B. Knopf

Immunhistochemical localization of calmodulin in normal and psoriatic epidermis

Calmodulin (CAM) is a major Ca2+-binding intracellular protein of eukaryotic cells. As well as having other functions, it has been related to proliferation, cell cycle, differentiation, and spatial arrangement of intermediate filaments (for overview see [2]). CaM gained particular attention in psoriasis research with publication of the first report on raised activity in psoriatic plaques, by van de Kerkhof and van Erp in 1983 [1, 3, 7 9 , 11]. Nevertheless, no information is available about the intraepidermal distribution of this protein in psoriatic skin. As far as we know, there is only one recent report of immunohistochemical CaM detection on paraffin sections of normal human skin, suggesting a homogeneous distribution in all living cell layers [5]. Therefore, using histochemical techniques, we investigated epidermal CaM in normal and psoriatic skin. Skin biopsy specimens were obtained from healthy volunteers, and lesional and nonlesional psoriatic skin from patients after local analgesia. The tissues were snapfrozen in liquid nitrogen and processed to unfixed frozen sections of 4-1am thickness. Potyclonal anti-CaM was raised in rabbits, as previously described [10]. The working dilution was 1 : 100 in phosphate-buffered saline (PBS), pH 7.4, supplemented with 0.2% bovine serum albumin and 0.5 ml Tween 20 per liter. Tissue sections were treated with PBS-Tween 20 containing 5% goat serum for 20 min at room temperature and washed twice. Anti-CaM was added

Distribution of glycoconjugates in human skin apperdages

The purpose of this paper is to describe the occurrence and distribution of glycoconjugates in normal human epidermis and skin appendages (pilosebaceous unit, eccrine sweat gland) by means of FITC-labelled lectins (ConA, WGA, UEA I). Both the outer hair root and the follicular ostium-epithel disclosed a glycoconjugate expression with close homology to interfollicular epidermis. The acinar epithelium of sebaceous glands and the inner layers of hair follicles showed a more or less distinct staining pattern. Lectin binding of eccrine sweat glands revealed marked differences between ducts and secretory coils. The epithelial distribution of glycoconjugates indicates a relatively independent differentiation pathway of eccrine sweat glands compared with other specialized epithelia of the human skin.

PUVA treatment of human cultured fibroblasts from psoriatic skin enhances the binding of antibodies to SSA(Ro)

The expression of nuclear antigens seems to be cellcycle related [5, 7]. Some of them can be detected by autoantibodies usually found in sera from patients with systemic lupus erythematosus. In psoriatics, antinuclear antibodies (ANA) might become detectable during treatment with psoralens and ultraviolet A (320-400 mm), commonly referred to by the acronym PUVA [1, 4, 8, 17]. Other reports failed to show ANA induction by antipsoriatic PUVA regimes [13]. Recently, Kulick et al. [10] proposed that the presence of antibodies to SSA(Ro) is a serologic marker for patients with a lupus erythematosus/psoriasis overlap. Since PUVA treatment of cultured fibroblasts is able to induce DNA strand breaks [2] and inhibits their growth [5], this might be followed by an altered reactivity to ANA or vice versa in a modified autoantigen expression. The present paper reports our attempt to study the in vitro effects of PUVA on the binding of a panel of autoantibodies usually detectable in lupus erythematosus sera, e.g., on (nuclear) autoantigen expression. Skin biopsies were taken from untreated psoriatics. Fibroblasts were cultured in Mfiller tubes using the following medium: MEM (Staatliches Institut ffir Immunpr/iparate und N/ihrmedien, Berlin, GDR; SIFIN) 1.08 g L(+)-glutamine 60mg, streptomycin 100~tg/ml, penicillin 100IU/ml in 100 ml aqua bidest. Twenty percent fetal calf serum (SIFIN) was added. For harvesting cells, the culture was treated with trypsin 0.2% (Difco, Michigan, USA) chelaplex-III 0.02% (VEB Berlin Chemie,

Immunolocalization of cytokeratins in human eccrine sweat glands

Eccrine sweat glands of adult human skin were described in terms of immunohistological distribution of cytokeratins using monoclonal antibodies. The results are in favour of a segmental cytokeratin expression and provide a feasible basis for the investigation of pathological conditions.

