caveolin-1 siRNA对成釉细胞中CD147糖基化及MMP-2表达的影响

目的:研究caveolin-1的表达对小鼠成釉细胞CD147糖基化及MMP-2表达的影响.方法:首先利用细胞免疫荧光技术检测体外培养的小鼠成釉细胞中caveolin-1、CD147和MMP-2蛋白的表达;然后利用siRNA技术封闭小鼠成釉细胞中caveolin-1的表达,实时定量荧光PCR和免疫印迹试验分别检测caveolin-1、CD147和MMP-2在转录水平和蛋白水平的表达情况,并统计学分析.结果:caveolin-1、CD147和MMP-2蛋白表达于体外培养的小鼠成釉细胞中;caveolin-1siRNA转染成釉细胞后caveolin-1mRNA和MMP-2mRNA的表达量明显降低,但CD147mRNA的表达量没有明显变化;caveolin-1、高糖型CD147和MMP-2的蛋白表达量均降低.结论:caveolin-1、CD147和MMP-2表达于小鼠成釉细胞中,提示3者参与成釉细胞生物学过程;在体外培养的成釉细胞中,封闭caveolin-1基因的表达可降低HG-CD147和MMP-2的表达.     

肿瘤转移相关基因CD44v6与p53在胃癌组织中的表达和预后

目的探讨肿瘤转移促进基因CD44v6和肿瘤转移抑制基因p53在胃癌组织中的表达与预后.方法45例浸润性胃癌组织来自哈尔滨医科大学附属第二医院病理科.采用sABC方法进行CD44v6和p53免疫组织化学检测.结果CD44v6在胃癌组织中表达率为53.3%(24/45).其中低分化腺癌伴印戒细胞癌的表达率高(16/24,66 7%).p53在胃癌组织中的表达率为75.6%(34/45),而在组织学的分型方面无明显差别.结论p53是最先参与肿癌侵袭和转移的抑癌基因.CD44v6具有在不同组织学类型的胃癌中表达率不同的特点,结果表示CD4v6的表达率可判断不同组织学类型胃癌的预后.     

SPATA12基因在多种肿瘤中的组织芯片表达谱分析

为了检测生精相关基因SPATA12在多种肿瘤组织中的表达及其与临床病理特征的关系,采用数字虚拟Northern方法分析SPATA12在41种正常组织及其相应肿瘤组织中的表达丰度;利用组织芯片技术结合原位杂交的方法,对96例多器官肿瘤组织芯片和208例肺肿瘤组织芯片样本中SPATA12基因的表达情况进行检测.虚拟Northern结果显示,SPATA12主要表达于正常睾丸组织以及少部分肺癌组织中.组织芯片原位杂交结果显示,SPATA12在多种肿瘤组织中表达频率不一,主要在皮肤恶性黑色素瘤、前列腺癌及前列腺慢性炎症组织、胃癌、结肠癌、甲状腺乳头状癌等肿瘤组织中高表达;在肺肿瘤组织中,SPATA12主要表达于非小细胞肺癌,其中在腺癌、鳞癌、类癌和大细胞癌组织的阳性表达率分别为16.13%,29.17%,30%和100%.SPATA12的阳性表达率与肺癌不同病理类型相关(P<0.01),而与年龄、性别以及临床分级无关(P>0.05).SPATA12基因具有肿瘤-睾丸抗原的组织表达谱特点,其阳性表达与肺肿瘤组织的不同病理类型存在明显的相关性,对肺肿瘤的分子分型有一定的参考价值.     

环亲和素A的重组表达及其促进肝癌细胞侵袭转移的体外研究

为研究环亲和素A（CyclophilinA,CyPA）与肝癌转移的关系,用原核重组表达并纯化了CyPA。在不同浓度的CyPA刺激下,利用凝胶酶谱检测人肝癌细胞FHCC-98分泌基质金属蛋白酶（matrix metalloproteinases,MMPs）的能力。选择合适的刺激浓度,用BordenChamber检测肝癌细胞的侵袭能力。同时用抗CD147的抗体阻断CypA与其受体CD147的结合,检测阻断后FHCC-98在CyPA刺激下分泌MMPs及转移的能力。结果表明重组表达的CyPA能促进FHCC-98分泌激活或非激活形式的MMP-2并能促进FHCC-98的转移,而抗CD147的抗体能阻断其作用。实验结果表明：环亲和素A能与肝癌细胞表面的受体分子CD147结合,促进肝癌细胞的转移,提示其在“炎-癌”链中起到一定的作用。     

