The role of factor XLLLa-positive dermal dendrocytes in HIV-1-positive psoriatics

Factor XLLLa-positive dermal dendrocytes (FXIIIa⁺ dd) may have an important role in the pathogenesis of psoriasis, in that their numhers are increased in lesional skin compared with non-lesionai skin. Moreover, in AIDS-associated Kaposi's sarcoma the number of these cells is also increased, in comparison with the classical type of Kaposi's sarcoma. In addition, patients suffering from HIV-1 infection may develop severe psoriasis. The aim of this study was to examine the distribution of FXIIIa⁺ dd in lesional and non-lesional skin from seven psoriatic patients with positive HIV-1 serology. and compare the results with age-, sex-, and site-matched HIV-1-negative psoriatic patients. In both patient groups there was an increase of FXIIIa ⁺dd in the papillary dermis in lesional skin, compared with non-lesional skin (HIV⁺ [P=0.0007]: HIV^? [P=0.0006]). Positive cells were also observed within the epidermis in lesional skin in both groups. However, there was no significant difference between HIV-1⁺ and HIV-1^? groups in the number of FXIIIa⁺ dd in the epidermis and dermis (P>0.05). These findings suggest that, if FXIIIa⁺ dd do have a role in psoriasis, deterioration of this condition in HIV-1⁺ patients is not due to proliferation of dermal dendrocytes.     

Interleukin-8 immunoreactivity in the skin of healthy subjects and patients with palmoplantar pustulosis and psoriasis.

Previous studies have shown that neutrophil-activating peptide 1/interleukin-8 (IL-8) is present in psoriatic scales and to a lesser extent in normal human epidermis. A panel of monoclonal antibodies and polyclonal antisera raised against IL-8 was used to localize IL-8 with immunoperoxidase techniques in non-lesional and lesional skin of patients with psoriasis and palmo-plantar pustulosis (PPP), and in corresponding sites from healthy subjects. Intracellular IL-8 immunoreactivity was found in all epidermal cell layers in biopsies of healthy subjects and in non-lesional and lesional skin in both PPP and psoriasis. The most intense immunolabeling was regularly found in the basal cell layer. Intercellular epidermal IL-8 immunolabeling was regularly detected in lesional biopsies in PPP and psoriasis, but not in healthy subjects or non-lesional skin in PPP and psoriasis. No intercellular immunolabeling was detected after successful treatment of lesional skin. The majority of cells along the eccrine sweat glands, dermal mononuclear cell infiltrates, and endothelial cells were IL-8 immunoreactive in all biopsies studied. The present study suggests that IL-8, its precursor form, or, alternatively, a degradation product is present in normal human epidermis.     

Correlation between macroscopic fluorescence and protoporphyrin IX content in psoriasis and actinic keratosis following application of aminolevulinic acid

In fluorescence diagnosis with 5-aminolevulinic acid (ALA)-induced porphyrins (FDAP), protoporphyrin IX (PpIX) accumulation can be macroscopically visualized. Interpretation of these data is still problematic because of the low reproducibility of the procedure and poor understanding of the mechanisms involved in PpIX tumor selectivity. In this study, PpIX accumulation is investigated in patients with psoriasis and actinic keratosis (AK) following FDAP. For this purpose, desquamated lesional and non-lesional skin were incubated with 20% ALA ointment for 3 h, FDAP was performed, and highly fluorescing lesional skin and non-lesional skin were biopsied. In extracts from these biopsies, PpIX, protein, and dsDNA were quantified by spectrofluorometry. Digital images acquired with FDAP were analyzed using image analysis software. PpIX per biopsy in lesional skin in both psoriasis and AK was significantly higher than in non-lesional skin (p < 0.05). When corrected for epidermal involvement, only lesional psoriatic skin showed significantly higher PpIX levels than non-lesional skin. The PpIX-ratio lesional:non-lesional skin (mean(pmol per mL)+/-SEM) was 4.12+/-0.91 in psoriasis and 1.96+/-0.24 in AK. In FDAP, the ratio of lesional:non-lesional skin was 1.77+/-0.06 in psoriasis and 1.37+/-0.07 in AK. Macroscopic fluorescence and PpIX content appeared to be well correlated (r = 0.73), thus making FDAP a good predictor of PpIX content.     

