ABSTRACT
Adhesion molecules have been demonstrated to be capable of effecting various prominent interactions. The initial descriptions of cell surface “adhesion molecules” in the early 1980s ushered in an era of exponential discovery. The name integrins derives from the concept that these molecules “integrate” information from the extracellular milieu to intracellular compartments. The selectins, so named because they are selectively expressed on cells related to the vasculature and contain a lectin-binding domain, are composed of three extracellular domains: one of complement regulatory protein-like short consensus repeat units, an epidermal growth factor (EGF)-like domain, and the amino-terminal lectin domain that confers binding specificity. The EGF and complement-like domains may function primarily as a scaffold— optimally positioning the lectin domain above the cellular glycocalyx, thereby facilitating its interaction with ligand. The immunoglobulin superfamily is phylogenetically ancient, having been described in insects, where they have been shown to function as adhesion receptors in nervous system development.
