A single intradermal injection of IFN-γ induces an inflammatory state in both non-lesional psoriatic and healthy skin

Psoriasis is a chronic, debilitating, immune-mediated inflammatory skin disease. As IFN-γ is involved in many cellular processes, including activation of dendritic cells (DCs), antigen processing and presentation, cell adhesion and trafficking, and cytokine and chemokine production, IFN-γ-producing Th1 cells were proposed to be integral to the pathogenesis of psoriasis. Recently, IFN-γ was shown to enhance IL-23 and IL-1 production by DCs and subsequently induce Th17 cells, which are important contributors to the inflammatory cascade in psoriatic lesions. To determine whether IFN-γ indeed induces the pathways expressed in psoriatic lesions, a single intradermal injection of IFN-γ was administered to an area of clinically normal, non-lesional (NL) skin of psoriasis patients and biopsies were collected 24 hours later. Although there were no visible changes in the skin, IFN-γ induced many molecular and histological features characteristic of psoriatic lesions. IFN-γ increased a number of differentially expressed genes in the skin, including many chemokines concomitant with an influx of T cells and inflammatory DCs. Furthermore, inflammatory DC products tumor necrosis factor (TNF), inducible nitric oxide synthase, IL-23, and TNF-related apoptosis-inducing ligand were present in IFN-γ-treated skin. Thus, IFN-γ, which is significantly elevated in NL skin compared with healthy skin, appears to be a key pathogenic cytokine that can induce many features of the inflammatory cascade of psoriasis.     

Upregulation of RANTES in psoriatic keratinocytes: a possible pathogenic mechanism for psoriasis

Intraepidermal collections of neutrophils and lymphocytes are unique features of the inflammatory reaction of psoriasis. Migration of leukocytes from dermis to the epidermis suggests a role for chemotactic agent(s). In recent years, increased levels of chemokines such as IL-8 , GRO-a and MCP-1 have been reported in the keratinocytes of psoriatic tissue. IL-8 and GRO-alpha belong to a subfamily (C x C) class and MCP-1 is a beta chemokine. In this study, we investigated RANTES, which is a beta chemokine (C-C class); RANTES has been found to be associated with various cell-mediated hypersensitive disorders. We obtained eight skin biopsies from chronic psoriatic plaques, and five biopsies each from non-lesional psoriatic skin, lichen planus, eczematous dermatitis and skin from healthy controls. Snap-frozen samples were cut into 7 microm cryosections and stained with 6 mg/ml of monoclonal anti-RANTES mouse IgG (DNAX, Palo Alto, CA). Standard immunohistochemistry techniques were applied. RANTES was detected only in the keratinocytes. The number of keratinocytes in per mm2 of epidermis stained for RANTES were 116.79+/-98.42 in psoriatic tissues compared to 32.00+/-46.05 (p<0.05), 6.39+/-3.59 (p<0.01), 2.64 +/-1.15 (p<0.01) and 3.53+/-5.26 (p<0.01), respectively, in the non-lesional, lichen planus, eczematous lesions and normal skin. This is the first study to report that the keratinocytes of psoriatic tissue express high levels of RANTES compared to the controls. IL-8 and related molecules (C x C class) are predominantly chemotactic for neutrophils and MCP-1 is a strong chemotactic factor for monocytes. In contrast, RANTES is chemotactic for memory T cells and activated naive T cells. Increased amounts of RANTES as reported here provide an explanation for migration of the activated T cells to the epidermis of the psoriatic lesions. In addition, RANTES activates T cells. These results suggest that RANTES may have a significant role in the inflammatory process of psoriasis. Our findings further substantiate a regulatory role for keratinocytes in the inflammatory process of psoriasis.     

