首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
Recent progress in the accumulation of pig genomic information has enabled us to comprehensively explore polymorphisms in pig genes. One of our targets for exploration has been the genes encoding molecules related to pathogen recognition, such as pattern recognition receptors (PRRs). PRRs play a role in the innate immune system, and possess various members such as Toll-like receptors (TLRs), NOD-like receptors (NLRs), RIG-like helicases (RLHs), and C-type lectin-like receptors (CLRs). PRRs are required for the monitoring of pathogens; therefore, polymorphisms in PRRs may influence molecular functions such as ligand recognition. There have been many studies on the relationship between polymorphisms within PRR genes and disease susceptibility in humans and mice. Our studies have revealed that porcine PRR genes possess many nonsynonymous polymorphisms, particularly in regions encoding the ectodomains of TLRs localized on the cell surface. The genes encoding TLRs located on the membrane of intracellular compartments, and cytoplasmic PRRs such as NLRs and RLHs, also possessed nonsynonymous polymorphisms. Several observations indicate that there are relationships between polymorphisms in PRR or related genes and disease susceptibility in livestock animals including pig. Such information may contribute to breeding aimed at disease resistance, and effective vaccine design.  相似文献   

2.
固有免疫相关模式识别受体研究进展   总被引:2,自引:0,他引:2  
固有免疫是机体免疫系统防御微生物感染的第1道防线。模式识别受体(PRRs)中的Toll样受体(TLRs)、核苷酸寡聚结合域样受体(NLRs)和视黄酸诱导基因1样受体(RLRs)等识别不同或重叠的微生物组成成分,形成相应的信号转导产生免疫应答。近些年对于固有免疫相关PRRs的研究也取得了较大的进展,为免疫相关疾病的治疗提供了思路。本文对固有免疫相关PRRs的特征及不同PRRs的信号传导途径之间相互作用进行综述。  相似文献   

3.
Dendritic cells (DC) play a central role in tailoring the immune response to pathogens. Effector activity is mediated through pattern recognition receptors (PRRs) that recognize pathogen associated molecular patterns (PAMPS). C-type lectin receptors (CLR) comprise a group of PRRs that recognize a broad range of pathogens. CD209 (DC-specific ICAM3-grabbing non-integrin, DC-SIGN) is a CLR expressed on DC that plays a critical role on DC function and pathogen recognition. It facilitates DC migration to peripheral tissues and local lymph nodes and mediates T cell activation by binding ICAM-2 (CD102) and ICAM-3 (CD50). The absence of monoclonal antibody (mAb) to bovine CD209 has limited the ability to characterize the phenotype and function of DC in cattle. To address this issue we developed and used a mAb to CD209 to characterize the phenotype of CD209 expressing cells in bovine blood using flow cytometry. Initial analysis has revealed the CD209 positive population in blood is comprised of multiple phenotypically defined subsets.  相似文献   

4.
Gastrointestinal defence in the new-born is limited in comparison to adults, due to an immature epithelial barrier function and deficits in both innate and adaptive immune responses. Consequently, neonates (including foals) are at increased risk of disturbance to mucosal homeostasis during initial intestinal colonisation that may lead to excessive inflammation and bacterial translocation into the bloodstream, resulting in septicaemia. Bacterial recognition by Pattern Recognition Receptors (PRRs) and their downstream regulation of cytokine release have been shown to be pivotal for gastrointestinal mucosal homeostasis and the development of a functional intestinal barrier. Evidence suggests that selective PRR agonists limit the inflammatory responses and improve epithelial barrier function. Milk, and in particular colostrum, contain a broad array of oligosaccharides which seem to act as PRR agonists. This class of compounds forms a source for new dietary formulas that may orchestrate gut colonisation by the commensal flora in the early phase of life and so reduce the risks of inflammation and pathogen invasion.  相似文献   

