1
|
Erdei E, O'Donald ER, Luo L, Enright K, O'Leary M, MacKenzie D, Doyle J, Eggers M, Keil D, Lewis J, Henderson JA, Rubin RL. Comparison of circulating and excreted metals and of autoimmunity between two Great Plains Tribal communities. J Autoimmun 2023:103117. [PMID: 37813804 PMCID: PMC10998922 DOI: 10.1016/j.jaut.2023.103117] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Revised: 09/17/2023] [Accepted: 09/19/2023] [Indexed: 10/11/2023]
Abstract
Metals contaminants of the environment from mine waste have been implicated as contributing agents in autoimmune disease. The current study compares metals and autoimmunity in two Tribal communities residing in the Black Hills and the Bighorn Mountains geographical regions that are scattered with extant hard rock mines. With documented drinking water contamination in both communities, in vivo levels of more than half of the measured serum and urine metals differed between the two communities and were substantially different from their national median values. Serum autoantibodies associated with systemic autoimmune disease were rare or at low-level, but antibodies to denatured (single-stranded) DNA and thyroid-specific autoantibodies were commonly elevated, especially in women. A three-tier statistical modeling process was carried out to examine individual metals exposure as predictors of autoantibody levels. For the most part only weak positive associations between individual metals and systemic autoantibodies were found, although univariate quantile regression analysis showed positive statistical associations of serum lead and antimony with anti-chromatin and anti-histone autoantibodies. Using age and gender-adjusted multivariable statistical models, metals did not predict anti-thyroglobulin or -thyroid peroxidase significantly and metals were generally negative predictors of the other autoantibodies. Overall these results suggest that elevated levels of environmental metals and metalloids in these communities may result in suppression of autoantibodies associated with systemic autoimmune disease.
Collapse
Affiliation(s)
- Esther Erdei
- Community Environmental Health Program, Dept. of Pharmaceutical Sciences, College of Pharmacy, University of New Mexico, Health Sciences Center, Albuquerque, NM, USA.
| | - Elena R O'Donald
- Community Environmental Health Program, Dept. of Pharmaceutical Sciences, College of Pharmacy, University of New Mexico, Health Sciences Center, Albuquerque, NM, USA
| | - Li Luo
- Community Environmental Health Program, Dept. of Pharmaceutical Sciences, College of Pharmacy, University of New Mexico, Health Sciences Center, Albuquerque, NM, USA; University of New Mexico, Health Sciences Center UNM Comprehensive Cancer Center, Albuquerque, NM, USA
| | - Kendra Enright
- Missouri Breaks Industries Research Inc. Eagle Butte, SD, USA
| | - Marcia O'Leary
- Missouri Breaks Industries Research Inc. Eagle Butte, SD, USA
| | - Debra MacKenzie
- Community Environmental Health Program, Dept. of Pharmaceutical Sciences, College of Pharmacy, University of New Mexico, Health Sciences Center, Albuquerque, NM, USA
| | - John Doyle
- Crow Environmental Health Steering Committee, Little Big Horn College, Crow Agency, MT, USA
| | - Margaret Eggers
- Crow Environmental Health Steering Committee, Little Big Horn College, Crow Agency, MT, USA; Montana State University, Bozeman, MT, USA
| | | | - Johnnye Lewis
- Community Environmental Health Program, Dept. of Pharmaceutical Sciences, College of Pharmacy, University of New Mexico, Health Sciences Center, Albuquerque, NM, USA
| | | | - Robert L Rubin
- University of New Mexico, Health Sciences Center, School of Medicine, Dept. of Molecular Genetics and Microbiology, Albuquerque, NM, USA
| |
Collapse
|
2
|
Sabljic AV, Bombicino SS, Marfía JI, Guerra LL, Steinhardt AP, Faccinetti NI, Iacono RF, Poskus E, Trabucchi A, Valdez SN. Novel Flow Cytometric Immunoassay for Detection of Proinsulin Autoantibodies in Diabetes Mellitus Employing a Recombinant Autoantigen Expressed in E. coli. Front Immunol 2021; 12:648021. [PMID: 33889155 PMCID: PMC8056981 DOI: 10.3389/fimmu.2021.648021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Accepted: 03/17/2021] [Indexed: 11/13/2022] Open
Abstract
