Lack of effect of oral selenite on p53 associated gene expression during TL01 therapy of psoriasis patients

Selenium (Se) has protective properties against ultraviolet (UV)-induced changes in skin cells in vitro but little is known about such activity in human subjects. In the present study, seven patients with psoriasis ingested 400 microg of sodium selenite daily during a 4 week course of whole-body narrow-band UVB (TL01) therapy while six more psoriasis patients, similarly irradiated, ingested a placebo. Skin biopsies, collected at the start and end of the phototherapy were analysed for phosphorylated p53, Fas, Bcl-2, Bax and oxidized guaninosine, and for numbers of Langerhans and sunburn cells. Following the TL01 therapy, no significant difference was observed for any of these markers when the Se group was compared with the placebo group of patients, although p53 and Bcl-2 expression decreased in the Se supplemented group.     

The effect of ultra violet B (TL-01) phototherapy on epidermal expression of p53 protein in psoriatic plaques

BACKGROUND: Psoriasis is a genetically determined inflammatory skin disease. It is now recognized that narrow band TL-01 phototherapy is an effective treatment for psoriasis. However, ultraviolet (UV) exposure induces p53 mutations in keratinocytes and repeated exposure of skin to UV radiation results in clonal expansion of these initiated p53-mutant cells within the epidermis. AIM: The present study aims to examine epidermal p53 expression in the skin of psoriatic patients at different time points following TL-01 phototherapy. METHODS: Skin samples from patients suffering from plaque-type psoriasis, collected before, during and at the final stages of TL-01 phototherapy were examined for p53 expression by immunohistochemistry. RESULTS/CONCLUSION: Our results showed an increase in p53 expressing keratinocytes following TL-01 phototherapy. Some of these cells were arranged spatially, as conical clones arising from putative stem cell compartments, suggesting that the chronic TL-01 treatment might have triggered cell growth and clonal expansion, an important step in initiating skin carcinogenesis.     

Ultraviolet-B phototherapy is successful in Japanese patients with early-stage mycosis fungoides

UVB phototherapy is widely used for the treatment of psoriasis and atopic dermatitis, however, only limited reports evaluate its usefulness in the treatment of mycosis fungoides. We introduced UVB phototherapy to five patients with early-stage mycosis fungoides. All of them were classified as stage IB (erythematous stage), and none had obtained a satisfactory response to other therapies. After initial treatment with UVB phototherapy, all the patients obtained significant improvement in their skin lesions leaving pigmentary changes. After this satisfactory response was achieved, the same dose of UVB was administrated as a maintenance therapy with longer intervals between exposures. Histopathological examination of three patients revealed decreased numbers of inflammatory cells in both the epidermis and the dermis after the treatment. Immunohistochemical study showed that CD1a+/HLA-DR+ dendritic cells were present throughout the lesional epidermis before the treatment. In contrast, after the treatment, the dendritic cells in the epidermis were CD1a+/HLA-DR-. Although it remains unclear why only the expression of HLA-DR antigen was eliminated after treatment, we presume that this loss of HLA-DR antigen expression by epidermal Langerhans cells was, in part, responsible for the improvement of skin lesions. This preliminary study suggests that UVB phototherapy is an effective treatment for patients with early-stage mycosis fungoides.     

银屑病患者T细胞对表皮c-myc、bcl-2及p53蛋白表达影响的实验研究

目的 探讨银屑病患者T细胞促发表皮动力学改变的机制.方法将皮肤组织与银屑病患者外周血T细胞混合培养,免疫组化法检测培养前、培养后第3天、第6天表皮c-myc bcl-2及p53表达.结果未培养的银屑病患者皮损c-myc及p53表达增强,bcl-2表达减弱;银屑病正常皮肤表达无明显改变.银屑病正常皮肤及正常人皮肤分别与银屑病T细胞共培养后第3天,p53表达显著增强,共培养第6天后,c-myc表达显著增强,bcl-2表达显著降低,且银屑病正常皮肤与正常人皮肤受银屑病T细胞作用后二者间差异无显著性.结论c-myc、bcl-2及p53的异常表达与银屑病皮损表皮动力学紊乱密切相关;银屑病T细胞可影响表皮c-myc、bcl-2及p53的表达,从而影响表皮的增殖状态;银屑病发病的关键可能在于T细胞的异常,而不是表皮角质形成细胞。     

