Five specificity patterns of (1 → 3)-α- l-fucosyltransferase activity defined by use of synthetic oligosaccharide acceptors. Differential expression of the enzymes during human embryonic development and in adult tissues

The use of synthetic trisaccharides as acceptors led to the definition of five main (1 → 3)-α- l-fucosyltransferase activity patterns in human adult tissues: ( I), Myeloid cells, granulocytes, monocytes, and lymphoblasts, transfer an α- l-fucopyranosyl group to O-3 of a 2-acetamido-2-deoxy- d-glucosyl residue of H blood-group Type 2 oligosaccharide [α- l-Fuc p-(1 → 2)-β- d-Gal p-(1 → 4)-β- d-Glc pNAc→R] with Mn 2+ as activator. ( II) Brain has the same acceptor specificity pattern as myeloid cells, but can also use Co 2+ as activator. ( III) Plasma and liver transfer an α- l-furopyranosyl group to H blood-group Type 2 and to sialyl- N-acetyllactosamine [α-NeuAc-(2 → 3)-β- d-Gal p-(1 → 4)-β- d-Glc pNAc → R]. ( IV) Intestine, gall bladder, kidney, and milk have the same activity as ( III), but also transfer an α- l-fucopyranosyl group to O-4 of a 2-acetamido-2-deoxy- d-glucose residue of H blood-group Type 1[α- l-Fuc p-(1 → 2)-β- d-Gal p-(1 → 3)-β- d-Glc pNAc→R] and sialyl Type 1 [α-NeuAc-(1 → 3)-β- d-Gal pNAc → R].( V) Stomach mucosa is not able to use sialyl- N-acetyllactosamine, but can transfer an α- l-fucopyranosyl group to the other Type 1 and Type 2 acceptors. Unlike in adult tissue, a single myeloid-like pattern of (1 → 3)-α- l-fucosyltransferase activity was found at early stages of development in all tissues tested. This embryonic enzyme is later progressive replaced by enzymes or mixtures of enzymes having the corresponding adult patterns of enzyme expression. All lymphoblastoid cell lines and half of the tumor epithelial cell lines tested expressed the myeloid-like pattern of enzyme found in normal embryonic tissues. The remaining tumor epithelial cell lines expressed different forms of (1 → 3 4 )-α- l-fucosyltransferase acceptor specificity patterns.