鸭C4BPα的克隆、表达及其与鸭疫里默氏菌的互作

为研究鸭C4结合蛋白(C4b-binding protein,C4BP)与鸭疫里默氏菌(Riemerella anatipestifer,RA)的相互作用,对鸭C4BPα进行克隆、原核表达,免疫小鼠制备多克隆抗体,并利用间接免疫荧光试验及斑点杂交试验验证C4BP与RA的相互作用。结果显示,鸭C4BPα核苷酸序列全长为1230bp,与鸡C4BPα的相似性最高(82.1%);系统进化树分析发现,鸭C4BPα与鸡C4BPα处于同一系统进化树分支上,两者遗传进化关系最近;C4BPα在大肠杆菌Escherichia coli BL21 (DE3)中能高效表达,重组蛋白以胞内可溶性形式存在;多克隆抗体效价超过1∶10000,并且可以与重组蛋白发生特异性反应;间接免疫荧光试验和斑点杂交试验结果显示RA与鸭C4BP可以发生相互作用。研究结果为进一步揭示RA的致病机制奠定了基础。     

Canopy photosynthesis modulates soil respiration in a temperate semi-arid shrubland at multiple timescales

Plant and Soil - Plant growth-promoting bacteria of the genus Bacillus are known to solubilize phosphates and enhance plant growth in many plant species. We explored the effects of the inoculation...     

Expression profiles of microRNAs in oxidized low-density lipoprotein-stimulated RAW 264.7 cells

Macrophage-derived foam cells were one of the hallmarks of atherosclerosis, and microRNAs played an important role in the formation of foam cells. In order to explore the roles of miRNA in the formation of foam cells, we investigated miRNA expression profiles in foam cells through high-throughput sequencing technology. A total of 84 miRNAs were differentially expressed between RAW 264.7 macrophages and foam cells induced by ox-LDL. Thirty miRNAs were upregulated and 54 miRNAs were downregulated. GO terms and KEGG pathways analysis revealed that the target genes of most of DE miRNAs were mainly enriched in “cell differentiation,” “endocytosis,” “MAPK signaling pathway,” and “FoxO signaling pathway.” The target genes of some DE miRNAs were enriched in “Insulin signaling pathway,” “Hippo signaling pathway,” “TNF signaling pathway,” “NF-kappa B signaling pathway,” and “cell death.” Using bioinformatics analyses and dual-luciferase reporter assays, we found that miR-28a-5p and miR-30c-1-3p directly inhibited LRAD3 and LOX-1 mRNA expression through targeting the 3’UTR of LRAD3 and LOX-1 mRNA, respectively. Our study indicates that miRNAs are extensively involved in the formation of foam cells, and provides a valuable resource for further study the role of miRNAs in atherosclerosis.     

Polycyclic aromatic hydrocarbons (PAHs) concentration levels,pattern, source identification,and human risk assessment in foliar dust from urban to rural areas in Nanjing,China

Environmental health is an essential component of quality of life in modern societies. Foliar dust contains polycyclic aromatic hydrocarbons (PAHs) that may have harmful effects on human health. The PAHs concentration of foliar dust is useful to assess environmental air pollution. Our results indicate that: (1) the highest levels of PAHs were distributed in urban areas, with a mean of 3430.23 ng·g^?1, lower mean concentrations were found in suburban (2282.12 ng·g^?1), and rural areas (1671.06 ng·g^?1). (2) Diagnostic ratios and principal component analysis were used to identify the sources of PAHs: Gasoline vehicle traffic emissions were the predominant source in urban areas, along with coal and coke combustion. In suburban areas, the main sources were petroleum combustion (especially liquid fossil fuels) and coal combustion. Coal and wood combustion were the primary source of PAHs in foliar dust in rural areas. (3) The incremental lifetime cancer risk (ILCR), estimated based on the results of this study indicate that urban residents were potentially exposed to high cancer risk via both dust ingestion and dermal contact. We conclude that urbanization has significant effects on the PAH concentrations of foliar dust, illustrating the importance of trees in improving air quality in urban areas.     

Large-scale expansion of Vγ9Vδ2 T cells with engineered K562 feeder cells in G-Rex vessels and their use as chimeric antigen receptor–modified effector cells

Vγ9Vδ2 T cells are a minor subset of lymphocytes in the peripheral blood that has been extensively investigated for their tolerability, safety and anticancer efficacy. A hindrance to the broad application of these cells for adoptive cellular immunotherapy has been attaining clinically appropriate numbers of Vγ9Vδ2 T cells. Furthermore, Vγ9Vδ2 T cells exist at low frequencies among cancer patients. We, therefore, sought to conceive an economical method that allows for a quick and robust large-scale expansion of Vγ9Vδ2 T cells. A two-step protocol was developed, in which peripheral blood mononuclear cells (PBMCs) from healthy donors or cancer patients were activated with Zometa and interleukin (IL)-2, followed by co-culturing with gamma-irradiated, CD64-, CD86- and CD137L-expressing K562 artificial antigen-presenting cells (aAPCs) in the presence of the anti-CD3 antibody OKT3. We optimized the co-culture ratio of K562 aAPCs to immune cells, and migrated this method to a G-Rex cell growth platform to derive clinically relevant cell numbers in a Good Manufacturing Practice (GMP)-compliant manner. We further include a depletion step to selectively remove αβ T lymphocytes. The method exhibited high expansion folds and a specific enrichment of Vγ9Vδ2 T cells. Expanded Vγ9Vδ2 T cells displayed an effector memory phenotype with a concomitant down-regulated expression of inhibitory immune checkpoint receptors. Finally, we ascertained the cytotoxic activity of these expanded cells by using nonmodified and chimeric antigen receptor (CAR)–engrafted Vγ9Vδ2 T cells against a panel of solid tumor cells. Overall, we report an efficient approach to generate highly functional Vγ9Vδ2 T cells in massive numbers suitable for clinical application in an allogeneic setting.     

真菌次级代谢产物rasfonin促进舒尼替尼(Sunitinib)诱导的肾癌细胞自噬和凋亡

【目的】明确真菌次级代谢产物rasfonin影响舒尼替尼(Sunitinib,ST)诱导的肾癌细胞自噬和凋亡作用机理。【方法】应用MTS(Methanethiosulfonate assay)和克隆形成实验检测rasfonin和舒尼替尼对肾癌细胞ACHN活性和增殖的影响,通过透射电子显微镜、荧光显微镜、蛋白免疫印迹、免疫荧光方法检测rasfonin和舒尼替尼处理的ACHN细胞自噬、凋亡情况和相关信号通路的变化。【结果】Rasfonin和舒尼替尼能够抑制肾癌细胞ACHN活性和细胞增殖;免疫印迹结果表明,两者均可以引起caspase依赖的凋亡。在rasfonin存在的情况下,不仅舒尼替尼所引起的凋亡和细胞活性丢失明显增加,而且其诱导的自噬流显著提高。无论是rasfonin还是舒尼替尼均明显地抑制哺乳雷帕霉素靶蛋白m TOR(Mammal target of rapamycin)磷酸化,而两者均能促进细胞外调节蛋白激酶(Extracellular regulated protein kinases,ERK)活性增加。【结论】rasfonin促进了舒尼替尼诱导的细胞自噬和凋亡,提高了舒尼替尼抑制肾癌细胞增殖的活性。