Human blood group activity of human and canine intestinal glycolipids containing fucose.

A number of fucose-containing glycolipids (fuco-lipids), which are similar in composition to those of human normal and malignant gastrointestinal tissue, have been isolated from whole small intestines of individual dogs. Dogs from which these fuco-lipids were isolated fell into two types according to the qualitative sugar composition of their fuco-lipids. Glycolipids from type I dogs contained glucose, galactose, glucosamine, galactosamine and fucose, while those from type II dogs contained the same sugars but lacked galactosamine. Fucolipids isolated from type I and II dogs were tested for both canine blood group and human A, B, H and Le and Le blood group activity. At the concentrations tested, only human blood group A activity was found in significant amounts, and only in those fuco-lipids which contained galactosamine (type I dogs). Of the fuco-lipids with human blood group A activity, some had activity comparable to that of glycoprotein blood group substances, while others had lower, but significant, activity. These latter fuco-lipids also had marked chromatographic differences, indicating that they are of several different structural types, a finding similar to the A active glycolipids of human red cell stroma. None of the isolated intestinal fuco-lipids had canine blood group activity. A fuco-lipid with Le activity was also isolated in relatively large amounts from a normal human whole small intestine.