CD138蛋白在软组织肉瘤中的表达

目的 CD138(SDC1/Syndecan-1)蛋白在多种肿瘤中表达并发挥着重要作用,但在软组织肉瘤中很少报道,本研究旨在探讨CD138蛋白在软组织肉瘤中的表达情况。方法收集石河子大学医学院第一附属医院病理科213例软组织肿瘤(包括脂肪肉瘤、横纹肌肉瘤、平滑肌肉瘤、隆突性皮肤纤维肉瘤、未分化多形性肉瘤、纤维肉瘤、尤文肉瘤和上皮样肉瘤)和21例正常脂肪组织,采用组织芯片技术,运用免疫组织化学检测这8种软组织肉瘤组织中CD138蛋白的表达情况;运用癌症基因组图谱数据库(The Cancer Genome Atlas,TCGA)分析肉瘤患者无病生存率和总体生存率状况与CD138基因表达高低之间的关系。结果 CD138蛋白在软组织肉瘤中着色定位于细胞膜和细胞质,其中18.8%呈现1+弱阳性,12.2%呈现2+强阳性;而强阳性染色(2+)率分别为:脂肪肉瘤38.7%(12/31),上皮样肉瘤12.5%(1/8),未分化多形性肉瘤5.9%(2/34),尤文肉瘤11.1%(2/18),隆突性皮肤纤维肉瘤5.3%(2/38),纤维肉瘤11.1%(2/18),平滑肌肉瘤9.5%(4/42)和横纹肌肉瘤4.2%(1/24)。与其他七种软组织肉瘤染色相比,CD138蛋白在脂肪肉瘤中显著高表达,且差异具有统计学意义(χ~2=30.01,P0.001)。与正常脂肪组织相比,CD138蛋白在脂肪肉瘤中差异性高表达(χ~2=12.668,P=0.002)。进一步对脂肪肉瘤亚型染色数据分析发现,CD138蛋白主要在去分化脂肪肉瘤细胞质中着色;与分化良好的脂肪肉瘤相比,CD138蛋白在去分化脂肪肉瘤中显著性高表达(χ~2=18.393,P0.001)。CD138基因表达高低与肉瘤患者的存活状况无明显相关性(P0.05)。结论 CD138蛋白在软组织肉瘤中均存在一定程度表达,在脂肪肉瘤组织中高表达并与其组织学亚型相关。     

As2O3对消化道肿瘤的粘附分子E-CD、CD44表达的影响

[目的]通过观察消化道肿瘤术前短时间,小剂量As2O3应用,探讨As2O3对消化道肿瘤的E-CD、CD44表达变化的影响.[方法]分别在手术前给与8例确诊为消化道肿瘤的患者As2O3,治疗3d.在用药前和术中提取患者的病理组织.利用免疫组织化学法检测8例消化道肿瘤组织中的E-CD、CD44表达情况.[结果]应用As2O3注射液化疗后与用药前比较,肿瘤组织中E-CD、CD44表达下调.[结论]体内实验证实,As2O3的抗肿瘤作用与下调CD44、E-CD有关,抑制肿瘤的浸润与转移而起到抑制肿瘤的作用.     

乳腺癌中肿瘤相关巨噬细胞的浸润与eIF4E表达的关系

目的:探讨乳腺癌组织中CD163~+肿瘤相关巨噬细胞的浸润情况与eIF4E表达及其与临床病理特征的关系,并分析两者的相关性.方法:收集乳腺癌组织92例及癌旁正常乳腺组织74例,应用Maxvision法进行免疫组化染色检测eIF4E及CD163表达,并分析其与乳腺癌临床病理特征的关系.结果:乳腺癌组织中的CD163表达量高于癌旁正常组织(P0.001),乳腺癌组织中的eIF4E表达量高于癌旁正常乳腺组织(P0.001),CD163的表达与ki67表达相关(P0.05),CD163与eIF4E的表达呈正相关(r=0.273,P0.05).结论:乳腺癌中CD163和eIF4E的表达明显高于癌旁组织,CD163的过表达与ki67的表达相关,同时与eIF4E呈正相关,提示CD163与eIF4E的共同作用可能参与了乳腺癌的发生与发展.     

