EVALUATION OF RED-BLOOD-CELL LYSING SOLUTIONS FOR THE DETECTION OF INTRACELLULAR ANTIGENS BY FLOW-CYTOMETRY

When analyzing leukocyte cell surface antigens by now cytometry, leuko cytes are usually first labeled in whole blood and the red blood cells are finally lysed with lysing solutions. The erythrocytes are lysed, but the leukocytes are expected to remain intact. Six commercial red b lood cell lysing methods were investigated for possible leukocyte perm eabilization effect. The effectiveness of permeabilization was studied by propidium iodide staining, and the detectability of intracellular antigens was studied by using monoclonal antibodies toward two model a ntigens. Most of the lysing methods caused permeabilization of at leas t part of the leukocytes, but only one method, already found in our pr evious studies, was applicable for complete permeabilization of leukoc ytes and for detection of intracellular antigens alone or simultaneous ly with the cell surface antigens. (C) 1995 Wiley-Liss, Inc.