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Extending the in vivo Half-Life of Adalimumab Fab via Sortase A-Mediated Conjugation of Adalimumab Fab with Modified Fatty Acids 通过排序酶a介导的阿达木单抗Fab与修饰脂肪酸的偶联,延长阿达木单抗Fab的体内半衰期
Pub Date : 2020-12-01 DOI: 10.1055/s-0041-1728817
Qingbin Zhang, Sida Ruan, Yong Wu, Jinhua Zhang, Jianguang Lu, Jun Feng
Abstract Adalimumab, a full-length monoclonal antibody, is widely used as an anti-tumor necrosis factor-α (anti-TNF-α) agent. In this article, we aimed to prolong the in vivo half-life of adalimumab antigen-binding fragment (Fab) through Sortase A (SrtA)-mediated conjugation of its Fab with fatty acid (FA). In our study, adalimumab Fab analog was prepared by adding an SrtA recognition sequence (LPETGG) and His6 tag to the heavy chain C-terminal of the Fab via (G4S)3 linker. Four FA motifs with different linkers were designed and synthesized by solid-phase methodology, then conjugated with the Fab analog using SrtA to produce Fab bioconjugates. The successful generation of four Fab bioconjugates (Fab–FA1, Fab–FA2, Fab–FA3, and Fab–FA4) was confirmed by SDS-PAGE (sodium dodecyl sulfate polyacrylamide gel electrophoresis) and mass spectrometry. Then, the bioactivities and half-life of these Fab bioconjugates were examined using TNF-α-/human serum albumin (HSA)-binding enzyme-linked immunosorbent assay, cytotoxicity assay, and pharmacokinetic study, respectively. All Fab bioconjugates exhibited similar TNF-α-neutralizing activities when compared with the Fab analog, even in the presence of albumin, indicating that there were no apparent influences on the functional site of Fab after FA modification. However, different degrees of affinity for HSA were observed among these Fab–FA bioconjugates, with Fab–FA3 exhibiting the maximal affinity. An in vivo study in mice further revealed remarkably improved pharmacokinetics of Fab– FA3 with a 15.2-fold longer plasma half-life (19.86 hours) compared with that of the Fab analog (1.31 hours). In summary, we have developed a novel long-acting adalimumab Fab bioconjugate, Fab–FA3, with more sustained in vivo activity, which can be used for drug development targeting TNF-α-mediated inflammatory diseases.
阿达木单抗是一种全长单克隆抗体,被广泛用作抗肿瘤坏死因子-α (anti-TNF-α)的药物。在本文中,我们旨在通过Sortase A (SrtA)介导的Fab与脂肪酸(FA)偶联来延长阿达木单抗抗原结合片段(Fab)的体内半衰期。在我们的研究中,阿达木单抗Fab类似物是通过(G4S)3连接体在Fab的重链c端添加SrtA识别序列(LPETGG)和His6标签制备的。采用固相法设计和合成了4个具有不同连接方式的FA基序,然后利用SrtA与Fab类似物偶联制备Fab生物偶联物。通过SDS-PAGE(十二烷基硫酸钠聚丙烯酰胺凝胶电泳)和质谱分析证实了四种Fab生物偶联物(Fab - fa1、Fab - fa2、Fab - fa3和Fab - fa4)的成功生成。然后,分别采用TNF-α-/人血清白蛋白(HSA)结合酶联免疫吸附试验、细胞毒性试验和药代动力学研究检测这些Fab生物偶联物的生物活性和半衰期。与Fab类似物相比,即使存在白蛋白,所有Fab生物偶联物也表现出相似的TNF-α-中和活性,这表明FA修饰后对Fab的功能位点没有明显影响。然而,这些Fab-FA生物偶联物对HSA的亲和力不同,以Fab-FA3表现出最大的亲和力。一项小鼠体内研究进一步表明,Fab - FA3显著改善了药代动力学,其血浆半衰期(19.86小时)比Fab类似物(1.31小时)长15.2倍。综上所述,我们开发了一种新的长效阿达木单抗Fab生物偶联物Fab - fa3,具有更持久的体内活性,可用于针对TNF-α-介导的炎症性疾病的药物开发。
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引用次数: 0