Introduction Insulin and proinsulin autoantibodies (IAA/PAA) are usually the first markers to appear in patients with type 1 Diabetes Mellitus (T1DM) and their prevalence ranges from 10 to 60% in the child-adolescent population. The reference method for IAA/PAA detection is the Radioligand Binding Assay (RBA), a highly specific and sensitive technique, but expensive and polluting. The aim of this work was to develop a novel flow cytometric microsphere-based immunoassay (FloCMIA) for PAA detection, employing recombinant human proinsulin (PI), as an alternative method to RBA, less expensive and harmful to the environment. Materials and Methods Human PI was expressed as Thioredoxin fusion protein (TrxPI) in E. coli and a fraction was biotinylated. A double paratope model was used in which samples were incubated with TrxPI-biotin and microspheres adsorbed with TrxPI. The immune complexes were revealed using Streptavidin-Phycoerythrin. The geometric mean of the signals was analyzed, and the results were expressed as Standard Deviation scores (SDs). Sera from 100 normal human control and from 111 type 1 diabetic patients were evaluated by FloCMIA. To correlate the novel assay with RBA, 51 diabetic patients were selected, spanning a wide range of PAA reactivity by RBA. Results The study of ROC curves allowed choosing a cut-off value of 3.0 SDs and the AUC was 0.705, indicating that FloCMIA has fair ability to distinguish between samples from each group. A prevalence of 50% for PAA was obtained in the population of diabetic patients studied. The specificity was 96% and the analytical sensitivity (percentage of patients RBA positive, also positive by FloCMIA) was 69%. There was a substantial agreement between methods (kappa statistic=0.700). Conclusions A novel immunoassay based on flow cytometry that uses easy-to produce recombinant PI was developed. This assay constitutes an innovative and cost-effective alternative to RBA for the determination of PAA in patients' sera. The method developed here, presents good performance and a wide dynamic range together with a small required sample volume. Furthermore, these results make it possible to develop multiplex immunoassays that allow the combined detection of autoantibodies present in T1DM and other related autoimmune diseases.
Collapse
Affiliation(s)
- Adriana Victoria Sabljic
- Universidad de Buenos Aires (UBA), Facultad de Farmacia y Bioquímica, Departamento de Microbiología, Inmunología, Biotecnología y Genética, Cátedra de Inmunología, Buenos Aires, Argentina
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) Universidad de Buenos Aires, Instituto de Estudios de la Inmunidad Humoral “Prof. Ricardo A. Margni” (IDEHU), Buenos Aires, Argentina
| | - Silvina Sonia Bombicino
- Universidad de Buenos Aires (UBA), Facultad de Farmacia y Bioquímica, Departamento de Microbiología, Inmunología, Biotecnología y Genética, Cátedra de Inmunología, Buenos Aires, Argentina
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) Universidad de Buenos Aires, Instituto de Estudios de la Inmunidad Humoral “Prof. Ricardo A. Margni” (IDEHU), Buenos Aires, Argentina
| | - Juan Ignacio Marfía
- Universidad de Buenos Aires (UBA), Facultad de Farmacia y Bioquímica, Departamento de Microbiología, Inmunología, Biotecnología y Genética, Cátedra de Inmunología, Buenos Aires, Argentina
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) Universidad de Buenos Aires, Instituto de Estudios de la Inmunidad Humoral “Prof. Ricardo A. Margni” (IDEHU), Buenos Aires, Argentina
| | - Luciano Lucas Guerra
- Universidad de Buenos Aires (UBA), Facultad de Farmacia y Bioquímica, Departamento de Microbiología, Inmunología, Biotecnología y Genética, Cátedra de Inmunología, Buenos Aires, Argentina
| | - Alberto Penas Steinhardt
- Universidad Nacional de Lujan, Departamento de Ciencias Básicas, Laboratorio de Genómica Computacional, Buenos Aires, Argentina
| | - Natalia Inés Faccinetti
- Universidad de Buenos Aires (UBA), Facultad de Farmacia y Bioquímica, Departamento de Microbiología, Inmunología, Biotecnología y Genética, Cátedra de Inmunología, Buenos Aires, Argentina
| | - Rubén Francisco Iacono
- Universidad de Buenos Aires (UBA), Facultad de Farmacia y Bioquímica, Departamento de Microbiología, Inmunología, Biotecnología y Genética, Cátedra de Inmunología, Buenos Aires, Argentina
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) Universidad de Buenos Aires, Instituto de Estudios de la Inmunidad Humoral “Prof. Ricardo A. Margni” (IDEHU), Buenos Aires, Argentina
| | - Edgardo Poskus
