 (2.1%) were ICA512(+), and 31,038 were Ab-negative. Ab-negative children were offered annual rescreening up to 18 years of age. Cox regression was used to estimate the risk for GAD65, mIAA, and ICA512 seroconversion. RESULTS There were 205 children who seroconverted to GAD65(+), 155 who seroconverted to mIAA(+), and 53 who seroconverted to ICA512(+) over 5.8 years of follow-up. The risk of mIAA (hazard ratio 0.89 [95% CI 0.85-0.92]) and GAD65 (0.96 [0.93-0.99]) seroconversion significantly decreased with increasing age (i.e., for each 1-year increase in age, the risk of seroconversion decreased by 11% [P < 0.0001] for mIAA and 4% [P = 0.04] for GAD65) across all ages. The cumulative Ab seroconversion was 2% for those <10 years of age versus 0.7% for those ≥10 years of age. The risk of development of islet Abs declines with increasing age in type 1 diabetes relatives. These data support annual screening for children <10 years of age and one additional screening in adolescence.

Insulin radioimmunoassay kit (125I) using polyethyleneglycol (PEG) and a double antibody separation method

International Nuclear Information System (INIS)

Borza, Virginia; Chariton, Delfina; Neacsu, Elena

1997-01-01

Insulin is a polypeptide hormone formed from proinsulin in the b-cells of the islets of Langerhans in the pancreas. It has a widespread effect on carbohydrate, lipid and protein metabolism. Diabetes mellitus is the result of an insulin deficiency brought about either by insufficient insulin secretion or by rapid insulin catabolism. The determination of the insulin level is important for differential etiologic diagnosis and subsequent therapy and prognosis. Insulin radioimmunoassay kit provides a sensitive, precise and specific assay for insulin concentration in serum. Standard and insulin in the patient sample compete with tracer for binding sites on an insulin antibody. The antigen-antibody combination, which forms during incubation time, will be separated from free insulin by different methods. The separation technique using the double antibody technique combined with Polyethyleneglycol (PEG) is presented. The results are compared with the separation method using PEG alone and with double antibody technique. Antiserum to insulin was produced in rats immunized with porcine insulin, while rabbits immunized with rat-g globulin were used as a source for the second antibody.The tested PEG was PEG 6000. The best results were obtained using the double antibody at a 1/50 dilution combined with 7.5 PEG solutions. The time for precipitating the antibody bound fraction by this technique was established to be 30 minutes. The results obtained using this method as separation technique for insulin - antibody complex were better than those obtained using the double antibody techniques or PEG as precipitating agent alone. (authors)

Prognostic Classification Factors Associated With Development of Multiple Autoantibodies, Dysglycemia, and Type 1 Diabetes-A Recursive Partitioning Analysis.

Science.gov (United States)

Xu, Ping; Krischer, Jeffrey P

2016-06-01

To define prognostic classification factors associated with the progression from single to multiple autoantibodies, multiple autoantibodies to dysglycemia, and dysglycemia to type 1 diabetes onset in relatives of individuals with type 1 diabetes. Three distinct cohorts of subjects from the Type 1 Diabetes TrialNet Pathway to Prevention Study were investigated separately. A recursive partitioning analysis (RPA) was used to determine the risk classes. Clinical characteristics, including genotype, antibody titers, and metabolic markers were analyzed. Age and GAD65 autoantibody (GAD65Ab) titers defined three risk classes for progression from single to multiple autoantibodies. The 5-year risk was 11% for those subjects >16 years of age with low GAD65Ab titers, 29% for those ≤16 years of age with low GAD65Ab titers, and 45% for those subjects with high GAD65Ab titers regardless of age. Progression to dysglycemia was associated with islet antigen 2 Ab titers, and 2-h glucose and fasting C-peptide levels. The 5-year risk is 28%, 39%, and 51% for respective risk classes defined by the three predictors. Progression to type 1 diabetes was associated with the number of positive autoantibodies, peak C-peptide level, HbA1c level, and age. Four risk classes defined by RPA had a 5-year risk of 9%, 33%, 62%, and 80%, respectively. The use of RPA offered a new classification approach that could predict the timing of transitions from one preclinical stage to the next in the development of type 1 diabetes. Using these RPA classes, new prevention techniques can be tailored based on the individual prognostic risk characteristics at different preclinical stages. © 2016 by the American Diabetes Association. Readers may use this article as long as the work is properly cited, the use is educational and not for profit, and the work is not altered.

