Majority Of Autoantibodies Research Articles

The role of GaD65, ZNTS, IA-2, and IAA as predictive biomarkers for type 1 diabetes mellitus in children

Background Type 1 diabetes mellitus (T1DM) is a chronic disorder characterized by immune-mediated harm to the pancreatic β-cells that produce insulin. The four major autoantibodies implicated in the pathophysiology are insulin autoantibodies, glutamic acid decarboxylase antibodies, tyrosine phosphatase antibodies, and zinc transporter 8 antibodies. Objective We examined whether children with T1DM have particular antibodies related to T1DM and their association with clinical features. Materials and methods The study involved 60 Iraqi children who had been diagnosed with T1DM within the last 3 years, as well as a control group of 60 healthy individuals without diabetes or autoimmune diseases. Blood samples were collected from all participants to analyze the levels of serum autoantibodies, specifically insulin (IAA), glutamic acid decarboxylase (GADA), tyrosine phosphatase (IA-2A), and zinc transporter 8 (ZnT8A), using an enzyme-linked immunosorbent assay (Sandwich-ELISA). Results and conclusion The findings revealed that a significant number of patients with diabetes had elevated levels of antibodies against zinc transporter 8 (P<0.001), tyrosine phosphatase (P<0.001), insulin autoantibodies (P<0.001), and glutamic acid decarboxylase (P<0.001). Glutamic acid decarboxylase 65 antibodies were found to be the most prevalent. All four biomarkers showed remarkable effectiveness in distinguishing positive and negative cases. Logistic regression analysis revealed that glutamic acid decarboxylase 65 and insulin antibodies were significantly associated with the outcome, while tyrosine phosphatase and zinc transporter 8 did not show such a relationship. These findings indicate that measurements of anti-zinc transporter 8, tyrosine phosphatase, insulin autoantibodies, and glutamic acid decarboxylase could be important diagnostic markers for identifying patients with T1DM, aiding in early detection and understanding the disease process.

Generation and pathogenicity of autoantibodies associated to thrombosis and hemostasis

Many acquired bleeding and thrombotic complications are provoked by autoantibodies to blood coagulation factors, or to hemostasis inhibitors and regulatory proteins. If occurrence of those antibodies remains rare or ultra-rare, affected patients are not always well-identified and associated pathologies are not always understood. Today, autoantigens tend to be better characterized. New available methods allow investigating structural changes of body components, responsible for auto-immunization. This renders it possible to develop laboratory assays for detecting autoantibodies and estimating their blood concentration. This review analyzes the major autoantibodies reported to be associated with hemorrhagic or thrombotic pathologies and their possible inducing causes when known. Pathogenicity is strongly patient- and context-dependent and is related to autoantibodies’ concentration, avidity, and capacity to bind to autoantigen structures in-vivo, misdirecting the immune system to the own body’s cells or organs. Identification of autoantigens allows for developing laboratory methods for testing autoantibodies and following their evolution kinetics. In-vitro investigations concern functional assays, to evaluate autoantibody’s capacity to inhibit physiological activities, or autoantigen-capture-based assays to detect autoantibodies, like with enzyme-linked immuno-sorbent assay (ELISA) methods. Exploring patients with autoimmune complications remains difficult as few specific assays are available. They mainly concern diseases with the highest incidence, like anti-phospholipid antibodies, lupus anticoagulants, or heparin-dependent antibodies. The present understanding suggests that antibodies to ubiquitous components, like phospholipids or polysaccharides, are actually targeted to proteins with a strong affinity binding to those components: Autoantibodies are not directed to phospholipids, but to phospholipid-binding proteins, and heparin-dependent antibodies are not directed to anticoagulant polysaccharides, but to platelet factor 4. Most pathogenic autoantibodies are of immunoglobulin G (IgG) isotype, but in some cases, IgM or IgA isotypes can be involved. Identification and characterization of autoantibodies associated to hemorrhagic or thrombotic pathologies remains complex at the laboratory level, although they are of high relevance for the right management of concerned patients.

