Description:
Background: The estimation of HIV incidence, or the rate of new infections in a population, is an important public health indicator that provides valuable information on the growth of the epidemic and the efficacy of various intervention strategies. Within the past 15 years, a new strategy for estimating HIV incidence has been employed based on the observation that certain biomarkers (mainly HIV-specific antibody levels and avidity) can distinguish recent from long-term infection. Since the immune response to HIV gradually develops post-infection, the immune profile of newly infected individuals will present differently from the immune profile of individuals with chronic infection. Although several laboratory tests have been developed for the purpose of identifying recent infection, most approaches rely on a single assay measure. Relying on a single measure of the immune response is subject to greater misclassification due to inherent immune variation among individuals. Recent studies have shown that a combination of antibody responses or immune measures may reduce misclassification rates and improve incidence estimates. Ideally, multiple immune responses should be measured in a single assay, since it is not always feasible or cost effective to require several different tests for accurate incidence estimates.
Project Goal: The goal of the proposed project is to develop a portable and cost-effective assay that is capable of measuring multiple immune responses at the same time (multiplexing). The assay should be able to provide a quantitative or semi-quantitative measure of HIV-specific antibody levels and avidity to multiple antigens using a relatively small volume of plasma (≤ 20μl). The assay should be similar in sensitivity to HIV antibody-based tests that are currently commercially available. While several technologies with multiplexing capability do exist, there are some limitations to the assay formats, as they are typically costly, technically complicated, and not accessible to all testing settings/ laboratories. The technology should be a portable, high-throughput, and a scalable multiplexing platform for determining recent infection.
Impact: The availability of a low-cost, portable assay that can measure multiple HIV-specific biomarkers will enhance accessibility to diverse laboratory or field settings, enabling large-scale use of HIV incidence by various public health entities to chart their respective epidemics. The platform may also be suitable for other infectious disease diagnostics.
