The fine structure of epithelial cells in normal and pathological buccal mucosa. II. Colloid body formation.

Seven cases of the erosive type of lichen planus, as well as normal tissue, were studied with the optical and electron microscope. The study was concerned with the distribution and formation of colloid bodies. These bodies were located at the epithelial-proprial junctions and occasionally inter-epithelially. They were seldom larger than basal epithelial cells and were macrophages which contained fragments of phagocytosed epithelial cells. They probably correspond to cytoid bodies which have a similar size and a similar distribution.