The Predictive Value of Autoantibodies in Determining Autoimmune Hepatitis (AIH) Severity

Background: The presence of autoantibodies is a prerequisite for the diagnosis of autoimmune hepatitis (AIH). However, most autoantibodies are not disease-specific, and serological overlap between AIH and other chronic liver diseases is common. Since the prognostic parameters of AIH are limited, this study aimed to investigate the relationship between histopathological findings on liver biopsy with different types of autoantibodies associated with AIH and how autoantibodies can predict the severity and extent of disease. Methods: The present study was performed on 30 patients with a definite diagnosis of AIH according to the International Autoimmune Hepatitis Group (IAIHG) criteria. Pediatric AIH patients underwent liver tissue examinations at the time of diagnosis at accession, which confirmed characteristic histological changes. AIH-related serologic major and minor autoantibodies were measured using indirect immunofluorescence assays and ELISA kit (EUROIMMUN, Germany), respectively, and were compared within all patients, and the results were recorded. Finally, the obtained data were analyzed using SPSS V25 software. Results: Out of 30 patients, 17 (56.66%) were female, and the age range of patients was 17-11 years (8.46±6.95). Anti-nuclear antibody (ANA) (73.3%), smooth muscle antibody (SMA)-anti-smooth muscle actin antibody (ASMA) (70%), perinuclear anti-neutrophilic cytoplasmic antibodies (p-ANCA) (63%), and liver kidney microsomal (LKM) (43.3%) were the most common autoantibodies found in children with AIH. There was a significant relation between the severity of histological findings and the presence of LKM antibodies (P<0.05). The highest sensitivity for predicting severe AIH based on histopathological findings was ANA autoantibody positivity and the presence of at least two primary autoantibodies (LKM and SMA-ASMA). On the other hand, positive LKM antibodies had the highest specificity and positive predictive value (PPV) in AIH severity prediction. Conclusion: The results of the present study suggested that there might be a significant correlation between the presence of primary LKM autoantibodies and biopsy results, so it can possibly act as an accurate autoantibody for predicting the severity of AIH, while other AIH-related autoantibodies did not seem to have a significant correlation with biochemical and histological findings.

166 CLINICAL IMPACT OF NEW BIOMARKERS IN THE PATIENTS WITH ESOPHAGEAL CARCINOMA

Abstract We have developed several new biomarkers in patients with esophageal carcinoma. In this paper, we reviewed the clinical impact of serum autoantibodies, growth factors, blood counts, and other serum tumor markers. Methods Blood samples of patients with esophageal carcinoma were obtained before surgery and were stored at −80°C until the ELISA assay. Target tumor antigens for autoantibodies were SURF1, LOC, HOOK2, AGENCOURT, TROP-2, TRIM21, GLUT-1, Myomegalin, Makorin-1, CUEC-23, ECSA-1, p53, and NY-ESO-1. Growth factor-related molecules were followed; midkine, VEGF, PDECGF, and HGF. The other markers were followed; platelet, CRP, IAP, SCC-Ag, CYFRA21-1, and fibrinogen. Results A total of 24 biomarkers were evaluated for their clinical impact on patients’ survival and tumor stages. High positive rates, more than 40% were found in SURF1, Myomegalin, midkine, and HGF. Although the majority of autoantibodies did not have a prognostic impact, all the growth factors have a prognostic impact on patients’ survival. Lutine blood tests, such as platelet count, neutrophil-lymphocyte ratio, fibrinogen, and CRP, were also useful to predict prognosis. Conclusion We have evaluated the clinical impact of 24 new biomarkers, including 13 autoantibodies, for the patients with esophageal carcinoma. Although the autoantibodies were useful to detect relatively early stage of the disease, the prognostic impact of these biomarkers was limited. All growth factors were useful to predict patients’ survival.

