Publications by authors named "Wenfeng Xu"

47 Publications

Integrative Analysis of the Expression of SIGLEC Family Members in Lung Adenocarcinoma via Data Mining.

Front Oncol 2021 16;11:608113. Epub 2021 Mar 16.

Public Experimental Technology Center, The School of Basic Medical Science, Southwest Medical University, Luzhou, China.

Sialic acid-binding immunoglobulin-type lectin (SIGLEC) family members are involved in regulating immune-cell activation, proliferation, and apoptosis, and they play an important role in tumor development. However, their expression and correlation with immune molecules in lung adenocarcinoma (LUAD) remain unclear. We utilized Gene Expression Profiling Interactive Analysis, Kaplan-Meier analysis, the limma package in R/Bioconductor, the University of California Santa Cruz Cancer Genome Browser, cBioPortal, STRING, Cytoscape, DAVID, and the Tumor Immune Estimation Resource for gene and protein profiling and analyses. The results showed that SIGLEC10 and SIGLEC15 levels were upregulated in LUAD, whereas SIGLEC1, CD22 (SIGLEC2), CD33, myelin-associated glycoprotein (SIGLEC4), SIGLEC5, SIGLEC6, SIGLEC7, SIGLEC8, SIGLEC11, and SIGLEC14 levels were significantly downregulated, with their low expression associated with poor overall survival. Moreover, we observed high SIGLEC-mutation rates (22%) in LUAD patients, with SIGLEC functions determined as primarily involved in regulating the immune response, signal transduction, inflammatory response, and cell adhesion. Furthermore, we found that SIGLEC expression was significantly correlated with immune-cell infiltration, especially macrophages, neutrophils, and dendritic cells, and highly associated with immune molecules such as CD80, CD86, CD28, B-cell-activating factor, programmed cell death 1 ligand 2, and colony stimulating factor 1 receptor. These results provide insight into the potential molecular mechanism associated with SIGLEC-related development of LUAD, as well as clues for screening biomarkers and therapeutic targets.
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http://dx.doi.org/10.3389/fonc.2021.608113DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8008066PMC
March 2021

Occurrence of antibiotics in the Xiaoqing River basin and antibiotic source contribution-a case study of Jinan city, China.

Environ Sci Pollut Res Int 2021 Jan 16. Epub 2021 Jan 16.

Institute of Environment and Ecology, Shandong Normal University, Jinan, 250358, China.

Twenty antibiotics were investigated to evaluate the degree of antibiotic pollution, the temporal and spatial antibiotic distribution and the ecological risks in the Xiaoqing River basin (main stream). The total antibiotic concentrations in surface water and sediment were 0.99 to 832.4 ng L and 9.71 to 7841.61 ng g, respectively, and that ofloxacin was the dominant antibiotic. However, ofloxacin, erythromycin, clarithromycin and sulfamethoxazole posed high risks to algae, among which clarithromycin presented the highest risk quotients (23.8). In addition, there were spatial and temporal differences in the antibiotic concentration distribution. Temporally, the following trend was detected: dry season > normal season > wet season; spatially, the following trend was detected: Jinan > Dongying > Binzhou > Zibo > Weifang. Meanwhile, we used the PCA-MLR model to quantify the contribution rate of the four sewage treatment plants A, B, C and D. Factor 1 (co-sources A, B, C, D) contributed 64.1% of the total antibiotic concentration in the Xiaoqing River. According to the estimated flux into the sea, approximately 972.31 kg of antibiotics were discharged into Bohai Bay in 2017, posing a potential threat to the marine ecosystem. As a comprehensive river channel used for flood control, waterlogging, irrigation and shipping, its water quality safety is of great significance to the surrounding residents and ecological safety. Therefore, further investigations of antibiotic pollution and source contribution are necessary.
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http://dx.doi.org/10.1007/s11356-020-12202-zDOI Listing
January 2021

[House dust mite extract activates EphA2-STAT3/p38 MAPK signaling pathway in airway epithelial cells to mediate airway inflammation].

Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi 2021 Jan;37(1):31-38

Department of Immunology, School of Basic Medical Sciences, Southwest Medical University, Luzhou 646000, China. *Corresponding author, E-mail:

Objective To investigate the effect of ephrin type-A receptor 2 (EphA2) on the expression of inflammatory cytokines in airway epithelial cells induced by house dust mite extract (HDM) and the underlying mechanism. Methods The cell model of EphA2 knockdown was established by transfection of EphA2 siRNA into airway cell line 16HBE cells. After the 16HBE cells were stimulated with HDM, the mRNA levels of EphA2, interleukin 6 (IL-6) and IL-8 were determined by real-time quantitative PCR (qPCR), and the protein levels of IL-6, IL-8, IL-17A, IL-17F and tumor necrosis factor-α (TNF-α) were measured by cytometric bead array (CBA). Western blotting was used to analyze the protein expression of EphA2, phosphorylated EphA2 (p-EphA2), signal transducer and activator of transcription (STAT3), phosphorylated STAT3 (p-STAT3), p38 mitogen-activated protein kinases (p38 MAPK), phosphorylated p38 MAPK (p-p38 MAPK), nuclear factor κ-B p65 (NF-κB p65) and phosphorylated NF-κB p65 (p-NF-κB p65). Then, in the 16HEB cells stimulated by STAT3 inhibitor Stattic or p38 MAPK inhibitor SB203580 in combination with HDM, the mRNA and protein expression levels of IL-6 and IL-8 were detected by qPCR and CBA. Results Knockdown of EphA2 significantly inhibited the expression of IL-6 and IL-8 in HDM-induced 16HBE, and reduced the total protein and phosphorylated levels of STAT3 and p38 MAPK, but had no significant effect on the total protein and phosphorylated levels of NF-κB p65. After stattic inhibited the expression and activation of STAT3, the mRNA and protein levels of IL-6 and IL-8 significantly decreased in HDM-induced 16HBE cells. Interestingly, while SB203580 inhibited the activation of p38 MAPK signaling pathway, it only inhibited the mRNA levels of IL-6 and IL-8 in HDM-induced 16HBE cells, but had no effect on their protein levels. Conclusion HDM can induce the expression of IL-6 and IL-8 in 16HBE cells to participate in airway inflammation by activating the EphA2-STAT3/p38 MAPK pathway.
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January 2021

Enrichment of circulating tumor-derived extracellular vesicles from human plasma.