Enhanced expression of the high-affinity receptor for IgE (Fc(epsilon)RI) associated with decreased numbers of Langerhans cells in the lesional epidermis of atopic dermatitis

Epidermal Langerhans cells (LCs) and the high-affinity receptor for IgE (Fc(epsilon)RI) on their surface are considered important in the pathogenesis of atopic dermatitis (AD). We investigated the numbers of epidermal LCs and their Fc(epsilon)RI expression in patients with AD and healthy controls. Biopsy specimens taken from lesional skin from 17 patients with AD, non-lesional skin from five patients with AD and normal skin from five healthy individuals were immunohistochemically stained with a monoclonal antibody against CD1a or with either of two monoclonal antibodies against two different epitopes of Fc(epsilon)RI alpha chain. Many dendritic cells were positively stained with anti-CD1a antibody in the epidermis of each skin sample, and fewer cells were stained with anti-Fc(epsilon)RI antibodies. The numbers of epidermal LCs positive for Fc(epsilon)RI were significantly increased in both lesional and non-lesional skin from AD patients compared with those in normal skin, suggesting important roles of Fc(epsilon)RI+LCs in the pathogenesis of the disease. In contrast, the numbers of total epidermal LCs (CD1a-positive) were decreased in AD lesional skin compared with those in non-lesional skin from AD patients and in normal skin from healthy subjects. Together with our finding that the numbers of epidermal LCs were negatively correlated with the clinical severity of the AD lesions, we concluded that epidermal LCs may decrease in some conditions of AD, probably in lesions with severe inflammation.     

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。     

Alterations of glucosylceramide-beta-glucosidase levels in the skin of patients with psoriasis vulgaris

Hydrolysis of glucosylceramides by the enzyme glucosylceramide-beta-glucosidase (GlcCer'ase) results in ceramide, a critical component of the intercellular lamellae that mediates the epidermal permeability barrier. A disturbance of ceramide formation is supposed to influence the transepidermal water loss in common skin diseases like atopic eczema or psoriasis. The aim of this study was to investigate whether GlcCer'ase levels were altered in the skin of subjects with psoriasis vulgaris. Skin punch biopsies were taken from lesional and non-lesional psoriatic skin and GlcCer'ase was evaluated both at the RNA and at the protein level. Normal skin from surgical patients provided the baseline GlcCer'ase expression in healthy subjects. Our results show that GlcCer'ase mRNA expression was decreased in psoriatic non-lesional skin compared to normal controls in all cases. Interestingly, in lesional psoriatic skin the level of GlcCer'ase was increased compared to non-lesional skin in all cases. For the immunohistochemical analysis, we used a newly synthesized monoclonal antibody anti-human GBC (GlcCer'ase-GST fusion protein). The results confirmed that GlcCer'ase, mainly present in the upper epidermis, was decreased in psoriatic skin compared to normal control and was increased in lesional compared to non-lesional psoriatic skin. Our findings support the concept that alteration in water permeability barrier in lesional psoriatic skin can serve as a trigger for the upregulation of the expression of enzymes like GlcCer'ase with consequent stimulation of ceramide generation.     