158-LB: A Complete-Panel Islet Autoantibody Multiplex ECL Assay

Background: Type 1 diabetes (T1D), a major chronic autoimmune disease starting mostly from childhood, is now predictable with the measurement of four major islet autoantibodies (IAbs) including IAA, GADA, IA-2A and ZnT8A. Currently, there are approximately 1.4 million people affected with T1D in the United States and the incidence has doubled in the last 20 years, especially in young children. Mass screening for eligible subjects and the general population remains inefficiency and laborious bottleneck. Methods: With the platform of our extensively validated high affinity electrochemiluminescence (ECL) assay, we have developed a simple multiplexed ECL assay to combine all four major IAb assays in a single well. Two cohorts were studied including 80 samples from newly diagnosed patients with T1D and 1,140 from Autoimmunity Screening for Kids (ASK) study. Both multiplex ECL assay and standard radio-binding assay (RBA) were performed in parallel. Results: With >99th percentile of specificity for both assays in over 1,000 samples from general population, sensitivity of multiplex ECL assay in new onset patients with T1D were similar to RBA, GADA 75% vs. 71%; IA-2A 91% vs. 90%; IAA 61% vs. 65%; ZnT8A 90% vs. 87%. In ASK cohort, multiplex ECL assay was concordant with RBA among children with multiple IAbs (42/44, 96%). In contrast, only 39% (21/54, p<0.0001) of children with single IAb by RBA were positive by multiplex ECL assay. Conclusion: Multiplex ECL assay illustrated its high sensitivity/specificity as RBA in T1D patients. In general population screening, multiplex ECL assay, similar to single ECL assay, is capable to discriminate high risk IAbs from low risk IAbs generated by RBA. With a multiplexing feature, it provides a high throughput tool with low cost and low sample volume for large scale of population screening for T1D. Disclosure L. He: None. X. Jia: None. D. Miao: None. C. Geno rasmussen: None. M. Rewers: Advisory Panel; Self; Provention Bio, Inc., Consultant; Self; RTI, Research Support; Self; Janssen Research & Development, LLC, JDRF. L. Yu: None. Funding JDRF (2-SRA-2018-533-S-B, 1-SRA-2016-208-S-B); National Institutes of Health (DK32083); Diabetes Research Center (P30DK116073)

O18 Integrated molecular analysis of systemic sclerosis skin and blood shows significant differences between major autoantibody subgroups

Abstract Background/Aims The major antinuclear autoantibodies of systemic sclerosis (SSc) associate with different skin score trajectories and risk of internal organ manifestations. To elucidate molecular differences between ANA-defined subgroups, we utilised the prospective BIOPSY cohort of well-characterised SSc patients. Methods The prospectively collected BIOPSY cohort recruited 52 SSc patients (21 early dcSSc, 15 established dcSSc, 16 lcSSc) and 16 healthy controls (HC). 36 (69%) of the SSc patients are female. Mean disease duration in the early dcSSc cohort was 24 months (sd 12 months), and in established dcSSc was 11.3 years. ANA frequency in BIOPSY reflected the overall dcSSc population: anti-topoisomerase-1 (ATA) n = 14 (27%), anti-RNA pol III (ARA) n = 12 (23%) and other n = 26 (50%). Mean baseline skin score (MRSS) for early dcSSc was 21 (sd 11.2). At a group level mRSS peak was 21.9 (11.8) at 3 months and fell to 19.1(10.5) at 12 months. Serum biomarkers of ECM turnover and fibrosis were measured three monthly and genome-wide transcriptomic profiling of whole skin and whole blood performed by RNA-Seq. Statistical analysis used RStudio with ANOVA, and Tukey post-hoc test. Differential gene expression used the Bioconductor limma software, with standard thresholds for significance. Results At baseline, there were differences in soluble markers between clinical SSc sugroups and HC but not for major ANA subgroups. However, we found clear differences in early dcSSc analysed by major ANA subset for longitudinal change in serum markers of fibrosis and in whole skin gene expression, suggesting a mechanistic basis for the distinct clinical phenotypes associated with hallmark ANAs. During follow-up, significant differences were observed in HA, TIMP1, and PIIINP at 6 and 12 months (p < 0.05), with stable levels in ATA+ patients compared to progressively increased levels in the other subgroups. There were 564 significantly differentially expressed genes in skin between early dcSSc and HC. Unsupervised clustering differentiated patients with ARA and ATA positivity with early dcSSc. 54 genes were significantly differentially expressed in skin between ATA and ARA patients. Whilst 179 genes were differentially expressed in whole blood between early dcSSc compared with HC, no genes could significantly differentiate ATA from ARA. Functional analysis using HALLMARK pathway analysis identified both shared pathways associated with SSc across ANA groups (e.g. TGF beta signaling, IL6 JAK STAT3 signalling, inflammatory response), and pathways only upregulated in patients with ATA (e.g. Wnt beta catenin signaling, Notch signaling), and ARA (e.g. interferon gamma response, adipogenesis). Conclusion We have found significant differences in skin gene expression and longitudinal change in serum markers by autoantibody specificity in dcSSc. Our findings have implications for SSc pathogenesis and support stratification by ANA subgroup in clinical studies. Disclosure K.E. Clark: None. C. Campochiaro: None. E. Csomor: Corporate appointments; employee of GSK. A. Taylor: Corporate appointments; employee of GSK. K. Nevin: Corporate appointments; employee of GSK. N. Galwey: Corporate appointments; employee of GSK. M.A. Morse: Corporate appointments; employee of GSK. V.H. Ong: None. E. Derrett-Smith: None. N. Wisniacki: Corporate appointments; employee of GSK. S. Flint: Corporate appointments; employee of GSK. C.P. Denton: Consultancies; Actelion, GlaxoSmithKline, Bayer, Sanofi, lnventiva, Boehringer Ingelheim, Roche, Bristol Myers Squibb, CSL Behring, UCB, Leadiant Biosciences, Corbus, Servier, Arxx Therapeutics.