Prognostic Classification Factors Associated With Development of Multiple Autoantibodies, Dysglycemia, and Type 1 Diabetes—A Recursive Partitioning Analysis

Science.gov (United States)

Krischer, Jeffrey P.

2016-01-01

OBJECTIVE To define prognostic classification factors associated with the progression from single to multiple autoantibodies, multiple autoantibodies to dysglycemia, and dysglycemia to type 1 diabetes onset in relatives of individuals with type 1 diabetes. RESEARCH DESIGN AND METHODS Three distinct cohorts of subjects from the Type 1 Diabetes TrialNet Pathway to Prevention Study were investigated separately. A recursive partitioning analysis (RPA) was used to determine the risk classes. Clinical characteristics, including genotype, antibody titers, and metabolic markers were analyzed. RESULTS Age and GAD65 autoantibody (GAD65Ab) titers defined three risk classes for progression from single to multiple autoantibodies. The 5-year risk was 11% for those subjects >16 years of age with low GAD65Ab titers, 29% for those ≤16 years of age with low GAD65Ab titers, and 45% for those subjects with high GAD65Ab titers regardless of age. Progression to dysglycemia was associated with islet antigen 2 Ab titers, and 2-h glucose and fasting C-peptide levels. The 5-year risk is 28%, 39%, and 51% for respective risk classes defined by the three predictors. Progression to type 1 diabetes was associated with the number of positive autoantibodies, peak C-peptide level, HbA1c level, and age. Four risk classes defined by RPA had a 5-year risk of 9%, 33%, 62%, and 80%, respectively. CONCLUSIONS The use of RPA offered a new classification approach that could predict the timing of transitions from one preclinical stage to the next in the development of type 1 diabetes. Using these RPA classes, new prevention techniques can be tailored based on the individual prognostic risk characteristics at different preclinical stages. PMID:27208341

Hepatitis C virus E2 protein involve in insulin resistance through an impairment of Akt/PKB and GSK3β signaling in hepatocytes

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Hsieh Ming-Ju

2012-06-01

Full Text Available Abstract Background Hepatitis C virus (HCV infection may cause liver diseases of various severities ranging from primary acute infection to life-threatening diseases, such as cirrhosis or hepatocellular carcinoma with poor prognosis. According to clinical findings, HCV infection may also lead to some extra-hepatic symptoms, including type 2 diabetes mellitus (DM. Since insulin resistance is the major etiology for type 2 DM and numerous evidences showed that HCV infection associated with insulin resistance, the involvement of E2 in the pathogenesis of type 2 DM and underlying mechanisms were investigated in this study. Methods Reverse transcription and real-time PCR, Western blot assay, Immunoprecipitation, Glucose uptake assay and analysis of cellular glycogen content. Results Results showed that E2 influenced on protein levels of insulin receptor substrate-1 (IRS-1 and impaired insulin-induced Ser308 phosphorylation of Akt/PKB and Ser9 phosphorylation of GSK3β in Huh7 cells, leading to an inhibition of glucose uptake and glycogen synthesis, respectively, and eventually insulin resistance. Conclusions Therefore, HCV E2 protein indeed involved in the pathogenesis of type 2 DM by inducing insulin resistance.

Ultramicromethod of immunreactive insulin determination

International Nuclear Information System (INIS)

Tyrkolev, N.

1979-01-01

A radioimmunologic method of immunoreactive insulin (IRI) determination, requiring 0,02 ml biologic fluid for a single determination, is described. The basic method used in this study, is the thoroughly investigated and for many years applied by the author coal dextran method of IRI determination. The reagents, the scheme of practical performance of the test and calculation of the results are described, and an exemplary standard curve presented. A trial of the method was attempted by comparing the results by the standard and the ultramicromethod. The differences were statistically insignificant. The data of the standard curves of these experiments were also statistically processed. Fifty two sera with different insulin levels (9-275μU/ml) were subjected to comparative IRI assay by either method. They were spanned according to their IRI content, with calculations of the differences between the two methods in the different age groups. A diagram of a single glucose leading (n equals 4) by the two methods is presented. The practical identity of the results obtained by the two methods and the advantages of the ultramicromethod are emphasized. (author)

