1.Effect of cell culture conditions on antibody heterogeneity.
Xujie DUAN ; Rui LIU ; Weitao XU ; Tong REN ; Houyong LUO
Chinese Journal of Biotechnology 2013;29(12):1880-1886
With the advantage of clear target and little side effect, antibody drug has attracted widely attention of worldwide pharmaceutical companies. However, large scale mammalian cell culture and antibody quality analysis are the bottlenecks of antibody drug industrialization in China. Especially due to the significant effect of cell culture conditions on antibody heterogeneity. Therefore, it is extremely urgent to optimize cell culture conditions to favor the demands of antibody drug development. This review summarized the most recent advances in the effect of cell culture conditions on antibody quality, followed by addressing the key issues that might be strategically important for domestic antibody drug development.
Animals
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Antibodies, Monoclonal
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biosynthesis
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isolation & purification
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Antibody Formation
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Cell Culture Techniques
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methods
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trends
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Genetic Heterogeneity
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Protein Stability
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Quality Control
2.The Interaction Between the Symbiotic Genes pJB5JI of Rhizobium Leguminosarum bv. Viciae and the Symbiotic Plasmid of Mesorhizobium huakuii 7653R
Chengyun YANG ; Junchu ZHOU ; Guangcai DUAN ; Weitao ZHANG
Microbiology 2008;0(11):-
Mesorhizobium huakuii strain 7653R,isolated from nodules of A.sinicus L,contains two indige-nous plasmids,p7653Ra and p7653Rb,the latter being the symbiotic plasmid.We eliminated the plasmids via Tn5-sacB insertion and obtained its symbiotic plasmid-cured derivative 7653RD.Then,we transferred the symbiotic plasmid pJB5JI of Rhizobium leguminosarum bv.Viciae T83K3 into 7653R and 7653RD.The pot plant test showed an increase in competitive ability and symbiotic nitrogen fixation of transconjugant 7653R-197(pJB5JI) compared to 7653R.pJB5JI could not restore the ability of 7653RD to nodulate Astra-galus sinicus.7653RD(pJB5JI) could form ineffective nodules on peas,implying that the symbiotic plasmid pJB5JI could express its function at the chromosomal background of Mesorhizobium huakuii 7653R.We checked the stability of plasmid in transconjugants under free-living and during symbiosis.The results indi-cated pJB5JI could not be detected in some nodule isolates.We amplified kan resistance gene from all transconjugants and nodule isolates which suggested that pJB5JI might fully or partially integrated into the chromosome of recipients.
4.Study of left ventricular myocardial mechanics in patients with different risk stratifications of hypertrophic cardiomyopathy by four-dimensional automatic left ventricular quantitation technology
Silu DAI ; Lina WU ; Weitao GUO ; Honghu WANG ; Wenqiang SHI ; Huican DUAN ; Lingyun WANG ; Xi ZHAO ; Ruifang ZHANG
Chinese Journal of Ultrasonography 2023;32(4):295-302
Objective:To explore the application value of four-dimensional automatic left ventricular quantitation(4D Auto LVQ) technology, in evaluating the myocardial mechanics in patients with different risk stratifications of hypertrophic cardiomyopathy(HCM).Methods:A total of 88 HCM patients and 20 healthy volunteers were selected from February 2020 to February 2022 in the First Affiliated Hospital of Zhengzhou University. According to the HCM Risk-SCD score, HCM patients were divided into 3 groups: low-risk group( n=49), intermediate-risk group( n=21), and high-risk group( n=18). Conventional ultrasound parameters were collected, and 4D Auto LVQ technology was used to obtain the mechanical parameters of left ventricular myocardium, including global longitudinal strain(GLS) , global circumferential strain(GCS), global area strain(GAS), global radial strain(GRS), twist and torsion. The differences in these parameters among the four groups were compared. The predictive values of conventional ultrasound parameters and myocardial mechanical parameters in patients with intermediate- and high-risk HCM patients were analyzed by ROC curve. Results:①Left ventricular end-diastolic diameter, left ventricular end-diastolic volume, left ventricular end-systolic volume, and peak systolic velocity of mitral annulus in the low-, intermediate-, and high-risk groups were lower than those in the control group while left ventricular maximal wall thickness(LVMWT) and early diastolic peak velocity of mitral value orifice/early diastolic peak velocity of mitral annulus(E/e′) were higher, left atrial diameter(LAD) and left ventricular outflow tract gradients(LVOTG) in the intermediate- and high-risk groups were