L-fucose, also referred to as 6-deoxy-L-galactose, is a monosaccharide that is a component of some N- and O-linked glycans and glycolipids in animals. (See Becker and Lowe, Glycobiology 13:41 R-51R (2003).) Fucose is typically added as a terminal modification to glycans, including glycans attached to blood group antigens, selectins and antibodies. Fucose can be attached to glycans via α(1,2)-, α(1,3)-, α(1,4)- and α(1,6)-linkages by specific fucosyltransferases. α(1,2)-fucose linkages are typically associated with the H-blood group antigens. α(1,3)- and α(1,4)-fucose linkages are associated with modification of LewisX antigens. α(1,6)-fucose linkages are associated with N-linked GlcNAc molecules, such as those on antibodies.
Fucosylation of proteins is believed to play a role in mammalian development. Mice homozygous for a targeted mutation of the FX gene exhibit pleiotropic abnormalities including a lethal phenotype. Reduced recovery of mice from heterozygous crosses was also reported. (Becker et al., Mammalian Genome 14:130-139 (2003). Aberrant protein fucosylation has been proposed to be associated with human disease, including up-regulation of sialyl LewisX and sialyl Lewisy in cancers. These glycans are ligands for E- and P-selectin molecules. In it speculated that increases in sialyl LewisX and sialyl Lewisy glycans on cancer cells increases metastases through interaction with E- and P-selectins on endothelium. Increased fucosylated glycans have also been observed in patients with rheumatoid arthritis. Currently, however, there are no approved therapeutic approaches targeting protein fucosylation levels.
USPTO Backgrounds
USPTO Backgrounds