Fas、FasL表达在银屑病发病机理中的作用

目的 探讨Ｆａｓ,ＦａｓＬ介导的细胞凋亡引发的免疫调节在银屑病发病机理中的作用及意义。方法 采用免疫组化方法和原位末端标记方法研究银屑病患者不同期皮损中Ｆａｓ,ＦａｓＬ表达与细胞凋亡,局部单一核细胞浸润程度之间的关系,结果 （１）角质形成细胞既可表达Ｆａｓ,又可表达ＦａｓＬ二者分布基本一致,Ｆａｓ,ＦａｓＬ表达强的部位角质形成细胞凋亡明显,而局部单一核细胞浸润减少,（２）患者进行期斑块型皮损中Ｆａ     

寻常性银屑病皮损中bcl—2 Fas及FasL的表达

目的 探讨银屑病表皮角质形成细胞异常增殖和分化机制。方法 采用免疫组化技术对１０例建党性银屑病皮损中ｂｃｌ－２、Ｆａｓ及ＦａｓＬ表达进行了检测。结果 在建党惺 银屑病皮损中,７例表达ｂｃｌ－２,且表达部位主要位于棘细胞层上方和角质层内角化不全细胞;１０例表达Ｆａｓ,表达部位与ｂａｌ－２相似‘浸润炎性细胞均不表达ＦａｓＬ。相关分析表明,角质形成细胞ｂｃｌ－２和Ｆａｓ表达强度呈显著性相关（ｒ＝－０．７     

银屑病中细胞凋亡相关基因bcl-2、Fas、bax的检测

为了细胞凋亡相关基因ｂｃｌ－２、Ｆａｓ、ｂａｘ在银屑病发病中的意义,采用免疫组化ＡＢＣ法、ＳＡＢＣ法检测了这几种基因在１５例银屑病中的表达。结果发现银屑病的角质形成细胞中抑凋亡基因ｂｃｌ－２几乎不表达,促凋亡基因Ｆａｓ、ｂａｘ阳性表达。揭示促凋亡基因Ｆａｓ、ｂａｘ在银屑病中发病起重要作用,而抑凋亡基因ｂｃｌ－２作用可能不大。     

正常新生小鼠角质形成细胞和成纤维细胞Fas和Fas配体的表达

Ｆａｓ和Ｆａｓ配体（ＦａｓＬ）结合可导致表达Ｆａｓ的细胞凋亡,是细胞凋亡的一个主要途径［１］。已经证明Ｆａｓ表达于正常角质形成细胞和成纤维细胞中,但是到目前为止还没有ＦａｓＬｍＲＮＡ表达在正常角质形成细胞中的直接证据。我们采用高敏感的ＲＮＡ酶保护法,半定量地检测了正常新生小鼠角质形成细胞和成纤维细胞的Ｆａｓ和ＦａｓＬｍＲＮＡ,并用流式细胞仪检测了细胞表面表达Ｆａｓ和ＦａｓＬ蛋白的阳性细胞数,以阐明Ｆａｓ及ＦａｓＬ在角质形成细胞和成纤维细胞凋亡中的作用,为研究正常皮肤生长、凋亡及某些皮肤病的发病机理提供…     

Fas Bax和bcl-2蛋白在银屑病病人表皮细胞中的表达

目的观察银屑病病人表皮细胞凋亡中凋亡基因Ｆａｓ、Ｂａｘ（ｂ ｃｅｌ相关基因）和凋亡抑制基因ｂｃｌ ２（Ｂ ｃｅｌＬｙｍｐｈｏｍａ／Ｌｅｕｋｅｍｉａ２）的作用及其相互关系。方法采用免疫组化染色法在３３例银屑病皮损标本中,观察了Ｆａｓ、Ｂａｘ及ｂｃｌ ２蛋白的表达。结果发现３３例银屑病皮损标本中,Ｆａｓ２９例阳性表达;Ｂａｘ２３例阳生;３３例ｂｃｌ ２表达皆阴性。５例正常对照中,Ｆａｓ及Ｂａｘ皆阴性,ｂｃｌ ２在基底层细胞中阳性。结论结果提示Ｆａｓ和Ｂａｘ蛋白的高表达、ｂｃｌ ２的不表达与银屑病损害中表皮细胞凋亡增多有关。     