J Immunol Methods 2021 Mar 24;490:112936. Epub 2020 Nov 24.

Departments of BioAnalytical Sciences, South San Francisco, CA, United States of America. Electronic address:

Extracellular vesicles (EVs) are gaining considerable traction within the liquid biopsy arena, as carriers of information from cells in distant sites that may not be accessible for biopsy. Therefore, there is a need to develop methods to enrich for specific EV subtypes, based on their cells of origin. Here we describe the development of an automated method to enrich tumor-derived EVs from plasma using the CellSearch technology compared to Total EVs isolated using differential ultracentrifugation (DUC). We use a modified CellSearch protocol to enrich EpCAM+ EVs from the plasma of patients with non-small cell lung carcinoma (NSCLC) and triple negative breast cancer (TNBC). As a test case, we examined PD-L1, an immune checkpoint ligand known to be expressed in some tumor tissues, to demonstrate enrichment for EpCAM+ EVs. For this purpose, we developed two custom immunoassays utilizing the Simoa HD-1 analyzer (Quanterix) to detect PD-L1 in EVs and interrogate specific EV populations from human plasma. PD-L1 was present in Total EVs from the plasma of healthy individuals and cancer patients, since it is also expressed on several immune cells. However, EpCAM+ EVs were only detectable from the plasma of cancer patients, suggesting these are tumor-derived EVs. As low as 250 μL of plasma could be used to reliably detect PD-L1 from patient-derived EpCAM+ EVs. In summary, this report demonstrates the development of a robust tumor-derived EV enrichment method from human blood. Furthermore, this proof-of-concept study is extendable to other known cancer-specific proteins expressed on EVs exuded from tumors.
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http://dx.doi.org/10.1016/j.jim.2020.112936DOI Listing
March 2021

Arsenic Accumulation of Realgar Altered by Disruption of Gut Microbiota in Mice.

Evid Based Complement Alternat Med 2020 18;2020:8380473. Epub 2020 Aug 18.

Department of Pharmacy, Beijing Hospital, National Center of Gerontology, Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, Beijing 100730, China.

Objective: To investigate the influence of gut microbiota on arsenic accumulation of realgar in mice.

Methods: Mice were treated with antibiotics to form a mouse model of gut microbial disruption. Antibiotic-treated and normally raised mice were given 15 mg/kg, 150 mg/kg, and 750 mg/kg realgar by gavage and 0.2 mg/kg and 1 mg/kg arsenic solution by subcutaneous injection for 7 days. The concentration of arsenic in mice whole blood was determined by inductively coupled plasma mass spectrometry (ICP-MS). Arsenic accumulation in antibiotic-treated mice and normally raised mice was compared.

Results: After exposure to low dose (15 mg/kg) and middle dose (150 mg/kg) of realgar, significantly, more arsenic was accumulated in the whole blood of antibiotic-treated mice compared to normally raised counterparts, which indicated that the disruption of gut microbiota could lead to higher arsenic load of realgar in mice. The homeostasis of gut microbiota was supposed to be disrupted by high dose (750 mg/kg) of realgar because after exposure to high dose of realgar, there was no significant difference in arsenic accumulation between antibiotic-treated and normally raised mice. Furthermore, arsenic solution was administered by subcutaneous injection to mice to investigate the influence of gut microbial differences on arsenic accumulation in addition to the absorption process, and there was no significant difference in arsenic accumulation between mice with these two different statuses of gut microbiota.

Conclusions: Gut microbiota disruption could increase arsenic accumulation of realgar in mice.
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http://dx.doi.org/10.1155/2020/8380473DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7450324PMC
August 2020

High-sensitivity Detection of Cysteine and Glutathione Using Au Nanoclusters Based on Aggregation-induced Emission.

J Fluoresc 2020 Dec 8;30(6):1491-1498. Epub 2020 Sep 8.

Chongqing Engineering Laboratory of Nano/Micro Biomedical Detection, Chongqing Key Laboratory of Nano/Micro Composite Materials and Devices, Chongqing University of Science and Technology, No. 12 East road, University town, 401331, Chongqing, People's Republic of China.

Gold nanoclusters (AuNCs) stabilized by glutathione (GSH) have been synthesized using a simple one-pot method, which were used as a fluorescence-enhanced probe for the detection of cysteine (Cys) and GSH. The detection is based on the finding that the weak yellow fluorescence of the AuNCs, with excitation/emission maxima of 430/600 nm, can be enhanced by Cys and GSH via NCs aggregation. This method is selective for Cys and GSH. According to the fluorescence enhancement, the detection ranges of AuNCs for Cys and GSH are 2.49 µM ~ 0.80 mM and 1.99 µM ~ 0.44 mM, with the detection limit of 0.42 µM and 0.27 µM, respectively. In addition, the probe has good anti-interference performance over other common biomolecules. Importantly, the probe is successfully used for the determination of Cys in human serum samples, displaying the potential application of the probe in the detection of biological sulfhydryl molecules in actual samples.
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http://dx.doi.org/10.1007/s10895-020-02618-8DOI Listing
December 2020

Inhibition of Aurora Kinase A by Alisertib Reduces Cell Proliferation and Induces Apoptosis and Autophagy in HuH-6 Human Hepatoblastoma Cells.

Onco Targets Ther 2020 8;13:3953-3963. Epub 2020 May 8.