Self-assembled lecithin/chitosan nanoparticles for oral insulin delivery: preparation and functional evaluation

Science.gov (United States)

Liu, Liyao; Zhou, Cuiping; Xia, Xuejun; Liu, Yuling

2016-01-01

Purpose Here, we investigated the formation and functional properties of self-assembled lecithin/chitosan nanoparticles (L/C NPs) loaded with insulin following insulin–phospholipid complex preparation, with the aim of developing a method for oral insulin delivery. Methods Using a modified solvent-injection method, insulin-loaded L/C NPs were obtained by combining insulin–phospholipid complexes with L/C NPs. The nanoparticle size distribution was determined by dynamic light scattering, and morphologies were analyzed by cryogenic transmission electron microscopy. Fourier transform infrared spectroscopy analysis was used to disclose the molecular mechanism of prepared insulin-loaded L/C NPs. Fast ultrafiltration and a reversed-phase high-performance liquid chromatography assay were used to separate free insulin from insulin entrapped in the L/C NPs, as well as to measure the insulin-entrapment and drug-loading efficiencies. The in vitro release profile was obtained, and in vivo hypoglycemic effects were evaluated in streptozotocin-induced diabetic rats. Results Our results indicated that insulin-containing L/C NPs had a mean size of 180 nm, an insulin-entrapment efficiency of 94%, and an insulin-loading efficiency of 4.5%. Cryogenic transmission electron microscopy observations of insulin-loaded L/C NPs revealed multilamellar structures with a hollow core, encircled by several bilayers. In vitro analysis revealed that insulin release from L/C NPs depended on the L/C ratio. Insulin-loaded L/C NPs orally administered to streptozotocin-induced diabetic rats exerted a significant hypoglycemic effect. The relative pharmacological bioavailability following oral administration of L/C NPs was 6.01%. Conclusion With the aid of phospholipid-complexation techniques, some hydrophilic peptides, such as insulin, can be successfully entrapped into L/C NPs, which could improve oral bioavailability, time-dependent release, and therapeutic activity. PMID:26966360

Determination of auto-antibodies to native and oxidized low-density lipoproteins (LDL) in serum of patients underwent coronariography in the Medical-Surgical Research Center (MSRC)

International Nuclear Information System (INIS)

Conde CerdeiraI, Hector; Soto Lopez, Yosdel; Aroche Aportela, Ronald

2010-01-01

Low-density lipoprotein (LDL) oxidation is an important event in atherosclerosis development. The relationship between oxidized LDL (oxLDL) autoantibodies and coronary artery disease (CAD) remains controversial. IgM and IgG autoantibodies to oxLDL were measured in twenty patients undergoing clinically indicated coronary angiography, and in ten young healthy volunteers from the Center of Molecular Immunology. The levels of IgM autoantibodies to oxLDL did not differ between no CAD patients and healthy subjects, but the levels of IgM autoantibodies to oxLDL of these two groups were higher compared with the one of CAD patient group. Our results, although preliminary, supports the hypothesis that this kind of Abs might be inversely associated with the presence of atherosclerosis

Insulin resistance in women's health: why it matters and how to identify it.

Science.gov (United States)

Legro, Richard S

2009-08-01

To examine the significance of insulin resistance in women's health and review methods for diagnosing it. Clinical phenotypes in conjunction with standard clinical biochemical assays, that is, the metabolic syndrome, remain the key method to diagnose insulin resistance in clinical practice. Candidate alleles from type 2 diabetes offer little predictive value for cardiovascular events beyond traditional risk factors. Simple environmental factors such as irregular meal frequency appear to increase the risk of the metabolic syndrome and require greater scrutiny. Pregnancy complications, particularly gestational diabetes and preeclampsia in the mother and preterm birth in the fetus are events that suggest elevated risk for future cardiovascular morbidity in those affected. Clinical phenotypes of insulin resistance identify women at risk for perinatal and reproductive complications.

