DELISA: sensitive nonisotopic assay for GAD65 autoantibodies, a key risk-assessment marker for insulin-dependent diabetes mellitus
Autor: | B S Vold, Edwin F. Ullman, S Minkin, H B Mehta |
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Rok vydání: | 1996 |
Předmět: |
chemistry.chemical_classification
medicine.medical_specialty endocrine system diseases biology Biochemistry (medical) Clinical Biochemistry Glutamate decarboxylase Autoantibody Molecular biology Serology Endocrinology Enzyme Antigen chemistry Internal medicine Biotinylation medicine biology.protein Antibody Conjugate |
Zdroj: | Clinical Chemistry. 42:263-269 |
ISSN: | 1530-8561 0009-9147 |
DOI: | 10.1093/clinchem/42.2.263 |
Popis: | Nonisotopic assays for the measurement of autoantibodies to 65-kDa glutamic acid decarboxylase (GAD65) have not previously achieved performance equivalent to radiobinding assays (RBA). We have developed a modified ELISA protocol, DELISA, for measuring autoantibodies to GAD65 in serum. The method overcomes the problems of poor sensitivity and specificity associated with conventional ELISAs. Serum containing GAD65 autoantibodies is incubated with biotinylated GAD65 (bGAD65). Sufficient soluble Protein A-dextran conjugate is added to bind the immunoglobulins in the sample, including GAD65 autoantibodies to which GAD65 is bound. After incubation, the mixture is transferred to a streptavidin-p4ated microtiter well, which binds free bGAD65 but not bGAD65 bound to autoantibodies. Streptavidin-bound bGAD65 is detected by means of a peroxidase-GAS65MAb conjugate. The method appears to have comparable sensitivity and specificity to those of RBAs. Reaction of the antibodies with soluble antigen to increase the binding rate and the use of high serum concentrations and very low antigen concentrations to increase sensitivity are critical elements of the method. |
Databáze: | OpenAIRE |
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