Immunolocalization of laminin during estrogen-induced differentiation of quail oviduct epithelial cells.

During estrogen-induced development of the quail oviduct, tubular glands are formed by evagination of epithelial cells into the stroma. The distribution of laminin was studied during the early stages by means of immunofluorescence and immunoperoxidase techniques. Ultrastructural changes in the basal lamina were studied by electron microscopy. Basement membranes at all stages of development were delineated with 3 polyclonal antilaminin antisera. However, in ovariectomized birds, laminin could not be detected by one of the polyclonal antilaminin antisera. Subsequently, this antibody detected laminin as epithelial cell evaginations were induced by estradiol benzoate. The heavy and light chains of Engelbreth Holm sarcoma (EHS) laminin were revealed in immunoblotting by all antibodies. By electron microscopy after the immunoperoxidase technique with antilaminin antisera laminin appears to be accumulated mainly in the lamina densa. Furthermore, the thickness of the basal lamina increases during oviduct development. These data indicate that basal lamina organization is modified during oviduct cell differentiation and that immunoreactivity of epithelial basement membrane laminin changes during development.