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。     

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     

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。     

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.     

皮肤科学基础

２００１０６６３β－溶血型链球菌与角质形成细胞增殖和凋亡研究／张峻岭（天津长征医院皮肤科）…／／中国皮肤性病学杂志．－２０００，１４（５）．－３０２～３０４ 为探讨β－溶血型链球菌诱发银屑病的机制，应用３Ｈ－ＴｄＲ掺入法测定角质形成细胞增殖反应，以流式细胞仪测定亚二倍体含量．行ＤＮＡ片段化分析，再应用 Ａｎｎｅｘｉｎ Ｖ法测定磷脂酰丝氨酸（ＰＳ）“膜外化”细胞含量，观察细胞凋亡的早期表现。结果链球菌抗原悬液（ＳＰ）活化的Ｔ淋巴细胞上清液作用于角质形成细胞的Ｃｏｌｏ－１６细胞４８ｈ后，细胞的刺激指数…     

链球菌抗原刺激的银屑病外周血单个核细胞培养上清液对角质形成细胞的作用

目的 了解链球菌抗原刺激的银屑病外周血单个核细胞(PBMCs)培养上清液对角质形成细胞的作用以探讨链球菌感染后的银屑病的发病机制。方法 ^3H—TdR掺入法检测PBMCs培养上清液对角质形成细胞DNA合成的影响；免疫组织化学方法检测细胞间教附因子1(ICAM—1)和人类白细胞抗原DR分子(HLA—DR)表达。结果 银屑病患者链球菌抗原刺激的PBMCs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，并能诱导角质形成细胞表达HLIA—DR和ICAM—1分子。结论 受链球菌抗原刺激的银屑病PBMCs培养上清液可促进角质形成细胞增殖和活化，可能是链球菌感染之后银屑病发病的重要原因。     

超抗原对银屑病患者外周血单一核细胞和Colo 16细胞株的细胞动力学影响

目的:探讨超抗原在银屑病发病中的作用。方法:采用四甲基偶氮唑盐(MTT)方法和酶联免疫吸附试验(ELISA),检测进行期寻常型银屑病患者和正常对照外周血单一核细胞(PBMC)和角质形成细胞Colo 16细胞株经葡萄球菌肠毒素B(SEB)体外刺激48 h的细胞增殖和凋亡。结果:进行期寻常型银屑病患者和正常人PBMC经SEB刺激,其细胞增殖和凋亡与空白组比较差异有显著性(P<0.01);角质形成细胞(Colo 16细胞株经SEB刺激,其细胞增殖和凋亡与空白组比较差异无显著性(P>0.05)。结论:超抗原可能是通过刺激PBMC的活化,引发银屑病皮损的发生,而对角质形成细胞没有直接作用。超抗原活化的PBMC迅速进入凋亡,提示超抗原刺激PBMC活化增殖和凋亡是自身稳定的调控,使PBMC数量和质量恢复正常。     

银屑病患者淋巴细胞对葡萄球菌和链球菌超抗原刺激的增殖反应

银屑病与细菌性超抗原的相关性日益引起医学界关注,大量资料表明细菌感染可诱发银屑病,50%银屑病患者皮肤寄居金黄色葡萄球菌,上呼吸道β-溶血性链球菌感染与点滴状银屑病发病及斑块状银屑病症状加重有关^[1].但具体发病机理不甚明确,国内外研究甚少.因为葡萄球菌和β溶血性链球菌产生的毒素具有超抗原特性,而超抗原能选择性激活大量T淋巴细胞,因此,我们采用3HTdR掺入法观察比较银屑病和正常人外周血淋巴细胞(PBLC)对葡萄球菌肠毒素B(SEB)和链球菌裂解悬液(SP)刺激的增殖反应,以普通抗原破伤风类毒素(TT)作对照.     

