β溶血性链球菌诱发点滴状银屑病发病机制的探讨

应用MTT方法检测急性点滴状银屑病患者外周血单核细胞(PBMC)对链球菌抗原的反应,用H-TdR掺入法和免疫组化法检测链球菌抗原刺激的PBMC培养上清液对人角质形成细胞株COLO-16DNA合成以及HLA-DR、ICAM-1分子表达的影响探讨β型链球菌诱发急性点滴状银屑病的发病机制。结果:急性点滴状银屑病患者PBMC对链球菌抗原的反应较对照组更为明显(P<0.01),其中24h链球菌抗原刺激的PBMC培养上清液对角质形成细胞的促增殖作用较对照组显著增强(P<0.01),并能诱导角质形成细胞表达HLA-DR和ICAM-1。具有银屑病素质的个体体内可能存在链球菌抗原特异性T淋巴细胞,受链球菌抗原或超抗原作用后增殖,产生大量细胞因子,导致角质形成过度增生和HLA-DR、ICAM-1异常表达。     

链球菌抗原刺激的银屑病患者外周血单一核细胞培养上清液中TNF－α和IL－6的检测

以往的研究表明 [1],银屑病患者外周血单一核细胞 (PBMC)对链球菌抗原刺激反应明显 ;而且 ,链球菌抗原刺激 PBMC的培养上清液可促进人角质形成细胞 DNA合成和细胞间粘附因子 1(ICMA－ 1)、 HLA－ DR分子表达。说明培养上清液中的细胞因子发生了质或量的变化。为此,我们进一步检测了银屑病患者链球菌抗原刺激的 PBMC培养上清液中肿瘤坏死因子α（ TNF－α）和白介素 6（ IL－ 6）变化。期望有助于探讨银屑病的发病机制。 一、材料和方法 （一）临床资料：临床和病理确诊的点滴状银屑病患者 7例、斑块状 5例;健康对照 8例。点…     

β溶血型链球菌诱发点滴型银屑病发病机制的研究

目的 探讨β溶血型链球菌所诱发的急性点滴型银屑病的发病机制.方法 应用MTT方法观察急性点滴型银屑病患者外周血淋巴细胞(PBMC)对链球菌抗原的反应,用³H-TdR掺入法和免疫组织化学方法检测链球菌抗原刺激的PBMC培养上清液对人类角质形成细胞株COLO16DNA合成以及HLA-DR、ICAM-1分子表达的影响.结果 急性点滴型银屑病患者PBMC对链球菌抗原的反应较对照组更为明显(P<0.01),其24h链球菌抗原刺激的PBMC培养上清液对角质形成细胞的促增殖作用较对照组显着增强(P<0.01),并能诱导角质形成细胞表达HLA-DR和ICAM-1.结论具有银屑病素质的个体体内可能存在链球菌抗原特异性的T淋巴细胞,受链球菌抗原或超抗原作用后增殖,产生大量细胞因子,导致角质形成细胞过度增生和HLA-DR、ICAM-1异常表达.     

葡萄球菌性超抗原对银屑病患者外周血淋巴细胞产生白介素-2、γ-干扰素的影响

银屑病患者外周血淋巴细胞对葡萄球菌性超抗原（葡萄球菌肠毒素B，SEB)和链球菌超抗原刺激反应增强，且经SEB刺激的银屑病患者外周血淋巴细胞(PBLC)培养上清液可促进角质形成细胞增殖，表达HLA-DR和Fas抗原，继而诱导细胞凋亡。为了进一步探讨培养上清液对角质形成细胞的作用机制，笔者检测了SEB刺激前后的银屑病患者淋巴细胞培养上清液中白介素(IL）-2、γ-干扰素（IFN-γ)的水平变化，现将结果报告如下。     