5.
Antigen presenting cells (APCs), especially dendritic cells (DCs), play a crucial role in immune responses against infections by sensing microbial invasion through Toll-like receptors (TLRs). In this regard, TLR ligands are attractive candidates for use in humans and animal models as vaccine adjuvants. So far, no studies have been performed on TLR expression in non-human primates such as rhesus macaques. Therefore, we studied the TLR expression patterns in different subsets of APC in rhesus macaques and compared them to similar APC subsets in human. Also, expression was compared with corresponding DC subsets from different organs from mice. Here we show by semi-quantitative RT-PCR, that blood DC subsets of rhesus macaque expressed the same sets of TLRs as those of human but substantially differed from mouse DC subsets. Macaque myeloid DCs (MDCs) expressed TLR3, 4, 7 and 8 whereas macaque plasmacytoid DCs (PDCs) expressed only TLR7 and 9. Additionally, TLR expression patterns in macaque monocyte-derived dendritic cells (mo-DCs) (i.e., TLR3, 4, 8 and 9), monocytes (i.e., TLR4, 7, and 8) and B cells (i.e., TLR4, 7, 8, and 9) were also similar to their human counterparts. However, the responsiveness of macaque APCs to certain TLR ligands partially differed from that of human in terms of phenotype differentiation and cytokine production. Strikingly, in contrast to human mo-DCs, no IL-12p70 production was observed when macaque mo-DCs were stimulated with TLR ligands. In addition, CD40 and CD86 phenotypic responses to TLR8 ligand (poly U) in mo-DCs of macaque were higher than that of human. Despite these functional differences, our results provide important information for a rational design of animal models in evaluating TLR ligands as adjuvant in vivo.  相似文献   

6.
Pattern-recognition receptors (PRRs) are important components of the innate immune system, enabling early detection of infection. Defective PRR function has been implicated in several infectious and immune-mediated diseases of human beings, including Crohn's disease (CD). Anal furunculosis (AF) is an immune-mediated disease which primarily occurs in German shepherd dogs (GSD) and could result from a similar type of PRR dysfunction. The aim of the current study was to investigate canine PRR responses in vitro and to test the hypothesis that these were altered in AF-affected GSD. The pattern-recognition receptors TLR1, TLR2, TLR4, TLR6, TLR9, NOD1 (nucleotide-binding oligomerisation domain) and NOD2 were evaluated in the DH82 canine monocyte/macrophage cell line. These cells were found to express mRNA for all the selected PRRs with TLR2 mRNA the most and TLR5 mRNA the least abundant. A similar pattern of expression was found in canine blood-derived monocyte/macrophages. Stimulation of DH82 cells and blood-derived monocyte/macrophages using specific PRR-ligands, resulted in expression of pro-inflammatory cytokine mRNA. Quantification of TNFalpha mRNA and protein secretion from stimulated cells demonstrated variable responses with lipopolysaccharide (TLR4 ligand) and PAM(3)CSK4 (TLR1/2 ligand) proving to be the most potent and CpG DNA (TLR9 ligand) the least potent. Comparing PRR responses in blood-derived monocyte/macrophages from healthy blood-donor dogs with those from AF-affected GSD showed a deficiency in the latter in response to LD-MDP (NOD2 ligand) at the mRNA level but not at the protein level. It is possible that dysfunctional NOD2 responses by cells of the monocyte/macrophage lineage are involved in the pathogenesis of AF.  相似文献   

7.
易丹  王博  段慧荣  李毅  王丽蓉 《草地学报》2021,29(3):443-456
为探明白刺(Nitraria tangutorum)14-3-3基因家族的基本特征及其进化关系,本研究基于白刺转录组数据,利用生物信息学方法,对白刺14-3-3基因家族成员进行鉴定,预测其理化性质、亚细胞定位、保守结构域,分析其系统进化关系及其基因在不同浓度盐、干旱处理下的组织器官表达模式.结果表明:从白刺转录组数据中...  相似文献   

8.
Pattern recognition receptors (PRRs) on host cells detect pathogens to activate innate immunity which, in turn, initiates inflammatory and adaptive immune responses. Successful activation of PRRs is, therefore, critical to controlling infections and driving pathogen-specific adaptive immunity, but overactivity of PRRs causes systemic inflammation, which is detrimental to the host. Here we review the PRR literature as it relates to horses and speculate on the role PRRs may play in sepsis and endotoxaemia.  相似文献   

9.
机体识别病毒核酸的几种分子模式及途径   总被引:2,自引:1,他引:2  
近些年机体病原相关模式受体及其识别分子机制的研究,极大地促进了先天性分子免疫学的发展,并成为现代免疫学研究的重点和热点领域。作者通过机体识别病毒核酸的Toll样受体(Toll-like receptors,TLRs)、RIG-I样受体(RIG-I like receptors,RLRs)、NOD样受体(NOD-like receptors,NLRs)和DAI(DNA-dependent activatorof interferon-regulatory factors,DAI)等模式识别分子的细胞定位、分子结构及其识别病毒核酸途径的介绍,系统、全面地探讨了宿主机体如何全方位识别和消除入侵病毒的分子免疫防御途径,为抗病毒药物和疫苗的设计以及抗病育种提供了理论依据。  相似文献   