- Universidad de Buenos Aires (UBA), Facultad de Farmacia y Bioquímica, Departamento de Microbiología, Inmunología, Biotecnología y Genética, Cátedra de Inmunología, Buenos Aires, Argentina
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) Universidad de Buenos Aires, Instituto de Estudios de la Inmunidad Humoral “Prof. Ricardo A. Margni” (IDEHU), Buenos Aires, Argentina
| | - Aldana Trabucchi
- Universidad de Buenos Aires (UBA), Facultad de Farmacia y Bioquímica, Departamento de Microbiología, Inmunología, Biotecnología y Genética, Cátedra de Inmunología, Buenos Aires, Argentina
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) Universidad de Buenos Aires, Instituto de Estudios de la Inmunidad Humoral “Prof. Ricardo A. Margni” (IDEHU), Buenos Aires, Argentina
| | - Silvina Noemí Valdez
- Universidad de Buenos Aires (UBA), Facultad de Farmacia y Bioquímica, Departamento de Microbiología, Inmunología, Biotecnología y Genética, Cátedra de Inmunología, Buenos Aires, Argentina
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) Universidad de Buenos Aires, Instituto de Estudios de la Inmunidad Humoral “Prof. Ricardo A. Margni” (IDEHU), Buenos Aires, Argentina
| |
Collapse
|
3
|
Hu X, Chen F. Exogenous insulin antibody syndrome (EIAS): a clinical syndrome associated with insulin antibodies induced by exogenous insulin in diabetic patients. Endocr Connect 2018; 7:R47-R55. [PMID: 29233817 PMCID: PMC5776673 DOI: 10.1530/ec-17-0309] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/01/2017] [Accepted: 12/12/2017] [Indexed: 11/11/2022]
Abstract
Insulin has been used for diabetes therapy and has achieved significant therapeutic effect. In recent years, the use of purified and recombinant human insulin preparations has markedly reduced, but not completely suppressed, the incidence of insulin antibodies (IAs). IAs induced by exogenous insulin in diabetic patients is associated with clinical events, which is named exogenous insulin antibody syndrome (EIAS). The present review is based on our research and summarizes the characterization of IAs, the factors affecting IA development, the clinical significance of IAs and the treatments for EIAS.
Collapse
Affiliation(s)
- Xiaolei Hu
- Department of EndocrinologyThe First Affiliated Hospital of Bengbu Medical College, Bengbu, Anhui, China
- Department of EndocrinologyShanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Fengling Chen
- Department of EndocrinologyShanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| |
Collapse
|
4
|
Guerra LL, Faccinetti NI, Trabucchi A, Rovitto BD, Sabljic AV, Poskus E, Iacono RF, Valdez SN. Novel prokaryotic expression of thioredoxin-fused insulinoma associated protein tyrosine phosphatase 2 (IA-2), its characterization and immunodiagnostic application. BMC Biotechnol 2016; 16:84. [PMID: 27881117 PMCID: PMC5122161 DOI: 10.1186/s12896-016-0309-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2016] [Accepted: 10/21/2016] [Indexed: 11/11/2022] Open
Abstract
Background The insulinoma associated protein tyrosine phosphatase 2 (IA-2) is one of the immunodominant autoantigens involved in the autoimmune attack to the beta-cell in Type 1 Diabetes Mellitus. In this work we have developed a complete and original process for the production and recovery of the properly folded intracellular domain of IA-2 fused to thioredoxin (TrxIA-2ic) in Escherichia coli GI698 and GI724 strains. We have also carried out the biochemical and immunochemical characterization of TrxIA-2icand design variants of non-radiometric immunoassays for the efficient detection of IA-2 autoantibodies (IA-2A). Results The main findings can be summarized in the following statements: i) TrxIA-2ic expression after 3 h of induction on GI724 strain yielded ≈ 10 mg of highly pure TrxIA-2ic/L of culture medium by a single step purification by affinity chromatography, ii) the molecular weight of TrxIA-2ic (55,358 Da) could be estimated by SDS-PAGE, size exclusion chromatography and mass spectrometry, iii) TrxIA-2ic was properly identified by western blot and mass spectrometric analysis of proteolytic digestions (63.25 % total coverage), iv) excellent immunochemical behavior of properly folded full TrxIA-2ic was legitimized by inhibition or displacement of [35S]IA-2 binding from IA-2A present in Argentinian Type 1 Diabetic patients, v) great stability over time was found under proper storage conditions and vi) low cost and environmentally harmless ELISA methods for IA-2A assessment were developed, with colorimetric or chemiluminescent detection. Conclusions E. coli GI724 strain emerged as a handy source of recombinant IA-2ic, achieving high levels of expression as a thioredoxin fusion protein, adequately validated and applicable to the development of innovative and cost-effective immunoassays for IA-2A detection in most laboratories. Electronic supplementary material The online version of this article (doi:10.1186/s12896-016-0309-2) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Luciano Lucas Guerra
