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51.
Immunolocalization of extracellular matrix proteins and integrins in sarcoid lymph nodes 总被引:1,自引:0,他引:1
K. Shigehara Noriharu Shijubo Michio Hirasawa Shosaku Abe Toshimitsu Uede 《Virchows Archiv : an international journal of pathology》1998,433(1):55-61
To improve our understanding of the role of extracellular matrix (ECM) proteins and integrins during the processes of granuloma
formation in sarcoidosis, we examined the distribution of ECM proteins and the expression of integrins in sarcoid lymph nodes
by immunohistochemical methods. We also examined the expression of transforming growth factor-β1 (TGF-β1), which is one of
major regulators for synthesis of ECM proteins. Most ECM proteins were detected in the periphery of the granulomas in a concentric
pattern, and fibronectin was diffusely detected from an early to a regressive stage. Compared with normal lymph nodes, most
β1-integrin subfamilies (α1, α4, α5 and α6) were more strongly expressed on lymphocytes around the granulomas. Epithelioid
cells exhibited strong expression of the α5 molecule. Fibroblasts exhibited the expression of the α2 and α5 molecules surrounding
ECM proteins. The α5β1 molecule had a distribution similar to that of fibronectin. TGF-β1 was detected in epithelioid cells
throughout the various evolutional stages and its expression was especially marked in mature granulomas. Interaction of fibronectin
and the α5β1 molecule may have an important role in the process of formation of sarcoid granuloma. The expression of TGF-β1
may be involved in the regression of sarcoid granuloma by initiating fibrosis and atrophy of epithelioid cells.
Received: 2 December 1997 / Accepted: 19 February 1998 相似文献
52.
激发型4-1BB单抗联合凋亡肿瘤细胞负载的树突状细胞在恶性肿瘤免疫治疗中的作用 总被引:2,自引:0,他引:2
目的:研究激发型4-1BB单抗(2A)联合凋亡肿瘤细胞负载的DC(AP-DC)疫苗在小鼠B细胞淋巴瘤免疫治疗中的作用.方法:凋亡小鼠B细胞淋巴瘤细胞A20负载的DC用来制备AP-DC.A20荷瘤小鼠分别被注射AP-DC、2A单抗或二者联合.观察肿瘤生长情况及小鼠生存期.流式细胞术检测免疫治疗后荷瘤鼠脾脏T细胞的表型和胞浆内细胞因子;3H-TdR掺入试验检测T细胞体外增殖能力;ELISA法检测荷瘤鼠血清和脾脏T细胞培养上清中IL-2、IFN-γ和IL-10含量.结果:应用激发型4-1BB单抗2A或AP-DC疫苗对荷瘤小鼠开展免疫治疗,可抑制肿瘤生长,延长荷瘤鼠生存期,获得12.5%或25%的肿瘤完全缓解率.但二者联合应用,治疗效果更好,可获得62.5%的肿瘤完全缓解率,并且荷瘤鼠可长期生存.联合治疗后荷瘤鼠脾脏T细胞体外增殖更为显著,CD4^+IFN-γ^+细胞的比例也明显增加.IL-2和IFN-γ的分泌水平在联合治疗荷瘤鼠的血清和脾脏T细胞的培养上清中升高更明显,而IL-10的分泌则降低.结论:激发型4-1BB单抗和AP-DC在肿瘤免疫治疗中有协同作用. 相似文献
53.
目的 观察血小板内皮细胞黏附分子-1(PECAM-1)在大鼠结肠癌组织及淋巴管的表达.探讨其与肿瘤细胞淋巴道转移之间的关系.方法 构建大鼠结肠癌动物模型,运用免疫组织化学方法检测PECAM-1在结肠癌组织及淋巴管的表达.结果 PECAM-1在正常大鼠结肠组织表达于血管和淋巴管内皮,在肿瘤组织表达于腺体、血管和淋巴管的内皮,其中在肿瘤腺体的表达早期多位于细胞膜上,中晚期则转移至细胞质内,且表达随肿瘤进展而下降.在肿瘤淋巴管内皮的表达随肿瘤进展而下降,在血管内皮表达不变.结论 PECAM-1可能介导大鼠结肠癌早期肿瘤细胞与内皮之间的黏附;PECAM-1在大鼠结肠癌淋巴管的表达降低可能与肿瘤内淋巴管新生及内皮连接开放相关. 相似文献
54.
A fucose-containing epitope potentially involved in gamete interaction on the human zona pellucida 总被引:2,自引:1,他引:2
Lucas H.; Bercegeay S.; Pendu J.Le; Jean M.; Mirallie S.; Barriere P. 《Human reproduction (Oxford, England)》1994,9(8):1532-1538
The oligosaccharide moiety of human, porcine and bovine zonaepellucidae was studied with lectins and monoclonal antibodiesspecific for tri- or tetra-saccharidic epitopes containing atleast one terminal -L-fucose. Animal eggs were collected fromfollicular aspirates, human eggs were collected from in-vitrofertilization and embryo transfer programmes and pooled intosix groups. By direct immunofluorescence, the lectins reactivitywas detected for the animal or the human zonae pools in thesame way. Reactivity of Aleuria aurantia lectin demonstratedthe presence of L-fucose terminal residues in the zonaefrom the three species studied. By indirect immunofluorescence,the 225 antibody reactivity was detected in every poolof human zonae whereas there was no evidence of any antibodyreactivity on animal zonae. Using an anti-Lewis-b blood groupantibody (225), we observed expression of this antigenas an intrinsic component of the human zona pellucida, independentlyof patients'Lewis red blood cell phenotypes. Antibody 225inhibited the spermatozoa-zona binding in a hemizonaassay, suggesting that this fucose-containing antigen couldbe part of a sperm-zona receptor. 相似文献
55.
