Tissue culture of epidermal cells in some acantholytic dermatoses

Cell adhesion in Hailey-Hailey disease and Darier's disease: immunocytological and explant-tissue-culture studies

The pathogenesis of Hailey-Hailey disease and Darier's disease was investigated using immunocytological and explant-tissue-culture techniques. There was breakdown of the intercellular adhesions between keratinocytes in explants from clinically uninvolved skin of patients with Hailey-Hailey disease or Darier's disease. The major desmosomal components were present in the cultures and were expressed in a punctate peripheral pattern at cell-cell contact sites, but there was diffuse staining of acantholytic cells. Plasminogen, which is expressed by basal keratinocytes in normal skin, was detected in association with suprabasal acantholytic cells in skin biopsies from these diseases. Plasminogen was reversibly displaced from the cells by 6-aminohexanoic acid, suggesting that binding is mediated by a reaction with the lysine receptor on the plasminogen molecule. Plasminogen was also detected in separating cells in explant cultures and there was cytoplasmic expression of the plasminogen activator urokinase by these cells. These abnormalities are not unique to either disease and do not account for the phenotypic differences between Darier's disease and Hailey-Hailey disease, but plasmin generation may have a role in perpetuating cell separation.

Darier's disease: an immunohistochemical study using monoclonal antibodies to human cytokeratins

The pathogenesis of Darier's disease was investigated by immunohistochemical staining of skin biopsies from involved and uninvolved skin in 14 patients, using monoclonal antibodies specific for keratins expressed in simple epithelia, stratified squamous epithelia and during skin specific differentiation as well as keratins expressed in mucosa and some benign epidermal hyperproliferative states. Uninvolved perilesional skin from Darier's patients showed a normal profile of keratin expression, whereas in lesional skin there was apparent delay in the expression of the suprabasal skin specific keratins. Suprabasal keratins were not detected in basal cells, thus there was no true premature keratinization. The presence of hyperproliferative keratins was restricted to suprabasal cells in lesional skin. Four patients were receiving treatment with etretinate at the time of biopsy, but results in these patients did not differ from patients using topical treatments. Etretinate did not influence the profile of keratin expression in uninvolved or involved skin. The expression of type VII collagen was examined and was normal throughout uninvolved and lesional skin in Darier's disease.

Surface ultrastructure of cultures of affected psoriatic keratinocytes, unaffected psoriatic keratinocytes and normal keratinocytes

The surface structure of 11-12 days old cultures from biopsies of normal skin and uninvolved psoriatic skin was investigated by scanning electron microscopy. The keratinocytes formed flat, thin, and well-organized layers of elongated, tightly apposed cells. Newly-formed cells with few and short microplicae and microvilli were seen at the colony periphery. On the maturing cells towards the colony center, the number and size of microplicae or microvilli increased gradually. No differences were found between the structures on normal keratinocytes and keratinocytes from uninvolved psoriatic skin, but in keratinocytes from involved psoriatic skin glomerulus-like rolled microplicae occasionally were found.