- Universidad de Buenos Aires, Consejo Nacional de Investigaciones Científicas y Técnicas, Instituto de Estudios de la Inmunidad Humoral "Prof. Ricardo A. Margni" (IDEHU), Facultad de Farmacia y Bioquímica, Buenos Aires, Argentina
| | - Natalia Inés Faccinetti
- Universidad de Buenos Aires, Consejo Nacional de Investigaciones Científicas y Técnicas, Instituto de Estudios de la Inmunidad Humoral "Prof. Ricardo A. Margni" (IDEHU), Facultad de Farmacia y Bioquímica, Buenos Aires, Argentina
| | - Aldana Trabucchi
- Universidad de Buenos Aires, Consejo Nacional de Investigaciones Científicas y Técnicas, Instituto de Estudios de la Inmunidad Humoral "Prof. Ricardo A. Margni" (IDEHU), Facultad de Farmacia y Bioquímica, Buenos Aires, Argentina
| | - Bruno David Rovitto
- Universidad de Buenos Aires, Consejo Nacional de Investigaciones Científicas y Técnicas, Instituto de Estudios de la Inmunidad Humoral "Prof. Ricardo A. Margni" (IDEHU), Facultad de Farmacia y Bioquímica, Buenos Aires, Argentina
| | - Adriana Victoria Sabljic
- Universidad de Buenos Aires, Consejo Nacional de Investigaciones Científicas y Técnicas, Instituto de Estudios de la Inmunidad Humoral "Prof. Ricardo A. Margni" (IDEHU), Facultad de Farmacia y Bioquímica, Buenos Aires, Argentina
| | - Edgardo Poskus
- Universidad de Buenos Aires, Consejo Nacional de Investigaciones Científicas y Técnicas, Instituto de Estudios de la Inmunidad Humoral "Prof. Ricardo A. Margni" (IDEHU), Facultad de Farmacia y Bioquímica, Buenos Aires, Argentina
| | - Ruben Francisco Iacono
- Universidad de Buenos Aires, Consejo Nacional de Investigaciones Científicas y Técnicas, Instituto de Estudios de la Inmunidad Humoral "Prof. Ricardo A. Margni" (IDEHU), Facultad de Farmacia y Bioquímica, Buenos Aires, Argentina
| | - Silvina Noemí Valdez
- Universidad de Buenos Aires, Consejo Nacional de Investigaciones Científicas y Técnicas, Instituto de Estudios de la Inmunidad Humoral "Prof. Ricardo A. Margni" (IDEHU), Facultad de Farmacia y Bioquímica, Buenos Aires, Argentina.
| |
Collapse
|
5
|
Cardoso Landaburu A, Pomares M, Avalos A, Lapertosa S, Frechtel G, Poskus E. Use of cross-reactivity immunoassay to orient insulin replacement in diabetic patients with high levels of insulin antibodies. MethodsX 2016; 3:502-7. [PMID: 27617231 PMCID: PMC5007476 DOI: 10.1016/j.mex.2016.08.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2015] [Accepted: 08/02/2016] [Indexed: 12/01/2022] Open
Abstract
The prevalence and high levels of anti-insulin antibodies (IA) have frequently been associated with brittle diabetes, lipodystrophy in the areas where the insulin is injected and/or poor metabolic control. When this happens the usual criterion adopted is the empirical change of insulin type and/or formulation intending to diminish the IA level and then to decrease the undesirable side-effects. Here, we present a rational two step radiometric method consisting in: A) a first-line radioligand binding assay (RBA) to assess IA in sera of these patients and detecting those with high levels. B) applying a displacement assay (RIA) to determine the in vitro cross-reactivity parameters (affinity constants and selectivity ratios) that quantify the relative degree of interaction between antibodies and alternative insulin analogs. From these results we conclude that conventional criteria for selection of insulin analogs, in terms of pharmacokinetic and pharmacodinamic parameters, should be complemented with an appropriate test to assess affinity parameters when high IA title is demonstrated. •This manuscript introduces a rational method to determine the appropriated insulin replacement when high insulin antibodies levels are present.•This protocol provides instructions and details in mathematical tools and laboratory processes for the analysis of serum samples.•This method proved to be successful in a single case and requires confirmation using a large group of patients.