Improvement of Nemadectin Production by Overexpressing the Regulatory Gene nemR and Nemadectin Biosynthetic Gene Cluster in Streptomyces Cyaneogriseus 过表达调控基因nemR和Nemadectin生物合成基因簇对蓝灰链霉菌Nemadectin产量的影响
Pub Date : 2020-12-01 DOI: 10.1055/s-0040-1722746
Yuanjie Wu, Songbai Yang, Zhenghong Zhang, Shaoxin Chen
Abstract Nemadectin, a 16-member macrocyclic lactone antiparasitic antibiotic, is produced by Streptomyces cyaneogriseus subspecies noncyanogenus. Moxidectin, a C-23 oximate derivative of nemadectin, is widely used as a pesticide due to its broad-spectrum, highly efficient, and safe anthelmintic activity. NemR, a LAL family regulator, is encoded by nemR and is involved in nemadectin biosynthesis in S. cyaneogriseus. In this report, gene disruption and complementation experiments showed that nemR plays a positive role in the biosynthesis of nemadectin. The transcription level of nemadectin biosynthetic genes in the nemR knockout strain was significantly decreased compared with those in the wild-type strain MOX-101. However, overexpression of nemR under the control of native or strong constitutive promoters resulted in the opposite, increasing the production of nemadectin by 56.5 or 73.5%, respectively, when compared with MOX-101. In addition, the gene cluster of nemadectin biosynthesis was further cloned and overexpressed using a CRISPR method, which significantly increase nemadectin yield by 108.6% (509 mg/L) when compared with MOX-101.
Nemadectin是由链霉菌(Streptomyces cyaneogriseus) noncyanogenus亚种产生的16元大环内酯类抗寄生虫抗生素。莫西菌素是奈马菌素的C-23肟酸衍生物,具有广谱、高效、安全的驱虫活性,被广泛用作农药。NemR是LAL家族调控因子,由NemR编码,参与S. cyaneogriseus nemadectin的生物合成。在这篇报道中,基因破坏和互补实验表明nemR在nemadectin的生物合成中起着积极的作用。与野生型菌株MOX-101相比,nemR敲除菌株中nemadectin生物合成基因的转录水平显著降低。然而,在天然启动子或强组成启动子的控制下过表达nemR,结果正好相反,与MOX-101相比,nemadectin的产量分别增加了56.5%和73.5%。此外,利用CRISPR方法克隆并过表达了nemadectin生物合成基因簇,与MOX-101相比,nemadectin产量显著提高108.6% (509 mg/L)。
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引用次数: 1
Continuous-Flow Processes for the Production of Floxacin Intermediates: Efficient C–C Bond Formation through a Rapid and Strong Activation of Carboxylic Acids 生产氟沙星中间体的连续流工艺:通过羧酸的快速和强活化有效地形成C-C键
Pub Date : 2020-09-01 DOI: 10.1055/s-0040-1722215
Shaozheng Guo, Zhiqun Yu, W. Su
Abstract The development of highly efficient C–C bond formation methods for the synthesis of ethyl 2-(2,4-dichloro-5-fluorobenzoyl)-3-(dimethylamino)acrylate 1 in continuous flow processes has been described, which is based on the concept of rapid and efficient activation of carboxylic acid. 2,4-Dichloro-5-fluorobenzoic acid is rapidly converted into highly reactive 2,4-dichloro-5-fluorobenzoyl chloride by treating with inexpensive and less-toxic solid bis(trichloromethyl)carbonate. And then it rapidly reacts with ethyl 3-(dimethylamino)acrylate to afford the desired 1. This process can be performed under mild conditions. Compared with the traditional tank reactor process, less raw material consumption, higher product yield, less reaction time, higher operation safety ensured by more the environmentally friendly procedure, and process continuity are achieved in the continuous-flow system.
