LIPID A BINDING AND DEFORMABILITY OF ADULT RED-BLOOD-CELLS

Lipid A is responsible for the endotoxic activities. The effect of different lipid A concentrations and incubation times on red blood cell (RBC) deformation was studied by means of a rheoscope. Lipid A concentrations Of 10 and 100 mug/ml decreased RBC deformability by 41% and 46%, respectively, after 20 min of incubation. After 1 h, RBC deformability nearly reached preincubation values. Lipid A binding to RBC membranes (passive hemolysis test) was similar after 30 and 60 min incubation. This suggests that lipid A binding to RBC membrane does not change during this time, but that lipid A is inserted into the membrane, thereby improving RBC deformability.