Used in immunological research to study liver cancer and hepatocellular carcinoma due to GPC3's role as a tumor-associated antigen. The mutated form (S495A, S509A) prevents phosphorylation, allowing researchers to distinguish the role of phosphorylation in GPC3 function and enhancing protein stability. This makes it ideal for antibody binding assays, immunoassay development, and vaccine research. The His Tag allows for easy purification and detection. Commonly used in generating monoclonal antibodies and evaluating targeted therapies in preclinical models involving cynomolgus or rhesus macaque systems.