过氧化物酶体增殖物激活受体在寻常性银屑病患者表皮中的表达

目的 研究过氧化物酶体增殖物激活受体（PPAR）在寻常性银屑病患者表皮角质形成细胞中的表达和意义。方法 采用免疫组化方法检测PPARα、β/δ、γ在5例正常人表皮、17例寻常性银屑病患者皮损及非皮损表皮中的表达,并用图像分析方法进行半定量分析。结果 PPARα、β/δ、γ在正常人表皮角质形成细胞中均有不同程度的细胞核表达;在银屑病皮损表皮中的表达强度均较非皮损处下降（P ＜ 0.01）。在银屑病非皮损表皮中,PPARβ/δ、γ的表达强度均较正常人表皮明显升高（P ＜ 0.01）。结论 PPARα表达下调可能参与了银屑病表皮角质形成细胞过度增生和分化不全的病理过程,而PPARβ/δ、γ在维持表皮细胞正常增生分化稳态中可能发挥协同作用。     

SERPINB2 and miR-146a/b are coordinately regulated and act in the suppression of psoriasis-associated inflammatory responses in keratinocytes

Psoriasis is a chronic inflammatory skin disease with numerous involved factors. miR-146a and miR-146b (miR-146a/b) are anti-inflammatory miRNAs that are increased in psoriatic skin. SERPINB2 has been shown to be upregulated in the inflammation and infections. Here we aimed to study the relationship between miR-146a/b and SERPINB2 and to delineate the role of SERPINB2 in association of plaque psoriasis. We report increased SERPINB2 expression in the skin of psoriasis patients, which was in a positive relationship with psoriasis severity and in a negative relationship with miR-146a/b in psoriatic lesions. In cultured keratinocytes, both cellular and secreted SERPINB2 levels were strongly induced in response to IFN-γ and TNF-α. Interestingly, SERPINB2 mRNA was downregulated by IL-17A and the combination of TNF-α and IL-17A at time points when miR-146a was increased. The predicted binding site for miR-146a/b in 3’ untranslated region of SERPINB2 revealed no activity in luciferase assay, while siRNA silencing of miR-146a/b direct targets IRAK1 and CARD10 resulted in reduced expression of SERPINB2, suggesting that miR-146a/b indirectly control SERPINB2 expression in the skin. The siRNA silencing of SERPINB2 increased the expression of IL-8, CXCL5 and CCL5 and migration of neutrophils revealing its anti-inflammatory role in keratinocytes. Our data together suggest that SERPINB2 and miR-146a/b are part of disease-related network of molecules that are coordinately regulated and act in controlling the inflammatory responses in psoriatic skin.     

Interleukin (IL)-17 versus IL-27: opposite effects on tumor necrosis factor-α-mediated chemokine production in human keratinocytes

Tumor necrosis factor (TNF)-α is known to play a pivotal role in the pathogenesis of psoriasis. TNF-α has been shown to act directly on keratinocytes, thereby inducing the production of various kinds of chemokines, which contributes to the infiltration of leucocytes into the psoriatic lesions. Recent studies have shown that both interleukin (IL)-17 and IL-27 are increased in psoriatic lesional tissue. However, the interactions between TNF-α, IL-17 and IL-27 in chemokine production by keratinocytes have not been fully elucidated. Here, we examined in human keratinocytes how TNF-α, IL-17 and IL-27 affect production of chemokines that are involved in the pathogenesis of psoriasis. We found that IL-17 and IL-27 exert opposite effects on TNF-α-mediated chemokine production. This suggests that lesional balance of IL-17 and IL-27 is involved in the recruitment of T cells, natural killer cells, neutrophils, monocytes or dendritic cells, thereby affecting inflammation in skin diseases.     

