细胞外热休克蛋白70及其生物学功能

热休克蛋白(HSP)一直被描述为一种细胞内蛋白质在胞内发挥一系列生物学作用,参与细胞内蛋白质的折叠、装配、降解和修复过程。近年来,有研究发现HSP70能被主动释放到胞外,成为细胞外HSP70(extracellular HSP70,eHSP70),但关于其功能尚不清楚。循环HSP70水平与多种疾病进程密切相关。有研究发现暴露于物理和心理刺激源作用下,HSP70可能通过脂筏或Exosome介导的分泌途径释放到细胞外,作为一种生物活性因子影响多种疾病的进程。     

猪苓多糖联合卡介苗诱导的细胞外热休克蛋白对巨噬细胞功能的影响

目的 研究猪苓多糖联合卡介苗刺激T24膀胱癌细胞株后,细胞外HSP的表达及其对J774A.1巨噬细胞TLR2、TLR4,胞内钙离子(Ca2+)、一氧化氮(NO)和活性氧(ROS)表达的影响,探讨膀胱内灌注卡介苗治疗浅表性膀胱癌的免疫启动和免疫调节机制.方法 用ELISA的方法检测猪苓多糖和卡介苗联合刺激T24膀胱癌细胞后胞外HSP90、HSP70、HSP60、HSP27的表达,胞外HSP作用于J774A.1巨噬细胞后,用流式细胞术检测J774A.1巨噬细胞表面TLR4和TLR2的表达,应用激光共聚焦扫描技术,检测J774A.1细胞内Ca2+、NO和ROS的动态变化.结果 猪苓多糖和卡介苗联合作用组胞外HSP的表达明显高于猪苓多糖和BCG单独使用组(P＜0.05),48h时胞外HSP的表达至峰值,且胞外HSP70呈优势表达;胞外HSP可上调J774A.1巨噬细胞TLR4的表达(P＜0.05),对J774A.1细胞内Ca2+、NO和ROS有明显的调节作用(P＜0.05).结论卡介苗体外直接刺激人T24膀胱癌细胞后,可表达细胞外HSP90、HSP70、HSP60、HSP27,猪苓多糖和卡介苗联合使用可增加其表达.细胞外HSP对J774巨噬细胞有一定的免疫调节作用.     

GRP94的功能及其与肿瘤的相关性

葡萄糖调节蛋白94(gloucose requlated protein 94,GRP94)是HSP90家族的成员,主要定位于内质网中.GRP94作为分子伴侣参与蛋白质的折叠、转运和分泌外,还参与了细胞凋亡以及抗原的提呈.GRP94与肿瘤的发生以及进展密切相关,肿瘤的分化程度越低,GRP94的表达也越高.GRP94又可将肿瘤特异性抗原提呈给专业提呈细胞启动特异性的免疫反应.GRP94在肿瘤的发生及转归中发挥了重要的作用.     

热休克蛋白在肿瘤免疫方面的研究进展

热休克蛋白(HSP)是细胞在应激条件下产生的一类高度保守的蛋白质,已被证实是一个强有力的免疫佐剂,在肿瘤免疫中充当了多重角色,对研制临床上有实用价值的肿瘤疫苗有重要的意义.此文综述了热休克蛋白及其在肿瘤免疫中的作用机制和在临床肿瘤疫苗研发中的应用前景.     

热休克蛋白90与戊型肝炎病毒重组衣壳蛋白P239相互作用的初步研究

目的 对前期研究中所筛选出的能够与戊型肝炎病毒(hepatitis E virus,HEV)重组衣壳蛋白颗粒P239存在特异性的相互作用的蛋白进行分析验证.方法 使用pull-down、MALDI-TOF-MS、免疫共沉淀技术及免疫荧光技术对与P239有潜在相互作用的蛋白进行鉴定和进一步分析.结果 MALDI-TOF-MS及免疫共沉淀技术,均表明该蛋白为热休克蛋白90(HSP90)并与P239相互作用.随后,对P239进入细胞的过程中胞内HSP90蛋白量及其分布的变化做了初步研究.发现虽然HSP90在蛋白总量上并没有发生明显的变化,但其定位却伴随着P239在胞内的迁移发生了由细胞膜向细胞核核周的转移.结论 HSP90可能参与了P239入胞后的转运并介导了HEV入胞后向效应细胞器的转运,为研究HEV的感染机制及对HEV的预防和控制提供了有益的线索.     

