A majority of suppliers have reported the clone CATA-1 to be a mouse monoclonal antibody specific to the human gene, HLA-A, or Major histocompatibility complex, class I, A. Other suppliers describe clone CATA-1 to be a mouse monoclonal antibody against human HLA-B, or major histocompatibility complex, class I, B. Indicated applications for antibody clone CATA-1 include immunohistochemistry, flow cytometry, and immunofluorescence.