Narrow-band UVB phototherapy (Philips TL01 lamps) in psoriasis]

The authors report the results of an open study conducted on 53 patients with psoriasis treated by narrow-band UVB phototherapy, using Philips' TL01 lamp. With a simple procedure which did not require MED determination this treatment gave satisfactory results in 92 p. 100 of the cases, with mild burns in only 9 p. 100. The morphological type of psoriasis (patchy, guttate or nummular) had no influence on the therapeutic result, but the degree of infiltration of the lesions and their location on the lower limbs proved to be a factor of relative resistance. In most patients the results were obtained in 20 sessions with a mean cumulative dose of 20.19 +/- 2.7 J/cm2. Some patients had an additional treatment of 6 sessions. The results obtained with Philips' TL01 lamp were as satisfactory as those obtained with the conventional UVB lamps, but the TL01 lamp seemed to be easier to handle and better tolerated, which gives them some advantages over the latter.     

Premature keratinocyte death and expression of marker proteins of apoptosis in human skin after UVB exposure

Epidermal keratinocytes undergo a process of terminal differentiation or cornification that in many aspects resembles apoptosis. It is characterized by the elimination of cell nuclei within the granular layer, whereas the cytoplasm is transformed into horn cells. Premature death of keratinocytes can be induced by extrinsic factors such as UV irradiation. We investigated the time-dependent expression of apoptotic marker proteins in the skin of one healthy human volunteer after irradiation with a fourfold minimal erythema dose (MED) of UVB. The data were supplemented by including healthy skin areas of biopsies from patients UVB-irradiated for therapeutic reasons. Punch biopsies were analysed by in situ end-labelling (ISEL) for DNA strand breaks and by immunohistochemistry for expression of p53, bcl-2, active caspase-3 and its proform, and deoxyribonuclease I (DNase I). Keratinocytes with pyknotic nuclei were first detected 6 h after UVB exposure, and apoptotic keratinocytes (sunburn cells) 12 h after exposure. These aggregated to sunburn bodies after 24 h. In control skin, nuclei with DNA strand breaks were only occasionally detected in the granular layer but 6 h after UVB irradiation in the spinous layer. After 12 h, many sunburn cells were ISEL-positive and positively stained for active caspase-3, P53, and DNase I. Morphometric evaluation of the immunohistochemical data demonstrated that maximal upregulation of P53, DNase I and activation of caspase-3 occurred 12 h after irradiation and in advance of the peak of apoptotic cell death reached after 24 h as verified by ISEL. In contrast, strong Bcl-2 immunostaining appeared restricted to presumed melanocytes and basal cells but was not increased after UVB irradiation.     

p53蛋白在UVB诱导凋亡的富集表皮干细胞的角质形成细胞中的表达

目的研究p53蛋白在中波紫外线(ultraviolet lightB,UVB)诱导凋亡的富集表皮干细胞的角质形成细胞群中的表达情况。方法分离富集人表皮干细胞的角质形成细胞群和正常角质形成细胞群,使用UVB诱导两种细胞群凋亡,蛋白印迹法比较不同剂量UVB诱导前后两组细胞的p53蛋白表达的差异。结果两种细胞在不同剂量的UVB照射后p53蛋白表达均比照射前显著增加,在20mJ/cm2与40mJ/cm2照射剂量时,富集人表皮干细胞的角质形成细胞群p53蛋白表达高于正常角质形成的细胞群,差异有统计学意义(P<0.05)。结论富集人表皮干细胞的角质形成细胞p53蛋白表达比其它角质形成细胞对中波紫外线的照射易感。     

Effect of continued ultraviolet B phototherapy on the duration of remission of psoriasis: a randomized study

Phototherapy using sunburn spectrum ultraviolet radiation (UVB) is now a frequently utilized treatment for psoriasis that is extensive or has not responded to topical preparations. Four university centers performed a prospective randomized clinical trial to compare remission times of patients with psoriasis who continued UVB phototherapy after initial clearing with this therapy and patients whose UVB phototherapy was discontinued within 3 weeks of clearing. As assessed by life table methods, the time to flare after initial clearing for patients on UVB maintenance therapy was significantly longer than for patients who discontinued UVB within 3 weeks after initial clearing. Our data suggest that continuing UVB phototherapy after initial clearing contributes to the duration of disease control and is justified for many patients.     

