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52.
Although many patients with SLE also have allergies, the immunological events triggering the onset and progression of the clinical manifestations of SLE by allergens have yet to be clarified. A total of three autoantigens, phosphoglycerate kinase 1 (PGK-1), triosephosphate isomerase (TIM) and enolase were identified by autologous serum in B cell lysate derived from HDM allergic SLE patients after Der p 2 stimulation. Autoantigen, TRIM-21 expression were also significantly increased in B cells derived from HDM allergic SLE patients. In PBMCs derived from SLE patients, the concentration of anti-PGK-1 was significantly upregulated after Der p 2 stimulation compared to HDM allergic without SLE patients and healthy subjects. Inflammatory related cytokines and chemokines include IL-1β, IL-6, IL-8, CXCL5 could be upregulated after Der p 2 stimulation in PBMCs derived from HDM allergic SLE patients. In conclusion, our data demonstrated that long-term allergen exposure could be a contributing factor in the development of SLE.  相似文献   
53.
Tolerogenic dendritic cells (tDC) constitute a promising therapy for autoimmune diseases, since they can anergize T lymphocytes recognizing self-antigens. Patients with type 1 diabetes mellitus (T1D) have autoreactive T cells against pancreatic islet antigens (insulin, glutamic acid decarboxylase 65 -GAD65-). We aimed to determine the ability of tDC derived from T1D patients to inactivate their insulin- and GAD65-reactive T cells. CD14 + monocytes and CD4 + CD45RA- effector/memory lymphocytes were isolated from 25 patients. Monocyte-derived DC were generated in the absence (control, cDC) or presence of IL-10 and TGF-β1 (tDC), and loaded with insulin or GAD65. DC were cultured with T lymphocytes (primary culture), and cell proliferation and cytokine secretion were determined. These lymphocytes were rechallenged with insulin-, GAD65- or candidin-pulsed cDC (secondary culture) to assess whether tDC rendered T cells hyporesponsive to further stimulation. In the primary cultures, tDC induced significant lower lymphocyte proliferation and IL-2 and IFN-γ secretion than cDC; in contrast, tDC induced higher IL-10 production. Lymphocytes from 60% of patients proliferated specifically against insulin or GAD65 (group 1), whereas 40% did not (group 2). Most patients from group 1 had controlled glycemia. The secondary cultures showed tolerance induction to insulin or GAD65 in 14 and 10 patients, respectively. A high percentage of these patients (70–80%) belonged to group 1. Importantly, tDC induced antigen-specific T-cell hyporesponsiveness, since the responses against unrelated antigens were unaffected. These results suggest that tDC therapy against multiple antigens might be useful in a subset of T1D patients.  相似文献   
54.
Zhang JJ  Ouyang T  Wan WH  Xu GW  Deng GR 《癌症》2007,26(1):44-47
背景与目的:检测肿瘤患者外周血中肿瘤相关标志物是当前肿瘤研究的热点之一,恶性肿瘤患者外周血中存在游离的肿瘤相关DNA已引起肿瘤学界的极大关注,人们曾在多种肿瘤患者血清中发现与原发肿瘤相同的DNA变异.本研究以APC(adenomatous polyposis coli)基因启动子甲基化作为肿瘤标志物,探讨乳腺癌患者外周血清中游离的肿瘤相关DNA与肿瘤组织及临床病理参数的相关性.方法:采用甲基化特异性PCR(methylation specific-PCR,MSP)方法,分别检测84例乳腺癌组织、癌旁正常腺体组织及外周血清中游离DNA APC基因启动子甲基化状况.结果:84例乳腺癌组织APC基因启动子甲基化频率为45.2%(38/84),相应外周血清中同样DNA变异阳性检出率为31.0%(26/84).外周血清中DNA甲基化变异与肿瘤组织的甲基化状况显著相关(r=0.977,P=0.002).检测外周血清中APC基因甲基化的敏感性为68.4%,特异性为97.8%.肿瘤组织及外周血清中游离DNA甲基化异常与临床分期、病理类型、肿块大小及受体状况无相关性(P>0.05).肿瘤组织未检测到甲基化患者的血清中及健康人血清中均未检测到该基因甲基化变异.结论:乳腺癌患者外周血清中肿瘤相关DNA甲基化与肿瘤组织中相同基因的变异显著相关.  相似文献   
55.