Comparison of Two Assays to Determine Anti-Citrullinated Peptide Antibodies in Rheumatoid Arthritis in relation to Other Chronic Inflammatory Rheumatic Diseases: Assaying Anti-Modified Citrullinated Vimentin Antibodies Adds Value to Second-Generation Anti-Citrullinated Cyclic Peptides Testing

Directory of Open Access Journals (Sweden)

Miriam Lizette Díaz-Toscano

2014-01-01

Full Text Available Determination of anti-citrullinated peptide antibodies (ACPA plays a relevant role in the diagnosis of rheumatoid arthritis (RA. To date, it is still unclear if the use of several tests for these autoantibodies in the same patient offers additional value as compared to performing only one test. Therefore, we evaluated the performance of using two assays for ACPA: second-generation anti-citrullinated cyclic peptides antibodies (anti-CCP2 and anti-mutated citrullinated vimentin (anti-MCV antibodies for the diagnosis of RA. We compared three groups: RA (n=142, chronic inflammatory disease (CIRD, n=86, and clinically healthy subjects (CHS, n=56 to evaluate sensitivity, specificity, predictive values, and likelihood ratios (LR of these two assays for the presence of RA. A lower frequency of positivity for anti-CCP2 was found in RA (66.2% as compared with anti-MCV (81.0%. When comparing RA versus other CIRD, sensitivity increased when both assays were performed. This strategy of testing both assays had high specificity and LR+. We conclude that adding the assay of anti-MCV antibodies to the determination of anti-CCP2 increases the sensitivity for detecting seropositive RA. Therefore, we propose the use of both assays in the initial screening of RA in longitudinal studies, including early onset of undifferentiated arthritis.

Autoantibodies to the Rpp25 component of the Th/To complex are the most common antibodies in patients with systemic sclerosis without antibodies detectable by widely available commercial tests.

Science.gov (United States)

Mahler, Michael; Satoh, Minoru; Hudson, Marie; Baron, Murray; Chan, Jason Y F; Chan, Edward K L; Wick, James; Fritzler, Marvin J

2014-07-01

Antinuclear antibodies (ANA) occur in up to 95% of patients with systemic sclerosis (SSc). In most, SSc-associated antibodies are detected (i.e., centromere, topoisomerase I, RNA polymerase III, PM/Scl, Ro52/TRIM21, and U1RNP). Ribonuclease P protein subunit p25, (Rpp25) is an autoantigenic component of the Th/To complex. The contribution of anti-Th/To and anti-Rpp25 antibodies to ANA positivity in patients with SSc remains unknown. Sera from 873 patients with SSc were tested for ANA, and SSc-associated antibodies were measured. Samples without antibodies to extractable nuclear antigens (ENA; n = 53, ANA+/ENA-), were analyzed by immunoprecipitation (IP) and metabolically labeled proteins and for anti-Rpp25 antibodies (n = 50) by a chemiluminescent immunoassay (CLIA) and Rpp25 ELISA. Anti-Th/To antibodies occurred in 19/53 (36%), as determined by IP, and were the most common autoantibody in ANA+/ENA- SSc. Of those samples, 50/53 were available for additional testing by CLIA and ELISA. Anti-Rpp25 antibodies were detected in 12 (24% CLIA) or 10 (20% ELISA) of 50 patients. Receiver-operating characteristic curve analysis showed similar discrimination between Th/To IP-positive (n = 19) and -negative samples (n = 31) by CLIA and ELISA (area under the curve 0.90 vs 0.87; p = 0.6691). The positive percent agreement between IP and CLIA or ELISA was 12/19 (63.2%, 95% CI 38.4-83.7%) or 10/19 (52.6%, 95% CI 73.3-94.2%), respectively. Negative percent agreement was 100% for both assays. Autoantibodies to the Th/To autoantigen are important in patients with SSc who have been considered negative for SSc-specific or SSc-associated antibodies by widely available commercial assays. Rpp25 can be considered a major target of anti-Th/To antibodies. Assays detecting anti-Th/To and anti-Rpp25 antibodies may be important in SSc.

Catalytic activity of autoantibodies toward myelin basic protein correlates with the scores on the multiple sclerosis expanded disability status scale.

