Collaborative Study to Establish National Reference Standards for Anti-HIV-1 Antibody

Background: National reference standards for anti-HIV-1 antibody are needed to evaluate the performance and maintain the quality control of anti-HIV-1 antibody assays. The aim of this study was to prepare a mixed-titer performance panel and assess its suitability as a national reference standard for anti-HIV-1 antibody according to stability, collaboration, and other studies.Methods: Nineteen serum samples from different HIV patients were obtained, along with 15 units of fresh frozen plasma samples with negative anti-HIV-1 antibody results. Ten anti -HIV-1 antibody-positive candidate standards and two negative candidate standards were prepared based on the reactivity in the Alinity i HIV Ag/Ab combo assay (Abbott Laborato-ries, Wiesbaden, Germany). A collaborative study was conducted across eight laboratories using five anti-HIV-1 antibody assays. Real-time and accelerated stability were evaluated to assess the long-term stability.Results: In the collaborative study, results of all five anti-HIV-1 antibody assays were posi-tive for all 10 candidate standards prepared using HIV patient samples. The CV of each as-say for every candidate standard was within 10%, except for one assay result. No real-time and accelerated stability change trend was observed at -70 degrees C or -20 degrees C, supporting that the reference standards were maintained in a stable state at -70 degrees C for long-term storage. Conclusions: The overall results suggest that the 12 candidate standards could serve as national reference standards for anti-HIV-1 antibody.