Ralf Uwe Peter

Interleukin-8 receptor-mediated chemotaxis of normal human epidermal cells.

Normal human keratinocytes show chemotactic behavior towards interleukin‐8 (IL‐8). Under physiological conditions this cylokine seems to be present in an equilibrium between monomeric and dimeric forms, as indicated by Western blotting data. Radioligand binding studies suggest that keratinocyte chemotaxis is mediated by receptors specific for IL‐8 dimers. IL‐8 rcceptor‐specific mRNA can be detected in a keratinocyte cell line by polymerase chain reaction.

Mycophenolate mofetil: A new therapeutic option in the treatment of blistering autoimmune diseases

BACKGROUND Mycophenolate mofetil (MMF), an ester of mycophenolic acid (MPA), was approved by the Food and Drug Administration in 1995 and is currently primarily indicated for the prophylaxis of rejection in renal transplant patients. The drug seems also to be of value in the treatment of psoriasis and rheumatic arthritis. Recently there have been 6 reported cases of successful treatment of blistering autoimmune diseases with MMF in combination with high dose prednisone therapy. OBJECTIVE On the basis of these reports we administered this new treatment regimen to several patients with blistering autoimmune diseases. Besides using a combination of MMF and high-dose prednisone we wanted to evaluate whether MMF monotherapy is also effective in the treatment of blistering autoimmune diseases. METHODS We administered MMF to 5 patients who had severe pemphigus vulgaris or bullous pemphigoid. Two patients received MMF in combination with high-dose prednisone therapy and 3 patients received MMF monotherapy. To our knowledge, this is the first report of successful treatment of pemphigus vulgaris and bullous pemphigoid with MMF monotherapy. RESULTS All patients were completely free of symptoms within 8 to 11 weeks of therapy. Patients who had received MMF monotherapy responded as well to treatment as those who received a combination of MMF and high-dose prednisone. CONCLUSION Our experiences strongly suggest that MMF monotherapy may be effective for patients even with severe pemphigus vulgaris and bullous pemphigoid. In addition, MMF monotherapy, at least over the short term, offers the advantage of fewer side effects in comparison to immunosuppressive combination therapy and was well tolerated by our patients.

Chromosome Painting in Highly Irradiated Chernobyl Victims: A Follow-up Study to Evaluate the Stability of Symmetrical Translocations and the Influence of Clonal Aberrations for Retrospective Dose Estimation

Follow-up fluorescence in situ hybridization (FISH) measurements of symmetrical translocations were performed in peripheral blood lymphocytes from 12 highly irradiated victims of the Chernobyl nuclear power plant accident biannually, between September 1991 and July 1994, to investigate the persistence of these aberration type with time post-exposure. Translocations were determined using biotin-labelled painting DNA probes for human chromosomes 1, 4 and 12 and a digoxigenin-labelled alpha-satellite pancentromeric DNA probe. In 11 of 12 cases the translocation frequencies remained fairly constant during the observation period, which allows to generate comparable dose estimates on the various sampling times. In one case (no. 9) the existence of a cell clone containing the consistent chromosome rearrangement t(1;13) (q25;q14) was identified using FISH in rehybridized slides with a digoxigenin-labelled painting DNA probe for chromosome 13 and a separate G-banding analysis. To obtain reliable dose estimates, total translocation frequency has to be corrected for the high contribution (16.5-23.5%) of this clonal translocation.

Successful treatment and prophylaxis of scalp seborrhoeic dermatitis and dandruff with 2% ketoconazole shampoo: results of a multicentre, double‐blind, placebo‐controlled trial

Pityrosporum ovale appears to play an important role in the pathogenesis of seborrhoeic dermatitis. Ketoconazole is an antimycotic agent with a high in vitro and in vivo efficacy against P. ovale. We performed a multicentre study to investigate the efficacy of ketoconazole 2% shampoo in the treatment and prophylaxis of seborrhoeic dermatitis and dandruff. Five hundred and seventy‐five patients presenting with moderate to severe seborrhoeic dermatitis and dandruff of the scalp were treated with 2% ketoconazole shampoo twice weekly for 2–4 weeks, producing an excellent response in 88%. Of those patients who responded, 312 were included in a prophylactic phase, lasting 6 months. These patients were treated with the active preparation (shampoo containing 2% ketoconazole) once‐weekly, once every other week, alternating with placebo (shampoo without ketoconazole), or with placebo only once‐weekly. Forty‐eight (47%) patients in the placebo group experienced a relapse of seborrhoeic dermatitis, compared with 23 (19%) patients in the active treatment group, and 31 (31%) patients in the active/placebo group. The medication was well tolerated in all three groups.

