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31.
背景与目的:外泌体是包含了复杂RNA和蛋白质的小膜泡,其中肿瘤细胞分泌的外泌体中的mRNA携带了大量肿瘤细胞遗传信息,因此对外泌体中特异性mRNA的分析,有望找到肿瘤诊断的新型分子标志物和治疗靶点。本研究通过高通量筛选与生物信息学方法探讨肝细胞癌(HCC)患者血清外泌体mRNA的表达特征及其潜在功能。方法:采集3例HCC患者及3例正常人的静脉血,用外泌体提取试剂盒提取血清外泌体,用Magen试剂盒提取外泌体RNA,对血清外泌体mRNA进行纯化、行反转录形成cDNA、PCR扩增、测序,最后将对所得数据质量进行评价后与参考数据进行比对,分析得到差异表达外泌体mRNA,并采用GO和KEGG通路富集分析对差异基因进行功能与通路注释。结果:与正常人比较,HCC患者有397个外泌体mRNA表达上调,192个外泌体mRNA表达下调;其中,NRGN、PF4、RGS18等17个基因表达明显上调,CXCL8、MORF4L2、SYCP1等14个基因显明显下调。GO富集分析显示,表达上调的外泌体mRNA的靶基因与蛋白质结合、蛋白质异二聚化活性、免疫系统过程的调节、胞外囊泡、细胞外细胞器、应激反应等有关,表达下调的外泌体mRNA的靶基因与嗅觉受体活性、细胞因子活性、CXCR趋化因子受体结合、中间丝、中间丝状细胞骨架等有关;KEGG通路分析显示,在上调的外泌体mRNA中,30条通路被显著富集,在下调的外泌体mRNA中9条通路被显著富集,其中,在上调的外泌体mRNA中,血小板激活、Rap 1信号通路、吞噬体、病毒致癌、肌动蛋白细胞骨架的调节与抗原处理和呈递等是最丰富和最有意义的通路;在下调的外泌体mRNA中,基础转录因子和细胞因子-细胞因子受体相互作用分别是最丰富和最有意义的通路。结论:HCC患者与正常人的血清外泌体mRNA表达特征存在较大差异,其与HCC发生、发展、转移可能密切相关,这为寻找新的诊断标志物及治疗靶点提供了依据。  相似文献   
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33.
目的:应用PEG 6000提取滑膜组织中外泌体并进行鉴定。方法:收集于北京中医药大学第三附属医院骨科行膝关节镜或关节置换手术过程中废弃的滑膜组织,用8%PEG 6000溶液对滑膜组织分泌的外泌体进行富集、提取,应用透射电镜(TEM)、纳米颗粒跟踪分析(NTA)、Western Blot对外泌体的形态、粒径大小以及标志蛋白CD9、CD63和Flotillin-1进行检测。结果:应用PEG 6000溶液可成功提取出富集类圆形、盘状囊泡的提取物,NTA鉴定显示粒径为(98.6±10.8)nm,Western Blot显示外泌体标志蛋白CD9、CD63和Flotillin-1均呈阳性高表达。结论:通过对提取物的形态、粒径大小以及标志蛋白分析证实PEG 6000从滑膜组织提取到的物质为外泌体,为以后研究滑膜组织外泌体的功能和机制提供了方法学基础。  相似文献   
34.
《Acta histochemica》2022,124(6):151931
ObjectiveTo investigate the role of exosomal miRNA-133 secreted by cardiac fibroblasts (CFs) in promoting cardiomyocyte differentiation.MethodsNeonatal rat CFs were cultured in vitro, and the cultured CFs were divided into three groups as follows: induction, miRNA-133 high expression, and miRNA-133 inhibition. miRNA-133 was transfected into CFs with lentivirus as a vector. CFs were transfected with the miRNA-133 inhibitor, and the markers of cardiomyocyte were detected through immunofluorescence staining, Western blotting, and real-time quantitative polymerase chain reaction (qRT-PCR) at 3, 8, and 14 days, respectively. The expression levels of cardiac troponin T (cTnT) and cardiac actin (α-actin) were determined, and qRT-PCR was used to detect the expression of miRNA-133 in the fibroblast exosomes.ResultsCFs subjected to immunofluorescence staining expressed vimentin and discoid domain receptor 2. The exosomes secreted by CFs were observed as small vesicles of 30–100 nm via transmission electron microscopy, and Western blotting was used to detect exosome-specific protein CD63 and CD9 expression. The expression levels of cTnT, α-actin, and exosomal miRNA-133 secreted into the supernatant of the miRNA-133 high-expression group increased gradually at different time points and reached the highest level at 14 days. The expression levels of cTnT, α-actin, and exosome miRNA-133 in the miRNA-133 inhibition group were the lowest.ConclusionThe exosomal miRNA-133, which is derived from CFs, can promote the differentiation of fibroblasts into cardiomyocyte-like cells.  相似文献   
35.
《Acta histochemica》2022,124(4):151896
Gastric ulcer is a common frequent clinical problem affecting all age and gender. This work aims to compare between the therapeutic effects of stem cell derived exosomes, stem cells conditioned medium and omeprazole on the healing of gastric ulcer model.Fifty rats were, assigned into 5 groups; control, gastric ulcer, omeprazole-treated, conditioned medium- treated, and exosomes-treated groups. Gastric ulcer was induced by aspirin dissolved in 1% carboxymethyl cellulose at a daily dose of 200 mg/kg for 5 consecutive days. Stomach specimens were obtained for histological, biochemical, and immunohistochemical assessments.The gastric ulcer group revealed widening of the fundic glands lumen containing, exfoliated dead cells. There was a remarkable distortion of the normal histological structure of the gastric mucosa with surface lining epithelial cell sloughing, vascular congestion and inflammatory cell infiltration. Both exosomes and conditioned medium treatments ameliorated almost all of the histopathological changes. Interestingly, the healing effect of exosomes was greater because it restored the histological architecture of gastric mucosa to nearly normal.In conclusion, this work may pave the future for using stem cell derived exosomes as a more convenient and effective adjuvant therapy in gastric ulcer.  相似文献   
36.
