5-[(2-O-A-D-Glucopyranosyl-b-D-galactopyranosyl)oxy]-L-lysine is a bone formation and bone resorption marker that is related to bone turnover processes during growth and development as well as metabolic bone diseases; it is also involved with reactions associated with the functional expression of human mannan-binding proteins (MBPs) in human cell lines transfected with MBP cDNA.