No evidence for increased skin cancer risk in psoriasis patients treated with broadband or narrowband UVB phototherapy: a first retrospective study

Phototherapy of skin diseases such as psoriasis is an effective and safe treatment modality. However, increasing the risk of skin cancer by phototherapy is a serious concern. An increased skin cancer risk occurs after prolonged photochemotherapy (PUVA). In contrast, the role of broadband UVB or narrowband UVB therapy in skin carcinogenesis of humans with psoriasis is less clear. Therefore, we investigated the incidence of skin tumours in a total of 195 psoriasis patients, receiving broadband (n=69) or narrowband (n=126) UVB from 1994 to 2000 with follow-up until 2003. Data were raised from the regional interdisciplinary cancer centre of the University of Tuebingen, Germany and compared with the tumour incidences given for the German population. In this study, with 80% statistical power to detect a 6-7-fold increase in skin cancer with broadband UVB and 83% power to detect a 5-6-fold increase with narrow band UVB at p=0.05, only one patient developed skin cancer - an in situ melanoma. The tumour occurred within the same year that phototherapy was initiated. Thus, the present study does not provide evidence for an increased skin cancer risk for patients treated with either broadband or narrowband UVB phototherapy     

结合珠蛋白在银屑病皮损及皮损周边外观正常皮肤中的表达

目的 从mRNA及蛋白质水平研究结合珠蛋白在银屑病皮损及皮损周边外观正常皮肤中的表达,探讨其与朗格汉斯细胞的关系及在银屑病发病中的作用.方法采用免疫组化、免疫荧光双标记和原位杂交技术检测银屑病皮损及皮损周边外观正常皮肤中结合珠蛋白的表达.结果与正常人皮肤相比,银屑病皮损处角质形成细胞中结合珠蛋白mRNA的表达均明显增强(P＜0.001);皮损周边外观正常皮肤中的表达与正常人皮肤差异无显著性(P＞0.05).免疫组化显示:皮损处部分角质形成细胞胞浆中有结合珠蛋白表达;皮损及皮损周边外观正常皮肤中均可见结合珠蛋白在部分朗格汉斯细胞中呈阳性表达,且两者中结合珠蛋白阳性朗格汉斯细胞与朗格汉斯细胞总计数的比值较正常皮肤显著增高(P＜0.001).结论银屑病皮损处角质形成细胞中结合珠蛋白mRNA的表达增强,并能合成结合珠蛋白.合成结合珠蛋白的角质形成细胞可能在银屑病发病机理中起负反馈调节作用。     

Evaluation of vaseline oil applied prior to UVB TL01 phototherapy in the treatment of psoriasis

BACKGROUND: Use of emollient prior to phototherapy could enhance UV transmission through psoriasis plaques on the condition that the emollient is not photoprotective. Emollient pretreatment with narrow-band phototherapy (313 nm) has not been studied extensively. We conducted a study to assess if vaseline oil prior to UVB TL01, in chronic psoriasis plaques could accelerate psoriasis clearance. METHODS: Fifteen patients with chronic psoriasis plaques were enrolled in a prospective, single-blind, controlled study. For each patient, one to three symmetrical pairs of plaque were selected and scored initially and after every six exposures. RESULTS: On the vaseline oil pretreated side, significantly more plaques were cleared, especially in severe psoriasis. Scaling and infiltration were significantly improved. Application of vaseline oil was more interesting in thick and scaly psoriasis probably because the oil penetrates the intercellular space allowing an optical matching effect which increases the UV transmission. CONCLUSION: We strongly recommend vaseline oil pretreatment with UVB TL01 phototherapy in psoriasis, especially in severe psoriasis.     