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。     

依曲替酸(R_O10-1670)对培养的正常人角质形成细胞Fas/Fasl系统表达及凋亡的研究

目的　通过研究依曲替酸作用于培养的正常人KC前后Fas/Fasl的表达及其与凋亡的关系 ,进一步探讨其治疗银屑病的作用机理。方法　依曲替酸作用培养的正常人KC后 ,进行免疫细胞化学研究 ,观察其对KC表达Fas/Fasl蛋白的影响。用流式细胞仪 (FACS)对依曲替酸处理后的KC进行凋亡检测。结果　①正常人KC几乎不表达Fas和Fasl ;②依曲替酸作用 16h时KC的Fasl表达最强 ,40h时表达Fas最强 ;相同条件下 ,KC表达Fasl比Fas弱 ;③依曲替酸刺激后引起KC凋亡。结论　培养的正常人KC中Fas/Fasl系统不参与其凋亡 ;依曲替酸作用于培养的正常人KC后 ,上调Fas/Fasl系统表达 ,并促进KC凋亡 ,拮抗KC良性增生 ,Fas/Fasl介导的凋亡可能是维甲酸治疗银屑病的重要原因。     

银屑病患者皮损中细胞凋亡情况的评价

目的 探讨细胞恨与银屑病的关系。方法 用免疫组化ＳＰ法检测银屑病皮损与非皮损中Ｂａｘ、Ｆａｓ、Ｆａｓ－１的表达,并用ＴＵＮＥＬ（末端脱氧核苷酰转移介导的ｄ－ＵＴＰ－生物素缺口本端标记）技术检测细胞凋亡情况。结果 与正常人相比,银屑病表皮角质形成细胞,真皮炎症细胞及炎症细胞及血管内皮均存在不同程度的上述蛋白的过度表达,伴细胞凋亡增多,部分在治疗后末完全恢复正常。结论 推测银屑病皮损中角质形成对细胞过     

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     

砷化物抑制银屑病角质形成细胞增殖的研究

银屑病主要表现为角质形成细胞过度增殖及凋亡异常,其中角质形成细胞过度增殖是由于细胞凋亡功能障碍或失调所致,凋亡缺陷在银屑病的发病机制巾发挥着重要作用。研究表明,砷化物可以通过对Fas/Fas配体、端粒和端粒酶的影响以及联合阻断JNK等多种途径诱导角质形成细胞凋亡,从而抑制其过度增殖。因此,砷化物有望成为一种局部治疗银屑病的新型药物。     

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.     

存活素反义寡核苷酸对角质形成细胞增殖和凋亡的影响

目的探讨存活素反义寡核苷酸对角质形成细胞增殖和凋亡的影响。方法以脂质体介导存活素反义寡核苷酸转染体外培养的角质形成细胞。采用MTT方法观察存活素反义寡核苷酸对角质形成细胞生长曲线的影响;采用RT-PCR方法观察存活素反义寡核苷酸对角质形成细胞存活素表达水平的影响;采用流式细胞仪检测存活素反义寡核苷酸对角质形成细胞细胞周期和凋亡的影响。结果存活素反义寡核苷酸作用于角质形成细胞后,细胞增殖受到明显抑制,存活素mRNA表达水平明显下降,细胞出现明显的凋亡现象。结论存活素反义寡核苷核酸能够抑制角质形成细胞增殖,促进角质形成细胞凋亡。提示存活素可能会成为一个新的治疗银屑病的靶分子。     

Human epidermal cells synthesize HLA-DR alloantigens in vitro upon stimulation with gamma-interferon

Under certain pathologic conditions, human keratinocytes synthesize and express HLA-DR antigens. Assuming that soluble mediators might be responsible for this phenomenon, differentiating, primarily DR-keratinocytes were grown in the presence or absence of mixed leukocyte culture supernatants and tested for Ia antigen expression. After 6 days of culture, keratinocytes displayed surface-bound HLA-DR alpha/beta complexes when exposed to mixed leukocyte culture supernatants but not when cultured in media alone. These HLA-DR moieties on keratinocytes result from active biosynthesis as evidenced by the demonstration of the intracytoplasmic HLA-DR gamma (invariant) chain within these cells. In view of reports that interferon-gamma promotes Ia-production in a variety of cell types, we reasoned that this lymphokine might be responsible for the Ia-inducing property of mixed lymphocyte culture supernatants. Indeed, recombinant interferon-gamma, but not interferon-alpha or interleukin-2, proved to be a potent stimulator of Ia expression by keratinocytes. The further finding that this event can be prevented by the addition of a monoclonal anti-interferon-gamma antibody strongly suggests that this cytokine is directly responsible for HLA-DR production by keratinocytes. The interferon-gamma-induced acquisition of HLA-DR antigens by primarily DR-keratinocytes may provide a useful tool to study the role of these alloantigens in T-cell activation and may also add to our understanding of mechanisms operative in epidermal cell-T-cell interactions.