Development of an international external quality assurance program for HIV-1 incidence using the Limiting Antigen Avidity assay.


Laboratory assays for identifying recent HIV-1 infections are widely used for estimating incidence in cross-sectional population-level surveys in global HIV-1surveillance. Adequate assay and laboratory performance are required to ensure accurate incidence estimates. The NIAID-supported External Quality Assurance Program Oversight Laboratory (EQAPOL) established a proficiency testing program for the most widely-used incidence assay, the HIV-1 Limiting Antigen Avidity EIA (LAg), with US Centers for Disease Control and Prevention (CDC)-approved kits manufactured by Sedia Biosciences Corporation and Maxim Biomedical. The objective of this program is to monitor the performance of participating laboratories. Four rounds of blinded external proficiency (EP) panels were distributed to up to twenty testing sites (7 North American, 5 African, 4 Asian, 2 South American and 2 European). These panels consisted of ten plasma samples: three blinded well-characterized HIV-1-seropositive samples that were included as replicates and an HIV-negative control. The seropositive samples spanned the dynamic range of the assay and are categorized as either recent or long-term infection. Participating sites performed the assay according to manufacturers' instructions and completed an online survey to gather information on kit manufacturer, lot of kit used, laboratory procedures and the experience of technicians. On average, fifteen sites participated in each round of testing, with an average of four sites testing with only the Maxim assay, seven testing with only the Sedia assay and five sites utilizing both assays. Overall, the Sedia and Maxim assays yielded similar infection status categorization across the laboratories; however, for most of the nine HIV+ samples tested, there were significant differences in the optical density readouts, ODn (N = 8) and OD (N = 7), between LAg kit manufacturers (p < 0.05 based on mixed effects models. The EQAPOL LAg program is important for monitoring laboratory performance as well as detecting variations between manufacturers of HIV-1incidence assays.





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Publication Info

Keating, Sheila M, Wes Rountree, Eduard Grebe, Andrea L Pappas, Mars Stone, Dylan Hampton, Christopher A Todd, Marek S Poniewierski, et al. (2019). Development of an international external quality assurance program for HIV-1 incidence using the Limiting Antigen Avidity assay. PloS one, 14(9). p. e0222290. 10.1371/journal.pone.0222290 Retrieved from

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Thomas Norton Denny

Professor in Medicine

Thomas N. Denny, MSc, M.Phil, is the Chief Operating Officer of the Duke Human Vaccine Institute (DHVI), Associate Dean for Duke Research and Discovery @RTP, and a Professor of Medicine in the Department of Medicine at Duke University Medical Center. He is also an Affiliate Member of the Duke Global Health Institute. Previously, he served on the Health Sector Advisory Council of the Duke University Fuquay School of Business. Prior to joining Duke, he was an Associate Professor of Pathology, Laboratory Medicine and Pediatrics, Associate Professor of Preventive Medicine and Community Health and Assistant Dean for Research in Health Policy at the New Jersey Medical School, Newark, New Jersey. He has served on numerous committees for the NIH over the last two decades and currently is the principal investigator of an NIH portfolio in excess of 65 million dollars. Mr. Denny was a 2002-2003 Robert Wood Johnson Foundation Health Policy Fellow at the Institute of Medicine of the National Academies (IOM). As a fellow, he served on the US Senate Health, Education, Labor and Pensions Committee with legislation/policy responsibilities in global AIDS, bioterrorism, clinical trials/human subject protection and vaccine related-issues.

As the Chief Operating Officer of the DHVI, Mr. Denny has senior oversight of the DHVI research portfolio and the units/teams that support the DHVI mission. He has extensive international experience and previously was a consultant to the U.S. Centers for Disease Control and Prevention (CDC) for the President’s Emergency Plan for AIDS Relief (PEPFAR) project to oversee the development of an HIV and Public Health Center of Excellence laboratory network in Guyana. In September 2004, the IOM appointed him as a consultant to their Board on Global Health Committee studying the options for overseas placement of U.S. health professionals and the development of an assessment plan for activities related to the 2003 PEPFAR legislative act. In the 1980s, Mr. Denny helped establish a small laboratory in the Republic of Kalmykia (former Soviet Union) to improve the care of children with HIV/AIDS and served as a Board Member of the Children of Chernobyl Relief Fund Foundation. In 2005, Mr. Denny was named a consulting medical/scientific officer to the WHO Global AIDS Program in Geneva. He has also served as program reviewers for the governments of the Netherlands and South Africa as well as an advisor to several U.S. biotech companies. He currently serves as the Chair of the Scientific Advisory Board for Grid Biosciences.

Mr. Denny has authored and co-authored more than 200 peer-reviewed papers and serves on the editorial board of Communications in Cytometry and Journal of Clinical Virology. He holds an M.Sc in Molecular and Biomedical Immunology from the University of East London and a degree in Medical Law (M.Phil) from the Institute of Law and Ethics in Medicine, School of Law, University of Glasgow. In 1991, he completed a course of study in Strategic Management at The Wharton School, University of Pennsylvania. In 1993, he completed the Program for Advanced Training in Biomedical Research Management at Harvard School of Public Health. In December 2005, he was inducted as a Fellow into the College of Physicians of Philadelphia, the oldest medical society in the US.

While living in New Jersey, Mr. Denny was active in his community, gaining additional experience from two publicly elected positions. In 2000, Mr. Denny was selected by the New Jersey League of Municipalities to Chair the New Jersey Community Mental Health Citizens’ Advisory Board and Mental Health Planning Council as a gubernatorial appointment.

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