Virology Core

Johns Hopkins University, Baltimore MD

Investigators

Abstract

The main goals of the Virology Core are to 1) use standardized assays to perform state-of-the art HBV virological testing from participant samples obtained by the Shared Resources Core and to generate high-quality results for use in statistical analyses in all Projects in the Hepatitis B HIV Cure Consortium (BICC); 2) optimize existing and develop novel assays to facilitate success of each Project; and 3) provide support for use of in vitro and in vivo models in experiments performed by all Projects. Chronic Hepatitis B (CHB) remains a global public health problem with ~316 million individuals and ~10% of people with HIV persistently infected globally. Currently, CHB is treated with direct-acting antiviral drugs that suppress viral replication; however, these antiviral drugs are not curative. As such, infected patients are required to remain on treatment indefinitely to prevent viral rebound and reduce the risk of liver disease progression. Functional HBV cure is defined as loss of hepatitis B surface antigen (HBsAg) from blood 24 weeks after treatment cessation. Because current treatment rarely leads to HBsAg loss, BICC focuses on detailed characterization, both virologically and immunologically, of HBsAg dynamics during treatment in PWH and hepatitis B (PWHHB) and a control group of people with hepatitis B (PWHB). BICC includes sites in the United States, Senegal, Uganda, India, and Brazil who will all recruit participants and store biological samples. The Virology Core will be led by Dr. Thio and Co-investigators and will also include investigators from each site. The majority of HBV virological markers will be run at the local sites using the same assays and platform allowing for standardization across the sites. Each of the proposed sites already has equipment in place and has been trained to use these assays, so testing can begin rapidly after recruitment is initiated. The sites will enter data into a REDCap database, which will be used by the Statistical and Data Management Center to produce summary reports and perform analyses. In Aim 1 we will perform the HBV, HIV, and HDV virological testing and HCC markers on each semi-annual visit for all participants and also on stored samples from the longitudinal cohorts MACW/WIHS Combined Cohort Study and the CFAR Network of Integrated Systems who have participants with characteristics of those in BICC. Early-stage investigators and trainees at each site will learn how to perform these assays to enrich the number of young investigators in HBV cure. Aim 2 will develop and apply novel HBV molecular assays to support the Projects. Specifically, we will 1) apply an assay that we have developed to determine production of HBsAg from either the HBV replication template or HBV integrated into host genome, 2) provide sequencing from HBV RNA, and 3) produce a novel HBV reporter virus for neutralizing antibody studies for the Immunology Project. Aim 3 maintains in vitro models of HBV infection for the Projects and characterizes the HIV-HBV rhesus macaque model for potential in vivo hypothesis testing arising from Projects.