Abstract

Hepatitis delta virus (HDV) causes the most severe form of human viral hepatitis. HDV requires a hepatitis B virus (HBV) co-infection to provide HDV with HBV surface antigen envelope proteins. The net effect of HDV is to make the underlying HBV disease worse, including higher rates of hepatocellular carcinoma (HCC). Accurate assessments of current HDV prevalence have been hampered by the lack of readily available and reliable quantitative assays, combined with the absence of an FDA-approved therapy. We sought to develop a convenient assay for accurately screening populations and to use this assay to determine HDV prevalence in a population with abnormally high rates of HCC. We developed a high throughput quantitative microarray antibody capture (Q-MAC) assay for anti-HDV IgG wherein recombinant HDV delta antigen is printed by microarray on slides coated with a noncontinuous, nanostructured plasmonic gold film, enabling quantitative fluorescent detection of anti-HDV antibody in small aliquots of patient serum. This assay was then used to screen all HBV-infected patients identified in a large randomly selected cohort designed to represent the Mongolian population. We identified two quantitative thresholds of captured antibody that were 100% predictive of the sample either being positive on standard western blot, or harboring HDV RNA detectable by qPCR, respectively. Subsequent screening of the HBV-positive cohort revealed that a remarkable 57% were RNA positive and an additional 4% were positive on western blot alone.The Q-MAC assay's unique performance characteristics make it ideal for population screening. Its application to the Mongolian HBsAg+ population reveals an apparent ~60% prevalence of HDV co-infection amongst these HBV-infected Mongolian subjects, which may help explain the extraordinarily high rate of HCC in Mongolia. This article is protected by copyright. All rights reserved.

View details for DOI 10.1002/hep.28957

View details for PubMedID 27880976