摘要基于羧酸快速高效活化的概念,研究了连续流法合成2-(2,4-二氯-5-氟苯甲酰基)-3-(二甲氨基)丙烯酸酯1的高效C-C成键方法。2,4-二氯-5-氟苯甲酸通过廉价和毒性较低的固体二(三氯甲基)碳酸处理,可迅速转化为高活性的2,4-二氯-5-氟苯甲酰氯。然后与3-(二甲氨基)丙烯酸乙酯迅速反应生成所需的1。这个过程可以在温和的条件下进行。与传统的罐式反应器工艺相比,在连续流系统中,原料消耗更少,产品收率更高,反应时间更短,操作安全性更高,工艺更环保,实现了工艺的连续性。
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引用次数: 0
Design, Synthesis, and Biological Evaluation of Dual c-Met/HDAC Inhibitors Bearing 2-Aminopyrimidine Scaffold 2-氨基嘧啶支架双c-Met/HDAC抑制剂的设计、合成和生物学评价
Pub Date : 2020-09-01 DOI: 10.1055/s-0040-1722543
Qingwei Zhang, Guili Xu, Yafeng Bao, Minru Jiao, Jian-qi Li
Abstract A series of c-Met/histone deacetylase (HDAC) bifunctional inhibitors was designed and synthesized by merging pharmacophores of c-Met and HDAC inhibitors. Among them, the most potent compound, 2o, inhibited c-Met kinase and HDACs, with IC50 values of 9.0 and 31.6 nM, respectively, and showed efficient antiproliferative activities against both A549 and HCT-116 cancer cell lines with greater potency than an equimolar mixture of the respective inhibitors of the two enzymes: crizotinib and vorinostat (SAHA). Our study provided an efficient strategy for the discovery of multitargeted antitumor drugs.
摘要将c-Met/组蛋白去乙酰化酶(HDAC)抑制剂的药效团合并,设计合成了一系列c-Met/组蛋白去乙酰化酶(HDAC)双功能抑制剂。其中,最有效的化合物20抑制c-Met激酶和hdac, IC50值分别为9.0和31.6 nM,对A549和HCT-116癌细胞均显示出有效的抗增殖活性,其效力高于两种酶抑制剂克唑替尼和伏立诺他(SAHA)的等摩尔混合物。我们的研究为发现多靶点抗肿瘤药物提供了一种有效的策略。
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引用次数: 0
Another Critical Look at Three-Phase Catalysis 三相催化的另一个关键观点
Pub Date : 2020-09-01 DOI: 10.1055/s-0040-1722219
X. Ni
Abstract Three-phase catalysis, for example, hydrogenation, is a special branch of chemical reactions involving a hydrogen reactant (gas) and a solvent (liquid) in the presence of a metal porous catalyst (solid) to produce a liquid product. Currently, many reactors are being used for three-phase catalysis from packed bed to slurry vessel; the uniqueness for this type of reaction in countless processes is the requirement of transferring gas into liquid, as yet there is not a unified system of quantifying and comparing reactor performances. This article reviews current methodologies in carrying out such heterogeneous catalysis in different reactors and focuses on how to enhance reactor performance from gas transfer perspectives. This article also suggests that the mass transfer rate over energy dissipation may represent a fairer method for comparison of reactor performance accounting for different types/designs of reactors and catalyst structures as well as operating conditions.
三相催化,如加氢,是化学反应的一个特殊分支,涉及氢反应物(气体)和溶剂(液体)在金属多孔催化剂(固体)的存在下产生液体产物。目前,许多反应器用于从填料床到料浆容器的三相催化;这类反应在无数过程中的独特之处在于需要将气体转化为液体,目前还没有一个统一的系统来量化和比较反应器的性能。本文综述了目前在不同反应器中进行这种多相催化的方法,并着重从气体传递的角度介绍了如何提高反应器的性能。本文还提出,考虑到不同类型/设计的反应器和催化剂结构以及操作条件,传质率除以能量耗散可能是比较反应器性能的一种更公平的方法。
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引用次数: 0
Ameliorative and Safety Characteristics of Argemone mexicana in Indomethacin-Induced Peptic Ulcer 银银酮治疗吲哚美辛所致消化性溃疡的疗效及安全性研究
Pub Date : 2020-09-01 DOI: 10.1055/s-0040-1722216
O. Idowu, R. Arise
Abstract Argemone mexicana (A. mexicana) is a plant traditionally used in Nigeria and some African countries to treat peptic ulcer disease. In this study, the ameliorative effect of ethanolic leaf extract of A. mexicana in indomethacin-induced peptic ulcer and its safety were investigated. Phytochemical screening was performed using standard procedures. Ulcer was induced in rats by single oral administration dose of 25 mg/kg body weight (b.w.) indomethacin followed by treatment with 100, 200, and 400 mg/kg b.w. ethanolic leaf extract of A. mexicana. Ulcer-related indices such as gastric pH, acidity, pepsin, and Na+/K+-ATPase activities, glycoprotein, and mucus contents were determined. The status of antioxidant enzymes (superoxide dismutase, catalase, glutathione peroxidase, reductase, and transferase) in the stomach and duodenum of the rats was also evaluated. Safety of the extract in the liver and kidney was investigated by chromosomal aberration. The results showed that alkaloids, flavonoids, phenolics, and saponins present in the extract as phytochemical constituents. The extract at 200 mg/kg b.w. significantly (p < 0.05) attenuated the gastric pH, volume, and acidity of the stomach. It also significantly (p < 0.05) enhanced the glycoprotein and mucus contents in the mucosal membrane of rats. The status of antioxidant enzymes (superoxide dismutase, catalase, glutathione peroxidase, reductase, and transferase) in both tissues was also significantly improved. Study on safety evaluation revealed that the extract is relatively safe at the most active dose investigated. The study concluded that A. mexicana could serve as an alternative therapy for the development of a safer antiulcer drug.
