• This is C2GnT-1 or C2GnT-L (leukocyte type) or core-2 GlcNAcT that forms the core-2 branch on O-glycans. It is widely expressed in human leukocytes and also other tissue.
• Its level is low in naive T-cells but increases upon T-cell activation.
• C2GnT-I upregulation also promotes metastasis in colorectral, lung and prostate cancer.
• C2GnT-I is a major contributor to L- and P-selectin binding during inflammation.
• Addition of sulfotransferase activity can result in the formation of 6-sulfo sialyl Lex structures on these core-2 glycans that act as L-selectin ligands in the HEV.
• GCNT1 is over-expressed in some diseases Wiskott-Aldrich syndrome (WAS), leukemia and AIDS. This contributes to immunodeficient conditions due to abherent T-cell function.
• Core2 branch is a scaffold for the subsequent production of lactosamine disaccharide repeat, poly-N-acetyllactosamine (Galβ1-4GlcNAc)n which is a ligand for galectin-3.
• Core-2 branch in general adds bulk to the O-glyans and this may reduce other interactions like TRAIL binding to DR4-- thus it is immunomodulatory.