Lens culinaris lectin receptors in the plasma membrane of rat liver cells: comparative electron microscopic studies on normal cells, on cells in vivo transformed by diethylnitrosamine and on Zajdela ascites hepatoma cells.

The distribution of the Lens culinaris lectin receptors on normal rat liver cells, on rat liver cells in vivo transformed by diethylnitrosamine and on Zajdela ascites hepatoma cells of the rat is investigated by means of the Lens culinaris lectin-peroxidase method and by ferritin conjugated Lens culinaris lectin. The normal rat liver cells show a continuous labeling at the outer membrane surface by the lectin complexes, whereas the transformed rat liver cells exhibit a strong tendency for patchy distribution of the cell surface label. The discontinuous cell surface label in the transformed rat liver cells is obviously caused by an internalization of plasma membrane areas. The importance of these morphological findings in their relationship to Lens culinaris lectin mediated agglutination of rat liver cells and the membrane fluidity in general are discussed. In the experiments no hints to a rotation of the Lens culinaris lectin receptors from the outer membrane surface to the inner membrane surface of rat liver cells can be found.