Influenza A viruses are dynamically epidemic and genetically diverse. Due to the antigenic drift and shift of the virus, seasonal vaccines are required to be reformulated annually to match with the evolving virus. Targeting hemagglutinin, a key protein on the surface of the virus, is a promising approach for broad protection against influenza. This research activity aims to explore novel strategies for targeting hemagglutinin, with the ultimate goal of developing a universal influenza vaccine.