[Ammonium bituminosulfonate (Ichthyol). Anti-inflammatory effect and inhibition of the 5-lipoxygenase enzyme]. / Ammoniumbituminosulfonat (Ichthyol). Antientzündliche Wirkung und Hemmung des Enzyms 5-Lipoxygenase.

Ammonium bituminosulphonate (Ichthyol) inhibits 5-lipoxygenase activity in human polymorphonuclear neutrophils. The inhibition is dose-dependent and occurs at non-cytotoxic concentrations of the drug. This results in a decreased release of Leukotriene B4 from polymorphonuclear neutrophils. Furthermore, when applied to the ear skin of AB/Bln mice pretreated with croton oil, Ichthyol reduces the inflammatory reaction.

Inhibition of rat heart allograft rejection by a PUVA treatment of the graft recipient. Role of cisurocanic acid.

Treatment of rat heart grafts with PUVA, the combination of the photosensitizer 8-methoxypsoralen and longwave ultraviolet light, leads to a prolonged transplant survival in allogeneic recipients. A PUVA treatment of the recipient rats, performed for 7 consecutive days after transplantation, prolonged graft survival even more effectively. This may be due to the systemic immunomodulatory effects of PUVA in the recipient. One of the mediators is urocanic acid, which is transformed by ultraviolet light in the skin from its trans- to the cis-isomer, which, in turn, acts as a mediator on the immune system. An injection of cisurocanic acid into graft recipients for 7 consecutive days after transplantation resulted in prolonged graft survival; in 40% of the rats, permanent graft acceptance was observed. The significance of these results for clinical organ transplantation is discussed.

[The effect of Tomesa therapy on epidermal Langerhans cells in experimental animals]. / Die Wirkung der Tomesa-Therapie auf epidermale Langerhanszellen im Experiment.

In the last years a new therapy of psoriasis was developed, which consists in a treatment with salt solutions, resembling the water of the Dead Sea, and ultraviolet light (Tomesa-therapy). We studied the influence of the used salt on ATPase positive epidermal Langerhans cells in murine ear skin. An irreversible partial reduction of the Langerhans cell ATPase was found after salt treatment of separated epidermis or of full skin preparations. These results may have implications for the optimization and broader application of this therapy.

[Prolonging transplant survival time by PUVA treatment of the transplant recipient. Significance of cis-urocanic acid]. / Verlängerung der Transplantatüberlebenszeit durch eine PUVA-Behandlung des Transplantatempfängers. Bedeutung von cis-Urocaninsäure.

A PUVA treatment of the recipients of murine tail skin grafts led to a significant prolongation of transplant survival. A possible mechanism of the systemic immunomodulatory effects of ultraviolet light in the organism is the transformation of urocanic acid in the skin from its trans- to the cis-isomer, which acts as a mediator on the immune system. A treatment of graft recipients with cis-, but not trans-urocanic acid also prolonged graft survival. The rejection of secondary grafts and the humoral immune response of mice to sheep erythrocytes were not influenced by cis-urocanic acid. These results implicate that cis-urocanic acid may be get use in clinical organ transplantation and dermatology.

[Immunostimulants--therapeutic aspects]. / Immunostimulantien--Therapeutische Aspekte.

A survey is given about the so far known mode of action and the therapeutic application of the following agents with immunostimulatory effects: Interleukin-2, Interferon-gamma, Tumor necrosis factor, Thymosin alpha 1, Thymopentin, Splenopentin, Thymulin, Thymostimulin, Muramyl dipeptide, Bestatin, Tuftsin and Levamisole. The treatment of patients suffering from immunodeficiency disorders and cancer with such agents seems to be possible in the near future.

The effect of PUVA treatment on acid hydrolases in human polymorphonuclear leukocytes.

The activity of intracellular acid hydrolases in polymorphonuclear leukocytes (PMNL) from psoriatic patients and normal control subjects was determined. No significant differences between healthy and psoriatic individuals were detected, but a slight decrease in acid hydrolase activity was found in PMNL of psoriasis patients during PUVA therapy. PUVA treatment of PMNL in vitro at intensities that may be achieved in situ in the epidermis led to intracellular inactivation of acid hydrolases, which was not due to secretion of the enzymes or cell damage. The decrease in PMNL hydrolase activity appeared to be evoked by PUVA-generated reactive oxygen species because reduced glutathione prevented this decrease. The activity of free extracellular acid hydrolases was not affected by PUVA, and the superoxide production of PUVA-treated PMNL was increased. These results suggest that intracellular inactivation of acid hydrolases and possibly other lysosomal enzymes in PMNL or monocytes infiltrating the epidermis may contribute to the antipsoriatic activity of PUVA therapy.

Detection of interferon in the sera of patients with psoriasis, and its enhancement by PUVA treatment.

Interferon-like activity could be detected in the sera of nineteen psoriatic patients (interferon titres between 8 and 64 i.u./ml), whereas healthy controls were negative. Following PUVA treatment the interferon levels increased significantly (interferon titres between 32 and 128 i.u./ml). An enhanced interferon production could explain some of the immunological phenomena connected with PUVA treatment.