G. Mahrle

Low-dose short-term cyclosporine versus etretinate in psoriasis: Improvement of skin, nail, and joint involvement

BACKGROUND High-dose cyclosporine therapy significantly alleviates psoriasis within 2 to 4 weeks but is associated with a high rate of side effects. Reports are conflicting on the frequency and promptness of relapse after discontinuation of cyclosporine therapy. OBJECTIVE Our purpose was to compare the efficacy and safety of low-dose cyclosporine with that of etretinate and the stability of remission after replacing cyclosporine therapy with topical anthralin during tapering of cyclosporine. METHODS In a multicenter study 210 patients with moderate to severe chronic plaque-type psoriasis were randomly assigned to treatment with cyclosporine or etretinate. The initial dosages were 2.5 mg/kg/day for cyclosporine and 0.5 mg/kg/day for etretinate, which could be individually adjusted to 5.0 and 0.75 mg/kg/day, respectively. After a treatment phase of 10 weeks (phase 1) patients receiving cyclosporine were again randomly assigned to a group in which cyclosporine was replaced by topical dithranol (anthralin), or to another group in which the drug was tapered during the next 12 weeks (phase 2). All patients treated with etretinate discontinued therapy after 10 weeks and used topical dithranol. RESULTS Mean Psoriasis Area and Severity Index decreased by 71% in the cyclosporine group and by 47% in the etretinate group during phase 1. After 10 weeks of treatment 47% of the patients treated with cyclosporine and 10% of those treated with etretinate showed a reduction of more than 80% in skin involvement. Sixty-four percent of the cyclosporine group and 48% of the etretinate group did not require an increase in the initial dosage, resulting in a mean daily dose of 3.0 and 0.53 mg/kg, respectively. There was significant alleviation of nail involvement and joint complaints in both groups. In phase 2 the increase in mean Psoriasis Area and Severity Index and the incidence of relapse were significantly higher in patients in whom cyclosporine was discontinued and replaced by dithranol than in patients in whom cyclosporine was tapered or who were pretreated with etretinate. During treatment four patients from the cyclosporine group and three patients of the etretinate group discontinued the study because of side effects. CONCLUSION Low-dose short-term cyclosporine therapy for psoriasis is, in comparison with etretinate, highly effective and well tolerated. Individually adjusted cyclosporine therapy allows the majority of patients to continue the low dosage of 2.5 mg/kg/day and still achieve a good clinical response. Remission can be better preserved by tapering the drug than by discontinuing treatment abruptly.

Cyclosporine in Severe Psoriasis

ObjectiveA meta-analysis of 3 major German studies conducted between 1989 and 1994 with cyclosporine in severe psoriasis was performed to allow an integrated evaluation of the efficacy and tolerability of cyclosporine in this indication.Design and SettingAll 3 studies were prospective, randomized, parallel group studies. The studies were conducted in 61 dermatologic centers in Germany.Patients and InterventionsThe studies involved 597 patients with severe plaque type psoriasis. Treatment consisted of cyclosporine (at a dosage of 1.25, 2.5 or 5 mg/kg/day), etretinate (at a mean daily dose of 0.53 mg/kg/day) or placebo in a total of 756 treatment cycles with a maximum duration of 12 weeks.Main outcome measures: The main outcome measures were the psoriasis area and severity index (PASI) andserum creatinine level.ResultsThe meta-analysis revealed that cyclosporine given in a dosage of 2.5 and 5 mg/kg/day was significantly superior to etretinate. In addition cyclosporine 1.25 mg/kg/day proved to be significantly more effective than placebo. An increase in serum creatinine level that required intervention occurred in 3.4% of cyclosporine treatment cycles.ConclusionCyclosporine is highly effective and well tolerated in the short term treatment of severe psoriasis.

