A majority of suppliers have reported the clone G4E4 to be a mouse monoclonal antibody specific to the human gene, RBP4, or Retinol binding protein 4. Other suppliers describe clone G4E4 to be a mouse monoclonal antibody against human RBP1, or retinol binding protein 1. Suppliers have reported additional species reactivites for the target of this clone, including goat, mouse, primate, rabbit, and rat. Indicated applications for antibody clone G4E4 include Western blot, immunohistochemistry, immunofluorescence, ELISA, immunocytochemistry, and immunoprecipitation.