Artefacts produced during plasma-membrane isolation. I. Cell disruption causes alterations in the structure of the plasma membrane of thymocytes

Abstract Three different methods of cell disruption and plasma membrane isolation without using membrane-stabilising agents, have been compared in order to study whether heterogeneity of the plasma membrane is a natural phenomenon or is induced by cell disruption. The plasma membrane isolated from thymocytes shows an altered structure when compared with the plasma membrane of intact cells. Freeze-etch studies demonstrate an aggregation of intramembranous particles and a decrease in their number. These results are discussed in relation to heterogeneity of the cell surface.