The norovirus is a nasty virus that causes acute gastroenteritis in humans. It is highly contagious and can be contracted from an infected person, contaminated food, and surfaces (CDC). An individual can become infected multiple times within their life and it can be a serious illness in young children and older adults if not treated correctly (CDC). There is currently no vaccine for norovirus, but studies have shown a potential for the development of a vaccine using the P particle of this virus.
Norovirus is a nonenveloped virus that has an outer protein capsid made of two domains. The shell (S) domain forms the interior part of the capsid while the protrusion (P) domain sticks out of the capsid (Tan, Ming, et al., 2011). The P domain forms the P particle that binds to histo-blood group antigen (HBGAs) receptors. This particle has been tested as a potential carrier for vaccine development against norovirus (Tan, Ming, et al., 2011). Studies involving the P particle have also should strong preference for protection against rotavirus as well (Tan, Ming, et al., 2011).
Figure 1. The three loops on the P particle of the P domain.
The P particle is octahedral in structure and contains three loops on the surface of the P domain (Tan, Ming, et al., 2011). These loops pose a major opportunity for developing a vaccine as they can tolerate the insertion of a foreign antigen and can make multiple copies on the three loops for a stronger presence of antigens. The His tag was inserted intothe P particle and administered to mice The Hig tag was inserted into the P particle, cloned in E. coli, and purified before being administered to mice. After infecting the treated mice with norovirus the rate immunity against the
Figure 2. The His tag was inserted into the P domain.
virus was measured. The insertion of the His tag into the P particle, specifically into loop 2, showed to enhance immunity and antibody response in the mice exposed to norovirus (Tan, Ming, et al., 2011). The insertion did not cause any structural changes within the virus as it kept its octahedral shape like its wildtype counterpart, but did not allow for effective binding to the HBGA receptors (Tan, Ming, et al., 2011).
The P particle serves as a strong platform for vaccine development against norovirus. It is easily replicated, structurally stable, and a good subunit for creating a vaccine against norovirus. The multiple loops of its structure provides more opportunities for different vaccine designs as well as its easy cloning property makes it highly efficient and cost effective (Tan, Ming, et al., 2011). Overall, the P particle shows promise for developing a vaccine against the gastrointestinal virus.
References:
Tan, Ming, et al. “Norovirus P particle, a novel platform for vaccine development and antibody production.” Journal of virology 85.2 (2011): 753-764.
“Overview.” Centers for Disease Control and Prevention. Centers for Disease Control and Prevention, 26 July 2013. Web. 13 Apr. 2016. <http://www.cdc.gov/norovirus/about/overview.html>.
Stonehill Virology 2016 
This was very interesting to read about, as I also researched vaccine development, reading about the different methods and ways that the coat can be manipulated is so interesting. I think you did a great job explaining the structure of the virus and how the vaccine could potentially be developed against it! Do you know if there are any current trials or developments in creating this vaccine?
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Glad you found the description on the virus structure and and opportunity for the vaccine development easy to follow! I did just find an article about a trial with adults 18-50 year olds who were treated with a placebo or norovirus viruslike particle vaccine. (http://www.nejm.org/doi/full/10.1056/nejmoa1101245) For the most part a lot of these studies are still dealing with computational analyses and manipulations of different antigens and insertions along with the His tag. I think it’s taking some time since the 3 different loops allow for a variety of possibilities in the development of a potential norovirus vaccine.
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Hi Kim, very interesting information on this virus! In regards to infecting the mice with the virus and measuring their rate immunity, I was wondering if this has been tested in other animals such as primates? Overall, I think it is really beneficial for our society that researchers are looking into developing a vaccine / treatment for this virus that occurs in our every day lives.
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Hi Devin, great question. There actually have been some studies using primates. Rhesus macaques seem to be the most promising animal model to study the immune response against norovirus and ultimately developing a vaccine for humans against norovirus.
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I did the norovirus for my capstone project and I found this article as well. I thought you did a really nice job explaining the study in a way that was easy to understand, and your post actually helped me with my paper. There is an immense need for a norovirus vaccine because it causes nearly 19-21 million illnesses each year, and can affect anyone. It is so interesting to see the different attempts at making a vaccine that researchers try, especially since there are five different genogroups of the virus. It will be interesting to see if the P particle platform is eventually used to make a vaccine that works.
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I agree, the development of an effective vaccine is so important especially since this illness can be spread so easily. The structure of the P particle definitely holds a lot of potential so I think these different attempts could defintely lead to a viable vaccine. I’m glad this post was able to help you with your capstone!
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