CYTOPLASMIC AS OPPOSED TO SURFACE IA-ANTIGENS EXPRESSED ON HUMAN PERIPHERAL-BLOOD LYMPHOCYTES AND MONOCYTES

  • 1 January 1982
    • journal article
    • research article
    • Vol. 49  (2) , 355-363
Abstract
Human peripheral blood leukocytes were examined for the presence of HLA-Dr or Ia-like antigen on the cell surface and in the cytoplasm. Surface staining of viable cell suspensions, using monoclonal anti-Ia antibody in both immunofluorescence and immunoperoxidase methods gave similar results. Using a newly developed immunoperoxidase double staining procedure, which stains the cells when either viable or fixed, both the surface and cytoplasm of the individual cells were labeled and examined. Of the mononuclear cells 20-30% were positive for Ia staining on the cell surface and in the cytoplasm. Morphologically these positive cells were identified as both lymphocytes and monocytes. A small percentage (5-9%) of these monocytes and lymphocytes consistently labeled only cytoplasmic Ia determinants. Only surface binding was observed with monoclonal antibodies recognizing T cell subpopulations. The ability to detect intracellular Ia antigenic determinants is of value in distinguishing stages of lymphocyte and monocyte development.