β-溶血型链球菌诱发银屑病发病机理探讨

探讨β-溶血性链球菌诱发银屑病的机制。采用3H-TdR掺入法测定细胞增殖反应,AnnexinV法测定细胞凋亡,流式细胞仪检测细胞表面抗原表达。结果显示β-溶血性链球菌(SP)刺激淋巴细胞活化增殖,经SP活化的淋巴细胞培养上清液作用于角质形成细胞48h,可促进角质形成细胞增殖,诱导角质形成细胞表达HLA-DR和Fas抗原;再次加入上清液继续作用48h,则诱导角质形成细胞凋亡。SP作为超抗原首先活化T细胞,使之释放细胞因子,后者使角质形成细胞活化增殖,表达和抗原,继而诱导细胞凋亡,此过程可能是银屑病的主要发病机制之一。     

银屑病患者皮损局部朗格汉斯细胞数量异常机制的研究

目的：探讨银屑病患者皮损局部朗格汉斯细胞(LCs)数量异常的原因。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对单核细胞的趋化功能；通过酶联免疫吸附法(ELISA)检测上清液中单核细胞趋化蛋白—1(MCP-1)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单核细胞的趋化能力明显强于正常对照组；其分泌的MCP-1水平也高于正常人。结论：银屑病角质形成细胞表达的趋化因子趋化了更多数量的单核细胞至皮损局部，因此，银屑病患者皮损局部LCs的数量理应是增多的。但由于银屑病角质形成细胞表达的其它一些因子也促使了单核细胞衍生的LCs的活化，活化的LCs会迁移至淋巴结或活化后凋亡，又导致其数量减少。因此，银屑病患者皮损局部朗格汉斯细胞数量是一动态变化过程。     

银屑病患者淋巴细胞与角质形成细胞体外培养NF-κB的表达

目的：探讨银屑病发病中淋巴细胞和角质形成细胞的相互作用及核因子调控机制。方法：从银屑病患者外周血分离单一核细胞（PBMC）．正常人皮肤体外培养获角质形成细胞（KC），两者混合培养，利用流式细胞仪分析培养体系及PBMC、KC各自的转录因子NF-κB表达，ELISA法测上清液中IL-8、ICAM—I含量。结果：银屑病患者培养体系及PBMC、KC中NF—κB和细胞因子的表达水平均高于健康对照组（P〈0．01）。结论：银屑病患者中NF—κB的活化增强是其发病的重要因素，同时提示抑制NF—κB活性的药物可能有助于银屑病的治疗。     

维A酸对角质形成细胞NF-кB及细胞因子的影响

目的探讨维A酸药物对角质形成细胞的影响及核因子调控机制,为药物治疗银屑病提供理论依据。方法从银屑病患者外周血分离单一核细胞(PBMCs),与角质形成细胞系HaCat混合培养,用维A酸预处理HaCat细胞,以雷公藤为对照,利用流式细胞仪分析培养体系及HaCat各自的NFкB表达,ELISA测上清液中IL8、ICAM1含量。结果银屑病患者培养体系及HaCat中NFкB和细胞因子的水平均高于健康对照组(P<0.01),经维A酸预处理HaCat后,可抑制核因子的表达,与雷公藤比较差异无显著性。结论维A酸可能通过下调NFкB的活化而改善银屑病的症状,同时提示抑制NFкB活性的药物可能有助于银屑病的治疗。     

RANTES在银屑病患者角质形成细胞中的表达及其作用

目的：探讨银屑病皮损局部T淋巴细胞高度浸润的原因，并分析了趋化因子RANTES在此过程中的作用。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对T淋巴细胞的趋化功能；通过酶联免疫吸附(ELISA)法检测上清液中RANTES的表达。结果：银屑病皮损处角质形成细胞培养上清液对T淋巴细胞的趋化能力明显强于正常对照组；其分泌的RANTES水平也高于正常人。结论：银屑病患者皮损局部T淋巴细胞的大量浸润，部分是由于角质形成细胞具有较强的趋化T淋巴细胞能力，而银屑病角质形成细胞中高表达的RANTES可能是发挥此作用趋化因子之一。     

