An examination of the levels of human B-glucuronidase in a Vohwinkel's Syndrome Patient, by Monica L. Nanosky-Hughes.

Abstract

Vohwinkel's Syndrome is a rare autosomal dominant epidermolytic palmoplantar keratoderma (EPPK). In 1995, Peris et al described as: 1.) diffuse hyperkeratosis of the palms of the hands and the soles ofthe feet in which the skin takes on a "honey-comb" appearance. 2.) "star-fish" shaped keratotic plaques on the dorsal surface of the hands and feet, the wrists, knees, and elbows. 3.) fibrous constricting bands (pseudoainhum) at the interphalangeal joints that may eventually lead to autoamputation of that digit. 4.) the invariable appearance of the disease early in life. 5. )and familial incidence (autosomal dominant inheritance pattern). Recently, it was discovered that one of the factors contributing to the disease was a molecular defect in a single protein located in the cornified cell envelope protein, termed loricrin (Mastrini, 1996).This defect seemingly impairs the differentiation process of the epidermal renewal system, by not allowing dead skin to slough off. The defect also contributes to barrier function impairment, causing affected patients to retain water in the keratinocytes. It was noted in 1988 by Camisa et al that Vohwinkel's Syndrome patients had an increased level in serum l3-glucuronidase. l3-glucuronidase is a lysosomal enzyme known to break down constitutive basement membrane proteins. It has been found in keratinocytes and Langerhan's cells. This study examined the levels of 13glucuronidase in epidermal skin punch biopsies, blood serum samples, and urine specimens from both diseased and non-diseased patients. A quantification of the levels of the enzyme was performed via a double antibody sandwich ELISA. It was hypothesized by this study that perhaps the increased levels of l3-glucuronidase was compensatory for the molecular defect in loricrin.