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Toll样或非Toll样配体佐剂研究进展 总被引：1，自引：0，他引：1
有效的疫苗含有可活化天然免疫系统的佐剂组分,从而激发抗原特异性的免疫应答.Toll样受体(toll-like receptors,TLR)是一种重要的天然识别受体,大多数疫苗佐剂都是TLR配体.少数佐剂通过其他的识别受体和信号通路,以TLR非依赖性的方式来活化天然免疫系统.非Toll样配体佐剂的作用靶点主要是近来发现的NOD样受体(Nod-like receptor,NLR)、RIG(retinoic-acid-inducible gene)样受体(RIG-like receptors,RLR)等胞内天然免疫受体.文章对Toll样或非Toll样配体作为疫苗佐剂的研究进行了综述. 相似文献
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在细菌和DNA病毒的基因组中广泛存在着以非甲基化的胞嘧啶—鸟嘌呤核苷酸为核心的CpG基序。作为一种病原相关的分子模式（pathogen-associated molecular pattern, PAMP）,含有CpG基序的寡聚脱氧核苷酸（CpG oligodeoxynucleotides,CpG ODN）能激活包括B淋巴细胞和类浆细胞在内的多种免疫细胞,并诱导产生以Th1型细胞免疫反应为主的免疫应答。CpG ODN在哺乳动物细胞中的受体是Toll样受体（Toll-like receptors, TLRs）家族中的Toll样受体 9（TLR9）。TLR9所介导的免疫激活作用在某些传染病的预防、新型疫苗佐剂的开发及过敏性疾病和癌症的治疗中有着巨大的应用前景。 相似文献
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Toll样受体(TLRs)是一组保守的蛋白质,除了在先天免疫和适应性免疫反应的启动和调控中发挥重要作用,还参与病原体识别。目前,已鉴定到若干个识别不同配体的鸡TLRs,在刺激鸡对病原体产生宿主反应中发挥重要作用。然而,通过哪个TLRs对鸡免疫系统进行调节尚未明了。本试验通过分别向试验鸡肌肉注射TLR4和TLR21相应的配体脂多糖(LPS)和CpG寡聚脱氧核苷酸(ODNs),对其刺激鸡免疫反应的动力学特性进行了研究。在注射TLR配体2、6、12和24h时,可在脾脏中检测到细胞因子的相应表达。结果表明,LPS能在试验早期强烈诱导免疫系统基因表达的上调,包括IFN-γ、IL-10和IL-1β。CpG ODNs能促进MHC-Ⅱ、IFN-γ和IL-10的上调。而对CpG ODNs的应答比对LPS的应答略迟。在对LPS的反应中,IFN-α基因的表达显著增加,而在对CpG ODNs的反应中无明显变化。进一步试验将对鸡TLR激活的分子机制或应用TLR激动剂作为疫苗佐剂进行研究。 相似文献
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Toll样受体是天然免疫中最早发现的模式识别受体,是生物界最古老的免疫系统组成部分之一,在识别病原和影响免疫应答方面具有非常关键的作用。Toll样受体8(TLR8)属于Toll样受体中的TLR7/8/9亚家族,通过识别配体激活信号级联反应,导致促炎细胞因子的产生,发挥抗病毒和抗细菌感染作用。论文就TLR8的结构与活化、配体识别、细胞分布、信号通路、细胞因子产生和疾病相关性等进行简要综述,可使人们更加全面地认识TLR8,对于动物免疫系统的研究以及动物疫病的防控具有一定的参考意义。 相似文献
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多糖可促进免疫调节,具有多靶点、多功能和多因子效应,因此可广泛用作兽用疫苗免疫佐剂。多糖作为疫苗佐剂可提高免疫动物脾脏、胸腺和法氏囊等免疫器官指数,增强巨噬细胞吞噬活性及抗原递呈能力,增强NK细胞杀伤能力,促进树突细胞的成熟和分化,增强机体对抗原的摄取能力,影响T细胞亚群的种类和数量,改变Th1、Th2型免疫应答反应的类型,促进B淋巴细胞增殖,刺激细胞因子及抗体的产生等。而多糖作为配体通过与Toll样受体(Toll-like receptor,TLR)、甘露糖受体(mannose receptor,MR)、C型凝集素受体(C-type lectins receptor,CLR)、清道夫受体(scavenger receptor,SR)等受体分子结合,激活下游信号通路,进而发挥上述免疫活性。文章主要从上述几方面对多糖作为兽用疫苗佐剂的作用机制进行阐述,以期为多糖的进一步开发和应用提供参考。 相似文献
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贾鹏鹏 《国外畜牧学(猪与禽)》2013,33(10):64-66
Toll样受体（Toll-like receptors,TLRs）是近年来发现的先天性免疫跨膜受体和信号转导受体,是病原模式识别（Pathogen-Associated Molecular Patterns,PAMP）受体之一.目前已经识别了10种鸡的Toll样受体（chicken Toll-Like Receptor,chTLRs）.TLRs分布于鸡的不同器官、组织和细胞;由于参与不同的免疫应答,不同的TLR在鸡体中的表达丰度也不相同.本实验,利用RT-PCR方法从三黄鸡外周血淋巴白细胞中扩增出鸡Toll样受体1、4、7基因（TLR1、4、7）.结果显示,扩增出的TLR1基因片段为737 bp,TLR4基因片段为1 246 bp,TLR7基因片段为533 bp,与GenBank中鸡TLR序列同源性达98％～99.8％. 相似文献
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Toll样受体(TLRs)是一类细胞外N-端具有富含亮氨酸重复(LRRs)结构域和细胞内C-端具有Toll/白介素(IL)-1受体(TIR)结构域的跨膜蛋白,是连接天然免疫和获得性免疫的桥梁。TLR9作为其中的一员,在病毒、细菌病原体免疫中发挥重要作用。本文从以下几个方面介绍了TLR9的研究进展来充分了解TLR9在免疫反应中的作用,以期为疫苗的开发和相关疾病的治疗提供新的角度。 相似文献
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Toll样受体(toll-like receptor,TLR)是存在于机体内的一类重要的模式识别受体,在机体天然免疫中起重要作用,可识别一种或多种特定的微生物病原体及其产物共有的高度保守的分子结构,即病原相关分子模式(pathogen associated molecular pattern,PAMP),启动针对入侵病原体的早期应答,诱发获得性免疫反应。对TLRs家族的研究有助于明确病原体被机体识别的本质,有助于阐明天然免疫及炎症反应机制,为免疫系统失调所致疾病的治疗提供新的思路,为新型疫苗(如DNA疫苗)和免疫调节剂的研发提供新的理论依据。 相似文献