Department of Pathology, Molecular Medicine and Cancer Research Center, Chongqing Medical University, Chongqing 400016, People's Republic of China.

Purpose: Aurora kinase A (AURKA), which belongs to the serine/threonine protein kinase family, has been identified as a key driver of the genesis and progression of diverse tumors. The aim of this study was to determine the clinical significance of AURKA in patients with hepatoblastoma (HB) and the effect of inhibiting AURKA in the HB cell line HuH-6.

Methods: The expression of AURKA in HB tissue and adjacent normal liver tissue was detected by immunohistochemistry. Then, statistical analysis was performed to evaluate the association between AURKA expression and the clinicopathological characteristics of HB. The effect of AURKA knockdown on cell viability was assessed by CCK-8 assay. EdU and CCK-8 assays, Western blotting, flow cytometry, and transmission electron microscopy (TEM) were used to examine the effect of alisertib (ALS), a selective AURKA small-molecule inhibitor, on the cell cycle, proliferation, apoptosis, and autophagy in HuH-6 human hepatoblastoma cells.

Results: The expression of AURKA was significantly higher in HB tissue than in adjacent normal tissue. Furthermore, high AURKA expression was associated with advanced Children's Oncology Group (COG) stage and tumor metastasis of HB. In vitro, AURKA knockdown significantly reduced the viability of HuH-6 cells, while ALS treatment significantly suppressed HuH-6 cell proliferation and induced G1-phase cell cycle arrest by reducing cyclin-D1 expression. Moreover, ALS promoted apoptosis and autophagy by decreasing the activity of p38 MAPK in HuH-6 cells.

Conclusion: High expression of AURKA is a potential predictor of poor prognosis in HB patients. AURKA knockdown reduced the viability of HuH-6 cells, and ALS treatment inhibited cell proliferation and induced apoptosis and autophagy via the p38 MAPK signaling pathway. Our results suggest that AURKA may be a novel therapeutic target and ALS a potential therapeutic drug for the treatment of HB.
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http://dx.doi.org/10.2147/OTT.S228656DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7217307PMC
May 2020

Affinity improvement of the fully human anti‑TSLP recombinant antibody.

Mol Med Rep 2020 Feb 12;21(2):759-767. Epub 2019 Dec 12.

State Key Laboratory of Quality Research in Chinese Medicines, Macau Institute for Applied Research in Medicine and Health, Macau University of Science and Technology, Taipa, Macau SAR 000853, P.R. China.

Thymic stromal lymphopoietin (TSLP) is a potentially important target for the treatment of asthma and malignancies. However, a fully human antibody reactive with TSLP is currently unavailable for clinical use. In a previous study, a human anti‑TSLP‑single‑chain antibody variable fragment (anti‑TSLP‑scFv) 84 was selected by phage display from a constructed human scFv library. In the present study, a computer simulation method was developed using Discovery Studio 4.5 software, to increase the affinity of anti‑TSLP‑scFv‑84. Specific primers were designed and mutated DNA sequences of anti‑TSLP‑scFvs were obtained by overlap extension PCR. The mutant scFvs were expressed in pLZ16 and affinity‑enhanced anti‑TSLP‑scFv‑M4 was screened using ELISA. However, in general the scFvs have low stability and short half‑lives in vivo. Therefore, scFv‑84 and scFv‑M4 were inserted into eukaryotic expression vectors (pcDNA3.1‑sp‑Fc and PMH3EN‑sp‑Fc) and then transfected into 293F cells to express anti‑TSLP‑scFv‑Fc. ELISA and western blotting results indicated the size of the anti‑TSLP‑scFv‑Fc to be ~50 kDa. Binding of anti‑TSLP‑scFv‑Fc‑M4 to TSLP was enhanced compared with the pre‑mutated scFv‑Fc‑84. The affinity of the mutated recombinant antibody was determined using the BIAcore technique and found to be ~10‑fold greater than the pre‑mutated antibody.
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http://dx.doi.org/10.3892/mmr.2019.10880DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6947841PMC
February 2020

Arsenic Bioaccessibility of Realgar Influenced by the Other Traditional Chinese Medicines in Niuhuang Jiedu Tablet and the Roles of Gut Microbiota.

Evid Based Complement Alternat Med 2019 17;2019:8496817. Epub 2019 Dec 17.

Department of Pharmacy, Beijing Hospital, National Center of Gerontology, Assessment of Clinical Drugs Risk and Individual Application Key Laboratory, Beijing 100730, China.

Niuhuang Jiedu tablet (NJT), a realgar (AsS) containing Traditional Chinese Medicine (TCM), is a well-known formula. The safety of NJT is of growing concern since arsenic (As) is considered as one of the most toxic elements. NJT was demonstrated to be safer than realgar by our previous experiments and some other studies. The toxicity of realgar has been shown to be related to the amount of soluble or bioaccessible arsenic. In this study, the influences of the other TCMs in NJT on the bioaccessibility of arsenic from realgar, and the roles of gut microbiota during this process were investigated . Results showed that Dahuang (), Huangqin (), Jiegeng (), and Gancao () could significantly reduce the bioaccessibility of arsenic from realgar in artificial gastrointestinal fluids. Gut microbiota played an important role in decreasing the bioaccessibility of realgar because it was demonstrated to be able to absorb the soluble arsenic from realgar in the incubation medium. Dahuang, Huangqin, and Jiegeng could modulate the gut microbiota to enhance its arsenic absorption activity.
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http://dx.doi.org/10.1155/2019/8496817DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6942848PMC
December 2019

Screening and quantification of fourteen synthetic antidiabetic adulterants in herbal pharmaceuticals and health foods by HPLC and confirmation by LC-Q-TOF-MS/MS.

Food Addit Contam Part A Chem Anal Control Expo Risk Assess 2020 Jan 15;37(1):11-18. Epub 2019 Oct 15.