摘要墨西哥Argemone mexicana (a . mexicana)是尼日利亚和一些非洲国家传统上用于治疗消化性溃疡疾病的植物。本研究考察了墨西哥金针叶乙醇提取物对吲哚美辛所致消化性溃疡的改善作用及其安全性。采用标准程序进行植物化学筛选。用吲哚美辛25 mg/kg体重(b.w.)单次口服,然后分别用100、200、400 mg/kg体重(b.w.)墨西哥金针叶乙醇提取物诱导大鼠溃疡。测定溃疡相关指标,如胃pH、酸度、胃蛋白酶、Na+/K+- atp酶活性、糖蛋白和粘液含量。测定大鼠胃和十二指肠中抗氧化酶(超氧化物歧化酶、过氧化氢酶、谷胱甘肽过氧化物酶、还原酶和转移酶)的状态。采用染色体畸变法研究了该提取物在肝脏和肾脏中的安全性。结果表明,提取物中含有生物碱、黄酮类化合物、酚类物质和皂苷等植物化学成分。200 mg/kg b.w.提取物显著(p < 0.05)降低了胃pH值、胃容量和胃酸度。显著(p < 0.05)提高了大鼠粘膜糖蛋白和黏液含量。抗氧化酶(超氧化物歧化酶、过氧化氢酶、谷胱甘肽过氧化物酶、还原酶和转移酶)在两种组织中的状态也显著改善。安全性评价研究表明,在研究的最有效剂量下,提取物是相对安全的。该研究的结论是,墨西哥芽孢杆菌可以作为一种替代疗法,用于开发更安全的抗溃疡药物。
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引用次数: 1
Dual Inhibitors Targeting DNA and Histone Deacetylases 靶向DNA和组蛋白去乙酰化酶的双重抑制剂
Pub Date : 2020-06-01 DOI: 10.1055/s-0040-1713873
Chen Chen, Xinying Yang, Xuben Hou, H. Fang
Abstract Histone deacetylases (HDACs) regulate the acetylation status of histones and structural status of chromatin. The chromatin structure becomes relaxed after inhibition of HDAC, leading to DNA exposed to DNA disrupting agents, and eventually causing DNA dysfunction. Recently, more and more dual inhibitors targeting DNA and HDACs have been reported to be applied to cancer treatment. In this review, we describe the current status of dual inhibitors targeting DNA and HDACs, summarize their pharmacological characters, and predict their further trend in the field.
