The tensegrity model applied to the lens: a hypothesis for the presence ofthe fiber cell ball and sockets

The concept of tensegrity refers to the tensional integrity of a system. Su ch a system mechanically stabilizes itself by balancing the opposing forces of tension and compression. One category of this model involves a 'pre-str essed' condition in which the structural elements are in a state of tension al compression. The other category includes rigid struts that can sustain t he opposing forces. The lens of the eye contains epithelial cells that diff erentiate at the lens equator to fiber cells. With time, these fiber cells are packed into the center of the lens or the lens nucleus. Part of the pro cess of differentiation is the loss of the cellular nucleus and organelles, During maturation of the lens fiber cells, much of the cytoskeleton is los t as a result of proteolysis. As the lens cells mature, ball and socket joi nts and interlocking ridges appear on the cellular surface. Applying the te nsegrity model to the lens, it appears that the lens cells go from prestres sed state of tensional compression to the other state that is defined by ri gid connections between cells. (C) 2000 Harcourt Publishers Ltd.