Effects of Surface Proteins of Human Erythrocyte Membrane on the Interaction with Lipopolysaccharidesfrom Escherichia coli 055:B5

摘要

The role of erythrocytic surface membrane proteins and membrane charge in the interactions of theerythrocytes with lipopolysaccharides (LPS) isolated from Escherichia coli 055:B5 (LPS-(E.coli),S-form) hasbeen examined by two independent methods, flow cytometry and cell electrophoresis. Treatment of erythro-cytes with trypsin that modifies stereochemical properties of cell surface resulted in a 16% increase in the levelof the erythrocyte fluorescence measured after their incubation with fluorescently labeled LPS_(E.coli).Electro-phoretic mobility (EM) of the trypsin-treated erythrocytes was reduced by 16%. The removal of sialic acidsfrom the erythrocyte surface with neuraminidase had no considerable effect either on the relative EM values orfluorescence intensity after the incubation of cells with LPS. The results suggest that the major role in the incor-poration of the S-form LPS into the membrane of human erythrocytes is played by stereochemical factors,whereas the cell surface charge is less significant.