Neutrophil Extracellular Traps in Systemic Lupus Erythematosus Stimulate IgG2 Production From B Lymphocytes.

Circulating autoantibodies of IgG2 isotype predominate in Systemic Lupus Erythematosus (SLE) and concur to the development of the renal lesions characteristic of Lupus Nephritis (LN). Anti-dsDNA and anti-histones IgG2, together with anti-podocyte proteins (i.e., α-enolase) are the major autoantibodies in serum and renal glomeruli of LN patients. The mechanisms underlying autoantibody formation and isotype switching in SLE and LN are unknown. A major issue is how DNA/histones are externalized from cell nucleus, driving the autoimmune response. Neutrophil Extracellular Traps (NETs) have been recently identified as crucial players in this context, representing the main source of DNA and nucleosome proteins. A second key point is what regulates IgG2 isotype switching: in mouse models, T-bet transcription factor has been described as essential for IgG2a class switch. We hypothesized that, in SLE, NET formation is the key mechanism responsible for externalization of autoantigens (i.e., dsDNA, histones 2,3, and α-enolase) and that T-bet is upregulated by NETs, driving, in this way, immunoglobulin class switch recombination (CSR), with production of IgG2 autoantibodies. The data here presented show that NETs, purified from SLE patients, stimulate ex vivo IgG2 isotype class switch possibly through the induction of T-bet. Of note, we observed a prominent effect of NETs on the release of soluble IgG2 in SLE patients', but not in healthy donors' B cells. Our results add important knowledge on the mechanisms of IgG2 class switch in SLE and contribute to further elucidate the role of NETs in LN pathogenesis.

Autoantibodies against zinc transporter 8 further stratify the autoantibody-defined risk for type 1 diabetes in a general population of schoolchildren and have distinctive isoform binding patterns in different forms of autoimmune diabetes: results from the Karlsburg Type 1 Diabetes Risk Study.

To evaluate the diagnostic relevance of autoantibodies against zinc transporter 8 (ZnT8) in schoolchildren from the general population as well as in people with autoimmune diabetes. A total of 137 schoolchildren positive for at least one of the three major diabetes-associated autoantibodies, without diabetes heredity or preselection on HLA typing, from the Karlsburg Type 1 Diabetes Risk Study, as well as 102 people at type 1 diabetes onset, 88 people with latent autoimmune diabetes in adults and 119 people with type 2 diabetes, were analysed for different ZnT8 autoantibody variants. Zinc transporter 8 autoantibody positivity was found in 18% of autoantibody-positive schoolchildren, with a noticeable association with other autoantibodies associated with type 1 diabetes and disease progression. Furthermore, ZnT8 autoantibody positivity was associated with diabetes progression in schoolchildren positive for autoantibodies against insulinoma-associated antigen-2 (IA-2) and, importantly, in seven IA-2 autoantibody-negative schoolchildren. Additionally, ZnT8 autoantibodies were found in 56% of people with type 1 diabetes, predominantly directed against all three ZnT8 variants and comparable to schoolchildren with multiple autoantibodies. In contrast, ZnT8 autoantibodies were detected in 10% of people with latent autoimmune diabetes in adults, none of them with reactivity to all three isoforms. Zinc transporter 8 autoantibodies are useful markers for prediction of type 1 diabetes in a general population, further stratifying the risk of progression in autoantibody-positive children. ZnT8 autoantibodies are also important markers in adult-onset diabetes, with a completely different reaction pattern in type 1 diabetes in comparison to latent autoimmune diabetes in adults, and may therefore help to differentiate between the two forms.

