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Gu Y, Merriman C, Guo Z, Jia X, Wenzlau J, Li H, Li H, Rewers M, Yu L, Fu D. Novel autoantibodies to the β-cell surface epitopes of ZnT8 in patients progressing to type-1 diabetes. J Autoimmun 2021; 122:102677. [PMID: 34130115 PMCID: PMC9029399 DOI: 10.1016/j.jaut.2021.102677] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2021] [Revised: 05/26/2021] [Accepted: 05/29/2021] [Indexed: 11/22/2022]
Abstract
Type 1 diabetes (T1D) is a chronic autoimmune disease characterized by autoimmune destruction of insulin-producing β-cells in pancreatic islets. Seroconversions to islet autoantibodies (IAbs) precede the disease onset by many years, but the role of humoral autoimmunity in the disease initiation and progression are unclear. In the present study, we identified a new IAb directed to the extracellular epitopes of ZnT8 (ZnT8ec) in newly diagnosed patients with T1D, and demonstrated immunofluorescence staining of the surface of human β-cells by autoantibodies to ZnT8ec (ZnT8ecA). With the assay specificity set on 99th percentile of 336 healthy controls, the ZnT8ecA positivity rate was 23.6% (74/313) in patients with T1D. Moreover, 30 children in a longitudinal follow up of clinical T1D development were selected for sequential expression of four major IAbs (IAA, GADA, IA-2A and ZnT8icA). Among them, 10 children were ZnT8ecA positive. Remarkably, ZnT8ecA was the earliest IAb to appear in all 10 children. The identification of ZnT8ec as a cell surface target of humoral autoimmunity in the earliest phase of IAb responses opens a new avenue of investigation into the role of IAbs in the development of β-cell autoimmunity.
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Affiliation(s)
- Yong Gu
- Barbara Davis Center for Diabetes University of Colorado School of Medicine, Aurora, CO, USA
| | - Chengfeng Merriman
- Department of Physiology, Johns Hopkins School of Medicine, Baltimore, MD, USA
| | - Zheng Guo
- Department of Physiology, Johns Hopkins School of Medicine, Baltimore, MD, USA
| | - Xiaofan Jia
- Barbara Davis Center for Diabetes University of Colorado School of Medicine, Aurora, CO, USA
| | - Janet Wenzlau
- Barbara Davis Center for Diabetes University of Colorado School of Medicine, Aurora, CO, USA
| | - Hua Li
- Department of Structural Biology, Van Andel Institute, Grand Rapids, MI, USA
| | - Huilin Li
- Department of Structural Biology, Van Andel Institute, Grand Rapids, MI, USA
| | - Marian Rewers
- Barbara Davis Center for Diabetes University of Colorado School of Medicine, Aurora, CO, USA
| | - Liping Yu
- Barbara Davis Center for Diabetes University of Colorado School of Medicine, Aurora, CO, USA.
| | - Dax Fu
- Department of Physiology, Johns Hopkins School of Medicine, Baltimore, MD, USA.
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Haskins K, Wenzlau J. Cluster of Differentiation 4 T Cells and Neoantigens in Autoimmune Diabetes. Crit Rev Immunol 2021; 40:441-446. [PMID: 33463955 DOI: 10.1615/critrevimmunol.2020034833] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Our investigations of antigens for pathogenic T cells in autoimmune diabetes led to the discovery of hybrid insulin peptides as T cell epitopes. T cells reactive to hybrid insulin peptides can be found at high frequency in the nonobese diabetic mouse model of type 1 diabetes and are also present in human patients. Hybrid insulin peptides can also be administered to mice in a tolerogenic form, thereby suppressing the autoimmune response.
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Affiliation(s)
- Kathryn Haskins
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, CO
| | - Janet Wenzlau
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, CO
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Lahner E, Marzinotto I, Brigatti C, Davidson H, Wenzlau J, Piemonti L, Annibale B, Lampasona V. Measurement of Autoantibodies to Gastric H+,K+-ATPase (ATP4A/B) Using a Luciferase Immunoprecipitation System (LIPS). Methods Mol Biol 2019; 1901:113-131. [PMID: 30539573 DOI: 10.1007/978-1-4939-8949-2_10] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
The Luciferase Immuno Precipitation System (LIPS) enables the detection of specific serum antibodies by immunoprecipitation of recombinant antigens tagged with a luciferase reporter. Here we describe LIPS assays for the quantification of autoantibodies to the H+, K+-ATPase A (ATP4A) and B (ATP4B) subunits, two serological markers of autoimmune atrophic gastritis and pernicious anemia. In particular, we will describe the expression of luciferase-tagged recombinant ATP4A and ATP4B, their immunoprecipitation with test sera, the recovery and washing of immune-complexes with a protein-A coated resin, and the quantification of autoantibodies by addition of a luciferase substrate and the measurement of the light output from captured luciferase-tagged antigens.
