Isolation, production, and analysis of small leucine-rich proteoglycans in bone

Small leucine-rich proteoglycans (SLRPs) are a unique class of proteins that exist in the extracellular matrix, playing key roles in cell proliferation and function. In bone, SLRPs such as biglycan and decorin affect osteogenesis and bone remodeling. Their essential role in this organ system has created the need to isolate these proteins for study. Bone presents unique obstacles to the study of proteins; however, through the use of demineralizing agents, efficient methods of the purification of proteoglycans have been developed. Additionally, methods have been developed that allow for the production and isolation of proteoglycans from conditioned media, which opens the door to a wide array of in vitro and in vivo assays. In stride with the purification and utilization of proteoglycans is the need to insure proteoglycan identity and purity, which is accomplished through enzymatic deglycosylation and blot analysis.