The development of manifest psoriatic lesions is linked with the invasion of CD8+ T cells and CD11c+ macrophages into the epidermis

Koebner response was studied in 35 psoriatic patients. Two punch biopsies per patient were taken from non-lesional psoriatic skin before, and 6 h, 2 days, 7 days, 14 days and 21 days after, tape stripping. Alterations in the numbers of CD1+ Langerhans cells, CD4+ and CD8+ T cells and CD11c+ macrophages were mapped morphometrically. Results were compared with lesional and non-lesional psoriatic skin, and control skin. Nine of 35 patients were Koebner-positive. No statistically significant differences were noted between non-lesional psoriatic and control skin. CD4+ T cells increased in number 2 days after trauma in both the epidermis and the dermis, whereas epidermal CD8+ T cells and CD11c+ macrophages increased only in the Koebner-positive lesional skin after 7 days. The changes in lesions induced by tapestripping resembled those seen in lesional psoriatic skin (mature plaques). The number of CD1+ cells increased in mature psoriatic lesions only. It seems possible that trauma per se stimulates the accumulation of CD4+ T cells at the site of injury, but the development of manifest psoriatic lesions correlates with invasion of CD8+ T cells and CD11c+ macrophages into the epidermis.     

Increased levels of enkephalin following natural sunlight (combined with salt water bathing at the Dead Sea) and ultraviolet A irradiation

The opioid peptides enkephalins have been shown to modulate inflammatory responses and keratinocyte proliferation and differentiation. Furthermore, increased levels of enkephalin are present in psoriatic lesions. The purpose of the present study was to determine the effect of natural sunlight combined with salt water bathing in the Dead Sea on the methionine-enkephalin (e.n.k.) level in psoriatic skin. Ten patients were treated at the Dead Sea for 4 weeks, and keratotome biopsies were obtained before and after treatment. The amount of enkephalin extracted from the biopsies was measured by radioimmunoassay. Treatment at the Dead Sea resulted in a complete clinical clearance of psoriasis, and immunohistochemical stainings of lesional skin showed that the treatment decreased both epidermal thickness/parakeratosis and the dermal infiltration of CD3- and CD68-positive cells, although the number of CD3- and CD68-positive cells became normal in only two of the 10 cases. However, there was only a slight decrease in the mean enk levels (21%). Furthermore, the level of enk was high in non-lesional psoriatic skin after treatment at the Dead Sea, and immunostaining showed that, in some patients, the treatment induced a mild epidermal hyperplasia and a dermal infiltration of CD3- and CD68-positive cells. Enkephalin-like immunoreactivity was detected in the cytoplasm of both epidermal keratinocytes and dermal infiltrating cells. To determine whether the relatively high skin enk levels after treatment at the Dead Sea was caused by ultraviolet (UV) radiation, normal volunteers were exposed to a single dose of UVA and UVB (2 minimal erythema doses). UVA, but not UVB, irradiation stimulated the mean enk level in the irradiated skin by about sixfold. Furthermore, multiple whole-body UVA irradiations not only resulted in increased skin levels of enk, but also in increased plasma levels. In conclusion, natural sunlight combined with salt water bathing cleared psoriasis without causing a significant decrease in lesional enk levels. Furthermore, non-lesional enk levels were increased. These findings may be the result of a direct stimulatory effect of UVA irradiation on enk formation in the skin. It is possible that the increased circulating levels of enk after UV exposure may contribute to the beneficial effects of UVA irradiation.     

Increased expression of adhesion receptors in both lesional and non-lesional psoriatic skin

Adhesion receptors and their ligands play a vital role in the immune system. We studied the expression of different adhesion receptors, using single- and double-staining immunohistochemical techniques, in both lesional and non-lesional skin specimens from seven psoriasis patients and in skin biopsy specimens from eight normal healthy controls. Our results showed an overall increased expression of several adhesion receptors in both lesional and non-lesional psoriatic skin. We consistently found an increased expression in particular of ICAM-1 and E-selectin on endothelial cells, and ICAM-1 on T cells and Langerhans cells. In contrast, a weak expression of VCAM-1 was found on endothelial cells and mononuclear cells in lesional psoriatic skin specimens alone. Interestingly, LFA-1 was also expressed on Langerhans cells, with a greater frequency in skin from lesional than from non-lesional sites, but was never expressed in skin from normal healthy individuals. Furthermore, significantly increased numbers of Langerhans cells and T cells with a positive reactivity for MAb HECA-452 were found in both lesional and non-lesional psoriatic skin. We hypothesize that the enhanced expression of adhesion receptors on migrating immunocompetent cells and endothelial cells of psoriatic skin in general facilitates the increased influx of activated T lymphocytes and other immunocomponent cells into the skin, and thus underscores the generalized character of the disease.     

