Scientists from The University of Texas at Austin, alongside colleagues from the University of North Carolina at Chapel Hill and the National Institutes of Health, have made significant progress in combating norovirus. Their study, published in Science Translational Medicine, reveals antibodies that can neutralize various strains of norovirus. This discovery may lead to a broadly effective vaccine and new treatments for gastroenteritis caused by the virus.
Norovirus affects over 700 million people annually, leading to severe symptoms like diarrhea and vomiting. While most recover, it poses a risk to vulnerable groups such as young children and older adults. Vaccine development has been difficult due to the virus's genetic diversity and mutation rate.
The research team used advanced molecular analysis on participants who received an experimental oral vaccine by Vaxart. They found some individuals produced antibodies capable of neutralizing multiple norovirus strains, including historical and emerging variants responsible for about 75% of global outbreaks.
“These findings provide critical insights into how the immune system responds to norovirus and pave the way for designing a vaccine that offers broad, long-lasting protection,” said George Georgiou, co-corresponding author and professor at UT. “We found antibodies that are very broad in terms of being able to neutralize many different variants that have circulated or are circulating now.”
One antibody identified, VX22, targets a previously unknown weak spot in the virus's structure. Unlike typical antibodies that attack only one or two strains, VX22 can neutralize multiple genotypes by binding to a conserved region in the virus particles.
“Norovirus cases this winter have surged to twice the two previous annual peaks," noted Juyeon Park, first author and postdoctoral researcher at UT. "Our findings can better inform the future design of vaccine development against norovirus.”
Norovirus spreads easily through contaminated sources like food and water, often causing outbreaks in crowded settings such as schools and cruise ships. A comprehensive vaccine could significantly reduce infections and hospitalizations.
The newly identified antibodies might also aid in developing therapies for those with compromised immune systems who struggle with infection independently.
“This discovery brings us closer to a vaccine that could provide lasting protection," Georgiou added.
The research team is refining their vaccine design while testing its effectiveness across broader populations like elderly individuals and children.
Authors involved include Ed Satterwhite et al., from UT; Lisa C. Lindesmith et al., from UNC; Adam S. Olia et al., from NIH's Vaccine Research Center; Veronica P. Costantini et al., from CDC; Cynthia E. Kelley et al., from Utrecht University; Yaroslav Tsybovsky et al., from Frederick National Laboratory for Cancer Research; Becca Flitter et al., from Vaxart.
Funding came from several organizations including NIH's National Institute of Allergy and Infectious Diseases, Dutch Research Council among others. George Georgiou holds an engineering chair position at UT.
Several authors have filed patent applications related to these broadly neutralizing antibodies discovered during this research.