Outdoor activities in childhood: a protective factor for cutaneous melanoma? Results of a case-control study in 271 matched pairs.

Background A matched case–control study was performed in Munich, Germany, in 1996–97 to evaluate the risk of cutaneous melanoma due to ultraviolet (UV) exposure behaviour in Southern Bavaria, Germany.

Phototherapy for atopic eczema with narrow-band UVB ☆ ☆☆

Management of atopic dermatitis has been less than satisfactory. Conventional therapy has not been particularly successful, and prolonged use of topical corticosteroids and systemic immunosuppressant drugs (eg, corticosteroids, cyclosporine, azathioprine) can result in severe cutaneous and systemic effects. We decided to evaluate the effect of UVB at 311 nm to treat 5 patients with moderate to severe atopic dermatitis. In each patient a mean cumulative dose of 9.2 J/cm2 was applied over a mean of 19 irradiations. Narrow-band UVB notably reduced atopic dermatitis after 3 weeks in all patients.

Dicentric and translocation analysis for retrospective dose estimation in humans exposed to ionising radiation during the Chernobyl nuclear power plant accident

Chromosome analyses were carried out in peripheral blood lymphocytes obtained between September 1991 and March 1992 from 15 persons exposed to ionising radiation during the Chernobyl nuclear power plant accident. At present, all are being treated for symptoms of the delayed stage of the cutaneous radiation syndrome. Biological dose-equivalent estimates were determined, either by measuring the frequency of dicentric and ring chromosomes in first division unstable cells from conventional preparations (Qdr method), or by measuring the frequency of stable translocations using two-colour fluorescence in situ hybridisation (FISH) with composite whole chromosome-specific DNA libraries for human chromosomes 1, 4 and 12 (chromosome painting) and a degenerate alpha-satellite pancentromeric DNA probe. With both methods fairly comparable individual estimates between 1.1 and 5.8 Gy were obtained for 12 of 15 individuals. Three individuals exhibited no elevated aberration frequencies. Perspectives and limitations of chromosome painting for dose reconstruction of past radiation exposures are discussed.

Increased Expression of the Epidermal Growth Factor Receptor in Human Epidermal Keratinocytes after Exposure to Ionizing Radiation

The effect of exposure of human epidermal keratinocytes to ionizing radiation, both in vivo and in vitro, on the expression of the epidermal growth factor receptor (EGF-R) was studied on the protein, mRNA, and functional levels. Quantitative fluorometry of short-term organ cultures incubated with a monoclonal antibody against human EGF-R revealed a dose-dependent increase of EGF-R expression 24 h after irradiation with 4 and 6 Gy, with an additional increase after 48 h. In biopsy specimens from patients undergoing radiation therapy a markedly increased expression could be determined by quantitative fluorometry during radiation therapy which wa still considerably above the baseline level 4 weeks after termination of treatment. Radioligand binding assays demonstrated a 50% increase in 125I-EGF binding to primary keratinocytes and A431 cells, at doses of 1 Gy, with a further increase after 72 and 96 h. Northern blots were performed with total RNA from two human epidermal cell lines (SCLII and A431). In A431 cells, increased EGF-R transcript levels could be detected 48 h after irradiation. In cells of the SCLII cell line, EGF-R expression was not affected by irradiation. These results were confirmed by semiquantitative polymerase chain reaction of primary cultured keratinocytes, demonstrating an increase of transcripts of EGF-R 24 h after irradiation with single doses of 6 Gy. Thus exposure to ionizing radiation leads to an increased expression of functionally intact EGF-R in human keratinocytes, at the protein and mRNA levels, both in vitro and in vivo; we hypothesize that this effect is part of a stress program of epidermal cells in response to ionizing radiation, ensuring rapid repopulation of irradiated areas.

