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排序方式: 共有285条查询结果,搜索用时 15 毫秒
1.
目的 通过建立毛囊蠕形螨与 HaCaT 细胞共培养体系,探讨毛囊蠕形螨与细胞表达 TLR2 以及炎症相 关基因之间的关联性。 方法 用 10 只、30 只、50 只毛囊蠕形螨和空白对照分别与 HaCaT 细胞共培养 24 h,提取细胞 RNA,反转录成 cDNA;设计特异性引物,对 TLR2 以及相关的 KLK5、IL-1β、IL-6、IL-8 和 CCL2 等炎性因子进行常 规 PCR 扩增、克隆和测序;采用 qRT-PCR 检测表达量,比较与螨虫数之间的关联性。 结果 琼脂糖凝胶电泳显示 PCR 产物为单一清晰条带,序列大小与模板一致,表明引物特异性好。 qRT-PCR 检测显示,除 10 只螨虫组与空白 组差异均无统计学意义外(t = 0. 00~ 2. 25,P>0. 05),TLR2 和 IL-6 在 30 只和 50 只螨虫组与空白组差异有统计学意 义(TLR2:t = 6. 54 和 10. 85;IL-6:t = 14. 35 和 17. 52,P<0. 001),且 50 只螨虫组上调明显大于 30 只螨虫组;IL-8、 CCL2 和 KLK5 在 30 只和 50 只螨虫组与空白组的差异也有统计学意义( IL-8:t = 5. 34 和 6. 98;CCL2:t = 3. 12 和 4. 03;KLK5:t = 3. 31 和 4. 05,P<0. 05),但 30 只与 50 只螨虫组的差异无统计学意义;而 IL-1β 只在 50 只螨虫组与 空白组的差异有统计学意义(t = 2. 60,P<0. 05),30 只螨虫组与空白组的差异无统计学意义。 HaCaT 细胞 TLR2 的 表达与蠕形螨虫数呈正相关 (r = 0. 984),与 TLR2 调控的炎性因子 IL-6、IL-8、CCL2、KLK5 和 IL-1β 的表达也呈正 相关(r= 0. 970、0. 984、0. 985、0. 974 和 0. 938),尤其是 TLR2 和 IL-6 表达量变化最明显。 结论 本研究成功构建了 毛囊蠕形螨与 HaCaT 细胞共培养体系,首次从细胞水平揭示皮肤免疫反应与蠕形螨感染数量有关,这一探索性研究 结果对于揭示蠕形螨寄生诱发面部皮肤损害的分子机制具有重要的科学意义。  相似文献   
2.
【摘要】 目的:探讨人髓核细胞(NPCs)诱导对人尿源性干细胞(USCs)向髓核样细胞分化的作用。方法:手术时获取腰椎间盘突出症患者L4/5的髓核组织,并采用贴壁法体外分离培养NPCs;从健康成年人尿液中获取USCs并进行体外培养,通过倒置显微镜观察细胞形态,并采用成骨、成脂、成软骨三系诱导分化及蛋白免疫印迹技术(Western blot,WB)对所获取的USCs进行形态、分化潜能及细胞表面标志蛋白鉴定。使用Transwell小室将P3代NPCs与USCs培养以建立共培养体系,设实验组、对照组及NPCs组,实验组为NPCs与USCs共培养组,对照组为单独USCs培养,NPCs组为单独NPCs培养;培养14d后应用倒置显微镜观察细胞形态;应用定量实时聚合酶链反应(qRT-PCR)及WB分别检测实验组USCs、对照组USCs与NPCs组NPCs中蛋白多糖(ACAN)、SOX-9(SRY-related high mobility groupbox gene 9)、Ⅱ型胶原(COL2)及缺氧诱导因子1α(HIF-1α)的mRNA及蛋白的表达情况;免疫荧光染色观察3组 COL2A1及ACAN荧光表达。结果:培养的USCs成骨、成脂、成软骨三系分化实验结果均为阳性;USCs中干细胞阳性标志物CD29、CD44、CD73和CD90呈高表达,未检出干细胞阴性标志物CD34和CD45。培养14d后倒置显微镜下对照组及NPCs组细胞形态无变化,实验组USCs向髓核样细胞分化,形态变化明显。经共培养诱导14d后实验组及NPCs组中的ACAN、SOX-9、COL2A1及HIF-1α基因mRNA及蛋白表达均显著高于对照组(P<0.05),ACAN及COL2A1荧光强度明显高于对照组;实验组上述各种mRNA及蛋白表达与NPCs组比较均无统计学差异(P>0.05),实验组荧光强度与NPCs组比较无明显差异。结论:在体外实验中,人NPCs可通过共培养的方式诱导人USCs分化为髓核样细胞,可为椎间盘组织工程研究提供NPCs来源。  相似文献   
3.