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Affiliation(s)
- Edith Lahner
- Medical-Surgical Department of Clinical Sciences and Translational Medicine, Sant'Andrea Hospital, Sapienza University of Rome, Rome, Italy
| | - Ilaria Marzinotto
- Division of Genetics and Cell Biology, IRCCS San Raffaele Scientific Institute, Milan, Italy
| | - Cristina Brigatti
- Beta Cell Biology Unit, Diabetes Research Institute, IRCCS San Raffaele Scientific Institute, Milan, Italy
| | - Howard Davidson
- Barbara Davis Center for Diabetes, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Janet Wenzlau
- Barbara Davis Center for Diabetes, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Lorenzo Piemonti
- Beta Cell Biology Unit, Diabetes Research Institute, IRCCS San Raffaele Scientific Institute, Milan, Italy
| | - Bruno Annibale
- Medical-Surgical Department of Clinical Sciences and Translational Medicine, Sant'Andrea Hospital, Sapienza University of Rome, Rome, Italy
| | - Vito Lampasona
- Division of Genetics and Cell Biology, IRCCS San Raffaele Scientific Institute, Milan, Italy.
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Chobot A, Rusak E, Wenzlau J, Davidson H, Adamczyk P, Krzywicka A, Mazur B, Polańska J, Rewers M. ATP4A autoimmunity in pediatric patients with type 1 diabetes and its relationship to blood count, iron metabolism, and vitamin B12. Pediatr Diabetes 2018; 19:80-84. [PMID: 28401620 DOI: 10.1111/pedi.12528] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/22/2016] [Revised: 03/06/2017] [Accepted: 03/17/2017] [Indexed: 12/22/2022] Open
Abstract
OBJECTIVE We aimed to assess the prevalence of autoantibodies against the 4A subunit of the gastric proton pump (ATP4A) in pediatric type 1 diabetes (T1D) patients and explore the relationship between ATP4A positivity and blood cell count, iron turnover, and vitamin B12 concentration. SUBJECTS The study included 94 (59% female) T1D children (aged 12.5 ± 4.1 years, T1D duration 4.2 ± 3.6 years, HbA1c 7.3 ± 1.5% (57 ± 12.6 mmol/mol) with no other autoimmune diseases. METHODS ATP4A antibodies were measured in T1D patients using a radioimmunoprecipitation assay. Blood cell count, iron concentration, total iron binding capacity, ferritin, transferrin, hepcidin, and vitamin B12 concentration were measured in all the study participants. RESULTS A total of 16 (17%) children were ATP4A positive. Serum concentrations of ferritin were significantly lower in ATP4A positive than in antibody negative subjects (P = .034). Overall the levels of ATP4A antibodies (ATP4A Index) correlated positively with the age at T1D diagnosis (r = 0.228, P = .026) and negatively with ferritin levels (r = -0.215, P = .037). In ATP4A positive patients, the ATP4A Index correlated positively with age at diagnosis (r = 0.544, P = .032) and negatively with vitamin B12 levels (r = -0.685, P = .004). CONCLUSIONS ATP4A antibodies were present in a significant proportion of children with T1D. Higher ATP4A levels in T1D children are associated with lower, yet still fitting within the normal range, levels of vitamin B12, and ferritin. Routine screening of T1D children for gastric autoimmunity (ATP4A) should be considered with follow-up of those positive for vitamin B12 and iron deficiency.
