Neuroglycobiology: Role of glycans in neurobiology and neuroscience glycoconjugate antigens in neural stem cells

The nervous tissue is composed of neurons, which transmit impulses, and glia (i.e., astrocytes and oligodendrocytes), which provide support and protection for the neurons. The central nervous system (CNS), including the brain and the spinal cord, is generated from progenitor cells that are recognized as neural stem cells (NSCs). NSCs are undifferentiated neural cells characterized by high proliferative potential and the capacity for self-renewal with retention of multipotency to differentiate into neurons and glia. Throughout neural development, NSCs undergo cellular differentiation and proliferation, and dynamic changes are observed in the composition of carbohydrate-rich molecules, including glycolipids, glycoproteins, and proteoglycans, that are expressed primarily on the outer surface of plasma membranes. The structural diversity of the carbohydrate moieties renders them ideally suited as stage-specific biomarkers for various cell types. More importantly, these molecules are increasingly recognized to play crucial functional roles in cell proliferation, differentiation, interaction, migration, and signal transduction. This chapter provides an introduction to some of the major carbohydrate-rich molecules [stage-specific embryonic antigen-1 (SSEA)-1; human natural killer-1 (HNK-1) antigen; and the ganglioside, GD3] in NSCs and presents current approaches to elucidate their functions in NSCs.