Noriko Toyama-Sorimachi Kensuke Miyake Masayuki Miyasaka 《European journal of immunology》1993,23(2):439-446
We have established an endothelial cell line KOP2.16 from pooled mouse lymph nodes. Resting lymphocytes avidly bound to KOP2.16 and migrated underneath the cytoplasm. The binding was partly mediated by VLA-4 and VCAM-1, but apparently independent of CD44 since anti-CD44 antibody examined failed to inhibit the binding. However, pretreatment of lymphocytes with anti-CD44 resulted in the rapid appearance of Ca2+-, Mg2+-independent, LFA-1/ICAM-1-, CD2/LFA-3,VLA-4/VCAM-l-independent lymphocyte binding, indicating that a novel adhesion pathway was induced by the anti-CD44 treatment. Interestingly, the elicited adhesion was observed only when anti-CD44 that block hyaluronate recognition of CD44 were used for lymphocyte pretreatment. Neither hyaluronate itself nor non-blocking anti-CD44 up-regulated the adhesion. Fab fragment of the blocking anti-CD44 did not induce the up-regulation unless cross-linked with a second antibody, indicating that cross-linking of surface CD44 is necessary for induction of a novel adhesion pathway. We propose that the agonistic anti-CD44 antibodies induce a novel adhesion pathway by mimicking ligand binding to CD44 on the lymphocyte surface and that non-hyaluronate ligand(s) is involved in regulation of adhesive function of CD44. Potential involvement of such a regulatory mechanism in lymphocyte homing is discussed. 相似文献
56.
雷公藤红素对人肥大细胞系粘附能力和粘附分子表达的影响 总被引:4,自引:0,他引:4
雷公藤红素是雷公藤单体之一.本文研究雷公藤红素对人肥大细胞系HMC-1细胞粘附及粘附分子表达的影响.结果发现:HMC-1细胞能自发地表达β1、β3型整合素和CD44,不表达β2型整合素,具有迅速粘附于鼠尾胶的能力,在粘附过程中细胞由圆形、椭圆形变成梭形、多极形.雷公藤红素与HMC-1细胞在粘附前或粘附后共育均能以剂量和时间依赖方式抑制粘附和粘附过程中细胞形态的变化,并可下调粘附分子的表达.提示:雷公藤红素能抑制HMC-1细胞的粘附,这一作用与其抑制粘附分子表达和细胞形态的改变有关. 相似文献
57.
本文介绍了在立体定向放射神经外科中,根据病人配戴头环和CT定标架作CT扫描所得的CT断层图像或配戴AVM定位箱做血管造影得到的两张X光片确定病人颅内病灶的三维坐标的方法。 相似文献
58.
BACKGROUND: Clinically effective allergen-specific immunotherapy correlates with decreased circulating allergen-specific IL-4+ T cells but increased IFN-gamma+ cells at sites of allergen challenge. Whether immunotherapy promotes trafficking of IFN-gamma+ T cells to peripheral tissues is unknown. As aeroallergen is administered at higher concentrations during immunotherapy than those encountered naturally, the effect of allergen concentration on adhesion molecule (CD62L and CD49d) and chemokine receptor (CCR3 and CCR5) expression by peripheral-blood T cells was analysed in parallel with cytokine production. METHODS: House dust mite-allergic donor peripheral blood mononuclear cells were cultured for 14 days with different allergen concentrations. Cytokine profiles of were analysed by flow cytometry. RESULTS: Cultures stimulated with 100 microg/ml house dust mite extract compared with 1 microg/ml had increased proportions and numbers of CD62Llo, CD49dhi or CCR5+ T cells expressing IFN-gamma. CCR3-positive CD4+ and CD8+ T cell numbers were very low and did not differ between cultures. In contrast the proportions of 'peripheral tissue trafficking' CD4+ T cells expressing IL-4 were decreased in cultures stimulated with high in comparison with low allergen concentration. CONCLUSION: These results indicate the importance of achieving high allergen doses during immunotherapy to promote IFN-gamma production and expression of a 'peripheral tissue trafficking' phenotype by allergen-specific CD4+ and CD8+ T cells. The net change in cytokine milieu at sites of allergen encounter would then down-regulate clinical manifestations of allergic disease. 相似文献
59.
探讨血红素加氧酶1(heme oxygenase-1,HO-1)在器官移植中抗急性血管排斥反应的作用。通过建立豚鼠到SD大鼠异位心脏移植模型,用血红素(hemin)分别诱导供者和受者,上调HO-1基因表达;用眼镜蛇毒因子、环孢素A抑制超急性排斥反应;观测供者心脏存活时间,并分别检测心脏组织HO-1表达、受者血清异种抗体IgM的变化及异种抗体IgM和C3在血管内膜的沉积;采用TUNEL方法检测心脏组织细胞凋亡;RT-PCR方法测定组织CD40L mRNA表达水平。结果显示:上调HO-1表达能明显延长心脏移植存活时间,抑制异种抗体IgM表达和在血管内膜的沉积,减少心肌细胞的凋亡并且抑制CD40L mRNA的表达。该结论表明HO-1通过介导CD40-CD40L共刺激途径抑制大鼠异种心脏移植后急性血管排斥反应,延长心脏移植存活时间。 相似文献