Anti-HA monoclonal antibody is another widely used research reagent that targets the HA (hemagglutinin) peptide tag. The HA tag is a short amino acid sequence (YPYDVPDYA) derived from the influenza virus hemagglutinin protein. Similar to the Flag tag, the HA tag can be fused to the N- or C-terminus of a protein of interest to facilitate its detection, purification, and analysis. Key Applications of Anti-HA Monoclonal Antibody: Protein Detection: Western blotting: Used to detect and quantify the expression of tagged proteins. Immunoprecipitation: To isolate tagged proteins from complex mixtures. Immunohistochemistry: For visualizing tagged proteins in cells and tissues. Flow cytometry: To analyze the expression of tagged proteins on cell surfaces. Protein Purification: Affinity chromatography: The HA tag can be used to purify tagged proteins using anti-HA affinity columns. Protein Localization: Immunofluorescence microscopy to visualize the subcellular localization of tagged proteins.