Lymphocytes and macrophages of the epidermis and dermis in lesional psoriatic skin,but not epidermal Langerhans cells,are depleted by treatment with cyclosporin A

Summary Since cyclosporin A (CsA) is an immuno-suppressive agent, its beneficial effect in psoriasis suggests that immune cells may play a role in the pathogenesis and resolution of psoriasis. To determine early effects of CsA in psoriasis, we quantitated immune cells using double immunofluorescence microscopy on biopsy specimens obtained prior to therapy and after 3,7, and 14 days of CsA therapy. CsA therapy resulted in significant reductions in the absolute number of immune cells (including T cells, monocytes/macrophages, and antigen presenting cells) contained within psoriatic skin. The effect was rapid, with over one-half of the reduction in the density of HLe1⁺ (human leukocyte antigen-1 positive or bone marrow derived) cells, including T cells, activated T cells, monocytes, and Langerhans cells (LCs), occurring within 3 days. Despite the overall reduction in the numbers of immunocytes in the skin, the proportion of T cells, Langerhans cells, and monocytes in relation to the total number of immune cells was unchanged with therapy, reflecting equally proportional losses of each subtype. Dermal CD1⁺DR⁺ cells (putative Langerhans cells), which are not found in normal skin but are present in lesional psoriasis skin, were virtually cleared from the papillary dermis after CsA therapy. Although absolute numbers of epidermal Langerhans cells, defined as cells expressing both CD1 (T6) and DR molecules (CD1⁺DR⁺), were also reduced after CsA, epidermal non-Langerhans CD1^-DR⁺ cells (macrophages, activated T cells, DR^- keratinocytes) demonstrated a proportionally greater decrease, with the ratio of CD1⁺DR⁺ Langerhans cells/non-Langerhans CD1^-DR⁺ epidermal cells changing from a mean of 0.82 at baseline to 1.92 at day 14. Thus, early in the course of therapy, CsA appears to be effective at clearing CD1^-DR⁺ cells while leaving LC relatively intact in the epidermis.This work was supported in part by the Babcock Foundation     

Narrowband–UVB irradiation decreases the production of pro-inflammatory cytokines by stimulated T cells

Narrow-band ultraviolet B (UVB) phototherapy is an effective treatment for psoriasis. Owing to its limited penetration, the direct effects of UVB are mostly restricted to cells residing in the epidermis and papillary dermis, and are associated with epidermal depletion of Langerhans’ cells (LC) and T cells. It has been argued that the depletion of the skin-resident T-cell population may be due to a combination of UVB-induced apoptosis and decreased recruitment from the blood due to lower expression of the required adhesion and homing molecules. We have previously demonstrated that UVB treatment can alter the expression of adhesion molecules by blood lymphocytes, and as these can be influenced by cytokines, the aim of this study was to investigate whether UVB irradiation can also influence the cytokine production of circulating T cells. Four patients with active chronic plaque psoriasis were treated daily with narrow-band 312 nm UVB irradiation and blood samples obtained before treatment and weekly thereafter for 2 weeks. Peripheral blood mononuclear cells (PBMCs) were isolated and cultured with a streptococcal superantigen or a conventional streptococcal antigen preparation, and cell culture supernatants were assayed for various cytokines. When stimulated with the superantigen, PBMCs from UVB-treated psoriasis patients secreted greater amounts of the anti-inflammatory cytokine IL-10, and showed markedly decreased production of IL-1β, IL-2, IL-5 and IL-6 compared to the pre-treatment values; the production of IFN-γ, IL-8 and IL-12p70 were also decreased but did not reach statistical significance. Thus, the combination of UVB-induced apoptosis, increased secretion of anti-inflammatory cytokines and decreased trafficking to the skin may help to explain the beneficial effects of UVB treatment on psoriasis and why disease remission can sometimes be sustained for a prolonged period.     