热休克蛋白70与肠道病毒感染

热休克蛋白70 (HSP70)是HSP70家族中的重要成员.HSP70的主要功能是作为分子伴侣参与蛋白质的折叠与修饰.在病毒感染时,HSP70参与机体的抗感染免疫,从而保护细胞.因而研究HSP70与肠道病毒的相互作用具有意义.     

结核菌感染中热休克蛋白对巨噬细胞的影响

热休克蛋白(heat shock protein,HSP)是生物界普遍存在的一种高度保守的蛋白质,对维持细胞生存和内环境的稳定起重要作用。在结核菌感染过程中机体或病原体的HSP被激活,影响巨噬细胞的自噬、凋亡和极化等作用。本文综述了结核菌感染中,能影响巨噬细胞功能的主要HSP的相关研究进展。     

热休克蛋白22研究进展

A newly identified 22 kD protein, which is named as heat shock protein22 (HSP22), is a member of sHSP (small heat shock protein) subfamily. It contains the α-crystallin domain in its C-terminal half, a hallmark of the subfamily of sHSP. HSP22 has Ser-Thr protein kinase activity and chaperone-like activity. HSP22 is expressed in multiple tissues, specially in skeletal muscle, placenta and heart. Previous studies showed that HSP22 involved in growth and transformation of cells, apoptosis of tumor, hypertrophy and apoptosis of myocardial cells.     

热休克蛋白70与肝癌

热休克蛋白70(HSP70)广泛存在于细胞中,在应激刺激后过表达,可以参与蛋白质的合成及受损蛋白的修复。HSP70在肝癌治疗中的作用日益受到重视:利用其特异性和免疫原性,靶向治疗肝癌。并且可以利用其"分子伴侣"的特点,作为肝癌疫苗,诱发机体抗肝癌的免疫反应。HSP70在肝癌治疗中已初显成效,但也存在很多问题,需要更加深入的研究。总之,HSP70在肝癌治疗中有很大的应用前景。     

HSP72过度表达对脂多糖刺激的巨噬细胞中NF-κB活性的影响

目的研究过度表达的热休克蛋白72(heat shock protein,HSP72)对脂多糖(lipopolysaccha-ride,LPS)刺激的巨噬细胞中NF-κB活性的影响.方法构建pCD-hsp72重组质粒,转染小鼠巨噬细胞RAW264.7,G418筛选稳定转染hsp72基因的细胞,Western印迹检测转染细胞HSP72的表达水平及LPS刺激后RAW264.7细胞内HSP72的表达水平、LPS刺激后转染细胞中IκBα的含量和胞核中NF-κB的含量的变化.结果构建pCD-hsp72重组质粒并转入巨噬细胞,获得稳定转染hsp72基因的细胞株,LPS刺激细胞内HSP72表达增加;HSP72可通过减少LPS刺激的巨噬细胞中IκBα的降解而抑制NF-κB活性.结论HSP72能抑制LPS激活的巨噬细胞中NF-κB的活化.     

Modulatory role of calreticulin as chaperokine for dendritic cell-based immunotherapy

Heat shock proteins (HSPs) play a regulatory role for maturation of antigen-presenting cells (APCs) such as dendritic cells (DCs) and macrophages. Whereas HSP70 has been shown to enhance the maturation of human DCs via a nuclear factor kappa-B (NF-κB)-dependent pathway, the regulatory role of calreticulin (CRT), which is a HSP with similar functions to HSP70, is not well studied. To investigate the role of CRT as adjuvant in cell activation and co-stimulatory responses we determined the effects of CRT on human APC maturation in comparison to that of HSP70. To facilitate eukaryotic endotoxin-free CRT protein expression, three different methods were compared. We demonstrate that CRT induces the maturation of human DCs and increases the production of proinflammatory cytokines via the NF-κB pathway. CRT-mediated maturation was qualitatively similar to that induced by HSP70. Interestingly, priming of monocytes with HSPs showed an even more prominent effect on maturation than exposure of immature DCs to these compounds. A higher expression of CD86, CD83 and CCR7 on mature DCs were found in response to CRT. Our data provide novel insights into the role of extracellular HSPs as chaperokines in the processes of APC generation and may thus be useful to improve adoptive immunotherapy.     