Vascular adhesion protein-1 (VAP-1) is overexpressed in psoriatic patients

BACKGROUND: Vascular adhesion protein (VAP)-1 is an adhesion molecule with an enzymatic activity that partakes in the migration process of lymphocytes. OBJECTIVES: The aim of this study was to investigate the expression of VAP-1 in the skin and serum of psoriatic patients. MATERIAL AND METHODS: Seventy-one patients suffering from psoriasis aged between 23 and 89 years were included in the study. The mean psoriasis severity assessed according to the psoriasis area and severity index was 14.2+/-9.6 points. The soluble VAP-1 serum concentration was evaluated by ELISA and VAP-1 expression in the skin (nine patients) immunohistochemically. RESULTS: The serum concentration of soluble VAP-1 was significantly higher in psoriatic patients than in healthy controls (403.4+/-130.8 ng/mL vs. 246.4+/-68.0 ng/mL; P<0.0001). No significant relationships were found between sVAP-1 concentration and studied clinical parameters, except the presence of pruritus. Mean number of VAP-1 positive vessels in psoriatic skin, both lesional (19.8+/-1.4) and non-lesional (9.4+/-1.4), was significantly higher than in healthy skin (5.4+/-1.5; P<0.005). Lesional psoriatic skin demonstrated significantly more VAP-1 positive vessels than non-lesional skin (P<0.01). CONCLUSIONS: Significant overexpression of VAP-1 in both lesional and non-lesional psoriatic skin and higher serum level of soluble VAP-1 in psoriatic patients may indicate the role of VAP-1 in chronic inflammation occurring in psoriasis. However, because of lack of correlation between soluble VAP-1 serum levels and psoriasis severity this hypothesis needs further investigation.     

Quantitation of tryptase- and chymase-containing mast cells in cutaneous lichen planus.

The distribution and density of tryptase- and chymase-positive mast cells in lesional and non-lesional cutaneous lichen planus (LP) was analysed. For this, enzyme-histochemical staining techniques and morphometrical measurements were applied. In non-lesional LP skin, chymase-positive cells (TC mast cells) showed a distribution similar to that found in both non-lesional psoriatic skin and in normal skin. Tryptase-positive cells (reflecting both T and TC mast cells), however, were increased in number in the upper dermis of non-lesional LP skin. In lesional LP skin, there were fewer chymase-positive cells in the upper dermis, whereas there were more tryptase-positive cells. In the upper dermis, no differences in the number of tryptase containing cells were detected between lesional and nonlesional LP skin. In lesions of LP and psoriasis, tryptase-positive mast cells are increased but differ in their distribution in the papillary dermis. In psoriatic lesions, tryptase-positive cells are frequently observed in epidermal contact, a feature very rarely seen in LP lesions. The present results suggest that the increased numbers of T mast cells in the upper dermis of nonlesional LP skin may be involved in initiating the LP lesion. It seems unlikely that mast cells could be responsible for the epidermal basal cell damage, though T mast cells do participate in the general inflammatory reaction.     

The development of manifest psoriatic lesions is linked with the appearance of ICAM-1 positivity on keratinocytes

