Ultrastructural studies of keratinized epithelia of the mouse. IV. Quantitative studies of lysosomes.

Electron microscope cytochemical and simple morphometric studies have permitted an estimate to be made of the absolute numbers of lysosomes present in various cell layers of murine epidermis. Most lysosomes appear to be present in basal layer keratinocytes with few being detected in Langerhans cells or in granular layer keratinocytes. The observation that lysosomes are not numerous in any of the strata is discussed with respect to an alternative explanation for the presence of diffuse acid hydrolase activity in the granular layers.