Colorimetric growth assay for epidermal cell cultures by their crystal violet binding capacity

SummaryThe application of a simple, rapid, and inexpensive colorimetric growth assay was tested for human epidermal cells subcultured in uncoated plastic dishes. Cell layers were incubated with a crystal violet (CV) solution (0.2% with ethanol 2% in 0.5 M Tris-Cl buffer, pH 7.8) for 10 min at room temperature. After rinsing with 0.5 M Tris-Cl (pH 7.8) the cell layer was dried and decolorized with a sodium-dodecylsulfate solution (0.5% with ethanol 50% in 0.5 M Tris-Cl, pH 7.8) for 60 min at 37°C. The extinction of the supernatant was read at the absorption maximum of 586 nm. The protein content of attached cells as classical parameter for quantifying cell growth was strongly related to CV extinction with a correlation coefficient of r=0.98. Furthermore, the subcellular protein binding qualities of CV were analyzed. The water-soluble protein fraction of cultured epidermal cells was separated by sodium-dodecylsulfate polyacrylamide gel electrophoresis and stained with CV. We found a staining pattern which was qualitatively very similar to that of Coomassie blue, however less intense. Keratin electrophoresis revealed an affinity of CV to the 48, 50, and 56 kD cytokeratins. In conslusion, this CV assay is a reliable and simple method for the monitoring of epidermal cell growth in cultures.

Antiproliferative and cytotoxic profiles of antipsoriatic fumaric acid derivatives in keratinocyte cultures.

Oral administration with complex mixtures of fumaric acid derivatives is known to have antipsoriatic efficacy. The present studies aimed to clarify the mode of action and toxicity of the individual compounds. Hyperproliferative HaCaT keratinocytes in monolayer cultures were exposed to fumaric acid, dimethylfumarate, zinc monoethylfumarate, calcium monoethylfumarate and magnesium monoethylfumarate at concentrations between 0.4 microM and 960 microM for 48 h. Cell proliferation was studied by [3H]thymidine incorporation. In addition 14C-labelled amino acid uptake and total protein content were measured. Direct cytotoxicity was determined by the release of cytoplasmic lactate dehydrogenase (LDH) into the culture medium. The corresponding 50% inhibition concentrations (IC50) were calculated for DNA/protein synthesis: 2.3/2.5 microM (dimethylfumarate), 133/145 microM (zinc monoethylfumarate), 215/230 microM (calcium monoethylfumarate), 275/270 microM (magnesium monoethylfumarate), > 960/> 960 microM (fumaric acid). The total protein content was less sensitive. Antiproliferative activity was found for dimethylfumarate and to a lesser degree for calcium monoethylfumarate already at the subtoxic concentrations of 1.3 and 4 microM, respectively. In the case of magnesium monoethylfumarate, zinc monoethylfumarate and fumaric acid there was no such dissociation between their cytotoxic and antiproliferative potential. These data indicate that most of the antipsoriatic potential of fumaric therapies is due to the dimethylfumarate compound.

Anti‐inflammatory efficacy of low‐dose cyclosporin A in psoriatic arthritis. A prospective multicentre study

Summary Fifty‐five patients with psoriatic arthritis were treated with a low dose of cyclosporin A (CyA) (mean dose 2.7 mg/kg per day) for a period of 6 months to investigate the efficacy of CyA on disease parameters. Significant improvement in the joint complaints and inflammation parameters was observed including a decrease in the number of painful (‐46%) and swollen (‐45%) joints, tenderness (Ritchie Index: ‐50%) and degree of swelling (‐46%), patients assessment of pain (‐35%), the duration of morning joint stiffness (‐37%), as well as a decrease in C‐reactive protein (‐52%). A 50% reduction of joint complaints required a total of 24 weeks, whereas a 50% reduction of skin involvement was achieved after 5–6 weeks of treatment. Four patients left the study due to adverse events: creatinine level increase in two patients, hypertension in one patient and gastroenteritis in the fourth patient. Joint scintigraphy in 18 patients indicated an improvement or stable condition in 61% of cases after a mean follow‐up of approximately 8 months. The results of this prospective study show that low‐dose CyA effectively improves not only skin lesions, but also joint complaints in psoriatic arthritis.

Immunohistochemistry of porcine skin

The present paper reports immunohistological findings in porcine skin, which were obtained by use of mono- and polyclonal antihuman antibodies and either alkaline phosphatase anti-alkaline phosphatase (APAAP) or peroxidase (POX) technique. Epidermal staining was observed with antibodies to keratins (K 8.12, RSKE 60), filaggrin, and calmodulin (ACAM). Staining of connective tissue and vessels was achieved using antibodies to vimentin (V9(1)), collagen type IV, and fibronectin. In general, these antibodies gave a staining pattern similar to that of normal human skin. The similarities of immunoreactivity to poly- and monoclonal antihuman antibodies in porcine and human skin render porcine skin a reliable model in biomedical research.