他扎罗汀抑制角质形成细胞血管内皮生长因子的表达

目的　探讨他扎罗汀治疗银屑病等的作用机制。方法　用免疫组化方法检测他扎罗汀对培养的角质形成细胞血管内皮生长因子 (VEGF)表达的影响 ,用双抗体夹心ELISA法定量检测他扎罗汀对培养的角质形成细胞上清液中VEGF分泌的影响。结果　免疫组化染色表明他扎罗汀可以减少培养的角质形成细胞VEGF的产生 ,表现为角质形成细胞染色强度明显减弱。角质形成细胞培养上清液检测表明 ,他扎罗汀可明显减低角质形成细胞VEGF的分泌 ,并呈剂量依赖性 ,10 -8mol/L他扎罗汀即可使角质形成细胞VEGF分泌减少 40 %左右 (P <0 .0 1)。结论　他扎罗汀治疗银屑病的机制之一可能在于减少银屑病病人角质形成细胞VEGF分泌 ,从而改善银屑病皮损的血管扩张、增生等病理改变 ,进而减轻炎症细胞浸润及炎症反应。     

金黄色葡萄球菌性超抗原诱发银屑病发病机理探讨

目的探讨金黄色葡萄球菌性超抗原诱发银屑病的机制。方法3H-TdR掺入法测定细胞增殖反应,亚二倍体细胞含量测定,片段化DNA分析,膜联蛋白V(AnnexinV)法测定细胞凋亡,流式细胞仪检测细胞表面抗原表达。结果金黄色葡萄球菌肠毒素B活化的淋巴细胞培养上清液作用于角质形成细胞48h,可促进角质形成细胞增殖,诱导角质形成细胞表达HLA-DR和Fas抗原;再次加入上清液继续作用48h,则诱导角质形成细胞凋亡（P<0.01）。结论金黄色葡萄球菌肠毒素B作为超抗原活化T细胞,使之释放细胞因子,后者使角质形成细胞首先活化增殖,继而凋亡。     

Decreased IL-10 production by psoriatic peripheral blood mononuclear cells stimulated with streptococcal superantigen

The strong association of acute guttate psoriasis and streptococcal throat infection has suggested a role for streptococcal antigens in the pathogenesis of psoriasis. We have reported that psoriatic peripheral blood mononuclear cells (PBMCs) showed significantly lower responses to cytoplasmic membrane-associated protein (CAP) isolated from group A beta-hemolytic streptococci, a kind of streptococcal superantigen. The objectives were to evaluate the abnormal cytokine production by psoriatic PBMCs to streptococcal superantigen, CAP. We compared the production of four different cytokines, i.e. IL-4, IL-5, IL-10, and IFN-gamma, by PBMCs between psoriatic patients and healthy controls after stimulation with CAP or two different staphylococcal superantigens, staphylococcal enterotoxin A (SEA) or E (SEE). When PBMCs were stimulated with CAP, the production of IL-10 was significantly lower by psoriatic PBMCs than by those from healthy controls, whereas those of IL-4, IL-5, or IFN-gamma were not different between the two groups. Such a significant decrease in IL-10 production by psoriatic PBMCs was not observed when they were stimulated with staphylococcal superantigens. Flow cytometric analysis of intracytoplasmic IL-10 demonstrated defective IL-10 production by psoriatic PBMCs in both CD3+ T cells and CD14+ monocytes. There was a significant positive correlation between IFN-gamma production by PBMCs and the proliferation of Vbeta8+ T cells preferentially stimulated by CAP. These data demonstrating the defective IL-10 production by psoriatic PBMCs stimulated with streptococcal superantigen seem to explain why only psoriatic patients evolve sustained and Th-1 deviated skin lesions after streptococcal upper respiratory infection.     

Psoriatic lesional keratinocytes promote the maturation of human monocyte-derived Langerhans cells