转录因子CCAAT/增强子结合蛋白α在银屑病皮损中的表达及意义

目的 探讨转录因子CCAAT/增强子结合蛋白α（C/EBP-α）在寻常性银屑病皮损中的表达及与角质形成细胞异常增殖及皮损严重程度间的相关性。 方法 用免疫组化二步法及Western印迹检测30例寻常性银屑病患者皮损和30例健康对照皮肤的表皮中C/EBP-α。免疫组化法检测Ki-67的表达,并根据Ki-67阳性表达数量计算增殖指数,Pearson相关分析法分析寻常性银屑病皮损中C/EBP-α的表达水平与角质形成细胞Ki-67增殖指数及银屑病皮损面积和严重程度指数（PASI评分）间的相关性。 结果 C/EBP-α主要在角质形成细胞胞质中表达,寻常性银屑病皮损中C/EBP-α的表达较健康对照皮肤明显下调（t = 7.82,P ＜ 0.05）。Ki-67主要在角质形成细胞胞核中表达,寻常性银屑病皮损中角质形成细胞的增殖指数明显高于健康对照皮肤（t = 4.54,P ＜ 0.05）。经Pearson相关分析,寻常性银屑病皮损中C/EBP-α表达水平与增殖指数呈负相关,与PASI评分呈负相关。Western印迹结果亦显示,C/EBP-α在银屑病皮损处的表达量显著下调。 结论 C/EBP-α在寻常性银屑病皮损中表达下调,可能参与了寻常性银屑病的发病过程。     

甲氨蝶呤对银屑病患者皮损T细胞内IFN-γ mRNA影响的研究

目的研究甲氨蝶呤(MTX)对银屑病皮损内γ干扰素(IFNγ)的影响,探讨其对银屑病的治疗机理。方法随机选择12例正常对照者和13例中重度银屑病患者,所有患者治疗前和治疗6周后行皮肤活检。利用荧光定量聚合酶链反应法测定12例正常对照和13例银屑病患者治疗前及治疗6周后皮损细胞内IFNγmRNA的定量表达。结果银屑病皮损细胞内IFNγmRNA水平明显高于正常对照者(P=0.001)。银屑病患者经过MTX治疗6周后,皮损明显改善,皮损细胞内IFNγmRNA的水平明显低于治疗前的水平(P=0.007),但与正常对照者皮肤比较差异无显著性(P=0.999)。结论MTX能调节银屑病皮损的局部免疫功能,抑制皮损T细胞内IFNγmRNA的过度表达,恢复Th1型细胞因子平衡,这可能是MTX治疗银屑病的作用机制之一。     

γ-干扰素诱导银屑病皮损角质形成细胞MAPK活性的研究

目的研究γ-干扰素(IFN-γ)诱导银屑病皮损角质形成细胞的丝裂原活化蛋白激酶(MAPK)活性,以及MAPK在银屑病发病中的意义。方法在培养的银屑病患者及正常人角质形成细胞中加入IFN-γ、genistein及二甲基亚砜(DMSO)进行刺激,检测MAPK的活性。结果银屑病皮损角质形成细胞中MAPK活性较正常人高,且在IFN-γ的刺激下活性均增加,而加入genistein时两组MAPK活性明显下降,两组接受IFN-γ、genistein刺激后,MAPK活性变化的比较差异有统计学意义(P0.01)。结论 IFN-γ对银屑病角质形成细胞MAPK活性有明显促进作用。     

银屑病患者皮损表皮生长因子及其受体的检测

用抗表皮生长因子（ＥＧＦ）多克隆抗体、抗表皮生长因子受体（ＥＧＦＲ）单克隆抗体及ＡＢＣ免 疫酶标技术，对２０例寻常型银屑病患者皮损及１０例正常人皮肤进行观察。结果表明：①正常人皮肤及 银屑病非皮损区皮肤ＥＧＦ及ＥＧＦＲ主要分布在表皮基底细胞层及基底层上部。②银屑病进行期皮损 ＥＧＦ及ＥＧＦＲ分布于表皮各层，表皮中、上层含量明显升高。③经有效治疗消退期皮损ＥＧＦ及ＥＧＦＲ 从角质层开始消退，分布趋于正常。提示ＥＧＦ及ＥＧＦＲ对银屑病皮损角肮细胞过度增殖及异常分化起 重要作用。     

Systemic photochemotherapy decreases the expression of IFN-γ, IL-12p40 and IL-23p19 in psoriatic plaques

