Lectin microarray analyses reveal host cell-specific glycan profiles of the hemagglutinins of influenza A viruses.

Glycan structures on hemagglutinin (HA) of influenza A viruses have been analyzed previously to understand their significance. However, the formerly established methods using mass spectrometry present disadvantages such as procedure complexity, sensitivity, and throughput. Our study has established a novel method for analyzing glycan profiles of HA using lectin microarray techniques. We successfully obtained glycan profiles of HA starting from 1 ml of the 106 TCID50 samples through simple antigen enrichment using optimized immunoprecipitation. The profiles were reasonably consistent with known glycan structures of HA. Next, we compared glycan profiles of the HAs prepared from chicken embryos, MDCK, Vero, and A549 cells, and demonstrated the host cell-specific HA glycan profiles. Notably, the HA from MDCK cells was α1-3 galactosylated. Our method provides a highly sensitive and simple procedure for glycan profiling of the viral glycoproteins, thereby paving way for direct glycan analyses of human- and animal-derived virions.