Department of Pharmaceutical Science, Beijing Hospital, National Center of Gerontology, Beijing, China.

A procedure was established and fully validated for the screening and quantification of fourteen synthetic antidiabetic adulterants in herbal pharmaceuticals and health foods, including metformin (MF), buformin (BF), phenformin (PHF), rosiglitazone (RGZ), pioglitazone (PGZ), chlorpropamide (CPM), glipizide (GPZ), tolbutamide (TBM), gliclazide (GCZ), glibenclamide (GBM), glimepiride (GMR), repaglinide (RGN), gliquidone (GQD) and nateglinide (NGN). The samples were extracted by methanol and separated by HPLC. Retention times and ultraviolet spectra were used for the preliminary screening, and the suspected adulterants were then confirmed by liquid chromatography-quadrupole-time of flight mass spectrometry (LC-Q-TOF-MS/MS) and quantified by HPLC. The developed procedure was successfully applied to assess twenty-four herbal samples, and PHF, GCZ, GBM, MF, GPZ and BF were found in many. To the best of our knowledge, this is the first report of simultaneous screening and quantification of these fourteen synthetic antidiabetic adulterants from any matrix.
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http://dx.doi.org/10.1080/19440049.2019.1675910DOI Listing
January 2020

MiRNA-217 accelerates the proliferation and migration of bladder cancer via inhibiting KMT2D.

Biochem Biophys Res Commun 2019 11 20;519(4):747-753. Epub 2019 Sep 20.

Department of Urology, Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangzhou, 510060, Guangdong, China. Electronic address:

To uncover the biological function of miRNA-217 in the progression of bladder cancer and the underlying mechanism. Potential miRNAs binding KMT2D were predicted through online bioinformatics. Their expression levels in bladder cancer tissues and adjacent ones were determined. Through Pearson correlation analysis and survival analysis, the most potential miRNA candidate (miRNA-217) that targets and regulates KMT2D in bladder cancer was selected. Subsequently, expression levels of miRNA-217 and KMT2D in non-muscle invasive bladder cancer (NMIBC) and muscle invasive bladder cancer (MIBC) were detected. MiRNA-217 level in bladder cancer cell lines was determined as well. The interaction between KMT2D and miRNA-217 was verified by dual-luciferase reporter gene assay. Finally, regulatory effect of miRNA-217 on viability and migration in T24 and UMUC-3 cells were investigated. Five potential candidates that were upstream genes binding KMT2D were searched by bioinformatics. Among them, miRNA-217 was remarkably upregulated in bladder cancer tissues and closely linked to poor prognosis of affected patients. Moreover, dual-luciferase reporter gene assay verified the interaction between miRNA-217 and KMT2D. MiRNA-217 was able to downregulate mRNA and protein levels of KMT2D. Furthermore, knockdown of miRNA-217 attenuated viability and migration in bladder cancer cells. MiRNA-217 accelerates proliferative and migratory abilities in bladder cancer via inhibiting the level of tumor suppressor KMT2D, thereafter leading to the poor prognosis in bladder cancer patients.
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http://dx.doi.org/10.1016/j.bbrc.2019.09.029DOI Listing
November 2019

A Robust Tb-MOF for Ultrasensitive Detection of Trinitrophenol: Matched Channel Dimensions and Strong Host-Guest Interactions.

Inorg Chem 2019 Jun 6;58(12):8198-8207. Epub 2019 Jun 6.

Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of Ministry of Education, College of Chemistry and Materials Science , Northwest University , Xi'an 710127 , China.

Host-Guest interaction is crucial to the sensitivity of heterogeneous sensors. Here, a series of isomorphic three-dimensional lanthanide metal-organic frameworks (Ln-MOFs), [Ln(TCBA)(HO)]·DMF [HTCBA = tris(3'-carboxybiphenyl)amine; Ln = Tb (1), Eu (2), and Gd (3); DMF = dimethylformamide] was synthesized and characterized, in which the propeller-like TCBA ligands adopt special torsional link between Tb(III) ions to form one-dimensional triangular channels. Optical experiments show that 1 exhibits bright green luminescence with an overall quantum yield of 26%, a D lifetime of 478 μs, and can act as an excellent heterogeneous fluorescent sensor to detect 2,4,6-trinitrophenol (TNP) explosive with an extremely low detection limit of 1.64 ppb. Because the confined channels within 1 exhibit matched dimensions toward TNP and feature multiple guest-response sites including rich π-conjugated groups, electron-donating N centers, and open metal nodes, strong host-guest interactions between 1 and TNP are captured and accurately determined by online microcalorimetry, which provides a distinctive thermodynamic perspective to understand the heterogeneous sensing behaviors. Additionally, the finely modulated heterometallic isomorphism [TbEu(TCBA)(HO)]·DMF emits bright white light when excited at 380 nm and could potentially be used as single-phase white light-emitting diode phosphors materials.
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http://dx.doi.org/10.1021/acs.inorgchem.9b01008DOI Listing
June 2019

Amperometric hydrogen peroxide sensor using a glassy carbon electrode modified with a nanocomposite prepared from ferumoxytol and reduced graphene oxide decorated with platinum nanoparticles.

Mikrochim Acta 2019 05 29;186(6):386. Epub 2019 May 29.

Chongqing Key Laboratory of Nano/Micro Composite Materials and Devices, Chongqing University of Science and Technology, No. 12 East road, University town, Chongqing, 401331, People's Republic of China.