Psoriasis vulgaris (PV) is a chronic skin disease with unclear pathogenesis. In the present study we investigated the effect of systemic photochemotherapy (PUVA therapy- psoralen and UVA therapy) on the expression of IFN-γ, IL-12p40 and IL-23p19 in lesional psoriatic skin. Fifteen patients with chronic plaque type psoriasis selected to be treated with PUVA therapy were recruited for this study. Expression of IFN-γ, IL-12p40 and IL-23p19 in psoriatic lesions before and after twenty PUVA treatments was established by using immunohistochemistry (IHC). A significant decrease in expression (p?相似文献   

Serum levels of interleukin-8, tumor necrosis factor-α and γ-interferon in Egyptian psoriatic patients and correlation with disease severity

Psoriatic plaques have been shown to contain increased levels of pro-inflammatory cytokines. Also, serum levels of several cytokines have been reported elevated in psoriatic patients. It is postulated that changes in cytokine production both locally and systemically could be useful in monitoring disease activity. The aim of this study was to evaluate serum cytokine profile of interleukin (IL)-8, γ-interferon (IFN-γ) and tumor necrosis factor-α (TNF-α) in Egyptian psoriatic patients by enzyme-linked immunosorbent assay (ELISA) technique and to correlate these levels with disease severity. We analyzed serum samples from 60 Egyptian patients (31 females and 29 males) with a mean age of 40.2 ± 17.4 years with active psoriasis, and 21 healthy volunteers for major T-helper type 1 cytokines using the ELISA technique. The disease severity, including erythema, induration and scales, was assessed by Psoriasis Area and Severity Index (PASI) score. TNF-α and IFN-γ were markedly elevated in all sera from psoriatic patients. TNF-α was found a more efficient predictor for disease severity than IL-8 and IFN-γ using three receiver-operator curves with accuracy. IL-8 was also moderately elevated and correlated with the age of patients (r = 0.28). We have obtained evidence that TNF-α in our study was found to be more useful than the other two tested cytokines, IL-8 and IFN-γ as a follow-up marker for monitoring disease severity in Egyptian psoriatic patients. A positive correlation between lL-8 and the age of the patients was also noted.     

进行性斑状色素减少症发病机制初步探讨

目的探讨进行性斑状色素减少症(progressive macular hypomelanosis,PMH)患者皮损中分离出的痤疮丙酸杆菌对人角质形成细胞(human keratinocytes,HaCaT)细胞分泌干扰素(interferon,IFN)-γ、白细胞介素(interleukin,IL)-6、肿瘤坏死因子(tumor necrosis factor,TNF)-α的影响。方法体外培养HaCaT细胞株,分别加入分离自PMH的痤疮丙酸杆菌、痤疮丙酸杆菌标准菌株(NCTC737),酶联免疫吸附试验(enzyme-linked immunosorbent assay,ELISA)方法测定细胞上清液中IFN-γ、IL-6、TNF-α的分泌量。结果 PMH患者中分离的痤疮丙酸杆菌与角质形成细胞HaCaT细胞株共培养后,能促进角质形成细胞分泌IFN-γ和IL-6,与空白组比较,有明显升高,差异有统计学意义(P0.05);与痤疮丙酸杆菌标准菌株NCTC737相比也升高,差异有统计学意义(P0.05)。结论进行性斑状色素减少症皮损中分离出的痤疮丙酸杆菌可刺激HaCaT细胞分泌IFN-γ、IL-6、TNF-α,提示可能是皮损色素减退的原因之一。     

寻常型银屑病患者中性粒细胞分泌炎性因子的研究

目的观察寻常型银屑病患者外周血中性粒细胞是否存在分泌炎性因子的异常,探讨中性粒细胞参与银屑病的机制。方法作中性粒细胞培养,应用酶联免疫吸附法检测脂多糖(LPS)刺激前后中性粒细胞分泌白细胞介素-8(IL-8)、肿瘤坏死因子-α(TNF-α)的水平,应用细胞色素C还原法检测LPS刺激前后中性粒细胞超氧阴离子(Superox-ide anion)的水平。结果在脂多糖刺激前、后,银屑病患者外周血中性粒细胞分泌的IL-8、TNF-α以及Superoxide anion水平均较正常人显著增高(P<0.05),且进行期患者上述炎性因子的分泌水平显著高于静止期患者(P<0.01)。银屑病患者病情严重程度(PASI评分)与中性粒细胞于脂多糖刺激前、后IL-8、TNF-α及Superoxideanion水平均呈正相关(P<0.05)。结论银屑病患者存在外周血中性粒细胞分泌炎性因子的异常,该种异常可能参与银屑病的发病与病情进展,其中可能有感染因素的介导。     