BackgroundBecause microvascular disease is one of the major drivers of diabetic complications, early detection of diabetic nephropathy (DN) by assessing the expression of exosomal microRNAs (miRNAs) in DN patients and healthy controls, may be of clinical value. The aim of this study wasto identify a novel miRNA panel of DN by combining bioinformatics analysis of miRNA databases and clinical verification to evaluate the significance of this panel as urine biomarkers for type 2 diabetic nephropathy (T2DN).Patients and MethodsPublic miRNA databases e.g miro-Ontology and miRWalk were analyzed and a novel panel of 3 microRNAs was retrieved. Meanwhile, combinatorial target prediction algorithms were applied. Multiple case-matched normal were examined by quantative RT-PCR for differential expression in urine exosomes from 210 participants, and the three identified miRNAs were validated as DN biomarkers.ResultsWe found urinary exosomalmiR-133b, miR-342, and miR-30a were expressed at significantly elevated levels in T2DN patients (P < 0.001) compared to normal. Furthermore, high-level expression of the 3 miRNAs was associated withHbA1c,systolic-diastolic blood pressure, LDL, serum creatinine, urinary albumin creatinine ratio and estimated glomerular filtration rate(eGFR). Moreover, 39.3%, 19.6% and 17.9% of patients with normo-albuminuria had positive (miR-133b, miR-342 and miR-30a, respectively); indicating the possibility of molecular changes in these patients before onset of albuminuria.ConclusionWe have identified novel urinary exosomal miRNA biomarkers of DN which were altered not only in micro and macroalbuminuric groups but also in some normoalbuminuria cases prior to albuminuria.  相似文献   
37.
目的 探讨结直肠癌(colorectal cancer,CRC)患者血浆外泌体中miR?590?3p的表达水平及其临床预后价值.方法 收集2015年1月至2015年12月于利川市人民医院、武汉大学中南医院住院并接受手术治疗的97例CRC患者以及20名健康对照者的血浆样本,采用ExoQuick Exosome Preci...  相似文献   
38.
Toxoplasmosis is a serious disease in humans and may cause abortion or congenital infection if a woman is exposed to the disease for the first time during pregnancy. Infection before pregnancy normally results in immunity protecting the foetus, suggesting that it may be possible to block vertical transmission of the parasite by appropriate vaccination before pregnancy. We found that the vaccination of CBA/J mice, before pregnancy, with exosomes secreted by SRDCs pulsed in vitro with Toxoplasma gondii-derived antigens (TAg) induced a protective response in the pups. Indeed, vaccination resulted in the presence of significantly fewer cysts in pup brains. This protection was associated with strong humoral responses in the serum in vivo. We also observed cellular responses in vivo, with cell proliferation associated with the production of cytokines by the splenocytes. Thus, exosomes are nucleic acid-free vesicles able to induce immune responses correlated with protection against T. gondii infection in a congenital model. They are therefore a potentially useful tool for vaccination against infectious disease.  相似文献   
39.
Cholangiocarcinoma (CCA) are a heterogeneous group of tumors in terms of aetiology, natural history, morphological subtypes, molecular alterations and management, but all sharing complex diagnosis, management, and poor prognosis. Several mutated genes and epigenetic changes have been detected in CCA, with the potential to identify diagnostic and prognostic biomarkers and therapeutic targets. Accessing tumoral components and genetic material is therefore crucial for the diagnosis, management and selection of targeted therapies; but sampling tumor tissue, when possible, is often risky and difficult to be repeated at different time points. Liquid biopsy (LB) represents a way to overcome these issues and comprises a diverse group of methodologies centering around detection of tumor biomarkers from fluid samples. Compared to the traditional tissue sampling methods LB is less invasive and can be serially repeated, allowing a real-time monitoring of the tumor genetic profile or the response to therapy. In this review, we analysis the current evidence on the possible roles of LB (circulating DNA, circulating RNA, exosomes, cytokines) in the diagnosis and management of patients affected by CCA.  相似文献   
40.
Exosomes are extracellular vesicles that express self-antigens (SAgs) and donor human leukocyte antigens. Tissue-specific exosomes can be detected in the circulation following lung, heart, kidney and islet cell transplantations. We collected serum samples from patients who had undergone lung (n?=?30), heart (n?=?8), or kidney (n?=?15) transplantations to isolate circulating exosomes. Exosome purity was analyzed by Western blot, using CD9 exosome-specific markers. Tissue-associated lung SAgs, collagen V (Col-V) and K-alpha 1 tubulin (Kα1T), heart SAgs, myosin and vimentin, and kidney SAgs, fibronectin and collagen IV (Col-IV), were identified using western blot. Lung transplant recipients diagnosed with bronchiolitis obliterans syndrome had exosomes with higher expression of Col-V (4.2-fold) and Kα1T (37.1-fold) than stable. Exosomes isolated from heart transplant recipients diagnosed with coronary artery vasculopathy had a 3.9-fold increase in myosin and a 4.7-fold increase in vimentin compared with stable. Further, Kidney transplant recipients diagnosed with transplant glomerulopathy had circulating exosomes with a 2-fold increased expression of fibronectin and 2.5-fold increase in Col-IV compared with stable. We conclude that circulating exosomes with tissue associated SAgs have the potential to be a noninvasive biomarker for allograft rejection.  相似文献   
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