Lysosomal hydrolases of the epidermis.

Abstract
The activities of 14 acid hydrolases were measured in normal and diseased human epidermis. Increased hydrolase activity was common in lesions; the clinically uninvolved skin of patients, however, invariably showed normal values. The pattern of change was independent of the nature of the disease, the arylsulfatases and .beta.-glucosidase usually showing the greatest elevations. The magnitude of the changes differed from disease to disease, being most marked in the lesions of psoriasis. Ichthyosiform erythroderma was exceptional in showing elevated levels of the galactosidases and cathepsins B1 and D. (With the exception of ichthyosiform erythroderma) the observed abnormalities may be related to the proliferative rate of the epidermis.