组蛋白去乙酰化酶(hdac)调节组蛋白的乙酰化状态和染色质的结构状态。抑制HDAC后,染色质结构变得松弛,导致DNA暴露于DNA干扰剂中,最终导致DNA功能障碍。近年来,越来越多的针对DNA和hdac的双重抑制剂被报道用于癌症治疗。本文综述了DNA和hdac双重抑制剂的研究现状,总结了它们的药理特性,并对它们在该领域的发展趋势进行了展望。
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引用次数: 0
Natural Occurrence, Biological Functions, and Analysis of D-Amino Acids d -氨基酸的自然存在、生物学功能和分析
Pub Date : 2020-06-01 DOI: 10.1055/s-0040-1713820
Shuang‐Xi Gu, Haifeng Wang, Yuan-Yuan Zhu, Fener Chen
Abstract This review covers the recent development on the natural occurrence, functional elucidations, and analysis of amino acids of the D (dextro) configuration. In the pharmaceutical field, amino acids are not only used directly as clinical drugs and nutriments, but also widely applied as starting materials, catalysts, or chiral ligands for the synthesis of active pharmaceutical ingredients. Earler belief hold that only L-amino acids exist in nature and D-amino acids were artificial products. However, increasing evidence indicates that D-amino acids are naturally occurring in living organisms including human beings, plants, and microorganisms, playing important roles in biological processes. While D-amino acids have similar physical and chemical characteristics with their respective L-enantiomers in an achiral measurement, the biological functions of D-amino acids are remarkably different from those of L-ones. With the rapid development of chiral analytical techniques for D-amino acids, studies on the existence, formation mechanisms, biological functions as well as relevant physiology and pathology of D-amino acids have achieved great progress; however, they are far from being sufficiently explored.
摘要本文综述了近年来在D(右旋)结构氨基酸的天然存在、功能解释和分析方面的研究进展。在医药领域,氨基酸不仅直接用作临床药物和营养物质,还广泛用作药物活性成分合成的起始原料、催化剂或手性配体。早期的观点认为自然界中只有l -氨基酸存在,d -氨基酸是人工产物。然而,越来越多的证据表明,d -氨基酸自然存在于包括人类、植物和微生物在内的生物体中,在生物过程中起着重要作用。在非手性测量中,d -氨基酸与其l -对映体具有相似的物理和化学特性,但其生物学功能与l -对映体有显著差异。随着d -氨基酸手性分析技术的迅速发展,对d -氨基酸的存在、形成机制、生物学功能以及相关生理病理的研究取得了很大进展;然而,它们还远远没有得到充分的探索。
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引用次数: 2
IL-1Ra Protects Hepatocytes from CCl4-Induced Hepatocellular Apoptosis via Activating the ERK1/2 Pathway IL-1Ra通过激活ERK1/2通路保护肝细胞免受ccl4诱导的肝细胞凋亡
Pub Date : 2020-06-01 DOI: 10.1055/s-0040-1714139
Ying Zheng, Xinyi Xiao, Zhuoyi Yang, Mei-Yi Zhou, Hui Chen, S. Bai, Jian-jia Zhu, Y. Yuan
Abstract Interleukin-1 receptor antagonist is an important acute-phase protein and an immune mediator, and its expression is associated with the development of hepatitis or acute liver failure. The aim of this study was to investigate whether recombinant human interleukin-1 receptor antagonist directly targets and improves cell survival in a carbon tetrachloride-induced hepatocyte injury model in vitro. A human hepatoma cell line and a mouse hepatocyte cell line were used to establish carbon tetrachloride-induced cell injury models in vitro, and cell viability, apoptosis, and reactive oxygen species level were determined to assess the degree of hepatocellular damage. Quantitative real-time polymerase chain reaction was used to analyze the level of interleukin-1β, interleukin-6, and tumor necrosis factor-α mRNA in cells; extracellular regulated protein kinases 1/2 phosphorylation in hepatocytes was analyzed using western blotting. Recombinant human interleukin-1 receptor antagonist could directly target hepatocytes, improve cell survival, and decrease carbon tetrachloride-induced cell apoptosis in vitro. In hepatocytes, recombinant human interleukin-1 receptor antagonist remarkably downregulated expression of interleukin-1β, interleukin-6, and tumor necrosis factor-α in hepatocytes exposed to carbon tetrachloride. It also decreased accumulation of reactive oxygen species and abrogated the suppression of extracellular regulated protein kinases 1/2 phosphorylation induced by carbon tetrachloride. However, stimulation of cells with an extracellular regulated protein kinases 1/2 inhibitor blocked the recombinant human interleukin-1 receptor antagonist-induced upregulation of extracellular regulated protein kinase1/2 activation and abrogated the improvement in hepatocyte survival following carbon tetrachloride treatment. Collectively, these findings provide new insights into the hepatocyte-protective mechanism of recombinant human interleukin-1 receptor antagonist.