Immunological features in anti-U1-ribonucleoprotein antibody positive patients with systemic scleroderma

In anti-U1-ribonucleoprotein (anti-U1-RNP) antibody positive patients with systemic scleroderma (SSD), the clinical picture and course of the disease have specific features: there is a preponderance of its limited form; inflammatory damage to the joints and muscles comes to the fore; and cutaneous manifestations are mild. Moreover, a high frequency (68%) of interstitial lung disease is found. At the same time, the autoimmune profile in this group has been little studied.Objective:to investigate the level of major autoantibodies (autoAbs) in anti-U1RNP antibody positive patients with SSD and to compare the frequency of the autoAbs in this group and in the groups of patients with SSD phenotypes associated with anti-centromere antibodies (ACA) and anti-topoisomerase I (anti-Scl70) antibodies.Patients and methods. The investigation enrolled a total of 144 patients meeting the 2013 ACR/EULAR SSD classification criteria. Forty-four anti-U1RNP antibody positive patients were found to have autoAbs, rheumatoid factor (RF), anti-cyclic citrullinated peptide (ACCP), anti-Ro, anti-La, anti-double-stranded DNA (anti-dsDNA), anti-Smith (anti-Sm), anti-cardiolipin (aCL), anti-histidyl tRNA synthetase (anti-Jo1), anti-Scl70, and anti-RNA polymerase III (anti-RNAP-III) antibodies, and ACA in two points. The study group (anti-U1RNP antibody positive patients with SSD) and the comparison groups (anti-Scl70 and ACA positive patients) were comparatively analyzed.Results and discussion. Anti-U1RNP antibody positive patients with SSD were commonly observed to have overlaps (34%) with rheumatoid arthritis and systemic lupus erythematosus, as well as concurrence with Sjögren’s syndrome (SS) (32.5%). The study group was found to have frequently RF (27%), anti-Ro (41%), anti-dsDNA (50%) antibodies, rarely anti-Sm (9%), ACCP (9%), anti-La (7%), ACA (11%), anti-Scl70 (9%), and aCL (2%) antibodies. Anti-Jo1 and anti-RNAP-III antibodies were not detected in any patient. SSD patients who were highly positive for anti-U1RNP antibodies (more than 2 upper limits of the reference range) significantly more frequently exhibited RF, anti-Ro and anti-dsDNA antibodies (p<0.01). Over time, anti-U1RNP antibodies detected at the onset of the disease persisted in 75% of patients. autoAbs were observed to disappear in patients with a low baseline titer of anti-U1RNP antibodies. Re-examination demonstrated that the detection rate of other autoAbs remained high in the group of patients who were highly positive for anti-U1RNP antibodies. Comparison of the three groups showed that the specific feature of the study group was the more frequent presence of other autoAbs, among which anti-Ro antibodies were most important. Their presence was associated with SS.Conclusion. In addition to clinical features, patients with SSD and anti-U1RNP antibody overproduction differ from those with major SSD phenotypes by the more frequent presence of other autoAbs. Persons who are highly positive for anti-U1RNP show the steady-state elevated levels of RF, anti-Ro and anti-dsDNA antibodies and the rare detection of SSD-specific autoAbs (ACA, anti-Scl70 and anti-RNAP-III).

The Value of Intravenous Immunoglobulin Therapy in Idiopathic Inflammatory Myositis in the Current Transformed Era of Biologics.

