The duration of Grenz ray-induced suppression of allergic contact dermatitis and its correlation with the density of Langerhans cells in human epidermis

Recent investigations have shown that Grenz rays can suppress the allergic contact dermatitis reaction completely and that Langerhans cells, identified by OKT6 antibodies and electron microscopy, disappear from the epidermis at the same time. It is not known for how long this suppression lasts. This has been investigated in 28 nickel-sensitive patients who were given Grenz rays (3 Gy) on the back, once a week for 3 weeks. The patients were then divided into four groups and tested with patch tests for nickel at 1, 7, 14 and 21 days after the last Grenz ray treatment. Biopsies were taken from positive patch test sites, and from the corresponding opposite control. They were labelled with OKT6 antibodies to detect Langerhans cells. The patch test reactions were suppressed and the Langerhans cell density was decreased initially. These changes were restored after 3 and 6 weeks, respectively. The results show that the effect of Grenz rays on eczematous reactions extends to a maximum of 3 weeks and imply that Langerhans cells are necessary for the elicitation of the efferent phase of allergic contact dermatitis.     

Grenz ray therapy

Grenz rays (ultrasoft X-rays, Bucky rays) have been used in the treatment of benign skin disorders for more than 60 years. The mechanism of action, the clinical effect and the potential carcinogenic effect have remained largely unknown, and many of the reported studies are now obsolete. Recent studies of both the clinical and the basic characteristics of grenz rays have shown that the number of Langerhans' cells decreases in the human epidermis after treatment and that grenz rays can suppress the expression of nickel allergy in sensitive individuals. Also, very good results have been reported in the treatment of psoriasis of the scalp. A large-scale study involving more than 14,000 patients has shown that grenz ray therapy cannot be excluded as a risk factor in the development of non-melanoma skin tumors, but this risk factor is small and can virtually be disregarded when certain therapy recommendations are followed. This article is an attempt to summarize the present knowledge of grenz ray therapy.     

Lymphocytes and Langerhans cells in patch tests

The distribution of immunocompetent cells was analysed in allergic (nickel) and irritant (dithranol) patch tests using conventional transmission electron microscopy and labelling with monoclonal antibodies in an avidin-biotin immunoperoxidase study. The biopsies were taken 24 or 48 h after the allergen/irritant application. In allergic and irritant reactions, most inflammatory cells were OKT11 positive (pan T lymphocytes). The majority of these cells were also OKT4 positive (helper/inducer T lymphocytes), while the minority were OKT8 positive (suppressor/cytotoxic T lymphocytes). NK9 positive cells (natural killer cells) were observed in small numbers. The number of dendritic OKT6 and OKIal positive cells (Langerhans cells) in the epidermis was unaffected in allergic reactions. In irritant reactions, a normal number of OKT6 positive Langerhans cells was observed, while the number of OKIal positive cells had increased in the epidermis. Dithranol caused prominent fine structural changes in the mitochondria of the Langerhans cells, while the keratinocytes appeared largely unaffected. The present study indicates that allergic and irritant patch tests cannot be differentiated reliably using current immunohistopathological or electron microscopic techniques, in spite of the small differences observed.     

Lymphocyte subsets and Langerhans cells in allergic and irritant patch test reactions: histometric studies

This study has attempted to distinguish between allergic and irritant reactions to patch tests by semiquantitative histological methods. The extent of perivascular chronic inflammatory infiltrate at 72 h in irritant patch test reactions to sodium lauryl sulphate was shown to be small and very consistent, whereas in allergic reactions to nickel sulphate it was generally larger and more variable in size (p less than 0.02). The two major lymphocyte subsets (T4 and T8) were randomly intermixed in both types of reaction and formed the major component of both the perivascular and diffuse dermal infiltrate, without any evidence of selective migration. The T4:T8 ratios were similar in focal and diffuse infiltrates. The number of T6 dendritic (putative Langerhans) cells in the epidermis (per mm inner epidermal length) was usually greatly reduced in irritant reactions (5-16 mm-1, mean 10 mm-1) but remained within normal limits in allergic reactions (6-33 mm-1, mean 21 mm-1) (p less than 0.001). Comparable results were seen with other irritants (mercuric chloride and benzalkonium chloride) and other allergens (neomycin sulphate, ethylene diamine and potassium dichromate). In additional experiments, pairs of biopsies were taken from the reaction and from adjacent unaffected skin. The T6 cell density in the epidermis did not significantly differ between allergic reactions and control skin. By contrast, the irritant reactions had fewer T6 cells than the control skin (p less than 0.001).     