The development of psoriatic lesions was studied in 36 psoriatic patients using the Koebner reaction induced by tape stripping. Two biopsies per patient were taken from non-lesional psoriatic skin before, and 6 h, 2 days, 7 days, 14 days and 21 days after tape stripping. Alterations in HLA-DR, ICAM-1, Ki-67 and FXIIIa positivities in both the dermis and the epidermis were estimated using immunohistochemical methods. A double staining for CD4⁺ and CD8⁺ T cells was also carried out to show their possible Ki-67 positivity. Results were compared with those from lesional (mature plaque) and non-lesional psoriatic skin, and control skin. Of the 36 patients, 9 were Koebner-positive. The most important finding in Koebner-positive psoriatic skin was the appearance of ICAM-1 positivity on epidermal keratinocytes simultaneously with the clinically observed lesion on day 7. The number of FXIIIa⁺ dendrocytes in the dermis was quite constant, and increased in mature psoriatic lesions only. The number of active HLA-DR⁺ immunocompetent cells increased in developing psoriatic lesions, being highest in mature lesions, but no Ki-67 positivity was detected in epidermal or dermal T cells in the psoriatic specimens. Based on these results, it is concluded that T cells divide and are activated extracutaneously in psoriasis, and also that ICAM-1/LFA-1 interactions are important in the recruitment of inflammatory cells and in controlling the effector cell functions.     

K16 expression in uninvolved psoriatic skin: a possible marker of pre-clinical psoriasis

BACKGROUND: K16, a type I keratin, is upregulated in hyperproliferative states including psoriasis. It has been used as a marker of psoriasis and its expression is upregulated in relapsing psoriasis and downregulating in resolving. We evaluated non-lesional psoriatic skin for K16 expression. METHODS: Sixty-seven non-lesional and lesional skin samples from patients with psoriasis and normal skin from 19 non-psoriatic patients were studied by immunohistochemistry on frozen sections with K16. RESULTS: Seventeen of 19 normal skin samples showed staining of basal cells in the deeper part of the rete ridges. Sixty-two non-lesional psoriatic skin samples showed intense basal staining of K16. Of the remaining five non-lesional samples, diffuse intense suprabasal staining in one, pan-epidermal staining in two, and no staining was seen in two samples. Suprabasal (37), diffuse (14), sandwich (12), and basal (3) pattern staining were seen in psoriatic skin. One psoriatic skin sample did not show any expression. CONCLUSION: Our results demonstrate that K16 expression is also observed in non-lesional psoriatic skin and may serve as a marker of preclinical psoriasis.     

寻常型银屑病患者血管内皮生长因子及单核细胞趋化因子-1表达的研究

目的 探讨血管内皮生长因子(VEGF)、单核细胞趋化因子-1(MCP-1)在银屑病患者皮肤中的表达及其意义。方法 用免疫组化法检测银屑病患者皮损、非皮损及正常人皮肤中VEGF、MCP-1的表达与分布。用双抗体夹心酶联免疫吸附法检测患者血清中VEGF、MCP-1水平。结果 ①银屑病患者皮损及非皮损中VEGF表达较正常人皮肤明显增强(P<0.05).皮损中MCP-1表达较非皮损及正常人皮肤明显增强(P<0.05).②患者血清中VEGF水平明显高于正常人(P<0.05),MCP-1水平与正常人比较差异无显着性(P>0.05).③皮损角质形成细胞中VEGF、MCP-1的表达与PASI评分无显着相关性(P>0.05)。结论 VEGF、MCP-1的表达增强在银屑病的发病机制中可能起重要作用。     

寻常性银屑病患者表皮中DNA总体甲基化水平检测

目的通过检测寻常性银屑病患者表皮DNA总体甲基化水平,探讨DNA甲基化在银屑病发生发展过程中的作用。方法采用荧光比色法检测寻常性银屑病患者表皮DNA总体甲基化水平,与同一患者非皮损部位及健康对照者表皮进行对照研究,并分析其与病情严重程度的相关性。以PASI评分评估银屑病病情严重程度。结果在30例银屑病患者皮损、非皮损部位表皮及28名健康对照者表皮中检测到不同程度的DNA甲基化,分别为(4.92±2.12)%、(2.85±1.35)%和(2.32±0.99)%。银屑病患者皮损部位表皮DNA总体甲基化水平显著高于同一患者的非皮损部位(P<0.0001)及健康对照者(P<0.0001),而非皮损部位DNA总体甲基化水平与健康对照者之间差异无统计学意义(P>0.05)。银屑病患者皮损部位表皮中DNA总体甲基化水平与PASI评分之间存在显著相关性(P<0.0001)。结论寻常性银屑病患者表皮中DNA总体甲基化水平明显升高,且与疾病严重程度呈正相关。     