Science.gov (United States)

Ponomarenko, Natalia A; Durova, Oxana M; Vorobiev, Ivan I; Belogurov, Alexey A; Telegin, Georgy B; Suchkov, Sergey V; Misikov, Victor K; Morse, Herbert C; Gabibov, Alexander G

2006-02-28

Autoantibodies toward myelin basic protein (MBP) evidently emerge in sera and cerebrospinal fluid of the patients with multiple sclerosis (MS), as well as in a MS rodent model, i.e., experimental autoimmune encephalomyelitis (EAE). The studies of the last two decades have unveiled somewhat controversial data on the diagnostic applicability of anti-MBP autoantibodies as a disease' marker. Here, we present the results of new functional analysis of the anti-MBP autoantibodies isolated from MS (in patients) and EAE (in mice) sera, based on their proteolytic activity against the targeted autoantigen. The activity was shown to be the intrinsic property of the IgG molecule. No activity was found in the sera-derived antibody fraction of healthy donors and control mice. Sera of 24 patients with clinically proven MS at different stages of the disease, and 20 healthy controls were screened for the anti-MBP antibody-mediated proteolytic activity. The activity correlated with the scores on the MS expanded disability status scale (EDSS) (r(2)=0.85, P<0.001). Thus, the anti-MBP autoantibody-mediated proteolysis may be regarded as an additional marker of the disease progression.

[Autoantibody profile among Kaingang and Guarani tribe Indians in Southern Brazil].

Science.gov (United States)

Utiyama, S R; Guardiano, J; Petzl-Erler, M L; Mocelim, V; de Messias-Reason, I J

2000-06-01

This study investigated the autoantibody profile of 241 blood samples from 176 Kaingang and 65 Guarani Indians from three populations living on the Rio das Cobras and Ivaí reservations, in the state of Paraná, in southern Brazil. The presence of antimitochondrial, anti-smooth muscle, antinuclear, anti-parietal cell, and anti-liver-kidney microsome antibodies was determined by indirect immunofluorescence. These results were compared with samples from 100 healthy Caucasian individuals from the general population of the state. Total positivity was 9% for the indigenous population and 4% for the control population. The prevalence of anti-smooth muscle antibodies was significantly higher among the Guarani and Kaingang individuals from the Rio das Cobras reservation (P = 0.03). It is likely that the increased exposure that these indigenous Brazilians have to infectious diseases that were previously unknown to them comes from more contact with non-native populations, growing acculturation, and cultural practices that include scarification and tattooing. The presence of auto-antibodies in these Brazilian Indians may be related to mechanisms of molecular mimicry with viral or bacterial antigens.

Novel Endogenous, Insulin-Stimulated Akt2 Protein Interaction Partners in L6 Myoblasts.

Directory of Open Access Journals (Sweden)

Michael Caruso

Full Text Available Insulin resistance and Type 2 diabetes are marked by an aberrant response in the insulin signaling network. The phosphoinositide-dependent serine/threonine kinase, Akt2, plays a key role in insulin signaling and glucose uptake, most notably within skeletal muscle. Protein-protein interaction regulates the functional consequence of Akt2 and in turn, Akt2's role in glucose uptake. However, only few insulin-responsive Akt2 interaction partners have been identified in skeletal muscle cells. In the present work, rat L6 myoblasts, a widely used insulin sensitive skeletal muscle cell line, were used to examine endogenous, insulin-stimulated Akt2 protein interaction partners. Akt2 co-immunoprecipitation was coupled with 1D-SDS-PAGE and fractions were analyzed by HPLC-ESI-MS/MS to reveal Akt2 protein-protein interactions. The pull-down assay displayed specificity for the Akt2 isoform; Akt1 and Akt3 unique peptides were not detected. A total of 49 were detected with a significantly increased (47 or decreased (2 association with Akt2 following insulin administration (n = 4; p<0.05. Multiple pathways were identified for the novel Akt2 interaction partners, such as the EIF2 and ubiquitination pathways. These data suggest that multiple new endogenous proteins may associate with Akt2 under basal as well as insulin-stimulated conditions, providing further insight into the insulin signaling network. Data are available via ProteomeXchange with identifier PXD002557.

Myositis-specific autoantibodies and their association with malignancy in Italian patients with polymyositis and dermatomyositis.