前列腺癌中miRNAs的表达及其临床意义

MicroRNAs属于内源性小分子非编码RNAs,它在多种肿瘤病理学过程中起着关键的调控作用。不同类型肿瘤中的microRNA的表达谱可用于疾病的诊断及预后的判断,且癌症组织中miRNAs的异常表达与临床病理学指标有关。外周血与组织中的miRNAs均有可能作为生物学标记物用于预测疾病的复发及患者生存期。此外,许多miRNAs还具有一定的治疗价值。本文旨在探讨组织来源与循环血液中miRNAs的诊断及预后在前列腺癌中的临床意义。     

CD44基因调节炎症的研究进展

CD44是一种Ⅰ型跨膜糖蛋白,广泛表达于内皮细胞、间充质细胞及中胚层来源的细胞和组织。由于CD44在机体内的广泛表达以及多种可变剪切体的存在,使得研究所涉及的炎症模型不同,CD44在炎症过程中所起的作用也不一样。明确CD44在炎症过程的作用,不仅有助于进一步认识炎症的作用机制,还可为研发治疗炎症的新型生物阻断制剂提供思路。     

趋化因子 CXCL16及其受体 CXCR6在恶性肿瘤中的表达与作用

趋化因子在恶性肿瘤的发生、发展、肿瘤微环境形成及抗肿瘤免疫中发挥了重要作用。新的趋化因子CXCL16及其受体 CXCR6正日益受到关注。研究发现 CXCL16/CXCR6在多种人类恶性肿瘤中高表达,在多数肿瘤中可促进肿瘤的生长、转移和复发,但在有些肿瘤中却作用相反。此外,CXCL16/CXCR6还可通过诱导CD4+/CD8+T 细胞、自然杀伤细胞等免疫细胞参与抗肿瘤免疫以及肿瘤微环境的形成。明确 CXCL16/CXCR6在肿瘤中的作用及其分子机制将有助于抗肿瘤研究的深入。     

Prevention of HIV-1 glycoprotein transport by soluble CD4 retained in the endoplasmic reticulum

The envelope glycoprotein (gp120/41) of the human immunodeficiency virus (HIV-1) attaches the virus to the cellular CD4 receptor and mediates virus entry into the cytoplasm. In addition to being required for formation of infectious HIV, expression of gp120/41 at the plasma membrane causes the cytopathic fusion of cells carrying the CD4 antigen. The expression of gp120/41 is therefore an ideal target for therapeutic strategies designed to combat AIDS. Here we show that expression of a soluble CD4 molecule, mutated to contain a specific retention signal for the endoplasmic reticulum, blocks secretion of gp120 and surface expression of gp120/41, but does not interfere with transport of wild-type CD4. By blocking transport of the HIV glycoprotein, this retained CD4 molecule prevents the fusion of CD4 cells that is normally caused by the HIV glycoprotein. Expression of the retained CD4 molecule in human T cells might therefore be useful in the intracellular immunization procedure suggested by Baltimore.     

HAb18G/CD147真核荧光蛋白的表达及鉴定

构建肝癌相关抗原HAb18G／CD147全长及缺失片段E51（第22—50位氨基酸缺失）的真核荧光蛋白表达载体,进一步研究该基因在肝细胞肝癌发生中的作用。通过PCR及Overlapping PCR的方法获得目的基因．与荧光载体pEGFP—N1双酶切、连接、转化E．coli JM109．构建含有肝癌相关抗原HAb18G／CD147全长及E51的真核荧光蛋白表达载体．并经限制性酶切及序列分析证明插入是否正确。用阳离子脂质体介导转染COS-7细胞,进行瞬时表达;荧光显微镜观察EGFP表达,通过流式细胞术检测蛋白的表达情况,明胶酶谱法鉴定其功能。成功地构建了真核荧光蛋白表达载体pEGFP—N1／HAb18G、pEGFP—N1/E51,并经限制性酶切及序列分析证明外源基因插入正确;流式细胞术鉴定该蛋白表达正确;功能实验证实缺失片段E51不具有诱导成纤维细胞分泌MMPs的功能．结果显示HAb18G／CD147基因第22—50位氨基酸与其刺激成纤细胞分泌MMP和功能有密切关系。实验结果为HAb18G蛋白分子的生物学功能研究奠定了基础。     