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Affiliation(s)
- Agata Chobot
- Public Clinical Hospital No. 1 in Zabrze, Zabrze, Poland
| | - Ewa Rusak
- The Upper Silesian Center for Child Health, Katowice, Poland
| | - Janet Wenzlau
- University of Colorado Denver, Barbara Davis Center for Diabetes, Aurora, Colorado
| | - Howard Davidson
- University of Colorado Denver, Barbara Davis Center for Diabetes, Aurora, Colorado
| | - Piotr Adamczyk
- School of Medicine with the Division of Dentistry in Zabrze, Medical University of Silesia, Katowice, Poland
| | | | - Bogdan Mazur
- School of Medicine with the Division of Dentistry in Zabrze, Medical University of Silesia, Katowice, Poland
| | | | - Marian Rewers
- University of Colorado Denver, Barbara Davis Center for Diabetes, Aurora, Colorado
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Rusak E, Chobot A, Krzywicka A, Wenzlau J. Anti-parietal cell antibodies - diagnostic significance. Adv Med Sci 2016; 61:175-179. [PMID: 26918709 DOI: 10.1016/j.advms.2015.12.004] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2015] [Revised: 12/30/2015] [Accepted: 12/31/2015] [Indexed: 02/07/2023]
Abstract
Anti-parietal cell antibodies (APCA) are an advantageous tool for screening for autoimmune atrophic gastritis (AAG) and pernicious anemia (PA). The target for APCA is the H+/K+ ATP-ase. It has been demonstrated, that APCA target both, the alpha, and beta subunits of the proton pump, although the major antigen is the alpha subunit. Circulating serum APCA can be detected by means of immunofluorescence, enzyme-linked immunosorbent assay - currently the most commonly used method, and radioimmunoprecipitation assay (RIA) - the 4A subunit has been optimized as a molecular-specific antigen probe. RIA is the most accurate method of antibody assessment, characterized by highest sensitivity. APCA can be found in 85-90% of patients with PA. Their presence is not sufficient for diagnosis, because they are not specific for PA as they are also found in the circulation of individuals with other diseases. APCA are more prevalent in the serum of patients with T1D, autoimmune thyroid diseases, vitiligo, celiac disease. People with autoimmune diseases should be closely screened for AAG/PA. The anemia develops longitudinally over many years in APCA-positive patients, symptomless, slowly promotes atrophy of the gastric mucosa and parietal cells. APCA are present in 7.8-19.5% of the general healthy adult population. A fraction of these sero-positive people, will never develop AAG or PA. An interesting and not fully explained question is whether APCA presence is related to Helicobacter pylori infection. APCA are found in up to 20.7% of these patients. H. pylori is implicated as one of the candidates causing AAG.
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Brorsson CA, Onengut S, Chen WM, Wenzlau J, Yu L, Baker P, Williams AJK, Bingley PJ, Hutton JC, Eisenbarth GS, Concannon P, Rich SS, Pociot F. Novel Association Between Immune-Mediated Susceptibility Loci and Persistent Autoantibody Positivity in Type 1 Diabetes. Diabetes 2015; 64:3017-27. [PMID: 25829454 PMCID: PMC4512221 DOI: 10.2337/db14-1730] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/11/2014] [Accepted: 03/26/2015] [Indexed: 12/25/2022]
Abstract
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), tissue transglutaminase, and 21-hydroxylase was tested using a linear mixed-model regression approach to simultaneously control for population structure and family relatedness. Four loci were associated with autoantibody positivity at genome-wide significance. Positivity for GADA was associated with 3q28/LPP, for IA-2A with 1q23/FCRL3 and 11q13/RELA, and for PCAs with 2q24/IFIH1. The 3q28 locus showed association after only 3 years duration and might therefore be a marker of persistent GADA positivity. The 1q23, 11q13, and 2q24 loci were associated with autoantibodies close to diabetes onset 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.
