ZBiotech’s N-glycan microarray helps scientists decipher receptor binding profiles of influenza viruses.

The current dominant platform for producing influenza vaccines is based on using chicken eggs. With many disadvantages of egg-based vaccine production, influenza vaccine production is shifting to mammalian cell culture–based platforms in which, however, the virus yields are much lower. Wen and colleagues aimed to improve the yields and thermostability of influenza A virus production in a culture-based platform by randomly introducing mutations into hemagglutinin. One mutation of hemagglutinin, Y161F, increased the infectivity and thermostability of the produced virus. Therefore, the Y161F mutant could be used to optimize influenza A vaccine production.

To fully characterize the glycan binding profile of the Y161F mutant, its binding properties were tested and compared to the wild type (WT) using our N-glycan microarray containing 114 synthesized N-glycans. The researchers found that both Y161F and WT predominantly bind to N-glycans terminating with N-acetylneuraminic acid (Neu5Ac). Wild-type influenza virus showed stronger binding to α2,6-Neu5Ac-linked glycans, whereas the Y161F mutant was preferably bound to α2,3-Neu5Ac-linked glycans, and a lesser extent, to the α2,6-Neu5Ac-linked glycans. When the Neu5Ac group was removed, no binding of viruses was observed. The Y161F mutant also had increased binding affinities towards glycan analogs 3′-sialyl-N-acetyllactosamine and 6′-sialyl-N-acetyllactosamine compared to the wild type.

Our N-glycan microarrays are a useful tool that scientists can use to characterize the binding profile of viral proteins and viral particles.