Carbohydrate differentiation and cancer-associated antigens detected by monoclonal antibodies.

action was the pluripotential haemopoietic stem cell (CFUS ) . Whenever they were tested, free glycosaminoglycan chains were unable to reproduce P-D-xyloside influences on cell behaviour. On the basis of the cited biochemical evidence it seems likely that the xyloside effects are mediated through alterations in surface membrane proteoglycans. Most probably the xyloside-induced changes follow from a reduction in proteoglycan concentration in the extracellular matrix and/or the associated tissue fluids. It should also be remembered that, in contrast to the humble sea urchin, xyloside influences on the formation of nuclear proteoglycans in mammalian systems have not been investigated and represent an important area for future studies. Nevertheless, the use of P-D-xylosides has emphasized the great significance of proteoglycans in normal cellular proliferation and morphogenesis and these sugar derivatives will remain powerful tools for further experiments at the molecular and cellular levels.