白细胞介素-1受体拮抗剂是一种重要的急性期蛋白和免疫介质,其表达与肝炎或急性肝衰竭的发生有关。本研究的目的是探讨重组人白细胞介素-1受体拮抗剂是否直接靶向并改善四氯化碳诱导的体外肝细胞损伤模型中的细胞存活。采用人肝癌细胞系和小鼠肝细胞细胞系建立体外四氯化碳诱导的细胞损伤模型,测定细胞活力、凋亡和活性氧水平,评估肝细胞损伤程度。采用实时定量聚合酶链反应分析细胞中白细胞介素-1β、白细胞介素-6、肿瘤坏死因子-α mRNA水平;肝细胞细胞外调节蛋白激酶1/2磷酸化用western blotting分析。重组人白细胞介素-1受体拮抗剂能直接靶向肝细胞,提高肝细胞存活率,减少四氯化碳诱导的肝细胞凋亡。在肝细胞中,重组人白细胞介素-1受体拮抗剂显著下调四氯化碳暴露的肝细胞中白细胞介素-1β、白细胞介素-6和肿瘤坏死因子-α的表达。它还减少了活性氧的积累,消除了四氯化碳诱导的细胞外调节蛋白激酶1/2磷酸化的抑制。然而,用细胞外调节蛋白激酶1/2抑制剂刺激细胞阻断了重组人白细胞介素-1受体拮抗剂诱导的细胞外调节蛋白激酶1/2激活的上调,并取消了四氯化碳处理后肝细胞存活率的改善。总的来说,这些发现为重组人白细胞介素-1受体拮抗剂的肝细胞保护机制提供了新的见解。
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引用次数: 3
Generating a Novel Bispecific Nanobody to Enhance Antitumor Activity 一种新型双特异性纳米体增强抗肿瘤活性
Pub Date : 2020-06-01 DOI: 10.1055/s-0040-1714138
Q. Ge, Tianyuan Sun, Yan-lin Bian, Xiaodong Xiao, Jianwei Zhu
Abstract Tumor cells express high levels of human epidermal growth factor receptor 2 (HER2) and vascular endothelial growth factor receptor 2 (VEGFR2), which are closely related to their proliferation and survival. Cancer treatments that target a single signaling pathway may result in immune pathway escape or drug resistance. Based on the correlation between the HER2 and VEGFR2 signaling pathways, we speculated that targeting the two pathways simultaneously may produce a synergistic effect and avoid occurrence of drug resistance, resulting in improved efficacy. Anti-VEGFR2 nanobody 3VGR19–3 and anti-HER2 nanobody 2D3 were combined to construct a bispecific nanobody (Bi-Nb). They can recognize both HER2 and VEGFR2 (both highly expressed in HT-29 cells) to simultaneously block the two signaling pathways. We verified the affinity of the Bi-Nb to its targets using the surface plasmon resonance technology, and test its effects to inhibit tumor cell growth and promote cell apoptosis in vitro by the Cell Counting Kit-8 assay and apoptosis assay. In summary, we have successfully constructed a Bi-Nb, and verified its tumor-suppressing effects in vitro. Compared with a single monospecific nanobody, our Bi-Nb showed superior antitumor effect, which provides a new perspective for treatment of tumors with high HER2 and VEGFR2 expression.
肿瘤细胞高水平表达人表皮生长因子受体2 (HER2)和血管内皮生长因子受体2 (VEGFR2),与肿瘤细胞的增殖和存活密切相关。针对单一信号通路的癌症治疗可能导致免疫通路逃逸或耐药性。根据HER2和VEGFR2信号通路的相关性,我们推测同时靶向这两条通路可能会产生协同作用,避免耐药的发生,从而提高疗效。将抗vegfr2纳米体3VGR19-3与抗her2纳米体2D3结合构建双特异性纳米体(Bi-Nb)。它们可以同时识别HER2和VEGFR2(两者都在HT-29细胞中高度表达),从而同时阻断这两条信号通路。我们利用表面等离子体共振技术验证了Bi-Nb与靶点的亲和力,并通过细胞计数试剂盒-8和细胞凋亡实验验证了其体外抑制肿瘤细胞生长和促进细胞凋亡的作用。综上所述,我们成功构建了Bi-Nb,并在体外验证了其肿瘤抑制作用。与单一的单特异性纳米体相比,我们的Bi-Nb具有更强的抗肿瘤作用,为治疗HER2和VEGFR2高表达的肿瘤提供了新的视角。
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引用次数: 2
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Pharmaceutical Fronts
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