An open-label study of alefacept plus ultraviolet B light as combination therapy for chronic plaque psoriasis

BACKGROUND: Alefacept, a fully human LFA-3/IgG(1) fusion protein, is a selective biological agent approved in the United States for the treatment of chronic plaque psoriasis. In phase 3 trials, clinical improvement and prolonged off-treatment remission of psoriasis correlated with reductions in circulating memory T cells. Reductions in pathogenic epidermal T cells in psoriatic lesions also have been noted following phototherapy with ultraviolet B (UVB) light. Because alefacept and UVB target T cells in different ways, combination therapy with these two agents may lead to greater efficacy. OBJECTIVES: To determine the safety, tolerability, and efficacy trends of combination therapy with alefacept plus UVB light in patients with chronic plaque psoriasis. METHODS: In an open-label, parallel-group study conducted at two sites, one in France and one in the United States, patients with chronic plaque psoriasis who were candidates for phototherapy received 12-weekly intramuscular injections of alefacept, 15 mg. In addition, patients were randomized to one of three treatment arms: no UVB treatment, 6-week UVB treatment, and 12-week UVB treatment. UVB treatment consisted of narrowband (NB) UVB at the site in France and broadband (BB) UVB at the site in the United States. The 12-week treatment period was followed by a 12-week follow-up period. Clinic visits occurred weekly during treatment and every 2-4 weeks during follow-up. RESULTS: A total of 60 patients (n = 30/site) were enrolled in the study. Alefacept was well tolerated when administered in combination with UVB treatment and as monotherapy. There was no evidence of increased phototoxicity or photosensitivity with the combination. At each study site, alefacept/UVB provided a higher overall response rate and led to a more rapid onset of response compared with alefacept monotherapy. Of patients who achieved > or = 50% reduction from baseline Psoriasis Area Severity Index (PASI 50) at 2 weeks after the last dose of alefacept, 75-100% in the combination therapy groups maintained this response throughout follow-up in the absence of further psoriasis therapy. CONCLUSIONS: In patients with chronic plaque psoriasis, combination therapy with alefacept plus short-term (6-12 weeks) UVB treatment is well tolerated with a trend toward greater and more rapid efficacy than alefacept alone.     

Mechanisms of cyclosporine A inhibition of antigen-presenting activity in uninvolved and lesional psoriatic epidermis

To elucidate how cyclosporine A affects antigen-presenting cell subsets and their function in human skin, we studied patients with psoriasis undergoing a therapeutic trial of cyclosporine A. Immunologic parameters abnormal in psoriatic epidermis were evaluated before and early in the course of therapy. We quantitated function and numbers of skin biopsy-derived epidermal cells with potential antigen-presenting cell (APC) activity. The antigen-presenting capacity of epidermal cells from normal-appearing skin to activate allogeneic T cells was profoundly inhibited (81% decrease) 7 d after the onset of therapy (p less than 0.05). Thus, cyclosporine A therapy inhibited T-cell activation mediated by Langerhans cells in uninvolved skin. By contrast, in lesional skin epidermal allo-antigen presenting activity was only partially inhibited at this early time point (55 +/- 7% decrease) (p less than 0.01, n = 8). The percentage decrease in allo-antigen-presenting cell activity correlated with reduced clinical activity of the lesions, r = 0.84. In three patients also examined at 14 d, we found an additional 42 +/- 5% decrease between day 7 and 14. Decreased allo-antigen-presenting activity in lesional skin was not associated with a decrease in the number of CD1+ Langerhans cells or epidermal cell release of detectable amounts of cyclosporine A or other soluble factors that abrogate T-cell alloreactivity. The time course and degree of inhibition of antigen-presenting capacity within involved psoriatic skin correlated best with a significant (p less than 0.01) reduction in non-Langerhans cell DR+ leukocytes (from 3.0 +/- 1.2% to 1.0 +/- 0.6% at day 7) (r = 0.71). Cyclosporine A therapy was associated with a rapid and complete loss of HLe1-DR+ keratinocytes (94% decrease at 7 d) in lesional skin despite the skin still being quite involved with psoriasis at this point and antigen-presenting cell activity being only 60% reduced. In conclusion, cyclosporine A interferes with T-cell activation by human epidermis through at least two mechanisms: 1) in uninvolved skin, rapid inhibition of Langerhans cell-mediated activation of T cells, and 2) in lesional skin, delayed inhibition of antigen-presenting activity which appears to correlate with the time course and level of reductions in non-Langerhans cell DR+ leukocytes. The antigen-presenting activity of the latter cells appears to be cyclosporine A resistant. In psoriatic lesions, early and complete loss of DR expression on lesional keratinocytes during cyclosporine A therapy is likely due to decreased lesional T-cell lymphokine production critical for keratinocyte DR expression.(ABSTRACT TRUNCATED AT 400 WORDS)     