Fas抗原及Fas配体在红斑狼疮患者皮损中的表达

目的 研究Ｆａｓ抗原及Ｆａｓ配体（Ｆａｓ－Ｌ）在红斑狼疮皮损中的表达情况。方法 应用免疫组化技术检测２５例系统性红斑狼疮（ＳＬＥ）及１４例盘状红斑狼疮（ＤＬＥ）不同病程的皮损中Ｆａｓ抗原及Ｆａｓ－Ｌ的表达。结果 ＳＬＥ及ＤＬＥ早期皮损朊细胞Ｆａｓ抗原表达强度显著高于正常皮肤（Ｐ〈０．０１）,与病程呈负相关（Ｐ〈０．０５）,且真皮中单一核细胞亦有Ｆａｓ抗原表达;红斑狼疮患者皮损及正常皮肤的角朊细胞均     

银屑病患者表皮及真皮中Bcl-X、Bcl-2、Bax表达的免疫组化研究

目的 探讨银屑病患者细胞增殖与凋亡的调节。方法 用免疫组化ＳＰ法检测银屑病皮损及非皮损中Ｂｃｌ－Ｘ、Ｂｃｌ－２、Ｂａｘ的表达情况。结果 银屑病皮损中,Ｂｃｌ－Ｘ在表皮各层、真皮炎症细胞及血管内皮的表达均较正常明显增高;Ｂａｘ在颗粒层与棘层的表达轻度增高。上述异常在非皮损中已经部分存在,且隍未完全恢复正常。而Ｂｃｌ－２表达与正常相似,局限于基底层黑素细胞,角质形成细胞未是性。结论 银屑病中角质形成细     

γ—干扰素诱导角质形成细胞凋亡及其Fas抗原表达研究

目的：探讨γ－干扰素在银屑病发病中的作用。方法 通过流式细胞仪测定角持形成细胞中亚二倍体细胞含量、片段化DNA分析及AnnexinV法检测经γ－干扰素诱导的角质形成细胞凋亡;采用组织化学、流式细胞仪测定经γ－干扰素作用后的角质形成细胞Fas抗原表达。结果 γ－干扰素上调角质形成细胞Fas抗原表达（P＜0．01）,诱导角质形成细胞凋亡（P＜0．01）。结论 γ－干扰素可能通过上调角质形成细胞Fas抗原表达,进而诱导角质形成细胞凋亡而参与银屑病发病。     

银屑病患者Fas及Bcl-2的表达及中药的作用

为探讨银屑病的细胞凋亡机制及中药对其影响,我们对寻常型进行期银屑病患者皮损Fas和Bcl-2的表达进行了光镜及电镜原位杂交研究,探讨了电镜原位杂交的实验方法,观察了8种中药对银屑病患者皮损培养细胞中Fas和凋亡表达的抑制作用。并检测了经银屑病患者白细胞刺激的体外培养角质形成细胞(KC)Fas和凋亡表达的抑制作用,力图筛选出有效的中药。     

白介素8及其受体CXCR2在银屑病角质形成细胞中的表达

目的 观察白介素8（IL－8）及基受体CXCR2在银屑病角质形成细胞中的表达及在银屑病的临床及病理表现中的作用。方法 培养银屑病患者皮损处角质形成细胞，通过微孔小室实验检测其上清液的趋化功能，通过酶联免疫吸附法（ELISA）检测上清液中IL－8的表达，通过流式细胞仪分析银屑病患者皮损处角质形成细胞的趋化因子受体CXCR2的表达。结果 银屑病患者皮损处角质形成细胞分泌上清液对中性粒细胞的趋化能力明显强于正常对照组，其分泌的IL－8水平也高于正常人，皮损处角质形成细胞CXCR2的表达也明显强于正常对照组。结论 银屑病患者皮损局部表面出的角质形成细胞高度增殖与角质形成细胞高分泌、高表达具有促增殖作用的IL－8及其受体CXCR2有关，同时皮损局部大量的炎性细胞的浸润部分可能是由于角质形成细胞高分泌具有趋化能力的IL－8，它们可能在银屑病的发生、发展中起着重要作用。     