Message in a bottle: role of the 70-kDa heat shock protein family in anti-tumor immunity

Extracellular heat shock protein 70 (HSP70) is a potent agent for tumor immunotherapy, which can break tolerance to tumor-associated antigens and cause specific tumor cell killing by cytotoxic CD8+ T cells. The pro-immune effects of extracellular HSP70 are, to some extent, extensions of its molecular properties as an intracellular stress protein. The HSP70 are characterized by massive inducibility after stress, preventing cell death by inhibiting aggregation of cell proteins and directly antagonizing multiple cell death pathways. HSP70 family members possess a domain in the C terminus that chaperones unfolded proteins and peptides, and a N-terminal ATPase domain that controls the opening and closing of the peptide binding domain. These properties not only enable intracellular HSP70 to inhibit tumor apoptosis, but also promote formation of stable complexes with cytoplasmic tumor antigens that can then escape intact from dying cells to interact with antigen-processing cells (APC) and stimulate anti-tumor immunity. HSP70 may be released from tumors undergoing therapy at high local extracellular concentrations, and send a danger signal to the host leading to APC activation. Extracellular HSP70 bind to high-affinity receptors on APC, leading to activation of maturation and re-presentation of the peptide antigen cargo of HSP70 by the APC. The ability of HSP70-peptide complexes (HSP70-PC) to break tolerance and cause tumor regression employs these dual properties as signaling ligand and antigen transporter. HSP70-PC thus coordinately activate innate immune responses and deliver antigens for re-presentation by MHC class I and II molecules on the APC cell surface, leading to specific anti-tumor immunity.     

Heat shock proteins in human endometrium throughout the menstrual cycle

Human endometrium is a steroid-sensitive tissue and there isevidence that supports the viewpoint that heat shock proteins(HSP) are implicated in the regulation of steroid function.Therefore, in this study we examined the expression of variousmembers of the heat shock family of proteins in the steroid-responsivehuman endometrium. Western blot analysis revealed that the expressionof HSP90 showed minimal changes throughout the menstrual cycle.When normalized to the amount of HSP90, the expression of HSP27,HSP60 and the constitutive form of heat shock protein 70 (HSC70)increased progressively during the late proliferative and earlysecretory phases, and diminished in the mid- to late secretoryand menstrual phases. In contrast, the inducible form of heatshock protein 70 (HSP70) did not undergo these changes. Thecellular and subcellular localizations of these proteins wereexamined in human endometria by immunohistochemical staining.With the exception of HSP70, which was found primarily in theepithelial cells, the immunoreactivity for other heat shockproteins was found in both the stroraa and the epithelium. Immunoreactivityfor HSP27 was found in the lymphoid aggregates within endometrialstroma, and both HSP27 and HSP90 were found in endothelial cells.The immunoreactive heat shock proteins were found in the nucleiand/or cytoplasm of cells. However, no consistent nuclear versuscytoplasmic staining emerged, and such localization was irrespectiveof the site, the cell type or the phase of the menstrual cycle.Our findings show that endometrium has a full complement ofheat shock proteins. The menstrual cycle-dependent changes inthe amounts of heat shock protein suggest regulation by steroidhormones.     

细胞外热休克蛋白70的释放机制及免疫功能

热休克蛋白（heat shock protein，HSP）是机体细胞在受到热应激或其他应激状态下合成增多的一类蛋白质，在细胞的多种功能中起十分重要的作用。最近研究发现，正常人和多种疾病的循环血液和体液中存在热休克蛋白70。而且还发现这种存在于细胞外的热休克蛋白70（extracellular heat shock protein 70，eHSP70）可能作为免疫系统的“危险信号”（danger signal），调节免疫细胞的功能。     

空肠弯曲菌HSP43诱导自身免疫机理──分子模拟和抗原优势

我们曾发现空肠弯曲菌４３ｋＤ热休克蛋白（ＨＳＰ４３）能诱导小鼠产生自身免疫应答，本文则进一步分析了这种诱导作用的机理。二株针对ＨＳＰ６０保守区序列的单克隆抗体ＩＩＨ９和ＭＬ－３０不但能结合人及小鼠细胞中ＨＳＰ６０家族成员，而且也能结合ＨＳＰ４３，表明ＨＳＰ４３、人及小鼠ＨＳＰ６０三者均属同一家族成员，具有序列上的高度同源性。小鼠用空肠弯曲菌免疫后出现了针对１０种菌体蛋白的抗体，其中最早被诱导的抗体是针对ＨＳＰ４３的，并且该种抗体在随后８０ｄ观察期间内保持了较高活性，表明ＨＳＰ４３是优势抗原。本文结果提示，ＨＳＰ４３较易被免疫系统识别而产生应答，通过和宿主ＨＳＰ６０高度序列同源性而可能呈现分子模拟，从而诱导自身免疫损伤。     