BACKGROUND: Langerhans cells (LCs) are important antigen-presenting cells in the epidermis and may play a key role in the pathogenesis of psoriasis. It has been proven that LCs isolated from psoriatic lesions are abnormal. However, the mechanism of the abnormality has not been reported so far. OBJECTIVE: In the present study, we investigated the effect of psoriatic lesional keratinocytes on the maturation of LCs. METHODS: Monocytes isolated from healthy peripheral blood could differentiate into LCs in the presence of granulocyte-macrophage colony-stimulating factor, interleukin (IL) 4 and transforming growth factor beta1 for 5 days. Then, human monocyte-derived LCs were cultured with supernatants from psoriatic lesional keratinocytes for another 2 days. Their phenotypes and phagocytic capacity were analyzed by flow cytometry. IL-12 secreted by LCs was determined by ELISA. RESULTS: Supernatants from psoriatic lesional keratinocytes could up-regulate the expression of HLA-DR and CD86 on LCs more significantly than supernatants from healthy keratinocytes, but less powerfully than lipopolysaccharide. The levels of IL-12 secreted by LCs also increased. In contrast, the expression of CD1a on LCs and their phagocytic capacity were reduced. CONCLUSION: Human monocyte-derived LCs cultured with supernatants from psoriatic lesional keratinocytes displayed the characteristics of maturation. This suggests that psoriatic lesional keratinocytes might secrete some factors that could promote the maturation of LCs, which may play important roles in immune reactions related to psoriasis.     

β-溶血型链球菌与角质形成细胞增殖和凋亡研究

目的 探讨β－溶血型链球菌诱发银屑病的机制。方法 ＾３Ｈ－ＴｄＲ掺入法、流式细胞仪测定亚二倍体含量、片段化ＮＤＡ分析、ＡｎｎｅｘｉｎＶ凋亡检测法。结果 链球菌悬液活化的外周血细胞培养上清液作用于角质形成细胞４８ｈ，可促进角质形成细胞增殖，再次加入上清液继续作用４８ｈ，则诱则细胞凋亡（Ｐ〈０．０１）；而链球菌本身对角质形成细胞增殖或凋亡无明显影响。结论 链球菌作为超抗原活化Ｔ细胞，使之释放细胞因子而     

Characterization of intercellular adhesion molecule-1 and HLA-DR expression in normal and inflamed skin: modulation by recombinant gamma interferon and tumor necrosis factor

Lymphocytes bind to cultured keratinocytes that are treated with interferon gamma (IFN-gamma) and tumor necrosis factor (TNF). When the lymphocytes are preincubated with antibody to lymphocyte function associated antigen-1 (LFA-1), this adherence is inhibited. Because intercellular adhesion molecule-1 (ICAM-1) is a ligand for LFA-1, we studied the cellular expression of ICAM-1, as well as two other IFN-gamma-inducible antigens, (HLA) human lymphocyte antigens DR and DQ, in both normal and diseased skin. The modulation of these cell surface antigens by IFN-gamma and TNF with the use of short-term organ cultures of skin was compared with isolated keratinocytes grown in a conventional tissue culture system. While in normal skin, keratinocytes did not express HLA-DR, DQ, or ICAM-1, when organ cultures were supplemented with IFN-gamma, rapid induction of keratinocyte ICAM-1 expression occurred after 24 hours; HLA-DR but not DQ expression occurred after 48 hours. TNF also induced keratinocyte ICAM-1 expression (although to a lesser degree than IFN-gamma) but did not induce either keratinocyte HLA-DR or DQ expression. There was good correlation of keratinocyte expression of ICAM-1 and HLA-DR by IFN-gamma and TNF when the epidermis of the organ culture system was compared with the isolated keratinocytes grown in tissue culture. The presence of intraepidermal lymphocytes correlated extremely well with keratinocyte ICAM-1 expression but not with keratinocyte HLA-DR expression in psoriasis, atopic dermatitis, lichen planus, and mycosis fungoides. The intensity of endothelial cell expression of ICAM-1 correlated with the degree of dermal inflammation. We conclude that IFN-gamma, once produced by activated T lymphocytes in the dermis, may be of importance in lymphocyte trafficking in the epidermis by the induction of keratinocyte ICAM-1 expression. The use of the short-term organ culture system, in which there is inducible ICAM-1 expression, provides an experimental bridge between purely in vitro and in vivo investigations to further our understanding of the molecular basis for lymphocyte apposition to keratinocytes in the skin.     

