Citation

Thirunavukarasu PP, Wallace EM. Prenatal Diagnosis 2001; 21(8): 638-641.

Copyright

(Copyright © 2001)

DOI

10.1002/pd.127

PMID

11536262

Abstract

Inhibin A is a useful prenatal marker of Down syndrome. Currently, the available enzyme-linked immunosorbent assays (ELISAs) for inhibin A are based upon the same paired monoclonal antibodies. In the present study we have confirmed for one of those ELISAs that short-term sample storage as whole blood leads to a significant decline in detectable inhibin A and that this is most likely due to erythrocyte catalase interference with a critical oxidation step in the assay. While this interference can be eliminated by heating the samples pre-assay, this process is labour intensive. In the present study we have demonstrated that the addition of 3-amino-1,2,4-triazole (AT), a catalase 'suicide' inhibitor, also prevents the decline of inhibin A levels in samples stored as whole blood. We suggest that the addition of AT to samples prior to assay is a simple modification to the inhibin A ELISA that affords optimum performance.

Language: en

Keywords

Amitrole; Down Syndrome; Enzyme Inhibitors; Enzyme-Linked Immunosorbent Assay; Female; Humans; Inhibins; Pregnancy; Pregnancy Trimester, First; Pregnancy Trimester, Second; Prenatal Diagnosis; Specimen Handling