A high-performance electrochemical HO sensor was prepared by constructing multiple interfaces using platinum nanoparticles (Pt NPs), ferumoxytol (Fer) and reduced graphene oxide (rGO) on a glassy carbon electrode (GCE). The morphology of Fer/rGO and Fer/rGO-Pt was characterized by field emission scanning electron microscopy and energy-dispersive X-ray spectroscopy. Cyclic voltammetry and chronoamperometry were adopted to characterize the electrochemical properties of the sensor. Because of the synergistic catalytic effect of the compositions (rGO, Fer and Pt NPs) on the multiple interfaces, the sensor exhibits particularly high electrocatalytic activity toward the reduction of HO with a low detection limit (~0.38 μM), a linear range (0.0004-0.01, 0.0075-4.3 and 4.9-10.8 mM), and a high sensitivity (340 μA mM cm, n = 4) operated at a typical working voltage of +0.1 V (vs. Ag/AgCl). The electrode is selective and long-term stable. It was successfully applied to the determination of HO in (spiked) milk samples. Graphical abstract Schematic presentation of an electrochemical HO sensor using platinum nanoparticles (Pt NPs), ferumoxytol (Fer) and reduced graphene oxide (rGO) nanocomposites modified glassy carbon electrode (GCE). The sensor was applied to the determination of HO in (spiked) milk samples.
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http://dx.doi.org/10.1007/s00604-019-3502-xDOI Listing
May 2019

Dopamine-assisted immobilization of peptide arginine-glycine-aspartic acid to enhance the cellular performances of MC3T3-E1 cells of carbon-carbon composites.

J Biomater Appl 2019 08 2;34(2):284-296. Epub 2019 May 2.

1 Chongqing Key Laboratory of Nano/Micro Composite Material and Device, School of Metallurgy and Materials Engineering, Chongqing University of Science and Technology, Chongqing, China.

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http://dx.doi.org/10.1177/0885328219845962DOI Listing
August 2019

Comparative genomic analysis of Bacillus paralicheniformis MDJK30 with its closely related species reveals an evolutionary relationship between B. paralicheniformis and B. licheniformis.

BMC Genomics 2019 Apr 11;20(1):283. Epub 2019 Apr 11.

College of Life Sciences / National Engineering Laboratory for Efficient Utilization of Soil and Fertilizer Resources / Shandong Key Laboratory of Agricultural Microbiology, Shandong Agricultural University, Tai'an, People's Republic of China.

Background: Members of the genus Bacillus are important plant growth-promoting rhizobacteria that serve as biocontrol agents. Bacillus paralicheniformis MDJK30 is a PGPR isolated from the peony rhizosphere and can suppress plant-pathogenic bacteria and fungi. To further uncover the genetic mechanism of the plant growth-promoting traits of MDJK30 and its closely related strains, we used comparative genomics to provide insights into the genetic diversity and evolutionary relationship between B. paralicheniformis and B. licheniformis.

Results: A comparative genomics analysis based on B. paralicheniformis MDJK30 and 55 other previously reported Bacillus strains was performed. The evolutionary position of MDJK30 and the evolutionary relationship between B. paralicheniformis and B. licheniformis were evaluated by studying the phylogeny of the core genomes, a population structure analysis and ANI results. Comparative genomic analysis revealed various features of B. paralicheniformis that contribute to its commensal lifestyle in the rhizosphere, including an opening pan genome, a diversity of transport and the metabolism of the carbohydrates and amino acids. There are notable differences in the numbers and locations of the insertion sequences, prophages, genomic islands and secondary metabolic synthase operons between B. paralicheniformis and B. licheniformis. In particular, we found most gene clusters of Fengycin, Bacitracin and Lantipeptide were only present in B. paralicheniformis and were obtained by horizontal gene transfer (HGT), and these clusters may be used as genetic markers for distinguishing B. paralicheniformis and B. licheniformis.

Conclusions: This study reveals that MDJK30 and the other strains of lineage paralicheniformis present plant growth-promoting traits at the genetic level and can be developed and commercially formulated in agriculture as PGPR. Core genome phylogenies and population structure analysis has proven to be a powerful tool for differentiating B. paralicheniformis and B. licheniformis. Comparative genomic analyses illustrate the genetic differences between the paralicheniformis-licheniformis group with respect to rhizosphere adaptation.
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http://dx.doi.org/10.1186/s12864-019-5646-9DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6458615PMC
April 2019

[PD-1 overexpression in HEK293T cells transfected with pMH3-PD1].

Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi 2018 Sep;34(9):800-805

The School of Basic Medical Science, Southwest Medical University, Luzhou 646000, China. *Corresponding author, E-mail:

Objective To optimize the transfection conditions of HEK293T cells and compare the expression levels of human programmed death 1 (hPD-1) in different eukaryotic vectors to obtain the target protein efficiently. Methods L9(33) orthogonal test was designed to optimize the conditions of cell transfection.The DNA sequence of hPD-1 extracellular domain gene was amplified by PCR and then cloned into different vectors:pcDNA3.1, pCMV3 and pMH3, PD-1 recombinant protein was expressed in HEK293T cells transiently and the expression levels was evaluated by ELISA and Western blot analysis. Results The gene of hPD-1 extracellular domain was successfully cloned into pcDNA3.1 and pMH3 eukaryotic expression vectors, and the target protein was successfully expressed. Under the optimal transfection conditions, the expression level of hPD-1 recombinant protein in pMH3 vector was the highest, followed by that of pCMV3 and pcDNA3.1 vectors. Conclusion The extracellular domain of hPD-1 is successfully expressed and the expression level of pMH3-PD1 was the highest among the three vectors tested.
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September 2018

New insights into oxidative stress and inflammation during diabetes mellitus-accelerated atherosclerosis.

Redox Biol 2019 01 19;20:247-260. Epub 2018 Oct 19.