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Affiliation(s)
| | - Suna Onengut
- Division of Endocrinology, Department of Medicine, University of Virginia, Charlottesville, VA Center for Public Health Genomics, University of Virginia, Charlottesville, VA
| | - Wei-Min Chen
- Center for Public Health Genomics, University of Virginia, Charlottesville, VA Department of Public Health Sciences, Division of Biostatistics and Epidemiology, University of Virginia, Charlottesville, VA
| | - Janet Wenzlau
- Barbara Davis Center for Childhood Diabetes, University of Colorado School of Medicine, Aurora, CO
| | - Liping Yu
- Barbara Davis Center for Childhood Diabetes, University of Colorado School of Medicine, Aurora, CO
| | - Peter Baker
- Barbara Davis Center for Childhood Diabetes, University of Colorado School of Medicine, Aurora, CO
| | - Alistair J K Williams
- Diabetes & Metabolism, School of Clinical Sciences, University of Bristol, Bristol, U.K
| | - Polly J Bingley
- Diabetes & Metabolism, School of Clinical Sciences, University of Bristol, Bristol, U.K
| | - John C Hutton
- Barbara Davis Center for Childhood Diabetes, University of Colorado School of Medicine, Aurora, CO
| | - George S Eisenbarth
- Barbara Davis Center for Childhood Diabetes, University of Colorado School of Medicine, Aurora, CO
| | - Patrick Concannon
- Genetics Institute and Department of Pathology, Immunology and Laboratory Medicine, University of Florida, Gainesville, FL
| | - Stephen S Rich
- Center for Public Health Genomics, University of Virginia, Charlottesville, VA Department of Public Health Sciences, Division of Biostatistics and Epidemiology, University of Virginia, Charlottesville, VA
| | - Flemming Pociot
- Department of Pediatrics, Herlev University Hospital, Herlev, Denmark
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Chobot A, Wenzlau J, Bak-Drabik K, Kwiecien J, Polanska J, Rewers M. ATP4A autoimmunity and Helicobacter pylori infection in children with type 1 diabetes. Clin Exp Immunol 2014; 177:598-602. [PMID: 24773566 DOI: 10.1111/cei.12363] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/17/2014] [Indexed: 12/20/2022] Open
Abstract
Persistent presence of ATP4A autoantibodies (ATP4AA) directed towards parietal cells is typical for atrophic body gastritis (ABG), an autoimmune disease associated with type 1 diabetes. We assessed whether Helicobacter pylori (Hp) infection might be associated with positivity for ATP4AA in children with type 1 diabetes. Sera were collected from 70 (38♀) type 1 diabetes children [aged 13·2 ± 4·5 years, age at diagnosis 8·8 ± 4·3 years, diabetes duration 4·5 ± 3·8 years, mean HbA1c 7·8 ± 1·6% (62 ± 17·5 mmol/mol)] seen at the regional diabetes clinic in Katowice, Poland. Patients were tested concurrently for Hp infection by means of a 13C urea breath test. ATP4AA were measured using a novel radioimmunoprecipitation assay developed at the Barbara Davies Center for Childhood Diabetes, University of Colorado. ATP4AA were present in 21 [30%, 95% confidence interval (CI) = 19-41%] and Hp infection was detected in 23 (33%, 95% CI = 22-44%) children. There was no statistically significant association between ATP4AA presence and Hp status. ATP4AA presence was not associated with current age, age at type 1 diabetes diagnosis, diabetes duration or current HbA1c. ATP4AA were more prevalent in females [42% (26-58%)] than males [16% (3-28%)], P = 0·016. ATP4A are found in nearly one-third of children with type 1 diabetes and more common among females. In this cross-sectional analysis, Hp infection was not associated with autoimmunity against parietal cells.
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Affiliation(s)
- A Chobot
- Clinical Hospital No1, Zabrze, Poland
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Baker P, Fain P, Kahles H, Yu L, Hutton J, Wenzlau J, Rewers M, Badenhoop K, Eisenbarth G. Genetic determinants of 21-hydroxylase autoantibodies amongst patients of the Type 1 Diabetes Genetics Consortium. J Clin Endocrinol Metab 2012; 97:E1573-8. [PMID: 22723331 PMCID: PMC3410257 DOI: 10.1210/jc.2011-2824] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
BACKGROUND Autoantibodies to 21-hydroxylase (21OH-AA) precede the onset of autoimmune Addison's disease (AD) and are found in 1.5% of individuals with type 1 diabetes mellitus (T1DM). The greatest genetic risk for both disorders is found in the major histocompatibility complex (MHC), suggesting a common pathophysiology between AD and T1DM. Screening for 21OH-AA in newly diagnosed T1DM patients is a valuable prognostic tool, made stronger when MHC genotype is considered. METHODS The Type 1 Diabetes Genetics Consortium has collected genotype data in T1DM subjects with tissue-specific autoantibody typing. Genotype and phenotype data in individuals positive and negative for 21OH-AA are compared. RESULTS Major genetic risk for 21OH-AA is in the MHC haplotypes DRB1*04-DQB1*0302 (primarily DRB1*0404) and DRB1*0301-DQB1*0201. Protective effects in class II MHC haplotypes DRB1*0101-DQB1*0501 and DRB1*0701-DQB1*0202 also were detected. There is no difference in the presence of HLA-B15 and little difference in the presence of HLA-B8 (after class II effects are accounted for) in T1DM patients with 21OH-AA compared with known associations (HLA-B8 positive and HLA-B15 negative) in AD. CONCLUSIONS In 21OH-AA(+) subjects, genetic risk is found mainly in MHC class II haplotypes DR3 and DR4 but not class I alleles (HLA-B8 or HLA-B15). This suggests a difference between autoantibody formation (class II dependent) and progression to overt disease (class I dependent) in AD.
