Different integrins mediate cell spreading, haptotaxis and lateral migration of HaCaT keratinocytes on fibronectin.

Collaborative role of various fibronectin-binding integrins (alpha5beta1, alphavbeta1 and alphavbeta6) as mediators of cell adhesion and migration on fibronectin was studied using cultured HaCaT keratinocytes. This cell line spontaneously expressed all three fibronectin-binding integrins. In addition, the expression of alphavbeta6 integrin was strongly and specifically upregulated by transforming growth factor-beta1 (TGFbeta1) whereas the amount of other integrins remained practically unchanged on the cell surface.

Laminin-5 expression is independent of the injury and the microenvironment during reepithelialization of wounds.

We examined the expression of laminin-5 and its integrin receptors during reepithelialization of human wounds. We used suction blisters of skin as a model of keratinocyte migration on a basement membrane matrix and mucosal full-thickness wounds as a model in which keratinocytes migrate in a provisional matrix. An animal model, in which human epidermal keratinocytes were injected into the back of athymic mice, was used to follow the deposition of the basement membrane components.