The understanding of etiology and pathogenesis of idiopathic immune myositis is fast evolving, and so is the classification of myositis subtypes. The diversity in genetics, major histocompatibility complex expressions, immunohistochemical, and specific and associated autoantibodies not only explains the individual variability in response to therapies but also begs for subtype-specific treatments. With the evolution of the new biological therapies, the treatment of idiopathic immune myositis (IIM) has greatly transformed in recent years. This article appraises the current therapeutic value of intravenous immunoglobulin (IVIg) in idiopathic immune myopathy patients in the era of transformed treatment options. This article argues why the IVIg therapy still retains its value as an unreplaceable treatment option in certain specific subtypes of idiopathic immune myositis patients as well as in certain specific clinical idiopathic immune myositis scenarios.

Antigen-driven selection of antibodies against SSA, SSB and the centromere ‘complex’, including a novel antigen, MIS12 complex, in human salivary glands

ObjectivesRecent evidences have revealed that anti-SSA/SSB antibodies, the major autoantibodies in Sjögren's syndrome (SS), are produced in salivary glands. This study aims to clarify overall of autoantibody production at lesion...

Occurrence of major anti-retinal autoantibodies associated with paraneoplastic autoimmune retinopathy

Autoantibodies (AAbs) against retinal antigens can be found in patients with cancer and unexplained vision loss unrelated to the cancer metastasis. Cancer-associated retinopathy (CAR) is a rare paraneoplastic visual syndrome mediated by AAbs. Our goal was to determine whether CAR patients with different malignancies have a specific AAb or repertoire of AAbs that could serve as biomarkers for retinal disease. We found AAbs against 12 confirmed retinal antigens, with α-enolase being the most frequently recognized. The significant finding of the study was a high incidence of anti-aldolase AAbs in colon-CAR, anti-CAII in prostate-CAR, and anti-arrestin in skin melanoma patients thus these AAbs could serve as biomarkers in the context of clinical presentation and could support the diagnosis of CAR. However, a lack of AAb restriction to any one antigenic protein or to one retinal cellular location makes screening for a CAR biomarker challenging.

Preferential Reactivity of Dipeptidyl Peptidase-IV Inhibitor-Associated Bullous Pemphigoid Autoantibodies to the Processed Extracellular Domains of BP180.

Bullous pemphigoid (BP) is a common autoimmune blistering disease in which autoantibodies target the hemidesmosomal components BP180 and/or BP230 in basal keratinocytes. In BP, 80 to 90% of autoantibodies target the juxtamembranous extracellular non-collagenous 16th A (NC16A) domain of BP180. Recently, the administration of dipeptidyl peptidase-IV inhibitors (DPP4i), which are widely used as antihyperglycemic drugs, has been recognized to be a causative factor for BP. DPP4i-associated BP (DPP4i-BP) autoantibodies tend to target epitopes on non-NC16A regions of BP180, and the pathomechanism for the development of the unique autoantibodies remains unknown. To address the characteristics of DPP4i-BP autoantibodies in detail, we performed epitope analysis of 18 DPP4i-BP autoantibodies targeting the non-NC16A domains of BP180 using various domain-specific as well as plasmin-digested polypeptides derived from recombinant BP180. Firstly, Western blotting showed that only one DPP4i-BP serum reacted with the epitopes on the intracellular domain of BP180, and no sera reacted with the C-terminal domain of the molecule. In addition, only 2 DPP4i-BP sera reacted with BP230 as determined by enzyme-linked immunosorbent assay. Thus, DPP4i-BP autoantibodies were found to mainly target the non-NC16A mid-portion of the extracellular domain of BP. Interestingly, Western blotting using plasmin-digested BP180 as a substrate revealed that all of the DPP4i-BP sera reacted more intensively with the 97-kDa processed extracellular domain of BP180, which is known as the LABD97 autoantigen, than full-length BP180 did. All of the DPP4i-BP autoantibodies targeting the LABD97 autoantigen were IgG1, and IgG4 was observed to react with the molecule in only 7 cases (38.9%). In summary, the present study suggests that IgG1-class autoantibodies targeting epitopes on the processed extracellular domain of BP180, i.e., LABD97, are the major autoantibodies in DPP4i-BP.

