Generates Live Attenuated Norovirus Vaccines for Robust, Long-Term Protection
This in vitro B cell culture system utilizes noroviruses to develop vaccines, providing treatments for murine and human noroviruses. Noroviruses are the most common causes of viral gastroenteritis in humans, and they are highly contagious and indiscriminant. Annually, noroviruses cause 19-21 million cases of illness, 56,000-71,000 hospitalizations, and 570-800 deaths in the United States, as well as a further estimated 200,000 deaths in young children worldwide. No specific medicine to treat norovirus infections exists, nor does a licensed vaccine to prevent norovirus infections. Existing research is limited due to a lack of an in vitro cell culture system, leading to a focus on virus-like particles; however, virus-like particles are non-replicating, may not offer long-term immunity, and are not cost effective to produce. University of Florida researchers have developed an in vitro B cell culture system for murine and human noroviruses. The system has the potential to generate live attenuated norovirus vaccines by propagating and passaging noroviruses in B cells. Nearly all available licensed viral vaccines are generated in this way because live viruses generally provide superior immunity compared to non-replicating antigens. Human norovirus vaccines created with this cell culture system are thus likely to result in robust and long-term protective immunity. The production of these attenuated norovirus vaccines will be much less expensive than the production and purification of VLPs. Further, propagating noroviruses in vitro presents an opportunity to improve upon existing diagnostic tools and antiviral therapeutics.
Live attenuated norovirus vaccines, diagnostic tools, and antiviral therapeutics developed from an in vitro B cell culture system
- Potential to generate live attenuated norovirus vaccines, producing vaccines with improved chances of long-term and robust protection than current non-replicating VLPs
- Propagates noroviruses in vitro, providing a more cost-effective vaccine platform than virus-like particles
- Provides an opportunity to study in vitro norovirus replication, facilitating the development of superior diagnostic tools and antiviral therapeutics
This B cell culture system provides a means to propagate human noroviruses and to generate live attenuated norovirus vaccines, which could offer robust immunity and be cost effective. University of Florida research demonstrates that noroviruses infect B cells, but this infection is unexpectedly non-lethal to the B cell. Infection of cells with nonenveloped viruses such as noroviruses typically causes the infected cell to lyse in order for viral particles to be released, but noroviruses instead persistently infect B cells without killing them. An important application of the cell culture system is the development of norovirus vaccines resulting from the generation of live attenuated noroviruses. The observation that B cells support persistent norovirus infection should facilitate large-scale culturing of viral vaccine candidates. Live attenuated noroviruses are likely to induce better protective immunity than non-replicating virus-like particles being tested as vaccine candidates. The cell culture system also can provide improved diagnostics through its propagation system, which allows for virus amplification and easier viral detection. In addition, it will be instrumental in testing putative antiviral compounds.