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Bovine cytosol androgen receptor (ARC) concentrations were examined simultaneously in various regions of the uterus and in ovarian tissues of cows, and were related to cytosol estrogen (ERC) and progesterone receptor (PRC) concentrations and circulating steroid levels. ERC concentrations were 3-7-fold and PRC concentrations 13-29-fold those of ARC in bovine endometrial and myometrial tissues. When serum progesterone levels were low, both endometrial and myometrial ARC, endometrial ERC, and endometrial and myometrial PRC concentrations were higher (p < 0.05) than those observed during higher progesterone concentrations. Because serum 5 alpha-dihydrotestosterone (5 alpha-DHT) concentrations were higher during the luteal phase, it is possible that ARC was down-regulated by this natural ligand at this phase of the cycle. There were no differences between uterine horns in endometrial or myometrial ARC concentrations. Bovine cervical and ovarian stromal tissue also contained ARC, and the concentrations were about the same as in the endometrium and the myometrium. The relative binding affinities (RBAs) of some steroid hormones towards ARC in vitro were: the synthetic compound R1881 (146%), 5 alpha-dihydrotestosterone (100%), testosterone (75%) while estradiol-17 beta, progesterone and dexamethasone had lower RBAs (2, < 1, < 1% respectively). Cytosol androgen receptor concentrations correlated significantly with cytosol progesterone (PRC) and estrogen receptor (ERC) concentrations, both in the endometrium and myometrium. These data show that androgens, such as 5 alpha-DHT, may participate the endocrine regulation of bovine reproductive tissues. 相似文献
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给摘除卵巢绵羊埋植雌激素后，采取其子宫肉阜、肉阜间子宫内膜、肌层和其他器官组织样品用于催产素受体（ｒＯＴ）测定。３种子宫组织和输卵管含有ｒＯＴ；阴道、肌肉、小肠、肝组织中ｒＯＴ浓度不可测。子宫组织中ｒＯＴ仅具有单一类型的结合点，Ｋｄ值为１．３５ｎｍｏｌ／Ｌ，最大结合容量为３０２．８ｆｍｏｌ／ｍｇ蛋白。 相似文献
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病毒受体及其研究现状 总被引：3，自引：1，他引：2
受体在宿主细胞与病毒的相互作用中起着极其重要的作用。病毒受体的特性与病毒的宿主范围、组织嗜性有密切关系,是病毒致病性的主要因素之一。病毒受体的研究方法有经典的研究方法,也有现代分子生物学方法。在病毒受体的研究中,通常以分离纯化的细胞膜代替活体细胞来研究病毒受体。通过对病毒与细胞受体相互作用的深入研究,人们已经发现很多受体阻断剂例如植物凝集素和肝素等物质可以阻断病毒与受体的结合,从而为病毒病的防控提供繁殖一些有效的新方法。 相似文献
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Mari Spildrejorde Stephen J. Curtis Belinda L. Curtis Ronald Sluyter 《Veterinary immunology and immunopathology》2014,157(1-2):105-110
Binding of extracellular adenosine 5′-triphosphate (ATP) or lipopolysaccharide (LPS) to the damage-associated molecular pattern receptor P2X7 or the pathogen-associated molecular pattern receptor Toll-like receptor (TLR)4, respectively, can induce the release of the pleiotropic cytokine interleukin (IL)-1β in humans and mice. However, the release of IL-1β in dogs remains poorly defined. Using a canine IL-1β enzyme-linked immunosorbent assay, this study investigated whether ATP or LPS could induce IL-1β release in a canine blood-based assay. Short-term incubations (30 min) with ATP induced IL-1β release in LPS-primed canine blood, and this process could be near-completely impaired by the P2X7 antagonist, A438079. In contrast, ATP failed to induce IL-1β release from blood not primed with LPS. ATP-induced IL-1β release was observed with LPS-primed blood from eight different pedigrees or cross breeds. Long-term incubations (24 h) with LPS induced IL-1β release in canine blood in a concentration-dependent manner. This process was not altered by co-incubation with A438079. LPS-induced IL-1β release was observed with blood from 10 different pedigrees or cross breeds. These results demonstrate that both extracellular ATP and LPS can induce IL-1β release in dogs, and that ATP- but not LPS-induced IL-1β release in blood is dependent on P2X7 activation. These findings support the role of both P2X7 and TLR4 in IL-1β release in dogs. 相似文献
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Saba CF Rogers KS Newman SJ Mauldin GE Vail DM 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2007,21(5):1056-1059