热休克蛋白(HSP)是一类在生物进化中高度保守、广泛存在于原核和真核生物中的蛋白质。大量资料表明,HSP作为分子伴侣,参与其它蛋白质的折叠、转运、合成等过程,并可与细胞内的其它蛋白质结合,参与细胞的抗损伤、修复和热耐受过程,某些热休克蛋白还具有佐剂效应,能够激活免疫应答反应,以往对于HSP70及其免疫治疗的研究较为广泛。近年来随着对热休克蛋白研究的不断深入,人们发现高分子量的HSP110因其强大的分子伴侣功能而具备独特的佐剂效应,因而被认为在瘤苗制备及抗肿瘤免疫中具有很大的应用前景。  相似文献   
56.
APC基因与肠息肉病的发生特别是家族性腺瘤性息肉病(familiar adenomatous poliposis,FAP)有密切关系,不同的多态/突变类型引起疾病的临床表现各异,而且最近研究提示APC基因某些突变形式与散发性结直肠息肉的产生也相关。本文对目前APC基因的结构、功能、多态性/突变以及与表型间关系、临床应用方面作一综述。  相似文献   
57.
王艳  李岩 《世界华人消化杂志》2007,15(19):2162-2166
目的: 探讨APC和p53基因突变在结直肠癌中的意义.方法:采用变性梯度凝胶电泳(DGGE), DNA测序法分析15例正常人和60例散发性结直肠癌标本的APC基因15外显子和p53基因第5, 7外显子的基因突变.结果: 在结直肠癌组检出14例APC和16例p53基因突变, 测序证实其中13/14例APC发生在突变集中区域;9/16例p53基因突变位于第5外显子, 7/16例p53基因突变位于第7外显子, 2例同时检出了APC基因和p53基因突变.结论:DGGE是一种快速、简便、高效、灵敏的突变检测技术. 同时也证明APC基因突变和p53基因突变均参与了结直肠癌的发生、发展过程.  相似文献   
58.
Basophils have long been neglected in immunological studies because they were regarded as only minor relatives of mast cells. However, recent advances in analytical tools for basophils have clarified the non-redundant roles of basophils in allergic inflammation. Basophils play crucial roles in both IgE-dependent and -independent allergic inflammation, through their migration to the site of inflammation and secretion of various mediators, including cytokines, chemokines, and proteases. Basophils are known to produce large amounts of IL-4 in response to various stimuli. Basophil-derived IL-4 has recently been shown to play versatile roles in allergic inflammation by acting on various cell types, including macrophages, innate lymphoid cells, fibroblasts, and endothelial cells. Basophil-derived serine proteases are also crucial for the aggravation of allergic inflammation. Moreover, recent reports suggest the roles of basophils in modulating adaptive immune responses, particularly in the induction of Th2 differentiation and enhancement of humoral memory responses. In this review, we will discuss recent advances in understanding the roles of basophils in allergic inflammation.  相似文献   
59.
Macrophage migration inhibitory factor promotes intestinal tumorigenesis   总被引:5,自引:0,他引:5  
BACKGROUND & AIMS: The cytokine macrophage migration inhibitory factor (MIF) is expressed throughout the human gastrointestinal tract. Recently, protumorigenic activity of MIF has been described in several cancer models. Therefore, we investigated the expression and function of MIF during the early stages of intestinal tumorigenesis. METHODS: MIF messenger RNA, protein, and tautomerase activity were measured in normal intestinal mucosa and adenomas from patients with sporadic colorectal adenomas and in the adenomatous polyposis coli (Apc)Min/+ mouse model of intestinal tumorigenesis. MIF function was investigated by using VACO-235 human colorectal adenoma cells in vitro and by testing the effect of genetic deletion of Mif on ApcMin/+ mouse intestinal tumorigenesis. RESULTS: MIF expression and tautomerase activity were increased in human and ApcMin/+ mouse intestinal adenomas compared with adjacent normal mucosa. Up-regulation of MIF occurred mainly in epithelial cells (associated with an increasing grade of dysplasia), but also in stromal plasma cells. Exogenous MIF inhibited apoptosis and promoted anchorage-independent growth of VACO-235 cells (maximal at 100 ng/mL). Homozygous deletion of Mif was associated with a reduction in the number and size of ApcMin/+ mouse adenomas (P = .025 for the difference in large [>7-mm] tumors) and decreased angiogenesis (43% decrease in mean tumor microvessel density), but there was no alteration in epithelial cell apoptosis or proliferation. CONCLUSIONS: MIF expression is increased in sporadic human colorectal adenomas, and exogenous MIF drives tumorigenic behavior of epithelial cells in vitro. Mif also promotes intestinal tumorigenesis (predominantly via angiogenesis) in the ApcMin/+ mouse. Therefore, MIF is a potential colorectal cancer chemoprevention target.  相似文献   
60.
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