Dynamics of the HIV Virological Synapse

Drexel University, Philadelphia PA

Investigators

Abstract

This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5) 0853680 Papazoglou The overall goal of this research is to elucidate the dynamics of the molecular interactions that occur between an HIV viral particle and a host cell, and to explore methods to change and control the steps that lead to virus-cell fusion. The HIV-1 life cycle that leads to cell infection and AIDS is triggered by a sequence of interaction steps and conformational re-arrangements between proteins at the virus-cell interface, the virological synapse. The underlying hypothesis is that the coordinated dynamics of receptor assembly and envelope conformational changes at the synapse can be perturbed by engineered and targeted nanoparticle constructs. Understanding how nanomaterials affect the molecular events at the virus-cell interface can lead to methods to interfere with cell and tissue infection by altering the timing of envelope-receptor transitions. The proposed research has the followings specific steps: a) create fluorescent constructs to track receptor diffusion and assembly, b) trigger assembly of receptors by virus-like particles, and c) use nanomaterials, as well as envelope protein inhibitors, to control the rate of movement of receptors and viral spike proteins. This research embodies several components of high impact innovation. 1) Combined use of virus-like particles and recombinant cells expressing fluorescent host cell receptors will enable an experimental bridge between molecular events of HIV entry and downstream infectivity. 2) The dynamics of both receptor diffusion and assembly as well as the rearrangement steps of viral envelope proteins will be quantified. This will enable an assessment of how controlling dynamics of protein assembly and re-arrangement at the virological synapse can control infection. 3) Gold nanoparticles will be used to determine coordination of the time-dependence of assembly and conformational reorganization in the HIV-1 virological synapse and whether modulation of these time-dependent events can ultimately be utilized for disease intervention. The ability of the research team to combine expertise in recombinant cells, virus-like particles and nanomaterials will allow them to follow and quantify the dynamics of both receptor diffusion and assembly events, and test the impact on infectivity of nanomaterial and inhibitor constructs. The results of this research will generate valuable new knowledge on the mechanism of viral fusion machines and promote new thinking for the design of molecular entities that could retard or totally abort HIV-1 infection. The potential benefit of creating more effective inhibitors by fusing gold nanoparticles with envelope-binding molecular inhibitors will be explored. At the training and education levels, lab modules to enrich bio/nanotechnology training will be developed and used as portable modules in other Departments / Universities. Enrichment of 7-12th grade education with exciting research examples from the HIV-AIDS field will allow bridging the gap between rigidly identified educational levels and students interested in scientific career paths. HIV/AIDS is a globally impactful and relevant topic that is critical to teach to upper middle school and high school students. The concept of viral spikes attacking cells using fusion machines is one that exemplifies nanomachines and biomimetic concepts. Methods to target the viral spikes and how they can lead to different treatment types (drugs, vaccines, microbiocides) will teach students the connections between fundamental knowledge and biomedical applications.