Immunolocalization of desmoglein I ("band 3" polypeptide) on acantholytic cells in pemphigus vulgaris, Darier's disease, and Hailey-Hailey's disease.

Acantholysis is defined as loss of coherence between epithelial cells and is histologically shown in several bullous diseases. It was postulated that desmoglein I, one of the major transmembrane glycoproteins of the desmosome, may adhere to the attachment plaque inside the cell and contribute to desmoglea outside the cell. In this study we used a well characterized antibody against desmoglein I for immunofluorescence and immunoelectron microscopic techniques on 2 cases each of pemphigus vulgaris and Darier's disease and one case of Hailey-Hailey's disease. In the normal epidermis desmosomes were demonstrated in dotted or rim-like patterns along cell periphery on immunofluorescence study. In pemphigus vulgaris dotted or rim-like patterns were still identified in many acantholytic cells, particularly in early phase of acantholysis. In Darier's disease and Hailey-Hailey's disease, dotted or rim-like patterns were already lost in early acantholysis and immunoreactive desmoglein I proteins were observed diffusely in the cytoplasm. Immunoelectron microscopy confirmed these immunofluorescence observations. It was suggested that in pemphigus vulgaris desmoglein I is unlikely to be the primary site of acantholysis because dotted or rim-like patterns of immunoreactive desmoglein I are relatively preserved on lesional cells, whereas in genodermatoses such as Darier's disease and Hailey-Hailey's disease primary abnormalities of desmosomes may be involved in their acantholysis.