系统性红斑狼疮患者CD1a、CD68、HLA-DR等的研究

目的 研究系统性红斑狼疮(SLE)患者外观正常及病变皮肤中朗格汉斯细胞(LC)一些重要表面标志的变化。方法 应用CD1a、CD68和HLA-DR等单克隆抗体和ABC免疫组化技术对9例SLE患者外观正常和皮损部位的组织进行了免疫表型检测。结果 ①SLE皮损中LC的数量减少,且其形态与表面标志亦有变化;②SLE病损处的角质形成细胞(KC)强弱不等地表达HLA-DR抗原,个别病例的外观正常皮肤KC也可局灶性表达HLA-DR抗原;③SLE外观正常皮肤或皮损的表皮中均未见细胞间粘附分子1和CD4阳性LC,仅在真皮的浸润细胞中见到较多的阳性细胞;④发现在SLE外观正常皮肤和皮损表皮内出现两类CD68阳性的树枝状细胞;在SLE皮损的浸润细胞中CD68阳性树枝状细胞大量增加;⑤细纤维状CD68阳性物质呈网状围绕基底部的KC,这些细纤维状阳性物质有些与表皮树枝状细胞相连,有些则没有明显的关系。结论 SLE外观正常和病变皮肤中LC一些重要表面标志的变化有所不同。外观正常皮肤和皮损表皮内出现两类树枝状细胞,一类可能为LC,而另一类则来源不清;在SLE皮损的浸润细胞中这些CD68阳性树枝状细胞大量增加,表皮内存在CD68阳性纤维状染色,其意义尚需进一步研究。     

Photoadaptation to ultraviolet (UV) radiation in vivo: photoproducts in epidermal cells following UVB therapy for psoriasis

BACKGROUND: Ultraviolet (UV) radiation is mutagenic and induces specific DNA lesions in human skin that are often found at dipyrimidine sites. These photoproducts are likely to be biologically relevant regarding skin carcinogenesis, as p53 mutations in skin tumours are most often found at these UV radiation-specific sites within DNA. Psoriasis patients receiving long-term phototherapy are at an increased risk of non-melanoma skin cancers. OBJECTIVES: The aim of this study was to quantify DNA photoproducts in human epidermis in vivo following consecutive doses of UVB and to investigate variations in DNA damage according to skin type, UVB dose and age. METHODS: Eleven psoriasis patients receiving UVB phototherapy three times a week were recruited and underwent skin biopsies on a non-sun-exposed site before starting phototherapy and after three, nine and 18 UVB exposures. A biopsy was also taken at least 4 weeks after stopping phototherapy. DNA was extracted from separated epidermis and three types of photoproducts were quantified using a novel 32P high-performance liquid chromatographic technique. RESULTS: The mean level of cyclobutane dipyrimidine dimers (CPDs) after three doses of UVB (dose range 0.03-0.15 J cm-2) was 3.2 (range 0.8-8.9) photoproducts per 106 normal nucleotides for TT=T dimers and 4.5 (range 0-14) per 106 normal nucleotides for TT=C dimers. The mean levels of TT-C 6-4 photoproducts after three doses of UVB were very low (0.2, range 0-1.8). Overall, the levels of TT=T and TT=C reached a plateau at three exposures and were found to decrease for subsequent exposures despite increasing UVB doses. Skin type was negatively associated with mean levels of CPDs. However, significant differences in levels of photoproducts were seen between individuals, even after adjusting for skin type. No association was found between challenge dose of UVB and photoproduct yield in this study. CONCLUSIONS: This study showed a great individual variation in the accumulation of DNA photoproducts following exposure to repetitive doses of UVB. Photoadaptive responses of human skin involving DNA repair, tanning and epidermal thickening are likely to explain the overall lack of increase in DNA lesions throughout phototherapy. This in vivo study confirms that psoriasis patients produce a significant amount of DNA photolesions at suberythemal doses of UVB. Further work is needed to investigate which host factors are most likely to predict susceptibility to UV radiation-induced DNA damage.     