BACKGROUND: Reports of mammary-gland tumors in male dogs are lacking. OBJECTIVE: To describe the clinical characteristics of mammary-gland tumors in male dogs. ANIMALS: Eight male dogs diagnosed with mammary-gland tumors. METHODS: Retrospective study. Medical databases from 3 institutions were searched. Medical records were abstracted, and owners and referring veterinarians contacted for follow-up information. Tissues were reviewed for histologic type, and immunohistochemical staining for estrogen and progesterone receptors (ER, PR) was performed. RESULTS: Eight dogs with histologically confirmed mammary-gland tumors were included in this retrospective study. Median age at diagnosis was 11.5 years. Four dogs were sexually intact; 4 were neutered. All were purebred. Mammary-gland tumors were incidental findings in 7 of 8 dogs. All dogs were treated with only surgical excision. All but 1 dog had benign epithelial tumors. The dog with the malignant tumor was the only dog to develop possible local recurrence but de novo tumor development cannot be excluded. No dog had evidence of metastatic disease at diagnosis. Based on institutional population data, it was determined that female dogs are 62 times more likely to develop mammary-gland tumors than male dogs (P < .001). Estrogen-receptor expression was strong in the majority of tumors; progesterone-receptor expression, although present in all tumors, was less intense. CONCLUSIONS/CLINICAL IMPORTANCE: This study suggests that mammary-gland tumors in male dogs are rare, usually benign, and surgery alone can provide long-term control in most dogs. 相似文献
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化学感受受体在昆虫的觅食、食物选择、交配和产卵等行为中发挥着重要作用。随着果蝇、按蚊、蜜蜂、赤拟谷盗和家蚕等昆虫基因组测序的完成。各物种中完整化学感受受体（包括嗅觉受体和味觉受体）得以鉴定,并从中鉴定出与气味识别、食物选择密切相关的受体基因,如果蝇的二氧化碳受体基因DmGr21a和DmGr63a,糖受体DmGr5a,以及冈比亚按蚊识别人类气味的AgOrl等。其中,昆虫的味觉受体功能与昆虫食物选择、大量取食直接相关。本文就目前昆虫基因组中味觉受体的鉴定、进化、表达和功能等方面的研究进展进行了综述。对味觉受体功能的研究,将有助于我们认识昆虫味觉编码的分子基础和神经调控网络,也是研究昆虫与植物相互关系的热点。 相似文献
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Takuya MURATA Kazumi NARITA Toru ICHIMARU 《The Journal of reproduction and development》2014,60(1):55-61
Estrogen action is mediated through several types of receptors (ERs), such as ERα, ERβ
and putative membrane ERs. Oxytocin receptor (OTR) and ER expression levels in the rat
uterus are regulated by estrogen; however, which types of ERs are involved has not been
elucidated. This study examined OTR, ERα and ERβ levels in ovariectomized rats treated
with 17β-estradiol (E2), an ERα agonist (PPT), an ERβ agonist (DPN) or estren (Es). E2 and
PPT increased OTR mRNA levels and decreased ERα and ERβ mRNA levels 3 and 6 h
posttreatment. DPN decreased ERα and ERβ mRNA levels at 3 and 6 h, while OTR mRNA levels
increased at 3 h and decreased at 6 h. OTR mRNA levels increased 3 h after the Es
treatment and then declined until 6 h. ERα and ERβ mRNA levels decreased by 3 h and
remained low until 6 h posttreatment with Es. The ER antagonist ICI182,780 (ICI)
suppressed the increases in OTR mRNA levels induced 3 h after the Es treatment. However,
ICI and tamoxifen (Tam) had no significant effect on ERα and ERβ mRNA levels in the
Es-treated or vehicle-treated group. In intact rats, proestrus-associated increases in OTR
mRNA levels were antagonized by both ICI and Tam. However, decreases in ERα and ERβ mRNA
levels were not antagonized by Tam and ICI, respectively. Therefore, uterine OTR gene
expression is upregulated by estrogen through the classical nuclear (or non-nuclear) ERs,
ERα and ERβ, while the levels of these ERs are downregulated by estrogen through multiple
pathways including Es-sensitive nonclassical ERs. 相似文献