Lipid composition of Schistosoma mansoni and surface labeling of glycolipid components.

Abstract

Schistosoma mansoni adult worms obtained from human patients and mice infected with cercariae were compared in lipid composition. Both worms possessed cholesterol ester, free fatty acid and cholesterol as neutral lipids, but the latter worms possessed triacylglyceride as another component. Phospholipid compositions of both worms were similar. Larger amounts of phosphatidyl choline diacylglyceride and smaller amounts of phosphatidyl ethanolamine diacylglyceride were detected. Adult worms from infected mice were surface-labeled by galactose oxidase treatment followed by sodium boro[3H]hydride reduction after or before trypsin treatment. Trypsin treatment was approximately 10 times more effective to label glycolipids than non-treatment. Mono-, di-, tri- and tetra-glycolyl components were labeled with trypsin treatment; however, mainly tri-glycolyl glycolipid was labeled without trypsin treatment. These results indicated that some glycolipid components are really exposed on the surface of the tegumental membrane. But no antigenicity was detected in the purified neutral and acidic glycolipid fractions by the Ouchterlony's double diffusion test using rabbit anti-S. mansoni sera or those obtained from patients with S. mansoni infection, though these sera, each gave two different precipitin lines against homogenate of the adult worms.