Expression patterns of complex glycoconjugates and endogenous lectins during fetal development of the viscerocranium

Experimental evidence suggests that carbohydrates and their corresponding r eceptors (endogenous lectins) decode biological information. Therefore, the expression of complex oligosaccharides - the potential ligand part of this recognition system - during chondrogenesis and osteogenesis was determined in the viscerocranium of fetal rats by mapping the staining patterns of ex ogenous lectins. Results were compared with the expression of bone- and/or cartilage-specific core proteins and the binding profiles of neoglycoconjug ates. These synthetic tools make possible the localization of sugar-ligand- binding sites. The spatial and temporal distribution patterns of glycoconju gates were highly dynamic and demonstrated a clear correlation with charact eristic morphological modifications. The glycobiological characterization o f precartilage mesenchymal cells revealed distinct differences compared to prospective bone anlagen. Especially the binding of the exogenous lectin fr om Griffonia simplicifolia II, that selectively visualized prechondral aggr egations, reveals that regulation of early chondral growth is at least phen omenologically correlated with a relatively atypical oligosaccharide compos ition terminating with N-acetylglucosamine.