A soluble form of CD4 (T4) protein inhibits AIDS virus infection

CD4 (T4) is a glycoprotein of relative molecular mass 55,000 (Mr 55K) on the surface of T lymphocytes which is thought to interact with class II MHC (major histocompatibility complex) molecules, mediating efficient association of helper T cells with antigen-bearing targets. The CD4 protein is also the receptor for HIV, a T-lymphotropic RNA virus responsible for the human acquired immune deficiency syndrome (AIDS) (refs 4-7). To define the mechanisms of interaction of CD4 with the surface of antigen-presenting cells and with HIV, we have isolated the CD4 gene and expressed this gene in several different cellular environments. Here we describe an efficient expression system in which a recombinant, soluble form of CD4 (sCD4) is secreted into tissue culture supernatants. This sCD4 retains the structural and biological properties of CD4 on the cell surface, binds to the envelope glycoprotein (gp110) of HIV and inhibits the binding of virus to CD4+ lymphocytes, resulting in a striking inhibition of virus infectivity.     

Enhancement of T-cell activation by the CD43 molecule whose expression is defective in Wiskott-Aldrich syndrome

CD43 (sialophorin, leukosialin, leukocyte large sialoglycoprotein), a heavily sialylated molecule found on most leukocytes and platelets, was initially identified as a major glycoprotein of mouse, rat and human T cells. CD43 expression is defective on the T cells of males with the Wiskott-Aldrich syndrome, an X chromosome-linked recessive immunodeficiency disorder. Affected males are susceptible to opportunistic infections and do not respond to polysaccharide antigens, reflecting defects in cytotoxic and helper T-cell functions. Anti-CD43 monoclonal antibodies have a modest costimulatory effect on T cells, natural killer cells, B cells and monocytes, and one such antibody has been shown to activate T cells directly. To investigate a possible physiological role for CD43, a complementary DNA encoding the human protein was introduced into an antigen-responsive murine T-cell hybridoma. We observed that CD43 enhances the antigen-specific activation of T cells and that the intracellular domain of CD43, which is hyperphosphorylated during T-cell activation, is required for this function. We also found that antigen-presenting cells can bind specifically to immobilized purified CD43 and that the binding can be inhibited by liposomes containing CD43 as well as by anti-CD43 monoclonal antibodies.     

The B-cell surface protein CD72/Lyb-2 is the ligand for CD5.

The glycoprotein CD5 is expressed on the surface membrane of all mature T cells and a small proportion of B lymphocytes. Its exact role in immune interactions is still unknown. Studies indicate that CD5 functions both in mice and humans as a receptor, delivering co-stimulatory signals to T cells in a manner similar to CD2 (ref. 11) and CD28 (ref. 12). Anti-CD5 antibodies stimulate both T-cell proliferation mediated by CD3 in association with the T-cell receptor and secretion of interleukin-2 and expression of its receptor, as well as inducing an increase in intracellular Ca2+ concentration (refs 5-10). To identify the ligand for CD5 we purified the human CD5 protein, labelled it with biotin and used it as a probe. Here we report that CD5 specifically interacts with the cell-surface protein CD72 exclusive to B cells. This interaction is blocked by anti-CD72 antibodies, but not by any other anti-B-cell antibodies. Moreover, non-B cells (mouse L-cell fibroblasts and human Jurkat T cells) expressing a transfected human CD72 complementary DNA could bind to the CD5-biotin conjugate. The results demonstrate that the B-cell surface protein CD72 (Lyb-2 in mice) is the ligand for CD5.     

Lymphocyte activation by HIV-1 envelope glycoprotein

Cell activation by phytohaemagglutinin, phorbol ester and by the supernatant of phytohaemagglutinin-stimulated peripheral blood mononuclear cells induces the expression and cytopathic effects of latent human immunodeficiency virus type-1 (HIV-1) in vitro. The lymphocyte surface protein CD4 has been identified as a receptor for HIV-1 and binds the viral envelope glycoprotein (gp120). In the light of evidence indicating that one natural function of CD4 is as a growth factor receptor, we examined the ability of native gp120 to activate resting CD4-bearing lymphocytes. Our results indicate that gp120 has innate biological activity as a result of a specific interaction with CD4, inducing increases in intracellular levels of inositol trisphosphate and of calcium, and in interleukin-2 receptor expression and cell motility.     

