Chemically induced cell fusion in vitro of erythrocytes from patients with liver diseases [proceedings

Abstract

The increased cell diameter and osmotic resistance of erythrocytes from patients with hepatobiliary diseases is associated with an increased content of cholesterol, and to a lesser extent an increase in phosphatidylcholine, of the cells (Cooper & Jandl, 1968; Werre et al., 1970). It has been demonstrated by freeze-etch electron microscopy that the lipid-rich abnormal lipoprotein LP-X found in cholestasis can fuse with erythrocyte membranes (Verkleij et a/., 1976). Intercellular fusion of hen erythrocytes can be induced by chemical fusogens such as glycerol mono-oleate (Ahkong et a/., 1973). We have shown that enrichment of hen erythrocytes with cholesterol from liposomes strikingly increases their susceptibility to fusion by chemical fusogens and by Sendai virus (M. J. Hope, K. R. Bruckdorfer & J. A. Lucy, unpublished work). In the present study, erythrocytes of abnormal lipid composition obtained from patients withavariety of hepatobiliary disorders were compared with cells from healthy control subjects with respect to fusion induced by glycerol mono-oleate. Venous-blood samples, all taken on the same day, were obtained from six patients with either alcoholic cirrhosis, acute drug-induced hepatitis, extrahepatic cholestasis, primary biliary or cryptogenic cirrhosis, and from four controls. Each sample of packed erythrocytes, which was washed three times in a citrate anti-coagulant solution (De Gowin etal., 1949), was divided for extraction and analysis of lipids, and counting of cell numberswith a Coultercounter. Anevaluationof fusion in triplicateafterincubationwith ultrasonically dispersed glycerol mono-oleate (200mM) in a modified Eagle’s medium at 37°C was made as described previously (Ahkong et al., 1973). The percentage polykaryocytosis (number of cells involved in fusion expressed as a percentage of the total cell number) was determined by observation with a Zeiss standard WL phase-contrast