ETAF/Interleukin-1 and epidermal lymphocyte chemotactic factor in epidermis overlying an irritant patch test

We have previously demonstrated that the epidermal content of the lymphocyte activating peptide ETAF/IL-1 and lymphocyte chemotactic factor (ELCF) increases during the development of a cell-mediated immune reaction, represented either by the tuberculin skin reaction or by a positive patch test in patients with contact allergy. The present study describes the epidermal content of these mediators during an irritant patch test reaction. The results show that ELCF, but not ETAF/IL-1, is significantly increased in the epidermis of an irritant patch test with 3% SLS or 5% croton oil, irrespective of the intensity of the clinical patch test reaction. We observed that simple occlusion of epidermis did not induce ELCF activity in healthy persons, whereas patients with previous or current eczema had a significant release of ELCF following such occlusion. These results seem to indicate that there exist important functional differences between allergic and irritant patch test reactions with respect to the presence of lymphocyte activating signals in epidermis.     

Artificial disruption of skin barrier prior to irritant patch testing does not improve test design

BACKGROUND: Irritant patch testing is often performed as a 24- or 48-h occlusive patch test with low concentrations of sodium lauryl sulphate (SLS). OBJECTIVES: The aim of this study was to investigate potential ways to shorten this test procedure and obtain precise test results. PATIENTS AND METHODS: Thirty-six healthy volunteers underwent irritant patch testing with different pretreatments (PT) of the test fields. Occlusive test chambers were applied on the upper back with SLS 0.5%, 1%, 2% and 5% in large Finn Chambers(R). The patches were removed after 4 and 24 h, respectively, depending on the concentration used. Test fields were pretreated as follows: PT 0, field without any PT (control); PT 1, prick with lancet; PT 2, prick with test stamp; PT 3, scratch with lancet; PT 4, incision with standardized incision instrument (0.1-0.2 mm depth). Skin reactions were evaluated by transepidermal water loss (TEWL), skin erythema and skin hydration and as well by a visual score (VS) at 4, 24 and 72 h. RESULTS: Our data show an obvious distinction between PT 0-2 and PT 3-4 at all measurement methods. The average TEWL values with PT 3-4 were higher than those with PT 0-2, especially on the 4-h course. This distinction may derive from the shape and size of the skin impairment achieved by PT 3-4, leading to a mechanical barrier disruption. However, SLS may infiltrate directly into deeper skin layers supported by capillarity. Consequently, no or little penetration through the epidermis and interaction with its structures occurs, which is responsible for irritant skin reactions. The SLS dose in the upper skin layers is therefore lower at these PTs. The lower remaining dose of SLS also explains this distinction, especially for the VS. Additionally, there are presumed reactions in deeper layers of the epidermis and dermis at PT 3-4. CONCLUSIONS: In summary, all data suggest a different reaction pattern from the classical irritant response. Therefore, application without any PT seems to be best suited for irritancy skin testing, especially for visual assessment. PTs prior to irritant patch testing have been shown to be unjustifiable.     

The effect of grenz ray therapy on pustulosis palmoplantaris. A double-blind bilateral trial

The effect of grenz ray therapy in the treatment of pustulosis palmoplantaris was assessed in 15 patients by randomly allocating active treatment of the lesions of one side of the body, while the lesions on the other side, which received stimulated therapy, served as a control. Four Gy of grenz rays 10 kV were applied on 6 occasions at intervals of 1 week. A significantly better therapeutic result was recorded on the lesions which had received active grenz ray therapy. However, the therapeutic response was moderate. It is concluded that grenz ray therapy could be useful in pustulosis palmoplantaris mainly as an adjunct to other therapies.     

Psoriasis of the nails treated with grenz rays: a double-blind bilateral trial

The effect of grenz ray therapy in the treatment of psoriatic nails was assessed in 22 patients by randomly allocating active treatment to the psoriatic nails of one hand while the other one, which received simulated therapy, served as a control. Five Gy of grenz rays were applied on 10 occasions at intervals of 1 week. There was a significantly better response to active treatment compared with the untreated control. However, the therapeutic response was moderate. It is concluded that grenz ray therapy could be useful only when the psoriatic nails are of normal thickness.     

Influence of grenz rays and psychological factors on experimental pruritus induced by histamine and compound 48/80

Summary The interaction between grenz rays and experimentally induced pruritus was evaluated in 14 healthy subjects. Grenz rays were administered once weekly for 4 weeks on restricted areas of the upper arms. Pruritus was evoked by intradermal injection of histamine and the histamine liberator compound 48/80. The results were compared with unconditioned values and with those obtained following a placebo treatment procedure. The influence of psychosocial and psychosomatic factors was also evaluated. Grenz-ray therapy reduced itch but not flare responses. The influence of grenz rays was, however, not statistically different from that observed after placebo treatment. Psychosocial and psychosomatic factors were good predictors of individual skin responsiveness. The results indicate that grenz rays do not interfere with experimental histamine-induced pruritus more than placebo and emphasize the importance of knowing individual characteristics and coping strategies.     