Lactate dehydrogenase release as an indicator of dithranol-induced membrane injury in cultured human keratinocytes

SummaryHaCaT cells, a rapidly multiplying human keratinocyte line, were tested for their sensitivity to antipsoriatic dithranol with regard to classical proliferation parameters and for the drugs action on the plasma membrane integrity by the dose- and time-dependent release of cytosolic lactate dehydrogenase (LDH). In the case of 3H thymidine as well as 14C amino acid incorporation the 50% inhibition concentration (IC50) was 0.2 ΜM dithranol 24 h after initial exposure to the drug. For protein content of attached cells the IC50 proved to be>3.0 ΜM. Using 0.3, 1.0 and 3.0 ΜM dithranol, significant (p<0.05) dose dependent LDH release of 0.866±0.387, 1.842±1.127 and 2.938±1.635 mU per hour and cm2 confluent culture area was measured between the 5th and the 24th hour, compared to an acetone control of 0.504±0.299 mU/ h×cm2. Between the 2nd and the 4th hour as well as from the 25th to the 48th hour and the 49th to the 72nd hour the LDH release after dithranol treatment did not exceed the control value. In accordance with these findings dose-dependent morphological signs of cell injury were detected by phase contrast microscopy beyond the 4th hour. The data reveal that: HaCaT cells are a very sensitive target for the antiproliferative action of dithranol; the drug causes considerable plasma membrane damage even at concentrations as low as 0.3 ΜM; and this membrane damage becomes evident after a latency of at least 4 h and for a limited period of up to 24 h.

Effect of Fumaric Acid, Its Dimethylester, and Topical Antipsoriatic Drugs on Epidermal Differentiation in the Mouse Tail Model

Fumaric acid, fumaric acid dimethylester, and the dithranol derivative C4-lactone were studied in the mouse tail test to evaluate their effects on epidermal cell differentiation compared with other topical antipsoriatic drugs, such as betamethasone, calcipotriol, and dithranol. Mouse tails were treated for 2 weeks and longitudinal histological sections prepared of the tail skin. The length of the orthokeratotic regions (stratum granulosum) was measured on 10 sequential scales per tail and expressed as percentage of the full length of the scale. In addition, epidermal thickness was measured and the efficacy of the various compounds evaluated. In comparison to 2% salicylic acid ointment, all tested compounds except fumaric acid significantly (p < or = 0.05) increased the proportion of the orthokeratotic region. C4-lactone and calcipotriol were less effective than dithranol, fumaric acid dimethylester only moderately influenced cell differentiation, and betamethasone showed the least potent effect. Dithranol was the most potent substance inducing orthokeratosis without increasing epidermal thickness.

IL-1 alpha-induced expression of ICAM-1 on cultured hyperproliferative keratinocytes: suppression by antipsoriatic dimethyl-fumarate.

Background. In the psoriatic plaque both IL‐1 dysregulation and ICAM‐1 expression on keratinocytes have been previously described. Furthermore systemic administration of fumarates has been reported to be effective in psoriasis. We, therefore, studied the effect of dimethyl‐fumarate ester (DMF) on the putative IL‐1‐induced ICAM‐1 expression.

Immunohistochemical and immunoelectron microscopic demonstration of chromogranin A in formalin-fixed tissue of Merkel cell carcinoma

BACKGROUND Chromogranin A (CGA) is the major protein of neurosecretory granules (NSG) of cells of the diffuse neuroendocrine system, and the amount of CGA corresponds to the number of NSGs. OBJECTIVE Because formalin fixation may destroy NSGs, a study was performed to examine the presence of CGA in Merkel cell carcinoma (MCC) to determine whether CGA depends on the presence of intact NSGs. METHODS Formalin-fixed, paraffin-embedded tissue of 15 MCCs was investigated by immunohistochemistry and immunoelectron microscopy for the presence of CGA and NSGs. RESULTS CGA was demonstrated in 12 of 15 MCCs by immunochemistry and in 6 of 10 MCCs by immunoelectron microscopy although intact NSGs could not be discerned in all cases. CONCLUSION CGA remains demonstrable even when no morphologically intact NSGs are present, which suggests that CGA is not exclusively responsible for the electron density of NSGs.