Collapse
Affiliation(s)
- Alejandro Cardoso Landaburu
- Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Cátedra de Inmunología-IDEHU (UBA-CONICET), Buenos Aires, Junín 956, CABA, CP C1113AAD, Argentina
| | - María Pomares
- Servicio de Endocrinología y Diabetes del Hospital Juan Pablo II, San Martin 569 Corrientes Capital CP 3400, Argentina
| | - Alfredo Avalos
- Servicio de Endocrinología, Nutrición y Diabetes, Hospital J. R. Vidal, Necochea 1050, Corrientes Capital CP 3400, Argentina
| | - Silvia Lapertosa
- Servicio de Endocrinología, Nutrición y Diabetes, Hospital J. R. Vidal, Necochea 1050, Corrientes Capital CP 3400, Argentina
| | - Gustavo Frechtel
- Servicio de Nutrición, Departamento de Medicina, Facultad de Medicina, Universidad de Buenos Aires (UBA), Paraguay 2155, CABA C1121ABG, Argentina
| | - Edgardo Poskus
- Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Cátedra de Inmunología-IDEHU (UBA-CONICET), Buenos Aires, Junín 956, CABA, CP C1113AAD, Argentina
| |
Collapse
|
6
|
Guerra LL, Trabucchi A, Faccinetti NI, Iacono RF, Ureta DB, Poskus E, Valdez SN. Flow cytometric microsphere-based immunoassay as a novel non-radiometric method for the detection of glutamic acid decarboxylase autoantibodies in type 1 diabetes mellitus. Analyst 2015; 139:3017-25. [PMID: 24783226 DOI: 10.1039/c3an02243a] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The first measurable sign of arising autoimmunity in type 1 diabetes mellitus is the detection of autoantibodies against beta-cell antigens, such as glutamic acid decarboxylase (GAD65). GAD65 autoantibodies (GADA) are usually measured by the Radioligand Binding Assay (RBA). The aim of this work was to develop protocols of flow cytometric microsphere-based immunoassays (FloCMIA) which involved glutamic acid decarboxylase fused to thioredoxin (TrxGAD65) adsorbed on polystyrene microspheres. Detection of bound GADA was accomplished by the use of anti-human IgG-Alexa Fluor 488 (protocol A), anti-human IgG-biotin and streptavidin-dichlorotriazinyl aminofluorescein (DTAF) (protocol B) or TrxGAD65-biotin and streptavidin-DTAF (protocol C). Serum samples obtained from 46 patients assayed for routine autoantibodies at Servicios Tecnológicos de Alto Nivel (STAN-CONICET) were analyzed by RBA, ELISA and three alternative FloCMIA designs. Protocol C exhibited the highest specificity (97.8%) and sensitivity (97.4%) and a wide dynamic range (1.00-134.40 SDs). Samples obtained from 40 new-onset diabetic patients were also analyzed to further evaluate the performance of protocol C. The latter protocol showed a sensitivity of 58.6% and a prevalence of 47.5%. Two patients resulted positive only by FloCMIA protocol C and its SDs were higher than those of RBA and ELISA, showing a significantly wide dynamic range. In conclusion, FloCMIA proved to be highly sensitive and specific, requiring a low sample volume; it is environmentally adequate, innovative and represents a cost-effective alternative to traditional GADA determination by RBA and/or ELISA, making it applicable to most medium-complexity laboratories.
Collapse
Affiliation(s)
- Luciano L Guerra
- Chair of Immunology, School of Pharmacy and Biochemistry, University of Buenos Aires (UBA), Humoral Immunity Institute Prof. Ricardo A. Margni (IDEHU), National Research Council (CONICET-UBA), Junín 956, C1113AAD, Buenos Aires, Argentina.