过氧化物酶增殖物激活受体β/δ在银屑病角质形成细胞中的表达

【摘要】 目的 探讨过氧化物酶增殖物激活受体β/δ（PPARβ/δ）在银屑病患者表皮角质形成细胞（KC）中的表达和调节因素。 方法 免疫组化方法检测PPARβ/δ在银屑病患者皮损及非皮损表皮中的表达。分离、培养银屑病患者非皮损区和皮损区的KC,以RT-PCR和Western印迹法分别检测银屑病患者皮损区和非皮损区KC中PPARβ/δ mRNA和蛋白质的表达水平。利用PPARβ/δ外源性激动剂GW501516及Ca2+刺激银屑病非皮损区KC,观察其对PPARβ/δ表达的调节影响。 结果 免疫组化显示,银屑病皮损区PPARβ/δ的表达强度显著高于正常对照组（t = 19.28,P < 0.01）和非皮损区（t = 23.26,P < 0.01）。银屑病皮损区PPARβ/δ mRNA和蛋白质的表达水平均高于正常对照组（P < 0.01）和非皮损区（P < 0.01）。10 ng/ml GW501516最大效能促进PPARβ/δ的表达（P < 0.01）;1.0 mmol/L Ca2+对KC中PPARβ/δ的表达促进效应最明显（P < 0.01）。 结论 PPARβ/δ在银屑病患者皮损区表达显著升高,GW501516 和Ca2+能够促进角质形成细胞PPARβ/δ表达水平。     

Intraepidermal lymphocytes in psoriatic lesions are activated GMP-17(TIA-1)+CD8+CD3+ CTLs as determined by phenotypic analysis

The onset and persistence of psoriatic lesions are linked to the presence of an inflammatory infiltrate of CD3+ lymphocytes that includes CD4+ and CD8+ subsets. Since a primary susceptibility factor for psoriasis is the Class I HLA-Cw6 molecule, we set out to learn more about the features of the epidermal CD8+ lymphocytes. The markers tested were GMP-17, a cytotoxic granule protein found in activated cytotoxic lymphocytes (CTLs), and the alpha chain of the IL-2 receptor (CD25), a plasma membrane molecule found on activated T cells. Lymphocytes in lesional skin expressed the GMP-17 protein, whereas lymphocytes in non-lesional skin, resolving lesional skin and normal skin had little or no GMP-17. By flow cytometry analysis, lesional epidermal GMP-17+ cells were CD8+CD3+, with a subpopulation expressing the activation marker CD25+. Due to the abundance of activated GMP-17+CD8+CD3+ lymphocytes (the phenotype of activated cytotoxic cells) in psoriatic lesions compared to non-lesional and normal skin, we hypothesize that they are contributing directly to the psoriatic phenotype.     

银屑病患者角质形成细胞VEGF表达的研究

目的　研究银屑病发病与血管内皮生长因子 (VEGF)的关系 ,探讨银屑病可能的发病机制。方法　①用免疫组化法检测银屑病患者皮损和非皮损处皮肤、正常健康人皮肤及体外培养的银屑病患者和正常人角质形成细胞(KC)VEGF的表达 ;②用双抗体夹心ELISA法检测银屑病患者及正常人KC培养上清液中VEGF含量。结果　①银屑病皮损处VEGF表达明显高于非皮损处和正常人皮肤 (P均 <0 .0 0 1) ,非皮损处与正常人皮肤VEGF表达也有显著性差异 (P <0 .0 5 ) ;②体外培养的银屑病皮损处和非皮损处KCVEGF表达明显高于正常人 (P均 <0 .0 0 1) ;银屑病皮损处KC与非皮损处KC相比VEGF表达也有显著性差异 (P <0 .0 5 ) )。结论　VEGF可能参与银屑病的发病。