Additional effect of grenz rays on psoriasis lesions of the scalp treated with topical corticosteroids

In a double-blind study comprising 17 patients with symmetrical psoriasis lesions of the scalp, the combination of grenz ray treatment and topical steroid showed a faster clearing than with the topical steroid alone. The results also indicate a longer remission time with the combination therapy compared to grenz rays alone. Therefore both the faster clearing and the longer remission time with the combination therapy, as compared to our previous study of grenz ray treatment of scalp psoriasis, are probably due to the additional effect of steroid therapy, on grenz rays.     

Phenotypic difference between allergic and irritant patch test reactions in man

Cellular responses in allergic and irritant contact dermatitis were analysed in situ using an immunohistochemical double staining technique with the aim of uncovering phenotypical differences of diagnostic importance. Allergic and irritant patch test reactions were elicited in 9 individuals using the Finn chamber technique. Thirty-nine skin biopsies from these reactions and from petrolatum controls were obtained 4 to 20 days after the test applications. Cell infiltrates were present throughout the observation period in both allergic and irritant reactions, but were usually greater in the former. In both types of reaction, anti-Leu 3a reactive cells predominated over anti-Leu 2a reactive cells. HLA-DR expression on keratinocytes was found in 9 of 14 allergic reactions, but not in irritant reactions or control areas. HLA-DQ antigens were not detected on keratinocytes. The presence of HLA-DR antigens on keratinocytes may reflect an immunological response of the allergic reactions, and thus be of diagnostic relevance.     

Dynamic changes in the epidermal OKT6 positive cells at mild irritant reactions in human skin

In the present study we induced mild irritant contact reactions by using 0.5% sodium lauryl sulphate (SLS) in distilled water or with distilled water in patch tests for 6 or 24 hours. The biopsies were taken at 6, 24, 48 and 96 hours. Light and electron microscopy were used to assess the irritant reactions produced and the monoclonal antibody OKT6 was used for the detection of the LCs. The number of the epidermal OKT6 positive dendritic cells was found to be increased at 48 and 96 hours after the exposure to SLS and at 96 hours in the water patch tests. It is concluded that mild irritant stimuli cause an increase in the LCs (OKT6 positive cells) and thus might influence and modulate the response to subsequent exposures to allergens.     

Non melanoma skin cancer of the scalp. On the etiology

In order to evaluate the relative significance of previous grenz-ray treatment for human non melanoma skin carcinogenesis, the files were studied of all patients treated for non melanoma skin cancer of the scalp (n = 82, male/female ratio 1.1) at the Department of Dermatology, the Finsen Institute, from 1976 to 1985. Fourteen patients, with a male/female ratio of 3.7, were treated for squamous cell cancer (SCC). Sixty-five patients, with a male/female ratio of 0.9, were treated for basal cell cancer (BCC). Twelve patients (15%, 11 with BCCs, 1 SCC), of which eight with psoriasis, were previously treated with grenz rays on the scalp, and two of them had not been exposed to additional skin carcinogens. Comparably, malignant conversion in sebaceous and verrucous nevi accounted for 9 cases or 11%. Characteristically, scalp cancers associated with previous grenz-ray treatment were BCCs, the male/female ratio were less than 0.1 and two-thirds occurred in patients with multiple skin cancer. That grenz-ray related scalp cancers more often develop in females than in males was further confirmed by comparison to the sex distribution among patients treated on the scalp with grenz rays in the years 1950, 1960 and 1970 (p less than 0.01). (Accepted August 10, 1988.)     

Alterations of epidermal lectin binding sites in acute contact dermatitis

We investigated alterations of epidermal lectin binding sites, as well as of pemphigus and bullous pemphigoid antigens, in 28 human patch test reactions, both allergic (nickel, formaldehyde, N,N'-1,3-dimethylbutyl-N'-phenylenediamine) and irritant (sodium lauryl sulfate). The epidermal reactivity to a panel of lectins and human antisera to pemphigus vulgaris and bullous pemphigoid antigens was compared with samples obtained from normal skin and from skin under tape occlusion. We observed selective perturbations of lectin and antibody binding in acute contact dermatitis, whether allergic or irritant. The main findings were a loss of terminal sialic acids and longer bi- and triantennary mannosyl residues as well as a loss of pemphigus vulgaris antigen. The only difference between allergic and irritant patch test reactions was in topography of loss of WGA binding sites: in the former, it was most pronounced in the lower and middle epidermis, whereas in the latter it was seen in the uppermost subcorneal layers. Our findings support a common pathway of cell membrane alterations of keratinocytes in acute contact dermatitis.     

