Poly-N-acetyllactosamine carbohydrate epitope (Poly-LacNAc)

Poly-N-acetyllactosamine is a linear carbohydrate epitope consisting of repeating N-acetyllactosamine disaccharide units (Galβ(1,4)-GlcNAcβ(1,3)-)_n_. These structures are present on both N- and O-linked glycoproteins and glycolipids on mammalian cells. They serve as backbone polymers for further glycan branching and are recognized by galectins, which mediate cell-cell adhesion, immune responses, and tumor metastasis. Poly-LacNAc is biosynthesized by the sequential action of β1,3-N-acetylglucosaminyltransferases (e.g., B3GNT2) and β1,4-galactosyltransferases. Its expression and modification are dynamically regulated and linked to development, inflammation, infection, and cancer.

Other names

poly-LacNAcpoly-N-acetyl-lactosaminepoly(N-acetyllactosamine)N-acetyllactosamine polymer

Recognition by lectins (particularly galectins) can mediate cell signaling, immune modulation, or promote cancer cell aggregation/dissemination. Basis of selectivity for glycan-binding molecules in diagnostics and some emerging therapies.