The School of Basic Medical Sciences, Southwest Medical University, Luzhou, Sichuan Province 646000, China. Electronic address:

Oxidative stress and inflammation interact in the development of diabetic atherosclerosis. Intracellular hyperglycemia promotes production of mitochondrial reactive oxygen species (ROS), increased formation of intracellular advanced glycation end-products, activation of protein kinase C, and increased polyol pathway flux. ROS directly increase the expression of inflammatory and adhesion factors, formation of oxidized-low density lipoprotein, and insulin resistance. They activate the ubiquitin pathway, inhibit the activation of AMP-protein kinase and adiponectin, decrease endothelial nitric oxide synthase activity, all of which accelerate atherosclerosis. Changes in the composition of the gut microbiota and changes in microRNA expression that influence the regulation of target genes that occur in diabetes interact with increased ROS and inflammation to promote atherosclerosis. This review highlights the consequences of the sustained increase of ROS production and inflammation that influence the acceleration of atherosclerosis by diabetes. The potential contributions of changes in the gut microbiota and microRNA expression are discussed.
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http://dx.doi.org/10.1016/j.redox.2018.09.025DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6205410PMC
January 2019

Optimization and qualification of the single molecule array digital immunoassay for IL-12p70 in plasma of cancer patients.

Bioanalysis 2018 Sep 5;10(17):1413-1425. Epub 2018 Sep 5.

Bioanalytical Sciences, Genentech Inc, 660 E. Grand Avenue, South South San Francisco, CA 94080, USA.

Aim: Cytokine/chemokine levels can reflect the pharmacodynamics of checkpoint inhibitors. The single molecule array (Simoa) HD-1 is a sensitive next-generation immunoassay platform for quantification of low abundance proteins, with potential for cancer immunotherapy mechanism of action studies.

Results: The Simoa IL-12p70 reagents, standard curve and test conditions were optimized for improved precision and linearity of dilution in plasma of cancer patients. The assay achieved a lower limit of quantification of 0.08 pg/ml, with 27/29 samples recording above lower limit of quantification, precision ≤20% CV and accuracy within 80-120%.

Conclusion: Simoa enabled quantification of IL-12p70 at sub-pg/ml levels in cancer patients and was superior to Simple Plex™ and Aushon in overall performance. This study qualifies the user-modified IL-12p70 immunoassay to measure pharmacodynamic changes in plasma during cancer immunotherapy.
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http://dx.doi.org/10.4155/bio-2018-0083DOI Listing
September 2018

Metabolic Profiling Analysis of the Alleviation Effect of the Fractions of Niuhuang Jiedu Tablet on Induced Toxicity in Rats.

Evid Based Complement Alternat Med 2018 23;2018:2154603. Epub 2018 Jan 23.

Department of Pharmacy, National Center of Gerontology, Beijing Hospital, Beijing 100730, China.

Niuhuang Jiedu Tablet (NJT) is a classical formula in treating acute tonsillitis, pharyngitis, and so on. In the formula, significant level of as a potentially toxic element is contained. Our previous experiments revealed that it was less toxic for combined in NJT. However, the active fraction of this prescription with toxicity alleviation effect on was still obscure. NJT was divided into five different polar fractions (NJT-PET, NJT-25, NJT-50, NJT-75, and NJT-95), and we explored the toxicity alleviation effect on . Based on H NMR spectra of urine and serum from rats, PCA and PLS-DA were performed to identify different metabolic profiles. Liver and kidney histopathology examinations and serum clinical chemistry analysis were also performed. With pattern recognition analysis of metabolites in urine and serum, Realgar group showed a clear separation from control group, while the metabolic profiles of NJT-PET, NJT-25, NJT-50, and NJT-95 groups were similar to Realgar group, and the metabolic profiles of NJT and NJT-75 groups were very close to control group. Statistics results were confirmed by the histopathological examination and biochemical assay. The present work indicated that 75% EtOH fraction of NJT was the most valid fraction with the toxicity alleviation effect on .
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http://dx.doi.org/10.1155/2018/2154603DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5828372PMC
January 2018

HIF1α deletion facilitates adipose stem cells to repair renal fibrosis in diabetic mice.

In Vitro Cell Dev Biol Anim 2018 Apr 6;54(4):272-286. Epub 2018 Mar 6.

Department of Pathology, Medical school, Hunan University of Chinese Medicine, No.300, Xueshi Road, Hanpu kejiao Park, Yuelu District, Changsha, Hunan Province, 410208, China.

Adipose stem cell (ASC) transplantation is a promising therapeutic strategy for diabetic renal fibrosis. Hypoxia-inducible factor 1α (HIF1α) is a negative regulatory factor of mitochondrial function. In the current study, we aimed to explore if HIF1α deletion protects against hyperglycemia-induced ASC damage and enhances the therapeutic efficiency of ASCs in diabetic renal fibrosis. Our data indicated that HIF1α was upregulated in ASCs in response to high glucose stimulation. Higher HIF1α expression was associated with ASC apoptosis and proliferation arrest. Loss of HIF1α activated mitophagy protecting ASCs against high glucose-induced apoptosis via preserving mitochondrial function. Transplanting HIF1α-deleted ASCs in db/db mice improved the abnormalities in glucose metabolic parameters, including the levels of glucose, insulin, C-peptide, HbA1c, and inflammatory markers. In addition, the engraftment of HIF1α-modified ASCs also reversed renal function, decreased renal hypertrophy, and ameliorated renal histological changes in db/db mice. Functional studies confirmed that HIF1α-modified ASCs reduced renal fibrosis. Collectively, our results demonstrate that ASCs may be a promising therapeutic treatment for ameliorating diabetes and the development of renal fibrosis and that the loss of HIF1α in ASCs may further increase the efficiency of stem cell-based therapy. These findings provide a new understanding about the protective effects of HIF1α silencing on ASCs and offer a new strategy for promoting the therapeutic efficacy of ASCs in diabetic renal fibrosis.
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http://dx.doi.org/10.1007/s11626-018-0231-0DOI Listing
April 2018

Complete Genome Sequence of GQJK49, a Plant Growth-Promoting Rhizobacterium with Antifungal Activity.

Genome Announc 2017 Aug 31;5(35). Epub 2017 Aug 31.