10.
Dendritic cells (DC) in peripheral tissues are considered as immature cells that mature and migrate towards lymph nodes upon stimulation with pathogens. This commonly accepted paradigm is challenged by the fact that tolerance to peripheral self antigen is controlled by mature DC and that DC collected from afferent lymph draining different tissues from several species, in the absence of pathogen signaling, were inconsistently found to be either at a mature or semi-mature state. In order to better define the maturation state of DC that migrate in lymph in absence of pathogen stimulation, we compared skin lymph DC to resident and LPS (lipopolysaccharide)-activated skin DC thanks to the establishment of a mini-pig model of lymph duct cannulation. Based on their co-stimulatory molecules expression and endocytotic capacities, pig lymph skin DC were found at an intermediate state of maturation between resident and LPS-activated skin DC and were fully capable of allogeneic T cell stimulation. Furthermore, lymph skin DC could be further matured by LPS or influenza stimulation. Thus, using the pig skin model which is relevant to human, we show that skin-derived DC constantly migrate at an intermediate state of maturation that can be further enhanced upon appropriate stimulation.  相似文献   

11.
The study was aimed to research the effects of Oxytropis glabra DC (O.glabra DC) poisoning on reproductive organs coefficent, reproductive performance and related gene expression in Hetian sheep ewes. The sera, hypothalamus, pituitary and ovary of Hetian sheep ewes cases poisoning of O. glabra DC were collected, the organ exponent and contents of GnRH, FSH, LH, E2 and P4 in serum were measured, then the mRNA expression of reproductive genes were measured. The result demonstrated that the index of hypothalamus, pituitary and ovary were extremely significantly higher than normal sheep (P < 0.01),the follicle number on the surface of the ovaries in poisoning groups were significantly lower than normal sheep (P < 0.05). The result of hematoxylin-eosin staining showed that the nuclear of neuronal cells in hypothalamus were pyknosis and hyperchromatic; The nuclear of cells in pituitary deformation and hyperchromatic, cytoplasm decreased; The primary oocyte in ovary dissolved, disappeared, interstitial blood vessel expanded. The content of GnRH, FSH, LH, E2 and P4 in serum in poisoned Hetian sheep ewes were extremely significantly lower than normal sheep (P < 0.01). The mRNA expression levels of Kiss-1, GPR54, ERα in hypothalamus, GnRHR in pituitary and FSHR and LHR in ovary were extremely significantly lower than normal sheep (P < 0.01). The result showed that O. glabra DC poisoning could affect Hetian sheep ewes reproductive system by affecting microstructure and ultrastructure of hypothalamus-pituitary-ovarian axis.  相似文献   

12.
试验旨在探讨小花棘豆(Oxytropis glabra DC)中毒对和田羊母羊繁殖器官指数、性激素水平和相关基因mRNA表达量的影响。以小花棘豆中毒和田羊母羊为研究对象,采集血清后屠宰,采集试验羊的丘脑、垂体和卵巢组织,测定其脏器系数,检测血清中促性腺激素释放激素(GnRH)、促卵泡素(FSH)、促黄体素(LH)、雌二醇(E2)和孕酮(P4)含量的变化,并检测各组织中相关繁殖基因的表达。结果显示,小花棘豆中毒和田羊母羊丘脑、垂体和卵巢指数均极显著升高(P < 0.01),且卵巢表面卵泡数显著下降(P < 0.05),HE染色表明丘脑神经元细胞固缩、浓染;垂体中细胞核变形、浓染,胞浆减少;卵巢中初级卵母细胞溶解、消失,间质血管扩张。小花棘豆中毒和田羊母羊血清中GnRH、FSH、LH、E2和P4含量均极显著下降(P < 0.01),丘脑中Kiss-1、GPR54、ERα mRNA,垂体中GnRHR mRNA和卵巢中FSHR、LHR mRNA表达量均极显著下降(P < 0.01)。结果表明,小花棘豆毒性成分可通过丘脑-垂体-性腺轴影响和田羊母羊的生殖系统。  相似文献   