寻常性银屑病患者皮损中Caspase-3和bcl-xL的表达

目的 探讨Caspase-3和bcl-xL在银屑病皮损中的表达及意义。方法 采用免疫组化法对26例寻常性银屑病患者的皮损及其周边外观正常皮肤和10例正常人对照皮肤中Caspase-3和bcl-xL的表达进行了检测。结果 正常人对照皮肤、银屑病皮损及其周边外观正常皮肤的表皮均表达Caspase-3,其中皮损处的表达明显增强(P<0.0001);除皮损表皮中散在表达bcl-xL外,正常人对照皮肤、银屑病皮损周边外观正常皮肤的表皮中不表达bcl-xL。结论 Caspase-3和bcl-xL可能通过诱导银屑病皮损角质形成细胞的凋亡而参与了银屑病的发病。     

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。     

Effect of vitamin D<Subscript>3</Subscript> on the increased expression of Bcl-x<Subscript>L</Subscript> in psoriasis

Psoriasis is a chronic skin disease characterized by epidermal hyperproliferation, which may be regulated by several mechanisms including apoptosis. In this study, we detected DNA fragmentation by the terminal deoxynucleotide transferase-mediated dUTP nick-end labeling (TUNEL) method and immunohistochemically examined the expression of Bcl-x and Bax in psoriasis. We determined the expression of bcl-xL mRNA by RT-PCR, and also determined the effect of vitamin D(3) (VD3) on bcl-xL mRNA expression in cultured normal human keratinocytes by RT-PCR, and the expression of Bcl-xL in psoriatic lesions before and after topical application of VD3. A large number of TUNEL-positive cells as well as Bcl-xL - and Bax-positive cells were observed throughout the epidermis in psoriatic lesions. Whereas, in nonlesional and normal skin, only a few TUNEL-positive cells were observed and only the lower epidermis showed positive staining for Bcl-x and Bax. We also observed higher expression of bcl-xL mRNA in psoriatic lesions than in nonlesional and normal skin. The expression of bcl-xL mRNA in cultured normal human keratinocytes stimulated or not with IFN-gamma and PMA was suppressed by VD3 in a dose-dependent manner, and the expression of Bcl-xL, but not Bax, in psoriatic lesional skin decreased after topical application of VD3 for 4 weeks. In conclusion, it is suggested that the apoptotic process in psoriatic lesions is in part regulated by Bcl-xL, and decreasing the expression of Bcl-xL by treatment with VD3 might ameliorate psoriatic lesions by contributing to the completion of the apoptotic process.     

Infliximab restores the balance between pro- and anti-apoptotic proteins in regressing psoriatic lesions

Background Psoriasis and psoriatic arthritis are treated very efficaciously with infliximab, a chimaeric human–murine antitumour necrosis factor (TNF)‐α antibody. As we reported earlier, infliximab, besides its anti‐inflammatory properties, induces a caspase‐independent programmed cell death of psoriatic keratinocytes. Objectives To elucidate this finding further, we investigated the epidermal expression of proteins involved in the mitochondria‐dependent (intrinsic) pathway of cell death. Methods Quantification of proteins with pro‐ (p53, AIF, Bax) and anti‐apoptotic functions (Bcl‐2, Bcl‐XL) and of NF‐κB was performed by means of immunohistochemistry and digital image analysis of the staining of nonlesional skin and lesional psoriatic skin from patients treated with infliximab at weeks 0, 2 and 6. Results Serial biopsies from psoriatic plaques of samples taken at days 0, 5, 14 and 21 of therapy demonstrated a significant downregulation of anti‐apoptotic proteins Bcl‐2, Bcl‐XL and NF‐κB during treatment and, in parallel, a significant upregulation of pro‐apoptotic proteins p53, Bax and AIF. These differences in expression correlated with decreases in epidermal thickness and clinical outcome (Psoriasis Area and Severity Index). At day 21, expression levels of apoptosis‐related proteins in lesional skin approximated those found in nonlesional skin. Conclusions Our data therefore suggest that TNF‐targeting agents may induce the regression of psoriasis at least in part by normalizing the expression of apoptosis‐related proteins in lesional keratinocytes.     