紫外线、补骨脂素加长波紫外线、境界线对皮肤接触过敏的影响

DNCB致敏豚鼠.分成3组,于背部一侧剃毛后皮肤分别应用治疗剂量UVR,GR照射、PUVA疗法,每周2-3次.共调.然后,于照射处和对称部位的非照射处皮肤进行DNCB激发试验和切取皮肤作Laagerhans细胞检查.结果表明:3种物理因子均可抑制DNCB引起的皮肤接触过敏反应.与此同时,Langerhans细胞的数量亦明显减少,试验的结果进一步证明皮肤接触过敏的发病与Langerhans细胞密切有关.同时提示了UVR,PUPA和GR可用于接触性过敏性皮炎的治疗.     

Treatment of cutaneous T-cell lymphomas (CTCL) with extracorporeal photochemotherapy--preliminary report

Since August of 1988, we have treated seven CTCL patients with extracorporeal photochemotherapy, including two with tumor-stage mycosis fungoides (MF) showing mucinous degeneration, two with plaque-stage MF, and two with erythrodermatous MF. One was withdrawn just after the first trial. For each patient, the phenotypes of peripheral blood lymphocytes were analyzed by flow cytometry in terms of the percentages of OKT11, OKT3, OKT4, Leu9, OKT8, B1, Tac, OKT9, OKIa1, Leu7, Leu3a/4B4, and Leu3a/2H4 cells. These parameters were compared with the clinical responses according to skin score. The two patients with tumors died, but the five patients without tumors did not. Three of the 6 patients responded to the treatment. Side effects that are often associated with standard chemotherapy, such as bone marrow suppression, gastrointestinal symptoms and hair loss, were not observed. One cardiovascular event (1 patient) occurred. No significant changes in T-cell subsets were seen during the course of therapy. These preliminary data suggest that extracorporeal photochemotherapy may be effective for CTCL other than tumor-stage MF.     

Thermographic assessment of patch-test responses

Infra-red thermography was used to quantify, at patch test sites, the allergic responses to experimental preparations of nickel sulphate and primary irritant responses to sodium lauryl sulphate in small groups of volunteers. The technique was also used to assess the patch-test responses in a much larger group of patients who had undergone routine patch testing for contact allergy with a wide range of test substances and among which there were large numbers of allergic, irritant and equivocal reactions. Thermographically, when compared to the surrounding normal skin surface, the sites of allergic reactions appeared as hot areas, the temperature and area of which were apparently dependent on the severity of the response. For allergic responses, there was a good correlation between the clinical assessment and either of two thermographic parameters, temperature and area of involvement. Compared with an aqueous solution of nickel sulphate, 'poor' formulations of the allergen, such as a suspension in soft paraffin base, elicited smaller and cooler reactions. Irritant reaction sites were not 'hot' and the temperature at such sites was no different from that of the surrounding normal skin. Infra-red thermography is a convenient non-invasive technique which apparently can be used to discriminate between irritant and allergic responses and to quantify the latter type of response.     

Epidermis and lymphocyte interactions during an allergic patch test reaction. Increased activity of ETAF/IL-1, epidermal derived lymphocyte chemotactic factor and mixed skin lymphocyte reactivity in persons with type IV allergy

Recently, we have found an increased activity of epidermal-derived thymocyte-activating factor (ETAF/IL-1) and epidermal lymphocyte chemotactic factor (ELCF) in epidermis overlying a positive tuberculin skin reaction. In the present study, we investigated 20 patients with confirmed or suspected allergic contact dermatitis by using the suction blister technique before and during patch testing. The ETAF/IL-1 was found in epidermis before patch testing. Its presence increased 2.8-fold in epidermis overlying a positive patch test compared with pretesting values. This increase was statistically significant. Interestingly, nontested skin also showed a significant increase of ETAF/IL-1, which was 1.9-fold higher than pretest values. The ETAF/IL-1 activity in patch test areas was significantly correlated with the clinical response. ELCF is not present in epidermis from noneczematous persons. We observed a significant content of ELCF in three of seven patients with eczema prior to patch testing. After patch testing, all patients showed ELCF in epidermis. Nontested skin showed a 1.5-fold higher content of ELCF compared with pretest values, and in the test area ELCF was 1.8-fold higher. The increases were statistically significant. We performed mixed skin lymphocyte reactions in seven patients using epidermal cells from the patch test area. All patients with a positive patch test had an increased mixed skin lymphocyte reactivity compared with epidermis coming from a negative reaction.