Detection of erythrocyte membrane structural abnormalities in lecithin: Cholesterol acyltransferase deficiency using a spin label approach

Abstract
The membrane fluidity of erythrocytes from patients with Lecithin: cholesterol acyltransferase (LCT) deficiency was studied by means of electron spin resonance. The temperature dependence of the separation of the outer extrema of the spectra of 2-(3-carboxy-propyl)-4,4-dimethyl, 2-tridecyl-3-oxazolidinyloxyl spin probe was monitored for normal, presumed carrier and clinically affected subjects. The temperature profile of controls was significantly different form that of the presumed carriers and the clinically affected individuals. The results show that the compositional abnormalities previously noted in erythrocyte membranes from patients with LCAT deficiency are associated with alterations in the physicochemical state of the membrane. An investigation of the spectral lineshapes below 10°C allowed a distinction to be made at the membarne level between clinically affected subjects and clinically normal heterozygous carriers. Alterations in the temperature dependence of electron spin resonance parameters may provide a sensitive index of red cell membrane alterations in pathological states of generalized membrane involvement.