Formation of virus-like particles from human cell lines exclusively expressing Influenza neuraminidase

The minimal viral requirements for the generation of influenza virus like particle (VLP) assembly and budding was reassessed. Using neuraminidase from the H5N1 and H1N1 subtypes, it was found that the expression of neuraminidase (NA) alone was sufficient to generate and release VLPs. Biochemical and functional characterization of the NA containing VLPs demonstrated that they were morphologically similar to influenza virions. The NA oligomerization was comparable to that of the live virus, and the enzymatic activity, while not required for the release of NA-VLP, was preserved. Together, these findings indicate that NA plays a key role in virus budding and morphogenesis and demonstrates that NA-VLPs represent a useful tool in influenza research.