Surya N Mulukutla1, Maria Acevedo-Calado1, Christiane S Hampe2, Massimo Pietropaolo3, Ashok Balasubramanyam3. 1. Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, Baylor College of Medicine, Houston, TX. 2. Division of Metabolism, Endocrinology and Nutrition, Department of Medicine, University of Washington, Seattle, WA. 3. Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, Baylor College of Medicine, Houston, TX massimo.pietropaolo@bcm.edu ashokb@bcm.edu.
Abstract
OBJECTIVE: Autoantibodies directed against tyrosine phosphatase IA-2 antibody (IA-2 Ab) are diagnostic for autoimmune type 1 diabetes. Conventional assays target the intracellular domain of IA-2. Among patients with ketosis-prone diabetes (KPD), characterized by presentation with diabetic ketoacidosis (DKA), >60% of adults lack three classic islet autoantibodies-IA-2, GAD65, and ZnT8 Abs-associated with type 1 diabetes. We aimed to determine whether apparently autoantibody-negative ("A-") KPD patients possess occult IA-2 Ab directed against full-length IA-2 (IA-2FL) or its extracellular domain (IA-2EC). RESEARCH DESIGN AND METHODS: We developed an assay that targets IA-2FL and IA-2EC and used it to analyze 288 subjects with A- KPD. RESULTS: Ten A- KPD patients were positive for IA-2EC Ab (3.5%), and three were also positive for IA-2FL Ab (1.0%), similar to frequencies in type 1 and type 2 diabetes. CONCLUSIONS: Measurement of IA-2FL Ab and IA-2EC Ab improves the accuracy of the Aβ classification of KPD patients.
OBJECTIVE: Autoantibodies directed against tyrosine phosphatase IA-2 antibody (IA-2 Ab) are diagnostic for autoimmune type 1 diabetes. Conventional assays target the intracellular domain of IA-2. Among patients with ketosis-prone diabetes (KPD), characterized by presentation with diabetic ketoacidosis (DKA), >60% of adults lack three classic islet autoantibodies-IA-2, GAD65, and ZnT8 Abs-associated with type 1 diabetes. We aimed to determine whether apparently autoantibody-negative ("A-") KPDpatients possess occult IA-2 Ab directed against full-length IA-2 (IA-2FL) or its extracellular domain (IA-2EC). RESEARCH DESIGN AND METHODS: We developed an assay that targets IA-2FL and IA-2EC and used it to analyze 288 subjects with A- KPD. RESULTS: Ten A- KPDpatients were positive for IA-2EC Ab (3.5%), and three were also positive for IA-2FL Ab (1.0%), similar to frequencies in type 1 and type 2 diabetes. CONCLUSIONS: Measurement of IA-2FL Ab and IA-2EC Ab improves the accuracy of the Aβ classification of KPDpatients.
Authors: Michael P Morran; Anna Casu; Vincent C Arena; Susan Pietropaolo; Ying-Jian Zhang; Leslie S Satin; Patrick Nelson; Gilbert S Omenn; Massimo Trucco; Dorothy J Becker; Massimo Pietropaolo Journal: Endocrinology Date: 2010-04-09 Impact factor: 4.736
Authors: Maria Acevedo-Calado; Eddie A James; Michael P Morran; Susan L Pietropaolo; Qin Ouyang; David Arribas-Layton; Marco Songini; Marco Liguori; Anna Casu; Richard J Auchus; Shuai Huang; Liping Yu; Aaron Michels; Roberto Gianani; Massimo Pietropaolo Journal: Diabetes Care Date: 2017-02-07 Impact factor: 19.112