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1.
《Molecular therapy》2022,30(8):2856-2867
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2.
BackgroundIn the field of transplantation, inducing immune tolerance in recipients is of great importance. Blocking co-stimulatory molecule using anti-CD28 antibody could induce tolerance in a rat kidney transplantation model. Myeloid-derived suppressor cells (MDSCs) reveals strong immune suppressive abilities in kidney transplantation. Here we analyzed key genes of MDSCs leading to transplant tolerance in this model.MethodsMicroarray data of rat gene expression profiles under accession number GSE28545 in the Gene Expression Omnibus (GEO) database were analyzed. Running the LIMMA package in R language, the differentially expressed genes (DEGs) were found. Enrichment analysis of the DEGs was conducted in the Database for Annotation, Visualization and Integrated Discovery (DAVID) database to explore gene ontology (GO) annotation and their Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. Their protein-protein interactions (PPIs) were provided by STRING database and was visualized in Cytoscape. Hub genes were carried out by CytoHubba.ResultsThree hundred and thirty-eight DEGs were exported, including 27 upregulated and 311 downregulated genes. The functions and KEGG pathways of the DEGs were assessed and the PPI network was constructed based on the string interactions of the DEGs. The network was visualized in Cytoscape; the entire PPI network consisted of 192 nodes and 469 edges. Zap70, Cdc42, Stat1, Stat4, Ccl5 and Cxcr3 were among the hub genes.ConclusionsThese key genes, corresponding proteins and their functions may provide valuable background for both basic and clinical research and could be the direction of future studies in immune tolerance, especially those examining immunocyte-induced tolerance.  相似文献   
3.
Discoid lupus erythematosus (DLE) is the most common skin manifestation of lupus; however, the molecular mechanisms underlying DLE remain unknown. Therefore, we aimed to identify key differentially expressed genes (DEGs) in discoid lupus skin and investigate their potential pathways.To identify candidate genes involved in the occurrence and development of the disease, we downloaded the microarray datasets GSE52471 and GSE72535 from the Gene Expression Database (GEO). DEGs between discoid lupus skin and normal controls were selected using the GEO2R tool and Venn diagram software (http://bioinformatics.psb.ugent.be/webtools/Venn/). The Database for Annotation, Visualization, and Integrated Discovery (DAVID), Enrichr, and Cytoscape ClueGo were used to analyze the Kyoto Encyclopedia of Gene and Genome pathways and gene ontology. Protein-protein interactions (PPIs) of these DEGs were further assessed using the Search Tool for the Retrieval Interacting Genes version 10.0.Seventy three DEGs were co-expressed in both datasets. DEGs were predominantly upregulated in receptor signaling pathways of the immune response. In the PPI network, 69 upregulated genes were selected. Furthermore, 4 genes (CXCL10, ISG15, IFIH1, and IRF7) were found to be significantly upregulated in the RIG-I-like receptor signaling pathway, from analysis of Enrichr and Cytoscape ClueGo.The results of this study may provide new insights into the potential molecular mechanisms of DLE. However, further experimentation is required to confirm these findings.  相似文献   
4.
背景:随着疾病治疗模式的改变,人们已经意识到中医药在激素性股骨头坏死治疗过程中的重要性,因此利用生物信息学从分子水平分析激素性股骨头坏死的发病机制,构建疾病风险模型,并预测具有潜在治疗作用的中药,为后期中医药治疗激素性股骨头坏死提供一定的理论依据。目的:基于生物信息学挖掘激素性股骨头坏死的竞争性内源RNA(ceRNA)调控网络,分析其在激素性股骨头坏死中的分子调控机制,预测相关疾病靶点并构建疾病风险模型,同时预测具有潜在治疗作用的中药。方法:检索GEO数据库,下载激素性股骨头坏死的矩阵文件GSE123568和基因注释文件GPL15207。借助R语言等软件分析得到差异表达的长链非编码RNA与mRNA,并通过公共数据库预测与差异表达长链非编码RNA关联的miRNA-mRNA,再将预测到的mRNA与差异表达mRNA取交集,整合得到ceRNA网络。随后采用STRING数据库和Cytoscape软件筛选关键基因,利用R语言分析关键基因的功能与相关通路,并挖掘关键ceRNA网络。最后根据关键基因构建激素性股骨头坏死的风险模型,并进行中药预测。结果与结论:(1)与健康对照相比,激素性股骨头坏死患者共有7个长链非编码RNA和1763个mRNAs存在差异表达;(2)筛选出STAT3、KAT2B、AGO4、JAK2、JAK1、PTGS2共6个关键基因;(3)关键基因所富集的功能包括对肽激素的反应、白细胞介素6介导的信号通路、细胞对白细胞介素6的反应等生物学过程,涉及JAK-STAT、脂肪细胞因子、催乳素等信号通路;(4)4种mi RNAs(mi R-135a-5p、mi R-137、mi R-17-5p、miR-20b-5p)和2种长链非编码RNA(SNHG11、C20orf197)可能在导致激素性股骨头坏死发生发展过程中发挥关键作用;(5)KAT2B最有可能是激素性股骨头坏死发生发展的风险因子;(6)郁金、淫羊藿、黄芪具备治疗激素性股骨头坏死疾病靶点的可能。通过对激素性股骨头坏死相关长链非编码RNA介导的ceRNA网络进行分析,识别出潜在的疾病靶点、信号通路及潜在治疗中药,为进一步阐明其发病机制,并为后续的实验研究提供参考依据。  相似文献   
5.