| | | | | | | | | | | | | |
Collapse
|
7
|
Villalba A, Iacono RF, Valdez SN, Poskus E. Detection and immunochemical characterization of glutamic acid decarboxylase autoantibodies in patients with autoimmune diabetes mellitus. Autoimmunity 2009; 41:143-53. [DOI: 10.1080/08916930701783338] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
|
8
|
Fineberg SE, Kawabata TT, Finco-Kent D, Fountaine RJ, Finch GL, Krasner AS. Immunological responses to exogenous insulin. Endocr Rev 2007; 28:625-52. [PMID: 17785428 DOI: 10.1210/er.2007-0002] [Citation(s) in RCA: 119] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Regardless of purity and origin, therapeutic insulins continue to be immunogenic in humans. However, severe immunological complications occur rarely, and less severe events affect a small minority of patients. Insulin autoantibodies (IAAs) may be detectable in insulin-naive individuals who have a high likelihood of developing type 1 diabetes or in patients who have had viral disorders, have been treated with various drugs, or have autoimmune disorders or paraneoplastic syndromes. This suggests that under certain circumstances, immune tolerance to insulin can be overcome. Factors that can lead to more or less susceptibility to humoral responses to exogenous insulin include the recipient's immune response genes, age, the presence of sufficient circulating autologous insulin, and the site of insulin delivery. Little proof exists, however, that the development of insulin antibodies (IAs) to exogenous insulin therapy affects integrated glucose control, insulin dose requirements, and incidence of hypoglycemia, or contributes to beta-cell failure or to long-term complications of diabetes. Studies in which pregnant women with diabetes were monitored for glycemic control argue against a connection between IAs and fetal risk. Although studies have shown increased levels of immune complexes in patients with diabetic microangiopathic complications, these immune complexes often do not contain insulin or IAs, and insulin administration does not contribute to their formation. The majority of studies have shown no relationship between IAs and diabetic angiopathic complications, including nephropathy, retinopathy, and neuropathy. With the advent of novel insulin formulations and delivery systems, such as insulin pumps and inhaled insulin, examination of these issues is increasingly relevant.
Collapse
Affiliation(s)
- S Edwin Fineberg
- Indiana University School of Medicine, Indianapolis, Indiana 46202, USA.
| | | | | | | | | | | |
Collapse
|
9
|
Valdez SN, Iacono RF, Villalba A, Cardoso Landaburu A, Ermácora MR, Poskus E. A radioligand-binding assay for detecting antibodies specific for proinsulin and insulin using 35S-proinsulin. J Immunol Methods 2003; 279:173-81. [PMID: 12969558 DOI: 10.1016/s0022-1759(03)00197-2] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
A new radioligand-binding assay (RBA) is described for the detection of insulin/proinsulin-specific antibodies using 35S-labeled proinsulin produced by a cell-free reticulocyte extract. Direct use of the crude expression product in the RBA was not feasible because the protein failed to fold properly (or had incorrectly paired disulphide bridges) and purification was hindered by interfering by-products. A refolding protocol and a chromatographic procedure were devised that readily allowed production of purified and immunochemically competent 35S-labeled proinsulin. The new RBA was compared with the reference test, in which the tracer was standard 125I-insulin. The analysis included sera from 41 diabetic patients and 25 healthy controls. Twenty-six (63.4%) and 29 (70.7%) patients scored positive by RBA using 35S-PI and 125I-insulin, respectively. The methods showed a satisfactory correlation with r(2)=0.77 and a slope not significantly different from unity (m=1.16+/-0.10; 95% confidence interval). Since the nuclide used in the assay is 35S, the procedure is compatible with standard assays for GADA and IA-2A, and thus may permit combined assays for the major early markers of autoimmune diabetes.
Collapse
Affiliation(s)
- Silvina N Valdez
- School of Pharmacy and Biochemistry, University of Buenos Aires, Argentina
| | | | | | | | | | | |
Collapse
|
10
|
Goswami R, Jaleel A, Kochupillai NP. Insulin antibody response to bovine insulin therapy: functional significance among insulin requiring young diabetics in India. Diabetes Res Clin Pract 2000; 49:7-15. [PMID: 10808058 DOI: 10.1016/s0168-8227(00)00130-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The majority of young diabetics in India prefer to use low-cost bovine insulin for economic reasons. Therefore, the question of insulin antibody response to bovine insulin and its functional significance is still relevant in the Indian context. We assessed insulin antibody response in 52 young diabetics (type 1, n=25, malnutrition modulated form of diabetes, n=19 and fibrocalculous pancreatopathy (FCP) n=8) on bovine insulin therapy (mean duration 3.0+/-2.1 years) using an internationally standardised in-house radioligand assay. The functional significance of insulin antibody was assessed by calculating their affinity constant, maximum binding capacity and total insulin binding power by Scatchard analysis (type 1, n=14, malnutrition modulated form of diabetes, n=11). All the patients treated with bovine insulin showed high titers of insulin antibodies with S.D. score ranging from 5.1 to 42.0. No significant difference was observed in the mean S.D. score of insulin antibodies in the three diabetic groups. The mean daily insulin dose, maximum insulin binding capacity and total insulin binding power were significantly higher in type 1 when compared to the malnutrition modulated form of diabetes (36+/-8 vs. 26+/-11 IU/day, P<0.05; 9. 7+/-7.8 vs. 4.0+/-3.9 nmol/l, P=0.03 and 59+/-29 vs. 29+/-43, P=0.01, respectively). Insulin antibodies S.D. score and its affinity did not show significant relationship with daily insulin dose and glycemic control (HbAl) at admission. Only 24+/-7% variations in daily insulin requirement were accounted for by total insulin binding power. There was a significant inverse relationship between insulin antibody S.D. score and duration of insulin therapy (r=-0. 4172, P<0.0004). To conclude, insulin antibody response following bovine insulin therapy is not different among type 1, malnutrition modulated form of diabetes and FCP diabetes. The insulin antibody response to bovine insulin therapy does not contribute significantly to increase in daily insulin requirement in bovine insulin treated insulin requiring young diabetics.