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Affiliation(s)
- Peter Baker
- Barbara Davis Center for Childhood Diabetes, Aurora, Colorado 80045, USA
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Gottlieb PA, Yu L, Babu S, Wenzlau J, Bellin M, Frohnert BI, Moran A. No relation between cystic fibrosis-related diabetes and type 1 diabetes autoimmunity. Diabetes Care 2012; 35:e57. [PMID: 22826450 PMCID: PMC3402258 DOI: 10.2337/dc11-2327] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Affiliation(s)
- Peter A. Gottlieb
- From the Barbara Davis Center for Childhood Diabetes, University of Colorado Health Sciences Center, Denver, Colorado; and the
| | - Liping Yu
- From the Barbara Davis Center for Childhood Diabetes, University of Colorado Health Sciences Center, Denver, Colorado; and the
| | - Sunanda Babu
- From the Barbara Davis Center for Childhood Diabetes, University of Colorado Health Sciences Center, Denver, Colorado; and the
| | - Janet Wenzlau
- From the Barbara Davis Center for Childhood Diabetes, University of Colorado Health Sciences Center, Denver, Colorado; and the
| | - Melena Bellin
- Department of Pediatrics, University of Minnesota, Minneapolis, Minnesota
| | | | - Antoinette Moran
- Department of Pediatrics, University of Minnesota, Minneapolis, Minnesota
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Vermeulen I, Weets I, Costa O, Asanghanwa M, Verhaeghen K, Decochez K, Ruige J, Casteels K, Wenzlau J, Hutton JC, Pipeleers DG, Gorus FK. An important minority of prediabetic first-degree relatives of type 1 diabetic patients derives from seroconversion to persistent autoantibody positivity after 10 years of age. Diabetologia 2012; 55:413-20. [PMID: 22095238 PMCID: PMC3810367 DOI: 10.1007/s00125-011-2376-1] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/08/2011] [Accepted: 10/14/2011] [Indexed: 10/15/2022]
Abstract
AIMS/HYPOTHESIS The appearance of autoantibodies (Abs) before diabetes onset has mainly been studied in young children. However, most patients develop type 1 diabetes after the age of 15 years. In first-degree relatives aged under 40 years, we investigated the frequency of seroconversion to (persistent) Ab positivity, progression to diabetes and baseline characteristics of seroconverters according to age. METHODS Abs against insulin (IAA), glutamate decarboxylase (GADA), insulinoma-associated protein 2 (IA-2A) and zinc transporter 8 (ZnT8A) were measured during follow-up of 7,170 first-degree relatives. RESULTS We identified 379 (5.3%) relatives with positivity for IAA, GADA, IA-2A and/or ZnT8A (Ab(+)) at first sampling and 224 (3.1%) at a later time point. Most seroconversions occurred after the age of 10 years (63%). During follow-up, Abs persisted more often in relatives initially Ab(+) (76%) than in seroconverters (53%; p < 0.001). In both groups diabetes developed at a similar pace and almost exclusively with Ab persistence (136 of 139 prediabetic individuals). For both groups, progression was more rapid if Abs appeared before the age of 10 years. Baseline characteristics at seroconversion did not vary significantly according to age. CONCLUSIONS/INTERPRETATION Seroconversion to (persistent) Ab(+) occurs regardless of age. Although the progression rate to diabetes is higher under age 10 years, later seroconverters (up to age 40 years) have similar characteristics when compared with age-matched initially Ab(+) relatives and generate an important minority of prediabetic relatives, warranting their identification and, eventually, enrolment in prevention trials.
