Cathepsin D expression in chronic plaque psoriasis: an immunohistochemical study.

Cathepsins are lysosomal cysteine proteases, which are involved in a variety of physiologic processes such as proenzyme activation, antigen presentation, tissue remodeling, bone matrix resorption, and pathologic processes such as facilitating tumor invasion and modulating the process of programmed cell death. This study aimed to evaluate the pattern of cathepsin D (CD) expression in chronic plaque psoriasis in comparison to normal skin by means of immunohistochemistry. The study included 34 patients presenting with chronic plaque psoriasis and 10 age- and sex-matched normal subjects as control group.