Cell adhesion: a general appraisal.

Most data on cell adhesion relate to in vitro conditions; for this reason the subject of this review is adhesion of cells to plane inorganic substrata. Adhesion is conceived of as a process requiring energy and comprising distinct steps, most notably the secretion of attachment proteins, the build-up of attachment sites, and the attachment site--induced organization of the cytoskeleton. The grip and stick concept (Rees et al. 1977) is a very adequate interpretation of this course of events. Agents and functions involved in the stages of adhesions are briefly outlined and a few possible extrapolations to cell adhesion in vivo are indicated.