title: Development of a protocol for the quantitative determination of HBeAg using the Elecsys® HBeAg immunoassay.
abstract: Loss of hepatitis 'e' antigen (HBeAg) in patients with HBeAg-positive chronic hepatitis B is associated with improved long-term clinical outcome and is defined as a goal of antiviral treatment by clinical practice guidelines. Recent studies suggest that baseline levels and on-treatment monitoring of HBeAg levels may identify patients most likely to respond to therapy. The aim of this study was the development of a protocol for the quantitative determination of HBeAg using the Elecsys® HBeAg immunoassay. The linear range of the Elecsys® HBeAg immunoassay was established using recombinant HBeAg and five different diluents. The assay was validated against the Paul Ehrlich Institute (PEI) international standard serum. Linearity was demonstrated up to a cut-off index (COI) of 1000, independent of the diluent used. Optimal linearity was obtained using the Elecsys® Universal Diluent. Using the PEI reference standard, conversion factors were established as 4.50 COI for 1 PEIU/mL corresponding to 0.222 PEIU/mL for a COI of 1. Based on the results from these analyses, a simple algorithm for the quantitative measurement of HBeAg using the Elecsys® HBeAg immunoassay was developed. Using a simple algorithm with an initial 1:40 dilution, the Elecsys® HBeAg assay provides robust quantification of serum HBeAg in an easy-to-use and rapid system. The use of a commercially available, standardized diluent improves comparability between laboratories.
authors.affiliation: Department of Gastroenterology, Hepatology and Endocrinology, Hannover Medical School, Hannover, Germany. karsten@mh-hannover.de
authors.forename: K
authors.initials: K
authors.lastname: Wursthorn
authors.forename: B J
authors.initials: BJ
authors.lastname: Zacher
authors.forename: J
authors.initials: J
authors.lastname: Jaroszewicz
authors.forename: M
authors.initials: M
authors.lastname: Darnedde
authors.forename: M
authors.initials: M
authors.lastname: Manns
authors.forename: H
authors.initials: H
authors.lastname: Wedemeyer
mesh_terms: D000465:Algorithms; D006513:Hepatitis B e Antigens / Q000032:analysis / Q000097:blood* / Q000276:immunology; D019694:Hepatitis B, Chronic / Q000175:diagnosis / Q000276:immunology; D006801:Humans; D007118:Immunoassay / Q000379:methods*; D012015:Reference Standards
chemical_list: D006513:Hepatitis B e Antigens