Epiligrin, a new cell adhesion ligand for integrin alpha 3 gamma 1 in epithelial basement membranes

Epiligrin is a new glycoprotein in most epithelial basement membranes and is a ligand for cell adhesion via integrin alpha 3 beta 1. In the extracellular matrix of human foreskin keratinocytes, epiligrin contains three disulfide-bonded, glycoprotein subunits, E170, E145, and E135, based on molecular size in kilodaltons. Epiligrin, immunopurified with MAb P1E1, induced cell adhesion and localization of integrin alpha 3 beta 1 in focal adhesions. Cell adhesion to epiligrin was inhibited with an anti- alpha 3 beta 1 MAb. Epiligrin also colocalized with integrin alpha 6 beta 4 in hemidesmosome-like stable anchoring contacts.