Development of a contemporary globally diverse HIV viral panel by the EQAPOL program

The significant diversity among HIV-1 variants poses serious challenges for vaccine development and for developing sensitive assays for screening, surveillance, diagnosis, and clinical management. Recognizing a need to develop a panel of HIV representing the current genetic and geographic diversity NIH/NIAID contracted the External Quality Assurance Program Oversight Laboratory (EQAPOL) to isolate, characterize and establish panels of HIV-1 strains representing global diverse subtypes and circulating recombinant forms (CRFs), and to make them available to the research community. HIV-positive plasma specimens and previously established isolates were collected through a variety of collaborations with a preference for samples from acutely/recently infected persons. Source specimens were cultured to high-titer/high-volume using well-characterized cryopreserved PBMCs from National y donors. Panel samples were stored as neat culture supernatant or diluted into defibrinated plasma. Characterization for the final expanded virus stocks included viral load, p24 antigen, infectivity (TCID), sterility, coreceptor usage, and near full-length genome sequencing. Viruses are made available to approved, interested laboratories using an online ordering application. The current EQAPOL Viral Diversity panel includes 100 viral specimens representing 6 subtypes (A, B, C, D, F, and G), 2 sub-subtypes (F1 and F2), 7 CRFs (01, 02, 04, 14, 22, 24, and 47), 19 URFs and 3 group O viruses from 22 countries. The EQAPOL Viral Diversity panel is an invaluable collection of well-characterized reagents that are available to the scientific community, including researchers, epidemiologists, and commercial manufacturers of diagnostics and pharmaceuticals to support HIV research, as well as diagnostic and vaccine development.