Fig. 3

The results of the solid-phase binding assay for H4N1 AIVs. The assay quantified the viruses’ direct binding capacity to sialylated glycopolymers that contained either α2,3 sialic acid (depicted in red) or α2,6 sialic acid (depicted in blue). Each data point represents the mean of three independent replicate experiments. (a-c) showed that CS01, CS01-A4, and CS01-A7 demonstrated the capability to bind to α2,3 sialic acids. Additionally, all three viruses were capable of binding to α2,6 sialic acids, and compared to CS01-A4 and CS01-A7, the binding affinity of CS01 is relatively weak. As a control, the human influenza virus F283-H1N1 binds exclusively to α2,6 sialic acids (d), while the AIV E006-H9N2 primarily binds α2,3 sialic acids (e)