Terminal galactose residue on cell-surface glycan

Terminal galactose residues on cell-surface glycans are carbohydrate motifs frequently found at the end of glycan chains attached to proteins and lipids. In therapeutic monoclonal antibodies, terminal β1,4-galactose residues at specific positions of the Fc N-glycans significantly impact antibody stability and effector functions by modulating interactions with immune receptors, such as FcγRIIIa, and by influencing complement activation. The location and structure of these galactose residues are crucial for the biological activity of antibodies and are carefully monitored in the development of biotherapeutics due to implications for efficacy, safety, and batch consistency. Beyond antibodies, terminal galactose is a key recognition motif in cell–cell interactions, can be modified (e.g., sulfated), and its altered expression or structure is linked to certain cancers, infections, and inflammatory diseases. Detection or manipulation of terminal galactose residues is useful for biomarker development and therapeutic antibody engineering rather than direct receptor targeting.

Other names

Galactose-terminated glycanterminal Gal residueβ1,4-galactose on N-glycangalactosylated glycanterminal galactose moiety

Antibodies with galactosylated Fc regions can have enhanced FcγRIIIa binding and altered antibody-dependent cell-mediated cytotoxicity (ADCC) and complement-dependent cytotoxicity (CDC); Drugs may modulate glycosylation enzymes, indirectly affecting terminal galactose expression