急性白血病的基因表达谱分析与亚型分类特征的鉴别   总被引:7,自引:0,他引:7  
本研究基于生物信息学理论,运用模式识别方法和计算技术,对急性白血病的基因表达谱数据进行分析,研究急性白血病的亚型识别与分类信息基因选取问题。首先去除无关基因,然后利用浮动顺序搜索算法搜索特征空间生成候选特征子集,最后以支持向量机作为分类器进行急性白血病的亚型识别,并以误识率为依据鉴别出了5个包含完整分类信息的基因。实验结果表明,本研究鉴别出的5个信息基因能以100%的正确率准确识别急性白血病亚型。  相似文献   
6.
The development of the human immune system during embryonic and fetal life has historically been difficult to research due to limited access to human tissue. Experimental animal models have been widely used to study development but cellular and molecular programmes may not be conserved across species. The advent of multiomic single-cell technologies and an increase in human developmental tissue biobank resources have facilitated single-cell multiomic studies focused on human immune development. A critical question in the near future is "How do we best reconcile scientific findings across multiple omic modalities, developmental time, and organismic space?" In this review, we discuss the application of single-cell multiomic technologies to unravel the major cellular lineages in the prenatal human immune system. We also identify key areas where the combined power of multiomics technologies can be leveraged to address specific immunological gaps in our current knowledge and explore new research horizons in human development.  相似文献   
7.
人CD226基因SNP和启动子序列分析   总被引:6,自引:0,他引:6  
目的 研究人CD226(PTA1)启动子及其5‘上游调控序列。方法 应用计算机软件预测启动子序列,并分析人CD226基因5‘上游调控序列以及通过RT-PCR的方法研究开放读框中的单核苷酸多态性。结果 CD226基因在-375bp处和-130bp处可能有两个启动子,含有AP-1,Ets-1,Spl,P300,PU.1,PEA3等转录因子结合序列,在编码胞浆区的序列中存在一个单核苷酸多态性位点。结论 CD226基因表达受到多种转录因子和5‘端上游调控序列的调控。  相似文献   
8.
目的从华支睾吸虫全长cDNA质粒文库中识别ATP合酶B亚基,利用生物信息学方法预测其结构和功能特征,用以指导实验研究。方法利用生物信息学网站的各种在线分析工具和Vector NT Isuite软件包,识别华支睾吸虫ATP合酶B亚基基因并预测编码蛋白质的各种结构与功能特征,并根据该基因构建种系分子进化树。结果Blastx分析该基因为全长基因,属于ATP合酶B亚基家族,其分子进化树与种系进化过程非常吻合。该基因全长1008bp,编码300个氨基酸,含有线粒体转运肽、两个跨膜区、一个核定位序列和多个磷酸化位点,具有较稳定的理化性质。结论ATP合酶B亚基是一个理想的真核种系进化的分子标志。华支睾吸虫ATP合酶B亚基具有线粒体和细胞核的双重定位序列,提示该蛋白可能在华支睾吸虫的能量代谢途径中发挥独特的调节作用。  相似文献   
9.
Advances in sequencing and genotyping technologies over the last decade have enabled geneticists to easily characterize genetic variation at the nucleotide level. Hundreds of genes harboring mutations associated with genetic disease have now been identified by positional cloning. Using variation at closely linked genetic markers, it is possible to predict the times in the past at which particular mutations arose. Such studies suggest that many of the rare mutations underlying human genetic disorders are relatively young. Studies of variation at genetic markers linked to particular mutations can provide insights into human geographic history, and historical patterns of natural selection and disease, that are not available from other sources. We review two approaches for estimating allele age using variation at linked genetic markers. A phylogenetic approach aims to reconstruct the gene tree underlying a sample of chromosomes carrying a particular mutation, obtaining a “direct” estimate of allele age from the age of the root of this tree. A population genetic approach relies on models of demography, mutation, and/or recombination to estimate allele age without explicitly reconstructing the gene tree. Phylogenetic methods are best suited for studies of ancient mutations, while population genetic methods are better suited for studies of recent mutations. Methods that rely on recombination to infer the ages of alleles can be fine‐tuned by choosing linked markers at optimal map distances to maximize the information available about allele age. A limitation of methods that rely on recombination is the frequent lack of a fine‐scale linkage map. Maximum likelihood and Bayesian methods for estimating allele age that rely on intensive numerical computation are described, as well as “composite” likelihood and moment‐based methods that lead to simple estimators. The former provide more accurate estimates (particularly for large samples of chromosomes) and should be employed if computationally practical. Hum Mutat 18:87–100, 2001. © 2001 Wiley‐Liss, Inc.  相似文献   
10.
Intermittent fasting and fasting mimetic diets ameliorate inflammation. Similarly, serum extracted from fasted healthy and asthmatic subjects’ blunt inflammation in vitro, implicating serum components in this immunomodulation. To identify the proteins orchestrating these effects, SOMAScan technology was employed to evaluate serum protein levels in healthy subjects following an overnight, 24-h fast and 3 h after refeeding. Partial least square discriminant analysis identified several serum proteins as potential candidates to confer feeding status immunomodulation. The characterization of recombinant IGFBP1 (elevated following 24 h of fasting) and PYY (elevated following refeeding) in primary human CD4+ T cells found that they blunted and induced immune activation, respectively. Furthermore, integrated univariate serum protein analysis compared to RNA-seq analysis from peripheral blood mononuclear cells identified the induction of IL1RL1 and MFGE8 levels in refeeding compared to the 24-h fasting in the same study. Subsequent quantitation of these candidate proteins in lean versus obese individuals identified an inverse regulation of serum levels in the fasted subjects compared to the obese subjects. In parallel, IL1RL1 and MFGE8 supplementation promoted increased CD4+ T responsiveness to T cell receptor activation. Together, these data show that caloric load-linked conditions evoke serological protein changes, which in turn confer biological effects on circulating CD4+ T cell immune responsiveness.  相似文献   
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