higher than the low-risk group(all P<0.05). ②Compared with the control group, the GLS of HCM patients was lower, and the GLS of the intermediate- and high-risk groups was lower than the low-risk group. GCS and GRS in the intermediate- and high-risk groups were lower than those in the low-risk group. GAS in the high-risk group was lower than the low-risk and the control group, but higher than the intermediate-risk group(all P<0.05). Compared with the control group, the twist and torsion in the intermediate- and high-risk groups were higher, but lower than the low-risk group, and the differences were statistically significant(all P<0.05). ③The ROC results showed that the area under the curve(AUC) of the model containing conventional ultrasound parameters(LVWMT, LAD, and LVOTG) for predicting intermediate- and high-risk HCM patients was 0.811, with a sensitivity of 0.769 and a specificity of 0.755. The AUC of the conventional ultrasound parameters combined with myocardial mechanical parameters was 0.904, as the sensitivity was 0.667 and the specificity was 0.980. Conclusions:4D Auto LVQ can evaluate the mechanical characteristics of LV myocardium in HCM patients with different risk stratifications. Myocardial mechanical parameters combined with conventional ultrasound parameters can improve the diagnostic performance of patients with intermediate- and high-risk HCM.
5.Discovery of Novel Androgen Receptor Ligands by Structure-based Virtual Screening and Bioassays.
Wenfang ZHOU ; Mojie DUAN ; Weitao FU ; Jinping PANG ; Qin TANG ; Huiyong SUN ; Lei XU ; Shan CHANG ; Dan LI ; Tingjun HOU
Genomics, Proteomics & Bioinformatics 2018;16(6):416-427
Androgen receptor (AR) is a ligand-activated transcription factor that plays a pivotal role in the development and progression of many severe diseases such as prostate cancer, muscle atrophy, and osteoporosis. Binding of ligands to AR triggers the conformational changes in AR that may affect the recruitment of coactivators and downstream response of AR signaling pathway. Therefore, AR ligands have great potential to treat these diseases. In this study, we searched for novel AR ligands by performing a docking-based virtual screening (VS) on the basis of the crystal structure of the AR ligand binding domain (LBD) in complex with its agonist. A total of 58 structurally diverse compounds were selected and subjected to LBD affinity assay, with five of them (HBP1-3, HBP1-17, HBP1-38, HBP1-51, and HBP1-58) exhibiting strong binding to AR-LBD. The IC values of HBP1-51 and HBP1-58 are 3.96 µM and 4.92 µM, respectively, which are even lower than that of enzalutamide (Enz, IC = 13.87 µM), a marketed second-generation AR antagonist. Further bioactivity assays suggest that HBP1-51 is an AR agonist, whereas HBP1-58 is an AR antagonist. In addition, molecular dynamics (MD) simulations and principal components analysis (PCA) were carried out to reveal the binding principle of the newly-identified AR ligands toward AR. Our modeling results indicate that the conformational changes of helix 12 induced by the bindings of antagonist and agonist are visibly different. In summary, the current study provides a highly efficient way to discover novel AR ligands, which could serve as the starting point for development of new therapeutics for AR-related diseases.
Androgen Receptor Antagonists
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pharmacology
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Androgens
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metabolism
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pharmacology
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Biological Assay
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Cell Line, Tumor
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Drug Discovery
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methods
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Humans
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Ligands
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Male
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Molecular Docking Simulation
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Molecular Dynamics Simulation
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Phenylthiohydantoin
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analogs & derivatives
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pharmacology
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Principal Component Analysis
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Prostatic Neoplasms
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drug therapy
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Protein Binding
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physiology
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Protein Conformation
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drug effects
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Receptors, Androgen
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metabolism