Heat shock protein 60 (HSP60) immunoreactivity in gastric epithelium associated with Helicobacter pylori infection: a pitfall in immunohistochemically interpreting HSP60-mediated autoimmune responses

Previous studies have suggested that heat shock proteins (HSP) of Helicobacter pylori (H. pylori) are involved in the induction of autoimmunity mediated gastritis. In the present report, the cross-reactivity between H. pylori-related HSP60 and gastric epithelial cells was investigated by the indirect immunoperoxidase method using two monoclonal antibodies (mAb) against H. pylori-derived HSP60, H9 and H20. H9 is reactive with an epitope common to bacterial HSP60, while H20 is specific to H. pylori HSP60. A total of 70 paraffin-embedded gastric biopsy specimens were analyzed after heat-induced epitope retrieval. Both mAb were cross-reactive with the gastric epithelial cells, with a higher frequency seen for the H9-reactive epitope. The frequency of positive epithelial decoration was not significantly different between H. pylori-positive and H. pylori-negative gastric mucosae. A variety of epithelial and non-epithelial cells were immunostained with mAb H9, while mAb H20 was cross-reactive only with small intestinal epithelia. Reactivity was mainly located in the Golgi area and rarely in the cytoplasm. These results suggest a noteworthy pitfall in immunohistochemical interpretations of HSP60-associated autoimmune reactions in the gastric mucosa.     

The immune responses to human and microbial heat shock proteins in periodontal disease with and without coronary heart disease

The human 60 kDa and microbial 65 kDa heat shock proteins (HSP) have been implicated in the pathogenesis of chronic periodontitis (P) and coronary heart disease (CHD). We have studied four male non-smoking cohorts of 81 subjects, matched for age. Group (a) consisted of a healthy group with minimal gingivitis (n = 18), group (b) were patients with P (n = 23), group (c) patients with CHD and minimal gingivitis (n = 20) and group (d) patients with CHD and P (n = 20). T cells separated from peripheral blood were found to be primed to both microbial HSP65 and human HSP60 but significant CD4, human leucocyte antigen (HLA) class II-restricted proliferative responses were found only with the human HSP60 in patients with P (P < 0.001) and CHD without (P < 0.001) or with (P < 0.00001) periodontitis. Dose-dependent inhibition of T cell proliferative responses was carried out to determine the receptors involved in recognition of HSP60 and HSP65. Monoclonal antibodies to CD14 showed inhibition of T cell proliferation stimulated by both HSP60 and HSP65, consistent with the role of CD14 as a receptor for these HSPs in P and CHD. The toll-like receptor 2 (TLR-) and TLR-4 were then studied and these showed that TLR-4 was recognized by microbial HSP65, whereas TLR-2 was recognised by human HSP60 in both P and CHD. However, a dissociation was found in the HSP60 and TLR4 interaction, as TLR4 appeared to have been recognized by HSP60 in P but not in CHD. The results suggest an autoimmune or cross-reactive CD4(+) class II-restricted T cell response to the human HSP60 in P and CHD. Further studies are required to determine if there is a common epitope within HSP60 that stimulates T cell proliferation in P and CHD.     

Resolution-associated molecular patterns (RAMP): RAMParts defending immunological homeostasis?

The resolution of inflammation is central to the maintenance of good health and immune homeostasis. Recently, several intracellular stress proteins have been described as having extracellular properties that are anti-inflammatory or favour the resolution of inflammation. We propose that these molecules should be defined as resolution-associated molecular patterns (RAMPs). RAMPs are released at times of cellular stress and help to counterbalance the inflammatory effects of pathogen-associated (PAMPs) and damage-associated (DAMPs) molecular patterns. We propose that heat shock protein 10 (HSP10), αB-crystallin (αBC), HSP27 and binding immunoglobulin protein (BiP) should be considered founding members of the RAMP family. A greater understanding of RAMP biology may herald the development of novel immunotherapies.