13.
A critical component of host innate immunity is recognition of pathogen-associated molecular patterns (PAMPs) by pattern recognition receptors (PRRs). Dectin-1 is the primary PRR for exogenous beta-glucan, a component of fungal and bacterial cell walls. A previous study conducted in our laboratory demonstrated that administration of beta-glucan as a feed additive resulted in increased innate immune function of neonatal chickens, suggesting that chickens possess a Dectin-1-like beta-glucan receptor. In the present study, we demonstrated that heterophils and peripheral blood mononuclear cells (PBMCs) from day-old chicks had a significant increase in the generation of reactive oxygen species (ROS) following stimulation with the Dectin-1 specific agonist, curdlan. Pretreatment of heterophils and PBMCs with laminarin, a beta-glucan receptor blocking agent and specific inhibitor of Dectin-1 activity, significantly reduced the curdlan-induced ROS production. Together these data provide evidence for the first time of the presence of a functional Dectin-1-like beta-glucan receptor in chicken heterophils and PBMCs.  相似文献   

14.
In order to study the defensive role and action mechanism of antibacterial peptide NK-Lysin during body reaction, when pathogen infect animal body. This study detected the expression of NK-Lysin induced by different concentrations of lipopolysaccharide(LPS) and in different immune organs by Real-time fluorescence quantitative PCR, and explored the generation and response of sheep antimicrobial peptide NK-Lysin in immune organs. The cloning vector of target gene NK-Lysin and reference gene GAPDH were constructed, drew the standard curve and detected the expression of NK-Lysin. The results showed that inducing with the LPS concentrations of 0.01, 0.1, 1 and 10 μg/mL, respectively,the expression of NK-Lysin reached the maximum within 8 h. There was no positive correlation between the expression of NK-Lysin and concentration of LPS. The expression of NK-Lysin mRNA had varying degrees in pre-shoulder lymph, spleen and blood. The expression in spleen was extremely significantly different compared with other organs(P<0.01). Immune organs could express the antimicrobial peptide NK-Lysin in a relatively short time, and NK-Lysin participated in the body’s innate immunes responses.  相似文献   

15.
本研究旨在克隆绵羊角蛋白关联蛋白8.2(keratin-associated protein,KAP8.2)基因mRNA并分析该基因在不同组织器官的表达分布。首先提取小尾寒羊与新吉细毛羊皮肤及不同组织总RNA,RT-PCR方法克隆KAP8.2基因并进行两个品种间的比较分析,实时荧光定量PCR方法分析两个品种间KAP8.2基因的表达谱差异。结果表明已成功克隆出绵羊KAP8.2基因mRNA,该片段长574 bp,其中ORF区192 bp,编码63个氨基酸,甘氨酸(Gly)和酪氨酸(Tyr)含量依次为23.8%和20.6%,属于典型的HGT-KAP家族。多态性分析显示新吉细毛羊与小尾寒羊KAP8.2基因间存在丰富的多态性,多态位点多位于CDS区两侧,其中小尾寒羊KAP8.2基因3'UTR区c192+19-39出现一个疑似fru-let-7j的作用靶位。不同组织表达谱分析显示该基因为多组织表达基因,但两个品种羊不同组织表达谱存在较大差异,表现为小尾寒羊在脾脏、肝脏和皮肤中高表达,而新吉细毛羊则在皮肤和心脏中高表达。本研究提示小尾寒羊与新吉细毛羊KAP8.2基因在基因多态性还是组织表达分布上存在显著差异,提示该基因与毛表型性状相关。  相似文献   

16.
Multidrug resistance 1 (MDR1) and multidrug resistance-associated protein 2 (MRP2) are two prominent members of the super-family of ATP-binding cassette (ABC) transporters that carry a wide range of substrates across biological membranes, using ATP as energy source. The level of expression of these efflux transporters in different tissues has hitherto been studied mainly in mammals, and only P-glycoprotein (P-gp), the product of the MDR1 gene, has been described in chickens as of yet. The aim of this study was to describe the levels of expression of MDR1 and MRP2 mRNAs in different tissues of chickens, as these transporters play an important role in the absorption, distribution and excretion of drugs and toxins.In the gastro-intestinal tract, the highest levels of MDR1 mRNA expression were found in the small intestines, followed by the colon, whereas lower levels were found in the crop, proventriculus and the caeca. High MDR1 expression was also measured in the excretory organs such as liver, kidney and lungs. In contrast to rodents and humans, relatively low levels were found in the adrenals and in the immature sex organs such as testicles and ovaries.MRP2 mRNA expression was high in the liver, kidneys, duodenum and the jejunum, but expression was low in the ileum as well as in the lungs. No MRP2 expression could be detected in the other organs tested. Comparing the findings in chickens with previously published data, in particular those from humans and rodents, an unexpected high degree of similarity in the expression pattern of MDR1 and MRP2 mRNAs was apparent.  相似文献   