Collapse
Affiliation(s)
- R Goswami
- Department of Endocrinology and Metabolism, All India Institute of Medical Sciences, New Delhi, India
| | | | | |
Collapse
|
11
|
Abstract
Argentina has a longstanding tradition of diabetes research, beginning with the seminal work of Prof. Bernardo A. Houssay, who was awarded the first Nobel Prize in Medical Sciences for his studies on the relationship between diabetes and pituitary function. Prof. Luis F. Leloir, who was also awarded the Nobel Prize for his work in carbohydrate metabolism, also inspired younger generations of biologists to work in the field of diabetes research. The aim of this paper is to provide a review of the contributions of Argentine researchers during the 1990s. This manuscript includes only reports of Argentine researchers working on diabetes in local laboratories and quoted in Medline. Thus, important contributions not reported in journals included in Medline or produced by Argentine researchers working abroad may have been omitted. The material consists of a brief description of clinical research (epidemiology and costs, metabolic control, associated risk factors, immunological aspects, and other clinical studies) and basic research (animal model with spontaneous diabetes, islet morphology and function in normal and pathological conditions, insulin action, metabolic disorders related to diabetes, and some miscellaneous effects related to drug-induced diabetes). Altogether, a broad idea of the continuous contribution of our national research to the international field of diabetes is provided, as well as a list of Argentine researchers and research centers devoted to the study of diabetes.
Collapse
Affiliation(s)
- J J Gagliardino
- CENEXA - Centro de Endocrinología Experimental y Aplicada (UNLP-CONICET, WHO Collaborating Center), Facultad de Ciencias Médicas, UNLP, La Plata, Argentina
| |
Collapse
|
12
|
Goswami R, Jayasuryan N, Jaleel A, Tandon N, Kochupillai N. Insulin autoantibodies before and after carbimazole therapy in Asian Indian patients with Graves' disease. Diabetes Res Clin Pract 1998; 40:201-6. [PMID: 9716924 DOI: 10.1016/s0168-8227(98)00052-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Carbimazole therapy can induce insulin autoantibodies (IAA) in Japanese Graves' disease patients, a phenomenon possibly linked to their immunogenetic profile. This phenomenon is not observed in Caucasians. We assessed IAA levels in 114 North Indian Graves' disease patients before and after carbimazole therapy (mean duration 6.2 +/- 3.9 months). The functional significance of IAA was assessed in 46 of them by first phase (sum of +1 and +3 min) insulin response to intravenous glucose (IVGTT) and an oral glucose tolerance test (OGTT) undertaken before commencement of the carbimazole therapy. IAA were measured using a radiobinding assay and expressed as the assay precision unit, S.D. scores (S.D.S), over healthy controls. Before treatment 22 of 114 (19.3%) patients were IAA positive (mean +/- S.D., 5.9 +/- 3.2 S.D.S). After carbimazole therapy a further 11 (9.6%) showed positive for IAA (mean +/- S.D., 3.5 +/- 1 S.D.S). Of the 22 patients who were IAA positive before treatment, 12 became negative after carbimazole therapy. The fasting insulin and first phase insulin responses were similar in IAA positive and IAA negative Graves' disease patients (mean +/- S.D., 61.7 +/- 35.9 versus 88.3 +/- 46.6 pmol/l, P = 0.123 and 1127 +/- 696 versus 1033 +/- 430 pmol/l, P = 0.716, respectively). The OGTT results were comparable in the IAA positive and the IAA negative groups. Thus, North Indian Graves' disease patients, who resemble Caucasians in their HLA haplotypes, behave like Japanese in their tendency to become IAA positive with carbimazole therapy. A subset of the patients who were IAA positive before treatment also demonstrated negative IAA (12/22) after carbimazole therapy.
