Isolation of H and Leb active human salivary mucins and structures of their sugar chains with the H and Ley (Y) determinants.

Blood-group active mucins were prepared from an OLeb donor's saliva. Salivary proteins were carboxamidomethylated and fractioned on Sepharose CL-4B in the presence of sodium dodecyl sulfate. H and Leb active mucins were eluted at the void volume and were purified by Sepharose CL-2B chromatography. The purified mucins comprised 71% carbohydrate, 26% protein and 3.1% sulfate (by weight). Sugar chains of the mucins were released by alkaline borohydride treatment and fractionated by serial liquid chromatography. Three neutral oligosaccharides were isolated and submitted to sugar analysis and 1H-nuclear magnetic resonance spectroscopy. The following structures are proposed: Fuc alpha 1-2Gal beta 1-3[Fuc alpha 1-2Gal beta 1-4GlcNAc beta 1-6]GalNAcol, Fuc alpha 1-2Gal beta 1-3[Fuc alpha 1-2Gal beta 1-4[Fuc alpha 1-3]GlcNAc beta 1-6]GalNAcol and Fuc alpha 1-2Gal beta 1-3GlcNAc beta 1-3GalNAcol, which contain the H type 2, Ley (Y) and H type 1 determinants, respectively. The present report provides the first identification of some antigenic structures in human blood-group active salivary mucins.