17.
Dendritic cells (DCs) act as antigen presenting cells that bridge innate and adaptive immune systems with the unique capacity to initiate primary T-cell responses and efficiently stimulate memory responses. In pig, little information is available about these cells in secondary lymphoid organs, the place where T cell activation usually occurs. As increased knowledge on DC is a necessary prerequisite to further understand their role in response to microbial infection or in protection after vaccination, we investigated the DC types that would be present in tonsil, spleen and non-subcutaneous lymph nodes in the steady state. One population was composed of CD172a(+)CD11R1(+)CD1(+/-)CD80/86(+/-) cells and would correspond to conventional DCs (cDC), while the other one was composed of CD172a(+)CD4(+)CD1(+/-)CD80/86(+/-) cells and would correspond to plasmacytoid DCs (pDC). These subsets were also detected in blood but spleen was the tissue with the higher frequency of such DCs. In lymphoid organs, most of cDC and pDC were in an immature status, as revealed by the low percentage of cells expressing the co-stimulatory molecule CD80/86. However, expression of that marker by 5% of DCs in organs and up to 15% in blood, together with lower expression of CD1a and expression of CD208, would indicate a partial activation and/or semi-maturation. Interestingly, 8% of tonsil pDC and 15% of blood pDC were shown to secrete IFN-alpha, while 18-20% of cDC expressed TNF-alpha in these tissues. Both cell types also expressed IL-12 and IL-10 in the steady state. Measurements of IFN-alpha, TNF-alpha, IL-12 and IL-10 levels in serum confirmed their production within immune homeostasis, whereas IL-6, IL-18 and IFN-gamma could not be detected. Altogether, these data complete knowledge on porcine immune system cells and will be a useful tool for further in vivo studies on porcine DC role in peripheral tolerance induction and in immune responses to pathogens.  相似文献   

18.
19.
轮状病毒(RV)是引起婴幼儿、幼畜禽急性肠胃炎的人畜共患病原,常与其他病原体混合感染,多以呕吐,严重水样腹泻,脱水为临床症状,感染后具有较高病死率,对人类公共卫生以及养殖业造成极大危害.RV病原相关分子模式(PAMP)可被肠上皮细胞(IECs)中一组可遗传的模式识别受体(PRR)识别,通过IECs、先天免疫细胞与RV互...  相似文献   

20.
The availability of a panel of monoclonal antibodies to sheep MHC class I and class II gene products has allowed for the first time an assessment of the relative complexity of the sheep MHC. By using four monoclonal antibodies to MHC class I, and seven monoclonal antibodies to MHC class II molecules together with one-dimensional SDS-PAGE, sequential immunoprecipitation and 2-dimensional gel analysis, three class I gene products and four distinct subsets of class II molecules have been identified. Sheep class I molecules showed heterogeneity on 2-dimensional gels and as in mouse and man, represented the products of at least three different non-allelic class I genes. Interestingly, the sheep beta 2 microglobulin molecule also displayed heterogeneity, consistent with either two primary gene products or allelic variation. Four sheep class II monoclonal antibodies identified distinct, non-overlapping subsets of sheep class II molecules of Mr 32-36 K (alpha chain) and 25-28 K (beta chain). These class II molecules were co-expressed on sheep B lymphocytes and represented the primary products of different sheep MHC class II genes. The class II molecules within three of these subsets displayed allelic polymorphism essentially restricted to their beta polypeptides, while the fourth subset of class II molecules showed allelic variation in both their alpha and beta polypeptides. The results of this study represent the first evidence for gene duplication and heterogeneity within the sheep MHC. The identification of three primary class I gene products and four distinct subsets of class II molecules suggests three class I loci and up to four distinct class II subregions within the sheep MHC. Potentially large numbers of allelic variants of these different gene products may be expressed in normal sheep.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号