Isolation and partial characterization of an elastase-type protease in human vulva fibroblasts: its possible involvement in vulvar elastic tissue destruction of patients with lichen sclerosus et atrophicus.

A complete disappearance of orcein positive material was observed in the superficial dermis of patients suffering from Lichen sclerosus et atrophicus. An elastase-type protease was isolated and partially purified from Triton X-100 extracts of human vulvar fibroblasts by gel permeation chromatography. It presents the characteristics of a metalloenzyme hydrolyzing Succinoyl-tri-alanine paranitroanilide maximally at pH 8.0 and is also active towards insoluble elastin. When partially purified enzyme is directly applied on to rabbit skin sections or when injected intradermally to young rabbits, it produces appreciable degradation of elastic fibers. The involvement of this protease in the disappearance of elastic fibers in Lichen sclerosus et atrophicus is postulated.