Increase of epidermal calmodulin precedes the formation of a psoriatic lesion

Calmodulin (CAM) is an important calcium-binding polypeptide strongly associated with proliferation, cell-cycle phase, and cell-to-cell coupling [1, 5, 7, 8]. Its possible impact on dermatology has been reviewed recently [12]. Since the first report about grossly elevated CaM levels in psoriatic lesions was published [11] epidermal CaM has gained particular interest in research on psoriasis. Although most investigators agree that CaM levels of psoriatic lesions are elevated twoto threefold (expressed as gg CaM per mg soluble epidermal protein) [2, 4, 6, 11, 13], both the specificity for psoriasis as well as the time sequence of CaM increase and the development of a clinical lesion have been questioned [4, 10l. The purpose of our study was to investigate the psoriasis specificity of elevated CaM in epidermal lesions. Additionally, we attempted to investigate the relationship between CaM and the formation of psoriatic lesions. Skin biopsy specimens were obtained of healthy skin (n = 9), untreated psoriatic lesions (n = I0), perilesional skin of spreading psoriatic lesions within 1 cm of the palpable border of the plaque (n = 6), and nonlesional psoriatic skin (n = 4), as well as from seborrheic keratosis (n = 5), lichen tuber planus (n = 3), balanoposthitis (n = 1), pityriasis rubra pilaris (n = 1), and bullous pemphigoid (n = 1). Biopsy specimens were frozen quickly in liquid nitrogen. Dermis and epidermis were dissected. The latter was homogenized with an all-glass hand homogenizer using the following buffer (pH 7.2): 50 m M Tris-HC1,

Topical interferon-alpha in psoriasis increases epidermal calmodulin activity.

Evidence is accumulating that interferons (IFNs) are involved in psoriasis pathogenesis [8]. Both the antiproliferative and immunomodulatory activities that IFNs exert may also be useful in psoriasis therapy [7-10]. IFNalpha was shown to provide antiproliferative activity on cultured human keratinocytes [10]. Since the antiproliferative effects of different antipsoriatic drugs have been connected with their calmodulin (CAM) antagonism in vitro [1], it was our aim to investigate calmodulin activity and IFN-alpha. Five patients with stable plaque-like psoriasis and no history of antipsoriatic treatment during the previous 2 weeks participated in the study after giving informed consent: four men and one woman, aged 3 5 7 5 years (mean _+ SD, 50 + 16 years). Three lesions located on the upper legs, with a duration of less 4 weeks, and that were compareable in size, localization, and clinical score for scaling, erythema, and infiltration (score 0, no symptoms; 1, slight; 2, moderate; 3, strong)were selected for topical IFN-alpha therapy. IFN-alpha was kindly donated by the Central Institute of Microbiology and Experimental Therapy of the Academy of Sciences of the GDR, Jena. The recombinant IFN-alphal was produced in E. coli with a purity above 99%. For topical use a solution containing 1.2 x 10 v IU IFN-alpha~ in 30 m M citrate/NaOH (pH 5.1) supplemented with 10% (v/v) Gelafusal was employed. In part (a) of the experiment, one lesion per patient was treated with a single application of IFN. Punch biopsy specimens were taken after 12 h and 48 h. In part (b) of the experiment the second lesion of each patient was treated once daily with IFN for 3 5 days and a punch biopsy specimen was taken at the end of treatment. In part (c) of the experiment, the third lesion of each patient was treated once daily with the IFN-free solution

FITC-insulin binding to normal and psoriatic epidermis.

FITC-insulin was prepared and applied to frozen human skin sections. In normal and nonlesional psoriatic epidermis, the binding was cytoplasmic in suprabasal cells. In psoriatic lesions, fairly stained or even unstained cells were littered in suprabasal epidermis indicating the expansion of selected basal cell qualities into the stratum spinosum.