1263701(Daniel). Technical part: The overall goal of the proposed research is to develop a single particle experimental platform for the identification and characterization of enveloped viruses based on their entry kinetics. This platform will integrate two key technologies: 1) single particle imaging of virus binding and viral-host membrane fusion of individual virion particles to a supported bilayer platform, and 2) statistical analysis of these individual events to discriminate populations based on variations in entry kinetic parameters. In this project, virus will serve as a model virus because it is one of the most studied viruses and thus the entry mechanism is well understood; its surface proteins are easily mutated and adapted to different cell types; it is well known that binding and fusion can vary among viral strains, e.g. H5 (avian) versus H3 (human) strains, and that these variations are correlated to infectivity. We propose that the rapid characterization of entry kinetics of virus samples from an infected person, made possible by the methods we employ here, can be used to determine which phenotypes the person (or a tissue sample) is infected with. In the case of influenza, this kind of rapid detection may be critical to promptly tracking the spread of virus during a pandemic outbreak or intentional release. In influenza, viral entry processes are controlled by the same protein, hemagglutinin (HA), which complicates decoupling binding from fusion in the overall entry kinetics. With current technology, it is only possible to assess separately, but not within the same virion, binding and fusion kinetics. This proposed platform discriminates between these processes within an individual virion, providing quantitative kinetic information on both processes that can then be used to identify phenotypes. Phenotype detection without PCR is currently a grand challenge in virus detection. Thus this is a potentially transformative technology that will aid in quickly discriminating among virus phenotypes in a mixed sample.
Non-technical part: This proposal will develop better understanding of how influenza virus subtypes enter the cell during infection. This understanding is important and authors postulate that it may be used to discriminate more harmful from less harmful types of infleunza. This project will therefore have significant societal benefit down the road by helping develop better influenaza diagnostic tools.