Characteristics of slow progression to diabetes in multiple islet autoantibody-positive individuals from five longitudinal cohorts: the SNAIL study

Aims/hypothesisMultiple islet autoimmunity increases risk of diabetes, but not all individuals positive for two or more islet autoantibodies progress to disease within a decade. Major islet autoantibodies recognise insulin (IAA), GAD (GADA), islet antigen-2 (IA-2A) and zinc transporter 8 (ZnT8A). Here we describe the baseline characteristics of a unique cohort of ‘slow progressors’ (n = 132) who were positive for multiple islet autoantibodies (IAA, GADA, IA-2A or ZnT8A) but did not progress to diabetes within 10 years.MethodsIndividuals were identified from five studies (BABYDIAB, Germany; Diabetes Autoimmunity Study in the Young [DAISY], USA; All Babies in Southeast Sweden [ABIS], Sweden; Bart’s Oxford Family Study [BOX], UK and the Pittsburgh Family Study, USA). Multiple islet autoantibody characteristics were determined using harmonised assays where possible. HLA class II risk was compared between slow progressors and rapid progressors (n = 348 diagnosed <5 years old from BOX) using the χ2 test.ResultsIn the first available samples with detectable multiple antibodies, the most frequent autoantibodies were GADA (92%), followed by ZnT8A (62%), IAA (59%) and IA-2A (41%). High risk HLA class II genotypes were less frequent in slow (28%) than rapid progressors (42%, p = 0.011), but only two slow progressors carried the protective HLA DQ6 allele.ConclusionNo distinguishing characteristics of slow progressors at first detection of multiple antibodies have yet been identified. Continued investigation of these individuals may provide insights into slow progression that will inform future efforts to slow or prevent progression to clinical diabetes.

Major Component Diseases, Autoantibodies, and Typical Clinical and Endocrinological Findings Observed in Each Type of Polyglandular Autoimmune Syndrome

Major Component Diseases, Autoantibodies, and Typical Clinical and Endocrinological Findings Observed in Each Type of Polyglandular Autoimmune Syndrome

Red cell alloimmunization is associated with development of autoantibodies and increased red cell transfusion requirements in myelodysplastic syndrome.

Up to 90% of patients with a myelodysplastic syndrome require red blood cell transfusion; nevertheless, comprehensive data on red cell alloimmunization in such patients are limited. This study evaluates the incidence and clinical impact of red cell alloimmunization in a large cohort of patients with myelodysplastic syndrome registered in the statewide South Australian-MDS registry. The median age of the 817 patients studied was 73 years, and 66% were male. The cumulative incidence of alloimmunization was 11%. Disease-modifying therapy was associated with a lower risk of alloimmunization while alloimmunization was significantly higher in patients with a revised International Prognostic Scoring System classification of Very Low, Low or Intermediate risk compared to those with a High or Very High risk (P=0.03). Alloantibodies were most commonly directed against antigens in the Rh (54%) and Kell (24%) systems. Multiple alloantibodies were present in 49% of alloimmunized patients. Although 73% of alloimmunized patients developed alloantibodies during the period in which they received their first 20 red cell units, the total number of units transfused was significantly higher in alloimmunized patients than in non-alloimmunized patients (90±100 versus 30±52; P<0.0001). In individual patients, red cell transfusion intensity increased significantly following alloimmunization (2.8±1.3 versus 4.1±2.0; P<0.0001). A significantly higher proportion of alloimmunized patients than non-alloimmunized patients had detectable autoantibodies (65% versus 18%; P<0.0001) and the majority of autoantibodies were detected within a short period of alloimmunization. In conclusion, this study characterizes alloimmunization in a large cohort of patients with myelodysplastic syndrome and demonstrates a signficant increase in red cell transfusion requirements following alloimmunization, most probably due to development of additional alloantibodies and autoantibodies, resulting in subclinical/clinical hemolysis. Strategies to mitigate alloimmunization risk are critical for optimizing red cell transfusion support.

