Grant: Operating Grant: Industry-partnered Collaborative Research - Other Partner

Respiratory virus infections continue to be significant threats to human health. Although vaccines have successfully eliminated or controlled some of these infections, standard vaccine approaches have failed for others (eg: respiratory syncytial virus, parainfluenza viruses). Furthermore, many of the currently available vaccines have important limitations (eg: growth in eggs, instability, adverse effects, cost). Using molecular biology, some plants can be 'tricked' into making small particles that look like viruses in many ways; so-called virus-like particles (VLP). VLPs have great potential as vaccines for a range of viral diseases because, in some respects, the immune system reacts to them as though they were real viruses. Such VLP-based vaccines have particular promise for respiratory virus infections because they cost little to produce, are non-living and quite stable. IN some instances, they can be administered via the nose. In collaboration with Medicago Inc (Ste-Foy,QC), we have recently demonstrated that plant-derived VLP vaccines for pandemic-strain influenza viruses can be protective in mouse and ferret models. In fact, these vaccine candidates generate surprisingly strong immune responses. Despite their promise, very little is actually known about how these vaccines interact with the immune system (ie: why they work so well). The program of research that we propose focuses on improving our understanding the basic mechanism of action of plant-derived VLP vaccines in animal models and humans using respiratory virus infections as the targeted conditions (eg: influenza, measles). Specifically, we will 1) expose immune cells from animals mice and humans to plant-derived VLP vaccines to study the immune responses generated in detail and 2) use fluorescent plant-derived VLPs to study how these vaccines interact with immune cells and move through immune tissues in animal models.