Collapse
Affiliation(s)
- R Goswami
- Department of Endocrinology and Metabolism, All India Institute of Medical Sciences, New Delhi, India
| | | | | | | | | |
Collapse
|
13
|
Papouchado ML, Valdez SN, Ermácora MR, Gañan S, Poskus E. Highly-sensitive and specific enzyme-linked immunosorbent assays for GAD65 autoantibodies using a thioredoxin-GAD65 fusion antigen. J Immunol Methods 1997; 207:169-78. [PMID: 9368643 DOI: 10.1016/s0022-1759(97)00117-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Autoantibodies against glutamic acid decarboxylase (GAD65) are present in the sera of most patients with recently diagnosed insulin-dependent diabetes mellitus (IDDM). These antibodies appear years before the clinical symptoms, and they are considered to be early markers of the disease. To detect GAD65 autoantibodies (GADA), we developed new enzyme-linked immunosorbent assays (ELISA) with a fusion protein thioredoxin-GAD65 (Trx-GAD65) produced in E. coli as the antigen. These assays were compared with the reference radiobinding assay (RBA). Since most GADA are directed against native epitopes, and adsorption of GAD65 to plastic may cause disruption of its native conformation, the new assays rely on the following immobilization procedures: (a) capture ELISA (c-ELISA) with Trx-GAD65 (protocol A) or biotin-Trx-GAD (protocol B) indirectly immobilized by a non-adsorptive process; (b) ELISA with antigen-antibody preincubation in solution (p-ELISA) in which GADA were reacted first with Trx-GAD65 (protocol C) or biotin-Trx-GAD (protocol D) and the free antigen was determined by conventional ELISA. The results obtained with 42 newly diagnosed IDDM patients and 30 normal individuals were as follows: RBA had 79% sensitivity (percentage of IDDM patients detected) and 97% specificity (100% minus the percentage of false positives). c-ELISA showed low sensitivity (36 and 50%, respectively for protocols A and B), and high specificity (100 and 97%, respectively). p-ELISA were highly-sensitive (74 and 79%, respectively) and specific (97 and 93% for protocols C and D, respectively). Thus, protocols C and D had a performance similar to the reference method. The results reported here provide the basis for simple, highly-sensitive, specific, and widely-applicable tests for GADA that eliminate many of the drawbacks of the radioactive methods.
Collapse
Affiliation(s)
- M L Papouchado
- Cátedra de Inmunología, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Argentina
| | | | | | | | | |
Collapse
|
14
|
Kippen AD, Cerini F, Vadas L, Stöcklin R, Vu L, Offord RE, Rose K. Development of an isotope dilution assay for precise determination of insulin, C-peptide, and proinsulin levels in non-diabetic and type II diabetic individuals with comparison to immunoassay. J Biol Chem 1997; 272:12513-22. [PMID: 9139702 DOI: 10.1074/jbc.272.19.12513] [Citation(s) in RCA: 121] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
We describe the application of a stable isotope dilution assay (IDA) to determine precise insulin, C-peptide, and proinsulin levels in blood by extraction from serum and quantitation by mass spectrometry using analogues of each target protein labeled with stable isotopes. Insulin and C-peptide levels were also determined by immunoassay, which gave consistently higher results than by IDA, the relative difference being larger at low concentrations. Insulin, C-peptide, and proinsulin levels were all shown by IDA to be higher in type II diabetics than in non-diabetics, with mean values rising from 22 (+/- 2) to 92 (+/- 8), 335 (+/- 11) to 821 (+/- 24), and 6 (+/- 1) to 37 (+/- 3) pM, respectively. Interestingly, the ratio between IDA and immunoassay values for insulin levels increased from 1.3 in non-diabetics to 1.7 in type II diabetics. The ratio between proinsulin and insulin levels by IDA increased from 0.24 in non-diabetics to 0.36 in type II diabetics, whereas the ratio between C-peptide and insulin levels by IDA decreased from 17.6 to 10.7. This disproportionate change in protein levels between different types of individuals has implications for the metabolism of insulin in the diabetics studied (type II) and suggests that C-peptide levels are not always a reliable guide as to pancreatic insulin secretion. In addition, levels of the 33-residue C-peptide (partially trimmed form) were shown to be less than 10% that of the fully trimmed 31-residue C-peptide levels, and we tested IDA in a clinical context by two post-pancreatic graft studies. IDA was shown to give direct, positive identification of the target protein with unrivaled accuracy, avoiding many of the problems associated with present methodology for protein determination.
Collapse
Affiliation(s)
- A D Kippen
- Department of Medical Biochemistry, University Medical Centre, Switzerland
| | | | | | | | | | | | | |
Collapse
|