| Abstract: | We introduce here a simple method which permits an efficient isolation of apical plasma membranes from tissue culture cells and the electron microscopic examination of their protoplasmic surfaces by use of the platinum/carbon replica technique. Different procedures were tested with regard to the efficiency of isolation and preservation of ultrastructure. Best results were obtained by prestabilization of cell surfaces with low concentrations of tannic acid prior to isolation. To demonstrate the possible applications and versatility of the method, studies were done on virus-infected cells in combination with immunocytochemical labeling. With this model system, we show that it is possible to correlate the structures seen on the cytoplasmic surface of the plasma membrane with the distribution of virus antigens at the cell surface labeled with immunogold markers prior to preparation. |