目的:观察7-二氟亚甲基-5,4-二甲氧基异黄酮(DFMG)是否能干预损伤内皮细胞对平滑肌细胞增殖和迁移的促进作用,且其干预过程是否与 TLR4信号通路相关。方法:采用 CCK-8法和 Transwell 迁移法测定LPC 诱导的内皮细胞的损伤对平滑肌细胞的增殖和迁移的影响。采用 Western blot 和荧光定量 PCR 测定损伤共培养体系中的内皮细胞 TLR4在蛋白水平和基因水平的表达。运用 TLR4特异性激动剂(LPS)和特异性的抑制剂(CLI095),采用 CCK8法和 Transwell 迁移法测定损伤共培养体系中平滑肌细胞的增殖能力和迁移能力。结果:①随着 LPC 浓度的增加,LPC 诱导的内皮细胞损伤引起平滑肌细胞的增殖和迁移的效应增强,并且选取30μM 的LPC 作用于内皮细胞并与平滑肌细胞共培养作为实验的损伤共培养模型。②经光密度值分析,LPC 组的内皮细胞TLR4的表达量是对照组的2倍;经荧光定量 PCR 分析,LPC 组的内皮细胞 TLR4的表达量是对照组的2.414倍。③相比,损伤组和 LPS 组的平滑肌细胞的增殖和迁移能力较对照组更强;相比,CLI095组和 DFMG 组的平滑肌细胞的增殖和迁移能力较损伤组更弱。结论:LPC 诱导的内皮细胞的损伤可以引起平滑肌细胞的增殖和迁移,而DFMG 可能是通过抑制 TLR4信号阻碍损伤的内皮细胞对平滑肌细胞增殖和迁移的促进作用。  相似文献   
4.
目的 探索骨髓间充质干细胞(bone mesenchymal stem cells,BMSCs)对子宫内膜癌Ishikawa细胞转录水平的影响。方法 用Lenti-EGFP慢病毒感染Ishikawa细胞,分别将表达增强型绿色荧光蛋白(enhanced green fluorescent protein,EGFP)的Ishikawa细胞单独培养、与BMSCs接触共培养;通过流式细胞术分离Ishikawa细胞,并进行转录组测序分析筛选差异表达的mRNA和miRNA,通过miRWalk预测差异miRNA靶基因,对两者的交集基因进行GO、KEGG、蛋白网络互作分析;采用qRT-PCR和Western blot验证测序结果的准确性。结果 标记EGFP的Ishikawa细胞与BMSCs共培养后,分离出的Ishikawa-EGFP阳性细胞占33.6%,阴性细胞占10.5%。测序后共筛选出5 928个差异表达mRNA和111个差异表达miRNA。蛋白网络互作分析显示交集基因表达的蛋白之间相互作用,核心节点包括CDKN1A、JAK1、COL1A1、VCAN等。miRNA-mRNA网络图显示CDKN1A与hsa-let-7e-5p存在潜在靶向关系。GO分析和KEGG分析结果显示,其交集基因参与细胞外基质结构、细胞黏附分子结合等,并主要富集在PI3K-Akt、黏着斑、MAPK、EGFR酪氨酸激酶抑制剂耐药等信号通路。qRT-PCR和Western blot结果显示,共培养后Ishikawa-EGFP细胞中CDKN1A表达上调,hsa-let-7e-5p表达下调。结论 BMSCs可能通过细胞间的相互作用调节肿瘤局部微环境并促进子宫内膜癌的发生发展。  相似文献   
5.