Chronic sclerodermic graft-versus-host disease refractory to immunosuppressive treatment responds to UVA1 phototherapy☆☆☆

Graft-versus-host disease is a frequent complication of allogenic bone marrow transplantation. Approximately 10% of patients suffering from chronic graft-versus-host disease develop sclerodermic graft-versus-host disease of the skin, which often does not respond to conventional immunosuppressive therapy. An alternative to immunosuppressive treatment is photochemotherapy. We describe a patient with chronic sclerodermic graft-versus-host disease who did not respond to a combination therapy of cyclosporine and prednisone and later mycophenolate mofetil plus prednisone. A combination therapy of mycophenolate mofetil (2 g/day) and low-dose UVA(1) therapy (single dose, 20 J/cm(2), 4 times per week over 6 weeks) resulted in striking clinical improvement of sclerodermic graft-versus-host disease.

NF-κB and AP-1 are responsible for inducibility of the IL-6 promoter by ionizing radiation in HeLa cells

Purpose : To investigate the mechanisms leading to initiation by ionizing radiation of IL-6 transcription in HeLa cells. Materials and methods : HeLa cells were irradiated with X-rays at a dose rate of approximately 1 Gy/min or treated with TPA (100 ng/ml). Transient transfection analysis with truncated IL-6 promoter CAT constructs was used to identify the radiation-sensitive region within the IL-6 promoter/enhancer. Results : For basal expression of the IL-6 gene in unirradiated control cells the presence of the binding site for the nuclear factor kappa B (NF- κB) and the multiple response elements (MRE) were necessary. After deletion of either the activator protein (AP)-1 or the MRE site, radiation-induced IL-6 promoter CAT activity was significantly reduced, whereas after deletion of the NF-kappaB site it was completely abolished. Maximal radiation-induced IL-6 promoter CAT activity was observed when the AP1, NF κB and MRE motifs were present. In electrophoretic mobility shift analyses (EMSA), X-ray-inducible activity was found for NF-kappaB and AP-1 at the MRE constitutive, but no inducible activities were detectable. The nuclear factor IL-6 (NFIL6) element showed no specific radiation-responsive activity. Conclusions : These results demonstrate that NF- κB plays a major role in X-ray-inducible IL-6 expression in HeLa cells. The fact that IL-6 promoter activity was dramatically enhanced in the presence of the MRE and distal AP-1 binding motif is indicative of a cooperative mode of transcriptional activation involving all three transcription factor systems. These data provide new insights into the prodromal events of radiation-induced inflammation of epithelial cells and putatively the cutaneous radiation syndrome.PURPOSE To investigate the mechanisms leading to initiation by ionizing radiation of IL-6 transcription in HeLa cells. MATERIALS AND METHODS HeLa cells were irradiated with X-rays at a dose rate of approximately 1 Gy/min or treated with TPA (100 ng/ml). Transient transfection analysis with truncated IL-6 promoter CAT constructs was used to identify the radiation-sensitive region within the IL-6 promoter/enhancer. RESULTS For basal expression of the IL-6 gene in unirradiated control cells the presence of the binding site for the nuclear factor kappa B (NF-kappaB) and the multiple response elements (MRE) were necessary. After deletion of either the activator protein (AP)-1 or the MRE site, radiation-induced IL-6 promoter CAT activity was significantly reduced, whereas after deletion of the NF-kappaB site it was completely abolished. Maximal radiation-induced IL-6 promoter CAT activity was observed when the AP-1, NF-kappaB and MRE motifs were present. In electrophoretic mobility shift analyses (EMSA), X-ray-inducible activity was found for NF-kappaB and AP-1 at the MRE constitutive, but no inducible activities were detectable. The nuclear factor IL-6 (NF-IL6) element showed no specific radiation-responsive activity. CONCLUSIONS These results demonstrate that NF-kappaB plays a major role in X-ray-inducible IL-6 expression in HeLa cells. The fact that IL-6 promoter activity was dramatically enhanced in the presence of the MRE and distal AP-1 binding motif is indicative of a cooperative mode of transcriptional activation involving all three transcription factor systems. These data provide new insights into the prodromal events of radiation-induced inflammation of epithelial cells and putatively the cutaneous radiation syndrome.