The behaviour of Bcl-2, Bax and Bcl-x in Darier's disease

BACKGROUND: Darier's disease (DD) is a rare autosomal dominant disorder of keratinization caused by a mutation of the ATP2A2 gene. There is little information on the behaviour of Bcl-2, Bax and Bcl-x in DD. OBJECTIVES: To investigate the dynamic control and the behaviour of Bax, Bcl-2 and Bcl-x in DD. We asked whether members of the Bcl-2 family might manifest their effects through modulation of intracellular calcium signalling or whether the gene that encodes the sarco/endoplasmic reticulum Ca2+ ATPase isoform 2 (SERCA2) modulates the Bcl-2 family in the regulation of apoptosis in DD. Methods Immunohistochemical methods were used. RESULTS: There was no immunoreactivity for Bcl-2 and Bcl-x in epidermal keratinocytes in lesional epidermis. Staining for Bax was evident in the cells of the perilesional uninvolved skin, but decreased in the epidermal cells of lesional involved skin. CONCLUSIONS: The decrease or absence of Bcl-2 and Bcl-x and the imbalance of Bax in the epithelial cells of affected DD skin is likely to be an important control point determined by the genetic mutation of SERCA2, which modifies the programme of the antiapoptotic proteins. The consequent imbalance of the factors controlling apoptosis in keratinocytes underlines another apoptotic pathway responsible for the dyskeratotic cells in DD.     

角质形成细胞生长因子及神经细胞生长因子在银屑病患者皮损中的表达

目的 探讨角质形成细胞生长因子(KGF)及神经细胞生长因子(NGF)与银屑病的关系及银屑病皮损中间质细胞与角质形成细胞的相互作用。方法 应用免疫组化技术分别检测33例银屑病患者皮损、8例非皮损和13例正常人皮肤中KGF、KGF受体、NGF、NGF受体的表达。结果 KGF、KGF受体在银屑病患者基底层和棘细胞下层有极强的表达,与非皮损组及正常对照组间差异有显着性(P<0.05),而非皮损组与正常对照组间差异无显着性(P>0.05).KGF、KGF受体在真皮层未见表达。NGF、NGF受体则主要表达在颗粒层和棘细胞上层,皮损组与非皮损组之间及非皮损组与正常组之间均差异有显着性(P<0.05)。结论 银屑病患者皮损中KGF及NGF可能介导了角质形成细胞的增殖与分化不全;银屑病皮损中存在着间质细胞和角质形成细胞相互作用的紊乱。     

Apoptosis, P53 and Bcl-2 expression in response to topical calcipotriol therapy for psoriasis

BACKGROUND: The histopathologic changes characteristic of psoriasis might be related to suppressed apoptosis. The P53 and Bcl-2 proteins play a central role in the regulation of apoptosis. This study aimed to evaluate P53 and Bcl-2 expression and apoptotic cells in the psoriatic skin before and after topical calcipotriol therapy. METHODS: Skin biopsies were obtained from nonlesional and lesional skin of 10 patients with generalized plaque psoriasis before and after treatment with topical calcipotriol ointment. The P53 and Bcl-2 expression was evaluated using immunoperoxidase technique and apoptotic cells by the terminal deoxynucleotide transferase (TdT) mediated deoxyuridine triphosphate nick end labeling (TUNEL) method. RESULTS: After topical calcipotriol therapy, keratinocytes of psoriatic skin showed significant decrease of P53 (P = 0.002) and increase of Bcl-2 (P = 0.01) expression. On the other hand lymphocytes showed significant decrease of Bcl-2 (P = 0.01). There were no apoptotic cells before treatment but after calcipotriol therapy, apoptosis was more detectable in keratinocytes than in lymphocytes. CONCLUSIONS: The results of the study suggested that one of the actions of calcipotriol in psoriasis might be exerted through induction of apoptosis, especially of keratinocytes, through a P53-independent pathway. Meanwhile, suppression of Bcl-2 expression in lymphocytes may promote apoptosis of dermal lymphocytes leading to healing of psoriasis.