College of Life Sciences/Shandong Key Laboratory of Agricultural Microbiology/National Engineering Laboratory for Efficient Utilization of Soil and Fertilizer Resources, Shandong Agricultural University, Tai'an, China

GQJK49 is a plant growth-promoting rhizobacterium with antifungal activity, which was isolated from L. rhizosphere. Here, we report the complete genome sequence of GQJK49. Twelve gene clusters related to its biosynthesis of secondary metabolites, including antifungal and antibacterial antibiotics, were predicted.
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http://dx.doi.org/10.1128/genomeA.00922-17DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5578859PMC
August 2017

Complete Genome Sequence of MDJK30, a Plant Growth-Promoting Rhizobacterium with Antifungal Activity.

Genome Announc 2017 Jun 22;5(25). Epub 2017 Jun 22.

College of Life Sciences/Shandong Key Laboratory of Agricultural Microbiology/National Engineering Laboratory for Efficient Utilization of Soil and Fertilizer Resources, Shandong Agricultural University, Tai'an, China

MDJK30 was isolated from the rhizosphere of a peony. It could control the pathogen of peony root rot. Here, we report the complete genome sequence of MDJK30. Eleven secondary metabolism gene clusters were predicted.
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http://dx.doi.org/10.1128/genomeA.00577-17DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5481586PMC
June 2017

Complete Genome Sequence of Biocontroller Strain JTYP2, Isolated from Leaves of .

Genome Announc 2017 Jun 15;5(24). Epub 2017 Jun 15.

College of Life Sciences, Shandong Key Laboratory of Agricultural Microbiology, National Engineering Laboratory for Efficient Utilization of Soil and Fertilizer Resources, Shandong Agricultural University, Tai'an, China

JTYP2 was isolated from the leaves of in Qingzhou, China, and may control some of the fungal pathogens of the plant. Here, we present the complete genome sequence of JTYP2. Several gene clusters related to its biosynthesis of antimicrobial compounds were predicted.
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http://dx.doi.org/10.1128/genomeA.00505-17DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5473263PMC
June 2017

Complete Genome Sequence of YC0573, a Plant Growth-Promoting Rhizobacterium with Antimicrobial Activity.

Genome Announc 2017 Feb 9;5(6). Epub 2017 Feb 9.

College of Life Sciences, Shandong Key Laboratory of Agricultural Microbiology, National Engineering Laboratory for Efficient Utilization of Soil and Fertilizer Resources, Shandong Agricultural University, Taian, China

strain YC0573 is a plant growth-promoting rhizobacterium with antimicrobial activity, which was isolated from tobacco rhizosphere. Here, we report the complete genome sequence of YC0573. Antifungal and antibacterial genes were discovered.
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http://dx.doi.org/10.1128/genomeA.01636-16DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5331515PMC
February 2017

Complete Genome Sequence of YC0136, a Plant Growth-Promoting Rhizobacterium Isolated from Tobacco Rhizosphere.

Genome Announc 2017 Feb 9;5(6). Epub 2017 Feb 9.

College of Life Sciences/Shandong Key Laboratory of Agricultural Microbiology/ National Engineering Laboratory for Efficient Utilization of Soil and Fertilizer Resources, Shandong Agricultural University, Taian, China

strain YC0136 is a plant growth-promoting rhizobacterium with antimicrobial activity, which was isolated from tobacco rhizosphere. Here, we report the complete genome sequence of YC0136. Several genes with antifungal and antibacterial activity were discovered.
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http://dx.doi.org/10.1128/genomeA.01635-16DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5331514PMC
February 2017

Bioanalytical qualification of clinical biomarker assays in plasma using a novel multi-analyte Simple Plex platform.

Bioanalysis 2016 Dec;8(23):2415-2428

BioAnalytical Sciences, Genentech Inc, South San Francisco, CA 94080, USA.

Aim: Immune-checkpoint inhibitors are presumed to break down the tolerogenic state of immune cells by activating T-lymphocytes that release cytokines and enhance effector cell function for elimination of tumors. Measurement of cytokines is being pursued for better understanding of the mechanism of action of immune-checkpoint inhibitors, as well as to identify potential predictive biomarkers.

Results: In this study, we show bioanalytical qualification of cytokine assays in plasma on a novel multi-analyte immunoassay platform, Simple Plex. The qualified assays exhibited excellent sensitivity as evidenced by measurement of all samples within the quantifiable range. The accuracy and precision were 80-120% and 10%, respectively.

Conclusion: The qualified assays will be useful in assessing mechanism of action cancer immunotherapies.
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http://dx.doi.org/10.4155/bio-2016-0196DOI Listing
December 2016

Comparative Genomic Analysis of MTQ3 and the Identification of Functional NRPS Genes for Siderophore Production.

Biomed Res Int 2016 25;2016:3687619. Epub 2016 Oct 25.

College of Life Sciences/Shandong Key Laboratory of Agricultural Microbiology, Shandong Agricultural University, Tai'an, China.

Plant growth-promoting rhizobacteria (PGPR) are a group of rhizosphere bacteria that promote plant growth. MTQ3 is a member of PGPR that produces siderophores. The draft genome sequence of MTQ3 has been reported. Here, we analyzed the genome sequence of MTQ3 and performed a comparative genome analysis of four sequenced strains, revealing genetic relationships among these strains. In addition, genes responsible for bacteriocin and nonribosomal peptide synthesis were detected in the genomes of each strain. To reveal the functions of NRPS genes in siderophore production in MTQ3, three NRPS genes were knocked out to obtain the three mutants MTQ3-Δ1941, MTQ3-Δ1945, and MTQ3-Δ1946, which were compared with the wild-type strain. In qualitative and quantitative analyses using CAS assay, the mutants failed to produce siderophores. Accordingly, the NRPS genes in MTQ3 were functionally related to siderophore production. These results clarify one mechanism by which plant growth is promoted in MTQ3 and have important applications in agricultural production.
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http://dx.doi.org/10.1155/2016/3687619DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5099486PMC
March 2017

Preparation of bioactive β-tricalcium phosphate microspheres as bone graft substitute materials.