Autoantibodies in Diabetes Mellitus

Based on American Diabetes Association (ADA), diabetes can be classified into the following general categories: type 1 diabetes (T1D), type 2 diabetes (T2D), gestational diabetes mellitus (GDM) and specific types of diabetes due to other cause. Obesity is by far the main underlying factor causing T2D and its pathological potential lies in obesity-associated insulin resistance, activation of innate immunity and chronic low-grade inflammation. When tissue inflammation induced, tissue destruction occurs, 'self' antigens, which are generally not accessible to T cells, can be released from the affected tissues and promote autoimmune activation. The 4 major autoantibodies are islet-cell cytoplasmic autoantibodies (ICA), glutamid acid decarboxylase antibody (GADA), islet antigen-2 antibody (IA-2A) and insulin autoantibodies (IAA). In addition, ZnT8A has recently been found to predict T1D. ZnT8 is contained in the islets of Langerhans, with the highest expression is in β cells of the pancreas. ZnT8A measurements simultaneously with GADA, IA-2A and IAA achieve rates of 98% detection for onset level of autoimmune diabetes. Presence of antibodies in T2D also shows the potential serious complications compared with T2D without antibodies. The combination of GADA, IA-2A and ZnT8A can be suggested as the most powerful and cost-effective diagnostic approach in patients with T1D.Keywords: autoantibody, autoimmune, diabetes mellitus, ICA, GADA, IA-2A, IAA, ZnT8A

T1D Autoantibodies: room for improvement?

Type 1 diabetes (T1D) is now predictable by measuring major islet autoantibodies (IAbs) against insulin and other pancreatic β cells proteins including GAD65 (GADA), islet antigen 2 (IA-2A), and zinc transporter 8 (ZnT8A). The assay technology for IAbs has made great progress; however, several important aspects still need to be addressed and improved. Currently a radio-binding assay has been well established as the 'gold' standard assay for all four IAbs. New generation of nonradioactive IAb assay with electrochemiluminescence technology has been shown to further improve sensitivity and disease specificity. Recently, multiplexed assays have opened the possibility of more efficient screening in large populations. Identification of potential new autoantibodies to neo-antigens or neo-epitopes posttranslational modification is a new important field to be explored. Individuals having a single positive autoantibody are at low risk for progression to T1D, whereas individuals expressing two or more positive autoantibodies, especially on multiple tests over time, have nearly 100% risk of developing clinical T1D when followed for over two decades. More efficient and cost effective IAb assays will hopefully lead to point-of-care screening in the general population.

Major Component Diseases, Autoantibodies, and Typical Clinical and Endocrinological Findings Observed in Each Type of Polyglandular Autoimmune Syndrome

Major Component Diseases, Autoantibodies, and Typical Clinical and Endocrinological Findings Observed in Each Type of Polyglandular Autoimmune Syndrome

Periodic Acid-Schiff Staining Parallels the Immunoreactivity Seen By Direct Immunofluorescence in Autoimmune Skin Diseases.

Background:In many countries and laboratories, techniques such as direct immunofluorescence (DIF) are not available for the diagnosis of skin diseases. Thus, these laboratories are limited in the full diagnoses of autoimmune skin diseases, vasculitis, and rheumatologic diseases. In our experience with these diseases and the patient's skin biopsies, we have noted a positive correlation between periodic acid-Schiff (PAS) staining and immunofluorescence patterns; however, these were just empiric observations. In the current study, we aim to confirm these observations, given the concept that the majority of autoantibodies are glycoproteins and should thus be recognized by PAS staining.Aims:To compare direct immunofluorescent and PAS staining, in multiple autoimmune diseases that are known to exhibit specific direct immunofluorescent patterns.Materials and Methods:We studied multiple autoimmune skin diseases: Five cases of bullous pemphigoid, five cases of pemphigus vulgaris, ten cases of cutaneous lupus, ten cases of autoimmune vasculitis, ten cases of lichen planus (LP), and five cases of cutaneous drug reactions (including one case of erythema multiforme). In addition, we utilized 45 normal skin control specimens from plastic surgery reductions.Results:We found a 98% positive correlation between DIF and PAS staining patterns over all the disease samples.Conclusion:We recommend that laboratories without access to DIF always perform PAS staining in addition to hematoxylin and eosin (H&E) staining, for a review of the reactivity pattern.