This antibody recognizes the largest (49 kDa) of the three variants of the CD1 heavy chain, designated as CD1a. The 49 kDa polypeptide is associated with b2-microglobulin on human cortical thymocytes, dendritic cells and Langerhans' cells. It may also be expressed on some T cell leukemias and lymphoma. The antibody does not react with peripheral blood T and B lymphocytes, monocytes, normal bone marrow mononuclear cells or normal tonsillar T and B lymphocytes.
CD1a antigen is expressed on human cortical thymocytes, dendritic cells in peripheral lymph nodes and Langerhans' cells in normal, dysplastic and neoplastic tissue. CD1 has a domain organisation similar to that of MHC Class I and its expression is inversely correlated with that of TCR and MHC Class I.Synonyms: T-cell surface antigen T6/Leu-6, T-cell surface glycoprotein CD1a, T6/Leu-6, hTa1, hTa1 thymocyte antigen