Involvement of IL-17F via the induction of IL-6 in psoriasis

Recently, the important role of T helper 17 (Th17) cells in psoriasis has been clarified; however, the role of IL-17F produced by Th17 cells is still not fully understood. IL-6 exhibits multiple biologic functions, such as regulation of immunological responses including those in psoriatic reactions. Therefore, we examined the production of IL-6 protein in normal human epidermal keratinocytes (NHEKs) stimulated by IL-17F, TNF-α, IL-17A, and IL-17A in combination with TNF-α, and PBS control. We then examined the expression of IL-6 mRNA in mouse skin after intradermal injection of IL-17F. Finally, IL-17F expression in skin biopsy specimens from psoriasis patients was examined by immunohistochemistry. The results showed that IL-17F induced production of IL-6 in NHEKs in a time-dependent manner. This could be attenuated by chimeric inhibitor blocking the IL-17 receptor. The amounts of IL-6 stimulated by IL-17F were much higher than those stimulated by TNF-α or IL-17A. IL-6 was also significantly upregulated via synergistic stimulation with IL-17A plus TNF-α. The expression of IL-6 mRNA 24 h after IL-17F injection in the mouse skin was 3.2-fold higher than that in the control group. Immunohistochemistry of inflammatory cells in the dermis demonstrated a large number of CD4⁺ T cells showing IL-17F positivity in psoriatic skin lesions, but few or none in non-lesional psoriatic skin. Our results indicate that IL-17F produced by CD4⁺ T cells causes the inflammation in psoriasis partly through induction of IL-6 in keratinocytes.     

E-钙黏素,P-钙黏素在进行期银屑病皮损中的检测

目的研究E-钙黏素(E-cadherin),P-钙黏素(P-cadherin)在寻常性银屑病中的表达。方法用免疫组化方法检测正常皮肤组织及进行期银屑病皮损中E-cadherin,P-cadherin蛋白的表达。结果E-cadherin蛋白在正常人皮肤组织表皮全层表达,在进行期银屑病皮损表达在颗粒层和棘层上部及基底层表达明显下降或缺失;在正常人皮肤组织中,P-cadherin主要表达于基底层,而在银屑病皮损中则强烈表达于表皮全层。结论E-cadherin表达的下调和P-cadherin表达的上调,可能与银屑病角质形成细胞高度增殖有关。     

Human keratinocytes express fractalkine/CX3CL1

BACKGROUND: fractalkine/CX3CL1 is a unique chemokine that has properties of both chemoattractants and adhesion molecules. The major source of this chemokine in the skin is still controversial. OBJECTIVE: studies were undertaken to determine the expression of fractalkine in human skin. METHODS: RT-PCR, Western blotting, and immunostaining were performed with normal human epidermal keratinocytes (NHEK) and HaCaT cells, human keratinocyte cell line, for the presence of fractalkine. Biopsy specimens of normal and diseased skin were also investigated. RESULTS: we identified that NHEK and HaCaT cells expressed fractalkine mRNA and protein. The combination of tumor necrosis factor (TNF)-alpha and interferon (IFN)-gamma upregulated their expression by NHEK. Immunohistochemistry demonstrated fractalkine expression in keratinocytes in lichen planus and psoriasis vulgaris. RT-PCR also showed that lesional skin of psoriatic patients expressed higher levels of fractalkine mRNA than non-lesional skin from the same patients. CONCLUSION: these results suggests that keratinocytes strongly express fractalkine in lichen planus and psoriasis vulgaris and that the fractalkine-CXC3CR1 system in the diseased skin can be a target for the treatment.