Solid-Phase enzyme immunoassay for terminal deoxynucleotidyl transferase (abbott tdt-eia) in extracts of whole blood and mononuclear cells isolated from bone marrow and blood

✍ Scribed by Tod R. Fairbanks; William J. King; Mary Sue Coleman; Paul R. Finley; Herbert A. Fritsche; John J. Hutter; John F. O'Brien; George L. Manderino

• Publisher: John Wiley and Sons
• Year: 1987
• Tongue: English
• Weight: 874 KB
• Volume: 1
• Category: Article
• ISSN: 0887-8013
• DOI: 10.1002/jcla.1860010206

✦ Synopsis

The Abbott enzyme immunoassay for detecting terminal transferase (TdT-EIA) was evaluated at four institutions. Extracts of mononuclear cells isolated from bone marrow and peripheral blood of individuals with leukemic and nonleukemic diseases were assayed. In addition, whole blood specimens, in which TdT was extracted from mononuclear cells directly in blood, were assayed. Intrarun, interrun, and between laboratory coefficients of variation ranged from 6.2%-9.3%, 9.4%-11.1%, and 10.9-13.5%, respectively. Since TdT quantitation in whole blood extracts might be adversely affected by blood components and exogenous substances, studies were carried out to determine whether the TdT-EIA accurately measured TdT in blood. TdT recovery was virtually 100% in blood ex-tracts provided that an extraction buffer, included in the TdT-EIA kit, was used. Addition of lipids, human gamma globulin, bilirubin, bacterial DNA polymerase, and chemotherapeutic drugs commonly used to treat acute lymphocytic leukemia had no effect on TdT antigenic activity in whole blood specimens. Linear regression analysis at two institutions comparing TdT quantitation using the TdT-EIA and DNA polymerase assays yielded correlation coefficients of 0.88 and 0.92. Assay results from 1,019 clinical specimens were used to establish expected values for extracts of whole blood and isolated mononuclear cells from blood and bone marrow. The data demonstrate that the TdT-EIA is a reproducible assay for quantitating TdT levels in clinical specimens.