Mater Sci Eng C Mater Biol Appl 2017 Jan 23;70(Pt 2):1200-1205. Epub 2016 Mar 23.

Institute of Biomaterials and Living Cell Imaging Technology, Chongqing Key Laboratory of Nano/Micro Composite Materials and Devices, Chongqing University of Science and Technology, Chongqing 401331, China. Electronic address:

In this study, β-tricalcium phosphate (CaPO, β-TCP) microspheres with different diameters were fabricated via a solid-in-oil-in-water (S/O/W) emulsion method. After soaking in simulated body fluid (SBF), the fabricated β-TCP microspheres were fully covered with a new bone-like apatite layer; subsequent analysis suggested that the microspheres have excellent bioactivity properties, specifically in inducing apatite deposition. The calcium release profiles of the microspheres were tested in pH7.4 Tris-HCl buffer, and results demonstrated that the Ca continually released from microspheres during the two-week test period. We then co-cultured bone marrow stem cells (BMSCs) in vitro with β-TCP microspheres, and performed SEM and confocal microscope analyses to find that β-TCP microspheres efficiently promoted BMSC attachment and bone-related gene expression. The co-cultured BMSCs and microspheres were successfully implanted subcutaneously into nude mice for 8weeks. The H&E neo-tissue staining results showed that abundant new bone-like structures had formed between the β-TCP microspheres, implying that β-TCP microspheres used as a cell carrier and bone graft substitute material show highly promising potential application for irregular-shaped bone defect regeneration.
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http://dx.doi.org/10.1016/j.msec.2016.03.040DOI Listing
January 2017

Development and identification of fully human scFv-Fcs against Staphylococcus aureus.

BMC Immunol 2016 04 29;17(1). Epub 2016 Apr 29.

The School of Basic Medical Sciences, Sichuan medical university, Room 218, Hanguang building, No 319, Zhongshan road, Luzhou, Sichuan, 646000, China.

Background: Staphylococcus aureus, a gram-positive pathogen, causes many human infections. Methicillin-resistant S. aureus (MRSA) is the most common drug-resistance bacteria. Nearly all MRSA bacteria are resistant to several drugs. Specific antibodies are the main components of the host's humoral immunity, and play a significant role in the process of the host's resistance to bacterial infection.

Results: A single-chain variable fragment (scFv) library was constructed using mRNA from the peripheral blood mononuclear cells of S. aureus infected volunteers. After the scFv library DNA was transformed into Escherichia coli TG1, ~1.7 × 10(7) independent clones with full-length scFv inserts. The scFv library was screened by phage display for three rounds using S. aureus as an antigen. The single clones were chosen at random and the scFvs were expressed for enzyme-linked immunosorbent assay (ELISA) assessment. Approximately 50 % of the clones were positive with good binding activity to S. aureus. To improve the stability of scFvs, scFv-fragment crystallizable regions (-Fcs) were constructed and expressed in E. coli DH5α. The expressed scFv-Fcs were purified and identified by western blot. These antibodies were further characterized and analyzed for bioactivity. The results showed that the expression level and folding of scFv-Fcs induced at 25 °C without isopropyl β-D-1-thiogalactopyranoside (IPTG) were higher than that induced at 32 °C with 1.0 mmol/L IPTG. scFv-Fcs had good bioactivity and could specifically bind with S. aureus.

Conclusion: scFv-Fcs against S. aureus were successfully constructed and are good candidates for the development of future adjunctive therapy for severe S. aureus infections.
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http://dx.doi.org/10.1186/s12865-016-0146-zDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4850644PMC
April 2016

[Stable expression of human anti-IL-33 scFv-IgG1Fc fusion protein in CHO k1 cells].

Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi 2016 May;32(5):600-3, 608

School of Basic Medic Science, Sichuan Medical University, Luzhou 646000, China. *Corresponding author, E-mail:

Objective: To construct two different eukaryotic expression vectors of human anti-interleukin 33 (IL-33) single-chain antibody fragment (scFv-Fc) to transfect Chinese hamster ovary (CHO) k1 cells and select the stably and high-level expressed cell lines to improve the expression level of the fusion protein.

Methods: The previously constructed recombinant plasmid pcDNA3.1/SP-scFv-Fc was digested to obtain SP-scFv-Fc fragments, and the fragments were inserted into the plasmid PMH3(EN) to construct recombinant plasmid PMH3(EN)/SP-scFv-Fc. The plasmids PMH3(EN)/SP-scFv-Fc and pcDNA3.1/SP-scFv-Fc were separately transfected into CHO k1 cells. The transcription and translation level of the SP-scFv-Fc were detected by reverse transcription PCR (RT-PCR) and Western blotting, respectively. The stably and high-level expressed cell lines were screened by Dot blotting. The expression level and binding activity of the expressed scFv-Fc were measured by ELISA.

Results: The recombinant plasmid PMH3(EN)/SP-scFv-Fc was successfully constructed and the size of the inserted SP-scFv-Fc was about 1560 bp. The RT-PCR results showed that the SP-scFv-Fc was successfully transfected into CHO k1 cells. The scFv-Fc proteins could be secreted into the cultural supernatant and specifically bind to human IL-33 and anti human IgG1 Fc antibody. The expression level of scFv-Fc in plasmid PMH3(EN) was higher than that in plasmid pcDNA3.1. After four rounds of screening, the stably and high-level expressed cell strains were obtained. The expression level of the scFv-Fc was about 10 mg/L. The competitive ELISA results showed that the expressed scFv-Fc fusion proteins could inhibit the binding of IL-33 to ST2.

Conclusion: The anti-IL-33 scFv-Fc proteins were highly expressed in CHO k1 cells.
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May 2016