ABSTRACT
Cell-cell interaction is a critical process in both the developing and mature nervous systems and it is mediated by cell surface glycoproteins, which may mediate their adhesive properties by either homophilic or heterophilic binding. The expression of these glycoproteins may be regulated both spatially and temporally to reflect the differential adhesive requirements of the neural cells at specific developmental stages (Breen et al., 1998). The neural developmental process can be divided into four distinct stages, with individual cell surface proteins playing a pivotal role in one or more of these processes. These are: (1) cell proliferation, (2) cell aggregation, (3) cell differentiation, and (4) synaptogenesis. In addition, cell surface glycoconjugates also play a major role in modulating neural regeneration and synaptic plasticity in the mature nervous system (Fazeli et al., 1994; Langenfeldoster et al., 1994; Lüthl et al., 1994; Smith et al., 1994). Morphoregulatory molecules include cell adhesion molecules (CAMs), the substrate adhesion molecules (SAMs) and their receptors (e.g., integrins), and cell junctional molecules (CJMs) (Cunningham, 1991).