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Affiliation(s)
- I Vermeulen
- Diabetes Research Center, Brussels Free University, VUB, Laarbeeklaan 103, 1090 Brussels, Belgium
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De Grijse J, Asanghanwa M, Nouthe B, Albrecher N, Goubert P, Vermeulen I, Van Der Meeren S, Decochez K, Weets I, Keymeulen B, Lampasona V, Wenzlau J, Hutton JC, Pipeleers D, Gorus FK. Predictive power of screening for antibodies against insulinoma-associated protein 2 beta (IA-2beta) and zinc transporter-8 to select first-degree relatives of type 1 diabetic patients with risk of rapid progression to clinical onset of the disease: implications for prevention trials. Diabetologia 2010; 53:517-24. [PMID: 20091020 DOI: 10.1007/s00125-009-1618-y] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/08/2009] [Accepted: 11/05/2009] [Indexed: 02/04/2023]
Abstract
AIMS/HYPOTHESIS We investigated whether screening for insulinoma-associated protein (IA-2) beta (IA-2beta) autoantibodies (IA-2betaA) and zinc transporter-8 (ZnT8) autoantibodies (ZnT8A) improves identification of first-degree relatives of type 1 diabetic patients with a high 5-year disease risk, which to date has been based on assays for insulin autoantibodies (IAA), GAD autoantibodies (GADA) and IA-2 autoantibodies (IA-2A). METHODS IA-2betaA and ZnT8A (using a ZnT8 carboxy-terminal hybrid construct, CW-CR, carrying 325Arg and 325Trp) were determined by radiobinding assay in 409 IAA(+), GADA(+) and/or IA-2A(+) siblings or offspring (<40 years) of type 1 diabetic patients consecutively recruited by the Belgian Diabetes Registry. The median (interquartile range) age of the first-degree relatives was 12 (6-19) years. RESULTS Of the first-degree relatives, 24% were IA-2A(+) (n = 97), 14% (n = 59) IA-2betaA(+) and 20% (n = 80) ZnT8A(+). IA-2betaA and ZnT8A were significantly (p < 0.001) associated with IA-2A and prediabetes (n = 86); in IA-2A(-) first-degree relatives (n = 312) the presence of IA-2betaA and ZnT8A was associated with an increased progression rate to diabetes (p < 0.001). Positivity for IA-2A and/or ZnT8A emerged as the most sensitive combination of two markers to identify first-degree relatives with a 5-year progression rate to diabetes of 45% (survival analysis) and as strongest predictor of diabetes (Cox regression analysis). Omission of first-degree relatives protected by HLA-DQ genotypes or maternal diabetes reduced the group to be followed from n = 409 to n = 246 (40%) with minor loss in the number of prediabetic IA-2A(+) or ZnT8A(+) first-degree relatives identified (n = 3). CONCLUSIONS/INTERPRETATION IA-2A(+) and/or ZnT8A(+) first-degree relatives may be the participants of choice in future secondary prevention trials with immunointervention in relatives of type 1 diabetic patients.
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Affiliation(s)
- J De Grijse
- Diabetes Research Center, Brussels Free University-VUB, Laarbeeklaan 103, B-1090 Brussels, Belgium
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Yu L, Liu Y, Miao D, Wenzlau J, Davidson H, Hutton J, Eisenbarth GS. Triple chimeric islet autoantigen IA2-ZnT8WR to facilitate islet autoantibody determination. J Immunol Methods 2009; 353:20-3. [PMID: 20035758 DOI: 10.1016/j.jim.2009.12.004] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2009] [Revised: 08/20/2009] [Accepted: 12/10/2009] [Indexed: 11/25/2022]
Abstract
Type 1A diabetes is strongly associated with the presence of islet autoantibodies. Large scale population screening of islet autoantibodies is essential for many different national and international studies related to defining subtypes of diabetes, the natural history of the disease, and for trials of prevention. Testing for relevant autoantibodies has become more difficult as the number of important autoantibodies/epitopes increases. In the present study, we created a chimeric protein, IA2-ZnT8WR, with two major islet autoantigens, IA-2 and the recent Zinc transporter 8 (ZnT8). The chimeric molecule included both common polymorphisms of the ZnT8 molecule, arginine or tryptophan at position 325. Serum samples from 284 patients with newly diagnosed diabetes, 10 prediabetics, and 110 age-matched normal controls were analyzed for islet autoantibodies reacting with the IA2-ZnT8WR molecule. Autoantibodies to the chimeric molecule were compared to reactivity with individual assays detecting autoantibodies reacting with the separate molecules (IA-2, ZnT8-R and ZnT8-W). With this chimeric protein antigen, IA2-ZnT8WR, one radioassay is able to detect autoantibodies to IA-2 and to both major forms of ZnT8 (100% sensitivity, 100% unchanged specificity, relative to individual molecules). The chimeric assay provides an efficient and economical technique to screen for islet autoantibodies reacting with IA-2 and ZnT8.
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Affiliation(s)
- Liping Yu
- Barbara Davis Center for Childhood Diabetes, University of Colorado Denver, Aurora, CO, United States
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