Hemidesmosomes are cell structures in the cell membranes which produce a connection between cells and the basal lamina.
You see electron microscopy like half desmosomes. Just like those they serve to stabilize the epithelial cells and are intracellularly associated with the intermediate filaments, but they do not combine different cells together, but link the basal surface of the epithelial cells to the underlying basal lamina. The extracellular adhesion molecules are not here desmogleins as with desmosomes but integrins. The extracellular domains of the integrin binding to laminin proteins of the basal lamina. Hemidesmosomes are particularly expressed by epithelial cells. The intracellular domain of the integrin via anchor proteins ( plectin ) to keratin filaments. In contrast to the desmosomes the ends of keratin filaments are often anchored on the hemidesmosomes.
Autoantibodies against hemidesmosomes lead to the clinical picture of bullous pemphigoid.