Galβ1-4GlcNAcβ1-3Galβ1-4GlcNAcβ1-3Galβ1-4GlcNAc

Galβ1-4GlcNAcβ1-3Galβ1-4GlcNAcβ1-3Galβ1-4GlcNAc  (pentasaccharide poly-LacNAc type 2 chain) forms a linear, repeating N-acetyllactosamine backbone critical for cell adhesion, immune recognition, and tumor metastasis research, appearing as a white lyophilized powder used in glycan microarray standards and selectin ligand studies. This i-antigen precursor (also called VIM-2 pentasaccharide) features three sequential β1-4Gal-GlcNAcβ1-3 disaccharides on a reducing GlcNAc terminus, serving as high-affinity E-selectin/P-selectin ligand for leukocyte rolling during inflammation while binding macrophage galectin-3 for tumor immune evasion; commercially synthesized via β4GalT/β3GnT cascades (>97% purity), it demonstrates gastric stability, selective enzymatic extension to sialyl-Lewis structures, and roles in cancer glycomimetics, stem cell differentiation markers, and anti-metastatic drug screening, with ambient shelf stability exceeding 48 months. Appearance White amorphous lyophilized powder, odorless and non-hygroscopic. Freely water-soluble (>400 g/L); clear solutions pH 6-8. ​ Source Abundant in human poly-LacNAc chains on leukocytes, erythrocytes (adult i-antigen). Enzymatic synthesis using alternating β1-4 galactosyl/β1-3 N-acetylglucosaminyl transferases. ​ Molecular Weight and Structure 1100.98 g/mol (sodium form), formula C₄₂H₇₁N₃O₃₁. [Galβ1-4GlcNAcβ1-3]₃Galβ1-4GlcNAc linear repeating type 2 chain. ​ Sugar Specificity Binds E-selectin, P-selectin, siglec-3/5 via poly-LacNAc backbone. Substrates for α2-3/6 sialyltransferases, α1-3 fucosyltransferases (sLeX formation). ​ Biological Activity Mediates leukocyte extravasation; galectin-3 ligand for tumor metastasis. Prebiotic for Bacteroides promoting butyrate production; anti-inflammatory. ​ Purity and Microbial Contamination ≥97% anomeric HPLC/NMR; endotoxins <2 EU/mg. Sterile filtered; heavy metals <0.5 ppm, moisture <3%. ​ Identity and Quality Control ¹H-NMR confirms β-linkages (Gal H1 4.4-4.6 ppm); LC-MS [M+2Na]²⁺ 572. HPAEC monosaccharide ratio Gal:GlcNAc 3:2; linkage analysis. ​ Shelf Life and Storage 48+ months ambient desiccated; 5+ years -20°C lyophilized. Avoid extreme pH (>9) or hydrolases. ​ Applications Selectin inhibitor screening; cancer glycan biomarkers. Stem cell surface marker research; glycoengineering scaffolds. ​ Key Characteristics Linear scaffold for glycan extension; high selectin avidity. Type 2 chain specificity vs branched type 1; gastric-stable. ​ Citation Links https://pubchem.ncbi.nlm.nih.gov/compound/71297720 ​ https://pubchem.ncbi.nlm.nih.gov/compound/172642668 ​ https://alpha.glycosmos.org/organisms/10066/glycans ​ https://www.sciencedirect.com/science/article/pii/S0021925819367900 ​ https://academic.oup.com/glycob/article-pdf/13/5/387/1648069/cwg044.pdf ​ https://oro.open.ac.uk/38117/1/c1sc00120e.pdf ​ https://pubchem.ncbi.nlm.nih.gov/compound/156613025 ​ https://mcawdb.glycoinfo.org/detail.html?296 ​ https://glycosmos.org/structure/poly-LacNAc ​