Integrins of normal human epidermis: differential expression, synthesis and molecular structure

Abstract

The expression of integrin cell surface receptors in normal skin and their synthesis and molecular structure in keratinocyte cultures was investigated. The reactivity of four different polypeptides of the integrin family (α²‐,α³‐,α⁶‐ and β₁‐chains) was demonstrated in the basal cell layer of normal epidermis. Studies of labelled keratinocyte cell lines showed that the polypeptides were expressed as α²β₁, α³β₁ and α⁶β₄ integrins. Only the α⁶β₄ integrin showed polarization towards the basement membrane attachment site of basal layer keratinocytes, and was preferentially expressed at microvillous projections. In contrast, α²β₁ and α³β₁ integrins were equally expressed throughout the basal cell plasma membrane.