Science.gov (United States)

Ceribelli, Angela; Isailovic, Natasa; De Santis, Maria; Generali, Elena; Fredi, Micaela; Cavazzana, Ilaria; Franceschini, Franco; Cantarini, Luca; Satoh, Minoru; Selmi, Carlo

2017-02-01

This study aims to characterize myositis-specific antibodies in a well-defined cohort of patients with idiopathic inflammatory myopathy and to determine their association with cancer. Sera from 40 patients with polymyositis, dermatomyositis, and controls were tested by protein and RNA immunoprecipitation to detect autoantibodies, and immunoprecipitation-Western blot was used for anti-MJ/NXP-2, anti-MDA5, and anti-TIF1γ/α identification. Medical records were re-evaluated with specific focus on cancer. Anti-MJ/NXP-2 and anti-TIF1γ/α were the most common antibodies in dermatomyositis. In six dermatomyositis cases, we found five solid forms of cancer and one Hodgkin's lymphoma in long-term remission. Among patients with cancer-associated dermatomyositis, three were positive for anti-TIF1γ/α, two for anti-Mi-2, and one for anti-MJ/NXP-2. The strongest positivity of anti-TIF1γ was seen in two active forms of cancer, and this antibody was either negative or positive at low titers in the absence of cancer or in the 7-year remission Hodgkin's lymphoma. Four out of twenty (20 %) patients with polymyositis had solid cancer, but no specific association with autoantibodies was identified; further, none of the four cases of antisynthetase syndrome had a history of cancer. No serum myositis-associated autoantibody was observed in control sera, resulting in positive predictive value 75 %, negative predictive value 78.5 %, sensitivity 50 %, specificity 92 %, and area under the ROC curve 0.7083 for the risk of paraneoplastic DM in anti-TIF1γ/α (+) patients. Myositis-specific autoantibodies can be identified thanks to the use of immunoprecipitation, and their association with cancer is particularly clear for anti-TIF1γ/α in dermatomyositis. This association should be evaluated in a prospective study by immunoprecipitation in clinical practice.

Insulin receptors

International Nuclear Information System (INIS)

Kahn, C.R.; Harrison, L.C.

1988-01-01

This book contains the proceedings on insulin receptors. Part A: Methods for the study of structure and function. Topics covered include: Method for purification and labeling of insulin receptors, the insulin receptor kinase, and insulin receptors on special tissues

Enhanced insight into the autoimmune component of glaucoma: IgG autoantibody accumulation and pro-inflammatory conditions in human glaucomatous retina.

Science.gov (United States)

Gramlich, Oliver W; Beck, Sabine; von Thun Und Hohenstein-Blaul, Nadine; Boehm, Nils; Ziegler, Anika; Vetter, Jan M; Pfeiffer, Norbert; Grus, Franz H

2013-01-01

There is accumulating evidence that autoimmune components, such as autoantibodies and autoantibody depositions, play a role in the pathogenesis of neurodegenerative diseases like Alzheimeŕs disease or Multiple Sclerosis. Due to alterations of autoantibody patterns in sera and aqueous humor, an autoimmune component is also assumed in the pathogenesis of glaucoma, a common reason for irreversible blindness worldwide. So far there has been no convincing evidence that autoantibodies are accumulated in the retina of glaucoma patients and that the local immune homeostasis might be affected. Six human glaucomatous donor eyes and nine samples from donors with no recorded ocular disease were included. Antibody microarrays were used to examine the patterns of pro-inflammatory proteins and complement proteins. Analysis of TNF-α and interleukin levels revealed a slight up-regulation exclusively in the glaucomatous group, while complement protein levels were not altered. IgG autoantibody accumulations and/or cellular components were determined by immunohistology (n = 4 per group). A significantly reduced number of retinal ganglion cells was found in the glaucomatous group (healthy: 104±7 nuclei/mm, glaucoma: 67±9 nuclei/mm; p = 0.0007). Cell loss was accompanied by strong retinal IgG autoantibody accumulations, which were at least twice as high as in healthy subjects (healthy: 5.0±0.5 IgG deposits/100 cells, glaucoma: 9.4±1.9 IgG deposits/100 cells; p = 0.004). CD27(+) cells and CD27(+)/IgG(+) plasma cells were observed in all glaucomatous subjects, but not in controls. This work provides serious evidence for the occurrence of IgG antibody deposition and plasma cells in human glaucomatous retina. Moreover, the results suggest that these IgG deposits occurred in a pro-inflammatory environment which seems to be maintained locally by immune-competent cells like microglia. Thereby, glaucoma features an immunological involvement comparable to other

Potent Insulin Secretagogue from Scoparia dulcis Linn of Nepalese Origin.