Autoantibodies to autologous skin in guttate and plaque forms of psoriasis and cross-reaction of skin antigens with streptococcal antigens

Background Psoriasis is a chronic disease of the skin that appears to be of autoimmune nature. It has a strong association with throat streptococcal infections, as well as with stressful events. Although many groups consider psoriasis to be a T-cell-mediated autoimmune disease, autoantibodies could also play a role in the development of this process. Methods In this work, we looked for autoantibodies to psoriatic skin in 21 psoriatic patients and four healthy donors (controls). The immunoperoxidase technique was used to look for autoantibodies in autologous sera in skin sections obtained from lesions or from healthy areas of the same patient, before and after immunoadsorption with a Streptococcus pyogenes extract. The skin biopsies were also analyzed with a pool of sera from mice immunized with the streptococcal extract. Results We found that all psoriatic patients had autoantibodies to antigens present in keratinocytes, whereas healthy subjects did not. These antibodies did not recognize epitopes on healthy skin from the same psoriatic patients or controls. Immunoadsorption of autologous sera removed the reactivity to antigens in skin lesions in all cases. Mouse anti-streptococcal sera recognized epidermal antigens present in lesional psoriatic skin, but not in healthy skin from psoriatic patients or controls. Deposits of immunoglobulin G (IgG) were not detected in the lesions. Conclusions It seems that autoantibodies, although they do not appear to participate in the pathogenesis of psoriasis, are an important feature, and that skin antigens, which appear in lesional immature keratinocytes, cross-react with S. pyogenes and contribute to the autoimmune process in psoriasis.     

云南汉族与链球菌感染有关的银屑病患者HLA-DR易感基因研究

目的：发现云南汉族与链球菌感染相关的银屑病患者易感基因，探讨银屑病与感染和遗传的关系。方法：用多聚酶链反应技术及序列特异性引物（PCR-SSP），对36例咽部致病性链球菌培养阳性银屑病患者进行HLA-DR基因分型，并与28例云南汉族正常人HLA-DR分型结果比较。结果：银屑病患者HLA-DR7基因频率比正常人显著增高，HLA-DR15基因频率也增高；20例HLA-DR15阳性患者有19例与HLA-DR7连锁，而正常组无DR7与DR15连锁。结论：云南汉族与链球菌感染有关银屑病患者易感基因与HLA-DR7及DR15关联，推测这两个位点的等位基因连锁以共同对链球菌感染相关银屑病易感性发挥作用。     

Changes in T-cell phenotype and adhesion molecules expression in psoriatic lesions after low-dose cyclosporin therapy

Cyclosporin is a very effective treatment for severe psoriasis, but its exact mechanism of action in this disease is not completely understood. It has been hypothesized that the drug could act through (lie inhibition of the expression of certain cell adhesion molecules on the keratinocytes prior to the reduction in the number of epidermal inflammatory cells. Several studies have focused on ICAM-1 changes on keratinocytes and endothelial cells after cyclosporin treatment in psoriatic patients but their results have been somewhat contradictory. We examined changes in T-cell markers and adhesion molecules among keratinocytes, enclothelial and inflammatory cells after low-dose cyclosporin treatment for severe psoriasis. We performed a histological and immunohistochemical study on psoriatic skin among 10 patients (7 males and 3 females; mean age 37 years) treated with low-dose (2.5 mg/kg/day) cyclosporin, prior to therapy, after 1 month, and after 3 months of treatment. The mean PASI (Psoriasis Area and Severity Index) before treatment was 23±4, 13±7 after the first month of therapy, and 8±2 at the end of the third month of therapy. Pretherapy samples showed a moderate to severe inflammatory infiltrate mainly clue to T-lymphocytes expressing a T-cell memory (UCHL-1) and helper/inducer (CD4) phenotype. Most of these cells also expressed HLA-DR and LFA-1 and ICAM-1 antigens. Alter the treatment, an overall reduction in the degree of epidermal hyperplasia was seen (p=0.01). The severity of the infiltrate was clearly reduced (p=0.05), but no significant changes in the phenotype profile were observed. Although slightly reduced, endothelial ICAM-1 expression persisted after cyclosporin therapy. Keratinocyte ICAM-1 expression was uniformly and significantly reduced after 1 month and 3 months of therapy (p=0.01). These results support the hypothesis that cyclosporin interferes with the expression of keratinocyte adhesion molecules in patients with psoriasis.