ABSTRACT
The phenomenon of “rounding up” was predicted for a wide range of model parameters. When a cell makes contact with a surface or with another cell, there are a number of important considerations in determining whether adhesion results, in addition to those of equilibrium models. In some cases, the precise molecules responsible for the interactions are known, such as antibodies and antigens or neural cell adhesion molecules. Sometimes the interacting molecules give rise to specialized structures between the cells, such as desmosomes, tight junctions, and gap junctions linking epithelial cells. When a highly mobile cell such as a lymphocyte or macrophage, or a cell which spends a good portion of the time not in contact with other cells such as blood cells, adheres to another cell, this is probably best viewed as cell-cell adhesion. Lateral mobility of receptors in the plane of the cell membrane is an important variable in cell adhesion.