窄谱中波紫外线治疗前后银屑病皮损中CD1a^＋DC、Ki-67的表达

目的探讨窄谱中波紫外线（NB—UVB）治疗对银屑病患者皮损中CD1a^＋树突细胞（CD1a^＋DC）及Ki-67水平的影响。方法采用免疫组化法分析寻常性银屑病患者NB—UVB治疗前后皮损中及非皮损中CD1a^＋DC及Ki-67的表达。采用银屑病皮损面积和严重性指数（PASI）进行病情严重程度评分。结果27例银屑病患者中,治疗前皮损中CD1a^＋DC及Ki-67表达水平（15±4;53±12）高于非皮损（9±3;22±6）及治疗后患者皮损的表达量（9±3;25±1）（P〈0．05）。银屑病皮损的严重程度PASI评分与Ki-67表达相关（r=0．29,P〈0．05）。银屑病皮损的严重程度PASI评分与CD1a抗原的表达量之间无相关性（r=-0．27,P〉0．05）。结论NB—UVB可以通过调节皮肤免疫系统达到治疗目的。银屑病患者皮损中Ki-67表达水平与银屑病皮损的严重程度PASI评分有关。     

银屑病表皮热休克蛋白27、70、60的表达

目的：探讨热休克蛋白（HSP）在银屑病发病中的作用。方法：通过免疫组化和图像分析检测了25例银屑病患者治疗前后皮损、非皮损区表皮组织中HSP27、HSP70和HSP60的表达，并与6例正常人作对照。结果：HSP27、HSP70在非皮损、正常人表皮中呈基础表达，在银屑病患者皮损中的表达很弱，治愈后表皮后HSP27、HSP70的表达又恢复；HSP60的表达在银屑病皮损组表皮中均为阳性，而银屑病非皮损组、治愈后组表皮中及正常人对照表皮组织中HSP60的表达均阴性。结论：热休克蛋白在银屑病应激保护机制中可能发挥一定的作用。     

Monochromatic excimer light (308 nm): an immunohistochemical study of cutaneous T cells and apoptosis-related molecules in psoriasis

BACKGROUND: Various types of UVB radiation source (290-320 nm) are used in treating psoriasis and their therapeutic mechanism has been attributed to immunosuppressive properties. Recently, a new UVB source generated by a 308-nm excimer laser has been introduced for the treatment of psoriasis. OBJECTIVE: In this study we investigated the immunohistochemical evaluation of T cells and the expression of various apoptosis-related molecules in the psoriatic hyperproliferative skin before and after treatment with 308-nm monochromatic excimer light (MEL). METHODS: Ten patients (three women and seven men), ranging in age from 29 to 79 years, affected by plaque-type psoriasis vulgaris, were treated with MEL. Biopsies from psoriatic lesions of MEL-treated sites were taken before, 24 h and/or 48 h after the first irradiation and analysed by the immunophosphatase alkaline technique (APAAP). RESULTS: MEL treatment was found to cause a significant decrease in the rate of proliferation of keratinocytes and a relevant depletion of T cells in all psoriatic lesions, 48 h after the first irradiation: 308 nm light eliminated T cells from the psoriatic epidermis and also from the dermis, highlighting the ability of this UVB source to penetrate the skin compared with normal UVB and establish direct cytotoxic action on T cells infiltrating skin lesions. Rapid clearing of psoriatic lesions involves potential molecular targets of UVB in T cells including p53, which is upregulated after direct irradiation with 308-nm UVB. Moreover, Bcl-2 expression in healing psoriasis epidermis after MEL treatment is significantly decreased compared with untreated skin and the TUNEL (TdT-mediated dUTP-biotin nick end labelling) technique revealed the presence of relevant apoptotic keratinocytes in the irradiated epidermis. CONCLUSIONS: These results indicate that psoriatic skin after monochromatic excimer light therapy is associated with significant T-cell depletion and alterations of apoptosis-related molecules accompanied by a decreased proliferation index and clinical remission.