Cell-cell interactions are vital for embryonic organ development and normal function of differentiated cells and tissues. In this study we have developed a self-assembled monolayer-based co-culture system to study tooth morphogenesis. Specifically, we designed a 2-D microenvironment present in the dental tissue by creating a well-structured, laterally organized epithelial and mesenchymal cell co-culture system by patterning the cell-attachment substrate. Chemical modifications were used to develop tunable surface patterns to facilitate epithelial-mesenchymal interactions mimicking the developing tooth. Such a design promoted interactions between monolayer’s of the 2 cell types and provided signaling cues that resulted in cellular differentiation and mineralized matrix formation. Gene expression analysis showed that these co-cultures mimicked in-vivo conditions than monolayer cultures of a single cell type.  相似文献   
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7.
Physiologically relevant in vitro models are needed to study disease progression and to develop and screen potential therapeutic interventions for disease. Heart valve disease, in particular, has no early intervention or non-invasive treatment because there is a lack of understanding the cellular mechanisms which lead to disease. Here, we establish a novel, customizable synthetic hydrogel platform that can be used to study cell–cell interactions and the factors which contribute to valve disease. Spatially localized cell adhesive ligands bound in the scaffold promote cell growth and organization of valve interstitial cells and valve endothelial cells in 3D co-culture. Both cell types maintained phenotypes, homeostatic functions, and produced zonally localized extracellular matrix. This model extends the capabilities of in vitro research by providing a platform to perform direct contact co-culture with cells in their physiologically relevant spatial arrangement.  相似文献   
8.
Despite the availability of toxicity studies on cellular exposure to gold nanoparticles (AuNPs), there is scarcity of information with regard to the bystander effects induced by AuNPs on neighboring cells not exposed to the NPs. In this study, we showed that exposure of small airway epithelial cells (SAECs) to AuNPs induced changes in protein expression associated with functional effects in neighboring MRC5 lung fibroblasts in a co-culture system. Uptake of 20 nm size AuNPs by SAECs was first verified by focused ion beam scanning electron microscopy. Subsequently, pretreated SAECs were co-cultured with unexposed MRC5 lung fibroblasts, which then underwent proteome profiling using a quantitative proteomic approach. Stable-isotope labeling by amino acids in cell culture (SILAC)–based mass spectrometry identified 109 proteins (which included 47 up-regulated and 62 down-regulated proteins) that were differentially expressed in the lung fibroblasts co-cultured with AuNP pretreated SAECs. There was altered expression of proteins such as Paxillin, breast cancer anti-estrogen resistance 1 and Caveolin-1, which are known to be involved in the cell adhesion process. Morphological studies revealed that there was a concomitant increase in cell adhesion and altered F-actin stress fiber arrangement involving vinculin in the lung fibroblasts. It is likely that phenotypic changes observed in the underlying lung fibroblasts were mediated by AuNP-induced downstream signals in the pretreated SAECs and cell–cell cross talk.  相似文献   
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10.
Photocatalytic-activation of anodized TiO2-surfaces has been demonstrated to yield antibacterial and tissue integrating effects, but effects on simultaneous growth of tissue cells and bacteria in co-culture have never been studied. Moreover, it is unknown how human-bone-marrow-mesenchymal-stem (hBMMS) cells, laying the groundwork for integration of titanium implants in bone, respond to photocatalytic activation of anodized TiO2-surfaces. Photocatalytically-activated, anodized titanium and titanium-alloy surfaces achieved 99.99% killing of adhering Staphylococcus epidermidis and Staphylococcus aureus, an effect that lasted for 30 days of storage in air. Surface coverage by osteoblasts was not affected by photocatalytic activation of anodized TiO2-surfaces. Co-cultures of osteoblasts with contaminating S. epidermidis however, enhanced surface coverage on photocatalytically-activated, anodized titanium-alloy surfaces. hBMMS cells grew less on photocatalytically-activated, anodized titanium surfaces, while not at all on photocatalytically-activated, anodized titanium-alloy surfaces and did not survive the presence of contaminating staphylococci. This reduced surface coverage by hBMMS cells disappeared when photocatalytically-activated, anodized titanium-alloy surfaces were exposed to buffer for 60 min, both in absence or presence of contaminating S. aureus. Consequently, it is concluded that photocatalytically-activated, anodized titanium and titanium-alloy surfaces will effectively kill peri-operatively introduced staphylococci contaminating an implant surface and constitute an effective means for antibiotic prophylaxis in cementless fixation of orthopaedic hardware.  相似文献   
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