H-2 antigen on cell membranes: an explanation for the alteration of distribution by indirect labeling techniques.

The distribution of H-2 isoantigens on the plasma membrane of lymphocytes and thymocytes was studied with ferritin-conjugated alloantibody. The spatial arrangement of the membrane components which possess H-2 isoantigens is markedly altered by the attachment of a second antibody, directed toward mouse gamma globulin or ferritin; the second anitibody appears to cause the aggregation of the sensitized H-2 antigens into discrete zones on the cell membrane. Other membrane antigens may be equally affected by indirect labeling techniques and, thus, topographic analysis of the antigenic structure should be done with antibody that is directly conjugated.