Intercellular adhesion molecule-1 is an endothelial cell adhesion receptor for Plasmodium falciparum

The primary event in the pathogenesis of severe malaria in Plasmodium falciparum infection is thought to be adherence of trophozoite- and schizont-infected erythrocytes to capillary endothelium, a process called sequestration. Identifying the endothelial molecules used as receptors is an essential step in understanding this disease process. Recent work implicates the membrane glycoprotein CD36 (platelet glycoprotein IV; refs 2-5) and the multi-functional glycoprotein thrombospondin as receptors. Although CD36 has a widespread distribution on microvascular endothelium, it may not be expressed on all capillary beds where sequestration occurs, especially in the brain. The role of thrombospondin in cell adhesion, in vitro or in vivo, is less certain. We have noticed that some parasites bind to human umbilical-vein endothelial cells independently of CD36 or thrombospondin. To screen for alternative receptors, we have developed a novel cell-adhesion assay using transfected COS cells, which confirms that CD36 is a cell-adhesion receptor. In addition, we find that an endothelial-binding line of P. falciparum binds to COS cells transfected with a complementary DNA encoding intercellular adhesion molecule-1. As this molecule is widely distributed on capillaries and is inducible, this finding may be relevant to the pathogenesis of severe malaria.     

Interaction between CD4 and class II MHC molecules mediates cell adhesion

The CD4 glycoprotein is expressed on T-helper and cytotoxic lymphocytes which are restricted to class II major histocompatibility complex (MHC) antigens on target cells. Antibody inhibition studies imply that CD4 acts to increase the avidity of effector-target cell interactions. These observations have led to the speculation that CD4 binds to a monomorphic class II antigen determinant, thereby augmenting low affinity T-cell receptor-antigen interactions. However, no direct evidence has been presented indicating that CD4 and class II molecules interact. To address this issue, we have used a vector derived from simian virus 40 (SV40) to express a complementary DNA (cDNA) encoding the human CD4 glycoprotein. When CV1 cells expressing large amounts of the CD4 protein at the cell surface are incubated with human B cells bearing MHC-encoded class II molecules, they are bound tightly to the infected monolayer, whereas mutant B cells which lack class II molecules fail to bind. Furthermore, the binding reaction is specifically inhibited by anti-class II and anti-CD4 antibodies. Thus, the CD4 protein, even in the absence of T-cell receptor-antigen interactions, can interact directly with class II antigens to function as a cell surface adhesion molecule.     

The T lymphocyte glycoprotein CD2 binds the cell surface ligand LFA-3

CD2 (known also as T11 (ref. 1), LFA-2 (ref. 2) and the erythrocyte rosette receptor (ref. 3] is a functionally important T lymphocyte surface glycoprotein of relative molecular mass 50,000 to 58,000 (Mr 50-58 K) which appears early in thymocyte ontogeny and is present on all mature T cells. Monoclonal antibodies to CD2 inhibit cytotoxic T-lymphocyte (CTL)-mediated killing by binding to the T lymphocyte and blocking adhesion to the target cell. Such antibodies also inhibit T helper cell responses including antigen-stimulated proliferation, interleukin-2 (IL-2) secretion, and IL-2 receptor expression. Certain combinations of monoclonal antibodies to CD2 epitopes trigger proliferation of peripheral blood T lymphocytes, cytotoxic effector function and expression of IL-2 receptors by thymocytes, resulting in thymocyte proliferation in the presence of exogenous IL-2 (ref. 11). These findings suggest that CD2 can function in signalling as well as being an adhesion molecule. To understand the role of CD2 in T-cell adhesion and activation, it is essential to define its natural ligand. Our previous observation that purified CD2 inhibits rosetting of T lymphocytes with sheep erythrocytes and can be absorbed by sheep erythrocytes suggested it also might bind with detectable affinity to human cells. We now report that CD2 binds to a cell-surface antigen known as lymphocyte function-associated antigen-3 (LFA-3) with high affinity, and can mediate adhesion of lymphoid cells via interaction with LFA-3.